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![Heiko Carstens](/assets/img/avatar_default.png)
Use CRST_ALLOC_ORDER to make it more obvious what the order means, and also to be consistent with other code, e.g. the vmemmap code. Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
714 lines
20 KiB
C
714 lines
20 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/*
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* Page table allocation functions
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*
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* Copyright IBM Corp. 2016
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* Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
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*/
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#include <linux/sysctl.h>
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#include <linux/slab.h>
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#include <linux/mm.h>
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#include <asm/mmu_context.h>
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#include <asm/pgalloc.h>
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#include <asm/gmap.h>
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#include <asm/tlb.h>
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#include <asm/tlbflush.h>
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#ifdef CONFIG_PGSTE
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int page_table_allocate_pgste = 0;
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EXPORT_SYMBOL(page_table_allocate_pgste);
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static struct ctl_table page_table_sysctl[] = {
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{
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.procname = "allocate_pgste",
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.data = &page_table_allocate_pgste,
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.maxlen = sizeof(int),
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.mode = S_IRUGO | S_IWUSR,
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.proc_handler = proc_dointvec_minmax,
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.extra1 = SYSCTL_ZERO,
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.extra2 = SYSCTL_ONE,
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},
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{ }
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};
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static struct ctl_table page_table_sysctl_dir[] = {
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{
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.procname = "vm",
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.maxlen = 0,
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.mode = 0555,
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.child = page_table_sysctl,
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},
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{ }
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};
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static int __init page_table_register_sysctl(void)
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{
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return register_sysctl_table(page_table_sysctl_dir) ? 0 : -ENOMEM;
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}
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__initcall(page_table_register_sysctl);
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#endif /* CONFIG_PGSTE */
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unsigned long *crst_table_alloc(struct mm_struct *mm)
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{
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struct page *page = alloc_pages(GFP_KERNEL, CRST_ALLOC_ORDER);
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if (!page)
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return NULL;
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arch_set_page_dat(page, CRST_ALLOC_ORDER);
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return (unsigned long *) page_to_virt(page);
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}
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void crst_table_free(struct mm_struct *mm, unsigned long *table)
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{
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free_pages((unsigned long)table, CRST_ALLOC_ORDER);
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}
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static void __crst_table_upgrade(void *arg)
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{
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struct mm_struct *mm = arg;
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/* change all active ASCEs to avoid the creation of new TLBs */
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if (current->active_mm == mm) {
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S390_lowcore.user_asce = mm->context.asce;
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__ctl_load(S390_lowcore.user_asce, 7, 7);
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}
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__tlb_flush_local();
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}
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int crst_table_upgrade(struct mm_struct *mm, unsigned long end)
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{
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unsigned long *pgd = NULL, *p4d = NULL, *__pgd;
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unsigned long asce_limit = mm->context.asce_limit;
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/* upgrade should only happen from 3 to 4, 3 to 5, or 4 to 5 levels */
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VM_BUG_ON(asce_limit < _REGION2_SIZE);
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if (end <= asce_limit)
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return 0;
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if (asce_limit == _REGION2_SIZE) {
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p4d = crst_table_alloc(mm);
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if (unlikely(!p4d))
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goto err_p4d;
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crst_table_init(p4d, _REGION2_ENTRY_EMPTY);
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}
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if (end > _REGION1_SIZE) {
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pgd = crst_table_alloc(mm);
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if (unlikely(!pgd))
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goto err_pgd;
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crst_table_init(pgd, _REGION1_ENTRY_EMPTY);
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}
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spin_lock_bh(&mm->page_table_lock);
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/*
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* This routine gets called with mmap_lock lock held and there is
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* no reason to optimize for the case of otherwise. However, if
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* that would ever change, the below check will let us know.
