qemu/hw/vfio/iommufd.c

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/*
* iommufd container backend
*
* Copyright (C) 2023 Intel Corporation.
* Copyright Red Hat, Inc. 2023
*
* Authors: Yi Liu <yi.l.liu@intel.com>
* Eric Auger <eric.auger@redhat.com>
*
* SPDX-License-Identifier: GPL-2.0-or-later
*/
#include "qemu/osdep.h"
#include <sys/ioctl.h>
#include <linux/vfio.h>
#include <linux/iommufd.h>
#include "hw/vfio/vfio-common.h"
#include "qemu/error-report.h"
#include "trace.h"
#include "qapi/error.h"
#include "sysemu/iommufd.h"
#include "hw/qdev-core.h"
#include "sysemu/reset.h"
#include "qemu/cutils.h"
#include "qemu/chardev_open.h"
#include "pci.h"
static int iommufd_cdev_map(const VFIOContainerBase *bcontainer, hwaddr iova,
ram_addr_t size, void *vaddr, bool readonly)
{
const VFIOIOMMUFDContainer *container =
container_of(bcontainer, VFIOIOMMUFDContainer, bcontainer);
return iommufd_backend_map_dma(container->be,
container->ioas_id,
iova, size, vaddr, readonly);
}
static int iommufd_cdev_unmap(const VFIOContainerBase *bcontainer,
hwaddr iova, ram_addr_t size,
IOMMUTLBEntry *iotlb)
{
const VFIOIOMMUFDContainer *container =
container_of(bcontainer, VFIOIOMMUFDContainer, bcontainer);
/* TODO: Handle dma_unmap_bitmap with iotlb args (migration) */
return iommufd_backend_unmap_dma(container->be,
container->ioas_id, iova, size);
}
static int iommufd_cdev_kvm_device_add(VFIODevice *vbasedev, Error **errp)
{
return vfio_kvm_device_add_fd(vbasedev->fd, errp);
}
static void iommufd_cdev_kvm_device_del(VFIODevice *vbasedev)
{
Error *err = NULL;
if (vfio_kvm_device_del_fd(vbasedev->fd, &err)) {
error_report_err(err);
}
}
static int iommufd_cdev_connect_and_bind(VFIODevice *vbasedev, Error **errp)
{
IOMMUFDBackend *iommufd = vbasedev->iommufd;
struct vfio_device_bind_iommufd bind = {
.argsz = sizeof(bind),
.flags = 0,
};
int ret;
ret = iommufd_backend_connect(iommufd, errp);
if (ret) {
return ret;
}
/*
* Add device to kvm-vfio to be prepared for the tracking
* in KVM. Especially for some emulated devices, it requires
* to have kvm information in the device open.
*/
ret = iommufd_cdev_kvm_device_add(vbasedev, errp);
if (ret) {
goto err_kvm_device_add;
}
/* Bind device to iommufd */
bind.iommufd = iommufd->fd;
ret = ioctl(vbasedev->fd, VFIO_DEVICE_BIND_IOMMUFD, &bind);
if (ret) {
error_setg_errno(errp, errno, "error bind device fd=%d to iommufd=%d",
vbasedev->fd, bind.iommufd);
goto err_bind;
}
vbasedev->devid = bind.out_devid;
trace_iommufd_cdev_connect_and_bind(bind.iommufd, vbasedev->name,
vbasedev->fd, vbasedev->devid);
return ret;
err_bind:
iommufd_cdev_kvm_device_del(vbasedev);
err_kvm_device_add:
iommufd_backend_disconnect(iommufd);
return ret;
}
static void iommufd_cdev_unbind_and_disconnect(VFIODevice *vbasedev)
{
/* Unbind is automatically conducted when device fd is closed */
iommufd_cdev_kvm_device_del(vbasedev);
iommufd_backend_disconnect(vbasedev->iommufd);
}
static int iommufd_cdev_getfd(const char *sysfs_path, Error **errp)
{
hw/vfio/iommufd: Fix missing ERRP_GUARD() for error_prepend() As the comment in qapi/error, passing @errp to error_prepend() requires ERRP_GUARD(): * = Why, when and how to use ERRP_GUARD() = * * Without ERRP_GUARD(), use of the @errp parameter is restricted: ... * - It should not be passed to error_prepend(), error_vprepend() or * error_append_hint(), because that doesn't work with &error_fatal. * ERRP_GUARD() lifts these restrictions. * * To use ERRP_GUARD(), add it right at the beginning of the function. * @errp can then be used without worrying about the argument being * NULL or &error_fatal. ERRP_GUARD() could avoid the case when @errp is &error_fatal, the user can't see this additional information, because exit() happens in error_setg earlier than information is added [1]. The iommufd_cdev_getfd() passes @errp to error_prepend(). Its @errp is from vfio_attach_device(), and there are too many possible callers