ACPI: thinkpad-acpi: clean up hotkey_notify()
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / fs / ocfs2 / slot_map.c
blobbdda2d8f85080a5a883c1b01b4cc1fbe68d83d18
1 /* -*- mode: c; c-basic-offset: 8; -*-
2 * vim: noexpandtab sw=8 ts=8 sts=0:
4 * slot_map.c
8 * Copyright (C) 2002, 2004 Oracle. All rights reserved.
10 * This program is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU General Public
12 * License as published by the Free Software Foundation; either
13 * version 2 of the License, or (at your option) any later version.
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18 * General Public License for more details.
20 * You should have received a copy of the GNU General Public
21 * License along with this program; if not, write to the
22 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
23 * Boston, MA 021110-1307, USA.
26 #include <linux/types.h>
27 #include <linux/slab.h>
28 #include <linux/highmem.h>
30 #define MLOG_MASK_PREFIX ML_SUPER
31 #include <cluster/masklog.h>
33 #include "ocfs2.h"
35 #include "dlmglue.h"
36 #include "extent_map.h"
37 #include "heartbeat.h"
38 #include "inode.h"
39 #include "slot_map.h"
40 #include "super.h"
41 #include "sysfile.h"
43 #include "buffer_head_io.h"
46 struct ocfs2_slot {
47 int sl_valid;
48 unsigned int sl_node_num;
51 struct ocfs2_slot_info {
52 int si_extended;
53 int si_slots_per_block;
54 struct inode *si_inode;
55 unsigned int si_blocks;
56 struct buffer_head **si_bh;
57 unsigned int si_num_slots;
58 struct ocfs2_slot *si_slots;
62 static int __ocfs2_node_num_to_slot(struct ocfs2_slot_info *si,
63 unsigned int node_num);
65 static void ocfs2_invalidate_slot(struct ocfs2_slot_info *si,
66 int slot_num)
68 BUG_ON((slot_num < 0) || (slot_num >= si->si_num_slots));
69 si->si_slots[slot_num].sl_valid = 0;
72 static void ocfs2_set_slot(struct ocfs2_slot_info *si,
73 int slot_num, unsigned int node_num)
75 BUG_ON((slot_num < 0) || (slot_num >= si->si_num_slots));
77 si->si_slots[slot_num].sl_valid = 1;
78 si->si_slots[slot_num].sl_node_num = node_num;
81 /* This version is for the extended slot map */
82 static void ocfs2_update_slot_info_extended(struct ocfs2_slot_info *si)
84 int b, i, slotno;
85 struct ocfs2_slot_map_extended *se;
87 slotno = 0;
88 for (b = 0; b < si->si_blocks; b++) {
89 se = (struct ocfs2_slot_map_extended *)si->si_bh[b]->b_data;
90 for (i = 0;
91 (i < si->si_slots_per_block) &&
92 (slotno < si->si_num_slots);
93 i++, slotno++) {
94 if (se->se_slots[i].es_valid)
95 ocfs2_set_slot(si, slotno,
96 le32_to_cpu(se->se_slots[i].es_node_num));
97 else
98 ocfs2_invalidate_slot(si, slotno);
104 * Post the slot information on disk into our slot_info struct.
105 * Must be protected by osb_lock.
107 static void ocfs2_update_slot_info_old(struct ocfs2_slot_info *si)
109 int i;
110 struct ocfs2_slot_map *sm;
112 sm = (struct ocfs2_slot_map *)si->si_bh[0]->b_data;
114 for (i = 0; i < si->si_num_slots; i++) {
115 if (le16_to_cpu(sm->sm_slots[i]) == (u16)OCFS2_INVALID_SLOT)
116 ocfs2_invalidate_slot(si, i);
117 else
118 ocfs2_set_slot(si, i, le16_to_cpu(sm->sm_slots[i]));
122 static void ocfs2_update_slot_info(struct ocfs2_slot_info *si)
125 * The slot data will have been refreshed when ocfs2_super_lock
126 * was taken.
