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Jason Gunthorpe

2023-Dec-07 18:03 UTC

[PATCH v2 0/7] IOMMU related FW parsing cleanup

These are the patches from the from the prior series without the "fwspec
polishing":
 https://lore.kernel.org/r/0-v2-36a0088ecaa7+22c6e-iommu_fwspec_jgg at
nvidia.com

Does a few things to prepare for the next:

- Clean up the call chains around dma_configure so the iommu_ops isn't being
  exposed.

- Add additional lockdep annotations now that we can.

- Fix some missed places that need to call tegra_dev_iommu_get_stream_id()

Based on Joerg's for-next with Robin's bus changes.

Robin's dma_base/size cleanup squashes the first patch, but we can't do
the ops removal in the other parts without it, so let's keep it
unsquashed.

v2:
 - Remove comments and bracket around tegra_dev_iommu_get_stream_id()
   in gp10b.c
 - Remove WARN_ON() in tegra186_mc_client_sid_override(), just return 0
 - Push the locking change to a later series
 - Drop the COMPILE_TEST improvement, not important enough to argue.
v1: https://lore.kernel.org/r/0-v1-720585788a7d+811b-iommu_fwspec_p1_jgg at
nvidia.com

Jason Gunthorpe (7):
  iommu: Remove struct iommu_ops *iommu from arch_setup_dma_ops()
  iommmu/of: Do not return struct iommu_ops from of_iommu_configure()
  iommu/of: Use -ENODEV consistently in of_iommu_configure()
  iommu: Mark dev_iommu_get() with lockdep
  iommu: Mark dev_iommu_priv_set() with a lockdep
  acpi: Do not return struct iommu_ops from acpi_iommu_configure_id()
  iommu/tegra: Use tegra_dev_iommu_get_stream_id() in the remaining
    places

 arch/arc/mm/dma.c                             |  2 +-
 arch/arm/mm/dma-mapping-nommu.c               |  2 +-
 arch/arm/mm/dma-mapping.c                     | 10 +--
 arch/arm64/mm/dma-mapping.c                   |  4 +-
 arch/mips/mm/dma-noncoherent.c                |  2 +-
 arch/riscv/mm/dma-noncoherent.c               |  2 +-
 drivers/acpi/scan.c                           | 32 ++++++----
 drivers/dma/tegra186-gpc-dma.c                |  8 +--
 .../gpu/drm/nouveau/nvkm/subdev/ltc/gp10b.c   |  9 +--
 drivers/hv/hv_common.c                        |  2 +-
 drivers/iommu/amd/iommu.c                     |  2 -
 drivers/iommu/apple-dart.c                    |  1 -
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c   |  1 -
 drivers/iommu/arm/arm-smmu/arm-smmu.c         |  1 -
 drivers/iommu/intel/iommu.c                   |  2 -
 drivers/iommu/iommu.c                         | 11 ++++
 drivers/iommu/of_iommu.c                      | 64 ++++++++-----------
 drivers/iommu/omap-iommu.c                    |  1 -
 drivers/memory/tegra/tegra186.c               | 14 ++--
 drivers/of/device.c                           | 24 ++++---
 include/linux/dma-map-ops.h                   |  4 +-
 include/linux/iommu.h                         |  5 +-
 include/linux/of_iommu.h                      | 13 ++--
 23 files changed, 105 insertions(+), 111 deletions(-)


base-commit: 173ff345925a394284250bfa6e47d231e62031c7
-- 
2.43.0

Jason Gunthorpe

2023-Dec-07 18:03 UTC

head link

[PATCH v2 1/7] iommu: Remove struct iommu_ops *iommu from arch_setup_dma_ops()

This is not being used to pass ops, it is just a way to tell if an
iommu driver was probed. These days this can be detected directly via
device_iommu_mapped(). Call device_iommu_mapped() in the two places that
need to check it and remove the iommu parameter everywhere.

Reviewed-by: Jerry Snitselaar <jsnitsel at redhat.com>
Reviewed-by: Lu Baolu <baolu.lu at linux.intel.com>
Reviewed-by: Moritz Fischer <mdf at kernel.org>
Acked-by: Christoph Hellwig <hch at lst.de>
Acked-by: Rob Herring <robh at kernel.org>
Tested-by: Hector Martin <marcan at marcan.st>
Signed-off-by: Jason Gunthorpe <jgg at nvidia.com>
---
 arch/arc/mm/dma.c               |  2 +-
 arch/arm/mm/dma-mapping-nommu.c |  2 +-
 arch/arm/mm/dma-mapping.c       | 10 +++++-----
 arch/arm64/mm/dma-mapping.c     |  4 ++--
 arch/mips/mm/dma-noncoherent.c  |  2 +-
 arch/riscv/mm/dma-noncoherent.c |  2 +-
 drivers/acpi/scan.c             |  3 +--
 drivers/hv/hv_common.c          |  2 +-
 drivers/of/device.c             |  2 +-
 include/linux/dma-map-ops.h     |  4 ++--
 10 files changed, 16 insertions(+), 17 deletions(-)

