summary refs log tree commit diff stats
path: root/hw/vfio/iommufd.c
diff options
context:
space:
mode:
Diffstat (limited to 'hw/vfio/iommufd.c')
-rw-r--r--hw/vfio/iommufd.c630
1 files changed, 630 insertions, 0 deletions
diff --git a/hw/vfio/iommufd.c b/hw/vfio/iommufd.c
new file mode 100644
index 0000000000..87a561c545
--- /dev/null
+++ b/hw/vfio/iommufd.c
@@ -0,0 +1,630 @@
+/*
+ * 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)
+{
+    long int ret = -ENOTTY;
+    char *path, *vfio_dev_path = NULL, *vfio_path = NULL;
+    DIR *dir = NULL;
+    struct dirent *dent;
+    gchar *contents;
+    struct stat st;
+    gsize length;
+    int major, minor;
+    dev_t vfio_devt;
+
+    path = g_strdup_printf("%s/vfio-dev", sysfs_path);
+    if (stat(path, &st) < 0) {
+        error_setg_errno(errp, errno, "no such host device");
+        goto out_free_path;
+    }
+
+    dir = opendir(path);
+    if (!dir) {
+        error_setg_errno(errp, errno, "couldn't open directory %s", path);
+        goto out_free_path;
+    }
+
+    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_free_dev_path;
+    }
+
+    if (sscanf(contents, "%d:%d", &major, &minor) != 2) {
+        error_setg(errp, "failed to get major:minor for \"%s\"", vfio_dev_path);
+        goto out_free_dev_path;
+    }
+    g_free(contents);
+    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);
+    g_free(vfio_path);
+
+out_free_dev_path:
+    g_free(vfio_dev_path);
+out_close_dir:
+    closedir(dir);
+out_free_path:
+    if (*errp) {
+        error_prepend(errp, VFIO_MSG_PREFIX, path);
+    }
+    g_free(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;
+
+    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 != &vfio_iommufd_ops ||
+            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, &vfio_iommufd_ops);
+    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;
+    }
+
+    /*
+     * 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);
+    }
+
+    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;
+
+    QLIST_FOREACH(vbasedev_iter, &vfio_device_list, global_next) {
+        if (vbasedev_iter->bcontainer->ops != &vfio_iommufd_ops) {
+            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;
+}
+
+const VFIOIOMMUOps vfio_iommufd_ops = {
+    .dma_map = iommufd_cdev_map,
+    .dma_unmap = iommufd_cdev_unmap,
+    .attach_device = iommufd_cdev_attach,
+    .detach_device = iommufd_cdev_detach,
+    .pci_hot_reset = iommufd_cdev_pci_hot_reset,
+};