[PATCH v4 11/15] pci: Add pci_iomap_shared{,_range}
From: Kuppuswamy Sathyanarayanan
<sathyanarayanan.kuppuswamy@linux.intel.com>
Date: 2021-08-05 00:54:18
Also in:
linux-alpha, linux-arch, linux-mips, linux-pci, lkml, sparclinux
Subsystem:
generic include/asm header files, library code, pci subsystem, the rest · Maintainers:
Arnd Bergmann, Andrew Morton, Bjorn Helgaas, Linus Torvalds
From: Andi Kleen <redacted> Add a new variant of pci_iomap for mapping all PCI resources of a devices as shared memory with a hypervisor in a confidential guest. Signed-off-by: Andi Kleen <redacted> Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com> --- include/asm-generic/pci_iomap.h | 6 +++++ lib/pci_iomap.c | 46 +++++++++++++++++++++++++++++++++ 2 files changed, 52 insertions(+)
diff --git a/include/asm-generic/pci_iomap.h b/include/asm-generic/pci_iomap.h
index d4f16dcc2ed7..0178ddd7ad88 100644
--- a/include/asm-generic/pci_iomap.h
+++ b/include/asm-generic/pci_iomap.h@@ -18,6 +18,12 @@ extern void __iomem *pci_iomap_range(struct pci_dev *dev, int bar, extern void __iomem *pci_iomap_wc_range(struct pci_dev *dev, int bar, unsigned long offset, unsigned long maxlen); +extern void __iomem *pci_iomap_shared(struct pci_dev *dev, int bar, + unsigned long max); +extern void __iomem *pci_iomap_shared_range(struct pci_dev *dev, int bar, + unsigned long offset, + unsigned long maxlen); + /* Create a virtual mapping cookie for a port on a given PCI device. * Do not call this directly, it exists to make it easier for architectures * to override */
diff --git a/lib/pci_iomap.c b/lib/pci_iomap.c
index 6251c3f651c6..b04e8689eab3 100644
--- a/lib/pci_iomap.c
+++ b/lib/pci_iomap.c@@ -25,6 +25,11 @@ static void __iomem *map_ioremap_wc(phys_addr_t addr, size_t size) return ioremap_wc(addr, size); } +static void __iomem *map_ioremap_shared(phys_addr_t addr, size_t size) +{ + return ioremap_shared(addr, size); +} + static void __iomem *pci_iomap_range_map(struct pci_dev *dev, int bar, unsigned long offset,
@@ -101,6 +106,47 @@ void __iomem *pci_iomap_wc_range(struct pci_dev *dev, } EXPORT_SYMBOL_GPL(pci_iomap_wc_range); +/** + * pci_iomap_shared_range - create a virtual shared mapping cookie for a + * PCI BAR + * @dev: PCI device that owns the BAR + * @bar: BAR number + * @offset: map memory at the given offset in BAR + * @maxlen: max length of the memory to map + * + * Remap a pci device's resources shared in a confidential guest. + * For more details see pci_iomap_range's documentation. + * + * @maxlen specifies the maximum length to map. To get access to + * the complete BAR from offset to the end, pass %0 here. + */ +void __iomem *pci_iomap_shared_range(struct pci_dev *dev, int bar, + unsigned long offset, unsigned long maxlen) +{ + return pci_iomap_range_map(dev, bar, offset, maxlen, + map_ioremap_shared); +} +EXPORT_SYMBOL_GPL(pci_iomap_shared_range); + +/** + * pci_iomap_shared - create a virtual shared mapping cookie for a PCI BAR + * @dev: PCI device that owns the BAR + * @bar: BAR number + * @maxlen: length of the memory to map + * + * See pci_iomap for details. This function creates a shared mapping + * with the host for confidential hosts. + * + * @maxlen specifies the maximum length to map. To get access to the + * complete BAR without checking for its length first, pass %0 here. + */ +void __iomem *pci_iomap_shared(struct pci_dev *dev, int bar, + unsigned long maxlen) +{ + return pci_iomap_shared_range(dev, bar, 0, maxlen); +} +EXPORT_SYMBOL_GPL(pci_iomap_shared); + /** * pci_iomap - create a virtual mapping cookie for a PCI BAR * @dev: PCI device that owns the BAR
--
2.25.1