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Jean-Philippe Brucker

2021-Apr-23 11:38 UTC

[PATCH v2 0/6] Add support for ACPI VIOT

Add a driver for the ACPI VIOT table, which provides topology
information for para-virtual platforms. Enable virtio-iommu on
non-devicetree platforms, including x86.

Since v1 [1]:
* The VIOT header definitions have been picked for v5.13
* Share more code with IORT. Patches 1 and 2 extract the common code
  from IORT.
* Simplify the VIOT driver. Use the existing fwnode infrastructure
  instead of adding hooks to the IOMMU driver.

You can find a QEMU implementation at [2], with extra support for
testing all VIOT nodes including MMIO-based endpoints and IOMMU. This
series, based on linux-next, is at [3]

[1] https://lore.kernel.org/linux-iommu/20210316191652.3401335-1-jean-philippe
at linaro.org/
[2] https://jpbrucker.net/git/qemu/log/?h=virtio-iommu/acpi
[3] https://jpbrucker.net/git/linux/log/?h=virtio-iommu/acpi

Jean-Philippe Brucker (6):
  ACPI: arm64: Move DMA setup operations out of IORT
  ACPI: Move IOMMU setup code out of IORT
  ACPI: Add driver for the VIOT table
  iommu/dma: Pass address limit rather than size to
    iommu_setup_dma_ops()
  iommu/dma: Simplify calls to iommu_setup_dma_ops()
  iommu/virtio: Enable x86 support

 drivers/acpi/Kconfig         |   3 +
 drivers/iommu/Kconfig        |   4 +-
 drivers/acpi/Makefile        |   2 +
 drivers/acpi/arm64/Makefile  |   1 +
 include/acpi/acpi_bus.h      |   3 +
 include/linux/acpi.h         |   3 +
 include/linux/acpi_iort.h    |  14 +-
 include/linux/acpi_viot.h    |  19 ++
 include/linux/dma-iommu.h    |   4 +-
 arch/arm64/mm/dma-mapping.c  |   2 +-
 drivers/acpi/arm64/dma.c     |  50 +++++
 drivers/acpi/arm64/iort.c    | 129 ++-----------
 drivers/acpi/bus.c           |   2 +
 drivers/acpi/scan.c          |  60 +++++-
 drivers/acpi/viot.c          | 350 +++++++++++++++++++++++++++++++++++
 drivers/iommu/amd/iommu.c    |   9 +-
 drivers/iommu/dma-iommu.c    |  17 +-
 drivers/iommu/intel/iommu.c  |  10 +-
 drivers/iommu/virtio-iommu.c |   8 +
 MAINTAINERS                  |   8 +
 20 files changed, 548 insertions(+), 150 deletions(-)
 create mode 100644 include/linux/acpi_viot.h
 create mode 100644 drivers/acpi/arm64/dma.c
 create mode 100644 drivers/acpi/viot.c

-- 
2.31.1

Jean-Philippe Brucker

2021-Apr-23 11:38 UTC

head link

[PATCH v2 1/6] ACPI: arm64: Move DMA setup operations out of IORT

Extract generic DMA setup code out of IORT, so it can be reused by VIOT.
Keep it in drivers/acpi/arm64 for now, since it could break x86
platforms that haven't run this code so far, if they have invalid
tables.

Signed-off-by: Jean-Philippe Brucker <jean-philippe at linaro.org>
---
 drivers/acpi/arm64/Makefile |  1 +
 include/linux/acpi.h        |  3 +++
 include/linux/acpi_iort.h   |  6 ++---
 drivers/acpi/arm64/dma.c    | 50 ++++++++++++++++++++++++++++++++++
 drivers/acpi/arm64/iort.c   | 54 ++++++-------------------------------
 drivers/acpi/scan.c         |  2 +-
 6 files changed, 66 insertions(+), 50 deletions(-)
 create mode 100644 drivers/acpi/arm64/dma.c

diff --git a/drivers/acpi/arm64/Makefile b/drivers/acpi/arm64/Makefile
index 6ff50f4ed947..66acbe77f46e 100644
--- a/drivers/acpi/arm64/Makefile
+++ b/drivers/acpi/arm64/Makefile
@@ -1,3 +1,4 @@
 # SPDX-License-Identifier: GPL-2.0-only
 obj-$(CONFIG_ACPI_IORT) 	+= iort.o
 obj-$(CONFIG_ACPI_GTDT) 	+= gtdt.o
+obj-y				+= dma.o
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index c60745f657e9..7aaa9559cc19 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -259,9 +259,12 @@ void acpi_numa_x2apic_affinity_init(struct
acpi_srat_x2apic_cpu_affinity *pa);
 
 #ifdef CONFIG_ARM64
 void acpi_numa_gicc_affinity_init(struct acpi_srat_gicc_affinity *pa);
+void acpi_arch_dma_setup(struct device *dev, u64 *dma_addr, u64 *dma_size);
 #else
 static inline void
 acpi_numa_gicc_affinity_init(struct acpi_srat_gicc_affinity *pa) { }
+static inline void
+acpi_arch_dma_setup(struct device *dev, u64 *dma_addr, u64 *dma_size) { }
 #endif
 
 int acpi_numa_memory_affinity_init (struct acpi_srat_mem_affinity *ma);
diff --git a/include/linux/acpi_iort.h b/include/linux/acpi_iort.h
index 1a12baa58e40..f7f054833afd 100644
--- a/include/linux/acpi_iort.h
+++ b/include/linux/acpi_iort.h
@@ -34,7 +34,7 @@ struct irq_domain *iort_get_device_domain(struct device *dev,
u32 id,
 void acpi_configure_pmsi_domain(struct device *dev);
 int iort_pmsi_get_dev_id(struct device *dev, u32 *dev_id);
 /* IOMMU interface */
-void iort_dma_setup(struct device *dev, u64 *dma_addr, u64 *size);
+int iort_dma_get_ranges(struct device *dev, u64 *size);
 const struct iommu_ops *iort_iommu_configure_id(struct device *dev,
 						const u32 *id_in);
 int iort_iommu_msi_get_resv_regions(struct device *dev, struct list_head
*head);
@@ -48,8 +48,8 @@ static inline struct irq_domain *iort_get_device_domain(
 { return NULL; }
 static inline void acpi_configure_pmsi_domain(struct device *dev) { }
 /* IOMMU interface */
-static inline void iort_dma_setup(struct device *dev, u64 *dma_addr,
-				  u64 *size) { }
+static inline int iort_dma_get_ranges(struct device *dev, u64 *size)
+{ return -ENODEV; }
 static inline const struct iommu_ops *iort_iommu_configure_id(
 				      struct device *dev, const u32 *id_in)
 { return NULL; }
diff --git a/drivers/acpi/arm64/dma.c b/drivers/acpi/arm64/dma.c
new file mode 100644
index 000000000000..f16739ad3cc0
--- /dev/null
+++ b/drivers/acpi/arm64/dma.c
@@ -0,0 +1,50 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#include <linux/acpi.h>
+#include <linux/acpi_iort.h>
+#include <linux/device.h>
+#include <linux/dma-direct.h>
+
+void acpi_arch_dma_setup(struct device *dev, u64 *dma_addr, u64 *dma_size)
+{
+	int ret;
+	u64 end, mask;
+	u64 dmaaddr = 0, size = 0, offset = 0;
+
+	/*
+	 * If @dev is expected to be DMA-capable then the bus code that created
+	 * it should have initialised its dma_mask pointer by this point. For
+	 * now, we'll continue the legacy behaviour of coercing it to the
+	 * coherent mask if not, but we'll no longer do so quietly.
+	 */
+	if (!dev->dma_mask) {
+		dev_warn(dev, "DMA mask not set\n");
+		dev->dma_mask = &dev->coherent_dma_mask;
+	}
+
+	if (dev->coherent_dma_mask)
+		size = max(dev->coherent_dma_mask, dev->coherent_dma_mask + 1);
+	else
+		size = 1ULL << 32;
+
+	ret = acpi_dma_get_range(dev, &dmaaddr, &offset, &size);
+	if (ret == -ENODEV)
+		ret = iort_dma_get_ranges(dev, &size);
+	if (!ret) {
+		/*
+		 * Limit coherent and dma mask based on size retrieved from
+		 * firmware.
+		 */
+		end = dmaaddr + size - 1;
+		mask = DMA_BIT_MASK(ilog2(end) + 1);
+		dev->bus_dma_limit = end;
+		dev->coherent_dma_mask = min(dev->coherent_dma_mask, mask);
+		*dev->dma_mask = min(*dev->dma_mask, mask);
+	}
+
+	*dma_addr = dmaaddr;
+	*dma_size = size;
+
+	ret = dma_direct_set_offset(dev, dmaaddr + offset, dmaaddr, size);
+
+	dev_dbg(dev, "dma_offset(%#08llx)%s\n", offset, ret ? "
failed!" : "");
+}
diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c
index 3912a1f6058e..a940be1cf2af 100644
--- a/drivers/acpi/arm64/iort.c
+++ b/drivers/acpi/arm64/iort.c
@@ -1144,56 +1144,18 @@ static int rc_dma_get_range(struct device *dev, u64
*size)
 }
 
