1 /* 2 * Copyright (c) 2000-2003,2005 Silicon Graphics, Inc. 3 * All Rights Reserved. 4 * 5 * This program is free software; you can redistribute it and/or 6 * modify it under the terms of the GNU General Public License as 7 * published by the Free Software Foundation. 8 * 9 * This program is distributed in the hope that it would be useful, 10 * but WITHOUT ANY WARRANTY; without even the implied warranty of 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12 * GNU General Public License for more details. 13 * 14 * You should have received a copy of the GNU General Public License 15 * along with this program; if not, write the Free Software Foundation, 16 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA 17 */ 18 #ifndef __XFS_LOG_PRIV_H__ 19 #define __XFS_LOG_PRIV_H__ 20 21 struct xfs_buf; 22 struct ktrace; 23 struct log; 24 struct xlog_ticket; 25 struct xfs_buf_cancel; 26 struct xfs_mount; 27 28 /* 29 * Macros, structures, prototypes for internal log manager use. 30 */ 31 32 #define XLOG_MIN_ICLOGS 2 33 #define XLOG_MAX_ICLOGS 8 34 #define XLOG_HEADER_MAGIC_NUM 0xFEEDbabe /* Invalid cycle number */ 35 #define XLOG_VERSION_1 1 36 #define XLOG_VERSION_2 2 /* Large IClogs, Log sunit */ 37 #define XLOG_VERSION_OKBITS (XLOG_VERSION_1 | XLOG_VERSION_2) 38 #define XLOG_MIN_RECORD_BSIZE (16*1024) /* eventually 32k */ 39 #define XLOG_BIG_RECORD_BSIZE (32*1024) /* 32k buffers */ 40 #define XLOG_MAX_RECORD_BSIZE (256*1024) 41 #define XLOG_HEADER_CYCLE_SIZE (32*1024) /* cycle data in header */ 42 #define XLOG_MIN_RECORD_BSHIFT 14 /* 16384 == 1 << 14 */ 43 #define XLOG_BIG_RECORD_BSHIFT 15 /* 32k == 1 << 15 */ 44 #define XLOG_MAX_RECORD_BSHIFT 18 /* 256k == 1 << 18 */ 45 #define XLOG_BTOLSUNIT(log, b) (((b)+(log)->l_mp->m_sb.sb_logsunit-1) / \ 46 (log)->l_mp->m_sb.sb_logsunit) 47 #define XLOG_LSUNITTOB(log, su) ((su) * (log)->l_mp->m_sb.sb_logsunit) 48 49 #define XLOG_HEADER_SIZE 512 50 51 #define XLOG_REC_SHIFT(log) \ 52 BTOBB(1 << (xfs_sb_version_haslogv2(&log->l_mp->m_sb) ? \ 53 XLOG_MAX_RECORD_BSHIFT : XLOG_BIG_RECORD_BSHIFT)) 54 #define XLOG_TOTAL_REC_SHIFT(log) \ 55 BTOBB(XLOG_MAX_ICLOGS << (xfs_sb_version_haslogv2(&log->l_mp->m_sb) ? \ 56 XLOG_MAX_RECORD_BSHIFT : XLOG_BIG_RECORD_BSHIFT)) 57 58 59 static inline xfs_lsn_t xlog_assign_lsn(uint cycle, uint block) 60 { 61 return ((xfs_lsn_t)cycle << 32) | block; 62 } 63 64 static inline uint xlog_get_cycle(char *ptr) 65 { 66 if (be32_to_cpu(*(__be32 *)ptr) == XLOG_HEADER_MAGIC_NUM) 67 return be32_to_cpu(*((__be32 *)ptr + 1)); 68 else 69 return be32_to_cpu(*(__be32 *)ptr); 70 } 71 72 #define BLK_AVG(blk1, blk2) ((blk1+blk2) >> 1) 73 74 #ifdef __KERNEL__ 75 76 /* 77 * get client id from packed copy. 78 * 79 * this hack is here because the xlog_pack code copies four bytes 80 * of xlog_op_header containing the fields oh_clientid, oh_flags 81 * and oh_res2 into the packed copy. 82 * 83 * later on this four byte chunk is treated as an int and the 84 * client id is pulled out. 85 * 86 * this has endian issues, of course. 87 */ 88 static inline uint xlog_get_client_id(__be32 i) 89 { 90 return be32_to_cpu(i) >> 24; 91 } 92 93 #define xlog_panic(args...) cmn_err(CE_PANIC, ## args) 94 #define xlog_exit(args...) cmn_err(CE_PANIC, ## args) 95 #define xlog_warn(args...) cmn_err(CE_WARN, ## args) 96 97 /* 98 * In core log state 99 */ 100 #define XLOG_STATE_ACTIVE 0x0001 /* Current IC log being written to */ 101 #define XLOG_STATE_WANT_SYNC 0x0002 /* Want to sync this iclog; no more writes */ 102 #define XLOG_STATE_SYNCING 0x0004 /* This IC log is syncing */ 103 #define XLOG_STATE_DONE_SYNC 0x0008 /* Done syncing to disk */ 104 #define XLOG_STATE_DO_CALLBACK \ 105 0x0010 /* Process callback functions */ 106 #define XLOG_STATE_CALLBACK 0x0020 /* Callback functions now */ 107 #define XLOG_STATE_DIRTY 0x0040 /* Dirty IC log, not ready for ACTIVE status*/ 108 #define XLOG_STATE_IOERROR 0x0080 /* IO error happened in sync'ing log */ 109 #define XLOG_STATE_ALL 0x7FFF /* All possible valid flags */ 110 #define XLOG_STATE_NOTUSED 0x8000 /* This IC log not being used */ 111 #endif /* __KERNEL__ */ 112 113 /* 114 * Flags to log operation header 115 * 116 * The first write of a new transaction will be preceded with a start 117 * record, XLOG_START_TRANS. Once a transaction is committed, a commit 118 * record is written, XLOG_COMMIT_TRANS. If a single region can not fit into 119 * the remainder of the current active in-core log, it is split up into 120 * multiple regions. Each partial region will be marked with a 121 * XLOG_CONTINUE_TRANS until the last one, which gets marked with XLOG_END_TRANS. 122 * 123 */ 124 #define XLOG_START_TRANS 0x01 /* Start a new transaction */ 125 #define XLOG_COMMIT_TRANS 0x02 /* Commit this transaction */ 126 #define XLOG_CONTINUE_TRANS 0x04 /* Cont this trans into new region */ 127 #define XLOG_WAS_CONT_TRANS 0x08 /* Cont this trans into new region */ 128 #define XLOG_END_TRANS 0x10 /* End a continued transaction */ 129 #define XLOG_UNMOUNT_TRANS 0x20 /* Unmount a filesystem transaction */ 130 131 #ifdef __KERNEL__ 132 /* 133 * Flags to log ticket 134 */ 135 #define XLOG_TIC_INITED 0x1 /* has been initialized */ 136 #define XLOG_TIC_PERM_RESERV 0x2 /* permanent reservation */ 137 #define XLOG_TIC_IN_Q 0x4 138 #endif /* __KERNEL__ */ 139 140 #define XLOG_UNMOUNT_TYPE 0x556e /* Un for Unmount */ 141 142 /* 143 * Flags for log structure 144 */ 145 #define XLOG_CHKSUM_MISMATCH 0x1 /* used only during recovery */ 146 #define XLOG_ACTIVE_RECOVERY 0x2 /* in the middle of recovery */ 147 #define XLOG_RECOVERY_NEEDED 0x4 /* log was recovered */ 148 #define XLOG_IO_ERROR 0x8 /* log hit an I/O error, and being 149 shutdown */ 150 typedef __uint32_t xlog_tid_t; 151 152 153 #ifdef __KERNEL__ 154 /* 155 * Below are states for covering allocation transactions. 156 * By covering, we mean changing the h_tail_lsn in the last on-disk 157 * log write such that no allocation transactions will be re-done during 158 * recovery after a system crash. Recovery starts at the last on-disk 159 * log write. 160 * 161 * These states are used to insert dummy log entries to cover 162 * space allocation transactions which can undo non-transactional changes 163 * after a crash. Writes to a file with space 164 * already allocated do not result in any transactions. Allocations 165 * might include space beyond the EOF. So if we just push the EOF a 166 * little, the last transaction for the file could contain the wrong 167 * size. If there is no file system activity, after an allocation 168 * transaction, and the system crashes, the allocation transaction 169 * will get replayed and the file will be truncated. This could 170 * be hours/days/... after the allocation occurred. 171 * 172 * The fix for this is to do two dummy transactions when the 173 * system is idle. We need two dummy transaction because the h_tail_lsn 174 * in the log record header needs to point beyond the last possible 175 * non-dummy transaction. The first dummy changes the h_tail_lsn to 176 * the first transaction before the dummy. The second dummy causes 177 * h_tail_lsn to point to the first dummy. Recovery starts at h_tail_lsn. 178 * 179 * These dummy transactions get committed when everything 180 * is idle (after there has been some activity). 181 * 182 * There are 5 states used to control this. 183 * 184 * IDLE -- no logging has been done on the file system or 185 * we are done covering previous transactions. 