diff --git a/arch/arc/mm/dma.c b/arch/arc/mm/dma.c
index 2a7fbbb83b7056..197707bc765889 100644
--- a/arch/arc/mm/dma.c
+++ b/arch/arc/mm/dma.c
@@ -91,7 +91,7 @@ void arch_sync_dma_for_cpu(phys_addr_t paddr, size_t size,
  * Plug in direct dma map ops.
  */
 void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
-			const struct iommu_ops *iommu, bool coherent)
+			bool coherent)
 {
 	/*
 	 * IOC hardware snoops all DMA traffic keeping the caches consistent
diff --git a/arch/arm/mm/dma-mapping-nommu.c b/arch/arm/mm/dma-mapping-nommu.c
index cfd9c933d2f09c..b94850b579952a 100644
--- a/arch/arm/mm/dma-mapping-nommu.c
+++ b/arch/arm/mm/dma-mapping-nommu.c
@@ -34,7 +34,7 @@ void arch_sync_dma_for_cpu(phys_addr_t paddr, size_t size,
 }
 
 void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
-			const struct iommu_ops *iommu, bool coherent)
+			bool coherent)
 {
 	if (IS_ENABLED(CONFIG_CPU_V7M)) {
 		/*
diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c
index 5409225b4abc06..6c359a3af8d9c7 100644
--- a/arch/arm/mm/dma-mapping.c
+++ b/arch/arm/mm/dma-mapping.c
@@ -1713,7 +1713,7 @@ void arm_iommu_detach_device(struct device *dev)
 EXPORT_SYMBOL_GPL(arm_iommu_detach_device);
 
 static void arm_setup_iommu_dma_ops(struct device *dev, u64 dma_base, u64 size,
-				    const struct iommu_ops *iommu, bool coherent)
+				    bool coherent)
 {
 	struct dma_iommu_mapping *mapping;
 
@@ -1748,7 +1748,7 @@ static void arm_teardown_iommu_dma_ops(struct device *dev)
 #else
 
 static void arm_setup_iommu_dma_ops(struct device *dev, u64 dma_base, u64 size,
-				    const struct iommu_ops *iommu, bool coherent)
+				    bool coherent)
 {
 }
 
@@ -1757,7 +1757,7 @@ static void arm_teardown_iommu_dma_ops(struct device *dev)
{ }
 #endif	/* CONFIG_ARM_DMA_USE_IOMMU */
 
 void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
-			const struct iommu_ops *iommu, bool coherent)
+			bool coherent)
 {
 	/*
 	 * Due to legacy code that sets the ->dma_coherent flag from a bus
@@ -1776,8 +1776,8 @@ void arch_setup_dma_ops(struct device *dev, u64 dma_base,
u64 size,
 	if (dev->dma_ops)
 		return;
 
-	if (iommu)
-		arm_setup_iommu_dma_ops(dev, dma_base, size, iommu, coherent);
+	if (device_iommu_mapped(dev))
+		arm_setup_iommu_dma_ops(dev, dma_base, size, coherent);
 
 	xen_setup_dma_ops(dev);
 	dev->archdata.dma_ops_setup = true;
diff --git a/arch/arm64/mm/dma-mapping.c b/arch/arm64/mm/dma-mapping.c
index 3cb101e8cb29ba..61886e43e3a10f 100644
--- a/arch/arm64/mm/dma-mapping.c
+++ b/arch/arm64/mm/dma-mapping.c
@@ -47,7 +47,7 @@ void arch_teardown_dma_ops(struct device *dev)
 #endif
 
 void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
-			const struct iommu_ops *iommu, bool coherent)
+			bool coherent)
 {
 	int cls = cache_line_size_of_cpu();
 
@@ -58,7 +58,7 @@ void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64
size,
 		   ARCH_DMA_MINALIGN, cls);
 
 	dev->dma_coherent = coherent;
-	if (iommu)
+	if (device_iommu_mapped(dev))
 		iommu_setup_dma_ops(dev, dma_base, dma_base + size - 1);
 
 	xen_setup_dma_ops(dev);
diff --git a/arch/mips/mm/dma-noncoherent.c b/arch/mips/mm/dma-noncoherent.c
index 3c4fc97b9f394b..0f3cec663a12cd 100644
--- a/arch/mips/mm/dma-noncoherent.c
+++ b/arch/mips/mm/dma-noncoherent.c
@@ -138,7 +138,7 @@ void arch_sync_dma_for_cpu(phys_addr_t paddr, size_t size,
 
 #ifdef CONFIG_ARCH_HAS_SETUP_DMA_OPS
 void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
-		const struct iommu_ops *iommu, bool coherent)
+		bool coherent)
 {
 	dev->dma_coherent = coherent;
 }
diff --git a/arch/riscv/mm/dma-noncoherent.c b/arch/riscv/mm/dma-noncoherent.c
index 4e4e469b8dd66c..843107f834b231 100644
--- a/arch/riscv/mm/dma-noncoherent.c
+++ b/arch/riscv/mm/dma-noncoherent.c
@@ -129,7 +129,7 @@ void arch_dma_prep_coherent(struct page *page, size_t size)
 }
 
 void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
-		const struct iommu_ops *iommu, bool coherent)
+			bool coherent)
 {
 	WARN_TAINT(!coherent && riscv_cbom_block_size > ARCH_DMA_MINALIGN,
 		   TAINT_CPU_OUT_OF_SPEC,
diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index 02bb2cce423f47..444a0b3c72f2d8 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -1641,8 +1641,7 @@ int acpi_dma_configure_id(struct device *dev, enum
dev_dma_attr attr,
 	if (PTR_ERR(iommu) == -EPROBE_DEFER)
 		return -EPROBE_DEFER;
 
