[PATCH v6 17/19] ata: libata: add ATA feature control sub-page translation

Niklas Cassel
2023-04-06T11:50:05Z

From: Damien Le Moal <damien.lemoal@opensource.wdc.com>

Add support for the ATA feature control sub-page of the control mode
page to enable/disable the command duration limits feature using the
cdl_ctrl field of the ATA feature control sub-page.

Both mode sense and mode select translation are supported. For mode
sense, the ata device flag ATA_DFLAG_CDL_ENABLED is used to cache the
status of the command duration limits feature. Enabling this feature is
done using a SET FEATURES command with a cdl action set to 1 when the
page cdl_ctrl field value is 0x2 (T2A and T2B pages supported). If this
field is 0, CDL is disabled using the SET FEATURES command with a cdl
action set to 0.

Since a device CDL and NCQ priority features should not be used
simultaneously, ata_mselect_control_ata_feature() returns an error when
attempting to enable CDL with the device priority feature enabled.
Conversely, the function ata_ncq_prio_enable_store() used to enable the
use of the device NCQ priority feature through sysfs is modified to
return an error if the device CDL feature is enabled.

Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Co-developed-by: Niklas Cassel <niklas.cassel@wdc.com>
Signed-off-by: Niklas Cassel <niklas.cassel@wdc.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
---
drivers/ata/libata-core.c | 40 ++++++++-
drivers/ata/libata-sata.c | 11 ++-
drivers/ata/libata-scsi.c | 167 ++++++++++++++++++++++++++++++++------
include/linux/ata.h | 3 +
include/linux/libata.h | 1 +
5 files changed, 193 insertions(+), 29 deletions(-)

diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 78e53f4fa741..62e100fa90e2 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -2371,13 +2371,15 @@ static void ata_dev_config_cdl(struct ata_device *dev)
{
struct ata_port *ap = dev->link->ap;
unsigned int err_mask;
+ bool cdl_enabled;
u64 val;

if (ata_id_major_version(dev->id) < 12)
goto not_supported;

if (!ata_log_supported(dev, ATA_LOG_IDENTIFY_DEVICE) ||
- !ata_identify_page_supported(dev, ATA_LOG_SUPPORTED_CAPABILITIES))
+ !ata_identify_page_supported(dev, ATA_LOG_SUPPORTED_CAPABILITIES) ||
+ !ata_identify_page_supported(dev, ATA_LOG_CURRENT_SETTINGS))
goto not_supported;

err_mask = ata_read_log_page(dev, ATA_LOG_IDENTIFY_DEVICE,
@@ -2396,6 +2398,40 @@ static void ata_dev_config_cdl(struct ata_device *dev)
ata_dev_warn(dev,
"Command duration guideline is not supported\n");

+ /*
+ * If CDL is marked as enabled, make sure the feature is enabled too.
+ * Conversely, if CDL is disabled, make sure the feature is turned off.
+ */
+ err_mask = ata_read_log_page(dev, ATA_LOG_IDENTIFY_DEVICE,
+ ATA_LOG_CURRENT_SETTINGS,
+ ap->sector_buf, 1);
+ if (err_mask)
+ goto not_supported;
+
+ val = get_unaligned_le64(&ap->sector_buf[8]);
+ cdl_enabled = val & BIT_ULL(63) && val & BIT_ULL(21);
+ if (dev->flags & ATA_DFLAG_CDL_ENABLED) {
+ if (!cdl_enabled) {
+ /* Enable CDL on the device */
+ err_mask = ata_dev_set_feature(dev, SETFEATURES_CDL, 1);
+ if (err_mask) {
+ ata_dev_err(dev,
+ "Enable CDL feature failed\n");
+ goto not_supported;
+ }
+ }
+ } else {
+ if (cdl_enabled) {
+ /* Disable CDL on the device */
+ err_mask = ata_dev_set_feature(dev, SETFEATURES_CDL, 0);
+ if (err_mask) {
+ ata_dev_err(dev,
+ "Disable CDL feature failed\n");
+ goto not_supported;
+ }
+ }
+ }
+
/*
* Command duration limits is supported: cache the CDL log page 18h
* (command duration descriptors).
@@ -2412,7 +2448,7 @@ static void ata_dev_config_cdl(struct ata_device *dev)
return;

not_supported:
- dev->flags &= ~ATA_DFLAG_CDL;
+ dev->flags &= ~(ATA_DFLAG_CDL | ATA_DFLAG_CDL_ENABLED);
}

static int ata_dev_config_lba(struct ata_device *dev)
diff --git a/drivers/ata/libata-sata.c b/drivers/ata/libata-sata.c
index f3e7396e3191..57cb33060c9d 100644
--- a/drivers/ata/libata-sata.c
+++ b/drivers/ata/libata-sata.c
@@ -907,10 +907,17 @@ static ssize_t ata_ncq_prio_enable_store(struct device *device,
goto unlock;
}

