diff options
Diffstat (limited to 'arch/arm64/mm/mmu.c')
| -rw-r--r-- | arch/arm64/mm/mmu.c | 46 |
1 files changed, 24 insertions, 22 deletions
diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index 8080c9f489c3..9498c15b847b 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -67,6 +67,24 @@ static pte_t bm_pte[PTRS_PER_PTE] __page_aligned_bss; static pmd_t bm_pmd[PTRS_PER_PMD] __page_aligned_bss __maybe_unused; static pud_t bm_pud[PTRS_PER_PUD] __page_aligned_bss __maybe_unused; +static DEFINE_SPINLOCK(swapper_pgdir_lock); + +void set_swapper_pgd(pgd_t *pgdp, pgd_t pgd) +{ + pgd_t *fixmap_pgdp; + + spin_lock(&swapper_pgdir_lock); + fixmap_pgdp = pgd_set_fixmap(__pa_symbol(pgdp)); + WRITE_ONCE(*fixmap_pgdp, pgd); + /* + * We need dsb(ishst) here to ensure the page-table-walker sees + * our new entry before set_p?d() returns. The fixmap's + * flush_tlb_kernel_range() via clear_fixmap() does this for us. + */ + pgd_clear_fixmap(); + spin_unlock(&swapper_pgdir_lock); +} + pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn, unsigned long size, pgprot_t vma_prot) { @@ -629,34 +647,18 @@ static void __init map_kernel(pgd_t *pgdp) */ void __init paging_init(void) { - phys_addr_t pgd_phys = early_pgtable_alloc(); - pgd_t *pgdp = pgd_set_fixmap(pgd_phys); + pgd_t *pgdp = pgd_set_fixmap(__pa_symbol(swapper_pg_dir)); map_kernel(pgdp); map_mem(pgdp); - /* - * We want to reuse the original swapper_pg_dir so we don't have to - * communicate the new address to non-coherent secondaries in - * secondary_entry, and so cpu_switch_mm can generate the address with - * adrp+add rather than a load from some global variable. - * - * To do this we need to go via a temporary pgd. - */ - cpu_replace_ttbr1(__va(pgd_phys)); - memcpy(swapper_pg_dir, pgdp, PGD_SIZE); - cpu_replace_ttbr1(lm_alias(swapper_pg_dir)); - pgd_clear_fixmap(); - memblock_free(pgd_phys, PAGE_SIZE); - /* - * We only reuse the PGD from the swapper_pg_dir, not the pud + pmd - * allocated with it. - */ - memblock_free(__pa_symbol(swapper_pg_dir) + PAGE_SIZE, - __pa_symbol(swapper_pg_end) - __pa_symbol(swapper_pg_dir) - - PAGE_SIZE); + cpu_replace_ttbr1(lm_alias(swapper_pg_dir)); + init_mm.pgd = swapper_pg_dir; + + memblock_free(__pa_symbol(init_pg_dir), + __pa_symbol(init_pg_end) - __pa_symbol(init_pg_dir)); } /* |