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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
Nathan Scott7b718762005-11-02 14:58:39 +11002 * Copyright (c) 2000-2005 Silicon Graphics, Inc.
3 * All Rights Reserved.
Linus Torvalds1da177e2005-04-16 15:20:36 -07004 *
Nathan Scott7b718762005-11-02 14:58:39 +11005 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License as
Linus Torvalds1da177e2005-04-16 15:20:36 -07007 * published by the Free Software Foundation.
8 *
Nathan Scott7b718762005-11-02 14:58:39 +11009 * 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.
Linus Torvalds1da177e2005-04-16 15:20:36 -070013 *
Nathan Scott7b718762005-11-02 14:58:39 +110014 * 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
Linus Torvalds1da177e2005-04-16 15:20:36 -070017 */
Linus Torvalds1da177e2005-04-16 15:20:36 -070018#include "xfs.h"
Nathan Scotta844f452005-11-02 14:38:42 +110019#include "xfs_fs.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070020#include "xfs_types.h"
Nathan Scotta844f452005-11-02 14:38:42 +110021#include "xfs_bit.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070022#include "xfs_log.h"
Nathan Scotta844f452005-11-02 14:38:42 +110023#include "xfs_inum.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070024#include "xfs_trans.h"
Nathan Scotta844f452005-11-02 14:38:42 +110025#include "xfs_sb.h"
26#include "xfs_ag.h"
Nathan Scotta844f452005-11-02 14:38:42 +110027#include "xfs_dir2.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070028#include "xfs_dmapi.h"
29#include "xfs_mount.h"
30#include "xfs_error.h"
31#include "xfs_log_priv.h"
32#include "xfs_buf_item.h"
Nathan Scotta844f452005-11-02 14:38:42 +110033#include "xfs_bmap_btree.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070034#include "xfs_alloc_btree.h"
Nathan Scotta844f452005-11-02 14:38:42 +110035#include "xfs_ialloc_btree.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070036#include "xfs_log_recover.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070037#include "xfs_trans_priv.h"
Nathan Scotta844f452005-11-02 14:38:42 +110038#include "xfs_dir2_sf.h"
39#include "xfs_attr_sf.h"
40#include "xfs_dinode.h"
41#include "xfs_inode.h"
42#include "xfs_rw.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070043
44
45#define xlog_write_adv_cnt(ptr, len, off, bytes) \
46 { (ptr) += (bytes); \
47 (len) -= (bytes); \
48 (off) += (bytes);}
49
50/* Local miscellaneous function prototypes */
51STATIC int xlog_bdstrat_cb(struct xfs_buf *);
52STATIC int xlog_commit_record(xfs_mount_t *mp, xlog_ticket_t *ticket,
53 xlog_in_core_t **, xfs_lsn_t *);
54STATIC xlog_t * xlog_alloc_log(xfs_mount_t *mp,
55 xfs_buftarg_t *log_target,
56 xfs_daddr_t blk_offset,
57 int num_bblks);
58STATIC int xlog_space_left(xlog_t *log, int cycle, int bytes);
59STATIC int xlog_sync(xlog_t *log, xlog_in_core_t *iclog);
Nathan Scottc41564b2006-03-29 08:55:14 +100060STATIC void xlog_dealloc_log(xlog_t *log);
Linus Torvalds1da177e2005-04-16 15:20:36 -070061STATIC int xlog_write(xfs_mount_t *mp, xfs_log_iovec_t region[],
62 int nentries, xfs_log_ticket_t tic,
63 xfs_lsn_t *start_lsn,
64 xlog_in_core_t **commit_iclog,
65 uint flags);
66
67/* local state machine functions */
68STATIC void xlog_state_done_syncing(xlog_in_core_t *iclog, int);
69STATIC void xlog_state_do_callback(xlog_t *log,int aborted, xlog_in_core_t *iclog);
70STATIC int xlog_state_get_iclog_space(xlog_t *log,
71 int len,
72 xlog_in_core_t **iclog,
73 xlog_ticket_t *ticket,
74 int *continued_write,
75 int *logoffsetp);
76STATIC void xlog_state_put_ticket(xlog_t *log,
77 xlog_ticket_t *tic);
78STATIC int xlog_state_release_iclog(xlog_t *log,
79 xlog_in_core_t *iclog);
80STATIC void xlog_state_switch_iclogs(xlog_t *log,
81 xlog_in_core_t *iclog,
82 int eventual_size);
Christoph Hellwigf538d4d2005-11-02 10:26:59 +110083STATIC int xlog_state_sync(xlog_t *log,
84 xfs_lsn_t lsn,
85 uint flags,
86 int *log_flushed);
87STATIC int xlog_state_sync_all(xlog_t *log, uint flags, int *log_flushed);
Linus Torvalds1da177e2005-04-16 15:20:36 -070088STATIC void xlog_state_want_sync(xlog_t *log, xlog_in_core_t *iclog);
89
90/* local functions to manipulate grant head */
91STATIC int xlog_grant_log_space(xlog_t *log,
92 xlog_ticket_t *xtic);
93STATIC void xlog_grant_push_ail(xfs_mount_t *mp,
94 int need_bytes);
95STATIC void xlog_regrant_reserve_log_space(xlog_t *log,
96 xlog_ticket_t *ticket);
97STATIC int xlog_regrant_write_log_space(xlog_t *log,
98 xlog_ticket_t *ticket);
99STATIC void xlog_ungrant_log_space(xlog_t *log,
100 xlog_ticket_t *ticket);
101
102
103/* local ticket functions */
104STATIC void xlog_state_ticket_alloc(xlog_t *log);
105STATIC xlog_ticket_t *xlog_ticket_get(xlog_t *log,
106 int unit_bytes,
107 int count,
108 char clientid,
109 uint flags);
110STATIC void xlog_ticket_put(xlog_t *log, xlog_ticket_t *ticket);
111
Nathan Scottcfcbbbd2005-11-02 15:12:04 +1100112#if defined(DEBUG)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700113STATIC void xlog_verify_dest_ptr(xlog_t *log, __psint_t ptr);
114STATIC void xlog_verify_grant_head(xlog_t *log, int equals);
115STATIC void xlog_verify_iclog(xlog_t *log, xlog_in_core_t *iclog,
116 int count, boolean_t syncing);
117STATIC void xlog_verify_tail_lsn(xlog_t *log, xlog_in_core_t *iclog,
118 xfs_lsn_t tail_lsn);
119#else
120#define xlog_verify_dest_ptr(a,b)
121#define xlog_verify_grant_head(a,b)
122#define xlog_verify_iclog(a,b,c,d)
123#define xlog_verify_tail_lsn(a,b,c)
124#endif
125
Christoph Hellwigba0f32d2005-06-21 15:36:52 +1000126STATIC int xlog_iclogs_empty(xlog_t *log);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700127
Linus Torvalds1da177e2005-04-16 15:20:36 -0700128#if defined(XFS_LOG_TRACE)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700129void
130xlog_trace_loggrant(xlog_t *log, xlog_ticket_t *tic, xfs_caddr_t string)
131{
Tim Shimmin7e9c6392005-09-02 16:42:05 +1000132 unsigned long cnts;
133
134 if (!log->l_grant_trace) {
135 log->l_grant_trace = ktrace_alloc(2048, KM_NOSLEEP);
136 if (!log->l_grant_trace)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700137 return;
138 }
Tim Shimmin7e9c6392005-09-02 16:42:05 +1000139 /* ticket counts are 1 byte each */
140 cnts = ((unsigned long)tic->t_ocnt) | ((unsigned long)tic->t_cnt) << 8;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700141
142 ktrace_enter(log->l_grant_trace,
143 (void *)tic,
144 (void *)log->l_reserve_headq,
145 (void *)log->l_write_headq,
146 (void *)((unsigned long)log->l_grant_reserve_cycle),
147 (void *)((unsigned long)log->l_grant_reserve_bytes),
148 (void *)((unsigned long)log->l_grant_write_cycle),
149 (void *)((unsigned long)log->l_grant_write_bytes),
150 (void *)((unsigned long)log->l_curr_cycle),
151 (void *)((unsigned long)log->l_curr_block),
152 (void *)((unsigned long)CYCLE_LSN(log->l_tail_lsn)),
153 (void *)((unsigned long)BLOCK_LSN(log->l_tail_lsn)),
154 (void *)string,
Tim Shimmin7e9c6392005-09-02 16:42:05 +1000155 (void *)((unsigned long)tic->t_trans_type),
156 (void *)cnts,
157 (void *)((unsigned long)tic->t_curr_res),
158 (void *)((unsigned long)tic->t_unit_res));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700159}
160
161void
162xlog_trace_iclog(xlog_in_core_t *iclog, uint state)
163{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700164 if (!iclog->ic_trace)
165 iclog->ic_trace = ktrace_alloc(256, KM_SLEEP);
166 ktrace_enter(iclog->ic_trace,
167 (void *)((unsigned long)state),
Nathan Scottcfcbbbd2005-11-02 15:12:04 +1100168 (void *)((unsigned long)current_pid()),
169 (void *)NULL, (void *)NULL, (void *)NULL, (void *)NULL,
170 (void *)NULL, (void *)NULL, (void *)NULL, (void *)NULL,
171 (void *)NULL, (void *)NULL, (void *)NULL, (void *)NULL,
172 (void *)NULL, (void *)NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700173}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700174#else
175#define xlog_trace_loggrant(log,tic,string)
176#define xlog_trace_iclog(iclog,state)
177#endif /* XFS_LOG_TRACE */
178
Christoph Hellwigdd954c62006-01-11 15:34:50 +1100179
180static void
181xlog_ins_ticketq(struct xlog_ticket **qp, struct xlog_ticket *tic)
182{
183 if (*qp) {
184 tic->t_next = (*qp);
185 tic->t_prev = (*qp)->t_prev;
186 (*qp)->t_prev->t_next = tic;
187 (*qp)->t_prev = tic;
188 } else {
189 tic->t_prev = tic->t_next = tic;
190 *qp = tic;
191 }
192
193 tic->t_flags |= XLOG_TIC_IN_Q;
194}
195
196static void
197xlog_del_ticketq(struct xlog_ticket **qp, struct xlog_ticket *tic)
198{
199 if (tic == tic->t_next) {
200 *qp = NULL;
201 } else {
202 *qp = tic->t_next;
203 tic->t_next->t_prev = tic->t_prev;
204 tic->t_prev->t_next = tic->t_next;
205 }
206
207 tic->t_next = tic->t_prev = NULL;
208 tic->t_flags &= ~XLOG_TIC_IN_Q;
209}
210
211static void
212xlog_grant_sub_space(struct log *log, int bytes)
213{
214 log->l_grant_write_bytes -= bytes;
215 if (log->l_grant_write_bytes < 0) {
216 log->l_grant_write_bytes += log->l_logsize;
217 log->l_grant_write_cycle--;
218 }
219
220 log->l_grant_reserve_bytes -= bytes;
221 if ((log)->l_grant_reserve_bytes < 0) {
222 log->l_grant_reserve_bytes += log->l_logsize;
223 log->l_grant_reserve_cycle--;
224 }
225
226}
227
228static void
229xlog_grant_add_space_write(struct log *log, int bytes)
230{
231 log->l_grant_write_bytes += bytes;
232 if (log->l_grant_write_bytes > log->l_logsize) {
233 log->l_grant_write_bytes -= log->l_logsize;
234 log->l_grant_write_cycle++;
235 }
236}
237
238static void
239xlog_grant_add_space_reserve(struct log *log, int bytes)
240{
241 log->l_grant_reserve_bytes += bytes;
242 if (log->l_grant_reserve_bytes > log->l_logsize) {
243 log->l_grant_reserve_bytes -= log->l_logsize;
244 log->l_grant_reserve_cycle++;
245 }
246}
247
248static inline void
249xlog_grant_add_space(struct log *log, int bytes)
250{
251 xlog_grant_add_space_write(log, bytes);
252 xlog_grant_add_space_reserve(log, bytes);
253}
254
Christoph Hellwig0adba532007-08-30 17:21:46 +1000255static void
256xlog_tic_reset_res(xlog_ticket_t *tic)
257{
258 tic->t_res_num = 0;
259 tic->t_res_arr_sum = 0;
260 tic->t_res_num_ophdrs = 0;
261}
262
263static void
264xlog_tic_add_region(xlog_ticket_t *tic, uint len, uint type)
265{
266 if (tic->t_res_num == XLOG_TIC_LEN_MAX) {
267 /* add to overflow and start again */
268 tic->t_res_o_flow += tic->t_res_arr_sum;
269 tic->t_res_num = 0;
270 tic->t_res_arr_sum = 0;
271 }
272
273 tic->t_res_arr[tic->t_res_num].r_len = len;
274 tic->t_res_arr[tic->t_res_num].r_type = type;
275 tic->t_res_arr_sum += len;
276 tic->t_res_num++;
277}
Christoph Hellwigdd954c62006-01-11 15:34:50 +1100278
Linus Torvalds1da177e2005-04-16 15:20:36 -0700279/*
280 * NOTES:
281 *
282 * 1. currblock field gets updated at startup and after in-core logs
283 * marked as with WANT_SYNC.
284 */
285
286/*
287 * This routine is called when a user of a log manager ticket is done with
288 * the reservation. If the ticket was ever used, then a commit record for
289 * the associated transaction is written out as a log operation header with
290 * no data. The flag XLOG_TIC_INITED is set when the first write occurs with
291 * a given ticket. If the ticket was one with a permanent reservation, then
292 * a few operations are done differently. Permanent reservation tickets by
293 * default don't release the reservation. They just commit the current
294 * transaction with the belief that the reservation is still needed. A flag
295 * must be passed in before permanent reservations are actually released.
296 * When these type of tickets are not released, they need to be set into
297 * the inited state again. By doing this, a start record will be written
298 * out when the next write occurs.
299 */
300xfs_lsn_t
301xfs_log_done(xfs_mount_t *mp,
302 xfs_log_ticket_t xtic,
303 void **iclog,
304 uint flags)
305{
306 xlog_t *log = mp->m_log;
307 xlog_ticket_t *ticket = (xfs_log_ticket_t) xtic;
308 xfs_lsn_t lsn = 0;
309
Linus Torvalds1da177e2005-04-16 15:20:36 -0700310 if (XLOG_FORCED_SHUTDOWN(log) ||
311 /*
312 * If nothing was ever written, don't write out commit record.
313 * If we get an error, just continue and give back the log ticket.
314 */
315 (((ticket->t_flags & XLOG_TIC_INITED) == 0) &&
316 (xlog_commit_record(mp, ticket,
317 (xlog_in_core_t **)iclog, &lsn)))) {
318 lsn = (xfs_lsn_t) -1;
319 if (ticket->t_flags & XLOG_TIC_PERM_RESERV) {
320 flags |= XFS_LOG_REL_PERM_RESERV;
321 }
322 }
323
324
325 if ((ticket->t_flags & XLOG_TIC_PERM_RESERV) == 0 ||
326 (flags & XFS_LOG_REL_PERM_RESERV)) {
327 /*
Nathan Scottc41564b2006-03-29 08:55:14 +1000328 * Release ticket if not permanent reservation or a specific
Linus Torvalds1da177e2005-04-16 15:20:36 -0700329 * request has been made to release a permanent reservation.
330 */
Tim Shimmin7e9c6392005-09-02 16:42:05 +1000331 xlog_trace_loggrant(log, ticket, "xfs_log_done: (non-permanent)");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700332 xlog_ungrant_log_space(log, ticket);
333 xlog_state_put_ticket(log, ticket);
334 } else {
Tim Shimmin7e9c6392005-09-02 16:42:05 +1000335 xlog_trace_loggrant(log, ticket, "xfs_log_done: (permanent)");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700336 xlog_regrant_reserve_log_space(log, ticket);
337 }
338
339 /* If this ticket was a permanent reservation and we aren't
340 * trying to release it, reset the inited flags; so next time
341 * we write, a start record will be written out.
342 */
343 if ((ticket->t_flags & XLOG_TIC_PERM_RESERV) &&
344 (flags & XFS_LOG_REL_PERM_RESERV) == 0)
345 ticket->t_flags |= XLOG_TIC_INITED;
346
347 return lsn;
348} /* xfs_log_done */
349
350
351/*
352 * Force the in-core log to disk. If flags == XFS_LOG_SYNC,
353 * the force is done synchronously.
354 *
355 * Asynchronous forces are implemented by setting the WANT_SYNC
356 * bit in the appropriate in-core log and then returning.
357 *
358 * Synchronous forces are implemented with a semaphore. All callers
359 * to force a given lsn to disk will wait on a semaphore attached to the
360 * specific in-core log. When given in-core log finally completes its
361 * write to disk, that thread will wake up all threads waiting on the
362 * semaphore.
363 */
364int
Christoph Hellwigf538d4d2005-11-02 10:26:59 +1100365_xfs_log_force(
366 xfs_mount_t *mp,
367 xfs_lsn_t lsn,
368 uint flags,
369 int *log_flushed)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700370{
Christoph Hellwigf538d4d2005-11-02 10:26:59 +1100371 xlog_t *log = mp->m_log;
372 int dummy;
373
374 if (!log_flushed)
375 log_flushed = &dummy;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700376
Linus Torvalds1da177e2005-04-16 15:20:36 -0700377 ASSERT(flags & XFS_LOG_FORCE);
378
379 XFS_STATS_INC(xs_log_force);
380
Christoph Hellwigf538d4d2005-11-02 10:26:59 +1100381 if (log->l_flags & XLOG_IO_ERROR)
382 return XFS_ERROR(EIO);
383 if (lsn == 0)
384 return xlog_state_sync_all(log, flags, log_flushed);
385 else
386 return xlog_state_sync(log, lsn, flags, log_flushed);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700387} /* xfs_log_force */
388
389/*
390 * Attaches a new iclog I/O completion callback routine during
391 * transaction commit. If the log is in error state, a non-zero
392 * return code is handed back and the caller is responsible for
393 * executing the callback at an appropriate time.
394 */
395int
396xfs_log_notify(xfs_mount_t *mp, /* mount of partition */
397 void *iclog_hndl, /* iclog to hang callback off */
398 xfs_log_callback_t *cb)
399{
400 xlog_t *log = mp->m_log;
401 xlog_in_core_t *iclog = (xlog_in_core_t *)iclog_hndl;
402 int abortflg, spl;
403
Linus Torvalds1da177e2005-04-16 15:20:36 -0700404 cb->cb_next = NULL;
405 spl = LOG_LOCK(log);
406 abortflg = (iclog->ic_state & XLOG_STATE_IOERROR);
407 if (!abortflg) {
408 ASSERT_ALWAYS((iclog->ic_state == XLOG_STATE_ACTIVE) ||
409 (iclog->ic_state == XLOG_STATE_WANT_SYNC));
410 cb->cb_next = NULL;
411 *(iclog->ic_callback_tail) = cb;
412 iclog->ic_callback_tail = &(cb->cb_next);
413 }
414 LOG_UNLOCK(log, spl);
415 return abortflg;
416} /* xfs_log_notify */
417
418int
419xfs_log_release_iclog(xfs_mount_t *mp,
420 void *iclog_hndl)
421{
422 xlog_t *log = mp->m_log;
423 xlog_in_core_t *iclog = (xlog_in_core_t *)iclog_hndl;
424
425 if (xlog_state_release_iclog(log, iclog)) {
Nathan Scott7d04a332006-06-09 14:58:38 +1000426 xfs_force_shutdown(mp, SHUTDOWN_LOG_IO_ERROR);
Jesper Juhl014c2542006-01-15 02:37:08 +0100427 return EIO;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700428 }
429
430 return 0;
431}
432
433/*
434 * 1. Reserve an amount of on-disk log space and return a ticket corresponding
435 * to the reservation.
436 * 2. Potentially, push buffers at tail of log to disk.
437 *
438 * Each reservation is going to reserve extra space for a log record header.
439 * When writes happen to the on-disk log, we don't subtract the length of the
440 * log record header from any reservation. By wasting space in each
441 * reservation, we prevent over allocation problems.
