[PATCH 6/6] NVMe: Add persistent reservation ops

From: Christoph Hellwig
Date: Thu Oct 15 2015 - 08:15:17 EST


From: Keith Busch <keith.busch@xxxxxxxxx>

Signed-off-by: Keith Busch <keith.busch@xxxxxxxxx>
[hch: rebased, set PTPL=1]
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
drivers/nvme/host/pci.c | 95 +++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 95 insertions(+)

diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
index ad58ee3..6230608 100644
--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c
@@ -39,8 +39,10 @@
#include <linux/slab.h>
#include <linux/t10-pi.h>
#include <linux/types.h>
+#include <linux/pr.h>
#include <scsi/sg.h>
#include <asm-generic/io-64-nonatomic-lo-hi.h>
+#include <asm/unaligned.h>

#include <uapi/linux/nvme_ioctl.h>
#include "nvme.h"
@@ -2058,6 +2060,98 @@ static int nvme_revalidate_disk(struct gendisk *disk)
return 0;
}

+static char nvme_pr_type(enum pr_type type)
+{
+ switch (type) {
+ case PR_WRITE_EXCLUSIVE:
+ return 1;
+ case PR_EXCLUSIVE_ACCESS:
+ return 2;
+ case PR_WRITE_EXCLUSIVE_REG_ONLY:
+ return 3;
+ case PR_EXCLUSIVE_ACCESS_REG_ONLY:
+ return 4;
+ case PR_WRITE_EXCLUSIVE_ALL_REGS:
+ return 5;
+ case PR_EXCLUSIVE_ACCESS_ALL_REGS:
+ return 6;
+ default:
+ return 0;
+ }
+};
+
+static int nvme_pr_command(struct block_device *bdev, u32 cdw10,
+ u64 key, u64 sa_key, u8 op)
+{
+ struct nvme_ns *ns = bdev->bd_disk->private_data;
+ struct nvme_command c;
+ u8 data[16] = { 0, };
+
+ put_unaligned_le64(key, &data[0]);
+ put_unaligned_le64(sa_key, &data[8]);
+
+ memset(&c, 0, sizeof(c));
+ c.common.opcode = op;
+ c.common.nsid = ns->ns_id;
+ c.common.cdw10[0] = cdw10;
+
+ return nvme_submit_sync_cmd(ns->queue, &c, data, 16);
+}
+
+static int nvme_pr_register(struct block_device *bdev, u64 old,
+ u64 new, unsigned flags)
+{
+ u32 cdw10;
+
+ if (flags & ~PR_FL_IGNORE_KEY)
+ return -EOPNOTSUPP;
+
+ cdw10 = old ? 2 : 0;
+ cdw10 |= (flags & PR_FL_IGNORE_KEY) ? 1 << 3 : 0;
+ cdw10 |= (1 << 30) | (1 << 31); /* PTPL=1 */
+ return nvme_pr_command(bdev, cdw10, old, new, nvme_cmd_resv_register);
+}
+
+static int nvme_pr_reserve(struct block_device *bdev, u64 key,
+ enum pr_type type, unsigned flags)
+{
+ u32 cdw10;
+
+ if (flags & ~PR_FL_IGNORE_KEY)
+ return -EOPNOTSUPP;
+
+ cdw10 = nvme_pr_type(type) << 8;
+ cdw10 |= ((flags & PR_FL_IGNORE_KEY) ? 1 << 3 : 0);
+ return nvme_pr_command(bdev, cdw10, key, 0, nvme_cmd_resv_acquire);
+}
+
+static int nvme_pr_preempt(struct block_device *bdev, u64 old, u64 new,
+ enum pr_type type, bool abort)
+{
+ u32 cdw10 = nvme_pr_type(type) << 8 | abort ? 2 : 1;
+ return nvme_pr_command(bdev, cdw10, old, new, nvme_cmd_resv_acquire);
+}
+
+static int nvme_pr_clear(struct block_device *bdev, u64 key)
+{
+ u32 cdw10 = 1 | key ? 1 << 3 : 0;
+ return nvme_pr_command(bdev, cdw10, key, 0, nvme_cmd_resv_register);
+}
+
+static int nvme_pr_release(struct block_device *bdev, u64 key, enum pr_type type)
+{
+ u32 cdw10 = nvme_pr_type(type) << 8 | key ? 1 << 3 : 0;
+ return nvme_pr_command(bdev, cdw10, key, 0, nvme_cmd_resv_release);
+}
+
+static 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,
+};
+
static const struct block_device_operations nvme_fops = {
.owner = THIS_MODULE,
.ioctl = nvme_ioctl,
@@ -2066,6 +2160,7 @@ static const struct block_device_operations nvme_fops = {
.release = nvme_release,
.getgeo = nvme_getgeo,
.revalidate_disk= nvme_revalidate_disk,
+ .pr_ops = &nvme_pr_ops,
};

static int nvme_kthread(void *data)
--
1.9.1

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