to check the impact of this defect; it may or may not be harmless. Thus it is necessary to protect @errp with ERRP_GUARD(). To avoid the issue like [1] said, add missing ERRP_GUARD() at the beginning of this function. [1]: Issue description in the commit message of commit ae7c80a7bd73 ("error: New macro ERRP_GUARD()"). Cc: Alex Williamson <alex.williamson@redhat.com> Cc: Cédric Le Goater <clg@redhat.com> Signed-off-by: Zhao Liu <zhao1.liu@intel.com> Reviewed-by: Cédric Le Goater <clg@redhat.com> Message-ID: <20240311033822.3142585-22-zhao1.liu@linux.intel.com> Signed-off-by: Thomas Huth <thuth@redhat.com>
2024-03-11 06:38:14 +03:00
ERRP_GUARD();
long int ret = -ENOTTY;
g_autofree char *path = NULL;
g_autofree char *vfio_dev_path = NULL;
g_autofree char *vfio_path = NULL;
DIR *dir = NULL;
struct dirent *dent;
g_autofree gchar *contents = NULL;
gsize length;
int major, minor;
dev_t vfio_devt;
path = g_strdup_printf("%s/vfio-dev", sysfs_path);
dir = opendir(path);
if (!dir) {
error_setg_errno(errp, errno, "couldn't open directory %s", path);
goto out;
}
while ((dent = readdir(dir))) {
if (!strncmp(dent->d_name, "vfio", 4)) {
vfio_dev_path = g_strdup_printf("%s/%s/dev", path, dent->d_name);
break;
}
}
if (!vfio_dev_path) {
error_setg(errp, "failed to find vfio-dev/vfioX/dev");
goto out_close_dir;
}
if (!g_file_get_contents(vfio_dev_path, &contents, &length, NULL)) {
error_setg(errp, "failed to load \"%s\"", vfio_dev_path);
goto out_close_dir;
}
if (sscanf(contents, "%d:%d", &major, &minor) != 2) {
error_setg(errp, "failed to get major:minor for \"%s\"", vfio_dev_path);
goto out_close_dir;
}
vfio_devt = makedev(major, minor);
vfio_path = g_strdup_printf("/dev/vfio/devices/%s", dent->d_name);
ret = open_cdev(vfio_path, vfio_devt);
if (ret < 0) {
error_setg(errp, "Failed to open %s", vfio_path);
}
trace_iommufd_cdev_getfd(vfio_path, ret);
out_close_dir:
closedir(dir);
out:
if (*errp) {
error_prepend(errp, VFIO_MSG_PREFIX, path);
}
return ret;
}
static int iommufd_cdev_attach_ioas_hwpt(VFIODevice *vbasedev, uint32_t id,
Error **errp)
{
int ret, iommufd = vbasedev->iommufd->fd;
struct vfio_device_attach_iommufd_pt attach_data = {
.argsz = sizeof(attach_data),
.flags = 0,
.pt_id = id,
};
/* Attach device to an IOAS or hwpt within iommufd */
ret = ioctl(vbasedev->fd, VFIO_DEVICE_ATTACH_IOMMUFD_PT, &attach_data);
if (ret) {
error_setg_errno(errp, errno,
"[iommufd=%d] error attach %s (%d) to id=%d",
iommufd, vbasedev->name, vbasedev->fd, id);
} else {
trace_iommufd_cdev_attach_ioas_hwpt(iommufd, vbasedev->name,
vbasedev->fd, id);
}
return ret;
}
static int iommufd_cdev_detach_ioas_hwpt(VFIODevice *vbasedev, Error **errp)
{
int ret, iommufd = vbasedev->iommufd->fd;
struct vfio_device_detach_iommufd_pt detach_data = {
.argsz = sizeof(detach_data),
.flags = 0,
};
ret = ioctl(vbasedev->fd, VFIO_DEVICE_DETACH_IOMMUFD_PT, &detach_data);
if (ret) {
error_setg_errno(errp, errno, "detach %s failed", vbasedev->name);
} else {
trace_iommufd_cdev_detach_ioas_hwpt(iommufd, vbasedev->name);
}
return ret;
}
static int iommufd_cdev_attach_container(VFIODevice *vbasedev,
VFIOIOMMUFDContainer *container,
Error **errp)
{
return iommufd_cdev_attach_ioas_hwpt(vbasedev, container->ioas_id, errp);
}
static void iommufd_cdev_detach_container(VFIODevice *vbasedev,
VFIOIOMMUFDContainer *container)
{
Error *err = NULL;
if (iommufd_cdev_detach_ioas_hwpt(vbasedev, &err)) {
error_report_err(err);
}
}
static void iommufd_cdev_container_destroy(VFIOIOMMUFDContainer *container)
{
VFIOContainerBase *bcontainer = &container->bcontainer;
if (!QLIST_EMPTY(&bcontainer->device_list)) {
return;
}
memory_listener_unregister(&bcontainer->listener);
vfio_container_destroy(bcontainer);
iommufd_backend_free_id(container->be, container->ioas_id);
g_free(container);
}
static int iommufd_cdev_ram_block_discard_disable(bool state)
{
/*
* We support coordinated discarding of RAM via the RamDiscardManager.
