xref: /openbmc/linux/fs/ocfs2/slot_map.c (revision 82df5b73) 
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* -*- mode: c; c-basic-offset: 8; -*-
3  * vim: noexpandtab sw=8 ts=8 sts=0:
4  *
5  * slot_map.c
6  *
7  * Copyright (C) 2002, 2004 Oracle.  All rights reserved.
8  */
9 
10 #include <linux/types.h>
11 #include <linux/slab.h>
12 #include <linux/highmem.h>
13 
14 #include <cluster/masklog.h>
15 
16 #include "ocfs2.h"
17 
18 #include "dlmglue.h"
19 #include "extent_map.h"
20 #include "heartbeat.h"
21 #include "inode.h"
22 #include "slot_map.h"
23 #include "super.h"
24 #include "sysfile.h"
25 #include "ocfs2_trace.h"
26 
27 #include "buffer_head_io.h"
28 
29 
30 struct ocfs2_slot {
31 	int sl_valid;
32 	unsigned int sl_node_num;
33 };
34 
35 struct ocfs2_slot_info {
36 	int si_extended;
37 	int si_slots_per_block;
38 	struct inode *si_inode;
39 	unsigned int si_blocks;
40 	struct buffer_head **si_bh;
41 	unsigned int si_num_slots;
42 	struct ocfs2_slot si_slots[];
43 };
44 
45 
46 static int __ocfs2_node_num_to_slot(struct ocfs2_slot_info *si,
47 				    unsigned int node_num);
48 
49 static void ocfs2_invalidate_slot(struct ocfs2_slot_info *si,
50 				  int slot_num)
51 {
52 	BUG_ON((slot_num < 0) || (slot_num >= si->si_num_slots));
53 	si->si_slots[slot_num].sl_valid = 0;
54 }
55 
56 static void ocfs2_set_slot(struct ocfs2_slot_info *si,
57 			   int slot_num, unsigned int node_num)
58 {
59 	BUG_ON((slot_num < 0) || (slot_num >= si->si_num_slots));
60 
61 	si->si_slots[slot_num].sl_valid = 1;
62 	si->si_slots[slot_num].sl_node_num = node_num;
63 }
64 
65 /* This version is for the extended slot map */
66 static void ocfs2_update_slot_info_extended(struct ocfs2_slot_info *si)
67 {
68 	int b, i, slotno;
69 	struct ocfs2_slot_map_extended *se;
70 
71 	slotno = 0;
72 	for (b = 0; b < si->si_blocks; b++) {
73 		se = (struct ocfs2_slot_map_extended *)si->si_bh[b]->b_data;
74 		for (i = 0;
75 		     (i < si->si_slots_per_block) &&
76 		     (slotno < si->si_num_slots);
77 		     i++, slotno++) {
78 			if (se->se_slots[i].es_valid)
79 				ocfs2_set_slot(si, slotno,
80 					       le32_to_cpu(se->se_slots[i].es_node_num));
81 			else
82 				ocfs2_invalidate_slot(si, slotno);
83 		}
84 	}
85 }
86 
87 /*
88  * Post the slot information on disk into our slot_info struct.
89  * Must be protected by osb_lock.
90  */
91 static void ocfs2_update_slot_info_old(struct ocfs2_slot_info *si)
92 {
93 	int i;
94 	struct ocfs2_slot_map *sm;
95 
96 	sm = (struct ocfs2_slot_map *)si->si_bh[0]->b_data;
97 
98 	for (i = 0; i < si->si_num_slots; i++) {
99 		if (le16_to_cpu(sm->sm_slots[i]) == (u16)OCFS2_INVALID_SLOT)
100 			ocfs2_invalidate_slot(si, i);
101 		else
102 			ocfs2_set_slot(si, i, le16_to_cpu(sm->sm_slots[i]));
103 	}
104 }
105 
106 static void ocfs2_update_slot_info(struct ocfs2_slot_info *si)
107 {
108 	/*
109 	 * The slot data will have been refreshed when ocfs2_super_lock
110 	 * was taken.
111 	 */
112 	if (si->si_extended)
113 		ocfs2_update_slot_info_extended(si);
114 	else
115 		ocfs2_update_slot_info_old(si);
116 }
117 
118 int ocfs2_refresh_slot_info(struct ocfs2_super *osb)
119 {
120 	int ret;
121 	struct ocfs2_slot_info *si = osb->slot_info;
122 
123 	if (si == NULL)
124 		return 0;
125 
126 	BUG_ON(si->si_blocks == 0);
127 	BUG_ON(si->si_bh == NULL);
128 
129 	trace_ocfs2_refresh_slot_info(si->si_blocks);
130 
131 	/*
132 	 * We pass -1 as blocknr because we expect all of si->si_bh to
133 	 * be !NULL.  Thus, ocfs2_read_blocks() will ignore blocknr.  If
134 	 * this is not true, the read of -1 (UINT64_MAX) will fail.
