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 <[email protected]> Cc: Kay Sievers <[email protected]> Cc: Doug Gilbert <[email protected]> Cc: Kai Makisara <[email protected]> Signed-off-by: Hannes Reinecke <[email protected]> --- 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 -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
