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.
Suggested-by: Christoph Hellwig <hch@xxxxxx>
Cc: Jens Axboe <axboe@xxxxxxxxx>
Cc: Martin K. Petersen <martin.petersen@xxxxxxxxxx>
Signed-off-by: Max Gurtovoy <maxg@xxxxxxxxxxxx>
---
block/blk-integrity.c | 111 ++++++++++++++++++++++++++++++++++++++++++++++++
drivers/scsi/sd.c | 12 ++++--
drivers/scsi/sd.h | 9 ----
drivers/scsi/sd_dif.c | 113 -------------------------------------------------
include/linux/blkdev.h | 14 ++++++
5 files changed, 134 insertions(+), 125 deletions(-)
diff --git a/block/blk-integrity.c b/block/blk-integrity.c
index 6121611e1316..66b095a866d3 100644
--- a/block/blk-integrity.c
+++ b/block/blk-integrity.c
@@ -21,6 +21,7 @@
*/
#include <linux/blkdev.h>
+#include <linux/t10-pi.h>
#include <linux/backing-dev.h>
#include <linux/mempool.h>
#include <linux/bio.h>
@@ -451,3 +452,113 @@ void blk_integrity_del(struct gendisk *disk)
kobject_del(&disk->integrity_kobj);
kobject_put(&disk->integrity_kobj);
}
+
+/*
+ * The virtual start sector is the one that was originally submitted
+ * by the block layer. 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.
+ *
+ * From a protocol perspective there's a slight difference between
+ * Type 1 and 2. The latter uses command's 32-byte exclusively, and the
+ * reference tag is seeded in the command. This gives us the potential to
+ * avoid virt->phys remapping during write. However, at read time we
+ * don't know whether the virt sector is the same as when we wrote it
+ * (we could be reading from real disk as opposed to MD/DM device. So
+ * we always remap Type 2 making it identical to Type 1.
+ *
+ * Type 3 does not have a reference tag so no remapping is required.
+ */
+void blk_integrity_dif_prepare(struct request *rq, u8 protection_type,
+ u32 ref_tag)
+{
+ const int tuple_sz = sizeof(struct t10_pi_tuple);
+ struct bio *bio;
+ struct t10_pi_tuple *pi;
+ u32 phys, virt;
+
+ if (protection_type == T10_PI_TYPE3_PROTECTION)
+ return;
+
+ phys = ref_tag;
+
+ __rq_for_each_bio(bio, rq) {
+ struct bio_integrity_payload *bip = bio_integrity(bio);
+ struct bio_vec iv;
+ struct bvec_iter iter;
+ unsigned int j;
+
+ /* Already remapped? */
+ if (bip->bip_flags & BIP_MAPPED_INTEGRITY)
+ break;
+
+ virt = bip_get_seed(bip) & 0xffffffff;
+
+ bip_for_each_vec(iv, bip, iter) {
+ pi = kmap_atomic(iv.bv_page) + iv.bv_offset;
+
+ for (j = 0; j < iv.bv_len; j += tuple_sz, pi++) {
+
+ if (be32_to_cpu(pi->ref_tag) == virt)
+ pi->ref_tag = cpu_to_be32(phys);
+
+ virt++;
+ phys++;
+ }
+
+ kunmap_atomic(pi);
+ }
+
+ bip->bip_flags |= BIP_MAPPED_INTEGRITY;
+ }
+}
+EXPORT_SYMBOL(blk_integrity_dif_prepare);
+
+/*
+ * Remap physical sector values in the reference tag to the virtual
+ * values expected by the block layer.
