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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
commit5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch)
treea94efe259b9009378be6d90eb30d2b019d95c194 /drivers/pci/mmap.c
parentInitial commit. (diff)
downloadlinux-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.c96
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