[PATCH v6 05/18] scsi: Add support for block PR read keys/reservation
Mike Christie
michael.christie at oracle.com
Fri Apr 7 13:05:38 PDT 2023
This adds support in sd.c for the block PR read keys and read reservation
callouts, so upper layers like LIO can get the PR info that's been setup
using the existing pr callouts and return it to initiators.
Signed-off-by: Mike Christie <michael.christie at oracle.com>
Reviewed-by: Chaitanya Kulkarni <kch at nvidia.com>
Reviewed-by: Christoph Hellwig <hch at lst.de>
---
drivers/scsi/scsi_common.c | 21 +++++++++
drivers/scsi/sd.c | 91 ++++++++++++++++++++++++++++++++++++++
include/scsi/scsi_common.h | 1 +
include/scsi/scsi_proto.h | 5 +++
4 files changed, 118 insertions(+)
diff --git a/drivers/scsi/scsi_common.c b/drivers/scsi/scsi_common.c
index 11bf6c275d4e..b7a7a2eea887 100644
--- a/drivers/scsi/scsi_common.c
+++ b/drivers/scsi/scsi_common.c
@@ -64,6 +64,27 @@ const char *scsi_device_type(unsigned type)
}
EXPORT_SYMBOL(scsi_device_type);
+enum pr_type scsi_pr_type_to_block(enum scsi_pr_type type)
+{
+ switch (type) {
+ case SCSI_PR_WRITE_EXCLUSIVE:
+ return PR_WRITE_EXCLUSIVE;
+ case SCSI_PR_EXCLUSIVE_ACCESS:
+ return PR_EXCLUSIVE_ACCESS;
+ case SCSI_PR_WRITE_EXCLUSIVE_REG_ONLY:
+ return PR_WRITE_EXCLUSIVE_REG_ONLY;
+ case SCSI_PR_EXCLUSIVE_ACCESS_REG_ONLY:
+ return PR_EXCLUSIVE_ACCESS_REG_ONLY;
+ case SCSI_PR_WRITE_EXCLUSIVE_ALL_REGS:
+ return PR_WRITE_EXCLUSIVE_ALL_REGS;
+ case SCSI_PR_EXCLUSIVE_ACCESS_ALL_REGS:
+ return PR_EXCLUSIVE_ACCESS_ALL_REGS;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(scsi_pr_type_to_block);
+
enum scsi_pr_type block_pr_type_to_scsi(enum pr_type type)
{
switch (type) {
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index 256c582571fd..95fa0a486572 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -1723,6 +1723,95 @@ static int sd_scsi_to_pr_err(struct scsi_sense_hdr *sshdr, int result)
}
}
+static int sd_pr_in_command(struct block_device *bdev, u8 sa,
+ unsigned char *data, int data_len)
+{
+ struct scsi_disk *sdkp = scsi_disk(bdev->bd_disk);
+ struct scsi_device *sdev = sdkp->device;
+ struct scsi_sense_hdr sshdr;
+ u8 cmd[10] = { PERSISTENT_RESERVE_IN, sa };
+ const struct scsi_exec_args exec_args = {
+ .sshdr = &sshdr,
+ };
+ int result;
+
+ put_unaligned_be16(data_len, &cmd[7]);
+
+ result = scsi_execute_cmd(sdev, cmd, REQ_OP_DRV_IN, data, data_len,
+ SD_TIMEOUT, sdkp->max_retries, &exec_args);
+ if (scsi_status_is_check_condition(result) &&
+ scsi_sense_valid(&sshdr)) {
+ sdev_printk(KERN_INFO, sdev, "PR command failed: %d\n", result);
+ scsi_print_sense_hdr(sdev, NULL, &sshdr);
+ }
+
+ if (result <= 0)
+ return result;
+
+ return sd_scsi_to_pr_err(&sshdr, result);
+}
+
+static int sd_pr_read_keys(struct block_device *bdev, struct pr_keys *keys_info)
+{
+ int result, i, data_offset, num_copy_keys;