186 * NEED -- logging has occurred and we need a dummy transaction 187 * when the log becomes idle. 188 * DONE -- we were in the NEED state and have committed a dummy 189 * transaction. 190 * NEED2 -- we detected that a dummy transaction has gone to the 191 * on disk log with no other transactions. 192 * DONE2 -- we committed a dummy transaction when in the NEED2 state. 193 * 194 * There are two places where we switch states: 195 * 196 * 1.) In xfs_sync, when we detect an idle log and are in NEED or NEED2. 197 * We commit the dummy transaction and switch to DONE or DONE2, 198 * respectively. In all other states, we don't do anything. 199 * 200 * 2.) When we finish writing the on-disk log (xlog_state_clean_log). 201 * 202 * No matter what state we are in, if this isn't the dummy 203 * transaction going out, the next state is NEED. 204 * So, if we aren't in the DONE or DONE2 states, the next state 205 * is NEED. We can't be finishing a write of the dummy record 206 * unless it was committed and the state switched to DONE or DONE2. 207 * 208 * If we are in the DONE state and this was a write of the 209 * dummy transaction, we move to NEED2. 210 * 211 * If we are in the DONE2 state and this was a write of the 212 * dummy transaction, we move to IDLE. 213 * 214 * 215 * Writing only one dummy transaction can get appended to 216 * one file space allocation. When this happens, the log recovery 217 * code replays the space allocation and a file could be truncated. 218 * This is why we have the NEED2 and DONE2 states before going idle. 219 */ 220 221 #define XLOG_STATE_COVER_IDLE 0 222 #define XLOG_STATE_COVER_NEED 1 223 #define XLOG_STATE_COVER_DONE 2 224 #define XLOG_STATE_COVER_NEED2 3 225 #define XLOG_STATE_COVER_DONE2 4 226 227 #define XLOG_COVER_OPS 5 228 229 230 /* Ticket reservation region accounting */ 231 #define XLOG_TIC_LEN_MAX 15 232 233 /* 234 * Reservation region 235 * As would be stored in xfs_log_iovec but without the i_addr which 236 * we don't care about. 237 */ 238 typedef struct xlog_res { 239 uint r_len; /* region length :4 */ 240 uint r_type; /* region's transaction type :4 */ 241 } xlog_res_t; 242 243 typedef struct xlog_ticket { 244 sv_t t_wait; /* ticket wait queue : 20 */ 245 struct xlog_ticket *t_next; /* :4|8 */ 246 struct xlog_ticket *t_prev; /* :4|8 */ 247 xlog_tid_t t_tid; /* transaction identifier : 4 */ 248 atomic_t t_ref; /* ticket reference count : 4 */ 249 int t_curr_res; /* current reservation in bytes : 4 */ 250 int t_unit_res; /* unit reservation in bytes : 4 */ 251 char t_ocnt; /* original count : 1 */ 252 char t_cnt; /* current count : 1 */ 253 char t_clientid; /* who does this belong to; : 1 */ 254 char t_flags; /* properties of reservation : 1 */ 255 uint t_trans_type; /* transaction type : 4 */ 256 257 /* reservation array fields */ 258 uint t_res_num; /* num in array : 4 */ 259 uint t_res_num_ophdrs; /* num op hdrs : 4 */ 260 uint t_res_arr_sum; /* array sum : 4 */ 261 uint t_res_o_flow; /* sum overflow : 4 */ 262 xlog_res_t t_res_arr[XLOG_TIC_LEN_MAX]; /* array of res : 8 * 15 */ 263 } xlog_ticket_t; 264 265 #endif 266 267 268 typedef struct xlog_op_header { 269 __be32 oh_tid; /* transaction id of operation : 4 b */ 270 __be32 oh_len; /* bytes in data region : 4 b */ 271 __u8 oh_clientid; /* who sent me this : 1 b */ 272 __u8 oh_flags; /* : 1 b */ 273 __u16 oh_res2; /* 32 bit align : 2 b */ 274 } xlog_op_header_t; 275 276 277 /* valid values for h_fmt */ 278 #define XLOG_FMT_UNKNOWN 0 279 #define XLOG_FMT_LINUX_LE 1 280 #define XLOG_FMT_LINUX_BE 2 281 #define XLOG_FMT_IRIX_BE 3 282 283 /* our fmt */ 284 #ifdef XFS_NATIVE_HOST 285 #define XLOG_FMT XLOG_FMT_LINUX_BE 