Re: [PATCH 3/4] f2fs: fix to handle segment allocation failure correctly

Zhiguo Niu
2024-02-26T10:28:23Z

On Mon, Feb 26, 2024 at 3:46 PM Chao Yu <chao@kernel.org> wrote:
>
> Loop to Zhiguo,
>
> On 2024/2/22 20:18, Chao Yu wrote:
> > If CONFIG_F2FS_CHECK_FS is off, and for very rare corner case that
> > we run out of free segment, we should not panic kernel, instead,
> > let's handle such error correctly in its caller.
> >
> > Signed-off-by: Chao Yu <chao@kernel.org>
Tested-by: Zhiguo Niu <zhiguo.niu@unisoc.com>
Thanks!
> > ---
> > fs/f2fs/data.c | 7 +++++--
> > fs/f2fs/f2fs.h | 2 +-
> > fs/f2fs/file.c | 7 ++++++-
> > fs/f2fs/gc.c | 7 ++++++-
> > fs/f2fs/segment.c | 46 +++++++++++++++++++++++++++++++++++++++-------
> > 5 files changed, 57 insertions(+), 12 deletions(-)
> >
> > diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
> > index 0c9aa3082fcf..c21b92f18463 100644
> > --- a/fs/f2fs/data.c
> > +++ b/fs/f2fs/data.c
> > @@ -1416,8 +1416,11 @@ static int __allocate_data_block(struct dnode_of_data *dn, int seg_type)
> >
> > set_summary(&sum, dn->nid, dn->ofs_in_node, ni.version);
> > old_blkaddr = dn->data_blkaddr;
> > - f2fs_allocate_data_block(sbi, NULL, old_blkaddr, &dn->data_blkaddr,
> > - &sum, seg_type, NULL);
> > + err = f2fs_allocate_data_block(sbi, NULL, old_blkaddr,
> > + &dn->data_blkaddr, &sum, seg_type, NULL);
> > + if (err)
> > + return err;
> > +
> > if (GET_SEGNO(sbi, old_blkaddr) != NULL_SEGNO)
> > f2fs_invalidate_internal_cache(sbi, old_blkaddr);
> >
> > diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
> > index fbbe9a0a4221..6390c3d551cb 100644
> > --- a/fs/f2fs/f2fs.h
> > +++ b/fs/f2fs/f2fs.h
> > @@ -3726,7 +3726,7 @@ void f2fs_replace_block(struct f2fs_sb_info *sbi, struct dnode_of_data *dn,
> > block_t old_addr, block_t new_addr,
> > unsigned char version, bool recover_curseg,
> > bool recover_newaddr);
> > -void f2fs_allocate_data_block(struct f2fs_sb_info *sbi, struct page *page,
> > +int f2fs_allocate_data_block(struct f2fs_sb_info *sbi, struct page *page,
> > block_t old_blkaddr, block_t *new_blkaddr,
> > struct f2fs_summary *sum, int type,
> > struct f2fs_io_info *fio);
> > diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
> > index 088d0e79fbbc..d6ec744f1545 100644
> > --- a/fs/f2fs/file.c
> > +++ b/fs/f2fs/file.c
> > @@ -2262,8 +2262,11 @@ static int f2fs_ioc_shutdown(struct file *filp, unsigned long arg)
> > case F2FS_GOING_DOWN_METASYNC:
> > /* do checkpoint only */
> > ret = f2fs_sync_fs(sb, 1);
> > - if (ret)
> > + if (ret) {
> > + if (ret == -EIO)
> > + ret = 0;
> > goto out;
> > + }
> > f2fs_stop_checkpoint(sbi, false, STOP_CP_REASON_SHUTDOWN);
> > break;
> > case F2FS_GOING_DOWN_NOSYNC:
> > @@ -2279,6 +2282,8 @@ static int f2fs_ioc_shutdown(struct file *filp, unsigned long arg)
> > set_sbi_flag(sbi, SBI_IS_DIRTY);
> > /* do checkpoint only */
