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android-kvm / linux / refs/heads/analysis/uart / . / fs / f2fs / gc.c
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// 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/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 <linux/random.h>
#include "f2fs.h"
#include "node.h"
#include "segment.h"
#include "gc.h"
#include "iostat.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;
wait_queue_head_t *fggc_wq = &sbi->gc_thread->fggc_wq;
unsigned int wait_ms;
struct f2fs_gc_control gc_control = {
.victim_segno = NULL_SEGNO,
.should_migrate_blocks = false,
.err_gc_skipped = false };
wait_ms = gc_th->min_sleep_time;
set_freezable();
do {
bool sync_mode, foreground = false;
wait_event_interruptible_timeout(*wq,
kthread_should_stop() || freezing(current) ||
waitqueue_active(fggc_wq) ||
gc_th->gc_wake,
msecs_to_jiffies(wait_ms));
if (test_opt(sbi, GC_MERGE) && waitqueue_active(fggc_wq))
foreground = true;
/* 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,
STOP_CP_REASON_FAULT_INJECT);
}
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 ||
sbi->gc_mode == GC_URGENT_MID) {
wait_ms = gc_th->urgent_sleep_time;
f2fs_down_write(&sbi->gc_lock);
goto do_gc;
}
if (foreground) {
f2fs_down_write(&sbi->gc_lock);
goto do_gc;
} else if (!f2fs_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);
f2fs_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:
if (!foreground)
stat_inc_bggc_count(sbi->stat_info);
sync_mode = F2FS_OPTION(sbi).bggc_mode == BGGC_MODE_SYNC;
/* foreground GC was been triggered via f2fs_balance_fs() */
if (foreground)
sync_mode = false;
gc_control.init_gc_type = sync_mode ? FG_GC : BG_GC;
gc_control.no_bg_gc = foreground;
gc_control.nr_free_secs = foreground ? 1 : 0;
/* if return value is not zero, no victim was selected */
if (f2fs_gc(sbi, &gc_control)) {
/* don't bother wait_ms by foreground gc */
if (!foreground)
wait_ms = gc_th->no_gc_sleep_time;
} else {
/* reset wait_ms to default sleep time */
if (wait_ms == gc_th->no_gc_sleep_time)
wait_ms = gc_th->min_sleep_time;
}
if (foreground)
wake_up_all(&gc_th->fggc_wq);
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:
if (sbi->gc_mode != GC_NORMAL) {
spin_lock(&sbi->gc_remaining_trials_lock);
if (sbi->gc_remaining_trials) {
sbi->gc_remaining_trials--;
if (!sbi->gc_remaining_trials)
sbi->gc_mode = GC_NORMAL;
}
spin_unlock(&sbi->gc_remaining_trials_lock);
}
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;
gc_th = f2fs_kmalloc(sbi, sizeof(struct f2fs_gc_kthread), GFP_KERNEL);
if (!gc_th)
return -ENOMEM;
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);
init_waitqueue_head(&sbi->gc_thread->fggc_wq);
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)) {
int err = PTR_ERR(gc_th->f2fs_gc_task);
kfree(gc_th);
sbi->gc_thread = NULL;
return err;
}
return 0;
}
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);
wake_up_all(&gc_th->fggc_wq);
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 (f2fs_need_rand_seg(sbi))
p->offset = prandom_u32() % (MAIN_SECS(sbi) * sbi->segs_per_sec);
else 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, true, NULL);
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 = CAP_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));
}
static bool f2fs_pin_section(struct f2fs_sb_info *sbi, unsigned int segno)
{
struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
unsigned int secno = GET_SEC_FROM_SEG(sbi, segno);
if (!dirty_i->enable_pin_section)
return false;
if (!test_and_set_bit(secno, dirty_i->pinned_secmap))
dirty_i->pinned_secmap_cnt++;
return true;
}
static bool f2fs_pinned_section_exists(struct dirty_seglist_info *dirty_i)
