btrfs: scrub: Don't use inode page cache in scrub_handle_errored_block()

[sfrench/cifs-2.6.git] / fs / btrfs / scrub.c

diff --git a/fs/btrfs/scrub.c b/fs/btrfs/scrub.c
index 1a2066ac6fe7cbe488a92fe92c9a25ed2d15dd0b..6702896cdb8f7bcdb93a393f5ee3482498376445 100644 (file)
--- a/fs/btrfs/scrub.c
+++ b/fs/btrfs/scrub.c
@@ -1,19 +1,6 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * Copyright (C) 2011, 2012 STRATO.  All rights reserved.
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public
- * License v2 as published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * General Public License for more details.
- *
- * You should have received a copy of the GNU General Public
- * License along with this program; if not, write to the
- * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
- * Boston, MA 021110-1307, USA.
  */
 
 #include <linux/blkdev.h>
@@ -1164,11 +1151,6 @@ static int scrub_handle_errored_block(struct scrub_block *sblock_to_check)
                return ret;
        }
 
-       if (sctx->is_dev_replace && !is_metadata && !have_csum) {
-               sblocks_for_recheck = NULL;
-               goto nodatasum_case;
-       }
-
        /*
         * read all mirrors one after the other. This includes to
         * re-read the extent or metadata block that failed (that was
@@ -1281,13 +1263,19 @@ static int scrub_handle_errored_block(struct scrub_block *sblock_to_check)
                goto out;
        }
 
-       if (!is_metadata && !have_csum) {
+       /*
+        * NOTE: Even for nodatasum case, it's still possible that it's a
+        * compressed data extent, thus scrub_fixup_nodatasum(), which write
+        * inode page cache onto disk, could cause serious data corruption.
+        *
+        * So here we could only read from disk, and hope our recovery could
+        * reach disk before the newer write.
+        */
+       if (0 && !is_metadata && !have_csum) {
                struct scrub_fixup_nodatasum *fixup_nodatasum;
 
                WARN_ON(sctx->is_dev_replace);
 
-nodatasum_case:
-
                /*
                 * !is_metadata and !have_csum, this means that the data
                 * might not be COWed, that it might be modified
@@ -2812,7 +2800,7 @@ static int scrub_extent(struct scrub_ctx *sctx, struct map_lookup *map,
                        have_csum = scrub_find_csum(sctx, logical, csum);
                        if (have_csum == 0)
                                ++sctx->stat.no_csum;
-                       if (sctx->is_dev_replace && !have_csum) {
+                       if (0 && sctx->is_dev_replace && !have_csum) {
                                ret = copy_nocow_pages(sctx, logical, l,
                                                       mirror_num,
                                                      physical_for_dev_replace);
@@ -3997,6 +3985,7 @@ int scrub_enumerate_chunks(struct scrub_ctx *sctx,
                        spin_lock(&fs_info->unused_bgs_lock);
                        if (list_empty(&cache->bg_list)) {
                                btrfs_get_block_group(cache);
+                               trace_btrfs_add_unused_block_group(cache);
                                list_add_tail(&cache->bg_list,
                                              &fs_info->unused_bgs);
                        }