linux/drivers/staging/lustre/lustre/include/lustre_lib.h
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   1/*
   2 * GPL HEADER START
   3 *
   4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   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 version 2 only,
   8 * as published by the Free Software Foundation.
   9 *
  10 * This program is distributed in the hope that it will be useful, but
  11 * WITHOUT ANY WARRANTY; without even the implied warranty of
  12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13 * General Public License version 2 for more details (a copy is included
  14 * in the LICENSE file that accompanied this code).
  15 *
  16 * You should have received a copy of the GNU General Public License
  17 * version 2 along with this program; If not, see
  18 * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
  19 *
  20 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  21 * CA 95054 USA or visit www.sun.com if you need additional information or
  22 * have any questions.
  23 *
  24 * GPL HEADER END
  25 */
  26/*
  27 * Copyright (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved.
  28 * Use is subject to license terms.
  29 *
  30 * Copyright (c) 2011, 2012, Intel Corporation.
  31 */
  32/*
  33 * This file is part of Lustre, http://www.lustre.org/
  34 * Lustre is a trademark of Sun Microsystems, Inc.
  35 *
  36 * lustre/include/lustre_lib.h
  37 *
  38 * Basic Lustre library routines.
  39 */
  40
  41#ifndef _LUSTRE_LIB_H
  42#define _LUSTRE_LIB_H
  43
  44/** \defgroup lib lib
  45 *
  46 * @{
  47 */
  48
  49#include <linux/sched.h>
  50#include <linux/signal.h>
  51#include <linux/types.h>
  52#include "../../include/linux/libcfs/libcfs.h"
  53#include "lustre/lustre_idl.h"
  54#include "lustre_ver.h"
  55#include "lustre_cfg.h"
  56
  57/* target.c */
  58struct kstatfs;
  59struct ptlrpc_request;
  60struct obd_export;
  61struct lu_target;
  62struct l_wait_info;
  63#include "lustre_ha.h"
  64#include "lustre_net.h"
  65
  66#define LI_POISON 0x5a5a5a5a
  67#if BITS_PER_LONG > 32
  68# define LL_POISON 0x5a5a5a5a5a5a5a5aL
  69#else
  70# define LL_POISON 0x5a5a5a5aL
  71#endif
  72#define LP_POISON ((void *)LL_POISON)
  73
  74int target_pack_pool_reply(struct ptlrpc_request *req);
  75int do_set_info_async(struct obd_import *imp,
  76                      int opcode, int version,
  77                      u32 keylen, void *key,
  78                      u32 vallen, void *val,
  79                      struct ptlrpc_request_set *set);
  80
  81#define OBD_RECOVERY_MAX_TIME (obd_timeout * 18) /* b13079 */
  82#define OBD_MAX_IOCTL_BUFFER CONFIG_LUSTRE_OBD_MAX_IOCTL_BUFFER
  83
  84void target_send_reply(struct ptlrpc_request *req, int rc, int fail_id);
  85
  86/* client.c */
  87
  88int client_sanobd_setup(struct obd_device *obddev, struct lustre_cfg *lcfg);
  89struct client_obd *client_conn2cli(struct lustre_handle *conn);
  90
  91struct md_open_data;
  92struct obd_client_handle {
  93        struct lustre_handle     och_fh;
  94        struct lu_fid            och_fid;
  95        struct md_open_data     *och_mod;
  96        struct lustre_handle     och_lease_handle; /* open lock for lease */
