diff mbox

[5/7] iommu/dma: add support for non-strict mode

Message ID 1527752569-18020-6-git-send-email-thunder.leizhen@huawei.com (mailing list archive)
State New, archived
Headers show

Commit Message

Leizhen (ThunderTown) May 31, 2018, 7:42 a.m. UTC 
1. Save the related domain pointer in struct iommu_dma_cookie, make iovad
   capable call domain->ops->flush_iotlb_all to flush TLB.
2. Define a new iommu capable: IOMMU_CAP_NON_STRICT, which used to indicate
   that the iommu domain support non-strict mode.
3. During the iommu domain initialization phase, call capable() to check
   whether it support non-strcit mode. If so, call init_iova_flush_queue
   to register iovad->flush_cb callback.
4. All unmap(contains iova-free) APIs will finally invoke __iommu_dma_unmap
   -->iommu_dma_free_iova. Use iovad->flush_cb to check whether its related
   iommu support non-strict mode or not, and call IOMMU_DOMAIN_IS_STRICT to
   make sure the IOMMU_DOMAIN_UNMANAGED domain always follow strict mode.

Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
---
 drivers/iommu/dma-iommu.c | 29 ++++++++++++++++++++++++++---
 include/linux/iommu.h     |  3 +++
 2 files changed, 29 insertions(+), 3 deletions(-)

Comments

Robin Murphy May 31, 2018, 1:04 p.m. UTC | #1 
On 31/05/18 08:42, Zhen Lei wrote:
> 1. Save the related domain pointer in struct iommu_dma_cookie, make iovad
>     capable call domain->ops->flush_iotlb_all to flush TLB.
> 2. Define a new iommu capable: IOMMU_CAP_NON_STRICT, which used to indicate
>     that the iommu domain support non-strict mode.
> 3. During the iommu domain initialization phase, call capable() to check
>     whether it support non-strcit mode. If so, call init_iova_flush_queue
>     to register iovad->flush_cb callback.
> 4. All unmap(contains iova-free) APIs will finally invoke __iommu_dma_unmap
>     -->iommu_dma_free_iova. Use iovad->flush_cb to check whether its related
>     iommu support non-strict mode or not, and call IOMMU_DOMAIN_IS_STRICT to
>     make sure the IOMMU_DOMAIN_UNMANAGED domain always follow strict mode.

Once again, this is a whole load of complexity for a property which 
could just be statically encoded at allocation, e.g. in the cookie type.

> Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
> ---
>   drivers/iommu/dma-iommu.c | 29 ++++++++++++++++++++++++++---
>   include/linux/iommu.h     |  3 +++
>   2 files changed, 29 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c
> index 4e885f7..2e116d9 100644
> --- a/drivers/iommu/dma-iommu.c
> +++ b/drivers/iommu/dma-iommu.c
> @@ -55,6 +55,7 @@ struct iommu_dma_cookie {
>   	};
>   	struct list_head		msi_page_list;
>   	spinlock_t			msi_lock;
> +	struct iommu_domain		*domain;
>   };
>   
>   static inline size_t cookie_msi_granule(struct iommu_dma_cookie *cookie)
> @@ -64,7 +65,8 @@ static inline size_t cookie_msi_granule(struct iommu_dma_cookie *cookie)
>   	return PAGE_SIZE;
>   }
>   
> -static struct iommu_dma_cookie *cookie_alloc(enum iommu_dma_cookie_type type)
> +static struct iommu_dma_cookie *cookie_alloc(struct iommu_domain *domain,
> +					     enum iommu_dma_cookie_type type)
>   {
>   	struct iommu_dma_cookie *cookie;
>   
> @@ -73,6 +75,7 @@ static struct iommu_dma_cookie *cookie_alloc(enum iommu_dma_cookie_type type)
>   		spin_lock_init(&cookie->msi_lock);
>   		INIT_LIST_HEAD(&cookie->msi_page_list);
>   		cookie->type = type;
> +		cookie->domain = domain;
>   	}
>   	return cookie;
>   }
> @@ -94,7 +97,7 @@ int iommu_get_dma_cookie(struct iommu_domain *domain)
>   	if (domain->iova_cookie)
>   		return -EEXIST;
>   
> -	domain->iova_cookie = cookie_alloc(IOMMU_DMA_IOVA_COOKIE);
> +	domain->iova_cookie = cookie_alloc(domain, IOMMU_DMA_IOVA_COOKIE);
>   	if (!domain->iova_cookie)
>   		return -ENOMEM;
>   
> @@ -124,7 +127,7 @@ int iommu_get_msi_cookie(struct iommu_domain *domain, dma_addr_t base)
>   	if (domain->iova_cookie)
>   		return -EEXIST;
>   
> -	cookie = cookie_alloc(IOMMU_DMA_MSI_COOKIE);
> +	cookie = cookie_alloc(domain, IOMMU_DMA_MSI_COOKIE);
>   	if (!cookie)
>   		return -ENOMEM;
>   
> @@ -261,6 +264,17 @@ static int iova_reserve_iommu_regions(struct device *dev,
>   	return ret;
>   }
>   
> +static void iova_flush_iotlb_all(struct iova_domain *iovad)