442 */
443int
444xfs_log_reserve(xfs_mount_t *mp,
445 int unit_bytes,
446 int cnt,
447 xfs_log_ticket_t *ticket,
448 __uint8_t client,
Tim Shimmin7e9c6392005-09-02 16:42:05 +1000449 uint flags,
450 uint t_type)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700451{
452 xlog_t *log = mp->m_log;
453 xlog_ticket_t *internal_ticket;
Nathan Scottcfcbbbd2005-11-02 15:12:04 +1100454 int retval = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700455
Linus Torvalds1da177e2005-04-16 15:20:36 -0700456 ASSERT(client == XFS_TRANSACTION || client == XFS_LOG);
457 ASSERT((flags & XFS_LOG_NOSLEEP) == 0);
458
459 if (XLOG_FORCED_SHUTDOWN(log))
460 return XFS_ERROR(EIO);
461
462 XFS_STATS_INC(xs_try_logspace);
463
464 if (*ticket != NULL) {
465 ASSERT(flags & XFS_LOG_PERM_RESERV);
466 internal_ticket = (xlog_ticket_t *)*ticket;
Tim Shimmin7e9c6392005-09-02 16:42:05 +1000467 xlog_trace_loggrant(log, internal_ticket, "xfs_log_reserve: existing ticket (permanent trans)");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700468 xlog_grant_push_ail(mp, internal_ticket->t_unit_res);
469 retval = xlog_regrant_write_log_space(log, internal_ticket);
470 } else {
471 /* may sleep if need to allocate more tickets */
472 internal_ticket = xlog_ticket_get(log, unit_bytes, cnt,
473 client, flags);
Tim Shimmin7e9c6392005-09-02 16:42:05 +1000474 internal_ticket->t_trans_type = t_type;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700475 *ticket = internal_ticket;
Tim Shimmin7e9c6392005-09-02 16:42:05 +1000476 xlog_trace_loggrant(log, internal_ticket,
477 (internal_ticket->t_flags & XLOG_TIC_PERM_RESERV) ?
478 "xfs_log_reserve: create new ticket (permanent trans)" :
479 "xfs_log_reserve: create new ticket");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700480 xlog_grant_push_ail(mp,
481 (internal_ticket->t_unit_res *
482 internal_ticket->t_cnt));
483 retval = xlog_grant_log_space(log, internal_ticket);
484 }
485
486 return retval;
487} /* xfs_log_reserve */
488
489
490/*
491 * Mount a log filesystem
492 *
493 * mp - ubiquitous xfs mount point structure
494 * log_target - buftarg of on-disk log device
495 * blk_offset - Start block # where block size is 512 bytes (BBSIZE)
496 * num_bblocks - Number of BBSIZE blocks in on-disk log
497 *
498 * Return error or zero.
499 */
500int
501xfs_log_mount(xfs_mount_t *mp,
502 xfs_buftarg_t *log_target,
503 xfs_daddr_t blk_offset,
504 int num_bblks)
505{
506 if (!(mp->m_flags & XFS_MOUNT_NORECOVERY))
507 cmn_err(CE_NOTE, "XFS mounting filesystem %s", mp->m_fsname);
508 else {
509 cmn_err(CE_NOTE,
510 "!Mounting filesystem \"%s\" in no-recovery mode. Filesystem will be inconsistent.",
511 mp->m_fsname);
Christoph Hellwigbd186aa2007-08-30 17:21:12 +1000512 ASSERT(mp->m_flags & XFS_MOUNT_RDONLY);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700513 }
514
515 mp->m_log = xlog_alloc_log(mp, log_target, blk_offset, num_bblks);
516
Linus Torvalds1da177e2005-04-16 15:20:36 -0700517 /*
518 * skip log recovery on a norecovery mount. pretend it all
519 * just worked.
520 */
521 if (!(mp->m_flags & XFS_MOUNT_NORECOVERY)) {
Christoph Hellwigbd186aa2007-08-30 17:21:12 +1000522 int error, readonly = (mp->m_flags & XFS_MOUNT_RDONLY);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700523
524 if (readonly)
Christoph Hellwigbd186aa2007-08-30 17:21:12 +1000525 mp->m_flags &= ~XFS_MOUNT_RDONLY;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700526
Eric Sandeen65be6052006-01-11 15:34:19 +1100527 error = xlog_recover(mp->m_log);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700528
529 if (readonly)
Christoph Hellwigbd186aa2007-08-30 17:21:12 +1000530 mp->m_flags |= XFS_MOUNT_RDONLY;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700531 if (error) {
532 cmn_err(CE_WARN, "XFS: log mount/recovery failed: error %d", error);
Nathan Scottc41564b2006-03-29 08:55:14 +1000533 xlog_dealloc_log(mp->m_log);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700534 return error;
535 }
536 }
537
538 /* Normal transactions can now occur */
539 mp->m_log->l_flags &= ~XLOG_ACTIVE_RECOVERY;
540
541 /* End mounting message in xfs_log_mount_finish */
542 return 0;
543} /* xfs_log_mount */
544
545/*
546 * Finish the recovery of the file system. This is separate from
547 * the xfs_log_mount() call, because it depends on the code in
548 * xfs_mountfs() to read in the root and real-time bitmap inodes
549 * between calling xfs_log_mount() and here.
550 *
551 * mp - ubiquitous xfs mount point structure
552 */
553int
554xfs_log_mount_finish(xfs_mount_t *mp, int mfsi_flags)
555{
556 int error;
557
558 if (!(mp->m_flags & XFS_MOUNT_NORECOVERY))
559 error = xlog_recover_finish(mp->m_log, mfsi_flags);
560 else {
561 error = 0;
Christoph Hellwigbd186aa2007-08-30 17:21:12 +1000562 ASSERT(mp->m_flags & XFS_MOUNT_RDONLY);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700563 }
564
565 return error;
566}
567
568/*
569 * Unmount processing for the log.
570 */
571int
572xfs_log_unmount(xfs_mount_t *mp)
573{
574 int error;
575
576 error = xfs_log_unmount_write(mp);
577 xfs_log_unmount_dealloc(mp);
Jesper Juhl014c2542006-01-15 02:37:08 +0100578 return error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700579}
580
581/*
582 * Final log writes as part of unmount.
583 *
584 * Mark the filesystem clean as unmount happens. Note that during relocation
585 * this routine needs to be executed as part of source-bag while the
586 * deallocation must not be done until source-end.
587 */
588
589/*
590 * Unmount record used to have a string "Unmount filesystem--" in the
591 * data section where the "Un" was really a magic number (XLOG_UNMOUNT_TYPE).
592 * We just write the magic number now since that particular field isn't
593 * currently architecture converted and "nUmount" is a bit foo.
594 * As far as I know, there weren't any dependencies on the old behaviour.
595 */
596
597int
598xfs_log_unmount_write(xfs_mount_t *mp)
599{
600 xlog_t *log = mp->m_log;
601 xlog_in_core_t *iclog;
602#ifdef DEBUG
603 xlog_in_core_t *first_iclog;
604#endif
605 xfs_log_iovec_t reg[1];
606 xfs_log_ticket_t tic = NULL;
607 xfs_lsn_t lsn;
608 int error;
609 SPLDECL(s);
610
611 /* the data section must be 32 bit size aligned */
612 struct {
613 __uint16_t magic;
614 __uint16_t pad1;
615 __uint32_t pad2; /* may as well make it 64 bits */
616 } magic = { XLOG_UNMOUNT_TYPE, 0, 0 };
617
Linus Torvalds1da177e2005-04-16 15:20:36 -0700618 /*
619 * Don't write out unmount record on read-only mounts.
620 * Or, if we are doing a forced umount (typically because of IO errors).
621 */
Christoph Hellwigbd186aa2007-08-30 17:21:12 +1000622 if (mp->m_flags & XFS_MOUNT_RDONLY)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700623 return 0;
624
625 xfs_log_force(mp, 0, XFS_LOG_FORCE|XFS_LOG_SYNC);
626
627#ifdef DEBUG
628 first_iclog = iclog = log->l_iclog;
629 do {
630 if (!(iclog->ic_state & XLOG_STATE_IOERROR)) {
631 ASSERT(iclog->ic_state & XLOG_STATE_ACTIVE);
632 ASSERT(iclog->ic_offset == 0);
633 }
634 iclog = iclog->ic_next;
635 } while (iclog != first_iclog);
636#endif
637 if (! (XLOG_FORCED_SHUTDOWN(log))) {
638 reg[0].i_addr = (void*)&magic;
639 reg[0].i_len = sizeof(magic);
Tim Shimmin7e9c6392005-09-02 16:42:05 +1000640 XLOG_VEC_SET_TYPE(&reg[0], XLOG_REG_TYPE_UNMOUNT);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700641
Tim Shimmin955e47a2006-09-28 11:04:16 +1000642 error = xfs_log_reserve(mp, 600, 1, &tic,
643 XFS_LOG, 0, XLOG_UNMOUNT_REC_TYPE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700644 if (!error) {
645 /* remove inited flag */
646 ((xlog_ticket_t *)tic)->t_flags = 0;
647 error = xlog_write(mp, reg, 1, tic, &lsn,
648 NULL, XLOG_UNMOUNT_TRANS);
649 /*
650 * At this point, we're umounting anyway,
651 * so there's no point in transitioning log state
652 * to IOERROR. Just continue...
653 */
654 }
655
656 if (error) {
657 xfs_fs_cmn_err(CE_ALERT, mp,
658 "xfs_log_unmount: unmount record failed");
659 }
660
661
662 s = LOG_LOCK(log);
663 iclog = log->l_iclog;
664 iclog->ic_refcnt++;
665 LOG_UNLOCK(log, s);
666 xlog_state_want_sync(log, iclog);
667 (void) xlog_state_release_iclog(log, iclog);
668
669 s = LOG_LOCK(log);
670 if (!(iclog->ic_state == XLOG_STATE_ACTIVE ||
671 iclog->ic_state == XLOG_STATE_DIRTY)) {
672 if (!XLOG_FORCED_SHUTDOWN(log)) {
673 sv_wait(&iclog->ic_forcesema, PMEM,
674 &log->l_icloglock, s);
675 } else {
676 LOG_UNLOCK(log, s);
677 }
678 } else {
679 LOG_UNLOCK(log, s);
680 }
Tim Shimmin955e47a2006-09-28 11:04:16 +1000681 if (tic) {
682 xlog_trace_loggrant(log, tic, "unmount rec");
683 xlog_ungrant_log_space(log, tic);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700684 xlog_state_put_ticket(log, tic);
Tim Shimmin955e47a2006-09-28 11:04:16 +1000685 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700686 } else {
687 /*
688 * We're already in forced_shutdown mode, couldn't
689 * even attempt to write out the unmount transaction.
690 *
691 * Go through the motions of sync'ing and releasing
692 * the iclog, even though no I/O will actually happen,
Nathan Scottc41564b2006-03-29 08:55:14 +1000693 * we need to wait for other log I/Os that may already
Linus Torvalds1da177e2005-04-16 15:20:36 -0700694 * be in progress. Do this as a separate section of
695 * code so we'll know if we ever get stuck here that
696 * we're in this odd situation of trying to unmount
697 * a file system that went into forced_shutdown as
698 * the result of an unmount..
699 */
700 s = LOG_LOCK(log);
701 iclog = log->l_iclog;
702 iclog->ic_refcnt++;
703 LOG_UNLOCK(log, s);
704
705 xlog_state_want_sync(log, iclog);
706 (void) xlog_state_release_iclog(log, iclog);
707
708 s = LOG_LOCK(log);
709
710 if ( ! ( iclog->ic_state == XLOG_STATE_ACTIVE
711 || iclog->ic_state == XLOG_STATE_DIRTY
712 || iclog->ic_state == XLOG_STATE_IOERROR) ) {
713
714 sv_wait(&iclog->ic_forcesema, PMEM,
715 &log->l_icloglock, s);
716 } else {
717 LOG_UNLOCK(log, s);
718 }
719 }
720
721 return 0;
722} /* xfs_log_unmount_write */
723
724/*
725 * Deallocate log structures for unmount/relocation.
726 */
727void
728xfs_log_unmount_dealloc(xfs_mount_t *mp)
729{
Nathan Scottc41564b2006-03-29 08:55:14 +1000730 xlog_dealloc_log(mp->m_log);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700731}
732
733/*
734 * Write region vectors to log. The write happens using the space reservation
735 * of the ticket (tic). It is not a requirement that all writes for a given
736 * transaction occur with one call to xfs_log_write().
737 */
738int
739xfs_log_write(xfs_mount_t * mp,
740 xfs_log_iovec_t reg[],
741 int nentries,
742 xfs_log_ticket_t tic,
743 xfs_lsn_t *start_lsn)
744{
745 int error;
746 xlog_t *log = mp->m_log;
747
Linus Torvalds1da177e2005-04-16 15:20:36 -0700748 if (XLOG_FORCED_SHUTDOWN(log))
749 return XFS_ERROR(EIO);
750
751 if ((error = xlog_write(mp, reg, nentries, tic, start_lsn, NULL, 0))) {
Nathan Scott7d04a332006-06-09 14:58:38 +1000752 xfs_force_shutdown(mp, SHUTDOWN_LOG_IO_ERROR);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700753 }
Jesper Juhl014c2542006-01-15 02:37:08 +0100754 return error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700755} /* xfs_log_write */
756
757
758void
759xfs_log_move_tail(xfs_mount_t *mp,
760 xfs_lsn_t tail_lsn)
761{
762 xlog_ticket_t *tic;
763 xlog_t *log = mp->m_log;
764 int need_bytes, free_bytes, cycle, bytes;
765 SPLDECL(s);
766
Linus Torvalds1da177e2005-04-16 15:20:36 -0700767 if (XLOG_FORCED_SHUTDOWN(log))
768 return;
769 ASSERT(!XFS_FORCED_SHUTDOWN(mp));
770
771 if (tail_lsn == 0) {
772 /* needed since sync_lsn is 64 bits */
773 s = LOG_LOCK(log);
774 tail_lsn = log->l_last_sync_lsn;
775 LOG_UNLOCK(log, s);
776 }
777
778 s = GRANT_LOCK(log);
779
780 /* Also an invalid lsn. 1 implies that we aren't passing in a valid
781 * tail_lsn.
782 */
783 if (tail_lsn != 1) {
784 log->l_tail_lsn = tail_lsn;
785 }
786
787 if ((tic = log->l_write_headq)) {
788#ifdef DEBUG
789 if (log->l_flags & XLOG_ACTIVE_RECOVERY)
790 panic("Recovery problem");
791#endif
792 cycle = log->l_grant_write_cycle;
793 bytes = log->l_grant_write_bytes;
794 free_bytes = xlog_space_left(log, cycle, bytes);
795 do {
796 ASSERT(tic->t_flags & XLOG_TIC_PERM_RESERV);
797
798 if (free_bytes < tic->t_unit_res && tail_lsn != 1)
799 break;
800 tail_lsn = 0;
801 free_bytes -= tic->t_unit_res;
802 sv_signal(&tic->t_sema);
803 tic = tic->t_next;
804 } while (tic != log->l_write_headq);
805 }
806 if ((tic = log->l_reserve_headq)) {
807#ifdef DEBUG
808 if (log->l_flags & XLOG_ACTIVE_RECOVERY)
809 panic("Recovery problem");
810#endif
811 cycle = log->l_grant_reserve_cycle;
812 bytes = log->l_grant_reserve_bytes;
813 free_bytes = xlog_space_left(log, cycle, bytes);
814 do {
815 if (tic->t_flags & XLOG_TIC_PERM_RESERV)
816 need_bytes = tic->t_unit_res*tic->t_cnt;
817 else
818 need_bytes = tic->t_unit_res;
819 if (free_bytes < need_bytes && tail_lsn != 1)
820 break;
821 tail_lsn = 0;
822 free_bytes -= need_bytes;
823 sv_signal(&tic->t_sema);
824 tic = tic->t_next;
825 } while (tic != log->l_reserve_headq);
826 }
827 GRANT_UNLOCK(log, s);
828} /* xfs_log_move_tail */
829
830/*
831 * Determine if we have a transaction that has gone to disk
832 * that needs to be covered. Log activity needs to be idle (no AIL and
833 * nothing in the iclogs). And, we need to be in the right state indicating
834 * something has gone out.
835 */
836int
837xfs_log_need_covered(xfs_mount_t *mp)
838{
839 SPLDECL(s);
840 int needed = 0, gen;
841 xlog_t *log = mp->m_log;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700842
David Chinner92821e22007-05-24 15:26:31 +1000843 if (!xfs_fs_writable(mp))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700844 return 0;
845
846 s = LOG_LOCK(log);
847 if (((log->l_covered_state == XLOG_STATE_COVER_NEED) ||
848 (log->l_covered_state == XLOG_STATE_COVER_NEED2))
849 && !xfs_trans_first_ail(mp, &gen)
850 && xlog_iclogs_empty(log)) {
851 if (log->l_covered_state == XLOG_STATE_COVER_NEED)
852 log->l_covered_state = XLOG_STATE_COVER_DONE;
853 else {
854 ASSERT(log->l_covered_state == XLOG_STATE_COVER_NEED2);
855 log->l_covered_state = XLOG_STATE_COVER_DONE2;
856 }
857 needed = 1;
858 }
859 LOG_UNLOCK(log, s);
Jesper Juhl014c2542006-01-15 02:37:08 +0100860 return needed;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700861}
862
863/******************************************************************************
864 *
865 * local routines
866 *
867 ******************************************************************************
868 */
869
870/* xfs_trans_tail_ail returns 0 when there is nothing in the list.
871 * The log manager must keep track of the last LR which was committed
872 * to disk. The lsn of this LR will become the new tail_lsn whenever
873 * xfs_trans_tail_ail returns 0. If we don't do this, we run into
874 * the situation where stuff could be written into the log but nothing
875 * was ever in the AIL when asked. Eventually, we panic since the
876 * tail hits the head.
877 *
878 * We may be holding the log iclog lock upon entering this routine.
879 */
880xfs_lsn_t
881xlog_assign_tail_lsn(xfs_mount_t *mp)
882{
883 xfs_lsn_t tail_lsn;
884 SPLDECL(s);
885 xlog_t *log = mp->m_log;
886
887 tail_lsn = xfs_trans_tail_ail(mp);
888 s = GRANT_LOCK(log);
889 if (tail_lsn != 0) {
890 log->l_tail_lsn = tail_lsn;
891 } else {
892 tail_lsn = log->l_tail_lsn = log->l_last_sync_lsn;
893 }
894 GRANT_UNLOCK(log, s);
895
896 return tail_lsn;
897} /* xlog_assign_tail_lsn */
898
899
900/*
901 * Return the space in the log between the tail and the head. The head
902 * is passed in the cycle/bytes formal parms. In the special case where
903 * the reserve head has wrapped passed the tail, this calculation is no
904 * longer valid. In this case, just return 0 which means there is no space
905 * in the log. This works for all places where this function is called
906 * with the reserve head. Of course, if the write head were to ever
907 * wrap the tail, we should blow up. Rather than catch this case here,
908 * we depend on other ASSERTions in other parts of the code. XXXmiken
909 *
910 * This code also handles the case where the reservation head is behind
911 * the tail. The details of this case are described below, but the end
912 * result is that we return the size of the log as the amount of space left.
913 */
914int
915xlog_space_left(xlog_t *log, int cycle, int bytes)
916{
917 int free_bytes;
918 int tail_bytes;
919 int tail_cycle;
920
921 tail_bytes = BBTOB(BLOCK_LSN(log->l_tail_lsn));
922 tail_cycle = CYCLE_LSN(log->l_tail_lsn);
923 if ((tail_cycle == cycle) && (bytes >= tail_bytes)) {
924 free_bytes = log->l_logsize - (bytes - tail_bytes);
925 } else if ((tail_cycle + 1) < cycle) {
926 return 0;
927 } else if (tail_cycle < cycle) {
928 ASSERT(tail_cycle == (cycle - 1));
929 free_bytes = tail_bytes - bytes;
930 } else {
931 /*
932 * The reservation head is behind the tail.
933 * In this case we just want to return the size of the
934 * log as the amount of space left.
935 */
936 xfs_fs_cmn_err(CE_ALERT, log->l_mp,
937 "xlog_space_left: head behind tail\n"
938 " tail_cycle = %d, tail_bytes = %d\n"
939 " GH cycle = %d, GH bytes = %d",
940 tail_cycle, tail_bytes, cycle, bytes);
941 ASSERT(0);
942 free_bytes = log->l_logsize;
943 }
944 return free_bytes;
945} /* xlog_space_left */
946
947
948/*
949 * Log function which is called when an io completes.
950 *
951 * The log manager needs its own routine, in order to control what
952 * happens with the buffer after the write completes.
953 */
954void
955xlog_iodone(xfs_buf_t *bp)
956{
957 xlog_in_core_t *iclog;
958 xlog_t *l;
959 int aborted;
960
961 iclog = XFS_BUF_FSPRIVATE(bp, xlog_in_core_t *);
962 ASSERT(XFS_BUF_FSPRIVATE2(bp, unsigned long) == (unsigned long) 2);
963 XFS_BUF_SET_FSPRIVATE2(bp, (unsigned long)1);
964 aborted = 0;
965
966 /*
967 * Some versions of cpp barf on the recursive definition of
968 * ic_log -> hic_fields.ic_log and expand ic_log twice when
969 * it is passed through two macros. Workaround broken cpp.
