diff mbox series

[v4,4/6] iommu/dma: Pass address limit rather than size to iommu_setup_dma_ops()

Message ID 20210610075130.67517-5-jean-philippe@linaro.org (mailing list archive)
State New
Headers show
Series Add support for ACPI VIOT | expand

Commit Message

Jean-Philippe Brucker June 10, 2021, 7:51 a.m. UTC
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@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(-)

Comments

Eric Auger June 16, 2021, 3:28 p.m. UTC | #1
Hi Jean,

On 6/10/21 9:51 AM, Jean-Philippe Brucker wrote:
> 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@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 4bf1dd3eb041..7bd1d2199141 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);
I don't get  size - dma_base - 1?
>  
>  #ifdef CONFIG_XEN
>  	if (xen_swiotlb_detect())
> diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c
> index 3ac42bbdefc6..94b96d81fcfd 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 be35284a2016..85f18342603c 100644
> --- a/drivers/iommu/intel/iommu.c
> +++ b/drivers/iommu/intel/iommu.c
> @@ -5171,7 +5171,7 @@ 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);
>  }
Thanks

Eric
diff mbox series

Patch

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 4bf1dd3eb041..7bd1d2199141 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_swiotlb_detect())
diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c
index 3ac42bbdefc6..94b96d81fcfd 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 be35284a2016..85f18342603c 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -5171,7 +5171,7 @@  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);
 }