diff options
Diffstat (limited to 'hw/vfio/container.c')
| -rw-r--r-- | hw/vfio/container.c | 1161 |
1 files changed, 1161 insertions, 0 deletions
diff --git a/hw/vfio/container.c b/hw/vfio/container.c new file mode 100644 index 0000000..adc4672 --- /dev/null +++ b/hw/vfio/container.c @@ -0,0 +1,1161 @@ +/* + * generic functions used by VFIO devices + * + * Copyright Red Hat, Inc. 2012 + * + * Authors: + * Alex Williamson <alex.williamson@redhat.com> + * + * This work is licensed under the terms of the GNU GPL, version 2. See + * the COPYING file in the top-level directory. + * + * Based on qemu-kvm device-assignment: + * Adapted for KVM by Qumranet. + * Copyright (c) 2007, Neocleus, Alex Novik (alex@neocleus.com) + * Copyright (c) 2007, Neocleus, Guy Zana (guy@neocleus.com) + * Copyright (C) 2008, Qumranet, Amit Shah (amit.shah@qumranet.com) + * Copyright (C) 2008, Red Hat, Amit Shah (amit.shah@redhat.com) + * Copyright (C) 2008, IBM, Muli Ben-Yehuda (muli@il.ibm.com) + */ + +#include "qemu/osdep.h" +#include <sys/ioctl.h> +#ifdef CONFIG_KVM +#include <linux/kvm.h> +#endif +#include <linux/vfio.h> + +#include "hw/vfio/vfio-common.h" +#include "hw/vfio/vfio.h" +#include "exec/address-spaces.h" +#include "exec/memory.h" +#include "exec/ram_addr.h" +#include "hw/hw.h" +#include "qemu/error-report.h" +#include "qemu/range.h" +#include "sysemu/kvm.h" +#include "sysemu/reset.h" +#include "trace.h" +#include "qapi/error.h" +#include "migration/migration.h" + +VFIOGroupList vfio_group_list = + QLIST_HEAD_INITIALIZER(vfio_group_list); + +static int vfio_ram_block_discard_disable(VFIOContainer *container, bool state) +{ + switch (container->iommu_type) { + case VFIO_TYPE1v2_IOMMU: + case VFIO_TYPE1_IOMMU: + /* + * We support coordinated discarding of RAM via the RamDiscardManager. + */ + return ram_block_uncoordinated_discard_disable(state); + default: + /* + * VFIO_SPAPR_TCE_IOMMU most probably works just fine with + * RamDiscardManager, however, it is completely untested. + * + * VFIO_SPAPR_TCE_v2_IOMMU with "DMA memory preregistering" does + * completely the opposite of managing mapping/pinning dynamically as + * required by RamDiscardManager. We would have to special-case sections + * with a RamDiscardManager. + */ + return ram_block_discard_disable(state); + } +} + +static int vfio_dma_unmap_bitmap(VFIOContainer *container, + hwaddr iova, ram_addr_t size, + IOMMUTLBEntry *iotlb) +{ + struct vfio_iommu_type1_dma_unmap *unmap; + struct vfio_bitmap *bitmap; + VFIOBitmap vbmap; + int ret; + + ret = vfio_bitmap_alloc(&vbmap, size); + if (ret) { + return ret; + } + + unmap = g_malloc0(sizeof(*unmap) + sizeof(*bitmap)); + + unmap->argsz = sizeof(*unmap) + sizeof(*bitmap); + unmap->iova = iova; + unmap->size = size; + unmap->flags |= VFIO_DMA_UNMAP_FLAG_GET_DIRTY_BITMAP; + bitmap = (struct vfio_bitmap *)&unmap->data; + + /* + * cpu_physical_memory_set_dirty_lebitmap() supports pages in bitmap of + * qemu_real_host_page_size to mark those dirty. Hence set bitmap_pgsize + * to qemu_real_host_page_size. + */ + bitmap->pgsize = qemu_real_host_page_size(); + bitmap->size = vbmap.size; + bitmap->data = (__u64 *)vbmap.bitmap; + + if (vbmap.size > container->max_dirty_bitmap_size) { + error_report("UNMAP: Size of bitmap too big 0x%"PRIx64, vbmap.size); + ret = -E2BIG; + goto unmap_exit; + } + + ret = ioctl(container->fd, VFIO_IOMMU_UNMAP_DMA, unmap); + if (!ret) { + cpu_physical_memory_set_dirty_lebitmap(vbmap.bitmap, + iotlb->translated_addr, vbmap.pages); + } else { + error_report("VFIO_UNMAP_DMA with DIRTY_BITMAP : %m"); + } + +unmap_exit: + g_free(unmap); + g_free(vbmap.bitmap); + + return ret; +} + +/* + * DMA - Mapping and unmapping for the "type1" IOMMU interface used on x86 + */ +int vfio_dma_unmap(VFIOContainer *container, hwaddr iova, + ram_addr_t size, IOMMUTLBEntry *iotlb) +{ + struct vfio_iommu_type1_dma_unmap unmap = { + .argsz = sizeof(unmap), + .flags = 0, + .iova = iova, + .size = size, + }; + bool need_dirty_sync = false; + int ret; + + if (iotlb && vfio_devices_all_running_and_mig_active(container)) { + if (!vfio_devices_all_device_dirty_tracking(container) && + container->dirty_pages_supported) { + return vfio_dma_unmap_bitmap(container, iova, size, iotlb); + } + + need_dirty_sync = true; + } + + while (ioctl(container->fd, VFIO_IOMMU_UNMAP_DMA, &unmap)) { + /* + * The type1 backend has an off-by-one bug in the kernel (71a7d3d78e3c + * v4.15) where an overflow in its wrap-around check prevents us from + * unmapping the last page of the address space. Test for the error + * condition and re-try the unmap excluding the last page. The + * expectation is that we've never mapped the last page anyway and this + * unmap request comes via vIOMMU support which also makes it unlikely + * that this page is used. This bug was introduced well after type1 v2 + * support was introduced, so we shouldn't need to test for v1. A fix + * is queued for kernel v5.0 so this workaround can be removed once + * affected kernels are sufficiently deprecated. + */ + if (errno == EINVAL && unmap.size && !(unmap.iova + unmap.size) && + container->iommu_type == VFIO_TYPE1v2_IOMMU) { + trace_vfio_dma_unmap_overflow_workaround(); + unmap.size -= 1ULL << ctz64(container->pgsizes); + continue; + } + error_report("VFIO_UNMAP_DMA failed: %s", strerror(errno)); + return -errno; + } + + if (need_dirty_sync) { + ret = vfio_get_dirty_bitmap(container, iova, size, + iotlb->translated_addr); + if (ret) { + return ret; + } + } + + return 0; +} + +int vfio_dma_map(VFIOContainer *container, hwaddr iova, + ram_addr_t size, void *vaddr, bool readonly) +{ + struct vfio_iommu_type1_dma_map map = { + .argsz = sizeof(map), + .flags = VFIO_DMA_MAP_FLAG_READ, + .vaddr = (__u64)(uintptr_t)vaddr, + .iova = iova, + .size = size, + }; + + if (!readonly) { + map.flags |= VFIO_DMA_MAP_FLAG_WRITE; + } + + /* + * Try the mapping, if it fails with EBUSY, unmap the region and try + * again. This shouldn't be necessary, but we sometimes see it in + * the VGA ROM space. + */ + if (ioctl(container->fd, VFIO_IOMMU_MAP_DMA, &map) == 0 || + (errno == EBUSY && vfio_dma_unmap(container, iova, size, NULL) == 0 && + ioctl(container->fd, VFIO_IOMMU_MAP_DMA, &map) == 0)) { + return 0; + } + + error_report("VFIO_MAP_DMA failed: %s", strerror(errno)); + return -errno; +} + +int vfio_container_add_section_window(VFIOContainer *container, + MemoryRegionSection *section, + Error **errp) +{ + VFIOHostDMAWindow *hostwin; + hwaddr pgsize = 0; + int ret; + + if (container->iommu_type != VFIO_SPAPR_TCE_v2_IOMMU) { + return 0; + } + + /* For now intersections are not allowed, we may relax this later */ + QLIST_FOREACH(hostwin, &container->hostwin_list, hostwin_next) { + if (ranges_overlap(hostwin->min_iova, + hostwin->max_iova - hostwin->min_iova + 1, + section->offset_within_address_space, + int128_get64(section->size))) { + error_setg(errp, + "region [0x%"PRIx64",0x%"PRIx64"] overlaps with existing" + "host DMA window [0x%"PRIx64",0x%"PRIx64"]", + section->offset_within_address_space, + section->offset_within_address_space + + int128_get64(section->size) - 1, + hostwin->min_iova, hostwin->max_iova); + return -EINVAL; + } + } + + ret = vfio_spapr_create_window(container, section, &pgsize); + if (ret) { + error_setg_errno(errp, -ret, "Failed to create SPAPR window"); + return ret; + } + + vfio_host_win_add(container, section->offset_within_address_space, + section->offset_within_address_space + + int128_get64(section->size) - 1, pgsize); +#ifdef CONFIG_KVM + if (kvm_enabled()) { + VFIOGroup *group; + IOMMUMemoryRegion *iommu_mr = IOMMU_MEMORY_REGION(section->mr); + struct kvm_vfio_spapr_tce param; + struct kvm_device_attr attr = { + .group = KVM_DEV_VFIO_GROUP, + .attr = KVM_DEV_VFIO_GROUP_SET_SPAPR_TCE, + .addr = (uint64_t)(unsigned long)¶m, + }; + + if (!memory_region_iommu_get_attr(iommu_mr, IOMMU_ATTR_SPAPR_TCE_FD, + ¶m.tablefd)) { + QLIST_FOREACH(group, &container->group_list, container_next) { + param.groupfd = group->fd; + if (ioctl(vfio_kvm_device_fd, KVM_SET_DEVICE_ATTR, &attr)) { + error_setg_errno(errp, errno, + "vfio: failed GROUP_SET_SPAPR_TCE for " + "KVM VFIO device %d and group fd %d", + param.tablefd, param.groupfd); + return -errno; + } + trace_vfio_spapr_group_attach(param.groupfd, param.tablefd); + } + } + } +#endif + return 0; +} + +void vfio_container_del_section_window(VFIOContainer *container, + MemoryRegionSection *section) +{ + if (container->iommu_type != VFIO_SPAPR_TCE_v2_IOMMU) { + return; + } + + vfio_spapr_remove_window(container, + section->offset_within_address_space); + if (vfio_host_win_del(container, + section->offset_within_address_space, + section->offset_within_address_space + + int128_get64(section->size) - 1) < 0) { + hw_error("%s: Cannot delete missing window at %"HWADDR_PRIx, + __func__, section->offset_within_address_space); + } +} + +int vfio_set_dirty_page_tracking(VFIOContainer *container, bool start) +{ + int ret; + struct vfio_iommu_type1_dirty_bitmap dirty = { + .argsz = sizeof(dirty), + }; + + if (!container->dirty_pages_supported) { + return 0; + } + + if (start) { + dirty.flags = VFIO_IOMMU_DIRTY_PAGES_FLAG_START; + } else { + dirty.flags = VFIO_IOMMU_DIRTY_PAGES_FLAG_STOP; + } + + ret = ioctl(container->fd, VFIO_IOMMU_DIRTY_PAGES, &dirty); + if (ret) { + ret = -errno; + error_report("Failed to set dirty tracking flag 0x%x errno: %d", + dirty.flags, errno); + } + + return ret; +} + +int vfio_query_dirty_bitmap(VFIOContainer *container, VFIOBitmap *vbmap, + hwaddr iova, hwaddr size) +{ + struct vfio_iommu_type1_dirty_bitmap *dbitmap; + struct vfio_iommu_type1_dirty_bitmap_get *range; + int ret; + + dbitmap = g_malloc0(sizeof(*dbitmap) + sizeof(*range)); + + dbitmap->argsz = sizeof(*dbitmap) + sizeof(*range); + dbitmap->flags = VFIO_IOMMU_DIRTY_PAGES_FLAG_GET_BITMAP; + range = (struct vfio_iommu_type1_dirty_bitmap_get *)&dbitmap->data; + range->iova = iova; + range->size = size; + + /* + * cpu_physical_memory_set_dirty_lebitmap() supports pages in bitmap of + * qemu_real_host_page_size to mark those dirty. Hence set bitmap's pgsize + * to qemu_real_host_page_size. + */ + range->bitmap.pgsize = qemu_real_host_page_size(); + range->bitmap.size = vbmap->size; + range->bitmap.data = (__u64 *)vbmap->bitmap; + + ret = ioctl(container->fd, VFIO_IOMMU_DIRTY_PAGES, dbitmap); + if (ret) { + ret = -errno; + error_report("Failed to get dirty bitmap for iova: 0x%"PRIx64 + " size: 0x%"PRIx64" err: %d", (uint64_t)range->iova, + (uint64_t)range->size, errno); + } + + g_free(dbitmap); + + return ret; +} + +static void vfio_listener_release(VFIOContainer *container) +{ + memory_listener_unregister(&container->listener); + if (container->iommu_type == VFIO_SPAPR_TCE_v2_IOMMU) { + memory_listener_unregister(&container->prereg_listener); + } +} + +static struct vfio_info_cap_header * +vfio_get_iommu_type1_info_cap(struct vfio_iommu_type1_info *info, uint16_t id) +{ + if (!(info->flags & VFIO_IOMMU_INFO_CAPS)) { + return NULL; + } + + return vfio_get_cap((void *)info, info->cap_offset, id); +} + +bool vfio_get_info_dma_avail(struct vfio_iommu_type1_info *info, + unsigned int *avail) +{ + struct vfio_info_cap_header *hdr; + struct vfio_iommu_type1_info_dma_avail *cap; + + /* If the capability cannot be found, assume no DMA limiting */ + hdr = vfio_get_iommu_type1_info_cap(info, + VFIO_IOMMU_TYPE1_INFO_DMA_AVAIL); + if (hdr == NULL) { + return false; + } + + if (avail != NULL) { + cap = (void *) hdr; + *avail = cap->avail; + } + + return true; +} + +static void vfio_kvm_device_add_group(VFIOGroup *group) +{ + Error *err = NULL; + + if (vfio_kvm_device_add_fd(group->fd, &err)) { + error_reportf_err(err, "group ID %d: ", group->groupid); + } +} + +static void vfio_kvm_device_del_group(VFIOGroup *group) +{ + Error *err = NULL; + + if (vfio_kvm_device_del_fd(group->fd, &err)) { + error_reportf_err(err, "group ID %d: ", group->groupid); + } +} + +/* + * vfio_get_iommu_type - selects the richest iommu_type (v2 first) + */ +static int vfio_get_iommu_type(VFIOContainer *container, + Error **errp) +{ + int iommu_types[] = { VFIO_TYPE1v2_IOMMU, VFIO_TYPE1_IOMMU, + VFIO_SPAPR_TCE_v2_IOMMU, VFIO_SPAPR_TCE_IOMMU }; + int i; + + for (i = 0; i < ARRAY_SIZE(iommu_types); i++) { + if (ioctl(container->fd, VFIO_CHECK_EXTENSION, iommu_types[i])) { + return iommu_types[i]; + } + } + error_setg(errp, "No available IOMMU models"); + return -EINVAL; +} + +static int vfio_init_container(VFIOContainer *container, int group_fd, + Error **errp) +{ + int iommu_type, ret; + + iommu_type = vfio_get_iommu_type(container, errp); + if (iommu_type < 0) { + return iommu_type; + } + + ret = ioctl(group_fd, VFIO_GROUP_SET_CONTAINER, &container->fd); + if (ret) { + error_setg_errno(errp, errno, "Failed to set group container"); + return -errno; + } + + while (ioctl(container->fd, VFIO_SET_IOMMU, iommu_type)) { + if (iommu_type == VFIO_SPAPR_TCE_v2_IOMMU) { + /* + * On sPAPR, despite the IOMMU subdriver always advertises v1 and + * v2, the running platform may not support v2 and there is no + * way to guess it until an IOMMU group gets added to the container. + * So in case it fails with v2, try v1 as a fallback. + */ + iommu_type = VFIO_SPAPR_TCE_IOMMU; + continue; + } + error_setg_errno(errp, errno, "Failed to set iommu for container"); + return -errno; + } + + container->iommu_type = iommu_type; + return 0; +} + +static int vfio_get_iommu_info(VFIOContainer *container, + struct vfio_iommu_type1_info **info) +{ + + size_t argsz = sizeof(struct vfio_iommu_type1_info); + + *info = g_new0(struct vfio_iommu_type1_info, 1); +again: + (*info)->argsz = argsz; + + if (ioctl(container->fd, VFIO_IOMMU_GET_INFO, *info)) { + g_free(*info); + *info = NULL; + return -errno; + } + + if (((*info)->argsz > argsz)) { + argsz = (*info)->argsz; + *info = g_realloc(*info, argsz); + goto again; + } + + return 0; +} + +static struct vfio_info_cap_header * +vfio_get_iommu_info_cap(struct vfio_iommu_type1_info *info, uint16_t id) +{ + struct vfio_info_cap_header *hdr; + void *ptr = info; + + if (!(info->flags & VFIO_IOMMU_INFO_CAPS)) { + return NULL; + } + + for (hdr = ptr + info->cap_offset; hdr != ptr; hdr = ptr + hdr->next) { + if (hdr->id == id) { + return hdr; + } + } + + return NULL; +} + +static void vfio_get_iommu_info_migration(VFIOContainer *container, + struct vfio_iommu_type1_info *info) +{ + struct vfio_info_cap_header *hdr; + struct vfio_iommu_type1_info_cap_migration *cap_mig; + + hdr = vfio_get_iommu_info_cap(info, VFIO_IOMMU_TYPE1_INFO_CAP_MIGRATION); + if (!hdr) { + return; + } + + cap_mig = container_of(hdr, struct vfio_iommu_type1_info_cap_migration, + header); + + /* + * cpu_physical_memory_set_dirty_lebitmap() supports pages in bitmap of + * qemu_real_host_page_size to mark those dirty. + */ + if (cap_mig->pgsize_bitmap & qemu_real_host_page_size()) { + container->dirty_pages_supported = true; + container->max_dirty_bitmap_size = cap_mig->max_dirty_bitmap_size; + container->dirty_pgsizes = cap_mig->pgsize_bitmap; + } +} + +static int vfio_connect_container(VFIOGroup *group, AddressSpace *as, + Error **errp) +{ + VFIOContainer *container; + int ret, fd; + VFIOAddressSpace *space; + + space = vfio_get_address_space(as); + + /* + * VFIO is currently incompatible with discarding of RAM insofar as the + * madvise to purge (zap) the page from QEMU's address space does not + * interact with the memory API and therefore leaves stale virtual to + * physical mappings in the IOMMU if the page was previously pinned. We + * therefore set discarding broken for each group added to a container, + * whether the container is used individually or shared. This provides + * us with options to allow devices within a group to opt-in and allow + * discarding, so long as it is done consistently for a group (for instance + * if the device is an mdev device where it is known that the host vendor + * driver will never pin pages outside of the working set of the guest + * driver, which