ksmbd: don't increment epoch if current state and request state are same

If existing lease state and request state are same, don't increment
epoch in create context.
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>

fs/smb/server/oplock.c

@@ -105,7 +105,7 @@ static int alloc_lease(struct oplock_info *opinfo, struct lease_ctx_info *lctx)
 	lease->is_dir = lctx->is_dir;
 	memcpy(lease->parent_lease_key, lctx->parent_lease_key, SMB2_LEASE_KEY_SIZE);
 	lease->version = lctx->version;
-	lease->epoch = le16_to_cpu(lctx->epoch);
+	lease->epoch = le16_to_cpu(lctx->epoch) + 1;
 	INIT_LIST_HEAD(&opinfo->lease_entry);
 	opinfo->o_lease = lease;
 
@@ -541,6 +541,9 @@ static struct oplock_info *same_client_has_lease(struct ksmbd_inode *ci,
 				continue;
 			}
 
+			if (lctx->req_state != lease->state)
+				lease->epoch++;
+
 			/* upgrading lease */
 			if ((atomic_read(&ci->op_count) +
 			     atomic_read(&ci->sop_count)) == 1) {
@@ -1035,7 +1038,7 @@ static void copy_lease(struct oplock_info *op1, struct oplock_info *op2)
 	       SMB2_LEASE_KEY_SIZE);
 	lease2->duration = lease1->duration;
 	lease2->flags = lease1->flags;
-	lease2->epoch = lease1->epoch++;
+	lease2->epoch = lease1->epoch;
 	lease2->version = lease1->version;
 }
 
@@ -1448,7 +1451,7 @@ void create_lease_buf(u8 *rbuf, struct lease *lease)
 		memcpy(buf->lcontext.LeaseKey, lease->lease_key,
 		       SMB2_LEASE_KEY_SIZE);
 		buf->lcontext.LeaseFlags = lease->flags;
-		buf->lcontext.Epoch = cpu_to_le16(++lease->epoch);
+		buf->lcontext.Epoch = cpu_to_le16(lease->epoch);
 		buf->lcontext.LeaseState = lease->state;
 		memcpy(buf->lcontext.ParentLeaseKey, lease->parent_lease_key,
 		       SMB2_LEASE_KEY_SIZE);