source3/smbd/oplock_irix.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    IRIX kernel oplock processing
   4    Copyright (C) Andrew Tridgell 1992-1998
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 2 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program; if not, write to the Free Software
  18    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  19 */
  20
  21 #include "includes.h"
  22
  23 #if HAVE_KERNEL_OPLOCKS_IRIX
  24
  25 static int oplock_pipe_write = -1;
  26 static int oplock_pipe_read = -1;
  27
  28 /****************************************************************************
  29  Test to see if IRIX kernel oplocks work.
  30 ****************************************************************************/
  31
  32 static BOOL irix_oplocks_available(void)
  33 {
  34         int fd;
  35         int pfd[2];
  36         pstring tmpname;
  37
  38         oplock_set_capability(True, False);
  39
  40         slprintf(tmpname,sizeof(tmpname)-1, "%s/koplock.%d", lp_lockdir(), (int)sys_getpid());
  41
  42         if(pipe(pfd) != 0) {
  43                 DEBUG(0,("check_kernel_oplocks: Unable to create pipe. Error was %s\n",
  44                          strerror(errno) ));
  45                 return False;
  46         }
  47
  48         if((fd = sys_open(tmpname, O_RDWR|O_CREAT|O_EXCL|O_TRUNC, 0600)) < 0) {
  49                 DEBUG(0,("check_kernel_oplocks: Unable to open temp test file %s. Error was %s\n",
  50                          tmpname, strerror(errno) ));
  51                 unlink( tmpname );
  52                 close(pfd[0]);
  53                 close(pfd[1]);
  54                 return False;
  55         }
  56
  57         unlink(tmpname);
  58
  59         if(sys_fcntl_long(fd, F_OPLKREG, pfd[1]) == -1) {
  60                 DEBUG(0,("check_kernel_oplocks: Kernel oplocks are not available on this machine. \
  61 Disabling kernel oplock support.\n" ));
  62                 close(pfd[0]);
  63                 close(pfd[1]);
  64                 close(fd);
  65                 return False;
  66         }
  67
  68         if(sys_fcntl_long(fd, F_OPLKACK, OP_REVOKE) < 0 ) {
  69                 DEBUG(0,("check_kernel_oplocks: Error when removing kernel oplock. Error was %s. \
  70 Disabling kernel oplock support.\n", strerror(errno) ));
  71                 close(pfd[0]);
  72                 close(pfd[1]);
  73                 close(fd);
  74                 return False;
  75         }
  76
  77         close(pfd[0]);
  78         close(pfd[1]);
  79         close(fd);
  80
  81         return True;
  82 }
  83
  84 /****************************************************************************
  85  * Deal with the IRIX kernel <--> smbd
  86  * oplock break protocol.
  87 ****************************************************************************/
  88
  89 static files_struct *irix_oplock_receive_message(fd_set *fds)
  90 {
  91         extern int smb_read_error;
  92         oplock_stat_t os;
  93         char dummy;
  94         files_struct *fsp;
  95
  96         /* Ensure we only get one call per select fd set. */
  97         FD_CLR(fds, oplock_pipe_read);
  98
  99         /*
 100          * Read one byte of zero to clear the
 101          * kernel break notify message.
 102          */
 103
 104         if(read(oplock_pipe_read, &dummy, 1) != 1) {
 105                 DEBUG(0,("irix_oplock_receive_message: read of kernel "
 106                          "notification failed. Error was %s.\n",
 107                          strerror(errno) ));
 108                 smb_read_error = READ_ERROR;
 109                 return NULL;
 110         }
 111
 112         /*
 113          * Do a query to get the
 114          * device and inode of the file that has the break
 115          * request outstanding.
 116          */
 117
 118         if(sys_fcntl_ptr(oplock_pipe_read, F_OPLKSTAT, &os) < 0) {
 119                 DEBUG(0,("irix_oplock_receive_message: fcntl of kernel "
 120                          "notification failed. Error was %s.\n",
 121                          strerror(errno) ));
 122                 if(errno == EAGAIN) {
 123                         /*
 124                          * Duplicate kernel break message - ignore.
 125                          */
 126                         return NULL;
 127                 }
 128                 smb_read_error = READ_ERROR;
 129                 return NULL;
 130         }
 131
 132         /*
 133          * We only have device and inode info here - we have to guess that this
 134          * is the first fsp open with this dev,ino pair.
 135          */
 136
 137         if ((fsp = file_find_di_first((SMB_DEV_T)os.os_dev,
 138                                       (SMB_INO_T)os.os_ino)) == NULL) {
 139                 DEBUG(0,("irix_oplock_receive_message: unable to find open "
 140                          "file with dev = %x, inode = %.0f\n",
 141                          (unsigned int)os.os_dev, (double)os.os_ino ));
 142                 return NULL;
 143         }
 144
 145         DEBUG(5,("irix_oplock_receive_message: kernel oplock break request "
 146                  "received for dev = %x, inode = %.0f\n, file_id = %ul",
 147                  (unsigned int)fsp->dev, (double)fsp->inode, fsp->file_id ));
 148
 149         return fsp;
 150 }
 151
 152 /****************************************************************************
