Merge patch series "Add Command Duration Limits support"

Niklas Cassel <nks@flawful.org> says:

This series adds support for Command Duration Limits.
The series is based on linux tag: v6.4-rc1
The series can also be found in git: https://github.com/floatious/linux/commits/cdl-v7

=================
CDL in ATA / SCSI
=================
Command Duration Limits is defined in:
T13 ATA Command Set - 5 (ACS-5) and
T10 SCSI Primary Commands - 6 (SPC-6) respectively
(a simpler version of CDL is defined in T10 SPC-5).

CDL defines Duration Limits Descriptors (DLD).
7 DLDs for read commands and 7 DLDs for write commands.
Simply put, a DLD contains a limit and a policy.

A command can specify that a certain limit should be applied by setting
the DLD index field (3 bits, so 0-7) in the command itself.

The DLD index points to one of the 7 DLDs.
DLD index 0 means no descriptor, so no limit.
DLD index 1-7 means DLD 1-7.

A DLD can have a few different policies, but the two major ones are:
-Policy 0xF (abort), command will be completed with command aborted error
(ATA) or status CHECK CONDITION (SCSI), with sense data indicating that
the command timed out.
-Policy 0xD (complete-unavailable), command will be completed without
error (ATA) or status GOOD (SCSI), with sense data indicating that the
command timed out. Note that the command will not have transferred any
data to/from the device when the command timed out, even though the
command returned success.

Regardless of the CDL policy, in case of a CDL timeout, the I/O will
result in a -ETIME error to user-space.

The DLDs are defined in the CDL log page(s) and are readable and writable.
Reading and writing the CDL DLDs are outside the scope of the kernel.
If a user wants to read or write the descriptors, they can do so using a
user-space application that sends passthrough commands, such as cdl-tools:
https://github.com/westerndigitalcorporation/cdl-tools

================================
The introduction of ioprio hints
================================
What the kernel does provide, is a method to let I/O use one of the CDL DLDs
defined in the device. Note that the kernel will simply forward the DLD index
to the device, so the kernel currently does not know, nor does it need to know,
how the DLDs are defined inside the device.

The way that the CDL DLD index is supplied to the kernel is by introducing a
new 10 bit "ioprio hint" field within the existing 16 bit ioprio definition.

Currently, only 6 out of the 16 ioprio bits are in use, the remaining 10 bits
are unused, and are currently explicitly disallowed to be set by the kernel.

For now, we only add ioprio hints representing CDL DLD index 1-7. Additional
ioprio hints for other QoS features could be defined in the future.

A theoretical future work could be to make an I/O scheduler aware of these
hints. E.g. for CDL, an I/O scheduler could make use of the duration limit
in each descriptor, and take that information into account while scheduling
commands. Right now, the ioprio hints will be ignored by the I/O schedulers.

==============================
How to use CDL from user-space
==============================
Since CDL is mutually exclusive with NCQ priority
(see ncq_prio_enable and sas_ncq_prio_enable in
Documentation/ABI/testing/sysfs-block-device),
CDL has to be explicitly enabled using:
echo 1 > /sys/block/$bdev/device/cdl_enable

Since the ioprio hints are supplied through the existing I/O priority API,
it should be simple for an application to make use of the ioprio hints.

It simply has to reuse one of the new macros defined in
include/uapi/linux/ioprio.h: IOPRIO_PRIO_HINT() or IOPRIO_PRIO_VALUE_HINT(),
and supply one of the new hints defined in include/uapi/linux/ioprio.h:
IOPRIO_HINT_DEV_DURATION_LIMIT_[1-7], which indicates that the I/O should
use the corresponding CDL DLD index 1-7.

By reusing the I/O priority API, the user can both define a DLD to use per
AIO (io_uring sqe->ioprio or libaio iocb->aio_reqprio) or per-thread
(ioprio_set()).

=======
Testing
=======
With the following fio patches:
https://github.com/floatious/fio/commits/cdl

fio adds support for ioprio hints, such that CDL can be tested using e.g.:
fio --ioengine=io_uring --cmdprio_percentage=10 --cmdprio_hint=DLD_index

A simple way to test is to use a DLD with a very short duration limit,
and send large reads. Regardless of the CDL policy, in case of a CDL
timeout, the I/O will result in a -ETIME error to user-space.

We also provide a CDL test suite located in the cdl-tools repo, see:
https://github.com/westerndigitalcorporation/cdl-tools#testing-a-system-command-duration-limits-support

We have tested this patch series using:
-real hardware
-the following QEMU implementation:
https://github.com/floatious/qemu/tree/cdl
(NOTE: the QEMU implementation requires you to define the CDL policy at compile
time, so you currently need to recompile QEMU when switching between policies.)

