| /* |
| * VFIO: IOMMU DMA mapping support for Type1 IOMMU |
| * |
| * Copyright (C) 2012 Red Hat, Inc. All rights reserved. |
| * Author: Alex Williamson <alex.williamson@redhat.com> |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License version 2 as |
| * published by the Free Software Foundation. |
| * |
| * Derived from original vfio: |
| * Copyright 2010 Cisco Systems, Inc. All rights reserved. |
| * Author: Tom Lyon, pugs@cisco.com |
| * |
| * We arbitrarily define a Type1 IOMMU as one matching the below code. |
| * It could be called the x86 IOMMU as it's designed for AMD-Vi & Intel |
| * VT-d, but that makes it harder to re-use as theoretically anyone |
| * implementing a similar IOMMU could make use of this. We expect the |
| * IOMMU to support the IOMMU API and have few to no restrictions around |
| * the IOVA range that can be mapped. The Type1 IOMMU is currently |
| * optimized for relatively static mappings of a userspace process with |
| * userpsace pages pinned into memory. We also assume devices and IOMMU |
| * domains are PCI based as the IOMMU API is still centered around a |
| * device/bus interface rather than a group interface. |
| */ |
| |
| #include <linux/compat.h> |
| #include <linux/device.h> |
| #include <linux/fs.h> |
| #include <linux/iommu.h> |
| #include <linux/module.h> |
| #include <linux/mm.h> |
| #include <linux/rbtree.h> |
| #include <linux/sched/signal.h> |
| #include <linux/sched/mm.h> |
| #include <linux/slab.h> |
| #include <linux/uaccess.h> |
| #include <linux/vfio.h> |
| #include <linux/workqueue.h> |
| #include <linux/mdev.h> |
| #include <linux/notifier.h> |
| #include <linux/dma-iommu.h> |
| #include <linux/irqdomain.h> |
| |
| #define DRIVER_VERSION "0.2" |
| #define DRIVER_AUTHOR "Alex Williamson <alex.williamson@redhat.com>" |
| #define DRIVER_DESC "Type1 IOMMU driver for VFIO" |
| |
| static bool allow_unsafe_interrupts; |
| module_param_named(allow_unsafe_interrupts, |
| allow_unsafe_interrupts, bool, S_IRUGO | S_IWUSR); |
| MODULE_PARM_DESC(allow_unsafe_interrupts, |
| "Enable VFIO IOMMU support for on platforms without interrupt remapping support."); |
| |
| static bool disable_hugepages; |
| module_param_named(disable_hugepages, |
| disable_hugepages, bool, S_IRUGO | S_IWUSR); |
| MODULE_PARM_DESC(disable_hugepages, |
| "Disable VFIO IOMMU support for IOMMU hugepages."); |
| |
| struct vfio_iommu { |
| struct list_head domain_list; |
| struct vfio_domain *external_domain; /* domain for external user */ |
| struct mutex lock; |
| struct rb_root dma_list; |
| struct blocking_notifier_head notifier; |
| bool v2; |
| bool nesting; |
| }; |
| |
| struct vfio_domain { |
| struct iommu_domain *domain; |
| struct list_head next; |
| struct list_head group_list; |
| int prot; /* IOMMU_CACHE */ |
| bool fgsp; /* Fine-grained super pages */ |
| }; |
| |
| struct vfio_dma { |
| struct rb_node node; |
| dma_addr_t iova; /* Device address */ |
| unsigned long vaddr; /* Process virtual addr */ |
| size_t size; /* Map size (bytes) */ |
| int prot; /* IOMMU_READ/WRITE */ |
| bool iommu_mapped; |
| struct task_struct *task; |
| struct rb_root pfn_list; /* Ex-user pinned pfn list */ |
| }; |
| |
| struct vfio_group { |
| struct iommu_group *iommu_group; |
| struct list_head next; |
| }; |
| |
| /* |
| * Guest RAM pinning working set or DMA target |
| */ |
| struct vfio_pfn { |
| struct rb_node node; |
| dma_addr_t iova; /* Device address */ |
| unsigned long pfn; /* Host pfn */ |
| atomic_t ref_count; |
| }; |
| |
| #define IS_IOMMU_CAP_DOMAIN_IN_CONTAINER(iommu) \ |
| (!list_empty(&iommu->domain_list)) |
| |
| static int put_pfn(unsigned long pfn, int prot); |
| |
| /* |
| * This code handles mapping and unmapping of user data buffers |
| * into DMA'ble space using the IOMMU |
| */ |
| |
| static struct vfio_dma *vfio_find_dma(struct vfio_iommu *iommu, |
| dma_addr_t start, size_t size) |
| { |
| struct rb_node *node = iommu->dma_list.rb_node; |
| |
| while (node) { |
| struct vfio_dma *dma = rb_entry(node, struct vfio_dma, node); |
| |
| if (start + size <= dma->iova) |
| node = node->rb_left; |
| else if (start >= dma->iova + dma->size) |
| node = node->rb_right; |
| else |
| return dma; |
| } |
| |
| return NULL; |
| } |
| |
| static void vfio_link_dma(struct vfio_iommu *iommu, struct vfio_dma *new) |
| { |
| struct rb_node **link = &iommu->dma_list.rb_node, *parent = NULL; |
| struct vfio_dma *dma; |
| |
| while (*link) { |
| parent = *link; |
| dma = rb_entry(parent, struct vfio_dma, node); |
| |
| if (new->iova + new->size <= dma->iova) |
| link = &(*link)->rb_left; |
| else |
| link = &(*link)->rb_right; |
| } |
| |
| rb_link_node(&new->node, parent, link); |
| rb_insert_color(&new->node, &iommu->dma_list); |
| } |
| |
| static void vfio_unlink_dma(struct vfio_iommu *iommu, struct vfio_dma *old) |
| { |
| rb_erase(&old->node, &iommu->dma_list); |
| } |
| |
| /* |
| * Helper Functions for host iova-pfn list |
| */ |
| static struct vfio_pfn *vfio_find_vpfn(struct vfio_dma *dma, dma_addr_t iova) |
| { |
| struct vfio_pfn *vpfn; |
| struct rb_node *node = dma->pfn_list.rb_node; |
| |
| while (node) { |
| vpfn = rb_entry(node, struct vfio_pfn, node); |
| |
| if (iova < vpfn->iova) |
| node = node->rb_left; |
| else if (iova > vpfn->iova) |
| node = node->rb_right; |
| else |
| return vpfn; |
| } |
| return NULL; |
| } |
| |
| static void vfio_link_pfn(struct vfio_dma *dma, |
| struct vfio_pfn *new) |
| { |
| struct rb_node **link, *parent = NULL; |
| struct vfio_pfn *vpfn; |
| |
| link = &dma->pfn_list.rb_node; |