970 */
971 l = iclog->ic_log;
972
973 /*
David Chinner0bfefc42007-05-14 18:24:23 +1000974 * If the ordered flag has been removed by a lower
975 * layer, it means the underlyin device no longer supports
976 * barrier I/O. Warn loudly and turn off barriers.
977 */
978 if ((l->l_mp->m_flags & XFS_MOUNT_BARRIER) && !XFS_BUF_ORDERED(bp)) {
979 l->l_mp->m_flags &= ~XFS_MOUNT_BARRIER;
980 xfs_fs_cmn_err(CE_WARN, l->l_mp,
981 "xlog_iodone: Barriers are no longer supported"
982 " by device. Disabling barriers\n");
983 xfs_buftrace("XLOG_IODONE BARRIERS OFF", bp);
984 }
985
986 /*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700987 * Race to shutdown the filesystem if we see an error.
988 */
989 if (XFS_TEST_ERROR((XFS_BUF_GETERROR(bp)), l->l_mp,
990 XFS_ERRTAG_IODONE_IOERR, XFS_RANDOM_IODONE_IOERR)) {
991 xfs_ioerror_alert("xlog_iodone", l->l_mp, bp, XFS_BUF_ADDR(bp));
992 XFS_BUF_STALE(bp);
Nathan Scott7d04a332006-06-09 14:58:38 +1000993 xfs_force_shutdown(l->l_mp, SHUTDOWN_LOG_IO_ERROR);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700994 /*
995 * This flag will be propagated to the trans-committed
996 * callback routines to let them know that the log-commit
997 * didn't succeed.
998 */
999 aborted = XFS_LI_ABORTED;
1000 } else if (iclog->ic_state & XLOG_STATE_IOERROR) {
1001 aborted = XFS_LI_ABORTED;
1002 }
David Chinner3db296f2007-05-14 18:24:16 +10001003
1004 /* log I/O is always issued ASYNC */
1005 ASSERT(XFS_BUF_ISASYNC(bp));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001006 xlog_state_done_syncing(iclog, aborted);
David Chinner3db296f2007-05-14 18:24:16 +10001007 /*
1008 * do not reference the buffer (bp) here as we could race
1009 * with it being freed after writing the unmount record to the
1010 * log.
1011 */
1012
Linus Torvalds1da177e2005-04-16 15:20:36 -07001013} /* xlog_iodone */
1014
1015/*
1016 * The bdstrat callback function for log bufs. This gives us a central
1017 * place to trap bufs in case we get hit by a log I/O error and need to
1018 * shutdown. Actually, in practice, even when we didn't get a log error,
1019 * we transition the iclogs to IOERROR state *after* flushing all existing
1020 * iclogs to disk. This is because we don't want anymore new transactions to be
1021 * started or completed afterwards.
1022 */
1023STATIC int
1024xlog_bdstrat_cb(struct xfs_buf *bp)
1025{
1026 xlog_in_core_t *iclog;
1027
1028 iclog = XFS_BUF_FSPRIVATE(bp, xlog_in_core_t *);
1029
1030 if ((iclog->ic_state & XLOG_STATE_IOERROR) == 0) {
1031 /* note for irix bstrat will need struct bdevsw passed
1032 * Fix the following macro if the code ever is merged
1033 */
1034 XFS_bdstrat(bp);
1035 return 0;
1036 }
1037
1038 xfs_buftrace("XLOG__BDSTRAT IOERROR", bp);
1039 XFS_BUF_ERROR(bp, EIO);
1040 XFS_BUF_STALE(bp);
1041 xfs_biodone(bp);
Jesper Juhl014c2542006-01-15 02:37:08 +01001042 return XFS_ERROR(EIO);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001043
1044
1045}
1046
1047/*
1048 * Return size of each in-core log record buffer.
1049 *
Eric Sandeen1cb51252007-08-16 16:24:43 +10001050 * All machines get 8 x 32KB buffers by default, unless tuned otherwise.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001051 *
1052 * If the filesystem blocksize is too large, we may need to choose a
1053 * larger size since the directory code currently logs entire blocks.
1054 */
1055
1056STATIC void
1057xlog_get_iclog_buffer_size(xfs_mount_t *mp,
1058 xlog_t *log)
1059{
1060 int size;
1061 int xhdrs;
1062
Eric Sandeen1cb51252007-08-16 16:24:43 +10001063 if (mp->m_logbufs <= 0)
1064 log->l_iclog_bufs = XLOG_MAX_ICLOGS;
1065 else
Nathan Scottcfcbbbd2005-11-02 15:12:04 +11001066 log->l_iclog_bufs = mp->m_logbufs;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001067
1068 /*
1069 * Buffer size passed in from mount system call.
1070 */
Nathan Scottcfcbbbd2005-11-02 15:12:04 +11001071 if (mp->m_logbsize > 0) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001072 size = log->l_iclog_size = mp->m_logbsize;
1073 log->l_iclog_size_log = 0;
1074 while (size != 1) {
1075 log->l_iclog_size_log++;
1076 size >>= 1;
1077 }
1078
1079 if (XFS_SB_VERSION_HASLOGV2(&mp->m_sb)) {
1080 /* # headers = size / 32K
1081 * one header holds cycles from 32K of data
1082 */
1083
1084 xhdrs = mp->m_logbsize / XLOG_HEADER_CYCLE_SIZE;
1085 if (mp->m_logbsize % XLOG_HEADER_CYCLE_SIZE)
1086 xhdrs++;
1087 log->l_iclog_hsize = xhdrs << BBSHIFT;
1088 log->l_iclog_heads = xhdrs;
1089 } else {
1090 ASSERT(mp->m_logbsize <= XLOG_BIG_RECORD_BSIZE);
1091 log->l_iclog_hsize = BBSIZE;
1092 log->l_iclog_heads = 1;
1093 }
Nathan Scottcfcbbbd2005-11-02 15:12:04 +11001094 goto done;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001095 }
1096
Eric Sandeen1cb51252007-08-16 16:24:43 +10001097 /* All machines use 32KB buffers by default. */
1098 log->l_iclog_size = XLOG_BIG_RECORD_BSIZE;
1099 log->l_iclog_size_log = XLOG_BIG_RECORD_BSHIFT;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001100
1101 /* the default log size is 16k or 32k which is one header sector */
1102 log->l_iclog_hsize = BBSIZE;
1103 log->l_iclog_heads = 1;
1104
1105 /*
1106 * For 16KB, we use 3 32KB buffers. For 32KB block sizes, we use
1107 * 4 32KB buffers. For 64KB block sizes, we use 8 32KB buffers.
1108 */
1109 if (mp->m_sb.sb_blocksize >= 16*1024) {
1110 log->l_iclog_size = XLOG_BIG_RECORD_BSIZE;
1111 log->l_iclog_size_log = XLOG_BIG_RECORD_BSHIFT;
Nathan Scottcfcbbbd2005-11-02 15:12:04 +11001112 if (mp->m_logbufs <= 0) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001113 switch (mp->m_sb.sb_blocksize) {
1114 case 16*1024: /* 16 KB */
1115 log->l_iclog_bufs = 3;
1116 break;
1117 case 32*1024: /* 32 KB */
1118 log->l_iclog_bufs = 4;
1119 break;
1120 case 64*1024: /* 64 KB */
1121 log->l_iclog_bufs = 8;
1122 break;
1123 default:
1124 xlog_panic("XFS: Invalid blocksize");
1125 break;
1126 }
1127 }
1128 }
Nathan Scottcfcbbbd2005-11-02 15:12:04 +11001129
1130done: /* are we being asked to make the sizes selected above visible? */
1131 if (mp->m_logbufs == 0)
1132 mp->m_logbufs = log->l_iclog_bufs;
1133 if (mp->m_logbsize == 0)
1134 mp->m_logbsize = log->l_iclog_size;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001135} /* xlog_get_iclog_buffer_size */
1136
1137
1138/*
1139 * This routine initializes some of the log structure for a given mount point.
1140 * Its primary purpose is to fill in enough, so recovery can occur. However,
1141 * some other stuff may be filled in too.
1142 */
1143STATIC xlog_t *
1144xlog_alloc_log(xfs_mount_t *mp,
1145 xfs_buftarg_t *log_target,
1146 xfs_daddr_t blk_offset,
1147 int num_bblks)
1148{
1149 xlog_t *log;
1150 xlog_rec_header_t *head;
1151 xlog_in_core_t **iclogp;
1152 xlog_in_core_t *iclog, *prev_iclog=NULL;
1153 xfs_buf_t *bp;
1154 int i;
1155 int iclogsize;
1156
1157 log = (xlog_t *)kmem_zalloc(sizeof(xlog_t), KM_SLEEP);
1158
1159 log->l_mp = mp;
1160 log->l_targ = log_target;
1161 log->l_logsize = BBTOB(num_bblks);
1162 log->l_logBBstart = blk_offset;
1163 log->l_logBBsize = num_bblks;
1164 log->l_covered_state = XLOG_STATE_COVER_IDLE;
1165 log->l_flags |= XLOG_ACTIVE_RECOVERY;
1166
1167 log->l_prev_block = -1;
1168 ASSIGN_ANY_LSN_HOST(log->l_tail_lsn, 1, 0);
1169 /* log->l_tail_lsn = 0x100000000LL; cycle = 1; current block = 0 */
1170 log->l_last_sync_lsn = log->l_tail_lsn;
1171 log->l_curr_cycle = 1; /* 0 is bad since this is initial value */
1172 log->l_grant_reserve_cycle = 1;
1173 log->l_grant_write_cycle = 1;
1174
1175 if (XFS_SB_VERSION_HASSECTOR(&mp->m_sb)) {
1176 log->l_sectbb_log = mp->m_sb.sb_logsectlog - BBSHIFT;
1177 ASSERT(log->l_sectbb_log <= mp->m_sectbb_log);
1178 /* for larger sector sizes, must have v2 or external log */
1179 ASSERT(log->l_sectbb_log == 0 ||
1180 log->l_logBBstart == 0 ||
1181 XFS_SB_VERSION_HASLOGV2(&mp->m_sb));
1182 ASSERT(mp->m_sb.sb_logsectlog >= BBSHIFT);
1183 }
1184 log->l_sectbb_mask = (1 << log->l_sectbb_log) - 1;
1185
1186 xlog_get_iclog_buffer_size(mp, log);
1187
1188 bp = xfs_buf_get_empty(log->l_iclog_size, mp->m_logdev_targp);
1189 XFS_BUF_SET_IODONE_FUNC(bp, xlog_iodone);
1190 XFS_BUF_SET_BDSTRAT_FUNC(bp, xlog_bdstrat_cb);
1191 XFS_BUF_SET_FSPRIVATE2(bp, (unsigned long)1);
1192 ASSERT(XFS_BUF_ISBUSY(bp));
1193 ASSERT(XFS_BUF_VALUSEMA(bp) <= 0);
1194 log->l_xbuf = bp;
1195
1196 spinlock_init(&log->l_icloglock, "iclog");
1197 spinlock_init(&log->l_grant_lock, "grhead_iclog");
1198 initnsema(&log->l_flushsema, 0, "ic-flush");
1199 xlog_state_ticket_alloc(log); /* wait until after icloglock inited */
1200
1201 /* log record size must be multiple of BBSIZE; see xlog_rec_header_t */
1202 ASSERT((XFS_BUF_SIZE(bp) & BBMASK) == 0);
1203
1204 iclogp = &log->l_iclog;
1205 /*
1206 * The amount of memory to allocate for the iclog structure is
1207 * rather funky due to the way the structure is defined. It is
1208 * done this way so that we can use different sizes for machines
1209 * with different amounts of memory. See the definition of
1210 * xlog_in_core_t in xfs_log_priv.h for details.
1211 */
1212 iclogsize = log->l_iclog_size;
1213 ASSERT(log->l_iclog_size >= 4096);
1214 for (i=0; i < log->l_iclog_bufs; i++) {
1215 *iclogp = (xlog_in_core_t *)
1216 kmem_zalloc(sizeof(xlog_in_core_t), KM_SLEEP);
1217 iclog = *iclogp;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001218 iclog->ic_prev = prev_iclog;
1219 prev_iclog = iclog;
Christoph Hellwig1fa40b02007-05-14 18:23:50 +10001220
1221 bp = xfs_buf_get_noaddr(log->l_iclog_size, mp->m_logdev_targp);
1222 if (!XFS_BUF_CPSEMA(bp))
1223 ASSERT(0);
1224 XFS_BUF_SET_IODONE_FUNC(bp, xlog_iodone);
1225 XFS_BUF_SET_BDSTRAT_FUNC(bp, xlog_bdstrat_cb);
1226 XFS_BUF_SET_FSPRIVATE2(bp, (unsigned long)1);
1227 iclog->ic_bp = bp;
1228 iclog->hic_data = bp->b_addr;
1229
Linus Torvalds1da177e2005-04-16 15:20:36 -07001230 log->l_iclog_bak[i] = (xfs_caddr_t)&(iclog->ic_header);
1231
1232 head = &iclog->ic_header;
1233 memset(head, 0, sizeof(xlog_rec_header_t));
1234 INT_SET(head->h_magicno, ARCH_CONVERT, XLOG_HEADER_MAGIC_NUM);
1235 INT_SET(head->h_version, ARCH_CONVERT,
1236 XFS_SB_VERSION_HASLOGV2(&log->l_mp->m_sb) ? 2 : 1);
1237 INT_SET(head->h_size, ARCH_CONVERT, log->l_iclog_size);
1238 /* new fields */
1239 INT_SET(head->h_fmt, ARCH_CONVERT, XLOG_FMT);
1240 memcpy(&head->h_fs_uuid, &mp->m_sb.sb_uuid, sizeof(uuid_t));
1241
Linus Torvalds1da177e2005-04-16 15:20:36 -07001242
1243 iclog->ic_size = XFS_BUF_SIZE(bp) - log->l_iclog_hsize;
1244 iclog->ic_state = XLOG_STATE_ACTIVE;
1245 iclog->ic_log = log;
1246 iclog->ic_callback_tail = &(iclog->ic_callback);
1247 iclog->ic_datap = (char *)iclog->hic_data + log->l_iclog_hsize;
1248
1249 ASSERT(XFS_BUF_ISBUSY(iclog->ic_bp));
1250 ASSERT(XFS_BUF_VALUSEMA(iclog->ic_bp) <= 0);
1251 sv_init(&iclog->ic_forcesema, SV_DEFAULT, "iclog-force");
1252 sv_init(&iclog->ic_writesema, SV_DEFAULT, "iclog-write");
1253
1254 iclogp = &iclog->ic_next;
1255 }
1256 *iclogp = log->l_iclog; /* complete ring */
1257 log->l_iclog->ic_prev = prev_iclog; /* re-write 1st prev ptr */
1258
1259 return log;
1260} /* xlog_alloc_log */
1261
1262
1263/*
1264 * Write out the commit record of a transaction associated with the given
1265 * ticket. Return the lsn of the commit record.
1266 */
1267STATIC int
1268xlog_commit_record(xfs_mount_t *mp,
1269 xlog_ticket_t *ticket,
1270 xlog_in_core_t **iclog,
1271 xfs_lsn_t *commitlsnp)
1272{
1273 int error;
1274 xfs_log_iovec_t reg[1];
1275
1276 reg[0].i_addr = NULL;
1277 reg[0].i_len = 0;
Tim Shimmin7e9c6392005-09-02 16:42:05 +10001278 XLOG_VEC_SET_TYPE(&reg[0], XLOG_REG_TYPE_COMMIT);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001279
1280 ASSERT_ALWAYS(iclog);
1281 if ((error = xlog_write(mp, reg, 1, ticket, commitlsnp,
1282 iclog, XLOG_COMMIT_TRANS))) {
Nathan Scott7d04a332006-06-09 14:58:38 +10001283 xfs_force_shutdown(mp, SHUTDOWN_LOG_IO_ERROR);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001284 }
Jesper Juhl014c2542006-01-15 02:37:08 +01001285 return error;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001286} /* xlog_commit_record */
1287
1288
1289/*
1290 * Push on the buffer cache code if we ever use more than 75% of the on-disk
1291 * log space. This code pushes on the lsn which would supposedly free up
1292 * the 25% which we want to leave free. We may need to adopt a policy which
1293 * pushes on an lsn which is further along in the log once we reach the high
1294 * water mark. In this manner, we would be creating a low water mark.
1295 */
1296void
1297xlog_grant_push_ail(xfs_mount_t *mp,
1298 int need_bytes)
1299{
1300 xlog_t *log = mp->m_log; /* pointer to the log */
1301 xfs_lsn_t tail_lsn; /* lsn of the log tail */
1302 xfs_lsn_t threshold_lsn = 0; /* lsn we'd like to be at */
1303 int free_blocks; /* free blocks left to write to */
1304 int free_bytes; /* free bytes left to write to */
1305 int threshold_block; /* block in lsn we'd like to be at */
1306 int threshold_cycle; /* lsn cycle we'd like to be at */
1307 int free_threshold;
1308 SPLDECL(s);
1309
1310 ASSERT(BTOBB(need_bytes) < log->l_logBBsize);
1311
1312 s = GRANT_LOCK(log);
1313 free_bytes = xlog_space_left(log,
1314 log->l_grant_reserve_cycle,
1315 log->l_grant_reserve_bytes);
1316 tail_lsn = log->l_tail_lsn;
1317 free_blocks = BTOBBT(free_bytes);
1318
1319 /*
1320 * Set the threshold for the minimum number of free blocks in the
1321 * log to the maximum of what the caller needs, one quarter of the
1322 * log, and 256 blocks.
1323 */
1324 free_threshold = BTOBB(need_bytes);
1325 free_threshold = MAX(free_threshold, (log->l_logBBsize >> 2));
1326 free_threshold = MAX(free_threshold, 256);
1327 if (free_blocks < free_threshold) {
1328 threshold_block = BLOCK_LSN(tail_lsn) + free_threshold;
1329 threshold_cycle = CYCLE_LSN(tail_lsn);
1330 if (threshold_block >= log->l_logBBsize) {
1331 threshold_block -= log->l_logBBsize;
1332 threshold_cycle += 1;
1333 }
1334 ASSIGN_ANY_LSN_HOST(threshold_lsn, threshold_cycle,
1335 threshold_block);
1336
1337 /* Don't pass in an lsn greater than the lsn of the last
1338 * log record known to be on disk.
1339 */
1340 if (XFS_LSN_CMP(threshold_lsn, log->l_last_sync_lsn) > 0)
1341 threshold_lsn = log->l_last_sync_lsn;
1342 }
1343 GRANT_UNLOCK(log, s);
1344
1345 /*
1346 * Get the transaction layer to kick the dirty buffers out to
1347 * disk asynchronously. No point in trying to do this if
1348 * the filesystem is shutting down.
1349 */
1350 if (threshold_lsn &&
1351 !XLOG_FORCED_SHUTDOWN(log))
1352 xfs_trans_push_ail(mp, threshold_lsn);
1353} /* xlog_grant_push_ail */
1354
1355
1356/*
1357 * Flush out the in-core log (iclog) to the on-disk log in an asynchronous
1358 * fashion. Previously, we should have moved the current iclog
1359 * ptr in the log to point to the next available iclog. This allows further
1360 * write to continue while this code syncs out an iclog ready to go.
1361 * Before an in-core log can be written out, the data section must be scanned
1362 * to save away the 1st word of each BBSIZE block into the header. We replace
1363 * it with the current cycle count. Each BBSIZE block is tagged with the
1364 * cycle count because there in an implicit assumption that drives will
1365 * guarantee that entire 512 byte blocks get written at once. In other words,
1366 * we can't have part of a 512 byte block written and part not written. By
1367 * tagging each block, we will know which blocks are valid when recovering
1368 * after an unclean shutdown.
1369 *
1370 * This routine is single threaded on the iclog. No other thread can be in
1371 * this routine with the same iclog. Changing contents of iclog can there-
1372 * fore be done without grabbing the state machine lock. Updating the global
1373 * log will require grabbing the lock though.
1374 *
1375 * The entire log manager uses a logical block numbering scheme. Only
1376 * log_sync (and then only bwrite()) know about the fact that the log may
1377 * not start with block zero on a given device. The log block start offset
1378 * is added immediately before calling bwrite().