===================
Further information
===================
For further information about CDL, see Damien's slides:

Presented at SDC 2021:
https://www.snia.org/sites/default/files/SDC/2021/pdfs/SNIA-SDC21-LeMoal-Be-On-Time-command-duration-limits-Feature-Support-in%20Linux.pdf

Presented at Lund Linux Con 2022:
https://drive.google.com/file/d/1I6ChFc0h4JY9qZdO1bY5oCAdYCSZVqWw/view?usp=sharing

================
Changes since V6
================
-Rebased series on v6.4-rc1.
-Picked up Reviewed-by tags from Hannes (Thank you Hannes!)
-Picked up Reviewed-by tag from Christoph (Thank you Christoph!)
-Changed KernelVersion from 6.4 to 6.5 for new sysfs attributes.

For older change logs, see previous patch series versions:
https://lore.kernel.org/linux-scsi/20230406113252.41211-1-nks@flawful.org/
https://lore.kernel.org/linux-scsi/20230404182428.715140-1-nks@flawful.org/
https://lore.kernel.org/linux-scsi/20230309215516.3800571-1-niklas.cassel@wdc.com/
https://lore.kernel.org/linux-scsi/20230124190308.127318-1-niklas.cassel@wdc.com/
https://lore.kernel.org/linux-scsi/20230112140412.667308-1-niklas.cassel@wdc.com/
https://lore.kernel.org/linux-scsi/20221208105947.2399894-1-niklas.cassel@wdc.com/

Link: https://lore.kernel.org/r/20230511011356.227789-1-nks@flawful.org
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

9 files changed, 301 insertions, 35 deletions

diff --git a/drivers/scsi/scsi.c b/drivers/scsi/scsi.c
index 09ef0b31dfc0..c4bf99a842f3 100644
--- a/drivers/scsi/scsi.c
+++ b/drivers/scsi/scsi.c
@@ -504,18 +504,22 @@ void scsi_attach_vpd(struct scsi_device *sdev)
 }
 
 /**
- * scsi_report_opcode - Find out if a given command opcode is supported
+ * scsi_report_opcode - Find out if a given command is supported
  * @sdev:	scsi device to query
  * @buffer:	scratch buffer (must be at least 20 bytes long)
  * @len:	length of buffer
- * @opcode:	opcode for command to look up
- *
- * Uses the REPORT SUPPORTED OPERATION CODES to look up the given
- * opcode. Returns -EINVAL if RSOC fails, 0 if the command opcode is
- * unsupported and 1 if the device claims to support the command.
+ * @opcode:	opcode for the command to look up
+ * @sa:		service action for the command to look up
+ *
+ * Uses the REPORT SUPPORTED OPERATION CODES to check support for the
+ * command identified with @opcode and @sa. If the command does not
+ * have a service action, @sa must be 0. Returns -EINVAL if RSOC fails,
+ * 0 if the command is not supported and 1 if the device claims to
+ * support the command.
  */
 int scsi_report_opcode(struct scsi_device *sdev, unsigned char *buffer,
-		       unsigned int len, unsigned char opcode)
+		       unsigned int len, unsigned char opcode,
+		       unsigned short sa)
 {
 	unsigned char cmd[16];
 	struct scsi_sense_hdr sshdr;
@@ -539,8 +543,14 @@ int scsi_report_opcode(struct scsi_device *sdev, unsigned char *buffer,
 	memset(cmd, 0, 16);
 	cmd[0] = MAINTENANCE_IN;
 	cmd[1] = MI_REPORT_SUPPORTED_OPERATION_CODES;
-	cmd[2] = 1;		/* One command format */
-	cmd[3] = opcode;
+	if (!sa) {
+		cmd[2] = 1;	/* One command format */
+		cmd[3] = opcode;
+	} else {
+		cmd[2] = 3;	/* One command format with service action */
+		cmd[3] = opcode;
+		put_unaligned_be16(sa, &cmd[4]);
+	}
 	put_unaligned_be32(request_len, &cmd[6]);
 	memset(buffer, 0, len);
 
@@ -560,6 +570,149 @@ int scsi_report_opcode(struct scsi_device *sdev, unsigned char *buffer,
 }
 EXPORT_SYMBOL(scsi_report_opcode);
 