| while (*link) { |
| parent = *link; |
| vpfn = rb_entry(parent, struct vfio_pfn, node); |
| |
| if (new->iova < vpfn->iova) |
| link = &(*link)->rb_left; |
| else |
| link = &(*link)->rb_right; |
| } |
| |
| rb_link_node(&new->node, parent, link); |
| rb_insert_color(&new->node, &dma->pfn_list); |
| } |
| |
| static void vfio_unlink_pfn(struct vfio_dma *dma, struct vfio_pfn *old) |
| { |
| rb_erase(&old->node, &dma->pfn_list); |
| } |
| |
| static int vfio_add_to_pfn_list(struct vfio_dma *dma, dma_addr_t iova, |
| unsigned long pfn) |
| { |
| struct vfio_pfn *vpfn; |
| |
| vpfn = kzalloc(sizeof(*vpfn), GFP_KERNEL); |
| if (!vpfn) |
| return -ENOMEM; |
| |
| vpfn->iova = iova; |
| vpfn->pfn = pfn; |
| atomic_set(&vpfn->ref_count, 1); |
| vfio_link_pfn(dma, vpfn); |
| return 0; |
| } |
| |
| static void vfio_remove_from_pfn_list(struct vfio_dma *dma, |
| struct vfio_pfn *vpfn) |
| { |
| vfio_unlink_pfn(dma, vpfn); |
| kfree(vpfn); |
| } |
| |
| static struct vfio_pfn *vfio_iova_get_vfio_pfn(struct vfio_dma *dma, |
| unsigned long iova) |
| { |
| struct vfio_pfn *vpfn = vfio_find_vpfn(dma, iova); |
| |
| if (vpfn) |
| atomic_inc(&vpfn->ref_count); |
| return vpfn; |
| } |
| |
| static int vfio_iova_put_vfio_pfn(struct vfio_dma *dma, struct vfio_pfn *vpfn) |
| { |
| int ret = 0; |
| |
| if (atomic_dec_and_test(&vpfn->ref_count)) { |
| ret = put_pfn(vpfn->pfn, dma->prot); |
| vfio_remove_from_pfn_list(dma, vpfn); |
| } |
| return ret; |
| } |
| |
| static int vfio_lock_acct(struct task_struct *task, long npage, bool *lock_cap) |
| { |
| struct mm_struct *mm; |
| bool is_current; |
| int ret; |
| |
| if (!npage) |
| return 0; |
| |
| is_current = (task->mm == current->mm); |
| |
| mm = is_current ? task->mm : get_task_mm(task); |
| if (!mm) |
| return -ESRCH; /* process exited */ |
| |
| ret = down_write_killable(&mm->mmap_sem); |
| if (!ret) { |
| if (npage > 0) { |
| if (lock_cap ? !*lock_cap : |
| !has_capability(task, CAP_IPC_LOCK)) { |
| unsigned long limit; |
| |
| limit = task_rlimit(task, |
| RLIMIT_MEMLOCK) >> PAGE_SHIFT; |
| |
| if (mm->locked_vm + npage > limit) |
| ret = -ENOMEM; |
| } |
| } |
| |
| if (!ret) |
| mm->locked_vm += npage; |
| |
| up_write(&mm->mmap_sem); |
| } |
| |
| if (!is_current) |
| mmput(mm); |
| |
| return ret; |
| } |
| |
| /* |
| * Some mappings aren't backed by a struct page, for example an mmap'd |
| * MMIO range for our own or another device. These use a different |
| * pfn conversion and shouldn't be tracked as locked pages. |
| */ |
| static bool is_invalid_reserved_pfn(unsigned long pfn) |
| { |
| if (pfn_valid(pfn)) { |
| bool reserved; |
| struct page *tail = pfn_to_page(pfn); |
| struct page *head = compound_head(tail); |
| reserved = !!(PageReserved(head)); |
| if (head != tail) { |
| /* |
| * "head" is not a dangling pointer |
| * (compound_head takes care of that) |
| * but the hugepage may have been split |
| * from under us (and we may not hold a |
| * reference count on the head page so it can |
| * be reused before we run PageReferenced), so |
| * we've to check PageTail before returning |
| * what we just read. |
| */ |
| smp_rmb(); |
| if (PageTail(tail)) |
| return reserved; |
| } |
| return PageReserved(tail); |
| } |
| |
| return true; |
| } |
| |
| static int put_pfn(unsigned long pfn, int prot) |
| { |
| if (!is_invalid_reserved_pfn(pfn)) { |
| struct page *page = pfn_to_page(pfn); |
| if (prot & IOMMU_WRITE) |
| SetPageDirty(page); |
| put_page(page); |
| return 1; |
| } |
| return 0; |
| } |
| |
| static int vaddr_get_pfn(struct mm_struct *mm, unsigned long vaddr, |
| int prot, unsigned long *pfn) |
| { |
| struct page *page[1]; |
| struct vm_area_struct *vma; |
| int ret; |
| |
| if (mm == current->mm) { |
| ret = get_user_pages_fast(vaddr, 1, !!(prot & IOMMU_WRITE), |
| page); |
| } else { |
| unsigned int flags = 0; |
| |
| if (prot & IOMMU_WRITE) |
| flags |= FOLL_WRITE; |
| |
| down_read(&mm->mmap_sem); |
| ret = get_user_pages_remote(NULL, mm, vaddr, 1, flags, page, |
| NULL, NULL); |
| up_read(&mm->mmap_sem); |
| } |
| |
| if (ret == 1) { |
| *pfn = page_to_pfn(page[0]); |
| return 0; |
| } |
| |
| down_read(&mm->mmap_sem); |
| |
| vma = find_vma_intersection(mm, vaddr, vaddr + 1); |
| |
| if (vma && vma->vm_flags & VM_PFNMAP) { |
| *pfn = ((vaddr - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff; |
| if (is_invalid_reserved_pfn(*pfn)) |
| ret = 0; |
| } |
| |
| up_read(&mm->mmap_sem); |
| return ret; |
| } |
| |
| /* |
| * Attempt to pin pages. We really don't want to track all the pfns and |
| * the iommu can only map chunks of consecutive pfns anyway, so get the |
| * first page and all consecutive pages with the same locking. |
| */ |
| static long vfio_pin_pages_remote(struct vfio_dma *dma, unsigned long vaddr, |
| long npage, unsigned long *pfn_base, |
| bool lock_cap, unsigned long limit) |
| { |
| unsigned long pfn = 0; |
| long ret, pinned = 0, lock_acct = 0; |
| bool rsvd; |
| dma_addr_t iova = vaddr - dma->vaddr + dma->iova; |
| |
| /* This code path is only user initiated */ |
| if (!current->mm) |
| return -ENODEV; |
| |
| ret = vaddr_get_pfn(current->mm, vaddr, dma->prot, pfn_base); |
| if (ret) |
| return ret; |
| |
| pinned++; |
| rsvd = is_invalid_reserved_pfn(*pfn_base); |
| |
| /* |
| * Reserved pages aren't counted against the user, externally pinned |
| * pages are already counted against the user. |
| */ |
| if (!rsvd && !vfio_find_vpfn(dma, iova)) { |
| if (!lock_cap && current->mm->locked_vm + 1 > limit) { |
| put_pfn(*pfn_base, dma->prot); |
| pr_warn("%s: RLIMIT_MEMLOCK (%ld) exceeded\n", __func__, |
