diff options
Diffstat (limited to 'arch/arm64/mm/pageattr.c')
| -rw-r--r-- | arch/arm64/mm/pageattr.c | 125 |
1 files changed, 93 insertions, 32 deletions
diff --git a/arch/arm64/mm/pageattr.c b/arch/arm64/mm/pageattr.c index 04d4a8f676db..5135f2d66958 100644 --- a/arch/arm64/mm/pageattr.c +++ b/arch/arm64/mm/pageattr.c @@ -8,6 +8,7 @@ #include <linux/mem_encrypt.h> #include <linux/sched.h> #include <linux/vmalloc.h> +#include <linux/pagewalk.h> #include <asm/cacheflush.h> #include <asm/pgtable-prot.h> @@ -20,7 +21,66 @@ struct page_change_data { pgprot_t clear_mask; }; -bool rodata_full __ro_after_init = IS_ENABLED(CONFIG_RODATA_FULL_DEFAULT_ENABLED); +static ptdesc_t set_pageattr_masks(ptdesc_t val, struct mm_walk *walk) +{ + struct page_change_data *masks = walk->private; + + val &= ~(pgprot_val(masks->clear_mask)); + val |= (pgprot_val(masks->set_mask)); + + return val; +} + +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_sect(val)) { + if (WARN_ON_ONCE((next - addr) != PUD_SIZE)) + return -EINVAL; + val = __pud(set_pageattr_masks(pud_val(val), walk)); + set_pud(pud, val); + walk->action = ACTION_CONTINUE; + } + + 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_sect(val)) { + if (WARN_ON_ONCE((next - addr) != PMD_SIZE)) + return -EINVAL; + val = __pmd(set_pageattr_masks(pmd_val(val), walk)); + set_pmd(pmd, val); + walk->action = ACTION_CONTINUE; + } + + 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 const struct mm_walk_ops pageattr_ops = { + .pud_entry = pageattr_pud_entry, + .pmd_entry = pageattr_pmd_entry, + .pte_entry = pageattr_pte_entry, +}; + +bool rodata_full __ro_after_init = true; bool can_set_direct_map(void) { @@ -37,32 +97,39 @@ bool can_set_direct_map(void) arm64_kfence_can_set_direct_map() || is_realm_world(); } -static int change_page_range(pte_t *ptep, unsigned long addr, void *data) +static int update_range_prot(unsigned long start, unsigned long size, + pgprot_t set_mask, pgprot_t clear_mask) { - struct page_change_data *cdata = data; - pte_t pte = __ptep_get(ptep); + struct page_change_data data; + int ret; - pte = clear_pte_bit(pte, cdata->clear_mask); - pte = set_pte_bit(pte, cdata->set_mask); + data.set_mask = set_mask; + data.clear_mask = clear_mask; - __set_pte(ptep, pte); - return 0; + ret = split_kernel_leaf_mapping(start, start + size); + if (WARN_ON_ONCE(ret)) + return ret; + + arch_enter_lazy_mmu_mode(); + + /* + * The caller must ensure that the range we are operating on does not + * partially overlap a block mapping, or a cont mapping. Any such case + * must be eliminated by splitting the mapping. + */ + ret = walk_kernel_page_table_range_lockless(start, start + size, + &pageattr_ops, NULL, &data); + arch_leave_lazy_mmu_mode(); + + return ret; } -/* - * This function assumes that the range is mapped with PAGE_SIZE pages. - */ static int __change_memory_common(unsigned long start, unsigned long size, - pgprot_t set_mask, pgprot_t clear_mask) + pgprot_t set_mask, pgprot_t clear_mask) { - struct page_change_data data; int ret; - data.set_mask = set_mask; - data.clear_mask = clear_mask; - - ret = apply_to_page_range(&init_mm, start, size, change_page_range, - &data); + ret = update_range_prot(start, size, set_mask, clear_mask); /* * If the memory is being made valid without changing any other bits @@ -174,32 +241,26 @@ int set_memory_valid(unsigned long addr, int numpages, int enable) int set_direct_map_invalid_noflush(struct page *page) { - struct page_change_data data = { - .set_mask = __pgprot(0), - .clear_mask = __pgprot(PTE_VALID), - }; + pgprot_t clear_mask = __pgprot(PTE_VALID); + pgprot_t set_mask = __pgprot(0); if (!can_set_direct_map()) return 0; - return apply_to_page_range(&init_mm, - (unsigned long)page_address(page), - PAGE_SIZE, change_page_range, &data); + return update_range_prot((unsigned long)page_address(page), + PAGE_SIZE, set_mask, clear_mask); } int set_direct_map_default_noflush(struct page *page) { - struct page_change_data data = { - .set_mask = __pgprot(PTE_VALID | PTE_WRITE), - .clear_mask = __pgprot(PTE_RDONLY), - }; + pgprot_t set_mask = __pgprot(PTE_VALID | PTE_WRITE); + pgprot_t clear_mask = __pgprot(PTE_RDONLY); if (!can_set_direct_map()) return 0; - return apply_to_page_range(&init_mm, - (unsigned long)page_address(page), - PAGE_SIZE, change_page_range, &data); + return update_range_prot((unsigned long)page_address(page), + PAGE_SIZE, set_mask, clear_mask); } static int __set_memory_enc_dec(unsigned long addr, |