Remove redundant parameter fd from SMB_VFS_FTRUNCATE().
[ira/wip.git] / source3 / smbd / blocking.c
index 27a51839529a37139de7025c165d94e923411120..4e0d5289f88e78ae3c0cd0e8f9d08995bb3cbcda 100644 (file)
@@ -1,12 +1,11 @@
 /* 
-   Unix SMB/Netbios implementation.
-   Version 1.9.
+   Unix SMB/CIFS implementation.
    Blocking Locking functions
-   Copyright (C) Jeremy Allison 1998
+   Copyright (C) Jeremy Allison 1998-2003
    
    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
+   the Free Software Foundation; either version 3 of the License, or
    (at your option) any later version.
    
    This program is distributed in the hope that it will be useful,
    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., 675 Mass Ave, Cambridge, MA 02139, USA.
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
 #include "includes.h"
-extern int DEBUGLEVEL;
-extern int Client;
-extern int chain_size;
-extern char *OutBuffer;
+#undef DBGC_CLASS
+#define DBGC_CLASS DBGC_LOCKING
 
 /****************************************************************************
  This is the structure to queue to implement blocking locks.
  notify. It consists of the requesting SMB and the expiry time.
 *****************************************************************************/
 
-typedef struct {
-  ubi_slNode msg_next;
-  int com_type;
-  files_struct *fsp;
-  time_t expire_time;
-  int lock_num;
-  char *inbuf;
-  int length;
+typedef struct _blocking_lock_record {
+       struct _blocking_lock_record *next;
+       struct _blocking_lock_record *prev;
+       int com_type;
+       files_struct *fsp;
+       struct timeval expire_time;
+       int lock_num;
+       SMB_BIG_UINT offset;
+       SMB_BIG_UINT count;
+       uint32 lock_pid;
+       uint32 blocking_pid; /* PID that blocks us. */
+       enum brl_flavour lock_flav;
+       enum brl_type lock_type;
+       char *inbuf;
+       int length;
+       bool encrypted;
 } blocking_lock_record;
 
-static ubi_slList blocking_lock_queue = { NULL, (ubi_slNodePtr)&blocking_lock_queue, 0};
+/* dlink list we store pending lock records on. */
+static blocking_lock_record *blocking_lock_queue;
+
+/* dlink list we move cancelled lock records onto. */
+static blocking_lock_record *blocking_lock_cancelled_queue;
+
+/* The event that makes us process our blocking lock queue */
+static struct timed_event *brl_timeout;
 
 /****************************************************************************
  Destructor for the above structure.
@@ -48,94 +59,195 @@ static ubi_slList blocking_lock_queue = { NULL, (ubi_slNodePtr)&blocking_lock_qu
 
 static void free_blocking_lock_record(blocking_lock_record *blr)
 {
-  free(blr->inbuf);
-  free((char *)blr);
-}
-
-/****************************************************************************
- Get the files_struct given a particular queued SMB.
-*****************************************************************************/
-
-static files_struct *get_fsp_from_pkt(char *inbuf)
-{
-  switch(CVAL(inbuf,smb_com)) {
-  case SMBlock:
-  case SMBlockread:
-    return file_fsp(inbuf,smb_vwv0);
-  case SMBlockingX:
-    return file_fsp(inbuf,smb_vwv2);
-  default:
-    DEBUG(0,("get_fsp_from_pkt: PANIC - unknown type on blocking lock queue - exiting.!\n"));
-    exit_server("PANIC - unknown type on blocking lock queue");
-  }
-  return NULL; /* Keep compiler happy. */
+       SAFE_FREE(blr->inbuf);
+       SAFE_FREE(blr);
 }
 
 /****************************************************************************
  Determine if this is a secondary element of a chained SMB.
   **************************************************************************/
 
-static BOOL in_chained_smb(void)
+static bool in_chained_smb(void)
 {
-  return (chain_size != 0);
+       return (chain_size != 0);
 }
 
-/****************************************************************************
- Function to push a blocking lock request onto the lock queue.
-****************************************************************************/
-
-BOOL push_blocking_lock_request( char *inbuf, int length, int lock_timeout, int lock_num)
+static void received_unlock_msg(struct messaging_context *msg,
+                               void *private_data,
+                               uint32_t msg_type,
+                               struct server_id server_id,
+                               DATA_BLOB *data);
+static void process_blocking_lock_queue(void);
+
+static void brl_timeout_fn(struct event_context *event_ctx,
+                          struct timed_event *te,
+                          const struct timeval *now,
+                          void *private_data)
 {
-  blocking_lock_record *blr;
-
-  if(in_chained_smb() ) {
-    DEBUG(0,("push_blocking_lock_request: cannot queue a chained request (currently).\n"));
-    return False;
-  }
-
-  /*
-   * Now queue an entry on the blocking lock queue. We setup
-   * the expiration time here.
-   */
+       SMB_ASSERT(brl_timeout == te);
+       TALLOC_FREE(brl_timeout);
 
-  if((blr = (blocking_lock_record *)malloc(sizeof(blocking_lock_record))) == NULL) {
-    DEBUG(0,("push_blocking_lock_request: Malloc fail !\n" ));
-    return False;
-  }
-
-  if((blr->inbuf = (char *)malloc(length)) == NULL) {
-    DEBUG(0,("push_blocking_lock_request: Malloc fail (2)!\n" ));
-    free((char *)blr);
-    return False;
-  }
-
-  blr->com_type = CVAL(inbuf,smb_com);
-  blr->fsp = get_fsp_from_pkt(inbuf);
-  blr->expire_time = (lock_timeout == -1) ? (time_t)-1 : time(NULL) + (time_t)lock_timeout;
-  blr->lock_num = lock_num;
-  memcpy(blr->inbuf, inbuf, length);
-  blr->length = length;
-
-  ubi_slAddTail(&blocking_lock_queue, blr);
+       change_to_root_user();  /* TODO: Possibly run all timed events as
+                                * root */
 
+       process_blocking_lock_queue();
+}
 
-  DEBUG(3,("push_blocking_lock_request: lock request length=%d blocked with expiry time %d \
-for fnum = %d, name = %s\n", length, (int)blr->expire_time, 
-        blr->fsp->fnum, blr->fsp->fsp_name ));
+/****************************************************************************
+ After a change to blocking_lock_queue, recalculate the timed_event for the
+ next processing.
+****************************************************************************/
 
