From: Qu Wenruo <quwenruo@cn.fujitsu.com>
Date: Mon, 11 May 2015 08:08:45 +0000 (+0800)
Subject: btrfs-progs: Add open_ctree check for uuid changing
X-Git-Tag: upstream/4.16.1~2273
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=2259f03439bd697b64efdb09dfc75638f24c4b48;p=platform%2Fupstream%2Fbtrfs-progs.git

btrfs-progs: Add open_ctree check for uuid changing

Now open_ctree will exit if it found the superblock is marked
CHANGING_FSID, except given IGNORE_FSID open ctree flags.

Kernel will do the same thing later.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
[removed the chunk tree flag, reworded the error message]
Signed-off-by: David Sterba <dsterba@suse.cz>
---

diff --git a/ctree.h b/ctree.h
index 7c1bef5..98cb1fb 100644
--- a/ctree.h
+++ b/ctree.h
@@ -1011,6 +1011,7 @@ struct btrfs_fs_info {
 	unsigned int is_chunk_recover:1;
 	unsigned int quota_enabled:1;
 	unsigned int suppress_check_block_errors:1;
+	unsigned int ignore_fsid_mismatch:1;
 
 	int (*free_extent_hook)(struct btrfs_trans_handle *trans,
 				struct btrfs_root *root,
diff --git a/disk-io.c b/disk-io.c
index c1cf146..3daed3b 100644
--- a/disk-io.c
+++ b/disk-io.c
@@ -49,7 +49,8 @@ static int check_tree_block(struct btrfs_root *root, struct extent_buffer *buf)
 
 	fs_devices = root->fs_info->fs_devices;
 	while (fs_devices) {
-		if (!memcmp_extent_buffer(buf, fs_devices->fsid,
+		if (root->fs_info->ignore_fsid_mismatch ||
+		    !memcmp_extent_buffer(buf, fs_devices->fsid,
 					  btrfs_header_fsid(),
 					  BTRFS_FSID_SIZE)) {
 			ret = 0;
@@ -1149,6 +1150,8 @@ static struct btrfs_fs_info *__open_ctree_fd(int fp, const char *path,
 		fs_info->on_restoring = 1;
 	if (flags & OPEN_CTREE_SUPPRESS_CHECK_BLOCK_ERRORS)
 		fs_info->suppress_check_block_errors = 1;
+	if (flags & OPEN_CTREE_IGNORE_FSID_MISMATCH)
+		fs_info->ignore_fsid_mismatch = 1;
 
 	ret = btrfs_scan_fs_devices(fp, path, &fs_devices, sb_bytenr,
 				    (flags & OPEN_CTREE_RECOVER_SUPER),
@@ -1180,6 +1183,12 @@ static struct btrfs_fs_info *__open_ctree_fd(int fp, const char *path,
 		goto out_devices;
 	}
 
+	if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_CHANGING_FSID &&
+	    !fs_info->ignore_fsid_mismatch) {
+		fprintf(stderr, "ERROR: Filesystem UUID change in progress\n");
+		goto out_devices;
+	}
+
 	memcpy(fs_info->fsid, &disk_super->fsid, BTRFS_FSID_SIZE);
 
 	ret = btrfs_check_fs_compatibility(fs_info->super_copy,
diff --git a/disk-io.h b/disk-io.h
index 4caebeb..19f333e 100644
--- a/disk-io.h
+++ b/disk-io.h
@@ -49,6 +49,8 @@ enum btrfs_open_ctree_flags {
 	 * tree bits.
 	 * Like split PARTIAL into SKIP_CSUM/SKIP_EXTENT
 	 */
+
+	OPEN_CTREE_IGNORE_FSID_MISMATCH	= (1 << 10)
 };
 
 static inline u64 btrfs_sb_offset(int mirror)