/**
* free_pgd_slow:释放pgd项
*/
void free_pgd_slow(struct mm_struct *mm, pgd_t *pgd)
{
pmd_t *pmd;
pgtable_t pte;
if (!pgd)
return;
/* pgd is always present and good */
pmd = pmd_off(pgd, 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:
free_pages((unsigned long) pgd, 2);
}
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);
}
void free_pgd_slow(pgd_t *pgd)
{
pmd_t *pmd;
pte_t *pte;
if (!pgd)
return;
/* pgd is always present and good */
pmd = (pmd_t *)pgd;
if (pmd_none(*pmd))
goto free;
if (pmd_bad(*pmd)) {
pmd_ERROR(*pmd);
pmd_clear(pmd);
goto free;
}
pte = pte_offset(pmd, 0);
pmd_clear(pmd);
pte_free(pte);
pmd_free(pmd);
free:
free_pages((unsigned long) pgd, 2);
}
void pgd_free(struct mm_struct *mm, pgd_t *pgd_base)
{
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, 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:
#if defined(CONFIG_SYNO_ARMADA_ARCH)
#ifdef CONFIG_ARM_LPAE
/*
* Free modules/pkmap or identity pmd tables.
*/
for (pgd = pgd_base; pgd < pgd_base + PTRS_PER_PGD; pgd++) {
if (pgd_none_or_clear_bad(pgd))
continue;
if (pgd_val(*pgd) & L_PGD_SWAPPER)
continue;
pud = pud_offset(pgd, 0);
if (pud_none_or_clear_bad(pud))
continue;
pmd = pmd_offset(pud, 0);
pud_clear(pud);
pmd_free(mm, pmd);
pgd_clear(pgd);
pud_free(mm, pud);
}
#endif
__pgd_free(pgd_base);
#elif defined(CONFIG_SYNO_COMCERTO)
free_pages((unsigned long) pgd_base, get_order(16384));
#else
free_pages((unsigned long) pgd_base, 2);
#endif
}
/* This is only called when we are critically out of memory
* (and fail to get a page in pte_free_tlb).
*/
void pte_free_now(struct page *ptepage)
{
pte_freelist_forced_free++;
smp_call_function(pte_free_smp_sync, NULL, 0, 1);
pte_free(ptepage);
}
static void pte_free_rcu_callback(void *arg)
{
struct pte_freelist_batch *batch = arg;
unsigned int i;
for (i = 0; i < batch->index; i++)
pte_free(batch->pages[i]);
free_page((unsigned long)batch);
}
void pgd_free(struct mm_struct *mm, pgd_t *pgd_base)
{
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, 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);
mm_dec_nr_ptes(mm);
no_pmd:
pud_clear(pud);
pmd_free(mm, pmd);
mm_dec_nr_pmds(mm);
no_pud:
pgd_clear(pgd);
pud_free(mm, pud);
no_pgd:
#ifdef CONFIG_ARM_LPAE
/*
* Free modules/pkmap or identity pmd tables.
*/
for (pgd = pgd_base; pgd < pgd_base + PTRS_PER_PGD; pgd++) {
if (pgd_none_or_clear_bad(pgd))
continue;
if (pgd_val(*pgd) & L_PGD_SWAPPER)
continue;
pud = pud_offset(pgd, 0);
if (pud_none_or_clear_bad(pud))
continue;
pmd = pmd_offset(pud, 0);
pud_clear(pud);
pmd_free(mm, pmd);
mm_dec_nr_pmds(mm);
pgd_clear(pgd);
pud_free(mm, pud);
}
#endif
__pgd_free(pgd_base);
}
static void pte_free_rcu_callback(struct rcu_head *head)
{
struct pte_freelist_batch *batch =
container_of(head, struct pte_freelist_batch, rcu);
unsigned int i;
for (i = 0; i < batch->index; i++)
pte_free(batch->pages[i]);
free_page((unsigned long)batch);
}
void arch_release_hugepage(struct page *page)
{
pte_t *ptep;
if (MACHINE_HAS_HPAGE)
return;
ptep = (pte_t *) page[1].index;
if (!ptep)
return;
pte_free(&init_mm, ptep);
page[1].index = 0;
}
/*
* Note: this doesn't free the actual pages themselves. That
* has been handled earlier when unmapping all the memory regions.
*/
static inline void free_one_pmd(pmd_t * dir)
{
pte_t * pte;
if (pmd_none(*dir))
return;
if (pmd_bad(*dir)) {
pmd_ERROR(*dir);
pmd_clear(dir);
return;
}
pte = pte_offset(dir, 0);
pmd_clear(dir);
pte_free(pte);
}
/*
* Note: this doesn't free the actual pages themselves. That
* has been handled earlier when unmapping all the memory regions.
*/
static inline void free_one_pmd(pmd_t * dir)
{
pte_t * pte;
if (pmd_none(*dir))
return;
if (pmd_bad(*dir)) {
printk("free_one_pmd: bad directory entry %08lx\n", pmd_val(*dir));
pmd_clear(dir);
return;
}
pte = pte_offset(dir, 0);
pmd_clear(dir);
pte_free(pte);
}
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);
}
/* This is only called when we are critically out of memory
* (and fail to get a page in pte_free_tlb).
*/
static void pgtable_free_now(struct page *pte)
{
smp_call_function(pte_free_smp_sync, NULL, 0, 1);
pte_free(pte);
}
