xref: /openbmc/linux/fs/gfs2/glops.c (revision 1a14d3a68f04527546121eb7b45187ff6af63151)
1 /*
2  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
3  * Copyright (C) 2004-2006 Red Hat, Inc.  All rights reserved.
4  *
5  * This copyrighted material is made available to anyone wishing to use,
6  * modify, copy, or redistribute it subject to the terms and conditions
7  * of the GNU General Public License version 2.
8  */
9 
10 #include <linux/sched.h>
11 #include <linux/slab.h>
12 #include <linux/spinlock.h>
13 #include <linux/completion.h>
14 #include <linux/buffer_head.h>
15 #include <linux/gfs2_ondisk.h>
16 #include <linux/lm_interface.h>
17 
18 #include "gfs2.h"
19 #include "incore.h"
20 #include "bmap.h"
21 #include "glock.h"
22 #include "glops.h"
23 #include "inode.h"
24 #include "log.h"
25 #include "meta_io.h"
26 #include "recovery.h"
27 #include "rgrp.h"
28 #include "util.h"
29 #include "trans.h"
30 
31 /**
32  * ail_empty_gl - remove all buffers for a given lock from the AIL
33  * @gl: the glock
34  *
35  * None of the buffers should be dirty, locked, or pinned.
36  */
37 
38 static void gfs2_ail_empty_gl(struct gfs2_glock *gl)
39 {
40 	struct gfs2_sbd *sdp = gl->gl_sbd;
41 	unsigned int blocks;
42 	struct list_head *head = &gl->gl_ail_list;
43 	struct gfs2_bufdata *bd;
44 	struct buffer_head *bh;
45 	u64 blkno;
46 	int error;
47 
48 	blocks = atomic_read(&gl->gl_ail_count);
49 	if (!blocks)
50 		return;
51 
52 	error = gfs2_trans_begin(sdp, 0, blocks);
53 	if (gfs2_assert_withdraw(sdp, !error))
54 		return;
55 
56 	gfs2_log_lock(sdp);
57 	while (!list_empty(head)) {
58 		bd = list_entry(head->next, struct gfs2_bufdata,
59 				bd_ail_gl_list);
60 		bh = bd->bd_bh;
61 		blkno = bh->b_blocknr;
62 		gfs2_assert_withdraw(sdp, !buffer_busy(bh));
63 
64 		bd->bd_ail = NULL;
65 		list_del(&bd->bd_ail_st_list);
66 		list_del(&bd->bd_ail_gl_list);
67 		atomic_dec(&gl->gl_ail_count);
68 		brelse(bh);
69 		gfs2_log_unlock(sdp);
70 
71 		gfs2_trans_add_revoke(sdp, blkno);
72 
73 		gfs2_log_lock(sdp);
74 	}
75 	gfs2_assert_withdraw(sdp, !atomic_read(&gl->gl_ail_count));
76 	gfs2_log_unlock(sdp);
77 
78 	gfs2_trans_end(sdp);
79 	gfs2_log_flush(sdp, NULL);
80 }
81 
82 /**
83  * gfs2_pte_inval - Sync and invalidate all PTEs associated with a glock
84  * @gl: the glock
85  *
86  */
87 
88 static void gfs2_pte_inval(struct gfs2_glock *gl)
89 {
90 	struct gfs2_inode *ip;
91 	struct inode *inode;
92 
93 	ip = gl->gl_object;
94 	inode = &ip->i_inode;
95 	if (!ip || !S_ISREG(inode->i_mode))
96 		return;
97 
98 	if (!test_bit(GIF_PAGED, &ip->i_flags))
99 		return;
100 
101 	unmap_shared_mapping_range(inode->i_mapping, 0, 0);
102 
103 	if (test_bit(GIF_SW_PAGED, &ip->i_flags))
104 		set_bit(GLF_DIRTY, &gl->gl_flags);
105 
106 	clear_bit(GIF_SW_PAGED, &ip->i_flags);
107 }
108 
109 /**
110  * gfs2_page_inval - Invalidate all pages associated with a glock
111  * @gl: the glock
112  *
113  */
114 
115 static void gfs2_page_inval(struct gfs2_glock *gl)
116 {
117 	struct gfs2_inode *ip;
118 	struct inode *inode;
119 
120 	ip = gl->gl_object;
121 	inode = &ip->i_inode;
122 	if (!ip || !S_ISREG(inode->i_mode))
123 		return;
124 
125 	truncate_inode_pages(inode->i_mapping, 0);
126 	gfs2_assert_withdraw(GFS2_SB(&ip->i_inode), !inode->i_mapping->nrpages);
127 	clear_bit(GIF_PAGED, &ip->i_flags);
128 }
129 
130 /**
131  * gfs2_page_wait - Wait for writeback of data
132  * @gl: the glock
133  *
134  * Syncs data (not metadata) for a regular file.
