sd descriptor sense support

From: 	Douglas Gilbert <dougg@torque.net>

   - make all sd driver sense data handling able to use
     both fixed and descriptor format
   - permit 64 bit lbas associated with medium (or
     hardware) errors to be conveyed back to the block
     layer
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

drivers/scsi/sd.c

@@ -106,7 +106,7 @@ struct scsi_disk {
 };
 
 static DEFINE_IDR(sd_index_idr);
-static spinlock_t sd_index_lock = SPIN_LOCK_UNLOCKED;
+static DEFINE_SPINLOCK(sd_index_lock);
 
 /* This semaphore is used to mediate the 0->1 reference get in the
  * face of object destruction (i.e. we can't allow a get on an
@@ -763,15 +763,26 @@ static void sd_rw_intr(struct scsi_cmnd * SCpnt)
 	int this_count = SCpnt->bufflen;
 	int good_bytes = (result == 0 ? this_count : 0);
 	sector_t block_sectors = 1;
+	u64 first_err_block;
 	sector_t error_sector;
+	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);
+		if (sense_valid)
+			sense_deferred = scsi_sense_is_deferred(&sshdr);
+	}
+
 #ifdef CONFIG_SCSI_LOGGING
 	SCSI_LOG_HLCOMPLETE(1, printk("sd_rw_intr: %s: res=0x%x\n", 
 				SCpnt->request->rq_disk->disk_name, result));
-	if (0 != result) {
-		SCSI_LOG_HLCOMPLETE(1, printk("sd_rw_intr: sb[0,2,asc,ascq]"
-				"=%x,%x,%x,%x\n", SCpnt->sense_buffer[0],
-			SCpnt->sense_buffer[2], SCpnt->sense_buffer[12],
-			SCpnt->sense_buffer[13]));
+	if (sense_valid) {
+		SCSI_LOG_HLCOMPLETE(1, printk("sd_rw_intr: sb[respc,sk,asc,"
+				"ascq]=%x,%x,%x,%x\n", sshdr.response_code,
+				sshdr.sense_key, sshdr.asc, sshdr.ascq));
 	}
 #endif
 	/*
@@ -788,17 +799,19 @@ static void sd_rw_intr(struct scsi_cmnd * SCpnt)
 	if (blk_pc_request(SCpnt->request))
 		good_bytes = this_count;
 	else if (driver_byte(result) != 0 &&
-	    (SCpnt->sense_buffer[0] & 0x7f) == 0x70) {
-		switch (SCpnt->sense_buffer[2]) {
+		 sense_valid && !sense_deferred) {
+		switch (sshdr.sense_key) {
 		case MEDIUM_ERROR:
-			if (!(SCpnt->sense_buffer[0] & 0x80))
-				break;
 			if (!blk_fs_request(SCpnt->request))
 				break;
-			error_sector = (SCpnt->sense_buffer[3] << 24) |
-			(SCpnt->sense_buffer[4] << 16) |
-			(SCpnt->sense_buffer[5] << 8) |
-			SCpnt->sense_buffer[6];
+			info_valid = scsi_get_sense_info_fld(
+				SCpnt->sense_buffer, SCSI_SENSE_BUFFERSIZE,
+				&first_err_block);
+			/*
+			 * May want to warn and skip if following cast results
+			 * in actual truncation (if sector_t < 64 bits)
+			 */
+			error_sector = (sector_t)first_err_block;
 			if (SCpnt->request->bio != NULL)
 				block_sectors = bio_sectors(SCpnt->request->bio);
 			switch (SCpnt->device->sector_size) {
@@ -838,7 +851,7 @@ static void sd_rw_intr(struct scsi_cmnd * SCpnt)
 			 */
 			scsi_print_sense("sd", SCpnt);
 			SCpnt->result = 0;
-			SCpnt->sense_buffer[0] = 0x0;
+			memset(SCpnt->sense_buffer, 0, SCSI_SENSE_BUFFERSIZE);
 			good_bytes = this_count;
 			break;
 
