sd: Honor block layer integrity handling flags
A set of flags introduced in the block layer enable better control over
how protection information is handled. These flags are useful for both
error injection and data recovery purposes. Checking can be enabled and
disabled for controller and disk, and the guard tag format is now a
per-I/O property.
Update sd_protect_op to communicate the relevant information to the
low-level device driver via a set of flags in scsi_cmnd.
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Acked-by: Christoph Hellwig <hch@lst.de>
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index 2c2041c..9f7099f 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -610,29 +610,44 @@
mutex_unlock(&sd_ref_mutex);
}
-static void sd_prot_op(struct scsi_cmnd *scmd, unsigned int dif)
-{
- unsigned int prot_op = SCSI_PROT_NORMAL;
- unsigned int dix = scsi_prot_sg_count(scmd);
- if (scmd->sc_data_direction == DMA_FROM_DEVICE) {
- if (dif && dix)
- prot_op = SCSI_PROT_READ_PASS;
- else if (dif && !dix)
- prot_op = SCSI_PROT_READ_STRIP;
- else if (!dif && dix)
- prot_op = SCSI_PROT_READ_INSERT;
- } else {
- if (dif && dix)
- prot_op = SCSI_PROT_WRITE_PASS;
- else if (dif && !dix)
- prot_op = SCSI_PROT_WRITE_INSERT;
- else if (!dif && dix)
- prot_op = SCSI_PROT_WRITE_STRIP;
+
+static unsigned char sd_setup_protect_cmnd(struct scsi_cmnd *scmd,
+ unsigned int dix, unsigned int dif)
+{
+ struct bio *bio = scmd->request->bio;
+ unsigned int prot_op = sd_prot_op(rq_data_dir(scmd->request), dix, dif);
+ unsigned int protect = 0;
+
+ if (dix) { /* DIX Type 0, 1, 2, 3 */
+ if (bio_integrity_flagged(bio, BIP_IP_CHECKSUM))
+ scmd->prot_flags |= SCSI_PROT_IP_CHECKSUM;
+
+ if (bio_integrity_flagged(bio, BIP_CTRL_NOCHECK) == false)
+ scmd->prot_flags |= SCSI_PROT_GUARD_CHECK;
+ }
+
+ if (dif != SD_DIF_TYPE3_PROTECTION) { /* DIX/DIF Type 0, 1, 2 */
+ scmd->prot_flags |= SCSI_PROT_REF_INCREMENT;
+
+ if (bio_integrity_flagged(bio, BIP_CTRL_NOCHECK) == false)
+ scmd->prot_flags |= SCSI_PROT_REF_CHECK;
+ }
+
+ if (dif) { /* DIX/DIF Type 1, 2, 3 */
+ scmd->prot_flags |= SCSI_PROT_TRANSFER_PI;
+
+ if (bio_integrity_flagged(bio, BIP_DISK_NOCHECK))
+ protect = 3 << 5; /* Disable target PI checking */
+ else
+ protect = 1 << 5; /* Enable target PI checking */
}
scsi_set_prot_op(scmd, prot_op);
scsi_set_prot_type(scmd, dif);
+ scmd->prot_flags &= sd_prot_flag_mask(prot_op);
+
+ return protect;
}
static void sd_config_discard(struct scsi_disk *sdkp, unsigned int mode)
@@ -893,7 +908,8 @@
sector_t block = blk_rq_pos(rq);
sector_t threshold;
unsigned int this_count = blk_rq_sectors(rq);
- int ret, host_dif;
+ unsigned int dif, dix;
+ int ret;
unsigned char protect;
ret = scsi_init_io(SCpnt, GFP_ATOMIC);
@@ -995,7 +1011,7 @@
SCpnt->cmnd[0] = WRITE_6;
if (blk_integrity_rq(rq))
- sd_dif_prepare(rq, block, sdp->sector_size);
+ sd_dif_prepare(SCpnt);