would thus not be discarding candidates). + * + * The first opportunity to induce pinning occurs here where we attempt to + * attach the group to existing containers within the AddressSpace. If any + * pages are already zapped from the virtual address space, such as from + * previous discards, new pinning will cause valid mappings to be + * re-established. Likewise, when the overall MemoryListener for a new + * container is registered, a replay of mappings within the AddressSpace + * will occur, re-establishing any previously zapped pages as well. + * + * Especially virtio-balloon is currently only prevented from discarding + * new memory, it will not yet set ram_block_discard_set_required() and + * therefore, neither stops us here or deals with the sudden memory + * consumption of inflated memory. + * + * We do support discarding of memory coordinated via the RamDiscardManager + * with some IOMMU types. vfio_ram_block_discard_disable() handles the + * details once we know which type of IOMMU we are using. + */ + + QLIST_FOREACH(container, &space->containers, next) { + if (!ioctl(group->fd, VFIO_GROUP_SET_CONTAINER, &container->fd)) { + ret = vfio_ram_block_discard_disable(container, true); + if (ret) { + error_setg_errno(errp, -ret, + "Cannot set discarding of RAM broken"); + if (ioctl(group->fd, VFIO_GROUP_UNSET_CONTAINER, + &container->fd)) { + error_report("vfio: error disconnecting group %d from" + " container", group->groupid); + } + return ret; + } + group->container = container; + QLIST_INSERT_HEAD(&container->group_list, group, container_next); + vfio_kvm_device_add_group(group); + return 0; + } + } + + fd = qemu_open_old("/dev/vfio/vfio", O_RDWR); + if (fd < 0) { + error_setg_errno(errp, errno, "failed to open /dev/vfio/vfio"); + ret = -errno; + goto put_space_exit; + } + + ret = ioctl(fd, VFIO_GET_API_VERSION); + if (ret != VFIO_API_VERSION) { + error_setg(errp, "supported vfio version: %d, " + "reported version: %d", VFIO_API_VERSION, ret); + ret = -EINVAL; + goto close_fd_exit; + } + + container = g_malloc0(sizeof(*container)); + container->space = space; + container->fd = fd; + container->error = NULL; + container->dirty_pages_supported = false; + container->dma_max_mappings = 0; + QLIST_INIT(&container->giommu_list); + QLIST_INIT(&container->hostwin_list); + QLIST_INIT(&container->vrdl_list); + + ret = vfio_init_container(container, group->fd, errp); + if (ret) { + goto free_container_exit; + } + + ret = vfio_ram_block_discard_disable(container, true); + if (ret) { + error_setg_errno(errp, -ret, "Cannot set discarding of RAM broken"); + goto free_container_exit; + } + + switch (container->iommu_type) { + case VFIO_TYPE1v2_IOMMU: + case VFIO_TYPE1_IOMMU: + { + struct vfio_iommu_type1_info *info; + + ret = vfio_get_iommu_info(container, &info); + if (ret) { + error_setg_errno(errp, -ret, "Failed to get VFIO IOMMU info"); + goto enable_discards_exit; + } + + if (info->flags & VFIO_IOMMU_INFO_PGSIZES) { + container->pgsizes = info->iova_pgsizes; + } else { + container->pgsizes = qemu_real_host_page_size(); + } + + if (!vfio_get_info_dma_avail(info, &container->dma_max_mappings)) { + container->dma_max_mappings = 65535; + } + vfio_get_iommu_info_migration(container, info); + g_free(info); + + /* + * FIXME: We should parse VFIO_IOMMU_TYPE1_INFO_CAP_IOVA_RANGE + * information to get the actual window extent rather than assume + * a 64-bit IOVA address space. + */ + vfio_host_win_add(container, 0, (hwaddr)-1, container->pgsizes); + + break; + } + case VFIO_SPAPR_TCE_v2_IOMMU: + case VFIO_SPAPR_TCE_IOMMU: + { + struct vfio_iommu_spapr_tce_info info; + bool v2 = container->iommu_type == VFIO_SPAPR_TCE_v2_IOMMU; + + /* + * The host kernel code implementing VFIO_IOMMU_DISABLE is called + * when container fd is closed so we do not call it explicitly + * in this file. + */ + if (!v2) { + ret = ioctl(fd, VFIO_IOMMU_ENABLE); + if (ret) { + error_setg_errno(errp, errno, "failed to enable container"); + ret = -errno; + goto enable_discards_exit; + } + } else { + container->prereg_listener = vfio_prereg_listener; + + memory_listener_register(&container->prereg_listener, + &address_space_memory); + if (container->error) { + memory_listener_unregister(&container->prereg_listener); + ret = -1; + error_propagate_prepend(errp, container->error, + "RAM memory listener initialization failed: "); + goto enable_discards_exit; + } + } + + info.argsz = sizeof(info); + ret = ioctl(fd, VFIO_IOMMU_SPAPR_TCE_GET_INFO, &info); + if (ret) { + error_setg_errno(errp, errno, + "VFIO_IOMMU_SPAPR_TCE_GET_INFO failed"); + ret = -errno; + if (v2) { + memory_listener_unregister(&container->prereg_listener); + } + goto enable_discards_exit; + } + + if (v2) { + container->pgsizes = info.ddw.pgsizes; + /* + * 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. + */ + ret = vfio_spapr_remove_window(container, info.dma32_window_start); + if (ret) { + error_setg_errno(errp, -ret, + "failed to remove existing window"); + goto enable_discards_exit; + } + } else { + /* The default table uses 4K pages */ + container->pgsizes = 0x1000; + vfio_host_win_add(container, info.dma32_window_start, + info.dma32_window_start + + info.dma32_window_size - 1, + 0x1000); + } + } + } + + vfio_kvm_device_add_group(group); + + QLIST_INIT(&container->group_list); + QLIST_INSERT_HEAD(&space->containers, container, next); + + group->container = container; + QLIST_INSERT_HEAD(&container->group_list, group, container_next); + + container->listener = vfio_memory_listener; + + memory_listener_register(&container->listener, container->space->as); + + if (container->error) { + ret = -1; + error_propagate_prepend(errp, container->error, + "memory listener initialization failed: "); + goto listener_release_exit; + } + + container->initialized = true; + + return 0; +listener_release_exit: + QLIST_REMOVE(group, container_next); + QLIST_REMOVE(container, next); + vfio_kvm_device_del_group(group); + vfio_listener_release(container); + +enable_discards_exit: + vfio_ram_block_discard_disable(container, false); + +free_container_exit: + g_free(container); + +close_fd_exit: + close(fd); + +put_space_exit: + vfio_put_address_space(space); + + return ret; +} + +static void vfio_disconnect_container(VFIOGroup *group) +{ + VFIOContainer *container = group->container; + + QLIST_REMOVE(group, container_next); + group->container = NULL; + + /* + * Explicitly release the listener first before unset container, + * since unset may destroy the backend container if it's the last + * group. + */ + if (QLIST_EMPTY(&container->group_list)) { + vfio_listener_release(container); + } + + if (ioctl(group->fd, VFIO_GROUP_UNSET_CONTAINER, &container->fd)) { + error_report("vfio: error disconnecting group %d from container", + group->groupid); + } + + if (QLIST_EMPTY(&container->group_list)) { + VFIOAddressSpace *space = container->space; + VFIOGuestIOMMU *giommu, *tmp; + VFIOHostDMAWindow *hostwin, *next; + + QLIST_REMOVE(container, next); + + QLIST_FOREACH_SAFE(giommu, &container->giommu_list, giommu_next, tmp) { + memory_region_unregister_iommu_notifier( + MEMORY_REGION(giommu->iommu_mr), &giommu->n); + QLIST_REMOVE(giommu, giommu_next); + g_free(giommu); + } + + QLIST_FOREACH_SAFE(hostwin, &container->hostwin_list, hostwin_next, + next) { + QLIST_REMOVE(hostwin, hostwin_next); + g_free(hostwin); + } + + trace_vfio_disconnect_container(container->fd); + close(container->fd); + g_free(container); + + vfio_put_address_space(space); + } +} + +static VFIOGroup *vfio_get_group(int groupid, AddressSpace *as, Error **errp) +{ + VFIOGroup *group; + char path[32]; + struct vfio_group_status status = { .argsz = sizeof(status) }; + + QLIST_FOREACH(group, &vfio_group_list, next) { + if (group->groupid == groupid) { + /* Found it. Now is it already in the right context? */ + if (group->container->space->as == as) { + return group; + } else { + error_setg(errp, "group %d used in multiple address spaces", + group->groupid); + return NULL; + } + } + } + + group = g_malloc0(sizeof(*group)); + + snprintf(path, sizeof(path), "/dev/vfio/%d", groupid); + group->fd = qemu_open_old(path, O_RDWR); + if (group->fd < 0) { + error_setg_errno(errp, errno, "failed to open %s", path); + goto free_group_exit; + } + + if (ioctl(group->fd, VFIO_GROUP_GET_STATUS, &status)) { + error_setg_errno(errp, errno, "failed to get group %d status", groupid); + goto close_fd_exit; + } + + if (!