[PATCH v2 09/20] nvme: Add helper to execute Reservation Report

[Mike Christie]

This adds a helper to execute the Reservation Report. The next patches
will then convert call it and convert that info to read_keys and
read_reservation.

Signed-off-by: Mike Christie <michael.christie at oracle.com>
---
 drivers/nvme/host/core.c | 27 +++++++++++++++++++++++++++
 1 file changed, 27 insertions(+)

diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
index 0dc768ae0c16..6b22a5dec122 100644
--- a/drivers/nvme/host/core.c
+++ b/drivers/nvme/host/core.c
@@ -2196,6 +2196,33 @@ 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, u8 *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 = 1;
+	*eds = true;
+
+retry:
+	if (IS_ENABLED(CONFIG_NVME_MULTIPATH) &&
+	    bdev->bd_disk->fops == &nvme_ns_head_ops)
+		ret = nvme_send_ns_head_pr_command(bdev, &c, data, data_len);
+	else
+		ret = nvme_send_ns_pr_command(bdev->bd_disk->private_data, &c,
+					      data, data_len);
+	if (ret == NVME_SC_HOST_ID_INCONSIST && c.common.cdw11) {
+		c.common.cdw11 = 0;
+		*eds = false;
+		goto retry;
+	}
+
+	return ret;
+}
+
 const struct pr_ops nvme_pr_ops = {
 	.pr_register	= nvme_pr_register,
 	.pr_reserve	= nvme_pr_reserve,
-- 
2.18.2