iommu_dma_flush...

> +{
> +	struct iommu_dma_cookie *cookie;
> +	struct iommu_domain *domain;
> +
> +	cookie = container_of(iovad, struct iommu_dma_cookie, iovad);
> +	domain = cookie->domain;
> +
> +	domain->ops->flush_iotlb_all(domain);
> +}
> +
>   /**
>    * iommu_dma_init_domain - Initialise a DMA mapping domain
>    * @domain: IOMMU domain previously prepared by iommu_get_dma_cookie()
> @@ -276,6 +290,7 @@ static int iova_reserve_iommu_regions(struct device *dev,
>   int iommu_dma_init_domain(struct iommu_domain *domain, dma_addr_t base,
>   		u64 size, struct device *dev)
>   {
> +	const struct iommu_ops *ops = domain->ops;
>   	struct iommu_dma_cookie *cookie = domain->iova_cookie;
>   	struct iova_domain *iovad = &cookie->iovad;
>   	unsigned long order, base_pfn, end_pfn;
> @@ -313,6 +328,11 @@ int iommu_dma_init_domain(struct iommu_domain *domain, dma_addr_t base,
>   
>   	init_iova_domain(iovad, 1UL << order, base_pfn);
>   
> +	if (ops->capable && ops->capable(IOMMU_CAP_NON_STRICT)) {
> +		BUG_ON(!ops->flush_iotlb_all);
> +		init_iova_flush_queue(iovad, iova_flush_iotlb_all, NULL);
> +	}
> +
>   	return iova_reserve_iommu_regions(dev, domain);
>   }
>   EXPORT_SYMBOL(iommu_dma_init_domain);
> @@ -392,6 +412,9 @@ static void iommu_dma_free_iova(struct iommu_dma_cookie *cookie,
>   	/* The MSI case is only ever cleaning up its most recent allocation */
>   	if (cookie->type == IOMMU_DMA_MSI_COOKIE)
>   		cookie->msi_iova -= size;
> +	else if (!IOMMU_DOMAIN_IS_STRICT(cookie->domain) && iovad->flush_cb)
> +		queue_iova(iovad, iova_pfn(iovad, iova),
> +				size >> iova_shift(iovad), 0);
>   	else
>   		free_iova_fast(iovad, iova_pfn(iovad, iova),
>   				size >> iova_shift(iovad));
> diff --git a/include/linux/iommu.h b/include/linux/iommu.h
> index 39b3150..01ff569 100644
> --- a/include/linux/iommu.h
> +++ b/include/linux/iommu.h
> @@ -87,6 +87,8 @@ struct iommu_domain_geometry {
>   				 __IOMMU_DOMAIN_DMA_API)
>   
>   #define IOMMU_STRICT		1
> +#define IOMMU_DOMAIN_IS_STRICT(domain)	\
> +		(domain->type == IOMMU_DOMAIN_UNMANAGED)
>   
>   struct iommu_domain {
>   	unsigned type;
> @@ -103,6 +105,7 @@ enum iommu_cap {
>   					   transactions */
>   	IOMMU_CAP_INTR_REMAP,		/* IOMMU supports interrupt isolation */
>   	IOMMU_CAP_NOEXEC,		/* IOMMU_NOEXEC flag */
> +	IOMMU_CAP_NON_STRICT,		/* IOMMU supports non-strict mode */

This isn't a property of the IOMMU, it depends purely on the driver 
implementation. I think it also doesn't matter anyway - if a caller asks 
for lazy unmapping on their domain but the IOMMU driver just does strict 
unmaps anyway because that's all it supports, there's no actual harm done.

