[PATCH 4.9 065/240] dm persistent data: packed struct should have an aligned() attribute too

Greg Kroah-Hartman
2021-05-20T11:09:05Z

From: Joe Thornber <ejt@redhat.com>

commit a88b2358f1da2c9f9fcc432f2e0a79617fea397c upstream.

Otherwise most non-x86 architectures (e.g. riscv, arm) will resort to
byte-by-byte access.

Cc: stable@vger.kernel.org
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/md/persistent-data/dm-btree-internal.h | 4 ++--
drivers/md/persistent-data/dm-space-map-common.h | 8 ++++----
2 files changed, 6 insertions(+), 6 deletions(-)

--- a/drivers/md/persistent-data/dm-btree-internal.h
+++ b/drivers/md/persistent-data/dm-btree-internal.h
@@ -34,12 +34,12 @@ struct node_header {
__le32 max_entries;
__le32 value_size;
__le32 padding;
-} __packed;
+} __attribute__((packed, aligned(8)));

struct btree_node {
struct node_header header;
__le64 keys[0];
-} __packed;
+} __attribute__((packed, aligned(8)));

/*
--- a/drivers/md/persistent-data/dm-space-map-common.h
+++ b/drivers/md/persistent-data/dm-space-map-common.h
@@ -33,7 +33,7 @@ struct disk_index_entry {
__le64 blocknr;
__le32 nr_free;
__le32 none_free_before;
-} __packed;
+} __attribute__ ((packed, aligned(8)));

#define MAX_METADATA_BITMAPS 255
@@ -43,7 +43,7 @@ struct disk_metadata_index {
__le64 blocknr;

struct disk_index_entry index[MAX_METADATA_BITMAPS];
-} __packed;
+} __attribute__ ((packed, aligned(8)));

struct ll_disk;

@@ -86,7 +86,7 @@ struct disk_sm_root {
__le64 nr_allocated;
__le64 bitmap_root;
__le64 ref_count_root;
-} __packed;
+} __attribute__ ((packed, aligned(8)));

#define ENTRIES_PER_BYTE 4

@@ -94,7 +94,7 @@ struct disk_bitmap_header {
__le32 csum;
__le32 not_used;
__le64 blocknr;
-} __packed;
+} __attribute__ ((packed, aligned(8)));

enum allocation_event {
SM_NONE,