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![Alex Williamson](/assets/img/avatar_default.png)
We also don't handle unpinning zero pages as an error on other exits so we can fix that inconsistency by rolling in the next conditional return. Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
929 lines
22 KiB
C
929 lines
22 KiB
C
/*
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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/rbtree.h>
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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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static bool disable_hugepages;
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module_param_named(disable_hugepages,
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disable_hugepages, bool, S_IRUGO | S_IWUSR);
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MODULE_PARM_DESC(disable_hugepages,
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"Disable VFIO IOMMU support for IOMMU hugepages.");
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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 rb_root 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 rb_node node;
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dma_addr_t iova; /* Device address */
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unsigned long vaddr; /* Process virtual addr */
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size_t size; /* Map size (bytes) */
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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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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 rb_node *node = iommu->dma_list.rb_node;
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while (node) {
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struct vfio_dma *dma = rb_entry(node, struct vfio_dma, node);
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if (start + size <= dma->iova)
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node = node->rb_left;
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else if (start >= dma->iova + dma->size)
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node = node->rb_right;
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else
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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 void vfio_insert_dma(struct vfio_iommu *iommu, struct vfio_dma *new)
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{
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struct rb_node **link = &iommu->dma_list.rb_node, *parent = NULL;
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struct vfio_dma *dma;
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while (*link) {
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parent = *link;
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dma = rb_entry(parent, struct vfio_dma, node);
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if (new->iova + new->size <= dma->iova)
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link = &(*link)->rb_left;
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else
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link = &(*link)->rb_right;
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}
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rb_link_node(&new->node, parent, link);
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rb_insert_color(&new->node, &iommu->dma_list);
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}
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static void vfio_remove_dma(struct vfio_iommu *iommu, struct vfio_dma *old)
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{
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rb_erase(&old->node, &iommu->dma_list);
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}
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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 || !npage)
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return; /* process exited or nothing to do */
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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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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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/*
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* Attempt to pin pages. We really don't want to track all the pfns and
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* the iommu can only map chunks of consecutive pfns anyway, so get the
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* first page and all consecutive pages with the same locking.
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*/
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static long vfio_pin_pages(unsigned long vaddr, long npage,
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int prot, unsigned long *pfn_base)
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{
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unsigned long limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
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bool lock_cap = capable(CAP_IPC_LOCK);
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long ret, i;
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if (!current->mm)
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return -ENODEV;
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ret = vaddr_get_pfn(vaddr, prot, pfn_base);
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if (ret)
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return ret;
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if (is_invalid_reserved_pfn(*pfn_base))
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return 1;
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if (!lock_cap && current->mm->locked_vm + 1 > limit) {
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put_pfn(*pfn_base, prot);
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pr_warn("%s: RLIMIT_MEMLOCK (%ld) exceeded\n", __func__,
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limit << PAGE_SHIFT);
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return -ENOMEM;
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}
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if (unlikely(disable_hugepages)) {
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vfio_lock_acct(1);
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return 1;
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}
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/* Lock all the consecutive pages from pfn_base */
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for (i = 1, vaddr += PAGE_SIZE; i < npage; i++, 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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break;
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if (pfn != *pfn_base + i || is_invalid_reserved_pfn(pfn)) {
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put_pfn(pfn, prot);
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break;
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}
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if (!lock_cap && current->mm->locked_vm + i + 1 > limit) {
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put_pfn(pfn, prot);
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pr_warn("%s: RLIMIT_MEMLOCK (%ld) exceeded\n",
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__func__, limit << PAGE_SHIFT);
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break;
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}
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}
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vfio_lock_acct(i);
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return i;
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}
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static long vfio_unpin_pages(unsigned long pfn, long npage,
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int prot, bool do_accounting)
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{
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unsigned long unlocked = 0;
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long i;
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for (i = 0; i < npage; i++)
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unlocked += put_pfn(pfn++, prot);
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if (do_accounting)
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vfio_lock_acct(-unlocked);
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return unlocked;
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}
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static int vfio_unmap_unpin(struct vfio_iommu *iommu, struct vfio_dma *dma,
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dma_addr_t iova, size_t *size)
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{
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dma_addr_t start = iova, end = iova + *size;
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long unlocked = 0;
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while (iova < end) {
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size_t unmapped;
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phys_addr_t phys;
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/*
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* We use the IOMMU to track the physical address. This
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* saves us from having a lot more entries in our mapping
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* tree. The downside is that we don't track the size
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* used to do the mapping. We request unmap of a single
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* page, but expect IOMMUs that support large pages to
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* unmap a larger chunk.
