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1// SPDX-License-Identifier: GPL-2.02/*3 * Generic PCI resource mmap helper4 *5 * Copyright © 2017 Amazon.com, Inc. or its affiliates.6 *7 * Author: David Woodhouse <dwmw2@infradead.org>8 */9 10#include <linux/kernel.h>11#include <linux/mm.h>12#include <linux/pci.h>13 14#include "pci.h"15 16#ifdef ARCH_GENERIC_PCI_MMAP_RESOURCE17 18static const struct vm_operations_struct pci_phys_vm_ops = {19#ifdef CONFIG_HAVE_IOREMAP_PROT20 .access = generic_access_phys,21#endif22};23 24int pci_mmap_resource_range(struct pci_dev *pdev, int bar,25 struct vm_area_struct *vma,26 enum pci_mmap_state mmap_state, int write_combine)27{28 unsigned long size;29 int ret;30 31 size = ((pci_resource_len(pdev, bar) - 1) >> PAGE_SHIFT) + 1;32 if (vma->vm_pgoff + vma_pages(vma) > size)33 return -EINVAL;34 35 if (write_combine)36 vma->vm_page_prot = pgprot_writecombine(vma->vm_page_prot);37 else38 vma->vm_page_prot = pgprot_device(vma->vm_page_prot);39 40 if (mmap_state == pci_mmap_io) {41 ret = pci_iobar_pfn(pdev, bar, vma);42 if (ret)43 return ret;44 } else45 vma->vm_pgoff += (pci_resource_start(pdev, bar) >> PAGE_SHIFT);46 47 vma->vm_ops = &pci_phys_vm_ops;48 49 return io_remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,50 vma->vm_end - vma->vm_start,51 vma->vm_page_prot);52}53 54#endif55 56#if (defined(CONFIG_SYSFS) || defined(CONFIG_PROC_FS)) && \57 (defined(HAVE_PCI_MMAP) || defined(ARCH_GENERIC_PCI_MMAP_RESOURCE))58 59int pci_mmap_fits(struct pci_dev *pdev, int resno, struct vm_area_struct *vma,60 enum pci_mmap_api mmap_api)61{62 resource_size_t pci_start = 0, pci_end;63 unsigned long nr, start, size;64 65 if (pci_resource_len(pdev, resno) == 0)66 return 0;67 nr = vma_pages(vma);68 start = vma->vm_pgoff;69 size = ((pci_resource_len(pdev, resno) - 1) >> PAGE_SHIFT) + 1;70 if (mmap_api == PCI_MMAP_PROCFS) {71 pci_resource_to_user(pdev, resno, &pdev->resource[resno],72 &pci_start, &pci_end);73 pci_start >>= PAGE_SHIFT;74 }75 if (start >= pci_start && start < pci_start + size &&76 start + nr <= pci_start + size)77 return 1;78 return 0;79}80 81#endif82