128 if (si->si_extended)
129 ocfs2_update_slot_info_extended(si);
130 else
131 ocfs2_update_slot_info_old(si);
134 int ocfs2_refresh_slot_info(struct ocfs2_super *osb)
136 int ret;
137 struct ocfs2_slot_info *si = osb->slot_info;
139 if (si == NULL)
140 return 0;
142 BUG_ON(si->si_blocks == 0);
143 BUG_ON(si->si_bh == NULL);
145 mlog(0, "Refreshing slot map, reading %u block(s)\n",
146 si->si_blocks);
149 * We pass -1 as blocknr because we expect all of si->si_bh to
150 * be !NULL. Thus, ocfs2_read_blocks() will ignore blocknr. If
151 * this is not true, the read of -1 (UINT64_MAX) will fail.
153 ret = ocfs2_read_blocks(si->si_inode, -1, si->si_blocks, si->si_bh,
154 OCFS2_BH_IGNORE_CACHE);
155 if (ret == 0) {
156 spin_lock(&osb->osb_lock);
157 ocfs2_update_slot_info(si);
158 spin_unlock(&osb->osb_lock);
161 return ret;
164 /* post the our slot info stuff into it's destination bh and write it
165 * out. */
166 static void ocfs2_update_disk_slot_extended(struct ocfs2_slot_info *si,
167 int slot_num,
168 struct buffer_head **bh)
170 int blkind = slot_num / si->si_slots_per_block;
171 int slotno = slot_num % si->si_slots_per_block;
172 struct ocfs2_slot_map_extended *se;
174 BUG_ON(blkind >= si->si_blocks);
176 se = (struct ocfs2_slot_map_extended *)si->si_bh[blkind]->b_data;
177 se->se_slots[slotno].es_valid = si->si_slots[slot_num].sl_valid;
178 if (si->si_slots[slot_num].sl_valid)
179 se->se_slots[slotno].es_node_num =
180 cpu_to_le32(si->si_slots[slot_num].sl_node_num);
181 *bh = si->si_bh[blkind];
184 static void ocfs2_update_disk_slot_old(struct ocfs2_slot_info *si,
185 int slot_num,
186 struct buffer_head **bh)
188 int i;
189 struct ocfs2_slot_map *sm;
191 sm = (struct ocfs2_slot_map *)si->si_bh[0]->b_data;
192 for (i = 0; i < si->si_num_slots; i++) {
193 if (si->si_slots[i].sl_valid)
194 sm->sm_slots[i] =
195 cpu_to_le16(si->si_slots[i].sl_node_num);
196 else
197 sm->sm_slots[i] = cpu_to_le16(OCFS2_INVALID_SLOT);
199 *bh = si->si_bh[0];
202 static int ocfs2_update_disk_slot(struct ocfs2_super *osb,
203 struct ocfs2_slot_info *si,
204 int slot_num)
206 int status;
207 struct buffer_head *bh;
209 spin_lock(&osb->osb_lock);
210 if (si->si_extended)
211 ocfs2_update_disk_slot_extended(si, slot_num, &bh);
212 else
213 ocfs2_update_disk_slot_old(si, slot_num, &bh);
214 spin_unlock(&osb->osb_lock);
216 status = ocfs2_write_block(osb, bh, si->si_inode);
217 if (status < 0)
218 mlog_errno(status);
220 return status;
224 * Calculate how many bytes are needed by the slot map. Returns
225 * an error if the slot map file is too small.