-	arch_setup_dma_ops(dev, 0, U64_MAX,
-				iommu, attr == DEV_DMA_COHERENT);
+	arch_setup_dma_ops(dev, 0, U64_MAX, attr == DEV_DMA_COHERENT);
 
 	return 0;
 }
diff --git a/drivers/hv/hv_common.c b/drivers/hv/hv_common.c
index 4372f5d146ab22..0285a74363b3d1 100644
--- a/drivers/hv/hv_common.c
+++ b/drivers/hv/hv_common.c
@@ -488,7 +488,7 @@ void hv_setup_dma_ops(struct device *dev, bool coherent)
 	 * Hyper-V does not offer a vIOMMU in the guest
 	 * VM, so pass 0/NULL for the IOMMU settings
 	 */
-	arch_setup_dma_ops(dev, 0, 0, NULL, coherent);
+	arch_setup_dma_ops(dev, 0, 0, coherent);
 }
 EXPORT_SYMBOL_GPL(hv_setup_dma_ops);
 
diff --git a/drivers/of/device.c b/drivers/of/device.c
index 1ca42ad9dd159d..65c71be71a8d45 100644
--- a/drivers/of/device.c
+++ b/drivers/of/device.c
@@ -193,7 +193,7 @@ int of_dma_configure_id(struct device *dev, struct
device_node *np,
 	dev_dbg(dev, "device is%sbehind an iommu\n",
 		iommu ? " " : " not ");
 
-	arch_setup_dma_ops(dev, dma_start, size, iommu, coherent);
+	arch_setup_dma_ops(dev, dma_start, size, coherent);
 
 	if (!iommu)
 		of_dma_set_restricted_buffer(dev, np);
diff --git a/include/linux/dma-map-ops.h b/include/linux/dma-map-ops.h
index a52e508d1869f6..e9cc317e9d7de6 100644
--- a/include/linux/dma-map-ops.h
+++ b/include/linux/dma-map-ops.h
@@ -427,10 +427,10 @@ bool arch_dma_unmap_sg_direct(struct device *dev, struct
scatterlist *sg,
 
 #ifdef CONFIG_ARCH_HAS_SETUP_DMA_OPS
 void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
-		const struct iommu_ops *iommu, bool coherent);
+		bool coherent);
 #else
 static inline void arch_setup_dma_ops(struct device *dev, u64 dma_base,
-		u64 size, const struct iommu_ops *iommu, bool coherent)
+		u64 size, bool coherent)
 {
 }
 #endif /* CONFIG_ARCH_HAS_SETUP_DMA_OPS */
-- 
2.43.0

Jason Gunthorpe

2023-Dec-07 18:03 UTC

head link

[PATCH v2 2/7] iommmu/of: Do not return struct iommu_ops from of_iommu_configure()

Nothing needs this pointer. Return a normal error code with the usual
IOMMU semantic that ENODEV means 'there is no IOMMU driver'.

Reviewed-by: Jerry Snitselaar <jsnitsel at redhat.com>
Reviewed-by: Lu Baolu <baolu.lu at linux.intel.com>
Acked-by: Rob Herring <robh at kernel.org>
Tested-by: Hector Martin <marcan at marcan.st>
Signed-off-by: Jason Gunthorpe <jgg at nvidia.com>
---
 drivers/iommu/of_iommu.c | 31 +++++++++++++++++++------------
 drivers/of/device.c      | 22 +++++++++++++++-------
 include/linux/of_iommu.h | 13 ++++++-------
 3 files changed, 40 insertions(+), 26 deletions(-)

diff --git a/drivers/iommu/of_iommu.c b/drivers/iommu/of_iommu.c
index 5ecca53847d325..c6510d7e7b241b 100644
--- a/drivers/iommu/of_iommu.c
+++ b/drivers/iommu/of_iommu.c
@@ -107,16 +107,22 @@ static int of_iommu_configure_device(struct device_node
*master_np,
 		      of_iommu_configure_dev(master_np, dev);
 }
 
-const struct iommu_ops *of_iommu_configure(struct device *dev,
-					   struct device_node *master_np,
-					   const u32 *id)
+/*
+ * Returns:
+ *  0 on success, an iommu was configured
+ *  -ENODEV if the device does not have any IOMMU
+ *  -EPROBEDEFER if probing should be tried again
+ *  -errno fatal errors
+ */
+int of_iommu_configure(struct device *dev, struct device_node *master_np,
+		       const u32 *id)
 {
 	const struct iommu_ops *ops = NULL;
 	struct iommu_fwspec *fwspec;
 	int err = NO_IOMMU;
 
 	if (!master_np)
-		return NULL;
+		return -ENODEV;
 
 	/* Serialise to make dev->iommu stable under our potential fwspec */
 	mutex_lock(&iommu_probe_device_lock);
@@ -124,7 +130,7 @@ const struct iommu_ops *of_iommu_configure(struct device
*dev,
 	if (fwspec) {
 		if (fwspec->ops) {
 			mutex_unlock(&iommu_probe_device_lock);
-			return fwspec->ops;
+			return 0;
 		}
 		/* In the deferred case, start again from scratch */
 		iommu_fwspec_free(dev);
@@ -169,14 +175,15 @@ const struct iommu_ops *of_iommu_configure(struct device
*dev,
 		err = iommu_probe_device(dev);
 
