When supported by the host kernel, we can use read/write on the
PCI sysfs resource file for I/O port regions. This allows us to
avoid raw in/out commands and works with deprivileged guests via
libvirt. For uid 0 callers, we use in/out directly to avoid any
compatibility issues.
Signed-off-by: Alex Williamson
---
Required kernel patch pending here:
http://www.spinics.net/lists/linux-pci/msg09389.html
hw/device-assignment.c | 131
hw/device-assignment.h |1
2 files changed, 99 insertions(+), 33 deletions(-)
diff --git a/hw/device-assignment.c b/hw/device-assignment.c
index 2bba22f..37c1278 100644
--- a/hw/device-assignment.c
+++ b/hw/device-assignment.c
@@ -67,6 +67,28 @@ static uint32_t guest_to_host_ioport(AssignedDevRegion
*region, uint32_t addr)
return region->u.r_baseport + (addr - region->e_physbase);
}
+static int assigned_dev_ioport_rw(AssignedDevRegion *dev_region,
+ uint32_t addr, int len, uint32_t *val,
+ int write)
+{
+if (dev_region->region->resource_fd == -1)
+return -1;
+
+if (write) {
+if (pwrite(dev_region->region->resource_fd, val, len,
+ (addr - dev_region->e_physbase)) != len) {
+return -1;
+}
+} else {
+if (pread(dev_region->region->resource_fd, val, len,
+ (addr - dev_region->e_physbase)) != len) {
+return -1;
+}
+}
+
+return 0;
+}
+
static void assigned_dev_ioport_writeb(void *opaque, uint32_t addr,
uint32_t value)
{
@@ -77,7 +99,9 @@ static void assigned_dev_ioport_writeb(void *opaque, uint32_t
addr,
r_pio, (int)r_access->e_physbase,
(unsigned long)r_access->u.r_baseport, value);
-outb(value, r_pio);
+if (assigned_dev_ioport_rw(r_access, addr, 1, &value, 1) != 0) {
+outb(value, r_pio);
+}
}
static void assigned_dev_ioport_writew(void *opaque, uint32_t addr,
@@ -90,7 +114,9 @@ static void assigned_dev_ioport_writew(void *opaque,
uint32_t addr,
r_pio, (int)r_access->e_physbase,
(unsigned long)r_access->u.r_baseport, value);
-outw(value, r_pio);
+if (assigned_dev_ioport_rw(r_access, addr, 2, &value, 1) != 0) {
+outw(value, r_pio);
+}
}
static void assigned_dev_ioport_writel(void *opaque, uint32_t addr,
@@ -103,7 +129,9 @@ static void assigned_dev_ioport_writel(void *opaque,
uint32_t addr,
r_pio, (int)r_access->e_physbase,
(unsigned long)r_access->u.r_baseport, value);
-outl(value, r_pio);
+if (assigned_dev_ioport_rw(r_access, addr, 4, &value, 1) != 0) {
+outl(value, r_pio);
+}
}
static uint32_t assigned_dev_ioport_readb(void *opaque, uint32_t addr)
@@ -112,7 +140,9 @@ static uint32_t assigned_dev_ioport_readb(void *opaque,
uint32_t addr)
uint32_t r_pio = guest_to_host_ioport(r_access, addr);
uint32_t value;
-value = inb(r_pio);
+if (assigned_dev_ioport_rw(r_access, addr, 1, &value, 0) != 0) {
+value = inb(r_pio);
+}
DEBUG("r_pio=%08x e_physbase=%08x r_=%08lx value=%08x\n",
r_pio, (int)r_access->e_physbase,
@@ -127,7 +157,9 @@ static uint32_t assigned_dev_ioport_readw(void *opaque,
uint32_t addr)
uint32_t r_pio = guest_to_host_ioport(r_access, addr);
uint32_t value;
-value = inw(r_pio);
+if (assigned_dev_ioport_rw(r_access, addr, 2, &value, 0) != 0) {
+value = inw(r_pio);
+}
DEBUG("r_pio=%08x e_physbase=%08x r_baseport=%08lx value=%08x\n",
r_pio, (int)r_access->e_physbase,
@@ -142,7 +174,9 @@ static uint32_t assigned_dev_ioport_readl(void *opaque,
uint32_t addr)
uint32_t r_pio = guest_to_host_ioport(r_access, addr);
uint32_t value;
-value = inl(r_pio);
+if (assigned_dev_ioport_rw(r_access, addr, 4, &value, 0) != 0) {
+value = inl(r_pio);
+}
DEBUG("r_pio=%08x e_physbase=%08x r_baseport=%08lx value=%08x\n",
r_pio, (int)r_access->e_physbase,
@@ -305,7 +339,7 @@ static void assigned_dev_ioport_map(PCIDevice *pci_dev, int
region_num,
DEBUG("e_phys=0x%" FMT_PCIBUS " r_baseport=%x type=0x%x len=%" FMT_PCIBUS
" region_num=%d \n",
addr, region->u.r_baseport, type, size, region_num);
-if (first_map) {
+if (first_map && region->region->resource_fd < 0) {
struct ioperm_data *data;
data = qemu_mallocz(sizeof(struct ioperm_data));
@@ -586,19 +620,46 @@ static int assigned_dev_register_regions(PCIRegion
*io_regions,
slow_map ? assigned_dev_iomem_map_slow
: assigned_dev_iomem_map);
continue;
+} else {
+/* handle port io regions */
+uint32_t val;
+int ret;
+
+/* Test kernel support for ioport resource read/write. Old
+ * kerne
