1 // SPDX-License-Identifier: GPL-2.0-only
3 * VFIO: IOMMU DMA mapping support for Type1 IOMMU
5 * Copyright (C) 2012 Red Hat, Inc. All rights reserved.
8 * Derived from original vfio:
9 * Copyright 2010 Cisco Systems, Inc. All rights reserved.
12 * We arbitrarily define a Type1 IOMMU as one matching the below code.
13 * It could be called the x86 IOMMU as it's designed for AMD-Vi & Intel
14 * VT-d, but that makes it harder to re-use as theoretically anyone
15 * implementing a similar IOMMU could make use of this. We expect the
16 * IOMMU to support the IOMMU API and have few to no restrictions around
17 * the IOVA range that can be mapped. The Type1 IOMMU is currently
18 * optimized for relatively static mappings of a userspace process with
19 * userspace pages pinned into memory. We also assume devices and IOMMU
20 * domains are PCI based as the IOMMU API is still centered around a
21 * device/bus interface rather than a group interface.
24 #include <linux/compat.h>
25 #include <linux/device.h>
27 #include <linux/highmem.h>
28 #include <linux/iommu.h>
29 #include <linux/module.h>
31 #include <linux/kthread.h>
32 #include <linux/rbtree.h>
33 #include <linux/sched/signal.h>
34 #include <linux/sched/mm.h>
35 #include <linux/slab.h>
36 #include <linux/uaccess.h>
37 #include <linux/vfio.h>
38 #include <linux/workqueue.h>
39 #include <linux/notifier.h>
42 #define DRIVER_VERSION "0.2"
44 #define DRIVER_DESC "Type1 IOMMU driver for VFIO"
46 static bool allow_unsafe_interrupts;
47 module_param_named(allow_unsafe_interrupts,
48 allow_unsafe_interrupts, bool, S_IRUGO | S_IWUSR);
49 MODULE_PARM_DESC(allow_unsafe_interrupts,
50 "Enable VFIO IOMMU support for on platforms without interrupt remapping support.");
52 static bool disable_hugepages;
53 module_param_named(disable_hugepages,
54 disable_hugepages, bool, S_IRUGO | S_IWUSR);
55 MODULE_PARM_DESC(disable_hugepages,
56 "Disable VFIO IOMMU support for IOMMU hugepages.");
58 static unsigned int dma_entry_limit __read_mostly = U16_MAX;
59 module_param_named(dma_entry_limit, dma_entry_limit, uint, 0644);
60 MODULE_PARM_DESC(dma_entry_limit,
61 "Maximum number of user DMA mappings per container (65535).");
64 struct list_head domain_list;
65 struct list_head iova_list;
67 struct rb_root dma_list;
68 struct list_head device_list;
69 struct mutex device_list_lock;
70 unsigned int dma_avail;
71 unsigned int vaddr_invalid_count;
72 uint64_t pgsize_bitmap;
73 uint64_t num_non_pinned_groups;
76 bool dirty_page_tracking;
77 struct list_head emulated_iommu_groups;
81 struct iommu_domain *domain;
82 struct list_head next;
83 struct list_head group_list;
84 bool fgsp : 1; /* Fine-grained super pages */
85 bool enforce_cache_coherency : 1;
90 dma_addr_t iova; /* Device address */
91 unsigned long vaddr; /* Process virtual addr */
92 size_t size; /* Map size (bytes) */
93 int prot; /* IOMMU_READ/WRITE */
95 bool lock_cap; /* capable(CAP_IPC_LOCK) */
97 struct task_struct *task;
98 struct rb_root pfn_list; /* Ex-user pinned pfn list */
99 unsigned long *bitmap;
100 struct mm_struct *mm;
105 struct page **pages; /* for pin_user_pages_remote */
106 struct page *fallback_page; /* if pages alloc fails */
107 int capacity; /* length of pages array */
108 int size; /* of batch currently */
109 int offset; /* of next entry in pages */
112 struct vfio_iommu_group {
113 struct iommu_group *iommu_group;
114 struct list_head next;
115 bool pinned_page_dirty_scope;
119 struct list_head list;
125 * Guest RAM pinning working set or DMA target
129 dma_addr_t iova; /* Device address */
130 unsigned long pfn; /* Host pfn */
131 unsigned int ref_count;
134 struct vfio_regions {
135 struct list_head list;
141 #define DIRTY_BITMAP_BYTES(n) (ALIGN(n, BITS_PER_TYPE(u64)) / BITS_PER_BYTE)
144 * Input argument of number of bits to bitmap_set() is unsigned integer, which
145 * further casts to signed integer for unaligned multi-bit operation,
147 * Then maximum bitmap size supported is 2^31 bits divided by 2^3 bits/byte,
148 * that is 2^28 (256 MB) which maps to 2^31 * 2^12 = 2^43 (8TB) on 4K page
151 #define DIRTY_BITMAP_PAGES_MAX ((u64)INT_MAX)
152 #define DIRTY_BITMAP_SIZE_MAX DIRTY_BITMAP_BYTES(DIRTY_BITMAP_PAGES_MAX)
154 static int put_pfn(unsigned long pfn, int prot);
156 static struct vfio_iommu_group*
157 vfio_iommu_find_iommu_group(struct vfio_iommu *iommu,
158 struct iommu_group *iommu_group);
161 * This code handles mapping and unmapping of user data buffers
162 * into DMA'ble space using the IOMMU
165 static struct vfio_dma *vfio_find_dma(struct vfio_iommu *iommu,
166 dma_addr_t start, size_t size)
168 struct rb_node *node = iommu->dma_list.rb_node;
171 struct vfio_dma *dma = rb_entry(node, struct vfio_dma, node);
173 if (start + size <= dma->iova)
174 node = node->rb_left;
175 else if (start >= dma->iova + dma->size)
176 node = node->rb_right;
184 static struct rb_node *vfio_find_dma_first_node(struct vfio_iommu *iommu,
185 dma_addr_t start, u64 size)
187 struct rb_node *res = NULL;
188 struct rb_node *node = iommu->dma_list.rb_node;
189 struct vfio_dma *dma_res = NULL;
192 struct vfio_dma *dma = rb_entry(node, struct vfio_dma, node);
194 if (start < dma->iova + dma->size) {
197 if (start >= dma->iova)
199 node = node->rb_left;
201 node = node->rb_right;
204 if (res && size && dma_res->iova >= start + size)
209 static void vfio_link_dma(struct vfio_iommu *iommu, struct vfio_dma *new)
211 struct rb_node **link = &iommu->dma_list.rb_node, *parent = NULL;
212 struct vfio_dma *dma;
216 dma = rb_entry(parent, struct vfio_dma, node);
218 if (new->iova + new->size <= dma->iova)
219 link = &(*link)->rb_left;
221 link = &(*link)->rb_right;
224 rb_link_node(&new->node, parent, link);
225 rb_insert_color(&new->node, &iommu->dma_list);
228 static void vfio_unlink_dma(struct vfio_iommu *iommu, struct vfio_dma *old)
230 rb_erase(&old->node, &iommu->dma_list);
234 static int vfio_dma_bitmap_alloc(struct vfio_dma *dma, size_t pgsize)
236 uint64_t npages = dma->size / pgsize;
238 if (npages > DIRTY_BITMAP_PAGES_MAX)
242 * Allocate extra 64 bits that are used to calculate shift required for
243 * bitmap_shift_left() to manipulate and club unaligned number of pages
244 * in adjacent vfio_dma ranges.
246 dma->bitmap = kvzalloc(DIRTY_BITMAP_BYTES(npages) + sizeof(u64),
254 static void vfio_dma_bitmap_free(struct vfio_dma *dma)
260 static void vfio_dma_populate_bitmap(struct vfio_dma *dma, size_t pgsize)
263 unsigned long pgshift = __ffs(pgsize);
265 for (p = rb_first(&dma->pfn_list); p; p = rb_next(p)) {
266 struct vfio_pfn *vpfn = rb_entry(p, struct vfio_pfn, node);
268 bitmap_set(dma->bitmap, (vpfn->iova - dma->iova) >> pgshift, 1);
272 static void vfio_iommu_populate_bitmap_full(struct vfio_iommu *iommu)
275 unsigned long pgshift = __ffs(iommu->pgsize_bitmap);
277 for (n = rb_first(&iommu->dma_list); n; n = rb_next(n)) {
278 struct vfio_dma *dma = rb_entry(n, struct vfio_dma, node);
280 bitmap_set(dma->bitmap, 0, dma->size >> pgshift);
284 static int vfio_dma_bitmap_alloc_all(struct vfio_iommu *iommu, size_t pgsize)
288 for (n = rb_first(&iommu->dma_list); n; n = rb_next(n)) {
289 struct vfio_dma *dma = rb_entry(n, struct vfio_dma, node);
292 ret = vfio_dma_bitmap_alloc(dma, pgsize);
296 for (p = rb_prev(n); p; p = rb_prev(p)) {
297 struct vfio_dma *dma = rb_entry(n,
298 struct vfio_dma, node);
300 vfio_dma_bitmap_free(dma);
304 vfio_dma_populate_bitmap(dma, pgsize);
309 static void vfio_dma_bitmap_free_all(struct vfio_iommu *iommu)
313 for (n = rb_first(&iommu->dma_list); n; n = rb_next(n)) {
314 struct vfio_dma *dma = rb_entry(n, struct vfio_dma, node);
316 vfio_dma_bitmap_free(dma);
321 * Helper Functions for host iova-pfn list
323 static struct vfio_pfn *vfio_find_vpfn(struct vfio_dma *dma, dma_addr_t iova)
325 struct vfio_pfn *vpfn;
326 struct rb_node *node = dma->pfn_list.rb_node;
329 vpfn = rb_entry(node, struct vfio_pfn, node);
331 if (iova < vpfn->iova)
332 node = node->rb_left;
333 else if (iova > vpfn->iova)
334 node = node->rb_right;
341 static void vfio_link_pfn(struct vfio_dma *dma,
342 struct vfio_pfn *new)
344 struct rb_node **link, *parent = NULL;
345 struct vfio_pfn *vpfn;
347 link = &dma->pfn_list.rb_node;
350 vpfn = rb_entry(parent, struct vfio_pfn, node);
352 if (new->iova < vpfn->iova)
353 link = &(*link)->rb_left;
355 link = &(*link)->rb_right;
358 rb_link_node(&new->node, parent, link);
359 rb_insert_color(&new->node, &dma->pfn_list);
362 static void vfio_unlink_pfn(struct vfio_dma *dma, struct vfio_pfn *old)
364 rb_erase(&old->node, &dma->pfn_list);
367 static int vfio_add_to_pfn_list(struct vfio_dma *dma, dma_addr_t iova,
370 struct vfio_pfn *vpfn;
372 vpfn = kzalloc(sizeof(*vpfn), GFP_KERNEL);
379 vfio_link_pfn(dma, vpfn);
383 static void vfio_remove_from_pfn_list(struct vfio_dma *dma,
384 struct vfio_pfn *vpfn)
386 vfio_unlink_pfn(dma, vpfn);
390 static struct vfio_pfn *vfio_iova_get_vfio_pfn(struct vfio_dma *dma,
393 struct vfio_pfn *vpfn = vfio_find_vpfn(dma, iova);
400 static int vfio_iova_put_vfio_pfn(struct vfio_dma *dma, struct vfio_pfn *vpfn)
405 if (!vpfn->ref_count) {
406 ret = put_pfn(vpfn->pfn, dma->prot);
407 vfio_remove_from_pfn_list(dma, vpfn);
412 static int mm_lock_acct(struct task_struct *task, struct mm_struct *mm,
413 bool lock_cap, long npage)
415 int ret = mmap_write_lock_killable(mm);
420 ret = __account_locked_vm(mm, abs(npage), npage > 0, task, lock_cap);
421 mmap_write_unlock(mm);
425 static int vfio_lock_acct(struct vfio_dma *dma, long npage, bool async)
427 struct mm_struct *mm;
434 if (async && !mmget_not_zero(mm))
435 return -ESRCH; /* process exited */
437 ret = mm_lock_acct(dma->task, mm, dma->lock_cap, npage);
439 dma->locked_vm += npage;
448 * Some mappings aren't backed by a struct page, for example an mmap'd
449 * MMIO range for our own or another device. These use a different
450 * pfn conversion and shouldn't be tracked as locked pages.