-  return True;
+static bool recalc_brl_timeout(void)
+{
+       blocking_lock_record *brl;
+       struct timeval next_timeout;
+
+       TALLOC_FREE(brl_timeout);
+
+       next_timeout = timeval_zero();  
+
+       for (brl = blocking_lock_queue; brl; brl = brl->next) {
+               if (timeval_is_zero(&brl->expire_time)) {
+                       /*
+                        * If we're blocked on pid 0xFFFFFFFF this is
+                        * a POSIX lock, so calculate a timeout of
+                        * 10 seconds into the future.
+                        */
+                        if (brl->blocking_pid == 0xFFFFFFFF) {
+                               struct timeval psx_to = timeval_current_ofs(10, 0);
+                               next_timeout = timeval_min(&next_timeout, &psx_to);
+                        }
+
+                       continue;
+               }
+
+               if (timeval_is_zero(&next_timeout)) {
+                       next_timeout = brl->expire_time;
+               }
+               else {
+                       next_timeout = timeval_min(&next_timeout,
+                                                  &brl->expire_time);
+               }
+       }
+
+       if (timeval_is_zero(&next_timeout)) {
+               return True;
+       }
+
+       if (!(brl_timeout = event_add_timed(smbd_event_context(), NULL,
+                                           next_timeout, "brl_timeout",
+                                           brl_timeout_fn, NULL))) {
+               return False;
+       }
+
+       return True;
 }
 
+
 /****************************************************************************
Return a smd with a given size.
-*****************************************************************************/
Function to push a blocking lock request onto the lock queue.
+****************************************************************************/
 
-static void send_blocking_reply(char *outbuf, int outsize)
+bool push_blocking_lock_request( struct byte_range_lock *br_lck,
+               const struct smb_request *req,
+               files_struct *fsp,
+               int lock_timeout,
+               int lock_num,
+               uint32 lock_pid,
+               enum brl_type lock_type,
+               enum brl_flavour lock_flav,
+               SMB_BIG_UINT offset,
+               SMB_BIG_UINT count,
+               uint32 blocking_pid)
 {
-  if(outsize > 4)
-    smb_setlen(outbuf,outsize - 4);
-
-  send_smb(Client,outbuf);
+       static bool set_lock_msg;
+       size_t length = smb_len(req->inbuf)+4;
+       blocking_lock_record *blr;
+       NTSTATUS status;
+
+       if(in_chained_smb() ) {
+               DEBUG(0,("push_blocking_lock_request: cannot queue a chained request (currently).\n"));
+               return False;
+       }
+
+       /*
+        * Now queue an entry on the blocking lock queue. We setup
+        * the expiration time here.
+        */
+
+       if((blr = SMB_MALLOC_P(blocking_lock_record)) == NULL) {
+               DEBUG(0,("push_blocking_lock_request: Malloc fail !\n" ));
+               return False;
+       }
+
+       blr->next = NULL;
+       blr->prev = NULL;
+
+       if((blr->inbuf = (char *)SMB_MALLOC(length)) == NULL) {
+               DEBUG(0,("push_blocking_lock_request: Malloc fail (2)!\n" ));
+               SAFE_FREE(blr);
+               return False;
+       }
+
+       blr->com_type = CVAL(req->inbuf,smb_com);
+       blr->fsp = fsp;
+       if (lock_timeout == -1) {
+               blr->expire_time.tv_sec = 0;
+               blr->expire_time.tv_usec = 0; /* Never expire. */
+       } else {
+               blr->expire_time = timeval_current_ofs(lock_timeout/1000,
+                                       (lock_timeout % 1000) * 1000);
+       }
+       blr->lock_num = lock_num;
+       blr->lock_pid = lock_pid;
+       blr->blocking_pid = blocking_pid;
+       blr->lock_flav = lock_flav;
+       blr->lock_type = lock_type;
+       blr->offset = offset;
+       blr->count = count;
+       memcpy(blr->inbuf, req->inbuf, length);
+       blr->length = length;
+       blr->encrypted = req->encrypted;
+
+       /* Add a pending lock record for this. */
+       status = brl_lock(smbd_messaging_context(), br_lck,
+                       lock_pid,
+                       procid_self(),
+                       offset,
+                       count,
+                       lock_type == READ_LOCK ? PENDING_READ_LOCK : PENDING_WRITE_LOCK,
+                       blr->lock_flav,
+                       lock_timeout ? True : False, /* blocking_lock. */
+                       NULL);
+
+       if (!NT_STATUS_IS_OK(status)) {
+               DEBUG(0,("push_blocking_lock_request: failed to add PENDING_LOCK record.\n"));
+               DLIST_REMOVE(blocking_lock_queue, blr);
+               free_blocking_lock_record(blr);
+               return False;
+       }
+
+       DLIST_ADD_END(blocking_lock_queue, blr, blocking_lock_record *);
+       recalc_brl_timeout();
+
+       /* Ensure we'll receive messages when this is unlocked. */
+       if (!set_lock_msg) {
+               messaging_register(smbd_messaging_context(), NULL,
+                                  MSG_SMB_UNLOCK, received_unlock_msg);
+               set_lock_msg = True;
+       }
+
+       DEBUG(3,("push_blocking_lock_request: lock request length=%u blocked with "
+               "expiry time (%u sec. %u usec) (+%d msec) for fnum = %d, name = %s\n",
+               (unsigned int)length, (unsigned int)blr->expire_time.tv_sec,
+               (unsigned int)blr->expire_time.tv_usec, lock_timeout,
+               blr->fsp->fnum, blr->fsp->fsp_name ));
+
+       /* Push the MID of this packet on the signing queue. */
+       srv_defer_sign_response(SVAL(req->inbuf,smb_mid));
+
+       return True;
 }
 
 /****************************************************************************
@@ -144,44 +256,69 @@ static void send_blocking_reply(char *outbuf, int outsize)
 
 static void reply_lockingX_success(blocking_lock_record *blr)
 {
-  char *outbuf = OutBuffer;
-  int bufsize = BUFFER_SIZE;
-  char *inbuf = blr->inbuf;
-  int outsize = 0;
-
-  construct_reply_common(inbuf, outbuf);
-  set_message(outbuf,2,0,True);
-
-  /*
-   * As this message is a lockingX call we must handle
-   * any following chained message correctly.
-   * This is normally handled in construct_reply(),
-   * but as that calls switch_message, we can't use
-   * that here and must set up the chain info manually.
-   */
-
-  outsize = chain_reply(inbuf,outbuf,blr->length,bufsize);
-
-  outsize += chain_size;
-
-  send_blocking_reply(outbuf,outsize);
+       struct smb_request *req;
+
+       if (!(req = talloc(talloc_tos(), struct smb_request))) {
+               smb_panic("Could not allocate smb_request");
+       }
+
+       init_smb_request(req, (uint8 *)blr->inbuf, 0, blr->encrypted);
+       reply_outbuf(req, 2, 0);
+
+       /*
+        * As this message is a lockingX call we must handle
+        * any following chained message correctly.
+        * This is normally handled in construct_reply(),
+        * but as that calls switch_message, we can't use
+        * that here and must set up the chain info manually.
+        */
+
+       chain_reply(req);
+
+       if (!srv_send_smb(smbd_server_fd(),
+                       (char *)req->outbuf,
+                       IS_CONN_ENCRYPTED(blr->fsp->conn))) {
+               exit_server_cleanly("send_blocking_reply: srv_send_smb failed.");
+       }
 }
 
