Merge branch 'for-4.4/reservations' of git://git.kernel.dk/linux-block

Pull block reservation support from Jens Axboe:
 "This adds support for persistent reservations, both at the core level,
  as well as for sd and NVMe"

[ Background from the docs: "Persistent Reservations allow restricting
  access to block devices to specific initiators in a shared storage
  setup.  All implementations are expected to ensure the reservations
  survive a power loss and cover all connections in a multi path
  environment" ]

* 'for-4.4/reservations' of git://git.kernel.dk/linux-block:
  NVMe: Precedence error in nvme_pr_clear()
  nvme: add missing endianess annotations in nvme_pr_command
  NVMe: Add persistent reservation ops
  sd: implement the Persistent Reservation API
  block: add an API for Persistent Reservations
  block: cleanup blkdev_ioctl

1 files changed, 48 insertions, 0 deletions

diff --git a/include/uapi/linux/pr.h b/include/uapi/linux/pr.h
new file mode 100644
index 000000000000..57d7c0f916b6
--- /dev/null
+++ b/include/uapi/linux/pr.h
@@ -0,0 +1,48 @@
+#ifndef _UAPI_PR_H
+#define _UAPI_PR_H
+
+enum pr_type {
+        PR_WRITE_EXCLUSIVE              = 1,
+        PR_EXCLUSIVE_ACCESS             = 2,
+        PR_WRITE_EXCLUSIVE_REG_ONLY     = 3,
+        PR_EXCLUSIVE_ACCESS_REG_ONLY    = 4,
+        PR_WRITE_EXCLUSIVE_ALL_REGS     = 5,
+        PR_EXCLUSIVE_ACCESS_ALL_REGS    = 6,
+};
+
+struct pr_reservation {
+        __u64   key;
+        __u32   type;
+        __u32   flags;
+};
+
+struct pr_registration {
+        __u64   old_key;
+        __u64   new_key;
+        __u32   flags;
+        __u32   __pad;
+};
+
+struct pr_preempt {
+        __u64   old_key;
+        __u64   new_key;
+        __u32   type;
+        __u32   flags;
+};
+
+struct pr_clear {
+        __u64   key;
+        __u32   flags;
+        __u32   __pad;
+};
+
+#define PR_FL_IGNORE_KEY        (1 << 0)        /* ignore existing key */
+
+#define IOC_PR_REGISTER         _IOW('p', 200, struct pr_registration)
+#define IOC_PR_RESERVE          _IOW('p', 201, struct pr_reservation)
+#define IOC_PR_RELEASE          _IOW('p', 202, struct pr_reservation)
+#define IOC_PR_PREEMPT          _IOW('p', 203, struct pr_preempt)
+#define IOC_PR_PREEMPT_ABORT    _IOW('p', 204, struct pr_preempt)
+#define IOC_PR_CLEAR            _IOW('p', 205, struct pr_clear)
+
+#endif /* _UAPI_PR_H */