From 3d23985d6cfa7908e46fd0c62a2ee84faffe4d8b Mon Sep 17 00:00:00 2001 From: Al Viro Date: Sat, 18 Dec 2010 10:44:00 -0500 Subject: [PATCH] switch fat to ->s_d_op, close exportfs races there don't bother with lock_super() in fat_fill_super() callers, while we are at it - there won't be any concurrency anyway. Signed-off-by: Al Viro --- fs/fat/fat.h | 3 ++- fs/fat/inode.c | 13 +++++-------- fs/fat/namei_msdos.c | 27 +++++++++------------------ fs/fat/namei_vfat.c | 27 +++++++++------------------ 4 files changed, 25 insertions(+), 45 deletions(-) diff --git a/fs/fat/fat.h b/fs/fat/fat.h index d75a77f85c28..f50408901f7e 100644 --- a/fs/fat/fat.h +++ b/fs/fat/fat.h @@ -319,7 +319,8 @@ extern struct inode *fat_build_inode(struct super_block *sb, struct msdos_dir_entry *de, loff_t i_pos); extern int fat_sync_inode(struct inode *inode); extern int fat_fill_super(struct super_block *sb, void *data, int silent, - const struct inode_operations *fs_dir_inode_ops, int isvfat); + const struct inode_operations *fs_dir_inode_ops, + int isvfat, void (*setup)(struct super_block *)); extern int fat_flush_inodes(struct super_block *sb, struct inode *i1, struct inode *i2); diff --git a/fs/fat/inode.c b/fs/fat/inode.c index 206351af7c58..86753fe10bd1 100644 --- a/fs/fat/inode.c +++ b/fs/fat/inode.c @@ -703,7 +703,6 @@ static struct dentry *fat_fh_to_dentry(struct super_block *sb, struct fid *fid, int fh_len, int fh_type) { struct inode *inode = NULL; - struct dentry *result; u32 *fh = fid->raw; if (fh_len < 5 || fh_type != 3) @@ -748,10 +747,7 @@ static struct dentry *fat_fh_to_dentry(struct super_block *sb, * the fat_iget lookup again. If that fails, then we are totally out * of luck. But all that is for another day */ - result = d_obtain_alias(inode); - if (!IS_ERR(result)) - d_set_d_op(result, sb->s_root->d_op); - return result; + return d_obtain_alias(inode); } static int @@ -799,8 +795,6 @@ static struct dentry *fat_get_parent(struct dentry *child) brelse(bh); parent = d_obtain_alias(inode); - if (!IS_ERR(parent)) - d_set_d_op(parent, sb->s_root->d_op); out: unlock_super(sb); @@ -1244,7 +1238,8 @@ static int fat_read_root(struct inode *inode) * Read the super block of an MS-DOS FS. */ int fat_fill_super(struct super_block *sb, void *data, int silent, - const struct inode_operations *fs_dir_inode_ops, int isvfat) + const struct inode_operations *fs_dir_inode_ops, int isvfat, + void (*setup)(struct super_block *)) { struct inode *root_inode = NULL, *fat_inode = NULL; struct buffer_head *bh; @@ -1280,6 +1275,8 @@ int fat_fill_super(struct super_block *sb, void *data, int silent, if (error) goto out_fail; + setup(sb); /* flavour-specific stuff that needs options */ + error = -EIO; sb_min_blocksize(sb, 512); bh = sb_bread(sb, 0); diff --git a/fs/fat/namei_msdos.c b/fs/fat/namei_msdos.c index 35ffe43afa4b..711499040eb6 100644 --- a/fs/fat/namei_msdos.c +++ b/fs/fat/namei_msdos.c @@ -227,11 +227,7 @@ static struct dentry *msdos_lookup(struct inode *dir, struct dentry *dentry, } out: unlock_super(sb); - d_set_d_op(dentry, &msdos_dentry_operations); - dentry = d_splice_alias(inode, dentry); - if (dentry) - d_set_d_op(dentry, &msdos_dentry_operations); - return dentry; + return d_splice_alias(inode, dentry); error: unlock_super(sb); @@ -661,21 +657,16 @@ static const struct inode_operations msdos_dir_inode_operations = { .getattr = fat_getattr, }; -static int msdos_fill_super(struct super_block *sb, void *data, int silent) +static void setup(struct super_block *sb) { - int res; - - lock_super(sb); - res = fat_fill_super(sb, data, silent, &msdos_dir_inode_operations, 0); - if (res) { - unlock_super(sb); - return res; - } - + sb->s_d_op = &msdos_dentry_operations; sb->s_flags |= MS_NOATIME; - d_set_d_op(sb->s_root, &msdos_dentry_operations); - unlock_super(sb); - return 0; +} + +static int msdos_fill_super(struct super_block *sb, void *data, int silent) +{ + return fat_fill_super(sb, data, silent, &msdos_dir_inode_operations, + 0, setup); } static struct dentry *msdos_mount(struct file_system_type *fs_type, diff --git a/fs/fat/namei_vfat.c b/fs/fat/namei_vfat.c index e3ffc5e12332..f88f752babd9 100644 --- a/fs/fat/namei_vfat.c +++ b/fs/fat/namei_vfat.c @@ -772,13 +772,10 @@ static struct dentry *vfat_lookup(struct inode *dir, struct dentry *dentry, out: unlock_super(sb); - d_set_d_op(dentry, sb->s_root->d_op); dentry->d_time = dentry->d_parent->d_inode->i_version; dentry = d_splice_alias(inode, dentry); - if (dentry) { - d_set_d_op(dentry, sb->s_root->d_op); + if (dentry) dentry->d_time = dentry->d_parent->d_inode->i_version; - } return dentry; error: @@ -1066,24 +1063,18 @@ static const struct inode_operations vfat_dir_inode_operations = { .getattr = fat_getattr, }; -static int vfat_fill_super(struct super_block *sb, void *data, int silent) +static void setup(struct super_block *sb) { - int res; - - lock_super(sb); - res = fat_fill_super(sb, data, silent, &vfat_dir_inode_operations, 1); - if (res) { - unlock_super(sb); - return res; - } - if (MSDOS_SB(sb)->options.name_check != 's') - d_set_d_op(sb->s_root, &vfat_ci_dentry_ops); + sb->s_d_op = &vfat_ci_dentry_ops; else - d_set_d_op(sb->s_root, &vfat_dentry_ops); + sb->s_d_op = &vfat_dentry_ops; +} - unlock_super(sb); - return 0; +static int vfat_fill_super(struct super_block *sb, void *data, int silent) +{ + return fat_fill_super(sb, data, silent, &vfat_dir_inode_operations, + 1, setup); } static struct dentry *vfat_mount(struct file_system_type *fs_type, -- 2.39.2