 /****************************************************************************
  Return a generic lock fail error blocking call.
 *****************************************************************************/
 
-static void generic_blocking_lock_error(blocking_lock_record *blr, int eclass, int32 ecode)
+static void generic_blocking_lock_error(blocking_lock_record *blr, NTSTATUS status)
 {
-  char *outbuf = OutBuffer;
-  char *inbuf = blr->inbuf;
-  construct_reply_common(inbuf, outbuf);
-
-  if(eclass == 0) /* NT Error. */
-    SSVAL(outbuf,smb_flg2, SVAL(outbuf,smb_flg2) | FLAGS2_32_BIT_ERROR_CODES);
-
-  ERROR(eclass,ecode);
-  send_smb(Client,outbuf);
+       char outbuf[smb_size];
+       char *inbuf = blr->inbuf;
+
+       construct_reply_common(inbuf, outbuf);
+
+       /* whenever a timeout is given w2k maps LOCK_NOT_GRANTED to
+          FILE_LOCK_CONFLICT! (tridge) */
+       if (NT_STATUS_EQUAL(status, NT_STATUS_LOCK_NOT_GRANTED)) {
+               status = NT_STATUS_FILE_LOCK_CONFLICT;
+       }
+
+       if (NT_STATUS_EQUAL(status, NT_STATUS_FILE_LOCK_CONFLICT)) {
+               /* Store the last lock error. */
+               files_struct *fsp = blr->fsp;
+
+               if (fsp) {
+                       fsp->last_lock_failure.context.smbpid = blr->lock_pid;
+                       fsp->last_lock_failure.context.tid = fsp->conn->cnum;
+                       fsp->last_lock_failure.context.pid = procid_self();
+                       fsp->last_lock_failure.start = blr->offset;
+                       fsp->last_lock_failure.size = blr->count;
+                       fsp->last_lock_failure.fnum = fsp->fnum;
+                       fsp->last_lock_failure.lock_type = READ_LOCK; /* Don't care. */
+                       fsp->last_lock_failure.lock_flav = blr->lock_flav;
+               }
+       }
+
+       ERROR_NT(status);
+       if (!srv_send_smb(smbd_server_fd(),outbuf, blr->encrypted)) {
+               exit_server_cleanly("generic_blocking_lock_error: srv_send_smb failed.");
+       }
 }
 
 /****************************************************************************
@@ -189,436 +326,606 @@ static void generic_blocking_lock_error(blocking_lock_record *blr, int eclass, i
  obtained first.
 *****************************************************************************/
 
-static void reply_lockingX_error(blocking_lock_record *blr, int eclass, int32 ecode)
+static void reply_lockingX_error(blocking_lock_record *blr, NTSTATUS status)
 {
-  char *inbuf = blr->inbuf;
-  files_struct *fsp = blr->fsp;
-  connection_struct *conn = conn_find(SVAL(inbuf,smb_tid));
-  uint16 num_ulocks = SVAL(inbuf,smb_vwv6);
-  SMB_OFF_T count, offset;
-  unsigned char locktype = CVAL(inbuf,smb_vwv3);
-  BOOL large_file_format = (locktype & LOCKING_ANDX_LARGE_FILES);
-  char *data;
-  int i;
-
-  data = smb_buf(inbuf) + ((large_file_format ? 20 : 10)*num_ulocks);
-
-  /* 
-   * Data now points at the beginning of the list
-   * of smb_lkrng structs.
-   */
-
-  for(i = blr->lock_num; i >= 0; i--) {
-    int dummy1;
-    uint32 dummy2;
-    if(!large_file_format) {
-      count = IVAL(data,SMB_LKLEN_OFFSET(i));
-      offset = IVAL(data,SMB_LKOFF_OFFSET(i));
-    }
-#ifdef LARGE_SMB_OFF_T
-    else {
-      count = (((SMB_OFF_T) IVAL(data,SMB_LARGE_LKLEN_OFFSET_HIGH(i))) << 32) |
-              ((SMB_OFF_T) IVAL(data,SMB_LARGE_LKLEN_OFFSET_LOW(i)));
-      offset = (((SMB_OFF_T) IVAL(data,SMB_LARGE_LKOFF_OFFSET_HIGH(i))) << 32) |
-               ((SMB_OFF_T) IVAL(data,SMB_LARGE_LKOFF_OFFSET_LOW(i)));
-    }
-#endif /* LARGE_SMB_OFF_T */
-    do_unlock(fsp,conn,count,offset,&dummy1,&dummy2);
-  }
-
-  generic_blocking_lock_error(blr, eclass, ecode);
+       char *inbuf = blr->inbuf;
+       files_struct *fsp = blr->fsp;
+       uint16 num_ulocks = SVAL(inbuf,smb_vwv6);
+       SMB_BIG_UINT count = (SMB_BIG_UINT)0, offset = (SMB_BIG_UINT) 0;
+       uint32 lock_pid;
+       unsigned char locktype = CVAL(inbuf,smb_vwv3);
+       bool large_file_format = (locktype & LOCKING_ANDX_LARGE_FILES);
+       char *data;
+       int i;
+
+       data = smb_buf(inbuf) + ((large_file_format ? 20 : 10)*num_ulocks);
+       
+       /* 
+        * Data now points at the beginning of the list
+        * of smb_lkrng structs.
+        */
+
+       /*
+        * Ensure we don't do a remove on the lock that just failed,
+        * as under POSIX rules, if we have a lock already there, we
+        * will delete it (and we shouldn't) .....
+        */
+       
+       for(i = blr->lock_num - 1; i >= 0; i--) {
+               bool err;
+               
+               lock_pid = get_lock_pid( data, i, large_file_format);
+               count = get_lock_count( data, i, large_file_format);
+               offset = get_lock_offset( data, i, large_file_format, &err);
+               
+               /*
+                * We know err cannot be set as if it was the lock
+                * request would never have been queued. JRA.
+                */
+               
+               do_unlock(smbd_messaging_context(),
+                       fsp,
+                       lock_pid,
+                       count,
+                       offset,
+                       WINDOWS_LOCK);
+       }
+       
+       generic_blocking_lock_error(blr, status);
 }
 
 /****************************************************************************
  Return a lock fail error.
 *****************************************************************************/
 
