linux/drivers/pci/mmap.c
Lukas Wunner be9c3a4c8b PCI/sysfs: Compile pci-sysfs.c only if CONFIG_SYSFS=y
It is possible to enable CONFIG_PCI but disable CONFIG_SYSFS and for
space-constrained devices such as routers, such a configuration may
actually make sense.

However pci-sysfs.c is compiled even if CONFIG_SYSFS is disabled,
unnecessarily increasing the kernel's size.

To rectify that:

* Move pci_mmap_fits() to mmap.c.  It is not only needed by
  pci-sysfs.c, but also proc.c.

* Move pci_dev_type to probe.c and make it private.  It references
  pci_dev_attr_groups in pci-sysfs.c.  Make that public instead for
  consistency with pci_dev_groups, pcibus_groups and pci_bus_groups,
  which are likewise public and referenced by struct definitions in
  pci-driver.c and probe.c.

* Define pci_dev_groups, pci_dev_attr_groups, pcibus_groups and
  pci_bus_groups to NULL if CONFIG_SYSFS is disabled.  Provide empty
  static inlines for pci_{create,remove}_legacy_files() and
  pci_{create,remove}_sysfs_dev_files().

Result:

vmlinux size is reduced by 122996 bytes in my arm 32-bit test build.

Link: https://lore.kernel.org/r/85ca95ae8e4d57ccf082c5c069b8b21eb141846e.1698668982.git.lukas@wunner.de
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
2024-03-05 16:08:43 -06:00

82 lines
2.0 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>
#include "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
#if (defined(CONFIG_SYSFS) || defined(CONFIG_PROC_FS)) && \
(defined(HAVE_PCI_MMAP) || defined(ARCH_GENERIC_PCI_MMAP_RESOURCE))
int pci_mmap_fits(struct pci_dev *pdev, int resno, struct vm_area_struct *vma,
enum pci_mmap_api mmap_api)
{
resource_size_t pci_start = 0, pci_end;
unsigned long nr, start, size;
if (pci_resource_len(pdev, resno) == 0)
return 0;
nr = vma_pages(vma);
start = vma->vm_pgoff;
size = ((pci_resource_len(pdev, resno) - 1) >> PAGE_SHIFT) + 1;
if (mmap_api == PCI_MMAP_PROCFS) {
pci_resource_to_user(pdev, resno, &pdev->resource[resno],
&pci_start, &pci_end);
pci_start >>= PAGE_SHIFT;
}
if (start >= pci_start && start < pci_start + size &&
start + nr <= pci_start + size)
return 1;
return 0;
}
#endif