[PATCH 0/2] riscv: Support HAVE_ARCH_HUGE_VMAP and HAVE_ARCH_HUGE_VMALLOC

[PATCH 0/2] riscv: Support HAVE_ARCH_HUGE_VMAP and HAVE_ARCH_HUGE_VMALLOC

[Liu Shixin]

Since riscv64 has already support SATP_MODE_57 by default, it is time to
support more hugepage-related features. These two patches will enable
HAVE_ARCH_HUGE_VMAP and HAVE_ARCH_HUGE_VMALLOC.

Liu Shixin (2):
  riscv: Enable HAVE_ARCH_HUGE_VMAP for 64BIT
  riscv: Enable HAVE_ARCH_HUGE_VMALLOC for 64BIT

 .../features/vm/huge-vmap/arch-support.txt    |  2 +-
 arch/riscv/Kconfig                            |  2 +
 arch/riscv/include/asm/vmalloc.h              | 18 ++++
 arch/riscv/mm/Makefile                        |  1 +
 arch/riscv/mm/pgtable.c                       | 83 +++++++++++++++++++
 5 files changed, 105 insertions(+), 1 deletion(-)
 create mode 100644 arch/riscv/mm/pgtable.c

-- 
2.25.1

[PATCH 1/2] riscv: Enable HAVE_ARCH_HUGE_VMAP for 64BIT

[Liu Shixin]

This sets the HAVE_ARCH_HUGE_VMAP option, and defines the required
page table functions. With this feature, ioremap area will be mapped with
huge page granularity according to its actual size. This feature can be
disabled by kernel parameter "nohugeiomap".

Signed-off-by: Liu Shixin <liushixin2@huawei.com>
---
 .../features/vm/huge-vmap/arch-support.txt    |  2 +-
 arch/riscv/Kconfig                            |  1 +
 arch/riscv/include/asm/vmalloc.h              | 18 ++++
 arch/riscv/mm/Makefile                        |  1 +
 arch/riscv/mm/pgtable.c                       | 83 +++++++++++++++++++
 5 files changed, 104 insertions(+), 1 deletion(-)
 create mode 100644 arch/riscv/mm/pgtable.c

diff --git a/Documentation/features/vm/huge-vmap/arch-support.txt b/Documentation/features/vm/huge-vmap/arch-support.txt
index 13b4940e0c3a..7274a4b15bcc 100644
--- a/Documentation/features/vm/huge-vmap/arch-support.txt
+++ b/Documentation/features/vm/huge-vmap/arch-support.txt
@@ -21,7 +21,7 @@
     |    openrisc: | TODO |
     |      parisc: | TODO |
     |     powerpc: |  ok  |
-    |       riscv: | TODO |
+    |       riscv: |  ok  |
     |        s390: | TODO |
     |          sh: | TODO |
     |       sparc: | TODO |
diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index d557cc50295d..336b925570c0 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -70,6 +70,7 @@ config RISCV
 	select GENERIC_TIME_VSYSCALL if MMU && 64BIT
 	select GENERIC_VDSO_TIME_NS if HAVE_GENERIC_VDSO
 	select HAVE_ARCH_AUDITSYSCALL
+	select HAVE_ARCH_HUGE_VMAP if MMU && 64BIT && !XIP_KERNEL
 	select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL
 	select HAVE_ARCH_JUMP_LABEL_RELATIVE if !XIP_KERNEL
 	select HAVE_ARCH_KASAN if MMU && 64BIT
diff --git a/arch/riscv/include/asm/vmalloc.h b/arch/riscv/include/asm/vmalloc.h
index ff9abc00d139..48da5371f1e9 100644
--- a/arch/riscv/include/asm/vmalloc.h
+++ b/arch/riscv/include/asm/vmalloc.h
@@ -1,4 +1,22 @@
 #ifndef _ASM_RISCV_VMALLOC_H
 #define _ASM_RISCV_VMALLOC_H
 