*/
return ram_block_uncoordinated_discard_disable(state);
}
static int iommufd_cdev_get_info_iova_range(VFIOIOMMUFDContainer *container,
uint32_t ioas_id, Error **errp)
{
VFIOContainerBase *bcontainer = &container->bcontainer;
struct iommu_ioas_iova_ranges *info;
struct iommu_iova_range *iova_ranges;
int ret, sz, fd = container->be->fd;
info = g_malloc0(sizeof(*info));
info->size = sizeof(*info);
info->ioas_id = ioas_id;
ret = ioctl(fd, IOMMU_IOAS_IOVA_RANGES, info);
if (ret && errno != EMSGSIZE) {
goto error;
}
sz = info->num_iovas * sizeof(struct iommu_iova_range);
info = g_realloc(info, sizeof(*info) + sz);
info->allowed_iovas = (uintptr_t)(info + 1);
ret = ioctl(fd, IOMMU_IOAS_IOVA_RANGES, info);
if (ret) {
goto error;
}
iova_ranges = (struct iommu_iova_range *)(uintptr_t)info->allowed_iovas;
for (int i = 0; i < info->num_iovas; i++) {
Range *range = g_new(Range, 1);
range_set_bounds(range, iova_ranges[i].start, iova_ranges[i].last);
bcontainer->iova_ranges =
range_list_insert(bcontainer->iova_ranges, range);
}
bcontainer->pgsizes = info->out_iova_alignment;
g_free(info);
return 0;
error:
ret = -errno;
g_free(info);
error_setg_errno(errp, errno, "Cannot get IOVA ranges");
return ret;
}
static int iommufd_cdev_attach(const char *name, VFIODevice *vbasedev,
AddressSpace *as, Error **errp)
{
VFIOContainerBase *bcontainer;
VFIOIOMMUFDContainer *container;
VFIOAddressSpace *space;
struct vfio_device_info dev_info = { .argsz = sizeof(dev_info) };
int ret, devfd;
uint32_t ioas_id;
Error *err = NULL;
const VFIOIOMMUClass *iommufd_vioc =
VFIO_IOMMU_CLASS(object_class_by_name(TYPE_VFIO_IOMMU_IOMMUFD));
if (vbasedev->fd < 0) {
devfd = iommufd_cdev_getfd(vbasedev->sysfsdev, errp);
if (devfd < 0) {
return devfd;
}
vbasedev->fd = devfd;
} else {
devfd = vbasedev->fd;
}
ret = iommufd_cdev_connect_and_bind(vbasedev, errp);
if (ret) {
goto err_connect_bind;
}
space = vfio_get_address_space(as);
/* try to attach to an existing container in this space */
QLIST_FOREACH(bcontainer, &space->containers, next) {
container = container_of(bcontainer, VFIOIOMMUFDContainer, bcontainer);
if (bcontainer->ops != iommufd_vioc ||
vbasedev->iommufd != container->be) {
continue;
}
if (iommufd_cdev_attach_container(vbasedev, container, &err)) {
const char *msg = error_get_pretty(err);
trace_iommufd_cdev_fail_attach_existing_container(msg);
error_free(err);
err = NULL;
} else {
ret = iommufd_cdev_ram_block_discard_disable(true);
if (ret) {
error_setg(errp,
"Cannot set discarding of RAM broken (%d)", ret);
goto err_discard_disable;
}
goto found_container;
}
}
/* Need to allocate a new dedicated container */
ret = iommufd_backend_alloc_ioas(vbasedev->iommufd, &ioas_id, errp);
if (ret < 0) {
goto err_alloc_ioas;
}
trace_iommufd_cdev_alloc_ioas(vbasedev->iommufd->fd, ioas_id);
container = g_malloc0(sizeof(*container));
container->be = vbasedev->iommufd;
container->ioas_id = ioas_id;
bcontainer = &container->bcontainer;
vfio_container_init(bcontainer, space, iommufd_vioc);
QLIST_INSERT_HEAD(&space->containers, bcontainer, next);
ret = iommufd_cdev_attach_container(vbasedev, container, errp);
if (ret) {
goto err_attach_container;
}
ret = iommufd_cdev_ram_block_discard_disable(true);
if (ret) {
goto err_discard_disable;
