diff options
| -rw-r--r-- | fs/dcache.c | 48 |
1 files changed, 18 insertions, 30 deletions
diff --git a/fs/dcache.c b/fs/dcache.c index 07e2d4a44bda..90bbd7e1b116 100644 --- a/fs/dcache.c +++ b/fs/dcache.c @@ -1247,15 +1247,18 @@ struct dentry *d_add_ci(struct dentry *dentry, struct inode *inode, struct dentry *found; struct dentry *new; - /* Does a dentry matching the name exist already? */ + /* + * First check if a dentry matching the name already exists, + * if not go ahead and create it now. + */ found = d_hash_and_lookup(dentry->d_parent, name); - /* If not, create it now and return */ if (!found) { new = d_alloc(dentry->d_parent, name); if (!new) { error = -ENOMEM; goto err_out; } + found = d_splice_alias(inode, new); if (found) { dput(new); @@ -1263,61 +1266,46 @@ struct dentry *d_add_ci(struct dentry *dentry, struct inode *inode, } return new; } - /* Matching dentry exists, check if it is negative. */ + + /* + * If a matching dentry exists, and it's not negative use it. + * + * Decrement the reference count to balance the iget() done + * earlier on. + */ if (found->d_inode) { if (unlikely(found->d_inode != inode)) { /* This can't happen because bad inodes are unhashed. */ BUG_ON(!is_bad_inode(inode)); BUG_ON(!is_bad_inode(found->d_inode)); } - /* - * Already have the inode and the dentry attached, decrement - * the reference count to balance the iget() done - * earlier on. We found the dentry using d_lookup() so it - * cannot be disconnected and thus we do not need to worry - * about any NFS/disconnectedness issues here. - */ iput(inode); return found; } + /* * Negative dentry: instantiate it unless the inode is a directory and - * has a 'disconnected' dentry (i.e. IS_ROOT and DCACHE_DISCONNECTED), - * in which case d_move() that in place of the found dentry. + * already has a dentry. */ - if (!S_ISDIR(inode->i_mode)) { - /* Not a directory; everything is easy. */ - d_instantiate(found, inode); - return found; - } spin_lock(&dcache_lock); - if (list_empty(&inode->i_dentry)) { - /* - * Directory without a 'disconnected' dentry; we need to do - * d_instantiate() by hand because it takes dcache_lock which - * we already hold. - */ + if (!S_ISDIR(inode->i_mode) || list_empty(&inode->i_dentry)) { __d_instantiate(found, inode); spin_unlock(&dcache_lock); security_d_instantiate(found, inode); return found; } + /* - * Directory with a 'disconnected' dentry; get a reference to the - * 'disconnected' dentry. + * In case a directory already has a (disconnected) entry grab a + * reference to it, move it in place and use it. */ new = list_entry(inode->i_dentry.next, struct dentry, d_alias); dget_locked(new); spin_unlock(&dcache_lock); - /* Do security vodoo. */ security_d_instantiate(found, inode); - /* Move new in place of found. */ d_move(new, found); - /* Balance the iget() we did above. */ iput(inode); - /* Throw away found. */ dput(found); - /* Use new as the actual dentry. */ return new; err_out: |