286 #else 287 #define XLOG_FMT XLOG_FMT_LINUX_LE 288 #endif 289 290 typedef struct xlog_rec_header { 291 __be32 h_magicno; /* log record (LR) identifier : 4 */ 292 __be32 h_cycle; /* write cycle of log : 4 */ 293 __be32 h_version; /* LR version : 4 */ 294 __be32 h_len; /* len in bytes; should be 64-bit aligned: 4 */ 295 __be64 h_lsn; /* lsn of this LR : 8 */ 296 __be64 h_tail_lsn; /* lsn of 1st LR w/ buffers not committed: 8 */ 297 __be32 h_chksum; /* may not be used; non-zero if used : 4 */ 298 __be32 h_prev_block; /* block number to previous LR : 4 */ 299 __be32 h_num_logops; /* number of log operations in this LR : 4 */ 300 __be32 h_cycle_data[XLOG_HEADER_CYCLE_SIZE / BBSIZE]; 301 /* new fields */ 302 __be32 h_fmt; /* format of log record : 4 */ 303 uuid_t h_fs_uuid; /* uuid of FS : 16 */ 304 __be32 h_size; /* iclog size : 4 */ 305 } xlog_rec_header_t; 306 307 typedef struct xlog_rec_ext_header { 308 __be32 xh_cycle; /* write cycle of log : 4 */ 309 __be32 xh_cycle_data[XLOG_HEADER_CYCLE_SIZE / BBSIZE]; /* : 256 */ 310 } xlog_rec_ext_header_t; 311 312 #ifdef __KERNEL__ 313 314 /* 315 * Quite misnamed, because this union lays out the actual on-disk log buffer. 316 */ 317 typedef union xlog_in_core2 { 318 xlog_rec_header_t hic_header; 319 xlog_rec_ext_header_t hic_xheader; 320 char hic_sector[XLOG_HEADER_SIZE]; 321 } xlog_in_core_2_t; 322 323 /* 324 * - A log record header is 512 bytes. There is plenty of room to grow the 325 * xlog_rec_header_t into the reserved space. 326 * - ic_data follows, so a write to disk can start at the beginning of 327 * the iclog. 328 * - ic_forcewait is used to implement synchronous forcing of the iclog to disk. 329 * - ic_next is the pointer to the next iclog in the ring. 330 * - ic_bp is a pointer to the buffer used to write this incore log to disk. 331 * - ic_log is a pointer back to the global log structure. 332 * - ic_callback is a linked list of callback function/argument pairs to be 333 * called after an iclog finishes writing. 334 * - ic_size is the full size of the header plus data. 335 * - ic_offset is the current number of bytes written to in this iclog. 336 * - ic_refcnt is bumped when someone is writing to the log. 337 * - ic_state is the state of the iclog. 338 * 339 * Because of cacheline contention on large machines, we need to separate 340 * various resources onto different cachelines. To start with, make the 341 * structure cacheline aligned. The following fields can be contended on 342 * by independent processes: 343 * 344 * - ic_callback_* 345 * - ic_refcnt 346 * - fields protected by the global l_icloglock 347 * 348 * so we need to ensure that these fields are located in separate cachelines. 349 * We'll put all the read-only and l_icloglock fields in the first cacheline, 350 * and move everything else out to subsequent cachelines. 351 */ 352 typedef struct xlog_in_core { 353 sv_t ic_force_wait; 354 sv_t ic_write_wait; 355 struct xlog_in_core *ic_next; 356 struct xlog_in_core *ic_prev; 357 struct xfs_buf *ic_bp; 358 struct log *ic_log; 359 int ic_size; 360 int ic_offset; 361 int ic_bwritecnt; 362 ushort_t ic_state; 363 char *ic_datap; /* pointer to iclog data */ 364 #ifdef XFS_LOG_TRACE 365 struct ktrace *ic_trace; 366 #endif 367 368 /* Callback structures need their own cacheline */ 369 spinlock_t ic_callback_lock ____cacheline_aligned_in_smp; 370 xfs_log_callback_t *ic_callback; 371 xfs_log_callback_t **ic_callback_tail; 372 373 /* reference counts need their own cacheline */ 374 atomic_t ic_refcnt ____cacheline_aligned_in_smp; 375 xlog_in_core_2_t *ic_data; 376 #define ic_header ic_data->hic_header 377 } xlog_in_core_t; 378 379 /* 380 * The reservation head lsn is not made up of a cycle number and block number. 