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authorEric Auger <eric.auger@linaro.org>2015-06-08 09:25:25 -0600
committerAlex Williamson <alex.williamson@redhat.com>2015-06-08 09:25:25 -0600
commit0ea2730bef0b764ce87f5d6859f9b1eac6069250 (patch)
tree56c3e63023f9f0b3c59d32bceed223ea99f99a20 /hw/vfio/platform.c
parent2e29dd7c44db30e3d3c108ab2a622cbdac6d16f0 (diff)
hw/vfio/platform: vfio-platform skeleton
Minimal VFIO platform implementation supporting register space user mapping but not IRQ assignment. Signed-off-by: Kim Phillips <kim.phillips@linaro.org> Signed-off-by: Eric Auger <eric.auger@linaro.org> Tested-by: Vikram Sethi <vikrams@codeaurora.org> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Diffstat (limited to 'hw/vfio/platform.c')
-rw-r--r--hw/vfio/platform.c287
1 files changed, 287 insertions, 0 deletions
diff --git a/hw/vfio/platform.c b/hw/vfio/platform.c
new file mode 100644
index 0000000000..569a675cb2
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+++ b/hw/vfio/platform.c
@@ -0,0 +1,287 @@
+/*
+ * vfio based device assignment support - platform devices
+ *
+ * Copyright Linaro Limited, 2014
+ *
+ * Authors:
+ * Kim Phillips <kim.phillips@linaro.org>
+ * Eric Auger <eric.auger@linaro.org>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2. See
+ * the COPYING file in the top-level directory.
+ *
+ * Based on vfio based PCI device assignment support:
+ * Copyright Red Hat, Inc. 2012
+ */
+
+#include <linux/vfio.h>
+#include <sys/ioctl.h>
+
+#include "hw/vfio/vfio-platform.h"
+#include "qemu/error-report.h"
+#include "qemu/range.h"
+#include "sysemu/sysemu.h"
+#include "exec/memory.h"
+#include "hw/sysbus.h"
+#include "trace.h"
+#include "hw/platform-bus.h"
+
+/* VFIO skeleton */
+
+static void vfio_platform_compute_needs_reset(VFIODevice *vbasedev)
+{
+ vbasedev->needs_reset = true;
+}
+
+/* not implemented yet */
+static int vfio_platform_hot_reset_multi(VFIODevice *vbasedev)
+{
+ return -1;
+}
+
+/**
+ * vfio_populate_device - Allocate and populate MMIO region
+ * structs according to driver returned information
+ * @vbasedev: the VFIO device handle
+ *
+ */
+static int vfio_populate_device(VFIODevice *vbasedev)
+{
+ int i, ret = -1;
+ VFIOPlatformDevice *vdev =
+ container_of(vbasedev, VFIOPlatformDevice, vbasedev);
+
+ if (!(vbasedev->flags & VFIO_DEVICE_FLAGS_PLATFORM)) {
+ error_report("vfio: Um, this isn't a platform device");
+ return ret;
+ }
+
+ vdev->regions = g_malloc0_n(vbasedev->num_regions,
+ sizeof(VFIORegion *));
+
+ for (i = 0; i < vbasedev->num_regions; i++) {
+ struct vfio_region_info reg_info = { .argsz = sizeof(reg_info) };
+ VFIORegion *ptr;
+
+ vdev->regions[i] = g_malloc0(sizeof(VFIORegion));
+ ptr = vdev->regions[i];
+ reg_info.index = i;
+ ret = ioctl(vbasedev->fd, VFIO_DEVICE_GET_REGION_INFO, &reg_info);
+ if (ret) {
+ error_report("vfio: Error getting region %d info: %m", i);
+ goto reg_error;
+ }
+ ptr->flags = reg_info.flags;
+ ptr->size = reg_info.size;
+ ptr->fd_offset = reg_info.offset;
+ ptr->nr = i;
+ ptr->vbasedev = vbasedev;
+
+ trace_vfio_platform_populate_regions(ptr->nr,
+ (unsigned long)ptr->flags,
+ (unsigned long)ptr->size,
+ ptr->vbasedev->fd,
+ (unsigned long)ptr->fd_offset);
+ }
+
+ return 0;
+reg_error:
+ for (i = 0; i < vbasedev->num_regions; i++) {
+ g_free(vdev->regions[i]);
+ }
+ g_free(vdev->regions);
+ return ret;
+}
+
+/* specialized functions for VFIO Platform devices */
+static VFIODeviceOps vfio_platform_ops = {
+ .vfio_compute_needs_reset = vfio_platform_compute_needs_reset,
+ .vfio_hot_reset_multi = vfio_platform_hot_reset_multi,
+};
+
+/**
+ * vfio_base_device_init - perform preliminary VFIO setup
+ * @vbasedev: the VFIO device handle
+ *
+ * Implement the VFIO command sequence that allows to discover
+ * assigned device resources: group extraction, device
+ * fd retrieval, resource query.
