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-rw-r--r--fs/f2fs/gc.c746
1 files changed, 746 insertions, 0 deletions
diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
new file mode 100644
index 000000000..ed58211fe
--- /dev/null
+++ b/fs/f2fs/gc.c
@@ -0,0 +1,746 @@
+/*
+ * fs/f2fs/gc.c
+ *
+ * Copyright (c) 2012 Samsung Electronics Co., Ltd.
+ * http://www.samsung.com/
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#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/blkdev.h>
+
+#include "f2fs.h"
+#include "node.h"
+#include "segment.h"
+#include "gc.h"
+#include <trace/events/f2fs.h>
+
+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;
+ long wait_ms;
+
+ wait_ms = gc_th->min_sleep_time;
+
+ do {
+ if (try_to_freeze())
+ continue;
+ else
+ wait_event_interruptible_timeout(*wq,
+ kthread_should_stop(),
+ msecs_to_jiffies(wait_ms));
+ if (kthread_should_stop())
+ break;
+
+ if (sbi->sb->s_writers.frozen >= SB_FREEZE_WRITE) {
+ increase_sleep_time(gc_th, &wait_ms);
+ 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 (!mutex_trylock(&sbi->gc_mutex))
+ continue;
+
+ if (!is_idle(sbi)) {
+ increase_sleep_time(gc_th, &wait_ms);
+ mutex_unlock(&sbi->gc_mutex);
+ continue;
+ }
+
+ if (has_enough_invalid_blocks(sbi))
+ decrease_sleep_time(gc_th, &wait_ms);
+ else
+ increase_sleep_time(gc_th, &wait_ms);
+
+ stat_inc_bggc_count(sbi);
+
+ /* if return value is not zero, no victim was selected */
+ if (f2fs_gc(sbi))
+ wait_ms = gc_th->no_gc_sleep_time;
+
+ /* balancing f2fs's metadata periodically */
+ f2fs_balance_fs_bg(sbi);
+
+ } while (!kthread_should_stop());
+ return 0;
+}
+
+int 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 = kmalloc(sizeof(struct f2fs_gc_kthread), GFP_KERNEL);
+ if (!gc_th) {
+ err = -ENOMEM;
+ goto out;
+ }
+
+ 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_idle = 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 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_gc_kthread *gc_th, int gc_type)
+{
+ int gc_mode = (gc_type == BG_GC) ? GC_CB : GC_GREEDY;
+
+ if (gc_th && gc_th->gc_idle) {
+ if (gc_th->gc_idle == 1)
+ gc_mode = GC_CB;
+ else if (gc_th->gc_idle == 2)
+ gc_mode = GC_GREEDY;
+ }
+ 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_segmap = 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_thread, gc_type);
+ p->dirty_segmap = dirty_i->dirty_segmap[DIRTY];
+ p->max_search = dirty_i->nr_dirty[DIRTY];
+ p->ofs_unit = sbi->segs_per_sec;
+ }
+
+ if (p->max_search > sbi->max_victim_search)
+ p->max_search = sbi->max_victim_search;
+
+ p->offset = 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 1 << sbi->log_blocks_per_seg;
+ if (p->gc_mode == GC_GREEDY)
+ return (1 << sbi->log_blocks_per_seg) * p->ofs_unit;
+ else if (p->gc_mode == GC_CB)
+ 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 secno * sbi->segs_per_sec;
+ }
+ 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_SECNO(sbi, segno);
+ unsigned int start = secno * sbi->segs_per_sec;
+ unsigned long long mtime = 0;
+ unsigned int vblocks;
+ unsigned char age = 0;
+ unsigned char u;
+ unsigned int i;
+
+ for (i = 0; i < sbi->segs_per_sec; i++)
+ mtime += get_seg_entry(sbi, start + i)->mtime;
+ vblocks = get_valid_blocks(sbi, segno, sbi->segs_per_sec);
+
+ mtime = div_u64(mtime, sbi->segs_per_sec);
+ vblocks = div_u64(vblocks, sbi->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, sbi->segs_per_sec);
+ else