135  * No-op for all other types.
136  */
137 
138 static void gfs2_page_wait(struct gfs2_glock *gl)
139 {
140 	struct gfs2_inode *ip = gl->gl_object;
141 	struct inode *inode = &ip->i_inode;
142 	struct address_space *mapping = inode->i_mapping;
143 	int error;
144 
145 	if (!S_ISREG(inode->i_mode))
146 		return;
147 
148 	error = filemap_fdatawait(mapping);
149 
150 	/* Put back any errors cleared by filemap_fdatawait()
151 	   so they can be caught by someone who can pass them
152 	   up to user space. */
153 
154 	if (error == -ENOSPC)
155 		set_bit(AS_ENOSPC, &mapping->flags);
156 	else if (error)
157 		set_bit(AS_EIO, &mapping->flags);
158 
159 }
160 
161 static void gfs2_page_writeback(struct gfs2_glock *gl)
162 {
163 	struct gfs2_inode *ip = gl->gl_object;
164 	struct inode *inode = &ip->i_inode;
165 	struct address_space *mapping = inode->i_mapping;
166 
167 	if (!S_ISREG(inode->i_mode))
168 		return;
169 
170 	filemap_fdatawrite(mapping);
171 }
172 
173 /**
174  * meta_go_sync - sync out the metadata for this glock
175  * @gl: the glock
176  *
177  * Called when demoting or unlocking an EX glock.  We must flush
178  * to disk all dirty buffers/pages relating to this glock, and must not
179  * not return to caller to demote/unlock the glock until I/O is complete.
180  */
181 
182 static void meta_go_sync(struct gfs2_glock *gl)
183 {
184 	if (test_and_clear_bit(GLF_DIRTY, &gl->gl_flags)) {
185 		gfs2_log_flush(gl->gl_sbd, gl);
186 		gfs2_meta_sync(gl);
187 		gfs2_ail_empty_gl(gl);
188 	}
189 
190 }
191 
192 /**
193  * meta_go_inval - invalidate the metadata for this glock
194  * @gl: the glock
195  * @flags:
196  *
197  */
198 
199 static void meta_go_inval(struct gfs2_glock *gl, int flags)
200 {
201 	if (!(flags & DIO_METADATA))
202 		return;
203 
204 	gfs2_meta_inval(gl);
205 	gl->gl_vn++;
206 }
207 
208 /**
209  * inode_go_xmote_th - promote/demote a glock
210  * @gl: the glock
211  * @state: the requested state
212  * @flags:
213  *
214  */
215 
216 static void inode_go_xmote_th(struct gfs2_glock *gl, unsigned int state,
217 			      int flags)
218 {
219 	if (gl->gl_state != LM_ST_UNLOCKED)
220 		gfs2_pte_inval(gl);
221 	gfs2_glock_xmote_th(gl, state, flags);
222 }
223 
224 /**
225  * inode_go_xmote_bh - After promoting/demoting a glock
226  * @gl: the glock
227  *
228  */
229 
230 static void inode_go_xmote_bh(struct gfs2_glock *gl)
231 {
232 	struct gfs2_holder *gh = gl->gl_req_gh;
233 	struct buffer_head *bh;
234 	int error;
235 
236 	if (gl->gl_state != LM_ST_UNLOCKED &&
237 	    (!gh || !(gh->gh_flags & GL_SKIP))) {
238 		error = gfs2_meta_read(gl, gl->gl_name.ln_number, 0, &bh);
239 		if (!error)
240 			brelse(bh);
241 	}
242 }
243 
244 /**
245  * inode_go_drop_th - unlock a glock
246  * @gl: the glock
247  *
248  * Invoked from rq_demote().