  97        __u32                    och_magic;
  98        fmode_t                  och_flags;
  99};
 100
 101#define OBD_CLIENT_HANDLE_MAGIC 0xd15ea5ed
 102
 103/* statfs_pack.c */
 104void statfs_unpack(struct kstatfs *sfs, struct obd_statfs *osfs);
 105
 106/*
 107 * For md echo client
 108 */
 109enum md_echo_cmd {
 110        ECHO_MD_CREATE       = 1, /* Open/Create file on MDT */
 111        ECHO_MD_MKDIR   = 2, /* Mkdir on MDT */
 112        ECHO_MD_DESTROY      = 3, /* Unlink file on MDT */
 113        ECHO_MD_RMDIR   = 4, /* Rmdir on MDT */
 114        ECHO_MD_LOOKUP       = 5, /* Lookup on MDT */
 115        ECHO_MD_GETATTR      = 6, /* Getattr on MDT */
 116        ECHO_MD_SETATTR      = 7, /* Setattr on MDT */
 117        ECHO_MD_ALLOC_FID    = 8, /* Get FIDs from MDT */
 118};
 119
 120/*
 121 *   OBD IOCTLS
 122 */
 123#define OBD_IOCTL_VERSION 0x00010004
 124
 125struct obd_ioctl_data {
 126        __u32 ioc_len;
 127        __u32 ioc_version;
 128
 129        union {
 130                __u64 ioc_cookie;
 131                __u64 ioc_u64_1;
 132        };
 133        union {
 134                __u32 ioc_conn1;
 135                __u32 ioc_u32_1;
 136        };
 137        union {
 138                __u32 ioc_conn2;
 139                __u32 ioc_u32_2;
 140        };
 141
 142        struct obdo ioc_obdo1;
 143        struct obdo ioc_obdo2;
 144
 145        u64      ioc_count;
 146        u64      ioc_offset;
 147        __u32    ioc_dev;
 148        __u32    ioc_command;
 149
 150        __u64 ioc_nid;
 151        __u32 ioc_nal;
 152        __u32 ioc_type;
 153
 154        /* buffers the kernel will treat as user pointers */
 155        __u32  ioc_plen1;
 156        void __user *ioc_pbuf1;
 157        __u32  ioc_plen2;
 158        void __user *ioc_pbuf2;
 159
 160        /* inline buffers for various arguments */
 161        __u32  ioc_inllen1;
 162        char  *ioc_inlbuf1;
 163        __u32  ioc_inllen2;
 164        char  *ioc_inlbuf2;
 165        __u32  ioc_inllen3;
 166        char  *ioc_inlbuf3;
 167        __u32  ioc_inllen4;
 168        char  *ioc_inlbuf4;
 169
 170        char    ioc_bulk[0];
 171};
 172
 173struct obd_ioctl_hdr {
 174        __u32 ioc_len;
 175        __u32 ioc_version;
 176};
 177
 178static inline int obd_ioctl_packlen(struct obd_ioctl_data *data)
 179{
 180        int len = cfs_size_round(sizeof(struct obd_ioctl_data));
 181
 182        len += cfs_size_round(data->ioc_inllen1);
 183        len += cfs_size_round(data->ioc_inllen2);
 184        len += cfs_size_round(data->ioc_inllen3);
 185        len += cfs_size_round(data->ioc_inllen4);
 186        return len;
 187}
 188
 189static inline int obd_ioctl_is_invalid(struct obd_ioctl_data *data)
 190{
 191        if (data->ioc_len > OBD_MAX_IOCTL_BUFFER) {
 192                CERROR("OBD ioctl: ioc_len larger than %d\n",
 193                       OBD_MAX_IOCTL_BUFFER);
 194                return 1;
 195        }
 196        if (data->ioc_inllen1 > OBD_MAX_IOCTL_BUFFER) {
 197                CERROR("OBD ioctl: ioc_inllen1 larger than ioc_len\n");
 198                return 1;
 199        }
 200        if (data->ioc_inllen2 > OBD_MAX_IOCTL_BUFFER) {
