On 26.08.19 г. 14:48 ч., Johannes Thumshirn wrote:
> From: David Sterba <dsterba@xxxxxxxx>
>
> Add xxhash64 as another checksumming algorithm.
>
> Signed-off-by: David Sterba <dsterba@xxxxxxxx>
> Signed-off-by: Johannes Thumshirn <jthumshirn@xxxxxxx>
> ---
> Makefile | 3 ++-
> cmds/inspect-dump-super.c | 25 ++++++++++++++++---------
> convert/common.c | 2 +-
> convert/main.c | 2 +-
> crypto/hash.c | 16 ++++++++++++++++
> crypto/hash.h | 10 ++++++++++
> crypto/xxhash.c | 2 +-
> ctree.h | 18 +++++++++++++-----
> disk-io.c | 7 +++++--
> image/main.c | 5 +++--
> mkfs/common.c | 14 +++++++-------
> mkfs/main.c | 6 +++++-
> 12 files changed, 80 insertions(+), 30 deletions(-)
> create mode 100644 crypto/hash.c
> create mode 100644 crypto/hash.h
>
> diff --git a/Makefile b/Makefile
> index 82417d19a9f8..1982e6f5d70e 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -151,7 +151,8 @@ cmds_objects = cmds/subvolume.o cmds/filesystem.o cmds/device.o cmds/scrub.o \
> mkfs/common.o check/mode-common.o check/mode-lowmem.o
> libbtrfs_objects = send-stream.o send-utils.o kernel-lib/rbtree.o btrfs-list.o \
> kernel-lib/crc32c.o common/messages.o \
> - uuid-tree.o utils-lib.o common/rbtree-utils.o
> + uuid-tree.o utils-lib.o common/rbtree-utils.o \
> + crypto/hash.o crypto/xxhash.o
> libbtrfs_headers = send-stream.h send-utils.h send.h kernel-lib/rbtree.h btrfs-list.h \
> kernel-lib/crc32c.h kernel-lib/list.h kerncompat.h \
> kernel-lib/radix-tree.h kernel-lib/sizes.h kernel-lib/raid56.h \
> diff --git a/cmds/inspect-dump-super.c b/cmds/inspect-dump-super.c
> index 58bf82b0bbd3..1001c8aa5c85 100644
> --- a/cmds/inspect-dump-super.c
> +++ b/cmds/inspect-dump-super.c
> @@ -311,6 +311,17 @@ static void print_readable_super_flag(u64 flag)
> super_flags_num, BTRFS_SUPER_FLAG_SUPP);
> }
>
> +static bool is_valid_csum_type(u16 csum_type)
> +{
> + switch (csum_type) {
> + case BTRFS_CSUM_TYPE_CRC32:
> + case BTRFS_CSUM_TYPE_XXHASH:
> + return true;
> + default:
> + return false;
> + }
> +}
> +
> static void dump_superblock(struct btrfs_super_block *sb, int full)
> {
> int i;
> @@ -326,15 +337,11 @@ static void dump_superblock(struct btrfs_super_block *sb, int full)
> csum_type = btrfs_super_csum_type(sb);
> csum_size = BTRFS_CSUM_SIZE;
> printf("csum_type\t\t%hu (", csum_type);
> - if (csum_type >= ARRAY_SIZE(btrfs_csum_sizes)) {
> + if (csum_type >= ARRAY_SIZE(btrfs_csums)) {
Why not is_valid_csum_type ?
> printf("INVALID");
> } else {
> - if (csum_type == BTRFS_CSUM_TYPE_CRC32) {
> - printf("crc32c");
> - csum_size = btrfs_csum_sizes[csum_type];
> - } else {
> - printf("unknown");
> - }
> + printf("%s", btrfs_csums[csum_type].name);
> + csum_size = btrfs_csums[csum_type].size;
> }
> printf(")\n");
> printf("csum_size\t\t%llu\n", (unsigned long long)csum_size);
> @@ -342,8 +349,8 @@ static void dump_superblock(struct btrfs_super_block *sb, int full)
> printf("csum\t\t\t0x");
> for (i = 0, p = sb->csum; i < csum_size; i++)
> printf("%02x", p[i]);
> - if (csum_type != BTRFS_CSUM_TYPE_CRC32 ||
> - csum_size != btrfs_csum_sizes[BTRFS_CSUM_TYPE_CRC32])
> + if (!is_valid_csum_type(csum_type) ||
> + csum_size != btrfs_csums[csum_type].size)
That second check - can it ever trigger? If the csum_type >= ARRAY_SIZE
goes into the else branch then csum_size == btrfs_csums[csum_type].size
so this check is guaranteed to never fail. OTOH, if we print invalid
above then csum_type is guaranteed to be above ARRAY_SIZE(btrfs_csums)
and I thin this guarantees that !is_valid_csum_type(csum_type) is going
to be true e.g. we will print UNKNOWN CSUM type. So I guess a simple
'if (!is_valid_csum_type(csum_type)' will suffice here?
