drivers/staging/lustre/lustre/include/lustre_log.h

   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.gnu.org/licenses/gpl-2.0.html
  19  *
  20  * GPL HEADER END
  21  */
  22 /*
  23  * Copyright (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved.
  24  * Use is subject to license terms.
  25  *
  26  * Copyright (c) 2012, 2015, Intel Corporation.
  27  */
  28 /*
  29  * This file is part of Lustre, http://www.lustre.org/
  30  * Lustre is a trademark of Sun Microsystems, Inc.
  31  *
  32  * lustre/include/lustre_log.h
  33  *
  34  * Generic infrastructure for managing a collection of logs.
  35  * These logs are used for:
  36  *
  37  * - orphan recovery: OST adds record on create
  38  * - mtime/size consistency: the OST adds a record on first write
  39  * - open/unlinked objects: OST adds a record on destroy
  40  *
  41  * - mds unlink log: the MDS adds an entry upon delete
  42  *
  43  * - raid1 replication log between OST's
  44  * - MDS replication logs
  45  */
  46
  47 #ifndef _LUSTRE_LOG_H
  48 #define _LUSTRE_LOG_H
  49
  50 /** \defgroup log log
  51  *
  52  * @{
  53  */
  54
  55 #include "obd_class.h"
  56 #include "lustre/lustre_idl.h"
  57
  58 #define LOG_NAME_LIMIT(logname, name)              \
  59         snprintf(logname, sizeof(logname), "LOGS/%s", name)
  60 #define LLOG_EEMPTY 4711
  61
  62 enum llog_open_param {
  63         LLOG_OPEN_EXISTS        = 0x0000,
  64         LLOG_OPEN_NEW           = 0x0001,
  65 };
  66
  67 struct plain_handle_data {
  68         struct list_head          phd_entry;
  69         struct llog_handle *phd_cat_handle;
  70         struct llog_cookie  phd_cookie; /* cookie of this log in its cat */
  71 };
  72
  73 struct cat_handle_data {
  74         struct list_head              chd_head;
  75         struct llog_handle     *chd_current_log; /* currently open log */
  76         struct llog_handle      *chd_next_log; /* llog to be used next */
  77 };
  78
  79 struct llog_handle;
  80
  81 /* llog.c  -  general API */
  82 int llog_init_handle(const struct lu_env *env, struct llog_handle *handle,
  83                      int flags, struct obd_uuid *uuid);
  84 int llog_process(const struct lu_env *env, struct llog_handle *loghandle,
  85                  llog_cb_t cb, void *data, void *catdata);
  86 int llog_process_or_fork(const struct lu_env *env,
  87                          struct llog_handle *loghandle,
  88                          llog_cb_t cb, void *data, void *catdata, bool fork);
  89 int llog_open(const struct lu_env *env, struct llog_ctxt *ctxt,
  90               struct llog_handle **lgh, struct llog_logid *logid,
  91               char *name, enum llog_open_param open_param);
  92 int llog_close(const struct lu_env *env, struct llog_handle *cathandle);
  93
  94 /* llog_process flags */
  95 #define LLOG_FLAG_NODEAMON 0x0001
  96
  97 /* llog_cat.c - catalog api */
  98 struct llog_process_data {
  99         /**
 100          * Any useful data needed while processing catalog. This is
 101          * passed later to process callback.
 102          */
 103         void            *lpd_data;
 104         /**
 105          * Catalog process callback function, called for each record
 106          * in catalog.
 107          */
 108         llog_cb_t           lpd_cb;
 109         /**
 110          * Start processing the catalog from startcat/startidx
 111          */
 112         int               lpd_startcat;
 113         int               lpd_startidx;
 114 };
 115
 116 struct llog_process_cat_data {
 117         /**
 118          * Temporary stored first_idx while scanning log.
 119          */
 120         int               lpcd_first_idx;
 121         /**
 122          * Temporary stored last_idx while scanning log.
 123          */
 124         int               lpcd_last_idx;
 125 };
 126
 127 struct thandle;
 128
 129 int llog_cat_close(const struct lu_env *env, struct llog_handle *cathandle);
 130 int llog_cat_process(const struct lu_env *env, struct llog_handle *cat_llh,
 131                      llog_cb_t cb, void *data, int startcat, int startidx);
 132
 133 /* llog_obd.c */
 134 int llog_setup(const struct lu_env *env, struct obd_device *obd,
 135                struct obd_llog_group *olg, int index,
 136                struct obd_device *disk_obd, struct llog_operations *op);
 137 int __llog_ctxt_put(const struct lu_env *env, struct llog_ctxt *ctxt);
 138 int llog_cleanup(const struct lu_env *env, struct llog_ctxt *);
 139
 140 /* llog_net.c */
 141 int llog_initiator_connect(struct llog_ctxt *ctxt);
 142
 143 struct llog_operations {
 144         int (*lop_next_block)(const struct lu_env *env, struct llog_handle *h,
 145                               int *curr_idx, int next_idx, __u64 *offset,
 146                               void *buf, int len);
 147         int (*lop_prev_block)(const struct lu_env *env, struct llog_handle *h,
 148                               int prev_idx, void *buf, int len);
 149         int (*lop_read_header)(const struct lu_env *env,
 150                                struct llog_handle *handle);
 151         int (*lop_setup)(const struct lu_env *env, struct obd_device *obd,
 152                          struct obd_llog_group *olg, int ctxt_idx,
 153                          struct obd_device *disk_obd);
 154         int (*lop_sync)(struct llog_ctxt *ctxt, struct obd_export *exp,
 155                         int flags);
 156         int (*lop_cleanup)(const struct lu_env *env, struct llog_ctxt *ctxt);
 157         int (*lop_cancel)(const struct lu_env *env, struct llog_ctxt *ctxt,
 158                           struct llog_cookie *cookies, int flags);
 159         int (*lop_connect)(struct llog_ctxt *ctxt, struct llog_logid *logid,
 160                            struct llog_gen *gen, struct obd_uuid *uuid);
 161         /**
 162          * Any llog file must be opened first using llog_open().  Llog can be
 163          * opened by name, logid or without both, in last case the new logid
 164          * will be generated.
