1 /* -*- mode: c; c-basic-offset: 8; -*- 2 * vim: noexpandtab sw=8 ts=8 sts=0: 3 * 4 * slot_map.c 5 * 6 * 7 * 8 * Copyright (C) 2002, 2004 Oracle. All rights reserved. 9 * 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. 14 * 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. 19 * 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. 24 */ 25 26 #include <linux/types.h> 27 #include <linux/slab.h> 28 #include <linux/highmem.h> 29 30 #include <cluster/masklog.h> 31 32 #include "ocfs2.h" 33 34 #include "dlmglue.h" 35 #include "extent_map.h" 36 #include "heartbeat.h" 37 #include "inode.h" 38 #include "slot_map.h" 39 #include "super.h" 40 #include "sysfile.h" 41 #include "ocfs2_trace.h" 42 43 #include "buffer_head_io.h" 44 45 46 struct ocfs2_slot { 47 int sl_valid; 48 unsigned int sl_node_num; 49 }; 50 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; 59 }; 60 61 62 static int __ocfs2_node_num_to_slot(struct ocfs2_slot_info *si, 63 unsigned int node_num); 64 65 static void ocfs2_invalidate_slot(struct ocfs2_slot_info *si, 66 int slot_num) 67 { 68 BUG_ON((slot_num < 0) || (slot_num >= si->si_num_slots)); 69 si->si_slots[slot_num].sl_valid = 0; 70 } 71 72 static void ocfs2_set_slot(struct ocfs2_slot_info *si, 73 int slot_num, unsigned int node_num) 74 { 75 BUG_ON((slot_num < 0) || (slot_num >= si->si_num_slots)); 76 77 si->si_slots[slot_num].sl_valid = 1; 78 si->si_slots[slot_num].sl_node_num = node_num; 79 } 80 81 /* This version is for the extended slot map */ 82 static void ocfs2_update_slot_info_extended(struct ocfs2_slot_info *si) 83 { 84 int b, i, slotno; 85 struct ocfs2_slot_map_extended *se; 86 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); 99 } 100 } 101 } 102 103 /* 104 * Post the slot information on disk into our slot_info struct. 105 * Must be protected by osb_lock. 106 */ 107 static void ocfs2_update_slot_info_old(struct ocfs2_slot_info *si) 108 { 109 int i; 110 struct ocfs2_slot_map *sm; 111 112 sm = (struct ocfs2_slot_map *)si->si_bh[0]->b_data; 113 114 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])); 119 } 120 } 121 122 static void ocfs2_update_slot_info(struct ocfs2_slot_info *si) 123 { 124 /* 125 * The slot data will have been refreshed when ocfs2_super_lock 126 * was taken. 127 */ 128 if (si->si_extended) 129 ocfs2_update_slot_info_extended(si); 130 else 131 ocfs2_update_slot_info_old(si); 132 } 133 134 int ocfs2_refresh_slot_info(struct ocfs2_super *osb) 135 { 136 int ret; 137 struct ocfs2_slot_info *si = osb->slot_info; 138 139 if (si == NULL) 140 return 0; 141 142 BUG_ON(si->si_blocks == 0); 143 BUG_ON(si->si_bh == NULL); 144 145 trace_ocfs2_refresh_slot_info(si->si_blocks); 146 147 /* 148 * We pass -1 as blocknr because we expect all of si->si_bh to 149 * be !NULL. Thus, ocfs2_read_blocks() will ignore blocknr. If 150 * this is not true, the read of -1 (UINT64_MAX) will fail. 151 */ 152 ret = ocfs2_read_blocks(INODE_CACHE(si->si_inode), -1, si->si_blocks, 153 si->si_bh, OCFS2_BH_IGNORE_CACHE, NULL); 154 if (ret == 0) { 155 spin_lock(&osb->osb_lock); 156 ocfs2_update_slot_info(si); 157 spin_unlock(&osb->osb_lock); 158 } 159 160 