Robin.

>   };
>   
>   /*
>
kernel test robot June 1, 2018, 5:51 p.m. UTC | #2 
Hi Zhen,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on linus/master]
[also build test WARNING on v4.17-rc7 next-20180601]
[cannot apply to iommu/next]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url:    https://github.com/0day-ci/linux/commits/Zhen-Lei/add-non-strict-mode-support-for-arm-smmu-v3/20180602-000418
config: x86_64-randconfig-x008-201821 (attached as .config)
compiler: gcc-7 (Debian 7.3.0-16) 7.3.0
reproduce:
        # save the attached .config to linux build tree
        make ARCH=x86_64 

All warnings (new ones prefixed by >>):

   drivers//iommu/amd_iommu.c: In function 'amd_iommu_capable':
>> drivers//iommu/amd_iommu.c:3053:2: warning: enumeration value 'IOMMU_CAP_NON_STRICT' not handled in switch [-Wswitch]
     switch (cap) {
     ^~~~~~

vim +/IOMMU_CAP_NON_STRICT +3053 drivers//iommu/amd_iommu.c

645c4c8d arch/x86/kernel/amd_iommu.c Joerg Roedel 2008-12-02  3050  
ab636481 drivers/iommu/amd_iommu.c   Joerg Roedel 2014-09-05  3051  static bool amd_iommu_capable(enum iommu_cap cap)
dbb9fd86 arch/x86/kernel/amd_iommu.c Sheng Yang   2009-03-18  3052  {
80a506b8 arch/x86/kernel/amd_iommu.c Joerg Roedel 2010-07-27 @3053  	switch (cap) {
80a506b8 arch/x86/kernel/amd_iommu.c Joerg Roedel 2010-07-27  3054  	case IOMMU_CAP_CACHE_COHERENCY:
ab636481 drivers/iommu/amd_iommu.c   Joerg Roedel 2014-09-05  3055  		return true;
bdddadcb drivers/iommu/amd_iommu.c   Joerg Roedel 2012-07-02  3056  	case IOMMU_CAP_INTR_REMAP:
ab636481 drivers/iommu/amd_iommu.c   Joerg Roedel 2014-09-05  3057  		return (irq_remapping_enabled == 1);
cfdeec22 drivers/iommu/amd_iommu.c   Will Deacon  2014-10-27  3058  	case IOMMU_CAP_NOEXEC:
cfdeec22 drivers/iommu/amd_iommu.c   Will Deacon  2014-10-27  3059  		return false;
80a506b8 arch/x86/kernel/amd_iommu.c Joerg Roedel 2010-07-27  3060  	}
80a506b8 arch/x86/kernel/amd_iommu.c Joerg Roedel 2010-07-27  3061  
ab636481 drivers/iommu/amd_iommu.c   Joerg Roedel 2014-09-05  3062  	return false;
dbb9fd86 arch/x86/kernel/amd_iommu.c Sheng Yang   2009-03-18  3063  }
dbb9fd86 arch/x86/kernel/amd_iommu.c Sheng Yang   2009-03-18  3064  

:::::: The code at line 3053 was first introduced by commit
:::::: 80a506b8fdcfa868bb53eb740f928217d0966fc1 x86/amd-iommu: Export cache-coherency capability

:::::: TO: Joerg Roedel <joerg.roedel@amd.com>
:::::: CC: Joerg Roedel <joerg.roedel@amd.com>