 165          */
 166         int (*lop_open)(const struct lu_env *env, struct llog_handle *lgh,
 167                         struct llog_logid *logid, char *name,
 168                         enum llog_open_param);
 169         /**
 170          * Opened llog may not exist and this must be checked where needed using
 171          * the llog_exist() call.
 172          */
 173         int (*lop_exist)(struct llog_handle *lgh);
 174         /**
 175          * Close llog file and calls llog_free_handle() implicitly.
 176          * Any opened llog must be closed by llog_close() call.
 177          */
 178         int (*lop_close)(const struct lu_env *env, struct llog_handle *handle);
 179         /**
 180          * Create new llog file. The llog must be opened.
 181          * Must be used only for local llog operations.
 182          */
 183         int (*lop_declare_create)(const struct lu_env *env,
 184                                   struct llog_handle *handle,
 185                                   struct thandle *th);
 186         /**
 187          * write new record in llog. It appends records usually but can edit
 188          * existing records too.
 189          */
 190         int (*lop_declare_write_rec)(const struct lu_env *env,
 191                                      struct llog_handle *lgh,
 192                                      struct llog_rec_hdr *rec,
 193                                      int idx, struct thandle *th);
 194         int (*lop_write_rec)(const struct lu_env *env,
 195                              struct llog_handle *loghandle,
 196                              struct llog_rec_hdr *rec,
 197                              struct llog_cookie *cookie, int cookiecount,
 198                              void *buf, int idx, struct thandle *th);
 199         /**
 200          * Add new record in llog catalog. Does the same as llog_write_rec()
 201          * but using llog catalog.
 202          */
 203         int (*lop_declare_add)(const struct lu_env *env,
 204                                struct llog_handle *lgh,
 205                                struct llog_rec_hdr *rec, struct thandle *th);
 206         int (*lop_add)(const struct lu_env *env, struct llog_handle *lgh,
 207                        struct llog_rec_hdr *rec, struct llog_cookie *cookie,
 208                        void *buf, struct thandle *th);
 209 };
 210
 211 /* In-memory descriptor for a log object or log catalog */
 212 struct llog_handle {
 213         struct rw_semaphore      lgh_lock;
 214         spinlock_t               lgh_hdr_lock; /* protect lgh_hdr data */
 215         struct llog_logid        lgh_id; /* id of this log */
 216         struct llog_log_hdr     *lgh_hdr;
 217         int                      lgh_last_idx;
 218         int                      lgh_cur_idx; /* used during llog_process */
 219         __u64                    lgh_cur_offset; /* used during llog_process */
 220         struct llog_ctxt        *lgh_ctxt;
 221         union {
 222                 struct plain_handle_data         phd;
 223                 struct cat_handle_data           chd;
 224         } u;
 225         char                    *lgh_name;
 226         void                    *private_data;
 227         struct llog_operations  *lgh_logops;
 228         atomic_t                 lgh_refcount;
 229 };
 230
 231 #define LLOG_CTXT_FLAG_UNINITIALIZED     0x00000001
 232 #define LLOG_CTXT_FLAG_STOP              0x00000002
 233
 234 struct llog_ctxt {
 235         int                   loc_idx; /* my index the obd array of ctxt's */
 236         struct obd_device       *loc_obd; /* points back to the containing obd*/
 237         struct obd_llog_group   *loc_olg; /* group containing that ctxt */
 238         struct obd_export       *loc_exp; /* parent "disk" export (e.g. MDS) */
 239         struct obd_import       *loc_imp; /* to use in RPC's: can be backward
 240                                            * pointing import
 241                                            */
 242         struct llog_operations  *loc_logops;
 243         struct llog_handle      *loc_handle;
 244         struct mutex             loc_mutex; /* protect loc_imp */
 245         atomic_t             loc_refcount;
 246         long                 loc_flags; /* flags, see above defines */
 247 };
 248
 249 #define LLOG_PROC_BREAK 0x0001
 250 #define LLOG_DEL_RECORD 0x0002
 251
 252 static inline int llog_handle2ops(struct llog_handle *loghandle,
 253                                   struct llog_operations **lop)