(status.flags & VFIO_GROUP_FLAGS_VIABLE)) { + error_setg(errp, "group %d is not viable", groupid); + error_append_hint(errp, + "Please ensure all devices within the iommu_group " + "are bound to their vfio bus driver.\n"); + goto close_fd_exit; + } + + group->groupid = groupid; + QLIST_INIT(&group->device_list); + + if (vfio_connect_container(group, as, errp)) { + error_prepend(errp, "failed to setup container for group %d: ", + groupid); + goto close_fd_exit; + } + + QLIST_INSERT_HEAD(&vfio_group_list, group, next); + + return group; + +close_fd_exit: + close(group->fd); + +free_group_exit: + g_free(group); + + return NULL; +} + +static void vfio_put_group(VFIOGroup *group) +{ + if (!group || !QLIST_EMPTY(&group->device_list)) { + return; + } + + if (!group->ram_block_discard_allowed) { + vfio_ram_block_discard_disable(group->container, false); + } + vfio_kvm_device_del_group(group); + vfio_disconnect_container(group); + QLIST_REMOVE(group, next); + trace_vfio_put_group(group->fd); + close(group->fd); + g_free(group); +} + +static int vfio_get_device(VFIOGroup *group, const char *name, + VFIODevice *vbasedev, Error **errp) +{ + g_autofree struct vfio_device_info *info = NULL; + int fd; + + fd = ioctl(group->fd, VFIO_GROUP_GET_DEVICE_FD, name); + if (fd < 0) { + error_setg_errno(errp, errno, "error getting device from group %d", + group->groupid); + error_append_hint(errp, + "Verify all devices in group %d are bound to vfio-<bus> " + "or pci-stub and not already in use\n", group->groupid); + return fd; + } + + info = vfio_get_device_info(fd); + if (!info) { + error_setg_errno(errp, errno, "error getting device info"); + close(fd); + return -1; + } + + /* + * Set discarding of RAM as not broken for this group if the driver knows + * the device operates compatibly with discarding. Setting must be + * consistent per group, but since compatibility is really only possible + * with mdev currently, we expect singleton groups. + */ + if (vbasedev->ram_block_discard_allowed != + group->ram_block_discard_allowed) { + if (!QLIST_EMPTY(&group->device_list)) { + error_setg(errp, "Inconsistent setting of support for discarding " + "RAM (e.g., balloon) within group"); + close(fd); + return -1; + } + + if (!group->ram_block_discard_allowed) { + group->ram_block_discard_allowed = true; + vfio_ram_block_discard_disable(group->container, false); + } + } + + vbasedev->fd = fd; + vbasedev->group = group; + QLIST_INSERT_HEAD(&group->device_list, vbasedev, next); + + vbasedev->num_irqs = info->num_irqs; + vbasedev->num_regions = info->num_regions; + vbasedev->flags = info->flags; + + trace_vfio_get_device(name, info->flags, info->num_regions, info->num_irqs); + + vbasedev->reset_works = !!(info->flags & VFIO_DEVICE_FLAGS_RESET); + + return 0; +} + +static void vfio_put_base_device(VFIODevice *vbasedev) +{ + if (!vbasedev->group) { + return; + } + QLIST_REMOVE(vbasedev, next); + vbasedev->group = NULL; + trace_vfio_put_base_device(vbasedev->fd); + close(vbasedev->fd); +} + +/* + * Interfaces for IBM EEH (Enhanced Error Handling) + */ +static bool vfio_eeh_container_ok(VFIOContainer *container) +{ + /* + * As of 2016-03-04 (linux-4.5) the host kernel EEH/VFIO + * implementation is broken if there are multiple groups in a + * container. The hardware works in units of Partitionable + * Endpoints (== IOMMU groups) and the EEH operations naively + * iterate across all groups in the container, without any logic + * to make sure the groups have their state synchronized. For + * certain operations (ENABLE) that