From 4bb9998d388b48dc0a4128bd1f4d85f09ec3b705 Mon Sep 17 00:00:00 2001 From: Masanari Iida Date: Mon, 16 Nov 2015 20:46:28 +0900 Subject: Doc: f2fs: Fix typos in Documentation/filesystems/f2fs.txt This patch fix some typos in Documentation/filesystems/f2fs.txt Signed-off-by: Masanari Iida Acked-by: Randy Dunlap Signed-off-by: Jaegeuk Kim --- Documentation/filesystems/f2fs.txt | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'Documentation/filesystems') diff --git a/Documentation/filesystems/f2fs.txt b/Documentation/filesystems/f2fs.txt index b102b436563e..ad10494aa224 100644 --- a/Documentation/filesystems/f2fs.txt +++ b/Documentation/filesystems/f2fs.txt @@ -102,7 +102,7 @@ background_gc=%s Turn on/off cleaning operations, namely garbage collection, triggered in background when I/O subsystem is idle. If background_gc=on, it will turn on the garbage collection and if background_gc=off, garbage collection - will be truned off. If background_gc=sync, it will turn + will be turned off. If background_gc=sync, it will turn on synchronous garbage collection running in background. Default value for this option is on. So garbage collection is on by default. @@ -145,7 +145,7 @@ extent_cache Enable an extent cache based on rb-tree, it can cache as many as extent which map between contiguous logical address and physical address per inode, resulting in increasing the cache hit ratio. Set by default. -noextent_cache Diable an extent cache based on rb-tree explicitly, see +noextent_cache Disable an extent cache based on rb-tree explicitly, see the above extent_cache mount option. noinline_data Disable the inline data feature, inline data feature is enabled by default. @@ -192,7 +192,7 @@ Files in /sys/fs/f2fs/ policy for garbage collection. Setting gc_idle = 0 (default) will disable this option. Setting gc_idle = 1 will select the Cost Benefit approach - & setting gc_idle = 2 will select the greedy aproach. + & setting gc_idle = 2 will select the greedy approach. reclaim_segments This parameter controls the number of prefree segments to be reclaimed. If the number of prefree @@ -298,7 +298,7 @@ The dump.f2fs shows the information of specific inode and dumps SSA and SIT to file. Each file is dump_ssa and dump_sit. The dump.f2fs is used to debug on-disk data structures of the f2fs filesystem. -It shows on-disk inode information reconized by a given inode number, and is +It shows on-disk inode information recognized by a given inode number, and is able to dump all the SSA and SIT entries into predefined files, ./dump_ssa and ./dump_sit respectively. -- cgit v1.2.3 From 21fc61c73c3903c4c312d0802da01ec2b323d174 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Tue, 17 Nov 2015 01:07:57 -0500 Subject: don't put symlink bodies in pagecache into highmem kmap() in page_follow_link_light() needed to go - allowing to hold an arbitrary number of kmaps for long is a great way to deadlocking the system. new helper (inode_nohighmem(inode)) needs to be used for pagecache symlinks inodes; done for all in-tree cases. page_follow_link_light() instrumented to yell about anything missed. Signed-off-by: Al Viro --- Documentation/filesystems/porting | 5 +++++ fs/affs/inode.c | 1 + fs/affs/namei.c | 1 + fs/affs/symlink.c | 4 +--- fs/afs/inode.c | 1 + fs/befs/linuxvfs.c | 5 ++--- fs/btrfs/inode.c | 2 ++ fs/coda/cnode.c | 2 ++ fs/coda/symlink.c | 4 +--- fs/cramfs/inode.c | 1 + fs/efs/inode.c | 1 + fs/efs/symlink.c | 4 +--- fs/exofs/inode.c | 1 + fs/exofs/namei.c | 1 + fs/ext2/inode.c | 1 + fs/ext2/namei.c | 1 + fs/ext4/inode.c | 1 + fs/ext4/namei.c | 1 + fs/ext4/symlink.c | 10 +++------- fs/f2fs/inode.c | 1 + fs/f2fs/namei.c | 5 ++--- fs/freevxfs/vxfs_inode.c | 1 + fs/hfsplus/inode.c | 2 ++ fs/hpfs/inode.c | 1 + fs/hpfs/namei.c | 5 ++--- fs/hugetlbfs/inode.c | 1 + fs/inode.c | 6 ++++++ fs/isofs/inode.c | 1 + fs/isofs/rock.c | 4 +--- fs/jfs/inode.c | 1 + fs/jfs/namei.c | 1 + fs/logfs/dir.c | 1 + fs/logfs/inode.c | 1 + fs/minix/inode.c | 1 + fs/namei.c | 9 +++------ fs/ncpfs/inode.c | 1 + fs/nfs/inode.c | 5 +++-- fs/nfs/symlink.c | 2 +- fs/nilfs2/inode.c | 1 + fs/nilfs2/namei.c | 1 + fs/ocfs2/inode.c | 1 + fs/ocfs2/namei.c | 1 + fs/qnx4/inode.c | 1 + fs/qnx6/inode.c | 1 + fs/ramfs/inode.c | 1 + fs/reiserfs/inode.c | 1 + fs/reiserfs/namei.c | 1 + fs/romfs/super.c | 1 + fs/squashfs/inode.c | 2 ++ fs/sysv/inode.c | 1 + fs/udf/inode.c | 1 + fs/udf/namei.c | 1 + fs/udf/symlink.c | 4 +--- fs/ufs/inode.c | 1 + fs/ufs/namei.c | 1 + include/linux/fs.h | 1 + mm/shmem.c | 9 +++------ 57 files changed, 81 insertions(+), 46 deletions(-) (limited to 'Documentation/filesystems') diff --git a/Documentation/filesystems/porting b/Documentation/filesystems/porting index f24d1b833957..3eb7c35c9698 100644 --- a/Documentation/filesystems/porting +++ b/Documentation/filesystems/porting @@ -504,3 +504,8 @@ in your dentry operations instead. [mandatory] __fd_install() & fd_install() can now sleep. Callers should not hold a spinlock or other resources that do not allow a schedule. +-- +[mandatory] + any symlink that might use page_follow_link_light/page_put_link() must + have inode_nohighmem(inode) called before anything might start playing with + its pagecache. diff --git a/fs/affs/inode.c b/fs/affs/inode.c index 17349500592d..0fdb0f5b2239 100644 --- a/fs/affs/inode.c +++ b/fs/affs/inode.c @@ -140,6 +140,7 @@ struct inode *affs_iget(struct super_block *sb, unsigned long ino) break; case ST_SOFTLINK: inode->i_mode |= S_IFLNK; + inode_nohighmem(inode); inode->i_op = &affs_symlink_inode_operations; inode->i_data.a_ops = &affs_symlink_aops; break; diff --git a/fs/affs/namei.c b/fs/affs/namei.c index 181e05b46e72..00d3002a6780 100644 --- a/fs/affs/namei.c +++ b/fs/affs/namei.c @@ -344,6 +344,7 @@ affs_symlink(struct inode *dir, struct dentry *dentry, const char *symname) return -ENOSPC; inode->i_op = &affs_symlink_inode_operations; + inode_nohighmem(inode); inode->i_data.a_ops = &affs_symlink_aops; inode->i_mode = S_IFLNK | 0777; mode_to_prot(inode); diff --git a/fs/affs/symlink.c b/fs/affs/symlink.c index ea5b69a18ba9..e3f9dc3ae8cc 100644 --- a/fs/affs/symlink.c +++ b/fs/affs/symlink.c @@ -14,7 +14,7 @@ static int affs_symlink_readpage(struct file *file, struct page *page) { struct buffer_head *bh; struct inode *inode = page->mapping->host; - char *link = kmap(page); + char *link = page_address(page); struct slink_front *lf; int i, j; char c; @@ -57,12 +57,10 @@ static int affs_symlink_readpage(struct file *file, struct page *page) link[i] = '\0'; affs_brelse(bh); SetPageUptodate(page); - kunmap(page); unlock_page(page); return 0; fail: SetPageError(page); - kunmap(page); unlock_page(page); return -EIO; } diff --git a/fs/afs/inode.c b/fs/afs/inode.c index e06f5a23352a..86cc7264c21c 100644 --- a/fs/afs/inode.c +++ b/fs/afs/inode.c @@ -56,6 +56,7 @@ static int afs_inode_map_status(struct afs_vnode *vnode, struct key *key) case AFS_FTYPE_SYMLINK: inode->i_mode = S_IFLNK | vnode->status.mode; inode->i_op = &page_symlink_inode_operations; + inode_nohighmem(inode); break; default: printk("kAFS: AFS vnode with undefined type\n"); diff --git a/fs/befs/linuxvfs.c b/fs/befs/linuxvfs.c index 1c8b0dca8b50..25250fa87086 100644 --- a/fs/befs/linuxvfs.c +++ b/fs/befs/linuxvfs.c @@ -397,6 +397,7 @@ static struct inode *befs_iget(struct super_block *sb, unsigned long ino) } else if (S_ISLNK(inode->i_mode)) { if (befs_ino->i_flags & BEFS_LONG_SYMLINK) { inode->i_op = &page_symlink_inode_operations; + inode_nohighmem(inode); inode->i_mapping->a_ops = &befs_symlink_aops; } else { inode->i_link = befs_ino->i_data.symlink; @@ -469,7 +470,7 @@ static int befs_symlink_readpage(struct file *unused, struct page *page) struct befs_inode_info *befs_ino = BEFS_I(inode); befs_data_stream *data = &befs_ino->i_data.ds; befs_off_t len = data->size; - char *link = kmap(page); + char *link = page_address(page); if (len == 0 || len > PAGE_SIZE) { befs_error(sb, "Long symlink with illegal length"); @@ -483,12 +484,10 @@ static int befs_symlink_readpage(struct file *unused, struct page *page) } link[len - 1] = '\0'; SetPageUptodate(page); - kunmap(page); unlock_page(page); return 0; fail: SetPageError(page); - kunmap(page); unlock_page(page); return -EIO; } diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index a70c5790f8f5..70f98bfde277 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -3774,6 +3774,7 @@ cache_acl: break; case S_IFLNK: inode->i_op = &btrfs_symlink_inode_operations; + inode_nohighmem(inode); inode->i_mapping->a_ops = &btrfs_symlink_aops; break; default: @@ -9705,6 +9706,7 @@ static int btrfs_symlink(struct inode *dir, struct dentry *dentry, btrfs_free_path(path); inode->i_op = &btrfs_symlink_inode_operations; + inode_nohighmem(inode); inode->i_mapping->a_ops = &btrfs_symlink_aops; inode_set_bytes(inode, name_len); btrfs_i_size_write(inode, name_len); diff --git a/fs/coda/cnode.c b/fs/coda/cnode.c index 7740b1c871c1..dd6a79ef4750 100644 --- a/fs/coda/cnode.c +++ b/fs/coda/cnode.c @@ -8,6 +8,7 @@ #include #include +#include #include "coda_linux.h" static inline int coda_fideq(struct CodaFid *fid1, struct CodaFid *fid2) @@ -35,6 +36,7 @@ static void coda_fill_inode(struct inode *inode, struct coda_vattr *attr) inode->i_fop = &coda_dir_operations; } else if (S_ISLNK(inode->i_mode)) { inode->i_op = &coda_symlink_inode_operations; + inode_nohighmem(inode); inode->i_data.a_ops = &coda_symlink_aops; inode->i_mapping = &inode->i_data; } else diff --git a/fs/coda/symlink.c b/fs/coda/symlink.c index ab94ef63caef..03736e20d720 100644 --- a/fs/coda/symlink.c +++ b/fs/coda/symlink.c @@ -26,7 +26,7 @@ static int coda_symlink_filler(struct file *file, struct page *page) int error; struct coda_inode_info *cii; unsigned int len = PAGE_SIZE; - char *p = kmap(page); + char *p = page_address(page); cii = ITOC(inode); @@ -34,13 +34,11 @@ static int coda_symlink_filler(struct file *file, struct page *page) if (error) goto fail; SetPageUptodate(page); - kunmap(page); unlock_page(page); return 0; fail: SetPageError(page); - kunmap(page); unlock_page(page); return error; } diff --git a/fs/cramfs/inode.c b/fs/cramfs/inode.c index 355c522f3585..b862bc219cd7 100644 --- a/fs/cramfs/inode.c +++ b/fs/cramfs/inode.c @@ -100,6 +100,7 @@ static struct inode *get_cramfs_inode(struct super_block *sb, break; case S_IFLNK: inode->i_op = &page_symlink_inode_operations; + inode_nohighmem(inode); inode->i_data.a_ops = &cramfs_aops; break; default: diff --git a/fs/efs/inode.c b/fs/efs/inode.c index 079d20306ee1..cdf0872382af 100644 --- a/fs/efs/inode.c +++ b/fs/efs/inode.c @@ -151,6 +151,7 @@ struct inode *efs_iget(struct super_block *super, unsigned long ino) break; case S_IFLNK: inode->i_op = &page_symlink_inode_operations; + inode_nohighmem(inode); inode->i_data.a_ops = &efs_symlink_aops; break; case S_IFCHR: diff --git a/fs/efs/symlink.c b/fs/efs/symlink.c index 75117d0dac2b..4870cc82deb0 100644 --- a/fs/efs/symlink.c +++ b/fs/efs/symlink.c @@ -13,7 +13,7 @@ static int efs_symlink_readpage(struct file *file, struct page *page) { - char *link = kmap(page); + char *link = page_address(page); struct buffer_head * bh; struct inode * inode = page->mapping->host; efs_block_t size = inode->i_size; @@ -39,12 +39,10 @@ static int efs_symlink_readpage(struct file *file, struct page *page) } link[size] = '\0'; SetPageUptodate(page); - kunmap(page); unlock_page(page); return 0; fail: SetPageError(page); - kunmap(page); unlock_page(page); return err; } diff --git a/fs/exofs/inode.c b/fs/exofs/inode.c index 73c64daa0f55..d8e9c18171a9 100644 --- a/fs/exofs/inode.c +++ b/fs/exofs/inode.c @@ -1227,6 +1227,7 @@ struct inode *exofs_iget(struct super_block *sb, unsigned long ino) inode->i_link = (char *)oi->i_data; } else { inode->i_op = &page_symlink_inode_operations; + inode_nohighmem(inode); inode->i_mapping->a_ops = &exofs_aops; } } else { diff --git a/fs/exofs/namei.c b/fs/exofs/namei.c index 994e078da4bb..c20d77df2679 100644 --- a/fs/exofs/namei.c +++ b/fs/exofs/namei.c @@ -111,6 +111,7 @@ static int exofs_symlink(struct inode *dir, struct dentry *dentry, if (l > sizeof(oi->i_data)) { /* slow symlink */ inode->i_op = &page_symlink_inode_operations; + inode_nohighmem(inode); inode->i_mapping->a_ops = &exofs_aops; memset(oi->i_data, 0, sizeof(oi->i_data)); diff --git a/fs/ext2/inode.c b/fs/ext2/inode.c index 0aa9bf6e6e53..338eefda70c6 100644 --- a/fs/ext2/inode.c +++ b/fs/ext2/inode.c @@ -1420,6 +1420,7 @@ struct inode *ext2_iget (struct super_block *sb, unsigned long ino) sizeof(ei->i_data) - 1); } else { inode->i_op = &ext2_symlink_inode_operations; + inode_nohighmem(inode); if (test_opt(inode->i_sb, NOBH)) inode->i_mapping->a_ops = &ext2_nobh_aops; else diff --git a/fs/ext2/namei.c b/fs/ext2/namei.c index 3267a80dbbe2..7a2be8f7f3c3 100644 --- a/fs/ext2/namei.c +++ b/fs/ext2/namei.c @@ -183,6 +183,7 @@ static int ext2_symlink (struct inode * dir, struct dentry * dentry, if (l > sizeof (EXT2_I(inode)->i_data)) { /* slow symlink */ inode->i_op = &ext2_symlink_inode_operations; + inode_nohighmem(inode); if (test_opt(inode->i_sb, NOBH)) inode->i_mapping->a_ops = &ext2_nobh_aops; else diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index ea433a7f4bca..b3bd912df6bf 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -4283,6 +4283,7 @@ struct inode *ext4_iget(struct super_block *sb, unsigned long ino) inode->i_op = &ext4_symlink_inode_operations; ext4_set_aops(inode); } + inode_nohighmem(inode); } else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode) || S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)) { inode->i_op = &ext4_special_inode_operations; diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c index a969ab39f302..f27e0c2598c5 100644 --- a/fs/ext4/namei.c +++ b/fs/ext4/namei.c @@ -3132,6 +3132,7 @@ static int ext4_symlink(struct inode *dir, if ((disk_link.len > EXT4_N_BLOCKS * 4)) { if (!encryption_required) inode->i_op = &ext4_symlink_inode_operations; + inode_nohighmem(inode); ext4_set_aops(inode); /* * We cannot call page_symlink() with transaction started diff --git a/fs/ext4/symlink.c b/fs/ext4/symlink.c index abe2401ce405..0e6dc44c5ebf 100644 --- a/fs/ext4/symlink.c +++ b/fs/ext4/symlink.c @@ -45,7 +45,7 @@ static const char *ext4_encrypted_follow_link(struct dentry *dentry, void **cook cpage = read_mapping_page(inode->i_mapping, 0, NULL); if (IS_ERR(cpage)) return ERR_CAST(cpage); - caddr = kmap(cpage); + caddr = page_address(cpage); caddr[size] = 0; } @@ -75,16 +75,12 @@ static const char *ext4_encrypted_follow_link(struct dentry *dentry, void **cook /* Null-terminate the name */ if (res <= plen) paddr[res] = '\0'; - if (cpage) { - kunmap(cpage); + if (cpage) page_cache_release(cpage); - } return *cookie = paddr; errout: - if (cpage) { - kunmap(cpage); + if (cpage) page_cache_release(cpage); - } kfree(paddr); return ERR_PTR(res); } diff --git a/fs/f2fs/inode.c b/fs/f2fs/inode.c index 97e20decacb4..5528801a5baf 100644 --- a/fs/f2fs/inode.c +++ b/fs/f2fs/inode.c @@ -202,6 +202,7 @@ make_now: inode->i_op = &f2fs_encrypted_symlink_inode_operations; else inode->i_op = &f2fs_symlink_inode_operations; + inode_nohighmem(inode); inode->i_mapping->a_ops = &f2fs_dblock_aops; } else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode) || S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)) { diff --git a/fs/f2fs/namei.c b/fs/f2fs/namei.c index 2c32110f9fc0..484df6850747 100644 --- a/fs/f2fs/namei.c +++ b/fs/f2fs/namei.c @@ -351,6 +351,7 @@ static int f2fs_symlink(struct inode *dir, struct dentry *dentry, inode->i_op = &f2fs_encrypted_symlink_inode_operations; else inode->i_op = &f2fs_symlink_inode_operations; + inode_nohighmem(inode); inode->i_mapping->a_ops = &f2fs_dblock_aops; f2fs_lock_op(sbi); @@ -942,7 +943,7 @@ static const char *f2fs_encrypted_follow_link(struct dentry *dentry, void **cook cpage = read_mapping_page(inode->i_mapping, 0, NULL); if (IS_ERR(cpage)) return ERR_CAST(cpage); - caddr = kmap(cpage); + caddr = page_address(cpage); caddr[size] = 0; /* Symlink is encrypted */ @@ -982,13 +983,11 @@ static const char *f2fs_encrypted_follow_link(struct dentry *dentry, void **cook /* Null-terminate the name */ paddr[res] = '\0'; - kunmap(cpage); page_cache_release(cpage); return *cookie = paddr; errout: kfree(cstr.name); f2fs_fname_crypto_free_buffer(&pstr); - kunmap(cpage); page_cache_release(cpage); return ERR_PTR(res); } diff --git a/fs/freevxfs/vxfs_inode.c b/fs/freevxfs/vxfs_inode.c index ef73ed674a27..3e2ccade61ed 100644 --- a/fs/freevxfs/vxfs_inode.c +++ b/fs/freevxfs/vxfs_inode.c @@ -326,6 +326,7 @@ vxfs_iget(struct super_block *sbp, ino_t ino) } else if (S_ISLNK(ip->i_mode)) { if (!VXFS_ISIMMED(vip)) { ip->i_op = &page_symlink_inode_operations; + inode_nohighmem(ip); ip->i_mapping->a_ops = &vxfs_aops; } else { ip->i_op = &simple_symlink_inode_operations; diff --git a/fs/hfsplus/inode.c b/fs/hfsplus/inode.c index 6dd107d7421e..19b33f8151f1 100644 --- a/fs/hfsplus/inode.c +++ b/fs/hfsplus/inode.c @@ -403,6 +403,7 @@ struct inode *hfsplus_new_inode(struct super_block *sb, umode_t mode) } else if (S_ISLNK(inode->i_mode)) { sbi->file_count++; inode->i_op = &page_symlink_inode_operations; + inode_nohighmem(inode); inode->i_mapping->a_ops = &hfsplus_aops; hip->clump_blocks = 1; } else @@ -526,6 +527,7 @@ int hfsplus_cat_read_inode(struct inode *inode, struct hfs_find_data *fd) inode->i_mapping->a_ops = &hfsplus_aops; } else if (S_ISLNK(inode->i_mode)) { inode->i_op = &page_symlink_inode_operations; + inode_nohighmem(inode); inode->i_mapping->a_ops = &hfsplus_aops; } else { init_special_inode(inode, inode->i_mode, diff --git a/fs/hpfs/inode.c b/fs/hpfs/inode.c index 933c73780813..1f3c6d76200b 100644 --- a/fs/hpfs/inode.c +++ b/fs/hpfs/inode.c @@ -77,6 +77,7 @@ void hpfs_read_inode(struct inode *i) kfree(ea); i->i_mode = S_IFLNK | 0777; i->i_op = &page_symlink_inode_operations; + inode_nohighmem(i); i->i_data.a_ops = &hpfs_symlink_aops; set_nlink(i, 1); i->i_size = ea_size; diff --git a/fs/hpfs/namei.c b/fs/hpfs/namei.c index ae4d5a1fa4c9..506765afa1a3 100644 --- a/fs/hpfs/namei.c +++ b/fs/hpfs/namei.c @@ -332,6 +332,7 @@ static int hpfs_symlink(struct inode *dir, struct dentry *dentry, const char *sy result->i_blocks = 1; set_nlink(result, 1); result->i_size = strlen(symlink); + inode_nohighmem(result); result->i_op = &page_symlink_inode_operations; result->i_data.a_ops = &hpfs_symlink_aops; @@ -500,7 +501,7 @@ out: static int hpfs_symlink_readpage(struct file *file, struct page *page) { - char *link = kmap(page); + char *link = page_address(page); struct inode *i = page->mapping->host; struct fnode *fnode; struct buffer_head *bh; @@ -516,14 +517,12 @@ static int hpfs_symlink_readpage(struct file *file, struct page *page) goto fail; hpfs_unlock(i->i_sb); SetPageUptodate(page); - kunmap(page); unlock_page(page); return 0; fail: hpfs_unlock(i->i_sb); SetPageError(page); - kunmap(page); unlock_page(page); return err; } diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c index de4bdfac0cec..d8f51ee8126b 100644 --- a/fs/hugetlbfs/inode.c +++ b/fs/hugetlbfs/inode.c @@ -760,6 +760,7 @@ static struct inode *hugetlbfs_get_inode(struct super_block *sb, break; case S_IFLNK: inode->i_op = &page_symlink_inode_operations; + inode_nohighmem(inode); break; } lockdep_annotate_inode_mutex_key(inode); diff --git a/fs/inode.c b/fs/inode.c index 1be5f9003eb3..5bb85a064ce7 100644 --- a/fs/inode.c +++ b/fs/inode.c @@ -2028,3 +2028,9 @@ void inode_set_flags(struct inode *inode, unsigned int flags, new_flags) != old_flags)); } EXPORT_SYMBOL(inode_set_flags); + +void inode_nohighmem(struct inode *inode) +{ + mapping_set_gfp_mask(inode->i_mapping, GFP_USER); +} +EXPORT_SYMBOL(inode_nohighmem); diff --git a/fs/isofs/inode.c b/fs/isofs/inode.c index d67a16f2a45d..61abdc4920da 100644 --- a/fs/isofs/inode.c +++ b/fs/isofs/inode.c @@ -1417,6 +1417,7 @@ static int isofs_read_inode(struct inode *inode, int relocated) inode->i_fop = &isofs_dir_operations; } else if (S_ISLNK(inode->i_mode)) { inode->i_op = &page_symlink_inode_operations; + inode_nohighmem(inode); inode->i_data.a_ops = &isofs_symlink_aops; } else /* XXX - parse_rock_ridge_inode() had already set i_rdev. */ diff --git a/fs/isofs/rock.c b/fs/isofs/rock.c index 735d7522a3a9..5384ceb35b1c 100644 --- a/fs/isofs/rock.c +++ b/fs/isofs/rock.c @@ -687,7 +687,7 @@ static int rock_ridge_symlink_readpage(struct file *file, struct page *page) struct inode *inode = page->mapping->host; struct iso_inode_info *ei = ISOFS_I(inode); struct isofs_sb_info *sbi = ISOFS_SB(inode->i_sb); - char *link = kmap(page); + char *link = page_address(page); unsigned long bufsize = ISOFS_BUFFER_SIZE(inode); struct buffer_head *bh; char *rpnt = link; @@ -774,7 +774,6 @@ repeat: brelse(bh); *rpnt = '\0'; SetPageUptodate(page); - kunmap(page); unlock_page(page); return 0; @@ -791,7 +790,6 @@ fail: brelse(bh); error: SetPageError(page); - kunmap(page); unlock_page(page); return -EIO; } diff --git a/fs/jfs/inode.c b/fs/jfs/inode.c index 41aa3ca6a6a4..9d9bae63ae2a 100644 --- a/fs/jfs/inode.c +++ b/fs/jfs/inode.c @@ -60,6 +60,7 @@ struct inode *jfs_iget(struct super_block *sb, unsigned long ino) } else if (S_ISLNK(inode->i_mode)) { if (inode->i_size >= IDATASIZE) { inode->i_op = &page_symlink_inode_operations; + inode_nohighmem(inode); inode->i_mapping->a_ops = &jfs_aops; } else { inode->i_op = &jfs_fast_symlink_inode_operations; diff --git a/fs/jfs/namei.c b/fs/jfs/namei.c index 9d7551f5c32a..701f89370de7 100644 --- a/fs/jfs/namei.c +++ b/fs/jfs/namei.c @@ -983,6 +983,7 @@ static int jfs_symlink(struct inode *dip, struct dentry *dentry, jfs_info("jfs_symlink: allocate extent ip:0x%p", ip); ip->i_op = &jfs_symlink_inode_operations; + inode_nohighmem(ip); ip->i_mapping->a_ops = &jfs_aops; /* diff --git a/fs/logfs/dir.c b/fs/logfs/dir.c index 99944a406a29..542468e9bfb4 100644 --- a/fs/logfs/dir.c +++ b/fs/logfs/dir.c @@ -529,6 +529,7 @@ static int logfs_symlink(struct inode *dir, struct dentry *dentry, return PTR_ERR(inode); inode->i_op = &page_symlink_inode_operations; + inode_nohighmem(inode); inode->i_mapping->a_ops = &logfs_reg_aops; return __logfs_create(dir, dentry, inode, target, destlen); diff --git a/fs/logfs/inode.c b/fs/logfs/inode.c index 06baa926a7a0..0fce46d62b9c 100644 --- a/fs/logfs/inode.c +++ b/fs/logfs/inode.c @@ -65,6 +65,7 @@ static void logfs_inode_setops(struct inode *inode) break; case S_IFLNK: inode->i_op = &page_symlink_inode_operations; + inode_nohighmem(inode); inode->i_mapping->a_ops = &logfs_reg_aops; break; case S_IFSOCK: /* fall through */ diff --git a/fs/minix/inode.c b/fs/minix/inode.c index 086cd0a61e80..67a23bfd7303 100644 --- a/fs/minix/inode.c +++ b/fs/minix/inode.c @@ -452,6 +452,7 @@ void minix_set_inode(struct inode *inode, dev_t rdev) inode->i_mapping->a_ops = &minix_aops; } else if (S_ISLNK(inode->i_mode)) { inode->i_op = &minix_symlink_inode_operations; + inode_nohighmem(inode); inode->i_mapping->a_ops = &minix_aops; } else init_special_inode(inode, inode->i_mode, rdev); diff --git a/fs/namei.c b/fs/namei.c index 4bae5cbfaa85..2808958e6c67 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -4527,7 +4527,8 @@ static const char *page_getlink(struct dentry * dentry, void **cookie) if (IS_ERR(page)) return (char*)page; *cookie = page; - kaddr = kmap(page); + BUG_ON(mapping_gfp_mask(mapping) & __GFP_HIGHMEM); + kaddr = page_address(page); nd_terminate_link(kaddr, dentry->d_inode->i_size, PAGE_SIZE - 1); return kaddr; } @@ -4541,7 +4542,6 @@ EXPORT_SYMBOL(page_follow_link_light); void page_put_link(struct inode *unused, void *cookie) { struct page *page = cookie; - kunmap(page); page_cache_release(page); } EXPORT_SYMBOL(page_put_link); @@ -4565,7 +4565,6 @@ int __page_symlink(struct inode *inode, const char *symname, int len, int nofs) struct page *page; void *fsdata; int err; - char *kaddr; unsigned int flags = AOP_FLAG_UNINTERRUPTIBLE; if (nofs) flags |= AOP_FLAG_NOFS; @@ -4576,9 +4575,7 @@ retry: if (err) goto fail; - kaddr = kmap_atomic(page); - memcpy(kaddr, symname, len-1); - kunmap_atomic(kaddr); + memcpy(page_address(page), symname, len-1); err = pagecache_write_end(NULL, mapping, 0, len-1, len-1, page, fsdata); diff --git a/fs/ncpfs/inode.c b/fs/ncpfs/inode.c index 9605a2f63549..bb856f7e05fd 100644 --- a/fs/ncpfs/inode.c +++ b/fs/ncpfs/inode.c @@ -283,6 +283,7 @@ ncp_iget(struct super_block *sb, struct ncp_entry_info *info) #if defined(CONFIG_NCPFS_EXTRAS) || defined(CONFIG_NCPFS_NFS_NS) } else if (S_ISLNK(inode->i_mode)) { inode->i_op = &ncp_symlink_inode_operations; + inode_nohighmem(inode); inode->i_data.a_ops = &ncp_symlink_aops; #endif } else { diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c index 31b0a52223a7..ae9aa0b8155c 100644 --- a/fs/nfs/inode.c +++ b/fs/nfs/inode.c @@ -408,9 +408,10 @@ nfs_fhget(struct super_block *sb, struct nfs_fh *fh, struct nfs_fattr *fattr, st inode->i_fop = NULL; inode->i_flags |= S_AUTOMOUNT; } - } else if (S_ISLNK(inode->i_mode)) + } else if (S_ISLNK(inode->i_mode)) { inode->i_op = &nfs_symlink_inode_operations; - else + inode_nohighmem(inode); + } else init_special_inode(inode, inode->i_mode, fattr->rdev); memset(&inode->i_atime, 0, sizeof(inode->i_atime)); diff --git a/fs/nfs/symlink.c b/fs/nfs/symlink.c index b6de433da5db..abd93bf015d6 100644 --- a/fs/nfs/symlink.c +++ b/fs/nfs/symlink.c @@ -56,7 +56,7 @@ static const char *nfs_follow_link(struct dentry *dentry, void **cookie) if (IS_ERR(page)) return ERR_CAST(page); *cookie = page; - return kmap(page); + return page_address(page); } /* diff --git a/fs/nilfs2/inode.c b/fs/nilfs2/inode.c index ac2f64943ff4..10b22527a617 100644 --- a/fs/nilfs2/inode.c +++ b/fs/nilfs2/inode.c @@ -510,6 +510,7 @@ static int __nilfs_read_inode(struct super_block *sb, inode->i_mapping->a_ops = &nilfs_aops; } else if (S_ISLNK(inode->i_mode)) { inode->i_op = &nilfs_symlink_inode_operations; + inode_nohighmem(inode); inode->i_mapping->a_ops = &nilfs_aops; } else { inode->i_op = &nilfs_special_inode_operations; diff --git a/fs/nilfs2/namei.c b/fs/nilfs2/namei.c index c9a1a491aa91..90b3ba960b9b 100644 --- a/fs/nilfs2/namei.c +++ b/fs/nilfs2/namei.c @@ -161,6 +161,7 @@ static int nilfs_symlink(struct inode *dir, struct dentry *dentry, /* slow symlink */ inode->i_op = &nilfs_symlink_inode_operations; + inode_nohighmem(inode); inode->i_mapping->a_ops = &nilfs_aops; err = page_symlink(inode, symname, l); if (err) diff --git a/fs/ocfs2/inode.c b/fs/ocfs2/inode.c index 8f87e05ee25d..97a563bab9a8 100644 --- a/fs/ocfs2/inode.c +++ b/fs/ocfs2/inode.c @@ -361,6 +361,7 @@ void ocfs2_populate_inode(struct inode *inode, struct ocfs2_dinode *fe, break; case S_IFLNK: inode->i_op = &ocfs2_symlink_inode_operations; + inode_nohighmem(inode); i_size_write(inode, le64_to_cpu(fe->i_size)); break; default: diff --git a/fs/ocfs2/namei.c b/fs/ocfs2/namei.c index a03f6f433075..2efe8afc82c5 100644 --- a/fs/ocfs2/namei.c +++ b/fs/ocfs2/namei.c @@ -1960,6 +1960,7 @@ static int ocfs2_symlink(struct inode *dir, inode->i_rdev = 0; newsize = l - 1; inode->i_op = &ocfs2_symlink_inode_operations; + inode_nohighmem(inode); if (l > ocfs2_fast_symlink_chars(sb)) { u32 offset = 0; diff --git a/fs/qnx4/inode.c b/fs/qnx4/inode.c index c4bcb778886e..f37b3deb01b4 100644 --- a/fs/qnx4/inode.c +++ b/fs/qnx4/inode.c @@ -316,6 +316,7 @@ struct inode *qnx4_iget(struct super_block *sb, unsigned long ino) inode->i_fop = &qnx4_dir_operations; } else if (S_ISLNK(inode->i_mode)) { inode->i_op = &page_symlink_inode_operations; + inode_nohighmem(inode); inode->i_mapping->a_ops = &qnx4_aops; qnx4_i(inode)->mmu_private = inode->i_size; } else { diff --git a/fs/qnx6/inode.c b/fs/qnx6/inode.c index 32d2e1a9774c..9728b5499e1d 100644 --- a/fs/qnx6/inode.c +++ b/fs/qnx6/inode.c @@ -582,6 +582,7 @@ struct inode *qnx6_iget(struct super_block *sb, unsigned ino) inode->i_mapping->a_ops = &qnx6_aops; } else if (S_ISLNK(inode->i_mode)) { inode->i_op = &page_symlink_inode_operations; + inode_nohighmem(inode); inode->i_mapping->a_ops = &qnx6_aops; } else init_special_inode(inode, inode->i_mode, 0); diff --git a/fs/ramfs/inode.c b/fs/ramfs/inode.c index 889d558b4e05..38981b037524 100644 --- a/fs/ramfs/inode.c +++ b/fs/ramfs/inode.c @@ -79,6 +79,7 @@ struct inode *ramfs_get_inode(struct super_block *sb, break; case S_IFLNK: inode->i_op = &page_symlink_inode_operations; + inode_nohighmem(inode); break; } } diff --git a/fs/reiserfs/inode.c b/fs/reiserfs/inode.c index 3d8e7e671d5b..ae9e5b308cf9 100644 --- a/fs/reiserfs/inode.c +++ b/fs/reiserfs/inode.c @@ -1361,6 +1361,7 @@ static void init_inode(struct inode *inode, struct treepath *path) inode->i_fop = &reiserfs_dir_operations; } else if (S_ISLNK(inode->i_mode)) { inode->i_op = &reiserfs_symlink_inode_operations; + inode_nohighmem(inode); inode->i_mapping->a_ops = &reiserfs_address_space_operations; } else { inode->i_blocks = 0; diff --git a/fs/reiserfs/namei.c b/fs/reiserfs/namei.c index 47f96988fdd4..4fc2326fac03 100644 --- a/fs/reiserfs/namei.c +++ b/fs/reiserfs/namei.c @@ -1170,6 +1170,7 @@ static int reiserfs_symlink(struct inode *parent_dir, reiserfs_update_inode_transaction(parent_dir); inode->i_op = &reiserfs_symlink_inode_operations; + inode_nohighmem(inode); inode->i_mapping->a_ops = &reiserfs_address_space_operations; retval = reiserfs_add_entry(&th, parent_dir, dentry->d_name.name, diff --git a/fs/romfs/super.c b/fs/romfs/super.c index 268733cda397..bb894e78a821 100644 --- a/fs/romfs/super.c +++ b/fs/romfs/super.c @@ -360,6 +360,7 @@ static struct inode *romfs_iget(struct super_block *sb, unsigned long pos) break; case ROMFH_SYM: i->i_op = &page_symlink_inode_operations; + inode_nohighmem(i); i->i_data.a_ops = &romfs_aops; mode |= S_IRWXUGO; break; diff --git a/fs/squashfs/inode.c b/fs/squashfs/inode.c index a1ce5ce60632..0927b1e80ab6 100644 --- a/fs/squashfs/inode.c +++ b/fs/squashfs/inode.c @@ -41,6 +41,7 @@ #include #include #include +#include #include "squashfs_fs.h" #include "squashfs_fs_sb.h" @@ -291,6 +292,7 @@ int squashfs_read_inode(struct inode *inode, long long ino) set_nlink(inode, le32_to_cpu(sqsh_ino->nlink)); inode->i_size = le32_to_cpu(sqsh_ino->symlink_size); inode->i_op = &squashfs_symlink_inode_ops; + inode_nohighmem(inode); inode->i_data.a_ops = &squashfs_symlink_aops; inode->i_mode |= S_IFLNK; squashfs_i(inode)->start = block; diff --git a/fs/sysv/inode.c b/fs/sysv/inode.c index 02fa1dcc5969..ef8bcdb80aca 100644 --- a/fs/sysv/inode.c +++ b/fs/sysv/inode.c @@ -163,6 +163,7 @@ void sysv_set_inode(struct inode *inode, dev_t rdev) inode->i_mapping->a_ops = &sysv_aops; } else if (S_ISLNK(inode->i_mode)) { inode->i_op = &sysv_symlink_inode_operations; + inode_nohighmem(inode); inode->i_mapping->a_ops = &sysv_aops; } else init_special_inode(inode, inode->i_mode, rdev); diff --git a/fs/udf/inode.c b/fs/udf/inode.c index 8675c2b53a71..055746350d16 100644 --- a/fs/udf/inode.c +++ b/fs/udf/inode.c @@ -1541,6 +1541,7 @@ reread: case ICBTAG_FILE_TYPE_SYMLINK: inode->i_data.a_ops = &udf_symlink_aops; inode->i_op = &page_symlink_inode_operations; + inode_nohighmem(inode); inode->i_mode = S_IFLNK | S_IRWXUGO; break; case ICBTAG_FILE_TYPE_MAIN: diff --git a/fs/udf/namei.c b/fs/udf/namei.c index d0e6de1d148c..42eafb91f7ff 100644 --- a/fs/udf/namei.c +++ b/fs/udf/namei.c @@ -922,6 +922,7 @@ static int udf_symlink(struct inode *dir, struct dentry *dentry, inode->i_data.a_ops = &udf_symlink_aops; inode->i_op = &page_symlink_inode_operations; + inode_nohighmem(inode); if (iinfo->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB) { struct kernel_lb_addr eloc; diff --git a/fs/udf/symlink.c b/fs/udf/symlink.c index 862535b3ba58..8d619773056b 100644 --- a/fs/udf/symlink.c +++ b/fs/udf/symlink.c @@ -107,7 +107,7 @@ static int udf_symlink_filler(struct file *file, struct page *page) struct buffer_head *bh = NULL; unsigned char *symlink; int err; - unsigned char *p = kmap(page); + unsigned char *p = page_address(page); struct udf_inode_info *iinfo; uint32_t pos; @@ -141,7 +141,6 @@ static int udf_symlink_filler(struct file *file, struct page *page) up_read(&iinfo->i_data_sem); SetPageUptodate(page); - kunmap(page); unlock_page(page); return 0; @@ -149,7 +148,6 @@ out_unlock_inode: up_read(&iinfo->i_data_sem); SetPageError(page); out_unmap: - kunmap(page); unlock_page(page); return err; } diff --git a/fs/ufs/inode.c b/fs/ufs/inode.c index 737160a7b819..d897e169ab9c 100644 --- a/fs/ufs/inode.c +++ b/fs/ufs/inode.c @@ -533,6 +533,7 @@ static void ufs_set_inode_ops(struct inode *inode) } else { inode->i_mapping->a_ops = &ufs_aops; inode->i_op = &page_symlink_inode_operations; + inode_nohighmem(inode); } } else init_special_inode(inode, inode->i_mode, diff --git a/fs/ufs/namei.c b/fs/ufs/namei.c index 24b0cbd2d917..acf4a3b61b81 100644 --- a/fs/ufs/namei.c +++ b/fs/ufs/namei.c @@ -124,6 +124,7 @@ static int ufs_symlink (struct inode * dir, struct dentry * dentry, if (l > UFS_SB(sb)->s_uspi->s_maxsymlinklen) { /* slow symlink */ inode->i_op = &page_symlink_inode_operations; + inode_nohighmem(inode); inode->i_mapping->a_ops = &ufs_aops; err = page_symlink(inode, symname, l); if (err) diff --git a/include/linux/fs.h b/include/linux/fs.h index 3aa514254161..dfeda44b9ba4 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -3025,5 +3025,6 @@ static inline bool dir_relax(struct inode *inode) } extern bool path_noexec(const struct path *path); +extern void inode_nohighmem(struct inode *inode); #endif /* _LINUX_FS_H */ diff --git a/mm/shmem.c b/mm/shmem.c index 9187eee4128b..64bf5acb49fe 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -2444,7 +2444,6 @@ static int shmem_symlink(struct inode *dir, struct dentry *dentry, const char *s int len; struct inode *inode; struct page *page; - char *kaddr; struct shmem_inode_info *info; len = strlen(symname) + 1; @@ -2483,9 +2482,8 @@ static int shmem_symlink(struct inode *dir, struct dentry *dentry, const char *s } inode->i_mapping->a_ops = &shmem_aops; inode->i_op = &shmem_symlink_inode_operations; - kaddr = kmap_atomic(page); - memcpy(kaddr, symname, len); - kunmap_atomic(kaddr); + inode_nohighmem(inode); + memcpy(page_address(page), symname, len); SetPageUptodate(page); set_page_dirty(page); unlock_page(page); @@ -2506,13 +2504,12 @@ static const char *shmem_follow_link(struct dentry *dentry, void **cookie) return ERR_PTR(error); unlock_page(page); *cookie = page; - return kmap(page); + return page_address(page); } static void shmem_put_link(struct inode *unused, void *cookie) { struct page *page = cookie; - kunmap(page); mark_page_accessed(page); page_cache_release(page); } -- cgit v1.2.3 From 6b2553918d8b4e6de9853fd6315bec7271a2e592 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Tue, 17 Nov 2015 10:20:54 -0500 Subject: replace ->follow_link() with new method that could stay in RCU mode new method: ->get_link(); replacement of ->follow_link(). The differences are: * inode and dentry are passed separately * might be called both in RCU and non-RCU mode; the former is indicated by passing it a NULL dentry. * when called that way it isn't allowed to block and should return ERR_PTR(-ECHILD) if it needs to be called in non-RCU mode. It's a flagday change - the old method is gone, all in-tree instances converted. Conversion isn't hard; said that, so far very few instances do not immediately bail out when called in RCU mode. That'll change in the next commits. Signed-off-by: Al Viro --- Documentation/filesystems/Locking | 4 +-- Documentation/filesystems/porting | 6 ++++ drivers/staging/lustre/lustre/llite/symlink.c | 8 +++-- fs/9p/vfs_inode.c | 17 +++++++--- fs/9p/vfs_inode_dotl.c | 14 ++++++--- fs/affs/symlink.c | 4 +-- fs/autofs4/symlink.c | 13 +++++--- fs/btrfs/inode.c | 2 +- fs/ceph/inode.c | 2 +- fs/cifs/cifsfs.c | 2 +- fs/cifs/cifsfs.h | 4 +-- fs/cifs/link.c | 6 ++-- fs/coda/cnode.c | 2 +- fs/configfs/symlink.c | 11 +++++-- fs/dcache.c | 2 +- fs/ecryptfs/inode.c | 12 +++++-- fs/ext2/symlink.c | 4 +-- fs/ext4/symlink.c | 13 +++++--- fs/f2fs/namei.c | 16 ++++++---- fs/fuse/dir.c | 9 ++++-- fs/gfs2/inode.c | 15 ++++++--- fs/hostfs/hostfs_kern.c | 10 ++++-- fs/jffs2/symlink.c | 2 +- fs/jfs/symlink.c | 4 +-- fs/kernfs/symlink.c | 11 +++++-- fs/libfs.c | 9 +++--- fs/minix/inode.c | 2 +- fs/namei.c | 45 +++++++++++++++++---------- fs/ncpfs/inode.c | 2 +- fs/nfs/symlink.c | 9 ++++-- fs/nilfs2/namei.c | 2 +- fs/ocfs2/symlink.c | 2 +- fs/overlayfs/inode.c | 12 ++++--- fs/proc/base.c | 22 +++++++------ fs/proc/inode.c | 7 +++-- fs/proc/namespaces.c | 9 ++++-- fs/proc/self.c | 9 ++++-- fs/proc/thread_self.c | 9 ++++-- fs/reiserfs/namei.c | 2 +- fs/squashfs/symlink.c | 2 +- fs/sysv/inode.c | 2 +- fs/ubifs/file.c | 2 +- fs/xfs/xfs_iops.c | 8 +++-- include/linux/fs.h | 6 ++-- mm/shmem.c | 12 ++++--- 45 files changed, 234 insertions(+), 132 deletions(-) (limited to 'Documentation/filesystems') diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking index 06d443450f21..4fba54b9fcec 100644 --- a/Documentation/filesystems/Locking +++ b/Documentation/filesystems/Locking @@ -50,7 +50,7 @@ prototypes: int (*rename2) (struct inode *, struct dentry *, struct inode *, struct dentry *, unsigned int); int (*readlink) (struct dentry *, char __user *,int); - const char *(*follow_link) (struct dentry *, void **); + const char *(*get_link) (struct dentry *, struct inode *, void **); void (*put_link) (struct inode *, void *); void (*truncate) (struct inode *); int (*permission) (struct inode *, int, unsigned int); @@ -83,7 +83,7 @@ rmdir: yes (both) (see below) rename: yes (all) (see below) rename2: yes (all) (see below) readlink: no -follow_link: no +get_link: no put_link: no setattr: yes permission: no (may not block if called in rcu-walk mode) diff --git a/Documentation/filesystems/porting b/Documentation/filesystems/porting index 3eb7c35c9698..cf92a8c55594 100644 --- a/Documentation/filesystems/porting +++ b/Documentation/filesystems/porting @@ -509,3 +509,9 @@ in your dentry operations instead. any symlink that might use page_follow_link_light/page_put_link() must have inode_nohighmem(inode) called before anything might start playing with its pagecache. +-- +[mandatory] + ->follow_link() is replaced with ->get_link(); same API, except that + * ->get_link() gets inode as a separate argument + * ->get_link() may be called in RCU mode - in that case NULL + dentry is passed diff --git a/drivers/staging/lustre/lustre/llite/symlink.c b/drivers/staging/lustre/lustre/llite/symlink.c index 69b203651905..153fdf908328 100644 --- a/drivers/staging/lustre/lustre/llite/symlink.c +++ b/drivers/staging/lustre/lustre/llite/symlink.c @@ -118,12 +118,14 @@ failed: return rc; } -static const char *ll_follow_link(struct dentry *dentry, void **cookie) +static const char *ll_get_link(struct dentry *dentry, + struct inode *inode, void **cookie) { - struct inode *inode = d_inode(dentry); struct ptlrpc_request *request = NULL; int rc; char *symname = NULL; + if (!dentry) + return ERR_PTR(-ECHILD); CDEBUG(D_VFSTRACE, "VFS Op\n"); ll_inode_size_lock(inode); @@ -149,7 +151,7 @@ static void ll_put_link(struct inode *unused, void *cookie) struct inode_operations ll_fast_symlink_inode_operations = { .readlink = generic_readlink, .setattr = ll_setattr, - .follow_link = ll_follow_link, + .get_link = ll_get_link, .put_link = ll_put_link, .getattr = ll_getattr, .permission = ll_inode_permission, diff --git a/fs/9p/vfs_inode.c b/fs/9p/vfs_inode.c index 699941e90667..8ba5a897fc0a 100644 --- a/fs/9p/vfs_inode.c +++ b/fs/9p/vfs_inode.c @@ -1223,18 +1223,25 @@ ino_t v9fs_qid2ino(struct p9_qid *qid) } /** - * v9fs_vfs_follow_link - follow a symlink path + * v9fs_vfs_get_link - follow a symlink path * @dentry: dentry for symlink + * @inode: inode for symlink * @cookie: place to pass the data to put_link() */ -static const char *v9fs_vfs_follow_link(struct dentry *dentry, void **cookie) +static const char *v9fs_vfs_get_link(struct dentry *dentry, + struct inode *inode, void **cookie) { - struct v9fs_session_info *v9ses = v9fs_dentry2v9ses(dentry); - struct p9_fid *fid = v9fs_fid_lookup(dentry); + struct v9fs_session_info *v9ses; + struct p9_fid *fid; struct p9_wstat *st; char *res; + if (!dentry) + return ERR_PTR(-ECHILD); + + v9ses = v9fs_dentry2v9ses(dentry); + fid = v9fs_fid_lookup(dentry); p9_debug(P9_DEBUG_VFS, "%pd\n", dentry); if (IS_ERR(fid)) @@ -1452,7 +1459,7 @@ static const struct inode_operations v9fs_file_inode_operations = { static const struct inode_operations v9fs_symlink_inode_operations = { .readlink = generic_readlink, - .follow_link = v9fs_vfs_follow_link, + .get_link = v9fs_vfs_get_link, .put_link = kfree_put_link, .getattr = v9fs_vfs_getattr, .setattr = v9fs_vfs_setattr, diff --git a/fs/9p/vfs_inode_dotl.c b/fs/9p/vfs_inode_dotl.c index cb899af1babc..0cc105d804dd 100644 --- a/fs/9p/vfs_inode_dotl.c +++ b/fs/9p/vfs_inode_dotl.c @@ -899,20 +899,26 @@ error: } /** - * v9fs_vfs_follow_link_dotl - follow a symlink path + * v9fs_vfs_get_link_dotl - follow a symlink path * @dentry: dentry for symlink + * @inode: inode for symlink * @cookie: place to pass the data to put_link() */ static const char * -v9fs_vfs_follow_link_dotl(struct dentry *dentry, void **cookie) +v9fs_vfs_get_link_dotl(struct dentry *dentry, + struct inode *inode, void **cookie) { - struct p9_fid *fid = v9fs_fid_lookup(dentry); + struct p9_fid *fid; char *target; int retval; + if (!dentry) + return ERR_PTR(-ECHILD); + p9_debug(P9_DEBUG_VFS, "%pd\n", dentry); + fid = v9fs_fid_lookup(dentry); if (IS_ERR(fid)) return ERR_CAST(fid); retval = p9_client_readlink(fid, &target); @@ -984,7 +990,7 @@ const struct inode_operations v9fs_file_inode_operations_dotl = { const struct inode_operations v9fs_symlink_inode_operations_dotl = { .readlink = generic_readlink, - .follow_link = v9fs_vfs_follow_link_dotl, + .get_link = v9fs_vfs_get_link_dotl, .put_link = kfree_put_link, .getattr = v9fs_vfs_getattr_dotl, .setattr = v9fs_vfs_setattr_dotl, diff --git a/fs/affs/symlink.c b/fs/affs/symlink.c index e3f9dc3ae8cc..39d1194445e1 100644 --- a/fs/affs/symlink.c +++ b/fs/affs/symlink.c @@ -20,7 +20,7 @@ static int affs_symlink_readpage(struct file *file, struct page *page) char c; char lc; - pr_debug("follow_link(ino=%lu)\n", inode->i_ino); + pr_debug("get_link(ino=%lu)\n", inode->i_ino); bh = affs_bread(inode->i_sb, inode->i_ino); if (!bh) @@ -71,7 +71,7 @@ const struct address_space_operations affs_symlink_aops = { const struct inode_operations affs_symlink_inode_operations = { .readlink = generic_readlink, - .follow_link = page_follow_link_light, + .get_link = page_get_link, .put_link = page_put_link, .setattr = affs_notify_change, }; diff --git a/fs/autofs4/symlink.c b/fs/autofs4/symlink.c index da0c33481bc0..39e6f0bdf8e3 100644 --- a/fs/autofs4/symlink.c +++ b/fs/autofs4/symlink.c @@ -12,10 +12,15 @@ #include "autofs_i.h" -static const char *autofs4_follow_link(struct dentry *dentry, void **cookie) +static const char *autofs4_get_link(struct dentry *dentry, + struct inode *inode, void **cookie) { - struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb); - struct autofs_info *ino = autofs4_dentry_ino(dentry); + struct autofs_sb_info *sbi; + struct autofs_info *ino; + if (!dentry) + return ERR_PTR(-ECHILD); + sbi = autofs4_sbi(dentry->d_sb); + ino = autofs4_dentry_ino(dentry); if (ino && !autofs4_oz_mode(sbi)) ino->last_used = jiffies; return d_inode(dentry)->i_private; @@ -23,5 +28,5 @@ static const char *autofs4_follow_link(struct dentry *dentry, void **cookie) const struct inode_operations autofs4_symlink_inode_operations = { .readlink = generic_readlink, - .follow_link = autofs4_follow_link + .get_link = autofs4_get_link }; diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 70f98bfde277..3d4aa69f1e0c 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -10096,7 +10096,7 @@ static const struct inode_operations btrfs_special_inode_operations = { }; static const struct inode_operations btrfs_symlink_inode_operations = { .readlink = generic_readlink, - .follow_link = page_follow_link_light, + .get_link = page_get_link, .put_link = page_put_link, .getattr = btrfs_getattr, .setattr = btrfs_setattr, diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c index 498dcfa2dcdb..da55eb8bcffa 100644 --- a/fs/ceph/inode.c +++ b/fs/ceph/inode.c @@ -1756,7 +1756,7 @@ retry: */ static const struct inode_operations ceph_symlink_iops = { .readlink = generic_readlink, - .follow_link = simple_follow_link, + .get_link = simple_get_link, .setattr = ceph_setattr, .getattr = ceph_getattr, .setxattr = ceph_setxattr, diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c index cbc0f4bca0c0..4593f41678ef 100644 --- a/fs/cifs/cifsfs.c +++ b/fs/cifs/cifsfs.c @@ -900,7 +900,7 @@ const struct inode_operations cifs_file_inode_ops = { const struct inode_operations cifs_symlink_inode_ops = { .readlink = generic_readlink, - .follow_link = cifs_follow_link, + .get_link = cifs_get_link, .put_link = kfree_put_link, .permission = cifs_permission, /* BB add the following two eventually */ diff --git a/fs/cifs/cifsfs.h b/fs/cifs/cifsfs.h index c3cc1609025f..6886328cf3c4 100644 --- a/fs/cifs/cifsfs.h +++ b/fs/cifs/cifsfs.h @@ -120,9 +120,7 @@ extern struct vfsmount *cifs_dfs_d_automount(struct path *path); #endif /* Functions related to symlinks */ -extern const char *cifs_follow_link(struct dentry *direntry, void **cookie); -extern int cifs_readlink(struct dentry *direntry, char __user *buffer, - int buflen); +extern const char *cifs_get_link(struct dentry *, struct inode *, void **); extern int cifs_symlink(struct inode *inode, struct dentry *direntry, const char *symname); extern int cifs_removexattr(struct dentry *, const char *); diff --git a/fs/cifs/link.c b/fs/cifs/link.c index e3548f73bdea..6f2439b508b5 100644 --- a/fs/cifs/link.c +++ b/fs/cifs/link.c @@ -627,9 +627,8 @@ cifs_hl_exit: } const char * -cifs_follow_link(struct dentry *direntry, void **cookie) +cifs_get_link(struct dentry *direntry, struct inode *inode, void **cookie) { - struct inode *inode = d_inode(direntry); int rc = -ENOMEM; unsigned int xid; char *full_path = NULL; @@ -639,6 +638,9 @@ cifs_follow_link(struct dentry *direntry, void **cookie) struct cifs_tcon *tcon; struct TCP_Server_Info *server; + if (!direntry) + return ERR_PTR(-ECHILD); + xid = get_xid(); tlink = cifs_sb_tlink(cifs_sb); diff --git a/fs/coda/cnode.c b/fs/coda/cnode.c index dd6a79ef4750..f18139c7690a 100644 --- a/fs/coda/cnode.c +++ b/fs/coda/cnode.c @@ -18,7 +18,7 @@ static inline int coda_fideq(struct CodaFid *fid1, struct CodaFid *fid2) static const struct inode_operations coda_symlink_inode_operations = { .readlink = generic_readlink, - .follow_link = page_follow_link_light, + .get_link = page_get_link, .put_link = page_put_link, .setattr = coda_setattr, }; diff --git a/fs/configfs/symlink.c b/fs/configfs/symlink.c index ec5c8325b503..b91c01ebb688 100644 --- a/fs/configfs/symlink.c +++ b/fs/configfs/symlink.c @@ -279,11 +279,16 @@ static int configfs_getlink(struct dentry *dentry, char * path) } -static const char *configfs_follow_link(struct dentry *dentry, void **cookie) +static const char *configfs_get_link(struct dentry *dentry, + struct inode *inode, void **cookie) { - unsigned long page = get_zeroed_page(GFP_KERNEL); + unsigned long page; int error; + if (!dentry) + return ERR_PTR(-ECHILD); + + page = get_zeroed_page(GFP_KERNEL); if (!page) return ERR_PTR(-ENOMEM); @@ -297,7 +302,7 @@ static const char *configfs_follow_link(struct dentry *dentry, void **cookie) } const struct inode_operations configfs_symlink_inode_operations = { - .follow_link = configfs_follow_link, + .get_link = configfs_get_link, .readlink = generic_readlink, .put_link = free_page_put_link, .setattr = configfs_setattr, diff --git a/fs/dcache.c b/fs/dcache.c index 5c33aeb0f68f..d27f0909d9f6 100644 --- a/fs/dcache.c +++ b/fs/dcache.c @@ -1734,7 +1734,7 @@ static unsigned d_flags_for_inode(struct inode *inode) } if (unlikely(!(inode->i_opflags & IOP_NOFOLLOW))) { - if (unlikely(inode->i_op->follow_link)) { + if (unlikely(inode->i_op->get_link)) { add_flags = DCACHE_SYMLINK_TYPE; goto type_determined; } diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c index e2e47ba5d313..5a05559cb23d 100644 --- a/fs/ecryptfs/inode.c +++ b/fs/ecryptfs/inode.c @@ -674,10 +674,16 @@ out: return rc ? ERR_PTR(rc) : buf; } -static const char *ecryptfs_follow_link(struct dentry *dentry, void **cookie) +static const char *ecryptfs_get_link(struct dentry *dentry, + struct inode *inode, void **cookie) { size_t len; - char *buf = ecryptfs_readlink_lower(dentry, &len); + char *buf; + + if (!dentry) + return ERR_PTR(-ECHILD); + + buf = ecryptfs_readlink_lower(dentry, &len); if (IS_ERR(buf)) return buf; fsstack_copy_attr_atime(d_inode(dentry), @@ -1095,7 +1101,7 @@ out: const struct inode_operations ecryptfs_symlink_iops = { .readlink = generic_readlink, - .follow_link = ecryptfs_follow_link, + .get_link = ecryptfs_get_link, .put_link = kfree_put_link, .permission = ecryptfs_permission, .setattr = ecryptfs_setattr, diff --git a/fs/ext2/symlink.c b/fs/ext2/symlink.c index ae17179f3810..46905119a27c 100644 --- a/fs/ext2/symlink.c +++ b/fs/ext2/symlink.c @@ -22,7 +22,7 @@ const struct inode_operations ext2_symlink_inode_operations = { .readlink = generic_readlink, - .follow_link = page_follow_link_light, + .get_link = page_get_link, .put_link = page_put_link, .setattr = ext2_setattr, #ifdef CONFIG_EXT2_FS_XATTR @@ -35,7 +35,7 @@ const struct inode_operations ext2_symlink_inode_operations = { const struct inode_operations ext2_fast_symlink_inode_operations = { .readlink = generic_readlink, - .follow_link = simple_follow_link, + .get_link = simple_get_link, .setattr = ext2_setattr, #ifdef CONFIG_EXT2_FS_XATTR .setxattr = generic_setxattr, diff --git a/fs/ext4/symlink.c b/fs/ext4/symlink.c index 0e6dc44c5ebf..3b4bfe2ebd75 100644 --- a/fs/ext4/symlink.c +++ b/fs/ext4/symlink.c @@ -23,17 +23,20 @@ #include "xattr.h" #ifdef CONFIG_EXT4_FS_ENCRYPTION -static const char *ext4_encrypted_follow_link(struct dentry *dentry, void **cookie) +static const char *ext4_encrypted_get_link(struct dentry *dentry, + struct inode *inode, void **cookie) { struct page *cpage = NULL; char *caddr, *paddr = NULL; struct ext4_str cstr, pstr; - struct inode *inode = d_inode(dentry); struct ext4_encrypted_symlink_data *sd; loff_t size = min_t(loff_t, i_size_read(inode), PAGE_SIZE - 1); int res; u32 plen, max_size = inode->i_sb->s_blocksize; + if (!dentry) + return ERR_PTR(-ECHILD); + res = ext4_get_encryption_info(inode); if (res) return ERR_PTR(res); @@ -87,7 +90,7 @@ errout: const struct inode_operations ext4_encrypted_symlink_inode_operations = { .readlink = generic_readlink, - .follow_link = ext4_encrypted_follow_link, + .get_link = ext4_encrypted_get_link, .put_link = kfree_put_link, .setattr = ext4_setattr, .setxattr = generic_setxattr, @@ -99,7 +102,7 @@ const struct inode_operations ext4_encrypted_symlink_inode_operations = { const struct inode_operations ext4_symlink_inode_operations = { .readlink = generic_readlink, - .follow_link = page_follow_link_light, + .get_link = page_get_link, .put_link = page_put_link, .setattr = ext4_setattr, .setxattr = generic_setxattr, @@ -110,7 +113,7 @@ const struct inode_operations ext4_symlink_inode_operations = { const struct inode_operations ext4_fast_symlink_inode_operations = { .readlink = generic_readlink, - .follow_link = simple_follow_link, + .get_link = simple_get_link, .setattr = ext4_setattr, .setxattr = generic_setxattr, .getxattr = generic_getxattr, diff --git a/fs/f2fs/namei.c b/fs/f2fs/namei.c index 484df6850747..2a8d84b727ce 100644 --- a/fs/f2fs/namei.c +++ b/fs/f2fs/namei.c @@ -315,9 +315,10 @@ fail: return err; } -static const char *f2fs_follow_link(struct dentry *dentry, void **cookie) +static const char *f2fs_get_link(struct dentry *dentry, + struct inode *inode, void **cookie) { - const char *link = page_follow_link_light(dentry, cookie); + const char *link = page_get_link(dentry, inode, cookie); if (!IS_ERR(link) && !*link) { /* this is broken symlink case */ page_put_link(NULL, *cookie); @@ -924,18 +925,21 @@ static int f2fs_rename2(struct inode *old_dir, struct dentry *old_dentry, } #ifdef CONFIG_F2FS_FS_ENCRYPTION -static const char *f2fs_encrypted_follow_link(struct dentry *dentry, void **cookie) +static const char *f2fs_encrypted_get_link(struct dentry *dentry, + struct inode *inode, void **cookie) { struct page *cpage = NULL; char *caddr, *paddr = NULL; struct f2fs_str cstr; struct f2fs_str pstr = FSTR_INIT(NULL, 0); - struct inode *inode = d_inode(dentry); struct f2fs_encrypted_symlink_data *sd; loff_t size = min_t(loff_t, i_size_read(inode), PAGE_SIZE - 1); u32 max_size = inode->i_sb->s_blocksize; int res; + if (!dentry) + return ERR_PTR(-ECHILD); + res = f2fs_get_encryption_info(inode); if (res) return ERR_PTR(res); @@ -994,7 +998,7 @@ errout: const struct inode_operations f2fs_encrypted_symlink_inode_operations = { .readlink = generic_readlink, - .follow_link = f2fs_encrypted_follow_link, + .get_link = f2fs_encrypted_get_link, .put_link = kfree_put_link, .getattr = f2fs_getattr, .setattr = f2fs_setattr, @@ -1030,7 +1034,7 @@ const struct inode_operations f2fs_dir_inode_operations = { const struct inode_operations f2fs_symlink_inode_operations = { .readlink = generic_readlink, - .follow_link = f2fs_follow_link, + .get_link = f2fs_get_link, .put_link = page_put_link, .getattr = f2fs_getattr, .setattr = f2fs_setattr, diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c index 5e2e08712d3b..148e8ef7c541 100644 --- a/fs/fuse/dir.c +++ b/fs/fuse/dir.c @@ -1365,14 +1365,17 @@ static int fuse_readdir(struct file *file, struct dir_context *ctx) return err; } -static const char *fuse_follow_link(struct dentry *dentry, void **cookie) +static const char *fuse_get_link(struct dentry *dentry, + struct inode *inode, void **cookie) { - struct inode *inode = d_inode(dentry); struct fuse_conn *fc = get_fuse_conn(inode); FUSE_ARGS(args); char *link; ssize_t ret; + if (!dentry) + return ERR_PTR(-ECHILD); + link = (char *) __get_free_page(GFP_KERNEL); if (!link) return ERR_PTR(-ENOMEM); @@ -1909,7 +1912,7 @@ static const struct inode_operations fuse_common_inode_operations = { static const struct inode_operations fuse_symlink_inode_operations = { .setattr = fuse_setattr, - .follow_link = fuse_follow_link, + .get_link = fuse_get_link, .put_link = free_page_put_link, .readlink = generic_readlink, .getattr = fuse_getattr, diff --git a/fs/gfs2/inode.c b/fs/gfs2/inode.c index 063fdfcf8275..1095056046cc 100644 --- a/fs/gfs2/inode.c +++ b/fs/gfs2/inode.c @@ -1712,24 +1712,29 @@ static int gfs2_rename2(struct inode *odir, struct dentry *odentry, } /** - * gfs2_follow_link - Follow a symbolic link + * gfs2_get_link - Follow a symbolic link * @dentry: The dentry of the link - * @nd: Data that we pass to vfs_follow_link() + * @inode: The inode of the link + * @cookie: place to store the information for ->put_link() * * This can handle symlinks of any size. * * Returns: 0 on success or error code */ -static const char *gfs2_follow_link(struct dentry *dentry, void **cookie) +static const char *gfs2_get_link(struct dentry *dentry, + struct inode *inode, void **cookie) { - struct gfs2_inode *ip = GFS2_I(d_inode(dentry)); + struct gfs2_inode *ip = GFS2_I(inode); struct gfs2_holder i_gh; struct buffer_head *dibh; unsigned int size; char *buf; int error; + if (!dentry) + return ERR_PTR(-ECHILD); + gfs2_holder_init(ip->i_gl, LM_ST_SHARED, 0, &i_gh); error = gfs2_glock_nq(&i_gh); if (error) { @@ -2132,7 +2137,7 @@ const struct inode_operations gfs2_dir_iops = { const struct inode_operations gfs2_symlink_iops = { .readlink = generic_readlink, - .follow_link = gfs2_follow_link, + .get_link = gfs2_get_link, .put_link = kfree_put_link, .permission = gfs2_permission, .setattr = gfs2_setattr, diff --git a/fs/hostfs/hostfs_kern.c b/fs/hostfs/hostfs_kern.c index 2ac99db3750e..6ce5309ecb7b 100644 --- a/fs/hostfs/hostfs_kern.c +++ b/fs/hostfs/hostfs_kern.c @@ -892,9 +892,13 @@ static const struct inode_operations hostfs_dir_iops = { .setattr = hostfs_setattr, }; -static const char *hostfs_follow_link(struct dentry *dentry, void **cookie) +static const char *hostfs_get_link(struct dentry *dentry, + struct inode *inode, void **cookie) { - char *link = __getname(); + char *link; + if (!dentry) + return ERR_PTR(-ECHILD); + link = __getname(); if (link) { char *path = dentry_name(dentry); int err = -ENOMEM; @@ -922,7 +926,7 @@ static void hostfs_put_link(struct inode *unused, void *cookie) static const struct inode_operations hostfs_link_iops = { .readlink = generic_readlink, - .follow_link = hostfs_follow_link, + .get_link = hostfs_get_link, .put_link = hostfs_put_link, }; diff --git a/fs/jffs2/symlink.c b/fs/jffs2/symlink.c index 8ce2f240125b..2cabd649d4fb 100644 --- a/fs/jffs2/symlink.c +++ b/fs/jffs2/symlink.c @@ -14,7 +14,7 @@ const struct inode_operations jffs2_symlink_inode_operations = { .readlink = generic_readlink, - .follow_link = simple_follow_link, + .get_link = simple_get_link, .setattr = jffs2_setattr, .setxattr = jffs2_setxattr, .getxattr = jffs2_getxattr, diff --git a/fs/jfs/symlink.c b/fs/jfs/symlink.c index 5929e2363cb8..02113282772e 100644 --- a/fs/jfs/symlink.c +++ b/fs/jfs/symlink.c @@ -23,7 +23,7 @@ const struct inode_operations jfs_fast_symlink_inode_operations = { .readlink = generic_readlink, - .follow_link = simple_follow_link, + .get_link = simple_get_link, .setattr = jfs_setattr, .setxattr = jfs_setxattr, .getxattr = jfs_getxattr, @@ -33,7 +33,7 @@ const struct inode_operations jfs_fast_symlink_inode_operations = { const struct inode_operations jfs_symlink_inode_operations = { .readlink = generic_readlink, - .follow_link = page_follow_link_light, + .get_link = page_get_link, .put_link = page_put_link, .setattr = jfs_setattr, .setxattr = jfs_setxattr, diff --git a/fs/kernfs/symlink.c b/fs/kernfs/symlink.c index db272528ab5b..ffae8579045d 100644 --- a/fs/kernfs/symlink.c +++ b/fs/kernfs/symlink.c @@ -112,10 +112,15 @@ static int kernfs_getlink(struct dentry *dentry, char *path) return error; } -static const char *kernfs_iop_follow_link(struct dentry *dentry, void **cookie) +static const char *kernfs_iop_get_link(struct dentry *dentry, + struct inode *inode, void **cookie) { int error = -ENOMEM; - unsigned long page = get_zeroed_page(GFP_KERNEL); + unsigned long page; + + if (!dentry) + return ERR_PTR(-ECHILD); + page = get_zeroed_page(GFP_KERNEL); if (!page) return ERR_PTR(-ENOMEM); error = kernfs_getlink(dentry, (char *)page); @@ -132,7 +137,7 @@ const struct inode_operations kernfs_symlink_iops = { .getxattr = kernfs_iop_getxattr, .listxattr = kernfs_iop_listxattr, .readlink = generic_readlink, - .follow_link = kernfs_iop_follow_link, + .get_link = kernfs_iop_get_link, .put_link = free_page_put_link, .setattr = kernfs_iop_setattr, .getattr = kernfs_iop_getattr, diff --git a/fs/libfs.c b/fs/libfs.c index c7cbfb092e94..8dc37fc4b6df 100644 --- a/fs/libfs.c +++ b/fs/libfs.c @@ -1092,14 +1092,15 @@ simple_nosetlease(struct file *filp, long arg, struct file_lock **flp, } EXPORT_SYMBOL(simple_nosetlease); -const char *simple_follow_link(struct dentry *dentry, void **cookie) +const char *simple_get_link(struct dentry *dentry, struct inode *inode, + void **cookie) { - return d_inode(dentry)->i_link; + return inode->i_link; } -EXPORT_SYMBOL(simple_follow_link); +EXPORT_SYMBOL(simple_get_link); const struct inode_operations simple_symlink_inode_operations = { - .follow_link = simple_follow_link, + .get_link = simple_get_link, .readlink = generic_readlink }; EXPORT_SYMBOL(simple_symlink_inode_operations); diff --git a/fs/minix/inode.c b/fs/minix/inode.c index 67a23bfd7303..3cce709a8729 100644 --- a/fs/minix/inode.c +++ b/fs/minix/inode.c @@ -435,7 +435,7 @@ static const struct address_space_operations minix_aops = { static const struct inode_operations minix_symlink_inode_operations = { .readlink = generic_readlink, - .follow_link = page_follow_link_light, + .get_link = page_get_link, .put_link = page_put_link, .getattr = minix_getattr, }; diff --git a/fs/namei.c b/fs/namei.c index 2808958e6c67..1da3064311e2 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -842,7 +842,7 @@ static inline void path_to_nameidata(const struct path *path, } /* - * Helper to directly jump to a known parsed path from ->follow_link, + * Helper to directly jump to a known parsed path from ->get_link, * caller must have taken a reference to path beforehand. */ void nd_jump_link(struct path *path) @@ -1005,10 +1005,18 @@ const char *get_link(struct nameidata *nd) res = inode->i_link; if (!res) { if (nd->flags & LOOKUP_RCU) { - if (unlikely(unlazy_walk(nd, NULL, 0))) - return ERR_PTR(-ECHILD); + res = inode->i_op->get_link(NULL, inode, + &last->cookie); + if (res == ERR_PTR(-ECHILD)) { + if (unlikely(unlazy_walk(nd, NULL, 0))) + return ERR_PTR(-ECHILD); + res = inode->i_op->get_link(dentry, inode, + &last->cookie); + } + } else { + res = inode->i_op->get_link(dentry, inode, + &last->cookie); } - res = inode->i_op->follow_link(dentry, &last->cookie); if (IS_ERR_OR_NULL(res)) { last->cookie = NULL; return res; @@ -4495,8 +4503,8 @@ EXPORT_SYMBOL(readlink_copy); /* * A helper for ->readlink(). This should be used *ONLY* for symlinks that - * have ->follow_link() touching nd only in nd_set_link(). Using (or not - * using) it for any given inode is up to filesystem. + * have ->get_link() not calling nd_jump_link(). Using (or not using) it + * for any given inode is up to filesystem. */ int generic_readlink(struct dentry *dentry, char __user *buffer, int buflen) { @@ -4506,7 +4514,7 @@ int generic_readlink(struct dentry *dentry, char __user *buffer, int buflen) int res; if (!link) { - link = inode->i_op->follow_link(dentry, &cookie); + link = inode->i_op->get_link(dentry, inode, &cookie); if (IS_ERR(link)) return PTR_ERR(link); } @@ -4518,26 +4526,27 @@ int generic_readlink(struct dentry *dentry, char __user *buffer, int buflen) EXPORT_SYMBOL(generic_readlink); /* get the link contents into pagecache */ -static const char *page_getlink(struct dentry * dentry, void **cookie) +const char *page_get_link(struct dentry *dentry, struct inode *inode, + void **cookie) { char *kaddr; struct page *page; - struct address_space *mapping = dentry->d_inode->i_mapping; + struct address_space *mapping = inode->i_mapping; + + if (!dentry) + return ERR_PTR(-ECHILD); + page = read_mapping_page(mapping, 0, NULL); if (IS_ERR(page)) return (char*)page; *cookie = page; BUG_ON(mapping_gfp_mask(mapping) & __GFP_HIGHMEM); kaddr = page_address(page); - nd_terminate_link(kaddr, dentry->d_inode->i_size, PAGE_SIZE - 1); + nd_terminate_link(kaddr, inode->i_size, PAGE_SIZE - 1); return kaddr; } -const char *page_follow_link_light(struct dentry *dentry, void **cookie) -{ - return page_getlink(dentry, cookie); -} -EXPORT_SYMBOL(page_follow_link_light); +EXPORT_SYMBOL(page_get_link); void page_put_link(struct inode *unused, void *cookie) { @@ -4549,7 +4558,9 @@ EXPORT_SYMBOL(page_put_link); int page_readlink(struct dentry *dentry, char __user *buffer, int buflen) { void *cookie = NULL; - int res = readlink_copy(buffer, buflen, page_getlink(dentry, &cookie)); + int res = readlink_copy(buffer, buflen, + page_get_link(dentry, d_inode(dentry), + &cookie)); if (cookie) page_put_link(NULL, cookie); return res; @@ -4600,7 +4611,7 @@ EXPORT_SYMBOL(page_symlink); const struct inode_operations page_symlink_inode_operations = { .readlink = generic_readlink, - .follow_link = page_follow_link_light, + .get_link = page_get_link, .put_link = page_put_link, }; EXPORT_SYMBOL(page_symlink_inode_operations); diff --git a/fs/ncpfs/inode.c b/fs/ncpfs/inode.c index bb856f7e05fd..3ab6cdbcde60 100644 --- a/fs/ncpfs/inode.c +++ b/fs/ncpfs/inode.c @@ -244,7 +244,7 @@ static void ncp_set_attr(struct inode *inode, struct ncp_entry_info *nwinfo) #if defined(CONFIG_NCPFS_EXTRAS) || defined(CONFIG_NCPFS_NFS_NS) static const struct inode_operations ncp_symlink_inode_operations = { .readlink = generic_readlink, - .follow_link = page_follow_link_light, + .get_link = page_get_link, .put_link = page_put_link, .setattr = ncp_notify_change, }; diff --git a/fs/nfs/symlink.c b/fs/nfs/symlink.c index abd93bf015d6..8ade8a812607 100644 --- a/fs/nfs/symlink.c +++ b/fs/nfs/symlink.c @@ -42,12 +42,15 @@ error: return -EIO; } -static const char *nfs_follow_link(struct dentry *dentry, void **cookie) +static const char *nfs_get_link(struct dentry *dentry, + struct inode *inode, void **cookie) { - struct inode *inode = d_inode(dentry); struct page *page; void *err; + if (!dentry) + return ERR_PTR(-ECHILD); + err = ERR_PTR(nfs_revalidate_mapping(inode, inode->i_mapping)); if (err) return err; @@ -64,7 +67,7 @@ static const char *nfs_follow_link(struct dentry *dentry, void **cookie) */ const struct inode_operations nfs_symlink_inode_operations = { .readlink = generic_readlink, - .follow_link = nfs_follow_link, + .get_link = nfs_get_link, .put_link = page_put_link, .getattr = nfs_getattr, .setattr = nfs_setattr, diff --git a/fs/nilfs2/namei.c b/fs/nilfs2/namei.c index 90b3ba960b9b..63dddb7d4b18 100644 --- a/fs/nilfs2/namei.c +++ b/fs/nilfs2/namei.c @@ -569,7 +569,7 @@ const struct inode_operations nilfs_special_inode_operations = { const struct inode_operations nilfs_symlink_inode_operations = { .readlink = generic_readlink, - .follow_link = page_follow_link_light, + .get_link = page_get_link, .put_link = page_put_link, .permission = nilfs_permission, }; diff --git a/fs/ocfs2/symlink.c b/fs/ocfs2/symlink.c index 66edce7ecfd7..b4e79bc720f7 100644 --- a/fs/ocfs2/symlink.c +++ b/fs/ocfs2/symlink.c @@ -88,7 +88,7 @@ const struct address_space_operations ocfs2_fast_symlink_aops = { const struct inode_operations ocfs2_symlink_inode_operations = { .readlink = generic_readlink, - .follow_link = page_follow_link_light, + .get_link = page_get_link, .put_link = page_put_link, .getattr = ocfs2_getattr, .setattr = ocfs2_setattr, diff --git a/fs/overlayfs/inode.c b/fs/overlayfs/inode.c index 4060ffde8722..38a0b8b9f8b9 100644 --- a/fs/overlayfs/inode.c +++ b/fs/overlayfs/inode.c @@ -137,17 +137,21 @@ struct ovl_link_data { void *cookie; }; -static const char *ovl_follow_link(struct dentry *dentry, void **cookie) +static const char *ovl_get_link(struct dentry *dentry, + struct inode *inode, void **cookie) { struct dentry *realdentry; struct inode *realinode; struct ovl_link_data *data = NULL; const char *ret; + if (!dentry) + return ERR_PTR(-ECHILD); + realdentry = ovl_dentry_real(dentry); realinode = realdentry->d_inode; - if (WARN_ON(!realinode->i_op->follow_link)) + if (WARN_ON(!realinode->i_op->get_link)) return ERR_PTR(-EPERM); if (realinode->i_op->put_link) { @@ -157,7 +161,7 @@ static const char *ovl_follow_link(struct dentry *dentry, void **cookie) data->realdentry = realdentry; } - ret = realinode->i_op->follow_link(realdentry, cookie); + ret = realinode->i_op->get_link(realdentry, realinode, cookie); if (IS_ERR_OR_NULL(ret)) { kfree(data); return ret; @@ -378,7 +382,7 @@ static const struct inode_operations ovl_file_inode_operations = { static const struct inode_operations ovl_symlink_inode_operations = { .setattr = ovl_setattr, - .follow_link = ovl_follow_link, + .get_link = ovl_get_link, .put_link = ovl_put_link, .readlink = ovl_readlink, .getattr = ovl_getattr, diff --git a/fs/proc/base.c b/fs/proc/base.c index bd3e9e68125b..1a489e2b9768 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -1564,12 +1564,15 @@ static int proc_exe_link(struct dentry *dentry, struct path *exe_path) return -ENOENT; } -static const char *proc_pid_follow_link(struct dentry *dentry, void **cookie) +static const char *proc_pid_get_link(struct dentry *dentry, + struct inode *inode, void **cookie) { - struct inode *inode = d_inode(dentry); struct path path; int error = -EACCES; + if (!dentry) + return ERR_PTR(-ECHILD); + /* Are we allowed to snoop on the tasks file descriptors? */ if (!proc_fd_access_allowed(inode)) goto out; @@ -1630,7 +1633,7 @@ out: const struct inode_operations proc_pid_link_inode_operations = { .readlink = proc_pid_readlink, - .follow_link = proc_pid_follow_link, + .get_link = proc_pid_get_link, .setattr = proc_setattr, }; @@ -1895,7 +1898,7 @@ static const struct dentry_operations tid_map_files_dentry_operations = { .d_delete = pid_delete_dentry, }; -static int proc_map_files_get_link(struct dentry *dentry, struct path *path) +static int map_files_get_link(struct dentry *dentry, struct path *path) { unsigned long vm_start, vm_end; struct vm_area_struct *vma; @@ -1945,20 +1948,21 @@ struct map_files_info { * path to the file in question. */ static const char * -proc_map_files_follow_link(struct dentry *dentry, void **cookie) +proc_map_files_get_link(struct dentry *dentry, + struct inode *inode, void **cookie) { if (!capable(CAP_SYS_ADMIN)) return ERR_PTR(-EPERM); - return proc_pid_follow_link(dentry, NULL); + return proc_pid_get_link(dentry, inode, NULL); } /* - * Identical to proc_pid_link_inode_operations except for follow_link() + * Identical to proc_pid_link_inode_operations except for get_link() */ static const struct inode_operations proc_map_files_link_inode_operations = { .readlink = proc_pid_readlink, - .follow_link = proc_map_files_follow_link, + .get_link = proc_map_files_get_link, .setattr = proc_setattr, }; @@ -1975,7 +1979,7 @@ proc_map_files_instantiate(struct inode *dir, struct dentry *dentry, return -ENOENT; ei = PROC_I(inode); - ei->op.proc_get_link = proc_map_files_get_link; + ei->op.proc_get_link = map_files_get_link; inode->i_op = &proc_map_files_link_inode_operations; inode->i_size = 64; diff --git a/fs/proc/inode.c b/fs/proc/inode.c index bd95b9fdebb0..10360b268794 100644 --- a/fs/proc/inode.c +++ b/fs/proc/inode.c @@ -393,9 +393,10 @@ static const struct file_operations proc_reg_file_ops_no_compat = { }; #endif -static const char *proc_follow_link(struct dentry *dentry, void **cookie) +static const char *proc_get_link(struct dentry *dentry, + struct inode *inode, void **cookie) { - struct proc_dir_entry *pde = PDE(d_inode(dentry)); + struct proc_dir_entry *pde = PDE(inode); if (unlikely(!use_pde(pde))) return ERR_PTR(-EINVAL); *cookie = pde; @@ -409,7 +410,7 @@ static void proc_put_link(struct inode *unused, void *p) const struct inode_operations proc_link_inode_operations = { .readlink = generic_readlink, - .follow_link = proc_follow_link, + .get_link = proc_get_link, .put_link = proc_put_link, }; diff --git a/fs/proc/namespaces.c b/fs/proc/namespaces.c index f6e8354b8cea..63861c15e109 100644 --- a/fs/proc/namespaces.c +++ b/fs/proc/namespaces.c @@ -30,14 +30,17 @@ static const struct proc_ns_operations *ns_entries[] = { &mntns_operations, }; -static const char *proc_ns_follow_link(struct dentry *dentry, void **cookie) +static const char *proc_ns_get_link(struct dentry *dentry, + struct inode *inode, void **cookie) { - struct inode *inode = d_inode(dentry); const struct proc_ns_operations *ns_ops = PROC_I(inode)->ns_ops; struct task_struct *task; struct path ns_path; void *error = ERR_PTR(-EACCES); + if (!dentry) + return ERR_PTR(-ECHILD); + task = get_proc_task(inode); if (!task) return error; @@ -74,7 +77,7 @@ static int proc_ns_readlink(struct dentry *dentry, char __user *buffer, int bufl static const struct inode_operations proc_ns_link_inode_operations = { .readlink = proc_ns_readlink, - .follow_link = proc_ns_follow_link, + .get_link = proc_ns_get_link, .setattr = proc_setattr, }; diff --git a/fs/proc/self.c b/fs/proc/self.c index 113b8d061fc0..9dd0ae6aefdb 100644 --- a/fs/proc/self.c +++ b/fs/proc/self.c @@ -18,12 +18,15 @@ static int proc_self_readlink(struct dentry *dentry, char __user *buffer, return readlink_copy(buffer, buflen, tmp); } -static const char *proc_self_follow_link(struct dentry *dentry, void **cookie) +static const char *proc_self_get_link(struct dentry *dentry, + struct inode *inode, void **cookie) { - struct pid_namespace *ns = dentry->d_sb->s_fs_info; + struct pid_namespace *ns = inode->i_sb->s_fs_info; pid_t tgid = task_tgid_nr_ns(current, ns); char *name; + if (!dentry) + return ERR_PTR(-ECHILD); if (!tgid) return ERR_PTR(-ENOENT); /* 11 for max length of signed int in decimal + NULL term */ @@ -36,7 +39,7 @@ static const char *proc_self_follow_link(struct dentry *dentry, void **cookie) static const struct inode_operations proc_self_inode_operations = { .readlink = proc_self_readlink, - .follow_link = proc_self_follow_link, + .get_link = proc_self_get_link, .put_link = kfree_put_link, }; diff --git a/fs/proc/thread_self.c b/fs/proc/thread_self.c index 947b0f4fd0a1..50eef6f3e671 100644 --- a/fs/proc/thread_self.c +++ b/fs/proc/thread_self.c @@ -19,13 +19,16 @@ static int proc_thread_self_readlink(struct dentry *dentry, char __user *buffer, return readlink_copy(buffer, buflen, tmp); } -static const char *proc_thread_self_follow_link(struct dentry *dentry, void **cookie) +static const char *proc_thread_self_get_link(struct dentry *dentry, + struct inode *inode, void **cookie) { - struct pid_namespace *ns = dentry->d_sb->s_fs_info; + struct pid_namespace *ns = inode->i_sb->s_fs_info; pid_t tgid = task_tgid_nr_ns(current, ns); pid_t pid = task_pid_nr_ns(current, ns); char *name; + if (!dentry) + return ERR_PTR(-ECHILD); if (!pid) return ERR_PTR(-ENOENT); name = kmalloc(PROC_NUMBUF + 6 + PROC_NUMBUF, GFP_KERNEL); @@ -37,7 +40,7 @@ static const char *proc_thread_self_follow_link(struct dentry *dentry, void **co static const struct inode_operations proc_thread_self_inode_operations = { .readlink = proc_thread_self_readlink, - .follow_link = proc_thread_self_follow_link, + .get_link = proc_thread_self_get_link, .put_link = kfree_put_link, }; diff --git a/fs/reiserfs/namei.c b/fs/reiserfs/namei.c index 4fc2326fac03..ecbf11e961ab 100644 --- a/fs/reiserfs/namei.c +++ b/fs/reiserfs/namei.c @@ -1665,7 +1665,7 @@ const struct inode_operations reiserfs_dir_inode_operations = { */ const struct inode_operations reiserfs_symlink_inode_operations = { .readlink = generic_readlink, - .follow_link = page_follow_link_light, + .get_link = page_get_link, .put_link = page_put_link, .setattr = reiserfs_setattr, .setxattr = reiserfs_setxattr, diff --git a/fs/squashfs/symlink.c b/fs/squashfs/symlink.c index 12806dffb345..7c635a5da783 100644 --- a/fs/squashfs/symlink.c +++ b/fs/squashfs/symlink.c @@ -119,7 +119,7 @@ const struct address_space_operations squashfs_symlink_aops = { const struct inode_operations squashfs_symlink_inode_ops = { .readlink = generic_readlink, - .follow_link = page_follow_link_light, + .get_link = page_get_link, .put_link = page_put_link, .getxattr = generic_getxattr, .listxattr = squashfs_listxattr diff --git a/fs/sysv/inode.c b/fs/sysv/inode.c index ef8bcdb80aca..80a40bcb721c 100644 --- a/fs/sysv/inode.c +++ b/fs/sysv/inode.c @@ -146,7 +146,7 @@ static inline void write3byte(struct sysv_sb_info *sbi, static const struct inode_operations sysv_symlink_inode_operations = { .readlink = generic_readlink, - .follow_link = page_follow_link_light, + .get_link = page_get_link, .put_link = page_put_link, .getattr = sysv_getattr, }; diff --git a/fs/ubifs/file.c b/fs/ubifs/file.c index 0edc12856147..eff62801acbf 100644 --- a/fs/ubifs/file.c +++ b/fs/ubifs/file.c @@ -1608,7 +1608,7 @@ const struct inode_operations ubifs_file_inode_operations = { const struct inode_operations ubifs_symlink_inode_operations = { .readlink = generic_readlink, - .follow_link = simple_follow_link, + .get_link = simple_get_link, .setattr = ubifs_setattr, .getattr = ubifs_getattr, .setxattr = ubifs_setxattr, diff --git a/fs/xfs/xfs_iops.c b/fs/xfs/xfs_iops.c index 245268a0cdf0..f638fd58b5b3 100644 --- a/fs/xfs/xfs_iops.c +++ b/fs/xfs/xfs_iops.c @@ -414,13 +414,17 @@ xfs_vn_rename( * uio is kmalloced for this reason... */ STATIC const char * -xfs_vn_follow_link( +xfs_vn_get_link( struct dentry *dentry, + struct inode *inode, void **cookie) { char *link; int error = -ENOMEM; + if (!dentry) + return ERR_PTR(-ECHILD); + link = kmalloc(MAXPATHLEN+1, GFP_KERNEL); if (!link) goto out_err; @@ -1172,7 +1176,7 @@ static const struct inode_operations xfs_dir_ci_inode_operations = { static const struct inode_operations xfs_symlink_inode_operations = { .readlink = generic_readlink, - .follow_link = xfs_vn_follow_link, + .get_link = xfs_vn_get_link, .put_link = kfree_put_link, .getattr = xfs_vn_getattr, .setattr = xfs_vn_setattr, diff --git a/include/linux/fs.h b/include/linux/fs.h index dfeda44b9ba4..d2fdf09a4407 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1633,7 +1633,7 @@ struct file_operations { struct inode_operations { struct dentry * (*lookup) (struct inode *,struct dentry *, unsigned int); - const char * (*follow_link) (struct dentry *, void **); + const char * (*get_link) (struct dentry *, struct inode *, void **); int (*permission) (struct inode *, int); struct posix_acl * (*get_acl)(struct inode *, int); @@ -2736,7 +2736,7 @@ extern const struct file_operations generic_ro_fops; extern int readlink_copy(char __user *, int, const char *); extern int page_readlink(struct dentry *, char __user *, int); -extern const char *page_follow_link_light(struct dentry *, void **); +extern const char *page_get_link(struct dentry *, struct inode *, void **); extern void page_put_link(struct inode *, void *); extern int __page_symlink(struct inode *inode, const char *symname, int len, int nofs); @@ -2754,7 +2754,7 @@ void __inode_sub_bytes(struct inode *inode, loff_t bytes); void inode_sub_bytes(struct inode *inode, loff_t bytes); loff_t inode_get_bytes(struct inode *inode); void inode_set_bytes(struct inode *inode, loff_t bytes); -const char *simple_follow_link(struct dentry *, void **); +const char *simple_get_link(struct dentry *, struct inode *, void **); extern const struct inode_operations simple_symlink_inode_operations; extern int iterate_dir(struct file *, struct dir_context *); diff --git a/mm/shmem.c b/mm/shmem.c index 64bf5acb49fe..684dbc32e233 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -2496,10 +2496,14 @@ static int shmem_symlink(struct inode *dir, struct dentry *dentry, const char *s return 0; } -static const char *shmem_follow_link(struct dentry *dentry, void **cookie) +static const char *shmem_get_link(struct dentry *dentry, + struct inode *inode, void **cookie) { struct page *page = NULL; - int error = shmem_getpage(d_inode(dentry), 0, &page, SGP_READ, NULL); + int error; + if (!dentry) + return ERR_PTR(-ECHILD); + error = shmem_getpage(inode, 0, &page, SGP_READ, NULL); if (error) return ERR_PTR(error); unlock_page(page); @@ -2656,7 +2660,7 @@ static ssize_t shmem_listxattr(struct dentry *dentry, char *buffer, size_t size) static const struct inode_operations shmem_short_symlink_operations = { .readlink = generic_readlink, - .follow_link = simple_follow_link, + .get_link = simple_get_link, #ifdef CONFIG_TMPFS_XATTR .setxattr = shmem_setxattr, .getxattr = shmem_getxattr, @@ -2667,7 +2671,7 @@ static const struct inode_operations shmem_short_symlink_operations = { static const struct inode_operations shmem_symlink_inode_operations = { .readlink = generic_readlink, - .follow_link = shmem_follow_link, + .get_link = shmem_get_link, .put_link = shmem_put_link, #ifdef CONFIG_TMPFS_XATTR .setxattr = shmem_setxattr, -- cgit v1.2.3 From 7acccdbc4d0bf78a613008e92a3e6c32e37ef26f Mon Sep 17 00:00:00 2001 From: Masanari Iida Date: Thu, 10 Dec 2015 00:59:29 +0900 Subject: Doc: treewide: Fix grammar "a" to "an" This patch fix some grammar mistake. Signed-off-by: Masanari Iida Signed-off-by: Jonathan Corbet --- Documentation/filesystems/sharedsubtree.txt | 2 +- Documentation/vm/slub.txt | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) (limited to 'Documentation/filesystems') diff --git a/Documentation/filesystems/sharedsubtree.txt b/Documentation/filesystems/sharedsubtree.txt index 32a173dd3158..e3f4c778eb98 100644 --- a/Documentation/filesystems/sharedsubtree.txt +++ b/Documentation/filesystems/sharedsubtree.txt @@ -664,7 +664,7 @@ replicas continue to be exactly same. if one rbind mounts a tree within the same subtree 'n' times the number of mounts created is an exponential function of 'n'. Having unbindable mount can help prune the unneeded bind - mounts. Here is a example. + mounts. Here is an example. step 1: let's say the root tree has just two directories with diff --git a/Documentation/vm/slub.txt b/Documentation/vm/slub.txt index 699d8ea5c230..f0d340959319 100644 --- a/Documentation/vm/slub.txt +++ b/Documentation/vm/slub.txt @@ -8,7 +8,7 @@ SLUB can enable debugging only for selected slabs in order to avoid an impact on overall system performance which may make a bug more difficult to find. -In order to switch debugging on one can add a option "slub_debug" +In order to switch debugging on one can add an option "slub_debug" to the kernel command line. That will enable full debugging for all slabs. -- cgit v1.2.3 From 343f40f0a70eb7cee9cc8d6fcfbb3917252a5245 Mon Sep 17 00:00:00 2001 From: Chao Yu Date: Wed, 16 Dec 2015 13:12:16 +0800 Subject: f2fs: introduce new option for controlling data flush Add a new option 'data_flush' to enable data flush functionality. Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim --- Documentation/filesystems/f2fs.txt | 2 ++ fs/f2fs/f2fs.h | 1 + fs/f2fs/super.c | 7 +++++++ 3 files changed, 10 insertions(+) (limited to 'Documentation/filesystems') diff --git a/Documentation/filesystems/f2fs.txt b/Documentation/filesystems/f2fs.txt index ad10494aa224..e1c9f0849da6 100644 --- a/Documentation/filesystems/f2fs.txt +++ b/Documentation/filesystems/f2fs.txt @@ -149,6 +149,8 @@ noextent_cache Disable an extent cache based on rb-tree explicitly, see the above extent_cache mount option. noinline_data Disable the inline data feature, inline data feature is enabled by default. +data_flush Enable data flushing before checkpoint in order to + persist data of regular and symlink. ================================================================================ DEBUGFS ENTRIES diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h index 03a2b86a28ba..b1fb8f73fe42 100644 --- a/fs/f2fs/f2fs.h +++ b/fs/f2fs/f2fs.h @@ -54,6 +54,7 @@ #define F2FS_MOUNT_FASTBOOT 0x00001000 #define F2FS_MOUNT_EXTENT_CACHE 0x00002000 #define F2FS_MOUNT_FORCE_FG_GC 0x00004000 +#define F2FS_MOUNT_DATA_FLUSH 0x00008000 #define clear_opt(sbi, option) (sbi->mount_opt.opt &= ~F2FS_MOUNT_##option) #define set_opt(sbi, option) (sbi->mount_opt.opt |= F2FS_MOUNT_##option) diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c index 5b596d6a8d24..c3070c149c0e 100644 --- a/fs/f2fs/super.c +++ b/fs/f2fs/super.c @@ -67,6 +67,7 @@ enum { Opt_extent_cache, Opt_noextent_cache, Opt_noinline_data, + Opt_data_flush, Opt_err, }; @@ -91,6 +92,7 @@ static match_table_t f2fs_tokens = { {Opt_extent_cache, "extent_cache"}, {Opt_noextent_cache, "noextent_cache"}, {Opt_noinline_data, "noinline_data"}, + {Opt_data_flush, "data_flush"}, {Opt_err, NULL}, }; @@ -406,6 +408,9 @@ static int parse_options(struct super_block *sb, char *options) case Opt_noinline_data: clear_opt(sbi, INLINE_DATA); break; + case Opt_data_flush: + set_opt(sbi, DATA_FLUSH); + break; default: f2fs_msg(sb, KERN_ERR, "Unrecognized mount option \"%s\" or missing value", @@ -687,6 +692,8 @@ static int f2fs_show_options(struct seq_file *seq, struct dentry *root) seq_puts(seq, ",extent_cache"); else seq_puts(seq, ",noextent_cache"); + if (test_opt(sbi, DATA_FLUSH)) + seq_puts(seq, ",data_flush"); seq_printf(seq, ",active_logs=%u", sbi->active_logs); return 0; -- cgit v1.2.3 From fceef393a538134f03b778c5d2519e670269342f Mon Sep 17 00:00:00 2001 From: Al Viro Date: Tue, 29 Dec 2015 15:58:39 -0500 Subject: switch ->get_link() to delayed_call, kill ->put_link() Signed-off-by: Al Viro --- Documentation/filesystems/Locking | 2 - Documentation/filesystems/porting | 6 +++ Documentation/filesystems/vfs.txt | 21 +++++---- drivers/staging/lustre/lustre/llite/symlink.c | 18 ++++---- fs/9p/vfs_inode.c | 9 ++-- fs/9p/vfs_inode_dotl.c | 9 ++-- fs/affs/symlink.c | 1 - fs/autofs4/symlink.c | 3 +- fs/btrfs/inode.c | 1 - fs/cifs/cifsfs.c | 1 - fs/cifs/cifsfs.h | 3 +- fs/cifs/link.c | 6 ++- fs/coda/cnode.c | 1 - fs/configfs/symlink.c | 17 ++++---- fs/ecryptfs/inode.c | 7 +-- fs/ext2/symlink.c | 1 - fs/ext4/symlink.c | 8 ++-- fs/f2fs/namei.c | 16 ++++--- fs/fuse/dir.c | 6 +-- fs/gfs2/inode.c | 8 ++-- fs/hostfs/hostfs_kern.c | 16 +++---- fs/jfs/symlink.c | 1 - fs/kernfs/symlink.c | 19 ++++---- fs/libfs.c | 9 ++-- fs/minix/inode.c | 1 - fs/namei.c | 63 +++++++++++---------------- fs/ncpfs/inode.c | 1 - fs/nfs/symlink.c | 6 +-- fs/nilfs2/namei.c | 1 - fs/ocfs2/symlink.c | 1 - fs/overlayfs/inode.c | 45 ++----------------- fs/proc/base.c | 8 ++-- fs/proc/inode.c | 16 +++---- fs/proc/namespaces.c | 3 +- fs/proc/self.c | 7 +-- fs/proc/thread_self.c | 7 +-- fs/reiserfs/namei.c | 1 - fs/squashfs/symlink.c | 1 - fs/sysv/inode.c | 1 - fs/xfs/xfs_iops.c | 6 +-- include/linux/delayed_call.h | 34 +++++++++++++++ include/linux/fs.h | 14 +++--- mm/shmem.c | 19 ++++---- 43 files changed, 206 insertions(+), 218 deletions(-) create mode 100644 include/linux/delayed_call.h (limited to 'Documentation/filesystems') diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking index 4fba54b9fcec..619af9bfdcb3 100644 --- a/Documentation/filesystems/Locking +++ b/Documentation/filesystems/Locking @@ -51,7 +51,6 @@ prototypes: struct inode *, struct dentry *, unsigned int); int (*readlink) (struct dentry *, char __user *,int); const char *(*get_link) (struct dentry *, struct inode *, void **); - void (*put_link) (struct inode *, void *); void (*truncate) (struct inode *); int (*permission) (struct inode *, int, unsigned int); int (*get_acl)(struct inode *, int); @@ -84,7 +83,6 @@ rename: yes (all) (see below) rename2: yes (all) (see below) readlink: no get_link: no -put_link: no setattr: yes permission: no (may not block if called in rcu-walk mode) get_acl: no diff --git a/Documentation/filesystems/porting b/Documentation/filesystems/porting index cf92a8c55594..0f88e6020487 100644 --- a/Documentation/filesystems/porting +++ b/Documentation/filesystems/porting @@ -515,3 +515,9 @@ in your dentry operations instead. * ->get_link() gets inode as a separate argument * ->get_link() may be called in RCU mode - in that case NULL dentry is passed +-- +[mandatory] + ->get_link() gets struct delayed_call *done now, and should do + set_delayed_call() where it used to set *cookie. + ->put_link() is gone - just