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation
Leizhen (ThunderTown) June 4, 2018, 12:04 p.m. UTC | #3 
On 2018/5/31 21:04, Robin Murphy wrote:
> On 31/05/18 08:42, Zhen Lei wrote:
>> 1. Save the related domain pointer in struct iommu_dma_cookie, make iovad
>>     capable call domain->ops->flush_iotlb_all to flush TLB.
>> 2. Define a new iommu capable: IOMMU_CAP_NON_STRICT, which used to indicate
>>     that the iommu domain support non-strict mode.
>> 3. During the iommu domain initialization phase, call capable() to check
>>     whether it support non-strcit mode. If so, call init_iova_flush_queue
>>     to register iovad->flush_cb callback.
>> 4. All unmap(contains iova-free) APIs will finally invoke __iommu_dma_unmap
>>     -->iommu_dma_free_iova. Use iovad->flush_cb to check whether its related
>>     iommu support non-strict mode or not, and call IOMMU_DOMAIN_IS_STRICT to
>>     make sure the IOMMU_DOMAIN_UNMANAGED domain always follow strict mode.
> 
> Once again, this is a whole load of complexity for a property which could just be statically encoded at allocation, e.g. in the cookie type.
That's right. Pass domain to the static function iommu_dma_free_iova will be better.

> 
>> Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
>> ---
>>   drivers/iommu/dma-iommu.c | 29 ++++++++++++++++++++++++++---
>>   include/linux/iommu.h     |  3 +++
>>   2 files changed, 29 insertions(+), 3 deletions(-)
>>
>> diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c
>> index 4e885f7..2e116d9 100644
>> --- a/drivers/iommu/dma-iommu.c
>> +++ b/drivers/iommu/dma-iommu.c
>> @@ -55,6 +55,7 @@ struct iommu_dma_cookie {
>>       };
>>       struct list_head        msi_page_list;
>>       spinlock_t            msi_lock;
>> +    struct iommu_domain        *domain;
>>   };
>>     static inline size_t cookie_msi_granule(struct iommu_dma_cookie *cookie)
>> @@ -64,7 +65,8 @@ static inline size_t cookie_msi_granule(struct iommu_dma_cookie *cookie)
>>       return PAGE_SIZE;
>>   }
>>   -static struct iommu_dma_cookie *cookie_alloc(enum iommu_dma_cookie_type type)
>> +static struct iommu_dma_cookie *cookie_alloc(struct iommu_domain *domain,
>> +                         enum iommu_dma_cookie_type type)
>>   {
>>       struct iommu_dma_cookie *cookie;
>>   @@ -73,6 +75,7 @@ static struct iommu_dma_cookie *cookie_alloc(enum iommu_dma_cookie_type type)
>>           spin_lock_init(&cookie->msi_lock);
>>           INIT_LIST_HEAD(&cookie->msi_page_list);
>>           cookie->type = type;
>> +        cookie->domain = domain;
>>       }
>>       return cookie;
>>   }
>> @@ -94,7 +97,7 @@ int iommu_get_dma_cookie(struct iommu_domain *domain)
>>       if (domain->iova_cookie)
>>           return -EEXIST;
>>   -    domain->iova_cookie = cookie_alloc(IOMMU_DMA_IOVA_COOKIE);
>> +    domain->iova_cookie = cookie_alloc(domain, IOMMU_DMA_IOVA_COOKIE);
>>       if (!domain->iova_cookie)
>>           return -ENOMEM;
>>   @@ -124,7 +127,7 @@ int iommu_get_msi_cookie(struct iommu_domain *domain, dma_addr_t base)
>>       if (domain->iova_cookie)
>>           return -EEXIST;
>>   -    cookie = cookie_alloc(IOMMU_DMA_MSI_COOKIE);
>> +    cookie = cookie_alloc(domain, IOMMU_DMA_MSI_COOKIE);
>>       if (!cookie)
>>           return -ENOMEM;
>>   @@ -261,6 +264,17 @@ static int iova_reserve_iommu_regions(struct device *dev,
>>       return ret;
>>   }
>>   +static void iova_flush_iotlb_all(struct iova_domain *iovad)
> 
> iommu_dma_flush...
OK