+#define SCSI_CDL_CHECK_BUF_LEN	64
+
+static bool scsi_cdl_check_cmd(struct scsi_device *sdev, u8 opcode, u16 sa,
+			       unsigned char *buf)
+{
+	int ret;
+	u8 cdlp;
+
+	/* Check operation code */
+	ret = scsi_report_opcode(sdev, buf, SCSI_CDL_CHECK_BUF_LEN, opcode, sa);
+	if (ret <= 0)
+		return false;
+
+	if ((buf[1] & 0x03) != 0x03)
+		return false;
+
+	/* See SPC-6, one command format of REPORT SUPPORTED OPERATION CODES */
+	cdlp = (buf[1] & 0x18) >> 3;
+	if (buf[0] & 0x01) {
+		/* rwcdlp == 1 */
+		switch (cdlp) {
+		case 0x01:
+			/* T2A page */
+			return true;
+		case 0x02:
+			/* T2B page */
+			return true;
+		}
+	} else {
+		/* rwcdlp == 0 */
+		switch (cdlp) {
+		case 0x01:
+			/* A page */
+			return true;
+		case 0x02:
+			/* B page */
+			return true;
+		}
+	}
+
+	return false;
+}
+
+/**
+ * scsi_cdl_check - Check if a SCSI device supports Command Duration Limits
+ * @sdev: The device to check
+ */
+void scsi_cdl_check(struct scsi_device *sdev)
+{
+	bool cdl_supported;
+	unsigned char *buf;
+
+	buf = kmalloc(SCSI_CDL_CHECK_BUF_LEN, GFP_KERNEL);
+	if (!buf) {
+		sdev->cdl_supported = 0;
+		return;
+	}
+
+	/* Check support for READ_16, WRITE_16, READ_32 and WRITE_32 commands */
+	cdl_supported =
+		scsi_cdl_check_cmd(sdev, READ_16, 0, buf) ||
+		scsi_cdl_check_cmd(sdev, WRITE_16, 0, buf) ||
+		scsi_cdl_check_cmd(sdev, VARIABLE_LENGTH_CMD, READ_32, buf) ||
+		scsi_cdl_check_cmd(sdev, VARIABLE_LENGTH_CMD, WRITE_32, buf);
+	if (cdl_supported) {
+		/*
+		 * We have CDL support: force the use of READ16/WRITE16.
+		 * READ32 and WRITE32 will be used for devices that support
+		 * the T10_PI_TYPE2_PROTECTION protection type.
+		 */
+		sdev->use_16_for_rw = 1;
+		sdev->use_10_for_rw = 0;
+
+		sdev->cdl_supported = 1;
+	} else {
+		sdev->cdl_supported = 0;
+	}
+
+	kfree(buf);
+}
+
+/**
+ * scsi_cdl_enable - Enable or disable a SCSI device supports for Command
+ *                   Duration Limits
+ * @sdev: The target device
+ * @enable: the target state
+ */
+int scsi_cdl_enable(struct scsi_device *sdev, bool enable)
+{
+	struct scsi_mode_data data;
+	struct scsi_sense_hdr sshdr;
+	struct scsi_vpd *vpd;
+	bool is_ata = false;
+	char buf[64];
+	int ret;
+
+	if (!sdev->cdl_supported)
+		return -EOPNOTSUPP;
+
+	rcu_read_lock();
+	vpd = rcu_dereference(sdev->vpd_pg89);
+	if (vpd)
+		is_ata = true;
+	rcu_read_unlock();
+
+	/*
+	 * For ATA devices, CDL needs to be enabled with a SET FEATURES command.
+	 */
+	if (is_ata) {
+		char *buf_data;
+		int len;
+
+		ret = scsi_mode_sense(sdev, 0x08, 0x0a, 0xf2, buf, sizeof(buf),
+				      5 * HZ, 3, &data, NULL);
+		if (ret)
+			return -EINVAL;
+
+		/* Enable CDL using the ATA feature page */
+		len = min_t(size_t, sizeof(buf),
+			    data.length - data.header_length -
+			    data.block_descriptor_length);
+		buf_data = buf + data.header_length +
+			data.block_descriptor_length;
+		if (enable)
+			buf_data[4] = 0x02;
+		else
+			buf_data[4] = 0;
+
+		ret = scsi_mode_select(sdev, 1, 0, buf_data, len, 5 * HZ, 3,
+				       &data, &sshdr);
+		if (ret) {
+			if (scsi_sense_valid(&sshdr))
+				scsi_print_sense_hdr(sdev,
+					dev_name(&sdev->sdev_gendev), &sshdr);
+			return ret;
+		}
+	}
+
+	sdev->cdl_enable = enable;
+
+	return 0;
+}
+
 /**
  * scsi_device_get  -  get an additional reference to a scsi_device
  * @sdev:	device to get a reference to
diff --git a/drivers/scsi/scsi_error.c b/drivers/scsi/scsi_error.c
index 3ec8bfd4090f..c67cdcdc3ba8 100644
--- a/drivers/scsi/scsi_error.c
+++ b/drivers/scsi/scsi_error.c
@@ -536,6 +536,7 @@ static inline void set_scsi_ml_byte(struct scsi_cmnd *cmd, u8 status)
  */
 enum scsi_disposition scsi_check_sense(struct scsi_cmnd *scmd)
 {
+	struct request *req = scsi_cmd_to_rq(scmd);
 	struct scsi_device *sdev = scmd->device;
 	struct scsi_sense_hdr sshdr;
 