1379 */
1380
1381int
1382xlog_sync(xlog_t *log,
1383 xlog_in_core_t *iclog)
1384{
1385 xfs_caddr_t dptr; /* pointer to byte sized element */
1386 xfs_buf_t *bp;
1387 int i, ops;
1388 uint count; /* byte count of bwrite */
1389 uint count_init; /* initial count before roundup */
1390 int roundoff; /* roundoff to BB or stripe */
1391 int split = 0; /* split write into two regions */
1392 int error;
1393 SPLDECL(s);
1394 int v2 = XFS_SB_VERSION_HASLOGV2(&log->l_mp->m_sb);
1395
1396 XFS_STATS_INC(xs_log_writes);
1397 ASSERT(iclog->ic_refcnt == 0);
1398
1399 /* Add for LR header */
1400 count_init = log->l_iclog_hsize + iclog->ic_offset;
1401
1402 /* Round out the log write size */
1403 if (v2 && log->l_mp->m_sb.sb_logsunit > 1) {
1404 /* we have a v2 stripe unit to use */
1405 count = XLOG_LSUNITTOB(log, XLOG_BTOLSUNIT(log, count_init));
1406 } else {
1407 count = BBTOB(BTOBB(count_init));
1408 }
1409 roundoff = count - count_init;
1410 ASSERT(roundoff >= 0);
1411 ASSERT((v2 && log->l_mp->m_sb.sb_logsunit > 1 &&
1412 roundoff < log->l_mp->m_sb.sb_logsunit)
1413 ||
1414 (log->l_mp->m_sb.sb_logsunit <= 1 &&
1415 roundoff < BBTOB(1)));
1416
1417 /* move grant heads by roundoff in sync */
1418 s = GRANT_LOCK(log);
Christoph Hellwigdd954c62006-01-11 15:34:50 +11001419 xlog_grant_add_space(log, roundoff);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001420 GRANT_UNLOCK(log, s);
1421
1422 /* put cycle number in every block */
1423 xlog_pack_data(log, iclog, roundoff);
1424
1425 /* real byte length */
1426 if (v2) {
1427 INT_SET(iclog->ic_header.h_len,
1428 ARCH_CONVERT,
1429 iclog->ic_offset + roundoff);
1430 } else {
1431 INT_SET(iclog->ic_header.h_len, ARCH_CONVERT, iclog->ic_offset);
1432 }
1433
1434 /* put ops count in correct order */
1435 ops = iclog->ic_header.h_num_logops;
1436 INT_SET(iclog->ic_header.h_num_logops, ARCH_CONVERT, ops);
1437
Nathan Scottf5faad72006-07-28 17:04:44 +10001438 bp = iclog->ic_bp;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001439 ASSERT(XFS_BUF_FSPRIVATE2(bp, unsigned long) == (unsigned long)1);
1440 XFS_BUF_SET_FSPRIVATE2(bp, (unsigned long)2);
1441 XFS_BUF_SET_ADDR(bp, BLOCK_LSN(INT_GET(iclog->ic_header.h_lsn, ARCH_CONVERT)));
1442
1443 XFS_STATS_ADD(xs_log_blocks, BTOBB(count));
1444
1445 /* Do we need to split this write into 2 parts? */
1446 if (XFS_BUF_ADDR(bp) + BTOBB(count) > log->l_logBBsize) {
1447 split = count - (BBTOB(log->l_logBBsize - XFS_BUF_ADDR(bp)));
1448 count = BBTOB(log->l_logBBsize - XFS_BUF_ADDR(bp));
1449 iclog->ic_bwritecnt = 2; /* split into 2 writes */
1450 } else {
1451 iclog->ic_bwritecnt = 1;
1452 }
David Chinner511105b2007-05-24 15:21:57 +10001453 XFS_BUF_SET_COUNT(bp, count);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001454 XFS_BUF_SET_FSPRIVATE(bp, iclog); /* save for later */
Nathan Scottf5faad72006-07-28 17:04:44 +10001455 XFS_BUF_ZEROFLAGS(bp);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001456 XFS_BUF_BUSY(bp);
1457 XFS_BUF_ASYNC(bp);
1458 /*
Christoph Hellwigf538d4d2005-11-02 10:26:59 +11001459 * Do an ordered write for the log block.
Nathan Scottf5faad72006-07-28 17:04:44 +10001460 * Its unnecessary to flush the first split block in the log wrap case.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001461 */
Nathan Scottf5faad72006-07-28 17:04:44 +10001462 if (!split && (log->l_mp->m_flags & XFS_MOUNT_BARRIER))
Christoph Hellwigf538d4d2005-11-02 10:26:59 +11001463 XFS_BUF_ORDERED(bp);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001464
1465 ASSERT(XFS_BUF_ADDR(bp) <= log->l_logBBsize-1);
1466 ASSERT(XFS_BUF_ADDR(bp) + BTOBB(count) <= log->l_logBBsize);
1467
1468 xlog_verify_iclog(log, iclog, count, B_TRUE);
1469
1470 /* account for log which doesn't start at block #0 */
1471 XFS_BUF_SET_ADDR(bp, XFS_BUF_ADDR(bp) + log->l_logBBstart);
1472 /*
1473 * Don't call xfs_bwrite here. We do log-syncs even when the filesystem
1474 * is shutting down.
1475 */
1476 XFS_BUF_WRITE(bp);
1477
1478 if ((error = XFS_bwrite(bp))) {
1479 xfs_ioerror_alert("xlog_sync", log->l_mp, bp,
1480 XFS_BUF_ADDR(bp));
Jesper Juhl014c2542006-01-15 02:37:08 +01001481 return error;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001482 }
1483 if (split) {
Nathan Scottf5faad72006-07-28 17:04:44 +10001484 bp = iclog->ic_log->l_xbuf;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001485 ASSERT(XFS_BUF_FSPRIVATE2(bp, unsigned long) ==
1486 (unsigned long)1);
1487 XFS_BUF_SET_FSPRIVATE2(bp, (unsigned long)2);
1488 XFS_BUF_SET_ADDR(bp, 0); /* logical 0 */
1489 XFS_BUF_SET_PTR(bp, (xfs_caddr_t)((__psint_t)&(iclog->ic_header)+
1490 (__psint_t)count), split);
1491 XFS_BUF_SET_FSPRIVATE(bp, iclog);
Nathan Scottf5faad72006-07-28 17:04:44 +10001492 XFS_BUF_ZEROFLAGS(bp);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001493 XFS_BUF_BUSY(bp);
1494 XFS_BUF_ASYNC(bp);
Christoph Hellwigf538d4d2005-11-02 10:26:59 +11001495 if (log->l_mp->m_flags & XFS_MOUNT_BARRIER)
1496 XFS_BUF_ORDERED(bp);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001497 dptr = XFS_BUF_PTR(bp);
1498 /*
1499 * Bump the cycle numbers at the start of each block
1500 * since this part of the buffer is at the start of
1501 * a new cycle. Watch out for the header magic number
1502 * case, though.
1503 */
1504 for (i=0; i<split; i += BBSIZE) {
1505 INT_MOD(*(uint *)dptr, ARCH_CONVERT, +1);
1506 if (INT_GET(*(uint *)dptr, ARCH_CONVERT) == XLOG_HEADER_MAGIC_NUM)
1507 INT_MOD(*(uint *)dptr, ARCH_CONVERT, +1);
1508 dptr += BBSIZE;
1509 }
1510
1511 ASSERT(XFS_BUF_ADDR(bp) <= log->l_logBBsize-1);
1512 ASSERT(XFS_BUF_ADDR(bp) + BTOBB(count) <= log->l_logBBsize);
1513
Nathan Scottc41564b2006-03-29 08:55:14 +10001514 /* account for internal log which doesn't start at block #0 */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001515 XFS_BUF_SET_ADDR(bp, XFS_BUF_ADDR(bp) + log->l_logBBstart);
1516 XFS_BUF_WRITE(bp);
1517 if ((error = XFS_bwrite(bp))) {
1518 xfs_ioerror_alert("xlog_sync (split)", log->l_mp,
1519 bp, XFS_BUF_ADDR(bp));
Jesper Juhl014c2542006-01-15 02:37:08 +01001520 return error;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001521 }
1522 }
Jesper Juhl014c2542006-01-15 02:37:08 +01001523 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001524} /* xlog_sync */
1525
1526
1527/*
Nathan Scottc41564b2006-03-29 08:55:14 +10001528 * Deallocate a log structure
Linus Torvalds1da177e2005-04-16 15:20:36 -07001529 */
1530void
Nathan Scottc41564b2006-03-29 08:55:14 +10001531xlog_dealloc_log(xlog_t *log)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001532{
1533 xlog_in_core_t *iclog, *next_iclog;
1534 xlog_ticket_t *tic, *next_tic;
1535 int i;
1536
1537
1538 iclog = log->l_iclog;
1539 for (i=0; i<log->l_iclog_bufs; i++) {
1540 sv_destroy(&iclog->ic_forcesema);
1541 sv_destroy(&iclog->ic_writesema);
1542 xfs_buf_free(iclog->ic_bp);
1543#ifdef XFS_LOG_TRACE
1544 if (iclog->ic_trace != NULL) {
1545 ktrace_free(iclog->ic_trace);
1546 }
1547#endif
1548 next_iclog = iclog->ic_next;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001549 kmem_free(iclog, sizeof(xlog_in_core_t));
1550 iclog = next_iclog;
1551 }
1552 freesema(&log->l_flushsema);
1553 spinlock_destroy(&log->l_icloglock);
1554 spinlock_destroy(&log->l_grant_lock);
1555
1556 /* XXXsup take a look at this again. */
1557 if ((log->l_ticket_cnt != log->l_ticket_tcnt) &&
1558 !XLOG_FORCED_SHUTDOWN(log)) {
1559 xfs_fs_cmn_err(CE_WARN, log->l_mp,
Nathan Scottc41564b2006-03-29 08:55:14 +10001560 "xlog_dealloc_log: (cnt: %d, total: %d)",
Linus Torvalds1da177e2005-04-16 15:20:36 -07001561 log->l_ticket_cnt, log->l_ticket_tcnt);
1562 /* ASSERT(log->l_ticket_cnt == log->l_ticket_tcnt); */
1563
1564 } else {
1565 tic = log->l_unmount_free;
1566 while (tic) {
1567 next_tic = tic->t_next;
1568 kmem_free(tic, NBPP);
1569 tic = next_tic;
1570 }
1571 }
1572 xfs_buf_free(log->l_xbuf);
1573#ifdef XFS_LOG_TRACE
1574 if (log->l_trace != NULL) {
1575 ktrace_free(log->l_trace);
1576 }
1577 if (log->l_grant_trace != NULL) {
1578 ktrace_free(log->l_grant_trace);
1579 }
1580#endif
1581 log->l_mp->m_log = NULL;
1582 kmem_free(log, sizeof(xlog_t));
Nathan Scottc41564b2006-03-29 08:55:14 +10001583} /* xlog_dealloc_log */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001584
1585/*
1586 * Update counters atomically now that memcpy is done.
1587 */
1588/* ARGSUSED */
1589static inline void
1590xlog_state_finish_copy(xlog_t *log,
1591 xlog_in_core_t *iclog,
1592 int record_cnt,
1593 int copy_bytes)
1594{
1595 SPLDECL(s);
1596
1597 s = LOG_LOCK(log);
1598
1599 iclog->ic_header.h_num_logops += record_cnt;
1600 iclog->ic_offset += copy_bytes;
1601
1602 LOG_UNLOCK(log, s);
1603} /* xlog_state_finish_copy */
1604
1605
1606
1607
1608/*
Tim Shimmin7e9c6392005-09-02 16:42:05 +10001609 * print out info relating to regions written which consume
1610 * the reservation
1611 */
Tim Shimmin7e9c6392005-09-02 16:42:05 +10001612STATIC void
1613xlog_print_tic_res(xfs_mount_t *mp, xlog_ticket_t *ticket)
1614{
1615 uint i;
1616 uint ophdr_spc = ticket->t_res_num_ophdrs * (uint)sizeof(xlog_op_header_t);
1617
1618 /* match with XLOG_REG_TYPE_* in xfs_log.h */
1619 static char *res_type_str[XLOG_REG_TYPE_MAX] = {
1620 "bformat",
1621 "bchunk",
1622 "efi_format",
1623 "efd_format",
1624 "iformat",
1625 "icore",
1626 "iext",
1627 "ibroot",
1628 "ilocal",
1629 "iattr_ext",
1630 "iattr_broot",
1631 "iattr_local",
1632 "qformat",
1633 "dquot",
1634 "quotaoff",
1635 "LR header",
1636 "unmount",
1637 "commit",
1638 "trans header"
1639 };
1640 static char *trans_type_str[XFS_TRANS_TYPE_MAX] = {
1641 "SETATTR_NOT_SIZE",
1642 "SETATTR_SIZE",
1643 "INACTIVE",
1644 "CREATE",
1645 "CREATE_TRUNC",
1646 "TRUNCATE_FILE",
1647 "REMOVE",
1648 "LINK",
1649 "RENAME",
1650 "MKDIR",
1651 "RMDIR",
1652 "SYMLINK",
1653 "SET_DMATTRS",
1654 "GROWFS",
1655 "STRAT_WRITE",
1656 "DIOSTRAT",
1657 "WRITE_SYNC",
1658 "WRITEID",
1659 "ADDAFORK",
1660 "ATTRINVAL",
1661 "ATRUNCATE",
1662 "ATTR_SET",
1663 "ATTR_RM",
1664 "ATTR_FLAG",
1665 "CLEAR_AGI_BUCKET",
1666 "QM_SBCHANGE",
1667 "DUMMY1",
1668 "DUMMY2",
1669 "QM_QUOTAOFF",
1670 "QM_DQALLOC",
1671 "QM_SETQLIM",
1672 "QM_DQCLUSTER",
1673 "QM_QINOCREATE",
1674 "QM_QUOTAOFF_END",
1675 "SB_UNIT",
1676 "FSYNC_TS",
1677 "GROWFSRT_ALLOC",
1678 "GROWFSRT_ZERO",
1679 "GROWFSRT_FREE",
1680 "SWAPEXT"
1681 };
1682
1683 xfs_fs_cmn_err(CE_WARN, mp,
1684 "xfs_log_write: reservation summary:\n"
1685 " trans type = %s (%u)\n"
1686 " unit res = %d bytes\n"
1687 " current res = %d bytes\n"
1688 " total reg = %u bytes (o/flow = %u bytes)\n"
1689 " ophdrs = %u (ophdr space = %u bytes)\n"
1690 " ophdr + reg = %u bytes\n"
1691 " num regions = %u\n",
1692 ((ticket->t_trans_type <= 0 ||
1693 ticket->t_trans_type > XFS_TRANS_TYPE_MAX) ?
1694 "bad-trans-type" : trans_type_str[ticket->t_trans_type-1]),
1695 ticket->t_trans_type,
1696 ticket->t_unit_res,
1697 ticket->t_curr_res,
1698 ticket->t_res_arr_sum, ticket->t_res_o_flow,
1699 ticket->t_res_num_ophdrs, ophdr_spc,
1700 ticket->t_res_arr_sum +
Tim Shimmin12598452006-01-11 21:02:47 +11001701 ticket->t_res_o_flow + ophdr_spc,
Tim Shimmin7e9c6392005-09-02 16:42:05 +10001702 ticket->t_res_num);
1703
1704 for (i = 0; i < ticket->t_res_num; i++) {
Tim Shimmin12598452006-01-11 21:02:47 +11001705 uint r_type = ticket->t_res_arr[i].r_type;
Tim Shimmin7e9c6392005-09-02 16:42:05 +10001706 cmn_err(CE_WARN,
1707 "region[%u]: %s - %u bytes\n",
1708 i,
1709 ((r_type <= 0 || r_type > XLOG_REG_TYPE_MAX) ?
1710 "bad-rtype" : res_type_str[r_type-1]),
1711 ticket->t_res_arr[i].r_len);
1712 }
1713}
Tim Shimmin7e9c6392005-09-02 16:42:05 +10001714
1715/*
Linus Torvalds1da177e2005-04-16 15:20:36 -07001716 * Write some region out to in-core log
1717 *
1718 * This will be called when writing externally provided regions or when
1719 * writing out a commit record for a given transaction.
1720 *
1721 * General algorithm:
1722 * 1. Find total length of this write. This may include adding to the
1723 * lengths passed in.
1724 * 2. Check whether we violate the tickets reservation.
1725 * 3. While writing to this iclog
1726 * A. Reserve as much space in this iclog as can get
1727 * B. If this is first write, save away start lsn
1728 * C. While writing this region:
1729 * 1. If first write of transaction, write start record
1730 * 2. Write log operation header (header per region)
1731 * 3. Find out if we can fit entire region into this iclog
1732 * 4. Potentially, verify destination memcpy ptr
1733 * 5. Memcpy (partial) region
1734 * 6. If partial copy, release iclog; otherwise, continue
1735 * copying more regions into current iclog
1736 * 4. Mark want sync bit (in simulation mode)
1737 * 5. Release iclog for potential flush to on-disk log.
1738 *
1739 * ERRORS:
1740 * 1. Panic if reservation is overrun. This should never happen since
1741 * reservation amounts are generated internal to the filesystem.
1742 * NOTES:
1743 * 1. Tickets are single threaded data structures.
1744 * 2. The XLOG_END_TRANS & XLOG_CONTINUE_TRANS flags are passed down to the
1745 * syncing routine. When a single log_write region needs to span
1746 * multiple in-core logs, the XLOG_CONTINUE_TRANS bit should be set
1747 * on all log operation writes which don't contain the end of the
1748 * region. The XLOG_END_TRANS bit is used for the in-core log
1749 * operation which contains the end of the continued log_write region.
1750 * 3. When xlog_state_get_iclog_space() grabs the rest of the current iclog,
1751 * we don't really know exactly how much space will be used. As a result,
1752 * we don't update ic_offset until the end when we know exactly how many
1753 * bytes have been written out.
1754 */
1755int
1756xlog_write(xfs_mount_t * mp,
1757 xfs_log_iovec_t reg[],
1758 int nentries,
1759 xfs_log_ticket_t tic,
1760 xfs_lsn_t *start_lsn,
1761 xlog_in_core_t **commit_iclog,
1762 uint flags)
1763{
Nathan Scott5493a0f2006-06-28 11:17:28 +10001764 xlog_t *log = mp->m_log;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001765 xlog_ticket_t *ticket = (xlog_ticket_t *)tic;
Nathan Scott5493a0f2006-06-28 11:17:28 +10001766 xlog_in_core_t *iclog = NULL; /* ptr to current in-core log */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001767 xlog_op_header_t *logop_head; /* ptr to log operation header */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001768 __psint_t ptr; /* copy address into data region */
1769 int len; /* # xlog_write() bytes 2 still copy */
1770 int index; /* region index currently copying */
1771 int log_offset; /* offset (from 0) into data region */
1772 int start_rec_copy; /* # bytes to copy for start record */
1773 int partial_copy; /* did we split a region? */
1774 int partial_copy_len;/* # bytes copied if split region */
1775 int need_copy; /* # bytes need to memcpy this region */
1776 int copy_len; /* # bytes actually memcpy'ing */
1777 int copy_off; /* # bytes from entry start */
1778 int contwr; /* continued write of in-core log? */
1779 int error;
1780 int record_cnt = 0, data_cnt = 0;
1781
1782 partial_copy_len = partial_copy = 0;
1783
1784 /* Calculate potential maximum space. Each region gets its own
1785 * xlog_op_header_t and may need to be double word aligned.