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*/
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VM_BUG_ON(asce_limit != mm->context.asce_limit);
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if (p4d) {
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__pgd = (unsigned long *) mm->pgd;
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p4d_populate(mm, (p4d_t *) p4d, (pud_t *) __pgd);
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mm->pgd = (pgd_t *) p4d;
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mm->context.asce_limit = _REGION1_SIZE;
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mm->context.asce = __pa(mm->pgd) | _ASCE_TABLE_LENGTH |
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_ASCE_USER_BITS | _ASCE_TYPE_REGION2;
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mm_inc_nr_puds(mm);
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}
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if (pgd) {
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__pgd = (unsigned long *) mm->pgd;
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pgd_populate(mm, (pgd_t *) pgd, (p4d_t *) __pgd);
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mm->pgd = (pgd_t *) pgd;
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mm->context.asce_limit = TASK_SIZE_MAX;
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mm->context.asce = __pa(mm->pgd) | _ASCE_TABLE_LENGTH |
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_ASCE_USER_BITS | _ASCE_TYPE_REGION1;
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}
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spin_unlock_bh(&mm->page_table_lock);
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on_each_cpu(__crst_table_upgrade, mm, 0);
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return 0;
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err_pgd:
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crst_table_free(mm, p4d);
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err_p4d:
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return -ENOMEM;
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}
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static inline unsigned int atomic_xor_bits(atomic_t *v, unsigned int bits)
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{
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unsigned int old, new;
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do {
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old = atomic_read(v);
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new = old ^ bits;
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} while (atomic_cmpxchg(v, old, new) != old);
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return new;
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}
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#ifdef CONFIG_PGSTE
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struct page *page_table_alloc_pgste(struct mm_struct *mm)
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{
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struct page *page;
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u64 *table;
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page = alloc_page(GFP_KERNEL);
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if (page) {
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table = (u64 *)page_to_virt(page);
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memset64(table, _PAGE_INVALID, PTRS_PER_PTE);
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memset64(table + PTRS_PER_PTE, 0, PTRS_PER_PTE);
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}
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return page;
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}
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void page_table_free_pgste(struct page *page)
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{
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__free_page(page);
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}
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#endif /* CONFIG_PGSTE */
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/*
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* A 2KB-pgtable is either upper or lower half of a normal page.
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* The second half of the page may be unused or used as another
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* 2KB-pgtable.
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*
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* Whenever possible the parent page for a new 2KB-pgtable is picked
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* from the list of partially allocated pages mm_context_t::pgtable_list.
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* In case the list is empty a new parent page is allocated and added to
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* the list.
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*
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* When a parent page gets fully allocated it contains 2KB-pgtables in both
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* upper and lower halves and is removed from mm_context_t::pgtable_list.
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*
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* When 2KB-pgtable is freed from to fully allocated parent page that
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* page turns partially allocated and added to mm_context_t::pgtable_list.
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*
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* If 2KB-pgtable is freed from the partially allocated parent page that
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* page turns unused and gets removed from mm_context_t::pgtable_list.
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* Furthermore, the unused parent page is released.
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*
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* As follows from the above, no unallocated or fully allocated parent
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* pages are contained in mm_context_t::pgtable_list.
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*
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* The upper byte (bits 24-31) of the parent page _refcount is used
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* for tracking contained 2KB-pgtables and has the following format:
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*
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* PP AA
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* 01234567 upper byte (bits 24-31) of struct page::_refcount
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* || ||
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* || |+--- upper 2KB-pgtable is allocated
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* || +---- lower 2KB-pgtable is allocated
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* |+------- upper 2KB-pgtable is pending for removal
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* +-------- lower 2KB-pgtable is pending for removal
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*
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* (See commit 620b4e903179 ("s390: use _refcount for pgtables") on why
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* using _refcount is possible).
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*
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* When 2KB-pgtable is allocated the corresponding AA bit is set to 1.
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* The parent page is either:
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* - added to mm_context_t::pgtable_list in case the second half of the
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* parent page is still unallocated;
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* - removed from mm_context_t::pgtable_list in case both hales of the
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* parent page are allocated;
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* These operations are protected with mm_context_t::lock.
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*
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* When 2KB-pgtable is deallocated the corresponding AA bit is set to 0
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* and the corresponding PP bit is set to 1 in a single atomic operation.
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* Thus, PP and AA bits corresponding to the same 2KB-pgtable are mutually
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* exclusive and may never be both set to 1!
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* The parent page is either:
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* - added to mm_context_t::pgtable_list in case the second half of the
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* parent page is still allocated;
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* - removed from mm_context_t::pgtable_list in case the second half of
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* the parent page is unallocated;
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* These operations are protected with mm_context_t::lock.
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*
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* It is important to understand that mm_context_t::lock only protects
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* mm_context_t::pgtable_list and AA bits, but not the parent page itself
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* and PP bits.
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*
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* Releasing the parent page happens whenever the PP bit turns from 1 to 0,
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* while both AA bits and the second PP bit are already unset. Then the
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* parent page does not contain any 2KB-pgtable fragment anymore, and it has
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* also been removed from mm_context_t::pgtable_list. It is safe to release
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* the page therefore.
