dlm: reject normal unlock when lock is waiting for lookup
[safe/jmp/linux-2.6] / fs / dlm / lock.c
index 43ca2a3..fa68e9b 100644 (file)
@@ -1,7 +1,7 @@
 /******************************************************************************
 *******************************************************************************
 **
-**  Copyright (C) 2005-2007 Red Hat, Inc.  All rights reserved.
+**  Copyright (C) 2005-2008 Red Hat, Inc.  All rights reserved.
 **
 **  This copyrighted material is made available to anyone wishing to use,
 **  modify, copy, or redistribute it subject to the terms and conditions
@@ -1940,8 +1940,11 @@ static void confirm_master(struct dlm_rsb *r, int error)
                break;
 
        case -EAGAIN:
-               /* the remote master didn't queue our NOQUEUE request;
-                  make a waiting lkb the first_lkid */
+       case -EBADR:
+       case -ENOTBLK:
+               /* the remote request failed and won't be retried (it was
+                  a NOQUEUE, or has been canceled/unlocked); make a waiting
+                  lkb the first_lkid */
 
                r->res_first_lkid = 0;
 
@@ -2107,17 +2110,18 @@ static int validate_unlock_args(struct dlm_lkb *lkb, struct dlm_args *args)
        /* an lkb may be waiting for an rsb lookup to complete where the
           lookup was initiated by another lock */
 
-       if (args->flags & (DLM_LKF_CANCEL | DLM_LKF_FORCEUNLOCK)) {
-               if (!list_empty(&lkb->lkb_rsb_lookup)) {
+       if (!list_empty(&lkb->lkb_rsb_lookup)) {
+               if (args->flags & (DLM_LKF_CANCEL | DLM_LKF_FORCEUNLOCK)) {
                        log_debug(ls, "unlock on rsb_lookup %x", lkb->lkb_id);
                        list_del_init(&lkb->lkb_rsb_lookup);
                        queue_cast(lkb->lkb_resource, lkb,
                                   args->flags & DLM_LKF_CANCEL ?
                                   -DLM_ECANCEL : -DLM_EUNLOCK);
                        unhold_lkb(lkb); /* undoes create_lkb() */
-                       rv = -EBUSY;
-                       goto out;
                }
+               /* caller changes -EBUSY to 0 for CANCEL and FORCEUNLOCK */
+               rv = -EBUSY;
+               goto out;
        }
 
        /* cancel not allowed with another cancel/unlock in progress */
@@ -3005,8 +3009,6 @@ static int receive_request_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
        lkb->lkb_bastaddr = (void *) (long) (ms->m_asts & AST_BAST);
        lkb->lkb_astaddr = (void *) (long) (ms->m_asts & AST_COMP);
 
-       DLM_ASSERT(is_master_copy(lkb), dlm_print_lkb(lkb););
-
        if (lkb->lkb_exflags & DLM_LKF_VALBLK) {
                /* lkb was just created so there won't be an lvb yet */
                lkb->lkb_lvbptr = dlm_allocate_lvb(ls);
@@ -3020,16 +3022,6 @@ static int receive_request_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
 static int receive_convert_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
                                struct dlm_message *ms)
 {
-       if (lkb->lkb_nodeid != ms->m_header.h_nodeid) {
-               log_error(ls, "convert_args nodeid %d %d lkid %x %x",
-                         lkb->lkb_nodeid, ms->m_header.h_nodeid,
-                         lkb->lkb_id, lkb->lkb_remid);
-               return -EINVAL;
-       }
-
-       if (!is_master_copy(lkb))
-               return -EINVAL;
-
        if (lkb->lkb_status != DLM_LKSTS_GRANTED)
                return -EBUSY;
 
@@ -3045,8 +3037,6 @@ static int receive_convert_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
 static int receive_unlock_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
                               struct dlm_message *ms)
 {
-       if (!is_master_copy(lkb))
-               return -EINVAL;
        if (receive_lvb(ls, lkb, ms))
                return -ENOMEM;
        return 0;
@@ -3062,6 +3052,50 @@ static void setup_stub_lkb(struct dlm_ls *ls, struct dlm_message *ms)
        lkb->lkb_remid = ms->m_lkid;
 }
 
