Commit af55ff67 authored by Martin K. Petersen's avatar Martin K. Petersen Committed by James Bottomley

[SCSI] sd: Support for SCSI disk (SBC) Data Integrity Field

Support for controllers and disks that implement DIF protection
information:

 - During command preparation the RDPROTECT/WRPROTECT must be set
   correctly if the target has DIF enabled.

 - READ(6) and WRITE(6) are not supported when DIF is on.

 - The controller must be told how to handle the I/O via the
   protection operation field in scsi_cmnd.

 - Refactor the I/O completion code that extracts failed LBA from the
   returned sense data and handle DIF failures correctly.

 - sd_dif.c implements the functions required to prepare and complete
   requests with protection information attached.
Signed-off-by: Martin K. Petersen's avatarMartin K. Petersen <[email protected]>
Signed-off-by: default avatarJames Bottomley <[email protected]>
parent e0597d70
......@@ -63,6 +63,7 @@ comment "SCSI support type (disk, tape, CD-ROM)"
config BLK_DEV_SD
tristate "SCSI disk support"
depends on SCSI
select CRC_T10DIF
---help---
If you want to use SCSI hard disks, Fibre Channel disks,
Serial ATA (SATA) or Parallel ATA (PATA) hard disks,
......
......@@ -151,6 +151,8 @@ scsi_mod-$(CONFIG_SCSI_PROC_FS) += scsi_proc.o
scsi_tgt-y += scsi_tgt_lib.o scsi_tgt_if.o
sd_mod-objs := sd.o
sd_mod-$(CONFIG_BLK_DEV_INTEGRITY) += sd_dif.o
sr_mod-objs := sr.o sr_ioctl.o sr_vendor.o
ncr53c8xx-flags-$(CONFIG_SCSI_ZALON) \
:= -DCONFIG_NCR53C8XX_PREFETCH -DSCSI_NCR_BIG_ENDIAN \
......
......@@ -373,6 +373,7 @@ static int sd_prep_fn(struct request_queue *q, struct request *rq)
struct scsi_cmnd *SCpnt;
struct scsi_device *sdp = q->queuedata;
struct gendisk *disk = rq->rq_disk;
struct scsi_disk *sdkp;
sector_t block = rq->sector;
unsigned int this_count = rq->nr_sectors;
unsigned int timeout = sdp->timeout;
......@@ -389,6 +390,7 @@ static int sd_prep_fn(struct request_queue *q, struct request *rq)
if (ret != BLKPREP_OK)
goto out;
SCpnt = rq->special;
sdkp = scsi_disk(disk);
/* from here on until we're complete, any goto out
* is used for a killable error condition */
......@@ -478,6 +480,11 @@ static int sd_prep_fn(struct request_queue *q, struct request *rq)
}
SCpnt->cmnd[0] = WRITE_6;
SCpnt->sc_data_direction = DMA_TO_DEVICE;
if (blk_integrity_rq(rq) &&
sd_dif_prepare(rq, block, sdp->sector_size) == -EIO)
goto out;
} else if (rq_data_dir(rq) == READ) {
SCpnt->cmnd[0] = READ_6;
SCpnt->sc_data_direction = DMA_FROM_DEVICE;
......@@ -492,8 +499,12 @@ static int sd_prep_fn(struct request_queue *q, struct request *rq)
"writing" : "reading", this_count,
rq->nr_sectors));
SCpnt->cmnd[1] = 0;
/* Set RDPROTECT/WRPROTECT if disk is formatted with DIF */
if (scsi_host_dif_capable(sdp->host, sdkp->protection_type))
SCpnt->cmnd[1] = 1 << 5;
else
SCpnt->cmnd[1] = 0;
if (block > 0xffffffff) {
SCpnt->cmnd[0] += READ_16 - READ_6;
SCpnt->cmnd[1] |= blk_fua_rq(rq) ? 0x8 : 0;
......@@ -511,6 +522,7 @@ static int sd_prep_fn(struct request_queue *q, struct request *rq)
SCpnt->cmnd[13] = (unsigned char) this_count & 0xff;
SCpnt->cmnd[14] = SCpnt->cmnd[15] = 0;
} else if ((this_count > 0xff) || (block > 0x1fffff) ||
scsi_device_protection(SCpnt->device) ||
SCpnt->device->use_10_for_rw) {
if (this_count > 0xffff)
this_count = 0xffff;
......@@ -545,6 +557,10 @@ static int sd_prep_fn(struct request_queue *q, struct request *rq)
}
SCpnt->sdb.length = this_count * sdp->sector_size;
/* If DIF or DIX is enabled, tell HBA how to handle request */
if (sdkp->protection_type || scsi_prot_sg_count(SCpnt))
sd_dif_op(SCpnt, sdkp->protection_type, scsi_prot_sg_count(SCpnt));
/*
* 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
......@@ -939,6 +955,48 @@ static struct block_device_operations sd_fops = {
.revalidate_disk = sd_revalidate_disk,
};
static unsigned int sd_completed_bytes(struct scsi_cmnd *scmd)
{
u64 start_lba = scmd->request->sector;
u64 end_lba = scmd->request->sector + (scsi_bufflen(scmd) / 512);
u64 bad_lba;
int info_valid;
if (!blk_fs_request(scmd->request))
return 0;
info_valid = scsi_get_sense_info_fld(scmd->sense_buffer,
SCSI_SENSE_BUFFERSIZE,
&bad_lba);
if (!info_valid)
return 0;
if (scsi_bufflen(scmd) <= scmd->device->sector_size)
return 0;
if (scmd->device->sector_size < 512) {
/* only legitimate sector_size here is 256 */
start_lba <<= 1;
end_lba <<= 1;
