Patch "f2fs: don't rely on F2FS_MAP_* in f2fs_iomap_begin" has been added to the 6.2-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    f2fs: don't rely on F2FS_MAP_* in f2fs_iomap_begin

to the 6.2-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     f2fs-don-t-rely-on-f2fs_map_-in-f2fs_iomap_begin.patch
and it can be found in the queue-6.2 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit 66da1a43123d4fa856b2a21c2b5dc4bd3ccc094b
Author: Christoph Hellwig <hch@xxxxxx>
Date:   Mon Nov 28 10:15:09 2022 +0100

    f2fs: don't rely on F2FS_MAP_* in f2fs_iomap_begin
    
    [ Upstream commit 8d3c1fa3fa5eacfd14f5b018eddb6c1a91c57783 ]
    
    When testing with a mixed zoned / convention device combination, there
    are regular but not 100% reproducible failures in xfstests generic/113
    where the __is_valid_data_blkaddr assert hits due to finding a hole.
    
    This seems to be because f2fs_map_blocks can set this flag on a hole
    when it was found in the extent cache.
    
    Rework f2fs_iomap_begin to just check the special block numbers directly.
    This has the added benefits of the WARN_ON showing which invalid block
    address we found, and being properly error out on delalloc blocks that
    are confusingly called unwritten but not actually suitable for direct
    I/O.
    
    Fixes: 1517c1a7a445 ("f2fs: implement iomap operations")
    Signed-off-by: Christoph Hellwig <hch@xxxxxx>
    Reviewed-by: Chao Yu <chao@xxxxxxxxxx>
    Signed-off-by: Jaegeuk Kim <jaegeuk@xxxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index 8cca566baf3ab..5263d97bef1dd 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -4155,20 +4155,24 @@ static int f2fs_iomap_begin(struct inode *inode, loff_t offset, loff_t length,
 	 */
 	map.m_len = fscrypt_limit_io_blocks(inode, map.m_lblk, map.m_len);
 
-	if (map.m_flags & (F2FS_MAP_MAPPED | F2FS_MAP_UNWRITTEN)) {
-		iomap->length = blks_to_bytes(inode, map.m_len);
-		if (map.m_flags & F2FS_MAP_MAPPED) {
-			iomap->type = IOMAP_MAPPED;
-			iomap->flags |= IOMAP_F_MERGED;
-		} else {
-			iomap->type = IOMAP_UNWRITTEN;
-		}
-		if (WARN_ON_ONCE(!__is_valid_data_blkaddr(map.m_pblk)))
-			return -EINVAL;
+	/*
+	 * We should never see delalloc or compressed extents here based on
+	 * prior flushing and checks.
+	 */
+	if (WARN_ON_ONCE(map.m_pblk == NEW_ADDR))
+		return -EINVAL;
+	if (WARN_ON_ONCE(map.m_pblk == COMPRESS_ADDR))
+		return -EINVAL;
 
+	if (map.m_pblk != NULL_ADDR) {
+		iomap->length = blks_to_bytes(inode, map.m_len);
+		iomap->type = IOMAP_MAPPED;
+		iomap->flags |= IOMAP_F_MERGED;
 		iomap->bdev = map.m_bdev;
 		iomap->addr = blks_to_bytes(inode, map.m_pblk);
 	} else {
+		if (flags & IOMAP_WRITE)
+			return -ENOTBLK;
 		iomap->length = blks_to_bytes(inode, next_pgofs) -
 				iomap->offset;
 		iomap->type = IOMAP_HOLE;