 201                CERROR("OBD ioctl: ioc_inllen2 larger than ioc_len\n");
 202                return 1;
 203        }
 204        if (data->ioc_inllen3 > OBD_MAX_IOCTL_BUFFER) {
 205                CERROR("OBD ioctl: ioc_inllen3 larger than ioc_len\n");
 206                return 1;
 207        }
 208        if (data->ioc_inllen4 > OBD_MAX_IOCTL_BUFFER) {
 209                CERROR("OBD ioctl: ioc_inllen4 larger than ioc_len\n");
 210                return 1;
 211        }
 212        if (data->ioc_inlbuf1 && !data->ioc_inllen1) {
 213                CERROR("OBD ioctl: inlbuf1 pointer but 0 length\n");
 214                return 1;
 215        }
 216        if (data->ioc_inlbuf2 && !data->ioc_inllen2) {
 217                CERROR("OBD ioctl: inlbuf2 pointer but 0 length\n");
 218                return 1;
 219        }
 220        if (data->ioc_inlbuf3 && !data->ioc_inllen3) {
 221                CERROR("OBD ioctl: inlbuf3 pointer but 0 length\n");
 222                return 1;
 223        }
 224        if (data->ioc_inlbuf4 && !data->ioc_inllen4) {
 225                CERROR("OBD ioctl: inlbuf4 pointer but 0 length\n");
 226                return 1;
 227        }
 228        if (data->ioc_pbuf1 && !data->ioc_plen1) {
 229                CERROR("OBD ioctl: pbuf1 pointer but 0 length\n");
 230                return 1;
 231        }
 232        if (data->ioc_pbuf2 && !data->ioc_plen2) {
 233                CERROR("OBD ioctl: pbuf2 pointer but 0 length\n");
 234                return 1;
 235        }
 236        if (data->ioc_plen1 && !data->ioc_pbuf1) {
 237                CERROR("OBD ioctl: plen1 set but NULL pointer\n");
 238                return 1;
 239        }
 240        if (data->ioc_plen2 && !data->ioc_pbuf2) {
 241                CERROR("OBD ioctl: plen2 set but NULL pointer\n");
 242                return 1;
 243        }
 244        if (obd_ioctl_packlen(data) > data->ioc_len) {
 245                CERROR("OBD ioctl: packlen exceeds ioc_len (%d > %d)\n",
 246                       obd_ioctl_packlen(data), data->ioc_len);
 247                return 1;
 248        }
 249        return 0;
 250}
 251
 252#include "obd_support.h"
 253
 254/* function defined in lustre/obdclass/<platform>/<platform>-module.c */
 255int obd_ioctl_getdata(char **buf, int *len, void __user *arg);
 256int obd_ioctl_popdata(void __user *arg, void *data, int len);
 257
 258static inline void obd_ioctl_freedata(char *buf, int len)
 259{
 260        kvfree(buf);
 261        return;
 262}
 263
 264/*
 265 * BSD ioctl description:
 266 * #define IOC_V1       _IOR(g, n1, long)
 267 * #define IOC_V2       _IOW(g, n2, long)
 268 *
 269 * ioctl(f, IOC_V1, arg);
 270 * arg will be treated as a long value,
 271 *
 272 * ioctl(f, IOC_V2, arg)
 273 * arg will be treated as a pointer, bsd will call
 274 * copyin(buf, arg, sizeof(long))
 275 *
 276 * To make BSD ioctl handles argument correctly and simplely,
 277 * we change _IOR to _IOWR so BSD will copyin obd_ioctl_data
 278 * for us. Does this change affect Linux?  (XXX Liang)
 279 */
 280#define OBD_IOC_DATA_TYPE long
 281
 282#define OBD_IOC_CREATE           _IOWR('f', 101, OBD_IOC_DATA_TYPE)
