dm persistent data: packed struct should have an aligned() attribute too

commit a88b2358f1da2c9f9fcc432f2e0a79617fea397c upstream.

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

Cc: [email protected]
Signed-off-by: Joe Thornber <[email protected]>
Signed-off-by: Mike Snitzer <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

Author: jthornber

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)));
 
 
 /*

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;
 
@@ -86,15 +86,15 @@ struct disk_sm_root {
 	__le64 nr_allocated;
 	__le64 bitmap_root;
 	__le64 ref_count_root;
-} __packed;
+} __attribute__ ((packed, aligned(8)));
 
 #define ENTRIES_PER_BYTE 4
 
 struct disk_bitmap_header {
 	__le32 csum;
 	__le32 not_used;
 	__le64 blocknr;
-} __packed;
+} __attribute__ ((packed, aligned(8)));
 
 enum allocation_event {
 	SM_NONE,