From 7df32ca08ad0afdac623e43a99984c26177468f0 Mon Sep 17 00:00:00 2001 From: "Michael S. Tsirkin" Date: Sun, 4 Sep 2011 16:50:55 +0300 Subject: pci: implement bridge filtering Support bridge filtering on top of the memory API as suggested by Avi Kivity: Create a memory region for the bridge's address space. This region is not directly added to system_memory or its descendants. Devices under the bridge see this region as its pci_address_space(). The region is as large as the entire address space - it does not take into account any windows. For each of the three windows (pref, non-pref, vga), create an alias with the appropriate start and size. Map the alias into the bridge's parent's pci_address_space(), as subregions. Signed-off-by: Michael S. Tsirkin --- hw/pci_bridge.c | 92 +++++++++++++++++++++++++++++++++++++++++++++++++++++---- 1 file changed, 86 insertions(+), 6 deletions(-) (limited to 'hw/pci_bridge.c') diff --git a/hw/pci_bridge.c b/hw/pci_bridge.c index e0b339edb0..25e9b7c227 100644 --- a/hw/pci_bridge.c +++ b/hw/pci_bridge.c @@ -135,6 +135,77 @@ pcibus_t pci_bridge_get_limit(const PCIDevice *bridge, uint8_t type) return limit; } +static void pci_bridge_init_alias(PCIBridge *bridge, MemoryRegion *alias, + uint8_t type, const char *name, + MemoryRegion *space, + MemoryRegion *parent_space, + bool enabled) +{ + pcibus_t base = pci_bridge_get_base(&bridge->dev, type); + pcibus_t limit = pci_bridge_get_limit(&bridge->dev, type); + /* TODO: this doesn't handle base = 0 limit = 2^64 - 1 correctly. + * Apparently no way to do this with existing memory APIs. */ + pcibus_t size = enabled && limit >= base ? limit + 1 - base : 0; + + memory_region_init_alias(alias, name, space, base, size); + memory_region_add_subregion_overlap(parent_space, base, alias, 1); +} + +static void pci_bridge_cleanup_alias(MemoryRegion *alias, + MemoryRegion *parent_space) +{ + memory_region_del_subregion(parent_space, alias); + memory_region_destroy(alias); +} + +static void pci_bridge_region_init(PCIBridge *br) +{ + PCIBus *sec_bus = &br->sec_bus; + PCIBus *parent = br->dev.bus; + uint16_t cmd = pci_get_word(br->dev.config + PCI_COMMAND); + + pci_bridge_init_alias(br, &br->alias_pref_mem, + PCI_BASE_ADDRESS_MEM_PREFETCH, + "pci_bridge_pref_mem", + sec_bus->address_space_mem, + parent->address_space_mem, + cmd & PCI_COMMAND_MEMORY); + pci_bridge_init_alias(br, &br->alias_mem, + PCI_BASE_ADDRESS_SPACE_MEMORY, + "pci_bridge_mem", + sec_bus->address_space_mem, + parent->address_space_mem, + cmd & PCI_COMMAND_MEMORY); + pci_bridge_init_alias(br, &br->alias_io, + PCI_BASE_ADDRESS_SPACE_IO, + "pci_bridge_io", + sec_bus->address_space_io, + parent->address_space_io, + cmd & PCI_COMMAND_IO); + /* TODO: optinal VGA and VGA palette snooping support. */ +} + +static void pci_bridge_region_cleanup(PCIBridge *br) +{ + PCIBus *parent = br->dev.bus; + pci_bridge_cleanup_alias(&br->alias_io, + parent->address_space_io); + pci_bridge_cleanup_alias(&br->alias_mem, + parent->address_space_mem); + pci_bridge_cleanup_alias(&br->alias_pref_mem, + parent->address_space_mem); +} + +static void pci_bridge_update_mappings(PCIBridge *br) +{ + /* Make updates atomic to: handle the case of one VCPU updating the bridge + * while another accesses an unaffected region. */ + memory_region_transaction_begin(); + pci_bridge_region_cleanup(br); + pci_bridge_region_init(br); + memory_region_transaction_commit(); +} + /* default write_config function for PCI-to-PCI bridge */ void pci_bridge_write_config(PCIDevice *d, uint32_t address, uint32_t val, int len) @@ -145,13 +216,15 @@ void pci_bridge_write_config(PCIDevice *d, pci_default_write_config(d, address, val, len); - if (/* io base/limit */ + if (ranges_overlap(address, len, PCI_COMMAND, 2) || + + /* io base/limit */ ranges_overlap(address, len, PCI_IO_BASE, 2) || /* memory base/limit, prefetchable base/limit and io base/limit upper 16 */ ranges_overlap(address, len, PCI_MEMORY_BASE, 20)) { - pci_bridge_update_mappings(&s->sec_bus); + pci_bridge_update_mappings(s); } newctl = pci_get_word(d->config + PCI_BRIDGE_CONTROL); @@ -246,10 +319,11 @@ int pci_bridge_initfn(PCIDevice *dev) br->bus_name); sec_bus->parent_dev = dev; sec_bus->map_irq = br->map_irq; - /* TODO: use memory API to perform memory filtering. */ - sec_bus->address_space_mem = parent->address_space_mem; - sec_bus->address_space_io = parent->address_space_io; - + sec_bus->address_space_mem = g_new(MemoryRegion, 1); + memory_region_init(sec_bus->address_space_mem, "pci_pridge_pci", INT64_MAX); + sec_bus->address_space_io = g_new(MemoryRegion, 1); + memory_region_init(sec_bus->address_space_io, "pci_bridge_io", 65536); + pci_bridge_region_init(br); QLIST_INIT(&sec_bus->child); QLIST_INSERT_HEAD(&parent->child, sec_bus, sibling); return 0; @@ -259,8 +333,14 @@ int pci_bridge_initfn(PCIDevice *dev) int pci_bridge_exitfn(PCIDevice *pci_dev) { PCIBridge *s = DO_UPCAST(PCIBridge, dev, pci_dev); + PCIBus *sec_bus = &s->sec_bus; assert(QLIST_EMPTY(&s->sec_bus.child)); QLIST_REMOVE(&s->sec_bus, sibling); + pci_bridge_region_cleanup(s); + memory_region_destroy(sec_bus->address_space_mem); + g_free(sec_bus->address_space_mem); + memory_region_destroy(sec_bus->address_space_io); + g_free(sec_bus->address_space_io); /* qbus_free() is called automatically by qdev_free() */ return 0; } -- cgit v1.2.3