df62ab5e0f
Remove pointless comments that tell us the file name, remove blank line comments, follow multi-line comment conventions. No functional change intended. Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
97 lines
2.6 KiB
C
97 lines
2.6 KiB
C
// 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
|
|
|
|
/*
|
|
* Modern setup: generic pci_mmap_resource_range(), and implement the legacy
|
|
* pci_mmap_page_range() (if needed) as a wrapper round it.
|
|
*/
|
|
|
|
#ifdef HAVE_PCI_MMAP
|
|
int pci_mmap_page_range(struct pci_dev *pdev, int bar,
|
|
struct vm_area_struct *vma,
|
|
enum pci_mmap_state mmap_state, int write_combine)
|
|
{
|
|
resource_size_t start, end;
|
|
|
|
pci_resource_to_user(pdev, bar, &pdev->resource[bar], &start, &end);
|
|
|
|
/* Adjust vm_pgoff to be the offset within the resource */
|
|
vma->vm_pgoff -= start >> PAGE_SHIFT;
|
|
return pci_mmap_resource_range(pdev, bar, vma, mmap_state,
|
|
write_combine);
|
|
}
|
|
#endif
|
|
|
|
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);
|
|
}
|
|
|
|
#elif defined(HAVE_PCI_MMAP) /* && !ARCH_GENERIC_PCI_MMAP_RESOURCE */
|
|
|
|
/*
|
|
* Legacy setup: Impement pci_mmap_resource_range() as a wrapper around
|
|
* the architecture's pci_mmap_page_range(), converting to "user visible"
|
|
* addresses as necessary.
|
|
*/
|
|
|
|
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)
|
|
{
|
|
resource_size_t start, end;
|
|
|
|
/*
|
|
* pci_mmap_page_range() expects the same kind of entry as coming
|
|
* from /proc/bus/pci/ which is a "user visible" value. If this is
|
|
* different from the resource itself, arch will do necessary fixup.
|
|
*/
|
|
pci_resource_to_user(pdev, bar, &pdev->resource[bar], &start, &end);
|
|
vma->vm_pgoff += start >> PAGE_SHIFT;
|
|
return pci_mmap_page_range(pdev, bar, vma, mmap_state, write_combine);
|
|
}
|
|
#endif
|