nnpfs/bsd/nnpfs_dev-freebsd.c

   1 /*
   2  * Copyright (c) 1995 - 2007 Kungliga Tekniska Högskolan
   3  * (Royal Institute of Technology, Stockholm, Sweden).
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  *
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  *
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  *
  17  * 3. Neither the name of the Institute nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34
  35 #include <nnpfs/nnpfs_locl.h>
  36 #include <nnpfs/nnpfs_message.h>
  37 #include <nnpfs/nnpfs_msg_locl.h>
  38 #include <nnpfs/nnpfs_fs.h>
  39 #include <nnpfs/nnpfs_dev.h>
  40 #include <nnpfs/nnpfs_deb.h>
  41
  42 RCSID("$Id$");
  43
  44 #define NNPFS_FBSD_DEVLOCK
  45
  46 #if 1
  47 void
  48 nnpfs_dev_lock(struct nnpfs *chan)
  49 {
  50     d_thread_t *me = curthread;
  51
  52     NNPFSDEB(XDEBDEV, ("nnpfs_dev_lock, me=%p\n", me));
  53
  54     mtx_lock(&chan->lock.lock);
  55
  56     while (chan->lock.recurse > 0 && chan->lock.locker != me) {
  57         /* XXX PCATCH */
  58 #if 1
  59         (void)nnpfs_msleep(&chan->lock, &chan->lock.lock, (PZERO + 1), "nnpfslock");
  60 #else
  61         int ret = 0;
  62         while msleep(&chan->lock, &chan->lock.lock, (PZERO + 1), "nnpfslock", 7 * hz);
  63
  64 #endif
  65     }
  66
  67     chan->lock.locker = me;
  68     nnpfs_assert(chan->lock.recurse >= 0);
  69     chan->lock.recurse++;
  70
  71     NNPFSDEB(XDEBDEV, ("nnpfs_dev_lock, locker %p\n", chan->lock.locker));
  72
  73     mtx_unlock(&chan->lock.lock);
  74 }
  75
  76 void
  77 nnpfs_dev_unlock(struct nnpfs *chan)
  78 {
  79     d_thread_t *me = curthread;
  80
  81     NNPFSDEB(XDEBDEV, ("nnpfs_dev_unlock, me=%p locker=%p r=%d\n", me,
  82                        chan->lock.locker, chan->lock.recurse));
  83
  84     mtx_lock(&chan->lock.lock);
  85
  86     chan->lock.recurse--;
  87     nnpfs_assert(chan->lock.recurse >= 0);
  88     nnpfs_assert(chan->lock.locker == me);
  89
  90     if (chan->lock.recurse == 0) {
  91         chan->lock.locker = NULL;
  92         wakeup(&chan->lock);
  93     }
  94
  95     mtx_unlock(&chan->lock.lock);
  96 }
  97
  98 int
  99 nnpfs_dev_msleep(struct nnpfs *chan, caddr_t waitobj, int flags, const char *msg)
 100 {
 101     d_thread_t *me = curthread;
 102     int ret, nlocks;
 103
 104     NNPFSDEB(XDEBDEV, ("nnpfs_dev_msleep %p %x %s, me %p\n", waitobj, flags, msg, me));
 105
 106     mtx_lock(&chan->lock.lock);
 107     nlocks = chan->lock.recurse;
 108     nnpfs_assert(chan->lock.recurse >= 0);
 109     nnpfs_assert(chan->lock.locker == me);
 110
 111     chan->lock.recurse = 0;
 112     chan->lock.locker = NULL;
 113     wakeup(&chan->lock);
 114
 115     ret = nnpfs_msleep(waitobj, &chan->lock.lock, flags, msg);
 116
 117     while (chan->lock.recurse > 0)
 118         /* XXX PCATCH, flags, ret? */
 119         (void)nnpfs_msleep(&chan->lock, &chan->lock.lock, (PZERO + 1), "nnpfslock");
 120
 121     nnpfs_assert(chan->lock.recurse == 0);
 122     chan->lock.locker = me;
 123     chan->lock.recurse = nlocks;
 124
 125     mtx_unlock(&chan->lock.lock);
 126     return ret;
 127 }
 128
 129 int
 130 nnpfs_dev_initlock(struct nnpfs *chan)
 131 {
 132     d_thread_t *me = curthread;
 133
 134     NNPFSDEB(XDEBDEV, ("nnpfs_dev_initlock\n"));
 135
 136     if (mtx_initialized(&chan->lock.lock))
 137         panic("nnpfs_dev_initlock: already inited!");
 138
 139     mtx_init(&chan->lock.lock, "nnpfsdevlock", NULL, MTX_DEF);
 140
 141     mtx_lock(&chan->lock.lock);
 142     chan->lock.locker = me;
 143     chan->lock.recurse = 1;
 144     mtx_unlock(&chan->lock.lock);
 145
 146     return 0;
 147 }
 148
 149 void
 150 nnpfs_dev_uninitlock(struct nnpfs *chan)
 151 {
 152     d_thread_t *me = curthread;
 153
 154     NNPFSDEB(XDEBDEV, ("nnpfs_dev_uninitlock\n"));
 155
 156     if (!mtx_initialized(&chan->lock.lock))
 157         printf("nnpfs_dev_uninitlock: not inited!\n");
 158
 159     mtx_lock(&chan->lock.lock);
 160     nnpfs_assert(chan->lock.recurse == 1);
 161     nnpfs_assert(chan->lock.locker == me);
 162
 163     chan->lock.recurse = 0;
 164     chan->lock.locker = NULL;
 165
 166     /*
 167      * contrary to man page, it seems we need to unlock the mutex before
 168      * destroying it if we use spinlocks. Default mutexes are ok.