} else if (rq_data_dir(rq) == READ) {
SCpnt->cmnd[0] = READ_6;
@@ -1010,14 +1026,15 @@
"writing" : "reading", this_count,
blk_rq_sectors(rq)));
- /* Set RDPROTECT/WRPROTECT if disk is formatted with DIF */
- host_dif = scsi_host_dif_capable(sdp->host, sdkp->protection_type);
- if (host_dif)
- protect = 1 << 5;
+ dix = scsi_prot_sg_count(SCpnt);
+ dif = scsi_host_dif_capable(SCpnt->device->host, sdkp->protection_type);
+
+ if (dif || dix)
+ protect = sd_setup_protect_cmnd(SCpnt, dix, dif);
else
protect = 0;
- if (host_dif == SD_DIF_TYPE2_PROTECTION) {
+ if (protect && sdkp->protection_type == SD_DIF_TYPE2_PROTECTION) {
SCpnt->cmnd = mempool_alloc(sd_cdb_pool, GFP_ATOMIC);
if (unlikely(SCpnt->cmnd == NULL)) {
@@ -1102,10 +1119,6 @@
}
SCpnt->sdb.length = this_count * sdp->sector_size;
- /* If DIF or DIX is enabled, tell HBA how to handle request */
- if (host_dif || scsi_prot_sg_count(SCpnt))
- sd_prot_op(SCpnt, host_dif);
-
/*
* We shouldn't disconnect in the middle of a sector, so with a dumb
* host adapter, it's safe to assume that we can at least transfer
diff --git a/drivers/scsi/sd.h b/drivers/scsi/sd.h
index 4c3ab83..4673778 100644
--- a/drivers/scsi/sd.h
+++ b/drivers/scsi/sd.h
@@ -167,6 +167,68 @@
};
/*
+ * Look up the DIX operation based on whether the command is read or
+ * write and whether dix and dif are enabled.
+ */
+static inline unsigned int sd_prot_op(bool write, bool dix, bool dif)
+{
+ /* Lookup table: bit 2 (write), bit 1 (dix), bit 0 (dif) */
+ const unsigned int ops[] = { /* wrt dix dif */
+ SCSI_PROT_NORMAL, /* 0 0 0 */
+ SCSI_PROT_READ_STRIP, /* 0 0 1 */
+ SCSI_PROT_READ_INSERT, /* 0 1 0 */
+ SCSI_PROT_READ_PASS, /* 0 1 1 */
+ SCSI_PROT_NORMAL, /* 1 0 0 */
+ SCSI_PROT_WRITE_INSERT, /* 1 0 1 */
+ SCSI_PROT_WRITE_STRIP, /* 1 1 0 */
+ SCSI_PROT_WRITE_PASS, /* 1 1 1 */
+ };
+
+ return ops[write << 2 | dix << 1 | dif];
+}
+
+/*
+ * Returns a mask of the protection flags that are valid for a given DIX
+ * operation.
+ */
+static inline unsigned int sd_prot_flag_mask(unsigned int prot_op)
+{
+ const unsigned int flag_mask[] = {
+ [SCSI_PROT_NORMAL] = 0,
+
+ [SCSI_PROT_READ_STRIP] = SCSI_PROT_TRANSFER_PI |
+ SCSI_PROT_GUARD_CHECK |
+ SCSI_PROT_REF_CHECK |
+ SCSI_PROT_REF_INCREMENT,
+
+ [SCSI_PROT_READ_INSERT] = SCSI_PROT_REF_INCREMENT |
+ SCSI_PROT_IP_CHECKSUM,
+
+ [SCSI_PROT_READ_PASS] = SCSI_PROT_TRANSFER_PI |
+ SCSI_PROT_GUARD_CHECK |
+ SCSI_PROT_REF_CHECK |
+ SCSI_PROT_REF_INCREMENT |
+ SCSI_PROT_IP_CHECKSUM,
+
+ [SCSI_PROT_WRITE_INSERT] = SCSI_PROT_TRANSFER_PI |
+ SCSI_PROT_REF_INCREMENT,
+
+ [SCSI_PROT_WRITE_STRIP] = SCSI_PROT_GUARD_CHECK |
+ SCSI_PROT_REF_CHECK |
+ SCSI_PROT_REF_INCREMENT |
+ SCSI_PROT_IP_CHECKSUM,
+
+ [SCSI_PROT_WRITE_PASS] = SCSI_PROT_TRANSFER_PI |
+ SCSI_PROT_GUARD_CHECK |
+ SCSI_PROT_REF_CHECK |
+ SCSI_PROT_REF_INCREMENT |
+ SCSI_PROT_IP_CHECKSUM,
+ };
+
+ return flag_mask[prot_op];
+}
+
+/*
* Data Integrity Field tuple.