 254 {
 255         if (!loghandle || !loghandle->lgh_logops)
 256                 return -EINVAL;
 257
 258         *lop = loghandle->lgh_logops;
 259         return 0;
 260 }
 261
 262 static inline struct llog_ctxt *llog_ctxt_get(struct llog_ctxt *ctxt)
 263 {
 264         atomic_inc(&ctxt->loc_refcount);
 265         CDEBUG(D_INFO, "GETting ctxt %p : new refcount %d\n", ctxt,
 266                atomic_read(&ctxt->loc_refcount));
 267         return ctxt;
 268 }
 269
 270 static inline void llog_ctxt_put(struct llog_ctxt *ctxt)
 271 {
 272         if (!ctxt)
 273                 return;
 274         LASSERT_ATOMIC_GT_LT(&ctxt->loc_refcount, 0, LI_POISON);
 275         CDEBUG(D_INFO, "PUTting ctxt %p : new refcount %d\n", ctxt,
 276                atomic_read(&ctxt->loc_refcount) - 1);
 277         __llog_ctxt_put(NULL, ctxt);
 278 }
 279
 280 static inline void llog_group_init(struct obd_llog_group *olg, int group)
 281 {
 282         init_waitqueue_head(&olg->olg_waitq);
 283         spin_lock_init(&olg->olg_lock);
 284         mutex_init(&olg->olg_cat_processing);
 285         olg->olg_seq = group;
 286 }
 287
 288 static inline int llog_group_set_ctxt(struct obd_llog_group *olg,
 289                                       struct llog_ctxt *ctxt, int index)
 290 {
 291         LASSERT(index >= 0 && index < LLOG_MAX_CTXTS);
 292
 293         spin_lock(&olg->olg_lock);
 294         if (olg->olg_ctxts[index]) {
 295                 spin_unlock(&olg->olg_lock);
 296                 return -EEXIST;
 297         }
 298         olg->olg_ctxts[index] = ctxt;
 299         spin_unlock(&olg->olg_lock);
 300         return 0;
 301 }
 302
 303 static inline struct llog_ctxt *llog_group_get_ctxt(struct obd_llog_group *olg,
 304                                                     int index)
 305 {
 306         struct llog_ctxt *ctxt;
 307
 308         LASSERT(index >= 0 && index < LLOG_MAX_CTXTS);
 309
 310         spin_lock(&olg->olg_lock);
 311         if (!olg->olg_ctxts[index])
 312                 ctxt = NULL;
 313         else
 314                 ctxt = llog_ctxt_get(olg->olg_ctxts[index]);
 315         spin_unlock(&olg->olg_lock);
 316         return ctxt;
 317 }
 318
 319 static inline void llog_group_clear_ctxt(struct obd_llog_group *olg, int index)
 320 {
 321         LASSERT(index >= 0 && index < LLOG_MAX_CTXTS);
 322         spin_lock(&olg->olg_lock);
 323         olg->olg_ctxts[index] = NULL;
 324         spin_unlock(&olg->olg_lock);
 325 }
 326
 327 static inline struct llog_ctxt *llog_get_context(struct obd_device *obd,
 328                                                  int index)
 329 {
 330         return llog_group_get_ctxt(&obd->obd_olg, index);
 331 }
 332
 333 static inline int llog_group_ctxt_null(struct obd_llog_group *olg, int index)
 334 {
 335         return (!olg->olg_ctxts[index]);
 336 }
 337
 338 static inline int llog_ctxt_null(struct obd_device *obd, int index)
 339 {
 340         return llog_group_ctxt_null(&obd->obd_olg, index);
 341 }
 342
 343 static inline int llog_next_block(const struct lu_env *env,
 344                                   struct llog_handle *loghandle, int *cur_idx,
 345                                   int next_idx, __u64 *cur_offset, void *buf,
 346                                   int len)
 347 {
 348         struct llog_operations *lop;
 349         int rc;
 350
 351         rc = llog_handle2ops(loghandle, &lop);
 352         if (rc)
 353                 return rc;
 354         if (!lop->lop_next_block)
 355                 return -EOPNOTSUPP;
 356
 357         rc = lop->lop_next_block(env, loghandle, cur_idx, next_idx,
 358                                  cur_offset, buf, len);
 359         return rc;
 360 }
 361
 362 /* llog.c */
 363 int llog_declare_write_rec(const struct lu_env *env,
 364                            struct llog_handle *handle,
 365                            struct llog_rec_hdr *rec, int idx,
 366                            struct thandle *th);
 367 int llog_write_rec(const struct lu_env *env, struct llog_handle *handle,
 368                    struct llog_rec_hdr *rec, struct llog_cookie *logcookies,
 369                    int numcookies, void *buf, int idx, struct thandle *th);
 370 int lustre_process_log(struct super_block *sb, char *logname,
 371                        struct config_llog_instance *cfg);
 372 int lustre_end_log(struct super_block *sb, char *logname,
 373                    struct config_llog_instance *cfg);
 374 /** @} log */
 375
 376 #endif