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*
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* PGSTE memory spaces use full 4KB-pgtables and do not need most of the
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* logic described above. Both AA bits are set to 1 to denote a 4KB-pgtable
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* while the PP bits are never used, nor such a page is added to or removed
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* from mm_context_t::pgtable_list.
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*/
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unsigned long *page_table_alloc(struct mm_struct *mm)
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{
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unsigned long *table;
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struct page *page;
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unsigned int mask, bit;
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/* Try to get a fragment of a 4K page as a 2K page table */
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if (!mm_alloc_pgste(mm)) {
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table = NULL;
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spin_lock_bh(&mm->context.lock);
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if (!list_empty(&mm->context.pgtable_list)) {
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page = list_first_entry(&mm->context.pgtable_list,
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struct page, lru);
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mask = atomic_read(&page->_refcount) >> 24;
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/*
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* The pending removal bits must also be checked.
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* Failure to do so might lead to an impossible
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* value of (i.e 0x13 or 0x23) written to _refcount.
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* Such values violate the assumption that pending and
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* allocation bits are mutually exclusive, and the rest
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* of the code unrails as result. That could lead to
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* a whole bunch of races and corruptions.
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*/
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mask = (mask | (mask >> 4)) & 0x03U;
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if (mask != 0x03U) {
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table = (unsigned long *) page_to_virt(page);
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bit = mask & 1; /* =1 -> second 2K */
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if (bit)
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table += PTRS_PER_PTE;
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atomic_xor_bits(&page->_refcount,
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0x01U << (bit + 24));
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list_del(&page->lru);
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}
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}
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spin_unlock_bh(&mm->context.lock);
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if (table)
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return table;
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}
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/* Allocate a fresh page */
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page = alloc_page(GFP_KERNEL);
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if (!page)
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return NULL;
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if (!pgtable_pte_page_ctor(page)) {
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__free_page(page);
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return NULL;
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}
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arch_set_page_dat(page, 0);
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/* Initialize page table */
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table = (unsigned long *) page_to_virt(page);
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if (mm_alloc_pgste(mm)) {
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/* Return 4K page table with PGSTEs */
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atomic_xor_bits(&page->_refcount, 0x03U << 24);
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memset64((u64 *)table, _PAGE_INVALID, PTRS_PER_PTE);
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memset64((u64 *)table + PTRS_PER_PTE, 0, PTRS_PER_PTE);
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} else {
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/* Return the first 2K fragment of the page */
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atomic_xor_bits(&page->_refcount, 0x01U << 24);
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memset64((u64 *)table, _PAGE_INVALID, 2 * PTRS_PER_PTE);
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spin_lock_bh(&mm->context.lock);
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list_add(&page->lru, &mm->context.pgtable_list);
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spin_unlock_bh(&mm->context.lock);
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}
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return table;
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}
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static void page_table_release_check(struct page *page, void *table,
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unsigned int half, unsigned int mask)
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{
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char msg[128];
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if (!IS_ENABLED(CONFIG_DEBUG_VM) || !mask)
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return;
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snprintf(msg, sizeof(msg),
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"Invalid pgtable %p release half 0x%02x mask 0x%02x",
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table, half, mask);
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dump_page(page, msg);
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}
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void page_table_free(struct mm_struct *mm, unsigned long *table)
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{
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unsigned int mask, bit, half;
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struct page *page;
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page = virt_to_page(table);
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if (!mm_alloc_pgste(mm)) {
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/* Free 2K page table fragment of a 4K page */
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bit = ((unsigned long) table & ~PAGE_MASK)/(PTRS_PER_PTE*sizeof(pte_t));
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spin_lock_bh(&mm->context.lock);
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/*
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* Mark the page for delayed release. The actual release
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* will happen outside of the critical section from this
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* function or from __tlb_remove_table()
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*/
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mask = atomic_xor_bits(&page->_refcount, 0x11U << (bit + 24));
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mask >>= 24;
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if (mask & 0x03U)
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list_add(&page->lru, &mm->context.pgtable_list);
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else
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list_del(&page->lru);
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spin_unlock_bh(&mm->context.lock);
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mask = atomic_xor_bits(&page->_refcount, 0x10U << (bit + 24));
