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 <shaggy@linux.vnet.ibm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/jfs/namei.c b/fs/jfs/namei.c
index 25161c4..932797b 100644
--- a/fs/jfs/namei.c
+++ b/fs/jfs/namei.c
@@ -1477,6 +1477,38 @@
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;