Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / fs / ocfs2 / dlm / dlmconvert.c
diff --git a/kernel/fs/ocfs2/dlm/dlmconvert.c b/kernel/fs/ocfs2/dlm/dlmconvert.c
new file mode 100644 (file)
index 0000000..e36d63f
--- /dev/null
@@ -0,0 +1,544 @@
+/* -*- mode: c; c-basic-offset: 8; -*-
+ * vim: noexpandtab sw=8 ts=8 sts=0:
+ *
+ * dlmconvert.c
+ *
+ * underlying calls for lock conversion
+ *
+ * Copyright (C) 2004 Oracle.  All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this program; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 021110-1307, USA.
+ *
+ */
+
+
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <linux/types.h>
+#include <linux/highmem.h>
+#include <linux/init.h>
+#include <linux/sysctl.h>
+#include <linux/random.h>
+#include <linux/blkdev.h>
+#include <linux/socket.h>
+#include <linux/inet.h>
+#include <linux/spinlock.h>
+
+
+#include "cluster/heartbeat.h"
+#include "cluster/nodemanager.h"
+#include "cluster/tcp.h"
+
+#include "dlmapi.h"
+#include "dlmcommon.h"
+
+#include "dlmconvert.h"
+
+#define MLOG_MASK_PREFIX ML_DLM
+#include "cluster/masklog.h"
+
+/* NOTE: __dlmconvert_master is the only function in here that
+ * needs a spinlock held on entry (res->spinlock) and it is the
+ * only one that holds a lock on exit (res->spinlock).
+ * All other functions in here need no locks and drop all of
+ * the locks that they acquire. */
+static enum dlm_status __dlmconvert_master(struct dlm_ctxt *dlm,
+                                          struct dlm_lock_resource *res,
+                                          struct dlm_lock *lock, int flags,
+                                          int type, int *call_ast,
+                                          int *kick_thread);
+static enum dlm_status dlm_send_remote_convert_request(struct dlm_ctxt *dlm,
+                                          struct dlm_lock_resource *res,
+                                          struct dlm_lock *lock, int flags, int type);
+
+/*
+ * this is only called directly by dlmlock(), and only when the
+ * local node is the owner of the lockres
+ * locking:
+ *   caller needs:  none
+ *   taken:         takes and drops res->spinlock
+ *   held on exit:  none
+ * returns: see __dlmconvert_master
+ */
+enum dlm_status dlmconvert_master(struct dlm_ctxt *dlm,
+                                 struct dlm_lock_resource *res,
+                                 struct dlm_lock *lock, int flags, int type)
+{
+       int call_ast = 0, kick_thread = 0;
+       enum dlm_status status;
+
+       spin_lock(&res->spinlock);
+       /* we are not in a network handler, this is fine */
+       __dlm_wait_on_lockres(res);
+       __dlm_lockres_reserve_ast(res);
+       res->state |= DLM_LOCK_RES_IN_PROGRESS;
+
+       status = __dlmconvert_master(dlm, res, lock, flags, type,
+                                    &call_ast, &kick_thread);
+
+       res->state &= ~DLM_LOCK_RES_IN_PROGRESS;
+       spin_unlock(&res->spinlock);
+       wake_up(&res->wq);
+       if (status != DLM_NORMAL && status != DLM_NOTQUEUED)
+               dlm_error(status);
+
+       /* either queue the ast or release it */
+       if (call_ast)
+               dlm_queue_ast(dlm, lock);
+       else
+               dlm_lockres_release_ast(dlm, res);
+
+       if (kick_thread)
+               dlm_kick_thread(dlm, res);
+
+       return status;
+}
+
+/* performs lock conversion at the lockres master site
+ * locking:
+ *   caller needs:  res->spinlock
+ *   taken:         takes and drops lock->spinlock
+ *   held on exit:  res->spinlock
+ * returns: DLM_NORMAL, DLM_NOTQUEUED, DLM_DENIED
+ *   call_ast: whether ast should be called for this lock
+ *   kick_thread: whether dlm_kick_thread should be called
+ */
+static enum dlm_status __dlmconvert_master(struct dlm_ctxt *dlm,
+                                          struct dlm_lock_resource *res,
