From: Don Slutz Date: Tue, 21 Oct 2014 12:42:26 +0000 (-0400) Subject: x86: hvm: Allow configuration of the size of the mmio_hole. X-Git-Tag: archive/raspbian/4.8.0-1+rpi1~1^2~4142 X-Git-Url: https://dgit.raspbian.org/%22http:/www.example.com/cgi/%22https:/%22bookmarks://%22/%22http:/www.example.com/cgi/%22https:/%22bookmarks:/%22?a=commitdiff_plain;h=2d927fc41b8e130b3b8910e4442d4691111d2ac7;p=xen.git x86: hvm: Allow configuration of the size of the mmio_hole. If you add enough PCI devices then all mmio may not fit below 4G which may not be the layout the user wanted. This allows you to increase the below 4G address space that PCI devices can use and therefore in more cases not have any mmio that is above 4G. There are real PCI cards that do not support mmio over 4G, so if you want to emulate them precisely, you may also need to increase the space below 4G for them. There are drivers for these cards that also do not work if they have their mmio space mapped above 4G. This allows growing the MMIO hole to the size needed. This may help with using pci passthru and HVM. In the tools this is named mmio_hole_memkb. Signed-off-by: Don Slutz Acked-by: George Dunlap Acked-by: Ian Campbell [ ijc -- fixed build error in xl_cmdimpl.c with s/%PRIu64/%ld/. Reworded title ] --- diff --git a/docs/man/xl.cfg.pod.5 b/docs/man/xl.cfg.pod.5 index 5830e09017..622ea53d91 100644 --- a/docs/man/xl.cfg.pod.5 +++ b/docs/man/xl.cfg.pod.5 @@ -1164,6 +1164,21 @@ wallclock (i.e., real) time. =back +=head3 Memory layout + +=over 4 + +=item B + +Specifies the size the MMIO hole below 4GiB will be. Only valid for +device_model_version = "qemu-xen". + +Cannot be smaller than 256. Cannot be larger than 3840. + +Known good large value is 3072. + +=back + =head3 Support for Paravirtualisation of HVM Guests The following options allow Paravirtualised features (such as devices) diff --git a/tools/firmware/hvmloader/config.h b/tools/firmware/hvmloader/config.h index 80bea46d28..b838cf9c17 100644 --- a/tools/firmware/hvmloader/config.h +++ b/tools/firmware/hvmloader/config.h @@ -53,7 +53,6 @@ extern struct bios_config ovmf_config; #define PCI_ISA_IRQ_MASK 0x0c20U /* ISA IRQs 5,10,11 are PCI connected */ /* MMIO hole: Hardcoded defaults, which can be dynamically expanded. */ -#define PCI_MEM_START 0xf0000000 #define PCI_MEM_END 0xfc000000 extern unsigned long pci_mem_start, pci_mem_end; diff --git a/tools/firmware/hvmloader/pci.c b/tools/firmware/hvmloader/pci.c index 3712988e64..4e8d803b79 100644 --- a/tools/firmware/hvmloader/pci.c +++ b/tools/firmware/hvmloader/pci.c @@ -28,9 +28,10 @@ #include #include #include +#include #include -unsigned long pci_mem_start = PCI_MEM_START; +unsigned long pci_mem_start = HVM_BELOW_4G_MMIO_START; unsigned long pci_mem_end = PCI_MEM_END; uint64_t pci_hi_mem_start = 0, pci_hi_mem_end = 0; @@ -59,6 +60,7 @@ void pci_setup(void) uint64_t bar_sz; } *bars = (struct bars *)scratch_start; unsigned int i, nr_bars = 0; + uint64_t mmio_hole_size = 0; const