 /**
- * iort_dma_setup() - Set-up device DMA parameters.
+ * iort_dma_get_ranges() - Look up DMA addressing limit for the device
+ * @dev: device to lookup
+ * @size: DMA range size result pointer
  *
- * @dev: device to configure
- * @dma_addr: device DMA address result pointer
- * @dma_size: DMA range size result pointer
+ * Return: 0 on success, an error otherwise.
  */
-void iort_dma_setup(struct device *dev, u64 *dma_addr, u64 *dma_size)
+int iort_dma_get_ranges(struct device *dev, u64 *size)
 {
-	u64 end, mask, dmaaddr = 0, size = 0, offset = 0;
-	int ret;
-
-	/*
-	 * If @dev is expected to be DMA-capable then the bus code that created
-	 * it should have initialised its dma_mask pointer by this point. For
-	 * now, we'll continue the legacy behaviour of coercing it to the
-	 * coherent mask if not, but we'll no longer do so quietly.
-	 */
-	if (!dev->dma_mask) {
-		dev_warn(dev, "DMA mask not set\n");
-		dev->dma_mask = &dev->coherent_dma_mask;
-	}
-
-	if (dev->coherent_dma_mask)
-		size = max(dev->coherent_dma_mask, dev->coherent_dma_mask + 1);
+	if (dev_is_pci(dev))
+		return rc_dma_get_range(dev, size);
 	else
-		size = 1ULL << 32;
-
-	ret = acpi_dma_get_range(dev, &dmaaddr, &offset, &size);
-	if (ret == -ENODEV)
-		ret = dev_is_pci(dev) ? rc_dma_get_range(dev, &size)
-				      : nc_dma_get_range(dev, &size);
-
-	if (!ret) {
-		/*
-		 * Limit coherent and dma mask based on size retrieved from
-		 * firmware.
-		 */
-		end = dmaaddr + size - 1;
-		mask = DMA_BIT_MASK(ilog2(end) + 1);
-		dev->bus_dma_limit = end;
-		dev->coherent_dma_mask = min(dev->coherent_dma_mask, mask);
-		*dev->dma_mask = min(*dev->dma_mask, mask);
-	}
-
-	*dma_addr = dmaaddr;
-	*dma_size = size;
-
-	ret = dma_direct_set_offset(dev, dmaaddr + offset, dmaaddr, size);
-
-	dev_dbg(dev, "dma_offset(%#08llx)%s\n", offset, ret ? "
failed!" : "");
+		return nc_dma_get_range(dev, size);
 }
 
 static void __init acpi_iort_register_irq(int hwirq, const char *name,
diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index bc973fbd70b2..e166916eb9db 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -1536,7 +1536,7 @@ int acpi_dma_configure_id(struct device *dev, enum
dev_dma_attr attr,
 		return 0;
 	}
 
-	iort_dma_setup(dev, &dma_addr, &size);
+	acpi_arch_dma_setup(dev, &dma_addr, &size);
 
 	iommu = iort_iommu_configure_id(dev, input_id);
 	if (PTR_ERR(iommu) == -EPROBE_DEFER)
-- 
2.31.1

Jean-Philippe Brucker

2021-Apr-23 11:38 UTC

head link

[PATCH v2 2/6] ACPI: Move IOMMU setup code out of IORT

Some of the IOMMU setup code in IORT is fairly generic and can be reused
by VIOT. Extract it from IORT.

Signed-off-by: Jean-Philippe Brucker <jean-philippe at linaro.org>
---
 include/acpi/acpi_bus.h   |  3 ++
 include/linux/acpi_iort.h |  8 ++---
 drivers/acpi/arm64/iort.c | 75 +++++----------------------------------
 drivers/acpi/scan.c       | 55 +++++++++++++++++++++++++++-
 4 files changed, 69 insertions(+), 72 deletions(-)

diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h
index 3a82faac5767..41f092a269f6 100644
--- a/include/acpi/acpi_bus.h
+++ b/include/acpi/acpi_bus.h
@@ -588,6 +588,9 @@ struct acpi_pci_root {
 
 bool acpi_dma_supported(struct acpi_device *adev);
 enum dev_dma_attr acpi_get_dma_attr(struct acpi_device *adev);
+int acpi_iommu_fwspec_init(struct device *dev, u32 id,
+			   struct fwnode_handle *fwnode,
+			   const struct iommu_ops *ops);
 int acpi_dma_get_range(struct device *dev, u64 *dma_addr, u64 *offset,
 		       u64 *size);
 int acpi_dma_configure_id(struct device *dev, enum dev_dma_attr attr,
diff --git a/include/linux/acpi_iort.h b/include/linux/acpi_iort.h
index f7f054833afd..f1f0842a2cb2 100644
--- a/include/linux/acpi_iort.h
+++ b/include/linux/acpi_iort.h
@@ -35,8 +35,7 @@ void acpi_configure_pmsi_domain(struct device *dev);
 int iort_pmsi_get_dev_id(struct device *dev, u32 *dev_id);
 /* IOMMU interface */
 int iort_dma_get_ranges(struct device *dev, u64 *size);
-const struct iommu_ops *iort_iommu_configure_id(struct device *dev,
-						const u32 *id_in);
+int iort_iommu_configure_id(struct device *dev, const u32 *id_in);
 int iort_iommu_msi_get_resv_regions(struct device *dev, struct list_head
*head);
 phys_addr_t acpi_iort_dma_get_max_cpu_address(void);
 #else
@@ -50,9 +49,8 @@ static inline void acpi_configure_pmsi_domain(struct device
*dev) { }
 /* IOMMU interface */
 static inline int iort_dma_get_ranges(struct device *dev, u64 *size)
 { return -ENODEV; }
-static inline const struct iommu_ops *iort_iommu_configure_id(
-				      struct device *dev, const u32 *id_in)
-{ return NULL; }
+static inline int iort_iommu_configure_id(struct device *dev, const u32 *id_in)
+{ return -ENODEV; }
 static inline
 int iort_iommu_msi_get_resv_regions(struct device *dev, struct list_head *head)
 { return 0; }
diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c
index a940be1cf2af..b5b021e064b6 100644
--- a/drivers/acpi/arm64/iort.c
+++ b/drivers/acpi/arm64/iort.c
@@ -806,23 +806,6 @@ static struct acpi_iort_node
*iort_get_msi_resv_iommu(struct device *dev)
 	return NULL;
 }
 
-static inline const struct iommu_ops *iort_fwspec_iommu_ops(struct device *dev)
-{
-	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
-
-	return (fwspec && fwspec->ops) ? fwspec->ops : NULL;
-}
-
-static inline int iort_add_device_replay(struct device *dev)
-{
-	int err = 0;
-
-	if (dev->bus && !device_iommu_mapped(dev))
-		err = iommu_probe_device(dev);
-
-	return err;
-}
-
 /**
  * iort_iommu_msi_get_resv_regions - Reserved region driver helper
  * @dev: Device from iommu_get_resv_regions()
@@ -900,18 +883,6 @@ static inline bool iort_iommu_driver_enabled(u8 type)
 	}
 }
 
-static int arm_smmu_iort_xlate(struct device *dev, u32 streamid,
-			       struct fwnode_handle *fwnode,
-			       const struct iommu_ops *ops)
-{
-	int ret = iommu_fwspec_init(dev, fwnode, ops);
-
-	if (!ret)
-		ret = iommu_fwspec_add_ids(dev, &streamid, 1);
-
-	return ret;
-}
-
 static bool iort_pci_rc_supports_ats(struct acpi_iort_node *node)
 {
 	struct acpi_iort_root_complex *pci_rc;
@@ -946,7 +917,7 @@ static int iort_iommu_xlate(struct device *dev, struct
acpi_iort_node *node,
 		return iort_iommu_driver_enabled(node->type) ?
 		       -EPROBE_DEFER : -ENODEV;
 