+/* This is called after the rsb is locked so that we can safely inspect
+   fields in the lkb. */
+
+static int validate_message(struct dlm_lkb *lkb, struct dlm_message *ms)
+{
+       int from = ms->m_header.h_nodeid;
+       int error = 0;
+
+       switch (ms->m_type) {
+       case DLM_MSG_CONVERT:
+       case DLM_MSG_UNLOCK:
+       case DLM_MSG_CANCEL:
+               if (!is_master_copy(lkb) || lkb->lkb_nodeid != from)
+                       error = -EINVAL;
+               break;
+
+       case DLM_MSG_CONVERT_REPLY:
+       case DLM_MSG_UNLOCK_REPLY:
+       case DLM_MSG_CANCEL_REPLY:
+       case DLM_MSG_GRANT:
+       case DLM_MSG_BAST:
+               if (!is_process_copy(lkb) || lkb->lkb_nodeid != from)
+                       error = -EINVAL;
+               break;
+
+       case DLM_MSG_REQUEST_REPLY:
+               if (!is_process_copy(lkb))
+                       error = -EINVAL;
+               else if (lkb->lkb_nodeid != -1 && lkb->lkb_nodeid != from)
+                       error = -EINVAL;
+               break;
+
+       default:
+               error = -EINVAL;
+       }
+
+       if (error)
+               log_error(lkb->lkb_resource->res_ls,
+                         "ignore invalid message %d from %d %x %x %x %d",
+                         ms->m_type, from, lkb->lkb_id, lkb->lkb_remid,
+                         lkb->lkb_flags, lkb->lkb_nodeid);
+       return error;
+}
+
 static void receive_request(struct dlm_ls *ls, struct dlm_message *ms)
 {
        struct dlm_lkb *lkb;
@@ -3123,17 +3157,21 @@ static void receive_convert(struct dlm_ls *ls, struct dlm_message *ms)
        hold_rsb(r);
        lock_rsb(r);
 
+       error = validate_message(lkb, ms);
+       if (error)
+               goto out;
+
        receive_flags(lkb, ms);
        error = receive_convert_args(ls, lkb, ms);
        if (error)
-               goto out;
+               goto out_reply;
        reply = !down_conversion(lkb);
 
        error = do_convert(r, lkb);
- out:
+ out_reply:
        if (reply)
                send_convert_reply(r, lkb, error);
-
+ out:
        unlock_rsb(r);
        put_rsb(r);
        dlm_put_lkb(lkb);
@@ -3159,15 +3197,19 @@ static void receive_unlock(struct dlm_ls *ls, struct dlm_message *ms)
        hold_rsb(r);
        lock_rsb(r);
 
+       error = validate_message(lkb, ms);
+       if (error)
+               goto out;
+
        receive_flags(lkb, ms);
        error = receive_unlock_args(ls, lkb, ms);
        if (error)
-               goto out;
+               goto out_reply;
 
        error = do_unlock(r, lkb);
- out:
+ out_reply:
        send_unlock_reply(r, lkb, error);
-
+ out:
        unlock_rsb(r);
        put_rsb(r);
        dlm_put_lkb(lkb);
@@ -3195,9 +3237,13 @@ static void receive_cancel(struct dlm_ls *ls, struct dlm_message *ms)
        hold_rsb(r);
        lock_rsb(r);
 
+       error = validate_message(lkb, ms);
+       if (error)
+               goto out;
+
        error = do_cancel(r, lkb);
        send_cancel_reply(r, lkb, error);
-
+ out:
        unlock_rsb(r);
        put_rsb(r);
        dlm_put_lkb(lkb);
@@ -3216,22 +3262,26 @@ static void receive_grant(struct dlm_ls *ls, struct dlm_message *ms)
 
        error = find_lkb(ls, ms->m_remid, &lkb);
        if (error) {
-               log_error(ls, "receive_grant no lkb");
+               log_debug(ls, "receive_grant from %d no lkb %x",
+                         ms->m_header.h_nodeid, ms->m_remid);
                return;
        }
-       DLM_ASSERT(is_process_copy(lkb), dlm_print_lkb(lkb););
 
        r = lkb->lkb_resource;
 
        hold_rsb(r);
        lock_rsb(r);
 
+       error = validate_message(lkb, ms);
+       if (error)
+               goto out;
+
        receive_flags_reply(lkb, ms);
        if (is_altmode(lkb))
                munge_altmode(lkb, ms);
        grant_lock_pc(r, lkb, ms);
        queue_cast(r, lkb, 0);
-
+ out:
        unlock_rsb(r);
        put_rsb(r);
        dlm_put_lkb(lkb);
@@ -3245,18 +3295,22 @@ static void receive_bast(struct dlm_ls *ls, struct dlm_message *ms)
 
        error = find_lkb(ls, ms->m_remid, &lkb);
        if (error) {
-               log_error(ls, "receive_bast no lkb");
+               log_debug(ls, "receive_bast from %d no lkb %x",
+                         ms->m_header.h_nodeid, ms->m_remid);
                return;
        }
-       DLM_ASSERT(is_process_copy(lkb), dlm_print_lkb(lkb););
 
        r = lkb->lkb_resource;
 
        hold_rsb(r);
        lock_rsb(r);
 
-       queue_bast(r, lkb, ms->m_bastmode);
+       error = validate_message(lkb, ms);
+       if (error)
+               goto out;
 