135 	 */
136 	ret = ocfs2_read_blocks(INODE_CACHE(si->si_inode), -1, si->si_blocks,
137 				si->si_bh, OCFS2_BH_IGNORE_CACHE, NULL);
138 	if (ret == 0) {
139 		spin_lock(&osb->osb_lock);
140 		ocfs2_update_slot_info(si);
141 		spin_unlock(&osb->osb_lock);
142 	}
143 
144 	return ret;
145 }
146 
147 /* post the our slot info stuff into it's destination bh and write it
148  * out. */
149 static void ocfs2_update_disk_slot_extended(struct ocfs2_slot_info *si,
150 					    int slot_num,
151 					    struct buffer_head **bh)
152 {
153 	int blkind = slot_num / si->si_slots_per_block;
154 	int slotno = slot_num % si->si_slots_per_block;
155 	struct ocfs2_slot_map_extended *se;
156 
157 	BUG_ON(blkind >= si->si_blocks);
158 
159 	se = (struct ocfs2_slot_map_extended *)si->si_bh[blkind]->b_data;
160 	se->se_slots[slotno].es_valid = si->si_slots[slot_num].sl_valid;
161 	if (si->si_slots[slot_num].sl_valid)
162 		se->se_slots[slotno].es_node_num =
163 			cpu_to_le32(si->si_slots[slot_num].sl_node_num);
164 	*bh = si->si_bh[blkind];
165 }
166 
167 static void ocfs2_update_disk_slot_old(struct ocfs2_slot_info *si,
168 				       int slot_num,
169 				       struct buffer_head **bh)
170 {
171 	int i;
172 	struct ocfs2_slot_map *sm;
173 
174 	sm = (struct ocfs2_slot_map *)si->si_bh[0]->b_data;
175 	for (i = 0; i < si->si_num_slots; i++) {
176 		if (si->si_slots[i].sl_valid)
177 			sm->sm_slots[i] =
178 				cpu_to_le16(si->si_slots[i].sl_node_num);
179 		else
180 			sm->sm_slots[i] = cpu_to_le16(OCFS2_INVALID_SLOT);
181 	}
182 	*bh = si->si_bh[0];
183 }
184 
185 static int ocfs2_update_disk_slot(struct ocfs2_super *osb,
186 				  struct ocfs2_slot_info *si,
187 				  int slot_num)
188 {
189 	int status;
190 	struct buffer_head *bh;
191 
192 	spin_lock(&osb->osb_lock);
193 	if (si->si_extended)
194 		ocfs2_update_disk_slot_extended(si, slot_num, &bh);
195 	else
196 		ocfs2_update_disk_slot_old(si, slot_num, &bh);
197 	spin_unlock(&osb->osb_lock);
198 
199 	status = ocfs2_write_block(osb, bh, INODE_CACHE(si->si_inode));
200 	if (status < 0)
201 		mlog_errno(status);
202 
203 	return status;
204 }
205 
206 /*
207  * Calculate how many bytes are needed by the slot map.  Returns
208  * an error if the slot map file is too small.
209  */
210 static int ocfs2_slot_map_physical_size(struct ocfs2_super *osb,
211 					struct inode *inode,
212 					unsigned long long *bytes)
213 {
214 	unsigned long long bytes_needed;
215 
216 	if (ocfs2_uses_extended_slot_map(osb)) {
217 		bytes_needed = osb->max_slots *
218 			sizeof(struct ocfs2_extended_slot);
219 	} else {
220 		bytes_needed = osb->max_slots * sizeof(__le16);
221 	}
222 	if (bytes_needed > i_size_read(inode)) {
223 		mlog(ML_ERROR,
224 		     "Slot map file is too small!  (size %llu, needed %llu)\n",
225 		     i_size_read(inode), bytes_needed);
226 		return -ENOSPC;
227 	}
228 
229 	*bytes = bytes_needed;
230 	return 0;
231 }
232 
233 /* try to find global node in the slot info. Returns -ENOENT
234  * if nothing is found. */
235 static int __ocfs2_node_num_to_slot(struct ocfs2_slot_info *si,
236 				    unsigned int node_num)
237 {
238 	int i, ret = -ENOENT;
239 
240 	for(i = 0; i < si->si_num_slots; i++) {
241 		if (si->si_slots[i].sl_valid &&
242 		    (node_num == si->si_slots[i].sl_node_num)) {
243 			ret = i;
244 			break;
245 		}
246 	}
247 
248 	return ret;
249 }
250 
251 static int __ocfs2_find_empty_slot(struct ocfs2_slot_info *si,
252 				   int preferred)
253 {
254 	int i, ret = -ENOSPC;
255 
256 	if ((preferred >= 0) && (preferred < si->si_num_slots)) {