+#ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
+
+#define IOREMAP_MAX_ORDER (PUD_SHIFT)
+
+#define arch_vmap_pud_supported arch_vmap_pud_supported
+static inline bool arch_vmap_pud_supported(pgprot_t prot)
+{
+	return true;
+}
+
+#define arch_vmap_pmd_supported arch_vmap_pmd_supported
+static inline bool arch_vmap_pmd_supported(pgprot_t prot)
+{
+	return true;
+}
+
+#endif
+
 #endif /* _ASM_RISCV_VMALLOC_H */
diff --git a/arch/riscv/mm/Makefile b/arch/riscv/mm/Makefile
index d76aabf4b94d..ce7f121ad2dc 100644
--- a/arch/riscv/mm/Makefile
+++ b/arch/riscv/mm/Makefile
@@ -13,6 +13,7 @@ obj-y += extable.o
 obj-$(CONFIG_MMU) += fault.o pageattr.o
 obj-y += cacheflush.o
 obj-y += context.o
+obj-y += pgtable.o
 
 ifeq ($(CONFIG_MMU),y)
 obj-$(CONFIG_SMP) += tlbflush.o
diff --git a/arch/riscv/mm/pgtable.c b/arch/riscv/mm/pgtable.c
new file mode 100644
index 000000000000..6645ead1a7c1
--- /dev/null
+++ b/arch/riscv/mm/pgtable.c
@@ -0,0 +1,83 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <asm/pgalloc.h>
+#include <linux/gfp.h>
+#include <linux/kernel.h>
+#include <linux/pgtable.h>
+
+#ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
+int p4d_set_huge(p4d_t *p4d, phys_addr_t addr, pgprot_t prot)
+{
+	return 0;
+}
+
+void p4d_clear_huge(p4d_t *p4d)
+{
+}
+
+int pud_set_huge(pud_t *pud, phys_addr_t phys, pgprot_t prot)
+{
+	pud_t new_pud = pfn_pud(__phys_to_pfn(phys), prot);
+
+	set_pud(pud, new_pud);
+	return 1;
+}
+
+int pud_clear_huge(pud_t *pud)
+{
+	if (!pud_leaf(READ_ONCE(*pud)))
+		return 0;
+	pud_clear(pud);
+	return 1;
+}
+
+int pud_free_pmd_page(pud_t *pud, unsigned long addr)
+{
+	pmd_t *pmd = pud_pgtable(*pud);
+	int i;
+
+	pud_clear(pud);
+
+	flush_tlb_kernel_range(addr, addr + PUD_SIZE);
+
+	for (i = 0; i < PTRS_PER_PMD; i++) {
+		if (!pmd_none(pmd[i])) {
+			pte_t *pte = (pte_t *)pmd_page_vaddr(pmd[i]);
+
+			pte_free_kernel(NULL, pte);
+		}
+	}
+
+	pmd_free(NULL, pmd);
+
+	return 1;
+}
+
+int pmd_set_huge(pmd_t *pmd, phys_addr_t phys, pgprot_t prot)
+{
+	pmd_t new_pmd = pfn_pmd(__phys_to_pfn(phys), prot);
+
+	set_pmd(pmd, new_pmd);
+	return 1;
+}
+
+int pmd_clear_huge(pmd_t *pmd)
+{
+	if (!pmd_leaf(READ_ONCE(*pmd)))
+		return 0;
+	pmd_clear(pmd);
+	return 1;
+}
+
+int pmd_free_pte_page(pmd_t *pmd, unsigned long addr)
+{
+	pte_t *pte = (pte_t *)pmd_page_vaddr(*pmd);
+
+	pmd_clear(pmd);
+
+	flush_tlb_kernel_range(addr, addr + PMD_SIZE);
+	pte_free_kernel(NULL, pte);
+	return 1;
+}
+
+#endif /* CONFIG_HAVE_ARCH_HUGE_VMAP */
-- 
2.25.1

[PATCH 2/2] riscv: Enable HAVE_ARCH_HUGE_VMALLOC for 64BIT

[Liu Shixin]

After we support HAVE_ARCH_HUGE_VMAP, we can now enbale HAVE_ARCH_HUGE_VMALLOC
too. This feature has been used in kvmalloc and alloc_large_system_hash
for now. This feature can be disabled by kernel parameters "nohugevmalloc".

