For when no device handler is used, add ALUA support.
This will be equivalent to when native SCSI multipathing is used.
Essentially all the same handling is available as DH alua driver for
rescan, request prep, sense handling.
Signed-off-by: John Garry <[email protected]>
---
drivers/scsi/scsi_alua.c | 93 +++++++++++++++++++++++++++++++++++++++
drivers/scsi/scsi_error.c | 7 +++
drivers/scsi/scsi_lib.c | 7 +++
drivers/scsi/scsi_scan.c | 2 +
drivers/scsi/scsi_sysfs.c | 4 +-
include/scsi/scsi_alua.h | 14 ++++++
6 files changed, 126 insertions(+), 1 deletion(-)
diff --git a/drivers/scsi/scsi_alua.c b/drivers/scsi/scsi_alua.c
index d3fcd887e5018..ee0229b1a9d12 100644
--- a/drivers/scsi/scsi_alua.c
+++ b/drivers/scsi/scsi_alua.c
@@ -562,6 +562,90 @@ int scsi_alua_stpg_run(struct scsi_device *sdev, bool
optimize)
}
EXPORT_SYMBOL_GPL(scsi_alua_stpg_run);
+enum scsi_disposition scsi_alua_check_sense(struct scsi_device *sdev,
+ struct scsi_sense_hdr *sense_hdr)
+{
+ switch (sense_hdr->sense_key) {
+ case NOT_READY:
+ if (sense_hdr->asc == 0x04 && sense_hdr->ascq == 0x0a) {
+ /*
+ * LUN Not Accessible - ALUA state transition
+ */
+ scsi_alua_handle_state_transition(sdev);
+ return NEEDS_RETRY;
+ }
+ break;
+ case UNIT_ATTENTION:
+ if (sense_hdr->asc == 0x04 && sense_hdr->ascq == 0x0a) {
+ /*
+ * LUN Not Accessible - ALUA state transition
+ */
+ scsi_alua_handle_state_transition(sdev);
+ return NEEDS_RETRY;
+ }
+ if (sense_hdr->asc == 0x29 && sense_hdr->ascq == 0x00) {
+ /*
+ * Power On, Reset, or Bus Device Reset.
+ * Might have obscured a state transition,
+ * so schedule a recheck.
+ */
+ scsi_device_alua_rescan(sdev);
+ return ADD_TO_MLQUEUE;
+ }
+ if (sense_hdr->asc == 0x29 && sense_hdr->ascq == 0x04)
+ /*
+ * Device internal reset
+ */
+ return ADD_TO_MLQUEUE;
+ if (sense_hdr->asc == 0x2a && sense_hdr->ascq == 0x01)
+ /*
+ * Mode Parameters Changed
+ */
+ return ADD_TO_MLQUEUE;
+ if (sense_hdr->asc == 0x2a && sense_hdr->ascq == 0x06) {
+ /*
+ * ALUA state changed
+ */
+ scsi_device_alua_rescan(sdev);
+ return ADD_TO_MLQUEUE;
+ }
+ if (sense_hdr->asc == 0x2a && sense_hdr->ascq == 0x07) {
+ /*
+ * Implicit ALUA state transition failed
+ */
+ scsi_device_alua_rescan(sdev);
+ return ADD_TO_MLQUEUE;
+ }
+ if (sense_hdr->asc == 0x3f && sense_hdr->ascq == 0x03)
+ /*
+ * Inquiry data has changed
+ */
+ return ADD_TO_MLQUEUE;
+ if (sense_hdr->asc == 0x3f && sense_hdr->ascq == 0x0e)
+ /*
+ * REPORTED_LUNS_DATA_HAS_CHANGED is reported
+ * when switching controllers on targets like
+ * Intel Multi-Flex. We can just retry.
+ */
+ return ADD_TO_MLQUEUE;
+ break;
+ }
+
+ return SCSI_RETURN_NOT_HANDLED;
+}
+
+static void alua_rtpg_work(struct work_struct *work)
+{
+ struct alua_data *alua =
+ container_of(work, struct alua_data, work.work);
+ int ret;
+
+ ret = scsi_alua_rtpg_run(alua->sdev);
+
+ if (ret == -EAGAIN)
+ queue_delayed_work(kalua_wq, &alua->work, alua->interval * HZ);
+}
+
int scsi_alua_sdev_init(struct scsi_device *sdev)
{
int rel_port, ret, tpgs;
@@ -591,6 +675,7 @@ int scsi_alua_sdev_init(struct scsi_device *sdev)
goto out_free_data;
}
+ INIT_DELAYED_WORK(&sdev->alua->work, alua_rtpg_work);
sdev->alua->sdev = sdev;
sdev->alua->tpgs = tpgs;
spin_lock_init(&sdev->alua->lock);
@@ -638,6 +723,14 @@ bool scsi_device_alua_implicit(struct scsi_device *sdev)
return sdev->alua->tpgs & TPGS_MODE_IMPLICIT;
}
+void scsi_device_alua_rescan(struct scsi_device *sdev)
+{
+ struct alua_data *alua = sdev->alua;
+
+ queue_delayed_work(kalua_wq, &alua->work,
+ msecs_to_jiffies(ALUA_RTPG_DELAY_MSECS));
+}
+
int scsi_alua_init(void)
{
kalua_wq = alloc_workqueue("kalua", WQ_MEM_RECLAIM | WQ_PERCPU, 0);
diff --git a/drivers/scsi/scsi_error.c b/drivers/scsi/scsi_error.c
index 147127fb4db9c..a542e7a85a24d 100644
--- a/drivers/scsi/scsi_error.c
+++ b/drivers/scsi/scsi_error.c
@@ -29,6 +29,7 @@
#include <linux/jiffies.h>
#include <scsi/scsi.h>
+#include <scsi/scsi_alua.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_dbg.h>
