lustre/llite/llite_capa.c

   1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
   2  * vim:expandtab:shiftwidth=8:tabstop=8:
   3  *
   4  * Copyright (C) 2004, 2005 Cluster File Systems, Inc.
   5  *
   6  * Author: Lai Siyao <lsy@clusterfs.com>
   7  *
   8  *   This file is part of Lustre, http://www.lustre.org.
   9  *
  10  *   Lustre is free software; you can redistribute it and/or
  11  *   modify it under the terms of version 2 of the GNU General Public
  12  *   License as published by the Free Software Foundation.
  13  *
  14  *   Lustre is distributed in the hope that it will be useful,
  15  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  *   GNU General Public License for more details.
  18  *
  19  *   You should have received a copy of the GNU General Public License
  20  *   along with Lustre; if not, write to the Free Software
  21  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  22  */
  23
  24 #define DEBUG_SUBSYSTEM S_LLITE
  25
  26 #include <linux/fs.h>
  27 #include <linux/version.h>
  28 #include <asm/uaccess.h>
  29 #include <linux/file.h>
  30 #include <linux/kmod.h>
  31
  32 #include <linux/lustre_lite.h>
  33 #include "llite_internal.h"
  34
  35 static struct list_head *ll_capa_list = &capa_list[CLIENT_CAPA];
  36 static struct ptlrpc_thread capa_thread;
  37
  38 static struct thread_ctl {
  39         struct completion ctl_starting;
  40         struct completion ctl_finishing;
  41 } ll_capa_ctl;
  42
  43 static inline int have_expired_capa(void)
  44 {
  45         struct obd_capa *ocapa;
  46         struct lustre_capa *capa;
  47         int expired = 0;
  48         unsigned long expiry;
  49         ENTRY;
  50
  51         spin_lock(&capa_lock);
  52         if (!list_empty(ll_capa_list)) {
  53                 ocapa = list_entry(ll_capa_list->next, struct obd_capa, c_list);
  54                 expired = __capa_is_to_expire(ocapa);
  55                 if (!expired) {
  56                         capa = &ocapa->c_capa;
  57                         expiry = expiry_to_jiffies(capa->lc_expiry -
  58                                                    capa_pre_expiry(capa));
  59                         if (time_before(expiry, ll_capa_timer.expires) ||
  60                             !timer_pending(&ll_capa_timer)) {
  61                                 mod_timer(&ll_capa_timer, expiry);
  62                                 CDEBUG(D_INFO,"ll_capa_timer new expiry: %lu\n",
  63                                        expiry);
  64                         }
  65                 }
  66         }
  67         spin_unlock(&capa_lock);
  68
  69         RETURN(expired);
  70 }
  71
  72 static int inline ll_capa_check_stop(void)
  73 {
  74         return (capa_thread.t_flags & SVC_STOPPING) ? 1: 0;
  75 }
  76
  77 static int ll_renew_capa(struct obd_capa *ocapa)
  78 {
  79         struct ptlrpc_request *req = NULL;
  80         /* no need to lock, no one else will touch it */
  81         struct inode *inode = ocapa->c_inode;
  82         struct obd_export *md_exp = ll_i2mdexp(inode);
  83         struct ll_inode_info *lli = ll_i2info(inode);
  84         __u64 valid = OBD_MD_CAPA;
  85         int rc;
  86         ENTRY;
  87
  88         if (capa_expired(&ocapa->c_capa))
  89                 RETURN(-ESTALE);
  90
  91         rc = md_getattr(md_exp, &lli->lli_id, valid, NULL, NULL, 0,
  92                         0, ocapa, &req);
  93         RETURN(rc);
  94 }
  95
  96 static int ll_capa_thread(void *arg)
  97 {
  98         struct thread_ctl *ctl = arg;
  99         unsigned long flags;
 100         int rc;
 101         ENTRY;
 102
 103         {
 104                 char name[sizeof(current->comm)];
 105                 snprintf(name, sizeof(name) - 1, "ll_capa");
 106                 kportal_daemonize(name);
 107         }
 108
 109         SIGNAL_MASK_LOCK(current, flags);
 110         sigfillset(&current->blocked);
 111         RECALC_SIGPENDING;
 112         SIGNAL_MASK_UNLOCK(current, flags);
 113
 114         /*
 115          * letting starting function know, that we are ready and control may be
 116          * returned.