-	return arm_smmu_iort_xlate(dev, streamid, iort_fwnode, ops);
+	return acpi_iommu_fwspec_init(dev, streamid, iort_fwnode, ops);
 }
 
 struct iort_pci_alias_info {
@@ -1020,24 +991,14 @@ static int iort_nc_iommu_map_id(struct device *dev,
  * @dev: device to configure
  * @id_in: optional input id const value pointer
  *
- * Returns: iommu_ops pointer on configuration success
- *          NULL on configuration failure
+ * Returns: 0 on success, <0 on failure
  */
-const struct iommu_ops *iort_iommu_configure_id(struct device *dev,
-						const u32 *id_in)
+int iort_iommu_configure_id(struct device *dev, const u32 *id_in)
 {
 	struct acpi_iort_node *node;
-	const struct iommu_ops *ops;
+	const struct iommu_ops *ops = NULL;
 	int err = -ENODEV;
 
-	/*
-	 * If we already translated the fwspec there
-	 * is nothing left to do, return the iommu_ops.
-	 */
-	ops = iort_fwspec_iommu_ops(dev);
-	if (ops)
-		return ops;
-
 	if (dev_is_pci(dev)) {
 		struct iommu_fwspec *fwspec;
 		struct pci_bus *bus = to_pci_dev(dev)->bus;
@@ -1046,7 +1007,7 @@ const struct iommu_ops *iort_iommu_configure_id(struct
device *dev,
 		node = iort_scan_node(ACPI_IORT_NODE_PCI_ROOT_COMPLEX,
 				      iort_match_node_callback, &bus->dev);
 		if (!node)
-			return NULL;
+			return -ENODEV;
 
 		info.node = node;
 		err = pci_for_each_dma_alias(to_pci_dev(dev),
@@ -1059,7 +1020,7 @@ const struct iommu_ops *iort_iommu_configure_id(struct
device *dev,
 		node = iort_scan_node(ACPI_IORT_NODE_NAMED_COMPONENT,
 				      iort_match_node_callback, dev);
 		if (!node)
-			return NULL;
+			return -ENODEV;
 
 		err = id_in ? iort_nc_iommu_map_id(dev, node, id_in) :
 			      iort_nc_iommu_map(dev, node);
@@ -1068,32 +1029,14 @@ const struct iommu_ops *iort_iommu_configure_id(struct
device *dev,
 			iort_named_component_init(dev, node);
 	}
 
-	/*
-	 * If we have reason to believe the IOMMU driver missed the initial
-	 * add_device callback for dev, replay it to get things in order.
-	 */
-	if (!err) {
-		ops = iort_fwspec_iommu_ops(dev);
-		err = iort_add_device_replay(dev);
-	}
-
-	/* Ignore all other errors apart from EPROBE_DEFER */
-	if (err == -EPROBE_DEFER) {
-		ops = ERR_PTR(err);
-	} else if (err) {
-		dev_dbg(dev, "Adding to IOMMU failed: %d\n", err);
-		ops = NULL;
-	}
-
-	return ops;
+	return err;
 }
 
 #else
 int iort_iommu_msi_get_resv_regions(struct device *dev, struct list_head *head)
 { return 0; }
-const struct iommu_ops *iort_iommu_configure_id(struct device *dev,
-						const u32 *input_id)
-{ return NULL; }
+int iort_iommu_configure_id(struct device *dev, const u32 *input_id)
+{ return -ENODEV; }
 #endif
 
 static int nc_dma_get_range(struct device *dev, u64 *size)
diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index e166916eb9db..5924421075f6 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -9,6 +9,7 @@
 #include <linux/kernel.h>
 #include <linux/acpi.h>
 #include <linux/acpi_iort.h>
+#include <linux/iommu.h>
 #include <linux/signal.h>
 #include <linux/kthread.h>
 #include <linux/dmi.h>
@@ -1519,6 +1520,58 @@ int acpi_dma_get_range(struct device *dev, u64 *dma_addr,
u64 *offset,
 	return ret >= 0 ? 0 : ret;
 }
 
+int acpi_iommu_fwspec_init(struct device *dev, u32 id,
+			   struct fwnode_handle *fwnode,
+			   const struct iommu_ops *ops)
+{
+	int ret = iommu_fwspec_init(dev, fwnode, ops);
+
+	if (!ret)
+		ret = iommu_fwspec_add_ids(dev, &id, 1);
+
+	return ret;
+}
+
+static inline const struct iommu_ops *acpi_iommu_fwspec_ops(struct device *dev)
+{
+	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
+
+	return fwspec ? fwspec->ops : NULL;
+}
+
+static const struct iommu_ops *acpi_iommu_configure_id(struct device *dev,
+						       const u32 *id_in)
+{
+	int err;
+	const struct iommu_ops *ops;
+
+	/*
+	 * If we already translated the fwspec there is nothing left to do,
+	 * return the iommu_ops.
+	 */
+	ops = acpi_iommu_fwspec_ops(dev);
+	if (ops)
+		return ops;
+
+	err = iort_iommu_configure_id(dev, id_in);
+
+	/*
+	 * If we have reason to believe the IOMMU driver missed the initial
+	 * add_device callback for dev, replay it to get things in order.
+	 */
+	if (!err && dev->bus && !device_iommu_mapped(dev))
+		err = iommu_probe_device(dev);
+
+	/* Ignore all other errors apart from EPROBE_DEFER */
+	if (err == -EPROBE_DEFER) {
+		return ERR_PTR(err);
+	} else if (err) {
+		dev_dbg(dev, "Adding to IOMMU failed: %d\n", err);
+		return NULL;
+	}
+	return acpi_iommu_fwspec_ops(dev);
+}
+
 /**
  * acpi_dma_configure_id - Set-up DMA configuration for the device.
  * @dev: The pointer to the device
@@ -1538,7 +1591,7 @@ int acpi_dma_configure_id(struct device *dev, enum
dev_dma_attr attr,
 
 	acpi_arch_dma_setup(dev, &dma_addr, &size);
 
-	iommu = iort_iommu_configure_id(dev, input_id);
+	iommu = acpi_iommu_configure_id(dev, input_id);
 	if (PTR_ERR(iommu) == -EPROBE_DEFER)
 		return -EPROBE_DEFER;
 
-- 
2.31.1

Jean-Philippe Brucker

2021-Apr-23 11:38 UTC

head link

[PATCH v2 3/6] ACPI: Add driver for the VIOT table

The ACPI Virtual I/O Translation Table describes topology of
para-virtual platforms, similarly to vendor tables DMAR, IVRS and IORT.
For now it describes the relation between virtio-iommu and the endpoints
it manages.

Three steps are needed to configure DMA of endpoints:

(1) acpi_viot_init(): parse the VIOT table, find or create the fwnode
    associated to each vIOMMU device.

(2) When probing the vIOMMU device, the driver registers its IOMMU ops
    within the IOMMU subsystem. This step doesn't require any
    intervention from the VIOT driver.

(3) viot_iommu_configure(): before binding the endpoint to a driver,
    find the associated IOMMU ops. Register them, along with the
    endpoint ID, into the device's iommu_fwspec.

If step (3) happens before step (2), it is deferred until the IOMMU is
initialized, then retried.

Signed-off-by: Jean-Philippe Brucker <jean-philippe at linaro.org>
---
 drivers/acpi/Kconfig      |   3 +
 drivers/iommu/Kconfig     |   1 +
 drivers/acpi/Makefile     |   2 +
 include/linux/acpi_viot.h |  19 +++
 drivers/acpi/bus.c        |   2 +
 drivers/acpi/scan.c       |   3 +
 drivers/acpi/viot.c       | 350 ++++++++++++++++++++++++++++++++++++++
 MAINTAINERS               |   8 +
 8 files changed, 388 insertions(+)
 create mode 100644 include/linux/acpi_viot.h
 create mode 100644 drivers/acpi/viot.c

diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig
index eedec61e3476..3758c6940ed7 100644
--- a/drivers/acpi/Kconfig
+++ b/drivers/acpi/Kconfig
@@ -526,6 +526,9 @@ endif
 
 source "drivers/acpi/pmic/Kconfig"
 
+config ACPI_VIOT
+	bool
+
 endif	# ACPI
 
 config X86_PM_TIMER
diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig
index 1f111b399bca..aff8a4830dd1 100644
--- a/drivers/iommu/Kconfig
+++ b/drivers/iommu/Kconfig
@@ -403,6 +403,7 @@ config VIRTIO_IOMMU
 	depends on ARM64
 	select IOMMU_API
 	select INTERVAL_TREE
+	select ACPI_VIOT if ACPI
 	help
 	  Para-virtualised IOMMU driver with virtio.
 
diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile
index 700b41adf2db..a6e644c48987 100644
--- a/drivers/acpi/Makefile
+++ b/drivers/acpi/Makefile
@@ -118,3 +118,5 @@ video-objs			+= acpi_video.o video_detect.o
 obj-y				+= dptf/
 
 obj-$(CONFIG_ARM64)		+= arm64/
+
+obj-$(CONFIG_ACPI_VIOT)		+= viot.o
diff --git a/include/linux/acpi_viot.h b/include/linux/acpi_viot.h
new file mode 100644
index 000000000000..1eb8ee5b0e5f
--- /dev/null
+++ b/include/linux/acpi_viot.h
@@ -0,0 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#ifndef __ACPI_VIOT_H__
+#define __ACPI_VIOT_H__
+
+#include <linux/acpi.h>
+
+#ifdef CONFIG_ACPI_VIOT
+void __init acpi_viot_init(void);
+int viot_iommu_configure(struct device *dev);
+#else
+static inline void acpi_viot_init(void) {}
+static inline int viot_iommu_configure(struct device *dev)
+{
+	return -ENODEV;
+}
+#endif
+
+#endif /* __ACPI_VIOT_H__ */
diff --git a/drivers/acpi/bus.c b/drivers/acpi/bus.c
index be7da23fad76..b835ca702ff0 100644
--- a/drivers/acpi/bus.c
+++ b/drivers/acpi/bus.c
@@ -27,6 +27,7 @@
 #include <linux/dmi.h>
 #endif
 #include <linux/acpi_iort.h>
+#include <linux/acpi_viot.h>
 #include <linux/pci.h>
 #include <acpi/apei.h>
 #include <linux/suspend.h>
@@ -1339,6 +1340,7 @@ static int __init acpi_init(void)
 	pci_mmcfg_late_init();
 	acpi_iort_init();
 	acpi_scan_init();
+	acpi_viot_init();
 	acpi_ec_init();
 	acpi_debugfs_init();
 	acpi_sleep_proc_init();
diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index 5924421075f6..4db43c822ee7 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -9,6 +9,7 @@
 #include <linux/kernel.h>
 #include <linux/acpi.h>
 #include <linux/acpi_iort.h>
+#include <linux/acpi_viot.h>
 #include <linux/iommu.h>
 #include <linux/signal.h>
 #include <linux/kthread.h>
@@ -1554,6 +1555,8 @@ static const struct iommu_ops
*acpi_iommu_configure_id(struct device *dev,
 		return ops;
 
 	err = iort_iommu_configure_id(dev, id_in);
+	if (err && err != -EPROBE_DEFER)
+		err = viot_iommu_configure(dev);
 
 	/*
 	 * If we have reason to believe the IOMMU driver missed the initial
diff --git a/drivers/acpi/viot.c b/drivers/acpi/viot.c
new file mode 100644
index 000000000000..710e5a5eac70
--- /dev/null
+++ b/drivers/acpi/viot.c
@@ -0,0 +1,350 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Virtual I/O topology
+ */
+#define pr_fmt(fmt) "ACPI: VIOT: " fmt
+
+#include <linux/acpi_viot.h>
+#include <linux/dma-iommu.h>
+#include <linux/fwnode.h>
+#include <linux/iommu.h>
+#include <linux/list.h>
+#include <linux/pci.h>
+#include <linux/platform_device.h>
+
+struct viot_iommu {
+	/* Node offset within the table */
+	unsigned int			offset;
+	struct fwnode_handle		*fwnode;
+	struct list_head		list;
+};
+
+struct viot_endpoint {
+	union {
+		/* PCI range */
+		struct {
+			u16		segment_start;
+			u16		segment_end;
+			u16		bdf_start;
+			u16		bdf_end;
+		};
+		/* MMIO */
+		u64			address;
+	};
+	u32				endpoint_id;
+	struct viot_iommu		*viommu;
+	struct list_head		list;
+};
+
+static struct acpi_table_viot *viot;
+static LIST_HEAD(viot_iommus);
+static LIST_HEAD(viot_pci_ranges);
+static LIST_HEAD(viot_mmio_endpoints);
+
+static int __init viot_check_bounds(const struct acpi_viot_header *hdr)
+{
+	struct acpi_viot_header *start, *end, *hdr_end;
+
+	start = ACPI_ADD_PTR(struct acpi_viot_header, viot,
+			     max_t(size_t, sizeof(*viot), viot->node_offset));
+	end = ACPI_ADD_PTR(struct acpi_viot_header, viot, viot->header.length);
+	hdr_end = ACPI_ADD_PTR(struct acpi_viot_header, hdr, sizeof(*hdr));
+
+	if (hdr < start || hdr_end > end) {
+		pr_err(FW_BUG "Node pointer overflows\n");
+		return -EOVERFLOW;
+	}
+	if (hdr->length < sizeof(*hdr)) {
+		pr_err(FW_BUG "Empty node\n");
+		return -EINVAL;
+	}
+	return 0;
+}
+
+static int __init viot_get_pci_iommu_fwnode(struct viot_iommu *viommu,
+					    u16 segment, u16 bdf)
+{
+	struct pci_dev *pdev;
+	struct fwnode_handle *fwnode;
+
+	pdev = pci_get_domain_bus_and_slot(segment, PCI_BUS_NUM(bdf),
+					   bdf & 0xff);
+	if (!pdev) {
+		pr_err("Could not find PCI IOMMU\n");
+		return -ENODEV;
+	}
+
+	fwnode = pdev->dev.fwnode;
+	if (!fwnode) {
+		/*
+		 * PCI devices aren't necessarily described by ACPI. Create a
+		 * fwnode so the IOMMU subsystem can identify this device.
+		 */
+		fwnode = acpi_alloc_fwnode_static();
+		if (!fwnode) {
+			pci_dev_put(pdev);
+			return -ENOMEM;
+		}
+		set_primary_fwnode(&pdev->dev, fwnode);
+	}
+	viommu->fwnode = pdev->dev.fwnode;
+	pci_dev_put(pdev);
+	return 0;
+}
+
+static int __init viot_get_mmio_iommu_fwnode(struct viot_iommu *viommu,
+					     u64 address)
+{
+	struct acpi_device *adev;
+	struct resource res = {
+		.start	= address,
+		.end	= address,
+		.flags	= IORESOURCE_MEM,
+	};
+
+	adev = acpi_resource_consumer(&res);
+	if (!adev) {
+		pr_err("Could not find MMIO IOMMU\n");
+		return -EINVAL;
+	}
+	viommu->fwnode = &adev->fwnode;
+	return 0;
+}
+
+static struct viot_iommu * __init viot_get_iommu(unsigned int offset)
+{
+	int ret;
+	struct viot_iommu *viommu;
+	struct acpi_viot_header *hdr = ACPI_ADD_PTR(struct acpi_viot_header,
+						    viot, offset);
+	union {
+		struct acpi_viot_virtio_iommu_pci pci;
+		struct acpi_viot_virtio_iommu_mmio mmio;
+	} *node = (void *)hdr;
+
+	list_for_each_entry(viommu, &viot_iommus, list)
+		if (viommu->offset == offset)
+			return viommu;
+
+	if (viot_check_bounds(hdr))
+		return NULL;
+
+	viommu = kzalloc(sizeof(*viommu), GFP_KERNEL);
+	if (!viommu)
+		return NULL;
+
+	viommu->offset = offset;
+	switch (hdr->type) {
+	case ACPI_VIOT_NODE_VIRTIO_IOMMU_PCI:
+		if (hdr->length < sizeof(node->pci))
+			goto err_free;
+
+		ret = viot_get_pci_iommu_fwnode(viommu, node->pci.segment,
+						node->pci.bdf);
+		break;
+	case ACPI_VIOT_NODE_VIRTIO_IOMMU_MMIO:
+		if (hdr->length < sizeof(node->mmio))
+			goto err_free;
+
+		ret = viot_get_mmio_iommu_fwnode(viommu,
+						 node->mmio.base_address);
+		break;
+	default:
+		ret = -EINVAL;
+	}
+	if (ret)
+		goto err_free;
+
+	list_add(&viommu->list, &viot_iommus);
+	return viommu;
+
+err_free:
+	kfree(viommu);
+	return NULL;
+}
+
+static int __init viot_parse_node(const struct acpi_viot_header *hdr)
+{
+	int ret = -EINVAL;
+	struct list_head *list;
+	struct viot_endpoint *ep;
+	union {
+		struct acpi_viot_mmio mmio;
+		struct acpi_viot_pci_range pci;
+	} *node = (void *)hdr;
+
+	if (viot_check_bounds(hdr))
+		return -EINVAL;
+
+	if (hdr->type == ACPI_VIOT_NODE_VIRTIO_IOMMU_PCI ||
+	    hdr->type == ACPI_VIOT_NODE_VIRTIO_IOMMU_MMIO)
+		return 0;
+
+	ep = kzalloc(sizeof(*ep), GFP_KERNEL);
+	if (!ep)
+		return -ENOMEM;
+
+	switch (hdr->type) {
+	case ACPI_VIOT_NODE_PCI_RANGE:
+		if (hdr->length < sizeof(node->pci)) {
+			pr_err(FW_BUG "Invalid PCI node size\n");
+			goto err_free;
+		}
+
+		ep->segment_start = node->pci.segment_start;
+		ep->segment_end = node->pci.segment_end;
+		ep->bdf_start = node->pci.bdf_start;
+		ep->bdf_end = node->pci.bdf_end;
+		ep->endpoint_id = node->pci.endpoint_start;
+		ep->viommu = viot_get_iommu(node->pci.output_node);
+		list = &viot_pci_ranges;
+		break;
+	case ACPI_VIOT_NODE_MMIO:
+		if (hdr->length < sizeof(node->mmio)) {
+			pr_err(FW_BUG "Invalid MMIO node size\n");
+			goto err_free;
+		}
+
+		ep->address = node->mmio.base_address;
+		ep->endpoint_id = node->mmio.endpoint;
+		ep->viommu = viot_get_iommu(node->mmio.output_node);
+		list = &viot_mmio_endpoints;
+		break;
+	default:
+		pr_warn("Unsupported node %x\n", hdr->type);
+		ret = 0;
+		goto err_free;
+	}
+
+	/*
+	 * To be compatible with future versions of the table which may include
+	 * other node types, keep parsing.
+	 */
+	if (!ep->viommu) {
+		pr_warn("No IOMMU node found\n");
+		ret = 0;
+		goto err_free;
+	}
+
+	list_add(&ep->list, list);
+	return 0;
+
+err_free:
+	kfree(ep);
+	return ret;
+}
+
+/**
+ * acpi_viot_init - Parse the VIOT table
+ *
+ * Parse the VIOT table, prepare the list of endpoints to be used during DMA
+ * setup of devices.
+ */
+void __init acpi_viot_init(void)
+{
+	int i;
+	acpi_status status;
+	struct acpi_table_header *hdr;
+	struct acpi_viot_header *node;
+
+	status = acpi_get_table(ACPI_SIG_VIOT, 0, &hdr);
+	if (ACPI_FAILURE(status)) {
+		if (status != AE_NOT_FOUND) {
+			const char *msg = acpi_format_exception(status);
+
+			pr_err("Failed to get table, %s\n", msg);
+		}
+		return;
+	}
+
+	viot = (void *)hdr;
+
+	node = ACPI_ADD_PTR(struct acpi_viot_header, viot, viot->node_offset);
+	for (i = 0; i < viot->node_count; i++) {
+		if (viot_parse_node(node))
+			return;
+
+		node = ACPI_ADD_PTR(struct acpi_viot_header, node,
+				    node->length);
+	}
+}
+
+static int viot_dev_iommu_init(struct device *dev, struct viot_iommu *viommu,
+			       u32 epid)
+{
+	const struct iommu_ops *ops;
+
+	if (!viommu)
+		return -ENODEV;
+
+	/* We're not translating ourself */
+	if (viommu->fwnode == dev->fwnode)
+		return -EINVAL;
+
+	ops = iommu_ops_from_fwnode(viommu->fwnode);
+	if (!ops)
+		return IS_ENABLED(CONFIG_VIRTIO_IOMMU) ?
+			-EPROBE_DEFER : -ENODEV;
+
+	return acpi_iommu_fwspec_init(dev, epid, viommu->fwnode, ops);
+}
+
+static int viot_pci_dev_iommu_init(struct pci_dev *pdev, u16 dev_id, void
*data)
+{
+	u32 epid;
+	struct viot_endpoint *ep;
+	u32 domain_nr = pci_domain_nr(pdev->bus);
+
+	list_for_each_entry(ep, &viot_pci_ranges, list) {
+		if (domain_nr >= ep->segment_start &&
+		    domain_nr <= ep->segment_end &&
+		    dev_id >= ep->bdf_start &&
+		    dev_id <= ep->bdf_end) {
+			epid = ((domain_nr - ep->segment_start) << 16) +
+				dev_id - ep->bdf_start + ep->endpoint_id;
+
+			/*
+			 * If we found a PCI range managed by the viommu, we're
+			 * the one that has to request ACS.
+			 */
+			pci_request_acs();
+
+			return viot_dev_iommu_init(&pdev->dev, ep->viommu,
+						   epid);
+		}
+	}
+	return -ENODEV;
+}
+
+static int viot_mmio_dev_iommu_init(struct platform_device *pdev)
+{
+	struct resource *mem;
+	struct viot_endpoint *ep;
+
+	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!mem)
+		return -ENODEV;
+
+	list_for_each_entry(ep, &viot_mmio_endpoints, list) {
+		if (ep->address == mem->start)
+			return viot_dev_iommu_init(&pdev->dev, ep->viommu,
+						   ep->endpoint_id);
+	}
+	return -ENODEV;
+}
+
+/**
+ * viot_iommu_configure - Setup IOMMU ops for an endpoint described by VIOT
+ * @dev: the endpoint
+ *
+ * Return: 0 on success, <0 on failure
+ */
+int viot_iommu_configure(struct device *dev)
+{
+	if (dev_is_pci(dev))
+		return pci_for_each_dma_alias(to_pci_dev(dev),
+					      viot_pci_dev_iommu_init, NULL);
+	else if (dev_is_platform(dev))
+		return viot_mmio_dev_iommu_init(to_platform_device(dev));
+	return -ENODEV;
+}
diff --git a/MAINTAINERS b/MAINTAINERS
index 6b1560c45e2a..1a018afff162 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -431,6 +431,14 @@ W:	https://01.org/linux-acpi
 B:	https://bugzilla.kernel.org
 F:	drivers/acpi/acpi_video.c
 
