SCSI Data Integrity Support

@@ -249,6 +249,8 @@ shost_rd_attr(can_queue, "%hd\n");
 shost_rd_attr(can_queue, "%hd\n");
 shost_rd_attr(sg_tablesize, "%hu\n");
 shost_rd_attr(unchecked_isa_dma, "%d\n");
+shost_rd_attr(prot_capabilities, "%u\n");
+shost_rd_attr(prot_guard_type, "%hd\n");
 shost_rd_attr2(proc_name, hostt->proc_name, "%s\n");
 
 static struct attribute *scsi_sysfs_shost_attrs[] = {

@@ -263,6 +265,8 @@ static struct attribute *scsi_sysfs_shos
 	&dev_attr_hstate.attr,
 	&dev_attr_supported_mode.attr,
 	&dev_attr_active_mode.attr,
+	&dev_attr_prot_capabilities.attr,
+	&dev_attr_prot_guard_type.attr,
 	NULL
 };
 

96 lines not on this page · raw message

@@ -333,6 +333,9 @@ static int scsi_check_sense(struct scsi_
 		return /* soft_error */ SUCCESS;
 
 	case ABORTED_COMMAND:
+		if (sshdr.asc == 0x10) /* DIF */
+			return SUCCESS;
+
 		return NEEDS_RETRY;
 	case NOT_READY:
 	case UNIT_ATTENTION:

@@ -941,11 +941,14 @@ void scsi_io_completion(struct scsi_cmnd
 				 * 6-byte command.
 				 */
 				scsi_requeue_command(q, cmd);
-				return;
-			} else {
+			} else if (sshdr.asc == 0x10) /* DIX */
+				scsi_end_request(cmd, -EIO, good_bytes, 0);
+			else
 				scsi_end_request(cmd, -EIO, this_count, 1);
-				return;
-			}
+			return;
+		case ABORTED_COMMAND:
+			if (sshdr.asc == 0x10) /* DIF */
+				scsi_end_request(cmd, -EIO, good_bytes, 0);
 			break;
 		case NOT_READY:
 			/* If the device is in the process of becoming

@@ -199,24 +199,60 @@ scsi_pool_free_command(struct scsi_host_
 {
 	kmem_cache_free(pool->sense_slab, cmd->sense_buffer);
 	kmem_cache_free(pool->cmd_slab, cmd);
+
+	if (cmd->prot_sdb)
+		kmem_cache_free(scsi_sdb_cache, cmd->prot_sdb);
+}
+
+/**
+ * scsi_host_alloc_command - internal function to allocate command
+ * @shost:	SCSI host whose pool to allocate from
+ * @gfp_mask:	mask for the allocation
+ *
+ * Returns a fully allocated command with sense buffer and protection
+ * data buffer (where applicable) or NULL on failure
+ */
+static struct scsi_cmnd *
+scsi_host_alloc_command(struct Scsi_Host *shost, gfp_t gfp_mask)
+{
+	struct scsi_cmnd *cmd;
+
+	cmd = scsi_pool_alloc_command(shost->cmd_pool, gfp_mask);
+	if (!cmd)
+		return NULL;
+
+	if (scsi_host_get_prot(shost) >= SHOST_DIX_TYPE0_PROTECTION) {
+		cmd->prot_sdb = kmem_cache_zalloc(scsi_sdb_cache, gfp_mask);
+
+		if (!cmd->prot_sdb) {
+			scsi_pool_free_command(shost->cmd_pool, cmd);
+			return NULL;
+		}
+	}
+
+	return cmd;
 }
 
 /**
  * __scsi_get_command - Allocate a struct scsi_cmnd
  * @shost: host to transmit command
  * @gfp_mask: allocation mask
+ * @protection: allocate protection sdb
  *
  * Description: allocate a struct scsi_cmd from host's slab, recycling from the
  *              host's free_list if necessary.
  */
-struct scsi_cmnd *__scsi_get_command(struct Scsi_Host *shost, gfp_t gfp_mask)
+struct scsi_cmnd *__scsi_get_command(struct Scsi_Host *shost, gfp_t gfp_mask, int protection)
 {
 	struct scsi_cmnd *cmd;
 	unsigned char *buf;
 
 	cmd = scsi_pool_alloc_command(shost->cmd_pool, gfp_mask);
 