+ return get_cb_cost(sbi, segno);
+}
+
+/*
+ * 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)
+{
+ struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
+ struct victim_sel_policy p;
+ unsigned int secno, max_cost;
+ int nsearched = 0;
+
+ mutex_lock(&dirty_i->seglist_lock);
+
+ p.alloc_mode = alloc_mode;
+ select_policy(sbi, gc_type, type, &p);
+
+ p.min_segno = NULL_SEGNO;
+ p.min_cost = max_cost = get_max_cost(sbi, &p);
+
+ 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;
+ unsigned int segno;
+
+ segno = find_next_bit(p.dirty_segmap, MAIN_SEGS(sbi), p.offset);
+ if (segno >= MAIN_SEGS(sbi)) {
+ if (sbi->last_victim[p.gc_mode]) {
+ sbi->last_victim[p.gc_mode] = 0;
+ p.offset = 0;
+ continue;
+ }
+ break;
+ }
+
+ p.offset = segno + p.ofs_unit;
+ if (p.ofs_unit > 1)
+ p.offset -= segno % p.ofs_unit;
+
+ secno = GET_SECNO(sbi, segno);
+
+ if (sec_usage_check(sbi, secno))
+ continue;
+ if (gc_type == BG_GC && test_bit(secno, dirty_i->victim_secmap))
+ continue;
+
+ cost = get_gc_cost(sbi, segno, &p);
+
+ if (p.min_cost > cost) {
+ p.min_segno = segno;
+ p.min_cost = cost;
+ } else if (unlikely(cost == max_cost)) {
+ continue;
+ }
+
+ if (nsearched++ >= p.max_search) {
+ sbi->last_victim[p.gc_mode] = segno;
+ break;
+ }
+ }
+ if (p.min_segno != NULL_SEGNO) {
+got_it:
+ if (p.alloc_mode == LFS) {
+ secno = GET_SECNO(sbi, p.min_segno);
+ if (gc_type == FG_GC)
+ sbi->cur_victim_sec = secno;
+ else
+ set_bit(secno, dirty_i->victim_secmap);
+ }
+ *result = (p.min_segno / p.ofs_unit) * p.ofs_unit;
+
+ 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 (p.min_segno == NULL_SEGNO) ? 0 : 1;
+}
+
+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(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(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;
+
+ mutex_lock(&sit_i->sentry_lock);
+ sentry = get_seg_entry(sbi, segno);
+ ret = f2fs_test_bit(offset, sentry->cur_valid_map);
+ mutex_unlock(&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 void gc_node_segment(struct f2fs_sb_info *sbi,
+ struct f2fs_summary *sum, unsigned int segno, int gc_type)
+{
+ bool initial = true;
+ struct f2fs_summary *entry;
+ int off;
+
+next_step:
+ entry = sum;
+
+ for (off = 0; off < sbi->blocks_per_seg; off++, entry++) {
+ nid_t nid = le32_to_cpu(entry->nid);
+ struct page *node_page;
+
+ /* stop BG_GC if there is not enough free sections. */
+ if (gc_type == BG_GC && has_not_enough_free_secs(sbi, 0))
+ return;
+
+ if (check_valid_map(sbi, segno, off) == 0)
+ continue;
+
+ if (initial) {
+ ra_node_page(sbi, nid);
+ continue;
+ }
+ node_page = get_node_page(sbi, nid);
+ if (IS_ERR(node_page))
+ continue;
+
+ /* block may become invalid during get_node_page */
+ if (check_valid_map(sbi, segno, off) == 0) {
+ f2fs_put_page(node_page, 1);
+ continue;
+ }
+
+ /* set page dirty and write it */
+ if (gc_type == FG_GC) {
+ f2fs_wait_on_page_writeback(node_page, NODE);
+ set_page_dirty(node_page);
+ } else {
+ if (!PageWriteback(node_page))
+ set_page_dirty(node_page);
+ }
+ f2fs_put_page(node_page, 1);
+ stat_inc_node_blk_count(sbi, 1, gc_type);
+ }
+
+ if (initial) {
+ initial = false;
+ goto next_step;
+ }
+
+ if (gc_type == FG_GC) {
+ struct writeback_control wbc = {
+ .sync_mode = WB_SYNC_ALL,
+ .nr_to_write = LONG_MAX,
+ .for_reclaim = 0,
+ };
+ sync_node_pages(sbi, 0, &wbc);
+
+ /*
+ * In the case of FG_GC, it'd be better to reclaim this victim
+ * completely.
