fs: btrfs: Fix cache alignment bugs
The btrfs implementation passes cache-unaligned buffers into the
block layer, which triggers cache alignment problems down in the
block device drivers. Align the buffers to prevent this.
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Marek Behun <marek.behun@nic.cz>
diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index 4da36a9..18b47d9 100644
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -7,6 +7,7 @@
#include "btrfs.h"
#include <malloc.h>
+#include <memalign.h>
int btrfs_comp_keys(struct btrfs_key *a, struct btrfs_key *b)
{
@@ -105,23 +106,24 @@
static int read_tree_node(u64 physical, union btrfs_tree_node **buf)
{
- struct btrfs_header hdr;
- unsigned long size, offset = sizeof(hdr);
+ ALLOC_CACHE_ALIGN_BUFFER(struct btrfs_header, hdr,
+ sizeof(struct btrfs_header));
+ unsigned long size, offset = sizeof(*hdr);
union btrfs_tree_node *res;
u32 i;
- if (!btrfs_devread(physical, sizeof(hdr), &hdr))
+ if (!btrfs_devread(physical, sizeof(*hdr), hdr))
return -1;
- btrfs_header_to_cpu(&hdr);
+ btrfs_header_to_cpu(hdr);
- if (hdr.level)
+ if (hdr->level)
size = sizeof(struct btrfs_node)
- + hdr.nritems * sizeof(struct btrfs_key_ptr);
+ + hdr->nritems * sizeof(struct btrfs_key_ptr);
else
size = btrfs_info.sb.nodesize;
- res = malloc(size);
+ res = malloc_cache_aligned(size);
if (!res) {
debug("%s: malloc failed\n", __func__);
return -1;
@@ -133,12 +135,12 @@
return -1;
}
- res->header = hdr;
- if (hdr.level)
- for (i = 0; i < hdr.nritems; ++i)
+ memcpy(&res->header, hdr, sizeof(*hdr));
+ if (hdr->level)
+ for (i = 0; i < hdr->nritems; ++i)
btrfs_key_ptr_to_cpu(&res->node.ptrs[i]);
else
- for (i = 0; i < hdr.nritems; ++i)
+ for (i = 0; i < hdr->nritems; ++i)
btrfs_item_to_cpu(&res->leaf.items[i]);
*buf = res;