sys/vfs/nfs/nfs_iod.c

   1 /*
   2  * Copyright (c) 2009 The DragonFly Project.  All rights reserved.
   3  *
   4  * This code is derived from software contributed to The DragonFly Project
   5  * by Matthew Dillon <dillon@backplane.com>
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  *
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in
  15  *    the documentation and/or other materials provided with the
  16  *    distribution.
  17  * 3. Neither the name of The DragonFly Project nor the names of its
  18  *    contributors may be used to endorse or promote products derived
  19  *    from this software without specific, prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  22  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  23  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  24  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
  25  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  26  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
  27  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  28  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
  29  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  30  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  31  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  */
  34 /*
  35  * NFSIOD operations - now built into the kernel.
  36  */
  37 #include <sys/param.h>
  38 #include <sys/systm.h>
  39 #include <sys/proc.h>
  40 #include <sys/malloc.h>
  41 #include <sys/mount.h>
  42 #include <sys/kernel.h>
  43 #include <sys/mbuf.h>
  44 #include <sys/vnode.h>
  45 #include <sys/fcntl.h>
  46 #include <sys/protosw.h>
  47 #include <sys/resourcevar.h>
  48 #include <sys/socket.h>
  49 #include <sys/socketvar.h>
  50 #include <sys/socketops.h>
  51 #include <sys/syslog.h>
  52 #include <sys/thread.h>
  53 #include <sys/tprintf.h>
  54 #include <sys/sysctl.h>
  55 #include <sys/signalvar.h>
  56 #include <sys/mutex.h>
  57
  58 #include <sys/signal2.h>
  59 #include <sys/thread2.h>
  60 #include <sys/mutex2.h>
  61 #include <sys/mplock2.h>
  62
  63 #include <netinet/in.h>
  64 #include <netinet/tcp.h>
  65
  66 #include "rpcv2.h"
  67 #include "nfsproto.h"
  68 #include "nfs.h"
  69 #include "xdr_subs.h"
  70 #include "nfsm_subs.h"
  71 #include "nfsmount.h"
  72 #include "nfsnode.h"
  73 #include "nfsrtt.h"
  74
  75 /*
  76  * nfs service connection reader thread
  77  */
  78 void
  79 nfssvc_iod_reader(void *arg)
  80 {
  81         struct nfsmount *nmp = arg;
  82         struct nfsm_info *info;
  83         struct nfsreq *req;
  84         int error;
  85
  86         get_mplock();
  87
  88         if (nmp->nm_rxstate == NFSSVC_INIT)
  89                 nmp->nm_rxstate = NFSSVC_PENDING;
  90         crit_enter();
  91         for (;;) {
  92                 if (nmp->nm_rxstate == NFSSVC_WAITING) {
  93                         if (TAILQ_FIRST(&nmp->nm_reqq) == NULL &&
  94                             TAILQ_FIRST(&nmp->nm_reqrxq) == NULL) {
  95                                 tsleep(&nmp->nm_rxstate, 0, "nfsidl", 0);
  96                         } else {
  97                                 /*
  98                                  * This can happen during shutdown, we don't
  99                                  * want to hardloop.
 100                                  */
 101                                 error = nfs_reply(nmp, NULL);
 102                                 if (error && error != EWOULDBLOCK) {
 103                                         tsleep(&nmp->nm_rxstate, 0,
 104                                                 "nfsxxx", hz / 10);
 105                                 }
 106                         }
 107                         continue;
 108                 }
 109                 if (nmp->nm_rxstate != NFSSVC_PENDING)
 110                         break;
 111                 nmp->nm_rxstate = NFSSVC_WAITING;
 112
 113                 /*
 114                  * Process requests which have received replies.  Only
 115                  * process the post-reply states.  If we get EINPROGRESS
 116                  * it means the request went back to an auth or retransmit
 117                  * state and we let the iod_writer thread deal with it.
 118                  *
 119                  * Any lock on the request is strictly temporary due to
 120                  * MP races (XXX).
 121                  *
 122                  * If the request completes we run the info->done call
 123                  * to finish up the I/O.
 124                  */
 125                 while ((req = TAILQ_FIRST(&nmp->nm_reqrxq)) != NULL) {
 126                         if (req->r_flags & R_LOCKED) {
 127                                 while (req->r_flags & R_LOCKED) {
 128                                         req->r_flags |= R_WANTED;
 129                                         tsleep(req, 0, "nfstrac", 0);
 130                                 }
 131                                 continue;
 132                         }
 133                         TAILQ_REMOVE(&nmp->nm_reqrxq, req, r_chain);
 134                         crit_exit();
 135                         info = req->r_info;
 136                         KKASSERT(info);
 137                         info->error = nfs_request(info,
 138                                                   NFSM_STATE_PROCESSREPLY,
 139                                                   NFSM_STATE_DONE);
 140                         if (info->error == EINPROGRESS) {
 141                                 kprintf("rxq: move info %p back to txq\n", info);
 142                                 TAILQ_INSERT_TAIL(&nmp->nm_reqtxq, req, r_chain);
 143                                 nfssvc_iod_writer_wakeup(nmp);
 144                         } else {
 145                                 atomic_subtract_int(&nmp->nm_bioqlen, 1);
 146                                 info->done(info);
 147                         }
 148                         crit_enter();
 149                 }
 150         }
 151         crit_exit();
 152         nmp->nm_rxthread = NULL;
 153         nmp->nm_rxstate = NFSSVC_DONE;
 154         wakeup(&nmp->nm_rxthread);
 155 }
 156
 157 /*
 158  * nfs service connection writer thread
 159  *
 160  * The writer sits on the send side of the client's socket and
 161  * does both the initial processing of BIOs and also transmission
 162  * and retransmission of nfsreq's.