+ */
+ if (get_valid_blocks(sbi, segno, 1) != 0)
+ goto next_step;
+ }
+}
+
+/*
+ * 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 start_bidx_of_node(unsigned int node_ofs, struct f2fs_inode_info *fi)
+{
+ 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 + ADDRS_PER_INODE(fi);
+}
+
+static int check_dnode(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;
+ block_t source_blkaddr;
+
+ nid = le32_to_cpu(sum->nid);
+ ofs_in_node = le16_to_cpu(sum->ofs_in_node);
+
+ node_page = get_node_page(sbi, nid);
+ if (IS_ERR(node_page))
+ return 0;
+
+ get_node_info(sbi, nid, dni);
+
+ if (sum->version != dni->version) {
+ f2fs_put_page(node_page, 1);
+ return 0;
+ }
+
+ *nofs = ofs_of_node(node_page);
+ source_blkaddr = datablock_addr(node_page, ofs_in_node);
+ f2fs_put_page(node_page, 1);
+
+ if (source_blkaddr != blkaddr)
+ return 0;
+ return 1;
+}
+
+static void move_data_page(struct inode *inode, struct page *page, int gc_type)
+{
+ struct f2fs_io_info fio = {
+ .type = DATA,
+ .rw = WRITE_SYNC,
+ };
+
+ if (gc_type == BG_GC) {
+ if (PageWriteback(page))
+ goto out;
+ set_page_dirty(page);
+ set_cold_data(page);
+ } else {
+ f2fs_wait_on_page_writeback(page, DATA);
+
+ if (clear_page_dirty_for_io(page))
+ inode_dec_dirty_pages(inode);
+ set_cold_data(page);
+ do_write_data_page(page, &fio);
+ clear_cold_data(page);
+ }
+out:
+ f2fs_put_page(page, 1);
+}
+
+/*
+ * 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 void gc_data_segment(struct f2fs_sb_info *sbi, struct f2fs_summary *sum,
+ struct gc_inode_list *gc_list, unsigned int segno, int gc_type)
+{
+ struct super_block *sb = sbi->sb;
+ struct f2fs_summary *entry;
+ block_t start_addr;
+ int off;
+ int phase = 0;
+
+ start_addr = START_BLOCK(sbi, segno);
+
+next_step:
+ entry = sum;
+
+ for (off = 0; off < sbi->blocks_per_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;
+
+ /* stop BG_GC if there is not enough free sections. */
+ if (gc_type == BG_GC && has_not_enough_free_secs(sbi, 0))
+ return;
+
+ if (check_valid_map(sbi, segno, off) == 0)
+ continue;
+
+ if (phase == 0) {
+ ra_node_page(sbi, le32_to_cpu(entry->nid));
+ continue;
+ }
+
+ /* Get an inode by ino with checking validity */
+ if (check_dnode(sbi, entry, &dni, start_addr + off, &nofs) == 0)
+ continue;
+
+ if (phase == 1) {
+ ra_node_page(sbi, dni.ino);
+ continue;
+ }
+
+ ofs_in_node = le16_to_cpu(entry->ofs_in_node);
+
+ if (phase == 2) {
+ inode = f2fs_iget(sb, dni.ino);
+ if (IS_ERR(inode) || is_bad_inode(inode))
+ continue;
+
+ start_bidx = start_bidx_of_node(nofs, F2FS_I(inode));
+
+ data_page = find_data_page(inode,
+ start_bidx + ofs_in_node, false);
+ if (IS_ERR(data_page)) {
+ iput(inode);
+ continue;
+ }
+
+ f2fs_put_page(data_page, 0);
+ add_gc_inode(gc_list, inode);
+ continue;
+ }
+
+ /* phase 3 */
+ inode = find_gc_inode(gc_list, dni.ino);
+ if (inode) {
+ start_bidx = start_bidx_of_node(nofs, F2FS_I(inode));
+ data_page = get_lock_data_page(inode,
+ start_bidx + ofs_in_node);
+ if (IS_ERR(data_page))
+ continue;
+ move_data_page(inode, data_page, gc_type);
+ stat_inc_data_blk_count(sbi, 1, gc_type);
+ }
+ }
+
+ if (++phase < 4)
+ goto next_step;
+
+ if (gc_type == FG_GC) {
+ f2fs_submit_merged_bio(sbi, DATA, WRITE);
+
+ /*
+ * In the case of FG_GC, it'd be better to reclaim this victim
+ * completely.