+       queue_bast(r, lkb, ms->m_bastmode);
+ out:
        unlock_rsb(r);
        put_rsb(r);
        dlm_put_lkb(lkb);
@@ -3322,15 +3376,19 @@ static void receive_request_reply(struct dlm_ls *ls, struct dlm_message *ms)
 
        error = find_lkb(ls, ms->m_remid, &lkb);
        if (error) {
-               log_error(ls, "receive_request_reply no lkb");
+               log_debug(ls, "receive_request_reply from %d no lkb %x",
+                         ms->m_header.h_nodeid, ms->m_remid);
                return;
        }
-       DLM_ASSERT(is_process_copy(lkb), dlm_print_lkb(lkb););
 
        r = lkb->lkb_resource;
        hold_rsb(r);
        lock_rsb(r);
 
+       error = validate_message(lkb, ms);
+       if (error)
+               goto out;
+
        mstype = lkb->lkb_wait_type;
        error = remove_from_waiters(lkb, DLM_MSG_REQUEST_REPLY);
        if (error)
@@ -3382,6 +3440,7 @@ static void receive_request_reply(struct dlm_ls *ls, struct dlm_message *ms)
                if (is_overlap(lkb)) {
                        /* we'll ignore error in cancel/unlock reply */
                        queue_cast_overlap(r, lkb);
+                       confirm_master(r, result);
                        unhold_lkb(lkb); /* undoes create_lkb() */
                } else
                        _request_lock(r, lkb);
@@ -3462,6 +3521,10 @@ static void _receive_convert_reply(struct dlm_lkb *lkb, struct dlm_message *ms)
        hold_rsb(r);
        lock_rsb(r);
 
+       error = validate_message(lkb, ms);
+       if (error)
+               goto out;
+
        /* stub reply can happen with waiters_mutex held */
        error = remove_from_waiters_ms(lkb, ms);
        if (error)
@@ -3480,10 +3543,10 @@ static void receive_convert_reply(struct dlm_ls *ls, struct dlm_message *ms)
 
        error = find_lkb(ls, ms->m_remid, &lkb);
        if (error) {
-               log_error(ls, "receive_convert_reply no lkb");
+               log_debug(ls, "receive_convert_reply from %d no lkb %x",
+                         ms->m_header.h_nodeid, ms->m_remid);
                return;
        }
-       DLM_ASSERT(is_process_copy(lkb), dlm_print_lkb(lkb););
 
        _receive_convert_reply(lkb, ms);
        dlm_put_lkb(lkb);
@@ -3497,6 +3560,10 @@ static void _receive_unlock_reply(struct dlm_lkb *lkb, struct dlm_message *ms)
        hold_rsb(r);
        lock_rsb(r);
 
+       error = validate_message(lkb, ms);
+       if (error)
+               goto out;
+
        /* stub reply can happen with waiters_mutex held */
        error = remove_from_waiters_ms(lkb, ms);
        if (error)
@@ -3528,10 +3595,10 @@ static void receive_unlock_reply(struct dlm_ls *ls, struct dlm_message *ms)
 
        error = find_lkb(ls, ms->m_remid, &lkb);
        if (error) {
-               log_error(ls, "receive_unlock_reply no lkb");
+               log_debug(ls, "receive_unlock_reply from %d no lkb %x",
+                         ms->m_header.h_nodeid, ms->m_remid);
                return;
        }
-       DLM_ASSERT(is_process_copy(lkb), dlm_print_lkb(lkb););
 
        _receive_unlock_reply(lkb, ms);
        dlm_put_lkb(lkb);
@@ -3545,6 +3612,10 @@ static void _receive_cancel_reply(struct dlm_lkb *lkb, struct dlm_message *ms)
        hold_rsb(r);
        lock_rsb(r);
 
+       error = validate_message(lkb, ms);
+       if (error)
+               goto out;
+
        /* stub reply can happen with waiters_mutex held */
        error = remove_from_waiters_ms(lkb, ms);
        if (error)
@@ -3576,10 +3647,10 @@ static void receive_cancel_reply(struct dlm_ls *ls, struct dlm_message *ms)
 
        error = find_lkb(ls, ms->m_remid, &lkb);
        if (error) {
-               log_error(ls, "receive_cancel_reply no lkb");
+               log_debug(ls, "receive_cancel_reply from %d no lkb %x",
+                         ms->m_header.h_nodeid, ms->m_remid);
                return;
        }
-       DLM_ASSERT(is_process_copy(lkb), dlm_print_lkb(lkb););
 
