6.6-stable review patch. If anyone has any objections, please let me know.
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From: Chao Yu chao@kernel.org
[ Upstream commit 1005a3ca28e90c7a64fa43023f866b960a60f791 ]
w/ "mode=lfs" mount option, generic/299 will cause system panic as below:
------------[ cut here ]------------ kernel BUG at fs/f2fs/segment.c:2835! Call Trace: <TASK> f2fs_allocate_data_block+0x6f4/0xc50 f2fs_map_blocks+0x970/0x1550 f2fs_iomap_begin+0xb2/0x1e0 iomap_iter+0x1d6/0x430 __iomap_dio_rw+0x208/0x9a0 f2fs_file_write_iter+0x6b3/0xfa0 aio_write+0x15d/0x2e0 io_submit_one+0x55e/0xab0 __x64_sys_io_submit+0xa5/0x230 do_syscall_64+0x84/0x2f0 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0010:new_curseg+0x70f/0x720
The root cause of we run out-of-space is: in f2fs_map_blocks(), f2fs may trigger foreground gc only if it allocates any physical block, it will be a little bit later when there is multiple threads writing data w/ aio/dio/bufio method in parallel, since we always use OPU in lfs mode, so f2fs_map_blocks() does block allocations aggressively.
In order to fix this issue, let's give a chance to trigger foreground gc in prior to block allocation in f2fs_map_blocks().
Fixes: 36abef4e796d ("f2fs: introduce mode=lfs mount option") Cc: Daeho Jeong daehojeong@google.com Signed-off-by: Chao Yu chao@kernel.org Signed-off-by: Jaegeuk Kim jaegeuk@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- fs/f2fs/data.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c index 942f358126e6..d37104aa847a 100644 --- a/fs/f2fs/data.c +++ b/fs/f2fs/data.c @@ -1552,8 +1552,11 @@ int f2fs_map_blocks(struct inode *inode, struct f2fs_map_blocks *map, int flag) end = pgofs + maxblocks;
next_dnode: - if (map->m_may_create) + if (map->m_may_create) { + if (f2fs_lfs_mode(sbi)) + f2fs_balance_fs(sbi, true); f2fs_map_lock(sbi, flag); + }
/* When reading holes, we need its node page */ set_new_dnode(&dn, inode, NULL, NULL, 0);