Re: [PATCH OLK-6.6 1/5] driver/svm: support SVSP feature, interface definition

driver/svm: 这个标题是不是要改下

在 2024/2/22 21:25, Yuan Can 写道:

From: Zhou Guanghui zhouguanghui1@huawei.com

ascend inclusion category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/I931MI CVE: NA

---

In the SVA scenario, the master device of the SMMU can access the address space of the process by the operation of binding process. The page table of the process is shared by the MMU and SMMU, In this case, if some addrss range cannot be accessed through the MMU, access to this address range needs to be isolated from the process page table.

If the default domain of the SMMU is used, the isolation can be achieved. However, the address space created by default domain do not like the address space of the process which can be shared by multiple SMMUs.

Therefore, we add a shadow virtual space of process. This address space is used only by the SMMU.

Signed-off-by: Zhou Guanghui zhouguanghui1@huawei.com

arch/arm64/Kconfig | 15 +++++++++++++++ kernel/fork.c | 1 + mm/mmap.c | 1 + 3 files changed, 17 insertions(+)

diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 67bc2ad13453..3e84b2572827 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -2455,6 +2455,21 @@ config DMI However, even with this option, the resultant kernel should continue to boot on existing non-UEFI platforms.

+config ASCEND_SVSP

• bool "Enable support for SVSP"

• default n

• depends on ARM_SMMU_V3_SVA

• help

•  SVSP means Shadow Virtual Space of Process, which is an IO space used for
  

•  master device of SMMU.
  

•  This space is only used for the master device, since the target address
  

•  after traslation by MMU is not an accessible physical address, but can
  

•  accessible by SMMU.
  

•  Therefore, in the sva scenario, an svsp is created for each target process
  

•  address space.
  

• endmenu # "Boot options"

  config COMPAT

diff --git a/kernel/fork.c b/kernel/fork.c index 00e5886c9e04..735bc670b49e 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -1373,6 +1373,7 @@ struct mm_struct *mm_alloc(void) memset(mm, 0, sizeof(*mm)); return mm_init(mm, current, current_user_ns()); } +EXPORT_SYMBOL_GPL(mm_alloc);

static inline void __mmput(struct mm_struct *mm) { diff --git a/mm/mmap.c b/mm/mmap.c index 21d1fc39bf21..5d78ebaeed60 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -2684,6 +2684,7 @@ int do_munmap(struct mm_struct *mm, unsigned long start, size_t len,

return do_vmi_munmap(&vmi, mm, start, len, uf, false); } +EXPORT_SYMBOL(do_munmap);

static unsigned long __mmap_region(struct mm_struct *mm, struct file *file, unsigned long addr,