} else {
/* be careful ... don't want any overflows */
u64 factor = scmd->device->sector_size / 512;
do_div(start_lba, factor);
do_div(end_lba, factor);
}
/* The bad lba was reported incorrectly, we have no idea where
* the error is.
*/
if (bad_lba < start_lba || bad_lba >= end_lba)
return 0;
/* This computation should always be done in terms of
* the resolution of the device's medium.
*/
return (bad_lba - start_lba) * scmd->device->sector_size;
}
/**
* sd_done - bottom half handler: called when the lower level
* driver has completed (successfully or otherwise) a scsi command.
......@@ -949,15 +1007,10 @@ static struct block_device_operations sd_fops = {
static int sd_done(struct scsi_cmnd *SCpnt)
{
int result = SCpnt->result;
unsigned int xfer_size = scsi_bufflen(SCpnt);
unsigned int good_bytes = result ? 0 : xfer_size;
u64 start_lba = SCpnt->request->sector;
u64 end_lba = SCpnt->request->sector + (xfer_size / 512);
u64 bad_lba;
unsigned int good_bytes = result ? 0 : scsi_bufflen(SCpnt);
struct scsi_sense_hdr sshdr;
int sense_valid = 0;
int sense_deferred = 0;
int info_valid;
if (result) {
sense_valid = scsi_command_normalize_sense(SCpnt, &sshdr);
......@@ -982,36 +1035,7 @@ static int sd_done(struct scsi_cmnd *SCpnt)
switch (sshdr.sense_key) {
case HARDWARE_ERROR:
case MEDIUM_ERROR:
if (!blk_fs_request(SCpnt->request))
goto out;
info_valid = scsi_get_sense_info_fld(SCpnt->sense_buffer,
SCSI_SENSE_BUFFERSIZE,
&bad_lba);
if (!info_valid)
goto out;
if (xfer_size <= SCpnt->device->sector_size)
goto out;
if (SCpnt->device->sector_size < 512) {
/* only legitimate sector_size here is 256 */
start_lba <<= 1;
end_lba <<= 1;
} else {
/* be careful ... don't want any overflows */
u64 factor = SCpnt->device->sector_size / 512;
do_div(start_lba, factor);
do_div(end_lba, factor);
}
if (bad_lba < start_lba || bad_lba >= end_lba)
/* the bad lba was reported incorrectly, we have
* no idea where the error is
*/
goto out;
/* This computation should always be done in terms of
* the resolution of the device's medium.
*/
good_bytes = (bad_lba - start_lba)*SCpnt->device->sector_size;
good_bytes = sd_completed_bytes(SCpnt);
break;
case RECOVERED_ERROR:
case NO_SENSE:
......@@ -1021,10 +1045,23 @@ static int sd_done(struct scsi_cmnd *SCpnt)
scsi_print_sense("sd", SCpnt);
SCpnt->result = 0;
memset(SCpnt->sense_buffer, 0, SCSI_SENSE_BUFFERSIZE);
good_bytes = xfer_size;
good_bytes = scsi_bufflen(SCpnt);
break;
case ABORTED_COMMAND:
if (sshdr.asc == 0x10) { /* DIF: Disk detected corruption */
scsi_print_result(SCpnt);
scsi_print_sense("sd", SCpnt);
good_bytes = sd_completed_bytes(SCpnt);
}
break;
case ILLEGAL_REQUEST:
if (SCpnt->device->use_10_for_rw &&
if (sshdr.asc == 0x10) { /* DIX: HBA detected corruption */
scsi_print_result(SCpnt);
scsi_print_sense("sd", SCpnt);
good_bytes = sd_completed_bytes(SCpnt);
}
if (!scsi_device_protection(SCpnt->device) &&
SCpnt->device->use_10_for_rw &&
(SCpnt->cmnd[0] == READ_10 ||
SCpnt->cmnd[0] == WRITE_10))
SCpnt->device->use_10_for_rw = 0;
......@@ -1037,6 +1074,9 @@ static int sd_done(struct scsi_cmnd *SCpnt)
break;
}
out:
if (rq_data_dir(SCpnt->request) == READ && scsi_prot_sg_count(SCpnt))
sd_dif_complete(SCpnt, good_bytes);
return good_bytes;
}
......@@ -1826,6 +1866,7 @@ static int sd_probe(struct device *dev)
dev_set_drvdata(dev, sdkp);
add_disk(gd);
sd_dif_config_host(sdkp);
sd_printk(KERN_NOTICE, sdkp, "Attached SCSI %sdisk\n",
sdp->removable ? "removable " : "");
......
......@@ -82,4 +82,29 @@ enum sd_dif_target_protection_types {
SD_DIF_TYPE3_PROTECTION = 0x3,
};
/*
* Data Integrity Field tuple.
*/
struct sd_dif_tuple {
__be16 guard_tag; /* Checksum */
__be16 app_tag; /* Opaque storage */
__be32 ref_tag; /* Target LBA or indirect LBA */
};
#if defined(CONFIG_BLK_DEV_INTEGRITY)
extern void sd_dif_op(struct scsi_cmnd *, unsigned int, unsigned int);
extern void sd_dif_config_host(struct scsi_disk *);
extern int sd_dif_prepare(struct request *rq, sector_t, unsigned int);
extern void sd_dif_complete(struct scsi_cmnd *, unsigned int);
#else /* CONFIG_BLK_DEV_INTEGRITY */
#define sd_dif_op(a, b, c) do { } while (0)
#define sd_dif_config_host(a) do { } while (0)
#define sd_dif_prepare(a, b, c) (0)
#define sd_dif_complete(a, b) (0)
#endif /* CONFIG_BLK_DEV_INTEGRITY */
#endif /* _SCSI_DISK_H */
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