- if (input)
+ if (input) {
+ if (dev->flags & ATA_DFLAG_CDL_ENABLED) {
+ ata_dev_err(dev,
+ "CDL must be disabled to enable NCQ priority\n");
+ rc = -EINVAL;
+ goto unlock;
+ }
dev->flags |= ATA_DFLAG_NCQ_PRIO_ENABLED;
- else
+ } else {
dev->flags &= ~ATA_DFLAG_NCQ_PRIO_ENABLED;
+ }

unlock:
spin_unlock_irq(ap->lock);
diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
index 9315a4c01276..8dde1cede5ca 100644
--- a/drivers/ata/libata-scsi.c
+++ b/drivers/ata/libata-scsi.c
@@ -58,6 +58,8 @@ static struct ata_device *__ata_scsi_find_dev(struct ata_port *ap,
#define CDL_T2A_SUB_MPAGE 0x07
#define CDL_T2B_SUB_MPAGE 0x08
#define CDL_T2_SUB_MPAGE_LEN 232
+#define ATA_FEATURE_SUB_MPAGE 0xf2
+#define ATA_FEATURE_SUB_MPAGE_LEN 16

static const u8 def_rw_recovery_mpage[RW_RECOVERY_MPAGE_LEN] = {
RW_RECOVERY_MPAGE,
@@ -2286,6 +2288,31 @@ static unsigned int ata_msense_control_spgt2(struct ata_device *dev, u8 *buf,
return CDL_T2_SUB_MPAGE_LEN;
}

+/*
+ * Simulate MODE SENSE control mode page, sub-page f2h
+ * (ATA feature control mode page).
+ */
+static unsigned int ata_msense_control_ata_feature(struct ata_device *dev,
+ u8 *buf)
+{
+ /* PS=0, SPF=1 */
+ buf[0] = CONTROL_MPAGE | (1 << 6);
+ buf[1] = ATA_FEATURE_SUB_MPAGE;
+
+ /*
+ * The first four bytes of ATA Feature Control mode page are a header.
+ * The PAGE LENGTH field is the size of the page excluding the header.
+ */
+ put_unaligned_be16(ATA_FEATURE_SUB_MPAGE_LEN - 4, &buf[2]);
+
+ if (dev->flags & ATA_DFLAG_CDL)
+ buf[4] = 0x02; /* Support T2A and T2B pages */
+ else
+ buf[4] = 0;
+
+ return ATA_FEATURE_SUB_MPAGE_LEN;
+}
+
/**
* ata_msense_control - Simulate MODE SENSE control mode page
* @dev: ATA device of interest
@@ -2309,10 +2336,13 @@ static unsigned int ata_msense_control(struct ata_device *dev, u8 *buf,
case CDL_T2A_SUB_MPAGE:
case CDL_T2B_SUB_MPAGE:
return ata_msense_control_spgt2(dev, buf, spg);
+ case ATA_FEATURE_SUB_MPAGE:
+ return ata_msense_control_ata_feature(dev, buf);
case ALL_SUB_MPAGES:
n = ata_msense_control_spg0(dev, buf, changeable);
n += ata_msense_control_spgt2(dev, buf + n, CDL_T2A_SUB_MPAGE);
n += ata_msense_control_spgt2(dev, buf + n, CDL_T2A_SUB_MPAGE);
+ n += ata_msense_control_ata_feature(dev, buf + n);
return n;
default:
return 0;
@@ -2391,7 +2421,7 @@ static unsigned int ata_scsiop_mode_sense(struct ata_scsi_args *args, u8 *rbuf)
spg = scsicmd[3];

