bfs: kill BKL

Replace the BKL-based locking scheme used in the bfs driver by a private
filesystem-wide mutex.

Signed-off-by: Dmitri Vorobiev <dmitri.vorobiev@movial.fi>
Cc: Tigran Aivazian <tigran_aivazian@symantec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/fs/bfs/bfs.h b/fs/bfs/bfs.h
index d1a6cd1..7109e45 100644 (file)
--- a/fs/bfs/bfs.h
+++ b/fs/bfs/bfs.h
@@ -18,6 +18,7 @@ struct bfs_sb_info {
        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/dir.c b/fs/bfs/dir.c
index 034950c..87ee5cc 100644 (file)
--- a/fs/bfs/dir.c
+++ b/fs/bfs/dir.c
@@ -32,16 +32,17 @@ static int bfs_readdir(struct file *f, void *dirent, filldir_t filldir)
        struct inode *dir = f->f_path.dentry->d_inode;
        struct buffer_head *bh;
        struct bfs_dirent *de;
+       struct bfs_sb_info *info = BFS_SB(dir->i_sb);
        unsigned int offset;
        int block;
 
-       lock_kernel();
+       mutex_lock(&info->bfs_lock);
 
        if (f->f_pos & (BFS_DIRENT_SIZE - 1)) {
                printf("Bad f_pos=%08lx for %s:%08lx\n",
                                        (unsigned long)f->f_pos,
                                        dir->i_sb->s_id, dir->i_ino);
-               unlock_kernel();
+               mutex_unlock(&info->bfs_lock);
                return -EBADF;
        }
 
@@ -61,7 +62,7 @@ static int bfs_readdir(struct file *f, void *dirent, filldir_t filldir)
                                                le16_to_cpu(de->ino),
                                                DT_UNKNOWN) < 0) {
                                        brelse(bh);
-                                       unlock_kernel();
+                                       mutex_unlock(&info->bfs_lock);
                                        return 0;
                                }
                        }
@@ -71,7 +72,7 @@ static int bfs_readdir(struct file *f, void *dirent, filldir_t filldir)
                brelse(bh);
        }
 
-       unlock_kernel();
+       mutex_unlock(&info->bfs_lock);
        return 0;       
 }
 
@@ -95,10 +96,10 @@ static int bfs_create(struct inode *dir, struct dentry *dentry, int mode,
        inode = new_inode(s);
        if (!inode)
                return -ENOSPC;
-       lock_kernel();
+       mutex_lock(&info->bfs_lock);
        ino = find_first_zero_bit(info->si_imap, info->si_lasti);
        if (ino > info->si_lasti) {
-               unlock_kernel();
+               mutex_unlock(&info->bfs_lock);
                iput(inode);
                return -ENOSPC;
        }
@@ -125,10 +126,10 @@ static int bfs_create(struct inode *dir, struct dentry *dentry, int mode,
        if (err) {
                inode_dec_link_count(inode);
                iput(inode);
-               unlock_kernel();
+               mutex_unlock(&info->bfs_lock);
                return err;
        }
-       unlock_kernel();
+       mutex_unlock(&info->bfs_lock);
        d_instantiate(dentry, inode);
        return 0;
 }
@@ -139,22 +140,23 @@ static struct dentry *bfs_lookup(struct inode *dir, struct dentry *dentry,
        struct inode *inode = NULL;
        struct buffer_head *bh;
        struct bfs_dirent *de;
+       struct bfs_sb_info *info = BFS_SB(dir->i_sb);
 
        if (dentry->d_name.len > BFS_NAMELEN)
                return ERR_PTR(-ENAMETOOLONG);
 