 169      */
 170
 171     mtx_destroy(&chan->lock.lock);
 172 }
 173 #else
 174
 175 void
 176 nnpfs_dev_lock(struct nnpfs *chan)
 177 {
 178     int ret;
 179     NNPFSDEB(XDEBDEV, ("nnpfs_dev_lock\n"));
 180     ret = lockmgr(&chan->dev_lock, LK_EXCLUSIVE | LK_CANRECURSE, NULL);
 181     nnpfs_assert(!ret);
 182 }
 183
 184 void
 185 nnpfs_dev_unlock(struct nnpfs *chan)
 186 {
 187     int ret;
 188     NNPFSDEB(XDEBDEV, ("nnpfs_dev_unlock\n"));
 189     ret = lockmgr(&chan->dev_lock, LK_RELEASE, NULL);
 190     nnpfs_assert(!ret);
 191 }
 192
 193 int
 194 nnpfs_dev_msleep(struct nnpfs *chan, caddr_t waitobj, int flags, const char *msg)
 195 {
 196     d_thread_t *td = curthread;
 197     int nlocks, i, ret;
 198
 199     NNPFSDEB(XDEBDEV, ("nnpfs_dev_msleep %p %x %s\n", waitobj, flags, msg));
 200
 201     ret = lockstatus(&chan->dev_lock, td);
 202     nnpfs_assert(ret == LK_EXCLUSIVE);
 203
 204     nlocks = lockcount(&chan->dev_lock);
 205
 206     for (i = nlocks; i > 0 ; i--) {
 207         ret = lockmgr(&chan->dev_lock, LK_RELEASE, NULL);
 208         nnpfs_assert(!ret);
 209     }
 210
 211     ret = nnpfs_msleep(waitobj, &chan->dev_lock, flags, msg);
 212     return ret;
 213 }
 214
 215 int
 216 nnpfs_dev_initlock(struct nnpfs *chan)
 217 {
 218     NNPFSDEB(XDEBDEV, ("nnpfs_dev_initlock\n"));
 219     lockinit(&chan->dev_lock, PRIBIO /* XXX */, "nnpfsdevlock", NULL, LK_CANRECURSE | LK_NOSHARE);
 220     return lockmgr(&chan->dev_lock, LK_EXCLUSIVE, NULL);
 221 }
 222
 223 void
 224 nnpfs_dev_uninitlock(struct nnpfs *chan)
 225 {
 226     NNPFSDEB(XDEBDEV, ("nnpfs_dev_uninitlock\n"));
 227     lockdestroy(&chan->dev_lock);
 228 }
 229
 230 #endif
 231
 232 #ifndef NNPFS_FBSD_DEVLOCK
 233
 234 #ifndef D_NEEDGIANT
 235 #define D_NEEDGIANT 0
 236 #endif
 237
 238 #endif
 239
 240 struct cdevsw nnpfs_cdev = {
 241 #if __FreeBSD_version >= 502103
 242     d_version: D_VERSION,
 243 #endif
 244     d_name: "nnpfs",
 245     d_open: nnpfs_devopen,
 246     d_close: nnpfs_devclose,
 247     d_read: nnpfs_devread,
 248     d_write: nnpfs_devwrite,
 249     d_ioctl: nnpfs_devioctl,
 250 #ifdef HAVE_STRUCT_CDEVSW_D_MMAP
 251     d_mmap: nommap,
 252 #endif
 253 #ifdef HAVE_STRUCT_CDEVSW_D_STRATEGY
 254     d_strategy: nostrategy,
 255 #endif
 256     /*
 257      * Giant is no longer needed, nnpfs_node_find & friends are locked
 258      * now, verify correctness before removing.
 259      */
 260 #ifdef NNPFS_FBSD_DEVLOCK
 261     d_flags: 0,
 262 #else
 263     d_flags: D_NEEDGIANT,
 264 #endif
 265
 266 #ifdef HAVE_STRUCT_CDEVSW_D_STOP
 267     d_stop: nostop,
 268 #endif
 269 #ifdef HAVE_STRUCT_CDEVSW_D_RESET
 270     d_reset: noreset,
 271 #endif
 272 #ifdef HAVE_STRUCT_CDEVSW_D_BOGORESET
 273     d_bogoreset: noreset,
 274 #endif
 275 #ifdef HAVE_STRUCT_CDEVSW_D_DEVTOTTY
 276     d_devtotty: nodevtotty,
 277 #endif
 278 #if defined(HAVE_VOP_SELECT)
 279     d_select: nnpfs_devselect,
 280 #elif defined(HAVE_VOP_POLL)
 281     d_poll: nnpfs_devpoll,
 282 #else
 283 #error select or poll: that is the question
 284 #endif
 285 #ifdef HAVE_STRUCT_CDEVSW_D_BOGOPARMS
 286     d_bogoparms: noparms,
 287 #endif
 288 #ifdef HAVE_STRUCT_CDEVSW_D_SPARE
 289     d_spare: NULL,
 290 #endif
 291 #if __FreeBSD_version < 600007
 292     d_maj: 128,                 /* XXX */
 293 #endif
 294 #ifdef HAVE_STRUCT_CDEVSW_D_DUMP
 295     d_dump: nodump,
 296 #endif
 297 #ifdef HAVE_STRUCT_CDEVSW_D_PSIZE
 298     d_psize: nopsize,
 299 #endif
 300 #ifdef HAVE_STRUCT_CDEVSW_D_MAXIO
 301     d_maxio: 0,
 302 #endif
 303 #ifdef HAVE_STRUCT_CDEVSW_D_BMAJ
 304 #ifdef NOUDEV
 305     d_bmaj: NOUDEV
 306 #else
 307     d_bmaj: NODEV
 308 #endif
 309 #endif /* HAVE_STRUCT_CDEVSW_D_BMAJ */
 310 };