-	if (unlikely(!cmd)) {
+	if (protection)
+		cmd->prot_sdb = kmem_cache_zalloc(scsi_sdb_cache, gfp_mask);
+
+	if (unlikely(!cmd) || unlikely(protection && cmd->prot_sdb == NULL)) {
 		unsigned long flags;
 
 		spin_lock_irqsave(&shost->free_list_lock, flags);

@@ -242,10 +278,11 @@ EXPORT_SYMBOL_GPL(__scsi_get_command);
  * scsi_get_command - Allocate and setup a scsi command block
  * @dev: parent scsi device
  * @gfp_mask: allocator flags
+ * @protection: allocate protection sdb
  *
  * Returns:	The allocated scsi command structure.
  */
-struct scsi_cmnd *scsi_get_command(struct scsi_device *dev, gfp_t gfp_mask)
+struct scsi_cmnd *scsi_get_command(struct scsi_device *dev, gfp_t gfp_mask, int protection)
 {
 	struct scsi_cmnd *cmd;
 

@@ -253,7 +290,7 @@ struct scsi_cmnd *scsi_get_command(struc
 	if (!get_device(&dev->sdev_gendev))
 		return NULL;
 
-	cmd = __scsi_get_command(dev->host, gfp_mask);
+	cmd = __scsi_get_command(dev->host, gfp_mask, protection);
 
 	if (likely(cmd != NULL)) {
 		unsigned long flags;

@@ -457,7 +494,7 @@ int scsi_setup_command_freelist(struct S
 	/*
 	 * Get one backup command for this host.
 	 */
-	cmd = scsi_pool_alloc_command(shost->cmd_pool, gfp_mask);
+	cmd = scsi_host_alloc_command(shost, gfp_mask);
 	if (!cmd) {
 		scsi_put_host_cmd_pool(gfp_mask);
 		shost->cmd_pool = NULL;

@@ -1769,7 +1769,7 @@ int
 int
 scsi_reset_provider(struct scsi_device *dev, int flag)
 {
-	struct scsi_cmnd *scmd = scsi_get_command(dev, GFP_KERNEL);
+	struct scsi_cmnd *scmd = scsi_get_command(dev, GFP_KERNEL, 0);
 	struct Scsi_Host *shost = dev->host;
 	struct request req;
 	unsigned long flags;

@@ -65,7 +65,7 @@ static struct scsi_host_sg_pool scsi_sg_
 };
 #undef SP
 
-static struct kmem_cache *scsi_sdb_cache;
+struct kmem_cache *scsi_sdb_cache;
 
 static void scsi_run_queue(struct request_queue *q);
 

@@ -778,6 +778,9 @@ void scsi_release_buffers(struct scsi_cm
 		kmem_cache_free(scsi_sdb_cache, bidi_sdb);
 		cmd->request->next_rq->special = NULL;
 	}
+
+	if (scsi_prot_sg_count(cmd))
+		scsi_free_sgtable(cmd->prot_sdb);
 }
 EXPORT_SYMBOL(scsi_release_buffers);
 

@@ -1063,6 +1066,26 @@ int scsi_init_io(struct scsi_cmnd *cmd, 
 			goto err_exit;
 	}
 