451 * For compound pages, any driver that sets the reserved bit in head
452 * page needs to set the reserved bit in all subpages to be safe.
454 static bool is_invalid_reserved_pfn(unsigned long pfn)
457 return PageReserved(pfn_to_page(pfn));
462 static int put_pfn(unsigned long pfn, int prot)
464 if (!is_invalid_reserved_pfn(pfn)) {
465 struct page *page = pfn_to_page(pfn);
467 unpin_user_pages_dirty_lock(&page, 1, prot & IOMMU_WRITE);
473 #define VFIO_BATCH_MAX_CAPACITY (PAGE_SIZE / sizeof(struct page *))
475 static void vfio_batch_init(struct vfio_batch *batch)
480 if (unlikely(disable_hugepages))
483 batch->pages = (struct page **) __get_free_page(GFP_KERNEL);
487 batch->capacity = VFIO_BATCH_MAX_CAPACITY;
491 batch->pages = &batch->fallback_page;
495 static void vfio_batch_unpin(struct vfio_batch *batch, struct vfio_dma *dma)
497 while (batch->size) {
498 unsigned long pfn = page_to_pfn(batch->pages[batch->offset]);
500 put_pfn(pfn, dma->prot);
506 static void vfio_batch_fini(struct vfio_batch *batch)
508 if (batch->capacity == VFIO_BATCH_MAX_CAPACITY)
509 free_page((unsigned long)batch->pages);
512 static int follow_fault_pfn(struct vm_area_struct *vma, struct mm_struct *mm,
513 unsigned long vaddr, unsigned long *pfn,
520 ret = follow_pte(vma->vm_mm, vaddr, &ptep, &ptl);
522 bool unlocked = false;
524 ret = fixup_user_fault(mm, vaddr,
526 (write_fault ? FAULT_FLAG_WRITE : 0),
534 ret = follow_pte(vma->vm_mm, vaddr, &ptep, &ptl);
539 if (write_fault && !pte_write(*ptep))
542 *pfn = pte_pfn(*ptep);
544 pte_unmap_unlock(ptep, ptl);
549 * Returns the positive number of pfns successfully obtained or a negative
552 static int vaddr_get_pfns(struct mm_struct *mm, unsigned long vaddr,
553 long npages, int prot, unsigned long *pfn,
556 struct vm_area_struct *vma;
557 unsigned int flags = 0;
560 if (prot & IOMMU_WRITE)
564 ret = pin_user_pages_remote(mm, vaddr, npages, flags | FOLL_LONGTERM,
570 * The zero page is always resident, we don't need to pin it
571 * and it falls into our invalid/reserved test so we don't
572 * unpin in put_pfn(). Unpin all zero pages in the batch here.
574 for (i = 0 ; i < ret; i++) {
575 if (unlikely(is_zero_pfn(page_to_pfn(pages[i]))))
576 unpin_user_page(pages[i]);
579 *pfn = page_to_pfn(pages[0]);
583 vaddr = untagged_addr_remote(mm, vaddr);
586 vma = vma_lookup(mm, vaddr);
588 if (vma && vma->vm_flags & VM_PFNMAP) {
589 ret = follow_fault_pfn(vma, mm, vaddr, pfn, prot & IOMMU_WRITE);
594 if (is_invalid_reserved_pfn(*pfn))
601 mmap_read_unlock(mm);
606 * Attempt to pin pages. We really don't want to track all the pfns and
607 * the iommu can only map chunks of consecutive pfns anyway, so get the
608 * first page and all consecutive pages with the same locking.
610 static long vfio_pin_pages_remote(struct vfio_dma *dma, unsigned long vaddr,
611 long npage, unsigned long *pfn_base,
612 unsigned long limit, struct vfio_batch *batch)
615 struct mm_struct *mm = current->mm;
616 long ret, pinned = 0, lock_acct = 0;
618 dma_addr_t iova = vaddr - dma->vaddr + dma->iova;
620 /* This code path is only user initiated */
625 /* Leftover pages in batch from an earlier call. */
626 *pfn_base = page_to_pfn(batch->pages[batch->offset]);
628 rsvd = is_invalid_reserved_pfn(*pfn_base);
635 /* Empty batch, so refill it. */
636 long req_pages = min_t(long, npage, batch->capacity);
638 ret = vaddr_get_pfns(mm, vaddr, req_pages, dma->prot,
648 rsvd = is_invalid_reserved_pfn(*pfn_base);
653 * pfn is preset for the first iteration of this inner loop and
654 * updated at the end to handle a VM_PFNMAP pfn. In that case,
655 * batch->pages isn't valid (there's no struct page), so allow
656 * batch->pages to be touched only when there's more than one
657 * pfn to check, which guarantees the pfns are from a
661 if (pfn != *pfn_base + pinned ||
662 rsvd != is_invalid_reserved_pfn(pfn))
666 * Reserved pages aren't counted against the user,
667 * externally pinned pages are already counted against
670 if (!rsvd && !vfio_find_vpfn(dma, iova)) {
671 if (!dma->lock_cap &&
672 mm->locked_vm + lock_acct + 1 > limit) {
673 pr_warn("%s: RLIMIT_MEMLOCK (%ld) exceeded\n",
674 __func__, limit << PAGE_SHIFT);
691 pfn = page_to_pfn(batch->pages[batch->offset]);
694 if (unlikely(disable_hugepages))
699 ret = vfio_lock_acct(dma, lock_acct, false);
702 if (batch->size == 1 && !batch->offset) {
703 /* May be a VM_PFNMAP pfn, which the batch can't remember. */
704 put_pfn(pfn, dma->prot);
709 if (pinned && !rsvd) {
710 for (pfn = *pfn_base ; pinned ; pfn++, pinned--)
711 put_pfn(pfn, dma->prot);
713 vfio_batch_unpin(batch, dma);
721 static long vfio_unpin_pages_remote(struct vfio_dma *dma, dma_addr_t iova,
722 unsigned long pfn, long npage,
725 long unlocked = 0, locked = 0;
728 for (i = 0; i < npage; i++, iova += PAGE_SIZE) {
729 if (put_pfn(pfn++, dma->prot)) {
731 if (vfio_find_vpfn(dma, iova))
737 vfio_lock_acct(dma, locked - unlocked, true);
742 static int vfio_pin_page_external(struct vfio_dma *dma, unsigned long vaddr,
743 unsigned long *pfn_base, bool do_accounting)
745 struct page *pages[1];
746 struct mm_struct *mm;
750 if (!mmget_not_zero(mm))
753 ret = vaddr_get_pfns(mm, vaddr, 1, dma->prot, pfn_base, pages);
759 if (do_accounting && !is_invalid_reserved_pfn(*pfn_base)) {
760 ret = vfio_lock_acct(dma, 1, false);
762 put_pfn(*pfn_base, dma->prot);
764 pr_warn("%s: Task %s (%d) RLIMIT_MEMLOCK "
765 "(%ld) exceeded\n", __func__,
766 dma->task->comm, task_pid_nr(dma->task),
767 task_rlimit(dma->task, RLIMIT_MEMLOCK));
776 static int vfio_unpin_page_external(struct vfio_dma *dma, dma_addr_t iova,
780 struct vfio_pfn *vpfn = vfio_find_vpfn(dma, iova);
785 unlocked = vfio_iova_put_vfio_pfn(dma, vpfn);
788 vfio_lock_acct(dma, -unlocked, true);
793 static int vfio_iommu_type1_pin_pages(void *iommu_data,
794 struct iommu_group *iommu_group,
795 dma_addr_t user_iova,
799 struct vfio_iommu *iommu = iommu_data;
800 struct vfio_iommu_group *group;
802 unsigned long remote_vaddr;
803 struct vfio_dma *dma;
806 if (!iommu || !pages)
809 /* Supported for v2 version only */
813 mutex_lock(&iommu->lock);
815 if (WARN_ONCE(iommu->vaddr_invalid_count,
816 "vfio_pin_pages not allowed with VFIO_UPDATE_VADDR\n")) {
821 /* Fail if no dma_umap notifier is registered */
822 if (list_empty(&iommu->device_list)) {
828 * If iommu capable domain exist in the container then all pages are
829 * already pinned and accounted. Accounting should be done if there is no
830 * iommu capable domain in the container.