> 
>> +{
>> +    struct iommu_dma_cookie *cookie;
>> +    struct iommu_domain *domain;
>> +
>> +    cookie = container_of(iovad, struct iommu_dma_cookie, iovad);
>> +    domain = cookie->domain;
>> +
>> +    domain->ops->flush_iotlb_all(domain);
>> +}
>> +
>>   /**
>>    * iommu_dma_init_domain - Initialise a DMA mapping domain
>>    * @domain: IOMMU domain previously prepared by iommu_get_dma_cookie()
>> @@ -276,6 +290,7 @@ static int iova_reserve_iommu_regions(struct device *dev,
>>   int iommu_dma_init_domain(struct iommu_domain *domain, dma_addr_t base,
>>           u64 size, struct device *dev)
>>   {
>> +    const struct iommu_ops *ops = domain->ops;
>>       struct iommu_dma_cookie *cookie = domain->iova_cookie;
>>       struct iova_domain *iovad = &cookie->iovad;
>>       unsigned long order, base_pfn, end_pfn;
>> @@ -313,6 +328,11 @@ int iommu_dma_init_domain(struct iommu_domain *domain, dma_addr_t base,
>>         init_iova_domain(iovad, 1UL << order, base_pfn);
>>   +    if (ops->capable && ops->capable(IOMMU_CAP_NON_STRICT)) {
>> +        BUG_ON(!ops->flush_iotlb_all);
>> +        init_iova_flush_queue(iovad, iova_flush_iotlb_all, NULL);
>> +    }
>> +
>>       return iova_reserve_iommu_regions(dev, domain);
>>   }
>>   EXPORT_SYMBOL(iommu_dma_init_domain);
>> @@ -392,6 +412,9 @@ static void iommu_dma_free_iova(struct iommu_dma_cookie *cookie,
>>       /* The MSI case is only ever cleaning up its most recent allocation */
>>       if (cookie->type == IOMMU_DMA_MSI_COOKIE)
>>           cookie->msi_iova -= size;
>> +    else if (!IOMMU_DOMAIN_IS_STRICT(cookie->domain) && iovad->flush_cb)
>> +        queue_iova(iovad, iova_pfn(iovad, iova),
>> +                size >> iova_shift(iovad), 0);
>>       else
>>           free_iova_fast(iovad, iova_pfn(iovad, iova),
>>                   size >> iova_shift(iovad));
>> diff --git a/include/linux/iommu.h b/include/linux/iommu.h
>> index 39b3150..01ff569 100644
>> --- a/include/linux/iommu.h
>> +++ b/include/linux/iommu.h
>> @@ -87,6 +87,8 @@ struct iommu_domain_geometry {
>>                    __IOMMU_DOMAIN_DMA_API)
>>     #define IOMMU_STRICT        1
>> +#define IOMMU_DOMAIN_IS_STRICT(domain)    \
>> +        (domain->type == IOMMU_DOMAIN_UNMANAGED)
>>     struct iommu_domain {
>>       unsigned type;
>> @@ -103,6 +105,7 @@ enum iommu_cap {
>>                          transactions */
>>       IOMMU_CAP_INTR_REMAP,        /* IOMMU supports interrupt isolation */
>>       IOMMU_CAP_NOEXEC,        /* IOMMU_NOEXEC flag */
>> +    IOMMU_CAP_NON_STRICT,        /* IOMMU supports non-strict mode */
> 
> This isn't a property of the IOMMU, it depends purely on the driver implementation. I think it also doesn't matter anyway - if a caller asks for lazy unmapping on their domain but the IOMMU driver just does strict unmaps anyway because that's all it supports, there's no actual harm done.
> 
> Robin.
> 
>>   };
>>     /*
>>
> 
> .
>
Leizhen (ThunderTown) June 4, 2018, 12:19 p.m. UTC | #4 
On 2018/6/2 1:51, kbuild test robot wrote:
> Hi Zhen,
> 
> Thank you for the patch! Perhaps something to improve:
> 
> [auto build test WARNING on linus/master]
> [also build test WARNING on v4.17-rc7 next-20180601]
> [cannot apply to iommu/next]
> [if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
> 
> url:    https://github.com/0day-ci/linux/commits/Zhen-Lei/add-non-strict-mode-support-for-arm-smmu-v3/20180602-000418
> config: x86_64-randconfig-x008-201821 (attached as .config)
> compiler: gcc-7 (Debian 7.3.0-16) 7.3.0
> reproduce:
>         # save the attached .config to linux build tree
>         make ARCH=x86_64 
> 
> All warnings (new ones prefixed by >>):
> 
>    drivers//iommu/amd_iommu.c: In function 'amd_iommu_capable':
>>> drivers//iommu/amd_iommu.c:3053:2: warning: enumeration value 'IOMMU_CAP_NON_STRICT' not handled in switch [-Wswitch]
>      switch (cap) {
>      ^~~~~~
> 
> vim +/IOMMU_CAP_NON_STRICT +3053 drivers//iommu/amd_iommu.c
> 
> 645c4c8d arch/x86/kernel/amd_iommu.c Joerg Roedel 2008-12-02  3050  
> ab636481 drivers/iommu/amd_iommu.c   Joerg Roedel 2014-09-05  3051  static bool amd_iommu_capable(enum iommu_cap cap)
> dbb9fd86 arch/x86/kernel/amd_iommu.c Sheng Yang   2009-03-18  3052  {
> 80a506b8 arch/x86/kernel/amd_iommu.c Joerg Roedel 2010-07-27 @3053  	switch (cap) {
> 80a506b8 arch/x86/kernel/amd_iommu.c Joerg Roedel 2010-07-27  3054  	case IOMMU_CAP_CACHE_COHERENCY:
> ab636481 drivers/iommu/amd_iommu.c   Joerg Roedel 2014-09-05  3055  		return true;
> bdddadcb drivers/iommu/amd_iommu.c   Joerg Roedel 2012-07-02  3056  	case IOMMU_CAP_INTR_REMAP:
> ab636481 drivers/iommu/amd_iommu.c   Joerg Roedel 2014-09-05  3057  		return (irq_remapping_enabled == 1);
> cfdeec22 drivers/iommu/amd_iommu.c   Will Deacon  2014-10-27  3058  	case IOMMU_CAP_NOEXEC:
It seems that it's better to change this to 'default'.

