Re: [PATCH 14/14] xen/mm: Provide dummy M2P-related helpers when !CONFIG_HAVE_M2P

From: Stefano Stabellini <sstabellini@kernel.org>
To: Julien Grall <julien.grall@arm.com>
Cc: Stefano Stabellini <sstabellini@kernel.org>,
	Wei Liu <wei.liu2@citrix.com>,
	Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>,
	George Dunlap <George.Dunlap@eu.citrix.com>,
	Andrew Cooper <andrew.cooper3@citrix.com>,
	Ian Jackson <ian.jackson@eu.citrix.com>, Tim Deegan <tim@xen.org>,
	Jan Beulich <jbeulich@suse.com>,
	xen-devel@lists.xenproject.org
Subject: Re: [PATCH 14/14] xen/mm: Provide dummy M2P-related helpers when !CONFIG_HAVE_M2P
Date: Thu, 9 May 2019 11:20:53 -0700 (PDT)	[thread overview]
Message-ID: <alpine.DEB.2.21.1905091120440.25766@sstabellini-ThinkPad-T480s> (raw)
In-Reply-To: <20190507151458.29350-15-julien.grall@arm.com>

On Tue, 7 May 2019, Julien Grall wrote:
> At the moment, Arm is providing a dummy implementation for the M2P
> helpers used in common code. However, they are quite isolated and could
> be used by other architecture in the future. So move all the helpers in
> xen/mm.h.
> 
> Signed-off-by: Julien Grall <julien.grall@arm.com>

Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>


> ---
>     Changes in v2:
>         - Patch added
> ---
>  xen/include/asm-arm/mm.h | 11 -----------
>  xen/include/xen/mm.h     | 14 ++++++++++++++
>  2 files changed, 14 insertions(+), 11 deletions(-)
> 
> diff --git a/xen/include/asm-arm/mm.h b/xen/include/asm-arm/mm.h
> index 3c03be3bca..d68d1794e5 100644
> --- a/xen/include/asm-arm/mm.h
> +++ b/xen/include/asm-arm/mm.h
> @@ -313,17 +313,6 @@ static inline void *page_to_virt(const struct page_info *pg)
>  struct page_info *get_page_from_gva(struct vcpu *v, vaddr_t va,
>                                      unsigned long flags);
>  
> -/*
> - * Arm does not have an M2P, but common code expects a handful of
> - * M2P-related defines and functions. Provide dummy versions of these.
> - */
> -#define INVALID_M2P_ENTRY        (~0UL)
> -#define SHARED_M2P_ENTRY         (~0UL - 1UL)
> -#define SHARED_M2P(_e)           ((_e) == SHARED_M2P_ENTRY)
> -
> -/* We don't have a M2P on Arm */
> -static inline void set_pfn_from_mfn(mfn_t mfn, unsigned long pfn) {}
> -
>  /* Arch-specific portion of memory_op hypercall. */
>  long arch_memory_op(int op, XEN_GUEST_HANDLE_PARAM(void) arg);
>  
> diff --git a/xen/include/xen/mm.h b/xen/include/xen/mm.h
> index 3ba7168cc9..07d2d44491 100644
> --- a/xen/include/xen/mm.h
> +++ b/xen/include/xen/mm.h
> @@ -658,4 +658,18 @@ static inline void share_xen_page_with_privileged_guests(
>      share_xen_page_with_guest(page, dom_xen, flags);
>  }
>  
> +/*
> + * Dummy implementation of M2P-related helpers for common code when
> + * the architecture doesn't have an M2P.
> + */
> +#ifndef CONFIG_HAS_M2P
> +
> +#define INVALID_M2P_ENTRY        (~0UL)
> +#define SHARED_M2P_ENTRY         (~0UL - 1UL)
> +#define SHARED_M2P(_e)           ((_e) == SHARED_M2P_ENTRY)
> +
> +static inline void set_pfn_from_mfn(mfn_t mfn, unsigned long pfn) {}
> +
> +#endif
> +
>  #endif /* __XEN_MM_H__ */
> -- 
> 2.11.0
> 

_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xenproject.org
https://lists.xenproject.org/mailman/listinfo/xen-devel