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

Message ID 1527752569-18020-6-git-send-email-thunder.leizhen@huawei.com
State New
Headers show
Series
  • [1/7] iommu/dma: fix trival coding style mistake
Related show

Commit Message

Zhen Lei May 31, 2018, 7:42 a.m.
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(-)

-- 
1.8.3


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Comments

kbuild test robot June 1, 2018, 5:51 p.m. | #1
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
Zhen Lei June 4, 2018, 12:04 p.m. | #2
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.

> 

>>   };

>>     /*

>>

> 

> .

> 


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Zhen Lei June 4, 2018, 12:19 p.m. | #3
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

> 


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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 */
 };
 
 /*