From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761167AbZCWSPm (ORCPT ); Mon, 23 Mar 2009 14:15:42 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1759736AbZCWSK1 (ORCPT ); Mon, 23 Mar 2009 14:10:27 -0400 Received: from adsl-69-107-72-54.dsl.pltn13.pacbell.net ([69.107.72.54]:60880 "EHLO abulafia.goop.org" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1760565AbZCWSKL (ORCPT ); Mon, 23 Mar 2009 14:10:11 -0400 From: Jeremy Fitzhardinge To: "H. Peter Anvin" Cc: the arch/x86 maintainers , Ingo Molnar , Linux Kernel Mailing List , Xen-devel , Ian Campbell , Jeremy Fitzhardinge Subject: [PATCH 08/15] xen/dom0: Use host E820 map Date: Mon, 23 Mar 2009 11:09:52 -0700 Message-Id: <1237831799-6568-9-git-send-email-jeremy@goop.org> X-Mailer: git-send-email 1.6.0.6 In-Reply-To: <49C45238.7050007@zytor.com> References: <49C45238.7050007@zytor.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Ian Campbell Impact: synthesize virtual E820 using real one as template Unlike the non-paravirt Xen port we do not have distinct psuedo-physical and I/O memory resource-spaces and therefore resources in the two can clash. Fix this by registering a memory map which matches the underlying I/O map. Currently this wastes the memory in the reserved regions. Eventually we should remap this memory to the end of the address space. Signed-off-by: Ian Campbell Signed-off-by: Jeremy Fitzhardinge --- arch/x86/xen/setup.c | 45 +++++++++++++++++++++++++++++++++++++-- include/xen/interface/memory.h | 29 +++++++++++++++++++++++++ 2 files changed, 71 insertions(+), 3 deletions(-) diff --git a/arch/x86/xen/setup.c b/arch/x86/xen/setup.c index 3e4cf46..175396c 100644 --- a/arch/x86/xen/setup.c +++ b/arch/x86/xen/setup.c @@ -19,6 +19,7 @@ #include #include +#include #include #include @@ -36,16 +37,54 @@ extern void xen_syscall32_target(void); /** * machine_specific_memory_setup - Hook for machine specific memory setup. **/ - char * __init xen_memory_setup(void) { unsigned long max_pfn = xen_start_info->nr_pages; + unsigned long long mem_end; + int rc; + struct xen_memory_map memmap; + /* + * This is rather large for a stack variable but this early in + * the boot process we know we have plenty slack space. + */ + struct e820entry map[E820MAX]; + int op = xen_initial_domain() ? + XENMEM_machine_memory_map : + XENMEM_memory_map; + int i; max_pfn = min(MAX_DOMAIN_PAGES, max_pfn); + mem_end = PFN_PHYS((u64)max_pfn); + + memmap.nr_entries = E820MAX; + set_xen_guest_handle(memmap.buffer, map); + + rc = HYPERVISOR_memory_op(op, &memmap); + if (rc == -ENOSYS) { + memmap.nr_entries = 1; + map[0].addr = 0ULL; + map[0].size = mem_end; + /* 8MB slack (to balance backend allocations). */ + map[0].size += 8ULL << 20; + map[0].type = E820_RAM; + rc = 0; + } + BUG_ON(rc); e820.nr_map = 0; - - e820_add_region(0, PFN_PHYS((u64)max_pfn), E820_RAM); + for (i = 0; i < memmap.nr_entries; i++) { + unsigned long long end = map[i].addr + map[i].size; + if (map[i].type == E820_RAM) { + if (map[i].addr > mem_end) + continue; + if (end > mem_end) { + /* Truncate region to max_mem. */ + map[i].size -= end - mem_end; + } + } + if (map[i].size > 0) + e820_add_region(map[i].addr, map[i].size, map[i].type); + } /* * Even though this is normal, usable memory under Xen, reserve diff --git a/include/xen/interface/memory.h b/include/xen/interface/memory.h index af36ead..e6c6bcb 100644 --- a/include/xen/interface/memory.h +++ b/include/xen/interface/memory.h @@ -142,4 +142,33 @@ struct xen_translate_gpfn_list { }; DEFINE_GUEST_HANDLE_STRUCT(xen_translate_gpfn_list); +/* + * Returns the pseudo-physical memory map as it was when the domain + * was started (specified by XENMEM_set_memory_map). + * arg == addr of struct xen_memory_map. + */ +#define XENMEM_memory_map 9 +struct xen_memory_map { + /* + * On call the number of entries which can be stored in buffer. On + * return the number of entries which have been stored in + * buffer. + */ + unsigned int nr_entries; + + /* + * Entries in the buffer are in the same format as returned by the + * BIOS INT 0x15 EAX=0xE820 call. + */ + GUEST_HANDLE(void) buffer; +}; +DEFINE_GUEST_HANDLE_STRUCT(xen_memory_map); + +/* + * Returns the real physical memory map. Passes the same structure as + * XENMEM_memory_map. + * arg == addr of struct xen_memory_map. + */ +#define XENMEM_machine_memory_map 10 + #endif /* __XEN_PUBLIC_MEMORY_H__ */ -- 1.6.0.6