NVMe: Passthrough IOCTL for IO commands

The NVME_IOCTL_SUBMIT_IO only works for IO commands with block data
transfers and isn't usable for other NVMe commands like flush,
data set management, or any sort of vendor unique command. The
NVME_IOCTL_ADMIN_CMD, however, can easily be modified to accept arbitrary
IO commands in addition to arbitrary admin commands without breaking
backward compatibility. This patch just adds a new IOCTL to distinguish
if the driver should submit the command on an IO or Admin queue.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

1 files changed, 4 insertions, 1 deletions

diff --git a/include/uapi/linux/nvme.h b/include/uapi/linux/nvme.h
index 134518b0100b..97106556408f 100644
--- a/include/uapi/linux/nvme.h
+++ b/include/uapi/linux/nvme.h
@@ -503,7 +503,7 @@ struct nvme_user_io {
         __u16   appmask;
 };
 
-struct nvme_admin_cmd {
+struct nvme_passthru_cmd {
         __u8    opcode;
         __u8    flags;
         __u16   rsvd1;
@@ -524,8 +524,11 @@ struct nvme_admin_cmd {
         __u32   result;
 };
 
+#define nvme_admin_cmd nvme_passthru_cmd
+
 #define NVME_IOCTL_ID           _IO('N', 0x40)
 #define NVME_IOCTL_ADMIN_CMD    _IOWR('N', 0x41, struct nvme_admin_cmd)
 #define NVME_IOCTL_SUBMIT_IO    _IOW('N', 0x42, struct nvme_user_io)
+#define NVME_IOCTL_IO_CMD       _IOWR('N', 0x43, struct nvme_passthru_cmd)
 
 #endif /* _UAPI_LINUX_NVME_H */