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dma-mapping: Simplify arch_setup_dma_ops()

PATCH Superseded Robin Murphy 4 participants 13 messages Dec 13, 2023 – Dec 17, 2023

Subsystems (17)
Arm (32-bit) ACPI MIPS RISC-V +13 more subsystems

v2 of 4 Superseded Latest is v4 →

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Robin Murphy

author maintainer
#0 lore raw

v2 cover dma-mapping: Simplify arch_setup_dma_ops()

v1: https://lore.kernel.org/linux-iommu/[email protected]/

Hi all,

Here's v2 with a few tweaks and fixes to address review comments, a couple of major issues fixed in the last two patches that I really should have spotted initially, plus a bit more code deletion that I realised could fit in this step. I've left it tagged as a dma-mapping series since spiritually it still is, but it looks like it will want to go via the IOMMU tree.

Thanks,
Robin.

Robin Murphy (7):
OF: Retire dma-ranges mask workaround
OF: Simplify DMA range calculations ACPI/IORT: Handle memory address size limits as limits
dma-mapping: Add helpers for dma_range_map bounds iommu/dma: Make limit checks self-contained iommu/dma: Centralise iommu_setup_dma_ops()
dma-mapping: Simplify arch_setup_dma_ops()

 arch/arc/mm/dma.c               |  3 +--
 arch/arm/mm/dma-mapping-nommu.c |  3 +--
 arch/arm/mm/dma-mapping.c       | 18 +++++++-------
 arch/arm64/mm/dma-mapping.c     |  5 +---
 arch/loongarch/kernel/dma.c     |  9 ++-----
 arch/mips/mm/dma-noncoherent.c  |  3 +--
 arch/riscv/mm/dma-noncoherent.c |  3 +--
 drivers/acpi/arm64/dma.c        | 17 ++++---------
 drivers/acpi/arm64/iort.c       | 20 ++++++++--------
 drivers/acpi/scan.c             |  3 +--
 drivers/hv/hv_common.c          |  6 +----
 drivers/iommu/amd/iommu.c       |  8 -------
 drivers/iommu/dma-iommu.c       | 39 ++++++++++++------------------
 drivers/iommu/dma-iommu.h       | 14 +++++------
 drivers/iommu/intel/iommu.c     |  7 ------
 drivers/iommu/iommu.c           |  6 ++---
 drivers/iommu/s390-iommu.c      |  6 -----
 drivers/iommu/virtio-iommu.c    | 10 --------
 drivers/of/device.c             | 42 ++++++---------------------------
 include/linux/acpi_iort.h       |  4 ++--
 include/linux/dma-direct.h      | 18 ++++++++++++++
 include/linux/dma-map-ops.h     |  6 ++---
 include/linux/iommu.h           |  7 ------
 23 files changed, 86 insertions(+), 171 deletions(-)
Signature · 1 line
2.39.2.101.g768bb238c484.dirty
author maintainer
#1 lore raw

PATCH v2 1/7 OF: Retire dma-ranges mask workaround

The fixup adding 1 to the dma-ranges size may have been for the benefit of some early AMD Seattle DTs, or may have merely been a just-in-case, but either way anyone who might have deserved to get the message has hopefully seen the warning in the 9 years we've had it there. The modern dma_range_map mechanism should happily handle odd-sized ranges with no ill effect, so there's little need to care anyway now. Clean it up.

Acked-by Rob Herring <[email protected]>
Signed-off-by Robin Murphy <[email protected]>

---
v2: Tweak commit message

---
 drivers/of/device.c | 16 ----------------
 1 file changed, 16 deletions(-)
drivers/of/device.c +0 -16
index 1ca42ad9dd15..526a42cdf66e 100644
@@ -129,22 +129,6 @@ int of_dma_configure_id(struct device *dev, struct device_node *np,
 				dma_end = r->dma_start + r->size;
 		}
 		size = dma_end - dma_start;
-
-		/*
-		 * Add a work around to treat the size as mask + 1 in case
-		 * it is defined in DT as a mask.
-		 */
-		if (size & 1) {
-			dev_warn(dev, "Invalid size 0x%llx for dma-range(s)\n",
-				 size);
-			size = size + 1;
-		}
-
-		if (!size) {
-			dev_err(dev, "Adjusted size 0x%llx invalid\n", size);
-			kfree(map);
-			return -EINVAL;
-		}
 	}
 
 	/*
Signature · 1 line
2.39.2.101.g768bb238c484.dirty
author maintainer
#2 lore raw

PATCH v2 2/7 OF: Simplify DMA range calculations

In reply to Robin Murphy

Juggling start, end, and size values for a range is somewhat redundant and a little hard to follow. Consolidate down to just using inclusive start and end, which saves us worrying about size overflows for full 64-bit ranges (note that passing a potentially-overflowed value through to arch_setup_dma_ops() is benign for all current implementations, and this is working towards removing that anyway).

Acked-by Rob Herring <[email protected]>
Reviewed-by Jason Gunthorpe <[email protected]>
Signed-off-by Robin Murphy <[email protected]>
---
 drivers/of/device.c | 19 ++++++++-----------
 1 file changed, 8 insertions(+), 11 deletions(-)
drivers/of/device.c +8 -11
index 526a42cdf66e..51062a831970 100644
@@ -97,7 +97,7 @@ int of_dma_configure_id(struct device *dev, struct device_node *np,
 	const struct bus_dma_region *map = NULL;
 	struct device_node *bus_np;
 	u64 dma_start = 0;
-	u64 mask, end, size = 0;
+	u64 mask, end = 0;
 	bool coherent;
 	int ret;
 

@@ -118,17 +118,15 @@ int of_dma_configure_id(struct device *dev, struct device_node *np,
 			return ret == -ENODEV ? 0 : ret;
 	} else {
 		const struct bus_dma_region *r = map;
-		u64 dma_end = 0;
 
