[1/3] btrfs: explicitly mark BTRFS_MOUNT_ enum as 64bit

Commit Message

Qu Wenruo Sept. 22, 2023, 2:55 a.m. UTC

Currently we already have 29 BTRFS_MOUNT_* enums, and with several new
incoming mount options, we will go beyond 32bits.

For now we use "unsigned long" for fs_info->mount_opt, which is 64bit
for x86_64, but it's not always the case for all architects.

So here we explicitly mark BTRFS_MOUNT_* enum and
btrfs_fs_info::mount_opt as 64bit to avoid overflow.

For common architects like x86_64 and aarch64, this change makes no
difference, but for older 32bit systems it would cause a slight memory
usage increase per-fs (4 bytes increase + possible 4 bytes hole).

Signed-off-by: Qu Wenruo <[e-mail]>
---
 fs/btrfs/fs.h | 62 +++++++++++++++++++++++++--------------------------
 1 file changed, 31 insertions(+), 31 deletions(-)

Patch

diff --git a/fs/btrfs/fs.h b/fs/btrfs/fs.h
index 19f9a444bcd8..cec28d6b20bc 100644
--- a/fs/btrfs/fs.h
+++ b/fs/btrfs/fs.h
@@ -158,36 +158,36 @@  enum {
  * Note: don't forget to add new options to btrfs_show_options()
  */
 enum {
-	BTRFS_MOUNT_NODATASUM			= (1UL << 0),
-	BTRFS_MOUNT_NODATACOW			= (1UL << 1),
-	BTRFS_MOUNT_NOBARRIER			= (1UL << 2),
-	BTRFS_MOUNT_SSD				= (1UL << 3),
-	BTRFS_MOUNT_DEGRADED			= (1UL << 4),
-	BTRFS_MOUNT_COMPRESS			= (1UL << 5),
-	BTRFS_MOUNT_NOTREELOG   		= (1UL << 6),
-	BTRFS_MOUNT_FLUSHONCOMMIT		= (1UL << 7),
-	BTRFS_MOUNT_SSD_SPREAD			= (1UL << 8),
-	BTRFS_MOUNT_NOSSD			= (1UL << 9),
-	BTRFS_MOUNT_DISCARD_SYNC		= (1UL << 10),
-	BTRFS_MOUNT_FORCE_COMPRESS      	= (1UL << 11),
-	BTRFS_MOUNT_SPACE_CACHE			= (1UL << 12),
-	BTRFS_MOUNT_CLEAR_CACHE			= (1UL << 13),
-	BTRFS_MOUNT_USER_SUBVOL_RM_ALLOWED	= (1UL << 14),
-	BTRFS_MOUNT_ENOSPC_DEBUG		= (1UL << 15),
-	BTRFS_MOUNT_AUTO_DEFRAG			= (1UL << 16),
-	BTRFS_MOUNT_USEBACKUPROOT		= (1UL << 17),
-	BTRFS_MOUNT_SKIP_BALANCE		= (1UL << 18),
-	BTRFS_MOUNT_PANIC_ON_FATAL_ERROR	= (1UL << 19),
-	BTRFS_MOUNT_RESCAN_UUID_TREE		= (1UL << 20),
-	BTRFS_MOUNT_FRAGMENT_DATA		= (1UL << 21),
-	BTRFS_MOUNT_FRAGMENT_METADATA		= (1UL << 22),
-	BTRFS_MOUNT_FREE_SPACE_TREE		= (1UL << 23),
-	BTRFS_MOUNT_NOLOGREPLAY			= (1UL << 24),
-	BTRFS_MOUNT_REF_VERIFY			= (1UL << 25),
-	BTRFS_MOUNT_DISCARD_ASYNC		= (1UL << 26),
-	BTRFS_MOUNT_IGNOREBADROOTS		= (1UL << 27),
-	BTRFS_MOUNT_IGNOREDATACSUMS		= (1UL << 28),
-	BTRFS_MOUNT_NODISCARD			= (1UL << 29),
+	BTRFS_MOUNT_NODATASUM			= (1ULL << 0),
+	BTRFS_MOUNT_NODATACOW			= (1ULL << 1),
+	BTRFS_MOUNT_NOBARRIER			= (1ULL << 2),
+	BTRFS_MOUNT_SSD				= (1ULL << 3),
+	BTRFS_MOUNT_DEGRADED			= (1ULL << 4),
+	BTRFS_MOUNT_COMPRESS			= (1ULL << 5),
+	BTRFS_MOUNT_NOTREELOG			= (1ULL << 6),
+	BTRFS_MOUNT_FLUSHONCOMMIT		= (1ULL << 7),
+	BTRFS_MOUNT_SSD_SPREAD			= (1ULL << 8),
+	BTRFS_MOUNT_NOSSD			= (1ULL << 9),
+	BTRFS_MOUNT_DISCARD_SYNC		= (1ULL << 10),
+	BTRFS_MOUNT_FORCE_COMPRESS		= (1ULL << 11),
+	BTRFS_MOUNT_SPACE_CACHE			= (1ULL << 12),
+	BTRFS_MOUNT_CLEAR_CACHE			= (1ULL << 13),
+	BTRFS_MOUNT_USER_SUBVOL_RM_ALLOWED	= (1ULL << 14),
+	BTRFS_MOUNT_ENOSPC_DEBUG		= (1ULL << 15),
+	BTRFS_MOUNT_AUTO_DEFRAG			= (1ULL << 16),
+	BTRFS_MOUNT_USEBACKUPROOT		= (1ULL << 17),
+	BTRFS_MOUNT_SKIP_BALANCE		= (1ULL << 18),
+	BTRFS_MOUNT_PANIC_ON_FATAL_ERROR	= (1ULL << 19),
+	BTRFS_MOUNT_RESCAN_UUID_TREE		= (1ULL << 20),
+	BTRFS_MOUNT_FRAGMENT_DATA		= (1ULL << 21),
+	BTRFS_MOUNT_FRAGMENT_METADATA		= (1ULL << 22),
+	BTRFS_MOUNT_FREE_SPACE_TREE		= (1ULL << 23),
+	BTRFS_MOUNT_NOLOGREPLAY			= (1ULL << 24),
+	BTRFS_MOUNT_REF_VERIFY			= (1ULL << 25),
+	BTRFS_MOUNT_DISCARD_ASYNC		= (1ULL << 26),
+	BTRFS_MOUNT_IGNOREBADROOTS		= (1ULL << 27),
+	BTRFS_MOUNT_IGNOREDATACSUMS		= (1ULL << 28),
+	BTRFS_MOUNT_NODISCARD			= (1ULL << 29),
 };
 
 /*
@@ -429,7 +429,7 @@  struct btrfs_fs_info {
 	 * required instead of the faster short fsync log commits
 	 */
 	u64 last_trans_log_full_commit;
-	unsigned long mount_opt;
+	u64 mount_opt;
 
 	unsigned long compress_type:4;
 	unsigned int compress_level;