From 4e29d50a28c267bd1d1731a9fb8f773663d93e23 Mon Sep 17 00:00:00 2001 From: Artem Bityutskiy Date: Mon, 5 Jul 2010 15:15:01 +0300 Subject: [PATCH] BFS: clean up the superblock usage BFS is a very simple FS and its superblocks contains only static information and is never changed. However, the BFS code for some misterious reasons marked its buffer head as dirty from time to time, but nothing in that buffer was ever changed. This patch removes all the BFS superblock manipulation, simply because it is not needed. It removes: 1. The si_sbh filed from 'struct bfs_sb_info' because it is not needed. We only need to read the SB once on mount to get the start of data blocks and the FS size. After this, we can forget about the SB. 2. All instances of 'mark_buffer_dirty(sbh)' for BFS SB because it is never changed. 3. The '->sync_fs()' method because there is nothing to sync (inodes are synched by VFS). 4. The '->write_super()' method, again, because the SB is never changed. Tested-by: Artem Bityutskiy Signed-off-by: Artem Bityutskiy Signed-off-by: Al Viro --- fs/bfs/bfs.h | 1 - fs/bfs/file.c | 3 --- fs/bfs/inode.c | 46 +++++++--------------------------------------- 3 files changed, 7 insertions(+), 43 deletions(-) diff --git a/fs/bfs/bfs.h b/fs/bfs/bfs.h index 7109e451abf7..f7f87e233dd9 100644 --- a/fs/bfs/bfs.h +++ b/fs/bfs/bfs.h @@ -17,7 +17,6 @@ struct bfs_sb_info { unsigned long si_lf_eblk; unsigned long si_lasti; unsigned long *si_imap; - struct buffer_head *si_sbh; /* buffer header w/superblock */ struct mutex bfs_lock; }; diff --git a/fs/bfs/file.c b/fs/bfs/file.c index 8fc2e9c9739d..eb67edd0f8ea 100644 --- a/fs/bfs/file.c +++ b/fs/bfs/file.c @@ -70,7 +70,6 @@ static int bfs_get_block(struct inode *inode, sector_t block, struct super_block *sb = inode->i_sb; struct bfs_sb_info *info = BFS_SB(sb); struct bfs_inode_info *bi = BFS_I(inode); - struct buffer_head *sbh = info->si_sbh; phys = bi->i_sblock + block; if (!create) { @@ -112,7 +111,6 @@ static int bfs_get_block(struct inode *inode, sector_t block, info->si_freeb -= phys - bi->i_eblock; info->si_lf_eblk = bi->i_eblock = phys; mark_inode_dirty(inode); - mark_buffer_dirty(sbh); err = 0; goto out; } @@ -147,7 +145,6 @@ static int bfs_get_block(struct inode *inode, sector_t block, */ info->si_freeb -= bi->i_eblock - bi->i_sblock + 1 - inode->i_blocks; mark_inode_dirty(inode); - mark_buffer_dirty(sbh); map_bh(bh_result, sb, phys); out: mutex_unlock(&info->bfs_lock); diff --git a/fs/bfs/inode.c b/fs/bfs/inode.c index 0499822b1568..c4daf0f5fc02 100644 --- a/fs/bfs/inode.c +++ b/fs/bfs/inode.c @@ -31,7 +31,6 @@ MODULE_LICENSE("GPL"); #define dprintf(x...) #endif -static void bfs_write_super(struct super_block *s); void dump_imap(const char *prefix, struct super_block *s); struct inode *bfs_iget(struct super_block *sb, unsigned long ino) @@ -204,33 +203,11 @@ static void bfs_evict_inode(struct inode *inode) * "last block of the last file" even if there is no * real file there, saves us 1 gap. */ - if (info->si_lf_eblk == bi->i_eblock) { + if (info->si_lf_eblk == bi->i_eblock) info->si_lf_eblk = bi->i_sblock - 1; - mark_buffer_dirty(info->si_sbh); - } mutex_unlock(&info->bfs_lock); } -static int bfs_sync_fs(struct super_block *sb, int wait) -{ - struct bfs_sb_info *info = BFS_SB(sb); - - mutex_lock(&info->bfs_lock); - mark_buffer_dirty(info->si_sbh); - sb->s_dirt = 0; - mutex_unlock(&info->bfs_lock); - - return 0; -} - -static void bfs_write_super(struct super_block *sb) -{ - if (!(sb->s_flags & MS_RDONLY)) - bfs_sync_fs(sb, 1); - else - sb->s_dirt = 0; -} - static void bfs_put_super(struct super_block *s) { struct bfs_sb_info *info = BFS_SB(s); @@ -240,10 +217,6 @@ static void bfs_put_super(struct super_block *s) lock_kernel(); - if (s->s_dirt) - bfs_write_super(s); - - brelse(info->si_sbh); mutex_destroy(&info->bfs_lock); kfree(info->si_imap); kfree(info); @@ -315,8 +288,6 @@ static const struct super_operations bfs_sops = { .write_inode = bfs_write_inode, .evict_inode = bfs_evict_inode, .put_super = bfs_put_super, - .write_super = bfs_write_super, - .sync_fs = bfs_sync_fs, .statfs = bfs_statfs, }; @@ -343,7 +314,7 @@ void dump_imap(const char *prefix, struct super_block *s) static int bfs_fill_super(struct super_block *s, void *data, int silent) { - struct buffer_head *bh; + struct buffer_head *bh, *sbh; struct bfs_super_block *bfs_sb; struct inode *inode; unsigned i, imap_len; @@ -359,10 +330,10 @@ static int bfs_fill_super(struct super_block *s, void *data, int silent) sb_set_blocksize(s, BFS_BSIZE); - info->si_sbh = sb_bread(s, 0); - if (!info->si_sbh) + sbh = sb_bread(s, 0); + if (!sbh) goto out; - bfs_sb = (struct bfs_super_block *)info->si_sbh->b_data; + bfs_sb = (struct bfs_super_block *)sbh->b_data; if (le32_to_cpu(bfs_sb->s_magic) != BFS_MAGIC) { if (!silent) printf("No BFS filesystem on %s (magic=%08x)\n", @@ -466,10 +437,7 @@ static int bfs_fill_super(struct super_block *s, void *data, int silent) info->si_lf_eblk = eblock; } brelse(bh); - if (!(s->s_flags & MS_RDONLY)) { - mark_buffer_dirty(info->si_sbh); - s->s_dirt = 1; - } + brelse(sbh); dump_imap("read_super", s); return 0; @@ -479,7 +447,7 @@ static int bfs_fill_super(struct super_block *s, void *data, int silent) out2: kfree(info->si_imap); out1: - brelse(info->si_sbh); + brelse(sbh); out: mutex_destroy(&info->bfs_lock); kfree(info);