 		/* Determine the overall bounds of all DMA regions */
 		for (dma_start = ~0; r->size; r++) {
 			/* Take lower and upper limits */
 			if (r->dma_start < dma_start)
 				dma_start = r->dma_start;
-			if (r->dma_start + r->size > dma_end)
-				dma_end = r->dma_start + r->size;
+			if (r->dma_start + r->size > end)
+				end = r->dma_start + r->size;
 		}
-		size = dma_end - dma_start;
 	}
 
 	/*

@@ -142,16 +140,15 @@ int of_dma_configure_id(struct device *dev, struct device_node *np,
 		dev->dma_mask = &dev->coherent_dma_mask;
 	}
 
-	if (!size && dev->coherent_dma_mask)
-		size = max(dev->coherent_dma_mask, dev->coherent_dma_mask + 1);
-	else if (!size)
-		size = 1ULL << 32;
+	if (!end && dev->coherent_dma_mask)
+		end = dev->coherent_dma_mask;
+	else if (!end)
+		end = (1ULL << 32) - 1;
 
 	/*
 	 * Limit coherent and dma mask based on size and default mask
 	 * set by the driver.
 	 */
-	end = dma_start + size - 1;
 	mask = DMA_BIT_MASK(ilog2(end) + 1);
 	dev->coherent_dma_mask &= mask;
 	*dev->dma_mask &= mask;

@@ -177,7 +174,7 @@ 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, end - dma_start + 1, iommu, coherent);
 
 	if (!iommu)
 		of_dma_set_restricted_buffer(dev, np);
Signature · 1 line
2.39.2.101.g768bb238c484.dirty
author maintainer
#3 lore raw

PATCH v2 3/7 ACPI/IORT: Handle memory address size limits as limits

In reply to Robin Murphy

Return the Root Complex/Named Component memory address size limit as an inclusive limit value, rather than an exclusive size. This saves having to fudge an off-by-one for the 64-bit case, and simplifies our caller.

Reviewed-by Jason Gunthorpe <[email protected]>
Signed-off-by Robin Murphy <[email protected]>

---
v2: Avoid undefined shifts (grr...)

---
 drivers/acpi/arm64/dma.c  |  9 +++------
 drivers/acpi/arm64/iort.c | 20 ++++++++++----------
 include/linux/acpi_iort.h |  4 ++--
 3 files changed, 15 insertions(+), 18 deletions(-)
drivers/acpi/arm64/dma.c +3 -6
index 93d796531af3..b98a149f8d50 100644
@@ -8,7 +8,6 @@ void acpi_arch_dma_setup(struct device *dev)
 {
 	int ret;
 	u64 end, mask;
-	u64 size = 0;
 	const struct bus_dma_region *map = NULL;
 
 	/*

@@ -23,9 +22,9 @@ void acpi_arch_dma_setup(struct device *dev)
 	}
 
 	if (dev->coherent_dma_mask)
-		size = max(dev->coherent_dma_mask, dev->coherent_dma_mask + 1);
+		end = dev->coherent_dma_mask;
 	else
-		size = 1ULL << 32;
+		end = (1ULL << 32) - 1;
 
 	ret = acpi_dma_get_range(dev, &map);
 	if (!ret && map) {

@@ -36,18 +35,16 @@ void acpi_arch_dma_setup(struct device *dev)
 				end = r->dma_start + r->size - 1;
 		}
 
-		size = end + 1;
 		dev->dma_range_map = map;
 	}
 
 	if (ret == -ENODEV)
-		ret = iort_dma_get_ranges(dev, &size);
+		ret = iort_dma_get_ranges(dev, &end);
 	if (!ret) {
 		/*
 		 * Limit coherent and dma mask based on size retrieved from
 		 * firmware.
 		 */
-		end = size - 1;
 		mask = DMA_BIT_MASK(ilog2(end) + 1);
 		dev->bus_dma_limit = end;
 		dev->coherent_dma_mask = min(dev->coherent_dma_mask, mask);
drivers/acpi/arm64/iort.c +10 -10
index 6496ff5a6ba2..c0b1c2c19444 100644
@@ -1367,7 +1367,7 @@ 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)
+static int nc_dma_get_range(struct device *dev, u64 *limit)
 {
 	struct acpi_iort_node *node;
 	struct acpi_iort_named_component *ncomp;

@@ -1384,13 +1384,13 @@ static int nc_dma_get_range(struct device *dev, u64 *size)
 		return -EINVAL;
 	}
 
-	*size = ncomp->memory_address_limit >= 64 ? U64_MAX :
-			1ULL<<ncomp->memory_address_limit;
+	*limit = ncomp->memory_address_limit >= 64 ? U64_MAX :
+			(1ULL << ncomp->memory_address_limit) - 1;
 
 	return 0;
 }
 
-static int rc_dma_get_range(struct device *dev, u64 *size)
+static int rc_dma_get_range(struct device *dev, u64 *limit)
 {
 	struct acpi_iort_node *node;
 	struct acpi_iort_root_complex *rc;

@@ -1408,8 +1408,8 @@ static int rc_dma_get_range(struct device *dev, u64 *size)
 		return -EINVAL;
 	}
 
-	*size = rc->memory_address_limit >= 64 ? U64_MAX :
-			1ULL<<rc->memory_address_limit;
+	*limit = rc->memory_address_limit >= 64 ? U64_MAX :
+			(1ULL << rc->memory_address_limit) - 1;
 
 	return 0;
 }

@@ -1417,16 +1417,16 @@ static int rc_dma_get_range(struct device *dev, u64 *size)
 /**
  * iort_dma_get_ranges() - Look up DMA addressing limit for the device
  * @dev: device to lookup
- * @size: DMA range size result pointer
+ * @limit: DMA limit result pointer
  *
  * Return: 0 on success, an error otherwise.
  */
-int iort_dma_get_ranges(struct device *dev, u64 *size)
+int iort_dma_get_ranges(struct device *dev, u64 *limit)
 {
 	if (dev_is_pci(dev))
-		return rc_dma_get_range(dev, size);
+		return rc_dma_get_range(dev, limit);
 	else
-		return nc_dma_get_range(dev, size);
+		return nc_dma_get_range(dev, limit);
 }
 