Signed-off-by: Liu Shixin <liushixin2@huawei.com>
---
 arch/riscv/Kconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index 336b925570c0..d567dca3ae75 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -70,6 +70,7 @@ config RISCV
 	select GENERIC_TIME_VSYSCALL if MMU && 64BIT
 	select GENERIC_VDSO_TIME_NS if HAVE_GENERIC_VDSO
 	select HAVE_ARCH_AUDITSYSCALL
+	select HAVE_ARCH_HUGE_VMALLOC
 	select HAVE_ARCH_HUGE_VMAP if MMU && 64BIT && !XIP_KERNEL
 	select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL
 	select HAVE_ARCH_JUMP_LABEL_RELATIVE if !XIP_KERNEL
-- 
2.25.1

Re: [PATCH 0/2] riscv: Support HAVE_ARCH_HUGE_VMAP and HAVE_ARCH_HUGE_VMALLOC

[Conor Dooley]

On Thu, Sep 15, 2022 at 02:50:25PM +0800, Liu Shixin wrote:
> Since riscv64 has already support SATP_MODE_57 by default, it is time to
> support more hugepage-related features. These two patches will enable
> HAVE_ARCH_HUGE_VMAP and HAVE_ARCH_HUGE_VMALLOC.
> 
> Liu Shixin (2):
>   riscv: Enable HAVE_ARCH_HUGE_VMAP for 64BIT
>   riscv: Enable HAVE_ARCH_HUGE_VMALLOC for 64BIT

Hey Liu Shixin,
As I'm sure you saw earlier today LKP randconfig testing of linux-next*
found a problem with your patchset, but looks like it should be
trivially fixable.

Thanks,
Conor.

* I accidentally added it to my dt-for-next branch, from which it is now
dropped.

> 
>  .../features/vm/huge-vmap/arch-support.txt    |  2 +-
>  arch/riscv/Kconfig                            |  2 +
>  arch/riscv/include/asm/vmalloc.h              | 18 ++++
>  arch/riscv/mm/Makefile                        |  1 +
>  arch/riscv/mm/pgtable.c                       | 83 +++++++++++++++++++
>  5 files changed, 105 insertions(+), 1 deletion(-)
>  create mode 100644 arch/riscv/mm/pgtable.c
> 
> -- 
> 2.25.1
> 
> 
> _______________________________________________
> linux-riscv mailing list
> linux-riscv@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-riscv

Re: [PATCH 2/2] riscv: Enable HAVE_ARCH_HUGE_VMALLOC for 64BIT

[Kefeng Wang]

On 2022/9/15 14:50, Liu Shixin wrote:
> After we support HAVE_ARCH_HUGE_VMAP, we can now enbale HAVE_ARCH_HUGE_VMALLOC
> too. This feature has been used in kvmalloc and alloc_large_system_hash
> for now. This feature can be disabled by kernel parameters "nohugevmalloc".
>
> Signed-off-by: Liu Shixin <liushixin2@huawei.com>
> ---
>   arch/riscv/Kconfig | 1 +
>   1 file changed, 1 insertion(+)
>
> diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
> index 336b925570c0..d567dca3ae75 100644
> --- a/arch/riscv/Kconfig
> +++ b/arch/riscv/Kconfig
> @@ -70,6 +70,7 @@ config RISCV
>   	select GENERIC_TIME_VSYSCALL if MMU && 64BIT
>   	select GENERIC_VDSO_TIME_NS if HAVE_GENERIC_VDSO
>   	select HAVE_ARCH_AUDITSYSCALL
> +	select HAVE_ARCH_HUGE_VMALLOC

should be "select HAVE_ARCH_HUGE_VMALLOC if HAVE_ARCH_HUGE_VMAP"

this could also fix the lkp build issue.

>   	select HAVE_ARCH_HUGE_VMAP if MMU && 64BIT && !XIP_KERNEL
>   	select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL
>   	select HAVE_ARCH_JUMP_LABEL_RELATIVE if !XIP_KERNEL