832 do_accounting = list_empty(&iommu->domain_list);
834 for (i = 0; i < npage; i++) {
835 unsigned long phys_pfn;
837 struct vfio_pfn *vpfn;
839 iova = user_iova + PAGE_SIZE * i;
840 dma = vfio_find_dma(iommu, iova, PAGE_SIZE);
846 if ((dma->prot & prot) != prot) {
851 vpfn = vfio_iova_get_vfio_pfn(dma, iova);
853 pages[i] = pfn_to_page(vpfn->pfn);
857 remote_vaddr = dma->vaddr + (iova - dma->iova);
858 ret = vfio_pin_page_external(dma, remote_vaddr, &phys_pfn,
863 ret = vfio_add_to_pfn_list(dma, iova, phys_pfn);
865 if (put_pfn(phys_pfn, dma->prot) && do_accounting)
866 vfio_lock_acct(dma, -1, true);
870 pages[i] = pfn_to_page(phys_pfn);
872 if (iommu->dirty_page_tracking) {
873 unsigned long pgshift = __ffs(iommu->pgsize_bitmap);
876 * Bitmap populated with the smallest supported page
879 bitmap_set(dma->bitmap,
880 (iova - dma->iova) >> pgshift, 1);
885 group = vfio_iommu_find_iommu_group(iommu, iommu_group);
886 if (!group->pinned_page_dirty_scope) {
887 group->pinned_page_dirty_scope = true;
888 iommu->num_non_pinned_groups--;
895 for (j = 0; j < i; j++) {
898 iova = user_iova + PAGE_SIZE * j;
899 dma = vfio_find_dma(iommu, iova, PAGE_SIZE);
900 vfio_unpin_page_external(dma, iova, do_accounting);
904 mutex_unlock(&iommu->lock);
908 static void vfio_iommu_type1_unpin_pages(void *iommu_data,
909 dma_addr_t user_iova, int npage)
911 struct vfio_iommu *iommu = iommu_data;
915 /* Supported for v2 version only */
916 if (WARN_ON(!iommu->v2))
919 mutex_lock(&iommu->lock);
921 do_accounting = list_empty(&iommu->domain_list);
922 for (i = 0; i < npage; i++) {
923 dma_addr_t iova = user_iova + PAGE_SIZE * i;
924 struct vfio_dma *dma;
926 dma = vfio_find_dma(iommu, iova, PAGE_SIZE);
930 vfio_unpin_page_external(dma, iova, do_accounting);
933 mutex_unlock(&iommu->lock);
938 static long vfio_sync_unpin(struct vfio_dma *dma, struct vfio_domain *domain,
939 struct list_head *regions,
940 struct iommu_iotlb_gather *iotlb_gather)
943 struct vfio_regions *entry, *next;
945 iommu_iotlb_sync(domain->domain, iotlb_gather);
947 list_for_each_entry_safe(entry, next, regions, list) {
948 unlocked += vfio_unpin_pages_remote(dma,
950 entry->phys >> PAGE_SHIFT,
951 entry->len >> PAGE_SHIFT,
953 list_del(&entry->list);
963 * Generally, VFIO needs to unpin remote pages after each IOTLB flush.
964 * Therefore, when using IOTLB flush sync interface, VFIO need to keep track
965 * of these regions (currently using a list).
967 * This value specifies maximum number of regions for each IOTLB flush sync.
969 #define VFIO_IOMMU_TLB_SYNC_MAX 512
971 static size_t unmap_unpin_fast(struct vfio_domain *domain,
972 struct vfio_dma *dma, dma_addr_t *iova,
973 size_t len, phys_addr_t phys, long *unlocked,
974 struct list_head *unmapped_list,
976 struct iommu_iotlb_gather *iotlb_gather)
979 struct vfio_regions *entry = kzalloc(sizeof(*entry), GFP_KERNEL);
982 unmapped = iommu_unmap_fast(domain->domain, *iova, len,
990 entry->len = unmapped;
991 list_add_tail(&entry->list, unmapped_list);
999 * Sync if the number of fast-unmap regions hits the limit
1000 * or in case of errors.
1002 if (*unmapped_cnt >= VFIO_IOMMU_TLB_SYNC_MAX || !unmapped) {
1003 *unlocked += vfio_sync_unpin(dma, domain, unmapped_list,
1011 static size_t unmap_unpin_slow(struct vfio_domain *domain,
1012 struct vfio_dma *dma, dma_addr_t *iova,
1013 size_t len, phys_addr_t phys,
1016 size_t unmapped = iommu_unmap(domain->domain, *iova, len);
1019 *unlocked += vfio_unpin_pages_remote(dma, *iova,
1021 unmapped >> PAGE_SHIFT,
1029 static long vfio_unmap_unpin(struct vfio_iommu *iommu, struct vfio_dma *dma,
1032 dma_addr_t iova = dma->iova, end = dma->iova + dma->size;
1033 struct vfio_domain *domain, *d;
1034 LIST_HEAD(unmapped_region_list);
1035 struct iommu_iotlb_gather iotlb_gather;
1036 int unmapped_region_cnt = 0;
1042 if (list_empty(&iommu->domain_list))
1046 * We use the IOMMU to track the physical addresses, otherwise we'd
1047 * need a much more complicated tracking system. Unfortunately that
1048 * means we need to use one of the iommu domains to figure out the
1049 * pfns to unpin. The rest need to be unmapped in advance so we have
1050 * no iommu translations remaining when the pages are unpinned.
1052 domain = d = list_first_entry(&iommu->domain_list,
1053 struct vfio_domain, next);
1055 list_for_each_entry_continue(d, &iommu->domain_list, next) {
1056 iommu_unmap(d->domain, dma->iova, dma->size);
1060 iommu_iotlb_gather_init(&iotlb_gather);
1061 while (iova < end) {
1062 size_t unmapped, len;
1063 phys_addr_t phys, next;
1065 phys = iommu_iova_to_phys(domain->domain, iova);
1066 if (WARN_ON(!phys)) {
1072 * To optimize for fewer iommu_unmap() calls, each of which
1073 * may require hardware cache flushing, try to find the
1074 * largest contiguous physical memory chunk to unmap.
1076 for (len = PAGE_SIZE;
1077 !domain->fgsp && iova + len < end; len += PAGE_SIZE) {
1078 next = iommu_iova_to_phys(domain->domain, iova + len);
1079 if (next != phys + len)
1084 * First, try to use fast unmap/unpin. In case of failure,
1085 * switch to slow unmap/unpin path.
1087 unmapped = unmap_unpin_fast(domain, dma, &iova, len, phys,
1088 &unlocked, &unmapped_region_list,
1089 &unmapped_region_cnt,
1092 unmapped = unmap_unpin_slow(domain, dma, &iova, len,
1094 if (WARN_ON(!unmapped))
1099 dma->iommu_mapped = false;
1101 if (unmapped_region_cnt) {
1102 unlocked += vfio_sync_unpin(dma, domain, &unmapped_region_list,
1106 if (do_accounting) {
1107 vfio_lock_acct(dma, -unlocked, true);
1113 static void vfio_remove_dma(struct vfio_iommu *iommu, struct vfio_dma *dma)
1115 WARN_ON(!RB_EMPTY_ROOT(&dma->pfn_list));
1116 vfio_unmap_unpin(iommu, dma, true);
1117 vfio_unlink_dma(iommu, dma);
1118 put_task_struct(dma->task);
1120 vfio_dma_bitmap_free(dma);
1121 if (dma->vaddr_invalid)
1122 iommu->vaddr_invalid_count--;
1127 static void vfio_update_pgsize_bitmap(struct vfio_iommu *iommu)
1129 struct vfio_domain *domain;
1131 iommu->pgsize_bitmap = ULONG_MAX;
1133 list_for_each_entry(domain, &iommu->domain_list, next)
1134 iommu->pgsize_bitmap &= domain->domain->pgsize_bitmap;
1137 * In case the IOMMU supports page sizes smaller than PAGE_SIZE
1138 * we pretend PAGE_SIZE is supported and hide sub-PAGE_SIZE sizes.
1139 * That way the user will be able to map/unmap buffers whose size/
1140 * start address is aligned with PAGE_SIZE. Pinning code uses that
1141 * granularity while iommu driver can use the sub-PAGE_SIZE size
1142 * to map the buffer.
1144 if (iommu->pgsize_bitmap & ~PAGE_MASK) {
1145 iommu->pgsize_bitmap &= PAGE_MASK;
1146 iommu->pgsize_bitmap |= PAGE_SIZE;
1150 static int update_user_bitmap(u64 __user *bitmap, struct vfio_iommu *iommu,
1151 struct vfio_dma *dma, dma_addr_t base_iova,
1154 unsigned long pgshift = __ffs(pgsize);
1155 unsigned long nbits = dma->size >> pgshift;
1156 unsigned long bit_offset = (dma->iova - base_iova) >> pgshift;
1157 unsigned long copy_offset = bit_offset / BITS_PER_LONG;
1158 unsigned long shift = bit_offset % BITS_PER_LONG;
1159 unsigned long leftover;
1162 * mark all pages dirty if any IOMMU capable device is not able
1163 * to report dirty pages and all pages are pinned and mapped.
1165 if (iommu->num_non_pinned_groups && dma->iommu_mapped)
1166 bitmap_set(dma->bitmap, 0, nbits);
1169 bitmap_shift_left(dma->bitmap, dma->bitmap, shift,
1172 if (copy_from_user(&leftover,
1173 (void __user *)(bitmap + copy_offset),
1177 bitmap_or(dma->bitmap, dma->bitmap, &leftover, shift);
1180 if (copy_to_user((void __user *)(bitmap + copy_offset), dma->bitmap,
1181 DIRTY_BITMAP_BYTES(nbits + shift)))
1187 static int vfio_iova_dirty_bitmap(u64 __user *bitmap, struct vfio_iommu *iommu,
1188 dma_addr_t iova, size_t size, size_t pgsize)
1190 struct vfio_dma *dma;
1192 unsigned long pgshift = __ffs(pgsize);
1196 * GET_BITMAP request must fully cover vfio_dma mappings. Multiple
1197 * vfio_dma mappings may be clubbed by specifying large ranges, but
1198 * there must not be any previous mappings bisected by the range.
1199 * An error will be returned if these conditions are not met.
1201 dma = vfio_find_dma(iommu, iova, 1);
1202 if (dma && dma->iova != iova)
1205 dma = vfio_find_dma(iommu, iova + size - 1, 0);
1206 if (dma && dma->iova + dma->size != iova + size)
1209 for (n = rb_first(&iommu->dma_list); n; n = rb_next(n)) {
1210 struct vfio_dma *dma = rb_entry(n, struct vfio_dma, node);
1212 if (dma->iova < iova)
1215 if (dma->iova > iova + size - 1)
1218 ret = update_user_bitmap(bitmap, iommu, dma, iova, pgsize);
1223 * Re-populate bitmap to include all pinned pages which are
1224 * considered as dirty but exclude pages which are unpinned and
1225 * pages which are marked dirty by vfio_dma_rw()
1227 bitmap_clear(dma->bitmap, 0, dma->size >> pgshift);
1228 vfio_dma_populate_bitmap(dma, pgsize);
1233 static int verify_bitmap_size(uint64_t npages, uint64_t bitmap_size)
1235 if (!npages || !bitmap_size || (bitmap_size > DIRTY_BITMAP_SIZE_MAX) ||
1236 (bitmap_size < DIRTY_BITMAP_BYTES(npages)))
1243 * Notify VFIO drivers using vfio_register_emulated_iommu_dev() to invalidate
1244 * and unmap iovas within the range we're about to unmap. Drivers MUST unpin
1245 * pages in response to an invalidation.