@@ -867,16 +880,20 @@ static void sd_rw_intr(struct scsi_cmnd * SCpnt)
 
 static int media_not_present(struct scsi_disk *sdkp, struct scsi_request *srp)
 {
+	struct scsi_sense_hdr sshdr;
+
 	if (!srp->sr_result)
 		return 0;
 	if (!(driver_byte(srp->sr_result) & DRIVER_SENSE))
 		return 0;
-	if (srp->sr_sense_buffer[2] != NOT_READY &&
-	    srp->sr_sense_buffer[2] != UNIT_ATTENTION)
-	    	return 0;
-	if (srp->sr_sense_buffer[12] != 0x3A) /* medium not present */
-		return 0;
-
+	/* not invoked for commands that could return deferred errors */
+	if (scsi_request_normalize_sense(srp, &sshdr)) {
+		if (sshdr.sense_key != NOT_READY &&
+		    sshdr.sense_key != UNIT_ATTENTION)
+			return 0;
+		if (sshdr.asc != 0x3A) /* medium not present */
+			return 0;
+	}
 	set_media_not_present(sdkp);
 	return 1;
 }
@@ -891,6 +908,8 @@ sd_spinup_disk(struct scsi_disk *sdkp, char *diskname,
 	unsigned long spintime_value = 0;
 	int retries, spintime;
 	unsigned int the_result;
+	struct scsi_sense_hdr sshdr;
+	int sense_valid = 0;
 
 	spintime = 0;
 
@@ -904,19 +923,22 @@ sd_spinup_disk(struct scsi_disk *sdkp, char *diskname,
 			memset((void *) &cmd[1], 0, 9);
 
 			SRpnt->sr_cmd_len = 0;
-			SRpnt->sr_sense_buffer[0] = 0;
-			SRpnt->sr_sense_buffer[2] = 0;
+			memset(SRpnt->sr_sense_buffer, 0,
+			       SCSI_SENSE_BUFFERSIZE);
 			SRpnt->sr_data_direction = DMA_NONE;
 
 			scsi_wait_req (SRpnt, (void *) cmd, (void *) buffer,
 				       0/*512*/, SD_TIMEOUT, SD_MAX_RETRIES);
 
 			the_result = SRpnt->sr_result;
+			if (the_result)
+				sense_valid = scsi_request_normalize_sense(
+							SRpnt, &sshdr);
 			retries++;
 		} while (retries < 3 && 
 			 (!scsi_status_is_good(the_result) ||
 			  ((driver_byte(the_result) & DRIVER_SENSE) &&
-			   SRpnt->sr_sense_buffer[2] == UNIT_ATTENTION)));
+			  sense_valid && sshdr.sense_key == UNIT_ATTENTION)));
 
 		/*
 		 * If the drive has indicated to us that it doesn't have
@@ -930,7 +952,8 @@ sd_spinup_disk(struct scsi_disk *sdkp, char *diskname,
 			/* no sense, TUR either succeeded or failed
 			 * with a status error */
 			if(!spintime && !scsi_status_is_good(the_result))
-				printk(KERN_NOTICE "%s: Unit Not Ready, error = 0x%x\n", diskname, the_result);
+				printk(KERN_NOTICE "%s: Unit Not Ready, "
+				       "error = 0x%x\n", diskname, the_result);
 			break;
 		}
 					
@@ -945,15 +968,15 @@ sd_spinup_disk(struct scsi_disk *sdkp, char *diskname,
 		 * If manual intervention is required, or this is an
 		 * absent USB storage device, a spinup is meaningless.
 		 */
-		if (SRpnt->sr_sense_buffer[2] == NOT_READY &&
-		    SRpnt->sr_sense_buffer[12] == 4 /* not ready */ &&
-		    SRpnt->sr_sense_buffer[13] == 3) {
+		if (sense_valid &&
+		    sshdr.sense_key == NOT_READY &&
+		    sshdr.asc == 4 && sshdr.ascq == 3) {
 			break;		/* manual intervention required */
 
 		/*
 		 * Issue command to spin up drive when not ready
 		 */
-		} else if (SRpnt->sr_sense_buffer[2] == NOT_READY) {
+		} else if (sense_valid && sshdr.sense_key == NOT_READY) {
 			if (!spintime) {
 				printk(KERN_NOTICE "%s: Spinning up disk...",
 				       diskname);
@@ -962,8 +985,8 @@ sd_spinup_disk(struct scsi_disk *sdkp, char *diskname,
 				memset((void *) &cmd[2], 0, 8);
 				cmd[4] = 1;	/* Start spin cycle */
 				SRpnt->sr_cmd_len = 0;
-				SRpnt->sr_sense_buffer[0] = 0;
-				SRpnt->sr_sense_buffer[2] = 0;
+				memset(SRpnt->sr_sense_buffer, 0,
+					SCSI_SENSE_BUFFERSIZE);
 
