[v5,2/8] iommu/dma: Introduce generic helper to retrieve RMR info

Message ID 20210524110222.2212-3-shameerali.kolothum.thodi@huawei.com
State New
Headers show
Series
  • ACPI/IORT: Support for IORT RMR node
Related show

Commit Message

Shameerali Kolothum Thodi May 24, 2021, 11:02 a.m.
Reserved Memory Regions(RMR) associated with an IOMMU can be
described through ACPI IORT tables in systems with devices
that require a unity mapping or bypass for those
regions.

Introduce a generic interface so that IOMMU drivers can retrieve
and set up necessary mappings. Also introduce a union to struct
iommu_resv_region to hold any firmware specific data(eg:RMR
specific info).

Signed-off-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>

---
 drivers/iommu/dma-iommu.c | 29 +++++++++++++++++++++++++++++
 include/linux/dma-iommu.h | 13 +++++++++++++
 include/linux/iommu.h     | 10 ++++++++++
 3 files changed, 52 insertions(+)

-- 
2.17.1

Comments

kernel test robot May 24, 2021, 3:35 p.m. | #1
Hi Shameer,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on iommu/next]
[also build test WARNING on pm/linux-next arm64/for-next/core linus/master v5.13-rc3 next-20210524]
[cannot apply to xlnx/master arm/for-next soc/for-next]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/Shameer-Kolothum/ACPI-IORT-Support-for-IORT-RMR-node/20210524-190633
base:   https://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu.git next
config: x86_64-randconfig-a013-20210524 (attached as .config)
compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project 93d1e5822ed64abd777eb94ea9899e96c4c39fbe)
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # install x86_64 cross compiling tool for clang build
        # apt-get install binutils-x86-64-linux-gnu
        # https://github.com/0day-ci/linux/commit/2c046e03beb7d64e0f7182d01a7dc63dce79c882
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Shameer-Kolothum/ACPI-IORT-Support-for-IORT-RMR-node/20210524-190633
        git checkout 2c046e03beb7d64e0f7182d01a7dc63dce79c882
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=x86_64 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All warnings (new ones prefixed by >>):

   In file included from drivers/vfio/vfio_iommu_type1.c:41:
>> include/linux/dma-iommu.h:90:5: warning: no previous prototype for function 'iommu_dma_get_rmrs' [-Wmissing-prototypes]

   int iommu_dma_get_rmrs(struct fwnode_handle *iommu, struct list_head *list)
       ^
   include/linux/dma-iommu.h:90:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
   int iommu_dma_get_rmrs(struct fwnode_handle *iommu, struct list_head *list)
   ^
   static 
>> include/linux/dma-iommu.h:95:6: warning: no previous prototype for function 'iommu_dma_put_rmrs' [-Wmissing-prototypes]

   void iommu_dma_put_rmrs(struct fwnode_handle *iommu, struct list_head *list)
        ^
   include/linux/dma-iommu.h:95:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
   void iommu_dma_put_rmrs(struct fwnode_handle *iommu, struct list_head *list)
   ^
   static 
   2 warnings generated.


vim +/iommu_dma_get_rmrs +90 include/linux/dma-iommu.h

    89	
  > 90	int iommu_dma_get_rmrs(struct fwnode_handle *iommu, struct list_head *list)

    91	{
    92		return -ENODEV;
    93	}
    94	
  > 95	void iommu_dma_put_rmrs(struct fwnode_handle *iommu, struct list_head *list)

    96	{
    97	}
    98	

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org

Patch

diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c
index 7bcdd1205535..229ec65d98be 100644
--- a/drivers/iommu/dma-iommu.c
+++ b/drivers/iommu/dma-iommu.c
@@ -174,6 +174,35 @@  void iommu_put_dma_cookie(struct iommu_domain *domain)
 }
 EXPORT_SYMBOL(iommu_put_dma_cookie);
 
+/**
+ *
+ * iommu_dma_get_rmrs - Retrieve Reserved Memory Regions(RMRs) associated
+ *                      with a given IOMMU
+ * @iommu_fwnode: fwnode associated with IOMMU
+ * @list: RMR list to be populated
+ *
+ */
+int iommu_dma_get_rmrs(struct fwnode_handle *iommu_fwnode,
+		       struct list_head *list)
+{
+	return -EINVAL;
+}
+EXPORT_SYMBOL(iommu_dma_get_rmrs);
+
+/**
+ *
+ * iommu_dma_put_rmrs - Release Reserved Memory Regions(RMRs) associated
+ *                      with a given IOMMU
+ * @iommu_fwnode: fwnode associated with IOMMU
+ * @list: RMR list
+ *
+ */
+void iommu_dma_put_rmrs(struct fwnode_handle *iommu_fwnode,
+			struct list_head *list)
+{
+}
+EXPORT_SYMBOL(iommu_dma_put_rmrs);
+
 /**
  * iommu_dma_get_resv_regions - Reserved region driver helper
  * @dev: Device from iommu_get_resv_regions()
diff --git a/include/linux/dma-iommu.h b/include/linux/dma-iommu.h
index 6e75a2d689b4..a83e6c09444c 100644
--- a/include/linux/dma-iommu.h
+++ b/include/linux/dma-iommu.h
@@ -42,12 +42,16 @@  void iommu_dma_free_cpu_cached_iovas(unsigned int cpu,
 
 extern bool iommu_dma_forcedac;
 
+int iommu_dma_get_rmrs(struct fwnode_handle *iommu, struct list_head *list);
+void iommu_dma_put_rmrs(struct fwnode_handle *iommu, struct list_head *list);
+
 #else /* CONFIG_IOMMU_DMA */
 
 struct iommu_domain;
 struct msi_desc;
 struct msi_msg;
 struct device;
+struct fwnode_handle;
 
 static inline void iommu_setup_dma_ops(struct device *dev, u64 dma_base,
 		u64 size)
@@ -83,5 +87,14 @@  static inline void iommu_dma_get_resv_regions(struct device *dev, struct list_he
 {
 }
 
+int iommu_dma_get_rmrs(struct fwnode_handle *iommu, struct list_head *list)
+{
+	return -ENODEV;
+}
+
+void iommu_dma_put_rmrs(struct fwnode_handle *iommu, struct list_head *list)
+{
+}
+
 #endif	/* CONFIG_IOMMU_DMA */
 #endif	/* __DMA_IOMMU_H */
diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index 32d448050bf7..856a1736c744 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -114,6 +114,12 @@  enum iommu_resv_type {
 	IOMMU_RESV_SW_MSI,
 };
 
+struct iommu_iort_rmr_data {
+#define IOMMU_RMR_REMAP_PERMITTED	(1 << 0)
+	u32 flags;
+	u32 sid;	/* Stream Id associated with RMR entry */
+};
+
 /**
  * struct iommu_resv_region - descriptor for a reserved memory region
  * @list: Linked list pointers
@@ -121,6 +127,7 @@  enum iommu_resv_type {
  * @length: Length of the region in bytes
  * @prot: IOMMU Protection flags (READ/WRITE/...)
  * @type: Type of the reserved region
+ * @rmr: ACPI IORT RMR specific data
  */
 struct iommu_resv_region {
 	struct list_head	list;
@@ -128,6 +135,9 @@  struct iommu_resv_region {
 	size_t			length;
 	int			prot;
 	enum iommu_resv_type	type;
+	union {
+		struct iommu_iort_rmr_data rmr;
+	} fw_data;
 };
 
 /**