@@ -782,7 +782,11 @@ static PCIDevice *do_pci_register_device(PCIDevice *pci_dev, PCIBus *bus,
/* FIXME: Make dma_context_fn use MemoryRegions instead, so this path is
* taken unconditionally */
/* FIXME: inherit memory region from bus creator */
- address_space_init(&pci_dev->bus_master_as, get_system_memory());
+ memory_region_init_alias(&pci_dev->bus_master_enable_region, "bus master",
+ get_system_memory(), 0,
+ memory_region_size(get_system_memory()));
+ memory_region_set_enabled(&pci_dev->bus_master_enable_region, false);
+ address_space_init(&pci_dev->bus_master_as, &pci_dev->bus_master_enable_region);
pci_dev->dma = g_new(DMAContext, 1);
dma_context_init(pci_dev->dma, &pci_dev->bus_master_as, NULL, NULL, NULL);
}
@@ -841,6 +845,7 @@ static void do_pci_unregister_device(PCIDevice *pci_dev)
if (!pci_dev->bus->dma_context_fn) {
address_space_destroy(&pci_dev->bus_master_as);
+ memory_region_destroy(&pci_dev->bus_master_enable_region);
g_free(pci_dev->dma);
pci_dev->dma = NULL;
}
@@ -1065,8 +1070,12 @@ void pci_default_write_config(PCIDevice *d, uint32_t addr, uint32_t val, int l)
range_covers_byte(addr, l, PCI_COMMAND))
pci_update_mappings(d);
- if (range_covers_byte(addr, l, PCI_COMMAND))
+ if (range_covers_byte(addr, l, PCI_COMMAND)) {
pci_update_irq_disabled(d, was_irq_disabled);
+ memory_region_set_enabled(&d->bus_master_enable_region,
+ pci_get_word(d->config + PCI_COMMAND)
+ & PCI_COMMAND_MASTER);
+ }
msi_write_config(d, addr, val, l);
msix_write_config(d, addr, val, l);
@@ -212,6 +212,7 @@ struct PCIDevice {
char name[64];
PCIIORegion io_regions[PCI_NUM_REGIONS];
AddressSpace bus_master_as;
+ MemoryRegion bus_master_enable_region;
DMAContext *dma;
/* do not access the following fields */
Currently we ignore PCI_COMMAND_MASTER completely: DMA succeeds even when the bit is clear. Honor PCI_COMMAND_MASTER by inserting a memory region into the device's bus master address space, and tying its enable status to PCI_COMMAND_MASTER. Tested using setpci -s 03 COMMAND=3 while a ping was running on a NIC in slot 3. The kernel (Linux) detected the stall and recovered after the command setpci -s 03 COMMAND=7 was issued. Signed-off-by: Avi Kivity <avi@redhat.com> --- hw/pci.c | 13 +++++++++++-- hw/pci.h | 1 + 2 files changed, 12 insertions(+), 2 deletions(-)