diff options
Diffstat (limited to 'fs/f2fs/gc.c')
| -rw-r--r-- | fs/f2fs/gc.c | 2116 |
1 files changed, 2116 insertions, 0 deletions
diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c new file mode 100644 index 000000000..dfa99cd19 --- /dev/null +++ b/fs/f2fs/gc.c @@ -0,0 +1,2116 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * fs/f2fs/gc.c + * + * Copyright (c) 2012 Samsung Electronics Co., Ltd. + * http://www.samsung.com/ + */ +#include <linux/fs.h> +#include <linux/module.h> +#include <linux/mount.h> +#include <linux/backing-dev.h> +#include <linux/init.h> +#include <linux/f2fs_fs.h> +#include <linux/kthread.h> +#include <linux/delay.h> +#include <linux/freezer.h> +#include <linux/sched/signal.h> + +#include "f2fs.h" +#include "node.h" +#include "segment.h" +#include "gc.h" +#include <trace/events/f2fs.h> + +static struct kmem_cache *victim_entry_slab; + +static unsigned int count_bits(const unsigned long *addr, + unsigned int offset, unsigned int len); + +static int gc_thread_func(void *data) +{ + struct f2fs_sb_info *sbi = data; + struct f2fs_gc_kthread *gc_th = sbi->gc_thread; + wait_queue_head_t *wq = &sbi->gc_thread->gc_wait_queue_head; + unsigned int wait_ms; + + wait_ms = gc_th->min_sleep_time; + + set_freezable(); + do { + bool sync_mode; + + wait_event_interruptible_timeout(*wq, + kthread_should_stop() || freezing(current) || + gc_th->gc_wake, + msecs_to_jiffies(wait_ms)); + + /* give it a try one time */ + if (gc_th->gc_wake) + gc_th->gc_wake = 0; + + if (try_to_freeze()) { + stat_other_skip_bggc_count(sbi); + continue; + } + if (kthread_should_stop()) + break; + + if (sbi->sb->s_writers.frozen >= SB_FREEZE_WRITE) { + increase_sleep_time(gc_th, &wait_ms); + stat_other_skip_bggc_count(sbi); + continue; + } + + if (time_to_inject(sbi, FAULT_CHECKPOINT)) { + f2fs_show_injection_info(sbi, FAULT_CHECKPOINT); + f2fs_stop_checkpoint(sbi, false); + } + + if (!sb_start_write_trylock(sbi->sb)) { + stat_other_skip_bggc_count(sbi); + continue; + } + + /* + * [GC triggering condition] + * 0. GC is not conducted currently. + * 1. There are enough dirty segments. + * 2. IO subsystem is idle by checking the # of writeback pages. + * 3. IO subsystem is idle by checking the # of requests in + * bdev's request list. + * + * Note) We have to avoid triggering GCs frequently. + * Because it is possible that some segments can be + * invalidated soon after by user update or deletion. + * So, I'd like to wait some time to collect dirty segments. + */ + if (sbi->gc_mode == GC_URGENT_HIGH) { + wait_ms = gc_th->urgent_sleep_time; + down_write(&sbi->gc_lock); + goto do_gc; + } + + if (!down_write_trylock(&sbi->gc_lock)) { + stat_other_skip_bggc_count(sbi); + goto next; + } + + if (!is_idle(sbi, GC_TIME)) { + increase_sleep_time(gc_th, &wait_ms); + up_write(&sbi->gc_lock); + stat_io_skip_bggc_count(sbi); + goto next; + } + + if (has_enough_invalid_blocks(sbi)) + decrease_sleep_time(gc_th, &wait_ms); + else + increase_sleep_time(gc_th, &wait_ms); +do_gc: + stat_inc_bggc_count(sbi->stat_info); + + sync_mode = F2FS_OPTION(sbi).bggc_mode == BGGC_MODE_SYNC; + + /* if return value is not zero, no victim was selected */ + if (f2fs_gc(sbi, sync_mode, true, false, NULL_SEGNO)) + wait_ms = gc_th->no_gc_sleep_time; + + trace_f2fs_background_gc(sbi->sb, wait_ms, + prefree_segments(sbi), free_segments(sbi)); + + /* balancing f2fs's metadata periodically */ + f2fs_balance_fs_bg(sbi, true); +next: + sb_end_write(sbi->sb); + + } while (!kthread_should_stop()); + return 0; +} + +int f2fs_start_gc_thread(struct f2fs_sb_info *sbi) +{ + struct f2fs_gc_kthread *gc_th; + dev_t dev = sbi->sb->s_bdev->bd_dev; + int err = 0; + + gc_th = f2fs_kmalloc(sbi, sizeof(struct f2fs_gc_kthread), GFP_KERNEL); + if (!gc_th) { + err = -ENOMEM; + goto out; + } + + gc_th->urgent_sleep_time = DEF_GC_THREAD_URGENT_SLEEP_TIME; + gc_th->min_sleep_time = DEF_GC_THREAD_MIN_SLEEP_TIME; + gc_th->max_sleep_time = DEF_GC_THREAD_MAX_SLEEP_TIME; + gc_th->no_gc_sleep_time = DEF_GC_THREAD_NOGC_SLEEP_TIME; + + gc_th->gc_wake= 0; + + sbi->gc_thread = gc_th; + init_waitqueue_head(&sbi->gc_thread->gc_wait_queue_head); + sbi->gc_thread->f2fs_gc_task = kthread_run(gc_thread_func, sbi, + "f2fs_gc-%u:%u", MAJOR(dev), MINOR(dev)); + if (IS_ERR(gc_th->f2fs_gc_task)) { + err = PTR_ERR(gc_th->f2fs_gc_task); + kfree(gc_th); + sbi->gc_thread = NULL; + } +out: + return err; +} + +void f2fs_stop_gc_thread(struct f2fs_sb_info *sbi) +{ + struct f2fs_gc_kthread *gc_th = sbi->gc_thread; + if (!gc_th) + return; + kthread_stop(gc_th->f2fs_gc_task); + kfree(gc_th); + sbi->gc_thread = NULL; +} + +static int select_gc_type(struct f2fs_sb_info *sbi, int gc_type) +{ + int gc_mode; + + if (gc_type == BG_GC) { + if (sbi->am.atgc_enabled) + gc_mode = GC_AT; + else + gc_mode = GC_CB; + } else { + gc_mode = GC_GREEDY; + } + + switch (sbi->gc_mode) { + case GC_IDLE_CB: + gc_mode = GC_CB; + break; + case GC_IDLE_GREEDY: + case GC_URGENT_HIGH: + gc_mode = GC_GREEDY; + break; + case GC_IDLE_AT: + gc_mode = GC_AT; + break; + } + + return gc_mode; +} + +static void select_policy(struct f2fs_sb_info *sbi, int gc_type, + int type, struct victim_sel_policy *p) +{ + struct dirty_seglist_info *dirty_i = DIRTY_I(sbi); + + if (p->alloc_mode == SSR) { + p->gc_mode = GC_GREEDY; + p->dirty_bitmap = dirty_i->dirty_segmap[type]; + p->max_search = dirty_i->nr_dirty[type]; + p->ofs_unit = 1; + } else if (p->alloc_mode == AT_SSR) { + p->gc_mode = GC_GREEDY; + p->dirty_bitmap = dirty_i->dirty_segmap[type]; + p->max_search = dirty_i->nr_dirty[type]; + p->ofs_unit = 1; + } else { + p->gc_mode = select_gc_type(sbi, gc_type); + p->ofs_unit = sbi->segs_per_sec; + if (__is_large_section(sbi)) { + p->dirty_bitmap = dirty_i->dirty_secmap; + p->max_search = count_bits(p->dirty_bitmap, + 0, MAIN_SECS(sbi)); + } else { + p->dirty_bitmap = dirty_i->dirty_segmap[DIRTY]; + p->max_search = dirty_i->nr_dirty[DIRTY]; + } + } + + /* + * adjust candidates range, should select all dirty segments for + * foreground GC and urgent GC cases. + */ + if (gc_type != FG_GC && + (sbi->gc_mode != GC_URGENT_HIGH) && + (p->gc_mode != GC_AT && p->alloc_mode != AT_SSR) && + p->max_search > sbi->max_victim_search) + p->max_search = sbi->max_victim_search; + + /* let's select beginning hot/small space first in no_heap mode*/ + if (test_opt(sbi, NOHEAP) && + (type == CURSEG_HOT_DATA || IS_NODESEG(type))) + p->offset = 0; + else + p->offset = SIT_I(sbi)->last_victim[p->gc_mode]; +} + +static unsigned int get_max_cost(struct f2fs_sb_info *sbi, + struct victim_sel_policy *p) +{ + /* SSR allocates in a segment unit */ + if (p->alloc_mode == SSR) + return sbi->blocks_per_seg; + else if (p->alloc_mode == AT_SSR) + return UINT_MAX; + + /* LFS */ + if (p->gc_mode == GC_GREEDY) + return 