diff options
Diffstat (limited to 'fs/fat/inode.c')
| -rw-r--r-- | fs/fat/inode.c | 79 |
1 files changed, 75 insertions, 4 deletions
diff --git a/fs/fat/inode.c b/fs/fat/inode.c index 756aead10d96..f36279688a75 100644 --- a/fs/fat/inode.c +++ b/fs/fat/inode.c @@ -104,6 +104,7 @@ static struct fat_floppy_defaults { static int fat_add_cluster(struct inode *inode) { int err, cluster; + struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb); err = fat_alloc_clusters(inode, &cluster, 1); if (err) @@ -113,9 +114,20 @@ static int fat_add_cluster(struct inode *inode) err = fat_chain_add(inode, cluster, 1); if (err) fat_free_clusters(inode, cluster); + else + MSDOS_I(inode)->i_disksize += sbi->cluster_size; + return err; } +static inline int check_fallocated_region(struct inode *inode, sector_t iblock) +{ + struct super_block *sb = inode->i_sb; + sector_t last_disk_block = MSDOS_I(inode)->i_disksize >> + sb->s_blocksize_bits; + return iblock < last_disk_block; +} + static inline int __fat_get_block(struct inode *inode, sector_t iblock, unsigned long *max_blocks, struct buffer_head *bh_result, int create) @@ -144,7 +156,7 @@ static inline int __fat_get_block(struct inode *inode, sector_t iblock, } offset = (unsigned long)iblock & (sbi->sec_per_clus - 1); - if (!offset) { + if (!offset && !check_fallocated_region(inode, iblock)) { /* TODO: multiple cluster allocation would be desirable. */ err = fat_add_cluster(inode); if (err) @@ -282,13 +294,46 @@ 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, last_block; + unsigned long mapped_blocks; + const unsigned long blocksize = sb->s_blocksize; + const unsigned char blocksize_bits = sb->s_blocksize_bits; + + BUG_ON(create != 0); + + last_block = (MSDOS_I(inode)->i_disksize + (blocksize - 1)) + >> blocksize_bits; + + if (iblock >= last_block) + return 0; + + err = fat_get_mapped_cluster(inode, iblock, last_block, &mapped_blocks, + &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 +514,6 @@ 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 +528,11 @@ 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, sbi->cluster_size); + if (de->attr & ATTR_SYS) { if (sbi->options.sys_immutable) inode->i_flags |= S_IMMUTABLE; @@ -550,12 +597,35 @@ 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 +1363,7 @@ 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 = round_up(inode->i_size, sbi->cluster_size); fat_save_attrs(inode, ATTR_DIR); inode->i_mtime.tv_sec = inode->i_atime.tv_sec = inode->i_ctime.tv_sec = 0; |