ceph: move encode_fh to new API

Use parent_inode has a flag for whether nfsd wants a connectable fh, but
generate one opportunistically so that we can take advantage of the
additional info in there.

Signed-off-by: Sage Weil <sage@newdream.net>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 21 insertions, 13 deletions

diff --git a/fs/ceph/export.c b/fs/ceph/export.c
index 4f9234c6da61..8e1b60e557b6 100644
--- a/fs/ceph/export.c
+++ b/fs/ceph/export.c
@@ -40,38 +40,49 @@ struct ceph_nfs_confh {
         u32 parent_name_hash;
 } __attribute__ ((packed));
 
-static int ceph_encode_fh(struct dentry *dentry, u32 *rawfh, int *max_len,
-                          int connectable)
+/*
+ * The presence of @parent_inode here tells us whether NFS wants a
+ * connectable file handle.  However, we want to make a connectionable
+ * file handle unconditionally so that the MDS gets as much of a hint
+ * as possible.  That means we only use @parent_dentry to indicate
+ * whether nfsd wants a connectable fh, and whether we should indicate
+ * failure from a too-small @max_len.
+ */
+static int ceph_encode_fh(struct inode *inode, u32 *rawfh, int *max_len,
+                          struct inode *parent_inode)
 {
         int type;
         struct ceph_nfs_fh *fh = (void *)rawfh;
         struct ceph_nfs_confh *cfh = (void *)rawfh;
-        struct dentry *parent;
-        struct inode *inode = dentry->d_inode;
         int connected_handle_length = sizeof(*cfh)/4;
         int handle_length = sizeof(*fh)/4;
+        struct dentry *dentry = d_find_alias(inode);
+        struct dentry *parent;
 
         /* don't re-export snaps */
         if (ceph_snap(inode) != CEPH_NOSNAP)
                 return -EINVAL;
 
-        spin_lock(&dentry->d_lock);
-        parent = dentry->d_parent;
-        if (*max_len >= connected_handle_length) {
+        /* if we found an alias, generate a connectable fh */
+        if (*max_len >= connected_handle_length && dentry) {
                 dout("encode_fh %p connectable\n", dentry);
-                cfh->ino = ceph_ino(dentry->d_inode);
+                spin_lock(&dentry->d_lock);
+                parent = dentry->d_parent;
+                cfh->ino = ceph_ino(inode);
                 cfh->parent_ino = ceph_ino(parent->d_inode);
                 cfh->parent_name_hash = ceph_dentry_hash(parent->d_inode,
                                                          dentry);
                 *max_len = connected_handle_length;
                 type = 2;
+                spin_unlock(&dentry->d_lock);
         } else if (*max_len >= handle_length) {
-                if (connectable) {
+                if (parent_inode) {
+                        /* nfsd wants connectable */
                         *max_len = connected_handle_length;
                         type = 255;
                 } else {
                         dout("encode_fh %p\n", dentry);
-                        fh->ino = ceph_ino(dentry->d_inode);
+                        fh->ino = ceph_ino(inode);
                         *max_len = handle_length;
                         type = 1;
                 }
@@ -79,7 +90,6 @@ static int ceph_encode_fh(struct dentry *dentry, u32 *rawfh, int *max_len,
                 *max_len = handle_length;
                 type = 255;
         }
-        spin_unlock(&dentry->d_lock);
         return type;
 }
 
@@ -247,9 +257,7 @@ static struct dentry *ceph_fh_to_parent(struct super_block *sb,
 }
 
 const struct export_operations ceph_export_ops = {
-#ifdef CEPH_BREAKAGE_FIXED
         .encode_fh = ceph_encode_fh,
-#endif
         .fh_to_dentry = ceph_fh_to_dentry,
         .fh_to_parent = ceph_fh_to_parent,
 };