| limit << PAGE_SHIFT); |
| return -ENOMEM; |
| } |
| lock_acct++; |
| } |
| |
| if (unlikely(disable_hugepages)) |
| goto out; |
| |
| /* Lock all the consecutive pages from pfn_base */ |
| for (vaddr += PAGE_SIZE, iova += PAGE_SIZE; pinned < npage; |
| pinned++, vaddr += PAGE_SIZE, iova += PAGE_SIZE) { |
| ret = vaddr_get_pfn(current->mm, vaddr, dma->prot, &pfn); |
| if (ret) |
| break; |
| |
| if (pfn != *pfn_base + pinned || |
| rsvd != is_invalid_reserved_pfn(pfn)) { |
| put_pfn(pfn, dma->prot); |
| break; |
| } |
| |
| if (!rsvd && !vfio_find_vpfn(dma, iova)) { |
| if (!lock_cap && |
| current->mm->locked_vm + lock_acct + 1 > limit) { |
| put_pfn(pfn, dma->prot); |
| pr_warn("%s: RLIMIT_MEMLOCK (%ld) exceeded\n", |
| __func__, limit << PAGE_SHIFT); |
| ret = -ENOMEM; |
| goto unpin_out; |
| } |
| lock_acct++; |
| } |
| } |
| |
| out: |
| ret = vfio_lock_acct(current, lock_acct, &lock_cap); |
| |
| unpin_out: |
| if (ret) { |
| if (!rsvd) { |
| for (pfn = *pfn_base ; pinned ; pfn++, pinned--) |
| put_pfn(pfn, dma->prot); |
| } |
| |
| return ret; |
| } |
| |
| return pinned; |
| } |
| |
| static long vfio_unpin_pages_remote(struct vfio_dma *dma, dma_addr_t iova, |
| unsigned long pfn, long npage, |
| bool do_accounting) |
| { |
| long unlocked = 0, locked = 0; |
| long i; |
| |
| for (i = 0; i < npage; i++, iova += PAGE_SIZE) { |
| if (put_pfn(pfn++, dma->prot)) { |
| unlocked++; |
| if (vfio_find_vpfn(dma, iova)) |
| locked++; |
| } |
| } |
| |
| if (do_accounting) |
| vfio_lock_acct(dma->task, locked - unlocked, NULL); |
| |
| return unlocked; |
| } |
| |
| static int vfio_pin_page_external(struct vfio_dma *dma, unsigned long vaddr, |
| unsigned long *pfn_base, bool do_accounting) |
| { |
| struct mm_struct *mm; |
| int ret; |
| |
| mm = get_task_mm(dma->task); |
| if (!mm) |
| return -ENODEV; |
| |
| ret = vaddr_get_pfn(mm, vaddr, dma->prot, pfn_base); |
| if (!ret && do_accounting && !is_invalid_reserved_pfn(*pfn_base)) { |
| ret = vfio_lock_acct(dma->task, 1, NULL); |
| if (ret) { |
| put_pfn(*pfn_base, dma->prot); |
| if (ret == -ENOMEM) |
| pr_warn("%s: Task %s (%d) RLIMIT_MEMLOCK " |
| "(%ld) exceeded\n", __func__, |
| dma->task->comm, task_pid_nr(dma->task), |
| task_rlimit(dma->task, RLIMIT_MEMLOCK)); |
| } |
| } |
| |
| mmput(mm); |
| return ret; |
| } |
| |
| static int vfio_unpin_page_external(struct vfio_dma *dma, dma_addr_t iova, |
| bool do_accounting) |
| { |
| int unlocked; |
| struct vfio_pfn *vpfn = vfio_find_vpfn(dma, iova); |
| |
| if (!vpfn) |
| return 0; |
| |
| unlocked = vfio_iova_put_vfio_pfn(dma, vpfn); |
| |
| if (do_accounting) |
| vfio_lock_acct(dma->task, -unlocked, NULL); |
| |
| return unlocked; |
| } |
| |
| static int vfio_iommu_type1_pin_pages(void *iommu_data, |
| unsigned long *user_pfn, |
| int npage, int prot, |
| unsigned long *phys_pfn) |
| { |
| struct vfio_iommu *iommu = iommu_data; |
| int i, j, ret; |
| unsigned long remote_vaddr; |
| struct vfio_dma *dma; |
| bool do_accounting; |
| |
| if (!iommu || !user_pfn || !phys_pfn) |
| return -EINVAL; |
| |
| /* Supported for v2 version only */ |
| if (!iommu->v2) |
| return -EACCES; |
| |
| mutex_lock(&iommu->lock); |
| |
| /* Fail if notifier list is empty */ |
| if ((!iommu->external_domain) || (!iommu->notifier.head)) { |
| ret = -EINVAL; |
| goto pin_done; |
| } |
| |
| /* |
| * If iommu capable domain exist in the container then all pages are |
| * already pinned and accounted. Accouting should be done if there is no |
| * iommu capable domain in the container. |
| */ |
| do_accounting = !IS_IOMMU_CAP_DOMAIN_IN_CONTAINER(iommu); |
| |
| for (i = 0; i < npage; i++) { |
| dma_addr_t iova; |
| struct vfio_pfn *vpfn; |
| |
| iova = user_pfn[i] << PAGE_SHIFT; |
| dma = vfio_find_dma(iommu, iova, PAGE_SIZE); |
| if (!dma) { |
| ret = -EINVAL; |
| goto pin_unwind; |
| } |
| |
| if ((dma->prot & prot) != prot) { |
| ret = -EPERM; |
| goto pin_unwind; |
| } |
| |
| vpfn = vfio_iova_get_vfio_pfn(dma, iova); |
| if (vpfn) { |
| phys_pfn[i] = vpfn->pfn; |
| continue; |
| } |
| |
| remote_vaddr = dma->vaddr + iova - dma->iova; |
| ret = vfio_pin_page_external(dma, remote_vaddr, &phys_pfn[i], |
| do_accounting); |
| if (ret) |
| goto pin_unwind; |
| |
| ret = vfio_add_to_pfn_list(dma, iova, phys_pfn[i]); |
| if (ret) { |
| vfio_unpin_page_external(dma, iova, do_accounting); |
| goto pin_unwind; |
| } |
| } |
| |
| ret = i; |
| goto pin_done; |
| |
| pin_unwind: |
| phys_pfn[i] = 0; |
| for (j = 0; j < i; j++) { |
| dma_addr_t iova; |
| |
| iova = user_pfn[j] << PAGE_SHIFT; |
| dma = vfio_find_dma(iommu, iova, PAGE_SIZE); |
| vfio_unpin_page_external(dma, iova, do_accounting); |
| phys_pfn[j] = 0; |
| } |
| pin_done: |
| mutex_unlock(&iommu->lock); |
| return ret; |
| } |
| |
| static int vfio_iommu_type1_unpin_pages(void *iommu_data, |
| unsigned long *user_pfn, |
| int npage) |
| { |
| struct vfio_iommu *iommu = iommu_data; |
| bool do_accounting; |
| int i; |
| |
| if (!iommu || !user_pfn) |
| return -EINVAL; |
| |
| /* Supported for v2 version only */ |
| if (!iommu->v2) |
| return -EACCES; |
| |
| mutex_lock(&iommu->lock); |
| |
| if (!iommu->external_domain) { |
| mutex_unlock(&iommu->lock); |
| return -EINVAL; |
| } |
| |
| do_accounting = !IS_IOMMU_CAP_DOMAIN_IN_CONTAINER(iommu); |
| for (i = 0; i < npage; i++) { |
| struct vfio_dma *dma; |
| dma_addr_t iova; |
| |
| iova = user_pfn[i] << PAGE_SHIFT; |
| dma = vfio_find_dma(iommu, iova, PAGE_SIZE); |
| if (!dma) |
| goto unpin_exit; |
| vfio_unpin_page_external(dma, iova, do_accounting); |
| } |
| |