 	/* Ignore all other errors apart from EPROBE_DEFER */
-	if (err == -EPROBE_DEFER) {
-		ops = ERR_PTR(err);
-	} else if (err < 0) {
-		dev_dbg(dev, "Adding to IOMMU failed: %d\n", err);
-		ops = NULL;
+	if (err < 0) {
+		if (err == -EPROBE_DEFER)
+			return err;
+		dev_dbg(dev, "Adding to IOMMU failed: %pe\n", ERR_PTR(err));
+		return err;
 	}
-
-	return ops;
+	if (!ops)
+		return -ENODEV;
+	return 0;
 }
 
 static enum iommu_resv_type __maybe_unused
diff --git a/drivers/of/device.c b/drivers/of/device.c
index 65c71be71a8d45..873d933e8e6d1d 100644
--- a/drivers/of/device.c
+++ b/drivers/of/device.c
@@ -93,12 +93,12 @@ of_dma_set_restricted_buffer(struct device *dev, struct
device_node *np)
 int of_dma_configure_id(struct device *dev, struct device_node *np,
 			bool force_dma, const u32 *id)
 {
-	const struct iommu_ops *iommu;
 	const struct bus_dma_region *map = NULL;
 	struct device_node *bus_np;
 	u64 dma_start = 0;
 	u64 mask, end, size = 0;
 	bool coherent;
+	int iommu_ret;
 	int ret;
 
 	if (np == dev->of_node)
@@ -181,21 +181,29 @@ int of_dma_configure_id(struct device *dev, struct
device_node *np,
 	dev_dbg(dev, "device is%sdma coherent\n",
 		coherent ? " " : " not ");
 
-	iommu = of_iommu_configure(dev, np, id);
-	if (PTR_ERR(iommu) == -EPROBE_DEFER) {
+	iommu_ret = of_iommu_configure(dev, np, id);
+	if (iommu_ret == -EPROBE_DEFER) {
 		/* Don't touch range map if it wasn't set from a valid dma-ranges */
 		if (!ret)
 			dev->dma_range_map = NULL;
 		kfree(map);
 		return -EPROBE_DEFER;
-	}
+	} else if (iommu_ret == -ENODEV) {
+		dev_dbg(dev, "device is not behind an iommu\n");
+	} else if (iommu_ret) {
+		dev_err(dev, "iommu configuration for device failed with %pe\n",
+			ERR_PTR(iommu_ret));
 
-	dev_dbg(dev, "device is%sbehind an iommu\n",
-		iommu ? " " : " not ");
+		/*
+		 * Historically this routine doesn't fail driver probing
+		 * due to errors in of_iommu_configure()
+		 */
+	} else
+		dev_dbg(dev, "device is behind an iommu\n");
 
 	arch_setup_dma_ops(dev, dma_start, size, coherent);
 
-	if (!iommu)
+	if (iommu_ret)
 		of_dma_set_restricted_buffer(dev, np);
 
 	return 0;
diff --git a/include/linux/of_iommu.h b/include/linux/of_iommu.h
index 9a5e6b410dd2fb..e61cbbe12dac6f 100644
--- a/include/linux/of_iommu.h
+++ b/include/linux/of_iommu.h
@@ -8,20 +8,19 @@ struct iommu_ops;
 
 #ifdef CONFIG_OF_IOMMU
 
-extern const struct iommu_ops *of_iommu_configure(struct device *dev,
-					struct device_node *master_np,
-					const u32 *id);
+extern int of_iommu_configure(struct device *dev, struct device_node
*master_np,
+			      const u32 *id);
 
 extern void of_iommu_get_resv_regions(struct device *dev,
 				      struct list_head *list);
 
 #else
 
-static inline const struct iommu_ops *of_iommu_configure(struct device *dev,
-					 struct device_node *master_np,
-					 const u32 *id)
+static inline int of_iommu_configure(struct device *dev,
+				     struct device_node *master_np,
+				     const u32 *id)
 {
-	return NULL;
+	return -ENODEV;
 }
 
 static inline void of_iommu_get_resv_regions(struct device *dev,
-- 
2.43.0

Jason Gunthorpe

2023-Dec-07 18:03 UTC

head link

[PATCH v2 3/7] iommu/of: Use -ENODEV consistently in of_iommu_configure()

Instead of returning 1 and trying to handle positive error codes just
stick to the convention of returning -ENODEV. Remove references to ops
from of_iommu_configure(), a NULL ops will already generate an error code.

There is no reason to check dev->bus, if err=0 at this point then the
called configure functions thought there was an iommu and we should try to
probe it. Remove it.

Reviewed-by: Jerry Snitselaar <jsnitsel at redhat.com>
Reviewed-by: Moritz Fischer <moritzf at google.com>
Tested-by: Hector Martin <marcan at marcan.st>
Signed-off-by: Jason Gunthorpe <jgg at nvidia.com>
---
 drivers/iommu/of_iommu.c | 49 ++++++++++++----------------------------
 1 file changed, 15 insertions(+), 34 deletions(-)

diff --git a/drivers/iommu/of_iommu.c b/drivers/iommu/of_iommu.c
index c6510d7e7b241b..164317bfb8a81f 100644
--- a/drivers/iommu/of_iommu.c
+++ b/drivers/iommu/of_iommu.c
@@ -17,8 +17,6 @@
 #include <linux/slab.h>
 #include <linux/fsl/mc.h>
 