+                                          struct dlm_lock *lock, int flags,
+                                          int type, int *call_ast,
+                                          int *kick_thread)
+{
+       enum dlm_status status = DLM_NORMAL;
+       struct dlm_lock *tmplock=NULL;
+
+       assert_spin_locked(&res->spinlock);
+
+       mlog(0, "type=%d, convert_type=%d, new convert_type=%d\n",
+            lock->ml.type, lock->ml.convert_type, type);
+
+       spin_lock(&lock->spinlock);
+
+       /* already converting? */
+       if (lock->ml.convert_type != LKM_IVMODE) {
+               mlog(ML_ERROR, "attempted to convert a lock with a lock "
+                    "conversion pending\n");
+               status = DLM_DENIED;
+               goto unlock_exit;
+       }
+
+       /* must be on grant queue to convert */
+       if (!dlm_lock_on_list(&res->granted, lock)) {
+               mlog(ML_ERROR, "attempted to convert a lock not on grant "
+                    "queue\n");
+               status = DLM_DENIED;
+               goto unlock_exit;
+       }
+
+       if (flags & LKM_VALBLK) {
+               switch (lock->ml.type) {
+                       case LKM_EXMODE:
+                               /* EX + LKM_VALBLK + convert == set lvb */
+                               mlog(0, "will set lvb: converting %s->%s\n",
+                                    dlm_lock_mode_name(lock->ml.type),
+                                    dlm_lock_mode_name(type));
+                               lock->lksb->flags |= DLM_LKSB_PUT_LVB;
+                               break;
+                       case LKM_PRMODE:
+                       case LKM_NLMODE:
+                               /* refetch if new level is not NL */
+                               if (type > LKM_NLMODE) {
+                                       mlog(0, "will fetch new value into "
+                                            "lvb: converting %s->%s\n",
+                                            dlm_lock_mode_name(lock->ml.type),
+                                            dlm_lock_mode_name(type));
+                                       lock->lksb->flags |= DLM_LKSB_GET_LVB;
+                               } else {
+                                       mlog(0, "will NOT fetch new value "
+                                            "into lvb: converting %s->%s\n",
+                                            dlm_lock_mode_name(lock->ml.type),
+                                            dlm_lock_mode_name(type));
+                                       flags &= ~(LKM_VALBLK);
+                               }
+                               break;
+               }
+       }
+
+
+       /* in-place downconvert? */
+       if (type <= lock->ml.type)
+               goto grant;
+
+       /* upconvert from here on */
+       status = DLM_NORMAL;
+       list_for_each_entry(tmplock, &res->granted, list) {
+               if (tmplock == lock)
+                       continue;
+               if (!dlm_lock_compatible(tmplock->ml.type, type))
+                       goto switch_queues;
+       }
+
+       list_for_each_entry(tmplock, &res->converting, list) {
+               if (!dlm_lock_compatible(tmplock->ml.type, type))
+                       goto switch_queues;
+               /* existing conversion requests take precedence */
+               if (!dlm_lock_compatible(tmplock->ml.convert_type, type))
+                       goto switch_queues;
+       }
+
+       /* fall thru to grant */
+
+grant:
+       mlog(0, "res %.*s, granting %s lock\n", res->lockname.len,
+            res->lockname.name, dlm_lock_mode_name(type));
+       /* immediately grant the new lock type */
+       lock->lksb->status = DLM_NORMAL;
+       if (lock->ml.node == dlm->node_num)
+               mlog(0, "doing in-place convert for nonlocal lock\n");
+       lock->ml.type = type;