*/
struct sd_dif_tuple {
@@ -178,7 +240,7 @@
#ifdef CONFIG_BLK_DEV_INTEGRITY
extern void sd_dif_config_host(struct scsi_disk *);
-extern void sd_dif_prepare(struct request *rq, sector_t, unsigned int);
+extern void sd_dif_prepare(struct scsi_cmnd *scmd);
extern void sd_dif_complete(struct scsi_cmnd *, unsigned int);
#else /* CONFIG_BLK_DEV_INTEGRITY */
@@ -186,7 +248,7 @@
static inline void sd_dif_config_host(struct scsi_disk *disk)
{
}
-static inline int sd_dif_prepare(struct request *rq, sector_t s, unsigned int a)
+static inline int sd_dif_prepare(struct scsi_cmnd *scmd)
{
return 0;
}
diff --git a/drivers/scsi/sd_dif.c b/drivers/scsi/sd_dif.c
index b7eaead..14c7d42 100644
--- a/drivers/scsi/sd_dif.c
+++ b/drivers/scsi/sd_dif.c
@@ -106,8 +106,7 @@
*
* Type 3 does not have a reference tag so no remapping is required.
*/
-void sd_dif_prepare(struct request *rq, sector_t hw_sector,
- unsigned int sector_sz)
+void sd_dif_prepare(struct scsi_cmnd *scmd)
{
const int tuple_sz = sizeof(struct t10_pi_tuple);
struct bio *bio;
@@ -115,14 +114,14 @@
struct t10_pi_tuple *pi;
u32 phys, virt;
- sdkp = rq->bio->bi_bdev->bd_disk->private_data;
+ sdkp = scsi_disk(scmd->request->rq_disk);
if (sdkp->protection_type == SD_DIF_TYPE3_PROTECTION)
return;
- phys = hw_sector & 0xffffffff;
+ phys = scsi_prot_ref_tag(scmd);
- __rq_for_each_bio(bio, rq) {
+ __rq_for_each_bio(bio, scmd->request) {
struct bio_integrity_payload *bip = bio_integrity(bio);
struct bio_vec iv;
struct bvec_iter iter;
@@ -163,7 +162,7 @@
struct scsi_disk *sdkp;
struct bio *bio;
struct t10_pi_tuple *pi;
- unsigned int j, sectors, sector_sz;
+ unsigned int j, intervals;
u32 phys, virt;
sdkp = scsi_disk(scmd->request->rq_disk);
@@ -171,12 +170,8 @@
if (sdkp->protection_type == SD_DIF_TYPE3_PROTECTION || good_bytes == 0)
return;
- sector_sz = scmd->device->sector_size;
- sectors = good_bytes / sector_sz;
-
- phys = blk_rq_pos(scmd->request) & 0xffffffff;
- if (sector_sz == 4096)
- phys >>= 3;
+ 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);
@@ -190,7 +185,7 @@
for (j = 0; j < iv.bv_len; j += tuple_sz, pi++) {
- if (sectors == 0) {
+ if (intervals == 0) {
kunmap_atomic(pi);
return;
}
@@ -200,7 +195,7 @@
virt++;
phys++;
- sectors--;
+ intervals--;
}
kunmap_atomic(pi);
diff --git a/include/linux/bio.h b/include/linux/bio.h
index 14bff3f..ce6b759 100644
--- a/include/linux/bio.h
+++ b/include/linux/bio.h
@@ -292,6 +292,14 @@
*/
#define bio_get(bio) atomic_inc(&(bio)->bi_cnt)
+enum bip_flags {
+ BIP_BLOCK_INTEGRITY = 1 << 0, /* block layer owns integrity data */
+ BIP_MAPPED_INTEGRITY = 1 << 1, /* ref tag has been remapped */
+ BIP_CTRL_NOCHECK = 1 << 2, /* disable HBA integrity checking */
+ BIP_DISK_NOCHECK = 1 << 3, /* disable disk integrity checking */
+ BIP_IP_CHECKSUM = 1 << 4, /* IP checksum */
+};
+
#if defined(CONFIG_BLK_DEV_INTEGRITY)
static inline struct bio_integrity_payload *bio_integrity(struct bio *bio)
@@ -323,13 +331,15 @@
struct bio_vec bip_inline_vecs[0];/* embedded bvec array */
};
-enum bip_flags {