2 * sbi->blocks_per_seg * p->ofs_unit; + else if (p->gc_mode == GC_CB) + return UINT_MAX; + else if (p->gc_mode == GC_AT) + return UINT_MAX; + else /* No other gc_mode */ + return 0; +} + +static unsigned int check_bg_victims(struct f2fs_sb_info *sbi) +{ + struct dirty_seglist_info *dirty_i = DIRTY_I(sbi); + unsigned int secno; + + /* + * If the gc_type is FG_GC, we can select victim segments + * selected by background GC before. + * Those segments guarantee they have small valid blocks. + */ + for_each_set_bit(secno, dirty_i->victim_secmap, MAIN_SECS(sbi)) { + if (sec_usage_check(sbi, secno)) + continue; + clear_bit(secno, dirty_i->victim_secmap); + return GET_SEG_FROM_SEC(sbi, secno); + } + return NULL_SEGNO; +} + +static unsigned int get_cb_cost(struct f2fs_sb_info *sbi, unsigned int segno) +{ + struct sit_info *sit_i = SIT_I(sbi); + unsigned int secno = GET_SEC_FROM_SEG(sbi, segno); + unsigned int start = GET_SEG_FROM_SEC(sbi, secno); + unsigned long long mtime = 0; + unsigned int vblocks; + unsigned char age = 0; + unsigned char u; + unsigned int i; + unsigned int usable_segs_per_sec = f2fs_usable_segs_in_sec(sbi, segno); + + for (i = 0; i < usable_segs_per_sec; i++) + mtime += get_seg_entry(sbi, start + i)->mtime; + vblocks = get_valid_blocks(sbi, segno, true); + + mtime = div_u64(mtime, usable_segs_per_sec); + vblocks = div_u64(vblocks, usable_segs_per_sec); + + u = (vblocks * 100) >> sbi->log_blocks_per_seg; + + /* Handle if the system time has changed by the user */ + if (mtime < sit_i->min_mtime) + sit_i->min_mtime = mtime; + if (mtime > sit_i->max_mtime) + sit_i->max_mtime = mtime; + if (sit_i->max_mtime != sit_i->min_mtime) + age = 100 - div64_u64(100 * (mtime - sit_i->min_mtime), + sit_i->max_mtime - sit_i->min_mtime); + + return UINT_MAX - ((100 * (100 - u) * age) / (100 + u)); +} + +static inline unsigned int get_gc_cost(struct f2fs_sb_info *sbi, + unsigned int segno, struct victim_sel_policy *p) +{ + if (p->alloc_mode == SSR) + return get_seg_entry(sbi, segno)->ckpt_valid_blocks; + + /* alloc_mode == LFS */ + if (p->gc_mode == GC_GREEDY) + return get_valid_blocks(sbi, segno, true); + else if (p->gc_mode == GC_CB) + return get_cb_cost(sbi, segno); + + f2fs_bug_on(sbi, 1); + return 0; +} + +static unsigned int count_bits(const unsigned long *addr, + unsigned int offset, unsigned int len) +{ + unsigned int end = offset + len, sum = 0; + + while (offset < end) { + if (test_bit(offset++, addr)) + ++sum; + } + return sum; +} + +static struct victim_entry *attach_victim_entry(struct f2fs_sb_info *sbi, + unsigned long long mtime, unsigned int segno, + struct rb_node *parent, struct rb_node **p, + bool left_most) +{ + struct atgc_management *am = &sbi->am; + struct victim_entry *ve; + + ve = f2fs_kmem_cache_alloc(victim_entry_slab, GFP_NOFS); + + ve->mtime = mtime; + ve->segno = segno; + + rb_link_node(&ve->rb_node, parent, p); + rb_insert_color_cached(&ve->rb_node, &am->root, left_most); + + list_add_tail(&ve->list, &am->victim_list); + + am->victim_count++; + + return ve; +} + +static void insert_victim_entry(struct f2fs_sb_info *sbi, + unsigned long long mtime, unsigned int segno) +{ + struct atgc_management *am = &sbi->am; + struct rb_node **p; + struct rb_node *parent = NULL; + bool left_most = true; + + p = f2fs_lookup_rb_tree_ext(sbi, &am->root, &parent, mtime, &left_most); + attach_victim_entry(sbi, mtime, segno, parent, p, left_most); +} + +static void add_victim_entry(struct f2fs_sb_info *sbi, + struct victim_sel_policy *p, unsigned int segno) +{ + struct sit_info *sit_i = SIT_I(sbi); + unsigned int secno = GET_SEC_FROM_SEG(sbi, segno); + unsigned int start = GET_SEG_FROM_SEC(sbi, secno); + unsigned long long mtime = 0; + unsigned int i; + + if (unlikely(is_sbi_flag_set(sbi, SBI_CP_DISABLED))) { + if (p->gc_mode == GC_AT && + get_valid_blocks(sbi, segno, true) == 0) + return; + } + + for (i = 0; i < sbi->segs_per_sec; i++) + mtime += get_seg_entry(sbi, start + i)->mtime; + mtime = div_u64(mtime, sbi->segs_per_sec); + + /* Handle if the system time has changed by the user */ + if (mtime < sit_i->min_mtime) + sit_i->min_mtime = mtime; + if (mtime > sit_i->max_mtime) + sit_i->max_mtime = mtime; + if (mtime < sit_i->dirty_min_mtime) + sit_i->dirty_min_mtime = mtime; + if (mtime > sit_i->dirty_max_mtime) + sit_i->dirty_max_mtime = mtime; + + /* don't choose young section as candidate */ + if (sit_i->dirty_max_mtime - mtime < p->age_threshold) + return; + + insert_victim_entry(sbi, mtime, segno); +} + +static struct rb_node *lookup_central_victim(struct f2fs_sb_info *sbi, + struct victim_sel_policy *p) +{ + struct atgc_management *am = &sbi->am; + struct rb_node *parent = NULL; + bool left_most; + + f2fs_lookup_rb_tree_ext(sbi, &am->root, &parent, p->age, &left_most); + + return parent; +} + +static void atgc_lookup_victim(struct f2fs_sb_info *sbi, + struct victim_sel_policy *p) +{ + struct sit_info *sit_i = SIT_I(sbi); + struct atgc_management *am = &sbi->am; + struct rb_root_cached *root = &am->root; + struct rb_node *node; + struct rb_entry *re; + struct victim_entry *ve; + unsigned long long total_time; + unsigned long long age, u, accu; + unsigned long long max_mtime = sit_i->dirty_max_mtime; + unsigned long long min_mtime = sit_i->dirty_min_mtime; + unsigned int sec_blocks = BLKS_PER_SEC(sbi); + unsigned int vblocks; + unsigned int dirty_threshold = max(am->max_candidate_count, + am->candidate_ratio * + am->victim_count / 100); + unsigned int age_weight = am->age_weight; + unsigned int cost; + unsigned int iter = 0; + + if (max_mtime < min_mtime) + return; + + max_mtime += 1; + total_time = max_mtime - min_mtime; + + accu = div64_u64(ULLONG_MAX, total_time); + accu = min_t(unsigned long long, div_u64(accu, 100), + DEFAULT_ACCURACY_CLASS); + + node = rb_first_cached(root); +next: + re = rb_entry_safe(node, struct rb_entry, rb_node); + if (!re) + return; + + ve = (struct victim_entry *)re; + + if (ve->mtime >= max_mtime || ve->mtime < min_mtime) + goto skip; + + /* age = 10000 * x% * 60 */ + age = div64_u64(accu * (max_mtime - ve->mtime), total_time) * + age_weight; + + vblocks = get_valid_blocks(sbi, ve->segno, true); + f2fs_bug_on(sbi, !vblocks || vblocks == sec_blocks); + + /* u = 10000 * x% * 40 */ + u = div64_u64(accu * (sec_blocks - vblocks), sec_blocks) * + (100 - age_weight); + + f2fs_bug_on(sbi, age + u >= UINT_MAX); + + cost = UINT_MAX - (age + u); + iter++; + + if (cost < p->min_cost || + (cost == p->min_cost && age > p->oldest_age)) { + p->min_cost = cost; + p->oldest_age = age; + p->min_segno = ve->segno; + } +skip: + if (iter < dirty_threshold) { + node = rb_next(node); + goto next; + } +} + +/* + * select candidates around source section in range of + * [target - dirty_threshold, target + dirty_threshold] + */ +static void atssr_lookup_victim(struct f2fs_sb_info *sbi, + struct victim_sel_policy *p) +{ + struct sit_info *sit_i = SIT_I(sbi); + struct atgc_management *am = &sbi->am; + struct rb_node *node; + struct rb_entry *re; + struct victim_entry *ve; + unsigned long long age; + unsigned long long max_mtime = sit_i->dirty_max_mtime; + unsigned long long min_mtime = sit_i->dirty_min_mtime; + unsigned int seg_blocks = sbi->blocks_per_seg; + unsigned int vblocks; + unsigned int dirty_threshold = max(am->max_candidate_count, + am->candidate_ratio * + am->victim_count / 100); + unsigned int cost; + unsigned int iter = 0; + int stage = 0; + + if (max_mtime < min_mtime) + return; + max_mtime += 1; +next_stage: + node = lookup_central_victim(sbi, p); +next_node: + re = rb_entry_safe(node, struct rb_entry, rb_node); + if (!re) { + if (stage == 0) + goto skip_stage; + return; + } + + ve = (struct victim_entry *)re; + + if (ve->mtime >= max_mtime || ve->mtime < min_mtime) + goto skip_node; + + age = max_mtime - ve->mtime; + + vblocks = get_seg_entry(sbi, ve->segno)->ckpt_valid_blocks; + f2fs_bug_on(sbi, !vblocks); + + /* rare case */ + if (vblocks == seg_blocks) + goto skip_node; + + iter++; + + age = max_mtime - abs(p->age - age); + cost = UINT_MAX - vblocks; + + if (cost < p->min_cost || + (cost == p->min_cost && age > p->oldest_age)) { + p->min_cost = cost; + p->oldest_age = age; + p->min_segno = ve->segno; + } +skip_node: + if (iter < dirty_threshold) { + if (stage == 0) + node = rb_prev(node); + else if (stage == 1) + node = rb_next(node); + goto next_node; + } +skip_stage: + if (stage < 1) { + stage++; + iter = 0; + goto next_stage; + } +} +static void lookup_victim_by_age(struct f2fs_sb_info *sbi, + struct victim_sel_policy *p) +{ + f2fs_bug_on(sbi, !f2fs_check_rb_tree_consistence(sbi, + &sbi->am.root, true)); + + if (p->gc_mode == GC_AT) + atgc_lookup_victim(sbi, p); + else if (p->alloc_mode == AT_SSR) + atssr_lookup_victim(sbi, p); + else + f2fs_bug_on(sbi, 1); +} + +static void release_victim_entry(struct f2fs_sb_info *sbi) +{ + struct atgc_management *am = &sbi->am; + struct victim_entry *ve, *tmp; + + list_for_each_entry_safe(ve, tmp, &am->victim_list, list) { + list_del(&ve->list); + kmem_cache_free(victim_entry_slab, ve); + am->victim_count--; + } + + am->root = RB_ROOT_CACHED; + + f2fs_bug_on(sbi, am->victim_count); + f2fs_bug_on(sbi, !list_empty(&am->victim_list)); +} + +/* + * This function is called from two paths. + * One is garbage collection and the other is SSR segment selection. + * When it is called during GC, it just gets a victim segment + * and it does not remove it from dirty seglist. + * When it is called from SSR segment selection, it finds a segment + * which has minimum valid blocks and removes it from dirty seglist. + */ +static int get_victim_by_default(struct f2fs_sb_info *sbi, + unsigned int *result, int gc_type, int type, + char alloc_mode, unsigned long long age) +{ + struct dirty_seglist_info *dirty_i = DIRTY_I(sbi); + struct sit_info *sm = SIT_I(sbi); + struct victim_sel_policy p; + unsigned int secno, last_victim; + unsigned int last_segment; + unsigned int nsearched; + bool is_atgc; + int ret = 0; + + mutex_lock(&dirty_i->seglist_lock); + last_segment = MAIN_SECS(sbi) * sbi->segs_per_sec; + + p.alloc_mode = alloc_mode; + p.age = age; + p.age_threshold = sbi->am.age_threshold; + +retry: + select_policy(sbi, gc_type, type, &p); + p.min_segno = NULL_SEGNO; + p.oldest_age = 0; + p.min_cost = get_max_cost(sbi, &p); + + is_atgc = (p.gc_mode == GC_AT || p.alloc_mode == AT_SSR); + nsearched = 0; + + if (is_atgc) + SIT_I(sbi)->dirty_min_mtime = ULLONG_MAX; + + if (*result != NULL_SEGNO) { + if (!get_valid_blocks(sbi, *result, false)) { + ret = -ENODATA; + goto out; + } + + if (sec_usage_check(sbi, GET_SEC_FROM_SEG(sbi, *result))) + ret = -EBUSY; + else + p.min_segno = *result; + goto out; + } + + ret = -ENODATA; + if (p.max_search == 0) + goto out; + + if (__is_large_section(sbi) && p.alloc_mode == LFS) { + if (sbi->next_victim_seg[BG_GC] != NULL_SEGNO) { + p.min_segno = sbi->next_victim_seg[BG_GC]; + *result = p.min_segno; + sbi->next_victim_seg[BG_GC] = NULL_SEGNO; + goto got_result; + } + if (gc_type == FG_GC && + sbi->next_victim_seg[FG_GC] != NULL_SEGNO) { + p.min_segno = sbi->next_victim_seg[FG_GC]; + *result = p.min_segno; + sbi->next_victim_seg[FG_GC] = NULL_SEGNO; + goto got_result; + } + } + + last_victim = sm->last_victim[p.gc_mode]; + if (p.alloc_mode == LFS && gc_type == FG_GC) { + p.min_segno = check_bg_victims(sbi); + if (p.min_segno != NULL_SEGNO) + goto got_it; + } + + while (1) { + unsigned long cost, *dirty_bitmap; + unsigned int unit_no, segno; + + dirty_bitmap = p.dirty_bitmap; + unit_no = find_next_bit(dirty_bitmap, + last_segment / p.ofs_unit, + p.offset / p.ofs_unit); + segno = unit_no * p.ofs_unit; + if (segno >= last_segment) { + if (sm->last_victim[p.gc_mode]) { + last_segment = + sm->last_victim[p.gc_mode]; + sm->last_victim[p.gc_mode] = 0; + p.offset = 0; + continue; + } + break; + } + + p.offset = segno + p.ofs_unit; + nsearched++; + +#ifdef CONFIG_F2FS_CHECK_FS + /* + * skip selecting the invalid segno (that is failed due to block + * validity check failure during GC) to avoid endless GC loop in + * such cases. + */ + if (test_bit(segno, sm->invalid_segmap)) + goto next; +#endif + + secno = GET_SEC_FROM_SEG(sbi, segno); + + if (sec_usage_check(sbi, secno)) + goto next; + + /* Don't touch checkpointed data */ + if (unlikely(is_sbi_flag_set(sbi, SBI_CP_DISABLED))) { + if (p.alloc_mode == LFS) { + /* + * LFS is set to find source section during GC. + * The victim should have no checkpointed data. + */ + if (get_ckpt_valid_blocks(sbi, segno, true)) + goto next; + } else { + /* + * SSR | AT_SSR are set to find target segment + * for writes which can be full by checkpointed + * and newly written blocks. + */ + if (!f2fs_segment_has_free_slot(sbi, segno)) + goto next; + } + } + + if (gc_type == BG_GC && test_bit(secno, dirty_i->victim_secmap)) + goto next; + + if (is_atgc) { + add_victim_entry(sbi, &p, segno); + goto next; + } + + cost = get_gc_cost(sbi, segno, &p); + + if (p.min_cost > cost) { + p.min_segno = segno; + p.min_cost = cost; + } +next: + if (nsearched >= p.max_search) { + if (!sm->last_victim[p.gc_mode] && segno <= last_victim) + sm->last_victim[p.gc_mode] = + last_victim + p.ofs_unit; + else + sm->last_victim[p.gc_mode] = segno + p.ofs_unit; + sm->last_victim[p.gc_mode] %= + (MAIN_SECS(sbi) * sbi->segs_per_sec); + break; + } + } + + /* get victim for GC_AT/AT_SSR */ + if (is_atgc) { + lookup_victim_by_age(sbi, &p); + release_victim_entry(sbi); + } + + if (is_atgc && p.min_segno == NULL_SEGNO && + sm->elapsed_time < p.age_threshold) { + p.age_threshold = 