+ACPI VIOT DRIVER
+M:	Jean-Philippe Brucker <jean-philippe at linaro.org>
+L:	linux-acpi at vger.kernel.org
+L:	iommu at lists.linux-foundation.org
+S:	Maintained
+F:	drivers/acpi/viot.c
+F:	include/linux/acpi_viot.h
+
 ACPI WMI DRIVER
 L:	platform-driver-x86 at vger.kernel.org
 S:	Orphan
-- 
2.31.1

Jean-Philippe Brucker

2021-Apr-23 11:38 UTC

head link

[PATCH v2 4/6] iommu/dma: Pass address limit rather than size to iommu_setup_dma_ops()

Passing a 64-bit address width to iommu_setup_dma_ops() is valid on
virtual platforms, but isn't currently possible. The overflow check in
iommu_dma_init_domain() prevents this even when @dma_base isn't 0. Pass
a limit address instead of a size, so callers don't have to fake a size
to work around the check.

Signed-off-by: Jean-Philippe Brucker <jean-philippe at linaro.org>
---
 include/linux/dma-iommu.h   |  4 ++--
 arch/arm64/mm/dma-mapping.c |  2 +-
 drivers/iommu/amd/iommu.c   |  2 +-
 drivers/iommu/dma-iommu.c   | 12 ++++++------
 drivers/iommu/intel/iommu.c |  2 +-
 5 files changed, 11 insertions(+), 11 deletions(-)

diff --git a/include/linux/dma-iommu.h b/include/linux/dma-iommu.h
index 6e75a2d689b4..758ca4694257 100644
--- a/include/linux/dma-iommu.h
+++ b/include/linux/dma-iommu.h
@@ -19,7 +19,7 @@ int iommu_get_msi_cookie(struct iommu_domain *domain,
dma_addr_t base);
 void iommu_put_dma_cookie(struct iommu_domain *domain);
 
 /* Setup call for arch DMA mapping code */
-void iommu_setup_dma_ops(struct device *dev, u64 dma_base, u64 size);
+void iommu_setup_dma_ops(struct device *dev, u64 dma_base, u64 dma_limit);
 
 /* The DMA API isn't _quite_ the whole story, though... */
 /*
@@ -50,7 +50,7 @@ struct msi_msg;
 struct device;
 
 static inline void iommu_setup_dma_ops(struct device *dev, u64 dma_base,
-		u64 size)
+				       u64 dma_limit)
 {
 }
 
diff --git a/arch/arm64/mm/dma-mapping.c b/arch/arm64/mm/dma-mapping.c
index 93e87b287556..83f4f4bad5e4 100644
--- a/arch/arm64/mm/dma-mapping.c
+++ b/arch/arm64/mm/dma-mapping.c
@@ -50,7 +50,7 @@ void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64
size,
 
 	dev->dma_coherent = coherent;
 	if (iommu)
-		iommu_setup_dma_ops(dev, dma_base, size);
+		iommu_setup_dma_ops(dev, dma_base, size - dma_base - 1);
 
