Merge tag 'for-6.8-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs fixes from David Sterba:
 "A few regular fixes and one fix for space reservation regression since
  6.7 that users have been reporting:

   - fix over-reservation of metadata chunks due to not keeping proper
     balance between global block reserve and delayed refs reserve; in
     practice this leaves behind empty metadata block groups, the
     workaround is to reclaim them by using the '-musage=1' balance
     filter

   - other space reservation fixes:
      - do not delete unused block group if it may be used soon
      - do not reserve space for checksums for NOCOW files

   - fix extent map assertion failure when writing out free space inode

   - reject encoded write if inode has nodatasum flag set

   - fix chunk map leak when loading block group zone info"

* tag 'for-6.8-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: don't refill whole delayed refs block reserve when starting transaction
  btrfs: zoned: fix chunk map leak when loading block group zone info
  btrfs: reject encoded write if inode has nodatasum flag set
  btrfs: don't reserve space for checksums when writing to nocow files
  btrfs: add new unused block groups to the list of unused block groups
  btrfs: do not delete unused block group if it may be used soon
  btrfs: add and use helper to check if block group is used
  btrfs: don't drop extent_map for free space inode on write error

1 files changed, 24 insertions, 2 deletions

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 1eb93d3962aa..f88e0ca8331d 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -3184,8 +3184,23 @@ out:
 			unwritten_start += logical_len;
 		clear_extent_uptodate(io_tree, unwritten_start, end, NULL);
 
-		/* Drop extent maps for the part of the extent we didn't write. */
-		btrfs_drop_extent_map_range(inode, unwritten_start, end, false);
+		/*
+		 * Drop extent maps for the part of the extent we didn't write.
+		 *
+		 * We have an exception here for the free_space_inode, this is
+		 * because when we do btrfs_get_extent() on the free space inode
+		 * we will search the commit root.  If this is a new block group
+		 * we won't find anything, and we will trip over the assert in
+		 * writepage where we do ASSERT(em->block_start !=
+		 * EXTENT_MAP_HOLE).
+		 *
+		 * Theoretically we could also skip this for any NOCOW extent as
+		 * we don't mess with the extent map tree in the NOCOW case, but
+		 * for now simply skip this if we are the free space inode.
+		 */
+		if (!btrfs_is_free_space_inode(inode))
+			btrfs_drop_extent_map_range(inode, unwritten_start,
+						    end, false);
 
 		/*
 		 * If the ordered extent had an IOERR or something else went
@@ -10273,6 +10288,13 @@ ssize_t btrfs_do_encoded_write(struct kiocb *iocb, struct iov_iter *from,
 	if (encoded->encryption != BTRFS_ENCODED_IO_ENCRYPTION_NONE)
 		return -EINVAL;
 
+	/*
+	 * Compressed extents should always have checksums, so error out if we
+	 * have a NOCOW file or inode was created while mounted with NODATASUM.
+	 */
+	if (inode->flags & BTRFS_INODE_NODATASUM)
+		return -EINVAL;
+
 	orig_count = iov_iter_count(from);
 
 	/* The extent size must be sane. */