227 static int ocfs2_slot_map_physical_size(struct ocfs2_super *osb,
228 struct inode *inode,
229 unsigned long long *bytes)
231 unsigned long long bytes_needed;
233 if (ocfs2_uses_extended_slot_map(osb)) {
234 bytes_needed = osb->max_slots *
235 sizeof(struct ocfs2_extended_slot);
236 } else {
237 bytes_needed = osb->max_slots * sizeof(__le16);
239 if (bytes_needed > i_size_read(inode)) {
240 mlog(ML_ERROR,
241 "Slot map file is too small! (size %llu, needed %llu)\n",
242 i_size_read(inode), bytes_needed);
243 return -ENOSPC;
246 *bytes = bytes_needed;
247 return 0;
250 /* try to find global node in the slot info. Returns -ENOENT
251 * if nothing is found. */
252 static int __ocfs2_node_num_to_slot(struct ocfs2_slot_info *si,
253 unsigned int node_num)
255 int i, ret = -ENOENT;
257 for(i = 0; i < si->si_num_slots; i++) {
258 if (si->si_slots[i].sl_valid &&
259 (node_num == si->si_slots[i].sl_node_num)) {
260 ret = i;
261 break;
265 return ret;
268 static int __ocfs2_find_empty_slot(struct ocfs2_slot_info *si,
269 int preferred)
271 int i, ret = -ENOSPC;
273 if ((preferred >= 0) && (preferred < si->si_num_slots)) {
274 if (!si->si_slots[preferred].sl_valid) {
275 ret = preferred;
276 goto out;
280 for(i = 0; i < si->si_num_slots; i++) {
281 if (!si->si_slots[i].sl_valid) {
282 ret = i;
283 break;
286 out:
287 return ret;
290 int ocfs2_node_num_to_slot(struct ocfs2_super *osb, unsigned int node_num)
292 int slot;
293 struct ocfs2_slot_info *si = osb->slot_info;
295 spin_lock(&osb->osb_lock);
296 slot = __ocfs2_node_num_to_slot(si, node_num);
297 spin_unlock(&osb->osb_lock);
299 return slot;
302 int ocfs2_slot_to_node_num_locked(struct ocfs2_super *osb, int slot_num,
303 unsigned int *node_num)
305 struct ocfs2_slot_info *si = osb->slot_info;
307 assert_spin_locked(&osb->osb_lock);
309 BUG_ON(slot_num < 0);
310 BUG_ON(slot_num > osb->max_slots);
312 if (!si->si_slots[slot_num].sl_valid)
313 return -ENOENT;
315 *node_num = si->si_slots[slot_num].sl_node_num;
316 return 0;
319 static void __ocfs2_free_slot_info(struct ocfs2_slot_info *si)
321 unsigned int i;
323 if (si == NULL)
324 return;
326 if (si->si_inode)
327 iput(si->si_inode);
328 if (si->si_bh) {
329 for (i = 0; i < si->si_blocks; i++) {
330 if (si->si_bh[i]) {
331 brelse(si->si_bh[i]);
332 si->si_bh[i] = NULL;
335 kfree(si->si_bh);
338 kfree(si);
341 int ocfs2_clear_slot(struct ocfs2_super *osb, int slot_num)
343 struct ocfs2_slot_info *si = osb->slot_info;
345 if (si == NULL)
346 return 0;
348 spin_lock(&osb->osb_lock);
349 ocfs2_invalidate_slot(si, slot_num);
350 spin_unlock(&osb->osb_lock);
352 return ocfs2_update_disk_slot(osb, osb->slot_info, slot_num);
355 static int ocfs2_map_slot_buffers(struct ocfs2_super *osb,
356 struct ocfs2_slot_info *si)
358 int status = 0;
359 u64 blkno;
360 unsigned long long blocks, bytes;
361 unsigned int i;
362 struct buffer_head *bh;
364 status = ocfs2_slot_map_physical_size(osb, si->si_inode, &bytes);
365 if (status)
366 goto bail;
368 blocks = ocfs2_blocks_for_bytes(si->si_inode->i_sb, bytes);
369 BUG_ON(blocks > UINT_MAX);
370 si->si_blocks = blocks;
371 if (!si->si_blocks)
372 goto bail;
374 if (si->si_extended)
375 si->si_slots_per_block =
376 (osb->sb->s_blocksize /
377 sizeof(struct ocfs2_extended_slot));
378 else
379 si->si_slots_per_block = osb->sb->s_blocksize / sizeof(__le16);
381 /* The size checks above should ensure this */
382 BUG_ON((osb->max_slots / si->si_slots_per_block) > blocks);
384 mlog(0, "Slot map needs %u buffers for %llu bytes\n",
385 si->si_blocks, bytes);