 static void __init acpi_iort_register_irq(int hwirq, const char *name,
include/linux/acpi_iort.h +2 -2
index 1cb65592c95d..d4ed5622cf2b 100644
@@ -39,7 +39,7 @@ void iort_get_rmr_sids(struct fwnode_handle *iommu_fwnode,
 void iort_put_rmr_sids(struct fwnode_handle *iommu_fwnode,
 		       struct list_head *head);
 /* IOMMU interface */
-int iort_dma_get_ranges(struct device *dev, u64 *size);
+int iort_dma_get_ranges(struct device *dev, u64 *limit);
 int iort_iommu_configure_id(struct device *dev, const u32 *id_in);
 void iort_iommu_get_resv_regions(struct device *dev, struct list_head *head);
 phys_addr_t acpi_iort_dma_get_max_cpu_address(void);

@@ -55,7 +55,7 @@ void iort_get_rmr_sids(struct fwnode_handle *iommu_fwnode, struct list_head *hea
 static inline
 void iort_put_rmr_sids(struct fwnode_handle *iommu_fwnode, struct list_head *head) { }
 /* IOMMU interface */
-static inline int iort_dma_get_ranges(struct device *dev, u64 *size)
+static inline int iort_dma_get_ranges(struct device *dev, u64 *limit)
 { return -ENODEV; }
 static inline int iort_iommu_configure_id(struct device *dev, const u32 *id_in)
 { return -ENODEV; }
Signature · 1 line
2.39.2.101.g768bb238c484.dirty
author maintainer
#4 lore raw

PATCH v2 4/7 dma-mapping: Add helpers for dma_range_map bounds

In reply to Robin Murphy

Several places want to compute the lower and/or upper bounds of a dma_range_map, so let's factor that out into reusable helpers.

Reviewed-by Christoph Hellwig <[email protected]>
Reviewed-by Jason Gunthorpe <[email protected]>
Signed-off-by Robin Murphy <[email protected]>

---
v2: fix warning for 32-bit builds

---
 arch/loongarch/kernel/dma.c |  9 ++-------
 drivers/acpi/arm64/dma.c    |  8 +-------
 drivers/of/device.c         | 11 ++---------
 include/linux/dma-direct.h  | 18 ++++++++++++++++++
 4 files changed, 23 insertions(+), 23 deletions(-)
arch/loongarch/kernel/dma.c +2 -7
index 7a9c6a9dd2d0..429555fb4e13 100644
@@ -8,17 +8,12 @@
 void acpi_arch_dma_setup(struct device *dev)
 {
 	int ret;
-	u64 mask, end = 0;
+	u64 mask, end;
 	const struct bus_dma_region *map = NULL;
 
 	ret = acpi_dma_get_range(dev, &map);
 	if (!ret && map) {
-		const struct bus_dma_region *r = map;
-
-		for (end = 0; r->size; r++) {
-			if (r->dma_start + r->size - 1 > end)
-				end = r->dma_start + r->size - 1;
-		}
+		end = dma_range_map_max(map);
 
 		mask = DMA_BIT_MASK(ilog2(end) + 1);
 		dev->bus_dma_limit = end;
drivers/acpi/arm64/dma.c +1 -7
index b98a149f8d50..52b2abf88689 100644
@@ -28,13 +28,7 @@ void acpi_arch_dma_setup(struct device *dev)
 
 	ret = acpi_dma_get_range(dev, &map);
 	if (!ret && map) {
-		const struct bus_dma_region *r = map;
-
-		for (end = 0; r->size; r++) {
-			if (r->dma_start + r->size - 1 > end)
-				end = r->dma_start + r->size - 1;
-		}
-
+		end = dma_range_map_max(map);
 		dev->dma_range_map = map;
 	}
drivers/of/device.c +2 -9
index 51062a831970..66879edb4a61 100644
@@ -117,16 +117,9 @@ int of_dma_configure_id(struct device *dev, struct device_node *np,
 		if (!force_dma)
 			return ret == -ENODEV ? 0 : ret;
 	} else {
-		const struct bus_dma_region *r = map;
-
 		/* Determine the overall bounds of all DMA regions */
-		for (dma_start = ~0; r->size; r++) {
-			/* Take lower and upper limits */
-			if (r->dma_start < dma_start)
-				dma_start = r->dma_start;
-			if (r->dma_start + r->size > end)
-				end = r->dma_start + r->size;
-		}
+		dma_start = dma_range_map_min(map);
+		end = dma_range_map_max(map);
 	}
 
 	/*
include/linux/dma-direct.h +18 -0
index 3eb3589ff43e..edbe13d00776 100644
@@ -54,6 +54,24 @@ static inline phys_addr_t translate_dma_to_phys(struct device *dev,
 	return (phys_addr_t)-1;
 }
 
+static inline dma_addr_t dma_range_map_min(const struct bus_dma_region *map)
+{
+	dma_addr_t ret = (dma_addr_t)U64_MAX;
+
+	for (; map->size; map++)
+		ret = min(ret, map->dma_start);
+	return ret;
+}
+
+static inline dma_addr_t dma_range_map_max(const struct bus_dma_region *map)
+{
+	dma_addr_t ret = 0;
+
+	for (; map->size; map++)
+		ret = max(ret, map->dma_start + map->size - 1);
+	return ret;
+}
+
 #ifdef CONFIG_ARCH_HAS_PHYS_TO_DMA
 #include <asm/dma-direct.h>
 #ifndef phys_to_dma_unencrypted
Signature · 1 line
2.39.2.101.g768bb238c484.dirty
maintainer Acked-by on v2 4/7
#5 lore raw

Re: [PATCH v2 4/7] dma-mapping: Add helpers for dma_range_map bounds

Quoted 6 lines · Robin Murphy

Several places want to compute the lower and/or upper bounds of a dma_range_map, so let's factor that out into reusable helpers.