249  * Another node needs the lock in EXCLUSIVE mode, or lock (unused for too long)
250  * is being purged from our node's glock cache; we're dropping lock.
251  */
252 
253 static void inode_go_drop_th(struct gfs2_glock *gl)
254 {
255 	gfs2_pte_inval(gl);
256 	gfs2_glock_drop_th(gl);
257 }
258 
259 /**
260  * inode_go_sync - Sync the dirty data and/or metadata for an inode glock
261  * @gl: the glock protecting the inode
262  *
263  */
264 
265 static void inode_go_sync(struct gfs2_glock *gl)
266 {
267 	if (test_bit(GLF_DIRTY, &gl->gl_flags)) {
268 		gfs2_page_writeback(gl);
269 		gfs2_log_flush(gl->gl_sbd, gl);
270 		gfs2_meta_sync(gl);
271 		gfs2_page_wait(gl);
272 		clear_bit(GLF_DIRTY, &gl->gl_flags);
273 		gfs2_ail_empty_gl(gl);
274 	}
275 }
276 
277 /**
278  * inode_go_inval - prepare a inode glock to be released
279  * @gl: the glock
280  * @flags:
281  *
282  */
283 
284 static void inode_go_inval(struct gfs2_glock *gl, int flags)
285 {
286 	int meta = (flags & DIO_METADATA);
287 
288 	if (meta) {
289 		struct gfs2_inode *ip = gl->gl_object;
290 		gfs2_meta_inval(gl);
291 		set_bit(GIF_INVALID, &ip->i_flags);
292 	}
293 	gfs2_page_inval(gl);
294 }
295 
296 /**
297  * inode_go_demote_ok - Check to see if it's ok to unlock an inode glock
298  * @gl: the glock
299  *
300  * Returns: 1 if it's ok
301  */
302 
303 static int inode_go_demote_ok(struct gfs2_glock *gl)
304 {
305 	struct gfs2_sbd *sdp = gl->gl_sbd;
306 	int demote = 0;
307 
308 	if (!gl->gl_object && !gl->gl_aspace->i_mapping->nrpages)
309 		demote = 1;
310 	else if (!sdp->sd_args.ar_localcaching &&
311 		 time_after_eq(jiffies, gl->gl_stamp +
312 			       gfs2_tune_get(sdp, gt_demote_secs) * HZ))
313 		demote = 1;
314 
315 	return demote;
316 }
317 
318 /**
319  * inode_go_lock - operation done after an inode lock is locked by a process
320  * @gl: the glock
321  * @flags:
322  *
323  * Returns: errno
324  */
325 
326 static int inode_go_lock(struct gfs2_holder *gh)
327 {
328 	struct gfs2_glock *gl = gh->gh_gl;
329 	struct gfs2_inode *ip = gl->gl_object;
330 	int error = 0;
331 
332 	if (!ip)
333 		return 0;
334 
335 	if (test_bit(GIF_INVALID, &ip->i_flags)) {
336 		error = gfs2_inode_refresh(ip);
337 		if (error)
338 			return error;
339 	}
340 
341 	if ((ip->i_di.di_flags & GFS2_DIF_TRUNC_IN_PROG) &&
342 	    (gl->gl_state == LM_ST_EXCLUSIVE) &&
343 	    (gh->gh_flags & GL_LOCAL_EXCL))
344 		error = gfs2_truncatei_resume(ip);
345 
346 	return error;
347 }
348 
349 /**
350  * inode_go_unlock - operation done before an inode lock is unlocked by a
351  *		     process
352  * @gl: the glock
353  * @flags:
354  *
355  */
356 
357 static void inode_go_unlock(struct gfs2_holder *gh)
358 {
359 	struct gfs2_glock *gl = gh->gh_gl;
360 	struct gfs2_inode *ip = gl->gl_object;
361 
362 	if (ip)
363 		gfs2_meta_cache_flush(ip);
364 }
365 
366 /**
367  * inode_greedy -
368  * @gl: the glock
369  *
370  */
371 
372 static void inode_greedy(struct gfs2_glock *gl)
373 {
374 	struct gfs2_sbd *sdp = gl->gl_sbd;
375 	struct gfs2_inode *ip = gl->gl_object;
376 	unsigned int quantum = gfs2_tune_get(sdp, gt_greedy_quantum);
377 	unsigned int max = gfs2_tune_get(sdp, gt_greedy_max);
