EVPD page 0x83 is used to uniquely identify the device.
So instead of having each and every program issue a separate
SG_IO call to retrieve this information it does make far more
sense to display it in sysfs.
Cc: Jeremy Linton <jlinton@xxxxxxxxxxxxx>
Cc: Kay Sievers <kay@xxxxxxxx>
Cc: Doug Gilbert <dgilbert@xxxxxxxxxxxx>
Cc: Kai Makisara <kai.makisara@xxxxxxxxxxx>
Signed-off-by: Hannes Reinecke <hare@xxxxxxx>
---
drivers/scsi/scsi.c | 62 ++++++++++++++++++++++++++++++++++++++++++++++
drivers/scsi/scsi_scan.c | 3 +++
drivers/scsi/scsi_sysfs.c | 44 +++++++++++++++++++++++++++++++-
include/scsi/scsi_device.h | 3 +++
4 files changed, 111 insertions(+), 1 deletion(-)
diff --git a/drivers/scsi/scsi.c b/drivers/scsi/scsi.c
index ecaeff1..f753373 100644
--- a/drivers/scsi/scsi.c
+++ b/drivers/scsi/scsi.c
@@ -1042,6 +1042,68 @@ int scsi_get_vpd_page(struct scsi_device *sdev, u8 page, unsigned char *buf,
EXPORT_SYMBOL_GPL(scsi_get_vpd_page);
/**
+ * scsi_attach_vpd - Attach Vital Product Data to a SCSI device structure
+ * @sdev: The device to ask
+ *
+ * Attach the 'Device Identification' VPD page (0x83) to a SCSI device
+ * structure. This information can be used to identify the device
+ * uniquely.
+ */
+void scsi_attach_vpd(struct scsi_device *sdev)
+{
+ int result, i;
+ int vpd_len = 255;
+ int pg83_supported = 0;
+ unsigned char *vpd_buf;
+
+ if (sdev->skip_vpd_pages)
+ return;
+retry_pg0:
+ vpd_buf = kmalloc(vpd_len, GFP_KERNEL);
+ if (!vpd_buf)
+ return;
+
+ /* Ask for all the pages supported by this device */
+ result = scsi_vpd_inquiry(sdev, vpd_buf, 0, vpd_len);
+ if (result < 0) {
+ kfree(vpd_buf);
+ return;
+ }
+ if (result > vpd_len) {
+ vpd_len = result;
+ kfree(vpd_buf);
+ goto retry_pg0;
+ }
+
+ for (i = 4; i < result; i++) {
+ if (vpd_buf[i] == 0x83) {
+ pg83_supported = 1;
+ }
+ }
+ kfree(vpd_buf);
+
+ if (pg83_supported) {
+retry_pg83:
+ vpd_buf = kmalloc(vpd_len, GFP_KERNEL);
+ if (!vpd_buf)
+ return;
+
+ result = scsi_vpd_inquiry(sdev, vpd_buf, 0x83, vpd_len);
+ if (result < 0) {
+ kfree(vpd_buf);
+ return;
+ }
+ if (result > vpd_len) {
+ vpd_len = result;
+ kfree(vpd_buf);
+ goto retry_pg83;
+ }
+ sdev->vpd_pg83_len = result;
+ sdev->vpd_pg83 = vpd_buf;
+ }
+}
+
+/**
* scsi_report_opcode - Find out if a given command opcode is supported
* @sdev: scsi device to query
* @buffer: scratch buffer (must be at least 20 bytes long)
diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c
index 307a811..154bb5e 100644
--- a/drivers/scsi/scsi_scan.c
+++ b/drivers/scsi/scsi_scan.c
@@ -929,6 +929,9 @@ static int scsi_add_lun(struct scsi_device *sdev, unsigned char *inq_result,
if (*bflags & BLIST_SKIP_VPD_PAGES)
sdev->skip_vpd_pages = 1;
+ if (sdev->scsi_level >= SCSI_3)
+ scsi_attach_vpd(sdev);
+
transport_configure_device(&sdev->sdev_gendev);
if (sdev->host->hostt->slave_configure) {
diff --git a/drivers/scsi/scsi_sysfs.c b/drivers/scsi/scsi_sysfs.c
index 196e59a..5d5e55a 100644
--- a/drivers/scsi/scsi_sysfs.c