 283#define OBD_IOC_DESTROY         _IOW ('f', 104, OBD_IOC_DATA_TYPE)
 284#define OBD_IOC_PREALLOCATE         _IOWR('f', 105, OBD_IOC_DATA_TYPE)
 285
 286#define OBD_IOC_SETATTR         _IOW ('f', 107, OBD_IOC_DATA_TYPE)
 287#define OBD_IOC_GETATTR         _IOWR ('f', 108, OBD_IOC_DATA_TYPE)
 288#define OBD_IOC_READ               _IOWR('f', 109, OBD_IOC_DATA_TYPE)
 289#define OBD_IOC_WRITE             _IOWR('f', 110, OBD_IOC_DATA_TYPE)
 290
 291#define OBD_IOC_STATFS           _IOWR('f', 113, OBD_IOC_DATA_TYPE)
 292#define OBD_IOC_SYNC               _IOW ('f', 114, OBD_IOC_DATA_TYPE)
 293#define OBD_IOC_READ2             _IOWR('f', 115, OBD_IOC_DATA_TYPE)
 294#define OBD_IOC_FORMAT           _IOWR('f', 116, OBD_IOC_DATA_TYPE)
 295#define OBD_IOC_PARTITION             _IOWR('f', 117, OBD_IOC_DATA_TYPE)
 296#define OBD_IOC_COPY               _IOWR('f', 120, OBD_IOC_DATA_TYPE)
 297#define OBD_IOC_MIGR               _IOWR('f', 121, OBD_IOC_DATA_TYPE)
 298#define OBD_IOC_PUNCH             _IOWR('f', 122, OBD_IOC_DATA_TYPE)
 299
 300#define OBD_IOC_MODULE_DEBUG       _IOWR('f', 124, OBD_IOC_DATA_TYPE)
 301#define OBD_IOC_BRW_READ               _IOWR('f', 125, OBD_IOC_DATA_TYPE)
 302#define OBD_IOC_BRW_WRITE             _IOWR('f', 126, OBD_IOC_DATA_TYPE)
 303#define OBD_IOC_NAME2DEV               _IOWR('f', 127, OBD_IOC_DATA_TYPE)
 304#define OBD_IOC_UUID2DEV               _IOWR('f', 130, OBD_IOC_DATA_TYPE)
 305
 306#define OBD_IOC_GETNAME         _IOWR('f', 131, OBD_IOC_DATA_TYPE)
 307#define OBD_IOC_GETMDNAME             _IOR('f', 131, char[MAX_OBD_NAME])
 308#define OBD_IOC_GETDTNAME              OBD_IOC_GETNAME
 309
 310#define OBD_IOC_LOV_GET_CONFIG   _IOWR('f', 132, OBD_IOC_DATA_TYPE)
 311#define OBD_IOC_CLIENT_RECOVER   _IOW ('f', 133, OBD_IOC_DATA_TYPE)
 312#define OBD_IOC_PING_TARGET         _IOW ('f', 136, OBD_IOC_DATA_TYPE)
 313
 314#define OBD_IOC_DEC_FS_USE_COUNT       _IO  ('f', 139)
 315#define OBD_IOC_NO_TRANSNO           _IOW ('f', 140, OBD_IOC_DATA_TYPE)
 316#define OBD_IOC_SET_READONLY       _IOW ('f', 141, OBD_IOC_DATA_TYPE)
 317#define OBD_IOC_ABORT_RECOVERY   _IOR ('f', 142, OBD_IOC_DATA_TYPE)
 318
 319#define OBD_IOC_ROOT_SQUASH         _IOWR('f', 143, OBD_IOC_DATA_TYPE)
 320
 321#define OBD_GET_VERSION         _IOWR ('f', 144, OBD_IOC_DATA_TYPE)
 322
 323#define OBD_IOC_GSS_SUPPORT         _IOWR('f', 145, OBD_IOC_DATA_TYPE)
 324
 325#define OBD_IOC_CLOSE_UUID           _IOWR ('f', 147, OBD_IOC_DATA_TYPE)
 326
 327#define OBD_IOC_CHANGELOG_SEND   _IOW ('f', 148, OBD_IOC_DATA_TYPE)
 328#define OBD_IOC_GETDEVICE             _IOWR ('f', 149, OBD_IOC_DATA_TYPE)
 329#define OBD_IOC_FID2PATH               _IOWR ('f', 150, OBD_IOC_DATA_TYPE)
 330/* see also <lustre/lustre_user.h> for ioctls 151-153 */
 331/* OBD_IOC_LOV_SETSTRIPE: See also LL_IOC_LOV_SETSTRIPE */
 332#define OBD_IOC_LOV_SETSTRIPE     _IOW ('f', 154, OBD_IOC_DATA_TYPE)
 333/* OBD_IOC_LOV_GETSTRIPE: See also LL_IOC_LOV_GETSTRIPE */
 334#define OBD_IOC_LOV_GETSTRIPE     _IOW ('f', 155, OBD_IOC_DATA_TYPE)
 335/* OBD_IOC_LOV_SETEA: See also LL_IOC_LOV_SETEA */
 336#define OBD_IOC_LOV_SETEA             _IOW ('f', 156, OBD_IOC_DATA_TYPE)
 337/* see <lustre/lustre_user.h> for ioctls 157-159 */
