From c8389550dedc65892fba9c3df29423efd802f544 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Marc-Andr=C3=A9=20Lureau?= Date: Mon, 7 Aug 2017 18:45:13 +0200 Subject: [PATCH] vmgenid: replace x-write-pointer-available hack MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This compat property sole function is to prevent the device from being instantiated. Instead of requiring an extra compat property, check if fw_cfg has DMA enabled. fw_cfg is a built-in device that is initialized very early by the machine init code. We have at least one other device that also assumes fw_cfg_find() can be safely used on realize: pvpanic. This has the additional benefit of handling other cases properly, like: $ qemu-system-x86_64 -device vmgenid -machine none qemu-system-x86_64: -device vmgenid: vmgenid requires DMA write support in fw_cfg, which this machine type does not provide $ qemu-system-x86_64 -device vmgenid -machine pc-i440fx-2.9 -global fw_cfg.dma_enabled=off qemu-system-x86_64: -device vmgenid: vmgenid requires DMA write support in fw_cfg, which this machine type does not provide $ qemu-system-x86_64 -device vmgenid -machine pc-i440fx-2.6 -global fw_cfg.dma_enabled=on [boots normally] Suggested-by: Eduardo Habkost Signed-off-by: Marc-André Lureau Reviewed-by: Michael S. Tsirkin Reviewed-by: Eduardo Habkost Reviewed-by: Ben Warren Reviewed-by: Laszlo Ersek Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin --- hw/acpi/bios-linker-loader.c | 10 ++++++++++ hw/acpi/vmgenid.c | 9 +-------- include/hw/acpi/bios-linker-loader.h | 2 ++ include/hw/acpi/vmgenid.h | 1 - include/hw/compat.h | 4 ---- 5 files changed, 13 insertions(+), 13 deletions(-) diff --git a/hw/acpi/bios-linker-loader.c b/hw/acpi/bios-linker-loader.c index 046183a0f1..d16b8bbcb1 100644 --- a/hw/acpi/bios-linker-loader.c +++ b/hw/acpi/bios-linker-loader.c @@ -168,6 +168,16 @@ bios_linker_find_file(const BIOSLinker *linker, const char *name) return NULL; } +/* + * board code must realize fw_cfg first, as a fixed device, before + * another device realize function call bios_linker_loader_can_write_pointer() + */ +bool bios_linker_loader_can_write_pointer(void) +{ + FWCfgState *fw_cfg = fw_cfg_find(); + return fw_cfg && fw_cfg_dma_enabled(fw_cfg); +} + /* * bios_linker_loader_alloc: ask guest to load file into guest memory. * diff --git a/hw/acpi/vmgenid.c b/hw/acpi/vmgenid.c index 876723a4ce..2876d8a639 100644 --- a/hw/acpi/vmgenid.c +++ b/hw/acpi/vmgenid.c @@ -205,17 +205,11 @@ static void vmgenid_handle_reset(void *opaque) memset(vms->vmgenid_addr_le, 0, ARRAY_SIZE(vms->vmgenid_addr_le)); } -static Property vmgenid_properties[] = { - DEFINE_PROP_BOOL("x-write-pointer-available", VmGenIdState, - write_pointer_available, true), - DEFINE_PROP_END_OF_LIST(), -}; - static void vmgenid_realize(DeviceState *dev, Error **errp) { VmGenIdState *vms = VMGENID(dev); - if (!vms->write_pointer_available) { + if (!bios_linker_loader_can_write_pointer()) { error_setg(errp, "%s requires DMA write support in fw_cfg, " "which this machine type does not provide", VMGENID_DEVICE); return; @@ -239,7 +233,6 @@ static void vmgenid_device_class_init(ObjectClass *klass, void *data) dc->vmsd = &vmstate_vmgenid; dc->realize = vmgenid_realize; dc->hotpluggable = false; - dc->props = vmgenid_properties; set_bit(DEVICE_CATEGORY_MISC, dc->categories); object_class_property_add_str(klass, VMGENID_GUID, NULL, diff --git a/include/hw/acpi/bios-linker-loader.h b/include/hw/acpi/bios-linker-loader.h index efe17b0b9c..a711dbced8 100644 --- a/include/hw/acpi/bios-linker-loader.h +++ b/include/hw/acpi/bios-linker-loader.h @@ -7,6 +7,8 @@ typedef struct BIOSLinker { GArray *file_list; } BIOSLinker; +bool bios_linker_loader_can_write_pointer(void); + BIOSLinker *bios_linker_loader_init(void); void bios_linker_loader_alloc(BIOSLinker *linker, diff --git a/include/hw/acpi/vmgenid.h b/include/hw/acpi/vmgenid.h index 7beb9592fb..38586ecbdf 100644 --- a/include/hw/acpi/vmgenid.h +++ b/include/hw/acpi/vmgenid.h @@ -21,7 +21,6 @@ typedef struct VmGenIdState { DeviceClass parent_obj; QemuUUID guid; /* The 128-bit GUID seen by the guest */ uint8_t vmgenid_addr_le[8]; /* Address of the GUID (little-endian) */ - bool write_pointer_available; } VmGenIdState; /* returns NULL unless there is exactly one device */ diff --git a/include/hw/compat.h b/include/hw/compat.h index 3e101f8f67..9cc14dd798 100644 --- a/include/hw/compat.h +++ b/include/hw/compat.h @@ -153,10 +153,6 @@ .driver = "fw_cfg_io",\ .property = "dma_enabled",\ .value = "off",\ - },{\ - .driver = "vmgenid",\ - .property = "x-write-pointer-available",\ - .value = "off",\ }, #define HW_COMPAT_2_3 \