On 05/14/2016 08:26 AM, Alex Williamson wrote:
On Wed, 4 May 2016 16:52:30 +1000
Alexey Kardashevskiy <a...@ozlabs.ru> wrote:
New VFIO_SPAPR_TCE_v2_IOMMU type supports dynamic DMA window management.
This adds ability to VFIO common code to dynamically allocate/remove
DMA windows in the host kernel when new VFIO container is added/removed.
This adds VFIO_IOMMU_SPAPR_TCE_CREATE ioctl to vfio_listener_region_add
and adds just created IOMMU into the host IOMMU list; the opposite
action is taken in vfio_listener_region_del.
When creating a new window, this uses heuristic to decide on the TCE table
levels number.
This should cause no guest visible change in behavior.
Signed-off-by: Alexey Kardashevskiy <a...@ozlabs.ru>
---
Changes:
v16:
* used memory_region_iommu_get_page_sizes() in vfio_listener_region_add()
* enforced no intersections between windows
v14:
* new to the series
---
hw/vfio/common.c | 133 ++++++++++++++++++++++++++++++++++++++++++++++++++-----
trace-events | 2 +
2 files changed, 125 insertions(+), 10 deletions(-)
diff --git a/hw/vfio/common.c b/hw/vfio/common.c
index 03daf88..bd2dee8 100644
--- a/hw/vfio/common.c
+++ b/hw/vfio/common.c
@@ -240,6 +240,18 @@ static int vfio_dma_map(VFIOContainer *container, hwaddr
iova,
return -errno;
}
+static bool range_contains(hwaddr start, hwaddr end, hwaddr addr)
+{
+ return start <= addr && addr <= end;
+}
a) If you want a "range_foo" function then put it in range.h
b) I suspect there are already range.h functions that can do this.
+
+static bool vfio_host_win_intersects(VFIOHostDMAWindow *hostwin,
+ hwaddr min_iova, hwaddr max_iova)
+{
+ return range_contains(hostwin->min_iova, hostwin->min_iova, min_iova) ||
+ range_contains(min_iova, max_iova, hostwin->min_iova);
+}
How is this different than ranges_overlap()?
+
static VFIOHostDMAWindow *vfio_host_win_lookup(VFIOContainer *container,
hwaddr min_iova, hwaddr
max_iova)
{
@@ -279,6 +291,14 @@ static int vfio_host_win_add(VFIOContainer *container,
return 0;
}
+static void vfio_host_win_del(VFIOContainer *container, hwaddr min_iova)
+{
+ VFIOHostDMAWindow *hostwin = vfio_host_win_lookup(container, min_iova, 1);
+
+ g_assert(hostwin);
Handle the error please.
Will this be enough?
if (!hostwin) {
error_report("%s: Cannot delete missing window at %"HWADDR_PRIx,
__func__, min_iova);
return;
}
+ QLIST_REMOVE(hostwin, hostwin_next);
+}
+
static bool vfio_listener_skipped_section(MemoryRegionSection *section)
{
return (!memory_region_is_ram(section->mr) &&
@@ -392,6 +412,69 @@ static void vfio_listener_region_add(MemoryListener
*listener,
}
end = int128_get64(int128_sub(llend, int128_one()));
+ if (container->iommu_type == VFIO_SPAPR_TCE_v2_IOMMU) {
+ VFIOHostDMAWindow *hostwin;
+ unsigned pagesizes = memory_region_iommu_get_page_sizes(section->mr);
+ unsigned pagesize = (hwaddr)1 << ctz64(pagesizes);
+ unsigned entries, pages;
+ struct vfio_iommu_spapr_tce_create create = { .argsz = sizeof(create)
};
+
+ trace_vfio_listener_region_add_iommu(iova, end);
+ /*
+ * FIXME: For VFIO iommu types which have KVM acceleration to
+ * avoid bouncing all map/unmaps through qemu this way, this
+ * would be the right place to wire that up (tell the KVM
+ * device emulation the VFIO iommu handles to use).
+ */
+ create.window_size = int128_get64(section->size);
+ create.page_shift = ctz64(pagesize);
+ /*
+ * SPAPR host supports multilevel TCE tables, there is some
+ * heuristic to decide how many levels we want for our table:
+ * 0..64 = 1; 65..4096 = 2; 4097..262144 = 3; 262145.. = 4
+ */
+ entries = create.window_size >> create.page_shift;
+ pages = MAX((entries * sizeof(uint64_t)) / getpagesize(), 1);
+ pages = MAX(pow2ceil(pages) - 1, 1); /* Round up */
+ create.levels = ctz64(pages) / 6 + 1;
+
+ /* For now intersections are not allowed, we may relax this later */
+ QLIST_FOREACH(hostwin, &container->hostwin_list, hostwin_next) {
+ if (vfio_host_win_intersects(hostwin,
+ section->offset_within_address_space,
+ section->offset_within_address_space +
+ create.window_size - 1)) {
+ goto fail;
+ }
+ }
+
+ ret = ioctl(container->fd, VFIO_IOMMU_SPAPR_TCE_CREATE, &create);
+ if (ret) {
+ error_report("Failed to create a window, ret = %d (%m)", ret);
+ goto fail;
+ }
+
+ if (create.start_addr != section->offset_within_address_space) {
+ struct vfio_iommu_spapr_tce_remove remove = {
+ .argsz = sizeof(remove),
+ .start_addr = create.start_addr
+ };
+ error_report("Host doesn't support DMA window at %"HWADDR_PRIx", must
be %"PRIx64,
+ section->offset_within_address_space,
+ create.start_addr);
+ ioctl(container->fd, VFIO_IOMMU_SPAPR_TCE_REMOVE, &remove);
+ ret = -EINVAL;
+ goto fail;
+ }
+ trace_vfio_spapr_create_window(create.page_shift,
+ create.window_size,
+ create.start_addr);
+
+ vfio_host_win_add(container, create.start_addr,
+ create.start_addr + create.window_size - 1,
+ 1ULL << create.page_shift);
+ }
This is a function on its own, split it out and why not stop pretending
prereg is some sort of generic interface and let's just make a spapr
support file.
