Merge tag 'for-6.15-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs fixes from David Sterba:

 - revert device path canonicalization, this does not work as intended
   with namespaces and is not reliable in all setups

 - fix crash in scrub when checksum tree is not valid, e.g. when mounted
   with rescue=ignoredatacsums

 - fix crash when tracepoint btrfs_prelim_ref_insert is enabled

 - other minor fixups:
     - open code folio_index(), meant to be used in MM code
     - use matching type for sizeof in compression allocation

* tag 'for-6.15-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: open code folio_index() in btree_clear_folio_dirty_tag()
  Revert "btrfs: canonicalize the device path before adding it"
  btrfs: avoid NULL pointer dereference if no valid csum tree
  btrfs: handle empty eb->folios in num_extent_folios()
  btrfs: correct the order of prelim_ref arguments in btrfs__prelim_ref
  btrfs: compression: adjust cb->compressed_folios allocation type

Author: torvalds

fs/btrfs/compression.c

@@ -606,7 +606,7 @@ void btrfs_submit_compressed_read(struct btrfs_bio *bbio)
 	free_extent_map(em);
 
 	cb->nr_folios = DIV_ROUND_UP(compressed_len, PAGE_SIZE);
-	cb->compressed_folios = kcalloc(cb->nr_folios, sizeof(struct page *), GFP_NOFS);
+	cb->compressed_folios = kcalloc(cb->nr_folios, sizeof(struct folio *), GFP_NOFS);
 	if (!cb->compressed_folios) {
 		ret = BLK_STS_RESOURCE;
 		goto out_free_bio;

fs/btrfs/extent_io.c

@@ -3508,8 +3508,8 @@ static void btree_clear_folio_dirty_tag(struct folio *folio)
 	ASSERT(folio_test_locked(folio));
 	xa_lock_irq(&folio->mapping->i_pages);
 	if (!folio_test_dirty(folio))
-		__xa_clear_mark(&folio->mapping->i_pages,
-				folio_index(folio), PAGECACHE_TAG_DIRTY);
+		__xa_clear_mark(&folio->mapping->i_pages, folio->index,
+				PAGECACHE_TAG_DIRTY);
 	xa_unlock_irq(&folio->mapping->i_pages);
 }
 

fs/btrfs/extent_io.h

@@ -298,6 +298,8 @@ static inline int __pure num_extent_pages(const struct extent_buffer *eb)
  */
 static inline int __pure num_extent_folios(const struct extent_buffer *eb)
 {
+	if (!eb->folios[0])
+		return 0;
 	if (folio_order(eb->folios[0]))
 		return 1;
 	return num_extent_pages(eb);

fs/btrfs/scrub.c

@@ -1541,8 +1541,8 @@ static int scrub_find_fill_first_stripe(struct btrfs_block_group *bg,
 	u64 extent_gen;
 	int ret;
 
-	if (unlikely(!extent_root)) {
-		btrfs_err(fs_info, "no valid extent root for scrub");
+	if (unlikely(!extent_root || !csum_root)) {
+		btrfs_err(fs_info, "no valid extent or csum root for scrub");
 		return -EUCLEAN;
 	}
 	memset(stripe->sectors, 0, sizeof(struct scrub_sector_verification) *

fs/btrfs/volumes.c

@@ -733,82 +733,6 @@ const u8 *btrfs_sb_fsid_ptr(const struct btrfs_super_block *sb)
 	return has_metadata_uuid ? sb->metadata_uuid : sb->fsid;
 }
 