1247 static void vfio_notify_dma_unmap(struct vfio_iommu *iommu,
1248 struct vfio_dma *dma)
1250 struct vfio_device *device;
1252 if (list_empty(&iommu->device_list))
1256 * The device is expected to call vfio_unpin_pages() for any IOVA it has
1257 * pinned within the range. Since vfio_unpin_pages() will eventually
1258 * call back down to this code and try to obtain the iommu->lock we must
1261 mutex_lock(&iommu->device_list_lock);
1262 mutex_unlock(&iommu->lock);
1264 list_for_each_entry(device, &iommu->device_list, iommu_entry)
1265 device->ops->dma_unmap(device, dma->iova, dma->size);
1267 mutex_unlock(&iommu->device_list_lock);
1268 mutex_lock(&iommu->lock);
1271 static int vfio_dma_do_unmap(struct vfio_iommu *iommu,
1272 struct vfio_iommu_type1_dma_unmap *unmap,
1273 struct vfio_bitmap *bitmap)
1275 struct vfio_dma *dma, *dma_last = NULL;
1276 size_t unmapped = 0, pgsize;
1277 int ret = -EINVAL, retries = 0;
1278 unsigned long pgshift;
1279 dma_addr_t iova = unmap->iova;
1280 u64 size = unmap->size;
1281 bool unmap_all = unmap->flags & VFIO_DMA_UNMAP_FLAG_ALL;
1282 bool invalidate_vaddr = unmap->flags & VFIO_DMA_UNMAP_FLAG_VADDR;
1283 struct rb_node *n, *first_n;
1285 mutex_lock(&iommu->lock);
1287 /* Cannot update vaddr if mdev is present. */
1288 if (invalidate_vaddr && !list_empty(&iommu->emulated_iommu_groups)) {
1293 pgshift = __ffs(iommu->pgsize_bitmap);
1294 pgsize = (size_t)1 << pgshift;
1296 if (iova & (pgsize - 1))
1303 } else if (!size || size & (pgsize - 1) ||
1304 iova + size - 1 < iova || size > SIZE_MAX) {
1308 /* When dirty tracking is enabled, allow only min supported pgsize */
1309 if ((unmap->flags & VFIO_DMA_UNMAP_FLAG_GET_DIRTY_BITMAP) &&
1310 (!iommu->dirty_page_tracking || (bitmap->pgsize != pgsize))) {
1314 WARN_ON((pgsize - 1) & PAGE_MASK);
1317 * vfio-iommu-type1 (v1) - User mappings were coalesced together to
1318 * avoid tracking individual mappings. This means that the granularity
1319 * of the original mapping was lost and the user was allowed to attempt
1320 * to unmap any range. Depending on the contiguousness of physical
1321 * memory and page sizes supported by the IOMMU, arbitrary unmaps may
1322 * or may not have worked. We only guaranteed unmap granularity
1323 * matching the original mapping; even though it was untracked here,
1324 * the original mappings are reflected in IOMMU mappings. This
1325 * resulted in a couple unusual behaviors. First, if a range is not
1326 * able to be unmapped, ex. a set of 4k pages that was mapped as a
1327 * 2M hugepage into the IOMMU, the unmap ioctl returns success but with
1328 * a zero sized unmap. Also, if an unmap request overlaps the first
1329 * address of a hugepage, the IOMMU will unmap the entire hugepage.
1330 * This also returns success and the returned unmap size reflects the
1331 * actual size unmapped.
1333 * We attempt to maintain compatibility with this "v1" interface, but
1334 * we take control out of the hands of the IOMMU. Therefore, an unmap
1335 * request offset from the beginning of the original mapping will
1336 * return success with zero sized unmap. And an unmap request covering
1337 * the first iova of mapping will unmap the entire range.
1339 * The v2 version of this interface intends to be more deterministic.
1340 * Unmap requests must fully cover previous mappings. Multiple
1341 * mappings may still be unmaped by specifying large ranges, but there
1342 * must not be any previous mappings bisected by the range. An error
1343 * will be returned if these conditions are not met. The v2 interface
1344 * will only return success and a size of zero if there were no
1345 * mappings within the range.
1347 if (iommu->v2 && !unmap_all) {
1348 dma = vfio_find_dma(iommu, iova, 1);
1349 if (dma && dma->iova != iova)
1352 dma = vfio_find_dma(iommu, iova + size - 1, 0);
1353 if (dma && dma->iova + dma->size != iova + size)
1358 n = first_n = vfio_find_dma_first_node(iommu, iova, size);
1361 dma = rb_entry(n, struct vfio_dma, node);
1362 if (dma->iova >= iova + size)
1365 if (!iommu->v2 && iova > dma->iova)
1368 if (invalidate_vaddr) {
1369 if (dma->vaddr_invalid) {
1370 struct rb_node *last_n = n;
1372 for (n = first_n; n != last_n; n = rb_next(n)) {
1374 struct vfio_dma, node);
1375 dma->vaddr_invalid = false;
1376 iommu->vaddr_invalid_count--;
1382 dma->vaddr_invalid = true;
1383 iommu->vaddr_invalid_count++;
1384 unmapped += dma->size;
1389 if (!RB_EMPTY_ROOT(&dma->pfn_list)) {
1390 if (dma_last == dma) {
1391 BUG_ON(++retries > 10);
1397 vfio_notify_dma_unmap(iommu, dma);
1401 if (unmap->flags & VFIO_DMA_UNMAP_FLAG_GET_DIRTY_BITMAP) {
1402 ret = update_user_bitmap(bitmap->data, iommu, dma,
1408 unmapped += dma->size;
1410 vfio_remove_dma(iommu, dma);
1414 mutex_unlock(&iommu->lock);
1416 /* Report how much was unmapped */
1417 unmap->size = unmapped;
1422 static int vfio_iommu_map(struct vfio_iommu *iommu, dma_addr_t iova,
1423 unsigned long pfn, long npage, int prot)
1425 struct vfio_domain *d;
1428 list_for_each_entry(d, &iommu->domain_list, next) {
1429 ret = iommu_map(d->domain, iova, (phys_addr_t)pfn << PAGE_SHIFT,
1430 npage << PAGE_SHIFT, prot | IOMMU_CACHE,
1441 list_for_each_entry_continue_reverse(d, &iommu->domain_list, next) {
1442 iommu_unmap(d->domain, iova, npage << PAGE_SHIFT);
1449 static int vfio_pin_map_dma(struct vfio_iommu *iommu, struct vfio_dma *dma,
1452 dma_addr_t iova = dma->iova;
1453 unsigned long vaddr = dma->vaddr;
1454 struct vfio_batch batch;
1455 size_t size = map_size;
1457 unsigned long pfn, limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
1460 vfio_batch_init(&batch);
1463 /* Pin a contiguous chunk of memory */
1464 npage = vfio_pin_pages_remote(dma, vaddr + dma->size,
1465 size >> PAGE_SHIFT, &pfn, limit,
1474 ret = vfio_iommu_map(iommu, iova + dma->size, pfn, npage,
1477 vfio_unpin_pages_remote(dma, iova + dma->size, pfn,
1479 vfio_batch_unpin(&batch, dma);
1483 size -= npage << PAGE_SHIFT;
1484 dma->size += npage << PAGE_SHIFT;
1487 vfio_batch_fini(&batch);
1488 dma->iommu_mapped = true;
1491 vfio_remove_dma(iommu, dma);
1497 * Check dma map request is within a valid iova range
1499 static bool vfio_iommu_iova_dma_valid(struct vfio_iommu *iommu,
1500 dma_addr_t start, dma_addr_t end)
1502 struct list_head *iova = &iommu->iova_list;
1503 struct vfio_iova *node;
1505 list_for_each_entry(node, iova, list) {
1506 if (start >= node->start && end <= node->end)
1511 * Check for list_empty() as well since a container with
1512 * a single mdev device will have an empty list.
1514 return list_empty(iova);
1517 static int vfio_change_dma_owner(struct vfio_dma *dma)
1519 struct task_struct *task = current->group_leader;
1520 struct mm_struct *mm = current->mm;
1521 long npage = dma->locked_vm;
1528 lock_cap = capable(CAP_IPC_LOCK);
1529 ret = mm_lock_acct(task, mm, lock_cap, npage);
1533 if (mmget_not_zero(dma->mm)) {
1534 mm_lock_acct(dma->task, dma->mm, dma->lock_cap, -npage);
1538 if (dma->task != task) {
1539 put_task_struct(dma->task);
1540 dma->task = get_task_struct(task);
1545 dma->lock_cap = lock_cap;
1549 static int vfio_dma_do_map(struct vfio_iommu *iommu,
1550 struct vfio_iommu_type1_dma_map *map)
1552 bool set_vaddr = map->flags & VFIO_DMA_MAP_FLAG_VADDR;
1553 dma_addr_t iova = map->iova;
1554 unsigned long vaddr = map->vaddr;
1555 size_t size = map->size;
1556 int ret = 0, prot = 0;
1558 struct vfio_dma *dma;
1560 /* Verify that none of our __u64 fields overflow */
1561 if (map->size != size || map->vaddr != vaddr || map->iova != iova)
1564 /* READ/WRITE from device perspective */
1565 if (map->flags & VFIO_DMA_MAP_FLAG_WRITE)
1566 prot |= IOMMU_WRITE;
1567 if (map->flags & VFIO_DMA_MAP_FLAG_READ)
1570 if ((prot && set_vaddr) || (!prot && !set_vaddr))
1573 mutex_lock(&iommu->lock);
1575 pgsize = (size_t)1 << __ffs(iommu->pgsize_bitmap);
1577 WARN_ON((pgsize - 1) & PAGE_MASK);
1579 if (!size || (size | iova | vaddr) & (pgsize - 1)) {
1584 /* Don't allow IOVA or virtual address wrap */
1585 if (iova + size - 1 < iova || vaddr + size - 1 < vaddr) {
1590 dma = vfio_find_dma(iommu, iova, size);
1594 } else if (!dma->vaddr_invalid || dma->iova != iova ||
1595 dma->size != size) {
1598 ret = vfio_change_dma_owner(dma);
1602 dma->vaddr_invalid = false;
1603 iommu->vaddr_invalid_count--;
1611 if (!iommu->dma_avail) {
1616 if (!vfio_iommu_iova_dma_valid(iommu, iova, iova + size - 1)) {
1621 dma = kzalloc(sizeof(*dma), GFP_KERNEL);
1633 * We need to be able to both add to a task's locked memory and test
1634 * against the locked memory limit and we need to be able to do both
1635 * outside of this call path as pinning can be asynchronous via the
1636 * external interfaces for mdev devices. RLIMIT_MEMLOCK requires a
1637 * task_struct. Save the group_leader so that all DMA tracking uses
1638 * the same task, to make debugging easier. VM locked pages requires
1639 * an mm_struct, so grab the mm in case the task dies.