0; + goto retry; + } + + if (p.min_segno != NULL_SEGNO) { +got_it: + *result = (p.min_segno / p.ofs_unit) * p.ofs_unit; +got_result: + if (p.alloc_mode == LFS) { + secno = GET_SEC_FROM_SEG(sbi, p.min_segno); + if (gc_type == FG_GC) + sbi->cur_victim_sec = secno; + else + set_bit(secno, dirty_i->victim_secmap); + } + ret = 0; + + } +out: + if (p.min_segno != NULL_SEGNO) + trace_f2fs_get_victim(sbi->sb, type, gc_type, &p, + sbi->cur_victim_sec, + prefree_segments(sbi), free_segments(sbi)); + mutex_unlock(&dirty_i->seglist_lock); + + return ret; +} + +static const struct victim_selection default_v_ops = { + .get_victim = get_victim_by_default, +}; + +static struct inode *find_gc_inode(struct gc_inode_list *gc_list, nid_t ino) +{ + struct inode_entry *ie; + + ie = radix_tree_lookup(&gc_list->iroot, ino); + if (ie) + return ie->inode; + return NULL; +} + +static void add_gc_inode(struct gc_inode_list *gc_list, struct inode *inode) +{ + struct inode_entry *new_ie; + + if (inode == find_gc_inode(gc_list, inode->i_ino)) { + iput(inode); + return; + } + new_ie = f2fs_kmem_cache_alloc(f2fs_inode_entry_slab, GFP_NOFS); + new_ie->inode = inode; + + f2fs_radix_tree_insert(&gc_list->iroot, inode->i_ino, new_ie); + list_add_tail(&new_ie->list, &gc_list->ilist); +} + +static void put_gc_inode(struct gc_inode_list *gc_list) +{ + struct inode_entry *ie, *next_ie; + list_for_each_entry_safe(ie, next_ie, &gc_list->ilist, list) { + radix_tree_delete(&gc_list->iroot, ie->inode->i_ino); + iput(ie->inode); + list_del(&ie->list); + kmem_cache_free(f2fs_inode_entry_slab, ie); + } +} + +static int check_valid_map(struct f2fs_sb_info *sbi, + unsigned int segno, int offset) +{ + struct sit_info *sit_i = SIT_I(sbi); + struct seg_entry *sentry; + int ret; + + down_read(&sit_i->sentry_lock); + sentry = get_seg_entry(sbi, segno); + ret = f2fs_test_bit(offset, sentry->cur_valid_map); + up_read(&sit_i->sentry_lock); + return ret; +} + +/* + * This function compares node address got in summary with that in NAT. + * On validity, copy that node with cold status, otherwise (invalid node) + * ignore that. + */ +static int gc_node_segment(struct f2fs_sb_info *sbi, + struct f2fs_summary *sum, unsigned int segno, int gc_type) +{ + struct f2fs_summary *entry; + block_t start_addr; + int off; + int phase = 0; + bool fggc = (gc_type == FG_GC); + int submitted = 0; + unsigned int usable_blks_in_seg = f2fs_usable_blks_in_seg(sbi, segno); + + start_addr = START_BLOCK(sbi, segno); + +next_step: + entry = sum; + + if (fggc && phase == 2) + atomic_inc(&sbi->wb_sync_req[NODE]); + + for (off = 0; off < usable_blks_in_seg; off++, entry++) { + nid_t nid = le32_to_cpu(entry->nid); + struct page *node_page; + struct node_info ni; + int err; + + /* stop BG_GC if there is not enough free sections. */ + if (gc_type == BG_GC && has_not_enough_free_secs(sbi, 0, 0)) + return submitted; + + if (check_valid_map(sbi, segno, off) == 0) + continue; + + if (phase == 0) { + f2fs_ra_meta_pages(sbi, NAT_BLOCK_OFFSET(nid), 1, + META_NAT, true); + continue; + } + + if (phase == 1) { + f2fs_ra_node_page(sbi, nid); + continue; + } + + /* phase == 2 */ + node_page = f2fs_get_node_page(sbi, nid); + if (IS_ERR(node_page)) + continue; + + /* block may become invalid during f2fs_get_node_page */ + if (check_valid_map(sbi, segno, off) == 0) { + f2fs_put_page(node_page, 1); + continue; + } + + if (f2fs_get_node_info(sbi, nid, &ni)) { + f2fs_put_page(node_page, 1); + continue; + } + + if (ni.blk_addr != start_addr + off) { + f2fs_put_page(node_page, 1); + continue; + } + + err = f2fs_move_node_page(node_page, gc_type); + if (!err && gc_type == FG_GC) + submitted++; + stat_inc_node_blk_count(sbi, 1, gc_type); + } + + if (++phase < 3) + goto next_step; + + if (fggc) + atomic_dec(&sbi->wb_sync_req[NODE]); + return submitted; +} + +/* + * Calculate start block index indicating the given node offset. + * Be careful, caller should give this node offset only indicating direct node + * blocks. If any node offsets, which point the other types of node blocks such + * as indirect or double indirect node blocks, are given, it must be a caller's + * bug. + */ +block_t f2fs_start_bidx_of_node(unsigned int node_ofs, struct inode *inode) +{ + unsigned int indirect_blks = 2 * NIDS_PER_BLOCK + 4; + unsigned int bidx; + + if (node_ofs == 0) + return 0; + + if (node_ofs <= 2) { + bidx = node_ofs - 1; + } else if (node_ofs <= indirect_blks) { + int dec = (node_ofs - 4) / (NIDS_PER_BLOCK + 1); + bidx = node_ofs - 2 - dec; + } else { + int dec = (node_ofs - indirect_blks - 3) / (NIDS_PER_BLOCK + 1); + bidx = node_ofs - 5 - dec; + } + return bidx * ADDRS_PER_BLOCK(inode) + ADDRS_PER_INODE(inode); +} + +static bool is_alive(struct f2fs_sb_info *sbi, struct f2fs_summary *sum, + struct node_info *dni, block_t blkaddr, unsigned int *nofs) +{ + struct page *node_page; + nid_t nid; + unsigned int ofs_in_node, max_addrs, base; + block_t source_blkaddr; + + nid = le32_to_cpu(sum->nid); + ofs_in_node = le16_to_cpu(sum->ofs_in_node); + + node_page = f2fs_get_node_page(sbi, nid); + if (IS_ERR(node_page)) + return false; + + if (f2fs_get_node_info(sbi, nid, dni)) { + f2fs_put_page(node_page, 1); + return false; + } + + if (sum->version != dni->version) { + f2fs_warn(sbi, "%s: valid data with mismatched node version.", + __func__); + set_sbi_flag(sbi, SBI_NEED_FSCK); + } + + if (f2fs_check_nid_range(sbi, dni->ino)) { + f2fs_put_page(node_page, 1); + return false; + } + + if (IS_INODE(node_page)) { + base = offset_in_addr(F2FS_INODE(node_page)); + max_addrs = DEF_ADDRS_PER_INODE; + } else { + base = 0; + max_addrs = DEF_ADDRS_PER_BLOCK; + } + + if (base + ofs_in_node >= max_addrs) { + f2fs_err(sbi, "Inconsistent blkaddr offset: base:%u, ofs_in_node:%u, max:%u, ino:%u, nid:%u", + base, ofs_in_node, max_addrs, dni->ino, dni->nid); + f2fs_put_page(node_page, 1); + return false; + } + + *nofs = ofs_of_node(node_page); + source_blkaddr = data_blkaddr(NULL, node_page, ofs_in_node); + f2fs_put_page(node_page, 1); + + if (source_blkaddr != blkaddr) { +#ifdef CONFIG_F2FS_CHECK_FS + unsigned int segno = GET_SEGNO(sbi, blkaddr); + unsigned long offset = GET_BLKOFF_FROM_SEG0(sbi, blkaddr); + + if (unlikely(check_valid_map(sbi, segno, offset))) { + if (!test_and_set_bit(segno, SIT_I(sbi)->invalid_segmap)) { + f2fs_err(sbi, "mismatched blkaddr %u (source_blkaddr %u) in seg %u\n", + blkaddr, source_blkaddr, segno); + f2fs_bug_on(sbi, 1); + } + } +#endif + return false; + } + return true; +} + +static int ra_data_block(struct inode *inode, pgoff_t index) +{ + struct f2fs_sb_info *sbi = F2FS_I_SB(inode); + struct address_space *mapping = inode->i_mapping; + struct dnode_of_data dn; + struct page *page; + struct extent_info ei = {0, 0, 0}; + struct f2fs_io_info fio = { + .sbi = sbi, + .ino = inode->i_ino, + .type = DATA, + .temp = COLD, + .op = REQ_OP_READ, + .op_flags = 0, + .encrypted_page = NULL, + .in_list = false, + .retry = false, + }; + int err; + + page = f2fs_grab_cache_page(mapping, index, true); + if (!page) + return -ENOMEM; + + if (f2fs_lookup_extent_cache(inode, index, &ei)) { + dn.data_blkaddr = ei.blk + index - ei.fofs; + if (unlikely(!f2fs_is_valid_blkaddr(sbi, dn.data_blkaddr, + DATA_GENERIC_ENHANCE_READ))) { + err = -EFSCORRUPTED; + goto put_page; + } + goto got_it; + } + + set_new_dnode(&dn, inode, NULL, NULL, 0); + err = f2fs_get_dnode_of_data(&dn, index, LOOKUP_NODE); + if (err) + goto put_page; + f2fs_put_dnode(&dn); + + if (!