@@ -595,6 +596,22 @@ enum scsi_disposition scsi_check_sense(struct scsi_cmnd *scmd)
 		if (sshdr.asc == 0x10) /* DIF */
 			return SUCCESS;
 
+		/*
+		 * Check aborts due to command duration limit policy:
+		 * ABORTED COMMAND additional sense code with the
+		 * COMMAND TIMEOUT BEFORE PROCESSING or
+		 * COMMAND TIMEOUT DURING PROCESSING or
+		 * COMMAND TIMEOUT DURING PROCESSING DUE TO ERROR RECOVERY
+		 * additional sense code qualifiers.
+		 */
+		if (sshdr.asc == 0x2e &&
+		    sshdr.ascq >= 0x01 && sshdr.ascq <= 0x03) {
+			set_scsi_ml_byte(scmd, SCSIML_STAT_DL_TIMEOUT);
+			req->cmd_flags |= REQ_FAILFAST_DEV;
+			req->rq_flags |= RQF_QUIET;
+			return SUCCESS;
+		}
+
 		if (sshdr.asc == 0x44 && sdev->sdev_bflags & BLIST_RETRY_ITF)
 			return ADD_TO_MLQUEUE;
 		if (sshdr.asc == 0xc1 && sshdr.ascq == 0x01 &&
@@ -691,6 +708,14 @@ enum scsi_disposition scsi_check_sense(struct scsi_cmnd *scmd)
 		}
 		return SUCCESS;
 
+	case COMPLETED:
+		if (sshdr.asc == 0x55 && sshdr.ascq == 0x0a) {
+			set_scsi_ml_byte(scmd, SCSIML_STAT_DL_TIMEOUT);
+			req->cmd_flags |= REQ_FAILFAST_DEV;
+			req->rq_flags |= RQF_QUIET;
+		}
+		return SUCCESS;
+
 	default:
 		return SUCCESS;
 	}
@@ -785,6 +810,14 @@ static enum scsi_disposition scsi_eh_completed_normally(struct scsi_cmnd *scmd)
 	switch (get_status_byte(scmd)) {
 	case SAM_STAT_GOOD:
 		scsi_handle_queue_ramp_up(scmd->device);
+		if (scmd->sense_buffer && SCSI_SENSE_VALID(scmd))
+			/*
+			 * If we have sense data, call scsi_check_sense() in
+			 * order to set the correct SCSI ML byte (if any).
+			 * No point in checking the return value, since the
+			 * command has already completed successfully.
+			 */
+			scsi_check_sense(scmd);
 		fallthrough;
 	case SAM_STAT_COMMAND_TERMINATED:
 		return SUCCESS;
@@ -1807,6 +1840,10 @@ bool scsi_noretry_cmd(struct scsi_cmnd *scmd)
 		return !!(req->cmd_flags & REQ_FAILFAST_DRIVER);
 	}
 
+	/* Never retry commands aborted due to a duration limit timeout */
+	if (scsi_ml_byte(scmd->result) == SCSIML_STAT_DL_TIMEOUT)
+		return true;
+
 	if (!scsi_status_is_check_condition(scmd->result))
 		return false;
 
@@ -1966,6 +2003,14 @@ enum scsi_disposition scsi_decide_disposition(struct scsi_cmnd *scmd)
 		if (scmd->cmnd[0] == REPORT_LUNS)
 			scmd->device->sdev_target->expecting_lun_change = 0;
 		scsi_handle_queue_ramp_up(scmd->device);
+		if (scmd->sense_buffer && SCSI_SENSE_VALID(scmd))
+			/*
+			 * If we have sense data, call scsi_check_sense() in
+			 * order to set the correct SCSI ML byte (if any).
+			 * No point in checking the return value, since the
+			 * command has already completed successfully.
+			 */
+			scsi_check_sense(scmd);
 		fallthrough;
 	case SAM_STAT_COMMAND_TERMINATED:
 		return SUCCESS;
@@ -2165,7 +2210,8 @@ void scsi_eh_flush_done_q(struct list_head *done_q)
 			 * scsi_eh_get_sense), scmd->result is already
 			 * set, do not set DID_TIME_OUT.
 			 */
-			if (!scmd->result)
+			if (!scmd->result &&
+			    !(scmd->flags & SCMD_FORCE_EH_SUCCESS))
 				scmd->result |= (DID_TIME_OUT << 16);
 			SCSI_LOG_ERROR_RECOVERY(3,
 				scmd_printk(KERN_INFO, scmd,
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index e1468483ac7e..25489fbd94c6 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -578,11 +578,6 @@ static bool scsi_end_request(struct request *req, blk_status_t error,
 	return false;
 }
 
