From: Al Viro Date: Wed, 8 Apr 2015 21:00:32 +0000 (-0400) Subject: ocfs2: _really_ sync the right range X-Git-Tag: v3.2.69~48 X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?p=pandora-kernel.git;a=commitdiff_plain;h=dc6f158c9cea7ff050d79f8f6870eb0362fa4f0c;ds=sidebyside ocfs2: _really_ sync the right range commit 64b4e2526d1cf6e6a4db6213d6e2b6e6ab59479a upstream. "ocfs2 syncs the wrong range" had been broken; prior to it the code was doing the wrong thing in case of O_APPEND, all right, but _after_ it we were syncing the wrong range in 100% cases. *ppos, aka iocb->ki_pos is incremented prior to that point, so we are always doing sync on the area _after_ the one we'd written to. Spotted by Joseph Qi back in January; unfortunately, I'd missed his mail back then ;-/ Signed-off-by: Al Viro Signed-off-by: Ben Hutchings --- diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c index 0de24a2eea7f..6a7a3d9a56b8 100644 --- a/fs/ocfs2/file.c +++ b/fs/ocfs2/file.c @@ -2387,10 +2387,14 @@ out_dio: /* buffered aio wouldn't have proper lock coverage today */ BUG_ON(ret == -EIOCBQUEUED && !(file->f_flags & O_DIRECT)); + if (unlikely(written <= 0)) + goto no_sync; + if (((file->f_flags & O_DSYNC) && !direct_io) || IS_SYNC(inode) || ((file->f_flags & O_DIRECT) && !direct_io)) { - ret = filemap_fdatawrite_range(file->f_mapping, *ppos, - *ppos + count - 1); + ret = filemap_fdatawrite_range(file->f_mapping, + iocb->ki_pos - written, + iocb->ki_pos - 1); if (ret < 0) written = ret; @@ -2403,10 +2407,12 @@ out_dio: } if (!ret) - ret = filemap_fdatawait_range(file->f_mapping, *ppos, - *ppos + count - 1); + ret = filemap_fdatawait_range(file->f_mapping, + iocb->ki_pos - written, + iocb->ki_pos - 1); } +no_sync: /* * deep in g_f_a_w_n()->ocfs2_direct_IO we pass in a ocfs2_dio_end_io * function pointer which is called when o_direct io completes so that