+++ b/drivers/scsi/scsi_sysfs.c
@@ -415,6 +415,7 @@ static void scsi_device_dev_release_usercontext(struct work_struct *work)
scsi_target_reap(scsi_target(sdev));
+ kfree(sdev->vpd_pg83);
kfree(sdev->inquiry);
kfree(sdev);
@@ -755,7 +756,43 @@ static DEVICE_ATTR(queue_type, S_IRUGO | S_IWUSR, show_queue_type_field,
store_queue_type_field);
static ssize_t
-show_iostat_counterbits(struct device *dev, struct device_attribute *attr, char *buf)
+show_vpd_pg(const unsigned char *pg_buf, int pg_len, char *buf, int buf_len)
+{
+ int len = 0, i;
+
+ if (!pg_buf)
+ return -EINVAL;
+
+ len = 0;
+ for (i = 0; i < pg_len; i += 16) {
+ if (len + 2 > buf_len) {
+ len = -EFAULT;
+ break;
+ }
+ hex_dump_to_buffer(pg_buf + i, pg_len, 16, 1,
+ buf + len, buf_len - len, false);
+ strcat(buf + len, "\n");
+ len += strlen(buf + len);
+ }
+ return len;
+}
+
+#define sdev_vpd_pg_attr(page) \
+static ssize_t \
+show_vpd_##page(struct device *dev, struct device_attribute *attr, \
+ char *buf) \
+{ \
+ struct scsi_device *sdev = to_scsi_device(dev); \
+ return show_vpd_pg(sdev->vpd_##page, sdev->vpd_##page##_len, \
+ buf, PAGE_SIZE); \
+} \
+static DEVICE_ATTR(vpd_##page, S_IRUGO, show_vpd_##page, NULL);
+
+sdev_vpd_pg_attr(pg83);
+
+static ssize_t
+show_iostat_counterbits(struct device *dev, struct device_attribute *attr,
+ char *buf)
{
return snprintf(buf, 20, "%d\n", (int)sizeof(atomic_t) * 8);
}
@@ -905,6 +942,10 @@ static umode_t scsi_sdev_attr_is_visible(struct kobject *kobj,
!sdev->host->hostt->change_queue_type)
return S_IRUGO;
+ if (attr == &dev_attr_vpd_pg83.attr &&
+ !sdev->vpd_pg83)
+ return 0;
+
return attr->mode;
}
@@ -930,6 +971,7 @@ static struct attribute *scsi_sdev_attrs[] = {
&dev_attr_queue_depth.attr,
&dev_attr_queue_type.attr,
&dev_attr_queue_ramp_up_period.attr,
+ &dev_attr_vpd_pg83.attr,
REF_EVT(media_change),
REF_EVT(inquiry_change_reported),
REF_EVT(capacity_change_reported),
diff --git a/include/scsi/scsi_device.h b/include/scsi/scsi_device.h
index d65fbec..d209f04 100644
--- a/include/scsi/scsi_device.h
+++ b/include/scsi/scsi_device.h
@@ -113,6 +113,8 @@ struct scsi_device {
const char * vendor; /* [back_compat] point into 'inquiry' ... */
const char * model; /* ... after scan; point to static string */
const char * rev; /* ... "nullnullnullnull" before scan */
+ unsigned char vpd_pg83_len;
+ unsigned char *vpd_pg83;
unsigned char current_tag; /* current tag */
struct scsi_target *sdev_target; /* used only for single_lun */
@@ -309,6 +311,7 @@ extern int scsi_add_device(struct Scsi_Host *host, uint channel,
extern int scsi_register_device_handler(struct scsi_device_handler *scsi_dh);
extern void scsi_remove_device(struct scsi_device *);
extern int scsi_unregister_device_handler(struct scsi_device_handler *scsi_dh);
+void scsi_attach_vpd(struct scsi_device *sdev);
extern int scsi_device_get(struct scsi_device *);
extern void scsi_device_put(struct scsi_device *);
--
1.7.12.4
--
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