+ */
+void blk_integrity_dif_complete(struct request *rq, u8 protection_type,
+ u32 ref_tag, unsigned int intervals)
+{
+ const int tuple_sz = sizeof(struct t10_pi_tuple);
+ struct bio *bio;
+ struct t10_pi_tuple *pi;
+ unsigned int j;
+ u32 phys, virt;
+
+ if (protection_type == T10_PI_TYPE3_PROTECTION)
+ return;
+
+ phys = ref_tag;
+
+ __rq_for_each_bio(bio, rq) {
+ struct bio_integrity_payload *bip = bio_integrity(bio);
+ struct bio_vec iv;
+ struct bvec_iter iter;
+
+ virt = bip_get_seed(bip) & 0xffffffff;
+
+ bip_for_each_vec(iv, bip, iter) {
+ pi = kmap_atomic(iv.bv_page) + iv.bv_offset;
+
+ for (j = 0; j < iv.bv_len; j += tuple_sz, pi++) {
+
+ if (intervals == 0) {
+ kunmap_atomic(pi);
+ return;
+ }
+
+ if (be32_to_cpu(pi->ref_tag) == phys)
+ pi->ref_tag = cpu_to_be32(virt);
+
+ virt++;
+ phys++;
+ intervals--;
+ }
+
+ kunmap_atomic(pi);
+ }
+ }
+}
+EXPORT_SYMBOL(blk_integrity_dif_complete);
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index 9421d9877730..4186bf027c59 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -1119,7 +1119,9 @@ static int sd_setup_read_write_cmnd(struct scsi_cmnd *SCpnt)
SCpnt->cmnd[0] = WRITE_6;
if (blk_integrity_rq(rq))
- sd_dif_prepare(SCpnt);
+ blk_integrity_dif_prepare(SCpnt->request,
+ sdkp->protection_type,
+ scsi_prot_ref_tag(SCpnt));
} else if (rq_data_dir(rq) == READ) {
SCpnt->cmnd[0] = READ_6;
@@ -2047,8 +2049,12 @@ static int sd_done(struct scsi_cmnd *SCpnt)
"sd_done: completed %d of %d bytes\n",
good_bytes, scsi_bufflen(SCpnt)));
- if (rq_data_dir(SCpnt->request) == READ && scsi_prot_sg_count(SCpnt))
- sd_dif_complete(SCpnt, good_bytes);
+ if (rq_data_dir(SCpnt->request) == READ && scsi_prot_sg_count(SCpnt) &&
+ good_bytes)
+ blk_integrity_dif_complete(SCpnt->request,
+ sdkp->protection_type,
+ scsi_prot_ref_tag(SCpnt),
+ good_bytes / scsi_prot_interval(SCpnt));
return good_bytes;
}
diff --git a/drivers/scsi/sd.h b/drivers/scsi/sd.h
index 392c7d078ae3..a7d4f50b67d4 100644
--- a/drivers/scsi/sd.h
+++ b/drivers/scsi/sd.h
@@ -254,21 +254,12 @@ static inline unsigned int sd_prot_flag_mask(unsigned int prot_op)
#ifdef CONFIG_BLK_DEV_INTEGRITY
extern void sd_dif_config_host(struct scsi_disk *);
-extern void sd_dif_prepare(struct scsi_cmnd *scmd);
-extern void sd_dif_complete(struct scsi_cmnd *, unsigned int);
#else /* CONFIG_BLK_DEV_INTEGRITY */
static inline void sd_dif_config_host(struct scsi_disk *disk)
{
}
-static inline int sd_dif_prepare(struct scsi_cmnd *scmd)
-{
- return 0;
-}
-static inline void sd_dif_complete(struct scsi_cmnd *cmd, unsigned int a)
-{
-}
#endif /* CONFIG_BLK_DEV_INTEGRITY */
diff --git a/drivers/scsi/sd_dif.c b/drivers/scsi/sd_dif.c
index 9035380c0dda..db72c82486e3 100644
--- a/drivers/scsi/sd_dif.c
+++ b/drivers/scsi/sd_dif.c
@@ -95,116 +95,3 @@ void sd_dif_config_host(struct scsi_disk *sdkp)
blk_integrity_register(disk, &bi);
}
-/*
- * The virtual start sector is the one that was originally submitted
- * by the block layer. 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.
- *
- * From a protocol perspective there's a slight difference between
- * Type 1 and 2. The latter uses 32-byte CDBs exclusively, and the
- * reference tag is seeded in the CDB. This gives us the potential to
- * avoid virt->phys remapping during write. However, at read time we
- * don't know whether the virt sector is the same as when we wrote it
- * (we could be reading from real disk as opposed to MD/DM device. So
- * we always remap Type 2 making it identical to Type 1.
- *
- * Type 3 does not have a reference tag so no remapping is required.
