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-rw-r--r--fs/erofs/utils.c287
1 files changed, 0 insertions, 287 deletions
diff --git a/fs/erofs/utils.c b/fs/erofs/utils.c
deleted file mode 100644
index 518bdd69c823..000000000000
--- a/fs/erofs/utils.c
+++ /dev/null
@@ -1,287 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-only
-/*
- * Copyright (C) 2018 HUAWEI, Inc.
- * https://www.huawei.com/
- */
-#include "internal.h"
-
-struct page *erofs_allocpage(struct page **pagepool, gfp_t gfp)
-{
- struct page *page = *pagepool;
-
- if (page) {
- DBG_BUGON(page_ref_count(page) != 1);
- *pagepool = (struct page *)page_private(page);
- } else {
- page = alloc_page(gfp);
- }
- return page;
-}
-
-void erofs_release_pages(struct page **pagepool)
-{
- while (*pagepool) {
- struct page *page = *pagepool;
-
- *pagepool = (struct page *)page_private(page);
- put_page(page);
- }
-}
-
-#ifdef CONFIG_EROFS_FS_ZIP
-/* global shrink count (for all mounted EROFS instances) */
-static atomic_long_t erofs_global_shrink_cnt;
-
-static bool erofs_workgroup_get(struct erofs_workgroup *grp)
-{
- if (lockref_get_not_zero(&grp->lockref))
- return true;
-
- spin_lock(&grp->lockref.lock);
- if (__lockref_is_dead(&grp->lockref)) {
- spin_unlock(&grp->lockref.lock);
- return false;
- }
-
- if (!grp->lockref.count++)
- atomic_long_dec(&erofs_global_shrink_cnt);
- spin_unlock(&grp->lockref.lock);
- return true;
-}
-
-struct erofs_workgroup *erofs_find_workgroup(struct super_block *sb,
- pgoff_t index)
-{
- struct erofs_sb_info *sbi = EROFS_SB(sb);
- struct erofs_workgroup *grp;
-
-repeat:
- rcu_read_lock();
- grp = xa_load(&sbi->managed_pslots, index);
- if (grp) {
- if (!erofs_workgroup_get(grp)) {
- /* prefer to relax rcu read side */
- rcu_read_unlock();
- goto repeat;
- }
-
- DBG_BUGON(index != grp->index);
- }
- rcu_read_unlock();
- return grp;
-}
-
-struct erofs_workgroup *erofs_insert_workgroup(struct super_block *sb,
- struct erofs_workgroup *grp)
-{
- struct erofs_sb_info *const sbi = EROFS_SB(sb);
- struct erofs_workgroup *pre;
-
- DBG_BUGON(grp->lockref.count < 1);
-repeat:
- xa_lock(&sbi->managed_pslots);
- pre = __xa_cmpxchg(&sbi->managed_pslots, grp->index,
- NULL, grp, GFP_KERNEL);
- if (pre) {
- if (xa_is_err(pre)) {
- pre = ERR_PTR(xa_err(pre));
- } else if (!erofs_workgroup_get(pre)) {
- /* try to legitimize the current in-tree one */
- xa_unlock(&sbi->managed_pslots);
- cond_resched();
- goto repeat;
- }
- grp = pre;
- }
- xa_unlock(&sbi->managed_pslots);
- return grp;
-}
-
-static void __erofs_workgroup_free(struct erofs_workgroup *grp)
-{
- atomic_long_dec(&erofs_global_shrink_cnt);
- erofs_workgroup_free_rcu(grp);
-}
-
-void erofs_workgroup_put(struct erofs_workgroup *grp)
-{
- if (lockref_put_or_lock(&grp->lockref))
- return;
-
- DBG_BUGON(__lockref_is_dead(&grp->lockref));
- if (grp->lockref.count == 1)
- atomic_long_inc(&erofs_global_shrink_cnt);
- --grp->lockref.count;
- spin_unlock(&grp->lockref.lock);
-}
-
-static bool erofs_try_to_release_workgroup(struct erofs_sb_info *sbi,
- struct erofs_workgroup *grp)
-{
- int free = false;
-
- spin_lock(&grp->lockref.lock);
- if (grp->lockref.count)
- goto out;
-
- /*
- * Note that all cached pages should be detached before deleted from
- * the XArray. Otherwise some cached pages could be still attached to
- * the orphan old workgroup when the new one is available in the tree.
- */
- if (erofs_try_to_free_all_cached_folios(sbi, grp))
- goto out;
-
- /*
- * It's impossible to fail after the workgroup is freezed,
- * however in order to avoid some race conditions, add a
- * DBG_BUGON to observe this in advance.