| unpin_exit: |
| mutex_unlock(&iommu->lock); |
| return i > npage ? npage : (i > 0 ? i : -EINVAL); |
| } |
| |
| static long vfio_unmap_unpin(struct vfio_iommu *iommu, struct vfio_dma *dma, |
| bool do_accounting) |
| { |
| dma_addr_t iova = dma->iova, end = dma->iova + dma->size; |
| struct vfio_domain *domain, *d; |
| long unlocked = 0; |
| |
| if (!dma->size) |
| return 0; |
| |
| if (!IS_IOMMU_CAP_DOMAIN_IN_CONTAINER(iommu)) |
| return 0; |
| |
| /* |
| * We use the IOMMU to track the physical addresses, otherwise we'd |
| * need a much more complicated tracking system. Unfortunately that |
| * means we need to use one of the iommu domains to figure out the |
| * pfns to unpin. The rest need to be unmapped in advance so we have |
| * no iommu translations remaining when the pages are unpinned. |
| */ |
| domain = d = list_first_entry(&iommu->domain_list, |
| struct vfio_domain, next); |
| |
| list_for_each_entry_continue(d, &iommu->domain_list, next) { |
| iommu_unmap(d->domain, dma->iova, dma->size); |
| cond_resched(); |
| } |
| |
| while (iova < end) { |
| size_t unmapped, len; |
| phys_addr_t phys, next; |
| |
| phys = iommu_iova_to_phys(domain->domain, iova); |
| if (WARN_ON(!phys)) { |
| iova += PAGE_SIZE; |
| continue; |
| } |
| |
| /* |
| * To optimize for fewer iommu_unmap() calls, each of which |
| * may require hardware cache flushing, try to find the |
| * largest contiguous physical memory chunk to unmap. |
| */ |
| for (len = PAGE_SIZE; |
| !domain->fgsp && iova + len < end; len += PAGE_SIZE) { |
| next = iommu_iova_to_phys(domain->domain, iova + len); |
| if (next != phys + len) |
| break; |
| } |
| |
| unmapped = iommu_unmap(domain->domain, iova, len); |
| if (WARN_ON(!unmapped)) |
| break; |
| |
| unlocked += vfio_unpin_pages_remote(dma, iova, |
| phys >> PAGE_SHIFT, |
| unmapped >> PAGE_SHIFT, |
| false); |
| iova += unmapped; |
| |
| cond_resched(); |
| } |
| |
| dma->iommu_mapped = false; |
| if (do_accounting) { |
| vfio_lock_acct(dma->task, -unlocked, NULL); |
| return 0; |
| } |
| return unlocked; |
| } |
| |
| static void vfio_remove_dma(struct vfio_iommu *iommu, struct vfio_dma *dma) |
| { |
| vfio_unmap_unpin(iommu, dma, true); |
| vfio_unlink_dma(iommu, dma); |
| put_task_struct(dma->task); |
| kfree(dma); |
| } |
| |
| static unsigned long vfio_pgsize_bitmap(struct vfio_iommu *iommu) |
| { |
| struct vfio_domain *domain; |
| unsigned long bitmap = ULONG_MAX; |
| |
| mutex_lock(&iommu->lock); |
| list_for_each_entry(domain, &iommu->domain_list, next) |
| bitmap &= domain->domain->pgsize_bitmap; |
| mutex_unlock(&iommu->lock); |
| |
| /* |
| * In case the IOMMU supports page sizes smaller than PAGE_SIZE |
| * we pretend PAGE_SIZE is supported and hide sub-PAGE_SIZE sizes. |
| * That way the user will be able to map/unmap buffers whose size/ |
| * start address is aligned with PAGE_SIZE. Pinning code uses that |
| * granularity while iommu driver can use the sub-PAGE_SIZE size |
| * to map the buffer. |
| */ |
| if (bitmap & ~PAGE_MASK) { |
| bitmap &= PAGE_MASK; |
| bitmap |= PAGE_SIZE; |
| } |
| |
| return bitmap; |
| } |
| |
| static int vfio_dma_do_unmap(struct vfio_iommu *iommu, |
| struct vfio_iommu_type1_dma_unmap *unmap) |
| { |
| uint64_t mask; |
| struct vfio_dma *dma, *dma_last = NULL; |
| size_t unmapped = 0; |
| int ret = 0, retries = 0; |
| |
| mask = ((uint64_t)1 << __ffs(vfio_pgsize_bitmap(iommu))) - 1; |
| |
| if (unmap->iova & mask) |
| return -EINVAL; |
| if (!unmap->size || unmap->size & mask) |
| return -EINVAL; |
| |
| WARN_ON(mask & PAGE_MASK); |
| again: |
| mutex_lock(&iommu->lock); |
| |
| /* |
| * vfio-iommu-type1 (v1) - User mappings were coalesced together to |
| * avoid tracking individual mappings. This means that the granularity |
| * of the original mapping was lost and the user was allowed to attempt |
| * to unmap any range. Depending on the contiguousness of physical |
| * memory and page sizes supported by the IOMMU, arbitrary unmaps may |
| * or may not have worked. We only guaranteed unmap granularity |
| * matching the original mapping; even though it was untracked here, |
| * the original mappings are reflected in IOMMU mappings. This |
| * resulted in a couple unusual behaviors. First, if a range is not |
| * able to be unmapped, ex. a set of 4k pages that was mapped as a |
| * 2M hugepage into the IOMMU, the unmap ioctl returns success but with |
| * a zero sized unmap. Also, if an unmap request overlaps the first |
| * address of a hugepage, the IOMMU will unmap the entire hugepage. |
| * This also returns success and the returned unmap size reflects the |
| * actual size unmapped. |
| * |
| * We attempt to maintain compatibility with this "v1" interface, but |
| * we take control out of the hands of the IOMMU. Therefore, an unmap |
| * request offset from the beginning of the original mapping will |
| * return success with zero sized unmap. And an unmap request covering |
| * the first iova of mapping will unmap the entire range. |
| * |
| * The v2 version of this interface intends to be more deterministic. |
| * Unmap requests must fully cover previous mappings. Multiple |
| * mappings may still be unmaped by specifying large ranges, but there |
| * must not be any previous mappings bisected by the range. An error |
| * will be returned if these conditions are not met. The v2 interface |
| * will only return success and a size of zero if there were no |
| * mappings within the range. |
| */ |
| if (iommu->v2) { |
| dma = vfio_find_dma(iommu, unmap->iova, 1); |
| if (dma && dma->iova != unmap->iova) { |
