riscv: Enable HAVE_ARCH_HUGE_VMAP for 64BIT

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>
Reviewed-by: Björn Töpel <bjorn@kernel.org>
Tested-by: Björn Töpel <bjorn@kernel.org>
Link: https://lore.kernel.org/r/20221012120038.1034354-2-liushixin2@huawei.com
[Palmer: minor formatting]
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
This commit is contained in:
Liu Shixin 2022-10-12 20:00:37 +08:00 committed by Palmer Dabbelt
parent 3558927fc2
commit 310f541a02
No known key found for this signature in database
GPG Key ID: 2E1319F35FBB1889
5 changed files with 104 additions and 1 deletions

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@ -21,7 +21,7 @@
| openrisc: | TODO |
| parisc: | TODO |
| powerpc: | ok |
| riscv: | TODO |
| riscv: | ok |
| s390: | TODO |
| sh: | TODO |
| sparc: | TODO |

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@ -72,6 +72,7 @@ config RISCV
select GENERIC_VDSO_TIME_NS if HAVE_GENERIC_VDSO
select HARDIRQS_SW_RESEND
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

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@ -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 */

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@ -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

83
arch/riscv/mm/pgtable.c Normal file
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@ -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 */