Commit d5178578 authored by Johannes Thumshirn's avatar Johannes Thumshirn Committed by David Sterba
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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: default avatarJohannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: default avatarDavid Sterba <dsterba@suse.com>
Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent 6d97c6e3
......@@ -2,7 +2,8 @@
config BTRFS_FS
tristate "Btrfs filesystem support"
select LIBCRC32C
select CRYPTO
select CRYPTO_CRC32C
select ZLIB_INFLATE
select ZLIB_DEFLATE
select LZO_COMPRESS
......
......@@ -83,7 +83,7 @@
#include <linux/blkdev.h>
#include <linux/mm.h>
#include <linux/string.h>
#include <linux/crc32c.h>
#include <crypto/hash.h>
#include "ctree.h"
#include "disk-io.h"
#include "transaction.h"
......@@ -1710,9 +1710,9 @@ static int btrfsic_test_for_metadata(struct btrfsic_state *state,
char **datav, unsigned int num_pages)
{
struct btrfs_fs_info *fs_info = state->fs_info;
SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
struct btrfs_header *h;
u8 csum[BTRFS_CSUM_SIZE];
u32 crc = ~(u32)0;
unsigned int i;
if (num_pages * PAGE_SIZE < state->metablock_size)
......@@ -1723,14 +1723,17 @@ static int btrfsic_test_for_metadata(struct btrfsic_state *state,
if (memcmp(h->fsid, fs_info->fs_devices->fsid, BTRFS_FSID_SIZE))
return 1;
shash->tfm = fs_info->csum_shash;
crypto_shash_init(shash);
for (i = 0; i < num_pages; i++) {
u8 *data = i ? datav[i] : (datav[i] + BTRFS_CSUM_SIZE);
size_t sublen = i ? PAGE_SIZE :
(PAGE_SIZE - BTRFS_CSUM_SIZE);
crc = btrfs_csum_data(data, crc, sublen);
crypto_shash_update(shash, data, sublen);
}
btrfs_csum_final(crc, csum);
crypto_shash_final(shash, csum);
if (memcmp(csum, h->csum, state->csum_size))
return 1;
......
......@@ -17,6 +17,7 @@
#include <linux/slab.h>
#include <linux/sched/mm.h>
#include <linux/log2.h>
#include <crypto/hash.h>
#include "ctree.h"
#include "disk-io.h"
#include "transaction.h"
......@@ -58,29 +59,33 @@ static int check_compressed_csum(struct btrfs_inode *inode,
u64 disk_start)
{
struct btrfs_fs_info *fs_info = inode->root->fs_info;
SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
const u16 csum_size = btrfs_super_csum_size(fs_info->super_copy);
int ret;
struct page *page;
unsigned long i;
char *kaddr;
u32 csum;
u8 csum[BTRFS_CSUM_SIZE];
u8 *cb_sum = cb->sums;
if (inode->flags & BTRFS_INODE_NODATASUM)
return 0;
shash->tfm = fs_info->csum_shash;
for (i = 0; i < cb->nr_pages; i++) {
page = cb->compressed_pages[i];
csum = ~(u32)0;
crypto_shash_init(shash);
kaddr = kmap_atomic(page);
csum = btrfs_csum_data(kaddr, csum, PAGE_SIZE);
btrfs_csum_final(csum, (u8 *)&csum);
crypto_shash_update(shash, kaddr, PAGE_SIZE);
kunmap_atomic(kaddr);
crypto_shash_final(shash, (u8 *)&csum);
if (memcmp(&csum, cb_sum, csum_size)) {
btrfs_print_data_csum_error(inode, disk_start, csum,
*(u32 *)cb_sum, cb->mirror_num);
btrfs_print_data_csum_error(inode, disk_start,
*(u32 *)csum, *(u32 *)cb_sum,
cb->mirror_num);
ret = -EIO;
goto fail;
}
......
......@@ -246,16 +246,6 @@ out:
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,
......
......@@ -115,8 +115,6 @@ int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid,
int atomic);
int btrfs_read_buffer(struct extent_buffer *buf, u64 parent_transid, int level,
struct btrfs_key *first_key);
u32 btrfs_csum_data(const char *data, u32 seed, size_t len);
void btrfs_csum_final(u32 crc, u8 *result);
blk_status_t btrfs_bio_wq_end_io(struct btrfs_fs_info *info, struct bio *bio,
enum btrfs_wq_endio_type metadata);
blk_status_t btrfs_wq_submit_bio(struct btrfs_fs_info *fs_info, struct bio *bio,
......
