void free_pgd_slow(struct mm_struct *mm, pgd_t *pgd)
{
unsigned long flags;
pmd_t *pmd;
pgtable_t pte;
if (!pgd)
return;
/* pgd is always present and good */
pmd = pmd_off(pgd + pgd_index(fcse_va_to_mva(mm, 0)), 0);
if (pmd_none(*pmd))
goto free;
if (pmd_bad(*pmd)) {
pmd_ERROR(*pmd);
pmd_clear(pmd);
goto free;
}
pte = pmd_pgtable(*pmd);
pmd_clear(pmd);
pte_free(mm, pte);
pmd_free(mm, pmd);
free:
pgd_list_lock(flags);
pgd_list_del(pgd);
pgd_list_unlock(flags);
free_pages((unsigned long) pgd, 2);
}
/*
* need to get a 16k page for level 1
*/
pgd_t *get_pgd_slow(struct mm_struct *mm)
{
pgd_t *new_pgd, *init_pgd;
pmd_t *new_pmd, *init_pmd;
pte_t *new_pte, *init_pte;
unsigned long flags;
new_pgd = (pgd_t *)__get_free_pages(GFP_KERNEL, 2);
if (!new_pgd)
goto no_pgd;
memset(new_pgd, 0, FIRST_KERNEL_PGD_NR * sizeof(pgd_t));
/*
* Copy over the kernel and IO PGD entries
*/
init_pgd = pgd_offset_k(0);
pgd_list_lock(flags);
memcpy(new_pgd + FIRST_KERNEL_PGD_NR, init_pgd + FIRST_KERNEL_PGD_NR,
(PTRS_PER_PGD - FIRST_KERNEL_PGD_NR) * sizeof(pgd_t));
pgd_list_add(new_pgd);
pgd_list_unlock(flags);
clean_dcache_area(new_pgd, PTRS_PER_PGD * sizeof(pgd_t));
if (!vectors_high()) {
#ifdef CONFIG_ARM_FCSE
/* FCSE does not work without high vectors. */
BUG();
#endif /* CONFIG_ARM_FCSE */
/*
* On ARM, first page must always be allocated since it
* contains the machine vectors.
*/
new_pmd = pmd_alloc(mm, new_pgd, 0);
if (!new_pmd)
goto no_pmd;
new_pte = pte_alloc_map(mm, new_pmd, 0);
if (!new_pte)
goto no_pte;
init_pmd = pmd_offset(init_pgd, 0);
init_pte = pte_offset_map_nested(init_pmd, 0);
set_pte_ext(new_pte, *init_pte, 0);
pte_unmap_nested(init_pte);
pte_unmap(new_pte);
}
return new_pgd;
no_pte:
pmd_free(mm, new_pmd);
no_pmd:
free_pages((unsigned long)new_pgd, 2);
no_pgd:
return NULL;
}
void pgd_free(struct mm_struct *mm, pgd_t *pgd_base)
{
unsigned long flags;
pgd_t *pgd;
pud_t *pud;
pmd_t *pmd;
pgtable_t pte;
if (!pgd_base)
return;
pgd = pgd_base + pgd_index(0);
if (pgd_none_or_clear_bad(pgd))
goto no_pgd;
pud = pud_offset(pgd + pgd_index(fcse_va_to_mva(mm, 0)), 0);
if (pud_none_or_clear_bad(pud))
goto no_pud;
pmd = pmd_offset(pud, 0);
if (pmd_none_or_clear_bad(pmd))
goto no_pmd;
pte = pmd_pgtable(*pmd);
pmd_clear(pmd);
pte_free(mm, pte);
no_pmd:
pud_clear(pud);
pmd_free(mm, pmd);
no_pud:
pgd_clear(pgd);
pud_free(mm, pud);
no_pgd:
pgd_list_lock(flags);
pgd_list_del(pgd);
pgd_list_unlock(flags);
free_pages((unsigned long) pgd_base, 2);
}