Yet another new file - spapr.c, or rename prereg.c to spapr.c and add this
stuff there?
Also, what bits? I'd keep VFIOHostDMAWindow business in here and moved
vfio_iommu_spapr_tce_create and ioctl to the new place, will this be ok?
Thanks.
+
if (!vfio_host_win_lookup(container, iova, end)) {
error_report("vfio: IOMMU container %p can't map guest IOVA region"
" 0x%"HWADDR_PRIx"..0x%"HWADDR_PRIx,
@@ -566,6 +649,22 @@ static void vfio_listener_region_del(MemoryListener
*listener,
container, iova, int128_get64(llsize), ret);
}
+ if (container->iommu_type == VFIO_SPAPR_TCE_v2_IOMMU) {
+ struct vfio_iommu_spapr_tce_remove remove = {
+ .argsz = sizeof(remove),
+ .start_addr = section->offset_within_address_space,
+ };
+ ret = ioctl(container->fd, VFIO_IOMMU_SPAPR_TCE_REMOVE, &remove);
+ if (ret) {
+ error_report("Failed to remove window at %"PRIx64,
+ remove.start_addr);
+ }
+
+ vfio_host_win_del(container, section->offset_within_address_space);
+
+ trace_vfio_spapr_remove_window(remove.start_addr);
+ }
This would be in that spapr file too.
+
if (iommu && iommu->iommu_ops && iommu->iommu_ops->vfio_stop) {
iommu->iommu_ops->vfio_stop(section->mr);
}
@@ -957,11 +1056,6 @@ static int vfio_connect_container(VFIOGroup *group,
AddressSpace *as)
}
}
- /*
- * This only considers the host IOMMU's 32-bit window. At
- * some point we need to add support for the optional 64-bit
- * window and dynamic windows
- */
info.argsz = sizeof(info);
ret = ioctl(fd, VFIO_IOMMU_SPAPR_TCE_GET_INFO, &info);
if (ret) {
@@ -970,11 +1064,30 @@ static int vfio_connect_container(VFIOGroup *group,
AddressSpace *as)
goto listener_release_exit;
}
- /* The default table uses 4K pages */
- vfio_host_win_add(container, info.dma32_window_start,
- info.dma32_window_start +
- info.dma32_window_size - 1,
- 0x1000);
+ if (v2) {
+ /*
+ * There is a default window in just created container.
+ * To make region_add/del simpler, we better remove this
+ * window now and let those iommu_listener callbacks
+ * create/remove them when needed.
+ */
+ struct vfio_iommu_spapr_tce_remove remove = {
+ .argsz = sizeof(remove),
+ .start_addr = info.dma32_window_start,
+ };
+ ret = ioctl(fd, VFIO_IOMMU_SPAPR_TCE_REMOVE, &remove);
+ if (ret) {
+ error_report("vfio: VFIO_IOMMU_SPAPR_TCE_REMOVE failed: %m");
+ ret = -errno;
+ goto free_container_exit;
+ }
+ } else {
+ /* The default table uses 4K pages */
+ vfio_host_win_add(container, info.dma32_window_start,
+ info.dma32_window_start +
+ info.dma32_window_size - 1,
+ 0x1000);
+ }
} else {
error_report("vfio: No available IOMMU models");
ret = -EINVAL;
diff --git a/trace-events b/trace-events
index d0d8615..b5419de 100644
--- a/trace-events
+++ b/trace-events
@@ -1739,6 +1739,8 @@ vfio_region_finalize(const char *name, int index) "Device %s,
region %d"
vfio_region_mmaps_set_enabled(const char *name, bool enabled) "Region %s mmaps
enabled: %d"
vfio_ram_register(uint64_t va, uint64_t size, int ret) "va=%"PRIx64" size=%"PRIx64"
ret=%d"
vfio_ram_unregister(uint64_t va, uint64_t size, int ret) "va=%"PRIx64"
size=%"PRIx64" ret=%d"
+vfio_spapr_create_window(int ps, uint64_t ws, uint64_t off) "pageshift=0x%x
winsize=0x%"PRIx64" offset=0x%"PRIx64
+vfio_spapr_remove_window(uint64_t off) "offset=%"PRIx64
# hw/vfio/platform.c
vfio_platform_base_device_init(char *name, int groupid) "%s belongs to group
#%d"
--
Alexey