+	if (blk_integrity_rq(cmd->request)) {
+		struct scsi_data_buffer *prot_sdb = cmd->prot_sdb;
+		int ivecs, count;
+
+		BUG_ON(prot_sdb == NULL);
+		ivecs = blk_rq_count_integrity_sg(cmd->request);
+
+		if (scsi_alloc_sgtable(prot_sdb, ivecs, gfp_mask)) {
+			error = BLKPREP_DEFER;
+			goto err_exit;
+		}
+
+		count = blk_rq_map_integrity_sg(cmd->request,
+						prot_sdb->table.sgl);
+		BUG_ON(unlikely(count > ivecs));
+
+		cmd->prot_sdb = prot_sdb;
+		cmd->prot_sdb->table.nents = count;
+	}
+
 	return BLKPREP_OK ;
 
 err_exit:

@@ -1082,7 +1105,7 @@ static struct scsi_cmnd *scsi_get_cmd_fr
 	struct scsi_cmnd *cmd;
 
 	if (!req->special) {
-		cmd = scsi_get_command(sdev, GFP_ATOMIC);
+		cmd = scsi_get_command(sdev, GFP_ATOMIC, blk_integrity_rq(req));
 		if (unlikely(!cmd))
 			return NULL;
 		req->special = cmd;

@@ -77,6 +77,7 @@ struct request_queue;
 struct request_queue;
 struct request;
 extern int scsi_prep_fn(struct request_queue *, struct request *);
+extern struct kmem_cache *scsi_sdb_cache;
 
 /* scsi_proc.c */
 #ifdef CONFIG_SCSI_PROC_FS

@@ -99,7 +99,7 @@ struct scsi_cmnd *scsi_host_get_command(
 	if (!rq)
 		goto free_tcmd;
 
-	cmd = __scsi_get_command(shost, gfp_mask);
+	cmd = __scsi_get_command(shost, gfp_mask, 0);
 	if (!cmd)
 		goto release_rq;
 

@@ -90,6 +90,8 @@ struct scsi_cmnd {
 
 	/* These elements define the operation we ultimately want to perform */
 	struct scsi_data_buffer sdb;
+	struct scsi_data_buffer *prot_sdb;
+
 	unsigned underflow;	/* Return error if less than
 				   this amount is transferred */
 

@@ -131,8 +133,8 @@ struct scsi_cmnd {
 	unsigned char tag;	/* SCSI-II queued command tag */
 };
 
-extern struct scsi_cmnd *scsi_get_command(struct scsi_device *, gfp_t);
-extern struct scsi_cmnd *__scsi_get_command(struct Scsi_Host *, gfp_t);
+extern struct scsi_cmnd *scsi_get_command(struct scsi_device *, gfp_t, int);
+extern struct scsi_cmnd *__scsi_get_command(struct Scsi_Host *, gfp_t, int);
 extern void scsi_put_command(struct scsi_cmnd *);
 extern void __scsi_put_command(struct Scsi_Host *, struct scsi_cmnd *,
 			       struct device *);

@@ -237,4 +239,22 @@ enum scsi_prot_operations {
 	SCSI_PROT_WRITE_CONVERT,
 };
 
+static inline unsigned scsi_prot_sg_count(struct scsi_cmnd *cmd)
+{
+	return cmd->prot_sdb ? cmd->prot_sdb->table.nents : 0;
+}
+
+static inline struct scatterlist *scsi_prot_sglist(struct scsi_cmnd *cmd)
+{
+	return cmd->prot_sdb ? cmd->prot_sdb->table.sgl : NULL;
+}
+
+static inline struct scsi_data_buffer *scsi_prot(struct scsi_cmnd *cmd)
+{
+	return cmd->prot_sdb;
+}
+
+#define scsi_for_each_prot_sg(cmd, sg, nseg, __i)		\
+	for_each_sg(scsi_prot_sglist(cmd), sg, nseg, __i)
+
 #endif /* _SCSI_SCSI_CMND_H */

@@ -393,6 +393,11 @@ static inline int scsi_device_enclosure(
 	return sdev->inquiry[6] & (1<<6);
 }
 
+static inline int scsi_device_protection(struct scsi_device *sdev)
+{
+	return sdev->inquiry[5] & (1<<0);
+}
+
 #define MODULE_ALIAS_SCSI_DEVICE(type) \
 	MODULE_ALIAS("scsi:t-" __stringify(type) "*")
 #define SCSI_DEVICE_MODALIAS_FMT "scsi:t-0x%02x"

