intel-iommu: add Intel IOMMU emulation to q35 and add a machine option "iommu" as a switch

Add Intel IOMMU emulation to q35 chipset and expose it to the guest.
1. Add a machine option. Users can use "-machine iommu=on|off" in the command
line to enable/disable Intel IOMMU. The default is off.
2. Accroding to the machine option, q35 will initialize the Intel IOMMU and
use pci_setup_iommu() to setup q35_host_dma_iommu() as the IOMMU function for
the pci bus.
3. q35_host_dma_iommu() will return different address space according to the
bus_num and devfn of the device.

Signed-off-by: Le Tan <tamlokveer@gmail.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/include/hw/boards.h b/include/hw/boards.h
index 605a970934..dfb6718dc1 100644
--- a/include/hw/boards.h
+++ b/include/hw/boards.h
@@ -123,6 +123,7 @@ struct MachineState {
     bool mem_merge;
     bool usb;
     char *firmware;
+    bool iommu;
 
     ram_addr_t ram_size;
     ram_addr_t maxram_size;