378 	unsigned int new_time;
379 
380 	spin_lock(&ip->i_spin);
381 
382 	if (time_after(ip->i_last_pfault + quantum, jiffies)) {
383 		new_time = ip->i_greedy + quantum;
384 		if (new_time > max)
385 			new_time = max;
386 	} else {
387 		new_time = ip->i_greedy - quantum;
388 		if (!new_time || new_time > max)
389 			new_time = 1;
390 	}
391 
392 	ip->i_greedy = new_time;
393 
394 	spin_unlock(&ip->i_spin);
395 
396 	iput(&ip->i_inode);
397 }
398 
399 /**
400  * rgrp_go_demote_ok - Check to see if it's ok to unlock a RG's glock
401  * @gl: the glock
402  *
403  * Returns: 1 if it's ok
404  */
405 
406 static int rgrp_go_demote_ok(struct gfs2_glock *gl)
407 {
408 	return !gl->gl_aspace->i_mapping->nrpages;
409 }
410 
411 /**
412  * rgrp_go_lock - operation done after an rgrp lock is locked by
413  *    a first holder on this node.
414  * @gl: the glock
415  * @flags:
416  *
417  * Returns: errno
418  */
419 
420 static int rgrp_go_lock(struct gfs2_holder *gh)
421 {
422 	return gfs2_rgrp_bh_get(gh->gh_gl->gl_object);
423 }
424 
425 /**
426  * rgrp_go_unlock - operation done before an rgrp lock is unlocked by
427  *    a last holder on this node.
428  * @gl: the glock
429  * @flags:
430  *
431  */
432 
433 static void rgrp_go_unlock(struct gfs2_holder *gh)
434 {
435 	gfs2_rgrp_bh_put(gh->gh_gl->gl_object);
436 }
437 
438 /**
439  * trans_go_xmote_th - promote/demote the transaction glock
440  * @gl: the glock
441  * @state: the requested state
442  * @flags:
443  *
444  */
445 
446 static void trans_go_xmote_th(struct gfs2_glock *gl, unsigned int state,
447 			      int flags)
448 {
449 	struct gfs2_sbd *sdp = gl->gl_sbd;
450 
451 	if (gl->gl_state != LM_ST_UNLOCKED &&
452 	    test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags)) {
453 		gfs2_meta_syncfs(sdp);
454 		gfs2_log_shutdown(sdp);
455 	}
456 
457 	gfs2_glock_xmote_th(gl, state, flags);
458 }
459 
460 /**
461  * trans_go_xmote_bh - After promoting/demoting the transaction glock
462  * @gl: the glock
463  *
464  */
465 
466 static void trans_go_xmote_bh(struct gfs2_glock *gl)
467 {
468 	struct gfs2_sbd *sdp = gl->gl_sbd;
469 	struct gfs2_inode *ip = GFS2_I(sdp->sd_jdesc->jd_inode);
470 	struct gfs2_glock *j_gl = ip->i_gl;
471 	struct gfs2_log_header_host head;
472 	int error;
473 
474 	if (gl->gl_state != LM_ST_UNLOCKED &&
475 	    test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags)) {
476 		gfs2_meta_cache_flush(GFS2_I(sdp->sd_jdesc->jd_inode));
477 		j_gl->gl_ops->go_inval(j_gl, DIO_METADATA);
478 
479 		error = gfs2_find_jhead(sdp->sd_jdesc, &head);
480 		if (error)
481 			gfs2_consist(sdp);
482 		if (!(head.lh_flags & GFS2_LOG_HEAD_UNMOUNT))
483 			gfs2_consist(sdp);
484 
485 		/*  Initialize some head of the log stuff  */
486 		if (!test_bit(SDF_SHUTDOWN, &sdp->sd_flags)) {
487 			sdp->sd_log_sequence = head.lh_sequence + 1;
488 			gfs2_log_pointers_init(sdp, head.lh_blkno);
489 		}
490 	}
491 }
492 
493 /**
494  * trans_go_drop_th - unlock the transaction glock
495  * @gl: the glock
496  *
497  * We want to sync the device even with localcaching.  Remember
498  * that localcaching journal replay only marks buffers dirty.