- */
-void sd_dif_prepare(struct scsi_cmnd *scmd)
-{
- const int tuple_sz = sizeof(struct t10_pi_tuple);
- struct bio *bio;
- struct scsi_disk *sdkp;
- struct t10_pi_tuple *pi;
- u32 phys, virt;
-
- sdkp = scsi_disk(scmd->request->rq_disk);
-
- if (sdkp->protection_type == T10_PI_TYPE3_PROTECTION)
- return;
-
- phys = scsi_prot_ref_tag(scmd);
-
- __rq_for_each_bio(bio, scmd->request) {
- struct bio_integrity_payload *bip = bio_integrity(bio);
- struct bio_vec iv;
- struct bvec_iter iter;
- unsigned int j;
-
- /* Already remapped? */
- if (bip->bip_flags & BIP_MAPPED_INTEGRITY)
- break;
-
- virt = bip_get_seed(bip) & 0xffffffff;
-
- bip_for_each_vec(iv, bip, iter) {
- pi = kmap_atomic(iv.bv_page) + iv.bv_offset;
-
- for (j = 0; j < iv.bv_len; j += tuple_sz, pi++) {
-
- if (be32_to_cpu(pi->ref_tag) == virt)
- pi->ref_tag = cpu_to_be32(phys);
-
- virt++;
- phys++;
- }
-
- kunmap_atomic(pi);
- }
-
- bip->bip_flags |= BIP_MAPPED_INTEGRITY;
- }
-}
-
-/*
- * Remap physical sector values in the reference tag to the virtual
- * values expected by the block layer.
- */
-void sd_dif_complete(struct scsi_cmnd *scmd, unsigned int good_bytes)
-{
- const int tuple_sz = sizeof(struct t10_pi_tuple);
- struct scsi_disk *sdkp;
- struct bio *bio;
- struct t10_pi_tuple *pi;
- unsigned int j, intervals;
- u32 phys, virt;
-
- sdkp = scsi_disk(scmd->request->rq_disk);
-
- if (sdkp->protection_type == T10_PI_TYPE3_PROTECTION || good_bytes == 0)
- return;
-
- intervals = good_bytes / scsi_prot_interval(scmd);
- phys = scsi_prot_ref_tag(scmd);
-
- __rq_for_each_bio(bio, scmd->request) {
- struct bio_integrity_payload *bip = bio_integrity(bio);
- struct bio_vec iv;
- struct bvec_iter iter;
-
- virt = bip_get_seed(bip) & 0xffffffff;
-
- bip_for_each_vec(iv, bip, iter) {
- pi = kmap_atomic(iv.bv_page) + iv.bv_offset;
-
- for (j = 0; j < iv.bv_len; j += tuple_sz, pi++) {
-
- if (intervals == 0) {
- kunmap_atomic(pi);
- return;
- }
-
- if (be32_to_cpu(pi->ref_tag) == phys)
- pi->ref_tag = cpu_to_be32(virt);
-
- virt++;
- phys++;
- intervals--;
- }
-
- kunmap_atomic(pi);
- }
- }
-}
-
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 79226ca8f80f..18f3ca17d4f4 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -1823,6 +1823,10 @@ extern bool blk_integrity_merge_rq(struct request_queue *, struct request *,
struct request *);
extern bool blk_integrity_merge_bio(struct request_queue *, struct request *,
struct bio *);
+extern void blk_integrity_dif_prepare(struct request *rq, u8 protection_type,
+ u32 ref_tag);
+extern void blk_integrity_dif_complete(struct request *rq, u8 protection_type,
+ u32 ref_tag, unsigned int intervals);
static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
{
@@ -1950,6 +1954,16 @@ static inline bool integrity_req_gap_front_merge(struct request *req,
return false;
}
+void blk_integrity_dif_prepare(struct request *rq, u8 protection_type,
+ u32 ref_tag)
+{
+}
+
+void blk_integrity_dif_complete(struct request *rq, u8 protection_type,
+ u32 ref_tag, unsigned int intervals)
+{
+}
+
#endif /* CONFIG_BLK_DEV_INTEGRITY */
struct block_device_operations {
--
2.16.3