give the destructor to set_delayed_call() + in ->get_link(). diff --git a/Documentation/filesystems/vfs.txt b/Documentation/filesystems/vfs.txt index 8c6f07ad373a..b02a7d598258 100644 --- a/Documentation/filesystems/vfs.txt +++ b/Documentation/filesystems/vfs.txt @@ -350,8 +350,8 @@ struct inode_operations { int (*rename2) (struct inode *, struct dentry *, struct inode *, struct dentry *, unsigned int); int (*readlink) (struct dentry *, char __user *,int); - const char *(*follow_link) (struct dentry *, void **); - void (*put_link) (struct inode *, void *); + const char *(*get_link) (struct dentry *, struct inode *, + struct delayed_call *); int (*permission) (struct inode *, int); int (*get_acl)(struct inode *, int); int (*setattr) (struct dentry *, struct iattr *); @@ -434,20 +434,19 @@ otherwise noted. readlink: called by the readlink(2) system call. Only required if you want to support reading symbolic links - follow_link: called by the VFS to follow a symbolic link to the + get_link: called by the VFS to follow a symbolic link to the inode it points to. Only required if you want to support symbolic links. This method returns the symlink body to traverse (and possibly resets the current position with nd_jump_link()). If the body won't go away until the inode is gone, nothing else is needed; if it needs to be otherwise - pinned, the data needed to release whatever we'd grabbed - is to be stored in void * variable passed by address to - follow_link() instance. - - put_link: called by the VFS to release resources allocated by - follow_link(). The cookie stored by follow_link() is passed - to this method as the last parameter; only called when - cookie isn't NULL. + pinned, arrange for its release by having get_link(..., ..., done) + do set_delayed_call(done, destructor, argument). + In that case destructor(argument) will be called once VFS is + done with the body you've returned. + May be called in RCU mode; that is indicated by NULL dentry + argument. If request can't be handled without leaving RCU mode, + have it return ERR_PTR(-ECHILD). permission: called by the VFS to check for access rights on a POSIX-like filesystem. diff --git a/drivers/staging/lustre/lustre/llite/symlink.c b/drivers/staging/lustre/lustre/llite/symlink.c index 153fdf908328..e489a3271f06 100644 --- a/drivers/staging/lustre/lustre/llite/symlink.c +++ b/drivers/staging/lustre/lustre/llite/symlink.c @@ -118,8 +118,14 @@ failed: return rc; } +static void ll_put_link(void *p) +{ + ptlrpc_req_finished(p); +} + static const char *ll_get_link(struct dentry *dentry, - struct inode *inode, void **cookie) + struct inode *inode, + struct delayed_call *done) { struct ptlrpc_request *request = NULL; int rc; @@ -137,22 +143,16 @@ static const char *ll_get_link(struct dentry *dentry, } /* symname may contain a pointer to the request message buffer, - * we delay request releasing until ll_put_link then. + * we delay request releasing then. */ - *cookie = request; + set_delayed_call(done, ll_put_link, request); return symname; } -static void ll_put_link(struct inode *unused, void *cookie) -{ - ptlrpc_req_finished(cookie); -} - struct inode_operations ll_fast_symlink_inode_operations = { .readlink = generic_readlink, .setattr = ll_setattr, .get_link = ll_get_link, - .put_link = ll_put_link, .getattr = ll_getattr, .permission = ll_inode_permission, .setxattr = ll_setxattr, diff --git a/fs/9p/vfs_inode.c b/fs/9p/vfs_inode.c index 8ba5a897fc0a..f928f8702f4c 100644 --- a/fs/9p/vfs_inode.c +++ b/fs/9p/vfs_inode.c @@ -1226,11 +1226,12 @@ ino_t v9fs_qid2ino(struct p9_qid *qid) * v9fs_vfs_get_link - follow a symlink path * @dentry: dentry for symlink * @inode: inode for symlink - * @cookie: place to pass the data to put_link() + * @done: delayed call for when we are done with the return value */ static const char *v9fs_vfs_get_link(struct dentry *dentry, - struct inode *inode, void **cookie) + struct inode *inode, + struct delayed_call *done) { struct v9fs_session_info *v9ses; struct p9_fid *fid; @@ -1266,7 +1267,8 @@ static const char *v9fs_vfs_get_link(struct dentry *dentry, p9stat_free(st); kfree(st); - return *cookie = res; + set_delayed_call(done, kfree_link, res); + return res; } /** @@ -1460,7 +1462,6 @@ static const struct inode_operations v9fs_file_inode_operations = { static const struct inode_operations v9fs_symlink_inode_operations = { .readlink = generic_readlink, .get_link = v9fs_vfs_get_link, - .put_link = kfree_put_link, .getattr = v9fs_vfs_getattr, .setattr = v9fs_vfs_setattr, }; diff --git a/fs/9p/vfs_inode_dotl.c b/fs/9p/vfs_inode_dotl.c index 0cc105d804dd..a34702c998f5 100644 --- a/fs/9p/vfs_inode_dotl.c +++ b/fs/9p/vfs_inode_dotl.c @@ -902,12 +902,13 @@ error: * v9fs_vfs_get_link_dotl - follow a symlink path * @dentry: dentry for symlink * @inode: inode for symlink - * @cookie: place to pass the data to put_link() + * @done: destructor for return value */ static const char * v9fs_vfs_get_link_dotl(struct dentry *dentry, - struct inode *inode, void **cookie) + struct inode *inode, + struct delayed_call *done) { struct p9_fid *fid; char *target; @@ -924,7 +925,8 @@ v9fs_vfs_get_link_dotl(struct dentry *dentry, retval = p9_client_readlink(fid, &target); if (retval) return ERR_PTR(retval); - return *cookie = target; + set_delayed_call(done, kfree_link, target); + return target; } int v9fs_refresh_inode_dotl(struct p9_fid *fid, struct inode *inode) @@ -991,7 +993,6 @@ const struct inode_operations v9fs_file_inode_operations_dotl = { const struct inode_operations v9fs_symlink_inode_operations_dotl = { .readlink = generic_readlink, .get_link = v9fs_vfs_get_link_dotl, - .put_link = kfree_put_link, .getattr = v9fs_vfs_getattr_dotl, .setattr = v9fs_vfs_setattr_dotl, .setxattr = generic_setxattr, diff --git a/fs/affs/symlink.c b/fs/affs/symlink.c index 39d1194445e1..69b03dbb792f 100644 --- a/fs/affs/symlink.c +++ b/fs/affs/symlink.c @@ -72,6 +72,5 @@ const struct address_space_operations affs_symlink_aops = { const struct inode_operations affs_symlink_inode_operations = { .readlink = generic_readlink, .get_link = page_get_link, - .put_link = page_put_link, .setattr = affs_notify_change, }; diff --git a/fs/autofs4/symlink.c b/fs/autofs4/symlink.c index 39e6f0bdf8e3..84e037d1d129 100644 --- a/fs/autofs4/symlink.c +++ b/fs/autofs4/symlink.c @@ -13,7 +13,8 @@ #include "autofs_i.h" static const char *autofs4_get_link(struct dentry *dentry, - struct inode *inode, void **cookie) + struct inode *inode, + struct delayed_call *done) { struct autofs_sb_info *sbi; struct autofs_info *ino; diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 3d4aa69f1e0c..1a41a65fd2ff 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -10097,7 +10097,6 @@ static const struct inode_operations btrfs_special_inode_operations = { static const struct inode_operations btrfs_symlink_inode_operations = { .readlink = generic_readlink, .get_link = page_get_link, - .put_link = page_put_link, .getattr = btrfs_getattr, .setattr = btrfs_setattr, .permission = btrfs_permission, diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c index 4593f41678ef..90e4e2b398b6 100644 --- a/fs/cifs/cifsfs.c +++ b/fs/cifs/cifsfs.c @@ -901,7 +901,6 @@ const struct inode_operations cifs_file_inode_ops = { const struct inode_operations cifs_symlink_inode_ops = { .readlink = generic_readlink, .get_link = cifs_get_link, - .put_link = kfree_put_link, .permission = cifs_permission, /* BB add the following two eventually */ /* revalidate: cifs_revalidate, diff --git a/fs/cifs/cifsfs.h b/fs/cifs/cifsfs.h index 6886328cf3c4..26a1187d4323 100644 --- a/fs/cifs/cifsfs.h +++ b/fs/cifs/cifsfs.h @@ -120,7 +120,8 @@ extern struct vfsmount *cifs_dfs_d_automount(struct path *path); #endif /* Functions related to symlinks */ -extern const char *cifs_get_link(struct dentry *, struct inode *, void **); +extern const char *cifs_get_link(struct dentry *, struct inode *, + struct delayed_call *); extern int cifs_symlink(struct inode *inode, struct dentry *direntry, const char *symname); extern int cifs_removexattr(struct dentry *, const char *); diff --git a/fs/cifs/link.c b/fs/cifs/link.c index 6f2439b508b5..062c2375549a 100644 --- a/fs/cifs/link.c +++ b/fs/cifs/link.c @@ -627,7 +627,8 @@ cifs_hl_exit: } const char * -cifs_get_link(struct dentry *direntry, struct inode *inode, void **cookie) +cifs_get_link(struct dentry *direntry, struct inode *inode, + struct delayed_call *done) { int rc = -ENOMEM; unsigned int xid; @@ -680,7 +681,8 @@ cifs_get_link(struct dentry *direntry, struct inode *inode, void **cookie) kfree(target_path); return ERR_PTR(rc); } - return *cookie = target_path; + set_delayed_call(done, kfree_link, target_path); + return target_path; } int diff --git a/fs/coda/cnode.c b/fs/coda/cnode.c index f18139c7690a..1bfb7ba4e85e 100644 --- a/fs/coda/cnode.c +++ b/fs/coda/cnode.c @@ -19,7 +19,6 @@ static inline int coda_fideq(struct CodaFid *fid1, struct CodaFid *fid2) static const struct inode_operations coda_symlink_inode_operations = { .readlink = generic_readlink, .get_link = page_get_link, - .put_link = page_put_link, .setattr = coda_setattr, }; diff --git a/fs/configfs/symlink.c b/fs/configfs/symlink.c index e9de962e518d..db6d69289608 100644 --- a/fs/configfs/symlink.c +++ b/fs/configfs/symlink.c @@ -280,31 +280,32 @@ static int configfs_getlink(struct dentry *dentry, char * path) } static const char *configfs_get_link(struct dentry *dentry, - struct inode *inode, void **cookie) + struct inode *inode, + struct delayed_call *done) { - char *page; + char *body; int error; if (!dentry) return ERR_PTR(-ECHILD); - page = kzalloc(PAGE_SIZE, GFP_KERNEL); - if (!page) + body = kzalloc(PAGE_SIZE, GFP_KERNEL); + if (!body) return ERR_PTR(-ENOMEM); - error = configfs_getlink(dentry, page); + error = configfs_getlink(dentry, body); if (!error) { - return *cookie = page; + set_delayed_call(done, kfree_link, body); + return body; } - kfree(page); + kfree(body); return ERR_PTR(error); } const struct inode_operations configfs_symlink_inode_operations = { .get_link = configfs_get_link, .readlink = generic_readlink, - .put_link = kfree_put_link, .setattr = configfs_setattr, }; diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c index 5a05559cb23d..a4dddc61594c 100644 --- a/fs/ecryptfs/inode.c +++ b/fs/ecryptfs/inode.c @@ -675,7 +675,8 @@ out: } static const char *ecryptfs_get_link(struct dentry *dentry, - struct inode *inode, void **cookie) + struct inode *inode, + struct delayed_call *done) { size_t len; char *buf; @@ -689,7 +690,8 @@ static const char *ecryptfs_get_link(struct dentry *dentry, fsstack_copy_attr_atime(d_inode(dentry), d_inode(ecryptfs_dentry_to_lower(dentry))); buf[len] = '\0'; - return *cookie = buf; + set_delayed_call(done, kfree_link, buf); + return buf; } /** @@ -1102,7 +1104,6 @@ out: const struct inode_operations ecryptfs_symlink_iops = { .readlink = generic_readlink, .get_link = ecryptfs_get_link, - .put_link = kfree_put_link, .permission = ecryptfs_permission, .setattr = ecryptfs_setattr, .getattr = ecryptfs_getattr_link, diff --git a/fs/ext2/symlink.c b/fs/ext2/symlink.c index 46905119a27c..3495d8ae4b33 100644 --- a/fs/ext2/symlink.c +++ b/fs/ext2/symlink.c @@ -23,7 +23,6 @@ const struct inode_operations ext2_symlink_inode_operations = { .readlink = generic_readlink, .get_link = page_get_link, - .put_link = page_put_link, .setattr = ext2_setattr, #ifdef CONFIG_EXT2_FS_XATTR .setxattr = generic_setxattr, diff --git a/fs/ext4/symlink.c b/fs/ext4/symlink.c index 3b4bfe2ebd75..2281ac27b213 100644 --- a/fs/ext4/symlink.c +++ b/fs/ext4/symlink.c @@ -24,7 +24,8 @@ #ifdef CONFIG_EXT4_FS_ENCRYPTION static const char *ext4_encrypted_get_link(struct dentry *dentry, - struct inode *inode, void **cookie) + struct inode *inode, + struct delayed_call *done) { struct page *cpage = NULL; char *caddr, *paddr = NULL; @@ -80,7 +81,8 @@ static const char *ext4_encrypted_get_link(struct dentry *dentry, paddr[res] = '\0'; if (cpage) page_cache_release(cpage); - return *cookie = paddr; + set_delayed_call(done, kfree_link, paddr); + return paddr; errout: if (cpage) page_cache_release(cpage); @@ -91,7 +93,6 @@ errout: const struct inode_operations ext4_encrypted_symlink_inode_operations = { .readlink = generic_readlink, .get_link = ext4_encrypted_get_link, - .put_link = kfree_put_link, .setattr = ext4_setattr, .setxattr = generic_setxattr, .getxattr = generic_getxattr, @@ -103,7 +104,6 @@ const struct inode_operations ext4_encrypted_symlink_inode_operations = { const struct inode_operations ext4_symlink_inode_operations = { .readlink = generic_readlink, .get_link = page_get_link, - .put_link = page_put_link, .setattr = ext4_setattr, .setxattr = generic_setxattr, .getxattr = generic_getxattr, diff --git a/fs/f2fs/namei.c b/fs/f2fs/namei.c index 2a8d84b727ce..e7587fce1b80 100644 --- a/fs/f2fs/namei.c +++ b/fs/f2fs/namei.c @@ -316,12 +316,14 @@ fail: } static const char *f2fs_get_link(struct dentry *dentry, - struct inode *inode, void **cookie) + struct inode *inode, + struct delayed_call *done) { - const char *link = page_get_link(dentry, inode, cookie); + const char *link = page_get_link(dentry, inode, done); if (!IS_ERR(link) && !*link) { /* this is broken symlink case */ - page_put_link(NULL, *cookie); + do_delayed_call(done); + clear_delayed_call(done); link = ERR_PTR(-ENOENT); } return link; @@ -926,7 +928,8 @@ static int f2fs_rename2(struct inode *old_dir, struct dentry *old_dentry, #ifdef CONFIG_F2FS_FS_ENCRYPTION static const char *f2fs_encrypted_get_link(struct dentry *dentry, - struct inode *inode, void **cookie) + struct inode *inode, + struct delayed_call *done) { struct page *cpage = NULL; char *caddr, *paddr = NULL; @@ -988,7 +991,8 @@ static const char *f2fs_encrypted_get_link(struct dentry *dentry, paddr[res] = '\0'; page_cache_release(cpage); - return *cookie = paddr; + set_delayed_call(done, kfree_link, paddr); + return paddr; errout: kfree(cstr.name); f2fs_fname_crypto_free_buffer(&pstr); @@ -999,7 +1003,6 @@ errout: const struct inode_operations f2fs_encrypted_symlink_inode_operations = { .readlink = generic_readlink, .get_link = f2fs_encrypted_get_link, - .put_link = kfree_put_link, .getattr = f2fs_getattr, .setattr = f2fs_setattr, .setxattr = generic_setxattr, @@ -1035,7 +1038,6 @@ const struct inode_operations f2fs_dir_inode_operations = { const struct inode_operations f2fs_symlink_inode_operations = { .readlink = generic_readlink, .get_link = f2fs_get_link, - .put_link = page_put_link, .getattr = f2fs_getattr, .setattr = f2fs_setattr, #ifdef CONFIG_F2FS_FS_XATTR diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c index def0a4d082bc..712601f299b8 100644 --- a/fs/fuse/dir.c +++ b/fs/fuse/dir.c @@ -1366,7 +1366,8 @@ static int fuse_readdir(struct file *file, struct dir_context *ctx) } static const char *fuse_get_link(struct dentry *dentry, - struct inode *inode, void **cookie) + struct inode *inode, + struct delayed_call *done) { struct fuse_conn *fc = get_fuse_conn(inode); FUSE_ARGS(args); @@ -1392,7 +1393,7 @@ static const char *fuse_get_link(struct dentry *dentry, link = ERR_PTR(ret); } else { link[ret] = '\0'; - *cookie = link; + set_delayed_call(done, kfree_link, link); } fuse_invalidate_atime(inode); return link; @@ -1913,7 +1914,6 @@ static const struct inode_operations fuse_common_inode_operations = { static const struct inode_operations fuse_symlink_inode_operations = { .setattr = fuse_setattr, .get_link = fuse_get_link, - .put_link = kfree_put_link, .readlink = generic_readlink, .getattr = fuse_getattr, .setxattr = fuse_setxattr, diff --git a/fs/gfs2/inode.c b/fs/gfs2/inode.c index 1095056046cc..1bae189f3245 100644 --- a/fs/gfs2/inode.c +++ b/fs/gfs2/inode.c @@ -1715,7 +1715,7 @@ static int gfs2_rename2(struct inode *odir, struct dentry *odentry, * gfs2_get_link - Follow a symbolic link * @dentry: The dentry of the link * @inode: The inode of the link - * @cookie: place to store the information for ->put_link() + * @done: destructor for return value * * This can handle symlinks of any size. * @@ -1723,7 +1723,8 @@ static int gfs2_rename2(struct inode *odir, struct dentry *odentry, */ static const char *gfs2_get_link(struct dentry *dentry, - struct inode *inode, void **cookie) + struct inode *inode, + struct delayed_call *done) { struct gfs2_inode *ip = GFS2_I(inode); struct gfs2_holder i_gh; @@ -1764,7 +1765,7 @@ static const char *gfs2_get_link(struct dentry *dentry, out: gfs2_glock_dq_uninit(&i_gh); if (!IS_ERR(buf)) - *cookie = buf; + set_delayed_call(done, kfree_link, buf); return buf; } @@ -2138,7 +2139,6 @@ const struct inode_operations gfs2_dir_iops = { const struct inode_operations gfs2_symlink_iops = { .readlink = generic_readlink, .get_link = gfs2_get_link, - .put_link = kfree_put_link, .permission = gfs2_permission, .setattr = gfs2_setattr, .getattr = gfs2_getattr, diff --git a/fs/hostfs/hostfs_kern.c b/fs/hostfs/hostfs_kern.c index 6ce5309ecb7b..7db524cc85b6 100644 --- a/fs/hostfs/hostfs_kern.c +++ b/fs/hostfs/hostfs_kern.c @@ -893,12 +893,13 @@ static const struct inode_operations hostfs_dir_iops = { }; static const char *hostfs_get_link(struct dentry *dentry, - struct inode *inode, void **cookie) + struct inode *inode, + struct delayed_call *done) { char *link; if (!dentry) return ERR_PTR(-ECHILD); - link = __getname(); + link = kmalloc(PATH_MAX, GFP_KERNEL); if (link) { char *path = dentry_name(dentry); int err = -ENOMEM; @@ -909,25 +910,20 @@ static const char *hostfs_get_link(struct dentry *dentry, __putname(path); } if (err < 0) { - __putname(link); + kfree(link); return ERR_PTR(err); } } else { return ERR_PTR(-ENOMEM); } - return *cookie = link; -} - -static void hostfs_put_link(struct inode *unused, void *cookie) -{ - __putname(cookie); + set_delayed_call(done, kfree_link, link); + return link; } static const struct inode_operations hostfs_link_iops = { .readlink = generic_readlink, .get_link = hostfs_get_link, - .put_link = hostfs_put_link, }; static int hostfs_fill_sb_common(struct super_block *sb, void *d, int silent) diff --git a/fs/jfs/symlink.c b/fs/jfs/symlink.c index 02113282772e..f8db4fde0b0b 100644 --- a/fs/jfs/symlink.c +++ b/fs/jfs/symlink.c @@ -34,7 +34,6 @@ const struct inode_operations jfs_fast_symlink_inode_operations = { const struct inode_operations jfs_symlink_inode_operations = { .readlink = generic_readlink, .get_link = page_get_link, - .put_link = page_put_link, .setattr = jfs_setattr, .setxattr = jfs_setxattr, .getxattr = jfs_getxattr, diff --git a/fs/kernfs/symlink.c b/fs/kernfs/symlink.c index f9efdaeda7b0..117b8b3416f9 100644 --- a/fs/kernfs/symlink.c +++ b/fs/kernfs/symlink.c @@ -113,22 +113,24 @@ static int kernfs_getlink(struct dentry *dentry, char *path) } static const char *kernfs_iop_get_link(struct dentry *dentry, - struct inode *inode, void **cookie) + struct inode *inode, + struct delayed_call *done) { - int error = -ENOMEM; - char *page; + char *body; + int error; if (!dentry) return ERR_PTR(-ECHILD); - page = kzalloc(PAGE_SIZE, GFP_KERNEL); - if (!page) + body = kzalloc(PAGE_SIZE, GFP_KERNEL); + if (!body) return ERR_PTR(-ENOMEM); - error = kernfs_getlink(dentry, page); + error = kernfs_getlink(dentry, body); if (unlikely(error < 0)) { - kfree(page); + kfree(body); return ERR_PTR(error); } - return *cookie = page; + set_delayed_call(done, kfree_link, body); + return body; } const struct inode_operations kernfs_symlink_iops = { @@ -138,7 +140,6 @@ const struct inode_operations kernfs_symlink_iops = { .listxattr = kernfs_iop_listxattr, .readlink = generic_readlink, .get_link = kernfs_iop_get_link, - .put_link = kfree_put_link, .setattr = kernfs_iop_setattr, .getattr = kernfs_iop_getattr, .permission = kernfs_iop_permission, diff --git a/fs/libfs.c b/fs/libfs.c index fec7ab0632dc..01491299f348 100644 --- a/fs/libfs.c +++ b/fs/libfs.c @@ -1019,11 +1019,12 @@ int noop_fsync(struct file *file, loff_t start, loff_t end, int datasync) } EXPORT_SYMBOL(noop_fsync); -void kfree_put_link(struct inode *unused, void *cookie) +/* Because kfree isn't assignment-compatible with void(void*) ;-/ */ +void kfree_link(void *p) { - kfree(cookie); + kfree(p); } -EXPORT_SYMBOL(kfree_put_link); +EXPORT_SYMBOL(kfree_link); /* * nop .set_page_dirty method so that people can use .page_mkwrite on @@ -1087,7 +1088,7 @@ simple_nosetlease(struct file *filp, long arg, struct file_lock **flp, EXPORT_SYMBOL(simple_nosetlease); const char *simple_get_link(struct dentry *dentry, struct inode *inode, - void **cookie) + struct delayed_call *done) { return inode->i_link; } diff --git a/fs/minix/inode.c b/fs/minix/inode.c index 3cce709a8729..cb1789ca1ee6 100644 --- a/fs/minix/inode.c +++ b/fs/minix/inode.c @@ -436,7 +436,6 @@ static const struct address_space_operations minix_aops = { static const struct inode_operations minix_symlink_inode_operations = { .readlink = generic_readlink, .get_link = page_get_link, - .put_link = page_put_link, .getattr = minix_getattr, }; diff --git a/fs/namei.c b/fs/namei.c index 8f517888c3e1..3c909aebef70 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -505,13 +505,13 @@ struct nameidata { int total_link_count; struct saved { struct path link; - void *cookie; + struct delayed_call done; const char *name; - struct inode *inode; unsigned seq; } *stack, internal[EMBEDDED_LEVELS]; struct filename *name; struct nameidata *saved; + struct inode *link_inode; unsigned root_seq; int dfd; }; @@ -592,11 +592,8 @@ static void drop_links(struct nameidata *nd) int i = nd->depth; while (i--) { struct saved *last = nd->stack + i; - struct inode *inode = last->inode; - if (last->cookie && inode->i_op->put_link) { - inode->i_op->put_link(inode, last->cookie); - last->cookie = NULL; - } + do_delayed_call(&last->done); + clear_delayed_call(&last->done); } } @@ -858,9 +855,7 @@ void nd_jump_link(struct path *path) static inline void put_link(struct nameidata *nd) { struct saved *last = nd->stack + --nd->depth; - struct inode *inode = last->inode; - if (last->cookie && inode->i_op->put_link) - inode->i_op->put_link(inode, last->cookie); + do_delayed_call(&last->done); if (!