+ u32 num_keys = keys_info->num_keys;
+ int data_len = num_keys * 8 + 8;
+ u8 *data;
+
+ data = kzalloc(data_len, GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ result = sd_pr_in_command(bdev, READ_KEYS, data, data_len);
+ if (result)
+ goto free_data;
+
+ keys_info->generation = get_unaligned_be32(&data[0]);
+ keys_info->num_keys = get_unaligned_be32(&data[4]) / 8;
+
+ data_offset = 8;
+ num_copy_keys = min(num_keys, keys_info->num_keys);
+
+ for (i = 0; i < num_copy_keys; i++) {
+ keys_info->keys[i] = get_unaligned_be64(&data[data_offset]);
+ data_offset += 8;
+ }
+
+free_data:
+ kfree(data);
+ return result;
+}
+
+static int sd_pr_read_reservation(struct block_device *bdev,
+ struct pr_held_reservation *rsv)
+{
+ struct scsi_disk *sdkp = scsi_disk(bdev->bd_disk);
+ struct scsi_device *sdev = sdkp->device;
+ u8 data[24] = { };
+ int result, len;
+
+ result = sd_pr_in_command(bdev, READ_RESERVATION, data, sizeof(data));
+ if (result)
+ return result;
+
+ len = get_unaligned_be32(&data[4]);
+ if (!len)
+ return 0;
+
+ /* Make sure we have at least the key and type */
+ if (len < 14) {
+ sdev_printk(KERN_INFO, sdev,
+ "READ RESERVATION failed due to short return buffer of %d bytes\n",
+ len);
+ return -EINVAL;
+ }
+
+ rsv->generation = get_unaligned_be32(&data[0]);
+ rsv->key = get_unaligned_be64(&data[8]);
+ rsv->type = scsi_pr_type_to_block(data[21] & 0x0f);
+ return 0;
+}
+
static int sd_pr_out_command(struct block_device *bdev, u8 sa, u64 key,
u64 sa_key, enum scsi_pr_type type, u8 flags)
{
@@ -1804,6 +1893,8 @@ static const struct pr_ops sd_pr_ops = {
.pr_release = sd_pr_release,
.pr_preempt = sd_pr_preempt,
.pr_clear = sd_pr_clear,
+ .pr_read_keys = sd_pr_read_keys,
+ .pr_read_reservation = sd_pr_read_reservation,
};
static void scsi_disk_free_disk(struct gendisk *disk)
diff --git a/include/scsi/scsi_common.h b/include/scsi/scsi_common.h
index e25291bbbe9b..fb58715fac86 100644
--- a/include/scsi/scsi_common.h
+++ b/include/scsi/scsi_common.h
@@ -20,6 +20,7 @@ enum scsi_pr_type {
};
enum scsi_pr_type block_pr_type_to_scsi(enum pr_type type);
+enum pr_type scsi_pr_type_to_block(enum scsi_pr_type type);
static inline unsigned
scsi_varlen_cdb_length(const void *hdr)
diff --git a/include/scsi/scsi_proto.h b/include/scsi/scsi_proto.h
index fbe5bdfe4d6e..07d65c1f59db 100644
--- a/include/scsi/scsi_proto.h
+++ b/include/scsi/scsi_proto.h
@@ -151,6 +151,11 @@
#define ZO_FINISH_ZONE 0x02
#define ZO_OPEN_ZONE 0x03
#define ZO_RESET_WRITE_POINTER 0x04
+/* values for PR in service action */
+#define READ_KEYS 0x00
+#define READ_RESERVATION 0x01
+#define REPORT_CAPABILITES 0x02
+#define READ_FULL_STATUS 0x03
/* values for variable length command */
#define XDREAD_32 0x03
#define XDWRITE_32 0x04
--
2.25.1
More information about the Linux-nvme
mailing list