 #ifdef CONFIG_XEN
 	if (xen_initial_domain())
diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c
index 67da96d5b3c2..50041df43391 100644
--- a/drivers/iommu/amd/iommu.c
+++ b/drivers/iommu/amd/iommu.c
@@ -1713,7 +1713,7 @@ static void amd_iommu_probe_finalize(struct device *dev)
 	/* Domains are initialized for this device - have a look what we ended up with
*/
 	domain = iommu_get_domain_for_dev(dev);
 	if (domain->type == IOMMU_DOMAIN_DMA)
-		iommu_setup_dma_ops(dev, IOVA_START_PFN << PAGE_SHIFT, 0);
+		iommu_setup_dma_ops(dev, IOVA_START_PFN << PAGE_SHIFT, U64_MAX);
 	else
 		set_dma_ops(dev, NULL);
 }
diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c
index 7bcdd1205535..c62e19bed302 100644
--- a/drivers/iommu/dma-iommu.c
+++ b/drivers/iommu/dma-iommu.c
@@ -319,16 +319,16 @@ static bool dev_is_untrusted(struct device *dev)
  * iommu_dma_init_domain - Initialise a DMA mapping domain
  * @domain: IOMMU domain previously prepared by iommu_get_dma_cookie()
  * @base: IOVA at which the mappable address space starts
- * @size: Size of IOVA space
+ * @limit: Last address of the IOVA space
  * @dev: Device the domain is being initialised for
  *
- * @base and @size should be exact multiples of IOMMU page granularity to
+ * @base and @limit + 1 should be exact multiples of IOMMU page granularity to
  * avoid rounding surprises. If necessary, we reserve the page at address 0
  * to ensure it is an invalid IOVA. It is safe to reinitialise a domain, but
  * any change which could make prior IOVAs invalid will fail.
  */
 static int iommu_dma_init_domain(struct iommu_domain *domain, dma_addr_t base,
-		u64 size, struct device *dev)
+				 dma_addr_t limit, struct device *dev)
 {
 	struct iommu_dma_cookie *cookie = domain->iova_cookie;
 	unsigned long order, base_pfn;
@@ -346,7 +346,7 @@ static int iommu_dma_init_domain(struct iommu_domain
*domain, dma_addr_t base,
 	/* Check the domain allows at least some access to the device... */
 	if (domain->geometry.force_aperture) {
 		if (base > domain->geometry.aperture_end ||
-		    base + size <= domain->geometry.aperture_start) {
+		    limit < domain->geometry.aperture_start) {
 			pr_warn("specified DMA range outside IOMMU capability\n");
 			return -EFAULT;
 		}
@@ -1308,7 +1308,7 @@ static const struct dma_map_ops iommu_dma_ops = {
  * The IOMMU core code allocates the default DMA domain, which the underlying
  * IOMMU driver needs to support via the dma-iommu layer.
  */
-void iommu_setup_dma_ops(struct device *dev, u64 dma_base, u64 size)
+void iommu_setup_dma_ops(struct device *dev, u64 dma_base, u64 dma_limit)
 {
 	struct iommu_domain *domain = iommu_get_domain_for_dev(dev);
 
@@ -1320,7 +1320,7 @@ void iommu_setup_dma_ops(struct device *dev, u64 dma_base,
u64 size)
 	 * underlying IOMMU driver needs to support via the dma-iommu layer.
 	 */
 	if (domain->type == IOMMU_DOMAIN_DMA) {
-		if (iommu_dma_init_domain(domain, dma_base, size, dev))
+		if (iommu_dma_init_domain(domain, dma_base, dma_limit, dev))
 			goto out_err;
 		dev->dma_ops = &iommu_dma_ops;
 	}
diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index 708f430af1c4..39a4e672b1c2 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -5166,7 +5166,7 @@ static void intel_iommu_probe_finalize(struct device *dev)
 
 	if (domain && domain->type == IOMMU_DOMAIN_DMA)
 		iommu_setup_dma_ops(dev, base,
-				    __DOMAIN_MAX_ADDR(dmar_domain->gaw) - base);
+				    __DOMAIN_MAX_ADDR(dmar_domain->gaw));
 	else
 		set_dma_ops(dev, NULL);
 }
-- 
2.31.1

Jean-Philippe Brucker

2021-Apr-23 11:38 UTC

head link

[PATCH v2 5/6] iommu/dma: Simplify calls to iommu_setup_dma_ops()

dma-iommu uses the address bounds described in domain->geometry during
IOVA allocation. The address size parameters of iommu_setup_dma_ops()
are useful for describing additional limits set by the platform
firmware, but aren't needed for drivers that call this function from
probe_finalize(). The base parameter can be zero because dma-iommu
already removes the first IOVA page, and the limit parameter can be
U64_MAX because it's only checked against the domain geometry. Simplify
calls to iommu_setup_dma_ops().

Signed-off-by: Jean-Philippe Brucker <jean-philippe at linaro.org>
---
 drivers/iommu/amd/iommu.c   |  9 +--------
 drivers/iommu/dma-iommu.c   |  4 +++-
 drivers/iommu/intel/iommu.c | 10 +---------
 3 files changed, 5 insertions(+), 18 deletions(-)

diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c
index 50041df43391..bbb09840cf40 100644
--- a/drivers/iommu/amd/iommu.c
+++ b/drivers/iommu/amd/iommu.c
@@ -1708,14 +1708,7 @@ static struct iommu_device *amd_iommu_probe_device(struct
device *dev)
 
 static void amd_iommu_probe_finalize(struct device *dev)
 {
-	struct iommu_domain *domain;
-
-	/* Domains are initialized for this device - have a look what we ended up with
*/
-	domain = iommu_get_domain_for_dev(dev);
-	if (domain->type == IOMMU_DOMAIN_DMA)
-		iommu_setup_dma_ops(dev, IOVA_START_PFN << PAGE_SHIFT, U64_MAX);
-	else
-		set_dma_ops(dev, NULL);
+	iommu_setup_dma_ops(dev, 0, U64_MAX);
 }
 
 static void amd_iommu_release_device(struct device *dev)
diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c
index c62e19bed302..175f8eaeb5b3 100644
--- a/drivers/iommu/dma-iommu.c
+++ b/drivers/iommu/dma-iommu.c
@@ -1322,7 +1322,9 @@ void iommu_setup_dma_ops(struct device *dev, u64 dma_base,
u64 dma_limit)
 	if (domain->type == IOMMU_DOMAIN_DMA) {
 		if (iommu_dma_init_domain(domain, dma_base, dma_limit, dev))
 			goto out_err;
-		dev->dma_ops = &iommu_dma_ops;
+		set_dma_ops(dev, &iommu_dma_ops);
+	} else {
+		set_dma_ops(dev, NULL);
 	}
 
 	return;
diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index 39a4e672b1c2..c6fe11d3624e 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -5160,15 +5160,7 @@ static void intel_iommu_release_device(struct device
*dev)
 
 static void intel_iommu_probe_finalize(struct device *dev)
 {
-	dma_addr_t base = IOVA_START_PFN << VTD_PAGE_SHIFT;
-	struct iommu_domain *domain = iommu_get_domain_for_dev(dev);
-	struct dmar_domain *dmar_domain = to_dmar_domain(domain);
-
-	if (domain && domain->type == IOMMU_DOMAIN_DMA)
-		iommu_setup_dma_ops(dev, base,
-				    __DOMAIN_MAX_ADDR(dmar_domain->gaw));
-	else
-		set_dma_ops(dev, NULL);
+	iommu_setup_dma_ops(dev, 0, U64_MAX);
 }
 
 static void intel_iommu_get_resv_regions(struct device *device,
-- 
2.31.1

Jean-Philippe Brucker

2021-Apr-23 11:38 UTC

head link

[PATCH v2 6/6] iommu/virtio: Enable x86 support

With the VIOT support in place, x86 platforms can now use the
virtio-iommu.

Because the other x86 IOMMU drivers aren't yet ready to use the
acpi_dma_setup() path, x86 doesn't implement arch_setup_dma_ops() at the
moment. Similarly to Vt-d and AMD IOMMU, call iommu_setup_dma_ops() from
probe_finalize().

