mirror of
https://github.com/Motorhead1991/qemu.git
synced 2025-12-25 08:58:36 -07:00
Support DMA read/write draining should be easy for existing VT-d
emulation since the emulation itself does not have any request queue
there so we don't need to do anything to flush the un-commited queue.
What we need to do is to declare the support.
These capabilities are required to pass Windows SVVP test program. It
is verified that when with parameters "x-aw-bits=48,caching-mode=off"
we can pass the Windows SVVP test with this patch applied. Otherwise
we'll fail with:
IOMMU[0] - DWD (DMA write draining) not supported
IOMMU[0] - DWD (DMA read draining) not supported
Segment 0 has no DMA remapping capable IOMMU units
However since these bits are not declared support for QEMU<=3.1, we'll
need a compatibility bit for it and we turn this on by default only
for QEMU>=4.0.
Please refer to VT-d spec 6.5.4 for more information.
CC: Yu Wang <wyu@redhat.com>
Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1654550
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
|
||
|---|---|---|
| .. | ||
| block | ||
| chardev | ||
| crypto | ||
| disas | ||
| exec | ||
| fpu | ||
| hw | ||
| io | ||
| libdecnumber | ||
| migration | ||
| monitor | ||
| net | ||
| qapi | ||
| qemu | ||
| qom | ||
| scsi | ||
| standard-headers | ||
| sysemu | ||
| ui | ||
| elf.h | ||
| glib-compat.h | ||
| qemu-common.h | ||
| qemu-io.h | ||
| trace-tcg.h | ||