 338/* OBD_IOC_QUOTACHECK: See also LL_IOC_QUOTACHECK */
 339#define OBD_IOC_QUOTACHECK           _IOW ('f', 160, int)
 340/* OBD_IOC_POLL_QUOTACHECK: See also LL_IOC_POLL_QUOTACHECK */
 341#define OBD_IOC_POLL_QUOTACHECK _IOR ('f', 161, struct if_quotacheck *)
 342/* OBD_IOC_QUOTACTL: See also LL_IOC_QUOTACTL */
 343#define OBD_IOC_QUOTACTL               _IOWR('f', 162, struct if_quotactl)
 344/* see  also <lustre/lustre_user.h> for ioctls 163-176 */
 345#define OBD_IOC_CHANGELOG_REG     _IOW ('f', 177, struct obd_ioctl_data)
 346#define OBD_IOC_CHANGELOG_DEREG _IOW ('f', 178, struct obd_ioctl_data)
 347#define OBD_IOC_CHANGELOG_CLEAR _IOW ('f', 179, struct obd_ioctl_data)
 348#define OBD_IOC_RECORD           _IOWR('f', 180, OBD_IOC_DATA_TYPE)
 349#define OBD_IOC_ENDRECORD             _IOWR('f', 181, OBD_IOC_DATA_TYPE)
 350#define OBD_IOC_PARSE             _IOWR('f', 182, OBD_IOC_DATA_TYPE)
 351#define OBD_IOC_DORECORD               _IOWR('f', 183, OBD_IOC_DATA_TYPE)
 352#define OBD_IOC_PROCESS_CFG         _IOWR('f', 184, OBD_IOC_DATA_TYPE)
 353#define OBD_IOC_DUMP_LOG               _IOWR('f', 185, OBD_IOC_DATA_TYPE)
 354#define OBD_IOC_CLEAR_LOG             _IOWR('f', 186, OBD_IOC_DATA_TYPE)
 355#define OBD_IOC_PARAM             _IOW ('f', 187, OBD_IOC_DATA_TYPE)
 356#define OBD_IOC_POOL               _IOWR('f', 188, OBD_IOC_DATA_TYPE)
 357#define OBD_IOC_REPLACE_NIDS       _IOWR('f', 189, OBD_IOC_DATA_TYPE)
 358
 359#define OBD_IOC_CATLOGLIST           _IOWR('f', 190, OBD_IOC_DATA_TYPE)
 360#define OBD_IOC_LLOG_INFO             _IOWR('f', 191, OBD_IOC_DATA_TYPE)
 361#define OBD_IOC_LLOG_PRINT           _IOWR('f', 192, OBD_IOC_DATA_TYPE)
 362#define OBD_IOC_LLOG_CANCEL         _IOWR('f', 193, OBD_IOC_DATA_TYPE)
 363#define OBD_IOC_LLOG_REMOVE         _IOWR('f', 194, OBD_IOC_DATA_TYPE)
 364#define OBD_IOC_LLOG_CHECK           _IOWR('f', 195, OBD_IOC_DATA_TYPE)
 365/* OBD_IOC_LLOG_CATINFO is deprecated */
 366#define OBD_IOC_LLOG_CATINFO       _IOWR('f', 196, OBD_IOC_DATA_TYPE)
 367
 368/*      #define ECHO_IOC_GET_STRIPE    _IOWR('f', 200, OBD_IOC_DATA_TYPE) */
 369/*      #define ECHO_IOC_SET_STRIPE    _IOWR('f', 201, OBD_IOC_DATA_TYPE) */
 370/*      #define ECHO_IOC_ENQUEUE       _IOWR('f', 202, OBD_IOC_DATA_TYPE) */
 371/*      #define ECHO_IOC_CANCEL        _IOWR('f', 203, OBD_IOC_DATA_TYPE) */
 372
 373#define OBD_IOC_GET_OBJ_VERSION _IOR('f', 210, OBD_IOC_DATA_TYPE)
 374
 375/* <lustre/lustre_user.h> defines ioctl number 218-219 */
 376#define OBD_IOC_GET_MNTOPT           _IOW('f', 220, mntopt_t)
 377
 378#define OBD_IOC_ECHO_MD         _IOR('f', 221, struct obd_ioctl_data)
 379#define OBD_IOC_ECHO_ALLOC_SEQ   _IOWR('f', 222, struct obd_ioctl_data)
 380
 381#define OBD_IOC_START_LFSCK            _IOWR('f', 230, OBD_IOC_DATA_TYPE)
 382#define OBD_IOC_STOP_LFSCK             _IOW('f', 231, OBD_IOC_DATA_TYPE)
 383#define OBD_IOC_PAUSE_LFSCK            _IOW('f', 232, OBD_IOC_DATA_TYPE)
 384
 385/* XXX _IOWR('f', 250, long) has been defined in
 386 * libcfs/include/libcfs/libcfs_private.h for debug, don't use it
 387 */
 388
 389/* Until such time as we get_info the per-stripe maximum from the OST,
 390 * we define this to be 2T - 4k, which is the ext3 maxbytes.
