From: Kotresh HR <khiremat@redhat.com>
Date: Tue, 25 Feb 2025 12:27:41 +0000 (+0530)
Subject: multi-mds/unlink: Referent inode - reverse link mgmt
X-Git-Tag: v20.3.0~377^2~21
X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=236a4b7b046a717e84879dcd535c0e1fefceab0d;p=ceph.git

multi-mds/unlink: Referent inode - reverse link mgmt

On unlink of the secondary hardlink with referent
inode, remove the referent inode from the referent_inodes
list of the primary/real inode. This patch handles the
multi-mds scenario where the auth of the primary/real
inode is different from the dentry auth of the secondary
hardlink (also the referent inode auth)

Fixes: https://tracker.ceph.com/issues/54205
Signed-off-by: Kotresh HR <khiremat@redhat.com>
---

diff --git a/src/mds/Server.cc b/src/mds/Server.cc
index 5ff75fc969d..5307cbfef39 100644
--- a/src/mds/Server.cc
+++ b/src/mds/Server.cc
@@ -7899,11 +7899,21 @@ void Server::_link_remote(const MDRequestRef& mdr, bool inc, CDentry *dn, CInode
     auto req = make_message<MMDSPeerRequest>(mdr->reqid, mdr->attempt, op);
     targeti->set_object_info(req->get_object_info());
     req->op_stamp = mdr->get_op_stamp();
+    // referent inode related
+    req->referent_ino = inodeno_t(0);
     if (mds->mdsmap->allow_referent_inodes()) {
-      if (inc && newi)
+      if (inc && newi) {
         req->referent_ino = newi->ino();
-    } else {
-      req->referent_ino = inodeno_t(0);
+        dout(20) << __func__ << " link - referent_ino= " << req->referent_ino << " sending over wire" << dendl;
+      }
+      else { //unlink
+        if (dnl->is_referent_remote()) {
+          CInode *ref_in = dnl->get_referent_inode();
+          ceph_assert(ref_in->is_auth());
+	  req->referent_ino = ref_in->ino();
+          dout(20) << __func__ << " unlink - referent_ino= " << req->referent_ino << " sending over wire" << dendl;
+        }
+      }
     }
 
     if (auto& desti_srnode = mdr->more()->desti_srnode)
@@ -8145,6 +8155,14 @@ void Server::handle_peer_link_prep(const MDRequestRef& mdr)
   } else {
     inc = false;
     pi.inode->nlink--;
+
+    if (referent_ino > 0) {
+      // Remove referent inode from primary inode (targeti)
+      pi.inode->remove_referent_ino(referent_ino);
+      dout(20) << __func__ <<  " referent_inodes " << std::hex << pi.inode->get_referent_inodes()
+               << " referent ino removed " << referent_ino << dendl;
+    }
+
     if (targeti->is_projected_snaprealm_global()) {
       ceph_assert(mdr->peer_request->desti_snapbl.length());
       auto p = mdr->peer_request->desti_snapbl.cbegin();