-/*
- * We can have very weird soft links passed in.
- * One example is "/proc/self/fd/<fd>", which can be a soft link to
- * a block device.
- *
- * But it's never a good idea to use those weird names.
- * Here we check if the path (not following symlinks) is a good one inside
- * "/dev/".
- */
-static bool is_good_dev_path(const char *dev_path)
-{
-	struct path path = { .mnt = NULL, .dentry = NULL };
-	char *path_buf = NULL;
-	char *resolved_path;
-	bool is_good = false;
-	int ret;
-
-	if (!dev_path)
-		goto out;
-
-	path_buf = kmalloc(PATH_MAX, GFP_KERNEL);
-	if (!path_buf)
-		goto out;
-
-	/*
-	 * Do not follow soft link, just check if the original path is inside
-	 * "/dev/".
-	 */
-	ret = kern_path(dev_path, 0, &path);
-	if (ret)
-		goto out;
-	resolved_path = d_path(&path, path_buf, PATH_MAX);
-	if (IS_ERR(resolved_path))
-		goto out;
-	if (strncmp(resolved_path, "/dev/", strlen("/dev/")))
-		goto out;
-	is_good = true;
-out:
-	kfree(path_buf);
-	path_put(&path);
-	return is_good;
-}
-
-static int get_canonical_dev_path(const char *dev_path, char *canonical)
-{
-	struct path path = { .mnt = NULL, .dentry = NULL };
-	char *path_buf = NULL;
-	char *resolved_path;
-	int ret;
-
-	if (!dev_path) {
-		ret = -EINVAL;
-		goto out;
-	}
-
-	path_buf = kmalloc(PATH_MAX, GFP_KERNEL);
-	if (!path_buf) {
-		ret = -ENOMEM;
-		goto out;
-	}
-
-	ret = kern_path(dev_path, LOOKUP_FOLLOW, &path);
-	if (ret)
-		goto out;
-	resolved_path = d_path(&path, path_buf, PATH_MAX);
-	if (IS_ERR(resolved_path)) {
-		ret = PTR_ERR(resolved_path);
-		goto out;
-	}
-	ret = strscpy(canonical, resolved_path, PATH_MAX);
-out:
-	kfree(path_buf);
-	path_put(&path);
-	return ret;
-}
-
 static bool is_same_device(struct btrfs_device *device, const char *new_path)
 {
 	struct path old = { .mnt = NULL, .dentry = NULL };
@@ -1513,23 +1437,12 @@ struct btrfs_device *btrfs_scan_one_device(const char *path, blk_mode_t flags,
 	bool new_device_added = false;
 	struct btrfs_device *device = NULL;
 	struct file *bdev_file;
-	char *canonical_path = NULL;
 	u64 bytenr;
 	dev_t devt;
 	int ret;
 
 	lockdep_assert_held(&uuid_mutex);
 
-	if (!is_good_dev_path(path)) {
-		canonical_path = kmalloc(PATH_MAX, GFP_KERNEL);
-		if (canonical_path) {
-			ret = get_canonical_dev_path(path, canonical_path);
-			if (ret < 0) {
-				kfree(canonical_path);
-				canonical_path = NULL;
-			}
-		}
-	}
 	/*
 	 * Avoid an exclusive open here, as the systemd-udev may initiate the
 	 * device scan which may race with the user's mount or mkfs command,
@@ -1574,8 +1487,7 @@ struct btrfs_device *btrfs_scan_one_device(const char *path, blk_mode_t flags,
 		goto free_disk_super;
 	}
 
-	device = device_list_add(canonical_path ? : path, disk_super,
-				 &new_device_added);
+	device = device_list_add(path, disk_super, &new_device_added);
 	if (!IS_ERR(device) && new_device_added)
 		btrfs_free_stale_devices(device->devt, device);
 
@@ -1584,7 +1496,6 @@ struct btrfs_device *btrfs_scan_one_device(const char *path, blk_mode_t flags,
 
 error_bdev_put:
 	fput(bdev_file);
-	kfree(canonical_path);
 
 	return device;
 }

include/trace/events/btrfs.h

@@ -1928,7 +1928,7 @@ DECLARE_EVENT_CLASS(btrfs__prelim_ref,
 	TP_PROTO(const struct btrfs_fs_info *fs_info,
 		 const struct prelim_ref *oldref,
 		 const struct prelim_ref *newref, u64 tree_size),
-	TP_ARGS(fs_info, newref, oldref, tree_size),
+	TP_ARGS(fs_info, oldref, newref, tree_size),
 
 	TP_STRUCT__entry_btrfs(
 		__field(	u64,  root_id		)