| ret = -EINVAL; |
| goto unlock; |
| } |
| dma = vfio_find_dma(iommu, unmap->iova + unmap->size - 1, 0); |
| if (dma && dma->iova + dma->size != unmap->iova + unmap->size) { |
| ret = -EINVAL; |
| goto unlock; |
| } |
| } |
| |
| while ((dma = vfio_find_dma(iommu, unmap->iova, unmap->size))) { |
| if (!iommu->v2 && unmap->iova > dma->iova) |
| break; |
| /* |
| * Task with same address space who mapped this iova range is |
| * allowed to unmap the iova range. |
| */ |
| if (dma->task->mm != current->mm) |
| break; |
| |
| if (!RB_EMPTY_ROOT(&dma->pfn_list)) { |
| struct vfio_iommu_type1_dma_unmap nb_unmap; |
| |
| if (dma_last == dma) { |
| BUG_ON(++retries > 10); |
| } else { |
| dma_last = dma; |
| retries = 0; |
| } |
| |
| nb_unmap.iova = dma->iova; |
| nb_unmap.size = dma->size; |
| |
| /* |
| * Notify anyone (mdev vendor drivers) to invalidate and |
| * unmap iovas within the range we're about to unmap. |
| * Vendor drivers MUST unpin pages in response to an |
| * invalidation. |
| */ |
| mutex_unlock(&iommu->lock); |
| blocking_notifier_call_chain(&iommu->notifier, |
| VFIO_IOMMU_NOTIFY_DMA_UNMAP, |
| &nb_unmap); |
| goto again; |
| } |
| unmapped += dma->size; |
| vfio_remove_dma(iommu, dma); |
| } |
| |
| unlock: |
| mutex_unlock(&iommu->lock); |
| |
| /* Report how much was unmapped */ |
| unmap->size = unmapped; |
| |
| return ret; |
| } |
| |
| /* |
| * Turns out AMD IOMMU has a page table bug where it won't map large pages |
| * to a region that previously mapped smaller pages. This should be fixed |
| * soon, so this is just a temporary workaround to break mappings down into |
| * PAGE_SIZE. Better to map smaller pages than nothing. |
| */ |
| static int map_try_harder(struct vfio_domain *domain, dma_addr_t iova, |
| unsigned long pfn, long npage, int prot) |
| { |
| long i; |
| int ret = 0; |
| |
| for (i = 0; i < npage; i++, pfn++, iova += PAGE_SIZE) { |
| ret = iommu_map(domain->domain, iova, |
| (phys_addr_t)pfn << PAGE_SHIFT, |
| PAGE_SIZE, prot | domain->prot); |
| if (ret) |
| break; |
| } |
| |
| for (; i < npage && i > 0; i--, iova -= PAGE_SIZE) |
| iommu_unmap(domain->domain, iova, PAGE_SIZE); |
| |
| return ret; |
| } |
| |
| static int vfio_iommu_map(struct vfio_iommu *iommu, dma_addr_t iova, |
| unsigned long pfn, long npage, int prot) |
| { |
| struct vfio_domain *d; |
| int ret; |
| |
| list_for_each_entry(d, &iommu->domain_list, next) { |
| ret = iommu_map(d->domain, iova, (phys_addr_t)pfn << PAGE_SHIFT, |
| npage << PAGE_SHIFT, prot | d->prot); |
| if (ret) { |
| if (ret != -EBUSY || |
| map_try_harder(d, iova, pfn, npage, prot)) |
| goto unwind; |
| } |
| |
| cond_resched(); |
| } |
| |
| return 0; |
| |
| unwind: |
| list_for_each_entry_continue_reverse(d, &iommu->domain_list, next) |
| iommu_unmap(d->domain, iova, npage << PAGE_SHIFT); |
| |
| return ret; |
| } |
| |
| static int vfio_pin_map_dma(struct vfio_iommu *iommu, struct vfio_dma *dma, |
| size_t map_size) |
| { |
| dma_addr_t iova = dma->iova; |
| unsigned long vaddr = dma->vaddr; |
| size_t size = map_size; |
| long npage; |
| unsigned long pfn, limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; |
| bool lock_cap = capable(CAP_IPC_LOCK); |
| int ret = 0; |
| |
| while (size) { |
| /* Pin a contiguous chunk of memory */ |
| npage = vfio_pin_pages_remote(dma, vaddr + dma->size, |
| size >> PAGE_SHIFT, &pfn, |
| lock_cap, limit); |
| if (npage <= 0) { |
| WARN_ON(!npage); |
| ret = (int)npage; |
| break; |
| } |
| |
| /* Map it! */ |
| ret = vfio_iommu_map(iommu, iova + dma->size, pfn, npage, |
| dma->prot); |
| if (ret) { |
| vfio_unpin_pages_remote(dma, iova + dma->size, pfn, |
| npage, true); |
| break; |
| } |
| |
| size -= npage << PAGE_SHIFT; |
| dma->size += npage << PAGE_SHIFT; |
| } |
| |
| dma->iommu_mapped = true; |
| |
| if (ret) |
| vfio_remove_dma(iommu, dma); |
| |
| return ret; |
| } |
| |
| static int vfio_dma_do_map(struct vfio_iommu *iommu, |
| struct vfio_iommu_type1_dma_map *map) |
| { |
| dma_addr_t iova = map->iova; |
| unsigned long vaddr = map->vaddr; |
| size_t size = map->size; |
| int ret = 0, prot = 0; |
| uint64_t mask; |
| struct vfio_dma *dma; |
| |
| /* Verify that none of our __u64 fields overflow */ |
| if (map->size != size || map->vaddr != vaddr || map->iova != iova) |
| return -EINVAL; |
| |
| mask = ((uint64_t)1 << __ffs(vfio_pgsize_bitmap(iommu))) - 1; |
| |
| WARN_ON(mask & PAGE_MASK); |
| |
| /* READ/WRITE from device perspective */ |
| if (map->flags & VFIO_DMA_MAP_FLAG_WRITE) |
| prot |= IOMMU_WRITE; |
| if (map->flags & VFIO_DMA_MAP_FLAG_READ) |
| prot |= IOMMU_READ; |
| |
| if (!prot || !size || (size | iova | vaddr) & mask) |
| return -EINVAL; |
| |
| /* Don't allow IOVA or virtual address wrap */ |
| if (iova + size - 1 < iova || vaddr + size - 1 < vaddr) |
| return -EINVAL; |
| |
| mutex_lock(&iommu->lock); |
| |
| if (vfio_find_dma(iommu, iova, size)) { |
| ret = -EEXIST; |
| goto out_unlock; |
| } |
| |
| dma = kzalloc(sizeof(*dma), GFP_KERNEL); |
| if (!dma) { |
| ret = -ENOMEM; |
| goto out_unlock; |
| } |
| |
| dma->iova = iova; |
| dma->vaddr = vaddr; |
| dma->prot = prot; |
| get_task_struct(current); |
| dma->task = current; |
| dma->pfn_list = RB_ROOT; |
| |
| /* Insert zero-sized and grow as we map chunks of it */ |
| vfio_link_dma(iommu, dma); |
| |
| /* Don't pin and map if container doesn't contain IOMMU capable domain*/ |
| if (!IS_IOMMU_CAP_DOMAIN_IN_CONTAINER(iommu)) |
| dma->size = size; |
| else |
| ret = vfio_pin_map_dma(iommu, dma, size); |
| |
| out_unlock: |
| mutex_unlock(&iommu->lock); |
