Thread (1 message) flat view 1 message, 1 author, 2021-12-23

Re: [PATCH v3] virtio_blk: Add support for lifetime feature

From: Greg KH <gregkh@linuxfoundation.org>
Date: 2021-12-23 10:47:59
Also in: linux-block, lkml

[note, your original post had the to: line messed up, which caused any
response to this to not work well in many email clients, this is a
resend...]

On Tue, Dec 07, 2021 at 10:55:17AM -0700, Enrico Granata wrote:
From: Enrico Granata <redacted>

The VirtIO TC has adopted a new feature in virtio-blk enabling
discovery of lifetime information.

This commit adds support for the VIRTIO_BLK_T_LIFETIME command
to the virtio_blk driver, and adds new attributes to the
sysfs entry for virtio_blk:
* pre_eol_info
* life_time_a
* life_time_b

which are defined in the VirtIO specification.

Signed-off-by: Enrico Granata <redacted>
---
Changes in v3:
 - Split life_time attribute in two
 - Made VirtIO specification independent of eMMC
 - Adopted newer APIs to mirror surrounding code

 drivers/block/virtio_blk.c      | 106 ++++++++++++++++++++++++++++++--
 include/uapi/linux/virtio_blk.h |  11 ++++
 2 files changed, 113 insertions(+), 4 deletions(-)
You seem to be missing new Documentation/ABI/ entries for these new
sysfs files you are adding.  That is required.
quoted hunk
diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c
index 6ae38776e30e..c50f5d9a173b 100644
--- a/drivers/block/virtio_blk.c
+++ b/drivers/block/virtio_blk.c
@@ -213,7 +213,7 @@ static blk_status_t virtblk_setup_cmd(struct virtio_device *vdev,
 				      struct virtblk_req *vbr)
 {
 	bool unmap = false;
-	u32 type;
+	u32 type = 0;
VIRTIO_BLK_T_GET_ID?

And why isn't this an enum?
quoted hunk
 
 	vbr->out_hdr.sector = 0;
 
@@ -239,14 +239,14 @@ static blk_status_t virtblk_setup_cmd(struct virtio_device *vdev,
 		unmap = !(req->cmd_flags & REQ_NOUNMAP);
 		break;
 	case REQ_OP_DRV_IN:
-		type = VIRTIO_BLK_T_GET_ID;
-		break;
+		break; /* type already set for custom requests */
 	default:
 		WARN_ON_ONCE(1);
 		return BLK_STS_IOERR;
 	}
 
-	vbr->out_hdr.type = cpu_to_virtio32(vdev, type);
+	if (req_op(req) != REQ_OP_DRV_IN)
+		vbr->out_hdr.type = cpu_to_virtio32(vdev, type);
 	vbr->out_hdr.ioprio = cpu_to_virtio32(vdev, req_get_ioprio(req));
 
 	if (type == VIRTIO_BLK_T_DISCARD || type == VIRTIO_BLK_T_WRITE_ZEROES) {
@@ -374,11 +374,14 @@ static int virtblk_get_id(struct gendisk *disk, char *id_str)
 	struct virtio_blk *vblk = disk->private_data;
 	struct request_queue *q = vblk->disk->queue;
 	struct request *req;
+	struct virtblk_req *vbr;
 	int err;
 
 	req = blk_mq_alloc_request(q, REQ_OP_DRV_IN, 0);
 	if (IS_ERR(req))
 		return PTR_ERR(req);
+	vbr = blk_mq_rq_to_pdu(req);
+	vbr->out_hdr.type = cpu_to_virtio32(vblk->vdev, VIRTIO_BLK_T_GET_ID);
 
 	err = blk_rq_map_kern(q, req, id_str, VIRTIO_BLK_ID_BYTES, GFP_KERNEL);
 	if (err)
@@ -391,6 +394,35 @@ static int virtblk_get_id(struct gendisk *disk, char *id_str)
 	return err;
 }
 
+static int virtblk_get_lifetime(struct gendisk *disk, struct virtio_blk_lifetime *lifetime)
+{
+	struct virtio_blk *vblk = disk->private_data;
+	struct request_queue *q = vblk->disk->queue;
+	struct request *req;
+	struct virtblk_req *vbr;
+	int err;
+
+	if (!virtio_has_feature(vblk->vdev, VIRTIO_BLK_F_LIFETIME))
+		return -EOPNOTSUPP;
+
+	req = blk_mq_alloc_request(q, REQ_OP_DRV_IN, 0);
+	if (IS_ERR(req))
+		return PTR_ERR(req);
+	vbr = blk_mq_rq_to_pdu(req);
+	vbr->out_hdr.type = cpu_to_virtio32(vblk->vdev, VIRTIO_BLK_T_GET_LIFETIME);
+
+	err = blk_rq_map_kern(q, req, lifetime, sizeof(*lifetime), GFP_KERNEL);
+	if (err)
+		goto out;
+
+	blk_execute_rq(vblk->disk, req, false);
+	err = blk_status_to_errno(virtblk_result(blk_mq_rq_to_pdu(req)));
+out:
+	blk_mq_free_request(req);
+	return err;
+}
+
+
 static void virtblk_get(struct virtio_blk *vblk)
 {
 	refcount_inc(&vblk->refs);
@@ -499,6 +531,68 @@ static ssize_t serial_show(struct device *dev,
 
 static DEVICE_ATTR_RO(serial);
 
+static ssize_t pre_eol_info_show(struct device *dev,
+								 struct device_attribute *attr,
+								 char *buf)
Please fix your editor to properly set the tab spacing for kernel
changes (hint 8).
+{
+	struct gendisk *disk = dev_to_disk(dev);
+	struct virtio_blk_lifetime lft;
+	int err;
+
+	/* sysfs gives us a PAGE_SIZE buffer */
+	BUILD_BUG_ON(sizeof(lft) >= PAGE_SIZE);
That's crazy, and wrong here, please remove.  It has nothing to do with
this function operating properly or not.
+
+	err = virtblk_get_lifetime(disk, &lft);
+	if (err)
+		return 0;
Please return the error.
+
+	return sprintf(buf, "0x%02x\n", le16_to_cpu(lft.pre_eol_info));
sysfs_emit() for all new sysfs show functions.
+}
Why are you mixing sysfs files with a new uapi function in the same
patch?  Shouldn't this be at least 2 patches as part of a series?

thanks,

greg k-h
_______________________________________________
Virtualization mailing list
Virtualization@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/virtualization
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help