+       if (lock->lksb->flags & DLM_LKSB_PUT_LVB)
+               memcpy(res->lvb, lock->lksb->lvb, DLM_LVB_LEN);
+
+       status = DLM_NORMAL;
+       *call_ast = 1;
+       goto unlock_exit;
+
+switch_queues:
+       if (flags & LKM_NOQUEUE) {
+               mlog(0, "failed to convert NOQUEUE lock %.*s from "
+                    "%d to %d...\n", res->lockname.len, res->lockname.name,
+                    lock->ml.type, type);
+               status = DLM_NOTQUEUED;
+               goto unlock_exit;
+       }
+       mlog(0, "res %.*s, queueing...\n", res->lockname.len,
+            res->lockname.name);
+
+       lock->ml.convert_type = type;
+       /* do not alter lock refcount.  switching lists. */
+       list_move_tail(&lock->list, &res->converting);
+
+unlock_exit:
+       spin_unlock(&lock->spinlock);
+       if (status == DLM_DENIED) {
+               __dlm_print_one_lock_resource(res);
+       }
+       if (status == DLM_NORMAL)
+               *kick_thread = 1;
+       return status;
+}
+
+void dlm_revert_pending_convert(struct dlm_lock_resource *res,
+                               struct dlm_lock *lock)
+{
+       /* do not alter lock refcount.  switching lists. */
+       list_move_tail(&lock->list, &res->granted);
+       lock->ml.convert_type = LKM_IVMODE;
+       lock->lksb->flags &= ~(DLM_LKSB_GET_LVB|DLM_LKSB_PUT_LVB);
+}
+
+/* messages the master site to do lock conversion
+ * locking:
+ *   caller needs:  none
+ *   taken:         takes and drops res->spinlock, uses DLM_LOCK_RES_IN_PROGRESS
+ *   held on exit:  none
+ * returns: DLM_NORMAL, DLM_RECOVERING, status from remote node
+ */
+enum dlm_status dlmconvert_remote(struct dlm_ctxt *dlm,
+                                 struct dlm_lock_resource *res,
+                                 struct dlm_lock *lock, int flags, int type)
+{
+       enum dlm_status status;
+
+       mlog(0, "type=%d, convert_type=%d, busy=%d\n", lock->ml.type,
+            lock->ml.convert_type, res->state & DLM_LOCK_RES_IN_PROGRESS);
+
+       spin_lock(&res->spinlock);
+       if (res->state & DLM_LOCK_RES_RECOVERING) {
+               mlog(0, "bailing out early since res is RECOVERING "
+                    "on secondary queue\n");
+               /* __dlm_print_one_lock_resource(res); */
+               status = DLM_RECOVERING;
+               goto bail;
+       }
+       /* will exit this call with spinlock held */
+       __dlm_wait_on_lockres(res);
+
+       if (lock->ml.convert_type != LKM_IVMODE) {
+               __dlm_print_one_lock_resource(res);
+               mlog(ML_ERROR, "converting a remote lock that is already "
+                    "converting! (cookie=%u:%llu, conv=%d)\n",
+                    dlm_get_lock_cookie_node(be64_to_cpu(lock->ml.cookie)),
+                    dlm_get_lock_cookie_seq(be64_to_cpu(lock->ml.cookie)),
+                    lock->ml.convert_type);
+               status = DLM_DENIED;
+               goto bail;
+       }
+       res->state |= DLM_LOCK_RES_IN_PROGRESS;
+       /* move lock to local convert queue */
+       /* do not alter lock refcount.  switching lists. */
+       list_move_tail(&lock->list, &res->converting);
+       lock->convert_pending = 1;
+       lock->ml.convert_type = type;
+
+       if (flags & LKM_VALBLK) {
+               if (lock->ml.type == LKM_EXMODE) {
+                       flags |= LKM_PUT_LVB;
+                       lock->lksb->flags |= DLM_LKSB_PUT_LVB;
+               } else {
+                       if (lock->ml.convert_type == LKM_NLMODE)
+                               flags &= ~LKM_VALBLK;
+                       else {
+                               flags |= LKM_GET_LVB;
+                               lock->lksb->flags |= DLM_LKSB_GET_LVB;
+                       }
+               }
+       }
+       spin_unlock(&res->spinlock);
+
+       /* no locks held here.