 391 */
 392#define LUSTRE_STRIPE_MAXBYTES 0x1fffffff000ULL
 393
 394/* Special values for remove LOV EA from disk */
 395#define LOVEA_DELETE_VALUES(size, count, offset) (size == 0 && count == 0 && \
 396                                                 offset == (typeof(offset))(-1))
 397
 398/* #define POISON_BULK 0 */
 399
 400/*
 401 * l_wait_event is a flexible sleeping function, permitting simple caller
 402 * configuration of interrupt and timeout sensitivity along with actions to
 403 * be performed in the event of either exception.
 404 *
 405 * The first form of usage looks like this:
 406 *
 407 * struct l_wait_info lwi = LWI_TIMEOUT_INTR(timeout, timeout_handler,
 408 *                                         intr_handler, callback_data);
 409 * rc = l_wait_event(waitq, condition, &lwi);
 410 *
 411 * l_wait_event() makes the current process wait on 'waitq' until 'condition'
 412 * is TRUE or a "killable" signal (SIGTERM, SIKGILL, SIGINT) is pending.  It
 413 * returns 0 to signify 'condition' is TRUE, but if a signal wakes it before
 414 * 'condition' becomes true, it optionally calls the specified 'intr_handler'
 415 * if not NULL, and returns -EINTR.
 416 *
 417 * If a non-zero timeout is specified, signals are ignored until the timeout
 418 * has expired.  At this time, if 'timeout_handler' is not NULL it is called.
 419 * If it returns FALSE l_wait_event() continues to wait as described above with
 420 * signals enabled.  Otherwise it returns -ETIMEDOUT.
 421 *
 422 * LWI_INTR(intr_handler, callback_data) is shorthand for
 423 * LWI_TIMEOUT_INTR(0, NULL, intr_handler, callback_data)
 424 *
 425 * The second form of usage looks like this:
 426 *
 427 * struct l_wait_info lwi = LWI_TIMEOUT(timeout, timeout_handler);
 428 * rc = l_wait_event(waitq, condition, &lwi);
 429 *
 430 * This form is the same as the first except that it COMPLETELY IGNORES
 431 * SIGNALS.  The caller must therefore beware that if 'timeout' is zero, or if
 432 * 'timeout_handler' is not NULL and returns FALSE, then the ONLY thing that
 433 * can unblock the current process is 'condition' becoming TRUE.
 434 *
 435 * Another form of usage is:
 436 * struct l_wait_info lwi = LWI_TIMEOUT_INTERVAL(timeout, interval,
 437 *                                             timeout_handler);
 438 * rc = l_wait_event(waitq, condition, &lwi);
 439 * This is the same as previous case, but condition is checked once every
 440 * 'interval' jiffies (if non-zero).
 441 *
 442 * Subtle synchronization point: this macro does *not* necessary takes
 443 * wait-queue spin-lock before returning, and, hence, following idiom is safe
 444 * ONLY when caller provides some external locking:
 445 *
 446 *           Thread1                        Thread2
 447 *
 448 *   l_wait_event(&obj->wq, ....);                                     (1)
 449 *
 450 *                                  wake_up(&obj->wq):           (2)
 451 *                                       spin_lock(&q->lock);     (2.1)
 452 *                                       __wake_up_common(q, ...);     (2.2)
 453 *                                       spin_unlock(&q->lock, flags); (2.3)
 454 *
 455 *   kfree(obj);                                                  (3)
 456 *
 457 * As l_wait_event() may "short-cut" execution and return without taking
 458 * wait-queue spin-lock, some additional synchronization is necessary to
 459 * guarantee that step (3) can begin only after (2.3) finishes.