return ret; 161 } 162 163 /* post the our slot info stuff into it's destination bh and write it 164 * out. */ 165 static void ocfs2_update_disk_slot_extended(struct ocfs2_slot_info *si, 166 int slot_num, 167 struct buffer_head **bh) 168 { 169 int blkind = slot_num / si->si_slots_per_block; 170 int slotno = slot_num % si->si_slots_per_block; 171 struct ocfs2_slot_map_extended *se; 172 173 BUG_ON(blkind >= si->si_blocks); 174 175 se = (struct ocfs2_slot_map_extended *)si->si_bh[blkind]->b_data; 176 se->se_slots[slotno].es_valid = si->si_slots[slot_num].sl_valid; 177 if (si->si_slots[slot_num].sl_valid) 178 se->se_slots[slotno].es_node_num = 179 cpu_to_le32(si->si_slots[slot_num].sl_node_num); 180 *bh = si->si_bh[blkind]; 181 } 182 183 static void ocfs2_update_disk_slot_old(struct ocfs2_slot_info *si, 184 int slot_num, 185 struct buffer_head **bh) 186 { 187 int i; 188 struct ocfs2_slot_map *sm; 189 190 sm = (struct ocfs2_slot_map *)si->si_bh[0]->b_data; 191 for (i = 0; i < si->si_num_slots; i++) { 192 if (si->si_slots[i].sl_valid) 193 sm->sm_slots[i] = 194 cpu_to_le16(si->si_slots[i].sl_node_num); 195 else 196 sm->sm_slots[i] = cpu_to_le16(OCFS2_INVALID_SLOT); 197 } 198 *bh = si->si_bh[0]; 199 } 200 201 static int ocfs2_update_disk_slot(struct ocfs2_super *osb, 202 struct ocfs2_slot_info *si, 203 int slot_num) 204 { 205 int status; 206 struct buffer_head *bh; 207 208 spin_lock(&osb->osb_lock); 209 if (si->si_extended) 210 ocfs2_update_disk_slot_extended(si, slot_num, &bh); 211 else 212 ocfs2_update_disk_slot_old(si, slot_num, &bh); 213 spin_unlock(&osb->osb_lock); 214 215 status = ocfs2_write_block(osb, bh, INODE_CACHE(si->si_inode)); 216 if (status < 0) 217 mlog_errno(status); 218 219 return status; 220 } 221 222 /* 223 * Calculate how many bytes are needed by the slot map. Returns 224 * an error if the slot map file is too small. 225 */ 226 static int ocfs2_slot_map_physical_size(struct ocfs2_super *osb, 227 struct inode *inode, 228 unsigned long long *bytes) 229 { 230 unsigned long long bytes_needed; 231 232 if (ocfs2_uses_extended_slot_map(osb)) { 233 bytes_needed = osb->max_slots * 234 sizeof(struct ocfs2_extended_slot); 235 } else { 236 bytes_needed = osb->max_slots * sizeof(__le16); 237 } 238 if (bytes_needed > i_size_read(inode)) { 239 mlog(ML_ERROR, 240 "Slot map file is too small! (size %llu, needed %llu)\n", 241 i_size_read(inode), bytes_needed); 242 return -ENOSPC; 243 } 244 245 *bytes = bytes_needed; 246 return 0; 247 } 248 249 /* try to find global node in the slot info. Returns -ENOENT 250 * if nothing is found. */ 251 static int __ocfs2_node_num_to_slot(struct ocfs2_slot_info *si, 252 unsigned int node_num) 253 { 254 int i, ret = -ENOENT; 255 256 for(i = 0; i < si->si_num_slots; i++) { 257 if (si->si_slots[i].sl_valid && 258 (node_num == si->si_slots[i].sl_node_num)) { 259 ret = i; 260 break; 261 } 262 } 263 264 return ret; 265 } 266 267 static int __ocfs2_find_empty_slot(struct ocfs2_slot_info *si, 268 int preferred) 269 { 270 int i, ret = -ENOSPC; 271 272 if ((preferred >= 0) && (preferred < si->si_num_slots)) { 273 if (!si->si_slots[preferred].sl_valid) { 274 