Commit cd063bef authored by Nicholas Bellinger's avatar Nicholas Bellinger
Browse files

target/sbc: Seperate WRITE_SAME based on UNMAP flag in sbc_ops 



This patch adds a new sbc_ops->execute_write_same_unmap() caller for use
with WRITE_SAME w/ UNMAP=1, and performs the ->execute_cmd() setup based
this bit within sbc_setup_write_same() code.

Also, makes the changes in sbc_parse_cdb() to handle a sense_reason_t
return from sbc_setup_write_same() on error.

Reported-by: default avatarChristoph Hellwig <hch@lst.de>
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: default avatarNicholas Bellinger <nab@linux-iscsi.org>
parent 1920ed61

drivers/target/target_core_sbc.c

+23 −28
Original line number Diff line number Diff line
@@ -235,26 +235,30 @@ static inline unsigned long long transport_lba_64_ext(unsigned char *cdb) 
	return ((unsigned long long)__v2) | (unsigned long long)__v1 << 32;

}



static int sbc_write_same_supported(struct se_device *dev,

		unsigned char *flags)

static sense_reason_t

sbc_setup_write_same(struct se_cmd *cmd, unsigned char *flags, struct sbc_ops *ops)

{

	if ((flags[0] & 0x04) || (flags[0] & 0x02)) {

		pr_err("WRITE_SAME PBDATA and LBDATA"

			" bits not supported for Block Discard"

			" Emulation\n");

		return -ENOSYS;

		return TCM_UNSUPPORTED_SCSI_OPCODE;

	}



	/*

	 * Currently for the emulated case we only accept

	 * tpws with the UNMAP=1 bit set.

	 * Special case for WRITE_SAME w/ UNMAP=1 that ends up getting

	 * translated into block discard requests within backend code.

	 */

	if (!(flags[0] & 0x08)) {

		pr_err("WRITE_SAME w/o UNMAP bit not"

			" supported for Block Discard Emulation\n");

		return -ENOSYS;

	if (flags[0] & 0x08) {

		if (!ops->execute_write_same_unmap)

			return TCM_UNSUPPORTED_SCSI_OPCODE;



		cmd->execute_cmd = ops->execute_write_same_unmap;

		return 0;

	}

	if (!ops->execute_write_same)

		return TCM_UNSUPPORTED_SCSI_OPCODE;



	cmd->execute_cmd = ops->execute_write_same;

	return 0;

}
@@ -418,9 +422,6 @@ sbc_parse_cdb(struct se_cmd *cmd, struct sbc_ops *ops) 
				cmd->se_cmd_flags |= SCF_FUA;

			break;

		case WRITE_SAME_32:

			if (!ops->execute_write_same)

				return TCM_UNSUPPORTED_SCSI_OPCODE;



			sectors = transport_get_sectors_32(cdb);

			if (!sectors) {

				pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not"
@@ -431,9 +432,9 @@ sbc_parse_cdb(struct se_cmd *cmd, struct sbc_ops *ops) 
			size = sbc_get_size(cmd, 1);

			cmd->t_task_lba = get_unaligned_be64(&cdb[12]);



			if (sbc_write_same_supported(dev, &cdb[10]) < 0)

				return TCM_UNSUPPORTED_SCSI_OPCODE;

			cmd->execute_cmd = ops->execute_write_same;

			ret = sbc_setup_write_same(cmd, &cdb[10], ops);

			if (ret < 0)

				return ret;

			break;

		default:

			pr_err("VARIABLE_LENGTH_CMD service action"
@@ -495,9 +496,6 @@ sbc_parse_cdb(struct se_cmd *cmd, struct sbc_ops *ops) 
		cmd->execute_cmd = ops->execute_unmap;

		break;

	case WRITE_SAME_16:

		if (!ops->execute_write_same)

			return TCM_UNSUPPORTED_SCSI_OPCODE;



		sectors = transport_get_sectors_16(cdb);

		if (!sectors) {

			pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n");
@@ -507,14 +505,11 @@ sbc_parse_cdb(struct se_cmd *cmd, struct sbc_ops *ops) 
		size = sbc_get_size(cmd, 1);

		cmd->t_task_lba = get_unaligned_be64(&cdb[2]);



		if (sbc_write_same_supported(dev, &cdb[1]) < 0)

			return TCM_UNSUPPORTED_SCSI_OPCODE;

		cmd->execute_cmd = ops->execute_write_same;

		ret = sbc_setup_write_same(cmd, &cdb[1], ops);

		if (ret < 0)

			return ret;

		break;

	case WRITE_SAME:

		if (!ops->execute_write_same)

			return TCM_UNSUPPORTED_SCSI_OPCODE;



		sectors = transport_get_sectors_10(cdb);

		if (!sectors) {

			pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n");
@@ -528,9 +523,9 @@ sbc_parse_cdb(struct se_cmd *cmd, struct sbc_ops *ops) 
		 * Follow sbcr26 with WRITE_SAME (10) and check for the existence

		 * of byte 1 bit 3 UNMAP instead of original reserved field

		 */

		if (sbc_write_same_supported(dev, &cdb[1]) < 0)

			return TCM_UNSUPPORTED_SCSI_OPCODE;

		cmd->execute_cmd = ops->execute_write_same;

		ret = sbc_setup_write_same(cmd, &cdb[1], ops);

		if (ret < 0)

			return ret;

		break;

	case VERIFY:

		size = 0;

include/target/target_core_backend.h

+1 −0
Original line number Diff line number Diff line
@@ -41,6 +41,7 @@ struct sbc_ops { 
	sense_reason_t (*execute_rw)(struct se_cmd *cmd);

	sense_reason_t (*execute_sync_cache)(struct se_cmd *cmd);

	sense_reason_t (*execute_write_same)(struct se_cmd *cmd);

	sense_reason_t (*execute_write_same_unmap)(struct se_cmd *cmd);

	sense_reason_t (*execute_unmap)(struct se_cmd *cmd);

};

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