1786 */
1787 len = 0;
Tim Shimmin7e9c6392005-09-02 16:42:05 +10001788 if (ticket->t_flags & XLOG_TIC_INITED) { /* acct for start rec of xact */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001789 len += sizeof(xlog_op_header_t);
Christoph Hellwig0adba532007-08-30 17:21:46 +10001790 ticket->t_res_num_ophdrs++;
Tim Shimmin7e9c6392005-09-02 16:42:05 +10001791 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001792
1793 for (index = 0; index < nentries; index++) {
1794 len += sizeof(xlog_op_header_t); /* each region gets >= 1 */
Christoph Hellwig0adba532007-08-30 17:21:46 +10001795 ticket->t_res_num_ophdrs++;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001796 len += reg[index].i_len;
Christoph Hellwig0adba532007-08-30 17:21:46 +10001797 xlog_tic_add_region(ticket, reg[index].i_len, reg[index].i_type);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001798 }
1799 contwr = *start_lsn = 0;
1800
1801 if (ticket->t_curr_res < len) {
Tim Shimmin7e9c6392005-09-02 16:42:05 +10001802 xlog_print_tic_res(mp, ticket);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001803#ifdef DEBUG
1804 xlog_panic(
1805 "xfs_log_write: reservation ran out. Need to up reservation");
1806#else
1807 /* Customer configurable panic */
1808 xfs_cmn_err(XFS_PTAG_LOGRES, CE_ALERT, mp,
1809 "xfs_log_write: reservation ran out. Need to up reservation");
1810 /* If we did not panic, shutdown the filesystem */
Nathan Scott7d04a332006-06-09 14:58:38 +10001811 xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001812#endif
1813 } else
1814 ticket->t_curr_res -= len;
1815
1816 for (index = 0; index < nentries; ) {
1817 if ((error = xlog_state_get_iclog_space(log, len, &iclog, ticket,
1818 &contwr, &log_offset)))
Jesper Juhl014c2542006-01-15 02:37:08 +01001819 return error;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001820
1821 ASSERT(log_offset <= iclog->ic_size - 1);
1822 ptr = (__psint_t) ((char *)iclog->ic_datap+log_offset);
1823
1824 /* start_lsn is the first lsn written to. That's all we need. */
1825 if (! *start_lsn)
1826 *start_lsn = INT_GET(iclog->ic_header.h_lsn, ARCH_CONVERT);
1827
1828 /* This loop writes out as many regions as can fit in the amount
1829 * of space which was allocated by xlog_state_get_iclog_space().
1830 */
1831 while (index < nentries) {
1832 ASSERT(reg[index].i_len % sizeof(__int32_t) == 0);
1833 ASSERT((__psint_t)ptr % sizeof(__int32_t) == 0);
1834 start_rec_copy = 0;
1835
1836 /* If first write for transaction, insert start record.
1837 * We can't be trying to commit if we are inited. We can't
1838 * have any "partial_copy" if we are inited.
1839 */
1840 if (ticket->t_flags & XLOG_TIC_INITED) {
1841 logop_head = (xlog_op_header_t *)ptr;
1842 INT_SET(logop_head->oh_tid, ARCH_CONVERT, ticket->t_tid);
1843 logop_head->oh_clientid = ticket->t_clientid;
1844 logop_head->oh_len = 0;
1845 logop_head->oh_flags = XLOG_START_TRANS;
1846 logop_head->oh_res2 = 0;
1847 ticket->t_flags &= ~XLOG_TIC_INITED; /* clear bit */
1848 record_cnt++;
1849
1850 start_rec_copy = sizeof(xlog_op_header_t);
1851 xlog_write_adv_cnt(ptr, len, log_offset, start_rec_copy);
1852 }
1853
1854 /* Copy log operation header directly into data section */
1855 logop_head = (xlog_op_header_t *)ptr;
1856 INT_SET(logop_head->oh_tid, ARCH_CONVERT, ticket->t_tid);
1857 logop_head->oh_clientid = ticket->t_clientid;
1858 logop_head->oh_res2 = 0;
1859
1860 /* header copied directly */
1861 xlog_write_adv_cnt(ptr, len, log_offset, sizeof(xlog_op_header_t));
1862
1863 /* are we copying a commit or unmount record? */
1864 logop_head->oh_flags = flags;
1865
1866 /*
1867 * We've seen logs corrupted with bad transaction client
1868 * ids. This makes sure that XFS doesn't generate them on.
1869 * Turn this into an EIO and shut down the filesystem.
1870 */
1871 switch (logop_head->oh_clientid) {
1872 case XFS_TRANSACTION:
1873 case XFS_VOLUME:
1874 case XFS_LOG:
1875 break;
1876 default:
1877 xfs_fs_cmn_err(CE_WARN, mp,
1878 "Bad XFS transaction clientid 0x%x in ticket 0x%p",
1879 logop_head->oh_clientid, tic);
1880 return XFS_ERROR(EIO);
1881 }
1882
1883 /* Partial write last time? => (partial_copy != 0)
1884 * need_copy is the amount we'd like to copy if everything could
1885 * fit in the current memcpy.
1886 */
1887 need_copy = reg[index].i_len - partial_copy_len;
1888
1889 copy_off = partial_copy_len;
1890 if (need_copy <= iclog->ic_size - log_offset) { /*complete write */
1891 INT_SET(logop_head->oh_len, ARCH_CONVERT, copy_len = need_copy);
1892 if (partial_copy)
1893 logop_head->oh_flags|= (XLOG_END_TRANS|XLOG_WAS_CONT_TRANS);
1894 partial_copy_len = partial_copy = 0;
1895 } else { /* partial write */
1896 copy_len = iclog->ic_size - log_offset;
1897 INT_SET(logop_head->oh_len, ARCH_CONVERT, copy_len);
1898 logop_head->oh_flags |= XLOG_CONTINUE_TRANS;
1899 if (partial_copy)
1900 logop_head->oh_flags |= XLOG_WAS_CONT_TRANS;
1901 partial_copy_len += copy_len;
1902 partial_copy++;
1903 len += sizeof(xlog_op_header_t); /* from splitting of region */
1904 /* account for new log op header */
1905 ticket->t_curr_res -= sizeof(xlog_op_header_t);
Christoph Hellwig0adba532007-08-30 17:21:46 +10001906 ticket->t_res_num_ophdrs++;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001907 }
1908 xlog_verify_dest_ptr(log, ptr);
1909
1910 /* copy region */
1911 ASSERT(copy_len >= 0);
1912 memcpy((xfs_caddr_t)ptr, reg[index].i_addr + copy_off, copy_len);
1913 xlog_write_adv_cnt(ptr, len, log_offset, copy_len);
1914
1915 /* make copy_len total bytes copied, including headers */
1916 copy_len += start_rec_copy + sizeof(xlog_op_header_t);
1917 record_cnt++;
1918 data_cnt += contwr ? copy_len : 0;
1919 if (partial_copy) { /* copied partial region */
1920 /* already marked WANT_SYNC by xlog_state_get_iclog_space */
1921 xlog_state_finish_copy(log, iclog, record_cnt, data_cnt);
1922 record_cnt = data_cnt = 0;
1923 if ((error = xlog_state_release_iclog(log, iclog)))
Jesper Juhl014c2542006-01-15 02:37:08 +01001924 return error;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001925 break; /* don't increment index */
1926 } else { /* copied entire region */
1927 index++;
1928 partial_copy_len = partial_copy = 0;
1929
1930 if (iclog->ic_size - log_offset <= sizeof(xlog_op_header_t)) {
1931 xlog_state_finish_copy(log, iclog, record_cnt, data_cnt);
1932 record_cnt = data_cnt = 0;
1933 xlog_state_want_sync(log, iclog);
1934 if (commit_iclog) {
1935 ASSERT(flags & XLOG_COMMIT_TRANS);
1936 *commit_iclog = iclog;
1937 } else if ((error = xlog_state_release_iclog(log, iclog)))
Jesper Juhl014c2542006-01-15 02:37:08 +01001938 return error;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001939 if (index == nentries)
1940 return 0; /* we are done */
1941 else
1942 break;
1943 }
1944 } /* if (partial_copy) */
1945 } /* while (index < nentries) */
1946 } /* for (index = 0; index < nentries; ) */
1947 ASSERT(len == 0);
1948
1949 xlog_state_finish_copy(log, iclog, record_cnt, data_cnt);
1950 if (commit_iclog) {
1951 ASSERT(flags & XLOG_COMMIT_TRANS);
1952 *commit_iclog = iclog;
1953 return 0;
1954 }
Jesper Juhl014c2542006-01-15 02:37:08 +01001955 return xlog_state_release_iclog(log, iclog);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001956} /* xlog_write */
1957
1958
1959/*****************************************************************************
1960 *
1961 * State Machine functions
1962 *
1963 *****************************************************************************
1964 */
1965
1966/* Clean iclogs starting from the head. This ordering must be
1967 * maintained, so an iclog doesn't become ACTIVE beyond one that
1968 * is SYNCING. This is also required to maintain the notion that we use
1969 * a counting semaphore to hold off would be writers to the log when every
1970 * iclog is trying to sync to disk.
1971 *
1972 * State Change: DIRTY -> ACTIVE
1973 */
Christoph Hellwigba0f32d2005-06-21 15:36:52 +10001974STATIC void
Linus Torvalds1da177e2005-04-16 15:20:36 -07001975xlog_state_clean_log(xlog_t *log)
1976{
1977 xlog_in_core_t *iclog;
1978 int changed = 0;
1979
1980 iclog = log->l_iclog;
1981 do {
1982 if (iclog->ic_state == XLOG_STATE_DIRTY) {
1983 iclog->ic_state = XLOG_STATE_ACTIVE;
1984 iclog->ic_offset = 0;
1985 iclog->ic_callback = NULL; /* don't need to free */
1986 /*
1987 * If the number of ops in this iclog indicate it just
1988 * contains the dummy transaction, we can
1989 * change state into IDLE (the second time around).
1990 * Otherwise we should change the state into
1991 * NEED a dummy.
1992 * We don't need to cover the dummy.
1993 */
1994 if (!changed &&
1995 (INT_GET(iclog->ic_header.h_num_logops, ARCH_CONVERT) == XLOG_COVER_OPS)) {
1996 changed = 1;
1997 } else {
1998 /*
1999 * We have two dirty iclogs so start over
2000 * This could also be num of ops indicates
2001 * this is not the dummy going out.
2002 */
2003 changed = 2;
2004 }
2005 iclog->ic_header.h_num_logops = 0;
2006 memset(iclog->ic_header.h_cycle_data, 0,
2007 sizeof(iclog->ic_header.h_cycle_data));
2008 iclog->ic_header.h_lsn = 0;
2009 } else if (iclog->ic_state == XLOG_STATE_ACTIVE)
2010 /* do nothing */;
2011 else
2012 break; /* stop cleaning */
2013 iclog = iclog->ic_next;
2014 } while (iclog != log->l_iclog);
2015
2016 /* log is locked when we are called */
2017 /*
2018 * Change state for the dummy log recording.
2019 * We usually go to NEED. But we go to NEED2 if the changed indicates
2020 * we are done writing the dummy record.
2021 * If we are done with the second dummy recored (DONE2), then
2022 * we go to IDLE.
2023 */
2024 if (changed) {
2025 switch (log->l_covered_state) {
2026 case XLOG_STATE_COVER_IDLE:
2027 case XLOG_STATE_COVER_NEED:
2028 case XLOG_STATE_COVER_NEED2:
2029 log->l_covered_state = XLOG_STATE_COVER_NEED;
2030 break;
2031
2032 case XLOG_STATE_COVER_DONE:
2033 if (changed == 1)
2034 log->l_covered_state = XLOG_STATE_COVER_NEED2;
2035 else
2036 log->l_covered_state = XLOG_STATE_COVER_NEED;
2037 break;
2038
2039 case XLOG_STATE_COVER_DONE2:
2040 if (changed == 1)
2041 log->l_covered_state = XLOG_STATE_COVER_IDLE;
2042 else
2043 log->l_covered_state = XLOG_STATE_COVER_NEED;
2044 break;
2045
2046 default:
2047 ASSERT(0);
2048 }
2049 }
2050} /* xlog_state_clean_log */
2051
2052STATIC xfs_lsn_t
2053xlog_get_lowest_lsn(
2054 xlog_t *log)
2055{
2056 xlog_in_core_t *lsn_log;
2057 xfs_lsn_t lowest_lsn, lsn;
2058
2059 lsn_log = log->l_iclog;
2060 lowest_lsn = 0;
2061 do {
2062 if (!(lsn_log->ic_state & (XLOG_STATE_ACTIVE|XLOG_STATE_DIRTY))) {
2063 lsn = INT_GET(lsn_log->ic_header.h_lsn, ARCH_CONVERT);
2064 if ((lsn && !lowest_lsn) ||
2065 (XFS_LSN_CMP(lsn, lowest_lsn) < 0)) {
2066 lowest_lsn = lsn;
2067 }
2068 }
2069 lsn_log = lsn_log->ic_next;
2070 } while (lsn_log != log->l_iclog);
Jesper Juhl014c2542006-01-15 02:37:08 +01002071 return lowest_lsn;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002072}
2073
2074
2075STATIC void
2076xlog_state_do_callback(
2077 xlog_t *log,
2078 int aborted,
2079 xlog_in_core_t *ciclog)
2080{
2081 xlog_in_core_t *iclog;
2082 xlog_in_core_t *first_iclog; /* used to know when we've
2083 * processed all iclogs once */
2084 xfs_log_callback_t *cb, *cb_next;
2085 int flushcnt = 0;
2086 xfs_lsn_t lowest_lsn;
2087 int ioerrors; /* counter: iclogs with errors */
2088 int loopdidcallbacks; /* flag: inner loop did callbacks*/
2089 int funcdidcallbacks; /* flag: function did callbacks */
2090 int repeats; /* for issuing console warnings if
2091 * looping too many times */
2092 SPLDECL(s);
2093
2094 s = LOG_LOCK(log);
2095 first_iclog = iclog = log->l_iclog;
2096 ioerrors = 0;
2097 funcdidcallbacks = 0;
2098 repeats = 0;
2099
2100 do {
2101 /*
2102 * Scan all iclogs starting with the one pointed to by the
2103 * log. Reset this starting point each time the log is
2104 * unlocked (during callbacks).
2105 *
2106 * Keep looping through iclogs until one full pass is made
2107 * without running any callbacks.
2108 */
2109 first_iclog = log->l_iclog;
2110 iclog = log->l_iclog;
2111 loopdidcallbacks = 0;
2112 repeats++;
2113
2114 do {
2115
2116 /* skip all iclogs in the ACTIVE & DIRTY states */
2117 if (iclog->ic_state &
2118 (XLOG_STATE_ACTIVE|XLOG_STATE_DIRTY)) {
2119 iclog = iclog->ic_next;
2120 continue;
2121 }
2122
2123 /*
2124 * Between marking a filesystem SHUTDOWN and stopping
2125 * the log, we do flush all iclogs to disk (if there
2126 * wasn't a log I/O error). So, we do want things to
2127 * go smoothly in case of just a SHUTDOWN w/o a
2128 * LOG_IO_ERROR.
2129 */
2130 if (!(iclog->ic_state & XLOG_STATE_IOERROR)) {
2131 /*
2132 * Can only perform callbacks in order. Since
2133 * this iclog is not in the DONE_SYNC/
2134 * DO_CALLBACK state, we skip the rest and
2135 * just try to clean up. If we set our iclog
2136 * to DO_CALLBACK, we will not process it when
2137 * we retry since a previous iclog is in the
2138 * CALLBACK and the state cannot change since
2139 * we are holding the LOG_LOCK.
2140 */
2141 if (!(iclog->ic_state &
2142 (XLOG_STATE_DONE_SYNC |
2143 XLOG_STATE_DO_CALLBACK))) {
2144 if (ciclog && (ciclog->ic_state ==
2145 XLOG_STATE_DONE_SYNC)) {
2146 ciclog->ic_state = XLOG_STATE_DO_CALLBACK;
2147 }
2148 break;
2149 }
2150 /*
2151 * We now have an iclog that is in either the
2152 * DO_CALLBACK or DONE_SYNC states. The other
2153 * states (WANT_SYNC, SYNCING, or CALLBACK were
2154 * caught by the above if and are going to
2155 * clean (i.e. we aren't doing their callbacks)
2156 * see the above if.
2157 */
2158
2159 /*
2160 * We will do one more check here to see if we
2161 * have chased our tail around.
2162 */
2163
2164 lowest_lsn = xlog_get_lowest_lsn(log);
2165 if (lowest_lsn && (
2166 XFS_LSN_CMP(
2167 lowest_lsn,
2168 INT_GET(iclog->ic_header.h_lsn, ARCH_CONVERT)
2169 )<0)) {
2170 iclog = iclog->ic_next;
2171 continue; /* Leave this iclog for
2172 * another thread */
2173 }
2174
2175 iclog->ic_state = XLOG_STATE_CALLBACK;
2176
2177 LOG_UNLOCK(log, s);
2178
2179 /* l_last_sync_lsn field protected by
2180 * GRANT_LOCK. Don't worry about iclog's lsn.
2181 * No one else can be here except us.
2182 */
2183 s = GRANT_LOCK(log);
2184 ASSERT(XFS_LSN_CMP(
2185 log->l_last_sync_lsn,
2186 INT_GET(iclog->ic_header.h_lsn, ARCH_CONVERT)
2187 )<=0);
2188 log->l_last_sync_lsn = INT_GET(iclog->ic_header.h_lsn, ARCH_CONVERT);
2189 GRANT_UNLOCK(log, s);
2190
2191 /*
2192 * Keep processing entries in the callback list
2193 * until we come around and it is empty. We
2194 * need to atomically see that the list is
2195 * empty and change the state to DIRTY so that
2196 * we don't miss any more callbacks being added.
2197 */
2198 s = LOG_LOCK(log);
2199 } else {
2200 ioerrors++;
2201 }
2202 cb = iclog->ic_callback;
2203
Christoph Hellwig4b809162007-08-16 15:37:36 +10002204 while (cb) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002205 iclog->ic_callback_tail = &(iclog->ic_callback);
2206 iclog->ic_callback = NULL;
2207 LOG_UNLOCK(log, s);
2208
2209 /* perform callbacks in the order given */
Christoph Hellwig4b809162007-08-16 15:37:36 +10002210 for (; cb; cb = cb_next) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002211 cb_next = cb->cb_next;
2212 cb->cb_func(cb->cb_arg, aborted);
2213 }
2214 s = LOG_LOCK(log);
2215 cb = iclog->ic_callback;
2216 }
2217
2218 loopdidcallbacks++;
2219 funcdidcallbacks++;
2220
Christoph Hellwig4b809162007-08-16 15:37:36 +10002221 ASSERT(iclog->ic_callback == NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002222 if (!(iclog->ic_state & XLOG_STATE_IOERROR))
2223 iclog->ic_state = XLOG_STATE_DIRTY;
2224
2225 /*
2226 * Transition from DIRTY to ACTIVE if applicable.
2227 * NOP if STATE_IOERROR.
2228 */
2229 xlog_state_clean_log(log);
2230
2231 /* wake up threads waiting in xfs_log_force() */
2232 sv_broadcast(&iclog->ic_forcesema);
2233
2234 iclog = iclog->ic_next;
2235 } while (first_iclog != iclog);
Nathan Scotta3c66852006-09-28 11:02:14 +10002236
2237 if (repeats > 5000) {
2238 flushcnt += repeats;
2239 repeats = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002240 xfs_fs_cmn_err(CE_WARN, log->l_mp,
Nathan Scotta3c66852006-09-28 11:02:14 +10002241 "%s: possible infinite loop (%d iterations)",
2242 __FUNCTION__, flushcnt);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002243 }
2244 } while (!ioerrors && loopdidcallbacks);
2245
2246 /*
2247 * make one last gasp attempt to see if iclogs are being left in
2248 * limbo..
2249 */
2250#ifdef DEBUG
2251 if (funcdidcallbacks) {
2252 first_iclog = iclog = log->l_iclog;
2253 do {
2254 ASSERT(iclog->ic_state != XLOG_STATE_DO_CALLBACK);
2255 /*
2256 * Terminate the loop if iclogs are found in states
2257 * which will cause other threads to clean up iclogs.
2258 *
2259 * SYNCING - i/o completion will go through logs
2260 * DONE_SYNC - interrupt thread should be waiting for
2261 * LOG_LOCK
2262 * IOERROR - give up hope all ye who enter here
2263 */
2264 if (iclog->ic_state == XLOG_STATE_WANT_SYNC ||
2265 iclog->ic_state == XLOG_STATE_SYNCING ||
2266 iclog->ic_state == XLOG_STATE_DONE_SYNC ||
2267 iclog->ic_state == XLOG_STATE_IOERROR )
2268 break;
2269 iclog = iclog->ic_next;
2270 } while (first_iclog != iclog);
2271 }
2272#endif
2273
Nathan Scotta3c66852006-09-28 11:02:14 +10002274 flushcnt = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002275 if (log->l_iclog->ic_state & (XLOG_STATE_ACTIVE|XLOG_STATE_IOERROR)) {
2276 flushcnt = log->l_flushcnt;
2277 log->l_flushcnt = 0;
2278 }
2279 LOG_UNLOCK(log, s);
2280 while (flushcnt--)
2281 vsema(&log->l_flushsema);
2282} /* xlog_state_do_callback */
2283
2284
2285/*
2286 * Finish transitioning this iclog to the dirty state.
2287 *
2288 * Make sure that we completely execute this routine only when this is
2289 * the last call to the iclog. There is a good chance that iclog flushes,
2290 * when we reach the end of the physical log, get turned into 2 separate
2291 * calls to bwrite. Hence, one iclog flush could generate two calls to this
2292 * routine. By using the reference count bwritecnt, we guarantee that only
2293 * the second completion goes through.
