diff options
Diffstat (limited to '')
| -rw-r--r-- | drivers/pci/mmap.c | 52 |
1 files changed, 52 insertions, 0 deletions
diff --git a/drivers/pci/mmap.c b/drivers/pci/mmap.c new file mode 100644 index 000000000..450403905 --- /dev/null +++ b/drivers/pci/mmap.c @@ -0,0 +1,52 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Generic PCI resource mmap helper + * + * Copyright © 2017 Amazon.com, Inc. or its affiliates. + * + * Author: David Woodhouse <dwmw2@infradead.org> + */ + +#include <linux/kernel.h> +#include <linux/mm.h> +#include <linux/pci.h> + +#ifdef ARCH_GENERIC_PCI_MMAP_RESOURCE + +static const struct vm_operations_struct pci_phys_vm_ops = { +#ifdef CONFIG_HAVE_IOREMAP_PROT + .access = generic_access_phys, +#endif +}; + +int pci_mmap_resource_range(struct pci_dev *pdev, int bar, + struct vm_area_struct *vma, + enum pci_mmap_state mmap_state, int write_combine) +{ + unsigned long size; + int ret; + + size = ((pci_resource_len(pdev, bar) - 1) >> PAGE_SHIFT) + 1; + if (vma->vm_pgoff + vma_pages(vma) > size) + return -EINVAL; + + if (write_combine) + vma->vm_page_prot = pgprot_writecombine(vma->vm_page_prot); + else + vma->vm_page_prot = pgprot_device(vma->vm_page_prot); + + if (mmap_state == pci_mmap_io) { + ret = pci_iobar_pfn(pdev, bar, vma); + if (ret) + return ret; + } else + vma->vm_pgoff += (pci_resource_start(pdev, bar) >> PAGE_SHIFT); + + vma->vm_ops = &pci_phys_vm_ops; + + return io_remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff, + vma->vm_end - vma->vm_start, + vma->vm_page_prot); +} + +#endif |