diff mbox series

[v2,2/4] cxl/uapi: Add warning on CXL command enum

Message ID 20221222-cxl-misc-v2-2-60403cc37257@intel.com
State Superseded
Headers show
Series CXL: Miscellaneous fixes | expand

Commit Message

Ira Weiny Jan. 28, 2023, 12:09 a.m. UTC 
The CXL command enum is exported to user space and must maintain
backwards compatibility.

Add comment that new defines must be added to the end of the list.

Suggested-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>

---
Changes for v2:
	Pick up tag
---
 include/uapi/linux/cxl_mem.h | 4 ++++
 1 file changed, 4 insertions(+)

Comments

Dave Jiang Jan. 31, 2023, 4:24 p.m. UTC | #1 
On 1/27/23 5:09 PM, Ira Weiny wrote:
> The CXL command enum is exported to user space and must maintain
> backwards compatibility.
> 
> Add comment that new defines must be added to the end of the list.
> 
> Suggested-by: Dan Williams <dan.j.williams@intel.com>
> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
> Signed-off-by: Ira Weiny <ira.weiny@intel.com>

Reviewed-by: Dave Jiang <dave.jiang@intel.com>

> 
> ---
> Changes for v2:
> 	Pick up tag
> ---
>   include/uapi/linux/cxl_mem.h | 4 ++++
>   1 file changed, 4 insertions(+)
> 
> diff --git a/include/uapi/linux/cxl_mem.h b/include/uapi/linux/cxl_mem.h
> index c71021a2a9ed..459a3f7f764b 100644
> --- a/include/uapi/linux/cxl_mem.h
> +++ b/include/uapi/linux/cxl_mem.h
> @@ -19,6 +19,10 @@
>   #define CXL_MEM_QUERY_COMMANDS _IOR(0xCE, 1, struct cxl_mem_query_commands)
>   #define CXL_MEM_SEND_COMMAND _IOWR(0xCE, 2, struct cxl_send_command)
>   
> +/*
> + * NOTE: New defines must be added to the end of the list to preserve
> + * compatibility because this enum is exported to user space.
> + */
>   #define CXL_CMDS                                                          \
>   	___C(INVALID, "Invalid Command"),                                 \
>   	___C(IDENTIFY, "Identify Command"),                               \
>
diff mbox series

Patch

diff --git a/include/uapi/linux/cxl_mem.h b/include/uapi/linux/cxl_mem.h
index c71021a2a9ed..459a3f7f764b 100644
--- a/include/uapi/linux/cxl_mem.h
+++ b/include/uapi/linux/cxl_mem.h
@@ -19,6 +19,10 @@ 
 #define CXL_MEM_QUERY_COMMANDS _IOR(0xCE, 1, struct cxl_mem_query_commands)
 #define CXL_MEM_SEND_COMMAND _IOWR(0xCE, 2, struct cxl_send_command)
 
+/*
+ * NOTE: New defines must be added to the end of the list to preserve
+ * compatibility because this enum is exported to user space.
+ */
 #define CXL_CMDS                                                          \
 	___C(INVALID, "Invalid Command"),                                 \
 	___C(IDENTIFY, "Identify Command"),                               \