 153  Attempt to set an kernel oplock on a file.
 154 ****************************************************************************/
 155
 156 static BOOL irix_set_kernel_oplock(files_struct *fsp, int oplock_type)
 157 {
 158         if (sys_fcntl_long(fsp->fh->fd, F_OPLKREG, oplock_pipe_write) == -1) {
 159                 if(errno != EAGAIN) {
 160                         DEBUG(0,("irix_set_kernel_oplock: Unable to get kernel oplock on file %s, dev = %x, \
 161 inode = %.0f, file_id = %ul. Error was %s\n",
 162                                  fsp->fsp_name, (unsigned int)fsp->dev, (double)fsp->inode, fsp->file_id,
 163                                  strerror(errno) ));
 164                 } else {
 165                         DEBUG(5,("irix_set_kernel_oplock: Refused oplock on file %s, fd = %d, dev = %x, \
 166 inode = %.0f, file_id = %ul. Another process had the file open.\n",
 167                                  fsp->fsp_name, fsp->fh->fd, (unsigned int)fsp->dev, (double)fsp->inode, fsp->file_id ));
 168                 }
 169                 return False;
 170         }
 171
 172         DEBUG(10,("irix_set_kernel_oplock: got kernel oplock on file %s, dev = %x, inode = %.0f, file_id = %ul\n",
 173                   fsp->fsp_name, (unsigned int)fsp->dev, (double)fsp->inode, fsp->file_id));
 174
 175         return True;
 176 }
 177
 178 /****************************************************************************
 179  Release a kernel oplock on a file.
 180 ****************************************************************************/
 181
 182 static void irix_release_kernel_oplock(files_struct *fsp)
 183 {
 184         if (DEBUGLVL(10)) {
 185                 /*
 186                  * Check and print out the current kernel
 187                  * oplock state of this file.
 188                  */
 189                 int state = sys_fcntl_long(fsp->fh->fd, F_OPLKACK, -1);
 190                 dbgtext("irix_release_kernel_oplock: file %s, dev = %x, inode = %.0f file_id = %ul, has kernel \
 191 oplock state of %x.\n", fsp->fsp_name, (unsigned int)fsp->dev,
 192                         (double)fsp->inode, fsp->file_id, state );
 193         }
 194
 195         /*
 196          * Remove the kernel oplock on this file.
 197          */
 198         if(sys_fcntl_long(fsp->fh->fd, F_OPLKACK, OP_REVOKE) < 0) {
 199                 if( DEBUGLVL( 0 )) {
 200                         dbgtext("irix_release_kernel_oplock: Error when removing kernel oplock on file " );
 201                         dbgtext("%s, dev = %x, inode = %.0f, file_id = %ul. Error was %s\n",
 202                                 fsp->fsp_name, (unsigned int)fsp->dev,
 203                                 (double)fsp->inode, fsp->file_id, strerror(errno) );
 204                 }
 205         }
 206 }
 207
 208 /****************************************************************************
 209  Set *maxfd to include oplock read pipe.
 210  Note that fds MAY BE NULL ! If so we must do our own select.
 211 ****************************************************************************/
 212
 213 static BOOL irix_oplock_msg_waiting(fd_set *fds)
 214 {
 215         int maxfd, selrtn;
 216         fd_set myfds;
 217         struct timeval to;
 218
 219         if (oplock_pipe_read == -1)
 220                 return False;
 221
 222         if (fds) {
 223                 return FD_ISSET(oplock_pipe_read,fds);
 224         }
 225
 226         FD_ZERO(&myfds);
 227         maxfd = setup_oplock_select_set(&myfds);
 228         /* Only do the select if we have something to select *on*. */
 229         if (maxfd == 0) {
 230                 return False;
 231         }
 232
 233         /* Do a zero-time select. We just need to find out if there
 234          * are any outstanding messages. We use sys_select_intr as
 235          * we need to ignore any signals. */
 236
 237         to = timeval_set(0, 0);
 238         selrtn = sys_select_intr(maxfd+1,&myfds,NULL,NULL,&to);
 239         return (selrtn == 1) ? True : False;
 240 }
 241
 242 /****************************************************************************
 243  Setup kernel oplocks.
 244 ****************************************************************************/
 245
 246 struct kernel_oplocks *irix_init_kernel_oplocks(void)
 247 {
 248         int pfd[2];
 249         static struct kernel_oplocks koplocks;
 250
 251         if (!irix_oplocks_available())
 252                 return NULL;
 253
 254         if(pipe(pfd) != 0) {
 255                 DEBUG(0,("setup_kernel_oplock_pipe: Unable to create pipe. Error was %s\n",
 256                          strerror(errno) ));
 257                 return False;
 258         }
 259
 260         oplock_pipe_read = pfd[0];
 261         oplock_pipe_write = pfd[1];
 262
 263         koplocks.receive_message = irix_oplock_receive_message;
 264         koplocks.set_oplock = irix_set_kernel_oplock;
 265         koplocks.release_oplock = irix_release_kernel_oplock;
 266         koplocks.msg_waiting = irix_oplock_msg_waiting;
 267         koplocks.notification_fd = oplock_pipe_read;
 268
 269         return &koplocks;
 270 }
 271 #else
 272  void oplock_irix_dummy(void) {}
 273 #endif /* HAVE_KERNEL_OPLOCKS_IRIX */