This is a mostly trivial mapping to the PERSISTENT RESERVE IN/OUT
commands.
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
drivers/scsi/sd.c | 90 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 90 insertions(+)
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index 160e44e..14bc2d7 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -51,6 +51,7 @@
#include <linux/async.h>
#include <linux/slab.h>
#include <linux/pm_runtime.h>
+#include <linux/pr.h>
#include <asm/uaccess.h>
#include <asm/unaligned.h>
@@ -1535,6 +1536,94 @@ static int sd_compat_ioctl(struct block_device *bdev, fmode_t mode,
}
#endif
+static char sd_pr_type(enum pr_type type)
+{
+ switch (type) {
+ case PR_WRITE_EXCLUSIVE:
+ return 0x01;
+ case PR_EXCLUSIVE_ACCESS:
+ return 0x03;
+ case PR_WRITE_EXCLUSIVE_REG_ONLY:
+ return 0x05;
+ case PR_EXCLUSIVE_ACCESS_REG_ONLY:
+ return 0x06;
+ case PR_WRITE_EXCLUSIVE_ALL_REGS:
+ return 0x07;
+ case PR_EXCLUSIVE_ACCESS_ALL_REGS:
+ return 0x08;
+ default:
+ return 0;
+ }
+};
+
+static int sd_pr_command(struct block_device *bdev, u8 sa,
+ u64 key, u64 sa_key, u8 type, u8 flags)
+{
+ struct scsi_device *sdev = scsi_disk(bdev->bd_disk)->device;
+ struct scsi_sense_hdr sshdr;
+ int result;
+ u8 cmd[16] = { 0, };
+ u8 data[24] = { 0, };
+
+ cmd[0] = PERSISTENT_RESERVE_OUT;
+ cmd[1] = sa;
+ cmd[2] = type;
+ put_unaligned_be32(sizeof(data), &cmd[5]);
+
+ put_unaligned_be64(key, &data[0]);
+ put_unaligned_be64(sa_key, &data[8]);
+ data[20] = flags;
+
+ result = scsi_execute_req(sdev, cmd, DMA_TO_DEVICE, &data, sizeof(data),
+ &sshdr, SD_TIMEOUT, SD_MAX_RETRIES, NULL);
+
+ if ((driver_byte(result) & DRIVER_SENSE) &&
+ (scsi_sense_valid(&sshdr))) {
+ sdev_printk(KERN_INFO, sdev, "PR command failed: %d\n", result);
+ scsi_print_sense_hdr(sdev, NULL, &sshdr);
+ }
+
+ return result;
+}
+
+static int sd_pr_register(struct block_device *bdev, u64 old_key, u64 new_key,
+ bool ignore)
+{
+ return sd_pr_command(bdev, ignore ? 0x06 : 0x00, old_key, new_key, 0,
+ (1 << 0) /* APTPL */ |
+ (1 << 2) /* ALL_TG_PT */);
+}
+
+static int sd_pr_reserve(struct block_device *bdev, u64 key, enum pr_type type)
+{
+ return sd_pr_command(bdev, 0x01, key, 0, sd_pr_type(type), 0);
+}
+
+static int sd_pr_release(struct block_device *bdev, u64 key, enum pr_type type)
+{
+ return sd_pr_command(bdev, 0x02, key, 0, sd_pr_type(type), 0);
+}
+
+static int sd_pr_preempt(struct block_device *bdev, u64 old_key, u64 new_key,
+ enum pr_type type, bool abort)
+{
+ return sd_pr_command(bdev, abort ? 0x05 : 0x04, old_key, new_key,
+ sd_pr_type(type), 0);
+}
+
+static int sd_pr_clear(struct block_device *bdev, u64 key)
+{
+ return sd_pr_command(bdev, 0x03, key, 0, 0, 0);
+}
+
+static const struct pr_ops sd_pr_ops = {
+ .pr_register = sd_pr_register,
+ .pr_reserve = sd_pr_reserve,
+ .pr_release = sd_pr_release,
+ .pr_preempt = sd_pr_preempt,
+ .pr_clear = sd_pr_clear,
+};
+
static const struct block_device_operations sd_fops = {
.owner = THIS_MODULE,
.open = sd_open,
@@ -1547,6 +1636,7 @@ static const struct block_device_operations sd_fops = {
.check_events = sd_check_events,
.revalidate_disk = sd_revalidate_disk,
.unlock_native_capacity = sd_unlock_native_capacity,
+ .pr_ops = &sd_pr_ops,
};
/**
--
1.9.1
--
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