......@@ -8,6 +8,7 @@
#include <linux/pagemap.h>
#include <linux/highmem.h>
#include <linux/sched/mm.h>
#include <crypto/hash.h>
#include "ctree.h"
#include "disk-io.h"
#include "transaction.h"
......@@ -432,6 +433,7 @@ blk_status_t btrfs_csum_one_bio(struct inode *inode, struct bio *bio,
u64 file_start, int contig)
{
struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
struct btrfs_ordered_sum *sums;
struct btrfs_ordered_extent *ordered = NULL;
char *data;
......@@ -465,6 +467,8 @@ blk_status_t btrfs_csum_one_bio(struct inode *inode, struct bio *bio,
sums->bytenr = (u64)bio->bi_iter.bi_sector << 9;
index = 0;
shash->tfm = fs_info->csum_shash;
bio_for_each_segment(bvec, bio, iter) {
if (!contig)
offset = page_offset(bvec.bv_page) + bvec.bv_offset;
......@@ -479,8 +483,6 @@ blk_status_t btrfs_csum_one_bio(struct inode *inode, struct bio *bio,
- 1);
for (i = 0; i < nr_sectors; i++) {
u32 tmp;
if (offset >= ordered->file_offset + ordered->len ||
offset < ordered->file_offset) {
unsigned long bytes_left;
......@@ -506,15 +508,13 @@ blk_status_t btrfs_csum_one_bio(struct inode *inode, struct bio *bio,
index = 0;
}
memset(&sums->sums[index], 0xff, csum_size);
crypto_shash_init(shash);
data = kmap_atomic(bvec.bv_page);
tmp = btrfs_csum_data(data + bvec.bv_offset
+ (i * fs_info->sectorsize),
*(u32 *)&sums->sums[index],
fs_info->sectorsize);
crypto_shash_update(shash, data + bvec.bv_offset
+ (i * fs_info->sectorsize),
fs_info->sectorsize);
kunmap_atomic(data);
btrfs_csum_final(tmp,
(char *)(sums->sums + index));
crypto_shash_final(shash, (char *)(sums->sums + index));
index += csum_size;
offset += fs_info->sectorsize;
this_sum_bytes += fs_info->sectorsize;
......
......@@ -3203,23 +3203,30 @@ static int __readpage_endio_check(struct inode *inode,
int icsum, struct page *page,
int pgoff, u64 start, size_t len)
{
struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
char *kaddr;
u32 csum_expected;
u32 csum = ~(u32)0;
u16 csum_size = btrfs_super_csum_size(fs_info->super_copy);
u8 *csum_expected;
u8 csum[BTRFS_CSUM_SIZE];
csum_expected = *(((u32 *)io_bio->csum) + icsum);
csum_expected = ((u8 *)io_bio->csum) + icsum * csum_size;
kaddr = kmap_atomic(page);
csum = btrfs_csum_data(kaddr + pgoff, csum, len);
btrfs_csum_final(csum, (u8 *)&csum);
if (csum != csum_expected)
shash->tfm = fs_info->csum_shash;
crypto_shash_init(shash);
crypto_shash_update(shash, kaddr + pgoff, len);
crypto_shash_final(shash, csum);
if (memcmp(csum, csum_expected, csum_size))
goto zeroit;
kunmap_atomic(kaddr);
return 0;
zeroit:
btrfs_print_data_csum_error(BTRFS_I(inode), start, csum, csum_expected,
io_bio->mirror_num);
btrfs_print_data_csum_error(BTRFS_I(inode), start, *(u32 *)csum,
*(u32 *)csum_expected, io_bio->mirror_num);
memset(kaddr + pgoff, 1, len);
flush_dcache_page(page);
kunmap_atomic(kaddr);
......