+ * Precondition: the device name must be initialized
+ */
+static int vfio_base_device_init(VFIODevice *vbasedev)
+{
+ VFIOGroup *group;
+ VFIODevice *vbasedev_iter;
+ char path[PATH_MAX], iommu_group_path[PATH_MAX], *group_name;
+ ssize_t len;
+ struct stat st;
+ int groupid;
+ int ret;
+
+ /* name must be set prior to the call */
+ if (!vbasedev->name || strchr(vbasedev->name, '/')) {
+ return -EINVAL;
+ }
+
+ /* Check that the host device exists */
+ g_snprintf(path, sizeof(path), "/sys/bus/platform/devices/%s/",
+ vbasedev->name);
+
+ if (stat(path, &st) < 0) {
+ error_report("vfio: error: no such host device: %s", path);
+ return -errno;
+ }
+
+ g_strlcat(path, "iommu_group", sizeof(path));
+ len = readlink(path, iommu_group_path, sizeof(iommu_group_path));
+ if (len < 0 || len >= sizeof(iommu_group_path)) {
+ error_report("vfio: error no iommu_group for device");
+ return len < 0 ? -errno : -ENAMETOOLONG;
+ }
+
+ iommu_group_path[len] = 0;
+ group_name = basename(iommu_group_path);
+
+ if (sscanf(group_name, "%d", &groupid) != 1) {
+ error_report("vfio: error reading %s: %m", path);
+ return -errno;
+ }
+
+ trace_vfio_platform_base_device_init(vbasedev->name, groupid);
+
+ group = vfio_get_group(groupid, &address_space_memory);
+ if (!group) {
+ error_report("vfio: failed to get group %d", groupid);
+ return -ENOENT;
+ }
+
+ g_snprintf(path, sizeof(path), "%s", vbasedev->name);
+
+ QLIST_FOREACH(vbasedev_iter, &group->device_list, next) {
+ if (strcmp(vbasedev_iter->name, vbasedev->name) == 0) {
+ error_report("vfio: error: device %s is already attached", path);
+ vfio_put_group(group);
+ return -EBUSY;
+ }
+ }
+ ret = vfio_get_device(group, path, vbasedev);
+ if (ret) {
+ error_report("vfio: failed to get device %s", path);
+ vfio_put_group(group);
+ return ret;
+ }
+
+ ret = vfio_populate_device(vbasedev);
+ if (ret) {
+ error_report("vfio: failed to populate device %s", path);
+ vfio_put_group(group);
+ }
+
+ return ret;
+}
+
+/**
+ * vfio_map_region - initialize the 2 memory regions for a given
+ * MMIO region index
+ * @vdev: the VFIO platform device handle
+ * @nr: the index of the region
+ *
+ * Init the top memory region and the mmapped memory region beneath
+ * VFIOPlatformDevice is used since VFIODevice is not a QOM Object
+ * and could not be passed to memory region functions
+*/
+static void vfio_map_region(VFIOPlatformDevice *vdev, int nr)
+{
+ VFIORegion *region = vdev->regions[nr];
+ uint64_t size = region->size;
+ char name[64];
+
+ if (!size) {
+ return;
+ }
+
+ g_snprintf(name, sizeof(name), "VFIO %s region %d",
+ vdev->vbasedev.name, nr);
+
+ /* A "slow" read/write mapping underlies all regions */
+ memory_region_init_io(&region->mem, OBJECT(vdev), &vfio_region_ops,
+ region, name, size);
+
+ g_strlcat(name, " mmap", sizeof(name));
+
+ if (vfio_mmap_region(OBJECT(vdev), region, &region->mem,
+ &region->mmap_mem, &region->mmap, size, 0, name)) {
+ error_report("%s unsupported. Performance may be slow", name);
+ }
+}
+
+/**
+ * vfio_platform_realize - the device realize function
+ * @dev: device state pointer
+ * @errp: error
+ *
+ * initialize the device, its memory regions and IRQ structures
+ * IRQ are started separately
+ */
+static void vfio_platform_realize(DeviceState *dev, Error **errp)
+{
+ VFIOPlatformDevice *vdev = VFIO_PLATFORM_DEVICE(dev);
+ SysBusDevice *sbdev = SYS_BUS_DEVICE(dev);
+ VFIODevice *vbasedev = &vdev->vbasedev;
+ int i, ret;
+
+ vbasedev->type = VFIO_DEVICE_TYPE_PLATFORM;
+ vbasedev->ops = &vfio_platform_ops;
+
+ trace_vfio_platform_realize(vbasedev->name, vdev->compat);
+
+ ret = vfio_base_device_init(vbasedev);
+ if (ret) {
+ error_setg(errp, "vfio: vfio_base_device_init failed for %s",
+ vbasedev->name);
+ return;
+ }
+
+ for (i = 0; i < vbasedev->num_regions; i++) {
+ vfio_map_region(vdev, i);
+ sysbus_init_mmio(sbdev, &vdev->regions[i]->mem);
+ }
+}
+
+static const VMStateDescription vfio_platform_vmstate = {
+ .name = TYPE_VFIO_PLATFORM,
+ .unmigratable = 1,
+};
+
+static Property vfio_platform_dev_properties[] = {
+ DEFINE_PROP_STRING("host", VFIOPlatformDevice, vbasedev.name),
+ DEFINE_PROP_BOOL("x-mmap", VFIOPlatformDevice, vbasedev.allow_mmap, true),
+ DEFINE_PROP_END_OF_LIST(),
+};
+
+static void vfio_platform_class_init(ObjectClass *klass, void *data)
+{
+ DeviceClass *dc = DEVICE_CLASS(klass);
+
+ dc->realize = vfio_platform_realize;
+ dc->props = vfio_platform_dev_properties;
+ dc->vmsd = &vfio_platform_vmstate;
+ dc->desc = "VFIO-based platform device assignment";
+ set_bit(DEVICE_CATEGORY_MISC, dc->categories);
+}
+
+static const TypeInfo vfio_platform_dev_info = {
+ .name = TYPE_VFIO_PLATFORM,
+ .parent = TYPE_SYS_BUS_DEVICE,
+ .instance_size = sizeof(VFIOPlatformDevice),
+ .class_init = vfio_platform_class_init,
+ .class_size = sizeof(VFIOPlatformDeviceClass),
+ .abstract = true,
+};
+
+static void register_vfio_platform_dev_type(void)
+{
+ type_register_static(&vfio_platform_dev_info);
+}
+
+type_init(register_vfio_platform_dev_type)