(nd->flags & LOOKUP_RCU)) path_put(&last->link); } @@ -892,7 +887,7 @@ static inline int may_follow_link(struct nameidata *nd) return 0; /* Allowed if owner and follower match. */ - inode = nd->stack[0].inode; + inode = nd->link_inode; if (uid_eq(current_cred()->fsuid, inode->i_uid)) return 0; @@ -983,7 +978,7 @@ const char *get_link(struct nameidata *nd) { struct saved *last = nd->stack + nd->depth - 1; struct dentry *dentry = last->link.dentry; - struct inode *inode = last->inode; + struct inode *inode = nd->link_inode; int error; const char *res; @@ -1004,23 +999,21 @@ const char *get_link(struct nameidata *nd) nd->last_type = LAST_BIND; res = inode->i_link; if (!res) { + const char * (*get)(struct dentry *, struct inode *, + struct delayed_call *); + get = inode->i_op->get_link; if (nd->flags & LOOKUP_RCU) { - res = inode->i_op->get_link(NULL, inode, - &last->cookie); + res = get(NULL, inode, &last->done); if (res == ERR_PTR(-ECHILD)) { if (unlikely(unlazy_walk(nd, NULL, 0))) return ERR_PTR(-ECHILD); - res = inode->i_op->get_link(dentry, inode, - &last->cookie); + res = get(dentry, inode, &last->done); } } else { - res = inode->i_op->get_link(dentry, inode, - &last->cookie); + res = get(dentry, inode, &last->done); } - if (IS_ERR_OR_NULL(res)) { - last->cookie = NULL; + if (IS_ERR_OR_NULL(res)) return res; - } } if (*res == '/') { if (nd->flags & LOOKUP_RCU) { @@ -1699,8 +1692,8 @@ static int pick_link(struct nameidata *nd, struct path *link, last = nd->stack + nd->depth++; last->link = *link; - last->cookie = NULL; - last->inode = inode; + clear_delayed_call(&last->done); + nd->link_inode = inode; last->seq = seq; return 1; } @@ -4508,26 +4501,25 @@ EXPORT_SYMBOL(readlink_copy); */ int generic_readlink(struct dentry *dentry, char __user *buffer, int buflen) { - void *cookie; + DEFINE_DELAYED_CALL(done); struct inode *inode = d_inode(dentry); const char *link = inode->i_link; int res; if (!link) { - link = inode->i_op->get_link(dentry, inode, &cookie); + link = inode->i_op->get_link(dentry, inode, &done); if (IS_ERR(link)) return PTR_ERR(link); } res = readlink_copy(buffer, buflen, link); - if (inode->i_op->put_link) - inode->i_op->put_link(inode, cookie); + do_delayed_call(&done); return res; } EXPORT_SYMBOL(generic_readlink); /* get the link contents into pagecache */ const char *page_get_link(struct dentry *dentry, struct inode *inode, - void **cookie) + struct delayed_call *callback) { char *kaddr; struct page *page; @@ -4546,7 +4538,7 @@ const char *page_get_link(struct dentry *dentry, struct inode *inode, if (IS_ERR(page)) return (char*)page; } - *cookie = page; + set_delayed_call(callback, page_put_link, page); BUG_ON(mapping_gfp_mask(mapping) & __GFP_HIGHMEM); kaddr = page_address(page); nd_terminate_link(kaddr, inode->i_size, PAGE_SIZE - 1); @@ -4555,21 +4547,19 @@ const char *page_get_link(struct dentry *dentry, struct inode *inode, EXPORT_SYMBOL(page_get_link); -void page_put_link(struct inode *unused, void *cookie) +void page_put_link(void *arg) { - struct page *page = cookie; - page_cache_release(page); + put_page(arg); } EXPORT_SYMBOL(page_put_link); int page_readlink(struct dentry *dentry, char __user *buffer, int buflen) { - void *cookie = NULL; + DEFINE_DELAYED_CALL(done); int res = readlink_copy(buffer, buflen, page_get_link(dentry, d_inode(dentry), - &cookie)); - if (cookie) - page_put_link(NULL, cookie); + &done)); + do_delayed_call(&done); return res; } EXPORT_SYMBOL(page_readlink); @@ -4619,6 +4609,5 @@ EXPORT_SYMBOL(page_symlink); const struct inode_operations page_symlink_inode_operations = { .readlink = generic_readlink, .get_link = page_get_link, - .put_link = page_put_link, }; EXPORT_SYMBOL(page_symlink_inode_operations); diff --git a/fs/ncpfs/inode.c b/fs/ncpfs/inode.c index 3ab6cdbcde60..ce1eb3f9dfe8 100644 --- a/fs/ncpfs/inode.c +++ b/fs/ncpfs/inode.c @@ -245,7 +245,6 @@ static void ncp_set_attr(struct inode *inode, struct ncp_entry_info *nwinfo) static const struct inode_operations ncp_symlink_inode_operations = { .readlink = generic_readlink, .get_link = page_get_link, - .put_link = page_put_link, .setattr = ncp_notify_change, }; #endif diff --git a/fs/nfs/symlink.c b/fs/nfs/symlink.c index 95c69af7e4d0..4fe3eead3868 100644 --- a/fs/nfs/symlink.c +++ b/fs/nfs/symlink.c @@ -43,7 +43,8 @@ error: } static const char *nfs_get_link(struct dentry *dentry, - struct inode *inode, void **cookie) + struct inode *inode, + struct delayed_call *done) { struct page *page; void *err; @@ -68,7 +69,7 @@ static const char *nfs_get_link(struct dentry *dentry, if (IS_ERR(page)) return ERR_CAST(page); } - *cookie = page; + set_delayed_call(done, page_put_link, page); return page_address(page); } @@ -78,7 +79,6 @@ static const char *nfs_get_link(struct dentry *dentry, const struct inode_operations nfs_symlink_inode_operations = { .readlink = generic_readlink, .get_link = nfs_get_link, - .put_link = page_put_link, .getattr = nfs_getattr, .setattr = nfs_setattr, }; diff --git a/fs/nilfs2/namei.c b/fs/nilfs2/namei.c index 63dddb7d4b18..7ccdb961eea9 100644 --- a/fs/nilfs2/namei.c +++ b/fs/nilfs2/namei.c @@ -570,7 +570,6 @@ const struct inode_operations nilfs_special_inode_operations = { const struct inode_operations nilfs_symlink_inode_operations = { .readlink = generic_readlink, .get_link = page_get_link, - .put_link = page_put_link, .permission = nilfs_permission, }; diff --git a/fs/ocfs2/symlink.c b/fs/ocfs2/symlink.c index b4e79bc720f7..6c2a3e3c521c 100644 --- a/fs/ocfs2/symlink.c +++ b/fs/ocfs2/symlink.c @@ -89,7 +89,6 @@ const struct address_space_operations ocfs2_fast_symlink_aops = { const struct inode_operations ocfs2_symlink_inode_operations = { .readlink = generic_readlink, .get_link = page_get_link, - .put_link = page_put_link, .getattr = ocfs2_getattr, .setattr = ocfs2_setattr, .setxattr = generic_setxattr, diff --git a/fs/overlayfs/inode.c b/fs/overlayfs/inode.c index 38a0b8b9f8b9..964a60fa7afc 100644 --- a/fs/overlayfs/inode.c +++ b/fs/overlayfs/inode.c @@ -131,19 +131,12 @@ out_dput: return err; } - -struct ovl_link_data { - struct dentry *realdentry; - void *cookie; -}; - static const char *ovl_get_link(struct dentry *dentry, - struct inode *inode, void **cookie) + struct inode *inode, + struct delayed_call *done) { struct dentry *realdentry; struct inode *realinode; - struct ovl_link_data *data = NULL; - const char *ret; if (!dentry) return ERR_PTR(-ECHILD); @@ -154,38 +147,7 @@ static const char *ovl_get_link(struct dentry *dentry, if (WARN_ON(!realinode->i_op->get_link)) return ERR_PTR(-EPERM); - if (realinode->i_op->put_link) { - data = kmalloc(sizeof(struct ovl_link_data), GFP_KERNEL); - if (!data) - return ERR_PTR(-ENOMEM); - data->realdentry = realdentry; - } - - ret = realinode->i_op->get_link(realdentry, realinode, cookie); - if (IS_ERR_OR_NULL(ret)) { - kfree(data); - return ret; - } - - if (data) - data->cookie = *cookie; - - *cookie = data; - - return ret; -} - -static void ovl_put_link(struct inode *unused, void *c) -{ - struct inode *realinode; - struct ovl_link_data *data = c; - - if (!data) - return; - - realinode = data->realdentry->d_inode; - realinode->i_op->put_link(realinode, data->cookie); - kfree(data); + return realinode->i_op->get_link(realdentry, realinode, done); } static int ovl_readlink(struct dentry *dentry, char __user *buf, int bufsiz) @@ -383,7 +345,6 @@ static const struct inode_operations ovl_file_inode_operations = { static const struct inode_operations ovl_symlink_inode_operations = { .setattr = ovl_setattr, .get_link = ovl_get_link, - .put_link = ovl_put_link, .readlink = ovl_readlink, .getattr = ovl_getattr, .setxattr = ovl_setxattr, diff --git a/fs/proc/base.c b/fs/proc/base.c index 1a489e2b9768..71660bb9e9f7 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -1565,7 +1565,8 @@ static int proc_exe_link(struct dentry *dentry, struct path *exe_path) } static const char *proc_pid_get_link(struct dentry *dentry, - struct inode *inode, void **cookie) + struct inode *inode, + struct delayed_call *done) { struct path path; int error = -EACCES; @@ -1949,12 +1950,13 @@ struct map_files_info { */ static const char * proc_map_files_get_link(struct dentry *dentry, - struct inode *inode, void **cookie) + struct inode *inode, + struct delayed_call *done) { if (!capable(CAP_SYS_ADMIN)) return ERR_PTR(-EPERM); - return proc_pid_get_link(dentry, inode, NULL); + return proc_pid_get_link(dentry, inode, done); } /* diff --git a/fs/proc/inode.c b/fs/proc/inode.c index 10360b268794..d0e9b9b6223e 100644 --- a/fs/proc/inode.c +++ b/fs/proc/inode.c @@ -393,25 +393,25 @@ static const struct file_operations proc_reg_file_ops_no_compat = { }; #endif +static void proc_put_link(void *p) +{ + unuse_pde(p); +} + static const char *proc_get_link(struct dentry *dentry, - struct inode *inode, void **cookie) + struct inode *inode, + struct delayed_call *done) { struct proc_dir_entry *pde = PDE(inode); if (unlikely(!use_pde(pde))) return ERR_PTR(-EINVAL); - *cookie = pde; + set_delayed_call(done, proc_put_link, pde); return pde->data; } -static void proc_put_link(struct inode *unused, void *p) -{ - unuse_pde(p); -} - const struct inode_operations proc_link_inode_operations = { .readlink = generic_readlink, .get_link = proc_get_link, - .put_link = proc_put_link, }; struct inode *proc_get_inode(struct super_block *sb, struct proc_dir_entry *de) diff --git a/fs/proc/namespaces.c b/fs/proc/namespaces.c index 63861c15e109..1dece8781f91 100644 --- a/fs/proc/namespaces.c +++ b/fs/proc/namespaces.c @@ -31,7 +31,8 @@ static const struct proc_ns_operations *ns_entries[] = { }; static const char *proc_ns_get_link(struct dentry *dentry, - struct inode *inode, void **cookie) + struct inode *inode, + struct delayed_call *done) { const struct proc_ns_operations *ns_ops = PROC_I(inode)->ns_ops; struct task_struct *task; diff --git a/fs/proc/self.c b/fs/proc/self.c index 7a8b19ead3b6..67e8db442cf0 100644 --- a/fs/proc/self.c +++ b/fs/proc/self.c @@ -19,7 +19,8 @@ static int proc_self_readlink(struct dentry *dentry, char __user *buffer, } static const char *proc_self_get_link(struct dentry *dentry, - struct inode *inode, void **cookie) + struct inode *inode, + struct delayed_call *done) { struct pid_namespace *ns = inode->i_sb->s_fs_info; pid_t tgid = task_tgid_nr_ns(current, ns); @@ -32,13 +33,13 @@ static const char *proc_self_get_link(struct dentry *dentry, if (unlikely(!name)) return dentry ? ERR_PTR(-ENOMEM) : ERR_PTR(-ECHILD); sprintf(name, "%d", tgid); - return *cookie = name; + set_delayed_call(done, kfree_link, name); + return name; } static const struct inode_operations proc_self_inode_operations = { .readlink = proc_self_readlink, .get_link = proc_self_get_link, - .put_link = kfree_put_link, }; static unsigned self_inum; diff --git a/fs/proc/thread_self.c b/fs/proc/thread_self.c index 03eaa84604da..9eacd59e0360 100644 --- a/fs/proc/thread_self.c +++ b/fs/proc/thread_self.c @@ -20,7 +20,8 @@ static int proc_thread_self_readlink(struct dentry *dentry, char __user *buffer, } static const char *proc_thread_self_get_link(struct dentry *dentry, - struct inode *inode, void **cookie) + struct inode *inode, + struct delayed_call *done) { struct pid_namespace *ns = inode->i_sb->s_fs_info; pid_t tgid = task_tgid_nr_ns(current, ns); @@ -34,13 +35,13 @@ static const char *proc_thread_self_get_link(struct dentry *dentry, if (unlikely(!name)) return dentry ? ERR_PTR(-ENOMEM) : ERR_PTR(-ECHILD); sprintf(name, "%d/task/%d", tgid, pid); - return *cookie = name; + set_delayed_call(done, kfree_link, name); + return name; } static const struct inode_operations proc_thread_self_inode_operations = { .readlink = proc_thread_self_readlink, .get_link = proc_thread_self_get_link, - .put_link = kfree_put_link, }; static unsigned thread_self_inum; diff --git a/fs/reiserfs/namei.c b/fs/reiserfs/namei.c index ecbf11e961ab..2a12d46d7fb4 100644 --- a/fs/reiserfs/namei.c +++ b/fs/reiserfs/namei.c @@ -1666,7 +1666,6 @@ const struct inode_operations reiserfs_dir_inode_operations = { const struct inode_operations reiserfs_symlink_inode_operations = { .readlink = generic_readlink, .get_link = page_get_link, - .put_link = page_put_link, .setattr = reiserfs_setattr, .setxattr = reiserfs_setxattr, .getxattr = reiserfs_getxattr, diff --git a/fs/squashfs/symlink.c b/fs/squashfs/symlink.c index 7c635a5da783..dbcc2f54bad4 100644 --- a/fs/squashfs/symlink.c +++ b/fs/squashfs/symlink.c @@ -120,7 +120,6 @@ const struct address_space_operations squashfs_symlink_aops = { const struct inode_operations squashfs_symlink_inode_ops = { .readlink = generic_readlink, .get_link = page_get_link, - .put_link = page_put_link, .getxattr = generic_getxattr, .listxattr = squashfs_listxattr }; diff --git a/fs/sysv/inode.c b/fs/sysv/inode.c index 80a40bcb721c..07ac18c355e7 100644 --- a/fs/sysv/inode.c +++ b/fs/sysv/inode.c @@ -147,7 +147,6 @@ static inline void write3byte(struct sysv_sb_info *sbi, static const struct inode_operations sysv_symlink_inode_operations = { .readlink = generic_readlink, .get_link = page_get_link, - .put_link = page_put_link, .getattr = sysv_getattr, }; diff --git a/fs/xfs/xfs_iops.c b/fs/xfs/xfs_iops.c index f638fd58b5b3..06eafafe636e 100644 --- a/fs/xfs/xfs_iops.c +++ b/fs/xfs/xfs_iops.c @@ -417,7 +417,7 @@ STATIC const char * xfs_vn_get_link( struct dentry *dentry, struct inode *inode, - void **cookie) + struct delayed_call *done) { char *link; int error = -ENOMEM; @@ -433,7 +433,8 @@ xfs_vn_get_link( if (unlikely(error)) goto out_kfree; - return *cookie = link; + set_delayed_call(done, kfree_link, link); + return link; out_kfree: kfree(link); @@ -1177,7 +1178,6 @@ static const struct inode_operations xfs_dir_ci_inode_operations = { static const struct inode_operations xfs_symlink_inode_operations = { .readlink = generic_readlink, .get_link = xfs_vn_get_link, - .put_link = kfree_put_link, .getattr = xfs_vn_getattr, .setattr = xfs_vn_setattr, .setxattr = generic_setxattr, diff --git a/include/linux/delayed_call.h b/include/linux/delayed_call.h new file mode 100644 index 000000000000..f7fa76ae1a9b --- /dev/null +++ b/include/linux/delayed_call.h @@ -0,0 +1,34 @@ +#ifndef _DELAYED_CALL_H +#define _DELAYED_CALL_H + +/* + * Poor man's closures; I wish we could've done them sanely polymorphic, + * but... + */ + +struct delayed_call { + void (*fn)(void *); + void *arg; +}; + +#define DEFINE_DELAYED_CALL(name) struct delayed_call name = {NULL, NULL} + +/* I really wish we had closures with sane typechecking... */ +static inline void set_delayed_call(struct delayed_call *call, + void (*fn)(void *), void *arg) +{ + call->fn = fn; + call->arg = arg; +} + +static inline void do_delayed_call(struct delayed_call *call) +{ + if (call->fn) + call->fn(call->arg); +} + +static inline void clear_delayed_call(struct delayed_call *call) +{ + call->fn = NULL; +} +#endif diff --git a/include/linux/fs.h b/include/linux/fs.h index 138e206df2fc..5de5edb01e70 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -31,6 +31,7 @@ #include #include #include +#include #include #include @@ -1633,12 +1634,11 @@ struct file_operations { struct inode_operations { struct dentry * (*lookup) (struct inode *,struct dentry *, unsigned int); - const char * (*get_link) (struct dentry *, struct inode *, void **); + const char * (*get_link) (struct dentry *, struct inode *, struct delayed_call *); int (*permission) (struct inode *, int); struct posix_acl * (*get_acl)(struct inode *, int); int (*readlink) (struct dentry *, char __user *,int); - void (*put_link) (struct inode *, void *); int (*create) (struct inode *,struct dentry *, umode_t, bool); int (*link) (struct dentry *,struct inode *,struct dentry *); @@ -2736,13 +2736,14 @@ extern const struct file_operations generic_ro_fops; extern int readlink_copy(char __user *, int, const char *); extern int page_readlink(struct dentry *, char __user *, int); -extern const char *page_get_link(struct dentry *, struct inode *, void **); -extern void page_put_link(struct inode *, void *); +extern const char *page_get_link(struct dentry *, struct inode *, + struct delayed_call *); +extern void page_put_link(void *); extern int __page_symlink(struct inode *inode, const char *symname, int len, int nofs); extern int page_symlink(struct inode *inode, const char *symname, int len); extern const struct inode_operations page_symlink_inode_operations; -extern void kfree_put_link(struct inode *, void *); +extern void kfree_link(void *); extern int generic_readlink(struct dentry *, char __user *, int); extern void generic_fillattr(struct inode *, struct kstat *); int vfs_getattr_nosec(struct path *path, struct kstat *stat); @@ -2753,7 +2754,8 @@ void __inode_sub_bytes(struct inode *inode, loff_t bytes); void inode_sub_bytes(struct inode *inode, loff_t bytes); loff_t inode_get_bytes(struct inode *inode); void inode_set_bytes(struct inode *inode, loff_t bytes); -const char *simple_get_link(struct dentry *, struct inode *, void **); +const char *simple_get_link(struct dentry *, struct inode *, + struct delayed_call *); extern const struct inode_operations simple_symlink_inode_operations; extern int iterate_dir(struct file *, struct dir_context *); diff --git a/mm/shmem.c b/mm/shmem.c index 0605716aee06..bab9041b1967 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -2496,8 +2496,15 @@ static int shmem_symlink(struct inode *dir, struct dentry *dentry, const char *s return 0; } +static void shmem_put_link(void *arg) +{ + mark_page_accessed(arg); + put_page(arg); +} + static const char *shmem_get_link(struct dentry *dentry, - struct inode *inode, void **cookie) + struct inode *inode, + struct delayed_call *done) { struct page *page = NULL; int error; @@ -2515,17 +2522,10 @@ static const char *shmem_get_link(struct dentry *dentry, return ERR_PTR(error); unlock_page(page); } - *cookie = page; + set_delayed_call(done, shmem_put_link, page); return page_address(page); } -static void shmem_put_link(struct inode *unused, void *cookie) -{ - struct page *page = cookie; - mark_page_accessed(page); - page_cache_release(page); -} - #ifdef CONFIG_TMPFS_XATTR /* * Superblocks without xattr inode operations may get some security.