> printf(" [UNKNOWN CSUM TYPE OR SIZE]");
> else if (check_csum_sblock(sb, csum_size, csum_type))
> printf(" [match]");
> diff --git a/convert/common.c b/convert/common.c
> index 8f5fdbf507a4..e479d70f4e9e 100644
> --- a/convert/common.c
> +++ b/convert/common.c
> @@ -223,7 +223,7 @@ static inline int write_temp_extent_buffer(int fd, struct extent_buffer *buf,
> {
> int ret;
>
> - csum_tree_block_size(buf, btrfs_csum_sizes[cfg->csum_type], 0,
> + csum_tree_block_size(buf, btrfs_csums[cfg->csum_type].size, 0,
> cfg->csum_type);
>
> /* Temporary extent buffer is always mapped 1:1 on disk */
> diff --git a/convert/main.c b/convert/main.c
> index 5e6b12431f59..5eb2a59fb68a 100644
> --- a/convert/main.c
> +++ b/convert/main.c
> @@ -1058,7 +1058,7 @@ static int migrate_super_block(int fd, u64 old_bytenr)
> BUG_ON(btrfs_super_bytenr(super) != old_bytenr);
> btrfs_set_super_bytenr(super, BTRFS_SUPER_INFO_OFFSET);
>
> - csum_tree_block_size(buf, btrfs_csum_sizes[BTRFS_CSUM_TYPE_CRC32], 0,
> + csum_tree_block_size(buf, btrfs_csums[BTRFS_CSUM_TYPE_CRC32].size, 0,
> btrfs_super_csum_type(super));
> ret = pwrite(fd, buf->data, BTRFS_SUPER_INFO_SIZE,
> BTRFS_SUPER_INFO_OFFSET);
> diff --git a/crypto/hash.c b/crypto/hash.c
> new file mode 100644
> index 000000000000..fda7fc4e9f23
> --- /dev/null
> +++ b/crypto/hash.c
> @@ -0,0 +1,16 @@
> +#include "crypto/hash.h"
> +#include "crypto/xxhash.h"
> +
> +int hash_xxhash(const u8 *buf, size_t length, u8 *out)
> +{
> + XXH64_hash_t hash;
> +
> + hash = XXH64(buf, length, 0);
> + /* NOTE: we're not taking the canonical form here but the plain hash to
> + * be compatible with the kernel implementation!
> + */
> + memcpy(out, &hash, 8);
> +
> + return 0;
> +}
> +
> diff --git a/crypto/hash.h b/crypto/hash.h
> new file mode 100644
> index 000000000000..45c1ef17bc57
> --- /dev/null
> +++ b/crypto/hash.h
> @@ -0,0 +1,10 @@
> +#ifndef CRYPTO_HASH_H
> +#define CRYPTO_HASH_H
> +
> +#include "../kerncompat.h"
> +
> +#define CRYPTO_HASH_SIZE_MAX 32
> +
> +int hash_xxhash(const u8 *buf, size_t length, u8 *out);
> +
> +#endif
> diff --git a/crypto/xxhash.c b/crypto/xxhash.c
> index af9d02795ac6..7f381c8b56a0 100644
> --- a/crypto/xxhash.c
> +++ b/crypto/xxhash.c
> @@ -1018,7 +1018,7 @@ XXH_PUBLIC_API XXH64_hash_t XXH64_hashFromCanonical(const XXH64_canonical_t* src
> * New generation hash designed for speed on small keys and vectorization
> ************************************************************************ */
>
> -#include "xxh3.h"
> +/* #include "xxh3.h" */
Does that mean progs compilation is broken by the previous patch since
it includes a file which cannot be found?
>
>
> #endif /* XXH_NO_LONG_LONG */
<snip>
> diff --git a/mkfs/main.c b/mkfs/main.c
> index 075e7e331ab4..c78481da50c2 100644
> --- a/mkfs/main.c
> +++ b/mkfs/main.c
> @@ -385,6 +385,9 @@ static enum btrfs_csum_type parse_csum_type(const char *s)
> {
> if (strcasecmp(s, "crc32c") == 0) {
> return BTRFS_CSUM_TYPE_CRC32;
> + } else if (strcasecmp(s, "xxhash64") == 0 ||
> + strcasecmp(s, "xxhash") == 0) {
Don't we want to be very explicit about only supporting xxhash64, and
not aliasing xxhash to mean xxhash64? I.e remove the xxhash comparison
and consider it invalid.
> + return BTRFS_CSUM_TYPE_XXHASH;
> } else {
> error("unknown csum type %s", s);
> exit(1);
> @@ -1370,7 +1373,8 @@ raid_groups:
> pretty_size(allocation.system));
> printf("SSD detected: %s\n", ssd ? "yes" : "no");
> btrfs_parse_features_to_string(features_buf, features);
> - printf("Incompat features: %s", features_buf);
> + printf("Incompat features: %s\n", features_buf);
> + printf("Checksum: %s", btrfs_csums[csum_type].name);
> printf("\n");
>
> list_all_devices(root);
>