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mask >>= 24;
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if (mask != 0x00U)
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return;
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half = 0x01U << bit;
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} else {
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half = 0x03U;
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mask = atomic_xor_bits(&page->_refcount, 0x03U << 24);
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mask >>= 24;
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}
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page_table_release_check(page, table, half, mask);
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pgtable_pte_page_dtor(page);
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__free_page(page);
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}
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void page_table_free_rcu(struct mmu_gather *tlb, unsigned long *table,
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unsigned long vmaddr)
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{
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struct mm_struct *mm;
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struct page *page;
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unsigned int bit, mask;
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mm = tlb->mm;
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page = virt_to_page(table);
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if (mm_alloc_pgste(mm)) {
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gmap_unlink(mm, table, vmaddr);
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table = (unsigned long *) ((unsigned long)table | 0x03U);
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tlb_remove_table(tlb, table);
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return;
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}
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bit = ((unsigned long) table & ~PAGE_MASK) / (PTRS_PER_PTE*sizeof(pte_t));
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spin_lock_bh(&mm->context.lock);
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/*
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* Mark the page for delayed release. The actual release will happen
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* outside of the critical section from __tlb_remove_table() or from
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* page_table_free()
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*/
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mask = atomic_xor_bits(&page->_refcount, 0x11U << (bit + 24));
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mask >>= 24;
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if (mask & 0x03U)
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list_add_tail(&page->lru, &mm->context.pgtable_list);
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else
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list_del(&page->lru);
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spin_unlock_bh(&mm->context.lock);
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table = (unsigned long *) ((unsigned long) table | (0x01U << bit));
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tlb_remove_table(tlb, table);
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}
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void __tlb_remove_table(void *_table)
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{
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unsigned int mask = (unsigned long) _table & 0x03U, half = mask;
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void *table = (void *)((unsigned long) _table ^ mask);
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struct page *page = virt_to_page(table);
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switch (half) {
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case 0x00U: /* pmd, pud, or p4d */
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free_pages((unsigned long)table, CRST_ALLOC_ORDER);
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return;
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case 0x01U: /* lower 2K of a 4K page table */
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case 0x02U: /* higher 2K of a 4K page table */
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mask = atomic_xor_bits(&page->_refcount, mask << (4 + 24));
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mask >>= 24;
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if (mask != 0x00U)
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return;
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break;
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case 0x03U: /* 4K page table with pgstes */
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mask = atomic_xor_bits(&page->_refcount, 0x03U << 24);
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mask >>= 24;
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break;
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}
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page_table_release_check(page, table, half, mask);
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pgtable_pte_page_dtor(page);
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__free_page(page);
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}
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/*
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* Base infrastructure required to generate basic asces, region, segment,
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* and page tables that do not make use of enhanced features like EDAT1.
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*/
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static struct kmem_cache *base_pgt_cache;
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static unsigned long *base_pgt_alloc(void)
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{
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unsigned long *table;
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table = kmem_cache_alloc(base_pgt_cache, GFP_KERNEL);
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if (table)
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memset64((u64 *)table, _PAGE_INVALID, PTRS_PER_PTE);
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return table;
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}
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static void base_pgt_free(unsigned long *table)
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{
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kmem_cache_free(base_pgt_cache, table);
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}
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static unsigned long *base_crst_alloc(unsigned long val)
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{
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unsigned long *table;
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table = (unsigned long *)__get_free_pages(GFP_KERNEL, CRST_ALLOC_ORDER);
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if (table)
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crst_table_init(table, val);
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return table;
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}
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static void base_crst_free(unsigned long *table)
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{
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free_pages((unsigned long)table, CRST_ALLOC_ORDER);
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}
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#define BASE_ADDR_END_FUNC(NAME, SIZE) \
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static inline unsigned long base_##NAME##_addr_end(unsigned long addr, \
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unsigned long end) \
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{ \
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unsigned long next = (addr + (SIZE)) & ~((SIZE) - 1); \
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\
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return (next - 1) < (end - 1) ? next : end; \