| return ret; |
| } |
| |
| static int vfio_bus_type(struct device *dev, void *data) |
| { |
| struct bus_type **bus = data; |
| |
| if (*bus && *bus != dev->bus) |
| return -EINVAL; |
| |
| *bus = dev->bus; |
| |
| return 0; |
| } |
| |
| static int vfio_iommu_replay(struct vfio_iommu *iommu, |
| struct vfio_domain *domain) |
| { |
| struct vfio_domain *d; |
| struct rb_node *n; |
| unsigned long limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; |
| bool lock_cap = capable(CAP_IPC_LOCK); |
| int ret; |
| |
| /* Arbitrarily pick the first domain in the list for lookups */ |
| d = list_first_entry(&iommu->domain_list, struct vfio_domain, next); |
| n = rb_first(&iommu->dma_list); |
| |
| for (; n; n = rb_next(n)) { |
| struct vfio_dma *dma; |
| dma_addr_t iova; |
| |
| dma = rb_entry(n, struct vfio_dma, node); |
| iova = dma->iova; |
| |
| while (iova < dma->iova + dma->size) { |
| phys_addr_t phys; |
| size_t size; |
| |
| if (dma->iommu_mapped) { |
| phys_addr_t p; |
| dma_addr_t i; |
| |
| phys = iommu_iova_to_phys(d->domain, iova); |
| |
| if (WARN_ON(!phys)) { |
| iova += PAGE_SIZE; |
| continue; |
| } |
| |
| size = PAGE_SIZE; |
| p = phys + size; |
| i = iova + size; |
| while (i < dma->iova + dma->size && |
| p == iommu_iova_to_phys(d->domain, i)) { |
| size += PAGE_SIZE; |
| p += PAGE_SIZE; |
| i += PAGE_SIZE; |
| } |
| } else { |
| unsigned long pfn; |
| unsigned long vaddr = dma->vaddr + |
| (iova - dma->iova); |
| size_t n = dma->iova + dma->size - iova; |
| long npage; |
| |
| npage = vfio_pin_pages_remote(dma, vaddr, |
| n >> PAGE_SHIFT, |
| &pfn, lock_cap, |
| limit); |
| if (npage <= 0) { |
| WARN_ON(!npage); |
| ret = (int)npage; |
| return ret; |
| } |
| |
| phys = pfn << PAGE_SHIFT; |
| size = npage << PAGE_SHIFT; |
| } |
| |
| ret = iommu_map(domain->domain, iova, phys, |
| size, dma->prot | domain->prot); |
| if (ret) |
| return ret; |
| |
| iova += size; |
| } |
| dma->iommu_mapped = true; |
| } |
| return 0; |
| } |
| |
| /* |
| * We change our unmap behavior slightly depending on whether the IOMMU |
| * supports fine-grained superpages. IOMMUs like AMD-Vi will use a superpage |
| * for practically any contiguous power-of-two mapping we give it. This means |
| * we don't need to look for contiguous chunks ourselves to make unmapping |
| * more efficient. On IOMMUs with coarse-grained super pages, like Intel VT-d |
| * with discrete 2M/1G/512G/1T superpages, identifying contiguous chunks |
| * significantly boosts non-hugetlbfs mappings and doesn't seem to hurt when |
| * hugetlbfs is in use. |
| */ |
| static void vfio_test_domain_fgsp(struct vfio_domain *domain) |
| { |
| struct page *pages; |
| int ret, order = get_order(PAGE_SIZE * 2); |
| |
| pages = alloc_pages(GFP_KERNEL | __GFP_ZERO, order); |
| if (!pages) |
| return; |
| |
| ret = iommu_map(domain->domain, 0, page_to_phys(pages), PAGE_SIZE * 2, |
| IOMMU_READ | IOMMU_WRITE | domain->prot); |
| if (!ret) { |
| size_t unmapped = iommu_unmap(domain->domain, 0, PAGE_SIZE); |
| |
| if (unmapped == PAGE_SIZE) |
| iommu_unmap(domain->domain, PAGE_SIZE, PAGE_SIZE); |
| else |
| domain->fgsp = true; |
| } |
| |
| __free_pages(pages, order); |
| } |
| |
| static struct vfio_group *find_iommu_group(struct vfio_domain *domain, |
| struct iommu_group *iommu_group) |
| { |
| struct vfio_group *g; |
| |
| list_for_each_entry(g, &domain->group_list, next) { |
| if (g->iommu_group == iommu_group) |
| return g; |
| } |
| |
| return NULL; |
| } |
| |
| static bool vfio_iommu_has_sw_msi(struct iommu_group *group, phys_addr_t *base) |
| { |
| struct list_head group_resv_regions; |
| struct iommu_resv_region *region, *next; |
| bool ret = false; |
| |
| INIT_LIST_HEAD(&group_resv_regions); |
| iommu_get_group_resv_regions(group, &group_resv_regions); |
| list_for_each_entry(region, &group_resv_regions, list) { |
| if (region->type == IOMMU_RESV_SW_MSI) { |
| *base = region->start; |
| ret = true; |
| goto out; |
| } |
| } |
| out: |
| list_for_each_entry_safe(region, next, &group_resv_regions, list) |
| kfree(region); |
| return ret; |
| } |
| |
| static int vfio_iommu_type1_attach_group(void *iommu_data, |
| struct iommu_group *iommu_group) |
| { |
| struct vfio_iommu *iommu = iommu_data; |
| struct vfio_group *group; |
| struct vfio_domain *domain, *d; |
| struct bus_type *bus = NULL, *mdev_bus; |
| int ret; |
| bool resv_msi, msi_remap; |
| phys_addr_t resv_msi_base; |
| |
| mutex_lock(&iommu->lock); |
| |
| list_for_each_entry(d, &iommu->domain_list, next) { |
| if (find_iommu_group(d, iommu_group)) { |
| mutex_unlock(&iommu->lock); |
| return -EINVAL; |
| } |
| } |
| |
| if (iommu->external_domain) { |
| if (find_iommu_group(iommu->external_domain, iommu_group)) { |
| mutex_unlock(&iommu->lock); |
| return -EINVAL; |
| } |
| } |
| |
| group = kzalloc(sizeof(*group), GFP_KERNEL); |
| domain = kzalloc(sizeof(*domain), GFP_KERNEL); |
| if (!group || !domain) { |
| ret = -ENOMEM; |
| goto out_free; |
| } |
| |
| group->iommu_group = iommu_group; |
| |
| /* Determine bus_type in order to allocate a domain */ |
| ret = iommu_group_for_each_dev(iommu_group, &bus, vfio_bus_type); |
| if (ret) |
| goto out_free; |
| |
| mdev_bus = symbol_get(mdev_bus_type); |
| |
| if (mdev_bus) { |
| if ((bus == mdev_bus) && !iommu_present(bus)) { |
| symbol_put(mdev_bus_type); |
| if (!iommu->external_domain) { |
| INIT_LIST_HEAD(&domain->group_list); |
| iommu->external_domain = domain; |
| } else |
| kfree(domain); |
| |
| list_add(&group->next, |
| &iommu->external_domain->group_list); |
| mutex_unlock(&iommu->lock); |
