On Mar 6, 2014, at 9:16, Yan, Zheng <zheng.z.yan@xxxxxxxxx> wrote: > From: David Howells <dhowells@xxxxxxxxxx> > > Make __d_materialise_dentry() set the materialised dentry name correctly by > flipping the arguments to switch_names(). > > switch_names() is lazy: if both names are internal to their dentries, it'll > overwrite that of the first dentry with that of the second, and won't update > that of the second. > > In the case of __d_materialise_dentry(), the second is an already extant > anonymous dentry that we want to insert into the tree in place of the dentry we > just looked up[*]. However, the dentry we just looked up carries the name we > actually want to use. > > [*] This is used by NFS to join a mount of a subtree into a mount of a tree > nearer the root when the two meet, where both mounts share a superblock and > thus a set of dentries. > > Signed-off-by: David Howells <dhowells@xxxxxxxxxx> > --- > fs/dcache.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/fs/dcache.c b/fs/dcache.c > index 265e0ce..ff779d4 100644 > --- a/fs/dcache.c > +++ b/fs/dcache.c > @@ -2698,7 +2698,7 @@ static void __d_materialise_dentry(struct dentry *dentry, struct dentry *anon) > > dparent = dentry->d_parent; > > - switch_names(dentry, anon); > + switch_names(anon, dentry); > swap(dentry->d_name.hash, anon->d_name.hash); > > dentry->d_parent = dentry; Well spotted... We ought to better document the fact that ’switch_names’ is asymmetrical. Perhaps change it to ‘update_target_name’, and then switch the argument names so that the ’target’ really is the thing that gets updated? _________________________________ Trond Myklebust Linux NFS client maintainer, PrimaryData trond.myklebust@xxxxxxxxxxxxxxx -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