+        * need to wait for a reply as to whether it got queued or not. */
+       status = dlm_send_remote_convert_request(dlm, res, lock, flags, type);
+
+       spin_lock(&res->spinlock);
+       res->state &= ~DLM_LOCK_RES_IN_PROGRESS;
+       lock->convert_pending = 0;
+       /* if it failed, move it back to granted queue */
+       if (status != DLM_NORMAL) {
+               if (status != DLM_NOTQUEUED)
+                       dlm_error(status);
+               dlm_revert_pending_convert(res, lock);
+       }
+bail:
+       spin_unlock(&res->spinlock);
+
+       /* TODO: should this be a wake_one? */
+       /* wake up any IN_PROGRESS waiters */
+       wake_up(&res->wq);
+
+       return status;
+}
+
+/* sends DLM_CONVERT_LOCK_MSG to master site
+ * locking:
+ *   caller needs:  none
+ *   taken:         none
+ *   held on exit:  none
+ * returns: DLM_NOLOCKMGR, status from remote node
+ */
+static enum dlm_status dlm_send_remote_convert_request(struct dlm_ctxt *dlm,
+                                          struct dlm_lock_resource *res,
+                                          struct dlm_lock *lock, int flags, int type)
+{
+       struct dlm_convert_lock convert;
+       int tmpret;
+       enum dlm_status ret;
+       int status = 0;
+       struct kvec vec[2];
+       size_t veclen = 1;
+
+       mlog(0, "%.*s\n", res->lockname.len, res->lockname.name);
+
+       memset(&convert, 0, sizeof(struct dlm_convert_lock));
+       convert.node_idx = dlm->node_num;
+       convert.requested_type = type;
+       convert.cookie = lock->ml.cookie;
+       convert.namelen = res->lockname.len;
+       convert.flags = cpu_to_be32(flags);
+       memcpy(convert.name, res->lockname.name, convert.namelen);
+
+       vec[0].iov_len = sizeof(struct dlm_convert_lock);
+       vec[0].iov_base = &convert;
+
+       if (flags & LKM_PUT_LVB) {
+               /* extra data to send if we are updating lvb */
+               vec[1].iov_len = DLM_LVB_LEN;
+               vec[1].iov_base = lock->lksb->lvb;
+               veclen++;
+       }
+
+       tmpret = o2net_send_message_vec(DLM_CONVERT_LOCK_MSG, dlm->key,
+                                       vec, veclen, res->owner, &status);
+       if (tmpret >= 0) {
+               // successfully sent and received
+               ret = status;  // this is already a dlm_status
+               if (ret == DLM_RECOVERING) {
+                       mlog(0, "node %u returned DLM_RECOVERING from convert "
+                            "message!\n", res->owner);
+               } else if (ret == DLM_MIGRATING) {
+                       mlog(0, "node %u returned DLM_MIGRATING from convert "
+                            "message!\n", res->owner);
+               } else if (ret == DLM_FORWARD) {
+                       mlog(0, "node %u returned DLM_FORWARD from convert "
+                            "message!\n", res->owner);
+               } else if (ret != DLM_NORMAL && ret != DLM_NOTQUEUED)
+                       dlm_error(ret);
+       } else {
+               mlog(ML_ERROR, "Error %d when sending message %u (key 0x%x) to "
+                    "node %u\n", tmpret, DLM_CONVERT_LOCK_MSG, dlm->key,
+                    res->owner);
+               if (dlm_is_host_down(tmpret)) {
+                       /* instead of logging the same network error over
+                        * and over, sleep here and wait for the heartbeat
+                        * to notice the node is dead.  times out after 5s. */
+                       dlm_wait_for_node_death(dlm, res->owner,
+                                               DLM_NODE_DEATH_WAIT_MAX);
+                       ret = DLM_RECOVERING;
+                       mlog(0, "node %u died so returning DLM_RECOVERING "
+                            "from convert message!\n", res->owner);
+               } else {
+                       ret = dlm_err_to_dlm_status(tmpret);
+               }
+       }
+
+       return ret;
+}
+
+/* handler for DLM_CONVERT_LOCK_MSG on master site
+ * locking:
+ *   caller needs:  none
+ *   taken:         takes and drop res->spinlock
+ *   held on exit:  none
+ * returns: DLM_NORMAL, DLM_IVLOCKID, DLM_BADARGS,
+ *          status from __dlmconvert_master
+ */
+int dlm_convert_lock_handler(struct o2net_msg *msg, u32 len, void *data,
