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[1/2] btrfs-progs: fix the conflicting super flags

Message ID bd2df0d12b09a29ea39d7a6b1692b0523592002d.1717819918.git.wqu@suse.com (mailing list archive)
State New, archived
Headers show
Series btrfs-progs: fix the conflicting super flags | expand

Commit Message

Qu Wenruo June 8, 2024, 4:13 a.m. UTC
[BUG]
There is a bug report that a canceled csum conversion (still
experimental feature) resulted unexpected super flags:

csum_type		0 (crc32c)
csum_size		4
csum			0x14973811 [match]
bytenr			65536
flags			0x1000000001
			( WRITTEN |
			  CHANGING_FSID_V2 )
magic			_BHRfS_M [match]

Meanwhile for a fs under csum conversion it should have either
CHANGING_DATA_CSUM or CHANGING_META_CSUM.

[CAUSE]
It turns out that, due to btrfs-progs keeps its own extra flags inside
its own ctree.h headers, not the shared uapi headers, we have
conflicting super flags:

kernel-shared/uapi/btrfs_tree.h:#define BTRFS_SUPER_FLAG_METADUMP_V2	(1ULL << 34)
kernel-shared/uapi/btrfs_tree.h:#define BTRFS_SUPER_FLAG_CHANGING_FSID	(1ULL << 35)
kernel-shared/uapi/btrfs_tree.h:#define BTRFS_SUPER_FLAG_CHANGING_FSID_V2 (1ULL << 36)
kernel-shared/ctree.h:#define BTRFS_SUPER_FLAG_CHANGING_DATA_CSUM	(1ULL << 36)
kernel-shared/ctree.h:#define BTRFS_SUPER_FLAG_CHANGING_META_CSUM	(1ULL << 37)

Note that CHANGING_FSID_V2 is conflicting with CHANGING_DATA_CSUM.

[FIX]
Cross port the proper updated uapi headers into btrfs-progs, and remove
the definition from ctree.h.

This would change the value for CHANGING_DATA_CSUM and
CHANGING_META_CSUM, but considering they are experimental features, and
kernel would reject them anyway, the damage is not that huge and we can
accept such change before exposing it to end users.

Signed-off-by: Qu Wenruo <wqu@suse.com>
---
 kernel-shared/ctree.h           | 10 ----------
 kernel-shared/uapi/btrfs_tree.h |  8 ++++++++
 2 files changed, 8 insertions(+), 10 deletions(-)
diff mbox series

Patch

diff --git a/kernel-shared/ctree.h b/kernel-shared/ctree.h
index 444d206e0a2c..1341a418726b 100644
--- a/kernel-shared/ctree.h
+++ b/kernel-shared/ctree.h
@@ -59,16 +59,6 @@  static inline unsigned long btrfs_chunk_item_size(int num_stripes)
 		sizeof(struct btrfs_stripe) * (num_stripes - 1);
 }
 
-#define BTRFS_SUPER_FLAG_CHANGING_DATA_CSUM	(1ULL << 36)
-#define BTRFS_SUPER_FLAG_CHANGING_META_CSUM	(1ULL << 37)
-
-/*
- * The fs is undergoing block group tree feature change.
- * If no BLOCK_GROUP_TREE compat ro flag, it's changing from regular
- * bg item in extent tree to new bg tree.
- */
-#define BTRFS_SUPER_FLAG_CHANGING_BG_TREE	(1ULL << 38)
-
 static inline u32 __BTRFS_LEAF_DATA_SIZE(u32 nodesize)
 {
 	return nodesize - sizeof(struct btrfs_header);
diff --git a/kernel-shared/uapi/btrfs_tree.h b/kernel-shared/uapi/btrfs_tree.h
index e2ac228bcccc..23e18e735959 100644
--- a/kernel-shared/uapi/btrfs_tree.h
+++ b/kernel-shared/uapi/btrfs_tree.h
@@ -758,6 +758,14 @@  struct btrfs_free_space_header {
 #define BTRFS_SUPER_FLAG_CHANGING_FSID	(1ULL << 35)
 #define BTRFS_SUPER_FLAG_CHANGING_FSID_V2 (1ULL << 36)
 
+/*
+ * Those are temporaray flags utilized by btrfs-progs to do offline conversion.
+ * They are rejected by kernel.
+ * But still keep them all here to avoid conflicts.
+ */
+#define BTRFS_SUPER_FLAG_CHANGING_BG_TREE	(1ULL << 38)
+#define BTRFS_SUPER_FLAG_CHANGING_DATA_CSUM	(1ULL << 39)
+#define BTRFS_SUPER_FLAG_CHANGING_META_CSUM	(1ULL << 40)
 
 /*
  * items in the extent btree are used to record the objectid of the