diff mbox series

[v6,11/18] nvme: Add pr_ops read_keys support

Message ID 20230407200551.12660-12-michael.christie@oracle.com (mailing list archive)
State Not Applicable, archived
Delegated to: Mike Snitzer
Headers show
Series Use block pr_ops in LIO | expand

Commit Message

Mike Christie April 7, 2023, 8:05 p.m. UTC
This patch adds support for the pr_ops read_keys callout by calling the
NVMe Reservation Report helper, then parsing that info to get the
controller's registered keys. Because the callout is only used in the
kernel where the callers, like LIO, do not know about controller/host IDs,
the callout just returns the registered keys which is required by the SCSI
PR in READ KEYS command.

Signed-off-by: Mike Christie <michael.christie@oracle.com>
---
 drivers/nvme/host/pr.c | 69 ++++++++++++++++++++++++++++++++++++++++++
 include/linux/nvme.h   |  4 +++
 2 files changed, 73 insertions(+)

Comments

Hannes Reinecke April 11, 2023, 7:20 a.m. UTC | #1
On 4/7/23 22:05, Mike Christie wrote:
> This patch adds support for the pr_ops read_keys callout by calling the
> NVMe Reservation Report helper, then parsing that info to get the
> controller's registered keys. Because the callout is only used in the
> kernel where the callers, like LIO, do not know about controller/host IDs,
> the callout just returns the registered keys which is required by the SCSI
> PR in READ KEYS command.
> 
> Signed-off-by: Mike Christie <michael.christie@oracle.com>
> ---
>   drivers/nvme/host/pr.c | 69 ++++++++++++++++++++++++++++++++++++++++++
>   include/linux/nvme.h   |  4 +++
>   2 files changed, 73 insertions(+)
> 
Reviewed-by: Hannes Reinecke <hare@suse.de>

Cheers,

Hannes
diff mbox series

Patch

diff --git a/drivers/nvme/host/pr.c b/drivers/nvme/host/pr.c
index cd93d2e5b340..0ee656404437 100644
--- a/drivers/nvme/host/pr.c
+++ b/drivers/nvme/host/pr.c
@@ -154,10 +154,79 @@  static int nvme_pr_release(struct block_device *bdev, u64 key, enum pr_type type
 	return nvme_pr_command(bdev, cdw10, key, 0, nvme_cmd_resv_release);
 }
 
+static int nvme_pr_resv_report(struct block_device *bdev, void *data,
+		u32 data_len, bool *eds)
+{
+	struct nvme_command c = { };
+	int ret;
+
+	c.common.opcode = nvme_cmd_resv_report;
+	c.common.cdw10 = cpu_to_le32(nvme_bytes_to_numd(data_len));
+	c.common.cdw11 = cpu_to_le32(NVME_EXTENDED_DATA_STRUCT);
+	*eds = true;
+
+retry:
+	ret = nvme_send_pr_command(bdev, &c, data, data_len);
+	if (ret == NVME_SC_HOST_ID_INCONSIST &&
+	    c.common.cdw11 == cpu_to_le32(NVME_EXTENDED_DATA_STRUCT)) {
+		c.common.cdw11 = 0;
+		*eds = false;
+		goto retry;
+	}
+
+	if (ret < 0)
+		return ret;
+
+	return nvme_sc_to_pr_err(ret);
+}
+
+static int nvme_pr_read_keys(struct block_device *bdev,
+		struct pr_keys *keys_info)
+{
+	u32 rse_len, num_keys = keys_info->num_keys;
+	struct nvme_reservation_status_ext *rse;
+	int ret, i;
+	bool eds;
+
+	/*
+	 * Assume we are using 128-bit host IDs and allocate a buffer large
+	 * enough to get enough keys to fill the return keys buffer.
+	 */
+	rse_len = struct_size(rse, regctl_eds, num_keys);
+	rse = kzalloc(rse_len, GFP_KERNEL);
+	if (!rse)
+		return -ENOMEM;
+
+	ret = nvme_pr_resv_report(bdev, rse, rse_len, &eds);
+	if (ret)
+		goto free_rse;
+
+	keys_info->generation = le32_to_cpu(rse->gen);
+	keys_info->num_keys = get_unaligned_le16(&rse->regctl);
+
+	num_keys = min(num_keys, keys_info->num_keys);
+	for (i = 0; i < num_keys; i++) {
+		if (eds) {
+			keys_info->keys[i] =
+					le64_to_cpu(rse->regctl_eds[i].rkey);
+		} else {
+			struct nvme_reservation_status *rs;
+
+			rs = (struct nvme_reservation_status *)rse;
+			keys_info->keys[i] = le64_to_cpu(rs->regctl_ds[i].rkey);
+		}
+	}
+
+free_rse:
+	kfree(rse);
+	return ret;
+}
+
 const struct pr_ops nvme_pr_ops = {
 	.pr_register	= nvme_pr_register,
 	.pr_reserve	= nvme_pr_reserve,
 	.pr_release	= nvme_pr_release,
 	.pr_preempt	= nvme_pr_preempt,
 	.pr_clear	= nvme_pr_clear,
+	.pr_read_keys	= nvme_pr_read_keys,
 };
diff --git a/include/linux/nvme.h b/include/linux/nvme.h
index 83704fc04a94..c18bd55a4ead 100644
--- a/include/linux/nvme.h
+++ b/include/linux/nvme.h
@@ -759,6 +759,10 @@  enum {
 	NVME_LBART_ATTRIB_HIDE	= 1 << 1,
 };
 
+enum nvme_eds {
+	NVME_EXTENDED_DATA_STRUCT	= 0x1,
+};
+
 struct nvme_registered_ctrl {
 	__le16	cntlid;
 	__u8	rcsts;