char *s; /* @@ -86,6 +88,10 @@ void pci_setup(void) printf("Relocating guest memory for lowmem MMIO space %s\n", allow_memory_relocate?"enabled":"disabled"); + s = xenstore_read("platform/mmio_hole_size", NULL); + if ( s ) + mmio_hole_size = strtoll(s, NULL, 0); + /* Program PCI-ISA bridge with appropriate link routes. */ isa_irq = 0; for ( link = 0; link < 4; link++ ) @@ -237,26 +243,49 @@ void pci_setup(void) pci_writew(devfn, PCI_COMMAND, cmd); } - /* - * At the moment qemu-xen can't deal with relocated memory regions. - * It's too close to the release to make a proper fix; for now, - * only allow the MMIO hole to grow large enough to move guest memory - * if we're running qemu-traditional. Items that don't fit will be - * relocated into the 64-bit address space. - * - * This loop now does the following: - * - If allow_memory_relocate, increase the MMIO hole until it's - * big enough, or until it's 2GiB - * - If !allow_memory_relocate, increase the MMIO hole until it's - * big enough, or until it's 2GiB, or until it overlaps guest - * memory - */ - while ( (mmio_total > (pci_mem_end - pci_mem_start)) - && ((pci_mem_start << 1) != 0) - && (allow_memory_relocate - || (((pci_mem_start << 1) >> PAGE_SHIFT) - >= hvm_info->low_mem_pgend)) ) - pci_mem_start <<= 1; + if ( mmio_hole_size ) + { + uint64_t max_ram_below_4g = (1ULL << 32) - mmio_hole_size; + + if ( max_ram_below_4g > HVM_BELOW_4G_MMIO_START ) + { + printf("max_ram_below_4g=0x"PRIllx + " too big for mmio_hole_size=0x"PRIllx + " has been ignored.\n", + PRIllx_arg(max_ram_below_4g), + PRIllx_arg(mmio_hole_size)); + } + else + { + pci_mem_start = max_ram_below_4g; + printf("pci_mem_start=0x%lx (was 0x%x) for mmio_hole_size=%lu\n", + pci_mem_start, HVM_BELOW_4G_MMIO_START, + (long)mmio_hole_size); + } + } + else + { + /* + * At the moment qemu-xen can't deal with relocated memory regions. + * It's too close to the release to make a proper fix; for now, + * only allow the MMIO hole to grow large enough to move guest memory + * if we're running qemu-traditional. Items that don't fit will be + * relocated into the 64-bit address space. + * + * This loop now does the following: + * - If allow_memory_relocate, increase the MMIO hole until it's + * big enough, or until it's 2GiB + * - If !allow_memory_relocate, increase the MMIO hole until it's + * big enough, or until it's 2GiB, or until it overlaps guest + * memory + */ + while ( (mmio_total > (pci_mem_end - pci_mem_start)) + && ((pci_mem_start << 1) != 0) + && (allow_memory_relocate + || (((pci_mem_start << 1) >> PAGE_SHIFT) + >= hvm_info->low_mem_pgend)) ) + pci_mem_start <<= 1; + } if ( mmio_total > (pci_mem_end - pci_mem_start) ) { diff --git a/tools/libxl/libxl.h b/tools/libxl/libxl.h index 28b614fb93..c3451bdc42 100644 --- a/tools/libxl/libxl.h +++ b/tools/libxl/libxl.h @@ -157,6 +157,11 @@ #define LIBXL_HAVE_BUILDINFO_HVM_VIRIDIAN_ENABLE_DISABLE 1 #define LIBXL_BUILDINFO_HVM_VIRIDIAN_ENABLE_DISABLE_WIDTH 64 +/* + * libxl_domain_build_info