diff options
| author | Christoph Hellwig <hch@lst.de> | 2005-06-23 00:09:49 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-06-23 09:45:26 -0700 |
| commit | c663e5d80ebec426916ad2aa5400c7ec99aa572e (patch) | |
| tree | 463dd4600525e536ed00579fa30bab9708c53824 /fs/namei.c | |
| parent | 70f09f1fdf38cd7fca39913978d18cf998ab2c80 (diff) | |
[PATCH] add some comments to lookup_create()
In a duplicate of lookup_create in the af_unix code Al commented what's
going on nicely, so let's bring that over to lookup_create before the copy
is going away (I'll send a patch soon)
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'fs/namei.c')
| -rw-r--r-- | fs/namei.c | 20 |
1 files changed, 18 insertions, 2 deletions
diff --git a/fs/namei.c b/fs/namei.c index a7f7f44119b..fa8df81ce8c 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -1577,19 +1577,35 @@ do_link: * * Simple function to lookup and return a dentry and create it * if it doesn't exist. Is SMP-safe. + * + * Returns with nd->dentry->d_inode->i_sem locked. */ struct dentry *lookup_create(struct nameidata *nd, int is_dir) { - struct dentry *dentry; + struct dentry *dentry = ERR_PTR(-EEXIST); down(&nd->dentry->d_inode->i_sem); - dentry = ERR_PTR(-EEXIST); + /* + * Yucky last component or no last component at all? + * (foo/., foo/.., /////) + */ if (nd->last_type != LAST_NORM) goto fail; nd->flags &= ~LOOKUP_PARENT; + + /* + * Do the final lookup. + */ dentry = lookup_hash(&nd->last, nd->dentry); if (IS_ERR(dentry)) goto fail; + + /* + * Special case - lookup gave negative, but... we had foo/bar/ + * From the vfs_mknod() POV we just have a negative dentry - + * all is fine. Let's be bastards - you had / on the end, you've + * been asking for (non-existent) directory. -ENOENT for you. + */ if (!is_dir && nd->last.name[nd->last.len] && !dentry->d_inode) goto enoent; return dentry; |