btrfs: directly call into crypto framework for checksumming
Currently btrfs_csum_data() relied on the crc32c() wrapper around the
crypto framework for calculating the CRCs.
As we have our own crypto_shash structure in the fs_info now, we can
directly call into the crypto framework without going trough the wrapper.
This way we can even remove the btrfs_csum_data() and btrfs_csum_final()
wrappers.
The module dependency on crc32c is preserved via MODULE_SOFTDEP("pre:
crc32c"), which was previously provided by LIBCRC32C config option doing
the same.
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 34222bb..6c7dc24 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -246,16 +246,6 @@ struct extent_map *btree_get_extent(struct btrfs_inode *inode,
return em;
}
-u32 btrfs_csum_data(const char *data, u32 seed, size_t len)
-{
- return crc32c(seed, data, len);
-}
-
-void btrfs_csum_final(u32 crc, u8 *result)
-{
- put_unaligned_le32(~crc, result);
-}
-
/*
* Compute the csum of a btree block and store the result to provided buffer.
*
@@ -263,6 +253,8 @@ void btrfs_csum_final(u32 crc, u8 *result)
*/
static int csum_tree_block(struct extent_buffer *buf, u8 *result)
{
+ struct btrfs_fs_info *fs_info = buf->fs_info;
+ SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
unsigned long len;
unsigned long cur_len;
unsigned long offset = BTRFS_CSUM_SIZE;
@@ -270,9 +262,12 @@ static int csum_tree_block(struct extent_buffer *buf, u8 *result)
unsigned long map_start;
unsigned long map_len;
int err;
- u32 crc = ~(u32)0;
+
+ shash->tfm = fs_info->csum_shash;
+ crypto_shash_init(shash);
len = buf->len - offset;
+
while (len > 0) {
/*
* Note: we don't need to check for the err == 1 case here, as
@@ -285,14 +280,13 @@ static int csum_tree_block(struct extent_buffer *buf, u8 *result)
if (WARN_ON(err))
return err;
cur_len = min(len, map_len - (offset - map_start));
- crc = btrfs_csum_data(kaddr + offset - map_start,
- crc, cur_len);
+ crypto_shash_update(shash, kaddr + offset - map_start, cur_len);
len -= cur_len;
offset += cur_len;
}
memset(result, 0, BTRFS_CSUM_SIZE);
- btrfs_csum_final(crc, result);
+ crypto_shash_final(shash, result);
return 0;
}
@@ -372,17 +366,20 @@ static int btrfs_check_super_csum(struct btrfs_fs_info *fs_info,
{
struct btrfs_super_block *disk_sb =
(struct btrfs_super_block *)raw_disk_sb;
- u32 crc = ~(u32)0;
char result[BTRFS_CSUM_SIZE];
+ SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
+
+ shash->tfm = fs_info->csum_shash;
+ crypto_shash_init(shash);
/*
* The super_block structure does not span the whole
* BTRFS_SUPER_INFO_SIZE range, we expect that the unused space is
* filled with zeros and is included in the checksum.
*/
- crc = btrfs_csum_data(raw_disk_sb + BTRFS_CSUM_SIZE,
- crc, BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE);
- btrfs_csum_final(crc, result);
+ crypto_shash_update(shash, raw_disk_sb + BTRFS_CSUM_SIZE,
+ BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE);
+ crypto_shash_final(shash, result);
if (memcmp(disk_sb->csum, result, btrfs_super_csum_size(disk_sb)))
return 1;
@@ -3512,17 +3509,20 @@ struct buffer_head *btrfs_read_dev_super(struct block_device *bdev)
static int write_dev_supers(struct btrfs_device *device,
struct btrfs_super_block *sb, int max_mirrors)
{
+ struct btrfs_fs_info *fs_info = device->fs_info;
+ SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
struct buffer_head *bh;
int i;
int ret;
int errors = 0;
- u32 crc;
u64 bytenr;
int op_flags;
if (max_mirrors == 0)
max_mirrors = BTRFS_SUPER_MIRROR_MAX;
+ shash->tfm = fs_info->csum_shash;
+
for (i = 0; i < max_mirrors; i++) {
bytenr = btrfs_sb_offset(i);
if (bytenr + BTRFS_SUPER_INFO_SIZE >=
@@ -3531,10 +3531,10 @@ static int write_dev_supers(struct btrfs_device *device,
btrfs_set_super_bytenr(sb, bytenr);
- crc = ~(u32)0;
- crc = btrfs_csum_data((const char *)sb + BTRFS_CSUM_SIZE, crc,
- BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE);
- btrfs_csum_final(crc, sb->csum);
+ crypto_shash_init(shash);
+ crypto_shash_update(shash, (const char *)sb + BTRFS_CSUM_SIZE,
+ BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE);
+ crypto_shash_final(shash, sb->csum);
/* One reference for us, and we leave it for the caller */
bh = __getblk(device->bdev, bytenr / BTRFS_BDEV_BLOCKSIZE,