-static void blocking_lock_reply_error(blocking_lock_record *blr, int eclass, int32 ecode)
+static void blocking_lock_reply_error(blocking_lock_record *blr, NTSTATUS status)
 {
-  switch(blr->com_type) {
-  case SMBlock:
-    generic_blocking_lock_error(blr, eclass, ecode);
-    break;
-  case SMBlockread:
-    generic_blocking_lock_error(blr, eclass, ecode);
-    break;
-  case SMBlockingX:
-    reply_lockingX_error(blr, eclass, ecode);
-    break;
-  default:
-    DEBUG(0,("blocking_lock_reply_error: PANIC - unknown type on blocking lock queue - exiting.!\n"));
-    exit_server("PANIC - unknown type on blocking lock queue");
-  }
+       switch(blr->com_type) {
+       case SMBlockingX:
+               reply_lockingX_error(blr, status);
+               break;
+       case SMBtrans2:
+       case SMBtranss2:
+               {
+                       char outbuf[smb_size];
+                       char *inbuf = blr->inbuf;
+                       construct_reply_common(inbuf, outbuf);
+                       /* construct_reply_common has done us the favor to pre-fill the
+                        * command field with SMBtranss2 which is wrong :-)
+                        */
+                       SCVAL(outbuf,smb_com,SMBtrans2);
+                       ERROR_NT(status);
+                       if (!srv_send_smb(smbd_server_fd(),
+                                       outbuf,
+                                       IS_CONN_ENCRYPTED(blr->fsp->conn))) {
+                               exit_server_cleanly("blocking_lock_reply_error: srv_send_smb failed.");
+                       }
+                       break;
+               }
+       default:
+               DEBUG(0,("blocking_lock_reply_error: PANIC - unknown type on blocking lock queue - exiting.!\n"));
+               exit_server("PANIC - unknown type on blocking lock queue");
+       }
 }
 
 /****************************************************************************
- Attempt to finish off getting all pending blocking locks for a lockread call.
+ Attempt to finish off getting all pending blocking locks for a lockingX call.
  Returns True if we want to be removed from the list.
 *****************************************************************************/
 
-static BOOL process_lockread(blocking_lock_record *blr)
+static bool process_lockingX(blocking_lock_record *blr)
 {
-  char *outbuf = OutBuffer;
-  char *inbuf = blr->inbuf;
-  ssize_t nread = -1;
-  char *data;
-  int outsize = 0;
-  SMB_OFF_T startpos;
-  size_t numtoread;
-  int eclass;
-  uint32 ecode;
-  connection_struct *conn = conn_find(SVAL(inbuf,smb_tid));
-  files_struct *fsp = blr->fsp;
-
-  numtoread = SVAL(inbuf,smb_vwv1);
-  startpos = IVAL(inbuf,smb_vwv2);
-  numtoread = MIN(BUFFER_SIZE-outsize,numtoread);
-  data = smb_buf(outbuf) + 3;
-  if(!do_lock( fsp, conn, numtoread, startpos, F_RDLCK, &eclass, &ecode)) {
-    if((errno != EACCES) && (errno != EAGAIN)) {
-      /*
-       * We have other than a "can't get lock" POSIX
-       * error. Send an error.
-       * Return True so we get dequeued.
-       */
-
-      generic_blocking_lock_error(blr, eclass, ecode);
-      return True;
-    }
-
-    /*
-     * Still waiting for lock....
-     */
-
-    DEBUG(10,("process_lockread: failed to get lock for file = %s. Still waiting....\n",
-          fsp->fsp_name));
-    return False;
-  }
-
-  nread = read_file(fsp,data,startpos,numtoread);
-
-  if (nread < 0) {
-    generic_blocking_lock_error(blr,ERRDOS,ERRnoaccess);
-    return True;
-  }
-
-  construct_reply_common(inbuf, outbuf);
-  outsize = set_message(outbuf,5,3,True);
-
-  outsize += nread;
-  SSVAL(outbuf,smb_vwv0,nread);
-  SSVAL(outbuf,smb_vwv5,nread+3);
-  SSVAL(smb_buf(outbuf),1,nread);
-
-  DEBUG(3, ( "process_lockread file = %s, fnum=%d num=%d nread=%d\n",
-        fsp->fsp_name, fsp->fnum, numtoread, nread ) );
-
-  send_blocking_reply(outbuf,outsize);
-  return True;
+       char *inbuf = blr->inbuf;
+       unsigned char locktype = CVAL(inbuf,smb_vwv3);
+       files_struct *fsp = blr->fsp;
+       uint16 num_ulocks = SVAL(inbuf,smb_vwv6);
+       uint16 num_locks = SVAL(inbuf,smb_vwv7);
+       SMB_BIG_UINT count = (SMB_BIG_UINT)0, offset = (SMB_BIG_UINT)0;
+       uint32 lock_pid;
+       bool large_file_format = (locktype & LOCKING_ANDX_LARGE_FILES);
+       char *data;
+       NTSTATUS status = NT_STATUS_OK;
+
+       data = smb_buf(inbuf) + ((large_file_format ? 20 : 10)*num_ulocks);
+
+       /* 
+        * Data now points at the beginning of the list
+        * of smb_lkrng structs.
+        */
+
+       for(; blr->lock_num < num_locks; blr->lock_num++) {
+               struct byte_range_lock *br_lck = NULL;
+               bool err;
+
+               lock_pid = get_lock_pid( data, blr->lock_num, large_file_format);
+               count = get_lock_count( data, blr->lock_num, large_file_format);
+               offset = get_lock_offset( data, blr->lock_num, large_file_format, &err);
+               
+               /*
+                * We know err cannot be set as if it was the lock
+                * request would never have been queued. JRA.
+                */
+               errno = 0;
+               br_lck = do_lock(smbd_messaging_context(),
+                               fsp,
+                               lock_pid,
+                               count,
+                               offset, 
+                               ((locktype & LOCKING_ANDX_SHARED_LOCK) ?
+                                       READ_LOCK : WRITE_LOCK),
+                               WINDOWS_LOCK,
+                               True,
+                               &status,
+                               &blr->blocking_pid);
+
+               TALLOC_FREE(br_lck);
+
+               if (NT_STATUS_IS_ERR(status)) {
+                       break;
+               }
+       }
+
+       if(blr->lock_num == num_locks) {
+               /*
+                * Success - we got all the locks.
+                */
+               
+               DEBUG(3,("process_lockingX file = %s, fnum=%d type=%d num_locks=%d\n",
+                        fsp->fsp_name, fsp->fnum, (unsigned int)locktype, num_locks) );
+
+               reply_lockingX_success(blr);
+               return True;
+       } else if (!NT_STATUS_EQUAL(status,NT_STATUS_LOCK_NOT_GRANTED) &&
+                       !NT_STATUS_EQUAL(status,NT_STATUS_FILE_LOCK_CONFLICT)) {
+                       /*
+                        * We have other than a "can't get lock"
+                        * error. Free any locks we had and return an error.
+                        * Return True so we get dequeued.
+                        */
+               
+               blocking_lock_reply_error(blr, status);
+               return True;
+       }
+
+       /*
+        * Still can't get all the locks - keep waiting.
+        */
+       
+       DEBUG(10,("process_lockingX: only got %d locks of %d needed for file %s, fnum = %d. \
+Waiting....\n", 
+                 blr->lock_num, num_locks, fsp->fsp_name, fsp->fnum));
+       
+       return False;
 }
 