 460 *
 461 * XXX nikita: some ptlrpc daemon threads have races of that sort.
 462 *
 463 */
 464static inline int back_to_sleep(void *arg)
 465{
 466        return 0;
 467}
 468
 469#define LWI_ON_SIGNAL_NOOP ((void (*)(void *))(-1))
 470
 471struct l_wait_info {
 472        long lwi_timeout;
 473        long lwi_interval;
 474        int         lwi_allow_intr;
 475        int  (*lwi_on_timeout)(void *);
 476        void (*lwi_on_signal)(void *);
 477        void  *lwi_cb_data;
 478};
 479
 480/* NB: LWI_TIMEOUT ignores signals completely */
 481#define LWI_TIMEOUT(time, cb, data)          \
 482((struct l_wait_info) {                  \
 483        .lwi_timeout    = time,          \
 484        .lwi_on_timeout = cb,              \
 485        .lwi_cb_data    = data,          \
 486        .lwi_interval   = 0,                \
 487        .lwi_allow_intr = 0                  \
 488})
 489
 490#define LWI_TIMEOUT_INTERVAL(time, interval, cb, data)  \
 491((struct l_wait_info) {                          \
 492        .lwi_timeout    = time,                  \
 493        .lwi_on_timeout = cb,                      \
 494        .lwi_cb_data    = data,                  \
 495        .lwi_interval   = interval,                  \
 496        .lwi_allow_intr = 0                          \
 497})
 498
 499#define LWI_TIMEOUT_INTR(time, time_cb, sig_cb, data)   \
 500((struct l_wait_info) {                          \
 501        .lwi_timeout    = time,                  \
 502        .lwi_on_timeout = time_cb,                    \
 503        .lwi_on_signal  = sig_cb,                      \
 504        .lwi_cb_data    = data,                  \
 505        .lwi_interval   = 0,                        \
 506        .lwi_allow_intr = 0                          \
 507})
 508
 509#define LWI_TIMEOUT_INTR_ALL(time, time_cb, sig_cb, data)       \
 510((struct l_wait_info) {                                  \
 511        .lwi_timeout    = time,                          \
 512        .lwi_on_timeout = time_cb,                            \
 513        .lwi_on_signal  = sig_cb,                              \
 514        .lwi_cb_data    = data,                          \
 515        .lwi_interval   = 0,                                \
 516        .lwi_allow_intr = 1                                  \
 517})
 518
 519#define LWI_INTR(cb, data)  LWI_TIMEOUT_INTR(0, NULL, cb, data)
 520
 521#define LUSTRE_FATAL_SIGS (sigmask(SIGKILL) | sigmask(SIGINT) |         \
 522                           sigmask(SIGTERM) | sigmask(SIGQUIT) |        \
 523                           sigmask(SIGALRM))
 524
 525/*
 526 * wait for @condition to become true, but no longer than timeout, specified
 527 * by @info.
 528 */
 529#define __l_wait_event(wq, condition, info, ret, l_add_wait)               \
 530do {                                                                       \
 531        wait_queue_t __wait;                                             \
 532        long __timeout = info->lwi_timeout;                       \
 533        sigset_t   __blocked;                                         \
 534        int   __allow_intr = info->lwi_allow_intr;                           \
 535                                                                               \
 536        ret = 0;                                                               \
 537        if (condition)                                                   \
 538                break;                                                   \
 539                                                                               \
 540        init_waitqueue_entry(&__wait, current);                                     \
 541        l_add_wait(&wq, &__wait);                                             \
 542                                                                               \
 543        /* Block all signals (just the non-fatal ones if no timeout). */       \
 544        if (info->lwi_on_signal && (__timeout == 0 || __allow_intr))   \
 545                __blocked = cfs_block_sigsinv(LUSTRE_FATAL_SIGS);             \
 546        else                                                               \
 547                __blocked = cfs_block_sigsinv(0);                             \
 548                                                                               \
 549        for (;;) {                                                           \
 550                if (condition)                                           \
 551                        break;                                           \
 552                                                                               \
 553                set_current_state(TASK_INTERRUPTIBLE);                         \
 554                                                                               \
 555                if (__timeout == 0) {                                     \
 556                        schedule();                                            \
 557                } else {                                                       \
 558                        long interval = info->lwi_interval ?      \
 559                                             min_t(long,             \
 560                                                 info->lwi_interval, __timeout) : \
 561                                             __timeout;                 \
 562                        long remaining = schedule_timeout(interval);\
 563                        __timeout = cfs_time_sub(__timeout,                 \
 564                                            cfs_time_sub(interval, remaining));\
