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block: move dif_prepare/dif_complete functions to block layer

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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>
This commit is contained in:
Max Gurtovoy 2018-07-30 00:15:32 +03:00 committed by Jens Axboe
parent ddd0bc7569
commit 10c41ddd61
5 changed files with 118 additions and 125 deletions
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110
block/t10-pi.c
View File

@ -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);

8
drivers/scsi/sd.c
View File

@ -1119,7 +1119,7 @@ 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);
t10_pi_prepare(SCpnt->request, sdkp->protection_type);
} else if (rq_data_dir(rq) == READ) {
SCpnt->cmnd[0] = READ_6;
@ -2047,8 +2047,10 @@ 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)
t10_pi_complete(SCpnt->request, sdkp->protection_type,
good_bytes / scsi_prot_interval(SCpnt));
return good_bytes;
}

9
drivers/scsi/sd.h
View File

@ -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 */

113
drivers/scsi/sd_dif.c
View File

@ -95,116 +95,3 @@ out:
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 = t10_pi_ref_tag(scmd->request);
__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 = t10_pi_ref_tag(scmd->request);
__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);
}
}
}

3
include/linux/t10-pi.h
View File

@ -51,5 +51,8 @@ extern const struct blk_integrity_profile t10_pi_type1_crc;
extern const struct blk_integrity_profile t10_pi_type1_ip;
extern const struct blk_integrity_profile t10_pi_type3_crc;
extern const struct blk_integrity_profile t10_pi_type3_ip;
extern void t10_pi_prepare(struct request *rq, u8 protection_type);
extern void t10_pi_complete(struct request *rq, u8 protection_type,
unsigned int intervals);
#endif