-       lock_kernel();
+       mutex_lock(&info->bfs_lock);
        bh = bfs_find_entry(dir, dentry->d_name.name, dentry->d_name.len, &de);
        if (bh) {
                unsigned long ino = (unsigned long)le16_to_cpu(de->ino);
                brelse(bh);
                inode = bfs_iget(dir->i_sb, ino);
                if (IS_ERR(inode)) {
-                       unlock_kernel();
+                       mutex_unlock(&info->bfs_lock);
                        return ERR_CAST(inode);
                }
        }
-       unlock_kernel();
+       mutex_unlock(&info->bfs_lock);
        d_add(dentry, inode);
        return NULL;
 }
@@ -163,13 +165,14 @@ static int bfs_link(struct dentry *old, struct inode *dir,
                                                struct dentry *new)
 {
        struct inode *inode = old->d_inode;
+       struct bfs_sb_info *info = BFS_SB(inode->i_sb);
        int err;
 
-       lock_kernel();
+       mutex_lock(&info->bfs_lock);
        err = bfs_add_entry(dir, new->d_name.name, new->d_name.len,
                                                        inode->i_ino);
        if (err) {
-               unlock_kernel();
+               mutex_unlock(&info->bfs_lock);
                return err;
        }
        inc_nlink(inode);
@@ -177,19 +180,19 @@ static int bfs_link(struct dentry *old, struct inode *dir,
        mark_inode_dirty(inode);
        atomic_inc(&inode->i_count);
        d_instantiate(new, inode);
-       unlock_kernel();
+       mutex_unlock(&info->bfs_lock);
        return 0;
 }
 
 static int bfs_unlink(struct inode *dir, struct dentry *dentry)
 {
        int error = -ENOENT;
-       struct inode *inode;
+       struct inode *inode = dentry->d_inode;
        struct buffer_head *bh;
        struct bfs_dirent *de;
+       struct bfs_sb_info *info = BFS_SB(inode->i_sb);
 
-       inode = dentry->d_inode;
-       lock_kernel();
+       mutex_lock(&info->bfs_lock);
        bh = bfs_find_entry(dir, dentry->d_name.name, dentry->d_name.len, &de);
        if (!bh || (le16_to_cpu(de->ino) != inode->i_ino))
                goto out_brelse;
@@ -210,7 +213,7 @@ static int bfs_unlink(struct inode *dir, struct dentry *dentry)
 
 out_brelse:
        brelse(bh);
-       unlock_kernel();
+       mutex_unlock(&info->bfs_lock);
        return error;
 }
 
@@ -220,6 +223,7 @@ static int bfs_rename(struct inode *old_dir, struct dentry *old_dentry,
        struct inode *old_inode, *new_inode;
        struct buffer_head *old_bh, *new_bh;
        struct bfs_dirent *old_de, *new_de;
+       struct bfs_sb_info *info;
        int error = -ENOENT;
 
        old_bh = new_bh = NULL;
@@ -227,7 +231,9 @@ static int bfs_rename(struct inode *old_dir, struct dentry *old_dentry,
        if (S_ISDIR(old_inode->i_mode))
                return -EINVAL;
 
-       lock_kernel();
+       info = BFS_SB(old_inode->i_sb);
+
+       mutex_lock(&info->bfs_lock);
        old_bh = bfs_find_entry(old_dir, 
                                old_dentry->d_name.name, 
                                old_dentry->d_name.len, &old_de);
@@ -264,7 +270,7 @@ static int bfs_rename(struct inode *old_dir, struct dentry *old_dentry,
        error = 0;
 
 end_rename:
-       unlock_kernel();
+       mutex_unlock(&info->bfs_lock);
        brelse(old_bh);
        brelse(new_bh);
        return error;

diff --git a/fs/bfs/file.c b/fs/bfs/file.c
index b11e63e..6a02126 100644 (file)
--- a/fs/bfs/file.c
+++ b/fs/bfs/file.c
@@ -99,7 +99,7 @@ static int bfs_get_block(struct inode *inode, sector_t block,
                return -ENOSPC;
 
        /* The rest has to be protected against itself. */
-       lock_kernel();
+       mutex_lock(&info->bfs_lock);
 