- */
- DBG_BUGON(__xa_erase(&sbi->managed_pslots, grp->index) != grp);
-
- lockref_mark_dead(&grp->lockref);
- free = true;
-out:
- spin_unlock(&grp->lockref.lock);
- if (free)
- __erofs_workgroup_free(grp);
- return free;
-}
-
-static unsigned long erofs_shrink_workstation(struct erofs_sb_info *sbi,
- unsigned long nr_shrink)
-{
- struct erofs_workgroup *grp;
- unsigned int freed = 0;
- unsigned long index;
-
- xa_lock(&sbi->managed_pslots);
- xa_for_each(&sbi->managed_pslots, index, grp) {
- /* try to shrink each valid workgroup */
- if (!erofs_try_to_release_workgroup(sbi, grp))
- continue;
- xa_unlock(&sbi->managed_pslots);
-
- ++freed;
- if (!--nr_shrink)
- return freed;
- xa_lock(&sbi->managed_pslots);
- }
- xa_unlock(&sbi->managed_pslots);
- return freed;
-}
-
-/* protected by 'erofs_sb_list_lock' */
-static unsigned int shrinker_run_no;
-
-/* protects the mounted 'erofs_sb_list' */
-static DEFINE_SPINLOCK(erofs_sb_list_lock);
-static LIST_HEAD(erofs_sb_list);
-
-void erofs_shrinker_register(struct super_block *sb)
-{
- struct erofs_sb_info *sbi = EROFS_SB(sb);
-
- mutex_init(&sbi->umount_mutex);
-
- spin_lock(&erofs_sb_list_lock);
- list_add(&sbi->list, &erofs_sb_list);
- spin_unlock(&erofs_sb_list_lock);
-}
-
-void erofs_shrinker_unregister(struct super_block *sb)
-{
- struct erofs_sb_info *const sbi = EROFS_SB(sb);
-
- mutex_lock(&sbi->umount_mutex);
- /* clean up all remaining workgroups in memory */
- erofs_shrink_workstation(sbi, ~0UL);
-
- spin_lock(&erofs_sb_list_lock);
- list_del(&sbi->list);
- spin_unlock(&erofs_sb_list_lock);
- mutex_unlock(&sbi->umount_mutex);
-}
-
-static unsigned long erofs_shrink_count(struct shrinker *shrink,
- struct shrink_control *sc)
-{
- return atomic_long_read(&erofs_global_shrink_cnt);
-}
-
-static unsigned long erofs_shrink_scan(struct shrinker *shrink,
- struct shrink_control *sc)
-{
- struct erofs_sb_info *sbi;
- struct list_head *p;
-
- unsigned long nr = sc->nr_to_scan;
- unsigned int run_no;
- unsigned long freed = 0;
-
- spin_lock(&erofs_sb_list_lock);
- do {
- run_no = ++shrinker_run_no;
- } while (run_no == 0);
-
- /* Iterate over all mounted superblocks and try to shrink them */
- p = erofs_sb_list.next;
- while (p != &erofs_sb_list) {
- sbi = list_entry(p, struct erofs_sb_info, list);
-
- /*
- * We move the ones we do to the end of the list, so we stop
- * when we see one we have already done.
- */
- if (sbi->shrinker_run_no == run_no)
- break;
-
- if (!mutex_trylock(&sbi->umount_mutex)) {
- p = p->next;
- continue;
- }
-
- spin_unlock(&erofs_sb_list_lock);
- sbi->shrinker_run_no = run_no;
-
- freed += erofs_shrink_workstation(sbi, nr - freed);
-
- spin_lock(&erofs_sb_list_lock);
- /* Get the next list element before we move this one */
- p = p->next;
-
- /*
- * Move this one to the end of the list to provide some
- * fairness.
- */
- list_move_tail(&sbi->list, &erofs_sb_list);
- mutex_unlock(&sbi->umount_mutex);
-
- if (freed >= nr)
- break;
- }
- spin_unlock(&erofs_sb_list_lock);
- return freed;
-}
-
-static struct shrinker *erofs_shrinker_info;
-
-int __init erofs_init_shrinker(void)
-{
- erofs_shrinker_info = shrinker_alloc(0, "erofs-shrinker");
- if (!erofs_shrinker_info)
- return -ENOMEM;
-
- erofs_shrinker_info->count_objects = erofs_shrink_count;
- erofs_shrinker_info->scan_objects = erofs_shrink_scan;
-
- shrinker_register(erofs_shrinker_info);
-
- return 0;
-}
-
-void erofs_exit_shrinker(void)
-{
- shrinker_free(erofs_shrinker_info);
-}
-#endif /* !CONFIG_EROFS_FS_ZIP */