-#define NO_IOMMU	1
-
 static int of_iommu_xlate(struct device *dev,
 			  struct of_phandle_args *iommu_spec)
 {
@@ -29,7 +27,7 @@ static int of_iommu_xlate(struct device *dev,
 	ops = iommu_ops_from_fwnode(fwnode);
 	if ((ops && !ops->of_xlate) ||
 	    !of_device_is_available(iommu_spec->np))
-		return NO_IOMMU;
+		return -ENODEV;
 
 	ret = iommu_fwspec_init(dev, &iommu_spec->np->fwnode, ops);
 	if (ret)
@@ -61,7 +59,7 @@ static int of_iommu_configure_dev_id(struct device_node
*master_np,
 			 "iommu-map-mask", &iommu_spec.np,
 			 iommu_spec.args);
 	if (err)
-		return err == -ENODEV ? NO_IOMMU : err;
+		return err;
 
 	err = of_iommu_xlate(dev, &iommu_spec);
 	of_node_put(iommu_spec.np);
@@ -72,7 +70,7 @@ static int of_iommu_configure_dev(struct device_node
*master_np,
 				  struct device *dev)
 {
 	struct of_phandle_args iommu_spec;
-	int err = NO_IOMMU, idx = 0;
+	int err = -ENODEV, idx = 0;
 
 	while (!of_parse_phandle_with_args(master_np, "iommus",
 					   "#iommu-cells",
@@ -117,9 +115,8 @@ static int of_iommu_configure_device(struct device_node
*master_np,
 int of_iommu_configure(struct device *dev, struct device_node *master_np,
 		       const u32 *id)
 {
-	const struct iommu_ops *ops = NULL;
 	struct iommu_fwspec *fwspec;
-	int err = NO_IOMMU;
+	int err;
 
 	if (!master_np)
 		return -ENODEV;
@@ -153,37 +150,21 @@ int of_iommu_configure(struct device *dev, struct
device_node *master_np,
 	} else {
 		err = of_iommu_configure_device(master_np, dev, id);
 	}
-
-	/*
-	 * Two success conditions can be represented by non-negative err here:
-	 * >0 : there is no IOMMU, or one was unavailable for non-fatal reasons
-	 *  0 : we found an IOMMU, and dev->fwspec is initialised appropriately
-	 * <0 : any actual error
-	 */
-	if (!err) {
-		/* The fwspec pointer changed, read it again */
-		fwspec = dev_iommu_fwspec_get(dev);
-		ops    = fwspec->ops;
-	}
 	mutex_unlock(&iommu_probe_device_lock);
 
-	/*
-	 * If we have reason to believe the IOMMU driver missed the initial
-	 * probe for dev, replay it to get things in order.
-	 */
-	if (!err && dev->bus)
-		err = iommu_probe_device(dev);
-
-	/* Ignore all other errors apart from EPROBE_DEFER */
-	if (err < 0) {
-		if (err == -EPROBE_DEFER)
-			return err;
-		dev_dbg(dev, "Adding to IOMMU failed: %pe\n", ERR_PTR(err));
+	if (err == -ENODEV || err == -EPROBE_DEFER)
 		return err;
-	}
-	if (!ops)
-		return -ENODEV;
+	if (err)
+		goto err_log;
+
+	err = iommu_probe_device(dev);
+	if (err)
+		goto err_log;
 	return 0;
+
+err_log:
+	dev_dbg(dev, "Adding to IOMMU failed: %pe\n", ERR_PTR(err));
+	return err;
 }
 
 static enum iommu_resv_type __maybe_unused
-- 
2.43.0

Jason Gunthorpe

2023-Dec-07 18:03 UTC

head link

[PATCH v2 4/7] iommu: Mark dev_iommu_get() with lockdep

Allocation of dev->iommu must be done under the
iommu_probe_device_lock. Mark this with lockdep to discourage future
mistakes.

Reviewed-by: Jerry Snitselaar <jsnitsel at redhat.com>
Tested-by: Hector Martin <marcan at marcan.st>
Reviewed-by: Lu Baolu <baolu.lu at linux.intel.com>
Reviewed-by: Moritz Fischer <moritzf at google.com>
Signed-off-by: Jason Gunthorpe <jgg at nvidia.com>
---
 drivers/iommu/iommu.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index 0d25468d53a68a..4323b6276e977f 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -334,6 +334,8 @@ static struct dev_iommu *dev_iommu_get(struct device *dev)
 {
 	struct dev_iommu *param = dev->iommu;
 
+	lockdep_assert_held(&iommu_probe_device_lock);
+
 	if (param)
 		return param;
 
-- 
2.43.0

Jason Gunthorpe

2023-Dec-07 18:03 UTC

head link

[PATCH v2 5/7] iommu: Mark dev_iommu_priv_set() with a lockdep

A perfect driver would only call dev_iommu_priv_set() from its probe
callback. We've made it functionally correct to call it from the of_xlate
by adding a lock around that call.

lockdep assert that iommu_probe_device_lock is held to discourage misuse.

Exclude PPC kernels with CONFIG_FSL_PAMU turned on because FSL_PAMU uses a
global static for its priv and abuses priv for its domain.

Remove the pointless stores of NULL, all these are on paths where the core
code will free dev->iommu after the op returns.