Reviewed-by Christoph Hellwig <[email protected]>
Reviewed-by Jason Gunthorpe <[email protected]>
Signed-off-by Robin Murphy <[email protected]>
Quoted 9 lines

---
v2: fix warning for 32-bit builds

---
 arch/loongarch/kernel/dma.c |  9 ++-------
 drivers/acpi/arm64/dma.c    |  8 +-------
 drivers/of/device.c         | 11 ++---------
 include/linux/dma-direct.h  | 18 ++++++++++++++++++
 4 files changed, 23 insertions(+), 23 deletions(-)
Acked-by Rob Herring <[email protected]>
author maintainer
#6 lore raw

PATCH v2 5/7 iommu/dma: Make limit checks self-contained

In reply to Robin Murphy

It's now easy to retrieve the device's DMA limits if we want to check them against the domain aperture, so do that ourselves instead of relying on them being passed through the callchain.

Reviewed-by Jason Gunthorpe <[email protected]>
Signed-off-by Robin Murphy <[email protected]>
---
 drivers/iommu/dma-iommu.c | 21 +++++++++------------
 1 file changed, 9 insertions(+), 12 deletions(-)
drivers/iommu/dma-iommu.c +9 -12
index 5dc012220ca9..27a167f4cd3e 100644
@@ -659,19 +659,16 @@ static void iommu_dma_init_options(struct iommu_dma_options *options,
 /**
  * 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
- * @limit: Last address of the IOVA space
  * @dev: Device the domain is being initialised for
  *
- * @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
+ * If the geometry and dma_range_map include address 0, we reserve that page
  * 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,
-				 dma_addr_t limit, struct device *dev)
+static int iommu_dma_init_domain(struct iommu_domain *domain, struct device *dev)
 {
 	struct iommu_dma_cookie *cookie = domain->iova_cookie;
+	const struct bus_dma_region *map = dev->dma_range_map;
 	unsigned long order, base_pfn;
 	struct iova_domain *iovad;
 	int ret;

@@ -683,18 +680,18 @@ static int iommu_dma_init_domain(struct iommu_domain *domain, dma_addr_t base,
 
 	/* Use the smallest supported page size for IOVA granularity */
 	order = __ffs(domain->pgsize_bitmap);
-	base_pfn = max_t(unsigned long, 1, base >> order);
+	base_pfn = 1;
 
 	/* Check the domain allows at least some access to the device... */
-	if (domain->geometry.force_aperture) {
+	if (map) {
+		dma_addr_t base = dma_range_map_min(map);
 		if (base > domain->geometry.aperture_end ||
-		    limit < domain->geometry.aperture_start) {
+		    dma_range_map_max(map) < domain->geometry.aperture_start) {
 			pr_warn("specified DMA range outside IOMMU capability\n");
 			return -EFAULT;
 		}
 		/* ...then finally give it a kicking to make sure it fits */
-		base_pfn = max_t(unsigned long, base_pfn,
-				domain->geometry.aperture_start >> order);
+		base_pfn = max(base, domain->geometry.aperture_start) >> order;
 	}
 
 	/* start_pfn is always nonzero for an already-initialised domain */

@@ -1743,7 +1740,7 @@ void iommu_setup_dma_ops(struct device *dev, u64 dma_base, u64 dma_limit)
 	 * underlying IOMMU driver needs to support via the dma-iommu layer.
 	 */
 	if (iommu_is_dma_domain(domain)) {
-		if (iommu_dma_init_domain(domain, dma_base, dma_limit, dev))
+		if (iommu_dma_init_domain(domain, dev))
 			goto out_err;
 		dev->dma_ops = &iommu_dma_ops;
 	}
Signature · 1 line
2.39.2.101.g768bb238c484.dirty
author maintainer
#7 lore raw

PATCH v2 6/7 iommu/dma: Centralise iommu_setup_dma_ops()

In reply to Robin Murphy

It's somewhat hard to see, but arm64's arch_setup_dma_ops() should only ever call iommu_setup_dma_ops() after a successful iommu_probe_device(), which means there should be no harm in achieving the same orer of operations by running it off the back of iommu_probe_device() itself. This then puts it in line with the x86 and s390 .probe_finalize bodges, letting us pull it all into the main flow properly. As a bonus this lets us fold in and de-scope the PCI workaround setup as well.

At this point we can also then pull the call inside the group mutex, and avoid having to think about whether iommu_group_store_type() could theroetically race and free the domain where iommu_setup_dma_ops() may currently run just *before* iommu_device_use_default_domain() claims it.

Signed-off-by Robin Murphy <[email protected]>

---
v2: Shuffle around to make sure the iommu_group_do_probe_finalize() cases
are covered as well, with bonus side-effects as above.

---
 arch/arm64/mm/dma-mapping.c  |  2 --
 drivers/iommu/amd/iommu.c    |  8 --------
 drivers/iommu/dma-iommu.c    | 18 ++++++------------
 drivers/iommu/dma-iommu.h    | 14 ++++++--------
 drivers/iommu/intel/iommu.c  |  7 -------
 drivers/iommu/iommu.c        |  6 +++---
 drivers/iommu/s390-iommu.c   |  6 ------
 drivers/iommu/virtio-iommu.c | 10 ----------
 include/linux/iommu.h        |  7 -------
 9 files changed, 15 insertions(+), 63 deletions(-)
arch/arm64/mm/dma-mapping.c +0 -2
index 3cb101e8cb29..96ff791199e8 100644
@@ -58,8 +58,6 @@ void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
 		   ARCH_DMA_MINALIGN, cls);
 
 	dev->dma_coherent = coherent;
-	if (iommu)
-		iommu_setup_dma_ops(dev, dma_base, dma_base + size - 1);
 
 	xen_setup_dma_ops(dev);
 }
drivers/iommu/amd/iommu.c +0 -8
index fcc987f5d4ed..9418808009ba 100644
@@ -1985,13 +1985,6 @@ static struct iommu_device *amd_iommu_probe_device(struct device *dev)
 	return iommu_dev;
 }
 