1641 get_task_struct(current->group_leader);
1642 dma->task = current->group_leader;
1643 dma->lock_cap = capable(CAP_IPC_LOCK);
1644 dma->mm = current->mm;
1647 dma->pfn_list = RB_ROOT;
1649 /* Insert zero-sized and grow as we map chunks of it */
1650 vfio_link_dma(iommu, dma);
1652 /* Don't pin and map if container doesn't contain IOMMU capable domain*/
1653 if (list_empty(&iommu->domain_list))
1656 ret = vfio_pin_map_dma(iommu, dma, size);
1658 if (!ret && iommu->dirty_page_tracking) {
1659 ret = vfio_dma_bitmap_alloc(dma, pgsize);
1661 vfio_remove_dma(iommu, dma);
1665 mutex_unlock(&iommu->lock);
1669 static int vfio_iommu_replay(struct vfio_iommu *iommu,
1670 struct vfio_domain *domain)
1672 struct vfio_batch batch;
1673 struct vfio_domain *d = NULL;
1675 unsigned long limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
1678 /* Arbitrarily pick the first domain in the list for lookups */
1679 if (!list_empty(&iommu->domain_list))
1680 d = list_first_entry(&iommu->domain_list,
1681 struct vfio_domain, next);
1683 vfio_batch_init(&batch);
1685 n = rb_first(&iommu->dma_list);
1687 for (; n; n = rb_next(n)) {
1688 struct vfio_dma *dma;
1691 dma = rb_entry(n, struct vfio_dma, node);
1694 while (iova < dma->iova + dma->size) {
1698 if (dma->iommu_mapped) {
1702 if (WARN_ON(!d)) { /* mapped w/o a domain?! */
1707 phys = iommu_iova_to_phys(d->domain, iova);
1709 if (WARN_ON(!phys)) {
1717 while (i < dma->iova + dma->size &&
1718 p == iommu_iova_to_phys(d->domain, i)) {
1725 unsigned long vaddr = dma->vaddr +
1727 size_t n = dma->iova + dma->size - iova;
1730 npage = vfio_pin_pages_remote(dma, vaddr,
1740 phys = pfn << PAGE_SHIFT;
1741 size = npage << PAGE_SHIFT;
1744 ret = iommu_map(domain->domain, iova, phys, size,
1745 dma->prot | IOMMU_CACHE, GFP_KERNEL);
1747 if (!dma->iommu_mapped) {
1748 vfio_unpin_pages_remote(dma, iova,
1752 vfio_batch_unpin(&batch, dma);
1761 /* All dmas are now mapped, defer to second tree walk for unwind */
1762 for (n = rb_first(&iommu->dma_list); n; n = rb_next(n)) {
1763 struct vfio_dma *dma = rb_entry(n, struct vfio_dma, node);
1765 dma->iommu_mapped = true;
1768 vfio_batch_fini(&batch);
1772 for (; n; n = rb_prev(n)) {
1773 struct vfio_dma *dma = rb_entry(n, struct vfio_dma, node);
1776 if (dma->iommu_mapped) {
1777 iommu_unmap(domain->domain, dma->iova, dma->size);
1782 while (iova < dma->iova + dma->size) {
1783 phys_addr_t phys, p;
1787 phys = iommu_iova_to_phys(domain->domain, iova);
1796 while (i < dma->iova + dma->size &&
1797 p == iommu_iova_to_phys(domain->domain, i)) {
1803 iommu_unmap(domain->domain, iova, size);
1804 vfio_unpin_pages_remote(dma, iova, phys >> PAGE_SHIFT,
1805 size >> PAGE_SHIFT, true);
1809 vfio_batch_fini(&batch);
1814 * We change our unmap behavior slightly depending on whether the IOMMU
1815 * supports fine-grained superpages. IOMMUs like AMD-Vi will use a superpage
1816 * for practically any contiguous power-of-two mapping we give it. This means
1817 * we don't need to look for contiguous chunks ourselves to make unmapping
1818 * more efficient. On IOMMUs with coarse-grained super pages, like Intel VT-d
1819 * with discrete 2M/1G/512G/1T superpages, identifying contiguous chunks
1820 * significantly boosts non-hugetlbfs mappings and doesn't seem to hurt when
1821 * hugetlbfs is in use.
1823 static void vfio_test_domain_fgsp(struct vfio_domain *domain, struct list_head *regions)
1825 int ret, order = get_order(PAGE_SIZE * 2);
1826 struct vfio_iova *region;
1830 pages = alloc_pages(GFP_KERNEL | __GFP_ZERO, order);
1834 list_for_each_entry(region, regions, list) {
1835 start = ALIGN(region->start, PAGE_SIZE * 2);
1836 if (start >= region->end || (region->end - start < PAGE_SIZE * 2))
1839 ret = iommu_map(domain->domain, start, page_to_phys(pages), PAGE_SIZE * 2,
1840 IOMMU_READ | IOMMU_WRITE | IOMMU_CACHE, GFP_KERNEL);
1842 size_t unmapped = iommu_unmap(domain->domain, start, PAGE_SIZE);
1844 if (unmapped == PAGE_SIZE)
1845 iommu_unmap(domain->domain, start + PAGE_SIZE, PAGE_SIZE);
1847 domain->fgsp = true;
1852 __free_pages(pages, order);
1855 static struct vfio_iommu_group *find_iommu_group(struct vfio_domain *domain,
1856 struct iommu_group *iommu_group)
1858 struct vfio_iommu_group *g;
1860 list_for_each_entry(g, &domain->group_list, next) {
1861 if (g->iommu_group == iommu_group)
1868 static struct vfio_iommu_group*
1869 vfio_iommu_find_iommu_group(struct vfio_iommu *iommu,
1870 struct iommu_group *iommu_group)
1872 struct vfio_iommu_group *group;
1873 struct vfio_domain *domain;
1875 list_for_each_entry(domain, &iommu->domain_list, next) {
1876 group = find_iommu_group(domain, iommu_group);
1881 list_for_each_entry(group, &iommu->emulated_iommu_groups, next)
1882 if (group->iommu_group == iommu_group)
1887 static bool vfio_iommu_has_sw_msi(struct list_head *group_resv_regions,
1890 struct iommu_resv_region *region;
1893 list_for_each_entry(region, group_resv_regions, list) {
1895 * The presence of any 'real' MSI regions should take
1896 * precedence over the software-managed one if the
1897 * IOMMU driver happens to advertise both types.
1899 if (region->type == IOMMU_RESV_MSI) {
1904 if (region->type == IOMMU_RESV_SW_MSI) {
1905 *base = region->start;
1914 * This is a helper function to insert an address range to iova list.
1915 * The list is initially created with a single entry corresponding to
1916 * the IOMMU domain geometry to which the device group is attached.
1917 * The list aperture gets modified when a new domain is added to the
1918 * container if the new aperture doesn't conflict with the current one
1919 * or with any existing dma mappings. The list is also modified to
1920 * exclude any reserved regions associated with the device group.
1922 static int vfio_iommu_iova_insert(struct list_head *head,
1923 dma_addr_t start, dma_addr_t end)
1925 struct vfio_iova *region;
1927 region = kmalloc(sizeof(*region), GFP_KERNEL);
1931 INIT_LIST_HEAD(®ion->list);
1932 region->start = start;
1935 list_add_tail(®ion->list, head);
1940 * Check the new iommu aperture conflicts with existing aper or with any
1941 * existing dma mappings.
1943 static bool vfio_iommu_aper_conflict(struct vfio_iommu *iommu,
1944 dma_addr_t start, dma_addr_t end)
1946 struct vfio_iova *first, *last;
1947 struct list_head *iova = &iommu->iova_list;
1949 if (list_empty(iova))
1952 /* Disjoint sets, return conflict */
1953 first = list_first_entry(iova, struct vfio_iova, list);
1954 last = list_last_entry(iova, struct vfio_iova, list);
1955 if (start > last->end || end < first->start)
1958 /* Check for any existing dma mappings below the new start */
1959 if (start > first->start) {
1960 if (vfio_find_dma(iommu, first->start, start - first->start))
1964 /* Check for any existing dma mappings beyond the new end */
1965 if (end < last->end) {
1966 if (vfio_find_dma(iommu, end + 1, last->end - end))
1974 * Resize iommu iova aperture window. This is called only if the new
1975 * aperture has no conflict with existing aperture and dma mappings.
1977 static int vfio_iommu_aper_resize(struct list_head *iova,
1978 dma_addr_t start, dma_addr_t end)
1980 struct vfio_iova *node, *next;
1982 if (list_empty(iova))
1983 return vfio_iommu_iova_insert(iova, start, end);
1985 /* Adjust iova list start */
1986 list_for_each_entry_safe(node, next, iova, list) {
1987 if (start < node->start)
1989 if (start >= node->start && start < node->end) {
1990 node->start = start;
1993 /* Delete nodes before new start */
1994 list_del(&node->list);
1998 /* Adjust iova list end */
1999 list_for_each_entry_safe(node, next, iova, list) {
2000 if (end > node->end)
2002 if (end > node->start && end <= node->end) {
2006 /* Delete nodes after new end */
2007 list_del(&node->list);
2015 * Check reserved region conflicts with existing dma mappings
2017 static bool vfio_iommu_resv_conflict(struct vfio_iommu *iommu,
2018 struct list_head *resv_regions)
2020 struct iommu_resv_region *region;
2022 /* Check for conflict with existing dma mappings */
2023 list_for_each_entry(region, resv_regions, list) {
2024 if (region->type == IOMMU_RESV_DIRECT_RELAXABLE)
2027 if (vfio_find_dma(iommu, region->start, region->length))
2035 * Check iova region overlap with reserved regions and
2036 * exclude them from the iommu iova range
2038 static int vfio_iommu_resv_exclude(struct list_head *iova,
2039 struct list_head *resv_regions)
2041 struct iommu_resv_region *resv;
2042 struct vfio_iova *n, *next;
2044 list_for_each_entry(resv, resv_regions, list) {
2045 phys_addr_t start, end;
2047 if (resv->type == IOMMU_RESV_DIRECT_RELAXABLE)
2050 start = resv->start;
2051 end = resv->start + resv->length - 1;
2053 list_for_each_entry_safe(n, next, iova, list) {
2057 if (start > n->end || end < n->start)
2060 * Insert a new node if current node overlaps with the
2061 * reserve region to exclude that from valid iova range.
2062 * Note that, new node is inserted before the current
2063 * node and finally the current node is deleted keeping
2064 * the list updated and sorted.
