[PATCH v3 10/19] nvme: Move NVMe and Block PR types to an array

[Mike Christie]

For Reservation Report support we need to also convert from the NVMe spec
PR type back to the block PR definition. This moves us to an array, so in
the next patch we can add another helper to do the conversion without
having to manage 2 switches.

Signed-off-by: Mike Christie <michael.christie at oracle.com>
---
 drivers/nvme/host/pr.c | 42 +++++++++++++++++++++++-------------------
 include/linux/nvme.h   |  9 +++++++++
 2 files changed, 32 insertions(+), 19 deletions(-)

diff --git a/drivers/nvme/host/pr.c b/drivers/nvme/host/pr.c
index df7eb2440c67..5c4611d15d9c 100644
--- a/drivers/nvme/host/pr.c
+++ b/drivers/nvme/host/pr.c
@@ -6,24 +6,28 @@
 
 #include "nvme.h"
 
-static char nvme_pr_type(enum pr_type type)
+static const struct {
+	enum nvme_pr_type	nvme_type;
+	enum pr_type		blk_type;
+} nvme_pr_types[] = {
+	{ NVME_PR_WRITE_EXCLUSIVE, PR_WRITE_EXCLUSIVE },
+	{ NVME_PR_EXCLUSIVE_ACCESS, PR_EXCLUSIVE_ACCESS },
+	{ NVME_PR_WRITE_EXCLUSIVE_REG_ONLY, PR_WRITE_EXCLUSIVE_REG_ONLY },
+	{ NVME_PR_EXCLUSIVE_ACCESS_REG_ONLY, PR_EXCLUSIVE_ACCESS_REG_ONLY },
+	{ NVME_PR_WRITE_EXCLUSIVE_ALL_REGS, PR_WRITE_EXCLUSIVE_ALL_REGS },
+	{ NVME_PR_EXCLUSIVE_ACCESS_ALL_REGS, PR_EXCLUSIVE_ACCESS_ALL_REGS },
+};
+
+static enum nvme_pr_type nvme_pr_type_from_blk(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;
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(nvme_pr_types); i++) {
+		if (nvme_pr_types[i].blk_type == type)
+			return nvme_pr_types[i].nvme_type;
 	}
+
+	return 0;
 }
 
 static int nvme_send_ns_head_pr_command(struct block_device *bdev,
@@ -91,7 +95,7 @@ static int nvme_pr_reserve(struct block_device *bdev, u64 key,
 	if (flags & ~PR_FL_IGNORE_KEY)
 		return -EOPNOTSUPP;
 
-	cdw10 = nvme_pr_type(type) << 8;
+	cdw10 = nvme_pr_type_from_blk(type) << 8;
 	cdw10 |= ((flags & PR_FL_IGNORE_KEY) ? 1 << 3 : 0);
 	return nvme_pr_command(bdev, cdw10, key, 0, nvme_cmd_resv_acquire);
 }
@@ -99,7 +103,7 @@ static int nvme_pr_reserve(struct block_device *bdev, u64 key,
 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);
+	u32 cdw10 = nvme_pr_type_from_blk(type) << 8 | (abort ? 2 : 1);
 
 	return nvme_pr_command(bdev, cdw10, old, new, nvme_cmd_resv_acquire);
 }
@@ -113,7 +117,7 @@ static int nvme_pr_clear(struct block_device *bdev, u64 key)
 
 static int nvme_pr_release(struct block_device *bdev, u64 key, enum pr_type type)
 {
-	u32 cdw10 = nvme_pr_type(type) << 8 | (key ? 0 : 1 << 3);
+	u32 cdw10 = nvme_pr_type_from_blk(type) << 8 | (key ? 0 : 1 << 3);
 
 	return nvme_pr_command(bdev, cdw10, key, 0, nvme_cmd_resv_release);
 }
diff --git a/include/linux/nvme.h b/include/linux/nvme.h
index 5bc9c84dc216..d0bd15f527fc 100644
--- a/include/linux/nvme.h
+++ b/include/linux/nvme.h
@@ -757,6 +757,15 @@ enum {
 	NVME_LBART_ATTRIB_HIDE	= 1 << 1,
 };
 
+enum nvme_pr_type {
+	NVME_PR_WRITE_EXCLUSIVE			= 1,
+	NVME_PR_EXCLUSIVE_ACCESS		= 2,
+	NVME_PR_WRITE_EXCLUSIVE_REG_ONLY	= 3,
+	NVME_PR_EXCLUSIVE_ACCESS_REG_ONLY	= 4,
+	NVME_PR_WRITE_EXCLUSIVE_ALL_REGS	= 5,
+	NVME_PR_EXCLUSIVE_ACCESS_ALL_REGS	= 6,
+};
+
 enum nvme_eds {
 	NVME_EXTENDED_DATA_STRUCT	= 0x1,
 };
-- 
2.25.1