diff options
Diffstat (limited to 'fs/fat/inode.c')
| -rw-r--r-- | fs/fat/inode.c | 57 |
1 files changed, 56 insertions, 1 deletions
diff --git a/fs/fat/inode.c b/fs/fat/inode.c index 854b578f6695..ba9831d9f648 100644 --- a/fs/fat/inode.c +++ b/fs/fat/inode.c @@ -54,6 +54,25 @@ 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) @@ -68,8 +87,11 @@ 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) @@ -93,6 +115,7 @@ 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) @@ -206,6 +229,13 @@ static ssize_t fat_direct_IO(int rw, struct kiocb *iocb, loff_t size = offset + iov_length(iov, nr_segs); 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; } /* @@ -226,7 +256,10 @@ static sector_t _fat_bmap(struct address_space *mapping, sector_t block) /* fat_get_cluster() assumes the requested blocknr isn't truncated. */ down_read(&MSDOS_I(mapping->host)->truncate_lock); + /* To get block number beyond file size in fallocated region */ + atomic_set(&MSDOS_I(mapping->host)->beyond_isize, 1); blocknr = generic_block_bmap(mapping, block, fat_get_block); + atomic_set(&MSDOS_I(mapping->host)->beyond_isize, 0); up_read(&MSDOS_I(mapping->host)->truncate_lock); return blocknr; @@ -408,6 +441,7 @@ int fat_fill_inode(struct inode *inode, struct msdos_dir_entry *de) if (error < 0) return error; MSDOS_I(inode)->mmu_private = inode->i_size; + MSDOS_I(inode)->i_disksize = inode->i_size; set_nlink(inode, fat_subdirs(inode)); } else { /* not a directory */ @@ -423,6 +457,7 @@ int fat_fill_inode(struct inode *inode, struct msdos_dir_entry *de) inode->i_fop = &fat_file_operations; inode->i_mapping->a_ops = &fat_aops; MSDOS_I(inode)->mmu_private = inode->i_size; + MSDOS_I(inode)->i_disksize = inode->i_size; } if (de->attr & ATTR_SYS) { if (sbi->options.sys_immutable) @@ -494,6 +529,25 @@ static void fat_evict_inode(struct inode *inode) 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)->mmu_private < MSDOS_I(inode)->i_disksize) { + 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 + * synchrnously to avoid any corruption on the next + * access to the cluster chain for the file. + */ + err = fat_sync_inode(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); @@ -1223,6 +1277,7 @@ 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; |