* xattr @@ -2680,7 +2680,6 @@ static const struct inode_operations shmem_short_symlink_operations = { static const struct inode_operations shmem_symlink_inode_operations = { .readlink = generic_readlink, .get_link = shmem_get_link, - .put_link = shmem_put_link, #ifdef CONFIG_TMPFS_XATTR .setxattr = shmem_setxattr, .getxattr = shmem_getxattr, -- cgit v1.2.3 From 03607ace807b414eab46323c794b6fb8fcc2d48c Mon Sep 17 00:00:00 2001 From: Pantelis Antoniou Date: Thu, 22 Oct 2015 23:30:04 +0300 Subject: configfs: implement binary attributes ConfigFS lacked binary attributes up until now. This patch introduces support for binary attributes in a somewhat similar manner of sysfs binary attributes albeit with changes that fit the configfs usage model. Problems that configfs binary attributes fix are everything that requires a binary blob as part of the configuration of a resource, such as bitstream loading for FPGAs, DTBs for dynamically created devices etc. Look at Documentation/filesystems/configfs/configfs.txt for internals and howto use them. This patch is against linux-next as of today that contains Christoph's configfs rework. Signed-off-by: Pantelis Antoniou [hch: folded a fix from Geert Uytterhoeven ] [hch: a few tiny updates based on review feedback] Signed-off-by: Christoph Hellwig --- Documentation/filesystems/configfs/configfs.txt | 57 +++++- fs/configfs/configfs_internal.h | 14 +- fs/configfs/dir.c | 18 +- fs/configfs/file.c | 255 +++++++++++++++++++++++- fs/configfs/inode.c | 2 +- include/linux/configfs.h | 50 +++++ 6 files changed, 374 insertions(+), 22 deletions(-) (limited to 'Documentation/filesystems') diff --git a/Documentation/filesystems/configfs/configfs.txt b/Documentation/filesystems/configfs/configfs.txt index af68efdbbfad..e5fe521eea1d 100644 --- a/Documentation/filesystems/configfs/configfs.txt +++ b/Documentation/filesystems/configfs/configfs.txt @@ -51,15 +51,27 @@ configfs tree is always there, whether mounted on /config or not. An item is created via mkdir(2). The item's attributes will also appear at this time. readdir(3) can determine what the attributes are, read(2) can query their default values, and write(2) can store new -values. Like sysfs, attributes should be ASCII text files, preferably -with only one value per file. The same efficiency caveats from sysfs -apply. Don't mix more than one attribute in one attribute file. - -Like sysfs, configfs expects write(2) to store the entire buffer at -once. When writing to configfs attributes, userspace processes should -first read the entire file, modify the portions they wish to change, and -then write the entire buffer back. Attribute files have a maximum size -of one page (PAGE_SIZE, 4096 on i386). +values. Don't mix more than one attribute in one attribute file. + +There are two types of configfs attributes: + +* Normal attributes, which similar to sysfs attributes, are small ASCII text +files, with a maximum size of one page (PAGE_SIZE, 4096 on i386). Preferably +only one value per file should be used, and the same caveats from sysfs apply. +Configfs expects write(2) to store the entire buffer at once. When writing to +normal configfs attributes, userspace processes should first read the entire +file, modify the portions they wish to change, and then write the entire +buffer back. + +* Binary attributes, which are somewhat similar to sysfs binary attributes, +but with a few slight changes to semantics. The PAGE_SIZE limitation does not +apply, but the whole binary item must fit in single kernel vmalloc'ed buffer. +The write(2) calls from user space are buffered, and the attributes' +write_bin_attribute method will be invoked on the final close, therefore it is +imperative for user-space to check the return code of close(2) in order to +verify that the operation finished successfully. +To avoid a malicious user OOMing the kernel, there's a per-binary attribute +maximum buffer value. When an item needs to be destroyed, remove it with rmdir(2). An item cannot be destroyed if any other item has a link to it (via @@ -171,6 +183,7 @@ among other things. For that, it needs a type. struct configfs_item_operations *ct_item_ops; struct configfs_group_operations *ct_group_ops; struct configfs_attribute **ct_attrs; + struct configfs_bin_attribute **ct_bin_attrs; }; The most basic function of a config_item_type is to define what @@ -201,6 +214,32 @@ be called whenever userspace asks for a read(2) on the attribute. If an attribute is writable and provides a ->store method, that method will be be called whenever userspace asks for a write(2) on the attribute. +[struct configfs_bin_attribute] + + struct configfs_attribute { + struct configfs_attribute cb_attr; + void *cb_private; + size_t cb_max_size; + }; + +The binary attribute is used when the one needs to use binary blob to +appear as the contents of a file in the item's configfs directory. +To do so add the binary attribute to the NULL-terminated array +config_item_type->ct_bin_attrs, and the item appears in configfs, the +attribute file will appear with the configfs_bin_attribute->cb_attr.ca_name +filename. configfs_bin_attribute->cb_attr.ca_mode specifies the file +permissions. +The cb_private member is provided for use by the driver, while the +cb_max_size member specifies the maximum amount of vmalloc buffer +to be used. + +If binary attribute is readable and the config_item provides a +ct_item_ops->read_bin_attribute() method, that method will be called +whenever userspace asks for a read(2) on the attribute. The converse +will happen for write(2). The reads/writes are bufferred so only a +single read/write will occur; the attributes' need not concern itself +with it. + [struct config_group] A config_item cannot live in a vacuum. The only way one can be created diff --git a/fs/configfs/configfs_internal.h b/fs/configfs/configfs_internal.h index b65d1ef532d5..ccc31fa6f1a7 100644 --- a/fs/configfs/configfs_internal.h +++ b/fs/configfs/configfs_internal.h @@ -53,13 +53,14 @@ struct configfs_dirent { #define CONFIGFS_ROOT 0x0001 #define CONFIGFS_DIR 0x0002 #define CONFIGFS_ITEM_ATTR 0x0004 +#define CONFIGFS_ITEM_BIN_ATTR 0x0008 #define CONFIGFS_ITEM_LINK 0x0020 #define CONFIGFS_USET_DIR 0x0040 #define CONFIGFS_USET_DEFAULT 0x0080 #define CONFIGFS_USET_DROPPING 0x0100 #define CONFIGFS_USET_IN_MKDIR 0x0200 #define CONFIGFS_USET_CREATING 0x0400 -#define CONFIGFS_NOT_PINNED (CONFIGFS_ITEM_ATTR) +#define CONFIGFS_NOT_PINNED (CONFIGFS_ITEM_ATTR | CONFIGFS_ITEM_BIN_ATTR) extern struct mutex configfs_symlink_mutex; extern spinlock_t configfs_dirent_lock; @@ -72,6 +73,8 @@ extern struct inode * configfs_new_inode(umode_t mode, struct configfs_dirent *, extern int configfs_create(struct dentry *, umode_t mode, void (*init)(struct inode *)); extern int configfs_create_file(struct config_item *, const struct configfs_attribute *); +extern int configfs_create_bin_file(struct config_item *, + const struct configfs_bin_attribute *); extern int configfs_make_dirent(struct configfs_dirent *, struct dentry *, void *, umode_t, int); extern int configfs_dirent_is_ready(struct configfs_dirent *); @@ -88,7 +91,7 @@ extern void configfs_release_fs(void); extern struct rw_semaphore configfs_rename_sem; extern const struct file_operations configfs_dir_operations; extern const struct file_operations configfs_file_operations; -extern const struct file_operations bin_fops; +extern const struct file_operations configfs_bin_file_operations; extern const struct inode_operations configfs_dir_inode_operations; extern const struct inode_operations configfs_root_inode_operations; extern const struct inode_operations configfs_symlink_inode_operations; @@ -119,6 +122,13 @@ static inline struct configfs_attribute * to_attr(struct dentry * dentry) return ((struct configfs_attribute *) sd->s_element); } +static inline struct configfs_bin_attribute *to_bin_attr(struct dentry *dentry) +{ + struct configfs_attribute *attr = to_attr(dentry); + + return container_of(attr, struct configfs_bin_attribute, cb_attr); +} + static inline struct config_item *configfs_get_config_item(struct dentry *dentry) { struct config_item * item = NULL; diff --git a/fs/configfs/dir.c b/fs/configfs/dir.c index a7a1b218f308..7ae97e83f121 100644 --- a/fs/configfs/dir.c +++ b/fs/configfs/dir.c @@ -255,6 +255,12 @@ static void configfs_init_file(struct inode * inode) inode->i_fop = &configfs_file_operations; } +static void configfs_init_bin_file(struct inode *inode) +{ + inode->i_size = 0; + inode->i_fop = &configfs_bin_file_operations; +} + static void init_symlink(struct inode * inode) { inode->i_op = &configfs_symlink_inode_operations; @@ -423,7 +429,9 @@ static int configfs_attach_attr(struct configfs_dirent * sd, struct dentry * den spin_unlock(&configfs_dirent_lock); error = configfs_create(dentry, (attr->ca_mode & S_IALLUGO) | S_IFREG, - configfs_init_file); + (sd->s_type & CONFIGFS_ITEM_BIN_ATTR) ? + configfs_init_bin_file : + configfs_init_file); if (error) { configfs_put(sd); return error; @@ -583,6 +591,7 @@ static int populate_attrs(struct config_item *item) { struct config_item_type *t = item->ci_type; struct configfs_attribute *attr; + struct configfs_bin_attribute *bin_attr; int error = 0; int i; @@ -594,6 +603,13 @@ static int populate_attrs(struct config_item *item) break; } } + if (t->ct_bin_attrs) { + for (i = 0; (bin_attr = t->ct_bin_attrs[i]) != NULL; i++) { + error = configfs_create_bin_file(item, bin_attr); + if (error) + break; + } + } if (error) detach_attrs(item); diff --git a/fs/configfs/file.c b/fs/configfs/file.c index d39099ea7df7..3687187c8ea5 100644 --- a/fs/configfs/file.c +++ b/fs/configfs/file.c @@ -28,6 +28,7 @@ #include #include #include +#include #include #include @@ -48,6 +49,10 @@ struct configfs_buffer { struct configfs_item_operations * ops; struct mutex mutex; int needs_read_fill; + bool read_in_progress; + bool write_in_progress; + char *bin_buffer; + int bin_buffer_size; }; @@ -123,6 +128,87 @@ out: return retval; } +/** + * configfs_read_bin_file - read a binary attribute. + * @file: file pointer. + * @buf: buffer to fill. + * @count: number of bytes to read. + * @ppos: starting offset in file. + * + * Userspace wants to read a binary attribute file. The attribute + * descriptor is in the file's ->d_fsdata. The target item is in the + * directory's ->d_fsdata. + * + * We check whether we need to refill the buffer. If so we will + * call the attributes' attr->read() twice. The first time we + * will pass a NULL as a buffer pointer, which the attributes' method + * will use to return the size of the buffer required. If no error + * occurs we will allocate the buffer using vmalloc and call + * attr->read() again passing that buffer as an argument. + * Then we just copy to user-space using simple_read_from_buffer. + */ + +static ssize_t +configfs_read_bin_file(struct file *file, char __user *buf, + size_t count, loff_t *ppos) +{ + struct configfs_buffer *buffer = file->private_data; + struct dentry *dentry = file->f_path.dentry; + struct config_item *item = to_item(dentry->d_parent); + struct configfs_bin_attribute *bin_attr = to_bin_attr(dentry); + ssize_t retval = 0; + ssize_t len = min_t(size_t, count, PAGE_SIZE); + + mutex_lock(&buffer->mutex); + + /* we don't support switching read/write modes */ + if (buffer->write_in_progress) { + retval = -ETXTBSY; + goto out; + } + buffer->read_in_progress = 1; + + if (buffer->needs_read_fill) { + /* perform first read with buf == NULL to get extent */ + len = bin_attr->read(item, NULL, 0); + if (len <= 0) { + retval = len; + goto out; + } + + /* do not exceed the maximum value */ + if (bin_attr->cb_max_size && len > bin_attr->cb_max_size) { + retval = -EFBIG; + goto out; + } + + buffer->bin_buffer = vmalloc(len); + if (buffer->bin_buffer == NULL) { + retval = -ENOMEM; + goto out; + } + buffer->bin_buffer_size = len; + + /* perform second read to fill buffer */ + len = bin_attr->read(item, buffer->bin_buffer, len); + if (len < 0) { + retval = len; + vfree(buffer->bin_buffer); + buffer->bin_buffer_size = 0; + buffer->bin_buffer = NULL; + goto out; + } + + buffer->needs_read_fill = 0; + } + + retval = simple_read_from_buffer(buf, count, ppos, buffer->bin_buffer, + buffer->bin_buffer_size); +out: + mutex_unlock(&buffer->mutex); + return retval; +} + /** * fill_write_buffer - copy buffer from userspace. @@ -209,10 +295,80 @@ configfs_write_file(struct file *file, const char __user *buf, size_t count, lof return len; } -static int check_perm(struct inode * inode, struct file * file) +/** + * configfs_write_bin_file - write a binary attribute. + * @file: file pointer + * @buf: data to write + * @count: number of bytes + * @ppos: starting offset + * + * Writing to a binary attribute file is similar to a normal read. + * We buffer the consecutive writes (binary attribute files do not + * support lseek) in a continuously growing buffer, but we don't + * commit until the close of the file. + */ + +static ssize_t +configfs_write_bin_file(struct file *file, const char __user *buf, + size_t count, loff_t *ppos) +{ + struct configfs_buffer *buffer = file->private_data; + struct dentry *dentry = file->f_path.dentry; + struct configfs_bin_attribute *bin_attr = to_bin_attr(dentry); + void *tbuf = NULL; + ssize_t len; + + mutex_lock(&buffer->mutex); + + /* we don't support switching read/write modes */ + if (buffer->read_in_progress) { + len = -ETXTBSY; + goto out; + } + buffer->write_in_progress = 1; + + /* buffer grows? */ + if (*ppos + count > buffer->bin_buffer_size) { + + if (bin_attr->cb_max_size && + *ppos + count > bin_attr->cb_max_size) { + len = -EFBIG; + } + + tbuf = vmalloc(*ppos + count); + if (tbuf == NULL) { + len = -ENOMEM; + goto out; + } + + /* copy old contents */ + if (buffer->bin_buffer) { + memcpy(tbuf, buffer->bin_buffer, + buffer->bin_buffer_size); + vfree(buffer->bin_buffer); + } + + /* clear the new area */ + memset(tbuf + buffer->bin_buffer_size, 0, + *ppos + count - buffer->bin_buffer_size); + buffer->bin_buffer = tbuf; + buffer->bin_buffer_size = *ppos + count; + } + + len = simple_write_to_buffer(buffer->bin_buffer, + buffer->bin_buffer_size, ppos, buf, count); + if (len > 0) + *ppos += len; +out: + mutex_unlock(&buffer->mutex); + return len; +} + +static int check_perm(struct inode * inode, struct file * file, int type) { struct config_item *item = configfs_get_config_item(file->f_path.dentry->d_parent); struct configfs_attribute * attr = to_attr(file->f_path.dentry); + struct configfs_bin_attribute *bin_attr = NULL; struct configfs_buffer * buffer; struct configfs_item_operations * ops = NULL; int error = 0; @@ -220,6 +376,9 @@ static int check_perm(struct inode * inode, struct file * file) if (!item || !attr) goto Einval; + if (type & CONFIGFS_ITEM_BIN_ATTR) + bin_attr = to_bin_attr(file->f_path.dentry); + /* Grab the module reference for this attribute if we have one */ if (!try_module_get(attr->ca_owner)) { error = -ENODEV; @@ -236,9 +395,14 @@ static int check_perm(struct inode * inode, struct file * file) * and we must have a store method. */ if (file->f_mode & FMODE_WRITE) { - if (!(inode->i_mode & S_IWUGO) || !attr->store) + if (!(inode->i_mode & S_IWUGO)) + goto Eaccess; + + if ((type & CONFIGFS_ITEM_ATTR) && !attr->store) goto Eaccess; + if ((type & CONFIGFS_ITEM_BIN_ATTR) && !bin_attr->write) + goto Eaccess; } /* File needs read support. @@ -246,7 +410,13 @@ static int check_perm(struct inode * inode, struct file * file) * must be a show method for it. */ if (file->f_mode & FMODE_READ) { - if (!(inode->i_mode & S_IRUGO) || !attr->show) + if (!(inode->i_mode & S_IRUGO)) + goto Eaccess; + + if ((type & CONFIGFS_ITEM_ATTR) && !attr->show) + goto Eaccess; + + if ((type & CONFIGFS_ITEM_BIN_ATTR) && !bin_attr->read) goto Eaccess; } @@ -260,6 +430,8 @@ static int check_perm(struct inode * inode, struct file * file) } mutex_init(&buffer->mutex); buffer->needs_read_fill = 1; + buffer->read_in_progress = 0; + buffer->write_in_progress = 0; buffer->ops = ops; file->private_data = buffer; goto Done; @@ -277,12 +449,7 @@ static int check_perm(struct inode * inode, struct file * file) return error; } -static int configfs_open_file(struct inode * inode, struct file * filp) -{ - return check_perm(inode,filp); -} - -static int configfs_release(struct inode * inode, struct file * filp) +static int configfs_release(struct inode *inode, struct file *filp) { struct config_item * item = to_item(filp->f_path.dentry->d_parent); struct configfs_attribute * attr = to_attr(filp->f_path.dentry); @@ -303,6 +470,47 @@ static int configfs_release(struct inode * inode, struct file * filp) return 0; } +static int configfs_open_file(struct inode *inode, struct file *filp) +{ + return check_perm(inode, filp, CONFIGFS_ITEM_ATTR); +} + +static int configfs_open_bin_file(struct inode *inode, struct file *filp) +{ + return check_perm(inode, filp, CONFIGFS_ITEM_BIN_ATTR); +} + +static int configfs_release_bin_file(struct inode *inode, struct file *filp) +{ + struct configfs_buffer *buffer = filp->private_data; + struct dentry *dentry = filp->f_path.dentry; + struct config_item *item = to_item(dentry->d_parent); + struct configfs_bin_attribute *bin_attr = to_bin_attr(dentry); + ssize_t len = 0; + int ret; + + buffer->read_in_progress = 0; + + if (buffer->write_in_progress) { + buffer->write_in_progress = 0; + + len = bin_attr->write(item, buffer->bin_buffer, + buffer->bin_buffer_size); + + /* vfree on NULL is safe */ + vfree(buffer->bin_buffer); + buffer->bin_buffer = NULL; + buffer->bin_buffer_size = 0; + buffer->needs_read_fill = 1; + } + + ret = configfs_release(inode, filp); + if (len < 0) + return len; + return ret; +} + + const struct file_operations configfs_file_operations = { .read = configfs_read_file, .write = configfs_write_file, @@ -311,6 +519,14 @@ const struct file_operations configfs_file_operations = { .release = configfs_release, }; +const struct file_operations configfs_bin_file_operations = { + .read = configfs_read_bin_file, + .write = configfs_write_bin_file, + .llseek = NULL, /* bin file is not seekable */ + .open = configfs_open_bin_file, + .release = configfs_release_bin_file, +}; + /** * configfs_create_file - create an attribute file for an item. * @item: item we're creating for. @@ -332,3 +548,24 @@ int configfs_create_file(struct config_item * item, const struct configfs_attrib return error; } +/** + * configfs_create_bin_file - create a binary attribute file for an item. + * @item: item we're creating for. + * @attr: atrribute descriptor. + */ + +int configfs_create_bin_file(struct config_item *item, + const struct configfs_bin_attribute *bin_attr) +{ + struct dentry *dir = item->ci_dentry; + struct configfs_dirent *parent_sd = dir->d_fsdata; + umode_t mode = (bin_attr->cb_attr.ca_mode & S_IALLUGO) | S_IFREG; + int error = 0; + + mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_NORMAL); + error = configfs_make_dirent(parent_sd, NULL, (void *) bin_attr, mode, + CONFIGFS_ITEM_BIN_ATTR); + mutex_unlock(&dir->d_inode->i_mutex); + + return error; +} diff --git a/fs/configfs/inode.c b/fs/configfs/inode.c index eae87575e681..0cc810e9dccc 100644 --- a/fs/configfs/inode.c +++ b/fs/configfs/inode.c @@ -218,7 +218,7 @@ const unsigned char * configfs_get_name(struct configfs_dirent *sd) if (sd->s_type & (CONFIGFS_DIR | CONFIGFS_ITEM_LINK)) return sd->s_dentry->d_name.name; - if (sd->s_type & CONFIGFS_ITEM_ATTR) { + if (sd->s_type & (CONFIGFS_ITEM_ATTR | CONFIGFS_ITEM_BIN_ATTR)) { attr = sd->s_element; return attr->ca_name; } diff --git a/include/linux/configfs.h b/include/linux/configfs.h index 758a029011b1..f7300d023dbe 100644 --- a/include/linux/configfs.h +++ b/include/linux/configfs.h @@ -51,6 +51,7 @@ struct module; struct configfs_item_operations; struct configfs_group_operations; struct configfs_attribute; +struct configfs_bin_attribute; struct configfs_subsystem; struct config_item { @@ -84,6 +85,7 @@ struct config_item_type { struct configfs_item_operations *ct_item_ops; struct configfs_group_operations *ct_group_ops; struct configfs_attribute **ct_attrs; + struct configfs_bin_attribute **ct_bin_attrs; }; /** @@ -154,6 +156,54 @@ static struct configfs_attribute _pfx##attr_##_name = { \ .store = _pfx##_name##_store, \ } +struct file; +struct vm_area_struct; + +struct configfs_bin_attribute { + struct configfs_attribute cb_attr; /* std. attribute */ + void *cb_private; /* for user */ + size_t cb_max_size; /* max core size */ + ssize_t (*read)(struct config_item *, void *, size_t); + ssize_t (*write)(struct config_item *, const void *, size_t); +}; + +#define CONFIGFS_BIN_ATTR(_pfx, _name, _priv, _maxsz) \ +static struct configfs_bin_attribute _pfx##attr_##_name = { \ + .cb_attr = { \ + .ca_name = __stringify(_name), \ + .ca_mode = S_IRUGO | S_IWUSR, \ + .ca_owner = THIS_MODULE, \ + }, \ + .cb_private = _priv, \ + .cb_max_size = _maxsz, \ + .read = _pfx##_name##_read, \ + .write = _pfx##_name##_write, \ +} + +#define CONFIGFS_BIN_ATTR_RO(_pfx, _name, _priv, _maxsz) \ +static struct configfs_attribute _pfx##attr_##_name = { \ + .cb_attr = { \ + .ca_name = __stringify(_name), \ + .ca_mode = S_IRUGO, \ + .ca_owner = THIS_MODULE, \ + }, \ + .cb_private = _priv, \ + .cb_max_size = _maxsz, \ + .read = _pfx##_name##_read, \ +} + +#define CONFIGFS_BIN_ATTR_WO(_pfx, _name, _priv, _maxsz) \ +static struct configfs_attribute _pfx##attr_##_name = { \ + .cb_attr = { \ + .ca_name = __stringify(_name), \ + .ca_mode = S_IWUSR, \ + .ca_owner = THIS_MODULE, \ + }, \ + .cb_private = _priv, \ + .cb_max_size = _maxsz, \ + .write = _pfx##_name##_write, \ +} + /* * If allow_link() exists, the item can symlink(2) out to other * items. If the item is a group, it may support mkdir(2). -- cgit v1.2.3 From ceec86ec06177f9eca684a489ddf630432023284 Mon Sep 17 00:00:00 2001 From: SeongJae Park Date: Wed, 13 Jan 2016 16:47:56 +0900 Subject: Documentation: update libhugetlbfs site url The site for libhugetlbfs has moved from sourceforge to github. This commit updates the old url. Signed-off-by: SeongJae Park Acked-by: Mike Kravetz Signed-off-by: Jonathan Corbet --- Documentation/filesystems/proc.txt | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'Documentation/filesystems') diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt index 402ab99e409f..5d4f28a33ad3 100644 --- a/Documentation/filesystems/proc.txt +++ b/Documentation/filesystems/proc.txt @@ -807,7 +807,7 @@ by migrate-type and finishes with details on how many page blocks of each type exist. If min_free_kbytes has been tuned correctly (recommendations made by hugeadm -from libhugetlbfs http://sourceforge.net/projects/libhugetlbfs/), one can +from libhugetlbfs https://github.com/libhugetlbfs/libhugetlbfs/), one can make an estimate of the likely number of huge pages that can be allocated at a given point in time. All the "Movable" blocks should be allocatable unless memory has been mlock()'d. Some of the Reclaimable blocks should -- cgit v1.2.3 From e8ecde25f5e08f89b61d86c32bbb56b405e90c32 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Thu, 14 Jan 2016 17:52:59 -0500 Subject: Make sure that highmem pages are not added to symlink page cache inode_nohighmem() is sufficient to make sure that page_get_link() won't try to allocate a highmem page. Moreover, it is sufficient to make sure that page_symlink/__page_symlink won't do the same thing. However, any filesystem that manually preseeds the symlink's page cache upon symlink(2) needs to make sure that the page it inserts there won't be a highmem one. Fortunately, only nfs and shmem have run afoul of that... Signed-off-by: Al Viro --- Documentation/filesystems/porting | 6 +++++- fs/nfs/dir.c | 5 ++--- mm/shmem.c | 2 +- 3 files changed, 8 insertions(+), 5 deletions(-) (limited to 'Documentation/filesystems') diff --git a/Documentation/filesystems/porting b/Documentation/filesystems/porting index 0f88e6020487..f1b87d8aa2da 100644 --- a/Documentation/filesystems/porting +++ b/Documentation/filesystems/porting @@ -508,7 +508,11 @@ in your dentry operations instead. [mandatory] any symlink that might use page_follow_link_light/page_put_link() must have inode_nohighmem(inode) called before anything might start playing with - its pagecache. + its pagecache. No highmem pages should end up in the pagecache of such + symlinks. That includes any preseeding that might be done during symlink + creation. __page_symlink() will honour the mapping gfp flags, so once + you've done inode_nohighmem() it's safe to use, but if you allocate and + insert the