On Wed, Aug 26, 2015 at 03:11:40PM -0700, Andrew Morton wrote: > From: WeiWei Wang <wangww...@huawei.com> > Subject: ocfs2: add ip_alloc_sem in direct IO to protect allocation changes > > In ocfs2, ip_alloc_sem is used to protect allocation changes on the node. > In direct IO, we add ip_alloc_sem to protect date consistent between > direct-io and ocfs2_truncate_file race (buffer io use ip_alloc_sem > already). Although inode->i_mutex lock is used to avoid concurrency of > above situation, i think ip_alloc_sem is still needed because protect > allocation changes is significant. > > Other filesystem like ext4 also uses rw_semaphore to protect data > consistent between get_block-vs-truncate race by other means, So > ip_alloc_sem in ocfs2 direct io is needed. > > Signed-off-by: Weiwei Wang <wangww...@huawei.com> > Cc: Mark Fasheh <mfas...@suse.com> > Cc: Joel Becker <jl...@evilplan.org> > Signed-off-by: Andrew Morton <a...@linux-foundation.org>
Signed-off-by: Mark Fasheh <mfas...@suse.de> -- Mark Fasheh _______________________________________________ Ocfs2-devel mailing list Ocfs2-devel@oss.oracle.com https://oss.oracle.com/mailman/listinfo/ocfs2-devel
