ioctl: Rearrange members in nvme_fw_commit_args

Avoid any holes in the struct by rearranging the members. Also add the
attribute packed to struct definition to reduce ABI breakage.

struct nvme_fw_commit_args {
        int                        args_size;            /*     0     4 */
        int                        fd;                   /*     4     4 */
        __u32 *                    result;               /*     8     8 */
        __u32                      timeout;              /*    16     4 */
        enum nvme_fw_commit_ca     action;               /*    20     4 */
        __u8                       slot;                 /*    24     1 */
        _Bool                      bpid;                 /*    25     1 */

        /* size: 32, cachelines: 1, members: 7 */
        /* padding: 6 */
        /* last cacheline: 32 bytes */
} __attribute__((__aligned__(8)));

Signed-off-by: Daniel Wagner <[email protected]>

Author: dwsuse

src/nvme/ioctl.h

@@ -2892,21 +2892,21 @@ int nvme_fw_download(struct nvme_fw_download_args *args);
 /**
  * nvme_fw_commit_args - Arguments for the NVMe Firmware Commit command
  * @fd:		File descriptor of nvme device
- * @slot:	Firmware slot to commit the downloaded image
  * @action:	Action to use for the firmware image, see &enum nvme_fw_commit_ca
- * @bpid:	Set to true to select the boot partition id
  * @timeout:	Timeout in ms
  * @result:	The command completion result from CQE dword0
+ * @slot:	Firmware slot to commit the downloaded image
+ * @bpid:	Set to true to select the boot partition id
  */
 struct nvme_fw_commit_args {
 	int args_size;
 	int fd;
-	__u8 slot;
+	__u32 *result;
+	__u32 timeout;
 	enum nvme_fw_commit_ca action;
+	__u8 slot;
 	bool bpid;
-	__u32 timeout;
-	__u32 *result;
-};
+} __attribute__((packed, aligned(__alignof__(__u32*))));
 
 /**
  * nvme_fw_commit() - Commit firmware using the specified action