> cfdeec22 drivers/iommu/amd_iommu.c   Will Deacon  2014-10-27  3059  		return false;
> 80a506b8 arch/x86/kernel/amd_iommu.c Joerg Roedel 2010-07-27  3060  	}
> 80a506b8 arch/x86/kernel/amd_iommu.c Joerg Roedel 2010-07-27  3061  
> ab636481 drivers/iommu/amd_iommu.c   Joerg Roedel 2014-09-05  3062  	return false;
> dbb9fd86 arch/x86/kernel/amd_iommu.c Sheng Yang   2009-03-18  3063  }
> dbb9fd86 arch/x86/kernel/amd_iommu.c Sheng Yang   2009-03-18  3064  
> 
> :::::: The code at line 3053 was first introduced by commit
> :::::: 80a506b8fdcfa868bb53eb740f928217d0966fc1 x86/amd-iommu: Export cache-coherency capability
> 
> :::::: TO: Joerg Roedel <joerg.roedel@amd.com>
> :::::: CC: Joerg Roedel <joerg.roedel@amd.com>
> 
> ---
> 0-DAY kernel test infrastructure                Open Source Technology Center
> https://lists.01.org/pipermail/kbuild-all                   Intel Corporation
>
diff mbox

Patch

diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c
index 4e885f7..2e116d9 100644
--- a/drivers/iommu/dma-iommu.c
+++ b/drivers/iommu/dma-iommu.c
@@ -55,6 +55,7 @@  struct iommu_dma_cookie {
 	};
 	struct list_head		msi_page_list;
 	spinlock_t			msi_lock;
+	struct iommu_domain		*domain;
 };
 
 static inline size_t cookie_msi_granule(struct iommu_dma_cookie *cookie)
@@ -64,7 +65,8 @@  static inline size_t cookie_msi_granule(struct iommu_dma_cookie *cookie)
 	return PAGE_SIZE;
 }
 
-static struct iommu_dma_cookie *cookie_alloc(enum iommu_dma_cookie_type type)
+static struct iommu_dma_cookie *cookie_alloc(struct iommu_domain *domain,
+					     enum iommu_dma_cookie_type type)
 {
 	struct iommu_dma_cookie *cookie;
 
@@ -73,6 +75,7 @@  static struct iommu_dma_cookie *cookie_alloc(enum iommu_dma_cookie_type type)
 		spin_lock_init(&cookie->msi_lock);
 		INIT_LIST_HEAD(&cookie->msi_page_list);
 		cookie->type = type;
+		cookie->domain = domain;
 	}
 	return cookie;
 }
@@ -94,7 +97,7 @@  int iommu_get_dma_cookie(struct iommu_domain *domain)
 	if (domain->iova_cookie)
 		return -EEXIST;
 