has the u.hvm.mmio_hole_memkb field. + */ +#define LIBXL_HAVE_BUILDINFO_HVM_MMIO_HOLE_MEMKB 1 + /* * libxl ABI compatibility * diff --git a/tools/libxl/libxl_create.c b/tools/libxl/libxl_create.c index 4b33d07372..b1ff5aee7d 100644 --- a/tools/libxl/libxl_create.c +++ b/tools/libxl/libxl_create.c @@ -23,6 +23,7 @@ #include #include #include +#include int libxl__domain_create_info_setdefault(libxl__gc *gc, libxl_domain_create_info *c_info) @@ -226,6 +227,8 @@ int libxl__domain_build_info_setdefault(libxl__gc *gc, case LIBXL_DOMAIN_TYPE_HVM: if (b_info->shadow_memkb == LIBXL_MEMKB_DEFAULT) b_info->shadow_memkb = 0; + if (b_info->u.hvm.mmio_hole_memkb == LIBXL_MEMKB_DEFAULT) + b_info->u.hvm.mmio_hole_memkb = 0; if (!b_info->u.hvm.vga.kind) b_info->u.hvm.vga.kind = LIBXL_VGA_INTERFACE_TYPE_CIRRUS; @@ -429,13 +432,25 @@ int libxl__domain_build(libxl__gc *gc, vments[4] = "start_time"; vments[5] = libxl__sprintf(gc, "%lu.%02d", start_time.tv_sec,(int)start_time.tv_usec/10000); - localents = libxl__calloc(gc, 7, sizeof(char *)); - localents[0] = "platform/acpi"; - localents[1] = libxl_defbool_val(info->u.hvm.acpi) ? "1" : "0"; - localents[2] = "platform/acpi_s3"; - localents[3] = libxl_defbool_val(info->u.hvm.acpi_s3) ? "1" : "0"; - localents[4] = "platform/acpi_s4"; - localents[5] = libxl_defbool_val(info->u.hvm.acpi_s4) ? "1" : "0"; + localents = libxl__calloc(gc, 9, sizeof(char *)); + i = 0; + localents[i++] = "platform/acpi"; + localents[i++] = libxl_defbool_val(info->u.hvm.acpi) ? "1" : "0"; + localents[i++] = "platform/acpi_s3"; + localents[i++] = libxl_defbool_val(info->u.hvm.acpi_s3) ? "1" : "0"; + localents[i++] = "platform/acpi_s4"; + localents[i++] = libxl_defbool_val(info->u.hvm.acpi_s4) ? "1" : "0"; + if (info->u.hvm.mmio_hole_memkb) { + uint64_t max_ram_below_4g = + (1ULL << 32) - (info->u.hvm.mmio_hole_memkb << 10); + + if (max_ram_below_4g <= HVM_BELOW_4G_MMIO_START) { + localents[i++] = "platform/mmio_hole_size"; + localents[i++] = + libxl__sprintf(gc, "%"PRIu64, + info->u.hvm.mmio_hole_memkb << 10); + } + } break; case LIBXL_DOMAIN_TYPE_PV: diff --git a/tools/libxl/libxl_dm.c b/tools/libxl/libxl_dm.c index 14dc9fa426..3e191c3b26 100644 --- a/tools/libxl/libxl_dm.c +++ b/tools/libxl/libxl_dm.c @@ -18,6 +18,7 @@ #include "libxl_osdeps.h" /* must come before any other headers */ #include "libxl_internal.h" +#include static const char *libxl_tapif_script(libxl__gc *gc) { @@ -416,6 +417,7 @@ static char ** libxl__build_device_model_args_new(libxl__gc *gc, const libxl_vnc_info *vnc = libxl__dm_vnc(guest_config); const libxl_sdl_info *sdl = dm_sdl(guest_config); const char *keymap = dm_keymap(guest_config); + char *machinearg; flexarray_t *dm_args; int i, connection, devid; uint64_t ram_size; @@ -720,10 +722,24 @@ static char ** libxl__build_device_model_args_new(libxl__gc *gc, /* Switching here to the machine "pc" which does not add * the xen-platform device instead of the default "xenfv" machine. */ - flexarray_append(dm_args, "pc,accel=xen"); + machinearg = libxl__sprintf(gc, "pc,accel=xen"); } else { - flexarray_append(dm_args, "xenfv"); + machinearg = libxl__sprintf(gc, "xenfv"); } + if (b_info->u.hvm.mmio_hole_memkb) { + uint64_t max_ram_below_4g = (1ULL << 32) - + (b_info->u.hvm.mmio_hole_memkb << 10); + + if (max_ram_below_4g > HVM_BELOW_4G_MMIO_START) { + LOG(WARN, "mmio_hole_memkb=%"PRIu64 + " invalid ignored.