2294 *
2295 * Callbacks could take time, so they are done outside the scope of the
2296 * global state machine log lock. Assume that the calls to cvsema won't
2297 * take a long time. At least we know it won't sleep.
2298 */
2299void
2300xlog_state_done_syncing(
2301 xlog_in_core_t *iclog,
2302 int aborted)
2303{
2304 xlog_t *log = iclog->ic_log;
2305 SPLDECL(s);
2306
2307 s = LOG_LOCK(log);
2308
2309 ASSERT(iclog->ic_state == XLOG_STATE_SYNCING ||
2310 iclog->ic_state == XLOG_STATE_IOERROR);
2311 ASSERT(iclog->ic_refcnt == 0);
2312 ASSERT(iclog->ic_bwritecnt == 1 || iclog->ic_bwritecnt == 2);
2313
2314
2315 /*
2316 * If we got an error, either on the first buffer, or in the case of
2317 * split log writes, on the second, we mark ALL iclogs STATE_IOERROR,
2318 * and none should ever be attempted to be written to disk
2319 * again.
2320 */
2321 if (iclog->ic_state != XLOG_STATE_IOERROR) {
2322 if (--iclog->ic_bwritecnt == 1) {
2323 LOG_UNLOCK(log, s);
2324 return;
2325 }
2326 iclog->ic_state = XLOG_STATE_DONE_SYNC;
2327 }
2328
2329 /*
2330 * Someone could be sleeping prior to writing out the next
2331 * iclog buffer, we wake them all, one will get to do the
2332 * I/O, the others get to wait for the result.
2333 */
2334 sv_broadcast(&iclog->ic_writesema);
2335 LOG_UNLOCK(log, s);
2336 xlog_state_do_callback(log, aborted, iclog); /* also cleans log */
2337} /* xlog_state_done_syncing */
2338
2339
2340/*
2341 * If the head of the in-core log ring is not (ACTIVE or DIRTY), then we must
2342 * sleep. The flush semaphore is set to the number of in-core buffers and
2343 * decremented around disk syncing. Therefore, if all buffers are syncing,
2344 * this semaphore will cause new writes to sleep until a sync completes.
2345 * Otherwise, this code just does p() followed by v(). This approximates
2346 * a sleep/wakeup except we can't race.
2347 *
2348 * The in-core logs are used in a circular fashion. They are not used
2349 * out-of-order even when an iclog past the head is free.
2350 *
2351 * return:
2352 * * log_offset where xlog_write() can start writing into the in-core
2353 * log's data space.
2354 * * in-core log pointer to which xlog_write() should write.
2355 * * boolean indicating this is a continued write to an in-core log.
2356 * If this is the last write, then the in-core log's offset field
2357 * needs to be incremented, depending on the amount of data which
2358 * is copied.
2359 */
2360int
2361xlog_state_get_iclog_space(xlog_t *log,
2362 int len,
2363 xlog_in_core_t **iclogp,
2364 xlog_ticket_t *ticket,
2365 int *continued_write,
2366 int *logoffsetp)
2367{
2368 SPLDECL(s);
2369 int log_offset;
2370 xlog_rec_header_t *head;
2371 xlog_in_core_t *iclog;
2372 int error;
2373
2374restart:
2375 s = LOG_LOCK(log);
2376 if (XLOG_FORCED_SHUTDOWN(log)) {
2377 LOG_UNLOCK(log, s);
2378 return XFS_ERROR(EIO);
2379 }
2380
2381 iclog = log->l_iclog;
2382 if (! (iclog->ic_state == XLOG_STATE_ACTIVE)) {
2383 log->l_flushcnt++;
2384 LOG_UNLOCK(log, s);
2385 xlog_trace_iclog(iclog, XLOG_TRACE_SLEEP_FLUSH);
2386 XFS_STATS_INC(xs_log_noiclogs);
2387 /* Ensure that log writes happen */
2388 psema(&log->l_flushsema, PINOD);
2389 goto restart;
2390 }
2391 ASSERT(iclog->ic_state == XLOG_STATE_ACTIVE);
2392 head = &iclog->ic_header;
2393
2394 iclog->ic_refcnt++; /* prevents sync */
2395 log_offset = iclog->ic_offset;
2396
2397 /* On the 1st write to an iclog, figure out lsn. This works
2398 * if iclogs marked XLOG_STATE_WANT_SYNC always write out what they are
2399 * committing to. If the offset is set, that's how many blocks
2400 * must be written.
2401 */
2402 if (log_offset == 0) {
2403 ticket->t_curr_res -= log->l_iclog_hsize;
Christoph Hellwig0adba532007-08-30 17:21:46 +10002404 xlog_tic_add_region(ticket,
Tim Shimmin7e9c6392005-09-02 16:42:05 +10002405 log->l_iclog_hsize,
2406 XLOG_REG_TYPE_LRHEADER);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002407 INT_SET(head->h_cycle, ARCH_CONVERT, log->l_curr_cycle);
2408 ASSIGN_LSN(head->h_lsn, log);
2409 ASSERT(log->l_curr_block >= 0);
2410 }
2411
2412 /* If there is enough room to write everything, then do it. Otherwise,
2413 * claim the rest of the region and make sure the XLOG_STATE_WANT_SYNC
2414 * bit is on, so this will get flushed out. Don't update ic_offset
2415 * until you know exactly how many bytes get copied. Therefore, wait
2416 * until later to update ic_offset.
2417 *
2418 * xlog_write() algorithm assumes that at least 2 xlog_op_header_t's
2419 * can fit into remaining data section.
2420 */
2421 if (iclog->ic_size - iclog->ic_offset < 2*sizeof(xlog_op_header_t)) {
2422 xlog_state_switch_iclogs(log, iclog, iclog->ic_size);
2423
2424 /* If I'm the only one writing to this iclog, sync it to disk */
2425 if (iclog->ic_refcnt == 1) {
2426 LOG_UNLOCK(log, s);
2427 if ((error = xlog_state_release_iclog(log, iclog)))
Jesper Juhl014c2542006-01-15 02:37:08 +01002428 return error;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002429 } else {
2430 iclog->ic_refcnt--;
2431 LOG_UNLOCK(log, s);
2432 }
2433 goto restart;
2434 }
2435
2436 /* Do we have enough room to write the full amount in the remainder
2437 * of this iclog? Or must we continue a write on the next iclog and
2438 * mark this iclog as completely taken? In the case where we switch
2439 * iclogs (to mark it taken), this particular iclog will release/sync
2440 * to disk in xlog_write().
2441 */
2442 if (len <= iclog->ic_size - iclog->ic_offset) {
2443 *continued_write = 0;
2444 iclog->ic_offset += len;
2445 } else {
2446 *continued_write = 1;
2447 xlog_state_switch_iclogs(log, iclog, iclog->ic_size);
2448 }
2449 *iclogp = iclog;
2450
2451 ASSERT(iclog->ic_offset <= iclog->ic_size);
2452 LOG_UNLOCK(log, s);
2453
2454 *logoffsetp = log_offset;
2455 return 0;
2456} /* xlog_state_get_iclog_space */
2457
2458/*
2459 * Atomically get the log space required for a log ticket.
2460 *
2461 * Once a ticket gets put onto the reserveq, it will only return after
2462 * the needed reservation is satisfied.
2463 */
2464STATIC int
2465xlog_grant_log_space(xlog_t *log,
2466 xlog_ticket_t *tic)
2467{
2468 int free_bytes;
2469 int need_bytes;
2470 SPLDECL(s);
2471#ifdef DEBUG
2472 xfs_lsn_t tail_lsn;
2473#endif
2474
2475
2476#ifdef DEBUG
2477 if (log->l_flags & XLOG_ACTIVE_RECOVERY)
2478 panic("grant Recovery problem");
2479#endif
2480
2481 /* Is there space or do we need to sleep? */
2482 s = GRANT_LOCK(log);
2483 xlog_trace_loggrant(log, tic, "xlog_grant_log_space: enter");
2484
2485 /* something is already sleeping; insert new transaction at end */
2486 if (log->l_reserve_headq) {
Christoph Hellwigdd954c62006-01-11 15:34:50 +11002487 xlog_ins_ticketq(&log->l_reserve_headq, tic);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002488 xlog_trace_loggrant(log, tic,
2489 "xlog_grant_log_space: sleep 1");
2490 /*
2491 * Gotta check this before going to sleep, while we're
2492 * holding the grant lock.
2493 */
2494 if (XLOG_FORCED_SHUTDOWN(log))
2495 goto error_return;
2496
2497 XFS_STATS_INC(xs_sleep_logspace);
2498 sv_wait(&tic->t_sema, PINOD|PLTWAIT, &log->l_grant_lock, s);
2499 /*
2500 * If we got an error, and the filesystem is shutting down,
2501 * we'll catch it down below. So just continue...
2502 */
2503 xlog_trace_loggrant(log, tic,
2504 "xlog_grant_log_space: wake 1");
2505 s = GRANT_LOCK(log);
2506 }
2507 if (tic->t_flags & XFS_LOG_PERM_RESERV)
2508 need_bytes = tic->t_unit_res*tic->t_ocnt;
2509 else
2510 need_bytes = tic->t_unit_res;
2511
2512redo:
2513 if (XLOG_FORCED_SHUTDOWN(log))
2514 goto error_return;
2515
2516 free_bytes = xlog_space_left(log, log->l_grant_reserve_cycle,
2517 log->l_grant_reserve_bytes);
2518 if (free_bytes < need_bytes) {
2519 if ((tic->t_flags & XLOG_TIC_IN_Q) == 0)
Christoph Hellwigdd954c62006-01-11 15:34:50 +11002520 xlog_ins_ticketq(&log->l_reserve_headq, tic);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002521 xlog_trace_loggrant(log, tic,
2522 "xlog_grant_log_space: sleep 2");
2523 XFS_STATS_INC(xs_sleep_logspace);
2524 sv_wait(&tic->t_sema, PINOD|PLTWAIT, &log->l_grant_lock, s);
2525
2526 if (XLOG_FORCED_SHUTDOWN(log)) {
2527 s = GRANT_LOCK(log);
2528 goto error_return;
2529 }
2530
2531 xlog_trace_loggrant(log, tic,
2532 "xlog_grant_log_space: wake 2");
2533 xlog_grant_push_ail(log->l_mp, need_bytes);
2534 s = GRANT_LOCK(log);
2535 goto redo;
2536 } else if (tic->t_flags & XLOG_TIC_IN_Q)
Christoph Hellwigdd954c62006-01-11 15:34:50 +11002537 xlog_del_ticketq(&log->l_reserve_headq, tic);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002538
2539 /* we've got enough space */
Christoph Hellwigdd954c62006-01-11 15:34:50 +11002540 xlog_grant_add_space(log, need_bytes);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002541#ifdef DEBUG
2542 tail_lsn = log->l_tail_lsn;
2543 /*
2544 * Check to make sure the grant write head didn't just over lap the
2545 * tail. If the cycles are the same, we can't be overlapping.
2546 * Otherwise, make sure that the cycles differ by exactly one and
2547 * check the byte count.
2548 */
2549 if (CYCLE_LSN(tail_lsn) != log->l_grant_write_cycle) {
2550 ASSERT(log->l_grant_write_cycle-1 == CYCLE_LSN(tail_lsn));
2551 ASSERT(log->l_grant_write_bytes <= BBTOB(BLOCK_LSN(tail_lsn)));
2552 }
2553#endif
2554 xlog_trace_loggrant(log, tic, "xlog_grant_log_space: exit");
2555 xlog_verify_grant_head(log, 1);
2556 GRANT_UNLOCK(log, s);
2557 return 0;
2558
2559 error_return:
2560 if (tic->t_flags & XLOG_TIC_IN_Q)
Christoph Hellwigdd954c62006-01-11 15:34:50 +11002561 xlog_del_ticketq(&log->l_reserve_headq, tic);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002562 xlog_trace_loggrant(log, tic, "xlog_grant_log_space: err_ret");
2563 /*
2564 * If we are failing, make sure the ticket doesn't have any
2565 * current reservations. We don't want to add this back when
2566 * the ticket/transaction gets cancelled.
2567 */
2568 tic->t_curr_res = 0;
2569 tic->t_cnt = 0; /* ungrant will give back unit_res * t_cnt. */
2570 GRANT_UNLOCK(log, s);
2571 return XFS_ERROR(EIO);
2572} /* xlog_grant_log_space */
2573
2574
2575/*
2576 * Replenish the byte reservation required by moving the grant write head.
2577 *
2578 *
2579 */
2580STATIC int
2581xlog_regrant_write_log_space(xlog_t *log,
2582 xlog_ticket_t *tic)
2583{
2584 SPLDECL(s);
2585 int free_bytes, need_bytes;
2586 xlog_ticket_t *ntic;
2587#ifdef DEBUG
2588 xfs_lsn_t tail_lsn;
2589#endif
2590
2591 tic->t_curr_res = tic->t_unit_res;
Christoph Hellwig0adba532007-08-30 17:21:46 +10002592 xlog_tic_reset_res(tic);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002593
2594 if (tic->t_cnt > 0)
Jesper Juhl014c2542006-01-15 02:37:08 +01002595 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002596
2597#ifdef DEBUG
2598 if (log->l_flags & XLOG_ACTIVE_RECOVERY)
2599 panic("regrant Recovery problem");
2600#endif
2601
2602 s = GRANT_LOCK(log);
2603 xlog_trace_loggrant(log, tic, "xlog_regrant_write_log_space: enter");
2604
2605 if (XLOG_FORCED_SHUTDOWN(log))
2606 goto error_return;
2607
2608 /* If there are other waiters on the queue then give them a
2609 * chance at logspace before us. Wake up the first waiters,
2610 * if we do not wake up all the waiters then go to sleep waiting
2611 * for more free space, otherwise try to get some space for
2612 * this transaction.
2613 */
2614
2615 if ((ntic = log->l_write_headq)) {
2616 free_bytes = xlog_space_left(log, log->l_grant_write_cycle,
2617 log->l_grant_write_bytes);
2618 do {
2619 ASSERT(ntic->t_flags & XLOG_TIC_PERM_RESERV);
2620
2621 if (free_bytes < ntic->t_unit_res)
2622 break;
2623 free_bytes -= ntic->t_unit_res;
2624 sv_signal(&ntic->t_sema);
2625 ntic = ntic->t_next;
2626 } while (ntic != log->l_write_headq);
2627
2628 if (ntic != log->l_write_headq) {
2629 if ((tic->t_flags & XLOG_TIC_IN_Q) == 0)
Christoph Hellwigdd954c62006-01-11 15:34:50 +11002630 xlog_ins_ticketq(&log->l_write_headq, tic);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002631
2632 xlog_trace_loggrant(log, tic,
2633 "xlog_regrant_write_log_space: sleep 1");
2634 XFS_STATS_INC(xs_sleep_logspace);
2635 sv_wait(&tic->t_sema, PINOD|PLTWAIT,
2636 &log->l_grant_lock, s);
2637
2638 /* If we're shutting down, this tic is already
2639 * off the queue */
2640 if (XLOG_FORCED_SHUTDOWN(log)) {
2641 s = GRANT_LOCK(log);
2642 goto error_return;
2643 }
2644
2645 xlog_trace_loggrant(log, tic,
2646 "xlog_regrant_write_log_space: wake 1");
2647 xlog_grant_push_ail(log->l_mp, tic->t_unit_res);
2648 s = GRANT_LOCK(log);
2649 }
2650 }
2651
2652 need_bytes = tic->t_unit_res;
2653
2654redo:
2655 if (XLOG_FORCED_SHUTDOWN(log))
2656 goto error_return;
2657
2658 free_bytes = xlog_space_left(log, log->l_grant_write_cycle,
2659 log->l_grant_write_bytes);
2660 if (free_bytes < need_bytes) {
2661 if ((tic->t_flags & XLOG_TIC_IN_Q) == 0)
Christoph Hellwigdd954c62006-01-11 15:34:50 +11002662 xlog_ins_ticketq(&log->l_write_headq, tic);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002663 XFS_STATS_INC(xs_sleep_logspace);
2664 sv_wait(&tic->t_sema, PINOD|PLTWAIT, &log->l_grant_lock, s);
2665
2666 /* If we're shutting down, this tic is already off the queue */
2667 if (XLOG_FORCED_SHUTDOWN(log)) {
2668 s = GRANT_LOCK(log);
2669 goto error_return;
2670 }
2671
2672 xlog_trace_loggrant(log, tic,
2673 "xlog_regrant_write_log_space: wake 2");
2674 xlog_grant_push_ail(log->l_mp, need_bytes);
2675 s = GRANT_LOCK(log);
2676 goto redo;
2677 } else if (tic->t_flags & XLOG_TIC_IN_Q)
Christoph Hellwigdd954c62006-01-11 15:34:50 +11002678 xlog_del_ticketq(&log->l_write_headq, tic);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002679
Christoph Hellwigdd954c62006-01-11 15:34:50 +11002680 /* we've got enough space */
2681 xlog_grant_add_space_write(log, need_bytes);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002682#ifdef DEBUG
2683 tail_lsn = log->l_tail_lsn;
2684 if (CYCLE_LSN(tail_lsn) != log->l_grant_write_cycle) {
2685 ASSERT(log->l_grant_write_cycle-1 == CYCLE_LSN(tail_lsn));
2686 ASSERT(log->l_grant_write_bytes <= BBTOB(BLOCK_LSN(tail_lsn)));
2687 }
2688#endif
2689
2690 xlog_trace_loggrant(log, tic, "xlog_regrant_write_log_space: exit");
2691 xlog_verify_grant_head(log, 1);
2692 GRANT_UNLOCK(log, s);
Jesper Juhl014c2542006-01-15 02:37:08 +01002693 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002694
2695
2696 error_return:
2697 if (tic->t_flags & XLOG_TIC_IN_Q)
Christoph Hellwigdd954c62006-01-11 15:34:50 +11002698 xlog_del_ticketq(&log->l_reserve_headq, tic);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002699 xlog_trace_loggrant(log, tic, "xlog_regrant_write_log_space: err_ret");
2700 /*
2701 * If we are failing, make sure the ticket doesn't have any
2702 * current reservations. We don't want to add this back when
2703 * the ticket/transaction gets cancelled.
2704 */
2705 tic->t_curr_res = 0;
2706 tic->t_cnt = 0; /* ungrant will give back unit_res * t_cnt. */
2707 GRANT_UNLOCK(log, s);
2708 return XFS_ERROR(EIO);
2709} /* xlog_regrant_write_log_space */
2710
2711
2712/* The first cnt-1 times through here we don't need to
2713 * move the grant write head because the permanent
2714 * reservation has reserved cnt times the unit amount.
2715 * Release part of current permanent unit reservation and
2716 * reset current reservation to be one units worth. Also
2717 * move grant reservation head forward.
2718 */
2719STATIC void
2720xlog_regrant_reserve_log_space(xlog_t *log,
2721 xlog_ticket_t *ticket)
2722{
2723 SPLDECL(s);
2724
2725 xlog_trace_loggrant(log, ticket,
2726 "xlog_regrant_reserve_log_space: enter");
2727 if (ticket->t_cnt > 0)
2728 ticket->t_cnt--;
2729
2730 s = GRANT_LOCK(log);
Christoph Hellwigdd954c62006-01-11 15:34:50 +11002731 xlog_grant_sub_space(log, ticket->t_curr_res);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002732 ticket->t_curr_res = ticket->t_unit_res;
Christoph Hellwig0adba532007-08-30 17:21:46 +10002733 xlog_tic_reset_res(ticket);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002734 xlog_trace_loggrant(log, ticket,
2735 "xlog_regrant_reserve_log_space: sub current res");
2736 xlog_verify_grant_head(log, 1);
2737
2738 /* just return if we still have some of the pre-reserved space */
2739 if (ticket->t_cnt > 0) {
2740 GRANT_UNLOCK(log, s);
2741 return;
2742 }
2743
Christoph Hellwigdd954c62006-01-11 15:34:50 +11002744 xlog_grant_add_space_reserve(log, ticket->t_unit_res);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002745 xlog_trace_loggrant(log, ticket,
2746 "xlog_regrant_reserve_log_space: exit");
2747 xlog_verify_grant_head(log, 0);
2748 GRANT_UNLOCK(log, s);
2749 ticket->t_curr_res = ticket->t_unit_res;
Christoph Hellwig0adba532007-08-30 17:21:46 +10002750 xlog_tic_reset_res(ticket);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002751} /* xlog_regrant_reserve_log_space */
2752
2753
2754/*
2755 * Give back the space left from a reservation.
