diff options
Diffstat (limited to '')
-rw-r--r-- | block/t10-pi.c | 475 |
1 files changed, 475 insertions, 0 deletions
diff --git a/block/t10-pi.c b/block/t10-pi.c new file mode 100644 index 0000000000..914d8cddd4 --- /dev/null +++ b/block/t10-pi.c @@ -0,0 +1,475 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * t10_pi.c - Functions for generating and verifying T10 Protection + * Information. + */ + +#include <linux/t10-pi.h> +#include <linux/blk-integrity.h> +#include <linux/crc-t10dif.h> +#include <linux/crc64.h> +#include <linux/module.h> +#include <net/checksum.h> +#include <asm/unaligned.h> + +typedef __be16 (csum_fn) (void *, unsigned int); + +static __be16 t10_pi_crc_fn(void *data, unsigned int len) +{ + return cpu_to_be16(crc_t10dif(data, len)); +} + +static __be16 t10_pi_ip_fn(void *data, unsigned int len) +{ + return (__force __be16)ip_compute_csum(data, len); +} + +/* + * Type 1 and Type 2 protection use the same format: 16 bit guard tag, + * 16 bit app tag, 32 bit reference tag. Type 3 does not define the ref + * tag. + */ +static blk_status_t t10_pi_generate(struct blk_integrity_iter *iter, + csum_fn *fn, enum t10_dif_type type) +{ + unsigned int i; + + for (i = 0 ; i < iter->data_size ; i += iter->interval) { + struct t10_pi_tuple *pi = iter->prot_buf; + + pi->guard_tag = fn(iter->data_buf, iter->interval); + pi->app_tag = 0; + + if (type == T10_PI_TYPE1_PROTECTION) + pi->ref_tag = cpu_to_be32(lower_32_bits(iter->seed)); + else + pi->ref_tag = 0; + + iter->data_buf += iter->interval; + iter->prot_buf += iter->tuple_size; + iter->seed++; + } + + return BLK_STS_OK; +} + +static blk_status_t t10_pi_verify(struct blk_integrity_iter *iter, + csum_fn *fn, enum t10_dif_type type) +{ + unsigned int i; + + BUG_ON(type == T10_PI_TYPE0_PROTECTION); + + for (i = 0 ; i < iter->data_size ; i += iter->interval) { + struct t10_pi_tuple *pi = iter->prot_buf; + __be16 csum; + + if (type == T10_PI_TYPE1_PROTECTION || + type == T10_PI_TYPE2_PROTECTION) { + if (pi->app_tag == T10_PI_APP_ESCAPE) + goto next; + + if (be32_to_cpu(pi->ref_tag) != + lower_32_bits(iter->seed)) { + pr_err("%s: ref tag error at location %llu " \ + "(rcvd %u)\n", iter->disk_name, + (unsigned long long) + iter->seed, be32_to_cpu(pi->ref_tag)); + return BLK_STS_PROTECTION; + } + } else if (type == T10_PI_TYPE3_PROTECTION) { + if (pi->app_tag == T10_PI_APP_ESCAPE && + pi->ref_tag == T10_PI_REF_ESCAPE) + goto next; + } + + csum = fn(iter->data_buf, iter->interval); + + if (pi->guard_tag != csum) { + pr_err("%s: guard tag error at sector %llu " \ + "(rcvd %04x, want %04x)\n", iter->disk_name, + (unsigned long long)iter->seed, + be16_to_cpu(pi->guard_tag), be16_to_cpu(csum)); + return BLK_STS_PROTECTION; + } + +next: + iter->data_buf += iter->interval; + iter->prot_buf += iter->tuple_size; + iter->seed++; + } + + return BLK_STS_OK; +} + +static blk_status_t t10_pi_type1_generate_crc(struct blk_integrity_iter *iter) +{ + return t10_pi_generate(iter, t10_pi_crc_fn, T10_PI_TYPE1_PROTECTION); +} + +static blk_status_t t10_pi_type1_generate_ip(struct blk_integrity_iter *iter) +{ + return t10_pi_generate(iter, t10_pi_ip_fn, T10_PI_TYPE1_PROTECTION); +} + +static blk_status_t t10_pi_type1_verify_crc(struct blk_integrity_iter *iter) +{ + return