 117          */
 118         capa_thread.t_flags = SVC_RUNNING;
 119         complete(&ctl->ctl_starting);
 120
 121         while (1) {
 122                 struct l_wait_info lwi = { 0 };
 123                 struct obd_capa *ocapa, tcapa, *tmp, *next = NULL;
 124                 unsigned long expiry, sleep = CAPA_PRE_EXPIRY;
 125                 struct inode *inode;
 126
 127                 l_wait_event(capa_thread.t_ctl_waitq,
 128                              (have_expired_capa() || ll_capa_check_stop()),
 129                              &lwi);
 130
 131                 if (ll_capa_check_stop())
 132                         break;
 133
 134                 spin_lock(&capa_lock);
 135                 list_for_each_entry_safe(ocapa, tmp, ll_capa_list, c_list) {
 136                         if (ocapa->c_capa.lc_flags & CAPA_FL_SHORT)
 137                                 sleep = CAPA_PRE_EXPIRY_SHORT;
 138
 139                         if (ocapa->c_capa.lc_op == CAPA_TRUNC)
 140                                 continue;
 141
 142                         if (__capa_is_to_expire(ocapa)) {
 143                                 inode = igrab(ocapa->c_inode);
 144                                 if (inode == NULL)
 145                                         continue;
 146
 147                                 tcapa = *ocapa;
 148                                 spin_unlock(&capa_lock);
 149
 150                                 rc = ll_renew_capa(&tcapa);
 151                                 iput(inode);
 152
 153                                 if (rc)
 154                                         capa_put(ocapa);
 155
 156                                 spin_lock(&capa_lock);
 157                         } else {
 158                                 next = ocapa;
 159                                 break;
 160                         }
 161                 }
 162
 163                 if (next) {
 164                         struct lustre_capa *capa = &next->c_capa;
 165
 166                         expiry = expiry_to_jiffies(capa->lc_expiry -
 167                                                    capa_pre_expiry(capa));
 168                         if (time_before(expiry, ll_capa_timer.expires) ||
 169                             !timer_pending(&ll_capa_timer)) {
 170                                 mod_timer(&ll_capa_timer, expiry);
 171                                 CDEBUG(D_INFO,"ll_capa_timer new expiry: %lu\n",
 172                                        expiry);
 173                         }
 174                 }
 175                 spin_unlock(&capa_lock);
 176
 177                 /* wait ll_renew_capa finish */
 178                 set_current_state(TASK_INTERRUPTIBLE);
 179                 schedule_timeout(sleep * HZ);
 180         }
 181
 182         capa_thread.t_flags = SVC_STOPPED;
 183
 184         /* this is SMP-safe way to finish thread. */
 185         complete_and_exit(&ctl->ctl_finishing, 0);
 186         EXIT;
 187 }
 188
 189 /* just wake up, others are handled by ll_capa_thread */
 190 void ll_capa_timer_callback(unsigned long unused)
 191 {
 192         ENTRY;
 193         wake_up(&capa_thread.t_ctl_waitq);
 194         EXIT;
 195 }
 196
 197 int ll_capa_thread_start(void)
 198 {
 199         int rc;
 200         ENTRY;
 201
 202         LASSERT(capa_thread.t_flags == 0);
 203         init_completion(&ll_capa_ctl.ctl_starting);
 204         init_completion(&ll_capa_ctl.ctl_finishing);
 205         init_waitqueue_head(&capa_thread.t_ctl_waitq);
 206
 207         rc = kernel_thread(ll_capa_thread, &ll_capa_ctl,
 208                            (CLONE_VM | CLONE_FILES));
 209         if (rc < 0) {
 210                 CERROR("cannot start expired capa thread, "
 211                        "err = %d\n", rc);
 212                 RETURN(rc);
 213         }
 214         wait_for_completion(&ll_capa_ctl.ctl_starting);
 215         LASSERT(capa_thread.t_flags == SVC_RUNNING);
 216         RETURN(0);
 217 }
 218
 219 void ll_capa_thread_stop(void)
 220 {
 221         ENTRY;
 222
 223         capa_thread.t_flags = SVC_STOPPING;
