block: Add a disk flag to block integrity profile
So far we have relied on the app tag size to determine whether a disk
has been formatted with T10 protection information or not. However, not
all target devices provide application tag storage.
Add a flag to the block integrity profile that indicates whether the
disk has been formatted with protection information.
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Sagi Grimberg <sagig@dev.mellanox.co.il>
Signed-off-by: Jens Axboe <axboe@fb.com>
diff --git a/Documentation/ABI/testing/sysfs-block b/Documentation/ABI/testing/sysfs-block
index 279da08..8df0039 100644
--- a/Documentation/ABI/testing/sysfs-block
+++ b/Documentation/ABI/testing/sysfs-block
@@ -53,6 +53,14 @@
512 bytes of data.
+What: /sys/block/<disk>/integrity/device_is_integrity_capable
+Date: July 2014
+Contact: Martin K. Petersen <martin.petersen@oracle.com>
+Description:
+ Indicates whether a storage device is capable of storing
+ integrity metadata. Set if the device is T10 PI-capable.
+
+
What: /sys/block/<disk>/integrity/write_generate
Date: June 2008
Contact: Martin K. Petersen <martin.petersen@oracle.com>
diff --git a/block/blk-integrity.c b/block/blk-integrity.c
index a7436cc..1c6ba44 100644
--- a/block/blk-integrity.c
+++ b/block/blk-integrity.c
@@ -307,6 +307,12 @@
return sprintf(page, "%d\n", (bi->flags & BLK_INTEGRITY_GENERATE) != 0);
}
+static ssize_t integrity_device_show(struct blk_integrity *bi, char *page)
+{
+ return sprintf(page, "%u\n",
+ (bi->flags & BLK_INTEGRITY_DEVICE_CAPABLE) != 0);
+}
+
static struct integrity_sysfs_entry integrity_format_entry = {
.attr = { .name = "format", .mode = S_IRUGO },
.show = integrity_format_show,
@@ -329,11 +335,17 @@
.store = integrity_generate_store,
};
+static struct integrity_sysfs_entry integrity_device_entry = {
+ .attr = { .name = "device_is_integrity_capable", .mode = S_IRUGO },
+ .show = integrity_device_show,
+};
+
static struct attribute *integrity_attrs[] = {
&integrity_format_entry.attr,
&integrity_tag_size_entry.attr,
&integrity_verify_entry.attr,
&integrity_generate_entry.attr,
+ &integrity_device_entry.attr,
NULL,
};
diff --git a/drivers/scsi/sd_dif.c b/drivers/scsi/sd_dif.c
index 801c418..1e971c6 100644
--- a/drivers/scsi/sd_dif.c
+++ b/drivers/scsi/sd_dif.c
@@ -270,7 +270,13 @@
"Enabling DIX %s protection\n", disk->integrity->name);
/* Signal to block layer that we support sector tagging */
- if (dif && type && sdkp->ATO) {
+ if (dif && type) {
+
+ disk->integrity->flags |= BLK_INTEGRITY_DEVICE_CAPABLE;
+
+ if (!sdkp)
+ return;
+
if (type == SD_DIF_TYPE3_PROTECTION)
disk->integrity->tag_size = sizeof(u16) + sizeof(u32);
else
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index cf92eb0..4600fc6 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -1461,6 +1461,7 @@
enum blk_integrity_flags {
BLK_INTEGRITY_VERIFY = 1 << 0,
BLK_INTEGRITY_GENERATE = 1 << 1,
+ BLK_INTEGRITY_DEVICE_CAPABLE = 1 << 2,
};
struct blk_integrity_iter {