Reviewed-by: Lu Baolu <baolu.lu at linux.intel.com>
Reviewed-by: Jerry Snitselaar <jsnitsel at redhat.com>
Tested-by: Hector Martin <marcan at marcan.st>
Signed-off-by: Jason Gunthorpe <jgg at nvidia.com>
---
 drivers/iommu/amd/iommu.c                   | 2 --
 drivers/iommu/apple-dart.c                  | 1 -
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 1 -
 drivers/iommu/arm/arm-smmu/arm-smmu.c       | 1 -
 drivers/iommu/intel/iommu.c                 | 2 --
 drivers/iommu/iommu.c                       | 9 +++++++++
 drivers/iommu/omap-iommu.c                  | 1 -
 include/linux/iommu.h                       | 5 +----
 8 files changed, 10 insertions(+), 12 deletions(-)

diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c
index 9f706436082833..be58644a6fa518 100644
--- a/drivers/iommu/amd/iommu.c
+++ b/drivers/iommu/amd/iommu.c
@@ -551,8 +551,6 @@ static void amd_iommu_uninit_device(struct device *dev)
 	if (dev_data->domain)
 		detach_device(dev);
 
-	dev_iommu_priv_set(dev, NULL);
-
 	/*
 	 * We keep dev_data around for unplugged devices and reuse it when the
 	 * device is re-plugged - not doing so would introduce a ton of races.
diff --git a/drivers/iommu/apple-dart.c b/drivers/iommu/apple-dart.c
index 7438e9c82ba982..25135440b5dd54 100644
--- a/drivers/iommu/apple-dart.c
+++ b/drivers/iommu/apple-dart.c
@@ -743,7 +743,6 @@ static void apple_dart_release_device(struct device *dev)
 {
 	struct apple_dart_master_cfg *cfg = dev_iommu_priv_get(dev);
 
-	dev_iommu_priv_set(dev, NULL);
 	kfree(cfg);
 }
 
diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
index fc4317c25b6d53..1855d3892b15f8 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
@@ -2695,7 +2695,6 @@ static struct iommu_device *arm_smmu_probe_device(struct
device *dev)
 
 err_free_master:
 	kfree(master);
-	dev_iommu_priv_set(dev, NULL);
 	return ERR_PTR(ret);
 }
 
diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu.c
b/drivers/iommu/arm/arm-smmu/arm-smmu.c
index 4d09c004789274..adc7937fd8a3a3 100644
--- a/drivers/iommu/arm/arm-smmu/arm-smmu.c
+++ b/drivers/iommu/arm/arm-smmu/arm-smmu.c
@@ -1420,7 +1420,6 @@ static void arm_smmu_release_device(struct device *dev)
 
 	arm_smmu_rpm_put(cfg->smmu);
 
-	dev_iommu_priv_set(dev, NULL);
 	kfree(cfg);
 }
 
diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index 897159dba47de4..511589341074f0 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -4461,7 +4461,6 @@ static struct iommu_device
*intel_iommu_probe_device(struct device *dev)
 		ret = intel_pasid_alloc_table(dev);
 		if (ret) {
 			dev_err(dev, "PASID table allocation failed\n");
-			dev_iommu_priv_set(dev, NULL);
 			kfree(info);
 			return ERR_PTR(ret);
 		}
@@ -4479,7 +4478,6 @@ static void intel_iommu_release_device(struct device *dev)
 	dmar_remove_one_dev_info(dev);
 	intel_pasid_free_table(dev);
 	intel_iommu_debugfs_remove_dev(info);
-	dev_iommu_priv_set(dev, NULL);
 	kfree(info);
 	set_dma_ops(dev, NULL);
 }
diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index 4323b6276e977f..08f29a1dfcd5f8 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -387,6 +387,15 @@ static u32 dev_iommu_get_max_pasids(struct device *dev)
 	return min_t(u32, max_pasids, dev->iommu->iommu_dev->max_pasids);
 }
 
+void dev_iommu_priv_set(struct device *dev, void *priv)
+{
+	/* FSL_PAMU does something weird */
+	if (!IS_ENABLED(CONFIG_FSL_PAMU))
+		lockdep_assert_held(&iommu_probe_device_lock);
+	dev->iommu->priv = priv;
+}
+EXPORT_SYMBOL_GPL(dev_iommu_priv_set);
+
 /*
  * Init the dev->iommu and dev->iommu_group in the struct device and get
the
  * driver probed
diff --git a/drivers/iommu/omap-iommu.c b/drivers/iommu/omap-iommu.c
index c66b070841dd41..c9528065a59afa 100644
--- a/drivers/iommu/omap-iommu.c
+++ b/drivers/iommu/omap-iommu.c
@@ -1719,7 +1719,6 @@ static void omap_iommu_release_device(struct device *dev)
 	if (!dev->of_node || !arch_data)
 		return;
 
-	dev_iommu_priv_set(dev, NULL);
 	kfree(arch_data);
 
 }
diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index c7394b39599c84..c24933a1d0d643 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -840,10 +840,7 @@ static inline void *dev_iommu_priv_get(struct device *dev)
 		return NULL;
 }
 
-static inline void dev_iommu_priv_set(struct device *dev, void *priv)
-{
-	dev->iommu->priv = priv;
-}
+void dev_iommu_priv_set(struct device *dev, void *priv);
 
 extern struct mutex iommu_probe_device_lock;
 int iommu_probe_device(struct device *dev);
-- 
2.43.0

Jason Gunthorpe

2023-Dec-07 18:03 UTC

head link

[PATCH v2 6/7] acpi: Do not return struct iommu_ops from acpi_iommu_configure_id()

Nothing needs this pointer. Return a normal error code with the usual
IOMMU semantic that ENODEV means 'there is no IOMMU driver'.