}
ret = iommufd_cdev_get_info_iova_range(container, ioas_id, &err);
if (ret) {
error_append_hint(&err,
"Fallback to default 64bit IOVA range and 4K page size\n");
warn_report_err(err);
err = NULL;
bcontainer->pgsizes = qemu_real_host_page_size();
}
bcontainer->listener = vfio_memory_listener;
memory_listener_register(&bcontainer->listener, bcontainer->space->as);
if (bcontainer->error) {
ret = -1;
error_propagate_prepend(errp, bcontainer->error,
"memory listener initialization failed: ");
goto err_listener_register;
}
bcontainer->initialized = true;
found_container:
ret = ioctl(devfd, VFIO_DEVICE_GET_INFO, &dev_info);
if (ret) {
error_setg_errno(errp, errno, "error getting device info");
goto err_listener_register;
}
ret = vfio_cpr_register_container(bcontainer, errp);
if (ret) {
goto err_listener_register;
}
/*
* TODO: examine RAM_BLOCK_DISCARD stuff, should we do group level
* for discarding incompatibility check as well?
*/
if (vbasedev->ram_block_discard_allowed) {
iommufd_cdev_ram_block_discard_disable(false);
}
vbasedev->group = 0;
vbasedev->num_irqs = dev_info.num_irqs;
vbasedev->num_regions = dev_info.num_regions;
vbasedev->flags = dev_info.flags;
vbasedev->reset_works = !!(dev_info.flags & VFIO_DEVICE_FLAGS_RESET);
vbasedev->bcontainer = bcontainer;
QLIST_INSERT_HEAD(&bcontainer->device_list, vbasedev, container_next);
QLIST_INSERT_HEAD(&vfio_device_list, vbasedev, global_next);
trace_iommufd_cdev_device_info(vbasedev->name, devfd, vbasedev->num_irqs,
vbasedev->num_regions, vbasedev->flags);
return 0;
err_listener_register:
iommufd_cdev_ram_block_discard_disable(false);
err_discard_disable:
iommufd_cdev_detach_container(vbasedev, container);
err_attach_container:
iommufd_cdev_container_destroy(container);
err_alloc_ioas:
vfio_put_address_space(space);
iommufd_cdev_unbind_and_disconnect(vbasedev);
err_connect_bind:
close(vbasedev->fd);
return ret;
}
static void iommufd_cdev_detach(VFIODevice *vbasedev)
{
VFIOContainerBase *bcontainer = vbasedev->bcontainer;
VFIOAddressSpace *space = bcontainer->space;
VFIOIOMMUFDContainer *container = container_of(bcontainer,
VFIOIOMMUFDContainer,
bcontainer);
QLIST_REMOVE(vbasedev, global_next);
QLIST_REMOVE(vbasedev, container_next);
vbasedev->bcontainer = NULL;
if (!vbasedev->ram_block_discard_allowed) {
iommufd_cdev_ram_block_discard_disable(false);
}
vfio_cpr_unregister_container(bcontainer);
iommufd_cdev_detach_container(vbasedev, container);
iommufd_cdev_container_destroy(container);
vfio_put_address_space(space);
iommufd_cdev_unbind_and_disconnect(vbasedev);
close(vbasedev->fd);
}
static VFIODevice *iommufd_cdev_pci_find_by_devid(__u32 devid)
{
VFIODevice *vbasedev_iter;
const VFIOIOMMUClass *iommufd_vioc =
VFIO_IOMMU_CLASS(object_class_by_name(TYPE_VFIO_IOMMU_IOMMUFD));
QLIST_FOREACH(vbasedev_iter, &vfio_device_list, global_next) {
if (vbasedev_iter->bcontainer->ops != iommufd_vioc) {
continue;
}
if (devid == vbasedev_iter->devid) {
return vbasedev_iter;
}
}
return NULL;
}
static VFIOPCIDevice *
iommufd_cdev_dep_get_realized_vpdev(struct vfio_pci_dependent_device *dep_dev,
VFIODevice *reset_dev)
{
VFIODevice *vbasedev_tmp;
if (dep_dev->devid == reset_dev->devid ||
dep_dev->devid == VFIO_PCI_DEVID_OWNED) {
return NULL;