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}
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BASE_ADDR_END_FUNC(page, _PAGE_SIZE)
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BASE_ADDR_END_FUNC(segment, _SEGMENT_SIZE)
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BASE_ADDR_END_FUNC(region3, _REGION3_SIZE)
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BASE_ADDR_END_FUNC(region2, _REGION2_SIZE)
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BASE_ADDR_END_FUNC(region1, _REGION1_SIZE)
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static inline unsigned long base_lra(unsigned long address)
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{
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unsigned long real;
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asm volatile(
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" lra %0,0(%1)\n"
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: "=d" (real) : "a" (address) : "cc");
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return real;
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}
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static int base_page_walk(unsigned long *origin, unsigned long addr,
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unsigned long end, int alloc)
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{
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unsigned long *pte, next;
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if (!alloc)
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return 0;
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pte = origin;
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pte += (addr & _PAGE_INDEX) >> _PAGE_SHIFT;
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do {
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next = base_page_addr_end(addr, end);
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*pte = base_lra(addr);
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} while (pte++, addr = next, addr < end);
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return 0;
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}
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static int base_segment_walk(unsigned long *origin, unsigned long addr,
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unsigned long end, int alloc)
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{
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unsigned long *ste, next, *table;
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int rc;
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ste = origin;
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ste += (addr & _SEGMENT_INDEX) >> _SEGMENT_SHIFT;
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do {
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next = base_segment_addr_end(addr, end);
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if (*ste & _SEGMENT_ENTRY_INVALID) {
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if (!alloc)
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continue;
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table = base_pgt_alloc();
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if (!table)
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return -ENOMEM;
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*ste = __pa(table) | _SEGMENT_ENTRY;
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}
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table = __va(*ste & _SEGMENT_ENTRY_ORIGIN);
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rc = base_page_walk(table, addr, next, alloc);
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if (rc)
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return rc;
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if (!alloc)
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base_pgt_free(table);
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cond_resched();
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} while (ste++, addr = next, addr < end);
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return 0;
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}
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static int base_region3_walk(unsigned long *origin, unsigned long addr,
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unsigned long end, int alloc)
|
|
{
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unsigned long *rtte, next, *table;
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int rc;
|
|
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rtte = origin;
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rtte += (addr & _REGION3_INDEX) >> _REGION3_SHIFT;
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do {
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next = base_region3_addr_end(addr, end);
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if (*rtte & _REGION_ENTRY_INVALID) {
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if (!alloc)
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continue;
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table = base_crst_alloc(_SEGMENT_ENTRY_EMPTY);
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if (!table)
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return -ENOMEM;
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*rtte = __pa(table) | _REGION3_ENTRY;
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}
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table = __va(*rtte & _REGION_ENTRY_ORIGIN);
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rc = base_segment_walk(table, addr, next, alloc);
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if (rc)
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return rc;
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if (!alloc)
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base_crst_free(table);
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} while (rtte++, addr = next, addr < end);
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return 0;
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}
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static int base_region2_walk(unsigned long *origin, unsigned long addr,
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unsigned long end, int alloc)
|
|
{
|
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unsigned long *rste, next, *table;
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|
int rc;
|
|
|
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rste = origin;
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rste += (addr & _REGION2_INDEX) >> _REGION2_SHIFT;
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do {
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next = base_region2_addr_end(addr, end);
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if (*rste & _REGION_ENTRY_INVALID) {
|
|
if (!alloc)
|
|
continue;
|
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table = base_crst_alloc(_REGION3_ENTRY_EMPTY);
|
|
if (!table)
|
|
return -ENOMEM;
|
|
*rste = __pa(table) | _REGION2_ENTRY;
|
|
}
|
|
table = __va(*rste & _REGION_ENTRY_ORIGIN);
|
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rc = base_region3_walk(table, addr, next, alloc);
|
|
if (rc)
|
|
return rc;
|
|
if (!alloc)
|
|
base_crst_free(table);
|
|
} while (rste++, addr = next, addr < end);
|
|
return 0;
|
|
}
|
|
|
|
static int base_region1_walk(unsigned long *origin, unsigned long addr,
|
|
unsigned long end, int alloc)
|
|
{
|
|
unsigned long *rfte, next, *table;
|
|
int rc;
|
|
|
|
rfte = origin;
|
|
rfte += (addr & _REGION1_INDEX) >> _REGION1_SHIFT;
|
|
do {
|
|
next = base_region1_addr_end(addr, end);
|
|
if (*rfte & _REGION_ENTRY_INVALID) {
|
|
if (!alloc)
|
|
continue;
|
|
table = base_crst_alloc(_REGION2_ENTRY_EMPTY);
|
|
if (!table)
|
|
return -ENOMEM;
|
|
*rfte = __pa(table) | _REGION1_ENTRY;
|
|
}
|
|
table = __va(*rfte & _REGION_ENTRY_ORIGIN);
|
|
rc = base_region2_walk(table, addr, next, alloc);
|
|
if (rc)
|
|
return rc;
|
|
if (!alloc)
|
|
base_crst_free(table);
|
|
} while (rfte++, addr = next, addr < end);
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* base_asce_free - free asce and tables returned from base_asce_alloc()
|
|
* @asce: asce to be freed
|
|
*
|
|
* Frees all region, segment, and page tables that were allocated with a
|
|
* corresponding base_asce_alloc() call.
