1 files changed, 2 insertions, 165 deletions

diff --git a/fs/fuse/passthrough.c b/fs/fuse/passthrough.c
index eb97ac009e75..72de97c03d0e 100644
--- a/fs/fuse/passthrough.c
+++ b/fs/fuse/passthrough.c
@@ -144,171 +144,12 @@ ssize_t fuse_passthrough_mmap(struct file *file, struct vm_area_struct *vma)
 	return backing_file_mmap(backing_file, vma, &ctx);
 }
 
-struct fuse_backing *fuse_backing_get(struct fuse_backing *fb)
-{
-	if (fb && refcount_inc_not_zero(&fb->count))
-		return fb;
-	return NULL;
-}
-
-static void fuse_backing_free(struct fuse_backing *fb)
-{
-	pr_debug("%s: fb=0x%p\n", __func__, fb);
-
-	if (fb->file)
-		fput(fb->file);
-	put_cred(fb->cred);
-	kfree_rcu(fb, rcu);
-}
-
-void fuse_backing_put(struct fuse_backing *fb)
-{
-	if (fb && refcount_dec_and_test(&fb->count))
-		fuse_backing_free(fb);
-}
-
-void fuse_backing_files_init(struct fuse_conn *fc)
-{
-	idr_init(&fc->backing_files_map);
-}
-
-static int fuse_backing_id_alloc(struct fuse_conn *fc, struct fuse_backing *fb)
-{
-	int id;
-
-	idr_preload(GFP_KERNEL);
-	spin_lock(&fc->lock);
-	/* FIXME: xarray might be space inefficient */
-	id = idr_alloc_cyclic(&fc->backing_files_map, fb, 1, 0, GFP_ATOMIC);
-	spin_unlock(&fc->lock);
-	idr_preload_end();
-
-	WARN_ON_ONCE(id == 0);
-	return id;
-}
-
-static struct fuse_backing *fuse_backing_id_remove(struct fuse_conn *fc,
-						   int id)
-{
-	struct fuse_backing *fb;
-
-	spin_lock(&fc->lock);
-	fb = idr_remove(&fc->backing_files_map, id);
-	spin_unlock(&fc->lock);
-
-	return fb;
-}
-
-static int fuse_backing_id_free(int id, void *p, void *data)
-{
-	struct fuse_backing *fb = p;
-
-	WARN_ON_ONCE(refcount_read(&fb->count) != 1);
-	fuse_backing_free(fb);
-	return 0;
-}
-
-void fuse_backing_files_free(struct fuse_conn *fc)
-{
-	idr_for_each(&fc->backing_files_map, fuse_backing_id_free, NULL);
-	idr_destroy(&fc->backing_files_map);
-}
-
-int fuse_backing_open(struct fuse_conn *fc, struct fuse_backing_map *map)
-{
-	struct file *file;
-	struct super_block *backing_sb;
-	struct fuse_backing *fb = NULL;
-	int res;
-
-	pr_debug("%s: fd=%d flags=0x%x\n", __func__, map->fd, map->flags);
-
-	/* TODO: relax CAP_SYS_ADMIN once backing files are visible to lsof */
-	res = -EPERM;
-	if (!fc->passthrough || !capable(CAP_SYS_ADMIN))
-		goto out;
-
-	res = -EINVAL;
-	if (map->flags || map->padding)
-		goto out;
-
-	file = fget_raw(map->fd);
-	res = -EBADF;
-	if (!file)
-		goto out;
-
-	/* read/write/splice/mmap passthrough only relevant for regular files */
-	res = d_is_dir(file->f_path.dentry) ? -EISDIR : -EINVAL;
-	if (!d_is_reg(file->f_path.dentry))
-		goto out_fput;
-
-	backing_sb = file_inode(file)->i_sb;
-	res = -ELOOP;
-	if (backing_sb->s_stack_depth >= fc->max_stack_depth)
-		goto out_fput;
-
-	fb = kmalloc(sizeof(struct fuse_backing), GFP_KERNEL);
-	res = -ENOMEM;
-	if (!fb)
-		goto out_fput;
-
-	fb->file = file;
-	fb->cred = prepare_creds();
-	refcount_set(&fb->count, 1);
-
-	res = fuse_backing_id_alloc(fc, fb);
-	if (res < 0) {
-		fuse_backing_free(fb);
-		fb = NULL;
-	}
-
-out:
-	pr_debug("%s: fb=0x%p, ret=%i\n", __func__, fb, res);
-
-	return res;
-
-out_fput:
-	fput(file);
-	goto out;
-}
-
-int fuse_backing_close(struct fuse_conn *fc, int backing_id)
-{
-	struct fuse_backing *fb = NULL;
-	int err;
-
-	pr_debug("%s: backing_id=%d\n", __func__, backing_id);
-
-	/* TODO: relax CAP_SYS_ADMIN once backing files are visible to lsof */
-	err = -EPERM;
-	if (!fc->passthrough || !capable(CAP_SYS_ADMIN))
-		goto out;
-
-	err = -EINVAL;
-	if (backing_id <= 0)
-		goto out;
-
-	err = -ENOENT;
-	fb = fuse_backing_id_remove(fc, backing_id);
-	if (!fb)
-		goto out;
-
-	fuse_backing_put(fb);
-	err = 0;
-out:
-	pr_debug("%s: fb=0x%p, err=%i\n", __func__, fb, err);
-
-	return err;
-}
-
 /*
  * Setup passthrough to a backing file.
  *
  * Returns an fb object with elevated refcount to be stored in fuse inode.
  */
-struct fuse_backing *fuse_passthrough_open(struct file *file,
-					   struct inode *inode,
-					   int backing_id)
+struct fuse_backing *fuse_passthrough_open(struct file *file, int backing_id)
 {
 	struct fuse_file *ff = file->private_data;
 	struct fuse_conn *fc = ff->fm->fc;
@@ -320,12 +161,8 @@ struct fuse_backing *fuse_passthrough_open(struct file *file,
 	if (backing_id <= 0)
 		goto out;
 
-	rcu_read_lock();
-	fb = idr_find(&fc->backing_files_map, backing_id);
-	fb = fuse_backing_get(fb);
-	rcu_read_unlock();
-
 	err = -ENOENT;
+	fb = fuse_backing_lookup(fc, backing_id);
 	if (!fb)
 		goto out;