[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 <martin.petersen@oracle.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index 56b9501..8e08d51 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -373,6 +373,7 @@
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 @@
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 @@
}
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 @@
"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 @@
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 @@
}
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 @@
.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 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 @@
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 @@
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 @@
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 @@
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 " : "");