page manually, make sure to use the right gfp flags. -- [mandatory] ->follow_link() is replaced with ->get_link(); same API, except that diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c index ce5a21861074..8a0530921685 100644 --- a/fs/nfs/dir.c +++ b/fs/nfs/dir.c @@ -1894,15 +1894,14 @@ int nfs_symlink(struct inode *dir, struct dentry *dentry, const char *symname) attr.ia_mode = S_IFLNK | S_IRWXUGO; attr.ia_valid = ATTR_MODE; - page = alloc_page(GFP_HIGHUSER); + page = alloc_page(GFP_USER); if (!page) return -ENOMEM; - kaddr = kmap_atomic(page); + kaddr = page_address(page); memcpy(kaddr, symname, pathlen); if (pathlen < PAGE_SIZE) memset(kaddr + pathlen, 0, PAGE_SIZE - pathlen); - kunmap_atomic(kaddr); trace_nfs_symlink_enter(dir, dentry); error = NFS_PROTO(dir)->symlink(dir, dentry, page, pathlen, &attr); diff --git a/mm/shmem.c b/mm/shmem.c index 5813b7fa85b6..642471b0ddea 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -2469,6 +2469,7 @@ static int shmem_symlink(struct inode *dir, struct dentry *dentry, const char *s inode->i_op = &shmem_short_symlink_operations; inode->i_link = info->symlink; } else { + inode_nohighmem(inode); error = shmem_getpage(inode, 0, &page, SGP_WRITE, NULL); if (error) { iput(inode); @@ -2476,7 +2477,6 @@ static int shmem_symlink(struct inode *dir, struct dentry *dentry, const char *s } inode->i_mapping->a_ops = &shmem_aops; inode->i_op = &shmem_symlink_inode_operations; - inode_nohighmem(inode); memcpy(page_address(page), symname, len); SetPageUptodate(page); set_page_dirty(page); -- cgit v1.2.3 From bf9683d6990589390b5178dafe8fd06808869293 Mon Sep 17 00:00:00 2001 From: Vlastimil Babka Date: Thu, 14 Jan 2016 15:19:14 -0800 Subject: mm, documentation: clarify /proc/pid/status VmSwap limitations for shmem This series is based on Jerome Marchand's [1] so let me quote the first paragraph from there: There are several shortcomings with the accounting of shared memory (sysV shm, shared anonymous mapping, mapping to a tmpfs file). The values in /proc//status and statm don't allow to distinguish between shmem memory and a shared mapping to a regular file, even though their implications on memory usage are quite different: at reclaim, file mapping can be dropped or written back on disk while shmem needs a place in swap. As for shmem pages that are swapped-out or in swap cache, they aren't accounted at all. The original motivation for myself is that a customer found (IMHO rightfully) confusing that e.g. top output for process swap usage is unreliable with respect to swapped out shmem pages, which are not accounted for. The fundamental difference between private anonymous and shmem pages is that the latter has PTE's converted to pte_none, and not swapents. As such, they are not accounted to the number of swapents visible e.g. in /proc/pid/status VmSwap row. It might be theoretically possible to use swapents when swapping out shmem (without extra cost, as one has to change all mappers anyway), and on swap in only convert the swapent for the faulting process, leaving swapents in other processes until they also fault (so again no extra cost). But I don't know how many assumptions this would break, and it would be too disruptive change for a relatively small benefit. Instead, my approach is to document the limitation of VmSwap, and provide means to determine the swap usage for shmem areas for those who are interested and willing to pay the price, using /proc/pid/smaps. Because outside of ipcs, I don't think it's possible to currently to determine the usage at all. The previous patchset [1] did introduce new shmem-specific fields into smaps output, and functions to determine the values. I take a simpler approach, noting that smaps output already has a "Swap: X kB" line, where currently X == 0 always for shmem areas. I think we can just consider this a bug and provide the proper value by consulting the radix tree, as e.g. mincore_page() does. In the patch changelog I explain why this is also not perfect (and cannot be without swapents), but still arguably much better than showing a 0. The last two patches are adapted from Jerome's patchset and provide a VmRSS breakdown to RssAnon, RssFile and RssShm in /proc/pid/status. Hugh noted that this is a welcome addition, and I agree that it might help e.g. debugging process memory usage at albeit non-zero, but still rather low cost of extra per-mm counter and some page flag checks. [1] http://lwn.net/Articles/611966/ This patch (of 6): The documentation for /proc/pid/status does not mention that the value of VmSwap counts only swapped out anonymous private pages, and not swapped out pages of the underlying shmem objects (for shmem mappings). This is not obvious, so document this limitation. Signed-off-by: Vlastimil Babka Acked-by: Konstantin Khlebnikov Acked-by: Michal Hocko Acked-by: Jerome Marchand Acked-by: Hugh Dickins Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/filesystems/proc.txt | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'Documentation/filesystems') diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt index 402ab99e409f..9f13b6e28676 100644 --- a/Documentation/filesystems/proc.txt +++ b/Documentation/filesystems/proc.txt @@ -238,7 +238,8 @@ Table 1-2: Contents of the status files (as of 4.1) VmLib size of shared library code VmPTE size of page table entries VmPMD size of second level page tables - VmSwap size of swap usage (the number of referred swapents) + VmSwap amount of swap used by anonymous private data + (shmem swap usage is not included) HugetlbPages size of hugetlb memory portions Threads number of threads SigQ number of signals queued/max. number for queue -- cgit v1.2.3 From c261e7d94f0dd33a34b6cf98686e8b9699b62340 Mon Sep 17 00:00:00 2001 From: Vlastimil Babka Date: Thu, 14 Jan 2016 15:19:17 -0800 Subject: mm, proc: account for shmem swap in /proc/pid/smaps Currently, /proc/pid/smaps will always show "Swap: 0 kB" for shmem-backed mappings, even if the mapped portion does contain pages that were swapped out. This is because unlike private anonymous mappings, shmem does not change pte to swap entry, but pte_none when swapping the page out. In the smaps page walk, such page thus looks like it was never faulted in. This patch changes smaps_pte_entry() to determine the swap status for such pte_none entries for shmem mappings, similarly to how mincore_page() does it. Swapped out shmem pages are thus accounted for. For private mappings of tmpfs files that COWed some of the pages, swaped out status of the original shmem pages is naturally ignored. If some of the private copies was also swapped out, they are accounted via their page table swap entries, so the resulting reported swap usage is then a sum of both swapped out private copies, and swapped out shmem pages that were not COWed. No double accounting can thus happen. The accounting is arguably still not as precise as for private anonymous mappings, since now we will count also pages that the process in question never accessed, but another process populated them and then let them become swapped out. I believe it is still less confusing and subtle than not showing any swap usage by shmem mappings at all. Swapped out counter might of interest of users who would like to prevent from future swapins during performance critical operation and pre-fault them at their convenience. Especially for larger swapped out regions the cost of swapin is much higher than a fresh page allocation. So a differentiation between pte_none vs. swapped out is important for those usecases. One downside of this patch is that it makes /proc/pid/smaps more expensive for shmem mappings, as we consult the radix tree for each pte_none entry, so the overal complexity is O(n*log(n)). I have measured this on a process that creates a 2GB mapping and dirties single pages with a stride of 2MB, and time how long does it take to cat /proc/pid/smaps of this process 100 times. Private anonymous mapping: real 0m0.949s user 0m0.116s sys 0m0.348s Mapping of a /dev/shm/file: real 0m3.831s user 0m0.180s sys 0m3.212s The difference is rather substantial, so the next patch will reduce the cost for shared or read-only mappings. In a less controlled experiment, I've gathered pids of processes on my desktop that have either '/dev/shm/*' or 'SYSV*' in smaps. This included the Chrome browser and some KDE processes. Again, I've run cat /proc/pid/smaps on each 100 times. Before this patch: real 0m9.050s user 0m0.518s sys 0m8.066s After this patch: real 0m9.221s user 0m0.541s sys 0m8.187s This suggests low impact on average systems. Note that this patch doesn't attempt to adjust the SwapPss field for shmem mappings, which would need extra work to determine who else could have the pages mapped. Thus the value stays zero except for COWed swapped out pages in a shmem mapping, which are accounted as usual. Signed-off-by: Vlastimil Babka Acked-by: Konstantin Khlebnikov Acked-by: Jerome Marchand Acked-by: Michal Hocko Cc: Hugh Dickins Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/filesystems/proc.txt | 5 +++- fs/proc/task_mmu.c | 51 ++++++++++++++++++++++++++++++++++++++ 2 files changed, 55 insertions(+), 1 deletion(-) (limited to 'Documentation/filesystems') diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt index 9f13b6e28676..fdeb5b33349f 100644 --- a/Documentation/filesystems/proc.txt +++ b/Documentation/filesystems/proc.txt @@ -460,7 +460,10 @@ and a page is modified, the file page is replaced by a private anonymous copy. hugetlbfs page which is *not* counted in "RSS" or "PSS" field for historical reasons. And these are not included in {Shared,Private}_{Clean,Dirty} field. "Swap" shows how much would-be-anonymous memory is also used, but out on swap. -"SwapPss" shows proportional swap share of this mapping. +For shmem mappings, "Swap" includes also the size of the mapped (and not +replaced by copy-on-write) part of the underlying shmem object out on swap. +"SwapPss" shows proportional swap share of this mapping. Unlike "Swap", this +does not take into account swapped out page of underlying shmem objects. "Locked" indicates whether the mapping is locked in memory or not. "VmFlags" field deserves a separate description. This member represents the kernel diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c index 187b3b5f242e..85ef60fdf2c0 100644 --- a/fs/proc/task_mmu.c +++ b/fs/proc/task_mmu.c @@ -451,6 +451,7 @@ struct mem_size_stats { unsigned long private_hugetlb; u64 pss; u64 swap_pss; + bool check_shmem_swap; }; static void smaps_account(struct mem_size_stats *mss, struct page *page, @@ -485,6 +486,45 @@ static void smaps_account(struct mem_size_stats *mss, struct page *page, } } +#ifdef CONFIG_SHMEM +static unsigned long smaps_shmem_swap(struct vm_area_struct *vma, + unsigned long addr) +{ + struct page *page; + + page = find_get_entry(vma->vm_file->f_mapping, + linear_page_index(vma, addr)); + if (!page) + return 0; + + if (radix_tree_exceptional_entry(page)) + return PAGE_SIZE; + + page_cache_release(page); + return 0; + +} + +static int smaps_pte_hole(unsigned long addr, unsigned long end, + struct mm_walk *walk) +{ + struct mem_size_stats *mss = walk->private; + + while (addr < end) { + mss->swap += smaps_shmem_swap(walk->vma, addr); + addr += PAGE_SIZE; + } + + return 0; +} +#else +static unsigned long smaps_shmem_swap(struct vm_area_struct *vma, + unsigned long addr) +{ + return 0; +} +#endif + static void smaps_pte_entry(pte_t *pte, unsigned long addr, struct mm_walk *walk) { @@ -512,6 +552,9 @@ static void smaps_pte_entry(pte_t *pte, unsigned long addr, } } else if (is_migration_entry(swpent)) page = migration_entry_to_page(swpent); + } else if (unlikely(IS_ENABLED(CONFIG_SHMEM) && mss->check_shmem_swap + && pte_none(*pte))) { + mss->swap += smaps_shmem_swap(vma, addr); } if (!page) @@ -671,6 +714,14 @@ static int show_smap(struct seq_file *m, void *v, int is_pid) }; memset(&mss, 0, sizeof mss); + +#ifdef CONFIG_SHMEM + if (vma->vm_file && shmem_mapping(vma->vm_file->f_mapping)) { + mss.check_shmem_swap = true; + smaps_walk.pte_hole = smaps_pte_hole; + } +#endif + /* mmap_sem is held in m_start */ walk_page_vma(vma, &smaps_walk); -- cgit v1.2.3 From 8cee852ec53fb530f10ccabf1596734209ae336b Mon Sep 17 00:00:00 2001 From: Jerome Marchand Date: Thu, 14 Jan 2016 15:19:29 -0800 Subject: mm, procfs: breakdown RSS for anon, shmem and file in /proc/pid/status There are several shortcomings with the accounting of shared memory (SysV shm, shared anonymous mapping, mapping of a tmpfs file). The values in /proc//status and <...>/statm don't allow to distinguish between shmem memory and a shared mapping to a regular file, even though theirs implication on memory usage are quite different: during reclaim, file mapping can be dropped or written back on disk, while shmem needs a place in swap. Also, to distinguish the memory occupied by anonymous and file mappings, one has to read the /proc/pid/statm file, which has a field for the file mappings (again, including shmem) and total memory occupied by these mappings (i.e. equivalent to VmRSS in the <...>/status file. Getting the value for anonymous mappings only is thus not exactly user-friendly (the statm file is intended to be rather efficiently machine-readable). To address both of these shortcomings, this patch adds a breakdown of VmRSS in /proc//status via new fields RssAnon, RssFile and RssShmem, making use of the previous preparatory patch. These fields tell the user the memory occupied by private anonymous pages, mapped regular files and shmem, respectively. Other existing fields in /status and /statm files are left without change. The /statm file can be extended in the future, if there's a need for that. Example (part of) /proc/pid/status output including the new Rss* fields: VmPeak: 2001008 kB VmSize: 2001004 kB VmLck: 0 kB VmPin: 0 kB VmHWM: 5108 kB VmRSS: 5108 kB RssAnon: 92 kB RssFile: 1324 kB RssShmem: 3692 kB VmData: 192 kB VmStk: 136 kB VmExe: 4 kB VmLib: 1784 kB VmPTE: 3928 kB VmPMD: 20 kB VmSwap: 0 kB HugetlbPages: 0 kB [vbabka@suse.cz: forward-porting, tweak changelog] Signed-off-by: Jerome Marchand Signed-off-by: Vlastimil Babka Acked-by: Konstantin Khlebnikov Acked-by: Michal Hocko Acked-by: Hugh Dickins Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/filesystems/proc.txt | 13 +++++++++++-- fs/proc/task_mmu.c | 14 ++++++++++++-- 2 files changed, 23 insertions(+), 4 deletions(-) (limited to 'Documentation/filesystems') diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt index fdeb5b33349f..ffcd49589ab5 100644 --- a/Documentation/filesystems/proc.txt +++ b/Documentation/filesystems/proc.txt @@ -169,6 +169,9 @@ read the file /proc/PID/status: VmLck: 0 kB VmHWM: 476 kB VmRSS: 476 kB + RssAnon: 352 kB + RssFile: 120 kB + RssShmem: 4 kB VmData: 156 kB VmStk: 88 kB VmExe: 68 kB @@ -231,7 +234,12 @@ Table 1-2: Contents of the status files (as of 4.1) VmSize total program size VmLck locked memory size VmHWM peak resident set size ("high water mark") - VmRSS size of memory portions + VmRSS size of memory portions. It contains the three + following parts (VmRSS = RssAnon + RssFile + RssShmem) + RssAnon size of resident anonymous memory + RssFile size of resident file mappings + RssShmem size of resident shmem memory (includes SysV shm, + mapping of tmpfs and shared anonymous mappings) VmData size of data, stack, and text segments VmStk size of data, stack, and text segments VmExe size of text segment @@ -266,7 +274,8 @@ Table 1-3: Contents of the statm files (as of 2.6.8-rc3) Field Content size total program size (pages) (same as VmSize in status) resident size of memory portions (pages) (same as VmRSS in status) - shared number of pages that are shared (i.e. backed by a file) + shared number of pages that are shared (i.e. backed by a file, same + as RssFile+RssShmem in status) trs number of pages that are 'code' (not including libs; broken, includes data segment) lrs number of pages of library (always 0 on 2.6) diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c index 45eb24145978..18a30aedfa5d 100644 --- a/fs/proc/task_mmu.c +++ b/fs/proc/task_mmu.c @@ -23,9 +23,13 @@ void task_mem(struct seq_file *m, struct mm_struct *mm) { - unsigned long data, text, lib, swap, ptes, pmds; + unsigned long data, text, lib, swap, ptes, pmds, anon, file, shmem; unsigned long hiwater_vm, total_vm, hiwater_rss, total_rss; + anon = get_mm_counter(mm, MM_ANONPAGES); + file = get_mm_counter(mm, MM_FILEPAGES); + shmem = get_mm_counter(mm, MM_SHMEMPAGES); + /* * Note: to minimize their overhead, mm maintains hiwater_vm and * hiwater_rss only when about to *lower* total_vm or rss. Any @@ -36,7 +40,7 @@ void task_mem(struct seq_file *m, struct mm_struct *mm) hiwater_vm = total_vm = mm->total_vm; if (hiwater_vm < mm->hiwater_vm) hiwater_vm = mm->hiwater_vm; - hiwater_rss = total_rss = get_mm_rss(mm); + hiwater_rss = total_rss = anon + file + shmem; if (hiwater_rss < mm->hiwater_rss) hiwater_rss = mm->hiwater_rss; @@ -53,6 +57,9 @@ void task_mem(struct seq_file *m, struct mm_struct *mm) "VmPin:\t%8lu kB\n" "VmHWM:\t%8lu kB\n" "VmRSS:\t%8lu kB\n" + "RssAnon:\t%8lu kB\n" + "RssFile:\t%8lu kB\n" + "RssShmem:\t%8lu kB\n" "VmData:\t%8lu kB\n" "VmStk:\t%8lu kB\n" "VmExe:\t%8lu kB\n" @@ -66,6 +73,9 @@ void task_mem(struct seq_file *m, struct mm_struct *mm) mm->pinned_vm << (PAGE_SHIFT-10), hiwater_rss << (PAGE_SHIFT-10), total_rss << (PAGE_SHIFT-10), + anon << (PAGE_SHIFT-10), + file << (PAGE_SHIFT-10), + shmem << (PAGE_SHIFT-10), data << (PAGE_SHIFT-10), mm->stack_vm << (PAGE_SHIFT-10), text, lib, ptes >> 10, -- cgit v1.2.3 From 0bc126d460453736c0e03d9da7ae0e9d4fcf86b3 Mon Sep 17 00:00:00 2001 From: Rodrigo Freire Date: Thu, 14 Jan 2016 15:21:58 -0800 Subject: Documentation/filesystems: describe the shared memory usage/accounting The Shared Memory accounting support is present in Kernel since commit 4b02108ac1b3 ("mm: oom analysis: add shmem vmstat") and in userland free(1) since 2014. This patch updates the Documentation to reflect this change. Signed-off-by: Rodrigo Freire Acked-by: Vlastimil Babka Cc: Hugh Dickins Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/filesystems/proc.txt | 2 ++ Documentation/filesystems/tmpfs.txt | 8 ++++---- 2 files changed, 6 insertions(+), 4 deletions(-) (limited to 'Documentation/filesystems') diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt index ffcd49589ab5..e95aa1c6eadf 100644 --- a/Documentation/filesystems/proc.txt +++ b/Documentation/filesystems/proc.txt @@ -855,6 +855,7 @@ Dirty: 968 kB Writeback: 0 kB AnonPages: 861800 kB Mapped: 280372 kB +Shmem: 644 kB Slab: 284364 kB SReclaimable: 159856 kB SUnreclaim: 124508 kB @@ -911,6 +912,7 @@ MemAvailable: An estimate of how much memory is available for starting new AnonPages: Non-file backed pages mapped into userspace page tables AnonHugePages: Non-file backed huge pages mapped into userspace page tables Mapped: files which have been mmaped, such as libraries + Shmem: Total memory used by shared memory (shmem) and tmpfs Slab: in-kernel data structures cache SReclaimable: Part of Slab, that might be reclaimed, such as caches SUnreclaim: Part of Slab, that cannot be reclaimed on memory pressure diff --git a/Documentation/filesystems/tmpfs.txt b/Documentation/filesystems/tmpfs.txt index 98ef55124158..d392e1505f17 100644 --- a/Documentation/filesystems/tmpfs.txt +++ b/Documentation/filesystems/tmpfs.txt @@ -17,10 +17,10 @@ RAM, where you have to create an ordinary filesystem on top. Ramdisks cannot swap and you do not have the possibility to resize them. Since tmpfs lives completely in the page cache and on swap, all tmpfs -pages currently in memory will show up as cached. It will not show up -as shared or something like that. Further on you can check the actual -RAM+swap use of a tmpfs instance with df(1) and du(1). - +pages will be shown as "Shmem" in /proc/meminfo and "Shared" in +free(1). Notice that these counters also include shared memory +(shmem, see ipcs(1)). The most reliable way to get the count is +using df(1) and du(1). tmpfs has the following uses: -- cgit v1.2.3 From 28016128d37a46d89ac5d9a450709284148989d6 Mon Sep 17 00:00:00 2001 From: Namjae Jeon Date: Wed, 20 Jan 2016 14:59:49 -0800 Subject: Documentation/filesystems/vfat.txt: update the limitation for fat fallocate Update the limitation for fat fallocate. Signed-off-by: Namjae Jeon Signed-off-by: Amit Sahrawat Cc: OGAWA Hirofumi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/filesystems/vfat.txt | 10 ++++++++++ 1 file changed, 10 insertions(+) (limited to 'Documentation/filesystems') diff --git a/Documentation/filesystems/vfat.txt b/Documentation/filesystems/vfat.txt index ce1126aceed8..223c32171dcc 100644 --- a/Documentation/filesystems/vfat.txt +++ b/Documentation/filesystems/vfat.txt @@ -180,6 +180,16 @@ dos1xfloppy -- If set, use a fallback default BIOS Parameter Block : 0,1,yes,no,true,false +LIMITATION +--------------------------------------------------------------------- +* The fallocated region of file is discarded at umount/evict time + when using fallocate with FALLOC_FL_KEEP_SIZE. + So, User should assume that fallocated region can be discarded at + last close if there is memory pressure resulting in eviction of + the inode from the memory. As a result, for any dependency on + the fallocated region, user should make sure to recheck fallocate + after reopening the file. + TODO ---------------------------------------------------------------------- * Need to get rid of the raw scanning stuff. Instead, always use -- cgit v1.2.3