2756 *
2757 * All the information we need to make a correct determination of space left
2758 * is present. For non-permanent reservations, things are quite easy. The
2759 * count should have been decremented to zero. We only need to deal with the
2760 * space remaining in the current reservation part of the ticket. If the
2761 * ticket contains a permanent reservation, there may be left over space which
2762 * needs to be released. A count of N means that N-1 refills of the current
2763 * reservation can be done before we need to ask for more space. The first
2764 * one goes to fill up the first current reservation. Once we run out of
2765 * space, the count will stay at zero and the only space remaining will be
2766 * in the current reservation field.
2767 */
2768STATIC void
2769xlog_ungrant_log_space(xlog_t *log,
2770 xlog_ticket_t *ticket)
2771{
2772 SPLDECL(s);
2773
2774 if (ticket->t_cnt > 0)
2775 ticket->t_cnt--;
2776
2777 s = GRANT_LOCK(log);
2778 xlog_trace_loggrant(log, ticket, "xlog_ungrant_log_space: enter");
2779
Christoph Hellwigdd954c62006-01-11 15:34:50 +11002780 xlog_grant_sub_space(log, ticket->t_curr_res);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002781
2782 xlog_trace_loggrant(log, ticket, "xlog_ungrant_log_space: sub current");
2783
2784 /* If this is a permanent reservation ticket, we may be able to free
2785 * up more space based on the remaining count.
2786 */
2787 if (ticket->t_cnt > 0) {
2788 ASSERT(ticket->t_flags & XLOG_TIC_PERM_RESERV);
Christoph Hellwigdd954c62006-01-11 15:34:50 +11002789 xlog_grant_sub_space(log, ticket->t_unit_res*ticket->t_cnt);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002790 }
2791
2792 xlog_trace_loggrant(log, ticket, "xlog_ungrant_log_space: exit");
2793 xlog_verify_grant_head(log, 1);
2794 GRANT_UNLOCK(log, s);
2795 xfs_log_move_tail(log->l_mp, 1);
2796} /* xlog_ungrant_log_space */
2797
2798
2799/*
2800 * Atomically put back used ticket.
2801 */
2802void
2803xlog_state_put_ticket(xlog_t *log,
2804 xlog_ticket_t *tic)
2805{
2806 unsigned long s;
2807
2808 s = LOG_LOCK(log);
2809 xlog_ticket_put(log, tic);
2810 LOG_UNLOCK(log, s);
2811} /* xlog_state_put_ticket */
2812
2813/*
2814 * Flush iclog to disk if this is the last reference to the given iclog and
2815 * the WANT_SYNC bit is set.
2816 *
2817 * When this function is entered, the iclog is not necessarily in the
2818 * WANT_SYNC state. It may be sitting around waiting to get filled.
2819 *
2820 *
2821 */
2822int
2823xlog_state_release_iclog(xlog_t *log,
2824 xlog_in_core_t *iclog)
2825{
2826 SPLDECL(s);
2827 int sync = 0; /* do we sync? */
2828
2829 xlog_assign_tail_lsn(log->l_mp);
2830
2831 s = LOG_LOCK(log);
2832
2833 if (iclog->ic_state & XLOG_STATE_IOERROR) {
2834 LOG_UNLOCK(log, s);
2835 return XFS_ERROR(EIO);
2836 }
2837
2838 ASSERT(iclog->ic_refcnt > 0);
2839 ASSERT(iclog->ic_state == XLOG_STATE_ACTIVE ||
2840 iclog->ic_state == XLOG_STATE_WANT_SYNC);
2841
2842 if (--iclog->ic_refcnt == 0 &&
2843 iclog->ic_state == XLOG_STATE_WANT_SYNC) {
2844 sync++;
2845 iclog->ic_state = XLOG_STATE_SYNCING;
2846 INT_SET(iclog->ic_header.h_tail_lsn, ARCH_CONVERT, log->l_tail_lsn);
2847 xlog_verify_tail_lsn(log, iclog, log->l_tail_lsn);
2848 /* cycle incremented when incrementing curr_block */
2849 }
2850
2851 LOG_UNLOCK(log, s);
2852
2853 /*
2854 * We let the log lock go, so it's possible that we hit a log I/O
Nathan Scottc41564b2006-03-29 08:55:14 +10002855 * error or some other SHUTDOWN condition that marks the iclog
Linus Torvalds1da177e2005-04-16 15:20:36 -07002856 * as XLOG_STATE_IOERROR before the bwrite. However, we know that
2857 * this iclog has consistent data, so we ignore IOERROR
2858 * flags after this point.
2859 */
2860 if (sync) {
2861 return xlog_sync(log, iclog);
2862 }
Jesper Juhl014c2542006-01-15 02:37:08 +01002863 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002864
2865} /* xlog_state_release_iclog */
2866
2867
2868/*
2869 * This routine will mark the current iclog in the ring as WANT_SYNC
2870 * and move the current iclog pointer to the next iclog in the ring.
2871 * When this routine is called from xlog_state_get_iclog_space(), the
2872 * exact size of the iclog has not yet been determined. All we know is
2873 * that every data block. We have run out of space in this log record.
2874 */
2875STATIC void
2876xlog_state_switch_iclogs(xlog_t *log,
2877 xlog_in_core_t *iclog,
2878 int eventual_size)
2879{
2880 ASSERT(iclog->ic_state == XLOG_STATE_ACTIVE);
2881 if (!eventual_size)
2882 eventual_size = iclog->ic_offset;
2883 iclog->ic_state = XLOG_STATE_WANT_SYNC;
2884 INT_SET(iclog->ic_header.h_prev_block, ARCH_CONVERT, log->l_prev_block);
2885 log->l_prev_block = log->l_curr_block;
2886 log->l_prev_cycle = log->l_curr_cycle;
2887
2888 /* roll log?: ic_offset changed later */
2889 log->l_curr_block += BTOBB(eventual_size)+BTOBB(log->l_iclog_hsize);
2890
2891 /* Round up to next log-sunit */
2892 if (XFS_SB_VERSION_HASLOGV2(&log->l_mp->m_sb) &&
2893 log->l_mp->m_sb.sb_logsunit > 1) {
2894 __uint32_t sunit_bb = BTOBB(log->l_mp->m_sb.sb_logsunit);
2895 log->l_curr_block = roundup(log->l_curr_block, sunit_bb);
2896 }
2897
2898 if (log->l_curr_block >= log->l_logBBsize) {
2899 log->l_curr_cycle++;
2900 if (log->l_curr_cycle == XLOG_HEADER_MAGIC_NUM)
2901 log->l_curr_cycle++;
2902 log->l_curr_block -= log->l_logBBsize;
2903 ASSERT(log->l_curr_block >= 0);
2904 }
2905 ASSERT(iclog == log->l_iclog);
2906 log->l_iclog = iclog->ic_next;
2907} /* xlog_state_switch_iclogs */
2908
2909
2910/*
2911 * Write out all data in the in-core log as of this exact moment in time.
2912 *
2913 * Data may be written to the in-core log during this call. However,
2914 * we don't guarantee this data will be written out. A change from past
2915 * implementation means this routine will *not* write out zero length LRs.
2916 *
2917 * Basically, we try and perform an intelligent scan of the in-core logs.
2918 * If we determine there is no flushable data, we just return. There is no
2919 * flushable data if:
2920 *
2921 * 1. the current iclog is active and has no data; the previous iclog
2922 * is in the active or dirty state.
2923 * 2. the current iclog is drity, and the previous iclog is in the
2924 * active or dirty state.
2925 *
2926 * We may sleep (call psema) if:
2927 *
2928 * 1. the current iclog is not in the active nor dirty state.
2929 * 2. the current iclog dirty, and the previous iclog is not in the
2930 * active nor dirty state.
2931 * 3. the current iclog is active, and there is another thread writing
2932 * to this particular iclog.
2933 * 4. a) the current iclog is active and has no other writers
2934 * b) when we return from flushing out this iclog, it is still
2935 * not in the active nor dirty state.
2936 */
2937STATIC int
Christoph Hellwigf538d4d2005-11-02 10:26:59 +11002938xlog_state_sync_all(xlog_t *log, uint flags, int *log_flushed)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002939{
2940 xlog_in_core_t *iclog;
2941 xfs_lsn_t lsn;
2942 SPLDECL(s);
2943
2944 s = LOG_LOCK(log);
2945
2946 iclog = log->l_iclog;
2947 if (iclog->ic_state & XLOG_STATE_IOERROR) {
2948 LOG_UNLOCK(log, s);
2949 return XFS_ERROR(EIO);
2950 }
2951
2952 /* If the head iclog is not active nor dirty, we just attach
2953 * ourselves to the head and go to sleep.
2954 */
2955 if (iclog->ic_state == XLOG_STATE_ACTIVE ||
2956 iclog->ic_state == XLOG_STATE_DIRTY) {
2957 /*
2958 * If the head is dirty or (active and empty), then
2959 * we need to look at the previous iclog. If the previous
2960 * iclog is active or dirty we are done. There is nothing
2961 * to sync out. Otherwise, we attach ourselves to the
2962 * previous iclog and go to sleep.
2963 */
2964 if (iclog->ic_state == XLOG_STATE_DIRTY ||
2965 (iclog->ic_refcnt == 0 && iclog->ic_offset == 0)) {
2966 iclog = iclog->ic_prev;
2967 if (iclog->ic_state == XLOG_STATE_ACTIVE ||
2968 iclog->ic_state == XLOG_STATE_DIRTY)
2969 goto no_sleep;
2970 else
2971 goto maybe_sleep;
2972 } else {
2973 if (iclog->ic_refcnt == 0) {
2974 /* We are the only one with access to this
2975 * iclog. Flush it out now. There should
2976 * be a roundoff of zero to show that someone
2977 * has already taken care of the roundoff from
2978 * the previous sync.
2979 */
2980 iclog->ic_refcnt++;
2981 lsn = INT_GET(iclog->ic_header.h_lsn, ARCH_CONVERT);
2982 xlog_state_switch_iclogs(log, iclog, 0);
2983 LOG_UNLOCK(log, s);
2984
2985 if (xlog_state_release_iclog(log, iclog))
2986 return XFS_ERROR(EIO);
Christoph Hellwigf538d4d2005-11-02 10:26:59 +11002987 *log_flushed = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002988 s = LOG_LOCK(log);
2989 if (INT_GET(iclog->ic_header.h_lsn, ARCH_CONVERT) == lsn &&
2990 iclog->ic_state != XLOG_STATE_DIRTY)
2991 goto maybe_sleep;
2992 else
2993 goto no_sleep;
2994 } else {
2995 /* Someone else is writing to this iclog.
2996 * Use its call to flush out the data. However,
2997 * the other thread may not force out this LR,
2998 * so we mark it WANT_SYNC.
2999 */
3000 xlog_state_switch_iclogs(log, iclog, 0);
3001 goto maybe_sleep;
3002 }
3003 }
3004 }
3005
3006 /* By the time we come around again, the iclog could've been filled
3007 * which would give it another lsn. If we have a new lsn, just
3008 * return because the relevant data has been flushed.
3009 */
3010maybe_sleep:
3011 if (flags & XFS_LOG_SYNC) {
3012 /*
3013 * We must check if we're shutting down here, before
3014 * we wait, while we're holding the LOG_LOCK.
3015 * Then we check again after waking up, in case our
3016 * sleep was disturbed by a bad news.
3017 */
3018 if (iclog->ic_state & XLOG_STATE_IOERROR) {
3019 LOG_UNLOCK(log, s);
3020 return XFS_ERROR(EIO);
3021 }
3022 XFS_STATS_INC(xs_log_force_sleep);
3023 sv_wait(&iclog->ic_forcesema, PINOD, &log->l_icloglock, s);
3024 /*
3025 * No need to grab the log lock here since we're
3026 * only deciding whether or not to return EIO
3027 * and the memory read should be atomic.
3028 */
3029 if (iclog->ic_state & XLOG_STATE_IOERROR)
3030 return XFS_ERROR(EIO);
Christoph Hellwigf538d4d2005-11-02 10:26:59 +11003031 *log_flushed = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003032
3033 } else {
3034
3035no_sleep:
3036 LOG_UNLOCK(log, s);
3037 }
3038 return 0;
3039} /* xlog_state_sync_all */
3040
3041
3042/*
3043 * Used by code which implements synchronous log forces.
3044 *
3045 * Find in-core log with lsn.
3046 * If it is in the DIRTY state, just return.
3047 * If it is in the ACTIVE state, move the in-core log into the WANT_SYNC
3048 * state and go to sleep or return.
3049 * If it is in any other state, go to sleep or return.
3050 *
3051 * If filesystem activity goes to zero, the iclog will get flushed only by
3052 * bdflush().
3053 */
3054int
3055xlog_state_sync(xlog_t *log,
3056 xfs_lsn_t lsn,
Christoph Hellwigf538d4d2005-11-02 10:26:59 +11003057 uint flags,
3058 int *log_flushed)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003059{
3060 xlog_in_core_t *iclog;
3061 int already_slept = 0;
3062 SPLDECL(s);
3063
3064
3065try_again:
3066 s = LOG_LOCK(log);
3067 iclog = log->l_iclog;
3068
3069 if (iclog->ic_state & XLOG_STATE_IOERROR) {
3070 LOG_UNLOCK(log, s);
3071 return XFS_ERROR(EIO);
3072 }
3073
3074 do {
3075 if (INT_GET(iclog->ic_header.h_lsn, ARCH_CONVERT) != lsn) {
3076 iclog = iclog->ic_next;
3077 continue;
3078 }
3079
3080 if (iclog->ic_state == XLOG_STATE_DIRTY) {
3081 LOG_UNLOCK(log, s);
3082 return 0;
3083 }
3084
3085 if (iclog->ic_state == XLOG_STATE_ACTIVE) {
3086 /*
3087 * We sleep here if we haven't already slept (e.g.
3088 * this is the first time we've looked at the correct
3089 * iclog buf) and the buffer before us is going to
3090 * be sync'ed. The reason for this is that if we
3091 * are doing sync transactions here, by waiting for
3092 * the previous I/O to complete, we can allow a few
3093 * more transactions into this iclog before we close
3094 * it down.
3095 *
3096 * Otherwise, we mark the buffer WANT_SYNC, and bump
3097 * up the refcnt so we can release the log (which drops
3098 * the ref count). The state switch keeps new transaction
3099 * commits from using this buffer. When the current commits
3100 * finish writing into the buffer, the refcount will drop to
3101 * zero and the buffer will go out then.
3102 */
3103 if (!already_slept &&
3104 (iclog->ic_prev->ic_state & (XLOG_STATE_WANT_SYNC |
3105 XLOG_STATE_SYNCING))) {
3106 ASSERT(!(iclog->ic_state & XLOG_STATE_IOERROR));
3107 XFS_STATS_INC(xs_log_force_sleep);
3108 sv_wait(&iclog->ic_prev->ic_writesema, PSWP,
3109 &log->l_icloglock, s);
Christoph Hellwigf538d4d2005-11-02 10:26:59 +11003110 *log_flushed = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003111 already_slept = 1;
3112 goto try_again;
3113 } else {
3114 iclog->ic_refcnt++;
3115 xlog_state_switch_iclogs(log, iclog, 0);
3116 LOG_UNLOCK(log, s);
3117 if (xlog_state_release_iclog(log, iclog))
3118 return XFS_ERROR(EIO);
Christoph Hellwigf538d4d2005-11-02 10:26:59 +11003119 *log_flushed = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003120 s = LOG_LOCK(log);
3121 }
3122 }
3123
3124 if ((flags & XFS_LOG_SYNC) && /* sleep */
3125 !(iclog->ic_state & (XLOG_STATE_ACTIVE | XLOG_STATE_DIRTY))) {
3126
3127 /*
3128 * Don't wait on the forcesema if we know that we've
3129 * gotten a log write error.
3130 */
3131 if (iclog->ic_state & XLOG_STATE_IOERROR) {
3132 LOG_UNLOCK(log, s);
3133 return XFS_ERROR(EIO);
3134 }
3135 XFS_STATS_INC(xs_log_force_sleep);
3136 sv_wait(&iclog->ic_forcesema, PSWP, &log->l_icloglock, s);
3137 /*
3138 * No need to grab the log lock here since we're
3139 * only deciding whether or not to return EIO
3140 * and the memory read should be atomic.
3141 */
3142 if (iclog->ic_state & XLOG_STATE_IOERROR)
3143 return XFS_ERROR(EIO);
Christoph Hellwigf538d4d2005-11-02 10:26:59 +11003144 *log_flushed = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003145 } else { /* just return */
3146 LOG_UNLOCK(log, s);
3147 }
3148 return 0;
3149
3150 } while (iclog != log->l_iclog);
3151
3152 LOG_UNLOCK(log, s);
Jesper Juhl014c2542006-01-15 02:37:08 +01003153 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003154} /* xlog_state_sync */
3155
3156
3157/*
3158 * Called when we want to mark the current iclog as being ready to sync to
3159 * disk.
3160 */
3161void
3162xlog_state_want_sync(xlog_t *log, xlog_in_core_t *iclog)
3163{
3164 SPLDECL(s);
3165
3166 s = LOG_LOCK(log);
3167
3168 if (iclog->ic_state == XLOG_STATE_ACTIVE) {
3169 xlog_state_switch_iclogs(log, iclog, 0);
3170 } else {
3171 ASSERT(iclog->ic_state &
3172 (XLOG_STATE_WANT_SYNC|XLOG_STATE_IOERROR));
3173 }
3174
3175 LOG_UNLOCK(log, s);
3176} /* xlog_state_want_sync */
3177
3178
3179
3180/*****************************************************************************
3181 *
3182 * TICKET functions
3183 *
3184 *****************************************************************************
3185 */
3186
3187/*
3188 * Algorithm doesn't take into account page size. ;-(
3189 */
3190STATIC void
3191xlog_state_ticket_alloc(xlog_t *log)
3192{
3193 xlog_ticket_t *t_list;
3194 xlog_ticket_t *next;
3195 xfs_caddr_t buf;
3196 uint i = (NBPP / sizeof(xlog_ticket_t)) - 2;
3197 SPLDECL(s);
3198
3199 /*
3200 * The kmem_zalloc may sleep, so we shouldn't be holding the
3201 * global lock. XXXmiken: may want to use zone allocator.
3202 */
3203 buf = (xfs_caddr_t) kmem_zalloc(NBPP, KM_SLEEP);
3204
3205 s = LOG_LOCK(log);
3206
3207 /* Attach 1st ticket to Q, so we can keep track of allocated memory */
3208 t_list = (xlog_ticket_t *)buf;
3209 t_list->t_next = log->l_unmount_free;
3210 log->l_unmount_free = t_list++;
3211 log->l_ticket_cnt++;
3212 log->l_ticket_tcnt++;
3213
3214 /* Next ticket becomes first ticket attached to ticket free list */
3215 if (log->l_freelist != NULL) {
3216 ASSERT(log->l_tail != NULL);
3217 log->l_tail->t_next = t_list;
3218 } else {
3219 log->l_freelist = t_list;
3220 }
3221 log->l_ticket_cnt++;
3222 log->l_ticket_tcnt++;
3223
3224 /* Cycle through rest of alloc'ed memory, building up free Q */
3225 for ( ; i > 0; i--) {
3226 next = t_list + 1;
3227 t_list->t_next = next;
3228 t_list = next;
3229 log->l_ticket_cnt++;
3230 log->l_ticket_tcnt++;
3231 }
3232 t_list->t_next = NULL;
3233 log->l_tail = t_list;
3234 LOG_UNLOCK(log, s);
3235} /* xlog_state_ticket_alloc */
3236
3237
3238/*
3239 * Put ticket into free list
3240 *
3241 * Assumption: log lock is held around this call.
3242 */
3243STATIC void
3244xlog_ticket_put(xlog_t *log,
3245 xlog_ticket_t *ticket)
3246{
3247 sv_destroy(&ticket->t_sema);
3248
3249 /*
3250 * Don't think caching will make that much difference. It's
3251 * more important to make debug easier.