| return 0; |
| } |
| symbol_put(mdev_bus_type); |
| } |
| |
| domain->domain = iommu_domain_alloc(bus); |
| if (!domain->domain) { |
| ret = -EIO; |
| goto out_free; |
| } |
| |
| if (iommu->nesting) { |
| int attr = 1; |
| |
| ret = iommu_domain_set_attr(domain->domain, DOMAIN_ATTR_NESTING, |
| &attr); |
| if (ret) |
| goto out_domain; |
| } |
| |
| ret = iommu_attach_group(domain->domain, iommu_group); |
| if (ret) |
| goto out_domain; |
| |
| resv_msi = vfio_iommu_has_sw_msi(iommu_group, &resv_msi_base); |
| |
| INIT_LIST_HEAD(&domain->group_list); |
| list_add(&group->next, &domain->group_list); |
| |
| msi_remap = resv_msi ? irq_domain_check_msi_remap() : |
| iommu_capable(bus, IOMMU_CAP_INTR_REMAP); |
| |
| if (!allow_unsafe_interrupts && !msi_remap) { |
| pr_warn("%s: No interrupt remapping support. Use the module param \"allow_unsafe_interrupts\" to enable VFIO IOMMU support on this platform\n", |
| __func__); |
| ret = -EPERM; |
| goto out_detach; |
| } |
| |
| if (iommu_capable(bus, IOMMU_CAP_CACHE_COHERENCY)) |
| domain->prot |= IOMMU_CACHE; |
| |
| /* |
| * Try to match an existing compatible domain. We don't want to |
| * preclude an IOMMU driver supporting multiple bus_types and being |
| * able to include different bus_types in the same IOMMU domain, so |
| * we test whether the domains use the same iommu_ops rather than |
| * testing if they're on the same bus_type. |
| */ |
| list_for_each_entry(d, &iommu->domain_list, next) { |
| if (d->domain->ops == domain->domain->ops && |
| d->prot == domain->prot) { |
| iommu_detach_group(domain->domain, iommu_group); |
| if (!iommu_attach_group(d->domain, iommu_group)) { |
| list_add(&group->next, &d->group_list); |
| iommu_domain_free(domain->domain); |
| kfree(domain); |
| mutex_unlock(&iommu->lock); |
| return 0; |
| } |
| |
| ret = iommu_attach_group(domain->domain, iommu_group); |
| if (ret) |
| goto out_domain; |
| } |
| } |
| |
| vfio_test_domain_fgsp(domain); |
| |
| /* replay mappings on new domains */ |
| ret = vfio_iommu_replay(iommu, domain); |
| if (ret) |
| goto out_detach; |
| |
| if (resv_msi) { |
| ret = iommu_get_msi_cookie(domain->domain, resv_msi_base); |
| if (ret) |
| goto out_detach; |
| } |
| |
| list_add(&domain->next, &iommu->domain_list); |
| |
| mutex_unlock(&iommu->lock); |
| |
| return 0; |
| |
| out_detach: |
| iommu_detach_group(domain->domain, iommu_group); |
| out_domain: |
| iommu_domain_free(domain->domain); |
| out_free: |
| kfree(domain); |
| kfree(group); |
| mutex_unlock(&iommu->lock); |
| return ret; |
| } |
| |
| static void vfio_iommu_unmap_unpin_all(struct vfio_iommu *iommu) |
| { |
| struct rb_node *node; |
| |
| while ((node = rb_first(&iommu->dma_list))) |
| vfio_remove_dma(iommu, rb_entry(node, struct vfio_dma, node)); |
| } |
| |
| static void vfio_iommu_unmap_unpin_reaccount(struct vfio_iommu *iommu) |
| { |
| struct rb_node *n, *p; |
| |
| n = rb_first(&iommu->dma_list); |
| for (; n; n = rb_next(n)) { |
| struct vfio_dma *dma; |
| long locked = 0, unlocked = 0; |
| |
| dma = rb_entry(n, struct vfio_dma, node); |
| unlocked += vfio_unmap_unpin(iommu, dma, false); |
| p = rb_first(&dma->pfn_list); |
| for (; p; p = rb_next(p)) { |
| struct vfio_pfn *vpfn = rb_entry(p, struct vfio_pfn, |
| node); |
| |
| if (!is_invalid_reserved_pfn(vpfn->pfn)) |
| locked++; |
| } |
| vfio_lock_acct(dma->task, locked - unlocked, NULL); |
| } |
| } |
| |
| static void vfio_sanity_check_pfn_list(struct vfio_iommu *iommu) |
| { |
| struct rb_node *n; |
| |
| n = rb_first(&iommu->dma_list); |
| for (; n; n = rb_next(n)) { |
| struct vfio_dma *dma; |
| |
| dma = rb_entry(n, struct vfio_dma, node); |
| |
| if (WARN_ON(!RB_EMPTY_ROOT(&dma->pfn_list))) |
| break; |
| } |
| /* mdev vendor driver must unregister notifier */ |
| WARN_ON(iommu->notifier.head); |
| } |
| |
| static void vfio_iommu_type1_detach_group(void *iommu_data, |
| struct iommu_group *iommu_group) |
| { |
| struct vfio_iommu *iommu = iommu_data; |
| struct vfio_domain *domain; |
| struct vfio_group *group; |
| |
| mutex_lock(&iommu->lock); |
| |
| if (iommu->external_domain) { |
| group = find_iommu_group(iommu->external_domain, iommu_group); |
| if (group) { |
| list_del(&group->next); |
| kfree(group); |
| |
| if (list_empty(&iommu->external_domain->group_list)) { |
| vfio_sanity_check_pfn_list(iommu); |
| |
| if (!IS_IOMMU_CAP_DOMAIN_IN_CONTAINER(iommu)) |
| vfio_iommu_unmap_unpin_all(iommu); |
| |
| kfree(iommu->external_domain); |
| iommu->external_domain = NULL; |
| } |
| goto detach_group_done; |
| } |
| } |
| |
| list_for_each_entry(domain, &iommu->domain_list, next) { |
| group = find_iommu_group(domain, iommu_group); |
| if (!group) |
| continue; |
| |
| iommu_detach_group(domain->domain, iommu_group); |
| list_del(&group->next); |
| kfree(group); |
| /* |
| * Group ownership provides privilege, if the group list is |
| * empty, the domain goes away. If it's the last domain with |
| * iommu and external domain doesn't exist, then all the |
| * mappings go away too. If it's the last domain with iommu and |
| * external domain exist, update accounting |
| */ |
| if (list_empty(&domain->group_list)) { |
| if (list_is_singular(&iommu->domain_list)) { |
| if (!iommu->external_domain) |
| vfio_iommu_unmap_unpin_all(iommu); |
| else |
| vfio_iommu_unmap_unpin_reaccount(iommu); |
| } |
| iommu_domain_free(domain->domain); |
| list_del(&domain->next); |
| kfree(domain); |
| } |
| break; |
| } |
| |
| detach_group_done: |
| mutex_unlock(&iommu->lock); |
| } |
| |
| static void *vfio_iommu_type1_open(unsigned long arg) |