-	domain->iova_cookie = cookie_alloc(IOMMU_DMA_IOVA_COOKIE);
+	domain->iova_cookie = cookie_alloc(domain, IOMMU_DMA_IOVA_COOKIE);
 	if (!domain->iova_cookie)
 		return -ENOMEM;
 
@@ -124,7 +127,7 @@  int iommu_get_msi_cookie(struct iommu_domain *domain, dma_addr_t base)
 	if (domain->iova_cookie)
 		return -EEXIST;
 
-	cookie = cookie_alloc(IOMMU_DMA_MSI_COOKIE);
+	cookie = cookie_alloc(domain, IOMMU_DMA_MSI_COOKIE);
 	if (!cookie)
 		return -ENOMEM;
 
@@ -261,6 +264,17 @@  static int iova_reserve_iommu_regions(struct device *dev,
 	return ret;
 }
 
+static void iova_flush_iotlb_all(struct iova_domain *iovad)
+{
+	struct iommu_dma_cookie *cookie;
+	struct iommu_domain *domain;
+
+	cookie = container_of(iovad, struct iommu_dma_cookie, iovad);
+	domain = cookie->domain;
+
+	domain->ops->flush_iotlb_all(domain);
+}
+
 /**
  * iommu_dma_init_domain - Initialise a DMA mapping domain
  * @domain: IOMMU domain previously prepared by iommu_get_dma_cookie()
@@ -276,6 +290,7 @@  static int iova_reserve_iommu_regions(struct device *dev,
 int iommu_dma_init_domain(struct iommu_domain *domain, dma_addr_t base,
 		u64 size, struct device *dev)
 {
+	const struct iommu_ops *ops = domain->ops;
 	struct iommu_dma_cookie *cookie = domain->iova_cookie;
 	struct iova_domain *iovad = &cookie->iovad;
 	unsigned long order, base_pfn, end_pfn;
@@ -313,6 +328,11 @@  int iommu_dma_init_domain(struct iommu_domain *domain, dma_addr_t base,
 
 	init_iova_domain(iovad, 1UL << order, base_pfn);
 
+	if (ops->capable && ops->capable(IOMMU_CAP_NON_STRICT)) {
+		BUG_ON(!ops->flush_iotlb_all);
+		init_iova_flush_queue(iovad, iova_flush_iotlb_all, NULL);
+	}
+
 	return iova_reserve_iommu_regions(dev, domain);
 }
 EXPORT_SYMBOL(iommu_dma_init_domain);
@@ -392,6 +412,9 @@  static void iommu_dma_free_iova(struct iommu_dma_cookie *cookie,
 	/* The MSI case is only ever cleaning up its most recent allocation */
 	if (cookie->type == IOMMU_DMA_MSI_COOKIE)
 		cookie->msi_iova -= size;
+	else if (!IOMMU_DOMAIN_IS_STRICT(cookie->domain) && iovad->flush_cb)
+		queue_iova(iovad, iova_pfn(iovad, iova),
+				size >> iova_shift(iovad), 0);
 	else
 		free_iova_fast(iovad, iova_pfn(iovad, iova),
 				size >> iova_shift(iovad));
diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index 39b3150..01ff569 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -87,6 +87,8 @@  struct iommu_domain_geometry {
 				 __IOMMU_DOMAIN_DMA_API)
 
 #define IOMMU_STRICT		1
+#define IOMMU_DOMAIN_IS_STRICT(domain)	\
+		(domain->type == IOMMU_DOMAIN_UNMANAGED)
 
 struct iommu_domain {
 	unsigned type;
@@ -103,6 +105,7 @@  enum iommu_cap {
 					   transactions */
 	IOMMU_CAP_INTR_REMAP,		/* IOMMU supports interrupt isolation */
 	IOMMU_CAP_NOEXEC,		/* IOMMU_NOEXEC flag */
+	IOMMU_CAP_NON_STRICT,		/* IOMMU supports non-strict mode */
 };
 
 /*