From 08b1df8ff463e72b0875538fb991d5393047606c Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Wed, 3 Feb 2021 14:18:28 +0100 Subject: pci: add romsize property This property can be useful for distros to set up known-good ROM sizes for migration purposes. The VM will fail to start if the ROM is too large, and migration compatibility will not be broken if the ROM is too small. Note that even though romsize is a uint32_t, it has to be between 1 (because empty ROM files are not accepted, and romsize must be greater than the file) and 2^31 (because values above are not powers of two and are rejected). Signed-off-by: Paolo Bonzini Reviewed-by: Dr. David Alan Gilbert Reviewed-by: Peter Xu Message-Id: <20201218182736.1634344-1-pbonzini@redhat.com> Signed-off-by: Paolo Bonzini Message-Id: <20210203131828.156467-3-pbonzini@redhat.com> Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin Reviewed-by: David Edmondson Acked-by: Laszlo Ersek --- hw/pci/pci.c | 19 +++++++++++++++++-- 1 file changed, 17 insertions(+), 2 deletions(-) (limited to 'hw/pci/pci.c') diff --git a/hw/pci/pci.c b/hw/pci/pci.c index 58560c0..a9ebef8 100644 --- a/hw/pci/pci.c +++ b/hw/pci/pci.c @@ -69,6 +69,7 @@ static void pcibus_reset(BusState *qbus); static Property pci_props[] = { DEFINE_PROP_PCI_DEVFN("addr", PCIDevice, devfn, -1), DEFINE_PROP_STRING("romfile", PCIDevice, romfile), + DEFINE_PROP_UINT32("romsize", PCIDevice, romsize, -1), DEFINE_PROP_UINT32("rombar", PCIDevice, rom_bar, 1), DEFINE_PROP_BIT("multifunction", PCIDevice, cap_present, QEMU_PCI_CAP_MULTIFUNCTION_BITNR, false), @@ -2084,6 +2085,11 @@ static void pci_qdev_realize(DeviceState *qdev, Error **errp) bool is_default_rom; uint16_t class_id; + if (pci_dev->romsize != -1 && !is_power_of_2(pci_dev->romsize)) { + error_setg(errp, "ROM size %u is not a power of two", pci_dev->romsize); + return; + } + /* initialize cap_present for pci_is_express() and pci_config_size(), * Note that hybrid PCIs are not set automatically and need to manage * QEMU_PCI_CAP_EXPRESS manually */ @@ -2349,7 +2355,16 @@ static void pci_add_option_rom(PCIDevice *pdev, bool is_default_rom, g_free(path); return; } - size = pow2ceil(size); + if (pdev->romsize != -1) { + if (size > pdev->romsize) { + error_setg(errp, "romfile \"%s\" (%u bytes) is too large for ROM size %u", + pdev->romfile, (uint32_t)size, pdev->romsize); + g_free(path); + return; + } + } else { + pdev->romsize = pow2ceil(size); + } vmsd = qdev_get_vmsd(DEVICE(pdev)); @@ -2359,7 +2374,7 @@ static void pci_add_option_rom(PCIDevice *pdev, bool is_default_rom, snprintf(name, sizeof(name), "%s.rom", object_get_typename(OBJECT(pdev))); } pdev->has_rom = true; - memory_region_init_rom(&pdev->rom, OBJECT(pdev), name, size, &error_fatal); + memory_region_init_rom(&pdev->rom, OBJECT(pdev), name, pdev->romsize, &error_fatal); ptr = memory_region_get_ram_ptr(&pdev->rom); if (load_image_size(path, ptr, size) < 0) { error_setg(errp, "failed to load romfile \"%s\"", pdev->romfile); -- cgit v1.1