 163  *
 164  * The writer processes both new BIOs from nm_bioq and retransmit
 165  * or state machine jumpbacks from nm_reqtxq
 166  */
 167 void
 168 nfssvc_iod_writer(void *arg)
 169 {
 170         struct nfsmount *nmp = arg;
 171         struct bio *bio;
 172         struct nfsreq *req;
 173         struct vnode *vp;
 174         nfsm_info_t info;
 175
 176         get_mplock();
 177
 178         if (nmp->nm_txstate == NFSSVC_INIT)
 179                 nmp->nm_txstate = NFSSVC_PENDING;
 180
 181         crit_enter();
 182         for (;;) {
 183                 if (nmp->nm_txstate == NFSSVC_WAITING) {
 184                         tsleep(&nmp->nm_txstate, 0, "nfsidl", 0);
 185                         continue;
 186                 }
 187                 if (nmp->nm_txstate != NFSSVC_PENDING)
 188                         break;
 189                 nmp->nm_txstate = NFSSVC_WAITING;
 190
 191                 /*
 192                  * Eep, we could blow out the mbuf allocator if we just
 193                  * did everything the kernel wanted us to do.
 194                  */
 195                 while ((bio = TAILQ_FIRST(&nmp->nm_bioq)) != NULL) {
 196                         if (nmp->nm_reqqlen > nfs_maxasyncbio)
 197                                 break;
 198                         TAILQ_REMOVE(&nmp->nm_bioq, bio, bio_act);
 199                         vp = bio->bio_driver_info;
 200                         crit_exit();
 201                         nfs_startio(vp, bio, NULL);
 202                         crit_enter();
 203                 }
 204
 205                 /*
 206                  * Process reauths & retransmits.  If we get an EINPROGRESS
 207                  * it means the state transitioned to WAITREPLY or later.
 208                  * Otherwise the request completed (probably with an error
 209                  * since we didn't get to a replied state).
 210                  */
 211                 while ((req = TAILQ_FIRST(&nmp->nm_reqtxq)) != NULL) {
 212                         TAILQ_REMOVE(&nmp->nm_reqtxq, req, r_chain);
 213                         info = req->r_info;
 214                         KKASSERT(info);
 215                         crit_exit();
 216                         info->error = nfs_request(info,
 217                                                   NFSM_STATE_AUTH,
 218                                                   NFSM_STATE_WAITREPLY);
 219                         crit_enter();
 220                         if (info->error == EINPROGRESS) {
 221                                 ;
 222                         } else {
 223                                 atomic_subtract_int(&nmp->nm_bioqlen, 1);
 224                                 info->done(info);
 225                         }
 226                 }
 227         }
 228         crit_exit();
 229         nmp->nm_txthread = NULL;
 230         nmp->nm_txstate = NFSSVC_DONE;
 231         wakeup(&nmp->nm_txthread);
 232 }
 233
 234 void
 235 nfssvc_iod_stop1(struct nfsmount *nmp)
 236 {
 237         crit_enter();
 238         nmp->nm_txstate = NFSSVC_STOPPING;
 239         nmp->nm_rxstate = NFSSVC_STOPPING;
 240         crit_exit();
 241 }
 242
 243 void
 244 nfssvc_iod_stop2(struct nfsmount *nmp)
 245 {
 246         wakeup(&nmp->nm_txstate);
 247         while (nmp->nm_txthread)
 248                 tsleep(&nmp->nm_txthread, 0, "nfssttx", hz*2);
 249         wakeup(&nmp->nm_rxstate);
 250         while (nmp->nm_rxthread)
 251                 tsleep(&nmp->nm_rxthread, 0, "nfsstrx", hz*2);
 252 }
 253
 254 void
 255 nfssvc_iod_writer_wakeup(struct nfsmount *nmp)
 256 {
 257         if (nmp->nm_txstate == NFSSVC_WAITING) {
 258                 nmp->nm_txstate = NFSSVC_PENDING;
 259                 wakeup(&nmp->nm_txstate);
 260         }
 261 }
 262
 263 void
 264 nfssvc_iod_reader_wakeup(struct nfsmount *nmp)
 265 {
 266         if (nmp->nm_rxstate == NFSSVC_WAITING) {
 267                 nmp->nm_rxstate = NFSSVC_PENDING;
 268                 wakeup(&nmp->nm_rxstate);
 269         }
 270 }