+ */
+ if (get_valid_blocks(sbi, segno, 1) != 0) {
+ phase = 2;
+ goto next_step;
+ }
+ }
+}
+
+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;
+
+ mutex_lock(&sit_i->sentry_lock);
+ ret = DIRTY_I(sbi)->v_ops->get_victim(sbi, victim, gc_type,
+ NO_CHECK_TYPE, LFS);
+ mutex_unlock(&sit_i->sentry_lock);
+ return ret;
+}
+
+static void do_garbage_collect(struct f2fs_sb_info *sbi, unsigned int segno,
+ struct gc_inode_list *gc_list, int gc_type)
+{
+ struct page *sum_page;
+ struct f2fs_summary_block *sum;
+ struct blk_plug plug;
+
+ /* read segment summary of victim */
+ sum_page = get_sum_page(sbi, segno);
+
+ blk_start_plug(&plug);
+
+ sum = page_address(sum_page);
+
+ switch (GET_SUM_TYPE((&sum->footer))) {
+ case SUM_TYPE_NODE:
+ gc_node_segment(sbi, sum->entries, segno, gc_type);
+ break;
+ case SUM_TYPE_DATA:
+ gc_data_segment(sbi, sum->entries, gc_list, segno, gc_type);
+ break;
+ }
+ blk_finish_plug(&plug);
+
+ stat_inc_seg_count(sbi, GET_SUM_TYPE((&sum->footer)), gc_type);
+ stat_inc_call_count(sbi->stat_info);
+
+ f2fs_put_page(sum_page, 1);
+}
+
+int f2fs_gc(struct f2fs_sb_info *sbi)
+{
+ unsigned int segno, i;
+ int gc_type = BG_GC;
+ int nfree = 0;
+ int ret = -1;
+ struct cp_control cpc;
+ struct gc_inode_list gc_list = {
+ .ilist = LIST_HEAD_INIT(gc_list.ilist),
+ .iroot = RADIX_TREE_INIT(GFP_NOFS),
+ };
+
+ cpc.reason = __get_cp_reason(sbi);
+gc_more:
+ if (unlikely(!(sbi->sb->s_flags & MS_ACTIVE)))
+ goto stop;
+ if (unlikely(f2fs_cp_error(sbi)))
+ goto stop;
+
+ if (gc_type == BG_GC && has_not_enough_free_secs(sbi, nfree)) {
+ gc_type = FG_GC;
+ write_checkpoint(sbi, &cpc);
+ }
+
+ if (!__get_victim(sbi, &segno, gc_type))
+ goto stop;
+ ret = 0;
+
+ /* readahead multi ssa blocks those have contiguous address */
+ if (sbi->segs_per_sec > 1)
+ ra_meta_pages(sbi, GET_SUM_BLOCK(sbi, segno), sbi->segs_per_sec,
+ META_SSA);
+
+ for (i = 0; i < sbi->segs_per_sec; i++)
+ do_garbage_collect(sbi, segno + i, &gc_list, gc_type);
+
+ if (gc_type == FG_GC) {
+ sbi->cur_victim_sec = NULL_SEGNO;
+ nfree++;
+ WARN_ON(get_valid_blocks(sbi, segno, sbi->segs_per_sec));
+ }
+
+ if (has_not_enough_free_secs(sbi, nfree))
+ goto gc_more;
+
+ if (gc_type == FG_GC)
+ write_checkpoint(sbi, &cpc);
+stop:
+ mutex_unlock(&sbi->gc_mutex);
+
+ put_gc_inode(&gc_list);
+ return ret;
+}
+
+void build_gc_manager(struct f2fs_sb_info *sbi)
+{
+ DIRTY_I(sbi)->v_ops = &default_v_ops;
+}