diff options
Diffstat (limited to 'arch/loongarch/mm/pageattr.c')
| -rw-r--r-- | arch/loongarch/mm/pageattr.c | 218 |
1 files changed, 218 insertions, 0 deletions
diff --git a/arch/loongarch/mm/pageattr.c b/arch/loongarch/mm/pageattr.c new file mode 100644 index 000000000000..ffd8d76021d4 --- /dev/null +++ b/arch/loongarch/mm/pageattr.c @@ -0,0 +1,218 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2024 Loongson Technology Corporation Limited + */ + +#include <linux/pagewalk.h> +#include <linux/pgtable.h> +#include <asm/set_memory.h> +#include <asm/tlbflush.h> + +struct pageattr_masks { + pgprot_t set_mask; + pgprot_t clear_mask; +}; + +static unsigned long set_pageattr_masks(unsigned long val, struct mm_walk *walk) +{ + unsigned long new_val = val; + struct pageattr_masks *masks = walk->private; + + new_val &= ~(pgprot_val(masks->clear_mask)); + new_val |= (pgprot_val(masks->set_mask)); + + return new_val; +} + +static int pageattr_pgd_entry(pgd_t *pgd, unsigned long addr, + unsigned long next, struct mm_walk *walk) +{ + pgd_t val = pgdp_get(pgd); + + if (pgd_leaf(val)) { + val = __pgd(set_pageattr_masks(pgd_val(val), walk)); + set_pgd(pgd, val); + } + + return 0; +} + +static int pageattr_p4d_entry(p4d_t *p4d, unsigned long addr, + unsigned long next, struct mm_walk *walk) +{ + p4d_t val = p4dp_get(p4d); + + if (p4d_leaf(val)) { + val = __p4d(set_pageattr_masks(p4d_val(val), walk)); + set_p4d(p4d, val); + } + + return 0; +} + +static int pageattr_pud_entry(pud_t *pud, unsigned long addr, + unsigned long next, struct mm_walk *walk) +{ + pud_t val = pudp_get(pud); + + if (pud_leaf(val)) { + val = __pud(set_pageattr_masks(pud_val(val), walk)); + set_pud(pud, val); + } + + return 0; +} + +static int pageattr_pmd_entry(pmd_t *pmd, unsigned long addr, + unsigned long next, struct mm_walk *walk) +{ + pmd_t val = pmdp_get(pmd); + + if (pmd_leaf(val)) { + val = __pmd(set_pageattr_masks(pmd_val(val), walk)); + set_pmd(pmd, val); + } + + return 0; +} + +static int pageattr_pte_entry(pte_t *pte, unsigned long addr, + unsigned long next, struct mm_walk *walk) +{ + pte_t val = ptep_get(pte); + + val = __pte(set_pageattr_masks(pte_val(val), walk)); + set_pte(pte, val); + + return 0; +} + +static int pageattr_pte_hole(unsigned long addr, unsigned long next, + int depth, struct mm_walk *walk) +{ + return 0; +} + +static const struct mm_walk_ops pageattr_ops = { + .pgd_entry = pageattr_pgd_entry, + .p4d_entry = pageattr_p4d_entry, + .pud_entry = pageattr_pud_entry, + .pmd_entry = pageattr_pmd_entry, + .pte_entry = pageattr_pte_entry, + .pte_hole = pageattr_pte_hole, + .walk_lock = PGWALK_RDLOCK, +}; + +static int __set_memory(unsigned long addr, int numpages, pgprot_t set_mask, pgprot_t clear_mask) +{ + int ret; + unsigned long start = addr; + unsigned long end = start + PAGE_SIZE * numpages; + struct pageattr_masks masks = { + .set_mask = set_mask, + .clear_mask = clear_mask + }; + + if (!numpages) + return 0; + + mmap_write_lock(&init_mm); + ret = walk_page_range_novma(&init_mm, start, end, &pageattr_ops, NULL, &masks); + mmap_write_unlock(&init_mm); + + flush_tlb_kernel_range(start, end); + + return ret; +} + +int set_memory_x(unsigned long addr, int numpages) +{ + if (addr < vm_map_base) + return 0; + + return __set_memory(addr, numpages, __pgprot(0), __pgprot(_PAGE_NO_EXEC)); +} + +int set_memory_nx(unsigned long addr, int numpages) +{ + if (addr < vm_map_base) + return 0; + + return __set_memory(addr, numpages, __pgprot(_PAGE_NO_EXEC), __pgprot(0)); +} + +int set_memory_ro(unsigned long addr, int numpages) +{ + if (addr < vm_map_base) + return 0; + + return __set_memory(addr, numpages, __pgprot(0), __pgprot(_PAGE_WRITE | _PAGE_DIRTY)); +} + +int set_memory_rw(unsigned long addr, int numpages) +{ + if (addr < vm_map_base) + return 0; + + return __set_memory(addr, numpages, __pgprot(_PAGE_WRITE | _PAGE_DIRTY), __pgprot(0)); +} + +bool kernel_page_present(struct page *page) +{ + pgd_t *pgd; + p4d_t *p4d; + pud_t *pud; + pmd_t *pmd; + pte_t *pte; + unsigned long addr = (unsigned long)page_address(page); + + if (addr < vm_map_base) + return true; + + pgd = pgd_offset_k(addr); + if (pgd_none(pgdp_get(pgd))) + return false; + if (pgd_leaf(pgdp_get(pgd))) + return true; + + p4d = p4d_offset(pgd, addr); + if (p4d_none(p4dp_get(p4d))) + return false; + if (p4d_leaf(p4dp_get(p4d))) + return true; + + pud = pud_offset(p4d, addr); + if (pud_none(pudp_get(pud))) + return false; + if (pud_leaf(pudp_get(pud))) + return true; + + pmd = pmd_offset(pud, addr); + if (pmd_none(pmdp_get(pmd))) + return false; + if (pmd_leaf(pmdp_get(pmd))) + return true; + + pte = pte_offset_kernel(pmd, addr); + return pte_present(ptep_get(pte)); +} + +int set_direct_map_default_noflush(struct page *page) +{ + unsigned long addr = (unsigned long)page_address(page); + + if (addr < vm_map_base) + return 0; + + return __set_memory(addr, 1, PAGE_KERNEL, __pgprot(0)); +} + +int set_direct_map_invalid_noflush(struct page *page) +{ + unsigned long addr = (unsigned long)page_address(page); + + if (addr < vm_map_base) + return 0; + + return __set_memory(addr, 1, __pgprot(0), __pgprot(_PAGE_PRESENT | _PAGE_VALID)); +} |