t10_pi_verify(iter, t10_pi_crc_fn, T10_PI_TYPE1_PROTECTION); +} + +static blk_status_t t10_pi_type1_verify_ip(struct blk_integrity_iter *iter) +{ + return t10_pi_verify(iter, t10_pi_ip_fn, T10_PI_TYPE1_PROTECTION); +} + +/** + * t10_pi_type1_prepare - prepare PI prior submitting request to device + * @rq: request with PI that should be prepared + * + * For Type 1/Type 2, the virtual start sector is the one that was + * originally submitted by the block layer for the ref_tag usage. Due to + * partitioning, MD/DM cloning, etc. the actual physical start sector is + * likely to be different. Remap protection information to match the + * physical LBA. + */ +static void t10_pi_type1_prepare(struct request *rq) +{ + const int tuple_sz = rq->q->integrity.tuple_size; + u32 ref_tag = t10_pi_ref_tag(rq); + struct bio *bio; + + __rq_for_each_bio(bio, rq) { + struct bio_integrity_payload *bip = bio_integrity(bio); + u32 virt = bip_get_seed(bip) & 0xffffffff; + struct bio_vec iv; + struct bvec_iter iter; + + /* Already remapped? */ + if (bip->bip_flags & BIP_MAPPED_INTEGRITY) + break; + + bip_for_each_vec(iv, bip, iter) { + unsigned int j; + void *p; + + p = bvec_kmap_local(&iv); + for (j = 0; j < iv.bv_len; j += tuple_sz) { + struct t10_pi_tuple *pi = p; + + if (be32_to_cpu(pi->ref_tag) == virt) + pi->ref_tag = cpu_to_be32(ref_tag); + virt++; + ref_tag++; + p += tuple_sz; + } + kunmap_local(p); + } + + bip->bip_flags |= BIP_MAPPED_INTEGRITY; + } +} + +/** + * t10_pi_type1_complete - prepare PI prior returning request to the blk layer + * @rq: request with PI that should be prepared + * @nr_bytes: total bytes to prepare + * + * For Type 1/Type 2, the virtual start sector is the one that was + * originally submitted by the block layer for the ref_tag usage. Due to + * partitioning, MD/DM cloning, etc. the actual physical start sector is + * likely to be different. Since the physical start sector was submitted + * to the device, we should remap it back to virtual values expected by the + * block layer. + */ +static void t10_pi_type1_complete(struct request *rq, unsigned int nr_bytes) +{ + unsigned intervals = nr_bytes >> rq->q->integrity.interval_exp; + const int tuple_sz = rq->q->integrity.tuple_size; + u32 ref_tag = t10_pi_ref_tag(rq); + struct bio *bio; + + __rq_for_each_bio(bio, rq) { + struct bio_integrity_payload *bip = bio_integrity(bio); + u32 virt = bip_get_seed(bip) & 0xffffffff; + struct bio_vec iv; + struct bvec_iter iter; + + bip_for_each_vec(iv, bip, iter) { + unsigned int j; + void *p; + + p = bvec_kmap_local(&iv); + for (j = 0; j < iv.bv_len && intervals; j += tuple_sz) { + struct t10_pi_tuple *pi = p; + + if (be32_to_cpu(pi->ref_tag) == ref_tag) + pi->ref_tag = cpu_to_be32(virt); + virt++; + ref_tag++; + intervals--; + p += tuple_sz; + } + kunmap_local(p); + } + } +} + +static blk_status_t t10_pi_type3_generate_crc(struct blk_integrity_iter *iter) +{ + return t10_pi_generate(iter, t10_pi_crc_fn, T10_PI_TYPE3_PROTECTION); +} + +static blk_status_t t10_pi_type3_generate_ip(struct blk_integrity_iter *iter) +{ + return t10_pi_generate(iter, t10_pi_ip_fn, T10_PI_TYPE3_PROTECTION); +} + +static blk_status_t t10_pi_type3_verify_crc(struct blk_integrity_iter *iter) +{ + return t10_pi_verify(iter, t10_pi_crc_fn, T10_PI_TYPE3_PROTECTION); +} + +static