        /*
         * If the last data block for this file is the last allocated
@@ -151,7 +151,7 @@ static int bfs_get_block(struct inode *inode, sector_t block,
        mark_buffer_dirty(sbh);
        map_bh(bh_result, sb, phys);
 out:
-       unlock_kernel();
+       mutex_unlock(&info->bfs_lock);
        return err;
 }
 

diff --git a/fs/bfs/inode.c b/fs/bfs/inode.c
index c8b3982..053e690 100644 (file)
--- a/fs/bfs/inode.c
+++ b/fs/bfs/inode.c
@@ -104,6 +104,7 @@ static int bfs_write_inode(struct inode *inode, int unused)
        struct bfs_inode *di;
        struct buffer_head *bh;
        int block, off;
+       struct bfs_sb_info *info = BFS_SB(inode->i_sb);
 
         dprintf("ino=%08x\n", ino);
 
@@ -112,13 +113,13 @@ static int bfs_write_inode(struct inode *inode, int unused)
                return -EIO;
        }
 
-       lock_kernel();
+       mutex_lock(&info->bfs_lock);
        block = (ino - BFS_ROOT_INO) / BFS_INODES_PER_BLOCK + 1;
        bh = sb_bread(inode->i_sb, block);
        if (!bh) {
                printf("Unable to read inode %s:%08x\n",
                                inode->i_sb->s_id, ino);
-               unlock_kernel();
+               mutex_unlock(&info->bfs_lock);
                return -EIO;
        }
 
@@ -145,7 +146,7 @@ static int bfs_write_inode(struct inode *inode, int unused)
 
        mark_buffer_dirty(bh);
        brelse(bh);
-       unlock_kernel();
+       mutex_unlock(&info->bfs_lock);
        return 0;
 }
 
@@ -170,7 +171,7 @@ static void bfs_delete_inode(struct inode *inode)
        
        inode->i_size = 0;
        inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME_SEC;
-       lock_kernel();
+       mutex_lock(&info->bfs_lock);
        mark_inode_dirty(inode);
 
        block = (ino - BFS_ROOT_INO) / BFS_INODES_PER_BLOCK + 1;
@@ -178,7 +179,7 @@ static void bfs_delete_inode(struct inode *inode)
        if (!bh) {
                printf("Unable to read inode %s:%08lx\n",
                                        inode->i_sb->s_id, ino);
-               unlock_kernel();
+               mutex_unlock(&info->bfs_lock);
                return;
        }
        off = (ino - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK;
@@ -204,14 +205,16 @@ static void bfs_delete_inode(struct inode *inode)
                info->si_lf_eblk = bi->i_sblock - 1;
                mark_buffer_dirty(info->si_sbh);
        }
-       unlock_kernel();
+       mutex_unlock(&info->bfs_lock);
        clear_inode(inode);
 }
 
 static void bfs_put_super(struct super_block *s)
 {
        struct bfs_sb_info *info = BFS_SB(s);
+
        brelse(info->si_sbh);
+       mutex_destroy(&info->bfs_lock);
        kfree(info->si_imap);
        kfree(info);
        s->s_fs_info = NULL;
@@ -236,11 +239,13 @@ static int bfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 
 static void bfs_write_super(struct super_block *s)
 {
-       lock_kernel();
+       struct bfs_sb_info *info = BFS_SB(s);
+
+       mutex_lock(&info->bfs_lock);
        if (!(s->s_flags & MS_RDONLY))
-               mark_buffer_dirty(BFS_SB(s)->si_sbh);
+               mark_buffer_dirty(info->si_sbh);
        s->s_dirt = 0;
-       unlock_kernel();
+       mutex_unlock(&info->bfs_lock);
 }
 
 static struct kmem_cache *bfs_inode_cachep;
@@ -409,6 +414,7 @@ static int bfs_fill_super(struct super_block *s, void *data, int silent)
                s->s_dirt = 1;
        } 
        dump_imap("read_super", s);
+       mutex_init(&info->bfs_lock);
        return 0;
 
 out: