From f719582435afe9c7985206e42d804ea6aa315d33 Mon Sep 17 00:00:00 2001 From: David Woodhouse Date: Wed, 12 Apr 2017 13:25:59 +0100 Subject: PCI: Add pci_mmap_resource_range() and use it for ARM64 Starting to leave behind the legacy of the pci_mmap_page_range() interface which takes "user-visible" BAR addresses. This takes just the resource and offset. For now, both APIs coexist and depending on the platform, one is implemented as a wrapper around the other. Signed-off-by: David Woodhouse Signed-off-by: Bjorn Helgaas --- drivers/pci/Makefile | 2 +- drivers/pci/mmap.c | 95 +++++++++++++++++++++++++++++++++++++++++++++++++ drivers/pci/pci-sysfs.c | 13 ++----- drivers/pci/pci.h | 4 +-- 4 files changed, 101 insertions(+), 13 deletions(-) create mode 100644 drivers/pci/mmap.c (limited to 'drivers/pci') diff --git a/drivers/pci/Makefile b/drivers/pci/Makefile index 8db5079..3d40e41 100644 --- a/drivers/pci/Makefile +++ b/drivers/pci/Makefile @@ -4,7 +4,7 @@ obj-y += access.o bus.o probe.o host-bridge.o remove.o pci.o \ pci-driver.o search.o pci-sysfs.o rom.o setup-res.o \ - irq.o vpd.o setup-bus.o vc.o + irq.o vpd.o setup-bus.o vc.o mmap.o obj-$(CONFIG_PROC_FS) += proc.o obj-$(CONFIG_SYSFS) += slot.o diff --git a/drivers/pci/mmap.c b/drivers/pci/mmap.c new file mode 100644 index 0000000..b7aca9c --- /dev/null +++ b/drivers/pci/mmap.c @@ -0,0 +1,95 @@ +/* + * mmap.c — generic PCI resource mmap helper + * + * Copyright © 2017 Amazon.com, Inc. or its affiliates. + * + * Author: David Woodhouse + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include +#include +#include + +#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; + + if (mmap_state == pci_mmap_io) + return -EINVAL; + + 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); + + 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 diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c index bfd9efe..10feb98 100644 --- a/drivers/pci/pci-sysfs.c +++ b/drivers/pci/pci-sysfs.c @@ -980,7 +980,7 @@ void pci_remove_legacy_files(struct pci_bus *b) } #endif /* HAVE_PCI_LEGACY */ -#ifdef HAVE_PCI_MMAP +#if 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) @@ -1019,7 +1019,6 @@ static int pci_mmap_resource(struct kobject *kobj, struct bin_attribute *attr, struct pci_dev *pdev = to_pci_dev(kobj_to_dev(kobj)); int bar = (unsigned long)attr->private; enum pci_mmap_state mmap_type; - resource_size_t start, end; struct resource *res = &pdev->resource[bar]; if (res->flags & IORESOURCE_MEM && iomem_is_exclusive(res->start)) @@ -1033,15 +1032,9 @@ static int pci_mmap_resource(struct kobject *kobj, struct bin_attribute *attr, (u64)pci_resource_len(pdev, bar)); return -EINVAL; } - - /* 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, res, &start, &end); - vma->vm_pgoff += start >> PAGE_SHIFT; mmap_type = res->flags & IORESOURCE_MEM ? pci_mmap_mem : pci_mmap_io; - return pci_mmap_page_range(pdev, bar, vma, mmap_type, write_combine); + + return pci_mmap_resource_range(pdev, bar, vma, mmap_type, write_combine); } static int pci_mmap_resource_uc(struct file *filp, struct kobject *kobj, diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h index 8dd38e6..8e5ca2d 100644 --- a/drivers/pci/pci.h +++ b/drivers/pci/pci.h @@ -21,14 +21,14 @@ void pci_create_firmware_label_files(struct pci_dev *pdev); void pci_remove_firmware_label_files(struct pci_dev *pdev); #endif void pci_cleanup_rom(struct pci_dev *dev); -#ifdef HAVE_PCI_MMAP + enum pci_mmap_api { PCI_MMAP_SYSFS, /* mmap on /sys/bus/pci/devices//resource */ PCI_MMAP_PROCFS /* mmap on /proc/bus/pci/ */ }; int pci_mmap_fits(struct pci_dev *pdev, int resno, struct vm_area_struct *vmai, enum pci_mmap_api mmap_api); -#endif + int pci_probe_reset_function(struct pci_dev *dev); /** -- cgit v1.1