......@@ -6,6 +6,7 @@
#include <linux/blkdev.h>
#include <linux/ratelimit.h>
#include <linux/sched/mm.h>
#include <crypto/hash.h>
#include "ctree.h"
#include "volumes.h"
#include "disk-io.h"
......@@ -1787,11 +1788,12 @@ static int scrub_checksum(struct scrub_block *sblock)
static int scrub_checksum_data(struct scrub_block *sblock)
{
struct scrub_ctx *sctx = sblock->sctx;
struct btrfs_fs_info *fs_info = sctx->fs_info;
SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
u8 csum[BTRFS_CSUM_SIZE];
u8 *on_disk_csum;
struct page *page;
void *buffer;
u32 crc = ~(u32)0;
u64 len;
int index;
......@@ -1799,6 +1801,9 @@ static int scrub_checksum_data(struct scrub_block *sblock)
if (!sblock->pagev[0]->have_csum)
return 0;
shash->tfm = fs_info->csum_shash;
crypto_shash_init(shash);
on_disk_csum = sblock->pagev[0]->csum;
page = sblock->pagev[0]->page;
buffer = kmap_atomic(page);
......@@ -1808,7 +1813,7 @@ static int scrub_checksum_data(struct scrub_block *sblock)
for (;;) {
u64 l = min_t(u64, len, PAGE_SIZE);
crc = btrfs_csum_data(buffer, crc, l);
crypto_shash_update(shash, buffer, l);
kunmap_atomic(buffer);
len -= l;
if (len == 0)
......@@ -1820,7 +1825,7 @@ static int scrub_checksum_data(struct scrub_block *sblock)
buffer = kmap_atomic(page);
}
btrfs_csum_final(crc, csum);
crypto_shash_final(shash, csum);
if (memcmp(csum, on_disk_csum, sctx->csum_size))
sblock->checksum_error = 1;
......@@ -1832,16 +1837,19 @@ static int scrub_checksum_tree_block(struct scrub_block *sblock)
struct scrub_ctx *sctx = sblock->sctx;
struct btrfs_header *h;
struct btrfs_fs_info *fs_info = sctx->fs_info;
SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
u8 calculated_csum[BTRFS_CSUM_SIZE];
u8 on_disk_csum[BTRFS_CSUM_SIZE];
struct page *page;
void *mapped_buffer;
u64 mapped_size;
void *p;
u32 crc = ~(u32)0;
u64 len;
int index;
shash->tfm = fs_info->csum_shash;
crypto_shash_init(shash);
BUG_ON(sblock->page_count < 1);
page = sblock->pagev[0]->page;
mapped_buffer = kmap_atomic(page);
......@@ -1875,7 +1883,7 @@ static int scrub_checksum_tree_block(struct scrub_block *sblock)
for (;;) {
u64 l = min_t(u64, len, mapped_size);
crc = btrfs_csum_data(p, crc, l);
crypto_shash_update(shash, p, l);
kunmap_atomic(mapped_buffer);
len -= l;
if (len == 0)
......@@ -1889,7 +1897,7 @@ static int scrub_checksum_tree_block(struct scrub_block *sblock)
p = mapped_buffer;
}
btrfs_csum_final(crc, calculated_csum);
crypto_shash_final(shash, calculated_csum);
if (memcmp(calculated_csum, on_disk_csum, sctx->csum_size))
sblock->checksum_error = 1;
......@@ -1900,18 +1908,22 @@ static int scrub_checksum_super(struct scrub_block *sblock)
{
struct btrfs_super_block *s;
struct scrub_ctx *sctx = sblock->sctx;
struct btrfs_fs_info *fs_info = sctx->fs_info;
SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
u8 calculated_csum[BTRFS_CSUM_SIZE];
u8 on_disk_csum[BTRFS_CSUM_SIZE];
struct page *page;
void *mapped_buffer;
u64 mapped_size;
void *p;
u32 crc = ~(u32)0;
int fail_gen = 0;
int fail_cor = 0;
u64 len;
int index;
shash->tfm = fs_info->csum_shash;
crypto_shash_init(shash);
BUG_ON(sblock->page_count < 1);
page = sblock->pagev[0]->page;
mapped_buffer = kmap_atomic(page);
......@@ -1934,7 +1946,7 @@ static int scrub_checksum_super(struct scrub_block *sblock)
for (;;) {
u64 l = min_t(u64, len, mapped_size);
crc = btrfs_csum_data(p, crc, l);
crypto_shash_update(shash, p, l);
kunmap_atomic(mapped_buffer);
len -= l;
if (len == 0)
......@@ -1948,7 +1960,7 @@ static int scrub_checksum_super(struct scrub_block *sblock)
p = mapped_buffer;
}
btrfs_csum_final(crc, calculated_csum);
crypto_shash_final(shash, calculated_csum);
if (memcmp(calculated_csum, on_disk_csum, sctx->csum_size))
++fail_cor;
......
......@@ -2464,3 +2464,4 @@ late_initcall(init_btrfs_fs);
module_exit(exit_btrfs_fs)
MODULE_LICENSE("GPL");
MODULE_SOFTDEP("pre: crc32c");
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