__is_valid_data_blkaddr(dn.data_blkaddr)) { + err = -ENOENT; + goto put_page; + } + if (unlikely(!f2fs_is_valid_blkaddr(sbi, dn.data_blkaddr, + DATA_GENERIC_ENHANCE))) { + err = -EFSCORRUPTED; + goto put_page; + } +got_it: + /* read page */ + fio.page = page; + fio.new_blkaddr = fio.old_blkaddr = dn.data_blkaddr; + + /* + * don't cache encrypted data into meta inode until previous dirty + * data were writebacked to avoid racing between GC and flush. + */ + f2fs_wait_on_page_writeback(page, DATA, true, true); + + f2fs_wait_on_block_writeback(inode, dn.data_blkaddr); + + fio.encrypted_page = f2fs_pagecache_get_page(META_MAPPING(sbi), + dn.data_blkaddr, + FGP_LOCK | FGP_CREAT, GFP_NOFS); + if (!fio.encrypted_page) { + err = -ENOMEM; + goto put_page; + } + + err = f2fs_submit_page_bio(&fio); + if (err) + goto put_encrypted_page; + f2fs_put_page(fio.encrypted_page, 0); + f2fs_put_page(page, 1); + + f2fs_update_iostat(sbi, FS_DATA_READ_IO, F2FS_BLKSIZE); + f2fs_update_iostat(sbi, FS_GDATA_READ_IO, F2FS_BLKSIZE); + + return 0; +put_encrypted_page: + f2fs_put_page(fio.encrypted_page, 1); +put_page: + f2fs_put_page(page, 1); + return err; +} + +/* + * Move data block via META_MAPPING while keeping locked data page. + * This can be used to move blocks, aka LBAs, directly on disk. + */ +static int move_data_block(struct inode *inode, block_t bidx, + int gc_type, unsigned int segno, int off) +{ + struct f2fs_io_info fio = { + .sbi = F2FS_I_SB(inode), + .ino = inode->i_ino, + .type = DATA, + .temp = COLD, + .op = REQ_OP_READ, + .op_flags = 0, + .encrypted_page = NULL, + .in_list = false, + .retry = false, + }; + struct dnode_of_data dn; + struct f2fs_summary sum; + struct node_info ni; + struct page *page, *mpage; + block_t newaddr; + int err = 0; + bool lfs_mode = f2fs_lfs_mode(fio.sbi); + int type = fio.sbi->am.atgc_enabled ? + CURSEG_ALL_DATA_ATGC : CURSEG_COLD_DATA; + + /* do not read out */ + page = f2fs_grab_cache_page(inode->i_mapping, bidx, false); + if (!page) + return -ENOMEM; + + if (!check_valid_map(F2FS_I_SB(inode), segno, off)) { + err = -ENOENT; + goto out; + } + + if (f2fs_is_atomic_file(inode)) { + F2FS_I(inode)->i_gc_failures[GC_FAILURE_ATOMIC]++; + F2FS_I_SB(inode)->skipped_atomic_files[gc_type]++; + err = -EAGAIN; + goto out; + } + + if (f2fs_is_pinned_file(inode)) { + if (gc_type == FG_GC) + f2fs_pin_file_control(inode, true); + err = -EAGAIN; + goto out; + } + + set_new_dnode(&dn, inode, NULL, NULL, 0); + err = f2fs_get_dnode_of_data(&dn, bidx, LOOKUP_NODE); + if (err) + goto out; + + if (unlikely(dn.data_blkaddr == NULL_ADDR)) { + ClearPageUptodate(page); + err = -ENOENT; + goto put_out; + } + + /* + * don't cache encrypted data into meta inode until previous dirty + * data were writebacked to avoid racing between GC and flush. + */ + f2fs_wait_on_page_writeback(page, DATA, true, true); + + f2fs_wait_on_block_writeback(inode, dn.data_blkaddr); + + err = f2fs_get_node_info(fio.sbi, dn.nid, &ni); + if (err) + goto put_out; + + set_summary(&sum, dn.nid, dn.ofs_in_node, ni.version); + + /* read page */ + fio.page = page; + fio.new_blkaddr = fio.old_blkaddr = dn.data_blkaddr; + + if (lfs_mode) + down_write(&fio.sbi->io_order_lock); + + mpage = f2fs_grab_cache_page(META_MAPPING(fio.sbi), + fio.old_blkaddr, false); + if (!mpage) { + err = -ENOMEM; + goto up_out; + } + + fio.encrypted_page = mpage; + + /* read source block in mpage */ + if (!PageUptodate(mpage)) { + err = f2fs_submit_page_bio(&fio); + if (err) { + f2fs_put_page(mpage, 1); + goto up_out; + } + + f2fs_update_iostat(fio.sbi, FS_DATA_READ_IO, F2FS_BLKSIZE); + f2fs_update_iostat(fio.sbi, FS_GDATA_READ_IO, F2FS_BLKSIZE); + + lock_page(mpage); + if (unlikely(mpage->mapping != META_MAPPING(fio.sbi) || + !PageUptodate(mpage))) { + err = -EIO; + f2fs_put_page(mpage, 1); + goto up_out; + } + } + + f2fs_allocate_data_block(fio.sbi, NULL, fio.old_blkaddr, &newaddr, + &sum, type, NULL); + + fio.encrypted_page = f2fs_pagecache_get_page(META_MAPPING(fio.sbi), + newaddr, FGP_LOCK | FGP_CREAT, GFP_NOFS); + if (!fio.encrypted_page) { + err = -ENOMEM; + f2fs_put_page(mpage, 1); + goto recover_block; + } + + /* write target block */ + f2fs_wait_on_page_writeback(fio.encrypted_page, DATA, true, true); + memcpy(page_address(fio.encrypted_page), + page_address(mpage), PAGE_SIZE); + f2fs_put_page(mpage, 1); + invalidate_mapping_pages(META_MAPPING(fio.sbi), + fio.old_blkaddr, fio.old_blkaddr); + + set_page_dirty(fio.encrypted_page); + if (clear_page_dirty_for_io(fio.encrypted_page)) + dec_page_count(fio.sbi, F2FS_DIRTY_META); + + set_page_writeback(fio.encrypted_page); + ClearPageError(page); + + /* allocate block address */ + f2fs_wait_on_page_writeback(dn.node_page, NODE, true, true); + + fio.op = REQ_OP_WRITE; + fio.op_flags = REQ_SYNC; + fio.new_blkaddr = newaddr; + f2fs_submit_page_write(&fio); + if (fio.retry) { + err = -EAGAIN; + if (PageWriteback(fio.encrypted_page)) + end_page_writeback(fio.encrypted_page); + goto put_page_out; + } + + f2fs_update_iostat(fio.sbi, FS_GC_DATA_IO, F2FS_BLKSIZE); + + f2fs_update_data_blkaddr(&dn, newaddr); + set_inode_flag(inode, FI_APPEND_WRITE); + if (page->index == 0) + set_inode_flag(inode, FI_FIRST_BLOCK_WRITTEN); +put_page_out: + f2fs_put_page(fio.encrypted_page, 1); +recover_block: + if (err) + f2fs_do_replace_block(fio.sbi, &sum, newaddr, fio.old_blkaddr, + true, true, true); +up_out: + if (lfs_mode) + up_write(&fio.sbi->io_order_lock); +put_out: + f2fs_put_dnode(&dn); +out: + f2fs_put_page(page, 1); + return err; +} + +static int move_data_page(struct inode *inode, block_t bidx, int gc_type, + unsigned int segno, int off) +{ + struct page *page; + int err = 0; + + page = f2fs_get_lock_data_page(inode, bidx, true); + if (IS_ERR(page)) + return PTR_ERR(page); + + if (!check_valid_map(F2FS_I_SB(inode), segno, off)) { + err = -ENOENT; + goto out; + } + + if (f2fs_is_atomic_file(inode)) { + F2FS_I(inode)->i_gc_failures[GC_FAILURE_ATOMIC]++; + F2FS_I_SB(inode)->skipped_atomic_files[gc_type]++; + err = -EAGAIN; + goto out; + } + if (f2fs_is_pinned_file(inode)) { + if (gc_type == FG_GC) + f2fs_pin_file_control(inode, true); + err = -EAGAIN; + goto out; + } + + if (gc_type == BG_GC) { + if (PageWriteback(page)) { + err = -EAGAIN; + goto out; + } + set_page_dirty(page); + set_cold_data(page); + } else { + struct f2fs_io_info fio = { + .sbi = F2FS_I_SB(inode), + .ino = inode->i_ino, + .type = DATA, + .temp = COLD, + .op = REQ_OP_WRITE, + .op_flags = REQ_SYNC, + .old_blkaddr = NULL_ADDR, + .page = page, + .encrypted_page = NULL, + .need_lock = LOCK_REQ, + .io_type = FS_GC_DATA_IO, + }; + bool is_dirty = PageDirty(page); + +retry: + f2fs_wait_on_page_writeback(page, DATA, true, true); + + set_page_dirty(page); + if (clear_page_dirty_for_io(page)) { + inode_dec_dirty_pages(inode); + f2fs_remove_dirty_inode(inode); + } + + set_cold_data(page); + + err = f2fs_do_write_data_page(&fio); + if (err) { + clear_cold_data(page); + if (err == -ENOMEM) { + congestion_wait(BLK_RW_ASYNC, + DEFAULT_IO_TIMEOUT); + goto retry; + } + if (is_dirty) + set_page_dirty(page); + } + } +out: + f2fs_put_page(page, 1); + return err; +} + +/* + * This function tries to get parent node of victim data block, and identifies + * data block validity. If the block is valid, copy that with cold status and + * modify parent node. + * If the parent node is not valid or the data block address is different, + * the victim data block is ignored. + */ +static int gc_data_segment(struct f2fs_sb_info *sbi, struct f2fs_summary *sum, + struct gc_inode_list *gc_list, unsigned int segno, int gc_type, + bool force_migrate) +{ + struct super_block *sb = sbi->sb; + struct f2fs_summary *entry; + block_t start_addr; + int off; + int phase = 0; + int submitted = 0; + unsigned int usable_blks_in_seg = f2fs_usable_blks_in_seg(sbi, segno); + + start_addr = START_BLOCK(sbi, segno); + +next_step: + entry = sum; + + for (off = 0; off < usable_blks_in_seg; off++, entry++) { + struct page *data_page; + struct inode *inode; + struct node_info dni; /* dnode info for the data */ + unsigned int ofs_in_node, nofs; + block_t start_bidx; + nid_t nid = le32_to_cpu(entry->nid); + + /* + * stop BG_GC if there is not enough free sections. + * Or, stop GC if the segment becomes fully valid caused by + * race condition along with SSR block allocation. + */ + if ((gc_type == BG_GC && has_not_enough_free_secs(sbi, 0, 0)) || + (!force_migrate && get_valid_blocks(sbi, segno, true) == + BLKS_PER_SEC(sbi))) + return submitted; + + if (check_valid_map(sbi, segno, off) == 0) + continue; + + if (phase == 0) { + f2fs_ra_meta_pages(sbi, NAT_BLOCK_OFFSET(nid), 1, + META_NAT, true); + continue; + } + + if (phase == 1) { + f2fs_ra_node_page(sbi, nid); + continue; + } + + /* Get an inode by ino with checking validity */ + if (!is_alive(sbi, entry, &dni, start_addr + off, &nofs)) + continue; + + if (phase == 2) { + f2fs_ra_node_page(sbi, dni.ino); + continue; + } + + ofs_in_node = le16_to_cpu(entry->ofs_in_node); + + if (phase == 3) { + inode = f2fs_iget(sb, dni.ino); + if (IS_ERR(inode) || is_bad_inode(inode) || + special_file(inode->i_mode)) { + set_sbi_flag(sbi, SBI_NEED_FSCK); + continue; + } + + if (!down_write_trylock( + &F2FS_I(inode)->i_gc_rwsem[WRITE])) { + iput(inode); + sbi->skipped_gc_rwsem++; + continue; + } + + start_bidx = f2fs_start_bidx_of_node(nofs, inode) + + ofs_in_node; + + if (f2fs_post_read_required(inode)) { + int err = ra_data_block(inode, start_bidx); + + up_write(&F2FS_I(inode)->i_gc_rwsem[WRITE]); + if (err) { + iput(inode); + continue; + } + add_gc_inode(gc_list, inode); + continue; + } + + data_page = f2fs_get_read_data_page(inode, + start_bidx, REQ_RAHEAD, true); + up_write(&F2FS_I(inode)->i_gc_rwsem[WRITE]); + if (IS_ERR(data_page)) { + iput(inode); + continue; + } + + f2fs_put_page(data_page, 0); + add_gc_inode(gc_list, inode); + continue; + } + + /* phase 4 */ + inode = find_gc_inode(gc_list, dni.ino); + if (inode) { + struct f2fs_inode_info *fi = F2FS_I(inode); + bool locked = false; + int err; + + if (S_ISREG(inode->i_mode)) { + if (!down_write_trylock(&fi->i_gc_rwsem[READ])) { + sbi->skipped_gc_rwsem++; + continue; + } + if (!down_write_trylock( + &fi->i_gc_rwsem[WRITE])) { + sbi->skipped_gc_rwsem++; + up_write(&fi->i_gc_rwsem[READ]); + continue; + } + locked = true; + + /* wait for all inflight aio data */ + inode_dio_wait(inode); + } + + start_bidx = f2fs_start_bidx_of_node(nofs, inode) + + ofs_in_node; + if (f2fs_post_read_required(inode)) + err = move_data_block(inode, start_bidx, + gc_type, segno, off); + else + err = move_data_page(inode, start_bidx, gc_type, + segno, off); + + if (!err && (gc_type == FG_GC || + f2fs_post_read_required(inode))) + submitted++; + + if (locked) { + up_write(&fi->i_gc_rwsem[WRITE]); + up_write(&fi->i_gc_rwsem[READ]); + } + + stat_inc_data_blk_count(sbi, 1, gc_type); + } + } + + if (++phase < 5) + goto next_step; + + return submitted; +} + +static int __get_victim(struct f2fs_sb_info *sbi, unsigned int *victim, + int gc_type) +{ + struct sit_info *sit_i = SIT_I(sbi); + int ret; + + down_write(&sit_i->sentry_lock); + ret = DIRTY_I(sbi)->v_ops->get_victim(sbi, victim, gc_type, + NO_CHECK_TYPE, LFS, 0); + up_write(&sit_i->sentry_lock); + return ret; +} + +static int do_garbage_collect(struct f2fs_sb_info *sbi, + unsigned int start_segno, + struct gc_inode_list *gc_list, int gc_type, + bool force_migrate) +{ + struct page *sum_page; + struct f2fs_summary_block *sum; + struct blk_plug plug; + unsigned int segno = start_segno; + unsigned int end_segno = start_segno + sbi->segs_per_sec; + int seg_freed = 0, migrated = 0; + unsigned char type = IS_DATASEG(get_seg_entry(sbi, segno)->type) ? + SUM_TYPE_DATA : SUM_TYPE_NODE; + int submitted = 0; + + if (__is_large_section(sbi)) + end_segno = rounddown(end_segno, sbi->segs_per_sec); + + /* + * zone-capacity can be less than zone-size in zoned devices, + * resulting in less than expected usable segments in the zone, + * calculate the end segno in the zone which can be garbage collected + */ + if (f2fs_sb_has_blkzoned(sbi)) + end_segno -= sbi->segs_per_sec - + f2fs_usable_segs_in_sec(sbi, segno); + + sanity_check_seg_type(sbi, get_seg_entry(sbi, segno)->type); + + /* readahead multi ssa blocks those have contiguous address */ + if (__is_large_section(sbi)) + f2fs_ra_meta_pages(sbi, GET_SUM_BLOCK(sbi, segno), + end_segno - segno, META_SSA, true); + + /* reference all summary page */ + while (segno < end_segno) { + sum_page = f2fs_get_sum_page(sbi, segno++); + if (IS_ERR(sum_page)) { + int err = PTR_ERR(sum_page); + + end_segno = segno - 1; + for (segno = start_segno; segno < end_segno; segno++) { + sum_page = find_get_page(META_MAPPING(sbi), + GET_SUM_BLOCK(sbi, segno)); + f2fs_put_page(sum_page, 0); + f2fs_put_page(sum_page, 0); + } + return