/*
- * Supported subpages: all subpages and sub-pages 07h and 08h of
+ * Supported subpages: all subpages and sub-pages 07h, 08h and f2h of
* the control page.
*/
if (spg) {
@@ -2400,6 +2430,7 @@ static unsigned int ata_scsiop_mode_sense(struct ata_scsi_args *args, u8 *rbuf)
break;
case CDL_T2A_SUB_MPAGE:
case CDL_T2B_SUB_MPAGE:
+ case ATA_FEATURE_SUB_MPAGE:
if (dev->flags & ATA_DFLAG_CDL && pg == CONTROL_MPAGE)
break;
fallthrough;
@@ -3708,20 +3739,11 @@ static int ata_mselect_caching(struct ata_queued_cmd *qc,
return 0;
}

-/**
- * ata_mselect_control - Simulate MODE SELECT for control page
- * @qc: Storage for translated ATA taskfile
- * @buf: input buffer
- * @len: number of valid bytes in the input buffer
- * @fp: out parameter for the failed field on error
- *
- * Prepare a taskfile to modify caching information for the device.
- *
- * LOCKING:
- * None.
+/*
+ * Simulate MODE SELECT control mode page, sub-page 0.
*/
-static int ata_mselect_control(struct ata_queued_cmd *qc,
- const u8 *buf, int len, u16 *fp)
+static int ata_mselect_control_spg0(struct ata_queued_cmd *qc,
+ const u8 *buf, int len, u16 *fp)
{
struct ata_device *dev = qc->dev;
u8 mpage[CONTROL_MPAGE_LEN];
@@ -3759,6 +3781,83 @@ static int ata_mselect_control(struct ata_queued_cmd *qc,
return 0;
}

+/*
+ * Translate MODE SELECT control mode page, sub-pages f2h (ATA feature mode
+ * page) into a SET FEATURES command.
+ */
+static unsigned int ata_mselect_control_ata_feature(struct ata_queued_cmd *qc,
+ const u8 *buf, int len,
+ u16 *fp)
+{
+ struct ata_device *dev = qc->dev;
+ struct ata_taskfile *tf = &qc->tf;
+ u8 cdl_action;
+
+ /*
+ * The first four bytes of ATA Feature Control mode page are a header,
+ * so offsets in mpage are off by 4 compared to buf. Same for len.
+ */
+ if (len != ATA_FEATURE_SUB_MPAGE_LEN - 4) {
+ *fp = min(len, ATA_FEATURE_SUB_MPAGE_LEN - 4);
+ return -EINVAL;
+ }
+
+ /* Check cdl_ctrl */
+ switch (buf[0] & 0x03) {
+ case 0:
+ /* Disable CDL */
+ cdl_action = 0;
+ dev->flags &= ~ATA_DFLAG_CDL_ENABLED;
+ break;
+ case 0x02:
+ /* Enable CDL T2A/T2B: NCQ priority must be disabled */
+ if (dev->flags & ATA_DFLAG_NCQ_PRIO_ENABLED) {
+ ata_dev_err(dev,
+ "NCQ priority must be disabled to enable CDL\n");
+ return -EINVAL;
+ }
+ cdl_action = 1;
+ dev->flags |= ATA_DFLAG_CDL_ENABLED;
+ break;
+ default:
+ *fp = 0;
+ return -EINVAL;
+ }
+
+ tf->flags |= ATA_TFLAG_DEVICE | ATA_TFLAG_ISADDR;
+ tf->protocol = ATA_PROT_NODATA;
+ tf->command = ATA_CMD_SET_FEATURES;
+ tf->feature = SETFEATURES_CDL;
+ tf->nsect = cdl_action;
+
+ return 1;
+}
+
+/**
+ * ata_mselect_control - Simulate MODE SELECT for control page
+ * @qc: Storage for translated ATA taskfile
+ * @buf: input buffer
+ * @len: number of valid bytes in the input buffer
+ * @fp: out parameter for the failed field on error
+ *
+ * Prepare a taskfile to modify caching information for the device.
+ *
+ * LOCKING:
+ * None.
+ */
+static int ata_mselect_control(struct ata_queued_cmd *qc, u8 spg,
+ const u8 *buf, int len, u16 *fp)
+{
+ switch (spg) {
+ case 0:
+ return ata_mselect_control_spg0(qc, buf, len, fp);
+ case ATA_FEATURE_SUB_MPAGE:
+ return ata_mselect_control_ata_feature(qc, buf, len, fp);
+ default:
+ return -EINVAL;
+ }
+}
+
/**
* ata_scsi_mode_select_xlat - Simulate MODE SELECT 6, 10 commands
* @qc: Storage for translated ATA taskfile
@@ -3776,7 +3875,7 @@ static unsigned int ata_scsi_mode_select_xlat(struct ata_queued_cmd *qc)
const u8 *cdb = scmd->cmnd;
u8 pg, spg;
unsigned six_byte, pg_len, hdr_len, bd_len;
- int len;
+ int len, ret;
u16 fp = (u16)-1;
u8 bp = 0xff;
u8 buffer[64];
@@ -3861,13 +3960,29 @@ static unsigned int ata_scsi_mode_select_xlat(struct ata_queued_cmd *qc)
}

/*
- * No mode subpages supported (yet) but asking for _all_
- * subpages may be valid
+ * Supported subpages: all subpages and ATA feature sub-page f2h of
+ * the control page.
*/
- if (spg && (spg != ALL_SUB_MPAGES)) {
- fp = (p[0] & 0x40) ? 1 : 0;
- fp += hdr_len + bd_len;
- goto invalid_param;
+ if (spg) {
+ switch (spg) {
+ case ALL_SUB_MPAGES:
+ /* All subpages is not supported for the control page */
+ if (pg == CONTROL_MPAGE) {
+ fp = (p[0] & 0x40) ? 1 : 0;
+ fp += hdr_len + bd_len;
+ goto invalid_param;
+ }
+ break;
+ case ATA_FEATURE_SUB_MPAGE:
+ if (qc->dev->flags & ATA_DFLAG_CDL &&
+ pg == CONTROL_MPAGE)
+ break;
+ fallthrough;
+ default:
+ fp = (p[0] & 0x40) ? 1 : 0;
+ fp += hdr_len + bd_len;
+ goto invalid_param;
+ }
}
if (pg_len > len)
goto invalid_param_len;
@@ -3880,14 +3995,16 @@ static unsigned int ata_scsi_mode_select_xlat(struct ata_queued_cmd *qc)
}
break;
case CONTROL_MPAGE:
- if (ata_mselect_control(qc, p, pg_len, &fp) < 0) {
+ ret = ata_mselect_control(qc, spg, p, pg_len, &fp);
+ if (ret < 0) {
fp += hdr_len + bd_len;
goto invalid_param;
- } else {
- goto skip; /* No ATA command to send */
}
+ if (!ret)
+ goto skip; /* No ATA command to send */
break;
- default: /* invalid page code */
+ default:
+ /* Invalid page code */
fp = bd_len + hdr_len;
goto invalid_param;
}
diff --git a/include/linux/ata.h b/include/linux/ata.h
index b01e2cebe1fe..a59b17d6ad11 100644
--- a/include/linux/ata.h
+++ b/include/linux/ata.h
@@ -330,6 +330,7 @@ enum {

/* Identify device log pages: */
ATA_LOG_SUPPORTED_CAPABILITIES = 0x03,
+ ATA_LOG_CURRENT_SETTINGS = 0x04,
ATA_LOG_SECURITY = 0x06,
ATA_LOG_SATA_SETTINGS = 0x08,
ATA_LOG_ZONED_INFORMATION = 0x09,
@@ -419,6 +420,8 @@ enum {
SETFEATURES_SATA_ENABLE = 0x10, /* Enable use of SATA feature */
SETFEATURES_SATA_DISABLE = 0x90, /* Disable use of SATA feature */

+ SETFEATURES_CDL = 0x0d, /* Enable/disable cmd duration limits */
+
/* SETFEATURE Sector counts for SATA features */
SATA_FPDMA_OFFSET = 0x01, /* FPDMA non-zero buffer offsets */
SATA_FPDMA_AA = 0x02, /* FPDMA Setup FIS Auto-Activate */
diff --git a/include/linux/libata.h b/include/linux/libata.h
index 2b17d6c99a37..d7fe735e6322 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -106,6 +106,7 @@ enum {
ATA_DFLAG_INIT_MASK = (1 << 20) - 1,

ATA_DFLAG_NCQ_PRIO_ENABLED = (1 << 20), /* Priority cmds sent to dev */
+ ATA_DFLAG_CDL_ENABLED = (1 << 21), /* cmd duration limits is enabled */
ATA_DFLAG_DETACH = (1 << 24),
ATA_DFLAG_DETACHED = (1 << 25),
ATA_DFLAG_DA = (1 << 26), /* device supports Device Attention */
--
2.39.2