\n", + b_info->u.hvm.mmio_hole_memkb); + } else { + machinearg = libxl__sprintf(gc, "%s,max-ram-below-4g=%"PRIu64, + machinearg, max_ram_below_4g); + } + } + flexarray_append(dm_args, machinearg); for (i = 0; b_info->extra_hvm && b_info->extra_hvm[i] != NULL; i++) flexarray_append(dm_args, b_info->extra_hvm[i]); break; diff --git a/tools/libxl/libxl_dom.c b/tools/libxl/libxl_dom.c index 9d830e11bd..74ea84b74a 100644 --- a/tools/libxl/libxl_dom.c +++ b/tools/libxl/libxl_dom.c @@ -23,6 +23,7 @@ #include #include #include +#include libxl_domain_type libxl__domain_type(libxl__gc *gc, uint32_t domid) { @@ -800,6 +801,13 @@ int libxl__build_hvm(libxl__gc *gc, uint32_t domid, args.mem_size = (uint64_t)(info->max_memkb - info->video_memkb) << 10; args.mem_target = (uint64_t)(info->target_memkb - info->video_memkb) << 10; args.claim_enabled = libxl_defbool_val(info->claim_mode); + if (info->u.hvm.mmio_hole_memkb) { + uint64_t max_ram_below_4g = (1ULL << 32) - + (info->u.hvm.mmio_hole_memkb << 10); + + if (max_ram_below_4g < HVM_BELOW_4G_MMIO_START) + args.mmio_size = info->u.hvm.mmio_hole_memkb << 10; + } if (libxl__domain_firmware(gc, info, &args)) { LOG(ERROR, "initializing domain firmware failed"); goto out; diff --git a/tools/libxl/libxl_types.idl b/tools/libxl/libxl_types.idl index fdda7618fd..ca3f72479d 100644 --- a/tools/libxl/libxl_types.idl +++ b/tools/libxl/libxl_types.idl @@ -413,6 +413,7 @@ libxl_domain_build_info = Struct("domain_build_info",[ ("timeoffset", string), ("hpet", libxl_defbool), ("vpt_align", libxl_defbool), + ("mmio_hole_memkb", MemKB), ("timer_mode", libxl_timer_mode), ("nested_hvm", libxl_defbool), ("smbios_firmware", string), diff --git a/tools/libxl/xl_cmdimpl.c b/tools/libxl/xl_cmdimpl.c index 0882644392..3c9f14686f 100644 --- a/tools/libxl/xl_cmdimpl.c +++ b/tools/libxl/xl_cmdimpl.c @@ -34,6 +34,7 @@ #include #include #include +#include #include "libxl.h" #include "libxl_utils.h" @@ -1191,6 +1192,18 @@ static void parse_config_data(const char *config_source, exit(-ERROR_FAIL); } + if (!xlu_cfg_get_long(config, "mmio_hole", &l, 0)) { + uint64_t mmio_hole_size; + + b_info->u.hvm.mmio_hole_memkb = l * 1024; + mmio_hole_size = b_info->u.hvm.mmio_hole_memkb * 1024; + if (mmio_hole_size < HVM_BELOW_4G_MMIO_LENGTH || + mmio_hole_size > HVM_BELOW_4G_MMIO_START) { + fprintf(stderr, + "ERROR: invalid value %ld for \"mmio_hole\"\n", l); + exit (1); + } + } if (!xlu_cfg_get_long(config, "timer_mode", &l, 1)) { const char *s = libxl_timer_mode_to_string(l); fprintf(stderr, "WARNING: specifying \"timer_mode\" as an integer is deprecated. "