- BIP_BLOCK_INTEGRITY = 1 << 0, /* block layer owns integrity data */
- BIP_MAPPED_INTEGRITY = 1 << 1, /* ref tag has been remapped */
- BIP_CTRL_NOCHECK = 1 << 2, /* disable HBA integrity checking */
- BIP_DISK_NOCHECK = 1 << 3, /* disable disk integrity checking */
- BIP_IP_CHECKSUM = 1 << 4, /* IP checksum */
-};
+static inline bool bio_integrity_flagged(struct bio *bio, enum bip_flags flag)
+{
+ struct bio_integrity_payload *bip = bio_integrity(bio);
+
+ if (bip)
+ return bip->bip_flags & flag;
+
+ return false;
+}
static inline sector_t bip_get_seed(struct bio_integrity_payload *bip)
{
@@ -701,9 +711,9 @@
#else /* CONFIG_BLK_DEV_INTEGRITY */
-static inline int bio_integrity(struct bio *bio)
+static inline void *bio_integrity(struct bio *bio)
{
- return 0;
+ return NULL;
}
static inline bool bio_integrity_enabled(struct bio *bio)
@@ -754,6 +764,11 @@
return;
}
+static inline bool bio_integrity_flagged(struct bio *bio, enum bip_flags flag)
+{
+ return false;
+}
+
#endif /* CONFIG_BLK_DEV_INTEGRITY */
#endif /* CONFIG_BLOCK */
diff --git a/include/scsi/scsi_cmnd.h b/include/scsi/scsi_cmnd.h
index 73f3490..522a5f27 100644
--- a/include/scsi/scsi_cmnd.h
+++ b/include/scsi/scsi_cmnd.h
@@ -10,9 +10,10 @@
#include <scsi/scsi_device.h>
struct Scsi_Host;
-struct scsi_device;
struct scsi_driver;
+#include <scsi/scsi_device.h>
+
/*
* MAX_COMMAND_SIZE is:
* The longest fixed-length SCSI CDB as per the SCSI standard.
@@ -81,6 +82,7 @@
unsigned char prot_op;
unsigned char prot_type;
+ unsigned char prot_flags;
unsigned short cmd_len;
enum dma_data_direction sc_data_direction;
@@ -252,6 +254,14 @@
return scmd->prot_op;
}
+enum scsi_prot_flags {
+ SCSI_PROT_TRANSFER_PI = 1 << 0,
+ SCSI_PROT_GUARD_CHECK = 1 << 1,
+ SCSI_PROT_REF_CHECK = 1 << 2,
+ SCSI_PROT_REF_INCREMENT = 1 << 3,
+ SCSI_PROT_IP_CHECKSUM = 1 << 4,
+};
+
/*
* The controller usually does not know anything about the target it
* is communicating with. However, when DIX is enabled the controller
@@ -280,6 +290,17 @@
return blk_rq_pos(scmd->request);
}
+static inline unsigned int scsi_prot_interval(struct scsi_cmnd *scmd)
+{
+ return scmd->device->sector_size;
+}
+
+static inline u32 scsi_prot_ref_tag(struct scsi_cmnd *scmd)
+{
+ return blk_rq_pos(scmd->request) >>
+ (ilog2(scsi_prot_interval(scmd)) - 9) & 0xffffffff;
+}
+
static inline unsigned scsi_prot_sg_count(struct scsi_cmnd *cmd)
{
return cmd->prot_sdb ? cmd->prot_sdb->table.nents : 0;
@@ -316,17 +337,12 @@
static inline unsigned scsi_transfer_length(struct scsi_cmnd *scmd)
{
unsigned int xfer_len = scsi_out(scmd)->length;
- unsigned int prot_op = scsi_get_prot_op(scmd);
- unsigned int sector_size = scmd->device->sector_size;
+ unsigned int prot_interval = scsi_prot_interval(scmd);
- switch (prot_op) {
- case SCSI_PROT_NORMAL:
- case SCSI_PROT_WRITE_STRIP:
- case SCSI_PROT_READ_INSERT:
- return xfer_len;
- }
+ if (scmd->prot_flags & SCSI_PROT_TRANSFER_PI)
+ xfer_len += (xfer_len >> ilog2(prot_interval)) * 8;
- return xfer_len + (xfer_len >> ilog2(sector_size)) * 8;
+ return xfer_len;
}
#endif /* _SCSI_SCSI_CMND_H */