err; + } + unlock_page(sum_page); + } + + blk_start_plug(&plug); + + for (segno = start_segno; segno < end_segno; segno++) { + + /* find segment summary of victim */ + sum_page = find_get_page(META_MAPPING(sbi), + GET_SUM_BLOCK(sbi, segno)); + f2fs_put_page(sum_page, 0); + + if (get_valid_blocks(sbi, segno, false) == 0) + goto freed; + if (gc_type == BG_GC && __is_large_section(sbi) && + migrated >= sbi->migration_granularity) + goto skip; + if (!PageUptodate(sum_page) || unlikely(f2fs_cp_error(sbi))) + goto skip; + + sum = page_address(sum_page); + if (type != GET_SUM_TYPE((&sum->footer))) { + f2fs_err(sbi, "Inconsistent segment (%u) type [%d, %d] in SSA and SIT", + segno, type, GET_SUM_TYPE((&sum->footer))); + set_sbi_flag(sbi, SBI_NEED_FSCK); + f2fs_stop_checkpoint(sbi, false); + goto skip; + } + + /* + * this is to avoid deadlock: + * - lock_page(sum_page) - f2fs_replace_block + * - check_valid_map() - down_write(sentry_lock) + * - down_read(sentry_lock) - change_curseg() + * - lock_page(sum_page) + */ + if (type == SUM_TYPE_NODE) + submitted += gc_node_segment(sbi, sum->entries, segno, + gc_type); + else + submitted += gc_data_segment(sbi, sum->entries, gc_list, + segno, gc_type, + force_migrate); + + stat_inc_seg_count(sbi, type, gc_type); + migrated++; + +freed: + if (gc_type == FG_GC && + get_valid_blocks(sbi, segno, false) == 0) + seg_freed++; + + if (__is_large_section(sbi)) + sbi->next_victim_seg[gc_type] = + (segno + 1 < end_segno) ? segno + 1 : NULL_SEGNO; +skip: + f2fs_put_page(sum_page, 0); + } + + if (submitted) + f2fs_submit_merged_write(sbi, + (type == SUM_TYPE_NODE) ? NODE : DATA); + + blk_finish_plug(&plug); + + stat_inc_call_count(sbi->stat_info); + + return seg_freed; +} + +int f2fs_gc(struct f2fs_sb_info *sbi, bool sync, + bool background, bool force, unsigned int segno) +{ + int gc_type = sync ? FG_GC : BG_GC; + int sec_freed = 0, seg_freed = 0, total_freed = 0; + int ret = 0; + struct cp_control cpc; + unsigned int init_segno = segno; + struct gc_inode_list gc_list = { + .ilist = LIST_HEAD_INIT(gc_list.ilist), + .iroot = RADIX_TREE_INIT(gc_list.iroot, GFP_NOFS), + }; + unsigned long long last_skipped = sbi->skipped_atomic_files[FG_GC]; + unsigned long long first_skipped; + unsigned int skipped_round = 0, round = 0; + + trace_f2fs_gc_begin(sbi->sb, sync, background, + get_pages(sbi, F2FS_DIRTY_NODES), + get_pages(sbi, F2FS_DIRTY_DENTS), + get_pages(sbi, F2FS_DIRTY_IMETA), + free_sections(sbi), + free_segments(sbi), + reserved_segments(sbi), + prefree_segments(sbi)); + + cpc.reason = __get_cp_reason(sbi); + sbi->skipped_gc_rwsem = 0; + first_skipped = last_skipped; +gc_more: + if (unlikely(!(sbi->sb->s_flags & SB_ACTIVE))) { + ret = -EINVAL; + goto stop; + } + if (unlikely(f2fs_cp_error(sbi))) { + ret = -EIO; + goto stop; + } + + if (gc_type == BG_GC && has_not_enough_free_secs(sbi, 0, 0)) { + /* + * For example, if there are many prefree_segments below given + * threshold, we can make them free by checkpoint. Then, we + * secure free segments which doesn't need fggc any more. + */ + if (prefree_segments(sbi) && + !is_sbi_flag_set(sbi, SBI_CP_DISABLED)) { + ret = f2fs_write_checkpoint(sbi, &cpc); + if (ret) + goto stop; + } + if (has_not_enough_free_secs(sbi, 0, 0)) + gc_type = FG_GC; + } + + /* f2fs_balance_fs doesn't need to do BG_GC in critical path. */ + if (gc_type == BG_GC && !background) { + ret = -EINVAL; + goto stop; + } + ret = __get_victim(sbi, &segno, gc_type); + if (ret) + goto stop; + + seg_freed = do_garbage_collect(sbi, segno, &gc_list, gc_type, force); + if (gc_type == FG_GC && + seg_freed == f2fs_usable_segs_in_sec(sbi, segno)) + sec_freed++; + total_freed += seg_freed; + + if (gc_type == FG_GC) { + if (sbi->skipped_atomic_files[FG_GC] > last_skipped || + sbi->skipped_gc_rwsem) + skipped_round++; + last_skipped = sbi->skipped_atomic_files[FG_GC]; + round++; + } + + if (gc_type == FG_GC && seg_freed) + sbi->cur_victim_sec = NULL_SEGNO; + + if (sync) + goto stop; + + if (!has_not_enough_free_secs(sbi, sec_freed, 0)) + goto stop; + + if (skipped_round <= MAX_SKIP_GC_COUNT || skipped_round * 2 < round) { + + /* Write checkpoint to reclaim prefree segments */ + if (free_sections(sbi) < NR_CURSEG_PERSIST_TYPE && + prefree_segments(sbi) && + !is_sbi_flag_set(sbi, SBI_CP_DISABLED)) { + ret = f2fs_write_checkpoint(sbi, &cpc); + if (ret) + goto stop; + } + segno = NULL_SEGNO; + goto gc_more; + } + if (first_skipped < last_skipped && + (last_skipped - first_skipped) > + sbi->skipped_gc_rwsem) { + f2fs_drop_inmem_pages_all(sbi, true); + segno = NULL_SEGNO; + goto gc_more; + } + if (gc_type == FG_GC && !is_sbi_flag_set(sbi, SBI_CP_DISABLED)) + ret = f2fs_write_checkpoint(sbi, &cpc); +stop: + SIT_I(sbi)->last_victim[ALLOC_NEXT] = 0; + SIT_I(sbi)->last_victim[FLUSH_DEVICE] = init_segno; + + trace_f2fs_gc_end(sbi->sb, ret, total_freed, sec_freed, + get_pages(sbi, F2FS_DIRTY_NODES), + get_pages(sbi, F2FS_DIRTY_DENTS), + get_pages(sbi, F2FS_DIRTY_IMETA), + free_sections(sbi), + free_segments(sbi), + reserved_segments(sbi), + prefree_segments(sbi)); + + up_write(&sbi->gc_lock); + + put_gc_inode(&gc_list); + + if (sync && !ret) + ret = sec_freed ? 0 : -EAGAIN; + return ret; +} + +int __init f2fs_create_garbage_collection_cache(void) +{ + victim_entry_slab = f2fs_kmem_cache_create("f2fs_victim_entry", + sizeof(struct victim_entry)); + if (!victim_entry_slab) + return -ENOMEM; + return 0; +} + +void f2fs_destroy_garbage_collection_cache(void) +{ + kmem_cache_destroy(victim_entry_slab); +} + +static void init_atgc_management(struct f2fs_sb_info *sbi) +{ + struct atgc_management *am = &sbi->am; + + if (test_opt(sbi, ATGC) && + SIT_I(sbi)->elapsed_time >= DEF_GC_THREAD_AGE_THRESHOLD) + am->atgc_enabled = true; + + am->root = RB_ROOT_CACHED; + INIT_LIST_HEAD(&am->victim_list); + am->victim_count = 0; + + am->candidate_ratio = DEF_GC_THREAD_CANDIDATE_RATIO; + am->max_candidate_count = DEF_GC_THREAD_MAX_CANDIDATE_COUNT; + am->age_weight = DEF_GC_THREAD_AGE_WEIGHT; + am->age_threshold = DEF_GC_THREAD_AGE_THRESHOLD; +} + +void f2fs_build_gc_manager(struct f2fs_sb_info *sbi) +{ + DIRTY_I(sbi)->v_ops = &default_v_ops; + + sbi->gc_pin_file_threshold = DEF_GC_FAILED_PINNED_FILES; + + /* give warm/cold data area from slower device */ + if (f2fs_is_multi_device(sbi) && !