diff options
| -rw-r--r-- | fs/libfs.c | 49 |
1 files changed, 25 insertions, 24 deletions
diff --git a/fs/libfs.c b/fs/libfs.c index 8e023b08a240..540611b99b9a 100644 --- a/fs/libfs.c +++ b/fs/libfs.c @@ -92,14 +92,13 @@ EXPORT_SYMBOL(dcache_dir_close); /* * Returns an element of siblings' list. * We are looking for <count>th positive after <p>; if - * found, dentry is grabbed and passed to caller via *<res>. - * If no such element exists, the anchor of list is returned - * and *<res> is set to NULL. + * found, dentry is grabbed and returned to caller. + * If no such element exists, NULL is returned. */ -static struct list_head *scan_positives(struct dentry *cursor, +static struct dentry *scan_positives(struct dentry *cursor, struct list_head *p, loff_t count, - struct dentry **res) + struct dentry *last) { struct dentry *dentry = cursor->d_parent, *found = NULL; @@ -127,9 +126,8 @@ static struct list_head *scan_positives(struct dentry *cursor, } } spin_unlock(&dentry->d_lock); - dput(*res); - *res = found; - return p; + dput(last); + return found; } loff_t dcache_dir_lseek(struct file *file, loff_t offset, int whence) @@ -149,25 +147,22 @@ loff_t dcache_dir_lseek(struct file *file, loff_t offset, int whence) if (offset != file->f_pos) { struct dentry *cursor = file->private_data; struct dentry *to = NULL; - struct list_head *p; - file->f_pos = offset; inode_lock_shared(dentry->d_inode); - if (file->f_pos > 2) { - p = scan_positives(cursor, &dentry->d_subdirs, - file->f_pos - 2, &to); - spin_lock(&dentry->d_lock); - list_move(&cursor->d_child, p); - spin_unlock(&dentry->d_lock); - } else { - spin_lock(&dentry->d_lock); + if (offset > 2) + to = scan_positives(cursor, &dentry->d_subdirs, + offset - 2, NULL); + spin_lock(&dentry->d_lock); + if (to) + list_move(&cursor->d_child, &to->d_child); + else list_del_init(&cursor->d_child); - spin_unlock(&dentry->d_lock); - } - + spin_unlock(&dentry->d_lock); dput(to); + file->f_pos = offset; + inode_unlock_shared(dentry->d_inode); } return offset; @@ -199,17 +194,23 @@ int dcache_readdir(struct file *file, struct dir_context *ctx) if (ctx->pos == 2) p = anchor; - else + else if (!list_empty(&cursor->d_child)) p = &cursor->d_child; + else + return 0; - while ((p = scan_positives(cursor, p, 1, &next)) != anchor) { + while ((next = scan_positives(cursor, p, 1, next)) != NULL) { if (!dir_emit(ctx, next->d_name.name, next->d_name.len, d_inode(next)->i_ino, dt_type(d_inode(next)))) break; ctx->pos++; + p = &next->d_child; } spin_lock(&dentry->d_lock); - list_move_tail(&cursor->d_child, p); + if (next) + list_move_tail(&cursor->d_child, &next->d_child); + else + list_del_init(&cursor->d_child); spin_unlock(&dentry->d_lock); dput(next); |