diff mbox series

[v5,4/5] iommu/dma: Pass address limit rather than size to iommu_setup_dma_ops()

Message ID 20210618152059.1194210-5-jean-philippe@linaro.org (mailing list archive)
State New, archived
Headers show
Series Add support for ACPI VIOT | expand

Commit Message

Jean-Philippe Brucker June 18, 2021, 3:20 p.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.

The base and limit parameters are being phased out, because:
* they are redundant for x86 callers. dma-iommu already reserves the
  first page, and the upper limit is already in domain->geometry.
* they can now be obtained from dev->dma_range_map on Arm.
But removing them on Arm isn't completely straightforward so is left for
future work. As an intermediate step, simplify the x86 callers by
passing dummy limits.

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 |  5 +----
 5 files changed, 11 insertions(+), 14 deletions(-)

Comments

Robin Murphy June 18, 2021, 4:29 p.m. UTC | #1
On 2021-06-18 16:20, 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.
> 
> The base and limit parameters are being phased out, because:
> * they are redundant for x86 callers. dma-iommu already reserves the
>    first page, and the upper limit is already in domain->geometry.
> * they can now be obtained from dev->dma_range_map on Arm.
> But removing them on Arm isn't completely straightforward so is left for
> future work. As an intermediate step, simplify the x86 callers by
> passing dummy limits.

Reviewed-by: Robin Murphy <robin.murphy@arm.com>

> 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 |  5 +----
>   5 files changed, 11 insertions(+), 14 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..6719f9efea09 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, dma_base + size - 1);
>   
>   #ifdef CONFIG_XEN
>   	if (xen_swiotlb_detect())
> diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c
> index 3ac42bbdefc6..216323fb27ef 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, 0, 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..2f7213f0e7a1 100644
> --- a/drivers/iommu/intel/iommu.c
> +++ b/drivers/iommu/intel/iommu.c
> @@ -5165,13 +5165,10 @@ 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) - base);
> +		iommu_setup_dma_ops(dev, 0, U64_MAX);
>   	else
>   		set_dma_ops(dev, NULL);
>   }
>
Eric Auger June 22, 2021, 7:46 a.m. UTC | #2
Hi Jean,

On 6/18/21 5:20 PM, 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.
>
> The base and limit parameters are being phased out, because:
> * they are redundant for x86 callers. dma-iommu already reserves the
>   first page, and the upper limit is already in domain->geometry.
> * they can now be obtained from dev->dma_range_map on Arm.
> But removing them on Arm isn't completely straightforward so is left for
> future work. As an intermediate step, simplify the x86 callers by
> passing dummy limits.
>
> Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>

Eric
> ---
>  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 |  5 +----
>  5 files changed, 11 insertions(+), 14 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..6719f9efea09 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, dma_base + size - 1);
>  
>  #ifdef CONFIG_XEN
>  	if (xen_swiotlb_detect())
> diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c
> index 3ac42bbdefc6..216323fb27ef 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, 0, 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..2f7213f0e7a1 100644
> --- a/drivers/iommu/intel/iommu.c
> +++ b/drivers/iommu/intel/iommu.c
> @@ -5165,13 +5165,10 @@ 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) - base);
> +		iommu_setup_dma_ops(dev, 0, U64_MAX);
>  	else
>  		set_dma_ops(dev, NULL);
>  }
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..6719f9efea09 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, dma_base + size - 1);
 
 #ifdef CONFIG_XEN
 	if (xen_swiotlb_detect())
diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c
index 3ac42bbdefc6..216323fb27ef 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, 0, 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..2f7213f0e7a1 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -5165,13 +5165,10 @@  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) - base);
+		iommu_setup_dma_ops(dev, 0, U64_MAX);
 	else
 		set_dma_ops(dev, NULL);
 }