memory: Provide separate handling of unassigned io ports accesses

Accesses to unassigned io ports shall return -1 on read and be ignored
on write. Ensure these properties via dedicated ops, decoupling us from
the memory core's handling of unassigned accesses.

Cc: qemu-stable@nongnu.org
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Jan Kiszka 2013-09-02 18:43:30 +02:00 committed by Paolo Bonzini
parent 8826624970
commit 3bb28b7208
3 changed files with 22 additions and 1 deletions

3
exec.c
View file

@ -1805,7 +1805,8 @@ static void memory_map_init(void)
address_space_init(&address_space_memory, system_memory, "memory");
system_io = g_malloc(sizeof(*system_io));
memory_region_init(system_io, NULL, "io", 65536);
memory_region_init_io(system_io, NULL, &unassigned_io_ops, NULL, "io",
65536);
address_space_init(&address_space_io, system_io, "I/O");
memory_listener_register(&core_memory_listener, &address_space_memory);

View file

@ -45,6 +45,10 @@ typedef struct MemoryRegionPortio {
#define PORTIO_END_OF_LIST() { }
#ifndef CONFIG_USER_ONLY
extern const MemoryRegionOps unassigned_io_ops;
#endif
void cpu_outb(pio_addr_t addr, uint8_t val);
void cpu_outw(pio_addr_t addr, uint16_t val);
void cpu_outl(pio_addr_t addr, uint32_t val);

View file

@ -44,6 +44,22 @@ typedef struct MemoryRegionPortioList {
MemoryRegionPortio ports[];
} MemoryRegionPortioList;
static uint64_t unassigned_io_read(void *opaque, hwaddr addr, unsigned size)
{
return -1ULL;
}
static void unassigned_io_write(void *opaque, hwaddr addr, uint64_t val,
unsigned size)
{
}
const MemoryRegionOps unassigned_io_ops = {
.read = unassigned_io_read,
.write = unassigned_io_write,
.endianness = DEVICE_NATIVE_ENDIAN,
};
void cpu_outb(pio_addr_t addr, uint8_t val)
{
LOG_IOPORT("outb: %04"FMT_pioaddr" %02"PRIx8"\n", addr, val);