Acked-by: Joerg Roedel <jroedel at suse.de>
Signed-off-by: Jean-Philippe Brucker <jean-philippe at linaro.org>
---
 drivers/iommu/Kconfig        | 3 ++-
 drivers/iommu/dma-iommu.c    | 1 +
 drivers/iommu/virtio-iommu.c | 8 ++++++++
 3 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig
index aff8a4830dd1..07b7c25cbed8 100644
--- a/drivers/iommu/Kconfig
+++ b/drivers/iommu/Kconfig
@@ -400,8 +400,9 @@ config HYPERV_IOMMU
 config VIRTIO_IOMMU
 	tristate "Virtio IOMMU driver"
 	depends on VIRTIO
-	depends on ARM64
+	depends on (ARM64 || X86)
 	select IOMMU_API
+	select IOMMU_DMA
 	select INTERVAL_TREE
 	select ACPI_VIOT if ACPI
 	help
diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c
index 175f8eaeb5b3..46ed43c400cf 100644
--- a/drivers/iommu/dma-iommu.c
+++ b/drivers/iommu/dma-iommu.c
@@ -1332,6 +1332,7 @@ void iommu_setup_dma_ops(struct device *dev, u64 dma_base,
u64 dma_limit)
 	 pr_warn("Failed to set up IOMMU for device %s; retaining platform DMA
ops\n",
 		 dev_name(dev));
 }
+EXPORT_SYMBOL_GPL(iommu_setup_dma_ops);
 
 static struct iommu_dma_msi_page *iommu_dma_get_msi_page(struct device *dev,
 		phys_addr_t msi_addr, struct iommu_domain *domain)
diff --git a/drivers/iommu/virtio-iommu.c b/drivers/iommu/virtio-iommu.c
index 29a397c2d12f..8be546a338e7 100644
--- a/drivers/iommu/virtio-iommu.c
+++ b/drivers/iommu/virtio-iommu.c
@@ -1027,6 +1027,13 @@ static struct iommu_device *viommu_probe_device(struct
device *dev)
 	return ERR_PTR(ret);
 }
 
+static void viommu_probe_finalize(struct device *dev)
+{
+#ifndef CONFIG_ARCH_HAS_SETUP_DMA_OPS
+	iommu_setup_dma_ops(dev, 0, U64_MAX);
+#endif
+}
+
 static void viommu_release_device(struct device *dev)
 {
 	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
@@ -1063,6 +1070,7 @@ static struct iommu_ops viommu_ops = {
 	.iova_to_phys		= viommu_iova_to_phys,
 	.iotlb_sync		= viommu_iotlb_sync,
 	.probe_device		= viommu_probe_device,
+	.probe_finalize		= viommu_probe_finalize,
 	.release_device		= viommu_release_device,
 	.device_group		= viommu_device_group,
 	.get_resv_regions	= viommu_get_resv_regions,
-- 
2.31.1

Michael S. Tsirkin

2021-May-14 12:34 UTC

head link

[PATCH v2 6/6] iommu/virtio: Enable x86 support

On Fri, Apr 23, 2021 at 01:38:37PM +0200, Jean-Philippe Brucker
wrote:> With the VIOT support in place, x86 platforms can now use the
> virtio-iommu.
> 
> Because the other x86 IOMMU drivers aren't yet ready to use the
> acpi_dma_setup() path, x86 doesn't implement arch_setup_dma_ops() at
the
> moment. Similarly to Vt-d and AMD IOMMU, call iommu_setup_dma_ops() from
> probe_finalize().
> 
> Acked-by: Joerg Roedel <jroedel at suse.de>
> Signed-off-by: Jean-Philippe Brucker <jean-philippe at linaro.org>
Acked-by: Michael S. Tsirkin <mst at redhat.com>
> ---
>  drivers/iommu/Kconfig        | 3 ++-
>  drivers/iommu/dma-iommu.c    | 1 +
>  drivers/iommu/virtio-iommu.c | 8 ++++++++
>  3 files changed, 11 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig
> index aff8a4830dd1..07b7c25cbed8 100644
> --- a/drivers/iommu/Kconfig
> +++ b/drivers/iommu/Kconfig
> @@ -400,8 +400,9 @@ config HYPERV_IOMMU
>  config VIRTIO_IOMMU
>  	tristate "Virtio IOMMU driver"
>  	depends on VIRTIO
> -	depends on ARM64
> +	depends on (ARM64 || X86)
>  	select IOMMU_API
> +	select IOMMU_DMA
>  	select INTERVAL_TREE
>  	select ACPI_VIOT if ACPI
>  	help
> diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c
> index 175f8eaeb5b3..46ed43c400cf 100644
> --- a/drivers/iommu/dma-iommu.c
> +++ b/drivers/iommu/dma-iommu.c
> @@ -1332,6 +1332,7 @@ void iommu_setup_dma_ops(struct device *dev, u64
dma_base, u64 dma_limit)
>  	 pr_warn("Failed to set up IOMMU for device %s; retaining platform
DMA ops\n",
>  		 dev_name(dev));
>  }
> +EXPORT_SYMBOL_GPL(iommu_setup_dma_ops);
>  
>  static struct iommu_dma_msi_page *iommu_dma_get_msi_page(struct device
*dev,
>  		phys_addr_t msi_addr, struct iommu_domain *domain)
> diff --git a/drivers/iommu/virtio-iommu.c b/drivers/iommu/virtio-iommu.c
> index 29a397c2d12f..8be546a338e7 100644
> --- a/drivers/iommu/virtio-iommu.c
> +++ b/drivers/iommu/virtio-iommu.c
> @@ -1027,6 +1027,13 @@ static struct iommu_device
*viommu_probe_device(struct device *dev)
>  	return ERR_PTR(ret);
>  }
>  
> +static void viommu_probe_finalize(struct device *dev)
> +{
> +#ifndef CONFIG_ARCH_HAS_SETUP_DMA_OPS
> +	iommu_setup_dma_ops(dev, 0, U64_MAX);
> +#endif
> +}
> +
>  static void viommu_release_device(struct device *dev)
>  {
>  	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
> @@ -1063,6 +1070,7 @@ static struct iommu_ops viommu_ops = {
>  	.iova_to_phys		= viommu_iova_to_phys,
>  	.iotlb_sync		= viommu_iotlb_sync,
>  	.probe_device		= viommu_probe_device,
> +	.probe_finalize		= viommu_probe_finalize,
>  	.release_device		= viommu_release_device,
>  	.device_group		= viommu_device_group,
>  	.get_resv_regions	= viommu_get_resv_regions,
> -- 
> 2.31.1

Michael S. Tsirkin

2021-May-14 12:35 UTC

head link

[PATCH v2 0/6] Add support for ACPI VIOT

On Fri, Apr 23, 2021 at 01:38:31PM +0200, Jean-Philippe Brucker
wrote:> Add a driver for the ACPI VIOT table, which provides topology
> information for para-virtual platforms. Enable virtio-iommu on
> non-devicetree platforms, including x86.
Acked-by: Michael S. Tsirkin <mst at redhat.com>

Mostly ACPI stuff so I assume it's best to merge through that tree.
> Since v1 [1]:
> * The VIOT header definitions have been picked for v5.13
> * Share more code with IORT. Patches 1 and 2 extract the common code
>   from IORT.
> * Simplify the VIOT driver. Use the existing fwnode infrastructure
>   instead of adding hooks to the IOMMU driver.
> 
> You can find a QEMU implementation at [2], with extra support for
> testing all VIOT nodes including MMIO-based endpoints and IOMMU. This
> series, based on linux-next, is at [3]
> 
> [1]
https://lore.kernel.org/linux-iommu/20210316191652.3401335-1-jean-philippe at
linaro.org/
> [2] https://jpbrucker.net/git/qemu/log/?h=virtio-iommu/acpi
> [3] https://jpbrucker.net/git/linux/log/?h=virtio-iommu/acpi
> 
> Jean-Philippe Brucker (6):
>   ACPI: arm64: Move DMA setup operations out of IORT
>   ACPI: Move IOMMU setup code out of IORT
>   ACPI: Add driver for the VIOT table
>   iommu/dma: Pass address limit rather than size to
>     iommu_setup_dma_ops()
>   iommu/dma: Simplify calls to iommu_setup_dma_ops()
>   iommu/virtio: Enable x86 support
> 
>  drivers/acpi/Kconfig         |   3 +
>  drivers/iommu/Kconfig        |   4 +-
>  drivers/acpi/Makefile        |   2 +
>  drivers/acpi/arm64/Makefile  |   1 +
>  include/acpi/acpi_bus.h      |   3 +
>  include/linux/acpi.h         |   3 +
>  include/linux/acpi_iort.h    |  14 +-
>  include/linux/acpi_viot.h    |  19 ++
>  include/linux/dma-iommu.h    |   4 +-
>  arch/arm64/mm/dma-mapping.c  |   2 +-
>  drivers/acpi/arm64/dma.c     |  50 +++++
>  drivers/acpi/arm64/iort.c    | 129 ++-----------
>  drivers/acpi/bus.c           |   2 +
>  drivers/acpi/scan.c          |  60 +++++-
>  drivers/acpi/viot.c          | 350 +++++++++++++++++++++++++++++++++++
>  drivers/iommu/amd/iommu.c    |   9 +-
>  drivers/iommu/dma-iommu.c    |  17 +-
>  drivers/iommu/intel/iommu.c  |  10 +-
>  drivers/iommu/virtio-iommu.c |   8 +
>  MAINTAINERS                  |   8 +
>  20 files changed, 548 insertions(+), 150 deletions(-)
>  create mode 100644 include/linux/acpi_viot.h
>  create mode 100644 drivers/acpi/arm64/dma.c
>  create mode 100644 drivers/acpi/viot.c
> 
> -- 
> 2.31.1

Joerg Roedel

2021-May-17 11:51 UTC

head link

[PATCH v2 0/6] Add support for ACPI VIOT

Hi Jean-Philippe,

On Fri, Apr 23, 2021 at 01:38:31PM +0200, Jean-Philippe Brucker
wrote:> Jean-Philippe Brucker (6):
>   ACPI: arm64: Move DMA setup operations out of IORT
>   ACPI: Move IOMMU setup code out of IORT
>   ACPI: Add driver for the VIOT table
>   iommu/dma: Pass address limit rather than size to
>     iommu_setup_dma_ops()
>   iommu/dma: Simplify calls to iommu_setup_dma_ops()
>   iommu/virtio: Enable x86 support
This looks good to me, I think this all can go through the IOMMU tree?
In this case I will apply them once the ACPI parts have the Acks
maintainers ack.