499  */
500 
501 static void trans_go_drop_th(struct gfs2_glock *gl)
502 {
503 	struct gfs2_sbd *sdp = gl->gl_sbd;
504 
505 	if (test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags)) {
506 		gfs2_meta_syncfs(sdp);
507 		gfs2_log_shutdown(sdp);
508 	}
509 
510 	gfs2_glock_drop_th(gl);
511 }
512 
513 /**
514  * quota_go_demote_ok - Check to see if it's ok to unlock a quota glock
515  * @gl: the glock
516  *
517  * Returns: 1 if it's ok
518  */
519 
520 static int quota_go_demote_ok(struct gfs2_glock *gl)
521 {
522 	return !atomic_read(&gl->gl_lvb_count);
523 }
524 
525 const struct gfs2_glock_operations gfs2_meta_glops = {
526 	.go_xmote_th = gfs2_glock_xmote_th,
527 	.go_drop_th = gfs2_glock_drop_th,
528 	.go_type = LM_TYPE_META,
529 };
530 
531 const struct gfs2_glock_operations gfs2_inode_glops = {
532 	.go_xmote_th = inode_go_xmote_th,
533 	.go_xmote_bh = inode_go_xmote_bh,
534 	.go_drop_th = inode_go_drop_th,
535 	.go_sync = inode_go_sync,
536 	.go_inval = inode_go_inval,
537 	.go_demote_ok = inode_go_demote_ok,
538 	.go_lock = inode_go_lock,
539 	.go_unlock = inode_go_unlock,
540 	.go_greedy = inode_greedy,
541 	.go_type = LM_TYPE_INODE,
542 };
543 
544 const struct gfs2_glock_operations gfs2_rgrp_glops = {
545 	.go_xmote_th = gfs2_glock_xmote_th,
546 	.go_drop_th = gfs2_glock_drop_th,
547 	.go_sync = meta_go_sync,
548 	.go_inval = meta_go_inval,
549 	.go_demote_ok = rgrp_go_demote_ok,
550 	.go_lock = rgrp_go_lock,
551 	.go_unlock = rgrp_go_unlock,
552 	.go_type = LM_TYPE_RGRP,
553 };
554 
555 const struct gfs2_glock_operations gfs2_trans_glops = {
556 	.go_xmote_th = trans_go_xmote_th,
557 	.go_xmote_bh = trans_go_xmote_bh,
558 	.go_drop_th = trans_go_drop_th,
559 	.go_type = LM_TYPE_NONDISK,
560 };
561 
562 const struct gfs2_glock_operations gfs2_iopen_glops = {
563 	.go_xmote_th = gfs2_glock_xmote_th,
564 	.go_drop_th = gfs2_glock_drop_th,
565 	.go_type = LM_TYPE_IOPEN,
566 };
567 
568 const struct gfs2_glock_operations gfs2_flock_glops = {
569 	.go_xmote_th = gfs2_glock_xmote_th,
570 	.go_drop_th = gfs2_glock_drop_th,
571 	.go_type = LM_TYPE_FLOCK,
572 };
573 
574 const struct gfs2_glock_operations gfs2_nondisk_glops = {
575 	.go_xmote_th = gfs2_glock_xmote_th,
576 	.go_drop_th = gfs2_glock_drop_th,
577 	.go_type = LM_TYPE_NONDISK,
578 };
579 
580 const struct gfs2_glock_operations gfs2_quota_glops = {
581 	.go_xmote_th = gfs2_glock_xmote_th,
582 	.go_drop_th = gfs2_glock_drop_th,
583 	.go_demote_ok = quota_go_demote_ok,
584 	.go_type = LM_TYPE_QUOTA,
585 };
586 
587 const struct gfs2_glock_operations gfs2_journal_glops = {
588 	.go_xmote_th = gfs2_glock_xmote_th,
589 	.go_drop_th = gfs2_glock_drop_th,
590 	.go_type = LM_TYPE_JOURNAL,
591 };
592 
593