@@ -653,7 +653,9 @@ void scsi_eh_prep_cmnd(struct scsi_cmnd 
 	ses->sdb = scmd->sdb;
 	ses->next_rq = scmd->request->next_rq;
 	ses->result = scmd->result;
+	ses->prot_op = scmd->prot_op;
 
+	scmd->prot_op = SCSI_PROT_NORMAL;
 	scmd->cmnd = ses->eh_cmnd;
 	memset(scmd->cmnd, 0, BLK_MAX_CDB);
 	memset(&scmd->sdb, 0, sizeof(scmd->sdb));

@@ -711,6 +713,7 @@ void scsi_eh_restore_cmnd(struct scsi_cm
 	scmd->sdb = ses->sdb;
 	scmd->request->next_rq = ses->next_rq;
 	scmd->result = ses->result;
+	scmd->prot_op = ses->prot_op;
 }
 EXPORT_SYMBOL(scsi_eh_restore_cmnd);
 

@@ -77,6 +77,8 @@ struct scsi_cmnd {
 	int retries;
 	int allowed;
 	int timeout_per_command;
+
+	unsigned char prot_op;
 
 	unsigned short cmd_len;
 	enum dma_data_direction sc_data_direction;

@@ -209,4 +211,30 @@ static inline int scsi_sg_copy_to_buffer
 				 buf, buflen);
 }
 
+/*
+ * The operations below are hints that tell the controller driver how
+ * to handle I/Os with DIF or similar types of protection information.
+ */
+
+enum scsi_prot_operations {
+	/* Normal I/O */
+	SCSI_PROT_NORMAL = 0,
+
+	/* OS-HBA: Protected, HBA-Target: Unprotected */
+	SCSI_PROT_READ_INSERT,
+	SCSI_PROT_WRITE_STRIP,
+
+	/* OS-HBA: Unprotected, HBA-Target: Protected */
+	SCSI_PROT_READ_STRIP,
+	SCSI_PROT_WRITE_INSERT,
+
+	/* OS-HBA: Protected, HBA-Target: Protected */
+	SCSI_PROT_READ_PASS,
+	SCSI_PROT_WRITE_PASS,
+
+	/* OS-HBA: Protected, HBA-Target: Protected, checksum conversion */
+	SCSI_PROT_READ_CONVERT,
+	SCSI_PROT_WRITE_CONVERT,
+};
+
 #endif /* _SCSI_SCSI_CMND_H */

@@ -75,6 +75,7 @@ struct scsi_eh_save {
 	int result;
 	enum dma_data_direction data_direction;
 	unsigned char cmd_len;
+	unsigned char prot_op;
 	unsigned char *cmnd;
 	struct scsi_data_buffer sdb;
 	struct request *next_rq;

198 lines not on this page · raw message

@@ -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 */

533 lines not on this page · raw message

@@ -234,6 +234,24 @@ sd_show_allow_restart(struct device *dev
 	return snprintf(buf, 40, "%d\n", sdkp->device->allow_restart);
 }
 
+static ssize_t
+sd_show_protection_type(struct device *dev, struct device_attribute *attr,
+			char *buf)
+{
+	struct scsi_disk *sdkp = to_scsi_disk(dev);
+
+	return snprintf(buf, 20, "%u\n", sdkp->protection_type);
+}
+
+static ssize_t
+sd_show_app_tag_own(struct device *dev, struct device_attribute *attr,
+		    char *buf)
+{
+	struct scsi_disk *sdkp = to_scsi_disk(dev);
+
+	return snprintf(buf, 20, "%u\n", sdkp->ATO);
+}
+
 static struct device_attribute sd_disk_attrs[] = {
 	__ATTR(cache_type, S_IRUGO|S_IWUSR, sd_show_cache_type,
 	       sd_store_cache_type),

