linux-imx

​

/**

 * t10_pi_prepare - prepare PI prior submitting request to device

 * @rq:              request with PI that should be prepared

 * @protection_type: PI type (Type 1/Type 2/Type 3)

 *

 * 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.

 *

 * Type 3 does not have a reference tag so no remapping is required.

 */

void t10_pi_prepare(struct request *rq, u8 protection_type)

{

    const int tuple_sz = rq->q->integrity.tuple_size;

    u32 ref_tag = t10_pi_ref_tag(rq);

    struct bio *bio;

​

    if (protection_type == T10_PI_TYPE3_PROTECTION)

        return;

​

    __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) {

            void *p, *pmap;

            unsigned int j;

​

            pmap = kmap_atomic(iv.bv_page);

            p = pmap + iv.bv_offset;

            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_atomic(pmap);

        }

​

        bip->bip_flags |= BIP_MAPPED_INTEGRITY;

    }

}

EXPORT_SYMBOL(t10_pi_prepare);

​

/**

 * t10_pi_complete - prepare PI prior returning request to the block layer

 * @rq:              request with PI that should be prepared

 * @protection_type: PI type (Type 1/Type 2/Type 3)

 * @intervals:       total elements 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.

 *

 * Type 3 does not have a reference tag so no remapping is required.

 */

void t10_pi_complete(struct request *rq, u8 protection_type,

             unsigned int intervals)

{

    const int tuple_sz = rq->q->integrity.tuple_size;

    u32 ref_tag = t10_pi_ref_tag(rq);

    struct bio *bio;

​

    if (protection_type == T10_PI_TYPE3_PROTECTION)

        return;

​

    __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) {

            void *p, *pmap;

            unsigned int j;

​

            pmap = kmap_atomic(iv.bv_page);

            p = pmap + iv.bv_offset;

            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_atomic(pmap);

        }

    }

}

EXPORT_SYMBOL(t10_pi_complete);