From 740432f835608d11b5386321ab5aa8f61e07fb27 Mon Sep 17 00:00:00 2001 From: Jaegeuk Kim Date: Fri, 14 Aug 2015 11:43:56 -0700 Subject: [PATCH] f2fs: handle failed bio allocation As the below comment of bio_alloc_bioset, f2fs can allocate multiple bios at the same time. So, we can't guarantee that bio is allocated all the time. " * When @bs is not NULL, if %__GFP_WAIT is set then bio_alloc will always be * able to allocate a bio. This is due to the mempool guarantees. To make this * work, callers must never allocate more than 1 bio at a time from this pool. * Callers that need to allocate more than 1 bio must always submit the * previously allocated bio for IO before attempting to allocate a new one. * Failure to do so can cause deadlocks under memory pressure. " Signed-off-by: Jaegeuk Kim --- fs/f2fs/data.c | 3 +-- fs/f2fs/f2fs.h | 15 +++++++++++++++ fs/f2fs/segment.c | 15 ++++++++++++--- 3 files changed, 28 insertions(+), 5 deletions(-) diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c index cad9ebe45692..726e58b76295 100644 --- a/fs/f2fs/data.c +++ b/fs/f2fs/data.c @@ -90,8 +90,7 @@ static struct bio *__bio_alloc(struct f2fs_sb_info *sbi, block_t blk_addr, { struct bio *bio; - /* No failure on bio allocation */ - bio = bio_alloc(GFP_NOIO, npages); + bio = f2fs_bio_alloc(npages); bio->bi_bdev = sbi->sb->s_bdev; bio->bi_iter.bi_sector = SECTOR_FROM_BLOCK(blk_addr); diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h index 830848836da5..00591f725744 100644 --- a/fs/f2fs/f2fs.h +++ b/fs/f2fs/f2fs.h @@ -19,6 +19,7 @@ #include #include #include +#include #ifdef CONFIG_F2FS_CHECK_FS #define f2fs_bug_on(sbi, condition) BUG_ON(condition) @@ -1253,6 +1254,20 @@ retry: return entry; } +static inline struct bio *f2fs_bio_alloc(int npages) +{ + struct bio *bio; + + /* No failure on bio allocation */ +retry: + bio = bio_alloc(GFP_NOIO, npages); + if (!bio) { + cond_resched(); + goto retry; + } + return bio; +} + static inline void f2fs_radix_tree_insert(struct radix_tree_root *root, unsigned long index, void *item) { diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c index 1b4265639f07..6273e2cde93e 100644 --- a/fs/f2fs/segment.c +++ b/fs/f2fs/segment.c @@ -330,10 +330,12 @@ repeat: return 0; if (!llist_empty(&fcc->issue_list)) { - struct bio *bio = bio_alloc(GFP_NOIO, 0); + struct bio *bio; struct flush_cmd *cmd, *next; int ret; + bio = f2fs_bio_alloc(0); + fcc->dispatch_list = llist_del_all(&fcc->issue_list); fcc->dispatch_list = llist_reverse_order(fcc->dispatch_list); @@ -365,8 +367,15 @@ int f2fs_issue_flush(struct f2fs_sb_info *sbi) if (test_opt(sbi, NOBARRIER)) return 0; - if (!test_opt(sbi, FLUSH_MERGE)) - return blkdev_issue_flush(sbi->sb->s_bdev, GFP_KERNEL, NULL); + if (!test_opt(sbi, FLUSH_MERGE)) { + struct bio *bio = f2fs_bio_alloc(0); + int ret; + + bio->bi_bdev = sbi->sb->s_bdev; + ret = submit_bio_wait(WRITE_FLUSH, bio); + bio_put(bio); + return ret; + } init_completion(&cmd.wait); -- 2.34.1