This VFIO IOMMU backend is designed primarily for AMD-Vi and Intel VT-d hardware, but is potentially usable by anything supporting similar mapping functionality. We arbitrarily call this a Type1 backend for lack of a better name. This backend has no IOVA or host memory mapping restrictions for the user and is optimized for relatively static mappings. Mapped areas are pinned into system memory. Signed-off-by: Alex Williamson <alex.williamson@xxxxxxxxxx> --- Documentation/ioctl/ioctl-number.txt | 2 drivers/vfio/Kconfig | 6 drivers/vfio/Makefile | 2 drivers/vfio/vfio.c | 7 drivers/vfio/vfio_iommu_type1.c | 754 ++++++++++++++++++++++++++++++++++ include/linux/vfio.h | 54 ++ 6 files changed, 823 insertions(+), 2 deletions(-) create mode 100644 drivers/vfio/vfio_iommu_type1.c diff --git a/Documentation/ioctl/ioctl-number.txt b/Documentation/ioctl/ioctl-number.txt index 89bd3c4..170d838 100644 --- a/Documentation/ioctl/ioctl-number.txt +++ b/Documentation/ioctl/ioctl-number.txt @@ -88,7 +88,7 @@ Code Seq#(hex) Include File Comments and kernel/power/user.c '8' all SNP8023 advanced NIC card <mailto:mcr@xxxxxxxxxxx> -';' 64-6F linux/vfio.h +';' 64-72 linux/vfio.h '@' 00-0F linux/radeonfb.h conflict! '@' 00-0F drivers/video/aty/aty128fb.c conflict! 'A' 00-1F linux/apm_bios.h conflict! diff --git a/drivers/vfio/Kconfig b/drivers/vfio/Kconfig index 9acb1e7..128b979 100644 --- a/drivers/vfio/Kconfig +++ b/drivers/vfio/Kconfig @@ -1,6 +1,12 @@ +config VFIO_IOMMU_TYPE1 + tristate + depends on VFIO + default n + menuconfig VFIO tristate "VFIO Non-Privileged userspace driver framework" depends on IOMMU_API + select VFIO_IOMMU_TYPE1 if X86 help VFIO provides a framework for secure userspace device drivers. See Documentation/vfio.txt for more details. diff --git a/drivers/vfio/Makefile b/drivers/vfio/Makefile index 7500a67..2398d4a 100644 --- a/drivers/vfio/Makefile +++ b/drivers/vfio/Makefile @@ -1 +1,3 @@ obj-$(CONFIG_VFIO) += vfio.o +obj-$(CONFIG_VFIO_IOMMU_TYPE1) += vfio_iommu_type1.o +obj-$(CONFIG_VFIO_PCI) += pci/ diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c index cbdd525..0c25819 100644 --- a/drivers/vfio/vfio.c +++ b/drivers/vfio/vfio.c @@ -1378,6 +1378,13 @@ static int __init vfio_init(void) pr_info(DRIVER_DESC " version: " DRIVER_VERSION "\n"); + /* + * Attempt to load known iommu-drivers. This gives us a working + * environment without the user needing to explicitly load iommu + * drivers. + */ + request_module_nowait("vfio_iommu_type1"); + return 0; err_groups_cdev: diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c new file mode 100644 index 0000000..5bb6fad --- /dev/null +++ b/drivers/vfio/vfio_iommu_type1.c @@ -0,0 +1,754 @@ +/* + * VFIO: IOMMU DMA mapping support for Type1 IOMMU + * + * Copyright (C) 2012 Red Hat, Inc. All rights reserved. + * Author: Alex Williamson <alex.williamson@xxxxxxxxxx> + * + * 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@xxxxxxxxx + * + * 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/pci.h> /* pci_bus_type */ +#include <linux/sched.h> +#include <linux/slab.h> +#include <linux/uaccess.h> +#include <linux/vfio.h> +#include <linux/workqueue.h> + +#define DRIVER_VERSION "0.2" +#define DRIVER_AUTHOR "Alex Williamson <alex.williamson@xxxxxxxxxx>" +#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."); + +struct vfio_iommu { + struct iommu_domain *domain; + struct mutex lock; + struct list_head dma_list; + struct list_head group_list; + bool cache; +}; + +struct vfio_dma { + struct list_head next; + dma_addr_t iova; /* Device address */ + unsigned long vaddr; /* Process virtual addr */ + long npage; /* Number of pages */ + int prot; /* IOMMU_READ/WRITE */ +}; + +struct vfio_group { + struct iommu_group *iommu_group; + struct list_head next; +}; + +/* + * This code handles mapping and unmapping of user data buffers + * into DMA'ble space using the IOMMU + */ + +#define NPAGE_TO_SIZE(npage) ((size_t)(npage) << PAGE_SHIFT) + +struct vwork { + struct mm_struct *mm; + long npage; + struct work_struct work; +}; + +/* delayed decrement/increment for locked_vm */ +static void vfio_lock_acct_bg(struct work_struct *work) +{ + struct vwork *vwork = container_of(work, struct vwork, work); + struct mm_struct *mm; + + mm = vwork->mm; + down_write(&mm->mmap_sem); + mm->locked_vm += vwork->npage; + up_write(&mm->mmap_sem); + mmput(mm); + kfree(vwork); +} + +static void vfio_lock_acct(long npage) +{ + struct vwork *vwork; + struct mm_struct *mm; + + if (!current->mm) + return; /* process exited */ + + if (down_write_trylock(¤t->mm->mmap_sem)) { + current->mm->locked_vm += npage; + up_write(¤t->mm->mmap_sem); + return; + } + + /* + * Couldn't get mmap_sem lock, so must setup to update + * mm->locked_vm later. If locked_vm were atomic, we + * wouldn't need this silliness + */ + vwork = kmalloc(sizeof(struct vwork), GFP_KERNEL); + if (!vwork) + return; + mm = get_task_mm(current); + if (!mm) { + kfree(vwork); + return; + } + INIT_WORK(&vwork->work, vfio_lock_acct_bg); + vwork->mm = mm; + vwork->npage = npage; + schedule_work(&vwork->work); +} + +/* + * 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_trans_head(tail); + reserved = !!(PageReserved(head)); + if (head != tail) { + /* + * "head" is not a dangling pointer + * (compound_trans_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; +} + +/* Unmap DMA region */ +static long __vfio_dma_do_unmap(struct vfio_iommu *iommu, dma_addr_t iova, + long npage, int prot) +{ + long i, unlocked = 0; + + for (i = 0; i < npage; i++, iova += PAGE_SIZE) { + unsigned long pfn; + + pfn = iommu_iova_to_phys(iommu->domain, iova) >> PAGE_SHIFT; + if (pfn) { + iommu_unmap(iommu->domain, iova, PAGE_SIZE); + unlocked += put_pfn(pfn, prot); + } + } + return unlocked; +} + +static void vfio_dma_unmap(struct vfio_iommu *iommu, dma_addr_t iova, + long npage, int prot) +{ + long unlocked; + + unlocked = __vfio_dma_do_unmap(iommu, iova, npage, prot); + vfio_lock_acct(-unlocked); +} + +static int vaddr_get_pfn(unsigned long vaddr, int prot, unsigned long *pfn) +{ + struct page *page[1]; + struct vm_area_struct *vma; + int ret = -EFAULT; + + if (get_user_pages_fast(vaddr, 1, !!(prot & IOMMU_WRITE), page) == 1) { + *pfn = page_to_pfn(page[0]); + return 0; + } + + down_read(¤t->mm->mmap_sem); + + vma = find_vma_intersection(current->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(¤t->mm->mmap_sem); + + return ret; +} + +/* Map DMA region */ +static int __vfio_dma_map(struct vfio_iommu *iommu, dma_addr_t iova, + unsigned long vaddr, long npage, int prot) +{ + dma_addr_t start = iova; + long i, locked = 0; + int ret; + + /* Verify that pages are not already mapped */ + for (i = 0; i < npage; i++, iova += PAGE_SIZE) + if (iommu_iova_to_phys(iommu->domain, iova)) + return -EBUSY; + + iova = start; + + if (iommu->cache) + prot |= IOMMU_CACHE; + + /* + * XXX We break mappings into pages and use get_user_pages_fast to + * pin the pages in memory. It's been suggested that mlock might + * provide a more efficient mechanism, but nothing prevents the + * user from munlocking the pages, which could then allow the user + * access to random host memory. We also have no guarantee from the + * IOMMU API that the iommu driver can unmap sub-pages of previous + * mappings. This means we might lose an entire range if a single + * page within it is unmapped. Single page mappings are inefficient, + * but provide the most flexibility for now. + */ + for (i = 0; i < npage; i++, iova += PAGE_SIZE, vaddr += PAGE_SIZE) { + unsigned long pfn = 0; + + ret = vaddr_get_pfn(vaddr, prot, &pfn); + if (ret) { + __vfio_dma_do_unmap(iommu, start, i, prot); + return ret; + } + + /* + * Only add actual locked pages to accounting + * XXX We're effectively marking a page locked for every + * IOVA page even though it's possible the user could be + * backing multiple IOVAs with the same vaddr. This over- + * penalizes the user process, but we currently have no + * easy way to do this properly. + */ + if (!is_invalid_reserved_pfn(pfn)) + locked++; + + ret = iommu_map(iommu->domain, iova, + (phys_addr_t)pfn << PAGE_SHIFT, + PAGE_SIZE, prot); + if (ret) { + /* Back out mappings on error */ + put_pfn(pfn, prot); + __vfio_dma_do_unmap(iommu, start, i, prot); + return ret; + } + } + vfio_lock_acct(locked); + return 0; +} + +static inline bool ranges_overlap(dma_addr_t start1, size_t size1, + dma_addr_t start2, size_t size2) +{ + if (start1 < start2) + return (start2 - start1 < size1); + else if (start2 < start1) + return (start1 - start2 < size2); + return (size1 > 0 && size2 > 0); +} + +static struct vfio_dma *vfio_find_dma(struct vfio_iommu *iommu, + dma_addr_t start, size_t size) +{ + struct vfio_dma *dma; + + list_for_each_entry(dma, &iommu->dma_list, next) { + if (ranges_overlap(dma->iova, NPAGE_TO_SIZE(dma->npage), + start, size)) + return dma; + } + return NULL; +} + +static long vfio_remove_dma_overlap(struct vfio_iommu *iommu, dma_addr_t start, + size_t size, struct vfio_dma *dma) +{ + struct vfio_dma *split; + long npage_lo, npage_hi; + + /* Existing dma region is completely covered, unmap all */ + if (start <= dma->iova && + start + size >= dma->iova + NPAGE_TO_SIZE(dma->npage)) { + vfio_dma_unmap(iommu, dma->iova, dma->npage, dma->prot); + list_del(&dma->next); + npage_lo = dma->npage; + kfree(dma); + return npage_lo; + } + + /* Overlap low address of existing range */ + if (start <= dma->iova) { + size_t overlap; + + overlap = start + size - dma->iova; + npage_lo = overlap >> PAGE_SHIFT; + + vfio_dma_unmap(iommu, dma->iova, npage_lo, dma->prot); + dma->iova += overlap; + dma->vaddr += overlap; + dma->npage -= npage_lo; + return npage_lo; + } + + /* Overlap high address of existing range */ + if (start + size >= dma->iova + NPAGE_TO_SIZE(dma->npage)) { + size_t overlap; + + overlap = dma->iova + NPAGE_TO_SIZE(dma->npage) - start; + npage_hi = overlap >> PAGE_SHIFT; + + vfio_dma_unmap(iommu, start, npage_hi, dma->prot); + dma->npage -= npage_hi; + return npage_hi; + } + + /* Split existing */ + npage_lo = (start - dma->iova) >> PAGE_SHIFT; + npage_hi = dma->npage - (size >> PAGE_SHIFT) - npage_lo; + + split = kzalloc(sizeof *split, GFP_KERNEL); + if (!split) + return -ENOMEM; + + vfio_dma_unmap(iommu, start, size >> PAGE_SHIFT, dma->prot); + + dma->npage = npage_lo; + + split->npage = npage_hi; + split->iova = start + size; + split->vaddr = dma->vaddr + NPAGE_TO_SIZE(npage_lo) + size; + split->prot = dma->prot; + list_add(&split->next, &iommu->dma_list); + return size >> PAGE_SHIFT; +} + +static int vfio_dma_do_unmap(struct vfio_iommu *iommu, + struct vfio_iommu_type1_dma_unmap *unmap) +{ + long ret = 0, npage = unmap->size >> PAGE_SHIFT; + struct vfio_dma *dma, *tmp; + uint64_t mask; + + mask = ((uint64_t)1 << __ffs(iommu->domain->ops->pgsize_bitmap)) - 1; + + if (unmap->iova & mask) + return -EINVAL; + if (unmap->size & mask) + return -EINVAL; + + /* XXX We still break these down into PAGE_SIZE */ + WARN_ON(mask & PAGE_MASK); + + mutex_lock(&iommu->lock); + + list_for_each_entry_safe(dma, tmp, &iommu->dma_list, next) { + if (ranges_overlap(dma->iova, NPAGE_TO_SIZE(dma->npage), + unmap->iova, unmap->size)) { + ret = vfio_remove_dma_overlap(iommu, unmap->iova, + unmap->size, dma); + if (ret > 0) + npage -= ret; + if (ret < 0 || npage == 0) + break; + } + } + mutex_unlock(&iommu->lock); + return ret > 0 ? 0 : (int)ret; +} + +static int vfio_dma_do_map(struct vfio_iommu *iommu, + struct vfio_iommu_type1_dma_map *map) +{ + struct vfio_dma *dma, *pdma = NULL; + dma_addr_t iova = map->iova; + unsigned long locked, lock_limit, vaddr = map->vaddr; + size_t size = map->size; + int ret = 0, prot = 0; + uint64_t mask; + long npage; + + mask = ((uint64_t)1 << __ffs(iommu->domain->ops->pgsize_bitmap)) - 1; + + /* 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) + return -EINVAL; /* No READ/WRITE? */ + + if (vaddr & mask) + return -EINVAL; + if (iova & mask) + return -EINVAL; + if (size & mask) + return -EINVAL; + + /* XXX We still break these down into PAGE_SIZE */ + WARN_ON(mask & PAGE_MASK); + + /* Don't allow IOVA wrap */ + if (iova + size && iova + size < iova) + return -EINVAL; + + /* Don't allow virtual address wrap */ + if (vaddr + size && vaddr + size < vaddr) + return -EINVAL; + + npage = size >> PAGE_SHIFT; + if (!npage) + return -EINVAL; + + mutex_lock(&iommu->lock); + + if (vfio_find_dma(iommu, iova, size)) { + ret = -EBUSY; + goto out_lock; + } + + /* account for locked pages */ + locked = current->mm->locked_vm + npage; + lock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; + if (locked > lock_limit && !capable(CAP_IPC_LOCK)) { + printk(KERN_WARNING "%s: RLIMIT_MEMLOCK (%ld) exceeded\n", + __func__, rlimit(RLIMIT_MEMLOCK)); + ret = -ENOMEM; + goto out_lock; + } + + ret = __vfio_dma_map(iommu, iova, vaddr, npage, prot); + if (ret) + goto out_lock; + + /* Check if we abut a region below - nothing below 0 */ + if (iova) { + dma = vfio_find_dma(iommu, iova - 1, 1); + if (dma && dma->prot == prot && + dma->vaddr + NPAGE_TO_SIZE(dma->npage) == vaddr) { + + dma->npage += npage; + iova = dma->iova; + vaddr = dma->vaddr; + npage = dma->npage; + size = NPAGE_TO_SIZE(npage); + + pdma = dma; + } + } + + /* Check if we abut a region above - nothing above ~0 + 1 */ + if (iova + size) { + dma = vfio_find_dma(iommu, iova + size, 1); + if (dma && dma->prot == prot && + dma->vaddr == vaddr + size) { + + dma->npage += npage; + dma->iova = iova; + dma->vaddr = vaddr; + + /* + * If merged above and below, remove previously + * merged entry. New entry covers it. + */ + if (pdma) { + list_del(&pdma->next); + kfree(pdma); + } + pdma = dma; + } + } + + /* Isolated, new region */ + if (!pdma) { + dma = kzalloc(sizeof *dma, GFP_KERNEL); + if (!dma) { + ret = -ENOMEM; + vfio_dma_unmap(iommu, iova, npage, prot); + goto out_lock; + } + + dma->npage = npage; + dma->iova = iova; + dma->vaddr = vaddr; + dma->prot = prot; + list_add(&dma->next, &iommu->dma_list); + } + +out_lock: + mutex_unlock(&iommu->lock); + 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, *tmp; + int ret; + + group = kzalloc(sizeof(*group), GFP_KERNEL); + if (!group) + return -ENOMEM; + + mutex_lock(&iommu->lock); + + list_for_each_entry(tmp, &iommu->group_list, next) { + if (tmp->iommu_group == iommu_group) { + mutex_unlock(&iommu->lock); + kfree(group); + return -EINVAL; + } + } + + /* + * TODO: Domain have capabilities that might change as we add + * groups (see iommu->cache, currently never set). Check for + * them and potentially disallow groups to be attached when it + * would change capabilities (ugh). + */ + ret = iommu_attach_group(iommu->domain, iommu_group); + if (ret) { + mutex_unlock(&iommu->lock); + kfree(group); + return ret; + } + + group->iommu_group = iommu_group; + list_add(&group->next, &iommu->group_list); + + mutex_unlock(&iommu->lock); + + return 0; +} + +static void vfio_iommu_type1_detach_group(void *iommu_data, + struct iommu_group *iommu_group) +{ + struct vfio_iommu *iommu = iommu_data; + struct vfio_group *group; + + mutex_lock(&iommu->lock); + + list_for_each_entry(group, &iommu->group_list, next) { + if (group->iommu_group == iommu_group) { + iommu_detach_group(iommu->domain, iommu_group); + list_del(&group->next); + kfree(group); + break; + } + } + + mutex_unlock(&iommu->lock); +} + +static void *vfio_iommu_type1_open(unsigned long arg) +{ + struct vfio_iommu *iommu; + + if (arg != VFIO_TYPE1_IOMMU) + return ERR_PTR(-EINVAL); + + iommu = kzalloc(sizeof(*iommu), GFP_KERNEL); + if (!iommu) + return ERR_PTR(-ENOMEM); + + INIT_LIST_HEAD(&iommu->group_list); + INIT_LIST_HEAD(&iommu->dma_list); + mutex_init(&iommu->lock); + + /* + * Wish we didn't have to know about bus_type here. + */ + iommu->domain = iommu_domain_alloc(&pci_bus_type); + if (!iommu->domain) { + kfree(iommu); + return ERR_PTR(-EIO); + } + + /* + * Wish we could specify required capabilities rather than create + * a domain, see what comes out and hope it doesn't change along + * the way. Fortunately we know interrupt remapping is global for + * our iommus. + */ + if (!allow_unsafe_interrupts && + !iommu_domain_has_cap(iommu->domain, IOMMU_CAP_INTR_REMAP)) { + printk(KERN_WARNING + "%s: No interrupt remapping support. Use the module param \"allow_unsafe_interrupts\" to enable VFIO IOMMU support on this platform\n", + __func__); + iommu_domain_free(iommu->domain); + kfree(iommu); + return ERR_PTR(-EPERM); + } + + return iommu; +} + +static void vfio_iommu_type1_release(void *iommu_data) +{ + struct vfio_iommu *iommu = iommu_data; + struct vfio_group *group, *group_tmp; + struct vfio_dma *dma, *dma_tmp; + + list_for_each_entry_safe(group, group_tmp, &iommu->group_list, next) { + iommu_detach_group(iommu->domain, group->iommu_group); + list_del(&group->next); + kfree(group); + } + + list_for_each_entry_safe(dma, dma_tmp, &iommu->dma_list, next) { + vfio_dma_unmap(iommu, dma->iova, dma->npage, dma->prot); + list_del(&dma->next); + kfree(dma); + } + + iommu_domain_free(iommu->domain); + iommu->domain = NULL; + kfree(iommu); +} + +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: + return 1; + 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 = 0; + + info.iova_pgsizes = iommu->domain->ops->pgsize_bitmap; + + return copy_to_user((void __user *)arg, &info, minsz); + + } 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; + + 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; + + return vfio_dma_do_unmap(iommu, &unmap); + } + + return -ENOTTY; +} + +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, +}; + +static int __init vfio_iommu_type1_init(void) +{ + if (!iommu_present(&pci_bus_type)) + return -ENODEV; + + 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); diff --git a/include/linux/vfio.h b/include/linux/vfio.h index a586f6b..43c58b2 100644 --- a/include/linux/vfio.h +++ b/include/linux/vfio.h @@ -98,7 +98,7 @@ extern void vfio_unregister_iommu_driver( /* Extensions */ -/* None yet */ +#define VFIO_TYPE1_IOMMU 1 /* * The IOCTL interface is designed for extensibility by embedding the @@ -364,4 +364,56 @@ struct vfio_irq_set { */ #define VFIO_DEVICE_RESET _IO(VFIO_TYPE, VFIO_BASE + 11) +/* -------- API for Type1 VFIO IOMMU -------- */ + +/** + * VFIO_IOMMU_GET_INFO - _IOR(VFIO_TYPE, VFIO_BASE + 12, struct vfio_iommu_info) + * + * Retrieve information about the IOMMU object. Fills in provided + * struct vfio_iommu_info. Caller sets argsz. + * + * XXX Should we do these by CHECK_EXTENSION too? + */ +struct vfio_iommu_type1_info { + __u32 argsz; + __u32 flags; +#define VFIO_IOMMU_INFO_PGSIZES (1 << 0) /* supported page sizes info */ + __u64 iova_pgsizes; /* Bitmap of supported page sizes */ +}; + +#define VFIO_IOMMU_GET_INFO _IO(VFIO_TYPE, VFIO_BASE + 12) + +/** + * VFIO_IOMMU_MAP_DMA - _IOW(VFIO_TYPE, VFIO_BASE + 13, struct vfio_dma_map) + * + * Map process virtual addresses to IO virtual addresses using the + * provided struct vfio_dma_map. Caller sets argsz. READ &/ WRITE required. + */ +struct vfio_iommu_type1_dma_map { + __u32 argsz; + __u32 flags; +#define VFIO_DMA_MAP_FLAG_READ (1 << 0) /* readable from device */ +#define VFIO_DMA_MAP_FLAG_WRITE (1 << 1) /* writable from device */ + __u64 vaddr; /* Process virtual address */ + __u64 iova; /* IO virtual address */ + __u64 size; /* Size of mapping (bytes) */ +}; + +#define VFIO_IOMMU_MAP_DMA _IO(VFIO_TYPE, VFIO_BASE + 13) + +/** + * VFIO_IOMMU_UNMAP_DMA - _IOW(VFIO_TYPE, VFIO_BASE + 14, struct vfio_dma_unmap) + * + * Unmap IO virtual addresses using the provided struct vfio_dma_unmap. + * Caller sets argsz. + */ +struct vfio_iommu_type1_dma_unmap { + __u32 argsz; + __u32 flags; + __u64 iova; /* IO virtual address */ + __u64 size; /* Size of mapping (bytes) */ +}; + +#define VFIO_IOMMU_UNMAP_DMA _IO(VFIO_TYPE, VFIO_BASE + 14) + #endif /* VFIO_H */ -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