 /****************************************************************************
- Attempt to finish off getting all pending blocking locks for a lock call.
+ Attempt to get the posix lock request from a SMBtrans2 call.
  Returns True if we want to be removed from the list.
 *****************************************************************************/
 
-static BOOL process_lock(blocking_lock_record *blr)
+static bool process_trans2(blocking_lock_record *blr)
 {
-  char *outbuf = OutBuffer;
-  char *inbuf = blr->inbuf;
-  int outsize;
-  SMB_OFF_T count,offset;
-  int eclass;
-  uint32 ecode;
-  connection_struct *conn = conn_find(SVAL(inbuf,smb_tid));
-  files_struct *fsp = blr->fsp;
-
-  count = IVAL(inbuf,smb_vwv1);
-  offset = IVAL(inbuf,smb_vwv3);
-
-  errno = 0;
-  if (!do_lock(fsp, conn, count, offset, F_WRLCK, &eclass, &ecode)) {
-    if((errno != EACCES) && (errno != EAGAIN)) {
-
-      /*
-       * We have other than a "can't get lock" POSIX
-       * error. Send an error.
-       * Return True so we get dequeued.
-       */
-
-      blocking_lock_reply_error(blr, eclass, ecode);
-      return True;
-    }
-
-    /*
-     * Still can't get the lock - keep waiting.
-     */
-
-    DEBUG(10,("process_lock: failed to get lock for file = %s. Still waiting....\n",
-          fsp->fsp_name));
-    return False;
-  }
-
-  /*
-   * Success - we got the lock.
-   */
-
-  DEBUG(3,("process_lock : file=%s fnum=%d offset=%.0f count=%.0f\n",
-       fsp->fsp_name, fsp->fnum, (double)offset, (double)count));
-
-  construct_reply_common(inbuf, outbuf);
-  outsize = set_message(outbuf,0,0,True);
-  send_blocking_reply(outbuf,outsize);
-  return True;
+       struct smb_request *req;
+       char params[2];
+       NTSTATUS status;
+       struct byte_range_lock *br_lck = do_lock(smbd_messaging_context(),
+                                               blr->fsp,
+                                               blr->lock_pid,
+                                               blr->count,
+                                               blr->offset,
+                                               blr->lock_type,
+                                               blr->lock_flav,
+                                               True,
+                                               &status,
+                                               &blr->blocking_pid);
+       TALLOC_FREE(br_lck);
+
+       if (!NT_STATUS_IS_OK(status)) {
+               if (ERROR_WAS_LOCK_DENIED(status)) {
+                       /* Still can't get the lock, just keep waiting. */
+                       return False;
+               }       
+               /*
+                * We have other than a "can't get lock"
+                * error. Send an error and return True so we get dequeued.
+                */
+               blocking_lock_reply_error(blr, status);
+               return True;
+       }
+
+       /* We finally got the lock, return success. */
+
+       if (!(req = talloc(talloc_tos(), struct smb_request))) {
+               blocking_lock_reply_error(blr, NT_STATUS_NO_MEMORY);
+               return True;
+       }
+
+       init_smb_request(req, (uint8 *)blr->inbuf, 0, blr->encrypted);
+
+       SCVAL(req->inbuf, smb_com, SMBtrans2);
+       SSVAL(params,0,0);
+       /* Fake up max_data_bytes here - we know it fits. */
+       send_trans2_replies(blr->fsp->conn, req, params, 2, NULL, 0, 0xffff);
+       return True;
 }
 
+
 /****************************************************************************
Attempt to finish off getting all pending blocking locks for a lockingX call.
Process a blocking lock SMB.
  Returns True if we want to be removed from the list.
 *****************************************************************************/
 
-static BOOL process_lockingX(blocking_lock_record *blr)
+static bool blocking_lock_record_process(blocking_lock_record *blr)
 {
-  char *inbuf = blr->inbuf;
-  unsigned char locktype = CVAL(inbuf,smb_vwv3);
-  files_struct *fsp = blr->fsp;
-  connection_struct *conn = conn_find(SVAL(inbuf,smb_tid));
-  uint16 num_ulocks = SVAL(inbuf,smb_vwv6);
-  uint16 num_locks = SVAL(inbuf,smb_vwv7);
-  SMB_OFF_T count, offset;
-  BOOL large_file_format = (locktype & LOCKING_ANDX_LARGE_FILES);
-  char *data;
-  int eclass=0;
-  uint32 ecode=0;
-
-  data = smb_buf(inbuf) + ((large_file_format ? 20 : 10)*num_ulocks);
-
-  /* 
-   * Data now points at the beginning of the list
-   * of smb_lkrng structs.
-   */
-
-  for(; blr->lock_num < num_locks; blr->lock_num++) {
-    if(!large_file_format) {
-      count = IVAL(data,SMB_LKLEN_OFFSET(blr->lock_num));
-      offset = IVAL(data,SMB_LKOFF_OFFSET(blr->lock_num));
-    }
-#ifdef LARGE_SMB_OFF_T
-    else {
-      count = (((SMB_OFF_T) IVAL(data,SMB_LARGE_LKLEN_OFFSET_HIGH(blr->lock_num))) << 32) |
-              ((SMB_OFF_T) IVAL(data,SMB_LARGE_LKLEN_OFFSET_LOW(blr->lock_num)));
-      offset = (((SMB_OFF_T) IVAL(data,SMB_LARGE_LKOFF_OFFSET_HIGH(blr->lock_num))) << 32) |
-               ((SMB_OFF_T) IVAL(data,SMB_LARGE_LKOFF_OFFSET_LOW(blr->lock_num)));
-    }
-#endif /* LARGE_SMB_OFF_T */
-    errno = 0;
-    if(!do_lock(fsp,conn,count,offset, ((locktype & 1) ? F_RDLCK : F_WRLCK),
-                &eclass, &ecode))
-      break;
-  }
-
-  if(blr->lock_num == num_locks) {
-
-    /*
-     * Success - we got all the locks.
-     */
-
-    DEBUG(3,("process_lockingX file = %s, fnum=%d type=%d num_locks=%d\n",
-          fsp->fsp_name, fsp->fnum, (unsigned int)locktype, num_locks) );
-
-    reply_lockingX_success(blr);
-    return True;
-
-  } else if((errno != EACCES) && (errno != EAGAIN)) {
-
-    /*
-     * We have other than a "can't get lock" POSIX
-     * error. Free any locks we had and return an error.
-     * Return True so we get dequeued.
-     */
-
-    blocking_lock_reply_error(blr, eclass, ecode);
-    return True;
-  }
-
-  /*
-   * Still can't get all the locks - keep waiting.
-   */
-
-  DEBUG(10,("process_lockingX: only got %d locks of %d needed for file %s, fnum = %d. \
-Waiting....\n", blr->lock_num, num_locks, fsp->fsp_name, fsp->fnum));
-
-  return False;
+       switch(blr->com_type) {
+               case SMBlockingX:
+                       return process_lockingX(blr);
+               case SMBtrans2:
+               case SMBtranss2:
+                       return process_trans2(blr);
+               default:
+                       DEBUG(0,("blocking_lock_record_process: PANIC - unknown type on blocking lock queue - exiting.!\n"));
+                       exit_server("PANIC - unknown type on blocking lock queue");
+       }
+       return False; /* Keep compiler happy. */
 }
 
