82 lines
2.0 KiB
C
82 lines
2.0 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/*
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* Generic PCI resource mmap helper
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*
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* Copyright © 2017 Amazon.com, Inc. or its affiliates.
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*
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* Author: David Woodhouse <dwmw2@infradead.org>
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*/
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#include <linux/kernel.h>
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#include <linux/mm.h>
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#include <linux/pci.h>
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#include "pci.h"
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#ifdef ARCH_GENERIC_PCI_MMAP_RESOURCE
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static const struct vm_operations_struct pci_phys_vm_ops = {
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#ifdef CONFIG_HAVE_IOREMAP_PROT
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.access = generic_access_phys,
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#endif
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};
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int pci_mmap_resource_range(struct pci_dev *pdev, int bar,
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struct vm_area_struct *vma,
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enum pci_mmap_state mmap_state, int write_combine)
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{
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unsigned long size;
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int ret;
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size = ((pci_resource_len(pdev, bar) - 1) >> PAGE_SHIFT) + 1;
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if (vma->vm_pgoff + vma_pages(vma) > size)
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return -EINVAL;
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if (write_combine)
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vma->vm_page_prot = pgprot_writecombine(vma->vm_page_prot);
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else
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vma->vm_page_prot = pgprot_device(vma->vm_page_prot);
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if (mmap_state == pci_mmap_io) {
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ret = pci_iobar_pfn(pdev, bar, vma);
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if (ret)
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return ret;
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} else
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vma->vm_pgoff += (pci_resource_start(pdev, bar) >> PAGE_SHIFT);
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vma->vm_ops = &pci_phys_vm_ops;
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return io_remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
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vma->vm_end - vma->vm_start,
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vma->vm_page_prot);
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}
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#endif
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#if (defined(CONFIG_SYSFS) || defined(CONFIG_PROC_FS)) && \
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(defined(HAVE_PCI_MMAP) || defined(ARCH_GENERIC_PCI_MMAP_RESOURCE))
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int pci_mmap_fits(struct pci_dev *pdev, int resno, struct vm_area_struct *vma,
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enum pci_mmap_api mmap_api)
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{
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resource_size_t pci_start = 0, pci_end;
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unsigned long nr, start, size;
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if (pci_resource_len(pdev, resno) == 0)
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return 0;
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nr = vma_pages(vma);
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start = vma->vm_pgoff;
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size = ((pci_resource_len(pdev, resno) - 1) >> PAGE_SHIFT) + 1;
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if (mmap_api == PCI_MMAP_PROCFS) {
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pci_resource_to_user(pdev, resno, &pdev->resource[resno],
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&pci_start, &pci_end);
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pci_start >>= PAGE_SHIFT;
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}
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if (start >= pci_start && start < pci_start + size &&
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start + nr <= pci_start + size)
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return 1;
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return 0;
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}
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#endif
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