blk_status_t t10_pi_type3_verify_ip(struct blk_integrity_iter *iter) +{ + return t10_pi_verify(iter, t10_pi_ip_fn, T10_PI_TYPE3_PROTECTION); +} + +/* Type 3 does not have a reference tag so no remapping is required. */ +static void t10_pi_type3_prepare(struct request *rq) +{ +} + +/* Type 3 does not have a reference tag so no remapping is required. */ +static void t10_pi_type3_complete(struct request *rq, unsigned int nr_bytes) +{ +} + +const struct blk_integrity_profile t10_pi_type1_crc = { + .name = "T10-DIF-TYPE1-CRC", + .generate_fn = t10_pi_type1_generate_crc, + .verify_fn = t10_pi_type1_verify_crc, + .prepare_fn = t10_pi_type1_prepare, + .complete_fn = t10_pi_type1_complete, +}; +EXPORT_SYMBOL(t10_pi_type1_crc); + +const struct blk_integrity_profile t10_pi_type1_ip = { + .name = "T10-DIF-TYPE1-IP", + .generate_fn = t10_pi_type1_generate_ip, + .verify_fn = t10_pi_type1_verify_ip, + .prepare_fn = t10_pi_type1_prepare, + .complete_fn = t10_pi_type1_complete, +}; +EXPORT_SYMBOL(t10_pi_type1_ip); + +const struct blk_integrity_profile t10_pi_type3_crc = { + .name = "T10-DIF-TYPE3-CRC", + .generate_fn = t10_pi_type3_generate_crc, + .verify_fn = t10_pi_type3_verify_crc, + .prepare_fn = t10_pi_type3_prepare, + .complete_fn = t10_pi_type3_complete, +}; +EXPORT_SYMBOL(t10_pi_type3_crc); + +const struct blk_integrity_profile t10_pi_type3_ip = { + .name = "T10-DIF-TYPE3-IP", + .generate_fn = t10_pi_type3_generate_ip, + .verify_fn = t10_pi_type3_verify_ip, + .prepare_fn = t10_pi_type3_prepare, + .complete_fn = t10_pi_type3_complete, +}; +EXPORT_SYMBOL(t10_pi_type3_ip); + +static __be64 ext_pi_crc64(void *data, unsigned int len) +{ + return cpu_to_be64(crc64_rocksoft(data, len)); +} + +static blk_status_t ext_pi_crc64_generate(struct blk_integrity_iter *iter, + enum t10_dif_type type) +{ + unsigned int i; + + for (i = 0 ; i < iter->data_size ; i += iter->interval) { + struct crc64_pi_tuple *pi = iter->prot_buf; + + pi->guard_tag = ext_pi_crc64(iter->data_buf, iter->interval); + pi->app_tag = 0; + + if (type == T10_PI_TYPE1_PROTECTION) + put_unaligned_be48(iter->seed, pi->ref_tag); + else + put_unaligned_be48(0ULL, pi->ref_tag); + + iter->data_buf += iter->interval; + iter->prot_buf += iter->tuple_size; + iter->seed++; + } + + return BLK_STS_OK; +} + +static bool ext_pi_ref_escape(u8 *ref_tag) +{ + static u8 ref_escape[6] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff }; + + return memcmp(ref_tag, ref_escape, sizeof(ref_escape)) == 0; +} + +static blk_status_t ext_pi_crc64_verify(struct blk_integrity_iter *iter, + enum t10_dif_type type) +{ + unsigned int i; + + for (i = 0; i < iter->data_size; i += iter->interval) { + struct crc64_pi_tuple *pi = iter->prot_buf; + u64 ref, seed; + __be64 csum; + + if (type == T10_PI_TYPE1_PROTECTION) { + if (pi->app_tag == T10_PI_APP_ESCAPE) + goto next; + + ref = get_unaligned_be48(pi->ref_tag); + seed = lower_48_bits(iter->seed); + if (ref != seed) { + pr_err("%s: ref tag error at location %llu (rcvd %llu)\n", + iter->disk_name, seed, ref); + return BLK_STS_PROTECTION; + } + } else if (type == T10_PI_TYPE3_PROTECTION) { + if (pi->app_tag == T10_PI_APP_ESCAPE && + ext_pi_ref_escape(pi->ref_tag)) + goto next; + } + + csum = ext_pi_crc64(iter->data_buf, iter->interval); + if (pi->guard_tag != csum) { + pr_err("%s: guard tag error at sector %llu " \ + "(rcvd %016llx, want %016llx)\n", + iter->disk_name, (unsigned long long)iter->seed, + be64_to_cpu(pi->guard_tag), be64_to_cpu(csum)); + return BLK_STS_PROTECTION; + } + +next: + iter->data_buf += iter->interval; + iter->prot_buf += iter->tuple_size; + iter->seed++; + } + + return BLK_STS_OK; +} + +static blk_status_t ext_pi_type1_verify_crc64(struct blk_integrity_iter *iter) +{ + return ext_pi_crc64_verify(iter, T10_PI_TYPE1_PROTECTION); +} + +static blk_status_t ext_pi_type1_generate_crc64(struct blk_integrity_iter *iter) +{ + return ext_pi_crc64_generate(iter, T10_PI_TYPE1_PROTECTION); +} + +static void ext_pi_type1_prepare(struct request *rq) +{ + const int tuple_sz = rq->q->integrity.tuple_size; + u64 ref_tag = ext_pi_ref_tag(rq); + struct bio *bio; + + __rq_for_each_bio(bio, rq) { + struct bio_integrity_payload *bip = bio_integrity(bio); + u64 virt = lower_48_bits(bip_get_seed(bip)); + struct bio_vec iv; + struct bvec_iter iter; + + /* Already remapped? */ + if (bip->bip_flags & BIP_MAPPED_INTEGRITY) + break; + + bip_for_each_vec(iv, bip, iter) { + unsigned int j; + void *p; + + p = bvec_kmap_local(&iv); + for (j = 0; j < iv.bv_len; j += tuple_sz) { + struct crc64_pi_tuple *pi = p; + u64 ref = get_unaligned_be48(pi->ref_tag); + + if (ref == virt) + put_unaligned_be48(ref_tag, pi->ref_tag); + virt++; + ref_tag++; + p += tuple_sz; + } + kunmap_local(p); + } + + bip->bip_flags |= BIP_MAPPED_INTEGRITY; + } +} + +static void ext_pi_type1_complete(struct request *rq, unsigned int nr_bytes) +{ + unsigned intervals = nr_bytes >> rq->q->integrity.interval_exp; + const int tuple_sz = rq->q->integrity.tuple_size; + u64 ref_tag = ext_pi_ref_tag(rq); + struct bio *bio; + + __rq_for_each_bio(bio, rq) { + struct bio_integrity_payload *bip = bio_integrity(bio); + u64 virt = lower_48_bits(bip_get_seed(bip)); + struct bio_vec iv; + struct bvec_iter iter; + + bip_for_each_vec(iv, bip, iter) { + unsigned int j; + void *p; + + p = bvec_kmap_local(&iv); + for (j = 0; j < iv.bv_len && intervals; j += tuple_sz) { + struct crc64_pi_tuple *pi = p; + u64 ref = get_unaligned_be48(pi->ref_tag); + + if (ref == ref_tag) + put_unaligned_be48(virt, pi->ref_tag); + virt++; + ref_tag++; + intervals--; + p += tuple_sz; + } + kunmap_local(p); + } + } +} + +static blk_status_t ext_pi_type3_verify_crc64(struct blk_integrity_iter *iter) +{ + return ext_pi_crc64_verify(iter, T10_PI_TYPE3_PROTECTION); +} + +static blk_status_t ext_pi_type3_generate_crc64(struct blk_integrity_iter *iter) +{ + return ext_pi_crc64_generate(iter, T10_PI_TYPE3_PROTECTION); +} + +const struct blk_integrity_profile ext_pi_type1_crc64 = { + .name = "EXT-DIF-TYPE1-CRC64", + .generate_fn = ext_pi_type1_generate_crc64, + .verify_fn = ext_pi_type1_verify_crc64, + .prepare_fn = ext_pi_type1_prepare, + .complete_fn = ext_pi_type1_complete, +}; +EXPORT_SYMBOL_GPL(ext_pi_type1_crc64); + +const struct blk_integrity_profile ext_pi_type3_crc64 = { + .name = "EXT-DIF-TYPE3-CRC64", + .generate_fn = ext_pi_type3_generate_crc64, + .verify_fn = ext_pi_type3_verify_crc64, + .prepare_fn = t10_pi_type3_prepare, + .complete_fn = t10_pi_type3_complete, +}; +EXPORT_SYMBOL_GPL(ext_pi_type3_crc64); + +MODULE_LICENSE("GPL"); +MODULE_LICENSE("GPL"); |