 				SRpnt->sr_data_direction = DMA_NONE;
 				scsi_wait_req(SRpnt, (void *)cmd, 
@@ -979,7 +1002,8 @@ sd_spinup_disk(struct scsi_disk *sdkp, char *diskname,
 			/* we don't understand the sense code, so it's
 			 * probably pointless to loop */
 			if(!spintime) {
-				printk(KERN_NOTICE "%s: Unit Not Ready, sense:\n", diskname);
+				printk(KERN_NOTICE "%s: Unit Not Ready, "
+					"sense:\n", diskname);
 				scsi_print_req_sense("", SRpnt);
 			}
 			break;
@@ -1007,6 +1031,8 @@ sd_read_capacity(struct scsi_disk *sdkp, char *diskname,
 	int the_result, retries;
 	int sector_size = 0;
 	int longrc = 0;
+	struct scsi_sense_hdr sshdr;
+	int sense_valid = 0;
 
 repeat:
 	retries = 3;
@@ -1024,8 +1050,7 @@ sd_read_capacity(struct scsi_disk *sdkp, char *diskname,
 		}
 		
 		SRpnt->sr_cmd_len = 0;
-		SRpnt->sr_sense_buffer[0] = 0;
-		SRpnt->sr_sense_buffer[2] = 0;
+		memset(SRpnt->sr_sense_buffer, 0, SCSI_SENSE_BUFFERSIZE);
 		SRpnt->sr_data_direction = DMA_FROM_DEVICE;
 
 		scsi_wait_req(SRpnt, (void *) cmd, (void *) buffer,
@@ -1035,6 +1060,9 @@ sd_read_capacity(struct scsi_disk *sdkp, char *diskname,
 			return;
 
 		the_result = SRpnt->sr_result;
+		if (the_result)
+			sense_valid = scsi_request_normalize_sense(SRpnt,
+								   &sshdr);
 		retries--;
 
 	} while (the_result && retries);
@@ -1056,7 +1084,7 @@ sd_read_capacity(struct scsi_disk *sdkp, char *diskname,
 		/* Set dirty bit for removable devices if not ready -
 		 * sometimes drives will not report this properly. */
 		if (sdp->removable &&
-		    SRpnt->sr_sense_buffer[2] == NOT_READY)
+		    sense_valid && sshdr.sense_key == NOT_READY)
 			sdp->changed = 1;
 
 		/* Either no media are present but the drive didn't tell us,
@@ -1264,6 +1292,7 @@ sd_read_cache_type(struct scsi_disk *sdkp, char *diskname,
 	const int dbd = 0;	   /* DBD */
 	const int modepage = 0x08; /* current values, cache page */
 	struct scsi_mode_data data;
+	struct scsi_sense_hdr sshdr;
 
 	if (sdkp->device->skip_ms_page_8)
 		goto defaults;
@@ -1313,17 +1342,14 @@ sd_read_cache_type(struct scsi_disk *sdkp, char *diskname,
 	}
 
 bad_sense:
-	if ((SRpnt->sr_sense_buffer[0] & 0x70) == 0x70
-	     && (SRpnt->sr_sense_buffer[2] & 0x0f) == ILLEGAL_REQUEST
-	     /* ASC 0x24 ASCQ 0x00: Invalid field in CDB */
-	     && SRpnt->sr_sense_buffer[12] == 0x24
-	     && SRpnt->sr_sense_buffer[13] == 0x00) {
+	if (scsi_request_normalize_sense(SRpnt, &sshdr) &&
+	    sshdr.sense_key == ILLEGAL_REQUEST &&
+	    sshdr.asc == 0x24 && sshdr.ascq == 0x0)
 		printk(KERN_NOTICE "%s: cache data unavailable\n",
-		       diskname);
-	} else {
+		       diskname);	/* Invalid field in CDB */
+	else
 		printk(KERN_ERR "%s: asking for cache data failed\n",
 		       diskname);
-	}
 
 defaults:
 	printk(KERN_ERR "%s: assuming drive cache: write through\n",