}
vbasedev_tmp = iommufd_cdev_pci_find_by_devid(dep_dev->devid);
if (!vbasedev_tmp || !vbasedev_tmp->dev->realized ||
vbasedev_tmp->type != VFIO_DEVICE_TYPE_PCI) {
return NULL;
}
return container_of(vbasedev_tmp, VFIOPCIDevice, vbasedev);
}
static int iommufd_cdev_pci_hot_reset(VFIODevice *vbasedev, bool single)
{
VFIOPCIDevice *vdev = container_of(vbasedev, VFIOPCIDevice, vbasedev);
struct vfio_pci_hot_reset_info *info = NULL;
struct vfio_pci_dependent_device *devices;
struct vfio_pci_hot_reset *reset;
int ret, i;
bool multi = false;
trace_vfio_pci_hot_reset(vdev->vbasedev.name, single ? "one" : "multi");
if (!single) {
vfio_pci_pre_reset(vdev);
}
vdev->vbasedev.needs_reset = false;
ret = vfio_pci_get_pci_hot_reset_info(vdev, &info);
if (ret) {
goto out_single;
}
assert(info->flags & VFIO_PCI_HOT_RESET_FLAG_DEV_ID);
devices = &info->devices[0];
if (!(info->flags & VFIO_PCI_HOT_RESET_FLAG_DEV_ID_OWNED)) {
if (!vdev->has_pm_reset) {
for (i = 0; i < info->count; i++) {
if (devices[i].devid == VFIO_PCI_DEVID_NOT_OWNED) {
error_report("vfio: Cannot reset device %s, "
"depends on device %04x:%02x:%02x.%x "
"which is not owned.",
vdev->vbasedev.name, devices[i].segment,
devices[i].bus, PCI_SLOT(devices[i].devfn),
PCI_FUNC(devices[i].devfn));
}
}
}
ret = -EPERM;
goto out_single;
}
trace_vfio_pci_hot_reset_has_dep_devices(vdev->vbasedev.name);
for (i = 0; i < info->count; i++) {
VFIOPCIDevice *tmp;
trace_iommufd_cdev_pci_hot_reset_dep_devices(devices[i].segment,
devices[i].bus,
PCI_SLOT(devices[i].devfn),
PCI_FUNC(devices[i].devfn),
devices[i].devid);
/*
* If a VFIO cdev device is resettable, all the dependent devices
* are either bound to same iommufd or within same iommu_groups as
* one of the iommufd bound devices.
*/
assert(devices[i].devid != VFIO_PCI_DEVID_NOT_OWNED);
tmp = iommufd_cdev_dep_get_realized_vpdev(&devices[i], &vdev->vbasedev);
if (!tmp) {
continue;
}
if (single) {
ret = -EINVAL;
goto out_single;
}
vfio_pci_pre_reset(tmp);
tmp->vbasedev.needs_reset = false;
multi = true;
}
if (!single && !multi) {
ret = -EINVAL;
goto out_single;
}
/* Use zero length array for hot reset with iommufd backend */
reset = g_malloc0(sizeof(*reset));
reset->argsz = sizeof(*reset);
/* Bus reset! */
ret = ioctl(vdev->vbasedev.fd, VFIO_DEVICE_PCI_HOT_RESET, reset);
g_free(reset);
if (ret) {
ret = -errno;
}
trace_vfio_pci_hot_reset_result(vdev->vbasedev.name,
ret ? strerror(errno) : "Success");
/* Re-enable INTx on affected devices */
for (i = 0; i < info->count; i++) {
VFIOPCIDevice *tmp;
tmp = iommufd_cdev_dep_get_realized_vpdev(&devices[i], &vdev->vbasedev);
if (!tmp) {
continue;
}
vfio_pci_post_reset(tmp);
}
out_single:
if (!single) {
vfio_pci_post_reset(vdev);
}
g_free(info);
return ret;
}
static void vfio_iommu_iommufd_class_init(ObjectClass *klass, void *data)
{
VFIOIOMMUClass *vioc = VFIO_IOMMU_CLASS(klass);
vioc->dma_map = iommufd_cdev_map;
vioc->dma_unmap = iommufd_cdev_unmap;
vioc->attach_device = iommufd_cdev_attach;
vioc->detach_device = iommufd_cdev_detach;
vioc->pci_hot_reset = iommufd_cdev_pci_hot_reset;
};
static const TypeInfo types[] = {
{
.name = TYPE_VFIO_IOMMU_IOMMUFD,
.parent = TYPE_VFIO_IOMMU,
.class_init = vfio_iommu_iommufd_class_init,
},
};
DEFINE_TYPES(types)