summaryrefslogtreecommitdiff
path: root/block/t10-pi.c
diff options
context:
space:
mode:
authorMax Gurtovoy <maxg@mellanox.com>2018-07-30 00:15:32 +0300
committerJens Axboe <axboe@kernel.dk>2018-07-30 17:27:02 +0300
commit10c41ddd61323b27b447bc8e18296ac6c06107ad (patch)
tree116e298295cfafda21080e0c83b501862753fcf1 /block/t10-pi.c
parentddd0bc756983dc4d19000a4fe021b4c7f9d59aab (diff)
downloadlinux-10c41ddd61323b27b447bc8e18296ac6c06107ad.tar.xz
block: move dif_prepare/dif_complete functions to block layer
Currently these functions are implemented in the scsi layer, but their actual place should be the block layer since T10-PI is a general data integrity feature that is used in the nvme protocol as well. Also, use the tuple size from the integrity profile since it may vary between integrity types. Suggested-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Max Gurtovoy <maxg@mellanox.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'block/t10-pi.c')
-rw-r--r--block/t10-pi.c110
1 files changed, 110 insertions, 0 deletions
diff --git a/block/t10-pi.c b/block/t10-pi.c
index a98db384048f..62aed77d0bb9 100644
--- a/block/t10-pi.c
+++ b/block/t10-pi.c
@@ -184,3 +184,113 @@ const struct blk_integrity_profile t10_pi_type3_ip = {
.verify_fn = t10_pi_type3_verify_ip,
};
EXPORT_SYMBOL(t10_pi_type3_ip);
+
+/**
+ * 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);