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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
commit | 5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch) | |
tree | a94efe259b9009378be6d90eb30d2b019d95c194 /drivers/pci/mmap.c | |
parent | Initial commit. (diff) | |
download | linux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.tar.xz linux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.zip |
Adding upstream version 5.10.209.upstream/5.10.209
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/pci/mmap.c')
-rw-r--r-- | drivers/pci/mmap.c | 96 |
1 files changed, 96 insertions, 0 deletions
diff --git a/drivers/pci/mmap.c b/drivers/pci/mmap.c new file mode 100644 index 000000000..b8c901198 --- /dev/null +++ b/drivers/pci/mmap.c @@ -0,0 +1,96 @@ +// 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: Implement 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 |