        _receive_cancel_reply(lkb, ms);
        dlm_put_lkb(lkb);
@@ -3639,6 +3710,13 @@ static void receive_lookup_reply(struct dlm_ls *ls, struct dlm_message *ms)
 
 static void _receive_message(struct dlm_ls *ls, struct dlm_message *ms)
 {
+       if (!dlm_is_member(ls, ms->m_header.h_nodeid)) {
+               log_debug(ls, "ignore non-member message %d from %d %x %x %d",
+                         ms->m_type, ms->m_header.h_nodeid, ms->m_lkid,
+                         ms->m_remid, ms->m_result);
+               return;
+       }
+
        switch (ms->m_type) {
 
        /* messages sent to a master node */
@@ -3805,6 +3883,7 @@ static void recover_convert_waiter(struct dlm_ls *ls, struct dlm_lkb *lkb)
                ls->ls_stub_ms.m_type = DLM_MSG_CONVERT_REPLY;
                ls->ls_stub_ms.m_result = -EINPROGRESS;
                ls->ls_stub_ms.m_flags = lkb->lkb_flags;
+               ls->ls_stub_ms.m_header.h_nodeid = lkb->lkb_nodeid;
                _receive_convert_reply(lkb, &ls->ls_stub_ms);
 
                /* Same special case as in receive_rcom_lock_args() */
@@ -3846,6 +3925,7 @@ static int waiter_needs_recovery(struct dlm_ls *ls, struct dlm_lkb *lkb)
 void dlm_recover_waiters_pre(struct dlm_ls *ls)
 {
        struct dlm_lkb *lkb, *safe;
+       int wait_type, stub_unlock_result, stub_cancel_result;
 
        mutex_lock(&ls->ls_waiters_mutex);
 
@@ -3864,7 +3944,33 @@ void dlm_recover_waiters_pre(struct dlm_ls *ls)
                if (!waiter_needs_recovery(ls, lkb))
                        continue;
 
-               switch (lkb->lkb_wait_type) {
+               wait_type = lkb->lkb_wait_type;
+               stub_unlock_result = -DLM_EUNLOCK;
+               stub_cancel_result = -DLM_ECANCEL;
+
+               /* Main reply may have been received leaving a zero wait_type,
+                  but a reply for the overlapping op may not have been
+                  received.  In that case we need to fake the appropriate
+                  reply for the overlap op. */
+
+               if (!wait_type) {
+                       if (is_overlap_cancel(lkb)) {
+                               wait_type = DLM_MSG_CANCEL;
+                               if (lkb->lkb_grmode == DLM_LOCK_IV)
+                                       stub_cancel_result = 0;
+                       }
+                       if (is_overlap_unlock(lkb)) {
+                               wait_type = DLM_MSG_UNLOCK;
+                               if (lkb->lkb_grmode == DLM_LOCK_IV)
+                                       stub_unlock_result = -ENOENT;
+                       }
+
+                       log_debug(ls, "rwpre overlap %x %x %d %d %d",
+                                 lkb->lkb_id, lkb->lkb_flags, wait_type,
+                                 stub_cancel_result, stub_unlock_result);
+               }
+
+               switch (wait_type) {
 
                case DLM_MSG_REQUEST:
                        lkb->lkb_flags |= DLM_IFL_RESEND;
@@ -3877,8 +3983,9 @@ void dlm_recover_waiters_pre(struct dlm_ls *ls)
                case DLM_MSG_UNLOCK:
                        hold_lkb(lkb);
                        ls->ls_stub_ms.m_type = DLM_MSG_UNLOCK_REPLY;
-                       ls->ls_stub_ms.m_result = -DLM_EUNLOCK;
+                       ls->ls_stub_ms.m_result = stub_unlock_result;
                        ls->ls_stub_ms.m_flags = lkb->lkb_flags;
+                       ls->ls_stub_ms.m_header.h_nodeid = lkb->lkb_nodeid;
                        _receive_unlock_reply(lkb, &ls->ls_stub_ms);
                        dlm_put_lkb(lkb);
                        break;
@@ -3886,15 +3993,16 @@ void dlm_recover_waiters_pre(struct dlm_ls *ls)
                case DLM_MSG_CANCEL:
                        hold_lkb(lkb);
                        ls->ls_stub_ms.m_type = DLM_MSG_CANCEL_REPLY;
-                       ls->ls_stub_ms.m_result = -DLM_ECANCEL;
+                       ls->ls_stub_ms.m_result = stub_cancel_result;
                        ls->ls_stub_ms.m_flags = lkb->lkb_flags;
+                       ls->ls_stub_ms.m_header.h_nodeid = lkb->lkb_nodeid;
                        _receive_cancel_reply(lkb, &ls->ls_stub_ms);
                        dlm_put_lkb(lkb);
                        break;
 
                default:
-                       log_error(ls, "invalid lkb wait_type %d",
-                                 lkb->lkb_wait_type);
+                       log_error(ls, "invalid lkb wait_type %d %d",
+                                 lkb->lkb_wait_type, wait_type);
                }
                schedule();
        }