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*/
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phys = iommu_iova_to_phys(iommu->domain, iova);
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if (WARN_ON(!phys)) {
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iova += PAGE_SIZE;
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continue;
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}
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unmapped = iommu_unmap(iommu->domain, iova, PAGE_SIZE);
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if (!unmapped)
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break;
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unlocked += vfio_unpin_pages(phys >> PAGE_SHIFT,
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unmapped >> PAGE_SHIFT,
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dma->prot, false);
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iova += unmapped;
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}
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vfio_lock_acct(-unlocked);
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*size = iova - start;
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return 0;
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}
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static int 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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size_t offset, overlap, tmp;
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struct vfio_dma *split;
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int ret;
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if (!*size)
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return 0;
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/*
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* Existing dma region is completely covered, unmap all. This is
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* the likely case since userspace tends to map and unmap buffers
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* in one shot rather than multiple mappings within a buffer.
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*/
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if (likely(start <= dma->iova &&
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start + *size >= dma->iova + dma->size)) {
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*size = dma->size;
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ret = vfio_unmap_unpin(iommu, dma, dma->iova, size);
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if (ret)
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return ret;
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/*
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* Did we remove more than we have? Should never happen
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* since a vfio_dma is contiguous in iova and vaddr.
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*/
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WARN_ON(*size != dma->size);
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vfio_remove_dma(iommu, dma);
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kfree(dma);
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return 0;
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}
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/* Overlap low address of existing range */
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if (start <= dma->iova) {
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overlap = start + *size - dma->iova;
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ret = vfio_unmap_unpin(iommu, dma, dma->iova, &overlap);
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if (ret)
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return ret;
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vfio_remove_dma(iommu, dma);
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/*
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* Check, we may have removed to whole vfio_dma. If not
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* fixup and re-insert.
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*/
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if (overlap < dma->size) {
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dma->iova += overlap;
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dma->vaddr += overlap;
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dma->size -= overlap;
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vfio_insert_dma(iommu, dma);
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} else
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kfree(dma);
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*size = overlap;
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return 0;
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}
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/* Overlap high address of existing range */
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if (start + *size >= dma->iova + dma->size) {
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offset = start - dma->iova;
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overlap = dma->size - offset;
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ret = vfio_unmap_unpin(iommu, dma, start, &overlap);
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if (ret)
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return ret;
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dma->size -= overlap;
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*size = overlap;
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return 0;
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}
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/* Split existing */
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/*
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* Allocate our tracking structure early even though it may not
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* be used. An Allocation failure later loses track of pages and
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* is more difficult to unwind.
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*/
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split = kzalloc(sizeof(*split), GFP_KERNEL);
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if (!split)
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return -ENOMEM;
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offset = start - dma->iova;
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ret = vfio_unmap_unpin(iommu, dma, start, size);
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if (ret || !*size) {
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kfree(split);
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return ret;
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}
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tmp = dma->size;
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/* Resize the lower vfio_dma in place, before the below insert */
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dma->size = offset;
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/* Insert new for remainder, assuming it didn't all get unmapped */
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if (likely(offset + *size < tmp)) {
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split->size = tmp - offset - *size;
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split->iova = dma->iova + offset + *size;
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split->vaddr = dma->vaddr + offset + *size;
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split->prot = dma->prot;
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vfio_insert_dma(iommu, split);
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} else
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kfree(split);
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return 0;
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}
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static int vfio_dma_do_unmap(struct vfio_iommu *iommu,
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struct vfio_iommu_type1_dma_unmap *unmap)
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{
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uint64_t mask;
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struct vfio_dma *dma;
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size_t unmapped = 0, size;
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int ret = 0;
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mask = ((uint64_t)1 << __ffs(iommu->domain->ops->pgsize_bitmap)) - 1;
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if (unmap->iova & mask)
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return -EINVAL;
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if (!unmap->size || unmap->size & mask)
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return -EINVAL;
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WARN_ON(mask & PAGE_MASK);
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mutex_lock(&iommu->lock);
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while ((dma = vfio_find_dma(iommu, unmap->iova, unmap->size))) {
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size = unmap->size;
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ret = vfio_remove_dma_overlap(iommu, unmap->iova, &size, dma);
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if (ret || !size)
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break;
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unmapped += size;
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}
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mutex_unlock(&iommu->lock);
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/*
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* We may unmap more than requested, update the unmap struct so
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* userspace can know.
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*/
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unmap->size = unmapped;
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return ret;
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}
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|
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/*
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* Turns out AMD IOMMU has a page table bug where it won't map large pages
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* to a region that previously mapped smaller pages. This should be fixed
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* soon, so this is just a temporary workaround to break mappings down into
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* PAGE_SIZE. Better to map smaller pages than nothing.
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*/
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static int map_try_harder(struct vfio_iommu *iommu, dma_addr_t iova,
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unsigned long pfn, long npage, int prot)
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{
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|
long i;
|
|
int ret;
|
|
|
|
for (i = 0; i < npage; i++, pfn++, iova += PAGE_SIZE) {
|
|
ret = iommu_map(iommu->domain, iova,
|
|
(phys_addr_t)pfn << PAGE_SHIFT,
|
|
PAGE_SIZE, prot);
|
|
if (ret)
|
|
break;
|
|
}
|
|
|
|
for (; i < npage && i > 0; i--, iova -= PAGE_SIZE)
|
|
iommu_unmap(iommu->domain, iova, PAGE_SIZE);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int vfio_dma_do_map(struct vfio_iommu *iommu,
|
|
struct vfio_iommu_type1_dma_map *map)
|
|
{
|
|
dma_addr_t end, iova;
|
|
unsigned long vaddr = map->vaddr;
|
|
size_t size = map->size;
|
|
long npage;
|
|
int ret = 0, prot = 0;
|
|
uint64_t mask;
|
|
|
|
end = map->iova + map->size;
|
|
|
|
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 (iommu->cache)
|
|
prot |= IOMMU_CACHE;
|
|
|
|
if (vaddr & mask)
|
|
return -EINVAL;
|
|
if (map->iova & mask)
|
|
return -EINVAL;
|
|
if (!map->size || map->size & mask)
|
|
return -EINVAL;
|
|
|
|
WARN_ON(mask & PAGE_MASK);
|
|
|
|
/* Don't allow IOVA wrap */
|
|
if (end && end < map->iova)
|
|
return -EINVAL;
|
|
|
|
/* Don't allow virtual address wrap */
|
|
if (vaddr + map->size && vaddr + map->size < vaddr)
|
|
return -EINVAL;
|
|
|
|
mutex_lock(&iommu->lock);
|
|
|
|
if (vfio_find_dma(iommu, map->iova, map->size)) {
|
|
mutex_unlock(&iommu->lock);
|
|
return -EEXIST;
|
|
}
|
|
|
|
for (iova = map->iova; iova < end; iova += size, vaddr += size) {
|
|
struct vfio_dma *dma = NULL;
|
|
unsigned long pfn;
|
|
long i;
|
|
|
|
/* Pin a contiguous chunk of memory */
|
|
npage = vfio_pin_pages(vaddr, (end - iova) >> PAGE_SHIFT,
|
|
prot, &pfn);
|
|
if (npage <= 0) {
|
|
WARN_ON(!npage);
|
|
ret = (int)npage;
|
|
break;
|
|
}
|
|
|
|
/* Verify pages are not already mapped */
|
|
for (i = 0; i < npage; i++) {
|
|
if (iommu_iova_to_phys(iommu->domain,
|
|
iova + (i << PAGE_SHIFT))) {
|
|
vfio_unpin_pages(pfn, npage, prot, true);
|
|
ret = -EBUSY;
|
|
break;
|
|
}
|
|
}
|
|
|
|
ret = iommu_map(iommu->domain, iova,
|
|
(phys_addr_t)pfn << PAGE_SHIFT,
|
|
npage << PAGE_SHIFT, prot);
|
|
if (ret) {
|
|
if (ret != -EBUSY ||
|
|
map_try_harder(iommu, iova, pfn, npage, prot)) {
|
|
vfio_unpin_pages(pfn, npage, prot, true);
|
|
break;
|
|
}
|
|
}
|
|
|
|
size = npage << PAGE_SHIFT;
|
|
|
|
/*
|
|
* Check if we abut a region below - nothing below 0.
|
|
* This is the most likely case when mapping chunks of
|
|
* physically contiguous regions within a virtual address
|
|
* range. Update the abutting entry in place since iova
|
|
* doesn't change.
|
|
*/
|
|
if (likely(iova)) {
|
|
struct vfio_dma *tmp;
|
|
tmp = vfio_find_dma(iommu, iova - 1, 1);
|
|
if (tmp && tmp->prot == prot &&
|
|
tmp->vaddr + tmp->size == vaddr) {
|
|
tmp->size += size;
|
|
iova = tmp->iova;
|
|
size = tmp->size;
|
|
vaddr = tmp->vaddr;
|
|
dma = tmp;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Check if we abut a region above - nothing above ~0 + 1.
|
|
* If we abut above and below, remove and free. If only
|
|
* abut above, remove, modify, reinsert.
|
|
*/
|
|
if (likely(iova + size)) {
|
|
struct vfio_dma *tmp;
|
|
tmp = vfio_find_dma(iommu, iova + size, 1);
|
|
if (tmp && tmp->prot == prot &&
|
|
tmp->vaddr == vaddr + size) {
|
|
vfio_remove_dma(iommu, tmp);
|
|
if (dma) {
|
|
dma->size += tmp->size;
|
|
kfree(tmp);
|
|
} else {
|
|
size += tmp->size;
|
|
tmp->size = size;
|
|
tmp->iova = iova;
|
|
tmp->vaddr = vaddr;
|
|
vfio_insert_dma(iommu, tmp);
|
|
dma = tmp;
|
|
}
|
|
}
|
|
}
|
|
|
|
if (!dma) {
|
|
dma = kzalloc(sizeof(*dma), GFP_KERNEL);
|
|
if (!dma) {
|
|
iommu_unmap(iommu->domain, iova, size);
|
|
vfio_unpin_pages(pfn, npage, prot, true);
|
|
ret = -ENOMEM;
|
|
break;
|
|
}
|
|
|
|
dma->size = size;
|
|
dma->iova = iova;
|
|
dma->vaddr = vaddr;
|
|
dma->prot = prot;
|
|
vfio_insert_dma(iommu, dma);
|
|
}
|
|
}
|
|
|
|
if (ret) {
|
|
struct vfio_dma *tmp;
|
|
iova = map->iova;
|
|
size = map->size;
|
|
while ((tmp = vfio_find_dma(iommu, iova, size))) {
|
|
int r = vfio_remove_dma_overlap(iommu, iova,
|
|
&size, tmp);
|
|
if (WARN_ON(r || !size))
|
|
break;
|
|
}
|
|
}
|
|
|
|
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);
|
|
iommu->dma_list = RB_ROOT;
|
|
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 rb_node *node;
|
|
|
|
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);
|
|
}
|
|
|
|
while ((node = rb_first(&iommu->dma_list))) {
|
|
struct vfio_dma *dma = rb_entry(node, struct vfio_dma, node);
|
|
size_t size = dma->size;
|
|
vfio_remove_dma_overlap(iommu, dma->iova, &size, dma);
|
|
if (WARN_ON(!size))
|
|
break;
|
|
}
|
|
|
|
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;
|
|
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);
|
|
}
|
|
|
|
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);
|