Regards,

	Joerg

Rafael J. Wysocki

2021-May-21 16:39 UTC

head link

[PATCH v2 3/6] ACPI: Add driver for the VIOT table

On Fri, Apr 23, 2021 at 1:57 PM Jean-Philippe Brucker
<jean-philippe at linaro.org> wrote:>
> The ACPI Virtual I/O Translation Table describes topology of
> para-virtual platforms, similarly to vendor tables DMAR, IVRS and IORT.
> For now it describes the relation between virtio-iommu and the endpoints
> it manages.
>
> Three steps are needed to configure DMA of endpoints:
>
> (1) acpi_viot_init(): parse the VIOT table, find or create the fwnode
>     associated to each vIOMMU device.
>
> (2) When probing the vIOMMU device, the driver registers its IOMMU ops
>     within the IOMMU subsystem. This step doesn't require any
>     intervention from the VIOT driver.
>
> (3) viot_iommu_configure(): before binding the endpoint to a driver,
>     find the associated IOMMU ops. Register them, along with the
>     endpoint ID, into the device's iommu_fwspec.
>
> If step (3) happens before step (2), it is deferred until the IOMMU is
> initialized, then retried.
>
> Signed-off-by: Jean-Philippe Brucker <jean-philippe at linaro.org>
> ---
>  drivers/acpi/Kconfig      |   3 +
>  drivers/iommu/Kconfig     |   1 +
>  drivers/acpi/Makefile     |   2 +
>  include/linux/acpi_viot.h |  19 +++
>  drivers/acpi/bus.c        |   2 +
>  drivers/acpi/scan.c       |   3 +
>  drivers/acpi/viot.c       | 350 ++++++++++++++++++++++++++++++++++++++
>  MAINTAINERS               |   8 +
>  8 files changed, 388 insertions(+)
>  create mode 100644 include/linux/acpi_viot.h
>  create mode 100644 drivers/acpi/viot.c
>
> diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig
> index eedec61e3476..3758c6940ed7 100644
> --- a/drivers/acpi/Kconfig
> +++ b/drivers/acpi/Kconfig
> @@ -526,6 +526,9 @@ endif
>
>  source "drivers/acpi/pmic/Kconfig"
>
> +config ACPI_VIOT
> +       bool
> +
>  endif  # ACPI
>
>  config X86_PM_TIMER
> diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig
> index 1f111b399bca..aff8a4830dd1 100644
> --- a/drivers/iommu/Kconfig
> +++ b/drivers/iommu/Kconfig
> @@ -403,6 +403,7 @@ config VIRTIO_IOMMU
>         depends on ARM64
>         select IOMMU_API
>         select INTERVAL_TREE
> +       select ACPI_VIOT if ACPI
>         help
>           Para-virtualised IOMMU driver with virtio.
>
> diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile
> index 700b41adf2db..a6e644c48987 100644
> --- a/drivers/acpi/Makefile
> +++ b/drivers/acpi/Makefile
> @@ -118,3 +118,5 @@ video-objs                  += acpi_video.o
video_detect.o
>  obj-y                          += dptf/
>
>  obj-$(CONFIG_ARM64)            += arm64/
> +
> +obj-$(CONFIG_ACPI_VIOT)                += viot.o
> diff --git a/include/linux/acpi_viot.h b/include/linux/acpi_viot.h
> new file mode 100644
> index 000000000000..1eb8ee5b0e5f
> --- /dev/null
> +++ b/include/linux/acpi_viot.h
> @@ -0,0 +1,19 @@
> +/* SPDX-License-Identifier: GPL-2.0-only */
> +
> +#ifndef __ACPI_VIOT_H__
> +#define __ACPI_VIOT_H__
> +
> +#include <linux/acpi.h>
> +
> +#ifdef CONFIG_ACPI_VIOT
> +void __init acpi_viot_init(void);
> +int viot_iommu_configure(struct device *dev);
> +#else
> +static inline void acpi_viot_init(void) {}
> +static inline int viot_iommu_configure(struct device *dev)
> +{
> +       return -ENODEV;
> +}
> +#endif
> +
> +#endif /* __ACPI_VIOT_H__ */
> diff --git a/drivers/acpi/bus.c b/drivers/acpi/bus.c
> index be7da23fad76..b835ca702ff0 100644
> --- a/drivers/acpi/bus.c
> +++ b/drivers/acpi/bus.c
> @@ -27,6 +27,7 @@
>  #include <linux/dmi.h>
>  #endif
>  #include <linux/acpi_iort.h>
> +#include <linux/acpi_viot.h>
>  #include <linux/pci.h>
>  #include <acpi/apei.h>
>  #include <linux/suspend.h>
> @@ -1339,6 +1340,7 @@ static int __init acpi_init(void)
>         pci_mmcfg_late_init();
>         acpi_iort_init();
>         acpi_scan_init();
> +       acpi_viot_init();
>         acpi_ec_init();
>         acpi_debugfs_init();
>         acpi_sleep_proc_init();
> diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
> index 5924421075f6..4db43c822ee7 100644
> --- a/drivers/acpi/scan.c
> +++ b/drivers/acpi/scan.c
> @@ -9,6 +9,7 @@
>  #include <linux/kernel.h>
>  #include <linux/acpi.h>
>  #include <linux/acpi_iort.h>
> +#include <linux/acpi_viot.h>
>  #include <linux/iommu.h>
>  #include <linux/signal.h>
>  #include <linux/kthread.h>
> @@ -1554,6 +1555,8 @@ static const struct iommu_ops
*acpi_iommu_configure_id(struct device *dev,
>                 return ops;
>
>         err = iort_iommu_configure_id(dev, id_in);
> +       if (err && err != -EPROBE_DEFER)
> +               err = viot_iommu_configure(dev);
>
>         /*
>          * If we have reason to believe the IOMMU driver missed the initial
> diff --git a/drivers/acpi/viot.c b/drivers/acpi/viot.c
> new file mode 100644
> index 000000000000..710e5a5eac70
> --- /dev/null
> +++ b/drivers/acpi/viot.c
> @@ -0,0 +1,350 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Virtual I/O topology
In the first place, more information on what this is all about, please.

What it does and how it is used.

Rafael J. Wysocki

2021-May-21 16:42 UTC

head link

[PATCH v2 2/6] ACPI: Move IOMMU setup code out of IORT

On Fri, Apr 23, 2021 at 1:57 PM Jean-Philippe Brucker
<jean-philippe at linaro.org> wrote:>
> Some of the IOMMU setup code in IORT is fairly generic and can be reused
> by VIOT. Extract it from IORT.
Except that iort_iommu_configure_id() is not really generic AFAICS.

Linux Virtualization - May 2021 - [PATCH v2 0/6] Add support for ACPI VIOT

[PATCH v2 0/6] Add support for ACPI VIOT

[PATCH v2 1/6] ACPI: arm64: Move DMA setup operations out of IORT

[PATCH v2 2/6] ACPI: Move IOMMU setup code out of IORT

[PATCH v2 3/6] ACPI: Add driver for the VIOT table

[PATCH v2 4/6] iommu/dma: Pass address limit rather than size to iommu_setup_dma_ops()

[PATCH v2 5/6] iommu/dma: Simplify calls to iommu_setup_dma_ops()

[PATCH v2 6/6] iommu/virtio: Enable x86 support

[PATCH v2 6/6] iommu/virtio: Enable x86 support

[PATCH v2 0/6] Add support for ACPI VIOT

[PATCH v2 0/6] Add support for ACPI VIOT

[PATCH v2 3/6] ACPI: Add driver for the VIOT table

[PATCH v2 2/6] ACPI: Move IOMMU setup code out of IORT