-static void amd_iommu_probe_finalize(struct device *dev)
-{
-	/* Domains are initialized for this device - have a look what we ended up with */
-	set_dma_ops(dev, NULL);
-	iommu_setup_dma_ops(dev, 0, U64_MAX);
-}
-
 static void amd_iommu_release_device(struct device *dev)
 {
 	struct amd_iommu *iommu;

@@ -2646,7 +2639,6 @@ const struct iommu_ops amd_iommu_ops = {
 	.domain_alloc_user = amd_iommu_domain_alloc_user,
 	.probe_device = amd_iommu_probe_device,
 	.release_device = amd_iommu_release_device,
-	.probe_finalize = amd_iommu_probe_finalize,
 	.device_group = amd_iommu_device_group,
 	.get_resv_regions = amd_iommu_get_resv_regions,
 	.is_attach_deferred = amd_iommu_is_attach_deferred,
drivers/iommu/dma-iommu.c +6 -12
index 27a167f4cd3e..d808c8dcf5cb 100644
@@ -1724,25 +1724,20 @@ static const struct dma_map_ops iommu_dma_ops = {
 	.opt_mapping_size	= iommu_dma_opt_mapping_size,
 };
 
-/*
- * 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 dma_limit)
+void iommu_setup_dma_ops(struct device *dev)
 {
 	struct iommu_domain *domain = iommu_get_domain_for_dev(dev);
 
-	if (!domain)
-		goto out_err;
+	if (dev_is_pci(dev))
+		dev->iommu->pci_32bit_workaround = !iommu_dma_forcedac;
 
-	/*
-	 * The IOMMU core code allocates the default DMA domain, which the
-	 * underlying IOMMU driver needs to support via the dma-iommu layer.
-	 */
 	if (iommu_is_dma_domain(domain)) {
 		if (iommu_dma_init_domain(domain, dev))
 			goto out_err;
 		dev->dma_ops = &iommu_dma_ops;
+	} else if (dev->dma_ops == &iommu_dma_ops) {
+		/* Clean up if we've switched *from* a DMA domain */
+		dev->dma_ops = NULL;
 	}
 
 	return;

@@ -1750,7 +1745,6 @@ 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)
drivers/iommu/dma-iommu.h +6 -8
index c829f1f82a99..c12d63457c76 100644
@@ -9,6 +9,8 @@
 
 #ifdef CONFIG_IOMMU_DMA
 
+void iommu_setup_dma_ops(struct device *dev);
+
 int iommu_get_dma_cookie(struct iommu_domain *domain);
 void iommu_put_dma_cookie(struct iommu_domain *domain);
 

@@ -17,13 +19,13 @@ int iommu_dma_init_fq(struct iommu_domain *domain);
 void iommu_dma_get_resv_regions(struct device *dev, struct list_head *list);
 
 extern bool iommu_dma_forcedac;
-static inline void iommu_dma_set_pci_32bit_workaround(struct device *dev)
-{
-	dev->iommu->pci_32bit_workaround = !iommu_dma_forcedac;
-}
 
 #else /* CONFIG_IOMMU_DMA */
 
+static inline void iommu_setup_dma_ops(struct device *dev)
+{
+}
+
 static inline int iommu_dma_init_fq(struct iommu_domain *domain)
 {
 	return -EINVAL;

@@ -42,9 +44,5 @@ static inline void iommu_dma_get_resv_regions(struct device *dev, struct list_he
 {
 }
 
-static inline void iommu_dma_set_pci_32bit_workaround(struct device *dev)
-{
-}
-
 #endif	/* CONFIG_IOMMU_DMA */
 #endif	/* __DMA_IOMMU_H */
drivers/iommu/intel/iommu.c +0 -7
index 3531b956556c..f7347ed41e89 100644
@@ -4480,12 +4480,6 @@ static void intel_iommu_release_device(struct device *dev)
 	set_dma_ops(dev, NULL);
 }
 
-static void intel_iommu_probe_finalize(struct device *dev)
-{
-	set_dma_ops(dev, NULL);
-	iommu_setup_dma_ops(dev, 0, U64_MAX);
-}
-
 static void intel_iommu_get_resv_regions(struct device *device,
 					 struct list_head *head)
 {

@@ -4937,7 +4931,6 @@ const struct iommu_ops intel_iommu_ops = {
 	.domain_alloc		= intel_iommu_domain_alloc,
 	.domain_alloc_user	= intel_iommu_domain_alloc_user,
 	.probe_device		= intel_iommu_probe_device,
-	.probe_finalize		= intel_iommu_probe_finalize,
 	.release_device		= intel_iommu_release_device,
 	.get_resv_regions	= intel_iommu_get_resv_regions,
 	.device_group		= intel_iommu_device_group,
drivers/iommu/iommu.c +3 -3
index 824989874dee..43f630d0530e 100644
@@ -560,10 +560,10 @@ static int __iommu_probe_device(struct device *dev, struct list_head *group_list
 		if (list_empty(&group->entry))
 			list_add_tail(&group->entry, group_list);
 	}
-	mutex_unlock(&group->mutex);
 
-	if (dev_is_pci(dev))
-		iommu_dma_set_pci_32bit_workaround(dev);
+	iommu_setup_dma_ops(dev);
+
+	mutex_unlock(&group->mutex);
 
 	return 0;
drivers/iommu/s390-iommu.c +0 -6
index 9a5196f523de..d8eaa7ea380b 100644
@@ -695,11 +695,6 @@ static size_t s390_iommu_unmap_pages(struct iommu_domain *domain,
 	return size;
 }
 
-static void s390_iommu_probe_finalize(struct device *dev)
-{
-	iommu_setup_dma_ops(dev, 0, U64_MAX);
-}
-
 struct zpci_iommu_ctrs *zpci_get_iommu_ctrs(struct zpci_dev *zdev)
 {
 	if (!zdev || !zdev->s390_domain)

