Re: [PATCH 1/3] block: Add error codes for common PR failures

Christoph Hellwig
2022-11-09T06:52:26Z

On Tue, Nov 08, 2022 at 09:11:04PM -0600, Mike Christie wrote:
> If a PR operation fails we can return a device specific error which is
> impossible to handle in some cases because we could have a mix of devices
> when DM is used, or future users like lio only know it's interacting with
> a block device so it doesn't know the type.
>
> This patch adds a new pr_status enum so drivers can convert errors to a
> common type which can be handled by the caller.
>
> Signed-off-by: Mike Christie <michael.christie@oracle.com>
> ---
> include/uapi/linux/pr.h | 24 ++++++++++++++++++++++++
> 1 file changed, 24 insertions(+)
>
> diff --git a/include/uapi/linux/pr.h b/include/uapi/linux/pr.h
> index ccc78cbf1221..16b856fb8053 100644
> --- a/include/uapi/linux/pr.h
> +++ b/include/uapi/linux/pr.h
> @@ -4,6 +4,30 @@
>
> #include <linux/types.h>
>
> +enum pr_status {
> + PR_STS_SUCCESS = 0x0,
> + /*
> + * These error codes have no mappings to existing SCSI errors.
> + */
> + /* The request is not supported. */
> + PR_STS_OP_NOT_SUPP = 0x7fffffff,
> + /* The request is invalid/illegal. */
> + PR_STS_OP_INVALID = 0x7ffffffe,
> + /*
> + * The following error codes are based on SCSI, because the interface
> + * was originally created for it and has existing users.
> + */
> + /* Generic device failure. */
> + PR_STS_IOERR = 0x2,
> + PR_STS_RESERVATION_CONFLICT = 0x18,
> + /* Temporary path failure that can be retried. */
> + PR_STS_RETRY_PATH_FAILURE = 0xe0000,
> + /* The request was failed due to a fast failure timer. */
> + PR_STS_PATH_FAST_FAILED = 0xf0000,
> + /* The path cannot be reached and has been marked as failed. */
> + PR_STS_PATH_FAILED = 0x10000,

Nit: I'd movee the NOT_SUPP/INVALID to the end to follow the numerical
order.

Otherwise looks good:

Reviewed-by: Christoph Hellwig <hch@lst.de>