-static inline u8 get_scsi_ml_byte(int result)
-{
-	return (result >> 8) & 0xff;
-}
-
 /**
  * scsi_result_to_blk_status - translate a SCSI result code into blk_status_t
  * @result:	scsi error code
@@ -595,7 +590,7 @@ static blk_status_t scsi_result_to_blk_status(int result)
 	 * Check the scsi-ml byte first in case we converted a host or status
 	 * byte.
 	 */
-	switch (get_scsi_ml_byte(result)) {
+	switch (scsi_ml_byte(result)) {
 	case SCSIML_STAT_OK:
 		break;
 	case SCSIML_STAT_RESV_CONFLICT:
@@ -606,6 +601,8 @@ static blk_status_t scsi_result_to_blk_status(int result)
 		return BLK_STS_MEDIUM;
 	case SCSIML_STAT_TGT_FAILURE:
 		return BLK_STS_TARGET;
+	case SCSIML_STAT_DL_TIMEOUT:
+		return BLK_STS_DURATION_LIMIT;
 	}
 
 	switch (host_byte(result)) {
@@ -803,6 +800,8 @@ static void scsi_io_completion_action(struct scsi_cmnd *cmd, int result)
 				blk_stat = BLK_STS_ZONE_OPEN_RESOURCE;
 			}
 			break;
+		case COMPLETED:
+			fallthrough;
 		default:
 			action = ACTION_FAIL;
 			break;
@@ -2149,6 +2148,7 @@ EXPORT_SYMBOL_GPL(scsi_mode_select);
  *	@sdev:	SCSI device to be queried
  *	@dbd:	set to prevent mode sense from returning block descriptors
  *	@modepage: mode page being requested
+ *	@subpage: sub-page of the mode page being requested
  *	@buffer: request buffer (may not be smaller than eight bytes)
  *	@len:	length of request buffer.
  *	@timeout: command timeout
@@ -2160,7 +2160,7 @@ EXPORT_SYMBOL_GPL(scsi_mode_select);
  *	Returns zero if successful, or a negative error number on failure
  */
 int
-scsi_mode_sense(struct scsi_device *sdev, int dbd, int modepage,
+scsi_mode_sense(struct scsi_device *sdev, int dbd, int modepage, int subpage,
 		  unsigned char *buffer, int len, int timeout, int retries,
 		  struct scsi_mode_data *data, struct scsi_sense_hdr *sshdr)
 {
@@ -2180,6 +2180,7 @@ scsi_mode_sense(struct scsi_device *sdev, int dbd, int modepage,
 	dbd = sdev->set_dbd_for_ms ? 8 : dbd;
 	cmd[1] = dbd & 0x18;	/* allows DBD and LLBA bits */
 	cmd[2] = modepage;
+	cmd[3] = subpage;
 
 	sshdr = exec_args.sshdr;
 
diff --git a/drivers/scsi/scsi_priv.h b/drivers/scsi/scsi_priv.h
index 96284a0e13fe..f42388ecb024 100644
--- a/drivers/scsi/scsi_priv.h
+++ b/drivers/scsi/scsi_priv.h
@@ -27,8 +27,14 @@ enum scsi_ml_status {
 	SCSIML_STAT_NOSPC		= 0x02,	/* Space allocation on the dev failed */
 	SCSIML_STAT_MED_ERROR		= 0x03,	/* Medium error */
 	SCSIML_STAT_TGT_FAILURE		= 0x04,	/* Permanent target failure */
+	SCSIML_STAT_DL_TIMEOUT		= 0x05, /* Command Duration Limit timeout */
 };
 
+static inline u8 scsi_ml_byte(int result)
+{
+	return (result >> 8) & 0xff;
+}
+
 /*
  * Scsi Error Handler Flags
  */
diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c
index d217be323cc6..aa13feb17c62 100644
--- a/drivers/scsi/scsi_scan.c
+++ b/drivers/scsi/scsi_scan.c
@@ -1087,6 +1087,8 @@ static int scsi_add_lun(struct scsi_device *sdev, unsigned char *inq_result,
 	if (sdev->scsi_level >= SCSI_3)
 		scsi_attach_vpd(sdev);
 