@@ -785,7 +780,6 @@ static const struct iommu_ops s390_iommu_ops = {
 	.capable = s390_iommu_capable,
 	.domain_alloc_paging = s390_domain_alloc_paging,
 	.probe_device = s390_iommu_probe_device,
-	.probe_finalize = s390_iommu_probe_finalize,
 	.release_device = s390_iommu_release_device,
 	.device_group = generic_device_group,
 	.pgsize_bitmap = SZ_4K,
drivers/iommu/virtio-iommu.c +0 -10
index 9bcffdde6175..5a558456946b 100644
@@ -998,15 +998,6 @@ 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
-	/* First clear the DMA ops in case we're switching from a DMA domain */
-	set_dma_ops(dev, NULL);
-	iommu_setup_dma_ops(dev, 0, U64_MAX);
-#endif
-}
-
 static void viommu_release_device(struct device *dev)
 {
 	struct viommu_endpoint *vdev = dev_iommu_priv_get(dev);

@@ -1043,7 +1034,6 @@ static struct iommu_ops viommu_ops = {
 	.capable		= viommu_capable,
 	.domain_alloc		= viommu_domain_alloc,
 	.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,
include/linux/iommu.h +0 -7
index 20ed3a4fc5e0..3a3bf8afb8ca 100644
@@ -1283,9 +1283,6 @@ static inline void iommu_debugfs_setup(void) {}
 #ifdef CONFIG_IOMMU_DMA
 #include <linux/msi.h>
 
-/* Setup call for arch DMA mapping code */
-void iommu_setup_dma_ops(struct device *dev, u64 dma_base, u64 dma_limit);
-
 int iommu_get_msi_cookie(struct iommu_domain *domain, dma_addr_t base);
 
 int iommu_dma_prepare_msi(struct msi_desc *desc, phys_addr_t msi_addr);

@@ -1296,10 +1293,6 @@ void iommu_dma_compose_msi_msg(struct msi_desc *desc, struct msi_msg *msg);
 struct msi_desc;
 struct msi_msg;
 
-static inline void iommu_setup_dma_ops(struct device *dev, u64 dma_base, u64 dma_limit)
-{
-}
-
 static inline int iommu_get_msi_cookie(struct iommu_domain *domain, dma_addr_t base)
 {
 	return -ENODEV;
Signature · 1 line
2.39.2.101.g768bb238c484.dirty
#8 lore raw

Re: [PATCH v2 6/7] iommu/dma: Centralise iommu_setup_dma_ops()

Quoted 27 lines · Robin Murphy
drivers/iommu/dma-iommu.c +3 -11
index 27a167f4cd3e..d808c8dcf5cb 100644
@@ -1724,25 +1724,20 @@ static const struct dma_map_ops iommu_dma_ops = {
 	.opt_mapping_size	= iommu_dma_opt_mapping_size,
 };
 
-/*
- * 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 dma_limit)
+void iommu_setup_dma_ops(struct device *dev)
 {
 	struct iommu_domain *domain = iommu_get_domain_for_dev(dev);
 
-	if (!domain)
-		goto out_err;
+	if (dev_is_pci(dev))
+		dev->iommu->pci_32bit_workaround = !iommu_dma_forcedac;
 
-	/*
-	 * The IOMMU core code allocates the default DMA domain, which the
-	 * underlying IOMMU driver needs to support via the dma-iommu layer.
-	 */
 	if (iommu_is_dma_domain(domain)) {

...

drivers/iommu/iommu.c static int __iommu_probe_device(struct device *dev, struct list_head *group_list · line 564

Quoted 13 lines
drivers/iommu/iommu.c +1 -3
index 824989874dee..43f630d0530e 100644
@@ -560,10 +560,10 @@ static int __iommu_probe_device(struct device *dev, struct list_head *group_list
 		if (list_empty(&group->entry))
 			list_add_tail(&group->entry, group_list);
 	}
-	mutex_unlock(&group->mutex);
 
-	if (dev_is_pci(dev))
-		iommu_dma_set_pci_32bit_workaround(dev);
+	iommu_setup_dma_ops(dev);

With Intel VT-d (QEMU emulation) I get a crash in iommu_setup_dma_ops() because at this point group->domain and group->default_domain are still NULL, group_list is non-NULL.

No problem with x86 virtio-iommu, it goes through iommu_setup_default_domain() earlier in the function. Arm virtio-iommu is fine too.

Thanks,
Jean

author maintainer
#9 lore raw

Re: [PATCH v2 6/7] iommu/dma: Centralise iommu_setup_dma_ops()

Quoted 41 lines · Jean-Philippe Brucker
Quoted 27 lines · Robin Murphy
drivers/iommu/dma-iommu.c +3 -11
index 27a167f4cd3e..d808c8dcf5cb 100644
@@ -1724,25 +1724,20 @@ static const struct dma_map_ops iommu_dma_ops = {
  	.opt_mapping_size	= iommu_dma_opt_mapping_size,
  };
 
-/*
- * 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 dma_limit)
+void iommu_setup_dma_ops(struct device *dev)
  {
  	struct iommu_domain *domain = iommu_get_domain_for_dev(dev);
 
-	if (!domain)
-		goto out_err;
+	if (dev_is_pci(dev))
+		dev->iommu->pci_32bit_workaround = !iommu_dma_forcedac;
 
-	/*
-	 * The IOMMU core code allocates the default DMA domain, which the
-	 * underlying IOMMU driver needs to support via the dma-iommu layer.
-	 */
  	if (iommu_is_dma_domain(domain)) {

...