> > ret = f2fs_sync_fs(sb, 1);
> > + if (ret == -EIO)
> > + ret = 0;
> > goto out;
> > default:
> > ret = -EINVAL;
> > diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
> > index 6d160d50e14e..42e75e9b8b6b 100644
> > --- a/fs/f2fs/gc.c
> > +++ b/fs/f2fs/gc.c
> > @@ -1358,8 +1358,13 @@ static int move_data_block(struct inode *inode, block_t bidx,
> > 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,
> > + err = f2fs_allocate_data_block(fio.sbi, NULL, fio.old_blkaddr, &newaddr,
> > &sum, type, NULL);
> > + if (err) {
> > + f2fs_put_page(mpage, 1);
> > + /* filesystem should shutdown, no need to recovery block */
> > + goto up_out;
> > + }
> >
> > fio.encrypted_page = f2fs_pagecache_get_page(META_MAPPING(fio.sbi),
> > newaddr, FGP_LOCK | FGP_CREAT, GFP_NOFS);
> > diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
> > index 8edc42071e6f..71f523431e87 100644
> > --- a/fs/f2fs/segment.c
> > +++ b/fs/f2fs/segment.c
> > @@ -400,6 +400,9 @@ int f2fs_commit_atomic_write(struct inode *inode)
> > */
> > void f2fs_balance_fs(struct f2fs_sb_info *sbi, bool need)
> > {
> > + if (f2fs_cp_error(sbi))
> > + return;
> > +
> > if (time_to_inject(sbi, FAULT_CHECKPOINT))
> > f2fs_stop_checkpoint(sbi, false, STOP_CP_REASON_FAULT_INJECT);
> >
> > @@ -2636,7 +2639,7 @@ static int is_next_segment_free(struct f2fs_sb_info *sbi,
> > * Find a new segment from the free segments bitmap to right order
> > * This function should be returned with success, otherwise BUG
> > */
> > -static void get_new_segment(struct f2fs_sb_info *sbi,
> > +static int get_new_segment(struct f2fs_sb_info *sbi,
> > unsigned int *newseg, bool new_sec, bool pinning)
> > {
> > struct free_segmap_info *free_i = FREE_I(sbi);
> > @@ -2711,6 +2714,7 @@ static void get_new_segment(struct f2fs_sb_info *sbi,
> > f2fs_stop_checkpoint(sbi, false, STOP_CP_REASON_NO_SEGMENT);
> > f2fs_bug_on(sbi, 1);
> > }
> > + return ret;
> > }
> >
> > static void reset_curseg(struct f2fs_sb_info *sbi, int type, int modified)
> > @@ -2719,6 +2723,10 @@ static void reset_curseg(struct f2fs_sb_info *sbi, int type, int modified)
> > struct summary_footer *sum_footer;
> > unsigned short seg_type = curseg->seg_type;
> >
> > + /* only happen when get_new_segment() fails */
> > + if (curseg->next_segno == NULL_SEGNO)
> > + return;
> > +
> > curseg->inited = true;
> > curseg->segno = curseg->next_segno;
> > curseg->zone = GET_ZONE_FROM_SEG(sbi, curseg->segno);
> > @@ -2783,7 +2791,10 @@ static int new_curseg(struct f2fs_sb_info *sbi, int type, bool new_sec)
> > write_sum_page(sbi, curseg->sum_blk, GET_SUM_BLOCK(sbi, segno));
> >
> > segno = __get_next_segno(sbi, type);
> > - get_new_segment(sbi, &segno, new_sec, pinning);
> > + if (get_new_segment(sbi, &segno, new_sec, pinning)) {
> > + curseg->segno = NULL_SEGNO;
> > + return -ENOSPC;
> > + }
> > if (new_sec && pinning &&