|
|
*/
|
|
void base_asce_free(unsigned long asce)
|
|
{
|
|
unsigned long *table = __va(asce & _ASCE_ORIGIN);
|
|
|
|
if (!asce)
|
|
return;
|
|
switch (asce & _ASCE_TYPE_MASK) {
|
|
case _ASCE_TYPE_SEGMENT:
|
|
base_segment_walk(table, 0, _REGION3_SIZE, 0);
|
|
break;
|
|
case _ASCE_TYPE_REGION3:
|
|
base_region3_walk(table, 0, _REGION2_SIZE, 0);
|
|
break;
|
|
case _ASCE_TYPE_REGION2:
|
|
base_region2_walk(table, 0, _REGION1_SIZE, 0);
|
|
break;
|
|
case _ASCE_TYPE_REGION1:
|
|
base_region1_walk(table, 0, TASK_SIZE_MAX, 0);
|
|
break;
|
|
}
|
|
base_crst_free(table);
|
|
}
|
|
|
|
static int base_pgt_cache_init(void)
|
|
{
|
|
static DEFINE_MUTEX(base_pgt_cache_mutex);
|
|
unsigned long sz = _PAGE_TABLE_SIZE;
|
|
|
|
if (base_pgt_cache)
|
|
return 0;
|
|
mutex_lock(&base_pgt_cache_mutex);
|
|
if (!base_pgt_cache)
|
|
base_pgt_cache = kmem_cache_create("base_pgt", sz, sz, 0, NULL);
|
|
mutex_unlock(&base_pgt_cache_mutex);
|
|
return base_pgt_cache ? 0 : -ENOMEM;
|
|
}
|
|
|
|
/**
|
|
* base_asce_alloc - create kernel mapping without enhanced DAT features
|
|
* @addr: virtual start address of kernel mapping
|
|
* @num_pages: number of consecutive pages
|
|
*
|
|
* Generate an asce, including all required region, segment and page tables,
|
|
* that can be used to access the virtual kernel mapping. The difference is
|
|
* that the returned asce does not make use of any enhanced DAT features like
|
|
* e.g. large pages. This is required for some I/O functions that pass an
|
|
* asce, like e.g. some service call requests.
|
|
*
|
|
* Note: the returned asce may NEVER be attached to any cpu. It may only be
|
|
* used for I/O requests. tlb entries that might result because the
|
|
* asce was attached to a cpu won't be cleared.
|
|
*/
|
|
unsigned long base_asce_alloc(unsigned long addr, unsigned long num_pages)
|
|
{
|
|
unsigned long asce, *table, end;
|
|
int rc;
|
|
|
|
if (base_pgt_cache_init())
|
|
return 0;
|
|
end = addr + num_pages * PAGE_SIZE;
|
|
if (end <= _REGION3_SIZE) {
|
|
table = base_crst_alloc(_SEGMENT_ENTRY_EMPTY);
|
|
if (!table)
|
|
return 0;
|
|
rc = base_segment_walk(table, addr, end, 1);
|
|
asce = __pa(table) | _ASCE_TYPE_SEGMENT | _ASCE_TABLE_LENGTH;
|
|
} else if (end <= _REGION2_SIZE) {
|
|
table = base_crst_alloc(_REGION3_ENTRY_EMPTY);
|
|
if (!table)
|
|
return 0;
|
|
rc = base_region3_walk(table, addr, end, 1);
|
|
asce = __pa(table) | _ASCE_TYPE_REGION3 | _ASCE_TABLE_LENGTH;
|
|
} else if (end <= _REGION1_SIZE) {
|
|
table = base_crst_alloc(_REGION2_ENTRY_EMPTY);
|
|
if (!table)
|
|
return 0;
|
|
rc = base_region2_walk(table, addr, end, 1);
|
|
asce = __pa(table) | _ASCE_TYPE_REGION2 | _ASCE_TABLE_LENGTH;
|
|
} else {
|
|
table = base_crst_alloc(_REGION1_ENTRY_EMPTY);
|
|
if (!table)
|
|
return 0;
|
|
rc = base_region1_walk(table, addr, end, 1);
|
|
asce = __pa(table) | _ASCE_TYPE_REGION1 | _ASCE_TABLE_LENGTH;
|
|
}
|
|
if (rc) {
|
|
base_asce_free(asce);
|
|
asce = 0;
|
|
}
|
|
return asce;
|
|
}
|