+	scsi_cdl_check(sdev);
+
 	sdev->max_queue_depth = sdev->queue_depth;
 	WARN_ON_ONCE(sdev->max_queue_depth > sdev->budget_map.depth);
 	sdev->sdev_bflags = *bflags;
@@ -1624,6 +1626,7 @@ void scsi_rescan_device(struct device *dev)
 	device_lock(dev);
 
 	scsi_attach_vpd(sdev);
+	scsi_cdl_check(sdev);
 
 	if (sdev->handler && sdev->handler->rescan)
 		sdev->handler->rescan(sdev);
diff --git a/drivers/scsi/scsi_sysfs.c b/drivers/scsi/scsi_sysfs.c
index 603e8fcfcb8a..60317676e45f 100644
--- a/drivers/scsi/scsi_sysfs.c
+++ b/drivers/scsi/scsi_sysfs.c
@@ -670,6 +670,7 @@ sdev_rd_attr (scsi_level, "%d\n");
 sdev_rd_attr (vendor, "%.8s\n");
 sdev_rd_attr (model, "%.16s\n");
 sdev_rd_attr (rev, "%.4s\n");
+sdev_rd_attr (cdl_supported, "%d\n");
 
 static ssize_t
 sdev_show_device_busy(struct device *dev, struct device_attribute *attr,
@@ -1221,6 +1222,33 @@ static DEVICE_ATTR(queue_ramp_up_period, S_IRUGO | S_IWUSR,
 		   sdev_show_queue_ramp_up_period,
 		   sdev_store_queue_ramp_up_period);
 
+static ssize_t sdev_show_cdl_enable(struct device *dev,
+				    struct device_attribute *attr, char *buf)
+{
+	struct scsi_device *sdev = to_scsi_device(dev);
+
+	return sysfs_emit(buf, "%d\n", (int)sdev->cdl_enable);
+}
+
+static ssize_t sdev_store_cdl_enable(struct device *dev,
+				     struct device_attribute *attr,
+				     const char *buf, size_t count)
+{
+	int ret;
+	bool v;
+
+	if (kstrtobool(buf, &v))
+		return -EINVAL;
+
+	ret = scsi_cdl_enable(to_scsi_device(dev), v);
+	if (ret)
+		return ret;
+
+	return count;
+}
+static DEVICE_ATTR(cdl_enable, S_IRUGO | S_IWUSR,
+		   sdev_show_cdl_enable, sdev_store_cdl_enable);
+
 static umode_t scsi_sdev_attr_is_visible(struct kobject *kobj,
 					 struct attribute *attr, int i)
 {
@@ -1300,6 +1328,8 @@ static struct attribute *scsi_sdev_attrs[] = {
 	&dev_attr_preferred_path.attr,
 #endif
 	&dev_attr_queue_ramp_up_period.attr,
+	&dev_attr_cdl_supported.attr,
+	&dev_attr_cdl_enable.attr,
 	REF_EVT(media_change),
 	REF_EVT(inquiry_change_reported),
 	REF_EVT(capacity_change_reported),
diff --git a/drivers/scsi/scsi_transport_sas.c b/drivers/scsi/scsi_transport_sas.c
index 74b99f2b0b74..d704c484a251 100644
--- a/drivers/scsi/scsi_transport_sas.c
+++ b/drivers/scsi/scsi_transport_sas.c
@@ -1245,7 +1245,7 @@ int sas_read_port_mode_page(struct scsi_device *sdev)
 	if (!buffer)
 		return -ENOMEM;
 
-	error = scsi_mode_sense(sdev, 1, 0x19, buffer, BUF_SIZE, 30*HZ, 3,
+	error = scsi_mode_sense(sdev, 1, 0x19, 0, buffer, BUF_SIZE, 30*HZ, 3,
 				&mode_data, NULL);
 
 	if (error)
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index 5247abe4f266..84edbc0a5747 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -184,7 +184,7 @@ cache_type_store(struct device *dev, struct device_attribute *attr,
 		return count;
 	}
 