> > !f2fs_valid_pinned_area(sbi, START_BLOCK(sbi, segno))) {
> > __set_free(sbi, segno);
> > @@ -3425,7 +3436,7 @@ static void f2fs_randomize_chunk(struct f2fs_sb_info *sbi,
> > get_random_u32_inclusive(1, sbi->max_fragment_hole);
> > }
> >
> > -void f2fs_allocate_data_block(struct f2fs_sb_info *sbi, struct page *page,
> > +int f2fs_allocate_data_block(struct f2fs_sb_info *sbi, struct page *page,
> > block_t old_blkaddr, block_t *new_blkaddr,
> > struct f2fs_summary *sum, int type,
> > struct f2fs_io_info *fio)
> > @@ -3442,6 +3453,9 @@ void f2fs_allocate_data_block(struct f2fs_sb_info *sbi, struct page *page,
> > mutex_lock(&curseg->curseg_mutex);
> > down_write(&sit_i->sentry_lock);
> >
> > + if (curseg->segno == NULL_SEGNO)
> > + goto out_err;
> > +
> > if (from_gc) {
> > f2fs_bug_on(sbi, GET_SEGNO(sbi, old_blkaddr) == NULL_SEGNO);
> > se = get_seg_entry(sbi, GET_SEGNO(sbi, old_blkaddr));
> > @@ -3500,6 +3514,9 @@ void f2fs_allocate_data_block(struct f2fs_sb_info *sbi, struct page *page,
> > change_curseg(sbi, type);
> > stat_inc_seg_type(sbi, curseg);
> > }
> > +
> > + if (curseg->segno == NULL_SEGNO)
> > + goto out_err;
> > }
> >
> > skip_new_segment:
> > @@ -3534,8 +3551,15 @@ void f2fs_allocate_data_block(struct f2fs_sb_info *sbi, struct page *page,
> > }
> >
> > mutex_unlock(&curseg->curseg_mutex);
> > -
> > f2fs_up_read(&SM_I(sbi)->curseg_lock);
> > + return 0;
> > +out_err:
> > + *new_blkaddr = NULL_ADDR;
> > + up_write(&sit_i->sentry_lock);
> > + mutex_unlock(&curseg->curseg_mutex);
> > + f2fs_up_read(&SM_I(sbi)->curseg_lock);
> > + return -ENOSPC;
> > +
> > }
> >
> > void f2fs_update_device_state(struct f2fs_sb_info *sbi, nid_t ino,
> > @@ -3573,8 +3597,16 @@ static void do_write_page(struct f2fs_summary *sum, struct f2fs_io_info *fio)
> > if (keep_order)
> > f2fs_down_read(&fio->sbi->io_order_lock);
> >
> > - f2fs_allocate_data_block(fio->sbi, fio->page, fio->old_blkaddr,
> > - &fio->new_blkaddr, sum, type, fio);
> > + if (f2fs_allocate_data_block(fio->sbi, fio->page, fio->old_blkaddr,
> > + &fio->new_blkaddr, sum, type, fio)) {
> > + if (fscrypt_inode_uses_fs_layer_crypto(fio->page->mapping->host))
> > + fscrypt_finalize_bounce_page(&fio->encrypted_page);
> > + if (PageWriteback(fio->page))
> > + end_page_writeback(fio->page);
> > + if (f2fs_in_warm_node_list(fio->sbi, fio->page))
> > + f2fs_del_fsync_node_entry(fio->sbi, fio->page);
> > + goto out;
> > + }
> > if (GET_SEGNO(fio->sbi, fio->old_blkaddr) != NULL_SEGNO)
> > f2fs_invalidate_internal_cache(fio->sbi, fio->old_blkaddr);
> >
> > @@ -3582,7 +3614,7 @@ static void do_write_page(struct f2fs_summary *sum, struct f2fs_io_info *fio)
> > f2fs_submit_page_write(fio);
> >
> > f2fs_update_device_state(fio->sbi, fio->ino, fio->new_blkaddr, 1);
> > -
> > +out:
> > if (keep_order)
> > f2fs_up_read(&fio->sbi->io_order_lock);
> > }