+                            void **ret_data)
+{
+       struct dlm_ctxt *dlm = data;
+       struct dlm_convert_lock *cnv = (struct dlm_convert_lock *)msg->buf;
+       struct dlm_lock_resource *res = NULL;
+       struct dlm_lock *lock = NULL;
+       struct dlm_lock *tmp_lock;
+       struct dlm_lockstatus *lksb;
+       enum dlm_status status = DLM_NORMAL;
+       u32 flags;
+       int call_ast = 0, kick_thread = 0, ast_reserved = 0, wake = 0;
+
+       if (!dlm_grab(dlm)) {
+               dlm_error(DLM_REJECTED);
+               return DLM_REJECTED;
+       }
+
+       mlog_bug_on_msg(!dlm_domain_fully_joined(dlm),
+                       "Domain %s not fully joined!\n", dlm->name);
+
+       if (cnv->namelen > DLM_LOCKID_NAME_MAX) {
+               status = DLM_IVBUFLEN;
+               dlm_error(status);
+               goto leave;
+       }
+
+       flags = be32_to_cpu(cnv->flags);
+
+       if ((flags & (LKM_PUT_LVB|LKM_GET_LVB)) ==
+            (LKM_PUT_LVB|LKM_GET_LVB)) {
+               mlog(ML_ERROR, "both PUT and GET lvb specified\n");
+               status = DLM_BADARGS;
+               goto leave;
+       }
+
+       mlog(0, "lvb: %s\n", flags & LKM_PUT_LVB ? "put lvb" :
+            (flags & LKM_GET_LVB ? "get lvb" : "none"));
+
+       status = DLM_IVLOCKID;
+       res = dlm_lookup_lockres(dlm, cnv->name, cnv->namelen);
+       if (!res) {
+               dlm_error(status);
+               goto leave;
+       }
+
+       spin_lock(&res->spinlock);
+       status = __dlm_lockres_state_to_status(res);
+       if (status != DLM_NORMAL) {
+               spin_unlock(&res->spinlock);
+               dlm_error(status);
+               goto leave;
+       }
+       list_for_each_entry(tmp_lock, &res->granted, list) {
+               if (tmp_lock->ml.cookie == cnv->cookie &&
+                   tmp_lock->ml.node == cnv->node_idx) {
+                       lock = tmp_lock;
+                       dlm_lock_get(lock);
+                       break;
+               }
+       }
+       spin_unlock(&res->spinlock);
+       if (!lock) {
+               status = DLM_IVLOCKID;
+               mlog(ML_ERROR, "did not find lock to convert on grant queue! "
+                              "cookie=%u:%llu\n",
+                    dlm_get_lock_cookie_node(be64_to_cpu(cnv->cookie)),
+                    dlm_get_lock_cookie_seq(be64_to_cpu(cnv->cookie)));
+               dlm_print_one_lock_resource(res);
+               goto leave;
+       }
+
+       /* found the lock */
+       lksb = lock->lksb;
+
+       /* see if caller needed to get/put lvb */
+       if (flags & LKM_PUT_LVB) {
+               BUG_ON(lksb->flags & (DLM_LKSB_PUT_LVB|DLM_LKSB_GET_LVB));
+               lksb->flags |= DLM_LKSB_PUT_LVB;
+               memcpy(&lksb->lvb[0], &cnv->lvb[0], DLM_LVB_LEN);
+       } else if (flags & LKM_GET_LVB) {
+               BUG_ON(lksb->flags & (DLM_LKSB_PUT_LVB|DLM_LKSB_GET_LVB));
+               lksb->flags |= DLM_LKSB_GET_LVB;
+       }
+
+       spin_lock(&res->spinlock);
+       status = __dlm_lockres_state_to_status(res);
+       if (status == DLM_NORMAL) {
+               __dlm_lockres_reserve_ast(res);
+               ast_reserved = 1;
+               res->state |= DLM_LOCK_RES_IN_PROGRESS;
+               status = __dlmconvert_master(dlm, res, lock, flags,
+                                            cnv->requested_type,
+                                            &call_ast, &kick_thread);
+               res->state &= ~DLM_LOCK_RES_IN_PROGRESS;
+               wake = 1;
+       }
+       spin_unlock(&res->spinlock);
+       if (wake)
+               wake_up(&res->wq);
+
+       if (status != DLM_NORMAL) {
+               if (status != DLM_NOTQUEUED)
+                       dlm_error(status);
+               lksb->flags &= ~(DLM_LKSB_GET_LVB|DLM_LKSB_PUT_LVB);
+       }
+
+leave:
+       if (lock)
+               dlm_lock_put(lock);
+
+       /* either queue the ast or release it, if reserved */
+       if (call_ast)
+               dlm_queue_ast(dlm, lock);
+       else if (ast_reserved)
+               dlm_lockres_release_ast(dlm, res);
+
+       if (kick_thread)
+               dlm_kick_thread(dlm, res);
+
+       if (res)
+               dlm_lockres_put(res);
+
+       dlm_put(dlm);
+
+       return status;
+}