__is_large_section(sbi)) + SIT_I(sbi)->last_victim[ALLOC_NEXT] = + GET_SEGNO(sbi, FDEV(0).end_blk) + 1; + + init_atgc_management(sbi); +} + +static int free_segment_range(struct f2fs_sb_info *sbi, + unsigned int secs, bool gc_only) +{ + unsigned int segno, next_inuse, start, end; + struct cp_control cpc = { CP_RESIZE, 0, 0, 0 }; + int gc_mode, gc_type; + int err = 0; + int type; + + /* Force block allocation for GC */ + MAIN_SECS(sbi) -= secs; + start = MAIN_SECS(sbi) * sbi->segs_per_sec; + end = MAIN_SEGS(sbi) - 1; + + mutex_lock(&DIRTY_I(sbi)->seglist_lock); + for (gc_mode = 0; gc_mode < MAX_GC_POLICY; gc_mode++) + if (SIT_I(sbi)->last_victim[gc_mode] >= start) + SIT_I(sbi)->last_victim[gc_mode] = 0; + + for (gc_type = BG_GC; gc_type <= FG_GC; gc_type++) + if (sbi->next_victim_seg[gc_type] >= start) + sbi->next_victim_seg[gc_type] = NULL_SEGNO; + mutex_unlock(&DIRTY_I(sbi)->seglist_lock); + + /* Move out cursegs from the target range */ + for (type = CURSEG_HOT_DATA; type < NR_CURSEG_PERSIST_TYPE; type++) + f2fs_allocate_segment_for_resize(sbi, type, start, end); + + /* do GC to move out valid blocks in the range */ + for (segno = start; segno <= end; segno += sbi->segs_per_sec) { + struct gc_inode_list gc_list = { + .ilist = LIST_HEAD_INIT(gc_list.ilist), + .iroot = RADIX_TREE_INIT(gc_list.iroot, GFP_NOFS), + }; + + do_garbage_collect(sbi, segno, &gc_list, FG_GC, true); + put_gc_inode(&gc_list); + + if (!gc_only && get_valid_blocks(sbi, segno, true)) { + err = -EAGAIN; + goto out; + } + if (fatal_signal_pending(current)) { + err = -ERESTARTSYS; + goto out; + } + } + if (gc_only) + goto out; + + err = f2fs_write_checkpoint(sbi, &cpc); + if (err) + goto out; + + next_inuse = find_next_inuse(FREE_I(sbi), end + 1, start); + if (next_inuse <= end) { + f2fs_err(sbi, "segno %u should be free but still inuse!", + next_inuse); + f2fs_bug_on(sbi, 1); + } +out: + MAIN_SECS(sbi) += secs; + return err; +} + +static void update_sb_metadata(struct f2fs_sb_info *sbi, int secs) +{ + struct f2fs_super_block *raw_sb = F2FS_RAW_SUPER(sbi); + int section_count; + int segment_count; + int segment_count_main; + long long block_count; + int segs = secs * sbi->segs_per_sec; + + down_write(&sbi->sb_lock); + + section_count = le32_to_cpu(raw_sb->section_count); + segment_count = le32_to_cpu(raw_sb->segment_count); + segment_count_main = le32_to_cpu(raw_sb->segment_count_main); + block_count = le64_to_cpu(raw_sb->block_count); + + raw_sb->section_count = cpu_to_le32(section_count + secs); + raw_sb->segment_count = cpu_to_le32(segment_count + segs); + raw_sb->segment_count_main = cpu_to_le32(segment_count_main + segs); + raw_sb->block_count = cpu_to_le64(block_count + + (long long)segs * sbi->blocks_per_seg); + if (f2fs_is_multi_device(sbi)) { + int last_dev = sbi->s_ndevs - 1; + int dev_segs = + le32_to_cpu(raw_sb->devs[last_dev].total_segments); + + raw_sb->devs[last_dev].total_segments = + cpu_to_le32(dev_segs + segs); + } + + up_write(&sbi->sb_lock); +} + +static void update_fs_metadata(struct f2fs_sb_info *sbi, int secs) +{ + int segs = secs * sbi->segs_per_sec; + long long blks = (long long)segs * sbi->blocks_per_seg; + long long user_block_count = + le64_to_cpu(F2FS_CKPT(sbi)->user_block_count); + + SM_I(sbi)->segment_count = (int)SM_I(sbi)->segment_count + segs; + MAIN_SEGS(sbi) = (int)MAIN_SEGS(sbi) + segs; + MAIN_SECS(sbi) += secs; + FREE_I(sbi)->free_sections = (int)FREE_I(sbi)->free_sections + secs; + FREE_I(sbi)->free_segments = (int)FREE_I(sbi)->free_segments + segs; + F2FS_CKPT(sbi)->user_block_count = cpu_to_le64(user_block_count + blks); + + if (f2fs_is_multi_device(sbi)) { + int last_dev = sbi->s_ndevs - 1; + + FDEV(last_dev).total_segments = + (int)FDEV(last_dev).total_segments + segs; + FDEV(last_dev).end_blk = + (long long)FDEV(last_dev).end_blk + blks; +#ifdef CONFIG_BLK_DEV_ZONED + FDEV(last_dev).nr_blkz = (int)FDEV(last_dev).nr_blkz + + (int)(blks >> sbi->log_blocks_per_blkz); +#endif + } +} + +int f2fs_resize_fs(struct file *filp, __u64 block_count) +{ + struct f2fs_sb_info *sbi = F2FS_I_SB(file_inode(filp)); + __u64 old_block_count, shrunk_blocks; + struct cp_control cpc = { CP_RESIZE, 0, 0, 0 }; + unsigned int secs; + int err = 0; + __u32 rem; + + old_block_count = le64_to_cpu(F2FS_RAW_SUPER(sbi)->block_count); + if (block_count > old_block_count) + return -EINVAL; + + if (f2fs_is_multi_device(sbi)) { + int last_dev = sbi->s_ndevs - 1; + __u64 last_segs = FDEV(last_dev).total_segments; + + if (block_count + last_segs * sbi->blocks_per_seg <= + old_block_count) + return -EINVAL; + } + + /* new fs size should align to section size */ + div_u64_rem(block_count, BLKS_PER_SEC(sbi), &rem); + if (rem) + return -EINVAL; + + if (block_count == old_block_count) + return 0; + + if (is_sbi_flag_set(sbi, SBI_NEED_FSCK)) { + f2fs_err(sbi, "Should run fsck to repair first."); + return -EFSCORRUPTED; + } + + if (test_opt(sbi, DISABLE_CHECKPOINT)) { + f2fs_err(sbi, "Checkpoint should be enabled."); + return -EINVAL; + } + + err = mnt_want_write_file(filp); + if (err) + return err; + + shrunk_blocks = old_block_count - block_count; + secs = div_u64(shrunk_blocks, BLKS_PER_SEC(sbi)); + + /* stop other GC */ + if (!down_write_trylock(&sbi->gc_lock)) { + err = -EAGAIN; + goto out_drop_write; + } + + /* stop CP to protect MAIN_SEC in free_segment_range */ + f2fs_lock_op(sbi); + + spin_lock(&sbi->stat_lock); + if (shrunk_blocks + valid_user_blocks(sbi) + + sbi->current_reserved_blocks + sbi->unusable_block_count + + F2FS_OPTION(sbi).root_reserved_blocks > sbi->user_block_count) + err = -ENOSPC; + spin_unlock(&sbi->stat_lock); + + if (err) + goto out_unlock; + + err = free_segment_range(sbi, secs, true); + +out_unlock: + f2fs_unlock_op(sbi); + up_write(&sbi->gc_lock); +out_drop_write: + mnt_drop_write_file(filp); + if (err) + return err; + + freeze_super(sbi->sb); + + if (f2fs_readonly(sbi->sb)) { + thaw_super(sbi->sb); + return -EROFS; + } + + down_write(&sbi->gc_lock); + mutex_lock(&sbi->cp_mutex); + + spin_lock(&sbi->stat_lock); + if (shrunk_blocks + valid_user_blocks(sbi) + + sbi->current_reserved_blocks + sbi->unusable_block_count + + F2FS_OPTION(sbi).root_reserved_blocks > sbi->user_block_count) + err = -ENOSPC; + else + sbi->user_block_count -= shrunk_blocks; + spin_unlock(&sbi->stat_lock); + if (err) + goto out_err; + + set_sbi_flag(sbi, SBI_IS_RESIZEFS); + err = free_segment_range(sbi, secs, false); + if (err) + goto recover_out; + + update_sb_metadata(sbi, -secs); + + err = f2fs_commit_super(sbi, false); + if (err) { + update_sb_metadata(sbi, secs); + goto recover_out; + } + + update_fs_metadata(sbi, -secs); + clear_sbi_flag(sbi, SBI_IS_RESIZEFS); + set_sbi_flag(sbi, SBI_IS_DIRTY); + + err = f2fs_write_checkpoint(sbi, &cpc); + if (err) { + update_fs_metadata(sbi, secs); + update_sb_metadata(sbi, secs); + f2fs_commit_super(sbi, false); + } +recover_out: + clear_sbi_flag(sbi, SBI_IS_RESIZEFS); + if (err) { + set_sbi_flag(sbi, SBI_NEED_FSCK); + f2fs_err(sbi, "resize_fs failed, should run fsck to repair!"); + + spin_lock(&sbi->stat_lock); + sbi->user_block_count += shrunk_blocks; + spin_unlock(&sbi->stat_lock); + } +out_err: + mutex_unlock(&sbi->cp_mutex); + up_write(&sbi->gc_lock); + thaw_super(sbi->sb); + return err; +} |