diff mbox series

[RFC,21/21] pci: Define pci_iomap_range_encrypted

Message ID 20240823132137.336874-22-aik@amd.com (mailing list archive)
State New, archived
Headers show
Series Secure VFIO, TDISP, SEV TIO | expand

Commit Message

Alexey Kardashevskiy Aug. 23, 2024, 1:21 p.m. UTC 
So far PCI BARs could not be mapped as encrypted so there was no
need in API supporting encrypted mappings. TDISP is adding such
support so add pci_iomap_range_encrypted() to allow PCI drivers
do the encrypted mapping when needed.

Signed-off-by: Alexey Kardashevskiy <aik@amd.com>
---
 include/asm-generic/pci_iomap.h |  4 ++++
 drivers/pci/iomap.c             | 24 ++++++++++++++++++++
 2 files changed, 28 insertions(+)
diff mbox series

Patch

diff --git a/include/asm-generic/pci_iomap.h b/include/asm-generic/pci_iomap.h
index 8fbb0a55545d..d7b922c5ab86 100644
--- a/include/asm-generic/pci_iomap.h
+++ b/include/asm-generic/pci_iomap.h
@@ -15,6 +15,10 @@  extern void __iomem *pci_iomap_wc(struct pci_dev *dev, int bar, unsigned long ma
 extern void __iomem *pci_iomap_range(struct pci_dev *dev, int bar,
 				     unsigned long offset,
 				     unsigned long maxlen);
+extern void __iomem *pci_iomap_range_encrypted(struct pci_dev *dev,
+					       int bar,
+					       unsigned long offset,
+					       unsigned long maxlen);
 extern void __iomem *pci_iomap_wc_range(struct pci_dev *dev, int bar,
 					unsigned long offset,
 					unsigned long maxlen);
diff --git a/drivers/pci/iomap.c b/drivers/pci/iomap.c
index a715a4803c95..2bf8ef4f672b 100644
--- a/drivers/pci/iomap.c
+++ b/drivers/pci/iomap.c
@@ -52,6 +52,30 @@  void __iomem *pci_iomap_range(struct pci_dev *dev,
 }
 EXPORT_SYMBOL(pci_iomap_range);
 
+void __iomem *pci_iomap_range_encrypted(struct pci_dev *dev,
+					int bar,
+					unsigned long offset,
+					unsigned long maxlen)
+{
+	resource_size_t start = pci_resource_start(dev, bar);
+	resource_size_t len = pci_resource_len(dev, bar);
+	unsigned long flags = pci_resource_flags(dev, bar);
+
+	if (len <= offset || !start)
+		return NULL;
+	len -= offset;
+	start += offset;
+	if (maxlen && len > maxlen)
+		len = maxlen;
+	if (flags & IORESOURCE_IO)
+		return NULL;
+	if (flags & IORESOURCE_MEM)
+		return ioremap_encrypted(start, len);
+	/* What? */
+	return NULL;
+}
+EXPORT_SYMBOL(pci_iomap_range_encrypted);
+
 /**
  * pci_iomap_wc_range - create a virtual WC mapping cookie for a PCI BAR
  * @dev: PCI device that owns the BAR