diff options
| author | Zeng Chi <zengchi@kylinos.cn> | 2026-09-21 18:24:42 +0800 |
|---|---|---|
| committer | Sean Christopherson <seanjc@google.com> | 2026-09-22 08:36:16 -0700 |
| commit | 119e9db233ad0f4cbd4cfb9f9385a7bca378b37d (patch) | |
| tree | 660d50d4139cb750fbde1ae3432452c20726c99d /arch/mips/mm/pgtable-32.c | |
| download | linux-stable-119e9db233ad0f4cbd4cfb9f9385a7bca378b37d.tar.gz linux-stable-119e9db233ad0f4cbd4cfb9f9385a7bca378b37d.zip | |
KVM: Don't pre-reserve xarray entries when storing empty/NULL attributesgrafted
Skip the xarray reservation loop when clearing all memory attributes, as
storing NULL only erases the entry and never needs to allocate, so no
reservation (and no cleanup of a failed one) is required in that case.
Suggested-by: Sean Christopherson <seanjc@google.com>
Cc: David Ballesteros <davimaba.v@proton.me>
Signed-off-by: Zeng Chi <zengchi@kylinos.cn>
Link: https://patch.msgid.link/20260921102442.1232375-1-zeng_chi911@163.com
[sean: split to separate patch]
Signed-off-by: Sean Christopherson <seanjc@google.com>
Diffstat (limited to 'arch/mips/mm/pgtable-32.c')
| -rw-r--r-- | arch/mips/mm/pgtable-32.c | 79 |
1 files changed, 79 insertions, 0 deletions
diff --git a/arch/mips/mm/pgtable-32.c b/arch/mips/mm/pgtable-32.c new file mode 100644 index 000000000..e2cf2166d --- /dev/null +++ b/arch/mips/mm/pgtable-32.c @@ -0,0 +1,79 @@ +/* + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + * + * Copyright (C) 2003 by Ralf Baechle + */ +#include <linux/init.h> +#include <linux/mm.h> +#include <linux/memblock.h> +#include <linux/highmem.h> +#include <asm/fixmap.h> +#include <asm/pgalloc.h> +#include <asm/tlbflush.h> + +void pgd_init(void *addr) +{ + unsigned long *p = (unsigned long *)addr; + int i; + + for (i = 0; i < USER_PTRS_PER_PGD; i+=8) { + p[i + 0] = (unsigned long) invalid_pte_table; + p[i + 1] = (unsigned long) invalid_pte_table; + p[i + 2] = (unsigned long) invalid_pte_table; + p[i + 3] = (unsigned long) invalid_pte_table; + p[i + 4] = (unsigned long) invalid_pte_table; + p[i + 5] = (unsigned long) invalid_pte_table; + p[i + 6] = (unsigned long) invalid_pte_table; + p[i + 7] = (unsigned long) invalid_pte_table; + } +} + +#if defined(CONFIG_TRANSPARENT_HUGEPAGE) +void set_pmd_at(struct mm_struct *mm, unsigned long addr, + pmd_t *pmdp, pmd_t pmd) +{ + *pmdp = pmd; +} +#endif /* defined(CONFIG_TRANSPARENT_HUGEPAGE) */ + +void __init pagetable_init(void) +{ + unsigned long vaddr; + pgd_t *pgd_base; +#ifdef CONFIG_HIGHMEM + pgd_t *pgd; + p4d_t *p4d; + pud_t *pud; + pmd_t *pmd; + pte_t *pte; +#endif + + /* Initialize the entire pgd. */ + pgd_init(swapper_pg_dir); + pgd_init(&swapper_pg_dir[USER_PTRS_PER_PGD]); + + pgd_base = swapper_pg_dir; + + /* + * Fixed mappings: + */ + vaddr = __fix_to_virt(__end_of_fixed_addresses - 1); + fixrange_init(vaddr & PMD_MASK, vaddr + FIXADDR_SIZE, pgd_base); + +#ifdef CONFIG_HIGHMEM + /* + * Permanent kmaps: + */ + vaddr = PKMAP_BASE; + fixrange_init(vaddr & PMD_MASK, vaddr + PAGE_SIZE*LAST_PKMAP, pgd_base); + + pgd = swapper_pg_dir + pgd_index(vaddr); + p4d = p4d_offset(pgd, vaddr); + pud = pud_offset(p4d, vaddr); + pmd = pmd_offset(pud, vaddr); + pte = pte_offset_kernel(pmd, vaddr); + pkmap_page_table = pte; +#endif +} |