 224         wake_up(&capa_thread.t_ctl_waitq);
 225         wait_for_completion(&ll_capa_ctl.ctl_finishing);
 226         LASSERT(capa_thread.t_flags == SVC_STOPPED);
 227         capa_thread.t_flags = 0;
 228
 229         EXIT;
 230 }
 231
 232 int ll_set_capa(struct inode *inode, struct lookup_intent *it,
 233                 struct obd_client_handle *och)
 234 {
 235         struct ptlrpc_request *req = LUSTRE_IT(it)->it_data;
 236         struct mds_body *body;
 237         struct lustre_capa *capa;
 238         struct obd_capa *ocapa;
 239         struct ll_inode_info *lli = ll_i2info(inode);
 240         unsigned long expiry;
 241
 242         if (!S_ISREG(inode->i_mode))
 243                 return 0;
 244
 245         /* GNS code path will have no req */
 246         if (!req)
 247                 return 0;
 248
 249         body = lustre_msg_buf(req->rq_repmsg, 1, sizeof (*body));
 250         LASSERT(body != NULL);          /* reply already checked out */
 251         LASSERT_REPSWABBED(req, 1);     /* and swabbed down */
 252
 253         if (!(body->valid & OBD_MD_CAPA))
 254                 return 0;
 255
 256         ENTRY;
 257
 258         capa = lustre_msg_buf(req->rq_repmsg, 7, sizeof (*capa));
 259         LASSERT(capa != NULL);          /* reply already checked out */
 260         LASSERT_REPSWABBED(req, 7);     /* and swabbed down */
 261
 262         ocapa = capa_renew(capa, CLIENT_CAPA);
 263         if (!ocapa)
 264                 RETURN(-ENOMEM);
 265
 266         spin_lock(&capa_lock);
 267         ocapa->c_inode = inode;
 268         ocapa->c_handle = och->och_fh;
 269         spin_unlock(&capa_lock);
 270
 271         spin_lock(&lli->lli_lock);
 272         /* in case it was linked to lli_capas already */
 273         if (list_empty(&ocapa->c_lli_list))
 274                 list_add(&ocapa->c_lli_list, &lli->lli_capas);
 275         spin_unlock(&lli->lli_lock);
 276
 277         expiry = expiry_to_jiffies(capa->lc_expiry - capa_pre_expiry(capa));
 278
 279         spin_lock(&capa_lock);
 280         if (time_before(expiry, ll_capa_timer.expires) ||
 281             !timer_pending(&ll_capa_timer)) {
 282                 mod_timer(&ll_capa_timer, expiry);
 283                 CDEBUG(D_INFO, "ll_capa_timer new expiry: %lu\n", expiry);
 284         }
 285         spin_unlock(&capa_lock);
 286
 287         RETURN(0);
 288 }
 289
 290 int ll_set_trunc_capa(struct ptlrpc_request *req, int offset, struct inode *inode)
 291 {
 292         struct mds_body *body;
 293         struct obd_capa *ocapa;
 294         struct lustre_capa *capa;
 295         struct ll_inode_info *lli = ll_i2info(inode);
 296
 297         body = lustre_msg_buf(req->rq_repmsg, offset, sizeof(*body));
 298         if (!body)
 299                 return -ENOMEM;
 300
 301         if (!(body->valid & OBD_MD_CAPA))
 302                 return 0;
 303
 304         ENTRY;
 305         capa = (struct lustre_capa *)lustre_swab_repbuf(req, offset + 1,
 306                                         sizeof(*capa), lustre_swab_lustre_capa);
 307         if (!capa)
 308                 RETURN(-ENOMEM);
 309
 310         ocapa = capa_renew(capa, CLIENT_CAPA);
 311         if (!ocapa)
 312                 RETURN(-ENOMEM);
 313
 314         spin_lock(&lli->lli_lock);
 315         /* in case it was linked to lli_capas already */
 316         if (list_empty(&ocapa->c_lli_list))
 317                 list_add(&ocapa->c_lli_list, &lli->lli_capas);
 318         spin_unlock(&lli->lli_lock);
 319
 320         RETURN(0);
 321 }
 322
 323 struct obd_capa *ll_get_capa(struct inode *inode, uid_t uid, int op)
 324 {
 325         struct ll_inode_info *lli = ll_i2info(inode);
 326         struct obd_capa *ocapa, *tmp;
 327         ENTRY;
 328
 329         list_for_each_entry_safe(ocapa, tmp, &lli->lli_capas, c_lli_list) {
 330                 if (ocapa->c_capa.lc_ruid != uid)
 331                         continue;
 332                 if (ocapa->c_capa.lc_op != op)
 333                         continue;
 334
 335                 RETURN(ocapa);
 336         }
 337
 338         RETURN(NULL);
 339 }