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