Re: [Xen-devel] [PATCH v1 4/6] xen: use errno instead of rc for xc_domain_add_to_physmap

[Stefano Stabellini <stefano.stabellini@xxxxxxxxxxxxx>]

On Thu, 2 Jul 2015, Konrad Rzeszutek Wilk wrote:
> In Xen 4.6 commit cd2f100f0f61b3f333d52d1737dd73f02daee592
> "libxc: Fix do_memory_op to return negative value on errors"
> made the libxc API less odd-ball: On errors, return value is
> -1 and error code is in errno. On success the return value
> is either 0 or an positive value.
> 
> Since we could be running with an old toolstack in which the
> Exx value is in rc or the newer, we add an wrapper around
> the xc_domain_add_to_physmap (called xen_xc_domain_add_to_physmap)
> which will always return the EXX.
> 
> Suggested-by: Stefano Stabellini <stefano.stabellini@xxxxxxxxxxxxx>
> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@xxxxxxxxxx>
> ---
>  include/hw/xen/xen_common.h | 22 ++++++++++++++++++++++
>  xen-hvm.c                   |  4 ++--
>  2 files changed, 24 insertions(+), 2 deletions(-)
> 
> diff --git a/include/hw/xen/xen_common.h b/include/hw/xen/xen_common.h
> index 38f29fb..fc66c3c 100644
> --- a/include/hw/xen/xen_common.h
> +++ b/include/hw/xen/xen_common.h
> @@ -407,4 +407,26 @@ static inline int xen_set_ioreq_server_state(XenXC xc, 
> domid_t dom,
>  
>  #endif
>  
> +#if CONFIG_XEN_CTRL_INTERFACE_VERSION < 460

This patch is fine as is and you can add my

Reviewed-by: Stefano Stabellini <stefano.stabellini@xxxxxxxxxxxxx>

however there is no code to detect 460 at the moment, see
configure:1844. We need one more test case in the configure script to
detect 4.6.


> +static inline int xen_xc_domain_add_to_physmap(XenXC xch, uint32_t domid,
> +                                               unsigned int space,
> +                                               unsigned long idx,
> +                                               xen_pfn_t gpfn)
> +{
> +    return xc_domain_add_to_physmap(xch, domid, space, idx, gpfn);
> +}
> +#else
> +static inline int xen_xc_domain_add_to_physmap(XenXC xch, uint32_t domid,
> +                                               unsigned int space,
> +                                               unsigned long idx,
> +                                               xen_pfn_t gpfn)
> +{
> +    /* In Xen 4.6 rc is -1 and errno contains the error value. */
> +    int rc = xc_domain_add_to_physmap(xch, domid, space, idx, gpfn);
> +    if (rc == -1)
> +        return errno;
> +    return rc;
> +}
> +#endif
> +
>  #endif /* QEMU_HW_XEN_COMMON_H */
> diff --git a/xen-hvm.c b/xen-hvm.c
> index 0408462..fae2d22 100644
> --- a/xen-hvm.c
> +++ b/xen-hvm.c
> @@ -345,7 +345,7 @@ go_physmap:
>          unsigned long idx = pfn + i;
>          xen_pfn_t gpfn = start_gpfn + i;
>  
> -        rc = xc_domain_add_to_physmap(xen_xc, xen_domid, XENMAPSPACE_gmfn, 
> idx, gpfn);
> +        rc = xen_xc_domain_add_to_physmap(xen_xc, xen_domid, 
> XENMAPSPACE_gmfn, idx, gpfn);
>          if (rc) {
>              DPRINTF("add_to_physmap MFN %"PRI_xen_pfn" to PFN %"
>                      PRI_xen_pfn" failed: %d\n", idx, gpfn, rc);
> @@ -422,7 +422,7 @@ static int xen_remove_from_physmap(XenIOState *state,
>          xen_pfn_t idx = start_addr + i;
>          xen_pfn_t gpfn = phys_offset + i;
>  
> -        rc = xc_domain_add_to_physmap(xen_xc, xen_domid, XENMAPSPACE_gmfn, 
> idx, gpfn);
> +        rc = xen_xc_domain_add_to_physmap(xen_xc, xen_domid, 
> XENMAPSPACE_gmfn, idx, gpfn);
>          if (rc) {
>              fprintf(stderr, "add_to_physmap MFN %"PRI_xen_pfn" to PFN %"
>                      PRI_xen_pfn" failed: %d\n", idx, gpfn, rc);
> -- 
> 2.1.0
> 

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel