vfio: Type1 IOMMU implementation
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@redhat.com>
This commit is contained in:
Alex Williamson
Родитель
4a5b2a20ec
Коммит
73fa0d10d0
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@ -1,6 +1,12 @@
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config VFIO_IOMMU_TYPE1
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tristate
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depends on VFIO
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default n
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menuconfig VFIO
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menuconfig VFIO
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tristate "VFIO Non-Privileged userspace driver framework"
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tristate "VFIO Non-Privileged userspace driver framework"
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depends on IOMMU_API
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depends on IOMMU_API
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select VFIO_IOMMU_TYPE1 if X86
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help
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help
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VFIO provides a framework for secure userspace device drivers.
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VFIO provides a framework for secure userspace device drivers.
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See Documentation/vfio.txt for more details.
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See Documentation/vfio.txt for more details.
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@ -1 +1,3 @@
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obj-$(CONFIG_VFIO) += vfio.o
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obj-$(CONFIG_VFIO) += vfio.o
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obj-$(CONFIG_VFIO_IOMMU_TYPE1) += vfio_iommu_type1.o
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obj-$(CONFIG_VFIO_PCI) += pci/
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@ -1376,6 +1376,13 @@ static int __init vfio_init(void)
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pr_info(DRIVER_DESC " version: " DRIVER_VERSION "\n");
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pr_info(DRIVER_DESC " version: " DRIVER_VERSION "\n");
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/*
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* Attempt to load known iommu-drivers. This gives us a working
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* environment without the user needing to explicitly load iommu
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* drivers.
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*/
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request_module_nowait("vfio_iommu_type1");
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return 0;
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return 0;
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err_groups_cdev:
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err_groups_cdev:
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@ -0,0 +1,753 @@
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/*
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* VFIO: IOMMU DMA mapping support for Type1 IOMMU
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*
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* Copyright (C) 2012 Red Hat, Inc. All rights reserved.
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* Author: Alex Williamson <alex.williamson@redhat.com>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*
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* Derived from original vfio:
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* Copyright 2010 Cisco Systems, Inc. All rights reserved.
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* Author: Tom Lyon, pugs@cisco.com
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*
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* We arbitrarily define a Type1 IOMMU as one matching the below code.
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* It could be called the x86 IOMMU as it's designed for AMD-Vi & Intel
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* VT-d, but that makes it harder to re-use as theoretically anyone
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* implementing a similar IOMMU could make use of this. We expect the
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* IOMMU to support the IOMMU API and have few to no restrictions around
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* the IOVA range that can be mapped. The Type1 IOMMU is currently
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* optimized for relatively static mappings of a userspace process with
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* userpsace pages pinned into memory. We also assume devices and IOMMU
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* domains are PCI based as the IOMMU API is still centered around a
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* device/bus interface rather than a group interface.
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*/
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#include <linux/compat.h>
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#include <linux/device.h>
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#include <linux/fs.h>
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#include <linux/iommu.h>
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#include <linux/module.h>
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#include <linux/mm.h>
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#include <linux/pci.h> /* pci_bus_type */
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#include <linux/sched.h>
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#include <linux/slab.h>
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#include <linux/uaccess.h>
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#include <linux/vfio.h>
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#include <linux/workqueue.h>
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#define DRIVER_VERSION "0.2"
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#define DRIVER_AUTHOR "Alex Williamson <alex.williamson@redhat.com>"
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#define DRIVER_DESC "Type1 IOMMU driver for VFIO"
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static bool allow_unsafe_interrupts;
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module_param_named(allow_unsafe_interrupts,
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allow_unsafe_interrupts, bool, S_IRUGO | S_IWUSR);
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MODULE_PARM_DESC(allow_unsafe_interrupts,
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"Enable VFIO IOMMU support for on platforms without interrupt remapping support.");
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struct vfio_iommu {
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struct iommu_domain *domain;
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struct mutex lock;
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struct list_head dma_list;
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struct list_head group_list;
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bool cache;
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};
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struct vfio_dma {
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struct list_head next;
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dma_addr_t iova; /* Device address */
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unsigned long vaddr; /* Process virtual addr */
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long npage; /* Number of pages */
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int prot; /* IOMMU_READ/WRITE */
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};
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struct vfio_group {
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struct iommu_group *iommu_group;
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struct list_head next;
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};
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/*
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* This code handles mapping and unmapping of user data buffers
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* into DMA'ble space using the IOMMU
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*/
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#define NPAGE_TO_SIZE(npage) ((size_t)(npage) << PAGE_SHIFT)
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struct vwork {
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struct mm_struct *mm;
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long npage;
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struct work_struct work;
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};
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/* delayed decrement/increment for locked_vm */
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static void vfio_lock_acct_bg(struct work_struct *work)
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{
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struct vwork *vwork = container_of(work, struct vwork, work);
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struct mm_struct *mm;
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mm = vwork->mm;
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down_write(&mm->mmap_sem);
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mm->locked_vm += vwork->npage;
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up_write(&mm->mmap_sem);
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mmput(mm);
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kfree(vwork);
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}
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static void vfio_lock_acct(long npage)
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{
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struct vwork *vwork;
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struct mm_struct *mm;
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if (!current->mm)
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return; /* process exited */
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if (down_write_trylock(¤t->mm->mmap_sem)) {
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current->mm->locked_vm += npage;
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up_write(¤t->mm->mmap_sem);
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return;
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}
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/*
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* Couldn't get mmap_sem lock, so must setup to update
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* mm->locked_vm later. If locked_vm were atomic, we
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* wouldn't need this silliness
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*/
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vwork = kmalloc(sizeof(struct vwork), GFP_KERNEL);
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if (!vwork)
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return;
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mm = get_task_mm(current);
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if (!mm) {
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kfree(vwork);
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return;
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}
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INIT_WORK(&vwork->work, vfio_lock_acct_bg);
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vwork->mm = mm;
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vwork->npage = npage;
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schedule_work(&vwork->work);
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}
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/*
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* Some mappings aren't backed by a struct page, for example an mmap'd
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* MMIO range for our own or another device. These use a different
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* pfn conversion and shouldn't be tracked as locked pages.
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*/
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static bool is_invalid_reserved_pfn(unsigned long pfn)
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{
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if (pfn_valid(pfn)) {
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bool reserved;
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struct page *tail = pfn_to_page(pfn);
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struct page *head = compound_trans_head(tail);
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reserved = !!(PageReserved(head));
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if (head != tail) {
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/*
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* "head" is not a dangling pointer
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* (compound_trans_head takes care of that)
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* but the hugepage may have been split
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* from under us (and we may not hold a
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* reference count on the head page so it can
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* be reused before we run PageReferenced), so
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* we've to check PageTail before returning
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* what we just read.
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*/
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smp_rmb();
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if (PageTail(tail))
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return reserved;
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}
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return PageReserved(tail);
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}
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return true;
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}
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static int put_pfn(unsigned long pfn, int prot)
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{
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if (!is_invalid_reserved_pfn(pfn)) {
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struct page *page = pfn_to_page(pfn);
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if (prot & IOMMU_WRITE)
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SetPageDirty(page);
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put_page(page);
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return 1;
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}
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return 0;
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}
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/* Unmap DMA region */
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static long __vfio_dma_do_unmap(struct vfio_iommu *iommu, dma_addr_t iova,
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long npage, int prot)
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{
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long i, unlocked = 0;
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for (i = 0; i < npage; i++, iova += PAGE_SIZE) {
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unsigned long pfn;
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pfn = iommu_iova_to_phys(iommu->domain, iova) >> PAGE_SHIFT;
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if (pfn) {
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iommu_unmap(iommu->domain, iova, PAGE_SIZE);
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unlocked += put_pfn(pfn, prot);
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}
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}
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return unlocked;
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}
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static void vfio_dma_unmap(struct vfio_iommu *iommu, dma_addr_t iova,
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long npage, int prot)
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{
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long unlocked;
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unlocked = __vfio_dma_do_unmap(iommu, iova, npage, prot);
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vfio_lock_acct(-unlocked);
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}
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static int vaddr_get_pfn(unsigned long vaddr, int prot, unsigned long *pfn)
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{
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struct page *page[1];
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struct vm_area_struct *vma;
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int ret = -EFAULT;
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if (get_user_pages_fast(vaddr, 1, !!(prot & IOMMU_WRITE), page) == 1) {
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*pfn = page_to_pfn(page[0]);
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return 0;
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}
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down_read(¤t->mm->mmap_sem);
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vma = find_vma_intersection(current->mm, vaddr, vaddr + 1);
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if (vma && vma->vm_flags & VM_PFNMAP) {
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*pfn = ((vaddr - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;
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if (is_invalid_reserved_pfn(*pfn))
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ret = 0;
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}
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up_read(¤t->mm->mmap_sem);
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return ret;
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}
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/* Map DMA region */
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static int __vfio_dma_map(struct vfio_iommu *iommu, dma_addr_t iova,
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unsigned long vaddr, long npage, int prot)
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{
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dma_addr_t start = iova;
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long i, locked = 0;
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int ret;
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/* Verify that pages are not already mapped */
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for (i = 0; i < npage; i++, iova += PAGE_SIZE)
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if (iommu_iova_to_phys(iommu->domain, iova))
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return -EBUSY;
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iova = start;
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if (iommu->cache)
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prot |= IOMMU_CACHE;
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/*
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* XXX We break mappings into pages and use get_user_pages_fast to
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* pin the pages in memory. It's been suggested that mlock might
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* provide a more efficient mechanism, but nothing prevents the
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* user from munlocking the pages, which could then allow the user
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* access to random host memory. We also have no guarantee from the
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* IOMMU API that the iommu driver can unmap sub-pages of previous
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* mappings. This means we might lose an entire range if a single
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* page within it is unmapped. Single page mappings are inefficient,
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* but provide the most flexibility for now.
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*/
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for (i = 0; i < npage; i++, iova += PAGE_SIZE, vaddr += PAGE_SIZE) {
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unsigned long pfn = 0;
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ret = vaddr_get_pfn(vaddr, prot, &pfn);
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if (ret) {
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__vfio_dma_do_unmap(iommu, start, i, prot);
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return ret;
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}
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/*
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* Only add actual locked pages to accounting
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* XXX We're effectively marking a page locked for every
|
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* IOVA page even though it's possible the user could be
|
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* backing multiple IOVAs with the same vaddr. This over-
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* penalizes the user process, but we currently have no
|
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* easy way to do this properly.
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|
*/
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if (!is_invalid_reserved_pfn(pfn))
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locked++;
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ret = iommu_map(iommu->domain, iova,
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(phys_addr_t)pfn << PAGE_SHIFT,
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PAGE_SIZE, prot);
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|
if (ret) {
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/* Back out mappings on error */
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put_pfn(pfn, prot);
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__vfio_dma_do_unmap(iommu, start, i, prot);
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return ret;
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|
}
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}
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vfio_lock_acct(locked);
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return 0;
|
||||||
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}
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||||||
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|
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static inline bool ranges_overlap(dma_addr_t start1, size_t size1,
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dma_addr_t start2, size_t size2)
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|
{
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|
if (start1 < start2)
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return (start2 - start1 < size1);
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|
else if (start2 < start1)
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return (start1 - start2 < size2);
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return (size1 > 0 && size2 > 0);
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}
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static struct vfio_dma *vfio_find_dma(struct vfio_iommu *iommu,
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dma_addr_t start, size_t size)
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||||||
|
{
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struct vfio_dma *dma;
|
||||||
|
|
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|
list_for_each_entry(dma, &iommu->dma_list, next) {
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if (ranges_overlap(dma->iova, NPAGE_TO_SIZE(dma->npage),
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start, size))
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return dma;
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}
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return NULL;
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|
}
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static long vfio_remove_dma_overlap(struct vfio_iommu *iommu, dma_addr_t start,
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|
size_t size, struct vfio_dma *dma)
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|
{
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|
struct vfio_dma *split;
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long npage_lo, npage_hi;
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/* Existing dma region is completely covered, unmap all */
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if (start <= dma->iova &&
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start + size >= dma->iova + NPAGE_TO_SIZE(dma->npage)) {
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|
vfio_dma_unmap(iommu, dma->iova, dma->npage, dma->prot);
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list_del(&dma->next);
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npage_lo = dma->npage;
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||||||
|
kfree(dma);
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||||||
|
return npage_lo;
|
||||||
|
}
|
||||||
|
|
||||||
|
/* Overlap low address of existing range */
|
||||||
|
if (start <= dma->iova) {
|
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|
size_t overlap;
|
||||||
|
|
||||||
|
overlap = start + size - dma->iova;
|
||||||
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npage_lo = overlap >> PAGE_SHIFT;
|
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|
|
||||||
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vfio_dma_unmap(iommu, dma->iova, npage_lo, dma->prot);
|
||||||
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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)) {
|
||||||
|
pr_warn("%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)) {
|
||||||
|
pr_warn("%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;
|
||||||
|
}
|
||||||
|
|
||||||
|
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,
|
||||||
|
};
|
||||||
|
|
||||||
|
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);
|
||||||
|
|
@ -98,7 +98,7 @@ extern void vfio_unregister_iommu_driver(
|
||||||
|
|
||||||
/* Extensions */
|
/* Extensions */
|
||||||
|
|
||||||
/* None yet */
|
#define VFIO_TYPE1_IOMMU 1
|
||||||
|
|
||||||
/*
|
/*
|
||||||
* The IOCTL interface is designed for extensibility by embedding the
|
* 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)
|
#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 */
|
#endif /* VFIO_H */
|
||||||
|
|
|
||||||
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