2066 if (start > n->start)
2067 ret = vfio_iommu_iova_insert(&n->list, n->start,
2069 if (!ret && end < n->end)
2070 ret = vfio_iommu_iova_insert(&n->list, end + 1,
2080 if (list_empty(iova))
2086 static void vfio_iommu_resv_free(struct list_head *resv_regions)
2088 struct iommu_resv_region *n, *next;
2090 list_for_each_entry_safe(n, next, resv_regions, list) {
2096 static void vfio_iommu_iova_free(struct list_head *iova)
2098 struct vfio_iova *n, *next;
2100 list_for_each_entry_safe(n, next, iova, list) {
2106 static int vfio_iommu_iova_get_copy(struct vfio_iommu *iommu,
2107 struct list_head *iova_copy)
2109 struct list_head *iova = &iommu->iova_list;
2110 struct vfio_iova *n;
2113 list_for_each_entry(n, iova, list) {
2114 ret = vfio_iommu_iova_insert(iova_copy, n->start, n->end);
2122 vfio_iommu_iova_free(iova_copy);
2126 static void vfio_iommu_iova_insert_copy(struct vfio_iommu *iommu,
2127 struct list_head *iova_copy)
2129 struct list_head *iova = &iommu->iova_list;
2131 vfio_iommu_iova_free(iova);
2133 list_splice_tail(iova_copy, iova);
2136 static int vfio_iommu_domain_alloc(struct device *dev, void *data)
2138 struct iommu_domain **domain = data;
2140 *domain = iommu_domain_alloc(dev->bus);
2141 return 1; /* Don't iterate */
2144 static int vfio_iommu_type1_attach_group(void *iommu_data,
2145 struct iommu_group *iommu_group, enum vfio_group_type type)
2147 struct vfio_iommu *iommu = iommu_data;
2148 struct vfio_iommu_group *group;
2149 struct vfio_domain *domain, *d;
2151 phys_addr_t resv_msi_base = 0;
2152 struct iommu_domain_geometry *geo;
2153 LIST_HEAD(iova_copy);
2154 LIST_HEAD(group_resv_regions);
2157 mutex_lock(&iommu->lock);
2159 /* Attach could require pinning, so disallow while vaddr is invalid. */
2160 if (iommu->vaddr_invalid_count)
2163 /* Check for duplicates */
2165 if (vfio_iommu_find_iommu_group(iommu, iommu_group))
2169 group = kzalloc(sizeof(*group), GFP_KERNEL);
2172 group->iommu_group = iommu_group;
2174 if (type == VFIO_EMULATED_IOMMU) {
2175 list_add(&group->next, &iommu->emulated_iommu_groups);
2177 * An emulated IOMMU group cannot dirty memory directly, it can
2178 * only use interfaces that provide dirty tracking.
2179 * The iommu scope can only be promoted with the addition of a
2180 * dirty tracking group.
2182 group->pinned_page_dirty_scope = true;
2188 domain = kzalloc(sizeof(*domain), GFP_KERNEL);
2190 goto out_free_group;
2193 * Going via the iommu_group iterator avoids races, and trivially gives
2194 * us a representative device for the IOMMU API call. We don't actually
2195 * want to iterate beyond the first device (if any).
2198 iommu_group_for_each_dev(iommu_group, &domain->domain,
2199 vfio_iommu_domain_alloc);
2200 if (!domain->domain)
2201 goto out_free_domain;
2203 if (iommu->nesting) {
2204 ret = iommu_enable_nesting(domain->domain);
2209 ret = iommu_attach_group(domain->domain, group->iommu_group);
2213 /* Get aperture info */
2214 geo = &domain->domain->geometry;
2215 if (vfio_iommu_aper_conflict(iommu, geo->aperture_start,
2216 geo->aperture_end)) {
2221 ret = iommu_get_group_resv_regions(iommu_group, &group_resv_regions);
2225 if (vfio_iommu_resv_conflict(iommu, &group_resv_regions)) {
2231 * We don't want to work on the original iova list as the list
2232 * gets modified and in case of failure we have to retain the
2233 * original list. Get a copy here.
2235 ret = vfio_iommu_iova_get_copy(iommu, &iova_copy);
2239 ret = vfio_iommu_aper_resize(&iova_copy, geo->aperture_start,
2244 ret = vfio_iommu_resv_exclude(&iova_copy, &group_resv_regions);
2248 resv_msi = vfio_iommu_has_sw_msi(&group_resv_regions, &resv_msi_base);
2250 INIT_LIST_HEAD(&domain->group_list);
2251 list_add(&group->next, &domain->group_list);
2253 if (!allow_unsafe_interrupts &&
2254 !iommu_group_has_isolated_msi(iommu_group)) {
2255 pr_warn("%s: No interrupt remapping support. Use the module param \"allow_unsafe_interrupts\" to enable VFIO IOMMU support on this platform\n",
2262 * If the IOMMU can block non-coherent operations (ie PCIe TLPs with
2263 * no-snoop set) then VFIO always turns this feature on because on Intel
2264 * platforms it optimizes KVM to disable wbinvd emulation.
2266 if (domain->domain->ops->enforce_cache_coherency)
2267 domain->enforce_cache_coherency =
2268 domain->domain->ops->enforce_cache_coherency(
2272 * Try to match an existing compatible domain. We don't want to
2273 * preclude an IOMMU driver supporting multiple bus_types and being
2274 * able to include different bus_types in the same IOMMU domain, so
2275 * we test whether the domains use the same iommu_ops rather than
2276 * testing if they're on the same bus_type.
2278 list_for_each_entry(d, &iommu->domain_list, next) {
2279 if (d->domain->ops == domain->domain->ops &&
2280 d->enforce_cache_coherency ==
2281 domain->enforce_cache_coherency) {
2282 iommu_detach_group(domain->domain, group->iommu_group);
2283 if (!iommu_attach_group(d->domain,
2284 group->iommu_group)) {
2285 list_add(&group->next, &d->group_list);
2286 iommu_domain_free(domain->domain);
2291 ret = iommu_attach_group(domain->domain,
2292 group->iommu_group);
2298 vfio_test_domain_fgsp(domain, &iova_copy);
2300 /* replay mappings on new domains */
2301 ret = vfio_iommu_replay(iommu, domain);
2306 ret = iommu_get_msi_cookie(domain->domain, resv_msi_base);
2307 if (ret && ret != -ENODEV)
2311 list_add(&domain->next, &iommu->domain_list);
2312 vfio_update_pgsize_bitmap(iommu);
2314 /* Delete the old one and insert new iova list */
2315 vfio_iommu_iova_insert_copy(iommu, &iova_copy);
2318 * An iommu backed group can dirty memory directly and therefore
2319 * demotes the iommu scope until it declares itself dirty tracking
2320 * capable via the page pinning interface.
2322 iommu->num_non_pinned_groups++;
2323 mutex_unlock(&iommu->lock);
2324 vfio_iommu_resv_free(&group_resv_regions);
2329 iommu_detach_group(domain->domain, group->iommu_group);
2331 iommu_domain_free(domain->domain);
2332 vfio_iommu_iova_free(&iova_copy);
2333 vfio_iommu_resv_free(&group_resv_regions);
2339 mutex_unlock(&iommu->lock);
2343 static void vfio_iommu_unmap_unpin_all(struct vfio_iommu *iommu)
2345 struct rb_node *node;
2347 while ((node = rb_first(&iommu->dma_list)))
2348 vfio_remove_dma(iommu, rb_entry(node, struct vfio_dma, node));
2351 static void vfio_iommu_unmap_unpin_reaccount(struct vfio_iommu *iommu)
2353 struct rb_node *n, *p;
2355 n = rb_first(&iommu->dma_list);
2356 for (; n; n = rb_next(n)) {
2357 struct vfio_dma *dma;
2358 long locked = 0, unlocked = 0;
2360 dma = rb_entry(n, struct vfio_dma, node);
2361 unlocked += vfio_unmap_unpin(iommu, dma, false);
2362 p = rb_first(&dma->pfn_list);
2363 for (; p; p = rb_next(p)) {
2364 struct vfio_pfn *vpfn = rb_entry(p, struct vfio_pfn,
2367 if (!is_invalid_reserved_pfn(vpfn->pfn))
2370 vfio_lock_acct(dma, locked - unlocked, true);
2375 * Called when a domain is removed in detach. It is possible that
2376 * the removed domain decided the iova aperture window. Modify the
2377 * iova aperture with the smallest window among existing domains.
2379 static void vfio_iommu_aper_expand(struct vfio_iommu *iommu,
2380 struct list_head *iova_copy)
2382 struct vfio_domain *domain;
2383 struct vfio_iova *node;
2384 dma_addr_t start = 0;
2385 dma_addr_t end = (dma_addr_t)~0;
2387 if (list_empty(iova_copy))
2390 list_for_each_entry(domain, &iommu->domain_list, next) {
2391 struct iommu_domain_geometry *geo = &domain->domain->geometry;
2393 if (geo->aperture_start > start)
2394 start = geo->aperture_start;
2395 if (geo->aperture_end < end)
2396 end = geo->aperture_end;
2399 /* Modify aperture limits. The new aper is either same or bigger */
2400 node = list_first_entry(iova_copy, struct vfio_iova, list);
2401 node->start = start;
2402 node = list_last_entry(iova_copy, struct vfio_iova, list);
2407 * Called when a group is detached. The reserved regions for that
2408 * group can be part of valid iova now. But since reserved regions
2409 * may be duplicated among groups, populate the iova valid regions
2412 static int vfio_iommu_resv_refresh(struct vfio_iommu *iommu,
2413 struct list_head *iova_copy)
2415 struct vfio_domain *d;
2416 struct vfio_iommu_group *g;
2417 struct vfio_iova *node;
2418 dma_addr_t start, end;
2419 LIST_HEAD(resv_regions);
2422 if (list_empty(iova_copy))
2425 list_for_each_entry(d, &iommu->domain_list, next) {
2426 list_for_each_entry(g, &d->group_list, next) {
2427 ret = iommu_get_group_resv_regions(g->iommu_group,
2434 node = list_first_entry(iova_copy, struct vfio_iova, list);
2435 start = node->start;
2436 node = list_last_entry(iova_copy, struct vfio_iova, list);
2439 /* purge the iova list and create new one */
2440 vfio_iommu_iova_free(iova_copy);
2442 ret = vfio_iommu_aper_resize(iova_copy, start, end);
2446 /* Exclude current reserved regions from iova ranges */
2447 ret = vfio_iommu_resv_exclude(iova_copy, &resv_regions);
2449 vfio_iommu_resv_free(&resv_regions);
2453 static void vfio_iommu_type1_detach_group(void *iommu_data,
2454 struct iommu_group *iommu_group)
2456 struct vfio_iommu *iommu = iommu_data;
2457 struct vfio_domain *domain;
2458 struct vfio_iommu_group *group;
2459 bool update_dirty_scope = false;
2460 LIST_HEAD(iova_copy);
2462 mutex_lock(&iommu->lock);
2463 list_for_each_entry(group, &iommu->emulated_iommu_groups, next) {
2464 if (group->iommu_group != iommu_group)
2466 update_dirty_scope = !group->pinned_page_dirty_scope;
2467 list_del(&group->next);
2470 if (list_empty(&iommu->emulated_iommu_groups) &&
2471 list_empty(&iommu->domain_list)) {
2472 WARN_ON(!list_empty(&iommu->device_list));
2473 vfio_iommu_unmap_unpin_all(iommu);
2475 goto detach_group_done;
2479 * Get a copy of iova list. This will be used to update
2480 * and to replace the current one later. Please note that
2481 * we will leave the original list as it is if update fails.