might be ok, until an error + * occurs, but for others (GET_STATE) it's clearly broken. + */ + + /* + * XXX Once fixed kernels exist, test for them here + */ + + if (QLIST_EMPTY(&container->group_list)) { + return false; + } + + if (QLIST_NEXT(QLIST_FIRST(&container->group_list), container_next)) { + return false; + } + + return true; +} + +static int vfio_eeh_container_op(VFIOContainer *container, uint32_t op) +{ + struct vfio_eeh_pe_op pe_op = { + .argsz = sizeof(pe_op), + .op = op, + }; + int ret; + + if (!vfio_eeh_container_ok(container)) { + error_report("vfio/eeh: EEH_PE_OP 0x%x: " + "kernel requires a container with exactly one group", op); + return -EPERM; + } + + ret = ioctl(container->fd, VFIO_EEH_PE_OP, &pe_op); + if (ret < 0) { + error_report("vfio/eeh: EEH_PE_OP 0x%x failed: %m", op); + return -errno; + } + + return ret; +} + +static VFIOContainer *vfio_eeh_as_container(AddressSpace *as) +{ + VFIOAddressSpace *space = vfio_get_address_space(as); + VFIOContainer *container = NULL; + + if (QLIST_EMPTY(&space->containers)) { + /* No containers to act on */ + goto out; + } + + container = QLIST_FIRST(&space->containers); + + if (QLIST_NEXT(container, next)) { + /* + * We don't yet have logic to synchronize EEH state across + * multiple containers + */ + container = NULL; + goto out; + } + +out: + vfio_put_address_space(space); + return container; +} + +bool vfio_eeh_as_ok(AddressSpace *as) +{ + VFIOContainer *container = vfio_eeh_as_container(as); + + return (container != NULL) && vfio_eeh_container_ok(container); +} + +int vfio_eeh_as_op(AddressSpace *as, uint32_t op) +{ + VFIOContainer *container = vfio_eeh_as_container(as); + + if (!container) { + return -ENODEV; + } + return vfio_eeh_container_op(container, op); +} + +static int vfio_device_groupid(VFIODevice *vbasedev, Error **errp) +{ + char *tmp, group_path[PATH_MAX], *group_name; + int ret, groupid; + ssize_t len; + + tmp = g_strdup_printf("%s/iommu_group", vbasedev->sysfsdev); + len = readlink(tmp, group_path, sizeof(group_path)); + g_free(tmp); + + if (len <= 0 || len >= sizeof(group_path)) { + ret = len < 0 ? -errno : -ENAMETOOLONG; + error_setg_errno(errp, -ret, "no iommu_group found"); + return ret; + } + + group_path[len] = 0; + + group_name = basename(group_path); + if (sscanf(group_name, "%d", &groupid) != 1) { + error_setg_errno(errp, errno, "failed to read %s", group_path); + return -errno; + } + return groupid; +} + +/* + * vfio_attach_device: attach a device to a security context + * @name and @vbasedev->name are likely to be different depending + * on the type of the device, hence the need for passing @name + */ +int vfio_attach_device(char *name, VFIODevice *vbasedev, + AddressSpace *as, Error **errp) +{ + int groupid = vfio_device_groupid(vbasedev, errp); + VFIODevice *vbasedev_iter; + VFIOGroup *group; + VFIOContainer *container; + int ret; + + if (groupid < 0) { + return groupid; + } + + trace_vfio_attach_device(vbasedev->name, groupid); + + group = vfio_get_group(groupid, as, errp); + if (!group) { + return -ENOENT; + } + + QLIST_FOREACH(vbasedev_iter, &group->device_list, next) { + if (strcmp(vbasedev_iter->name, vbasedev->name) == 0) { + error_setg(errp, "device is already attached"); + vfio_put_group(group); + return -EBUSY; + } + } + ret = vfio_get_device(group, name, vbasedev, errp); + if (ret) { + vfio_put_group(group); + return ret; + } + + container = group->container; + vbasedev->container = container; + QLIST_INSERT_HEAD(&container->device_list, vbasedev, container_next); + QLIST_INSERT_HEAD(&vfio_device_list, vbasedev, global_next); + + return ret; +} + +void vfio_detach_device(VFIODevice *vbasedev) +{ + VFIOGroup *group = vbasedev->group; + + if (!vbasedev->container) { + return; + } + + QLIST_REMOVE(vbasedev, global_next); + QLIST_REMOVE(vbasedev, container_next); + vbasedev->container = NULL; + trace_vfio_detach_device(vbasedev->name, group->groupid); + vfio_put_base_device(vbasedev); + vfio_put_group(group); +} |