387 si->si_bh = kzalloc(sizeof(struct buffer_head *) * si->si_blocks,
388 GFP_KERNEL);
389 if (!si->si_bh) {
390 status = -ENOMEM;
391 mlog_errno(status);
392 goto bail;
395 for (i = 0; i < si->si_blocks; i++) {
396 status = ocfs2_extent_map_get_blocks(si->si_inode, i,
397 &blkno, NULL, NULL);
398 if (status < 0) {
399 mlog_errno(status);
400 goto bail;
403 mlog(0, "Reading slot map block %u at %llu\n", i,
404 (unsigned long long)blkno);
406 bh = NULL; /* Acquire a fresh bh */
407 status = ocfs2_read_blocks(si->si_inode, blkno, 1, &bh,
408 OCFS2_BH_IGNORE_CACHE);
409 if (status < 0) {
410 mlog_errno(status);
411 goto bail;
414 si->si_bh[i] = bh;
417 bail:
418 return status;
421 int ocfs2_init_slot_info(struct ocfs2_super *osb)
423 int status;
424 struct inode *inode = NULL;
425 struct ocfs2_slot_info *si;
427 si = kzalloc(sizeof(struct ocfs2_slot_info) +
428 (sizeof(struct ocfs2_slot) * osb->max_slots),
429 GFP_KERNEL);
430 if (!si) {
431 status = -ENOMEM;
432 mlog_errno(status);
433 goto bail;
436 si->si_extended = ocfs2_uses_extended_slot_map(osb);
437 si->si_num_slots = osb->max_slots;
438 si->si_slots = (struct ocfs2_slot *)((char *)si +
439 sizeof(struct ocfs2_slot_info));
441 inode = ocfs2_get_system_file_inode(osb, SLOT_MAP_SYSTEM_INODE,
442 OCFS2_INVALID_SLOT);
443 if (!inode) {
444 status = -EINVAL;
445 mlog_errno(status);
446 goto bail;
449 si->si_inode = inode;
450 status = ocfs2_map_slot_buffers(osb, si);
451 if (status < 0) {
452 mlog_errno(status);
453 goto bail;
456 osb->slot_info = (struct ocfs2_slot_info *)si;
457 bail:
458 if (status < 0 && si)
459 __ocfs2_free_slot_info(si);
461 return status;
464 void ocfs2_free_slot_info(struct ocfs2_super *osb)
466 struct ocfs2_slot_info *si = osb->slot_info;
468 osb->slot_info = NULL;
469 __ocfs2_free_slot_info(si);
472 int ocfs2_find_slot(struct ocfs2_super *osb)
474 int status;
475 int slot;
476 struct ocfs2_slot_info *si;
478 mlog_entry_void();
480 si = osb->slot_info;
482 spin_lock(&osb->osb_lock);
483 ocfs2_update_slot_info(si);
485 /* search for ourselves first and take the slot if it already
486 * exists. Perhaps we need to mark this in a variable for our
487 * own journal recovery? Possibly not, though we certainly
488 * need to warn to the user */
489 slot = __ocfs2_node_num_to_slot(si, osb->node_num);
490 if (slot < 0) {
491 /* if no slot yet, then just take 1st available
492 * one. */
493 slot = __ocfs2_find_empty_slot(si, osb->preferred_slot);
494 if (slot < 0) {
495 spin_unlock(&osb->osb_lock);
496 mlog(ML_ERROR, "no free slots available!\n");
497 status = -EINVAL;
498 goto bail;
500 } else
501 mlog(ML_NOTICE, "slot %d is already allocated to this node!\n",
502 slot);
504 ocfs2_set_slot(si, slot, osb->node_num);
505 osb->slot_num = slot;
506 spin_unlock(&osb->osb_lock);
508 mlog(0, "taking node slot %d\n", osb->slot_num);
510 status = ocfs2_update_disk_slot(osb, si, osb->slot_num);
511 if (status < 0)
512 mlog_errno(status);
514 bail:
515 mlog_exit(status);
516 return status;
519 void ocfs2_put_slot(struct ocfs2_super *osb)
521 int status, slot_num;
522 struct ocfs2_slot_info *si = osb->slot_info;
524 if (!si)
525 return;
527 spin_lock(&osb->osb_lock);
528 ocfs2_update_slot_info(si);
530 slot_num = osb->slot_num;
531 ocfs2_invalidate_slot(si, osb->slot_num);
532 osb->slot_num = OCFS2_INVALID_SLOT;
533 spin_unlock(&osb->osb_lock);
535 status = ocfs2_update_disk_slot(osb, si, slot_num);
536 if (status < 0) {
537 mlog_errno(status);
538 goto bail;
541 bail:
542 ocfs2_free_slot_info(osb);