257 		if (!si->si_slots[preferred].sl_valid ||
258 		    !si->si_slots[preferred].sl_node_num) {
259 			ret = preferred;
260 			goto out;
261 		}
262 	}
263 
264 	for(i = 0; i < si->si_num_slots; i++) {
265 		if (!si->si_slots[i].sl_valid ||
266 		    !si->si_slots[i].sl_node_num) {
267 			ret = i;
268 			break;
269 		}
270 	}
271 out:
272 	return ret;
273 }
274 
275 int ocfs2_node_num_to_slot(struct ocfs2_super *osb, unsigned int node_num)
276 {
277 	int slot;
278 	struct ocfs2_slot_info *si = osb->slot_info;
279 
280 	spin_lock(&osb->osb_lock);
281 	slot = __ocfs2_node_num_to_slot(si, node_num);
282 	spin_unlock(&osb->osb_lock);
283 
284 	return slot;
285 }
286 
287 int ocfs2_slot_to_node_num_locked(struct ocfs2_super *osb, int slot_num,
288 				  unsigned int *node_num)
289 {
290 	struct ocfs2_slot_info *si = osb->slot_info;
291 
292 	assert_spin_locked(&osb->osb_lock);
293 
294 	BUG_ON(slot_num < 0);
295 	BUG_ON(slot_num >= osb->max_slots);
296 
297 	if (!si->si_slots[slot_num].sl_valid)
298 		return -ENOENT;
299 
300 	*node_num = si->si_slots[slot_num].sl_node_num;
301 	return 0;
302 }
303 
304 static void __ocfs2_free_slot_info(struct ocfs2_slot_info *si)
305 {
306 	unsigned int i;
307 
308 	if (si == NULL)
309 		return;
310 
311 	iput(si->si_inode);
312 	if (si->si_bh) {
313 		for (i = 0; i < si->si_blocks; i++) {
314 			if (si->si_bh[i]) {
315 				brelse(si->si_bh[i]);
316 				si->si_bh[i] = NULL;
317 			}
318 		}
319 		kfree(si->si_bh);
320 	}
321 
322 	kfree(si);
323 }
324 
325 int ocfs2_clear_slot(struct ocfs2_super *osb, int slot_num)
326 {
327 	struct ocfs2_slot_info *si = osb->slot_info;
328 
329 	if (si == NULL)
330 		return 0;
331 
332 	spin_lock(&osb->osb_lock);
333 	ocfs2_invalidate_slot(si, slot_num);
334 	spin_unlock(&osb->osb_lock);
335 
336 	return ocfs2_update_disk_slot(osb, osb->slot_info, slot_num);
337 }
338 
339 static int ocfs2_map_slot_buffers(struct ocfs2_super *osb,
340 				  struct ocfs2_slot_info *si)
341 {
342 	int status = 0;
343 	u64 blkno;
344 	unsigned long long blocks, bytes = 0;
345 	unsigned int i;
346 	struct buffer_head *bh;
347 
348 	status = ocfs2_slot_map_physical_size(osb, si->si_inode, &bytes);
349 	if (status)
350 		goto bail;
351 
352 	blocks = ocfs2_blocks_for_bytes(si->si_inode->i_sb, bytes);
353 	BUG_ON(blocks > UINT_MAX);
354 	si->si_blocks = blocks;
355 	if (!si->si_blocks)
356 		goto bail;
357 
358 	if (si->si_extended)
359 		si->si_slots_per_block =
360 			(osb->sb->s_blocksize /
361 			 sizeof(struct ocfs2_extended_slot));
362 	else
363 		si->si_slots_per_block = osb->sb->s_blocksize / sizeof(__le16);
364 
365 	/* The size checks above should ensure this */
366 	BUG_ON((osb->max_slots / si->si_slots_per_block) > blocks);
367 
368 	trace_ocfs2_map_slot_buffers(bytes, si->si_blocks);
369 
370 	si->si_bh = kcalloc(si->si_blocks, sizeof(struct buffer_head *),
371 			    GFP_KERNEL);
372 	if (!si->si_bh) {
373 		status = -ENOMEM;
374 		mlog_errno(status);
375 		goto bail;
376 	}
377 
378 	for (i = 0; i < si->si_blocks; i++) {
379 		status = ocfs2_extent_map_get_blocks(si->si_inode, i,
380 						     &blkno, NULL, NULL);
381 		if (status < 0) {
382 			mlog_errno(status);
383 			goto bail;
384 		}
385 
386 		trace_ocfs2_map_slot_buffers_block((unsigned long long)blkno, i);
387 
388 		bh = NULL;  /* Acquire a fresh bh */
389 		status = ocfs2_read_blocks(INODE_CACHE(si->si_inode), blkno,
390 					   1, &bh, OCFS2_BH_IGNORE_CACHE, NULL);
391 		if (status < 0) {
392 			mlog_errno(status);