{
return dirty_i->pinned_secmap_cnt;
}
static bool f2fs_section_is_pinned(struct dirty_seglist_info *dirty_i,
unsigned int secno)
{
return dirty_i->enable_pin_section &&
f2fs_pinned_section_exists(dirty_i) &&
test_bit(secno, dirty_i->pinned_secmap);
}
static void f2fs_unpin_all_sections(struct f2fs_sb_info *sbi, bool enable)
{
unsigned int bitmap_size = f2fs_bitmap_size(MAIN_SECS(sbi));
if (f2fs_pinned_section_exists(DIRTY_I(sbi))) {
memset(DIRTY_I(sbi)->pinned_secmap, 0, bitmap_size);
DIRTY_I(sbi)->pinned_secmap_cnt = 0;
}
DIRTY_I(sbi)->enable_pin_section = enable;
}
static int f2fs_gc_pinned_control(struct inode *inode, int gc_type,
unsigned int segno)
{
if (!f2fs_is_pinned_file(inode))
return 0;
if (gc_type != FG_GC)
return -EBUSY;
if (!f2fs_pin_section(F2FS_I_SB(inode), segno))
f2fs_pin_file_control(inode, true);
return -EAGAIN;
}
/*
* 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 (gc_type == FG_GC && f2fs_section_is_pinned(dirty_i, secno))
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, true, NULL);
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, false)) {
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, false)) {
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",
blkaddr, source_blkaddr, segno);
set_sbi_flag(sbi, SBI_NEED_FSCK);
}
}
#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, };
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_read_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;
f2fs_handle_error(sbi, ERROR_INVALID_BLKADDR);
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;
f2fs_handle_error(sbi, ERROR_INVALID_BLKADDR);
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, inode, FS_DATA_READ_IO, F2FS_BLKSIZE);
f2fs_update_iostat(sbi, NULL, 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 && (gc_type == BG_GC) &&
(fio.sbi->gc_mode != GC_URGENT_HIGH) ?
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;
}
err = f2fs_gc_pinned_control(inode, gc_type, segno);
if (err)
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, false);
if (err)
goto put_out;
/* read page */
fio.page = page;
fio.new_blkaddr = fio.old_blkaddr = dn.data_blkaddr;
if (lfs_mode)
f2fs_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, inode, FS_DATA_READ_IO,
F2FS_BLKSIZE);
f2fs_update_iostat(fio.sbi, NULL, 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;
}
}
set_summary(&sum, dn.nid, dn.ofs_in_node, ni.version);
/* allocate block address */
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);
f2fs_invalidate_compress_page(fio.sbi, 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);
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, NULL, 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)
f2fs_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;
}
err = f2fs_gc_pinned_control(inode, gc_type, segno);
if (err)
goto out;
if (gc_type == BG_GC) {
if (PageWriteback(page)) {
err = -EAGAIN;
goto out;
}
set_page_dirty(page);
set_page_private_gcing(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_page_private_gcing(page);
err = f2fs_do_write_data_page(&fio);
if (err) {
clear_page_private_gcing(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) ==
CAP_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) {
int err;
inode = f2fs_iget(sb, dni.ino);
if (IS_ERR(inode) || is_bad_inode(inode) ||
special_file(inode->i_mode))
continue;
err = f2fs_gc_pinned_control(inode, gc_type, segno);
if (err == -EAGAIN) {
iput(inode);
return submitted;
}
if (!f2fs_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);
f2fs_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, NULL);