 /****************************************************************************
- Process a blocking lock SMB.
- Returns True if we want to be removed from the list.
+ Cancel entries by fnum from the blocking lock pending queue.
 *****************************************************************************/
 
-static BOOL blocking_lock_record_process(blocking_lock_record *blr)
+void cancel_pending_lock_requests_by_fid(files_struct *fsp, struct byte_range_lock *br_lck)
 {
-  switch(blr->com_type) {
-  case SMBlock:
-    return process_lock(blr);
-  case SMBlockread:
-    return process_lockread(blr);
-  case SMBlockingX:
-    return process_lockingX(blr);
-  default:
-    DEBUG(0,("blocking_lock_record_process: PANIC - unknown type on blocking lock queue - exiting.!\n"));
-    exit_server("PANIC - unknown type on blocking lock queue");
-  }
-  return False; /* Keep compiler happy. */
+       blocking_lock_record *blr, *next = NULL;
+
+       for(blr = blocking_lock_queue; blr; blr = next) {
+               next = blr->next;
+               if(blr->fsp->fnum == fsp->fnum) {
+                       unsigned char locktype = 0;
+
+                       if (blr->com_type == SMBlockingX) {
+                               locktype = CVAL(blr->inbuf,smb_vwv3);
+                       }
+
+                       if (br_lck) {
+                               DEBUG(10,("remove_pending_lock_requests_by_fid - removing request type %d for \
+file %s fnum = %d\n", blr->com_type, fsp->fsp_name, fsp->fnum ));
+
+                               brl_lock_cancel(br_lck,
+                                       blr->lock_pid,
+                                       procid_self(),
+                                       blr->offset,
+                                       blr->count,
+                                       blr->lock_flav);
+
+                               blocking_lock_cancel(fsp,
+                                       blr->lock_pid,
+                                       blr->offset,
+                                       blr->count,
+                                       blr->lock_flav,
+                                       locktype,
+                                       NT_STATUS_RANGE_NOT_LOCKED);
+                       }
+                       /* We're closing the file fsp here, so ensure
+                        * we don't have a dangling pointer. */
+                       blr->fsp = NULL;
+               }
+       }
 }
 
 /****************************************************************************
- Delete entries by fnum from the blocking lock pending queue.
+ Delete entries by mid from the blocking lock pending queue. Always send reply.
 *****************************************************************************/
 
-void remove_pending_lock_requests_by_fid(files_struct *fsp)
+void remove_pending_lock_requests_by_mid(int mid)
 {
-  blocking_lock_record *blr = (blocking_lock_record *)ubi_slFirst( &blocking_lock_queue );
-  blocking_lock_record *prev = NULL;
+       blocking_lock_record *blr, *next = NULL;
 
-  while(blr != NULL) {
-    if(blr->fsp->fnum == fsp->fnum) {
+       for(blr = blocking_lock_queue; blr; blr = next) {
+               next = blr->next;
+               if(SVAL(blr->inbuf,smb_mid) == mid) {
+                       files_struct *fsp = blr->fsp;
+                       struct byte_range_lock *br_lck = brl_get_locks(NULL, fsp);
 
-      DEBUG(10,("remove_pending_lock_requests_by_fid - removing request type %d for \
+                       if (br_lck) {
+                               DEBUG(10,("remove_pending_lock_requests_by_mid - removing request type %d for \
 file %s fnum = %d\n", blr->com_type, fsp->fsp_name, fsp->fnum ));
 
-      free_blocking_lock_record((blocking_lock_record *)ubi_slRemNext( &blocking_lock_queue, prev));
-      blr = (blocking_lock_record *)(prev ? ubi_slNext(prev) : ubi_slFirst(&blocking_lock_queue));
-      continue;
-    }
+                               brl_lock_cancel(br_lck,
+                                       blr->lock_pid,
+                                       procid_self(),
+                                       blr->offset,
+                                       blr->count,
+                                       blr->lock_flav);
+                               TALLOC_FREE(br_lck);
+                       }
+
+                       blocking_lock_reply_error(blr,NT_STATUS_FILE_LOCK_CONFLICT);
+                       DLIST_REMOVE(blocking_lock_queue, blr);
+                       free_blocking_lock_record(blr);
+               }
+       }
+}
 
-    prev = blr;
-    blr = (blocking_lock_record *)ubi_slNext(blr);
-  }
+/****************************************************************************
+ Is this mid a blocking lock request on the queue ?
+*****************************************************************************/
+
+bool blocking_lock_was_deferred(int mid)
+{
+       blocking_lock_record *blr, *next = NULL;
+
+       for(blr = blocking_lock_queue; blr; blr = next) {
+               next = blr->next;
+               if(SVAL(blr->inbuf,smb_mid) == mid) {
+                       return True;
+               }
+       }
+       return False;
 }
 
 /****************************************************************************
Delete entries by mid from the blocking lock pending queue. Always send reply.
 Set a flag as an unlock request affects one of our pending locks.
 *****************************************************************************/
 
-void remove_pending_lock_requests_by_mid(int mid)
+static void received_unlock_msg(struct messaging_context *msg,
+                               void *private_data,
+                               uint32_t msg_type,
+                               struct server_id server_id,
+                               DATA_BLOB *data)
 {
-  blocking_lock_record *blr = (blocking_lock_record *)ubi_slFirst( &blocking_lock_queue );
-  blocking_lock_record *prev = NULL;
+       DEBUG(10,("received_unlock_msg\n"));
+       process_blocking_lock_queue();
+}
 