393 			goto bail;
394 		}
395 
396 		si->si_bh[i] = bh;
397 	}
398 
399 bail:
400 	return status;
401 }
402 
403 int ocfs2_init_slot_info(struct ocfs2_super *osb)
404 {
405 	int status;
406 	struct inode *inode = NULL;
407 	struct ocfs2_slot_info *si;
408 
409 	si = kzalloc(struct_size(si, si_slots, osb->max_slots), GFP_KERNEL);
410 	if (!si) {
411 		status = -ENOMEM;
412 		mlog_errno(status);
413 		return status;
414 	}
415 
416 	si->si_extended = ocfs2_uses_extended_slot_map(osb);
417 	si->si_num_slots = osb->max_slots;
418 
419 	inode = ocfs2_get_system_file_inode(osb, SLOT_MAP_SYSTEM_INODE,
420 					    OCFS2_INVALID_SLOT);
421 	if (!inode) {
422 		status = -EINVAL;
423 		mlog_errno(status);
424 		goto bail;
425 	}
426 
427 	si->si_inode = inode;
428 	status = ocfs2_map_slot_buffers(osb, si);
429 	if (status < 0) {
430 		mlog_errno(status);
431 		goto bail;
432 	}
433 
434 	osb->slot_info = (struct ocfs2_slot_info *)si;
435 bail:
436 	if (status < 0)
437 		__ocfs2_free_slot_info(si);
438 
439 	return status;
440 }
441 
442 void ocfs2_free_slot_info(struct ocfs2_super *osb)
443 {
444 	struct ocfs2_slot_info *si = osb->slot_info;
445 
446 	osb->slot_info = NULL;
447 	__ocfs2_free_slot_info(si);
448 }
449 
450 int ocfs2_find_slot(struct ocfs2_super *osb)
451 {
452 	int status;
453 	int slot;
454 	struct ocfs2_slot_info *si;
455 
456 	si = osb->slot_info;
457 
458 	spin_lock(&osb->osb_lock);
459 	ocfs2_update_slot_info(si);
460 
461 	if (ocfs2_mount_local(osb))
462 		/* use slot 0 directly in local mode */
463 		slot = 0;
464 	else {
465 		/* search for ourselves first and take the slot if it already
466 		 * exists. Perhaps we need to mark this in a variable for our
467 		 * own journal recovery? Possibly not, though we certainly
468 		 * need to warn to the user */
469 		slot = __ocfs2_node_num_to_slot(si, osb->node_num);
470 		if (slot < 0) {
471 			/* if no slot yet, then just take 1st available
472 			 * one. */
473 			slot = __ocfs2_find_empty_slot(si, osb->preferred_slot);
474 			if (slot < 0) {
475 				spin_unlock(&osb->osb_lock);
476 				mlog(ML_ERROR, "no free slots available!\n");
477 				status = -EINVAL;
478 				goto bail;
479 			}
480 		} else
481 			printk(KERN_INFO "ocfs2: Slot %d on device (%s) was "
482 			       "already allocated to this node!\n",
483 			       slot, osb->dev_str);
484 	}
485 
486 	ocfs2_set_slot(si, slot, osb->node_num);
487 	osb->slot_num = slot;
488 	spin_unlock(&osb->osb_lock);
489 
490 	trace_ocfs2_find_slot(osb->slot_num);
491 
492 	status = ocfs2_update_disk_slot(osb, si, osb->slot_num);
493 	if (status < 0) {
494 		mlog_errno(status);
495 		/*
496 		 * if write block failed, invalidate slot to avoid overwrite
497 		 * slot during dismount in case another node rightly has mounted
498 		 */
499 		spin_lock(&osb->osb_lock);
500 		ocfs2_invalidate_slot(si, osb->slot_num);
501 		osb->slot_num = OCFS2_INVALID_SLOT;
502 		spin_unlock(&osb->osb_lock);
503 	}
504 
505 bail:
506 	return status;
507 }
508 
509 void ocfs2_put_slot(struct ocfs2_super *osb)
510 {
511 	int status, slot_num;
512 	struct ocfs2_slot_info *si = osb->slot_info;
513 
514 	if (!si)
515 		return;
516 
517 	spin_lock(&osb->osb_lock);
518 	ocfs2_update_slot_info(si);
519 
520 	slot_num = osb->slot_num;
521 	ocfs2_invalidate_slot(si, osb->slot_num);
522 	osb->slot_num = OCFS2_INVALID_SLOT;
523 	spin_unlock(&osb->osb_lock);
524 
525 	status = ocfs2_update_disk_slot(osb, si, slot_num);
526 	if (status < 0)
527 		mlog_errno(status);
528 
529 	ocfs2_free_slot_info(osb);
530 }
531