| { |
| struct vfio_iommu *iommu; |
| |
| iommu = kzalloc(sizeof(*iommu), GFP_KERNEL); |
| if (!iommu) |
| return ERR_PTR(-ENOMEM); |
| |
| switch (arg) { |
| case VFIO_TYPE1_IOMMU: |
| break; |
| case VFIO_TYPE1_NESTING_IOMMU: |
| iommu->nesting = true; |
| case VFIO_TYPE1v2_IOMMU: |
| iommu->v2 = true; |
| break; |
| default: |
| kfree(iommu); |
| return ERR_PTR(-EINVAL); |
| } |
| |
| INIT_LIST_HEAD(&iommu->domain_list); |
| iommu->dma_list = RB_ROOT; |
| mutex_init(&iommu->lock); |
| BLOCKING_INIT_NOTIFIER_HEAD(&iommu->notifier); |
| |
| return iommu; |
| } |
| |
| static void vfio_release_domain(struct vfio_domain *domain, bool external) |
| { |
| struct vfio_group *group, *group_tmp; |
| |
| list_for_each_entry_safe(group, group_tmp, |
| &domain->group_list, next) { |
| if (!external) |
| iommu_detach_group(domain->domain, group->iommu_group); |
| list_del(&group->next); |
| kfree(group); |
| } |
| |
| if (!external) |
| iommu_domain_free(domain->domain); |
| } |
| |
| static void vfio_iommu_type1_release(void *iommu_data) |
| { |
| struct vfio_iommu *iommu = iommu_data; |
| struct vfio_domain *domain, *domain_tmp; |
| |
| if (iommu->external_domain) { |
| vfio_release_domain(iommu->external_domain, true); |
| vfio_sanity_check_pfn_list(iommu); |
| kfree(iommu->external_domain); |
| } |
| |
| vfio_iommu_unmap_unpin_all(iommu); |
| |
| list_for_each_entry_safe(domain, domain_tmp, |
| &iommu->domain_list, next) { |
| vfio_release_domain(domain, false); |
| list_del(&domain->next); |
| kfree(domain); |
| } |
| kfree(iommu); |
| } |
| |
| static int vfio_domains_have_iommu_cache(struct vfio_iommu *iommu) |
| { |
| struct vfio_domain *domain; |
| int ret = 1; |
| |
| mutex_lock(&iommu->lock); |
| list_for_each_entry(domain, &iommu->domain_list, next) { |
| if (!(domain->prot & IOMMU_CACHE)) { |
| ret = 0; |
| break; |
| } |
| } |
| mutex_unlock(&iommu->lock); |
| |
| return ret; |
| } |
| |
| static long vfio_iommu_type1_ioctl(void *iommu_data, |
| unsigned int cmd, unsigned long arg) |
| { |
| struct vfio_iommu *iommu = iommu_data; |
| unsigned long minsz; |
| |
| if (cmd == VFIO_CHECK_EXTENSION) { |
| switch (arg) { |
| case VFIO_TYPE1_IOMMU: |
| case VFIO_TYPE1v2_IOMMU: |
| case VFIO_TYPE1_NESTING_IOMMU: |
| return 1; |
| case VFIO_DMA_CC_IOMMU: |
| if (!iommu) |
| return 0; |
| return vfio_domains_have_iommu_cache(iommu); |
| default: |
| return 0; |
| } |
| } else if (cmd == VFIO_IOMMU_GET_INFO) { |
| struct vfio_iommu_type1_info info; |
| |
| minsz = offsetofend(struct vfio_iommu_type1_info, iova_pgsizes); |
| |
| if (copy_from_user(&info, (void __user *)arg, minsz)) |
| return -EFAULT; |
| |
| if (info.argsz < minsz) |
| return -EINVAL; |
| |
| info.flags = VFIO_IOMMU_INFO_PGSIZES; |
| |
| info.iova_pgsizes = vfio_pgsize_bitmap(iommu); |
| |
| return copy_to_user((void __user *)arg, &info, minsz) ? |
| -EFAULT : 0; |
| |
| } else if (cmd == VFIO_IOMMU_MAP_DMA) { |
| struct vfio_iommu_type1_dma_map map; |
| uint32_t mask = VFIO_DMA_MAP_FLAG_READ | |
| VFIO_DMA_MAP_FLAG_WRITE; |
| |
| minsz = offsetofend(struct vfio_iommu_type1_dma_map, size); |
| |
| if (copy_from_user(&map, (void __user *)arg, minsz)) |
| return -EFAULT; |
| |
| if (map.argsz < minsz || map.flags & ~mask) |
| return -EINVAL; |
| |
| return vfio_dma_do_map(iommu, &map); |
| |
| } else if (cmd == VFIO_IOMMU_UNMAP_DMA) { |
| struct vfio_iommu_type1_dma_unmap unmap; |
| long ret; |
| |
| minsz = offsetofend(struct vfio_iommu_type1_dma_unmap, size); |
| |
| if (copy_from_user(&unmap, (void __user *)arg, minsz)) |
| return -EFAULT; |
| |
| if (unmap.argsz < minsz || unmap.flags) |
| return -EINVAL; |
| |
| ret = vfio_dma_do_unmap(iommu, &unmap); |
| if (ret) |
| return ret; |
| |
| return copy_to_user((void __user *)arg, &unmap, minsz) ? |
| -EFAULT : 0; |
| } |
| |
| return -ENOTTY; |
| } |
| |
| static int vfio_iommu_type1_register_notifier(void *iommu_data, |
| unsigned long *events, |
| struct notifier_block *nb) |
| { |
| struct vfio_iommu *iommu = iommu_data; |
| |
| /* clear known events */ |
| *events &= ~VFIO_IOMMU_NOTIFY_DMA_UNMAP; |
| |
| /* refuse to register if still events remaining */ |
| if (*events) |
| return -EINVAL; |
| |
| return blocking_notifier_chain_register(&iommu->notifier, nb); |
| } |
| |
| static int vfio_iommu_type1_unregister_notifier(void *iommu_data, |
| struct notifier_block *nb) |
| { |
| struct vfio_iommu *iommu = iommu_data; |
| |
| return blocking_notifier_chain_unregister(&iommu->notifier, nb); |
| } |
| |
| static const struct vfio_iommu_driver_ops vfio_iommu_driver_ops_type1 = { |
| .name = "vfio-iommu-type1", |
| .owner = THIS_MODULE, |
| .open = vfio_iommu_type1_open, |
| .release = vfio_iommu_type1_release, |
| .ioctl = vfio_iommu_type1_ioctl, |
| .attach_group = vfio_iommu_type1_attach_group, |
| .detach_group = vfio_iommu_type1_detach_group, |
| .pin_pages = vfio_iommu_type1_pin_pages, |
| .unpin_pages = vfio_iommu_type1_unpin_pages, |
| .register_notifier = vfio_iommu_type1_register_notifier, |
| .unregister_notifier = vfio_iommu_type1_unregister_notifier, |
| }; |
| |
| static int __init vfio_iommu_type1_init(void) |
| { |
| return vfio_register_iommu_driver(&vfio_iommu_driver_ops_type1); |
| } |
| |
| static void __exit vfio_iommu_type1_cleanup(void) |
| { |
| vfio_unregister_iommu_driver(&vfio_iommu_driver_ops_type1); |
| } |
| |
| module_init(vfio_iommu_type1_init); |
| module_exit(vfio_iommu_type1_cleanup); |
| |
| MODULE_VERSION(DRIVER_VERSION); |
| MODULE_LICENSE("GPL v2"); |
| MODULE_AUTHOR(DRIVER_AUTHOR); |
| MODULE_DESCRIPTION(DRIVER_DESC); |