From: Wengang Wang wen.gang.wang@oracle.com Subject: ocfs2: free up write context when direct IO failed

The write context should also be freed even when direct IO failed. Otherwise a memory leak is introduced and entries remain in oi->ip_unwritten_list causing the following BUG later in unlink path:

ERROR: bug expression: !list_empty(&oi->ip_unwritten_list) ERROR: Clear inode of 215043, inode has unwritten extents ... Call Trace: ? __set_current_blocked+0x42/0x68 ocfs2_evict_inode+0x91/0x6a0 [ocfs2] ? bit_waitqueue+0x40/0x33 evict+0xdb/0x1af iput+0x1a2/0x1f7 do_unlinkat+0x194/0x28f SyS_unlinkat+0x1b/0x2f do_syscall_64+0x79/0x1ae entry_SYSCALL_64_after_hwframe+0x151/0x0

This patch also logs, with frequency limit, direct IO failures.

Link: http://lkml.kernel.org/r/20181102170632.25921-1-wen.gang.wang@oracle.com Signed-off-by: Wengang Wang wen.gang.wang@oracle.com Reviewed-by: Junxiao Bi junxiao.bi@oracle.com Reviewed-by: Changwei Ge ge.changwei@h3c.com Reviewed-by: Joseph Qi jiangqi903@gmail.com Cc: Mark Fasheh mark@fasheh.com Cc: Joel Becker jlbec@evilplan.org Cc: stable@vger.kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org ---

--- a/fs/ocfs2/aops.c~ocfs2-free-up-write-context-when-direct-io-failed +++ a/fs/ocfs2/aops.c @@ -2411,8 +2411,16 @@ static int ocfs2_dio_end_io(struct kiocb /* this io's submitter should not have unlocked this before we could */ BUG_ON(!ocfs2_iocb_is_rw_locked(iocb));

- if (bytes > 0 && private) - ret = ocfs2_dio_end_io_write(inode, private, offset, bytes); + if (bytes <= 0) + mlog_ratelimited(ML_ERROR, "Direct IO failed, bytes = %lld", + (long long)bytes); + if (private) { + if (bytes > 0) + ret = ocfs2_dio_end_io_write(inode, private, offset, + bytes); + else + ocfs2_dio_free_write_ctx(inode, private); + }

ocfs2_iocb_clear_rw_locked(iocb);

--- a/fs/ocfs2/cluster/masklog.h~ocfs2-free-up-write-context-when-direct-io-failed +++ a/fs/ocfs2/cluster/masklog.h @@ -178,6 +178,15 @@ do { \ ##__VA_ARGS__); \ } while (0)

+#define mlog_ratelimited(mask, fmt, ...) \ +do { \ + static DEFINE_RATELIMIT_STATE(_rs, \ + DEFAULT_RATELIMIT_INTERVAL, \ + DEFAULT_RATELIMIT_BURST); \ + if (__ratelimit(&_rs)) \ + mlog(mask, fmt, ##__VA_ARGS__); \ +} while (0) + #define mlog_errno(st) ({ \ int _st = (st); \ if (_st != -ERESTARTSYS && _st != -EINTR && \ _