@@ -242,6 +260,8 @@ static struct device_attribute sd_disk_a
 	       sd_store_allow_restart),
 	__ATTR(manage_start_stop, S_IRUGO|S_IWUSR, sd_show_manage_start_stop,
 	       sd_store_manage_start_stop),
+	__ATTR(protection_type, S_IRUGO, sd_show_protection_type, NULL),
+	__ATTR(app_tag_own, S_IRUGO, sd_show_app_tag_own, NULL),
 	__ATTR_NULL,
 };
 

@@ -1163,6 +1183,49 @@ sd_spinup_disk(struct scsi_disk *sdkp)
 	}
 }
 
+
+/*
+ * Determine whether disk supports Data Integrity Field.
+ */
+void sd_read_protection_type(struct scsi_disk *sdkp, unsigned char *buffer)
+{
+	struct scsi_device *sdp = sdkp->device;
+	u8 type;
+
+	if (scsi_device_protection(sdp) == 0 || (buffer[12] & 1) == 0)
+		type = 0;
+	else
+		type = ((buffer[12] >> 1) & 7) + 1; /* P_TYPE 0 = Type 1 */
+
+	switch (type) {
+	case SD_DIF_TYPE0_PROTECTION:
+		sdkp->protection_type = 0;
+		break;
+
+	case SD_DIF_TYPE1_PROTECTION:
+	case SD_DIF_TYPE3_PROTECTION:
+		sdkp->protection_type = type;
+		break;
+
+	case SD_DIF_TYPE2_PROTECTION:
+		sd_printk(KERN_ERR, sdkp, "formatted with DIF Type 2 "	\
+			  "protection which is currently unsupported. "	\
+			  "Disabling disk!\n");
+		goto disable;
+
+	default:
+		sd_printk(KERN_ERR, sdkp, "formatted with unknown "	\
+			  "protection type %d. Disabling disk!\n", type);
+		goto disable;
+	}
+
+	return;
+
+disable:
+	sdkp->protection_type = 0;
+	sdkp->capacity = 0;
+}
+
 /*
  * read disk capacity
  */

@@ -1172,7 +1235,8 @@ sd_read_capacity(struct scsi_disk *sdkp,
 	unsigned char cmd[16];
 	int the_result, retries;
 	int sector_size = 0;
-	int longrc = 0;
+	/* Force READ CAPACITY(16) when PROTECT=1 */
+	int longrc = scsi_device_protection(sdkp->device) ? 1 : 0;
 	struct scsi_sense_hdr sshdr;
 	int sense_valid = 0;
 	struct scsi_device *sdp = sdkp->device;

@@ -1184,8 +1248,8 @@ repeat:
 			memset((void *) cmd, 0, 16);
 			cmd[0] = SERVICE_ACTION_IN;
 			cmd[1] = SAI_READ_CAPACITY_16;
-			cmd[13] = 12;
-			memset((void *) buffer, 0, 12);
+			cmd[13] = 13;
+			memset((void *) buffer, 0, 13);
 		} else {
 			cmd[0] = READ_CAPACITY;
 			memset((void *) &cmd[1], 0, 9);

@@ -1193,7 +1257,7 @@ repeat:
 		}
 		
 		the_result = scsi_execute_req(sdp, cmd, DMA_FROM_DEVICE,
-					      buffer, longrc ? 12 : 8, &sshdr,
+					      buffer, longrc ? 13 : 8, &sshdr,
 					      SD_TIMEOUT, SD_MAX_RETRIES);
 
 		if (media_not_present(sdkp, &sshdr))

@@ -1268,6 +1332,8 @@ repeat:
 			
 		sector_size = (buffer[8] << 24) |
 			(buffer[9] << 16) | (buffer[10] << 8) | buffer[11];
+
+		sd_read_protection_type(sdkp, buffer);
 	}	
 