f2fs_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 (!f2fs_down_write_trylock(&fi->i_gc_rwsem[READ])) {
sbi->skipped_gc_rwsem++;
continue;
}
if (!f2fs_down_write_trylock(
&fi->i_gc_rwsem[WRITE])) {
sbi->skipped_gc_rwsem++;
f2fs_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) {
f2fs_up_write(&fi->i_gc_rwsem[WRITE]);
f2fs_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,
STOP_CP_REASON_CORRUPTED_SUMMARY);
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);
sbi->gc_reclaimed_segs[sbi->gc_mode]++;
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, struct f2fs_gc_control *gc_control)
{
int gc_type = gc_control->init_gc_type;
unsigned int segno = gc_control->victim_segno;
int sec_freed = 0, seg_freed = 0, total_freed = 0;
int ret = 0;
struct cp_control cpc;
struct gc_inode_list gc_list = {
.ilist = LIST_HEAD_INIT(gc_list.ilist),
.iroot = RADIX_TREE_INIT(gc_list.iroot, GFP_NOFS),
};
unsigned int skipped_round = 0, round = 0;
trace_f2fs_gc_begin(sbi->sb, gc_type, gc_control->no_bg_gc,
gc_control->nr_free_secs,
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;
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)) {
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 && gc_control->no_bg_gc) {
ret = -EINVAL;
goto stop;
}
retry:
ret = __get_victim(sbi, &segno, gc_type);
if (ret) {
/* allow to search victim from sections has pinned data */
if (ret == -ENODATA && gc_type == FG_GC &&
f2fs_pinned_section_exists(DIRTY_I(sbi))) {
f2fs_unpin_all_sections(sbi, false);
goto retry;
}
goto stop;
}
seg_freed = do_garbage_collect(sbi, segno, &gc_list, gc_type,
gc_control->should_migrate_blocks);
total_freed += seg_freed;
if (seg_freed == f2fs_usable_segs_in_sec(sbi, segno))
sec_freed++;
if (gc_type == FG_GC)
sbi->cur_victim_sec = NULL_SEGNO;
if (gc_control->init_gc_type == FG_GC ||
!has_not_enough_free_secs(sbi,
(gc_type == FG_GC) ? sec_freed : 0, 0)) {
if (gc_type == FG_GC && sec_freed < gc_control->nr_free_secs)
goto go_gc_more;
goto stop;
}
/* FG_GC stops GC by skip_count */
if (gc_type == FG_GC) {
if (sbi->skipped_gc_rwsem)
skipped_round++;
round++;
if (skipped_round > MAX_SKIP_GC_COUNT &&
skipped_round * 2 >= round) {
ret = f2fs_write_checkpoint(sbi, &cpc);
goto stop;
}
}
/* Write checkpoint to reclaim prefree segments */
if (free_sections(sbi) < NR_CURSEG_PERSIST_TYPE &&
prefree_segments(sbi)) {
ret = f2fs_write_checkpoint(sbi, &cpc);
if (ret)
goto stop;
}
go_gc_more:
segno = NULL_SEGNO;
goto gc_more;
stop:
SIT_I(sbi)->last_victim[ALLOC_NEXT] = 0;
SIT_I(sbi)->last_victim[FLUSH_DEVICE] = gc_control->victim_segno;
if (gc_type == FG_GC)
f2fs_unpin_all_sections(sbi, true);
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));
f2fs_up_write(&sbi->gc_lock);
put_gc_inode(&gc_list);
if (gc_control->err_gc_skipped && !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));
return victim_entry_slab ? 0 : -ENOMEM;
}
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;
f2fs_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);
}
f2fs_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 f2fs_sb_info *sbi, __u64 block_count)
{
__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;
}
shrunk_blocks = old_block_count - block_count;
secs = div_u64(shrunk_blocks, BLKS_PER_SEC(sbi));
/* stop other GC */
if (!f2fs_down_write_trylock(&sbi->gc_lock))
return -EAGAIN;
/* 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);
f2fs_up_write(&sbi->gc_lock);
if (err)
return err;
freeze_super(sbi->sb);
f2fs_down_write(&sbi->gc_lock);
f2fs_down_write(&sbi->cp_global_sem);
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:
f2fs_up_write(&sbi->cp_global_sem);
f2fs_up_write(&sbi->gc_lock);
thaw_super(sbi->sb);
return err;
}