3252 */
3253#if 0
3254 /* real code will want to use LIFO for caching */
3255 ticket->t_next = log->l_freelist;
3256 log->l_freelist = ticket;
3257 /* no need to clear fields */
3258#else
3259 /* When we debug, it is easier if tickets are cycled */
3260 ticket->t_next = NULL;
Christoph Hellwig4b809162007-08-16 15:37:36 +10003261 if (log->l_tail) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07003262 log->l_tail->t_next = ticket;
3263 } else {
Christoph Hellwig4b809162007-08-16 15:37:36 +10003264 ASSERT(log->l_freelist == NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003265 log->l_freelist = ticket;
3266 }
3267 log->l_tail = ticket;
3268#endif /* DEBUG */
3269 log->l_ticket_cnt++;
3270} /* xlog_ticket_put */
3271
3272
3273/*
3274 * Grab ticket off freelist or allocation some more
3275 */
3276xlog_ticket_t *
3277xlog_ticket_get(xlog_t *log,
3278 int unit_bytes,
3279 int cnt,
3280 char client,
3281 uint xflags)
3282{
3283 xlog_ticket_t *tic;
3284 uint num_headers;
3285 SPLDECL(s);
3286
3287 alloc:
3288 if (log->l_freelist == NULL)
3289 xlog_state_ticket_alloc(log); /* potentially sleep */
3290
3291 s = LOG_LOCK(log);
3292 if (log->l_freelist == NULL) {
3293 LOG_UNLOCK(log, s);
3294 goto alloc;
3295 }
3296 tic = log->l_freelist;
3297 log->l_freelist = tic->t_next;
3298 if (log->l_freelist == NULL)
3299 log->l_tail = NULL;
3300 log->l_ticket_cnt--;
3301 LOG_UNLOCK(log, s);
3302
3303 /*
3304 * Permanent reservations have up to 'cnt'-1 active log operations
3305 * in the log. A unit in this case is the amount of space for one
3306 * of these log operations. Normal reservations have a cnt of 1
3307 * and their unit amount is the total amount of space required.
3308 *
3309 * The following lines of code account for non-transaction data
Tim Shimmin32fb9b52005-09-02 16:41:43 +10003310 * which occupy space in the on-disk log.
3311 *
3312 * Normal form of a transaction is:
3313 * <oph><trans-hdr><start-oph><reg1-oph><reg1><reg2-oph>...<commit-oph>
3314 * and then there are LR hdrs, split-recs and roundoff at end of syncs.
3315 *
3316 * We need to account for all the leadup data and trailer data
3317 * around the transaction data.
3318 * And then we need to account for the worst case in terms of using
3319 * more space.
3320 * The worst case will happen if:
3321 * - the placement of the transaction happens to be such that the
3322 * roundoff is at its maximum
3323 * - the transaction data is synced before the commit record is synced
3324 * i.e. <transaction-data><roundoff> | <commit-rec><roundoff>
3325 * Therefore the commit record is in its own Log Record.
3326 * This can happen as the commit record is called with its
3327 * own region to xlog_write().
3328 * This then means that in the worst case, roundoff can happen for
3329 * the commit-rec as well.
3330 * The commit-rec is smaller than padding in this scenario and so it is
3331 * not added separately.
Linus Torvalds1da177e2005-04-16 15:20:36 -07003332 */
3333
Tim Shimmin32fb9b52005-09-02 16:41:43 +10003334 /* for trans header */
Linus Torvalds1da177e2005-04-16 15:20:36 -07003335 unit_bytes += sizeof(xlog_op_header_t);
Tim Shimmin32fb9b52005-09-02 16:41:43 +10003336 unit_bytes += sizeof(xfs_trans_header_t);
3337
3338 /* for start-rec */
3339 unit_bytes += sizeof(xlog_op_header_t);
3340
Linus Torvalds1da177e2005-04-16 15:20:36 -07003341 /* for LR headers */
3342 num_headers = ((unit_bytes + log->l_iclog_size-1) >> log->l_iclog_size_log);
3343 unit_bytes += log->l_iclog_hsize * num_headers;
3344
Tim Shimmin32fb9b52005-09-02 16:41:43 +10003345 /* for commit-rec LR header - note: padding will subsume the ophdr */
3346 unit_bytes += log->l_iclog_hsize;
3347
3348 /* for split-recs - ophdrs added when data split over LRs */
3349 unit_bytes += sizeof(xlog_op_header_t) * num_headers;
3350
3351 /* for roundoff padding for transaction data and one for commit record */
3352 if (XFS_SB_VERSION_HASLOGV2(&log->l_mp->m_sb) &&
3353 log->l_mp->m_sb.sb_logsunit > 1) {
3354 /* log su roundoff */
3355 unit_bytes += 2*log->l_mp->m_sb.sb_logsunit;
3356 } else {
3357 /* BB roundoff */
3358 unit_bytes += 2*BBSIZE;
3359 }
3360
Linus Torvalds1da177e2005-04-16 15:20:36 -07003361 tic->t_unit_res = unit_bytes;
3362 tic->t_curr_res = unit_bytes;
3363 tic->t_cnt = cnt;
3364 tic->t_ocnt = cnt;
3365 tic->t_tid = (xlog_tid_t)((__psint_t)tic & 0xffffffff);
3366 tic->t_clientid = client;
3367 tic->t_flags = XLOG_TIC_INITED;
Tim Shimmin7e9c6392005-09-02 16:42:05 +10003368 tic->t_trans_type = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003369 if (xflags & XFS_LOG_PERM_RESERV)
3370 tic->t_flags |= XLOG_TIC_PERM_RESERV;
3371 sv_init(&(tic->t_sema), SV_DEFAULT, "logtick");
3372
Christoph Hellwig0adba532007-08-30 17:21:46 +10003373 xlog_tic_reset_res(tic);
Tim Shimmin7e9c6392005-09-02 16:42:05 +10003374
Linus Torvalds1da177e2005-04-16 15:20:36 -07003375 return tic;
3376} /* xlog_ticket_get */
3377
3378
3379/******************************************************************************
3380 *
3381 * Log debug routines
3382 *
3383 ******************************************************************************
3384 */
Nathan Scottcfcbbbd2005-11-02 15:12:04 +11003385#if defined(DEBUG)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003386/*
3387 * Make sure that the destination ptr is within the valid data region of
3388 * one of the iclogs. This uses backup pointers stored in a different
3389 * part of the log in case we trash the log structure.
3390 */
3391void
3392xlog_verify_dest_ptr(xlog_t *log,
3393 __psint_t ptr)
3394{
3395 int i;
3396 int good_ptr = 0;
3397
3398 for (i=0; i < log->l_iclog_bufs; i++) {
3399 if (ptr >= (__psint_t)log->l_iclog_bak[i] &&
3400 ptr <= (__psint_t)log->l_iclog_bak[i]+log->l_iclog_size)
3401 good_ptr++;
3402 }
3403 if (! good_ptr)
3404 xlog_panic("xlog_verify_dest_ptr: invalid ptr");
3405} /* xlog_verify_dest_ptr */
3406
3407STATIC void
3408xlog_verify_grant_head(xlog_t *log, int equals)
3409{
3410 if (log->l_grant_reserve_cycle == log->l_grant_write_cycle) {
3411 if (equals)
3412 ASSERT(log->l_grant_reserve_bytes >= log->l_grant_write_bytes);
3413 else
3414 ASSERT(log->l_grant_reserve_bytes > log->l_grant_write_bytes);
3415 } else {
3416 ASSERT(log->l_grant_reserve_cycle-1 == log->l_grant_write_cycle);
3417 ASSERT(log->l_grant_write_bytes >= log->l_grant_reserve_bytes);
3418 }
3419} /* xlog_verify_grant_head */
3420
3421/* check if it will fit */
3422STATIC void
3423xlog_verify_tail_lsn(xlog_t *log,
3424 xlog_in_core_t *iclog,
3425 xfs_lsn_t tail_lsn)
3426{
3427 int blocks;
3428
3429 if (CYCLE_LSN(tail_lsn) == log->l_prev_cycle) {
3430 blocks =
3431 log->l_logBBsize - (log->l_prev_block - BLOCK_LSN(tail_lsn));
3432 if (blocks < BTOBB(iclog->ic_offset)+BTOBB(log->l_iclog_hsize))
3433 xlog_panic("xlog_verify_tail_lsn: ran out of log space");
3434 } else {
3435 ASSERT(CYCLE_LSN(tail_lsn)+1 == log->l_prev_cycle);
3436
3437 if (BLOCK_LSN(tail_lsn) == log->l_prev_block)
3438 xlog_panic("xlog_verify_tail_lsn: tail wrapped");
3439
3440 blocks = BLOCK_LSN(tail_lsn) - log->l_prev_block;
3441 if (blocks < BTOBB(iclog->ic_offset) + 1)
3442 xlog_panic("xlog_verify_tail_lsn: ran out of log space");
3443 }
3444} /* xlog_verify_tail_lsn */
3445
3446/*
3447 * Perform a number of checks on the iclog before writing to disk.
3448 *
3449 * 1. Make sure the iclogs are still circular
3450 * 2. Make sure we have a good magic number
3451 * 3. Make sure we don't have magic numbers in the data
3452 * 4. Check fields of each log operation header for:
3453 * A. Valid client identifier
3454 * B. tid ptr value falls in valid ptr space (user space code)
3455 * C. Length in log record header is correct according to the
3456 * individual operation headers within record.
3457 * 5. When a bwrite will occur within 5 blocks of the front of the physical
3458 * log, check the preceding blocks of the physical log to make sure all
3459 * the cycle numbers agree with the current cycle number.
3460 */
3461STATIC void
3462xlog_verify_iclog(xlog_t *log,
3463 xlog_in_core_t *iclog,
3464 int count,
3465 boolean_t syncing)
3466{
3467 xlog_op_header_t *ophead;
3468 xlog_in_core_t *icptr;
3469 xlog_in_core_2_t *xhdr;
3470 xfs_caddr_t ptr;
3471 xfs_caddr_t base_ptr;
3472 __psint_t field_offset;
3473 __uint8_t clientid;
3474 int len, i, j, k, op_len;
3475 int idx;
3476 SPLDECL(s);
3477
3478 /* check validity of iclog pointers */
3479 s = LOG_LOCK(log);
3480 icptr = log->l_iclog;
3481 for (i=0; i < log->l_iclog_bufs; i++) {
Christoph Hellwig4b809162007-08-16 15:37:36 +10003482 if (icptr == NULL)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003483 xlog_panic("xlog_verify_iclog: invalid ptr");
3484 icptr = icptr->ic_next;
3485 }
3486 if (icptr != log->l_iclog)
3487 xlog_panic("xlog_verify_iclog: corrupt iclog ring");
3488 LOG_UNLOCK(log, s);
3489
3490 /* check log magic numbers */
3491 ptr = (xfs_caddr_t) &(iclog->ic_header);
3492 if (INT_GET(*(uint *)ptr, ARCH_CONVERT) != XLOG_HEADER_MAGIC_NUM)
3493 xlog_panic("xlog_verify_iclog: invalid magic num");
3494
3495 for (ptr += BBSIZE; ptr < ((xfs_caddr_t)&(iclog->ic_header))+count;
3496 ptr += BBSIZE) {
3497 if (INT_GET(*(uint *)ptr, ARCH_CONVERT) == XLOG_HEADER_MAGIC_NUM)
3498 xlog_panic("xlog_verify_iclog: unexpected magic num");
3499 }
3500
3501 /* check fields */
3502 len = INT_GET(iclog->ic_header.h_num_logops, ARCH_CONVERT);
3503 ptr = iclog->ic_datap;
3504 base_ptr = ptr;
3505 ophead = (xlog_op_header_t *)ptr;
3506 xhdr = (xlog_in_core_2_t *)&iclog->ic_header;
3507 for (i = 0; i < len; i++) {
3508 ophead = (xlog_op_header_t *)ptr;
3509
3510 /* clientid is only 1 byte */
3511 field_offset = (__psint_t)
3512 ((xfs_caddr_t)&(ophead->oh_clientid) - base_ptr);
3513 if (syncing == B_FALSE || (field_offset & 0x1ff)) {
3514 clientid = ophead->oh_clientid;
3515 } else {
3516 idx = BTOBBT((xfs_caddr_t)&(ophead->oh_clientid) - iclog->ic_datap);
3517 if (idx >= (XLOG_HEADER_CYCLE_SIZE / BBSIZE)) {
3518 j = idx / (XLOG_HEADER_CYCLE_SIZE / BBSIZE);
3519 k = idx % (XLOG_HEADER_CYCLE_SIZE / BBSIZE);
3520 clientid = GET_CLIENT_ID(xhdr[j].hic_xheader.xh_cycle_data[k], ARCH_CONVERT);
3521 } else {
3522 clientid = GET_CLIENT_ID(iclog->ic_header.h_cycle_data[idx], ARCH_CONVERT);
3523 }
3524 }
3525 if (clientid != XFS_TRANSACTION && clientid != XFS_LOG)
Christoph Hellwigda1650a2005-11-02 10:21:35 +11003526 cmn_err(CE_WARN, "xlog_verify_iclog: "
3527 "invalid clientid %d op 0x%p offset 0x%lx",
3528 clientid, ophead, (unsigned long)field_offset);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003529
3530 /* check length */
3531 field_offset = (__psint_t)
3532 ((xfs_caddr_t)&(ophead->oh_len) - base_ptr);
3533 if (syncing == B_FALSE || (field_offset & 0x1ff)) {
3534 op_len = INT_GET(ophead->oh_len, ARCH_CONVERT);
3535 } else {
3536 idx = BTOBBT((__psint_t)&ophead->oh_len -
3537 (__psint_t)iclog->ic_datap);
3538 if (idx >= (XLOG_HEADER_CYCLE_SIZE / BBSIZE)) {
3539 j = idx / (XLOG_HEADER_CYCLE_SIZE / BBSIZE);
3540 k = idx % (XLOG_HEADER_CYCLE_SIZE / BBSIZE);
3541 op_len = INT_GET(xhdr[j].hic_xheader.xh_cycle_data[k], ARCH_CONVERT);
3542 } else {
3543 op_len = INT_GET(iclog->ic_header.h_cycle_data[idx], ARCH_CONVERT);
3544 }
3545 }
3546 ptr += sizeof(xlog_op_header_t) + op_len;
3547 }
3548} /* xlog_verify_iclog */
Nathan Scottcfcbbbd2005-11-02 15:12:04 +11003549#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07003550
3551/*
3552 * Mark all iclogs IOERROR. LOG_LOCK is held by the caller.
3553 */
3554STATIC int
3555xlog_state_ioerror(
3556 xlog_t *log)
3557{
3558 xlog_in_core_t *iclog, *ic;
3559
3560 iclog = log->l_iclog;
3561 if (! (iclog->ic_state & XLOG_STATE_IOERROR)) {
3562 /*
3563 * Mark all the incore logs IOERROR.
3564 * From now on, no log flushes will result.
3565 */
3566 ic = iclog;
3567 do {
3568 ic->ic_state = XLOG_STATE_IOERROR;
3569 ic = ic->ic_next;
3570 } while (ic != iclog);
Jesper Juhl014c2542006-01-15 02:37:08 +01003571 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003572 }
3573 /*
3574 * Return non-zero, if state transition has already happened.
3575 */
Jesper Juhl014c2542006-01-15 02:37:08 +01003576 return 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003577}
3578
3579/*
3580 * This is called from xfs_force_shutdown, when we're forcibly
3581 * shutting down the filesystem, typically because of an IO error.
3582 * Our main objectives here are to make sure that:
3583 * a. the filesystem gets marked 'SHUTDOWN' for all interested
3584 * parties to find out, 'atomically'.
3585 * b. those who're sleeping on log reservations, pinned objects and
3586 * other resources get woken up, and be told the bad news.
3587 * c. nothing new gets queued up after (a) and (b) are done.
3588 * d. if !logerror, flush the iclogs to disk, then seal them off
3589 * for business.
3590 */
3591int
3592xfs_log_force_umount(
3593 struct xfs_mount *mp,
3594 int logerror)
3595{
3596 xlog_ticket_t *tic;
3597 xlog_t *log;
3598 int retval;
Christoph Hellwigf538d4d2005-11-02 10:26:59 +11003599 int dummy;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003600 SPLDECL(s);
3601 SPLDECL(s2);
3602
3603 log = mp->m_log;
3604
3605 /*
3606 * If this happens during log recovery, don't worry about
3607 * locking; the log isn't open for business yet.
3608 */
3609 if (!log ||
3610 log->l_flags & XLOG_ACTIVE_RECOVERY) {
3611 mp->m_flags |= XFS_MOUNT_FS_SHUTDOWN;
3612 XFS_BUF_DONE(mp->m_sb_bp);
Jesper Juhl014c2542006-01-15 02:37:08 +01003613 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003614 }
3615
3616 /*
3617 * Somebody could've already done the hard work for us.
3618 * No need to get locks for this.
3619 */
3620 if (logerror && log->l_iclog->ic_state & XLOG_STATE_IOERROR) {
3621 ASSERT(XLOG_FORCED_SHUTDOWN(log));
Jesper Juhl014c2542006-01-15 02:37:08 +01003622 return 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003623 }
3624 retval = 0;
3625 /*
3626 * We must hold both the GRANT lock and the LOG lock,
3627 * before we mark the filesystem SHUTDOWN and wake
3628 * everybody up to tell the bad news.
3629 */
3630 s = GRANT_LOCK(log);
3631 s2 = LOG_LOCK(log);
3632 mp->m_flags |= XFS_MOUNT_FS_SHUTDOWN;
3633 XFS_BUF_DONE(mp->m_sb_bp);
3634 /*
3635 * This flag is sort of redundant because of the mount flag, but
3636 * it's good to maintain the separation between the log and the rest
3637 * of XFS.
3638 */
3639 log->l_flags |= XLOG_IO_ERROR;
3640
3641 /*
3642 * If we hit a log error, we want to mark all the iclogs IOERROR
3643 * while we're still holding the loglock.
3644 */
3645 if (logerror)
3646 retval = xlog_state_ioerror(log);
3647 LOG_UNLOCK(log, s2);
3648
3649 /*
3650 * We don't want anybody waiting for log reservations
3651 * after this. That means we have to wake up everybody
3652 * queued up on reserve_headq as well as write_headq.
3653 * In addition, we make sure in xlog_{re}grant_log_space
3654 * that we don't enqueue anything once the SHUTDOWN flag
3655 * is set, and this action is protected by the GRANTLOCK.
3656 */
3657 if ((tic = log->l_reserve_headq)) {
3658 do {
3659 sv_signal(&tic->t_sema);
3660 tic = tic->t_next;
3661 } while (tic != log->l_reserve_headq);
3662 }
3663
3664 if ((tic = log->l_write_headq)) {
3665 do {
3666 sv_signal(&tic->t_sema);
3667 tic = tic->t_next;
3668 } while (tic != log->l_write_headq);
3669 }
3670 GRANT_UNLOCK(log, s);
3671
3672 if (! (log->l_iclog->ic_state & XLOG_STATE_IOERROR)) {
3673 ASSERT(!logerror);
3674 /*
3675 * Force the incore logs to disk before shutting the
3676 * log down completely.
3677 */
Christoph Hellwigf538d4d2005-11-02 10:26:59 +11003678 xlog_state_sync_all(log, XFS_LOG_FORCE|XFS_LOG_SYNC, &dummy);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003679 s2 = LOG_LOCK(log);
3680 retval = xlog_state_ioerror(log);
3681 LOG_UNLOCK(log, s2);
3682 }
3683 /*
3684 * Wake up everybody waiting on xfs_log_force.
3685 * Callback all log item committed functions as if the
3686 * log writes were completed.
3687 */
3688 xlog_state_do_callback(log, XFS_LI_ABORTED, NULL);
3689
3690#ifdef XFSERRORDEBUG
3691 {
3692 xlog_in_core_t *iclog;
3693
3694 s = LOG_LOCK(log);
3695 iclog = log->l_iclog;
3696 do {
3697 ASSERT(iclog->ic_callback == 0);
3698 iclog = iclog->ic_next;
3699 } while (iclog != log->l_iclog);
3700 LOG_UNLOCK(log, s);
3701 }
3702#endif
3703 /* return non-zero if log IOERROR transition had already happened */
Jesper Juhl014c2542006-01-15 02:37:08 +01003704 return retval;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003705}
3706
Christoph Hellwigba0f32d2005-06-21 15:36:52 +10003707STATIC int
Linus Torvalds1da177e2005-04-16 15:20:36 -07003708xlog_iclogs_empty(xlog_t *log)
3709{
3710 xlog_in_core_t *iclog;
3711
3712 iclog = log->l_iclog;
3713 do {
3714 /* endianness does not matter here, zero is zero in
3715 * any language.
3716 */
3717 if (iclog->ic_header.h_num_logops)
Jesper Juhl014c2542006-01-15 02:37:08 +01003718 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003719 iclog = iclog->ic_next;
3720 } while (iclog != log->l_iclog);
Jesper Juhl014c2542006-01-15 02:37:08 +01003721 return 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003722}