From 5ca29607331fe37980dc3b488793ef8b1409b722 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 17 Jul 2007 04:04:29 -0700 Subject: knfsd: exportfs: remove iget abuse When the exportfs interface was added the expectation was that filesystems provide an operation to convert from a file handle to an inode/dentry, but it kept a backwards compat option that still calls into iget. Calling into iget from non-filesystem code is very bad, because it gives too little information to filesystem, and simply crashes if the filesystem doesn't implement the ->read_inode routine. Fortunately there are only two filesystems left using this fallback: efs and jfs. This patch moves a copy of export_iget to each of those to implement the get_dentry method. While this is a temporary increase of lines of code in the kernel it allows for a much cleaner interface and important code restructuring in later patches. [akpm@linux-foundation.org: add jfs_get_inode_flags() declaration] Signed-off-by: Dave Kleikamp Signed-off-by: Christoph Hellwig Signed-off-by: Neil Brown Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/jfs/jfs_inode.h | 1 + fs/jfs/namei.c | 32 ++++++++++++++++++++++++++++++++ fs/jfs/super.c | 1 + 3 files changed, 34 insertions(+) (limited to 'fs/jfs') diff --git a/fs/jfs/jfs_inode.h b/fs/jfs/jfs_inode.h index 2374b595f2e..f0ec72b263f 100644 --- a/fs/jfs/jfs_inode.h +++ b/fs/jfs/jfs_inode.h @@ -32,6 +32,7 @@ extern void jfs_truncate_nolock(struct inode *, loff_t); extern void jfs_free_zero_link(struct inode *); extern struct dentry *jfs_get_parent(struct dentry *dentry); extern void jfs_get_inode_flags(struct jfs_inode_info *); +extern struct dentry *jfs_get_dentry(struct super_block *sb, void *vobjp); extern void jfs_set_inode_flags(struct inode *); extern int jfs_get_block(struct inode *, sector_t, struct buffer_head *, int); diff --git a/fs/jfs/namei.c b/fs/jfs/namei.c index 25161c4121e..932797ba433 100644 --- a/fs/jfs/namei.c +++ b/fs/jfs/namei.c @@ -1477,6 +1477,38 @@ static struct dentry *jfs_lookup(struct inode *dip, struct dentry *dentry, struc return dentry; } +struct dentry *jfs_get_dentry(struct super_block *sb, void *vobjp) +{ + __u32 *objp = vobjp; + unsigned long ino = objp[0]; + __u32 generation = objp[1]; + struct inode *inode; + struct dentry *result; + + if (ino == 0) + return ERR_PTR(-ESTALE); + inode = iget(sb, ino); + if (inode == NULL) + return ERR_PTR(-ENOMEM); + + if (is_bad_inode(inode) || + (generation && inode->i_generation != generation)) { + result = ERR_PTR(-ESTALE); + goto out_iput; + } + + result = d_alloc_anon(inode); + if (!result) { + result = ERR_PTR(-ENOMEM); + goto out_iput; + } + return result; + + out_iput: + iput(inode); + return result; +} + struct dentry *jfs_get_parent(struct dentry *dentry) { struct super_block *sb = dentry->d_inode->i_sb; diff --git a/fs/jfs/super.c b/fs/jfs/super.c index 49b652bd96b..929fceca799 100644 --- a/fs/jfs/super.c +++ b/fs/jfs/super.c @@ -738,6 +738,7 @@ static const struct super_operations jfs_super_operations = { }; static struct export_operations jfs_export_operations = { + .get_dentry = jfs_get_dentry, .get_parent = jfs_get_parent, }; -- cgit v1.2.3