Quoted 10 lines
drivers/iommu/iommu.c +0 -1
index 824989874dee..43f630d0530e 100644
@@ -560,10 +560,10 @@ static int __iommu_probe_device(struct device *dev, struct list_head *group_list
  		if (list_empty(&group->entry))
  			list_add_tail(&group->entry, group_list);
  	}
-	mutex_unlock(&group->mutex);
Quoted 7 lines

drivers/iommu/iommu.c static int __iommu_probe_device(struct device *dev, struct list_head *group_list · line 564

Quoted 3 lines
drivers/iommu/iommu.c +1 -2
-	if (dev_is_pci(dev))
-		iommu_dma_set_pci_32bit_workaround(dev);
+	iommu_setup_dma_ops(dev);

With Intel VT-d (QEMU emulation) I get a crash in iommu_setup_dma_ops() because at this point group->domain and group->default_domain are still NULL, group_list is non-NULL.

Ugh, clearly I'd manage to confuse myself, since what I wrote in the changelog isn't even right...

Taking yet another look, there's not actually one single place we can do this right now which will work in a manageable way for all cases. With 2 or 3 more levels of mess unpicked it's going to clean up much further (it's also becoming clear that iommu-dma wants better separation of its own per-device and per-domain bits), but for the immediate task in this series of finally getting out of arch code, I guess that continuing to echo the current probe_finalize flows is going to be safest. Something like the diff below (but I'll have a further think about it with a fresh head tomorrow).

Thanks,
Robin.

----->8-----

drivers/iommu/iommu.c +5 -11
index 8972b7f22a9a..ba4cd5251205 100644
@@ -562,7 +562,8 @@ static int __iommu_probe_device(struct device *dev, struct list_head *group_list
 			list_add_tail(&group->entry, group_list);
 	}
 
-	iommu_setup_dma_ops(dev);
+	if (group->default_domain)
+		iommu_setup_dma_ops(dev);
 
 	mutex_unlock(&group->mutex);
 

@@ -1992,6 +1993,8 @@ int bus_iommu_probe(const struct bus_type *bus)
 			mutex_unlock(&group->mutex);
 			return ret;
 		}
+		for_each_group_device(group, gdev)
+			iommu_setup_dma_ops(gdev->dev);
 		mutex_unlock(&group->mutex);
 
 		/*

@@ -3217,18 +3220,9 @@ static ssize_t iommu_group_store_type(struct iommu_group *group,
 	if (ret)
 		goto out_unlock;
 
-	/*
-	 * Release the mutex here because ops->probe_finalize() call-back of
-	 * some vendor IOMMU drivers calls arm_iommu_attach_device() which
-	 * in-turn might call back into IOMMU core code, where it tries to take
-	 * group->mutex, resulting in a deadlock.
-	 */
-	mutex_unlock(&group->mutex);
-
 	/* Make sure dma_ops is appropriatley set */
 	for_each_group_device(group, gdev)
-		iommu_group_do_probe_finalize(gdev->dev);
-	return count;
+		iommu_setup_dma_ops(gdev->dev);
 
 out_unlock:
 	mutex_unlock(&group->mutex);
#10 lore raw

Re: [PATCH v2 6/7] iommu/dma: Centralise iommu_setup_dma_ops()

Quoted 2 lines · Robin Murphy

Taking yet another look, there's not actually one single place we can do this right now which will work in a manageable way for all cases.

The dma ops should be set after changing the translation and there is only one place that attachs the domain? What prevents putting it there?

Quoted 5 lines
drivers/iommu/iommu.c +0 -2
@@ -3217,18 +3220,9 @@ static ssize_t iommu_group_store_type(struct iommu_group *group,
 	if (ret)
 		goto out_unlock;
-	/*
-	 * Release the mutex here because ops->probe_finalize() call-back of

drivers/iommu/iommu.c static ssize_t iommu_group_store_type(struct iommu_group *group, · line 3230

Quoted 10 lines
drivers/iommu/iommu.c +0 -8
-	 * some vendor IOMMU drivers calls arm_iommu_attach_device() which
-	 * in-turn might call back into IOMMU core code, where it tries to take
-	 * group->mutex, resulting in a deadlock.
-	 */
-	mutex_unlock(&group->mutex);
-
 	/* Make sure dma_ops is appropriatley set */
 	for_each_group_device(group, gdev)
-		iommu_group_do_probe_finalize(gdev->dev);
-	return count;

If we are turning this into something that only works for the ARM DMA then the remaining caller should be guarded by an IS_ENABLED

Jason

author maintainer
#11 lore raw

PATCH v2 7/7 dma-mapping: Simplify arch_setup_dma_ops()

In reply to Robin Murphy

The dma_base, size and iommu arguments are only used by ARM, and can now easily be deduced from the device itself, so there's no need to pass them through the callchain as well.

Reviewed-by Christoph Hellwig <[email protected]>
Signed-off-by Robin Murphy <[email protected]>

---
v2: Make sure the ARM changes actually build (oops...)

---
 arch/arc/mm/dma.c               |  3 +--
 arch/arm/mm/dma-mapping-nommu.c |  3 +--
 arch/arm/mm/dma-mapping.c       | 18 ++++++++++--------
 arch/arm64/mm/dma-mapping.c     |  3 +--
 arch/mips/mm/dma-noncoherent.c  |  3 +--
 arch/riscv/mm/dma-noncoherent.c |  3 +--
 drivers/acpi/scan.c             |  3 +--
 drivers/hv/hv_common.c          |  6 +-----
 drivers/of/device.c             |  4 +---
 include/linux/dma-map-ops.h     |  6 ++----
 10 files changed, 20 insertions(+), 32 deletions(-)
arch/arc/mm/dma.c +1 -2
index 2a7fbbb83b70..6b85e94f3275 100644
@@ -90,8 +90,7 @@ 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)
+void arch_setup_dma_ops(struct device *dev, bool coherent)
 {
 	/*
 	 * IOC hardware snoops all DMA traffic keeping the caches consistent
arch/arm/mm/dma-mapping-nommu.c +1 -2
index cfd9c933d2f0..97db5397c320 100644
@@ -33,8 +33,7 @@ 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)
+void arch_setup_dma_ops(struct device *dev, bool coherent)
 {
 	if (IS_ENABLED(CONFIG_CPU_V7M)) {
 		/*
arch/arm/mm/dma-mapping.c +10 -8
index 5409225b4abc..5ac482d7ff94 100644
@@ -1712,11 +1712,15 @@ 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)
+static void arm_setup_iommu_dma_ops(struct device *dev)
 {
 	struct dma_iommu_mapping *mapping;
+	u64 dma_base = 0, size = 1ULL << 32;
 
