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 | 31 ++++++++++++++++++++++-
include/scsi/scsi_device.h | 3 +++
4 files changed, 98 insertions(+), 1 deletion(-)
diff --git a/drivers/scsi/scsi.c b/drivers/scsi/scsi.c
index 9e08d3d..0aa1925 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..a11bead 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);
@@ -754,8 +755,31 @@ store_queue_type_field(struct device *dev, struct device_attribute *attr,
static DEVICE_ATTR(queue_type, S_IRUGO | S_IWUSR, show_queue_type_field,
store_queue_type_field);
+#define sdev_vpd_pg_attr(_page) \
+static ssize_t \
+show_vpd_##_page(struct file *filp, struct kobject *kobj, \
+ struct bin_attribute *bin_attr, \
+ char *buf, loff_t off, size_t count) \
+{ \
+ struct device *dev = container_of(kobj, struct device, kobj); \
+ struct scsi_device *sdev = to_scsi_device(dev); \
+ if (!sdev->vpd_##_page) \
+ return -EINVAL; \
+ return memory_read_from_buffer(buf, count, &off, \
+ sdev->vpd_##_page, \
+ sdev->vpd_##_page##_len); \
+} \
+static struct bin_attribute dev_attr_vpd_##_page = { \
+ .attr = {.name = __stringify(vpd_##_page), .mode = S_IRUGO }, \
+ .size = 0, \
+ .read = show_vpd_##_page, \
+};
+
+sdev_vpd_pg_attr(pg83);
+
static ssize_t
-show_iostat_counterbits(struct device *dev, struct device_attribute *attr, char *buf)
+show_iostat_counterbits(struct device *dev, struct device_attribute *attr,
+ char *buf)
{
return snprintf(buf, 20, "%d\n", (int)sizeof(atomic_t) * 8);
}
@@ -939,8 +963,13 @@ static struct attribute *scsi_sdev_attrs[] = {
NULL
};
+static struct bin_attribute *scsi_sdev_bin_attrs[] = {
+ &dev_attr_vpd_pg83,
+ NULL
+};
static struct attribute_group scsi_sdev_attr_group = {
.attrs = scsi_sdev_attrs,
+ .bin_attrs = scsi_sdev_bin_attrs,
.is_visible = scsi_sdev_attr_is_visible,
};
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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