Acked-by: Rafael J. Wysocki <rafael.j.wysocki at intel.com>
Reviewed-by: Jerry Snitselaar <jsnitsel at redhat.com>
Reviewed-by: Lu Baolu <baolu.lu at linux.intel.com>
Reviewed-by: Moritz Fischer <moritzf at google.com>
Tested-by: Hector Martin <marcan at marcan.st>
Signed-off-by: Jason Gunthorpe <jgg at nvidia.com>
---
 drivers/acpi/scan.c | 29 +++++++++++++++++------------
 1 file changed, 17 insertions(+), 12 deletions(-)

diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index 444a0b3c72f2d8..340ba720c72129 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -1562,8 +1562,7 @@ static inline const struct iommu_ops
*acpi_iommu_fwspec_ops(struct device *dev)
 	return fwspec ? fwspec->ops : NULL;
 }
 
-static const struct iommu_ops *acpi_iommu_configure_id(struct device *dev,
-						       const u32 *id_in)
+static int acpi_iommu_configure_id(struct device *dev, const u32 *id_in)
 {
 	int err;
 	const struct iommu_ops *ops;
@@ -1577,7 +1576,7 @@ static const struct iommu_ops
*acpi_iommu_configure_id(struct device *dev,
 	ops = acpi_iommu_fwspec_ops(dev);
 	if (ops) {
 		mutex_unlock(&iommu_probe_device_lock);
-		return ops;
+		return 0;
 	}
 
 	err = iort_iommu_configure_id(dev, id_in);
@@ -1594,12 +1593,14 @@ static const struct iommu_ops
*acpi_iommu_configure_id(struct device *dev,
 
 	/* Ignore all other errors apart from EPROBE_DEFER */
 	if (err == -EPROBE_DEFER) {
-		return ERR_PTR(err);
+		return err;
 	} else if (err) {
 		dev_dbg(dev, "Adding to IOMMU failed: %d\n", err);
-		return NULL;
+		return -ENODEV;
 	}
-	return acpi_iommu_fwspec_ops(dev);
+	if (!acpi_iommu_fwspec_ops(dev))
+		return -ENODEV;
+	return 0;
 }
 
 #else /* !CONFIG_IOMMU_API */
@@ -1611,10 +1612,9 @@ int acpi_iommu_fwspec_init(struct device *dev, u32 id,
 	return -ENODEV;
 }
 
-static const struct iommu_ops *acpi_iommu_configure_id(struct device *dev,
-						       const u32 *id_in)
+static int acpi_iommu_configure_id(struct device *dev, const u32 *id_in)
 {
-	return NULL;
+	return -ENODEV;
 }
 
 #endif /* !CONFIG_IOMMU_API */
@@ -1628,7 +1628,7 @@ static const struct iommu_ops
*acpi_iommu_configure_id(struct device *dev,
 int acpi_dma_configure_id(struct device *dev, enum dev_dma_attr attr,
 			  const u32 *input_id)
 {
-	const struct iommu_ops *iommu;
+	int ret;
 
 	if (attr == DEV_DMA_NOT_SUPPORTED) {
 		set_dma_ops(dev, &dma_dummy_ops);
@@ -1637,10 +1637,15 @@ int acpi_dma_configure_id(struct device *dev, enum
dev_dma_attr attr,
 
 	acpi_arch_dma_setup(dev);
 
-	iommu = acpi_iommu_configure_id(dev, input_id);
-	if (PTR_ERR(iommu) == -EPROBE_DEFER)
+	ret = acpi_iommu_configure_id(dev, input_id);
+	if (ret == -EPROBE_DEFER)
 		return -EPROBE_DEFER;
 
+	/*
+	 * Historically this routine doesn't fail driver probing due to errors
+	 * in acpi_iommu_configure_id()
+	 */
+
 	arch_setup_dma_ops(dev, 0, U64_MAX, attr == DEV_DMA_COHERENT);
 
 	return 0;
-- 
2.43.0

Jason Gunthorpe

2023-Dec-07 18:03 UTC

head link

[PATCH v2 7/7] iommu/tegra: Use tegra_dev_iommu_get_stream_id() in the remaining places

This API was defined to formalize the access to internal iommu details on
some Tegra SOCs, but a few callers got missed. Add them.

The helper already masks by 0xFFFF so remove this code from the callers.

Suggested-by: Thierry Reding <thierry.reding at gmail.com>
Reviewed-by: Thierry Reding <treding at nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg at nvidia.com>
---
 drivers/dma/tegra186-gpc-dma.c                  |  8 +++-----
 drivers/gpu/drm/nouveau/nvkm/subdev/ltc/gp10b.c |  9 ++-------
 drivers/memory/tegra/tegra186.c                 | 14 ++++++++------
 3 files changed, 13 insertions(+), 18 deletions(-)

diff --git a/drivers/dma/tegra186-gpc-dma.c b/drivers/dma/tegra186-gpc-dma.c
index fa4d4142a68a21..88547a23825b18 100644
--- a/drivers/dma/tegra186-gpc-dma.c
+++ b/drivers/dma/tegra186-gpc-dma.c
@@ -1348,8 +1348,8 @@ static int tegra_dma_program_sid(struct tegra_dma_channel
*tdc, int stream_id)
 static int tegra_dma_probe(struct platform_device *pdev)
 {
 	const struct tegra_dma_chip_data *cdata = NULL;
-	struct iommu_fwspec *iommu_spec;
-	unsigned int stream_id, i;
+	unsigned int i;
+	u32 stream_id;
 	struct tegra_dma *tdma;
 	int ret;
 