+	if (dev->dma_range_map) {
+		dma_base = dma_range_map_min(dev->dma_range_map);
+		size = dma_range_map_max(dev->dma_range_map) - dma_base;
+	}
 	mapping = arm_iommu_create_mapping(dev->bus, dma_base, size);
 	if (IS_ERR(mapping)) {
 		pr_warn("Failed to create %llu-byte IOMMU mapping for device %s\n",

@@ -1747,8 +1751,7 @@ 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)
+static void arm_setup_iommu_dma_ops(struct device *dev)
 {
 }
 

@@ -1756,8 +1759,7 @@ 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)
+void arch_setup_dma_ops(struct device *dev, bool coherent)
 {
 	/*
 	 * Due to legacy code that sets the ->dma_coherent flag from a bus

@@ -1776,8 +1778,8 @@ 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);
 
 	xen_setup_dma_ops(dev);
 	dev->archdata.dma_ops_setup = true;
arch/arm64/mm/dma-mapping.c +1 -2
index 96ff791199e8..0b320a25a471 100644
@@ -46,8 +46,7 @@ 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)
+void arch_setup_dma_ops(struct device *dev, bool coherent)
 {
 	int cls = cache_line_size_of_cpu();
arch/mips/mm/dma-noncoherent.c +1 -2
index 3c4fc97b9f39..ab4f2a75a7d0 100644
@@ -137,8 +137,7 @@ void arch_sync_dma_for_cpu(phys_addr_t paddr, size_t size,
 #endif
 
 #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)
+void arch_setup_dma_ops(struct device *dev, bool coherent)
 {
 	dev->dma_coherent = coherent;
 }
arch/riscv/mm/dma-noncoherent.c +1 -2
index 4e4e469b8dd6..cb89d7e0ba88 100644
@@ -128,8 +128,7 @@ void arch_dma_prep_coherent(struct page *page, size_t size)
 	ALT_CMO_OP(FLUSH, flush_addr, size, riscv_cbom_block_size);
 }
 
-void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
-		const struct iommu_ops *iommu, bool coherent)
+void arch_setup_dma_ops(struct device *dev, bool coherent)
 {
 	WARN_TAINT(!coherent && riscv_cbom_block_size > ARCH_DMA_MINALIGN,
 		   TAINT_CPU_OUT_OF_SPEC,
drivers/acpi/scan.c +1 -2
index ee88a727f200..cad171fc31e8 100644
@@ -1640,8 +1640,7 @@ 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, attr == DEV_DMA_COHERENT);
 
 	return 0;
 }
drivers/hv/hv_common.c +1 -5
index 4372f5d146ab..0e2decd1167a 100644
@@ -484,11 +484,7 @@ EXPORT_SYMBOL_GPL(hv_query_ext_cap);
 
 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, coherent);
 }
 EXPORT_SYMBOL_GPL(hv_setup_dma_ops);
drivers/of/device.c +1 -3
index 66879edb4a61..3394751015d3 100644
@@ -96,7 +96,6 @@ int of_dma_configure_id(struct device *dev, struct device_node *np,
 	const struct iommu_ops *iommu;
 	const struct bus_dma_region *map = NULL;
 	struct device_node *bus_np;
-	u64 dma_start = 0;
 	u64 mask, end = 0;
 	bool coherent;
 	int ret;

@@ -118,7 +117,6 @@ int of_dma_configure_id(struct device *dev, struct device_node *np,
 			return ret == -ENODEV ? 0 : ret;
 	} else {
 		/* Determine the overall bounds of all DMA regions */
-		dma_start = dma_range_map_min(map);
 		end = dma_range_map_max(map);
 	}
 

@@ -167,7 +165,7 @@ 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, end - dma_start + 1, iommu, coherent);
+	arch_setup_dma_ops(dev, coherent);
 
 	if (!iommu)
 		of_dma_set_restricted_buffer(dev, np);
include/linux/dma-map-ops.h +2 -4
index a52e508d1869..023f265eae2e 100644
@@ -426,11 +426,9 @@ bool arch_dma_unmap_sg_direct(struct device *dev, struct scatterlist *sg,
 #endif
 
 #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);
+void arch_setup_dma_ops(struct device *dev, 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)
+static inline void arch_setup_dma_ops(struct device *dev, bool coherent)
 {
 }
 #endif /* CONFIG_ARCH_HAS_SETUP_DMA_OPS */
Signature · 1 line
2.39.2.101.g768bb238c484.dirty
maintainer Acked-by on v2 7/7
#12 lore raw
Quoted 8 lines · Robin Murphy

The dma_base, size and iommu arguments are only used by ARM, and can now easily be deduced from the device itself, so there's no need to pass them through the callchain as well.

Reviewed-by Christoph Hellwig <[email protected]>
Signed-off-by Robin Murphy <[email protected]>

---
v2: Make sure the ARM changes actually build (oops...)

Quoted 13 lines
---
 arch/arc/mm/dma.c               |  3 +--
 arch/arm/mm/dma-mapping-nommu.c |  3 +--
 arch/arm/mm/dma-mapping.c       | 18 ++++++++++--------
 arch/arm64/mm/dma-mapping.c     |  3 +--
 arch/mips/mm/dma-noncoherent.c  |  3 +--
 arch/riscv/mm/dma-noncoherent.c |  3 +--
 drivers/acpi/scan.c             |  3 +--
 drivers/hv/hv_common.c          |  6 +-----
 drivers/of/device.c             |  4 +---
 include/linux/dma-map-ops.h     |  6 ++----
 10 files changed, 20 insertions(+), 32 deletions(-)
Acked-by Rob Herring <[email protected]>