From mboxrd@z Thu Jan 1 00:00:00 1970 From: Julien Grall Subject: [PATCH v2] xen/arm: ioremap_attr: return NULL is __vmap failed Date: Mon, 18 Nov 2013 13:08:23 +0000 Message-ID: <1384780103-10183-1-git-send-email-julien.grall@linaro.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mail6.bemta4.messagelabs.com ([85.158.143.247]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1ViOZ4-0003AS-Fu for xen-devel@lists.xenproject.org; Mon, 18 Nov 2013 13:08:30 +0000 Received: by mail-wi0-f172.google.com with SMTP id en1so1920555wid.17 for ; Mon, 18 Nov 2013 05:08:29 -0800 (PST) List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: xen-devel@lists.xenproject.org Cc: stefano.stabellini@eu.citrix.com, tim@xen.org, ian.campbell@citrix.com, Julien Grall , patches@linaro.org List-Id: xen-devel@lists.xenproject.org Most of ioremap_* caller check if ioremap returns NULL. Actually, if the physical address is non-aligned, Xen will return the pointer given by __vmap plus the offset in the page. So if ioremap_* fails, the caller will retrieve an non-NULL address and continue as if there was no error. Signed-off-by: Julien Grall Acked-by: Stefano Stabellini --- Changes in v2: - remove brackets for return - don't split declaration and initialisation of ptr --- xen/arch/arm/mm.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/xen/arch/arm/mm.c b/xen/arch/arm/mm.c index 26c6768..d5b22a4 100644 --- a/xen/arch/arm/mm.c +++ b/xen/arch/arm/mm.c @@ -742,8 +742,12 @@ void *ioremap_attr(paddr_t pa, size_t len, unsigned int attributes) unsigned long pfn = PFN_DOWN(pa); unsigned int offs = pa & (PAGE_SIZE - 1); unsigned int nr = PFN_UP(offs + len); + void *ptr = __vmap(&pfn, nr, 1, 1, attributes); - return (__vmap(&pfn, nr, 1, 1, attributes) + offs); + if ( ptr == NULL ) + return NULL; + + return ptr + offs; } void *ioremap(paddr_t pa, size_t len) -- 1.8.3.1