#include <scsi/scsi_device.h>
@@ -578,6 +579,12 @@ enum scsi_disposition scsi_check_sense(struct scsi_cmnd
*scmd)
if (rc != SCSI_RETURN_NOT_HANDLED)
return rc;
/* handler does not care. Drop down to default handling */
+ } else if (scsi_device_alua_implicit(sdev)) {
+ enum scsi_disposition rc;
+
+ rc = scsi_alua_check_sense(sdev, &sshdr);
+ if (rc != SCSI_RETURN_NOT_HANDLED)
+ return rc;
}
if (scmd->cmnd[0] == TEST_UNIT_READY &&
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index d3a8cd4166f92..e5bcee555ea10 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -26,6 +26,7 @@
#include <linux/unaligned.h>
#include <scsi/scsi.h>
+#include <scsi/scsi_alua.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_dbg.h>
#include <scsi/scsi_device.h>
@@ -1719,6 +1720,12 @@ static blk_status_t scsi_prepare_cmd(struct request *req)
if (sdev->handler && sdev->handler->prep_fn) {
blk_status_t ret = sdev->handler->prep_fn(sdev, req);
+ if (ret != BLK_STS_OK)
+ return ret;
+ } else if (scsi_device_alua_implicit(sdev)) {
+ /* We should be able to make this common for ALUA DH as well */
+ blk_status_t ret = scsi_alua_prep_fn(sdev, req);
+
if (ret != BLK_STS_OK)
return ret;
}
diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c
index 3af64d1231445..73caf83bd1097 100644
--- a/drivers/scsi/scsi_scan.c
+++ b/drivers/scsi/scsi_scan.c
@@ -1744,6 +1744,8 @@ int scsi_rescan_device(struct scsi_device *sdev)
if (sdev->handler && sdev->handler->rescan)
sdev->handler->rescan(sdev);
+ else if (scsi_device_alua_implicit(sdev))
+ scsi_device_alua_rescan(sdev);
if (dev->driver && try_module_get(dev->driver->owner)) {
struct scsi_driver *drv = to_scsi_driver(dev->driver);
diff --git a/drivers/scsi/scsi_sysfs.c b/drivers/scsi/scsi_sysfs.c
index 6c4c3c22f6acf..71a9613898cfc 100644
--- a/drivers/scsi/scsi_sysfs.c
+++ b/drivers/scsi/scsi_sysfs.c
@@ -1152,7 +1152,7 @@ sdev_show_access_state(struct device *dev,
unsigned char access_state;
const char *access_state_name;
- if (!sdev->handler)
+ if (!sdev->handler && !scsi_device_alua_implicit(sdev))
return -EINVAL;
access_state = (sdev->access_state & SCSI_ACCESS_STATE_MASK);
@@ -1409,6 +1409,8 @@ int scsi_sysfs_add_sdev(struct scsi_device *sdev)
scsi_autopm_get_device(sdev);
scsi_dh_add_device(sdev);
+ if (!sdev->handler && scsi_device_alua_implicit(sdev))
+ scsi_device_alua_rescan(sdev);
error = device_add(&sdev->sdev_gendev);
if (error) {
diff --git a/include/scsi/scsi_alua.h b/include/scsi/scsi_alua.h
index 2d5db944f75b7..8e506d1d66cce 100644
--- a/include/scsi/scsi_alua.h
+++ b/include/scsi/scsi_alua.h
@@ -24,6 +24,7 @@ struct alua_data {
unsigned char transition_tmo;
unsigned long expiry;
unsigned long interval;
+ struct delayed_work work;
struct scsi_device *sdev;
spinlock_t lock;
};
@@ -35,11 +36,15 @@ void scsi_alua_handle_state_transition(struct scsi_device
*sdev);
int scsi_alua_check_tpgs(struct scsi_device *sdev);
+enum scsi_disposition scsi_alua_check_sense(struct scsi_device *sdev,
+ struct scsi_sense_hdr *sense_hdr);
+
int scsi_alua_rtpg_run(struct scsi_device *sdev);
int scsi_alua_stpg_run(struct scsi_device *sdev, bool optimize);
blk_status_t scsi_alua_prep_fn(struct scsi_device *sdev, struct request *req);
+void scsi_device_alua_rescan(struct scsi_device *sdev);
bool scsi_device_alua_implicit(struct scsi_device *sdev);
int scsi_alua_init(void);
@@ -53,6 +58,12 @@ static inline int scsi_alua_check_tpgs(struct scsi_device
*sdev)
{
return 0;
}
+static inline
+enum scsi_disposition scsi_alua_check_sense(struct scsi_device *sdev,
+ struct scsi_sense_hdr *sense_hdr)
+{
+ return SCSI_RETURN_NOT_HANDLED;
+}
static inline int scsi_alua_rtpg_run(struct scsi_device *sdev)
{
return 0;
@@ -66,6 +77,9 @@ blk_status_t scsi_alua_prep_fn(struct scsi_device *sdev,
struct request *req)
{
return BLK_STS_OK;
}
+static inline void scsi_device_alua_rescan(struct scsi_device *sdev)
+{
+}
static inline bool scsi_device_alua_implicit(struct scsi_device *sdev)
{
return false;