ret = preferred; 275 goto out; 276 } 277 } 278 279 for(i = 0; i < si->si_num_slots; i++) { 280 if (!si->si_slots[i].sl_valid) { 281 ret = i; 282 break; 283 } 284 } 285 out: 286 return ret; 287 } 288 289 int ocfs2_node_num_to_slot(struct ocfs2_super *osb, unsigned int node_num) 290 { 291 int slot; 292 struct ocfs2_slot_info *si = osb->slot_info; 293 294 spin_lock(&osb->osb_lock); 295 slot = __ocfs2_node_num_to_slot(si, node_num); 296 spin_unlock(&osb->osb_lock); 297 298 return slot; 299 } 300 301 int ocfs2_slot_to_node_num_locked(struct ocfs2_super *osb, int slot_num, 302 unsigned int *node_num) 303 { 304 struct ocfs2_slot_info *si = osb->slot_info; 305 306 assert_spin_locked(&osb->osb_lock); 307 308 BUG_ON(slot_num < 0); 309 BUG_ON(slot_num > osb->max_slots); 310 311 if (!si->si_slots[slot_num].sl_valid) 312 return -ENOENT; 313 314 *node_num = si->si_slots[slot_num].sl_node_num; 315 return 0; 316 } 317 318 static void __ocfs2_free_slot_info(struct ocfs2_slot_info *si) 319 { 320 unsigned int i; 321 322 if (si == NULL) 323 return; 324 325 if (si->si_inode) 326 iput(si->si_inode); 327 if (si->si_bh) { 328 for (i = 0; i < si->si_blocks; i++) { 329 if (si->si_bh[i]) { 330 brelse(si->si_bh[i]); 331 si->si_bh[i] = NULL; 332 } 333 } 334 kfree(si->si_bh); 335 } 336 337 kfree(si); 338 } 339 340 int ocfs2_clear_slot(struct ocfs2_super *osb, int slot_num) 341 { 342 struct ocfs2_slot_info *si = osb->slot_info; 343 344 if (si == NULL) 345 return 0; 346 347 spin_lock(&osb->osb_lock); 348 ocfs2_invalidate_slot(si, slot_num); 349 spin_unlock(&osb->osb_lock); 350 351 return ocfs2_update_disk_slot(osb, osb->slot_info, slot_num); 352 } 353 354 static int ocfs2_map_slot_buffers(struct ocfs2_super *osb, 355 struct ocfs2_slot_info *si) 356 { 357 int status = 0; 358 u64 blkno; 359 unsigned long long blocks, bytes = 0; 360 unsigned int i; 361 struct buffer_head *bh; 362 363 status = ocfs2_slot_map_physical_size(osb, si->si_inode, &bytes); 364 if (status) 365 goto bail; 366 367 blocks = ocfs2_blocks_for_bytes(si->si_inode->i_sb, bytes); 368 BUG_ON(blocks > UINT_MAX); 369 si->si_blocks = blocks; 370 if (!si->si_blocks) 371 goto bail; 372 373 if (si->si_extended) 374 si->si_slots_per_block = 375 (osb->sb->s_blocksize / 376 sizeof(struct ocfs2_extended_slot)); 377 else 378 si->si_slots_per_block = osb->sb->s_blocksize / sizeof(__le16); 379 380 /* The size checks above should ensure this */ 381 BUG_ON((osb->max_slots / si->si_slots_per_block) > blocks); 382 383 trace_ocfs2_map_slot_buffers(bytes, si->si_blocks); 384 385 si->si_bh = kzalloc(sizeof(struct buffer_head *) * si->si_blocks, 386 GFP_KERNEL); 387 if (!si->si_bh) { 388 status = -ENOMEM; 389 mlog_errno(status); 390 goto bail; 391 } 392 393 for (i = 0; i < si->si_blocks; i++) { 394 status = ocfs2_extent_map_get_blocks(si->si_inode, i, 395 &blkno, NULL, NULL); 396 if (status < 0) { 397 mlog_errno(status); 398 goto bail; 399 } 400 401 trace_ocfs2_map_slot_buffers_block((unsigned long long)blkno, i); 402 403 bh = NULL; /* Acquire a fresh bh */ 404 status = ocfs2_read_blocks(INODE_CACHE(si->si_inode), blkno, 405 1, &bh, OCFS2_BH_IGNORE_CACHE, NULL); 406 