2483 vfio_iommu_iova_get_copy(iommu, &iova_copy);
2485 list_for_each_entry(domain, &iommu->domain_list, next) {
2486 group = find_iommu_group(domain, iommu_group);
2490 iommu_detach_group(domain->domain, group->iommu_group);
2491 update_dirty_scope = !group->pinned_page_dirty_scope;
2492 list_del(&group->next);
2495 * Group ownership provides privilege, if the group list is
2496 * empty, the domain goes away. If it's the last domain with
2497 * iommu and external domain doesn't exist, then all the
2498 * mappings go away too. If it's the last domain with iommu and
2499 * external domain exist, update accounting
2501 if (list_empty(&domain->group_list)) {
2502 if (list_is_singular(&iommu->domain_list)) {
2503 if (list_empty(&iommu->emulated_iommu_groups)) {
2504 WARN_ON(!list_empty(
2505 &iommu->device_list));
2506 vfio_iommu_unmap_unpin_all(iommu);
2508 vfio_iommu_unmap_unpin_reaccount(iommu);
2511 iommu_domain_free(domain->domain);
2512 list_del(&domain->next);
2514 vfio_iommu_aper_expand(iommu, &iova_copy);
2515 vfio_update_pgsize_bitmap(iommu);
2520 if (!vfio_iommu_resv_refresh(iommu, &iova_copy))
2521 vfio_iommu_iova_insert_copy(iommu, &iova_copy);
2523 vfio_iommu_iova_free(&iova_copy);
2527 * Removal of a group without dirty tracking may allow the iommu scope
2530 if (update_dirty_scope) {
2531 iommu->num_non_pinned_groups--;
2532 if (iommu->dirty_page_tracking)
2533 vfio_iommu_populate_bitmap_full(iommu);
2535 mutex_unlock(&iommu->lock);
2538 static void *vfio_iommu_type1_open(unsigned long arg)
2540 struct vfio_iommu *iommu;
2542 iommu = kzalloc(sizeof(*iommu), GFP_KERNEL);
2544 return ERR_PTR(-ENOMEM);
2547 case VFIO_TYPE1_IOMMU:
2549 case VFIO_TYPE1_NESTING_IOMMU:
2550 iommu->nesting = true;
2552 case VFIO_TYPE1v2_IOMMU:
2557 return ERR_PTR(-EINVAL);
2560 INIT_LIST_HEAD(&iommu->domain_list);
2561 INIT_LIST_HEAD(&iommu->iova_list);
2562 iommu->dma_list = RB_ROOT;
2563 iommu->dma_avail = dma_entry_limit;
2564 mutex_init(&iommu->lock);
2565 mutex_init(&iommu->device_list_lock);
2566 INIT_LIST_HEAD(&iommu->device_list);
2567 iommu->pgsize_bitmap = PAGE_MASK;
2568 INIT_LIST_HEAD(&iommu->emulated_iommu_groups);
2573 static void vfio_release_domain(struct vfio_domain *domain)
2575 struct vfio_iommu_group *group, *group_tmp;
2577 list_for_each_entry_safe(group, group_tmp,
2578 &domain->group_list, next) {
2579 iommu_detach_group(domain->domain, group->iommu_group);
2580 list_del(&group->next);
2584 iommu_domain_free(domain->domain);
2587 static void vfio_iommu_type1_release(void *iommu_data)
2589 struct vfio_iommu *iommu = iommu_data;
2590 struct vfio_domain *domain, *domain_tmp;
2591 struct vfio_iommu_group *group, *next_group;
2593 list_for_each_entry_safe(group, next_group,
2594 &iommu->emulated_iommu_groups, next) {
2595 list_del(&group->next);
2599 vfio_iommu_unmap_unpin_all(iommu);
2601 list_for_each_entry_safe(domain, domain_tmp,
2602 &iommu->domain_list, next) {
2603 vfio_release_domain(domain);
2604 list_del(&domain->next);
2608 vfio_iommu_iova_free(&iommu->iova_list);
2613 static int vfio_domains_have_enforce_cache_coherency(struct vfio_iommu *iommu)
2615 struct vfio_domain *domain;
2618 mutex_lock(&iommu->lock);
2619 list_for_each_entry(domain, &iommu->domain_list, next) {
2620 if (!(domain->enforce_cache_coherency)) {
2625 mutex_unlock(&iommu->lock);
2630 static bool vfio_iommu_has_emulated(struct vfio_iommu *iommu)
2634 mutex_lock(&iommu->lock);
2635 ret = !list_empty(&iommu->emulated_iommu_groups);
2636 mutex_unlock(&iommu->lock);
2640 static int vfio_iommu_type1_check_extension(struct vfio_iommu *iommu,
2644 case VFIO_TYPE1_IOMMU:
2645 case VFIO_TYPE1v2_IOMMU:
2646 case VFIO_TYPE1_NESTING_IOMMU:
2647 case VFIO_UNMAP_ALL:
2649 case VFIO_UPDATE_VADDR:
2651 * Disable this feature if mdevs are present. They cannot
2652 * safely pin/unpin/rw while vaddrs are being updated.
2654 return iommu && !vfio_iommu_has_emulated(iommu);
2655 case VFIO_DMA_CC_IOMMU:
2658 return vfio_domains_have_enforce_cache_coherency(iommu);
2664 static int vfio_iommu_iova_add_cap(struct vfio_info_cap *caps,
2665 struct vfio_iommu_type1_info_cap_iova_range *cap_iovas,
2668 struct vfio_info_cap_header *header;
2669 struct vfio_iommu_type1_info_cap_iova_range *iova_cap;
2671 header = vfio_info_cap_add(caps, size,
2672 VFIO_IOMMU_TYPE1_INFO_CAP_IOVA_RANGE, 1);
2674 return PTR_ERR(header);
2676 iova_cap = container_of(header,
2677 struct vfio_iommu_type1_info_cap_iova_range,
2679 iova_cap->nr_iovas = cap_iovas->nr_iovas;
2680 memcpy(iova_cap->iova_ranges, cap_iovas->iova_ranges,
2681 cap_iovas->nr_iovas * sizeof(*cap_iovas->iova_ranges));
2685 static int vfio_iommu_iova_build_caps(struct vfio_iommu *iommu,
2686 struct vfio_info_cap *caps)
2688 struct vfio_iommu_type1_info_cap_iova_range *cap_iovas;
2689 struct vfio_iova *iova;
2691 int iovas = 0, i = 0, ret;
2693 list_for_each_entry(iova, &iommu->iova_list, list)
2698 * Return 0 as a container with a single mdev device
2699 * will have an empty list
2704 size = struct_size(cap_iovas, iova_ranges, iovas);
2706 cap_iovas = kzalloc(size, GFP_KERNEL);
2710 cap_iovas->nr_iovas = iovas;
2712 list_for_each_entry(iova, &iommu->iova_list, list) {
2713 cap_iovas->iova_ranges[i].start = iova->start;
2714 cap_iovas->iova_ranges[i].end = iova->end;
2718 ret = vfio_iommu_iova_add_cap(caps, cap_iovas, size);
2724 static int vfio_iommu_migration_build_caps(struct vfio_iommu *iommu,
2725 struct vfio_info_cap *caps)
2727 struct vfio_iommu_type1_info_cap_migration cap_mig;
2729 cap_mig.header.id = VFIO_IOMMU_TYPE1_INFO_CAP_MIGRATION;
2730 cap_mig.header.version = 1;
2733 /* support minimum pgsize */
2734 cap_mig.pgsize_bitmap = (size_t)1 << __ffs(iommu->pgsize_bitmap);
2735 cap_mig.max_dirty_bitmap_size = DIRTY_BITMAP_SIZE_MAX;
2737 return vfio_info_add_capability(caps, &cap_mig.header, sizeof(cap_mig));
2740 static int vfio_iommu_dma_avail_build_caps(struct vfio_iommu *iommu,
2741 struct vfio_info_cap *caps)
2743 struct vfio_iommu_type1_info_dma_avail cap_dma_avail;
2745 cap_dma_avail.header.id = VFIO_IOMMU_TYPE1_INFO_DMA_AVAIL;
2746 cap_dma_avail.header.version = 1;
2748 cap_dma_avail.avail = iommu->dma_avail;
2750 return vfio_info_add_capability(caps, &cap_dma_avail.header,
2751 sizeof(cap_dma_avail));
2754 static int vfio_iommu_type1_get_info(struct vfio_iommu *iommu,
2757 struct vfio_iommu_type1_info info;
2758 unsigned long minsz;
2759 struct vfio_info_cap caps = { .buf = NULL, .size = 0 };
2760 unsigned long capsz;
2763 minsz = offsetofend(struct vfio_iommu_type1_info, iova_pgsizes);
2765 /* For backward compatibility, cannot require this */
2766 capsz = offsetofend(struct vfio_iommu_type1_info, cap_offset);
2768 if (copy_from_user(&info, (void __user *)arg, minsz))
2771 if (info.argsz < minsz)
2774 if (info.argsz >= capsz) {
2776 info.cap_offset = 0; /* output, no-recopy necessary */
2779 mutex_lock(&iommu->lock);
2780 info.flags = VFIO_IOMMU_INFO_PGSIZES;
2782 info.iova_pgsizes = iommu->pgsize_bitmap;
2784 ret = vfio_iommu_migration_build_caps(iommu, &caps);
2787 ret = vfio_iommu_dma_avail_build_caps(iommu, &caps);
2790 ret = vfio_iommu_iova_build_caps(iommu, &caps);
2792 mutex_unlock(&iommu->lock);
2798 info.flags |= VFIO_IOMMU_INFO_CAPS;
2800 if (info.argsz < sizeof(info) + caps.size) {
2801 info.argsz = sizeof(info) + caps.size;
2803 vfio_info_cap_shift(&caps, sizeof(info));
2804 if (copy_to_user((void __user *)arg +
2805 sizeof(info), caps.buf,
2810 info.cap_offset = sizeof(info);
2816 return copy_to_user((void __user *)arg, &info, minsz) ?
