diff options
Diffstat (limited to 'fs/fat/inode.c')
-rw-r--r-- | fs/fat/inode.c | 87 |
1 files changed, 83 insertions, 4 deletions
diff --git a/fs/fat/inode.c b/fs/fat/inode.c index 756aead10d96..c3b86c58ad88 100644 --- a/fs/fat/inode.c +++ b/fs/fat/inode.c @@ -116,6 +116,25 @@ static int fat_add_cluster(struct inode *inode) return err; } +static void check_fallocated_region(struct inode *inode, sector_t iblock, + unsigned long *max_blocks, struct buffer_head *bh_result) +{ + struct super_block *sb = inode->i_sb; + sector_t last_block, disk_block; + const unsigned long blocksize = sb->s_blocksize; + const unsigned char blocksize_bits = sb->s_blocksize_bits; + + last_block = (MSDOS_I(inode)->mmu_private + (blocksize - 1)) + >> blocksize_bits; + disk_block = (MSDOS_I(inode)->i_disksize + (blocksize - 1)) + >> blocksize_bits; + if (iblock >= last_block && iblock <= disk_block) { + MSDOS_I(inode)->mmu_private += *max_blocks << blocksize_bits; + set_buffer_new(bh_result); + } + +} + static inline int __fat_get_block(struct inode *inode, sector_t iblock, unsigned long *max_blocks, struct buffer_head *bh_result, int create) @@ -130,8 +149,11 @@ static inline int __fat_get_block(struct inode *inode, sector_t iblock, if (err) return err; if (phys) { - map_bh(bh_result, sb, phys); *max_blocks = min(mapped_blocks, *max_blocks); + if (create) + check_fallocated_region(inode, iblock, max_blocks, + bh_result); + map_bh(bh_result, sb, phys); return 0; } if (!create) @@ -155,6 +177,7 @@ static inline int __fat_get_block(struct inode *inode, sector_t iblock, *max_blocks = min(mapped_blocks, *max_blocks); MSDOS_I(inode)->mmu_private += *max_blocks << sb->s_blocksize_bits; + MSDOS_I(inode)->i_disksize = MSDOS_I(inode)->mmu_private; err = fat_bmap(inode, iblock, &phys, &mapped_blocks, create); if (err) @@ -269,6 +292,13 @@ static ssize_t fat_direct_IO(int rw, struct kiocb *iocb, loff_t size = offset + count; if (MSDOS_I(inode)->mmu_private < size) return 0; + + /* + * In case of writing in fallocated region, return 0 and + * fallback to buffered write. + */ + if (MSDOS_I(inode)->i_disksize > MSDOS_I(inode)->mmu_private) + return 0; } /* @@ -282,13 +312,36 @@ static ssize_t fat_direct_IO(int rw, struct kiocb *iocb, return ret; } +static int fat_get_block_bmap(struct inode *inode, sector_t iblock, + struct buffer_head *bh_result, int create) +{ + struct super_block *sb = inode->i_sb; + unsigned long max_blocks = bh_result->b_size >> inode->i_blkbits; + int err; + sector_t bmap; + unsigned long mapped_blocks; + + err = fat_bmap2(inode, iblock, &mapped_blocks, bh_result, create, + &bmap); + if (err) + return err; + + if (bmap) { + map_bh(bh_result, sb, bmap); + max_blocks = min(mapped_blocks, max_blocks); + } + + bh_result->b_size = max_blocks << sb->s_blocksize_bits; + return 0; +} + static sector_t _fat_bmap(struct address_space *mapping, sector_t block) { sector_t blocknr; /* fat_get_cluster() assumes the requested blocknr isn't truncated. */ down_read(&MSDOS_I(mapping->host)->truncate_lock); - blocknr = generic_block_bmap(mapping, block, fat_get_block); + blocknr = generic_block_bmap(mapping, block, fat_get_block_bmap); up_read(&MSDOS_I(mapping->host)->truncate_lock); return blocknr; @@ -469,7 +522,6 @@ int fat_fill_inode(struct inode *inode, struct msdos_dir_entry *de) error = fat_calc_dir_size(inode); if (error < 0) return error; - MSDOS_I(inode)->mmu_private = inode->i_size; set_nlink(inode, fat_subdirs(inode)); } else { /* not a directory */ @@ -484,8 +536,12 @@ int fat_fill_inode(struct inode *inode, struct msdos_dir_entry *de) inode->i_op = &fat_file_inode_operations; inode->i_fop = &fat_file_operations; inode->i_mapping->a_ops = &fat_aops; - MSDOS_I(inode)->mmu_private = inode->i_size; } + + MSDOS_I(inode)->mmu_private = inode->i_size; + MSDOS_I(inode)->i_disksize = round_up(inode->i_size, + inode->i_sb->s_blocksize); + if (de->attr & ATTR_SYS) { if (sbi->options.sys_immutable) inode->i_flags |= S_IMMUTABLE; @@ -550,12 +606,34 @@ out: EXPORT_SYMBOL_GPL(fat_build_inode); +static int __fat_write_inode(struct inode *inode, int wait); static void fat_evict_inode(struct inode *inode) { truncate_inode_pages_final(&inode->i_data); if (!inode->i_nlink) { inode->i_size = 0; fat_truncate_blocks(inode, 0); + } else { + /* Release unwritten fallocated blocks on inode eviction. */ + if (MSDOS_I(inode)->i_disksize > + round_up(MSDOS_I(inode)->mmu_private, + inode->i_sb->s_blocksize)) { + int err; + fat_truncate_blocks(inode, MSDOS_I(inode)->mmu_private); + /* Fallocate results in updating the i_start/iogstart + * for the zero byte file. So, make it return to + * original state during evict and commit it to avoid + * any corruption on the next access to the cluster + * chain for the file. + */ + err = __fat_write_inode(inode, inode_needs_sync(inode)); + if (err) { + fat_msg(inode->i_sb, KERN_WARNING, "Failed to " + "update on disk inode for unused fallocated " + "blocks, inode could be corrupted. Please run " + "fsck"); + } + } } invalidate_inode_buffers(inode); clear_inode(inode); @@ -1293,6 +1371,7 @@ static int fat_read_root(struct inode *inode) & ~((loff_t)sbi->cluster_size - 1)) >> 9; MSDOS_I(inode)->i_logstart = 0; MSDOS_I(inode)->mmu_private = inode->i_size; + MSDOS_I(inode)->i_disksize = inode->i_size; fat_save_attrs(inode, ATTR_DIR); inode->i_mtime.tv_sec = inode->i_atime.tv_sec = inode->i_ctime.tv_sec = 0; |