-	if (scsi_mode_sense(sdp, 0x08, 8, buffer, sizeof(buffer), SD_TIMEOUT,
+	if (scsi_mode_sense(sdp, 0x08, 8, 0, buffer, sizeof(buffer), SD_TIMEOUT,
 			    sdkp->max_retries, &data, NULL))
 		return -EINVAL;
 	len = min_t(size_t, sizeof(buffer), data.length - data.header_length -
@@ -1042,13 +1042,14 @@ static blk_status_t sd_setup_flush_cmnd(struct scsi_cmnd *cmd)
 
 static blk_status_t sd_setup_rw32_cmnd(struct scsi_cmnd *cmd, bool write,
 				       sector_t lba, unsigned int nr_blocks,
-				       unsigned char flags)
+				       unsigned char flags, unsigned int dld)
 {
 	cmd->cmd_len = SD_EXT_CDB_SIZE;
 	cmd->cmnd[0]  = VARIABLE_LENGTH_CMD;
 	cmd->cmnd[7]  = 0x18; /* Additional CDB len */
 	cmd->cmnd[9]  = write ? WRITE_32 : READ_32;
 	cmd->cmnd[10] = flags;
+	cmd->cmnd[11] = dld & 0x07;
 	put_unaligned_be64(lba, &cmd->cmnd[12]);
 	put_unaligned_be32(lba, &cmd->cmnd[20]); /* Expected Indirect LBA */
 	put_unaligned_be32(nr_blocks, &cmd->cmnd[28]);
@@ -1058,12 +1059,12 @@ static blk_status_t sd_setup_rw32_cmnd(struct scsi_cmnd *cmd, bool write,
 
 static blk_status_t sd_setup_rw16_cmnd(struct scsi_cmnd *cmd, bool write,
 				       sector_t lba, unsigned int nr_blocks,
-				       unsigned char flags)
+				       unsigned char flags, unsigned int dld)
 {
 	cmd->cmd_len  = 16;
 	cmd->cmnd[0]  = write ? WRITE_16 : READ_16;
-	cmd->cmnd[1]  = flags;
-	cmd->cmnd[14] = 0;
+	cmd->cmnd[1]  = flags | ((dld >> 2) & 0x01);
+	cmd->cmnd[14] = (dld & 0x03) << 6;
 	cmd->cmnd[15] = 0;
 	put_unaligned_be64(lba, &cmd->cmnd[2]);
 	put_unaligned_be32(nr_blocks, &cmd->cmnd[10]);
@@ -1115,6 +1116,31 @@ static blk_status_t sd_setup_rw6_cmnd(struct scsi_cmnd *cmd, bool write,
 	return BLK_STS_OK;
 }
 
+/*
+ * Check if a command has a duration limit set. If it does, and the target
+ * device supports CDL and the feature is enabled, return the limit
+ * descriptor index to use. Return 0 (no limit) otherwise.
+ */
+static int sd_cdl_dld(struct scsi_disk *sdkp, struct scsi_cmnd *scmd)
+{
+	struct scsi_device *sdp = sdkp->device;
+	int hint;
+
+	if (!sdp->cdl_supported || !sdp->cdl_enable)
+		return 0;
+
+	/*
+	 * Use "no limit" if the request ioprio does not specify a duration
+	 * limit hint.
+	 */
+	hint = IOPRIO_PRIO_HINT(req_get_ioprio(scsi_cmd_to_rq(scmd)));
+	if (hint < IOPRIO_HINT_DEV_DURATION_LIMIT_1 ||
+	    hint > IOPRIO_HINT_DEV_DURATION_LIMIT_7)
+		return 0;
+
+	return (hint - IOPRIO_HINT_DEV_DURATION_LIMIT_1) + 1;
+}
+
 static blk_status_t sd_setup_read_write_cmnd(struct scsi_cmnd *cmd)
 {
 	struct request *rq = scsi_cmd_to_rq(cmd);
@@ -1126,6 +1152,7 @@ static blk_status_t sd_setup_read_write_cmnd(struct scsi_cmnd *cmd)
 	unsigned int mask = logical_to_sectors(sdp, 1) - 1;
 	bool write = rq_data_dir(rq) == WRITE;
 	unsigned char protect, fua;
+	unsigned int dld;
 	blk_status_t ret;
 	unsigned int dif;
 	bool dix;
@@ -1175,6 +1202,7 @@ static blk_status_t sd_setup_read_write_cmnd(struct scsi_cmnd *cmd)
 	fua = rq->cmd_flags & REQ_FUA ? 0x8 : 0;
 	dix = scsi_prot_sg_count(cmd);
 	dif = scsi_host_dif_capable(cmd->device->host, sdkp->protection_type);
+	dld = sd_cdl_dld(sdkp, cmd);
 
 	if (dif || dix)
 		protect = sd_setup_protect_cmnd(cmd, dix, dif);
@@ -1183,10 +1211,10 @@ static blk_status_t sd_setup_read_write_cmnd(struct scsi_cmnd *cmd)
 