2820 static int vfio_iommu_type1_map_dma(struct vfio_iommu *iommu,
2823 struct vfio_iommu_type1_dma_map map;
2824 unsigned long minsz;
2825 uint32_t mask = VFIO_DMA_MAP_FLAG_READ | VFIO_DMA_MAP_FLAG_WRITE |
2826 VFIO_DMA_MAP_FLAG_VADDR;
2828 minsz = offsetofend(struct vfio_iommu_type1_dma_map, size);
2830 if (copy_from_user(&map, (void __user *)arg, minsz))
2833 if (map.argsz < minsz || map.flags & ~mask)
2836 return vfio_dma_do_map(iommu, &map);
2839 static int vfio_iommu_type1_unmap_dma(struct vfio_iommu *iommu,
2842 struct vfio_iommu_type1_dma_unmap unmap;
2843 struct vfio_bitmap bitmap = { 0 };
2844 uint32_t mask = VFIO_DMA_UNMAP_FLAG_GET_DIRTY_BITMAP |
2845 VFIO_DMA_UNMAP_FLAG_VADDR |
2846 VFIO_DMA_UNMAP_FLAG_ALL;
2847 unsigned long minsz;
2850 minsz = offsetofend(struct vfio_iommu_type1_dma_unmap, size);
2852 if (copy_from_user(&unmap, (void __user *)arg, minsz))
2855 if (unmap.argsz < minsz || unmap.flags & ~mask)
2858 if ((unmap.flags & VFIO_DMA_UNMAP_FLAG_GET_DIRTY_BITMAP) &&
2859 (unmap.flags & (VFIO_DMA_UNMAP_FLAG_ALL |
2860 VFIO_DMA_UNMAP_FLAG_VADDR)))
2863 if (unmap.flags & VFIO_DMA_UNMAP_FLAG_GET_DIRTY_BITMAP) {
2864 unsigned long pgshift;
2866 if (unmap.argsz < (minsz + sizeof(bitmap)))
2869 if (copy_from_user(&bitmap,
2870 (void __user *)(arg + minsz),
2874 if (!access_ok((void __user *)bitmap.data, bitmap.size))
2877 pgshift = __ffs(bitmap.pgsize);
2878 ret = verify_bitmap_size(unmap.size >> pgshift,
2884 ret = vfio_dma_do_unmap(iommu, &unmap, &bitmap);
2888 return copy_to_user((void __user *)arg, &unmap, minsz) ?
2892 static int vfio_iommu_type1_dirty_pages(struct vfio_iommu *iommu,
2895 struct vfio_iommu_type1_dirty_bitmap dirty;
2896 uint32_t mask = VFIO_IOMMU_DIRTY_PAGES_FLAG_START |
2897 VFIO_IOMMU_DIRTY_PAGES_FLAG_STOP |
2898 VFIO_IOMMU_DIRTY_PAGES_FLAG_GET_BITMAP;
2899 unsigned long minsz;
2905 minsz = offsetofend(struct vfio_iommu_type1_dirty_bitmap, flags);
2907 if (copy_from_user(&dirty, (void __user *)arg, minsz))
2910 if (dirty.argsz < minsz || dirty.flags & ~mask)
2913 /* only one flag should be set at a time */
2914 if (__ffs(dirty.flags) != __fls(dirty.flags))
2917 if (dirty.flags & VFIO_IOMMU_DIRTY_PAGES_FLAG_START) {
2920 mutex_lock(&iommu->lock);
2921 pgsize = 1 << __ffs(iommu->pgsize_bitmap);
2922 if (!iommu->dirty_page_tracking) {
2923 ret = vfio_dma_bitmap_alloc_all(iommu, pgsize);
2925 iommu->dirty_page_tracking = true;
2927 mutex_unlock(&iommu->lock);
2929 } else if (dirty.flags & VFIO_IOMMU_DIRTY_PAGES_FLAG_STOP) {
2930 mutex_lock(&iommu->lock);
2931 if (iommu->dirty_page_tracking) {
2932 iommu->dirty_page_tracking = false;
2933 vfio_dma_bitmap_free_all(iommu);
2935 mutex_unlock(&iommu->lock);
2937 } else if (dirty.flags & VFIO_IOMMU_DIRTY_PAGES_FLAG_GET_BITMAP) {
2938 struct vfio_iommu_type1_dirty_bitmap_get range;
2939 unsigned long pgshift;
2940 size_t data_size = dirty.argsz - minsz;
2941 size_t iommu_pgsize;
2943 if (!data_size || data_size < sizeof(range))
2946 if (copy_from_user(&range, (void __user *)(arg + minsz),
2950 if (range.iova + range.size < range.iova)
2952 if (!access_ok((void __user *)range.bitmap.data,
2956 pgshift = __ffs(range.bitmap.pgsize);
2957 ret = verify_bitmap_size(range.size >> pgshift,
2962 mutex_lock(&iommu->lock);
2964 iommu_pgsize = (size_t)1 << __ffs(iommu->pgsize_bitmap);
2966 /* allow only smallest supported pgsize */
2967 if (range.bitmap.pgsize != iommu_pgsize) {
2971 if (range.iova & (iommu_pgsize - 1)) {
2975 if (!range.size || range.size & (iommu_pgsize - 1)) {
2980 if (iommu->dirty_page_tracking)
2981 ret = vfio_iova_dirty_bitmap(range.bitmap.data,
2984 range.bitmap.pgsize);
2988 mutex_unlock(&iommu->lock);
2996 static long vfio_iommu_type1_ioctl(void *iommu_data,
2997 unsigned int cmd, unsigned long arg)
2999 struct vfio_iommu *iommu = iommu_data;
3002 case VFIO_CHECK_EXTENSION:
3003 return vfio_iommu_type1_check_extension(iommu, arg);
3004 case VFIO_IOMMU_GET_INFO:
3005 return vfio_iommu_type1_get_info(iommu, arg);
3006 case VFIO_IOMMU_MAP_DMA:
3007 return vfio_iommu_type1_map_dma(iommu, arg);
3008 case VFIO_IOMMU_UNMAP_DMA:
3009 return vfio_iommu_type1_unmap_dma(iommu, arg);
3010 case VFIO_IOMMU_DIRTY_PAGES:
3011 return vfio_iommu_type1_dirty_pages(iommu, arg);
3017 static void vfio_iommu_type1_register_device(void *iommu_data,
3018 struct vfio_device *vdev)
3020 struct vfio_iommu *iommu = iommu_data;
3022 if (!vdev->ops->dma_unmap)
3026 * list_empty(&iommu->device_list) is tested under the iommu->lock while
3027 * iteration for dma_unmap must be done under the device_list_lock.
3028 * Holding both locks here allows avoiding the device_list_lock in
3029 * several fast paths. See vfio_notify_dma_unmap()
3031 mutex_lock(&iommu->lock);
3032 mutex_lock(&iommu->device_list_lock);
3033 list_add(&vdev->iommu_entry, &iommu->device_list);
3034 mutex_unlock(&iommu->device_list_lock);
3035 mutex_unlock(&iommu->lock);
3038 static void vfio_iommu_type1_unregister_device(void *iommu_data,
3039 struct vfio_device *vdev)
3041 struct vfio_iommu *iommu = iommu_data;
3043 if (!vdev->ops->dma_unmap)
3046 mutex_lock(&iommu->lock);
3047 mutex_lock(&iommu->device_list_lock);
3048 list_del(&vdev->iommu_entry);
3049 mutex_unlock(&iommu->device_list_lock);
3050 mutex_unlock(&iommu->lock);
3053 static int vfio_iommu_type1_dma_rw_chunk(struct vfio_iommu *iommu,
3054 dma_addr_t user_iova, void *data,
3055 size_t count, bool write,
3058 struct mm_struct *mm;
3059 unsigned long vaddr;
3060 struct vfio_dma *dma;
3061 bool kthread = current->mm == NULL;
3066 dma = vfio_find_dma(iommu, user_iova, 1);
3070 if ((write && !(dma->prot & IOMMU_WRITE)) ||
3071 !(dma->prot & IOMMU_READ))
3075 if (!mmget_not_zero(mm))
3080 else if (current->mm != mm)
3083 offset = user_iova - dma->iova;
3085 if (count > dma->size - offset)
3086 count = dma->size - offset;
3088 vaddr = dma->vaddr + offset;
3091 *copied = copy_to_user((void __user *)vaddr, data,
3093 if (*copied && iommu->dirty_page_tracking) {
3094 unsigned long pgshift = __ffs(iommu->pgsize_bitmap);
3096 * Bitmap populated with the smallest supported page
3099 bitmap_set(dma->bitmap, offset >> pgshift,
3100 ((offset + *copied - 1) >> pgshift) -
3101 (offset >> pgshift) + 1);
3104 *copied = copy_from_user(data, (void __user *)vaddr,
3107 kthread_unuse_mm(mm);
3110 return *copied ? 0 : -EFAULT;
3113 static int vfio_iommu_type1_dma_rw(void *iommu_data, dma_addr_t user_iova,
3114 void *data, size_t count, bool write)
3116 struct vfio_iommu *iommu = iommu_data;
3120 mutex_lock(&iommu->lock);
3122 if (WARN_ONCE(iommu->vaddr_invalid_count,
3123 "vfio_dma_rw not allowed with VFIO_UPDATE_VADDR\n")) {
3129 ret = vfio_iommu_type1_dma_rw_chunk(iommu, user_iova, data,
3130 count, write, &done);
3140 mutex_unlock(&iommu->lock);
3144 static struct iommu_domain *
3145 vfio_iommu_type1_group_iommu_domain(void *iommu_data,
3146 struct iommu_group *iommu_group)
3148 struct iommu_domain *domain = ERR_PTR(-ENODEV);
3149 struct vfio_iommu *iommu = iommu_data;
3150 struct vfio_domain *d;
3152 if (!iommu || !iommu_group)
3153 return ERR_PTR(-EINVAL);
3155 mutex_lock(&iommu->lock);
3156 list_for_each_entry(d, &iommu->domain_list, next) {
3157 if (find_iommu_group(d, iommu_group)) {
3162 mutex_unlock(&iommu->lock);
3167 static const struct vfio_iommu_driver_ops vfio_iommu_driver_ops_type1 = {
3168 .name = "vfio-iommu-type1",
3169 .owner = THIS_MODULE,
3170 .open = vfio_iommu_type1_open,
3171 .release = vfio_iommu_type1_release,
3172 .ioctl = vfio_iommu_type1_ioctl,
3173 .attach_group = vfio_iommu_type1_attach_group,
3174 .detach_group = vfio_iommu_type1_detach_group,
3175 .pin_pages = vfio_iommu_type1_pin_pages,
3176 .unpin_pages = vfio_iommu_type1_unpin_pages,
3177 .register_device = vfio_iommu_type1_register_device,
3178 .unregister_device = vfio_iommu_type1_unregister_device,
3179 .dma_rw = vfio_iommu_type1_dma_rw,
3180 .group_iommu_domain = vfio_iommu_type1_group_iommu_domain,
3183 static int __init vfio_iommu_type1_init(void)
3185 return vfio_register_iommu_driver(&vfio_iommu_driver_ops_type1);
3188 static void __exit vfio_iommu_type1_cleanup(void)
3190 vfio_unregister_iommu_driver(&vfio_iommu_driver_ops_type1);
3193 module_init(vfio_iommu_type1_init);
3194 module_exit(vfio_iommu_type1_cleanup);
3196 MODULE_VERSION(DRIVER_VERSION);
3197 MODULE_LICENSE("GPL v2");
3198 MODULE_AUTHOR(DRIVER_AUTHOR);
3199 MODULE_DESCRIPTION(DRIVER_DESC);