 	/* Some devices return the total number of sectors, not the

@@ -1529,6 +1595,52 @@ defaults:
 	sdkp->DPOFUA = 0;
 }
 
+/*
+ * The ATO bit indicates whether the DIF application tag is available
+ * for use by the operating system.
+ */
+void sd_read_app_tag_own(struct scsi_disk *sdkp, unsigned char *buffer)
+{
+	int res, offset;
+	struct scsi_device *sdp = sdkp->device;
+	struct scsi_mode_data data;
+	struct scsi_sense_hdr sshdr;
+
+	if (sdp->type != TYPE_DISK)
+		return;
+
+	if (sdkp->protection_type == 0)
+		return;
+
+	res = scsi_mode_sense(sdp, 1, 0x0a, buffer, 36, SD_TIMEOUT,
+			      SD_MAX_RETRIES, &data, &sshdr);
+
+	if (!scsi_status_is_good(res) || !data.header_length ||
+	    data.length < 6) {
+		sd_printk(KERN_WARNING, sdkp,
+			  "getting Control mode page failed, assume no ATO\n");
+
+		if (scsi_sense_valid(&sshdr))
+			sd_print_sense_hdr(sdkp, &sshdr);
+
+		return;
+	}
+
+	offset = data.header_length + data.block_descriptor_length;
+
+	if ((buffer[offset] & 0x3f) != 0x0a) {
+		sd_printk(KERN_ERR, sdkp, "ATO Got wrong page\n");
+		return;
+	}
+
+	if ((buffer[offset + 5] & 0x80) == 0)
+		return;
+
+	sdkp->ATO = 1;
+
+	return;
+}
+
 /**
  *	sd_revalidate_disk - called the first time a new disk is seen,
  *	performs disk spin up, read_capacity, etc.

@@ -1565,6 +1677,7 @@ static int sd_revalidate_disk(struct gen
 	sdkp->write_prot = 0;
 	sdkp->WCE = 0;
 	sdkp->RCD = 0;
+	sdkp->ATO = 0;
 
 	sd_spinup_disk(sdkp);
 

@@ -1576,6 +1689,7 @@ static int sd_revalidate_disk(struct gen
 		sd_read_capacity(sdkp, buffer);
 		sd_read_write_protect_flag(sdkp, buffer);
 		sd_read_cache_type(sdkp, buffer);
+		sd_read_app_tag_own(sdkp, buffer);
 	}
 
 	/*

@@ -41,7 +41,9 @@ struct scsi_disk {
 	u32		index;
 	u8		media_present;
 	u8		write_prot;
+	u8		protection_type;/* Data Integrity Field */
 	unsigned	previous_state : 1;
+	unsigned	ATO : 1;	/* state of disk ATO bit */
 	unsigned	WCE : 1;	/* state of disk WCE bit */
 	unsigned	RCD : 1;	/* state of disk RCD bit, unused */
 	unsigned	DPOFUA : 1;	/* state of disk DPOFUA bit */

@@ -59,4 +61,25 @@ static inline struct scsi_disk *scsi_dis
 		    (sdsk)->disk->disk_name, ##a) :			\
 	sdev_printk(prefix, (sdsk)->device, fmt, ##a)
 
+/*
+ * A DIF-capable target device can be formatted with different
+ * protection schemes.  Currently 0 through 3 are defined:
+ *
+ * Type 0 is regular (unprotected) I/O
+ *
+ * Type 1 defines the contents of the guard and reference tags
+ *
+ * Type 2 defines the contents of the guard and reference tags and
+ * uses 32-byte commands to seed the latter
+ *
+ * Type 3 defines the contents of the guard tag only
+ */
+
+enum sd_dif_target_protection_types {
+	SD_DIF_TYPE0_PROTECTION = 0x0,
+	SD_DIF_TYPE1_PROTECTION = 0x1,
+	SD_DIF_TYPE2_PROTECTION = 0x2,
+	SD_DIF_TYPE3_PROTECTION = 0x3,
+};
+
 #endif /* _SCSI_DISK_H */