 	if (protect && sdkp->protection_type == T10_PI_TYPE2_PROTECTION) {
 		ret = sd_setup_rw32_cmnd(cmd, write, lba, nr_blocks,
-					 protect | fua);
+					 protect | fua, dld);
 	} else if (sdp->use_16_for_rw || (nr_blocks > 0xffff)) {
 		ret = sd_setup_rw16_cmnd(cmd, write, lba, nr_blocks,
-					 protect | fua);
+					 protect | fua, dld);
 	} else if ((nr_blocks > 0xff) || (lba > 0x1fffff) ||
 		   sdp->use_10_for_rw || protect) {
 		ret = sd_setup_rw10_cmnd(cmd, write, lba, nr_blocks,
@@ -2683,9 +2711,8 @@ sd_do_mode_sense(struct scsi_disk *sdkp, int dbd, int modepage,
 	if (sdkp->device->use_10_for_ms && len < 8)
 		len = 8;
 
-	return scsi_mode_sense(sdkp->device, dbd, modepage, buffer, len,
-			       SD_TIMEOUT, sdkp->max_retries, data,
-			       sshdr);
+	return scsi_mode_sense(sdkp->device, dbd, modepage, 0, buffer, len,
+			       SD_TIMEOUT, sdkp->max_retries, data, sshdr);
 }
 
 /*
@@ -2942,7 +2969,7 @@ static void sd_read_app_tag_own(struct scsi_disk *sdkp, unsigned char *buffer)
 	if (sdkp->protection_type == 0)
 		return;
 
-	res = scsi_mode_sense(sdp, 1, 0x0a, buffer, 36, SD_TIMEOUT,
+	res = scsi_mode_sense(sdp, 1, 0x0a, 0, buffer, 36, SD_TIMEOUT,
 			      sdkp->max_retries, &data, &sshdr);
 
 	if (res < 0 || !data.header_length ||
@@ -3131,7 +3158,7 @@ static void sd_read_write_same(struct scsi_disk *sdkp, unsigned char *buffer)
 		return;
 	}
 
-	if (scsi_report_opcode(sdev, buffer, SD_BUF_SIZE, INQUIRY) < 0) {
+	if (scsi_report_opcode(sdev, buffer, SD_BUF_SIZE, INQUIRY, 0) < 0) {
 		struct scsi_vpd *vpd;
 
 		sdev->no_report_opcodes = 1;
@@ -3147,10 +3174,10 @@ static void sd_read_write_same(struct scsi_disk *sdkp, unsigned char *buffer)
 		rcu_read_unlock();
 	}
 
-	if (scsi_report_opcode(sdev, buffer, SD_BUF_SIZE, WRITE_SAME_16) == 1)
+	if (scsi_report_opcode(sdev, buffer, SD_BUF_SIZE, WRITE_SAME_16, 0) == 1)
 		sdkp->ws16 = 1;
 
-	if (scsi_report_opcode(sdev, buffer, SD_BUF_SIZE, WRITE_SAME) == 1)
+	if (scsi_report_opcode(sdev, buffer, SD_BUF_SIZE, WRITE_SAME, 0) == 1)
 		sdkp->ws10 = 1;
 }
 
@@ -3162,9 +3189,9 @@ static void sd_read_security(struct scsi_disk *sdkp, unsigned char *buffer)
 		return;
 
 	if (scsi_report_opcode(sdev, buffer, SD_BUF_SIZE,
-			SECURITY_PROTOCOL_IN) == 1 &&
+			SECURITY_PROTOCOL_IN, 0) == 1 &&
 	    scsi_report_opcode(sdev, buffer, SD_BUF_SIZE,
-			SECURITY_PROTOCOL_OUT) == 1)
+			SECURITY_PROTOCOL_OUT, 0) == 1)
 		sdkp->security = 1;
 }
 
diff --git a/drivers/scsi/sr.c b/drivers/scsi/sr.c
index 12869e6d4ebd..cd5b08689c1a 100644
--- a/drivers/scsi/sr.c
+++ b/drivers/scsi/sr.c
@@ -825,7 +825,7 @@ static int get_capabilities(struct scsi_cd *cd)
 	scsi_test_unit_ready(cd->device, SR_TIMEOUT, MAX_RETRIES, &sshdr);
 
 	/* ask for mode page 0x2a */
-	rc = scsi_mode_sense(cd->device, 0, 0x2a, buffer, ms_len,
+	rc = scsi_mode_sense(cd->device, 0, 0x2a, 0, buffer, ms_len,
 			     SR_TIMEOUT, 3, &data, NULL);
 
 	if (rc < 0 || data.length > ms_len ||