-  while(blr != NULL) {
-    if(SVAL(blr->inbuf,smb_mid) == mid) {
-      files_struct *fsp = blr->fsp;
+/****************************************************************************
+ Process the blocking lock queue. Note that this is only called as root.
+*****************************************************************************/
 
-      DEBUG(10,("remove_pending_lock_requests_by_mid - removing request type %d for \
-file %s fnum = %d\n", blr->com_type, fsp->fsp_name, fsp->fnum ));
+static void process_blocking_lock_queue(void)
+{
+       struct timeval tv_curr = timeval_current();
+       blocking_lock_record *blr, *next = NULL;
+       bool recalc_timeout = False;
+
+       /*
+        * Go through the queue and see if we can get any of the locks.
+        */
+
+       for (blr = blocking_lock_queue; blr; blr = next) {
+               connection_struct *conn = NULL;
+               uint16 vuid;
+               files_struct *fsp = NULL;
+
+               next = blr->next;
+
+               /*
+                * Ensure we don't have any old chain_fsp values
+                * sitting around....
+                */
+               chain_size = 0;
+               file_chain_reset();
+               fsp = blr->fsp;
+
+               conn = conn_find(SVAL(blr->inbuf,smb_tid));
+               vuid = (lp_security() == SEC_SHARE) ? UID_FIELD_INVALID :
+                               SVAL(blr->inbuf,smb_uid);
+
+               DEBUG(5,("process_blocking_lock_queue: examining pending lock fnum = %d for file %s\n",
+                       fsp->fnum, fsp->fsp_name ));
+
+               if(!change_to_user(conn,vuid)) {
+                       struct byte_range_lock *br_lck = brl_get_locks(NULL, fsp);
+
+                       /*
+                        * Remove the entry and return an error to the client.
+                        */
+
+                       if (br_lck) {
+                               brl_lock_cancel(br_lck,
+                                       blr->lock_pid,
+                                       procid_self(),
+                                       blr->offset,
+                                       blr->count,
+                                       blr->lock_flav);
+                               TALLOC_FREE(br_lck);
+                       }
+
+                       DEBUG(0,("process_blocking_lock_queue: Unable to become user vuid=%d.\n",
+                               vuid ));
+                       blocking_lock_reply_error(blr,NT_STATUS_ACCESS_DENIED);
+                       DLIST_REMOVE(blocking_lock_queue, blr);
+                       free_blocking_lock_record(blr);
+                       recalc_timeout = True;
+                       continue;
+               }
+
+               if(!set_current_service(conn,SVAL(blr->inbuf,smb_flg),True)) {
+                       struct byte_range_lock *br_lck = brl_get_locks(NULL, fsp);
+
+                       /*
+                        * Remove the entry and return an error to the client.
+                        */
+
+                       if (br_lck) {
+                               brl_lock_cancel(br_lck,
+                                       blr->lock_pid,
+                                       procid_self(),
+                                       blr->offset,
+                                       blr->count,
+                                       blr->lock_flav);
+                               TALLOC_FREE(br_lck);
+                       }
+
+                       DEBUG(0,("process_blocking_lock_queue: Unable to become service Error was %s.\n", strerror(errno) ));
+                       blocking_lock_reply_error(blr,NT_STATUS_ACCESS_DENIED);
+                       DLIST_REMOVE(blocking_lock_queue, blr);
+                       free_blocking_lock_record(blr);
+                       recalc_timeout = True;
+                       change_to_root_user();
+                       continue;
+               }
+
+               /*
+                * Go through the remaining locks and try and obtain them.
+                * The call returns True if all locks were obtained successfully
+                * and False if we still need to wait.
+                */
+
+               if(blocking_lock_record_process(blr)) {
+                       struct byte_range_lock *br_lck = brl_get_locks(NULL, fsp);
+
+                       if (br_lck) {
+                               brl_lock_cancel(br_lck,
+                                       blr->lock_pid,
+                                       procid_self(),
+                                       blr->offset,
+                                       blr->count,
+                                       blr->lock_flav);
+                               TALLOC_FREE(br_lck);
+                       }
+
+                       DLIST_REMOVE(blocking_lock_queue, blr);
+                       free_blocking_lock_record(blr);
+                       recalc_timeout = True;
+                       change_to_root_user();
+                       continue;
+               }
+
+               change_to_root_user();
+
+               /*
+                * We couldn't get the locks for this record on the list.
+                * If the time has expired, return a lock error.
+                */
+
+               if (!timeval_is_zero(&blr->expire_time) && timeval_compare(&blr->expire_time, &tv_curr) <= 0) {
+                       struct byte_range_lock *br_lck = brl_get_locks(NULL, fsp);
+
+                       /*
+                        * Lock expired - throw away all previously
+                        * obtained locks and return lock error.
+                        */
+
+                       if (br_lck) {
+                               DEBUG(5,("process_blocking_lock_queue: pending lock fnum = %d for file %s timed out.\n",
+                                       fsp->fnum, fsp->fsp_name ));
+
+                               brl_lock_cancel(br_lck,
+                                       blr->lock_pid,
+                                       procid_self(),
+                                       blr->offset,
+                                       blr->count,
+                                       blr->lock_flav);
+                               TALLOC_FREE(br_lck);
+                       }
+
+                       blocking_lock_reply_error(blr,NT_STATUS_FILE_LOCK_CONFLICT);
+                       DLIST_REMOVE(blocking_lock_queue, blr);
+                       free_blocking_lock_record(blr);
+                       recalc_timeout = True;
+               }
+       }
+
+       if (recalc_timeout) {
+               recalc_brl_timeout();
+       }
+}
 
-      blocking_lock_reply_error(blr,0,NT_STATUS_CANCELLED);
-      free_blocking_lock_record((blocking_lock_record *)ubi_slRemNext( &blocking_lock_queue, prev));
-      blr = (blocking_lock_record *)(prev ? ubi_slNext(prev) : ubi_slFirst(&blocking_lock_queue));
-      continue;
-    }
+/****************************************************************************
+ Handle a cancel message. Lock already moved onto the cancel queue.
+*****************************************************************************/
 
