From mboxrd@z Thu Jan 1 00:00:00 1970 From: Juergen Gross Subject: [Patch V3 07/15] xen: check memory area against e820 map Date: Mon, 20 Apr 2015 07:23:32 +0200 Message-ID: <1429507420-18201-8-git-send-email-jgross@suse.com> References: <1429507420-18201-1-git-send-email-jgross@suse.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1429507420-18201-1-git-send-email-jgross@suse.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: linux-kernel@vger.kernel.org, xen-devel@lists.xensource.com, konrad.wilk@oracle.com, david.vrabel@citrix.com, boris.ostrovsky@oracle.comlinux-mm, @kvack.org Cc: Juergen Gross List-Id: linux-mm.kvack.org Provide a service routine to check a physical memory area against the E820 map. The routine will return false if the complete area is RAM according to the E820 map and true otherwise. Signed-off-by: Juergen Gross Reviewed-by: David Vrabel --- arch/x86/xen/setup.c | 23 +++++++++++++++++++++++ arch/x86/xen/xen-ops.h | 1 + 2 files changed, 24 insertions(+) diff --git a/arch/x86/xen/setup.c b/arch/x86/xen/setup.c index 87251b4..99ef82c 100644 --- a/arch/x86/xen/setup.c +++ b/arch/x86/xen/setup.c @@ -573,6 +573,29 @@ static unsigned long __init xen_count_remap_pages(unsigned long max_pfn) return extra; } +bool __init xen_is_e820_reserved(phys_addr_t start, phys_addr_t size) +{ + struct e820entry *entry; + unsigned mapcnt; + phys_addr_t end; + + if (!size) + return false; + + end = start + size; + entry = xen_e820_map; + + for (mapcnt = 0; mapcnt < xen_e820_map_entries; mapcnt++) { + if (entry->type == E820_RAM && entry->addr <= start && + (entry->addr + entry->size) >= end) + return false; + + entry++; + } + + return true; +} + /* * Reserve Xen mfn_list. * See comment above "struct start_info" in diff --git a/arch/x86/xen/xen-ops.h b/arch/x86/xen/xen-ops.h index 9e195c6..c1385b8 100644 --- a/arch/x86/xen/xen-ops.h +++ b/arch/x86/xen/xen-ops.h @@ -39,6 +39,7 @@ void xen_reserve_top(void); void xen_mm_pin_all(void); void xen_mm_unpin_all(void); +bool __init xen_is_e820_reserved(phys_addr_t start, phys_addr_t size); unsigned long __ref xen_chk_extra_mem(unsigned long pfn); void __init xen_inv_extra_mem(void); void __init xen_remap_memory(void); -- 2.1.4