381 * Instead, it uses a cycle number and byte number. Logs don't expect to 382 * overflow 31 bits worth of byte offset, so using a byte number will mean 383 * that round off problems won't occur when releasing partial reservations. 384 */ 385 typedef struct log { 386 /* The following fields don't need locking */ 387 struct xfs_mount *l_mp; /* mount point */ 388 struct xfs_ail *l_ailp; /* AIL log is working with */ 389 struct xfs_buf *l_xbuf; /* extra buffer for log 390 * wrapping */ 391 struct xfs_buftarg *l_targ; /* buftarg of log */ 392 uint l_flags; 393 uint l_quotaoffs_flag; /* XFS_DQ_*, for QUOTAOFFs */ 394 struct xfs_buf_cancel **l_buf_cancel_table; 395 int l_iclog_hsize; /* size of iclog header */ 396 int l_iclog_heads; /* # of iclog header sectors */ 397 uint l_sectbb_log; /* log2 of sector size in BBs */ 398 uint l_sectbb_mask; /* sector size (in BBs) 399 * alignment mask */ 400 int l_iclog_size; /* size of log in bytes */ 401 int l_iclog_size_log; /* log power size of log */ 402 int l_iclog_bufs; /* number of iclog buffers */ 403 xfs_daddr_t l_logBBstart; /* start block of log */ 404 int l_logsize; /* size of log in bytes */ 405 int l_logBBsize; /* size of log in BB chunks */ 406 407 /* The following block of fields are changed while holding icloglock */ 408 sv_t l_flush_wait ____cacheline_aligned_in_smp; 409 /* waiting for iclog flush */ 410 int l_covered_state;/* state of "covering disk 411 * log entries" */ 412 xlog_in_core_t *l_iclog; /* head log queue */ 413 spinlock_t l_icloglock; /* grab to change iclog state */ 414 xfs_lsn_t l_tail_lsn; /* lsn of 1st LR with unflushed 415 * buffers */ 416 xfs_lsn_t l_last_sync_lsn;/* lsn of last LR on disk */ 417 int l_curr_cycle; /* Cycle number of log writes */ 418 int l_prev_cycle; /* Cycle number before last 419 * block increment */ 420 int l_curr_block; /* current logical log block */ 421 int l_prev_block; /* previous logical log block */ 422 423 /* The following block of fields are changed while holding grant_lock */ 424 spinlock_t l_grant_lock ____cacheline_aligned_in_smp; 425 xlog_ticket_t *l_reserve_headq; 426 xlog_ticket_t *l_write_headq; 427 int l_grant_reserve_cycle; 428 int l_grant_reserve_bytes; 429 int l_grant_write_cycle; 430 int l_grant_write_bytes; 431 432 #ifdef XFS_LOG_TRACE 433 struct ktrace *l_grant_trace; 434 #endif 435 436 /* The following field are used for debugging; need to hold icloglock */ 437 #ifdef DEBUG 438 char *l_iclog_bak[XLOG_MAX_ICLOGS]; 439 #endif 440 441 } xlog_t; 442 443 #define XLOG_FORCED_SHUTDOWN(log) ((log)->l_flags & XLOG_IO_ERROR) 444 445 446 /* common routines */ 447 extern xfs_lsn_t xlog_assign_tail_lsn(struct xfs_mount *mp); 448 extern int xlog_find_tail(xlog_t *log, 449 xfs_daddr_t *head_blk, 450 xfs_daddr_t *tail_blk); 451 extern int xlog_recover(xlog_t *log); 452 extern int xlog_recover_finish(xlog_t *log); 453 extern void xlog_pack_data(xlog_t *log, xlog_in_core_t *iclog, int); 454 extern void xlog_recover_process_iunlinks(xlog_t *log); 455 456 extern struct xfs_buf *xlog_get_bp(xlog_t *, int); 457 extern void xlog_put_bp(struct xfs_buf *); 458 extern int xlog_bread(xlog_t *, xfs_daddr_t, int, struct xfs_buf *); 459 460 extern kmem_zone_t *xfs_log_ticket_zone; 461 462 /* iclog tracing */ 463 #define XLOG_TRACE_GRAB_FLUSH 1 464 #define XLOG_TRACE_REL_FLUSH 2 465 #define XLOG_TRACE_SLEEP_FLUSH 3 466 #define XLOG_TRACE_WAKE_FLUSH 4 467 468 /* 469 * Unmount record type is used as a pseudo transaction type for the ticket. 470 * It's value must be outside the range of XFS_TRANS_* values. 471 */ 472 #define XLOG_UNMOUNT_REC_TYPE (-1U) 473 474 #endif /* __KERNEL__ */ 475 476 #endif /* __XFS_LOG_PRIV_H__ */ 477