if (status < 0) { 407 mlog_errno(status); 408 goto bail; 409 } 410 411 si->si_bh[i] = bh; 412 } 413 414 bail: 415 return status; 416 } 417 418 int ocfs2_init_slot_info(struct ocfs2_super *osb) 419 { 420 int status; 421 struct inode *inode = NULL; 422 struct ocfs2_slot_info *si; 423 424 si = kzalloc(sizeof(struct ocfs2_slot_info) + 425 (sizeof(struct ocfs2_slot) * osb->max_slots), 426 GFP_KERNEL); 427 if (!si) { 428 status = -ENOMEM; 429 mlog_errno(status); 430 goto bail; 431 } 432 433 si->si_extended = ocfs2_uses_extended_slot_map(osb); 434 si->si_num_slots = osb->max_slots; 435 si->si_slots = (struct ocfs2_slot *)((char *)si + 436 sizeof(struct ocfs2_slot_info)); 437 438 inode = ocfs2_get_system_file_inode(osb, SLOT_MAP_SYSTEM_INODE, 439 OCFS2_INVALID_SLOT); 440 if (!inode) { 441 status = -EINVAL; 442 mlog_errno(status); 443 goto bail; 444 } 445 446 si->si_inode = inode; 447 status = ocfs2_map_slot_buffers(osb, si); 448 if (status < 0) { 449 mlog_errno(status); 450 goto bail; 451 } 452 453 osb->slot_info = (struct ocfs2_slot_info *)si; 454 bail: 455 if (status < 0 && si) 456 __ocfs2_free_slot_info(si); 457 458 return status; 459 } 460 461 void ocfs2_free_slot_info(struct ocfs2_super *osb) 462 { 463 struct ocfs2_slot_info *si = osb->slot_info; 464 465 osb->slot_info = NULL; 466 __ocfs2_free_slot_info(si); 467 } 468 469 int ocfs2_find_slot(struct ocfs2_super *osb) 470 { 471 int status; 472 int slot; 473 struct ocfs2_slot_info *si; 474 475 si = osb->slot_info; 476 477 spin_lock(&osb->osb_lock); 478 ocfs2_update_slot_info(si); 479 480 /* search for ourselves first and take the slot if it already 481 * exists. Perhaps we need to mark this in a variable for our 482 * own journal recovery? Possibly not, though we certainly 483 * need to warn to the user */ 484 slot = __ocfs2_node_num_to_slot(si, osb->node_num); 485 if (slot < 0) { 486 /* if no slot yet, then just take 1st available 487 * one. */ 488 slot = __ocfs2_find_empty_slot(si, osb->preferred_slot); 489 if (slot < 0) { 490 spin_unlock(&osb->osb_lock); 491 mlog(ML_ERROR, "no free slots available!\n"); 492 status = -EINVAL; 493 goto bail; 494 } 495 } else 496 printk(KERN_INFO "ocfs2: Slot %d on device (%s) was already " 497 "allocated to this node!\n", slot, osb->dev_str); 498 499 ocfs2_set_slot(si, slot, osb->node_num); 500 osb->slot_num = slot; 501 spin_unlock(&osb->osb_lock); 502 503 trace_ocfs2_find_slot(osb->slot_num); 504 505 status = ocfs2_update_disk_slot(osb, si, osb->slot_num); 506 if (status < 0) 507 mlog_errno(status); 508 509 bail: 510 return status; 511 } 512 513 void ocfs2_put_slot(struct ocfs2_super *osb) 514 { 515 int status, slot_num; 516 struct ocfs2_slot_info *si = osb->slot_info; 517 518 if (!si) 519 return; 520 521 spin_lock(&osb->osb_lock); 522 ocfs2_update_slot_info(si); 523 524 slot_num = osb->slot_num; 525 ocfs2_invalidate_slot(si, osb->slot_num); 526 osb->slot_num = OCFS2_INVALID_SLOT; 527 spin_unlock(&osb->osb_lock); 528 529 status = ocfs2_update_disk_slot(osb, si, slot_num); 530 if (status < 0) { 531 mlog_errno(status); 532 goto bail; 533 } 534 535 bail: 536 ocfs2_free_slot_info(osb); 537 } 538 539