From 6a8f8ca582a1bafe6b620e000316206c8719f1d0 Mon Sep 17 00:00:00 2001 From: Jaegeuk Kim Date: Wed, 29 Oct 2014 14:37:22 -0700 Subject: [PATCH] f2fs: avoid race condition in handling wait_io __submit_merged_bio f2fs_write_end_io f2fs_write_end_io wait_io = X wait_io = x complete(X) complete(X) wait_io = NULL wait_for_completion() free(X) spin_lock(X) kernel panic In order to avoid this, this patch removes the wait_io facility. Instead, we can use wait_on_all_pages_writeback(sbi) to wait for end_ios. Signed-off-by: Jaegeuk Kim --- fs/f2fs/checkpoint.c | 3 +++ fs/f2fs/data.c | 35 +++++++---------------------------- fs/f2fs/f2fs.h | 1 - 3 files changed, 10 insertions(+), 29 deletions(-) diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c index ca514d599b79..dd6a357a59de 100644 --- a/fs/f2fs/checkpoint.c +++ b/fs/f2fs/checkpoint.c @@ -978,6 +978,9 @@ static void do_checkpoint(struct f2fs_sb_info *sbi, struct cp_control *cpc) /* Here, we only have one bio having CP pack */ sync_meta_pages(sbi, META_FLUSH, LONG_MAX); + /* wait for previous submitted meta pages writeback */ + wait_on_all_pages_writeback(sbi); + release_dirty_inode(sbi); if (unlikely(f2fs_cp_error(sbi))) diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c index ceee1a69c5aa..8f164432408e 100644 --- a/fs/f2fs/data.c +++ b/fs/f2fs/data.c @@ -61,11 +61,6 @@ static void f2fs_write_end_io(struct bio *bio, int err) dec_page_count(sbi, F2FS_WRITEBACK); } - if (sbi->wait_io) { - complete(sbi->wait_io); - sbi->wait_io = NULL; - } - if (!get_pages(sbi, F2FS_WRITEBACK) && !list_empty(&sbi->cp_wait.task_list)) wake_up(&sbi->cp_wait); @@ -95,34 +90,18 @@ static struct bio *__bio_alloc(struct f2fs_sb_info *sbi, block_t blk_addr, static void __submit_merged_bio(struct f2fs_bio_info *io) { struct f2fs_io_info *fio = &io->fio; - int rw; if (!io->bio) return; - rw = fio->rw; - - if (is_read_io(rw)) { - trace_f2fs_submit_read_bio(io->sbi->sb, rw, - fio->type, io->bio); - submit_bio(rw, io->bio); - } else { - trace_f2fs_submit_write_bio(io->sbi->sb, rw, - fio->type, io->bio); - /* - * META_FLUSH is only from the checkpoint procedure, and we - * should wait this metadata bio for FS consistency. - */ - if (fio->type == META_FLUSH) { - DECLARE_COMPLETION_ONSTACK(wait); - io->sbi->wait_io = &wait; - submit_bio(rw, io->bio); - wait_for_completion(&wait); - } else { - submit_bio(rw, io->bio); - } - } + if (is_read_io(fio->rw)) + trace_f2fs_submit_read_bio(io->sbi->sb, fio->rw, + fio->type, io->bio); + else + trace_f2fs_submit_write_bio(io->sbi->sb, fio->rw, + fio->type, io->bio); + submit_bio(fio->rw, io->bio); io->bio = NULL; } diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h index afe3022ffac5..5a9705842f10 100644 --- a/fs/f2fs/f2fs.h +++ b/fs/f2fs/f2fs.h @@ -516,7 +516,6 @@ struct f2fs_sb_info { /* for bio operations */ struct f2fs_bio_info read_io; /* for read bios */ struct f2fs_bio_info write_io[NR_PAGE_TYPE]; /* for write bios */ - struct completion *wait_io; /* for completion bios */ /* for checkpoint */ struct f2fs_checkpoint *ckpt; /* raw checkpoint pointer */ -- 2.34.1