This patch implements a VPD page rescan if the 'rescan' sysfs
attribute is triggered.
Signed-off-by: Hannes Reinecke <hare@xxxxxxx>
---
drivers/scsi/device_handler/scsi_dh_alua.c | 11 +++++++----
drivers/scsi/scsi.c | 20 +++++++++++++++++---
drivers/scsi/scsi_scan.c | 4 ++++
drivers/scsi/scsi_sysfs.c | 8 ++++++--
drivers/scsi/ses.c | 6 ++++--
include/scsi/scsi_device.h | 1 +
6 files changed, 39 insertions(+), 11 deletions(-)
diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c
index d077014..e4cabc8 100644
--- a/drivers/scsi/device_handler/scsi_dh_alua.c
+++ b/drivers/scsi/device_handler/scsi_dh_alua.c
@@ -264,8 +264,11 @@ static int alua_check_vpd(struct scsi_device *sdev, struct alua_dh_data *h)
int device_id_size, device_id_type = 0;
struct alua_port_group *tmp_pg, *pg = NULL;
- if (!sdev->vpd_pg83)
+ rcu_read_lock();
+ if (!rcu_dereference(sdev->vpd_pg83)) {
+ rcu_read_unlock();
return SCSI_DH_DEV_UNSUPP;
+ }
/*
* Look for the correct descriptor.
@@ -281,8 +284,8 @@ static int alua_check_vpd(struct scsi_device *sdev, struct alua_dh_data *h)
*/
memset(device_id_str, 0, 256);
device_id_size = 0;
- d = sdev->vpd_pg83 + 4;
- while (d < sdev->vpd_pg83 + sdev->vpd_pg83_len) {
+ d = rcu_dereference(sdev->vpd_pg83) + 4;
+ while (d < rcu_dereference(sdev->vpd_pg83) + sdev->vpd_pg83_len) {
switch (d[1] & 0xf) {
case 0x2:
/* EUI-64 */
@@ -366,7 +369,7 @@ static int alua_check_vpd(struct scsi_device *sdev, struct alua_dh_data *h)
}
d += d[3] + 4;
}
-
+ rcu_read_unlock();
if (group_id == -1) {
/*
* Internal error; TPGS supported but required
diff --git a/drivers/scsi/scsi.c b/drivers/scsi/scsi.c
index 207d6a7..f1c0fb5 100644
--- a/drivers/scsi/scsi.c
+++ b/drivers/scsi/scsi.c
@@ -803,7 +803,7 @@ void scsi_attach_vpd(struct scsi_device *sdev)
int vpd_len = SCSI_VPD_PG_LEN;
int pg80_supported = 0;
int pg83_supported = 0;
- unsigned char *vpd_buf;
+ unsigned char *vpd_buf, *orig_vpd_buf = NULL;
if (sdev->skip_vpd_pages)
return;
@@ -849,8 +849,16 @@ retry_pg80:
kfree(vpd_buf);
goto retry_pg80;
}
+ mutex_lock(&sdev->inquiry_mutex);
+ orig_vpd_buf = sdev->vpd_pg80;
sdev->vpd_pg80_len = result;
- sdev->vpd_pg80 = vpd_buf;
+ rcu_assign_pointer(sdev->vpd_pg80, vpd_buf);
+ mutex_unlock(&sdev->inquiry_mutex);
+ synchronize_rcu();
+ if (orig_vpd_buf) {
+ kfree(orig_vpd_buf);
+ orig_vpd_buf = NULL;
+ }
vpd_len = SCSI_VPD_PG_LEN;
}
@@ -870,8 +878,14 @@ retry_pg83:
kfree(vpd_buf);
goto retry_pg83;
}
+ mutex_lock(&sdev->inquiry_mutex);
+ orig_vpd_buf = sdev->vpd_pg83;
sdev->vpd_pg83_len = result;
- sdev->vpd_pg83 = vpd_buf;
+ rcu_assign_pointer(sdev->vpd_pg83, vpd_buf);
+ mutex_unlock(&sdev->inquiry_mutex);
+ synchronize_rcu();
+ if (orig_vpd_buf)
+ kfree(orig_vpd_buf);
}
}
diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c
index f9f3f82..190d743 100644
--- a/drivers/scsi/scsi_scan.c
+++ b/drivers/scsi/scsi_scan.c
@@ -235,6 +235,7 @@ static struct scsi_device *scsi_alloc_sdev(struct scsi_target *starget,
INIT_LIST_HEAD(&sdev->starved_entry);
INIT_LIST_HEAD(&sdev->event_list);
spin_lock_init(&sdev->list_lock);
+ mutex_init(&sdev->inquiry_mutex);
INIT_WORK(&sdev->event_work, scsi_evt_thread);
INIT_WORK(&sdev->requeue_work, scsi_requeue_run_queue);
@@ -1516,6 +1517,9 @@ EXPORT_SYMBOL(scsi_add_device);
void scsi_rescan_device(struct device *dev)
{
device_lock(dev);
+
+ scsi_attach_vpd(to_scsi_device(dev));
+
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 e3c3b86..b4de776 100644
--- a/drivers/scsi/scsi_sysfs.c
+++ b/drivers/scsi/scsi_sysfs.c
@@ -759,11 +759,15 @@ show_vpd_##_page(struct file *filp, struct kobject *kobj, \
{ \
struct device *dev = container_of(kobj, struct device, kobj); \
struct scsi_device *sdev = to_scsi_device(dev); \
+ int ret; \
if (!sdev->vpd_##_page) \
return -EINVAL; \
- return memory_read_from_buffer(buf, count, &off, \
- sdev->vpd_##_page, \
+ rcu_read_lock(); \
+ ret = memory_read_from_buffer(buf, count, &off, \
+ rcu_dereference(sdev->vpd_##_page), \
sdev->vpd_##_page##_len); \
+ rcu_read_unlock(); \
+ return ret; \
} \
static struct bin_attribute dev_attr_vpd_##_page = { \
.attr = {.name = __stringify(vpd_##_page), .mode = S_IRUGO }, \
diff --git a/drivers/scsi/ses.c b/drivers/scsi/ses.c
index dcb0d76..1fc372e 100644
--- a/drivers/scsi/ses.c
+++ b/drivers/scsi/ses.c
@@ -563,8 +563,9 @@ static void ses_match_to_enclosure(struct enclosure_device *edev,
if (!sdev->vpd_pg83_len)
return;
- desc = sdev->vpd_pg83 + 4;
- while (desc < sdev->vpd_pg83 + sdev->vpd_pg83_len) {
+ rcu_read_lock();
+ desc = rcu_dereference(sdev->vpd_pg83) + 4;
+ while (desc < rcu_dereference(sdev->vpd_pg83) + sdev->vpd_pg83_len) {
enum scsi_protocol proto = desc[0] >> 4;
u8 code_set = desc[0] & 0x0f;
u8 piv = desc[1] & 0x80;
@@ -578,6 +579,7 @@ static void ses_match_to_enclosure(struct enclosure_device *edev,
desc += len + 4;
}
+ rcu_read_unlock();
if (efd.addr) {
efd.dev = &sdev->sdev_gendev;
diff --git a/include/scsi/scsi_device.h b/include/scsi/scsi_device.h
index 2725f8f..d2f8b7a 100644
--- a/include/scsi/scsi_device.h
+++ b/include/scsi/scsi_device.h
@@ -109,6 +109,7 @@ struct scsi_device {
char type;
char scsi_level;
char inq_periph_qual; /* PQ from INQUIRY data */
+ struct mutex inquiry_mutex;
unsigned char inquiry_len; /* valid bytes in 'inquiry' */
unsigned char * inquiry; /* INQUIRY response data */
const char * vendor; /* [back_compat] point into 'inquiry' ... */
--
1.8.5.2
--
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