vfs: make it possible to access the dentry hash/len as one 64-bit entry
This allows comparing hash and len in one operation on 64-bit
architectures. Right now only __d_lookup_rcu() takes advantage of this,
since that is the case we care most about.
The use of anonymous struct/unions hides the alternate 64-bit approach
from most users, the exception being a few cases where we initialize a
'struct qstr' with a static initializer. This makes the problematic
cases use a new QSTR_INIT() helper function for that (but initializing
just the name pointer with a "{ .name = xyzzy }" initializer remains
valid, as does just copying another qstr structure).
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
index 349d7b3..e2a3f4b 100644
--- a/fs/ext4/namei.c
+++ b/fs/ext4/namei.c
@@ -1052,10 +1052,7 @@
struct dentry *ext4_get_parent(struct dentry *child)
{
__u32 ino;
- static const struct qstr dotdot = {
- .name = "..",
- .len = 2,
- };
+ static const struct qstr dotdot = QSTR_INIT("..", 2);
struct ext4_dir_entry_2 * de;
struct buffer_head *bh;