-    prev = blr;
-    blr = (blocking_lock_record *)ubi_slNext(blr);
-  }
+#define MSG_BLOCKING_LOCK_CANCEL_SIZE (sizeof(blocking_lock_record *) + sizeof(NTSTATUS))
+
+static void process_blocking_lock_cancel_message(struct messaging_context *ctx,
+                                                void *private_data,
+                                                uint32_t msg_type,
+                                                struct server_id server_id,
+                                                DATA_BLOB *data)
+{
+       NTSTATUS err;
+       const char *msg = (const char *)data->data;
+       blocking_lock_record *blr;
+
+       if (data->data == NULL) {
+               smb_panic("process_blocking_lock_cancel_message: null msg");
+       }
+
+       if (data->length != MSG_BLOCKING_LOCK_CANCEL_SIZE) {
+               DEBUG(0, ("process_blocking_lock_cancel_message: "
+                         "Got invalid msg len %d\n", (int)data->length));
+               smb_panic("process_blocking_lock_cancel_message: bad msg");
+        }
+
+       memcpy(&blr, msg, sizeof(blr));
+       memcpy(&err, &msg[sizeof(blr)], sizeof(NTSTATUS));
+
+       DEBUG(10,("process_blocking_lock_cancel_message: returning error %s\n",
+               nt_errstr(err) ));
+
+       blocking_lock_reply_error(blr, err);
+       DLIST_REMOVE(blocking_lock_cancelled_queue, blr);
+       free_blocking_lock_record(blr);
 }
 
 /****************************************************************************
Process the blocking lock queue. Note that this is only called as root.
Send ourselves a blocking lock cancelled message. Handled asynchronously above.
 *****************************************************************************/
 
-void process_blocking_lock_queue(time_t t)
+bool blocking_lock_cancel(files_struct *fsp,
+                       uint32 lock_pid,
+                       SMB_BIG_UINT offset,
+                       SMB_BIG_UINT count,
+                       enum brl_flavour lock_flav,
+                       unsigned char locktype,
+                        NTSTATUS err)
 {
-  blocking_lock_record *blr = (blocking_lock_record *)ubi_slFirst( &blocking_lock_queue );
-  blocking_lock_record *prev = NULL;
-
-  if(blr == NULL)
-    return;
-
-  /*
-   * Go through the queue and see if we can get any of the locks.
-   */
-
-  while(blr != NULL) {
-    connection_struct *conn = NULL;
-    uint16 vuid;
-    files_struct *fsp = NULL;
-
-    /*
-     * Ensure we don't have any old chain_fsp values
-     * sitting around....
-     */
-    chain_size = 0;
-    file_chain_reset();
-    fsp = blr->fsp;
-
-    conn = conn_find(SVAL(blr->inbuf,smb_tid));
-    vuid = (lp_security() == SEC_SHARE) ? UID_FIELD_INVALID :
-                  SVAL(blr->inbuf,smb_uid);
-
-    DEBUG(5,("process_blocking_lock_queue: examining pending lock fnum = %d for file %s\n",
-          fsp->fnum, fsp->fsp_name ));
-
-    if((blr->expire_time != -1) && (blr->expire_time > t)) {
-      /*
-       * Lock expired - throw away all previously
-       * obtained locks and return lock error.
-       */
-      DEBUG(5,("process_blocking_lock_queue: pending lock fnum = %d for file %s timed out.\n",
-          fsp->fnum, fsp->fsp_name ));
-
-      blocking_lock_reply_error(blr,ERRSRV,ERRaccess);
-      free_blocking_lock_record((blocking_lock_record *)ubi_slRemNext( &blocking_lock_queue, prev));
-      blr = (blocking_lock_record *)(prev ? ubi_slNext(prev) : ubi_slFirst(&blocking_lock_queue));
-      continue;
-    }
-
-    if(!become_user(conn,vuid)) {
-      DEBUG(0,("process_blocking_lock_queue: Unable to become user vuid=%d.\n",
-            vuid ));
-      /*
-       * Remove the entry and return an error to the client.
-       */
-      blocking_lock_reply_error(blr,ERRSRV,ERRaccess);
-      free_blocking_lock_record((blocking_lock_record *)ubi_slRemNext( &blocking_lock_queue, prev));
-      blr = (blocking_lock_record *)(prev ? ubi_slNext(prev) : ubi_slFirst(&blocking_lock_queue));
-      continue;
-    }
-
-    if(!become_service(conn,True)) {
-      DEBUG(0,("process_blocking_lock_queue: Unable to become service Error was %s.\n", strerror(errno) ));
-      /*
-       * Remove the entry and return an error to the client.
-       */
-      blocking_lock_reply_error(blr,ERRSRV,ERRaccess);
-      free_blocking_lock_record((blocking_lock_record *)ubi_slRemNext( &blocking_lock_queue, prev));
-      blr = (blocking_lock_record *)(prev ? ubi_slNext(prev) : ubi_slFirst(&blocking_lock_queue));
-      unbecome_user();
-      continue;
-    }
-
-    /*
-     * Go through the remaining locks and try and obtain them.
-     * The call returns True if all locks were obtained successfully
-     * and False if we still need to wait.
-     */
-
-    if(blocking_lock_record_process(blr)) {
-      free_blocking_lock_record((blocking_lock_record *)ubi_slRemNext( &blocking_lock_queue, prev));
-      blr = (blocking_lock_record *)(prev ? ubi_slNext(prev) : ubi_slFirst(&blocking_lock_queue));
-      unbecome_user();
-      continue;
-    }
-
-    unbecome_user();
-
-    /*
-     * Move to the next in the list.
-     */
-    prev = blr;
-    blr = (blocking_lock_record *)ubi_slNext(blr);
-  }
+       static bool initialized;
+       char msg[MSG_BLOCKING_LOCK_CANCEL_SIZE];
+       blocking_lock_record *blr;
+
+       if (!initialized) {
+               /* Register our message. */
+               messaging_register(smbd_messaging_context(), NULL,
+                                  MSG_SMB_BLOCKING_LOCK_CANCEL,
+                                  process_blocking_lock_cancel_message);
+
+               initialized = True;
+       }
+
+       for (blr = blocking_lock_queue; blr; blr = blr->next) {
+               if (fsp == blr->fsp &&
+                               lock_pid == blr->lock_pid &&
+                               offset == blr->offset &&
+                               count == blr->count &&
+                               lock_flav == blr->lock_flav) {
+                       break;
+               }
+       }
+
+       if (!blr) {
+               return False;
+       }
+
+       /* Check the flags are right. */
+       if (blr->com_type == SMBlockingX &&
+               (locktype & LOCKING_ANDX_LARGE_FILES) !=
+                       (CVAL(blr->inbuf,smb_vwv3) & LOCKING_ANDX_LARGE_FILES)) {
+               return False;
+       }
+
+       /* Move to cancelled queue. */
+       DLIST_REMOVE(blocking_lock_queue, blr);
+       DLIST_ADD(blocking_lock_cancelled_queue, blr);
+
+       /* Create the message. */
+       memcpy(msg, &blr, sizeof(blr));
+       memcpy(&msg[sizeof(blr)], &err, sizeof(NTSTATUS));
+
+       messaging_send_buf(smbd_messaging_context(), procid_self(),
+                          MSG_SMB_BLOCKING_LOCK_CANCEL,
+                          (uint8 *)&msg, sizeof(msg));
+
+       return True;
 }