 565                        if (__timeout == 0) {                             \
 566                                if (!info->lwi_on_timeout ||                  \
 567                                    info->lwi_on_timeout(info->lwi_cb_data)) { \
 568                                        ret = -ETIMEDOUT;                     \
 569                                        break;                           \
 570                                }                                             \
 571                                /* Take signals after the timeout expires. */  \
 572                                if (info->lwi_on_signal)                       \
 573                                    (void)cfs_block_sigsinv(LUSTRE_FATAL_SIGS);\
 574                        }                                                     \
 575                }                                                             \
 576                                                                               \
 577                set_current_state(TASK_RUNNING);                               \
 578                                                                               \
 579                if (condition)                                           \
 580                        break;                                           \
 581                if (cfs_signal_pending()) {                                 \
 582                        if (info->lwi_on_signal &&                   \
 583                            (__timeout == 0 || __allow_intr)) {         \
 584                                if (info->lwi_on_signal != LWI_ON_SIGNAL_NOOP) \
 585                                        info->lwi_on_signal(info->lwi_cb_data);\
 586                                ret = -EINTR;                             \
 587                                break;                                   \
 588                        }                                                     \
 589                        /* We have to do this here because some signals */     \
 590                        /* are not blockable - ie from strace(1).       */     \
 591                        /* In these cases we want to schedule_timeout() */     \
 592                        /* again, because we don't want that to return  */     \
 593                        /* -EINTR when the RPC actually succeeded.      */     \
 594                        /* the recalc_sigpending() below will deliver the */     \
 595                        /* signal properly.                          */     \
 596                        cfs_clear_sigpending();                         \
 597                }                                                             \
 598        }                                                                     \
 599                                                                               \
 600        cfs_restore_sigs(__blocked);                                       \
 601                                                                               \
 602        remove_wait_queue(&wq, &__wait);                                           \
 603} while (0)
 604
 605#define l_wait_event(wq, condition, info)                      \
 606({                                                            \
 607        int              __ret;                       \
 608        struct l_wait_info *__info = (info);                \
 609                                                                \
 610        __l_wait_event(wq, condition, __info,              \
 611                       __ret, add_wait_queue);             \
 612        __ret;                                            \
 613})
 614
 615#define l_wait_event_exclusive(wq, condition, info)          \
 616({                                                            \
 617        int              __ret;                       \
 618        struct l_wait_info *__info = (info);                \
 619                                                                \
 620        __l_wait_event(wq, condition, __info,              \
 621                       __ret, add_wait_queue_exclusive);         \
 622        __ret;                                            \
 623})
 624
 625#define l_wait_event_exclusive_head(wq, condition, info)        \
 626({                                                            \
 627        int              __ret;                       \
 628        struct l_wait_info *__info = (info);                \
 629                                                                \
 630        __l_wait_event(wq, condition, __info,              \
 631                       __ret, add_wait_queue_exclusive_head);    \
 632        __ret;                                            \
 633})
 634
 635#define l_wait_condition(wq, condition)                  \
 636({                                                            \
 637        struct l_wait_info lwi = { 0 };                  \
 638        l_wait_event(wq, condition, &lwi);                    \
 639})
 640
 641#define l_wait_condition_exclusive(wq, condition)              \
 642({                                                            \
 643        struct l_wait_info lwi = { 0 };                  \
 644        l_wait_event_exclusive(wq, condition, &lwi);        \
 645})
 646
 647#define l_wait_condition_exclusive_head(wq, condition)    \
 648({                                                            \
 649        struct l_wait_info lwi = { 0 };                  \
 650        l_wait_event_exclusive_head(wq, condition, &lwi);       \
 651})
 652
 653#define LIBLUSTRE_CLIENT (0)
 654
 655/** @} lib */
 656
 657#endif /* _LUSTRE_LIB_H */
 658