@@ -1378,12 +1378,10 @@ static int tegra_dma_probe(struct platform_device *pdev)
 
 	tdma->dma_dev.dev = &pdev->dev;
 
-	iommu_spec = dev_iommu_fwspec_get(&pdev->dev);
-	if (!iommu_spec) {
+	if (!tegra_dev_iommu_get_stream_id(&pdev->dev, &stream_id)) {
 		dev_err(&pdev->dev, "Missing iommu stream-id\n");
 		return -EINVAL;
 	}
-	stream_id = iommu_spec->ids[0] & 0xffff;
 
 	ret = device_property_read_u32(&pdev->dev,
"dma-channel-mask",
 				       &tdma->chan_mask);
diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/ltc/gp10b.c
b/drivers/gpu/drm/nouveau/nvkm/subdev/ltc/gp10b.c
index e7e8fdf3adab7a..29682722b0b36b 100644
--- a/drivers/gpu/drm/nouveau/nvkm/subdev/ltc/gp10b.c
+++ b/drivers/gpu/drm/nouveau/nvkm/subdev/ltc/gp10b.c
@@ -28,19 +28,14 @@ static void
 gp10b_ltc_init(struct nvkm_ltc *ltc)
 {
 	struct nvkm_device *device = ltc->subdev.device;
-	struct iommu_fwspec *spec;
+	u32 sid;
 
 	nvkm_wr32(device, 0x17e27c, ltc->ltc_nr);
 	nvkm_wr32(device, 0x17e000, ltc->ltc_nr);
 	nvkm_wr32(device, 0x100800, ltc->ltc_nr);
 
-	spec = dev_iommu_fwspec_get(device->dev);
-	if (spec) {
-		u32 sid = spec->ids[0] & 0xffff;
-
-		/* stream ID */
+	if (tegra_dev_iommu_get_stream_id(device->dev, &sid))
 		nvkm_wr32(device, 0x160000, sid << 2);
-	}
 }
 
 static const struct nvkm_ltc_func
diff --git a/drivers/memory/tegra/tegra186.c b/drivers/memory/tegra/tegra186.c
index 533f85a4b2bdb7..9cbf22a10a8270 100644
--- a/drivers/memory/tegra/tegra186.c
+++ b/drivers/memory/tegra/tegra186.c
@@ -111,9 +111,12 @@ static void tegra186_mc_client_sid_override(struct tegra_mc
*mc,
 static int tegra186_mc_probe_device(struct tegra_mc *mc, struct device *dev)
 {
 #if IS_ENABLED(CONFIG_IOMMU_API)
-	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
 	struct of_phandle_args args;
 	unsigned int i, index = 0;
+	u32 sid;
+
+	if (!tegra_dev_iommu_get_stream_id(dev, &sid))
+		return 0;
 
 	while (!of_parse_phandle_with_args(dev->of_node, "interconnects",
"#interconnect-cells",
 					   index, &args)) {
@@ -121,11 +124,10 @@ static int tegra186_mc_probe_device(struct tegra_mc *mc,
struct device *dev)
 			for (i = 0; i < mc->soc->num_clients; i++) {
 				const struct tegra_mc_client *client = &mc->soc->clients[i];
 
-				if (client->id == args.args[0]) {
-					u32 sid = fwspec->ids[0] & MC_SID_STREAMID_OVERRIDE_MASK;
-
-					tegra186_mc_client_sid_override(mc, client, sid);
-				}
+				if (client->id == args.args[0])
+					tegra186_mc_client_sid_override(
+						mc, client,
+						sid & MC_SID_STREAMID_OVERRIDE_MASK);
 			}
 		}
 
-- 
2.43.0

Joerg Roedel

2023-Dec-12 09:19 UTC

head link

[PATCH v2 0/7] IOMMU related FW parsing cleanup

On Thu, Dec 07, 2023 at 02:03:07PM -0400, Jason Gunthorpe
wrote:> Jason Gunthorpe (7):
>   iommu: Remove struct iommu_ops *iommu from arch_setup_dma_ops()
>   iommmu/of: Do not return struct iommu_ops from of_iommu_configure()
>   iommu/of: Use -ENODEV consistently in of_iommu_configure()
>   iommu: Mark dev_iommu_get() with lockdep
>   iommu: Mark dev_iommu_priv_set() with a lockdep
>   acpi: Do not return struct iommu_ops from acpi_iommu_configure_id()
>   iommu/tegra: Use tegra_dev_iommu_get_stream_id() in the remaining
>     places
Applied, thanks.

Nouveau - Dec 2023 - [PATCH v2 2/7] iommmu/of: Do not return struct iommu_ops from of_iommu_configure()

[PATCH v2 0/7] IOMMU related FW parsing cleanup

[PATCH v2 1/7] iommu: Remove struct iommu_ops *iommu from arch_setup_dma_ops()

[PATCH v2 2/7] iommmu/of: Do not return struct iommu_ops from of_iommu_configure()

[PATCH v2 3/7] iommu/of: Use -ENODEV consistently in of_iommu_configure()

[PATCH v2 4/7] iommu: Mark dev_iommu_get() with lockdep

[PATCH v2 5/7] iommu: Mark dev_iommu_priv_set() with a lockdep

[PATCH v2 6/7] acpi: Do not return struct iommu_ops from acpi_iommu_configure_id()

[PATCH v2 7/7] iommu/tegra: Use tegra_dev_iommu_get_stream_id() in the remaining places

[PATCH v2 0/7] IOMMU related FW parsing cleanup