1 /* -*- mode: c; c-basic-offset: 8; -*-
2 * vim: noexpandtab sw=8 ts=8 sts=0:
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>
36 #include "extent_map.h"
37 #include "heartbeat.h"
43 #include "buffer_head_io.h"
48 unsigned int sl_node_num;
51 struct ocfs2_slot_info {
52 struct inode *si_inode;
53 unsigned int si_blocks;
54 struct buffer_head **si_bh;
55 unsigned int si_num_slots;
56 struct ocfs2_slot *si_slots;
60 static int __ocfs2_node_num_to_slot(struct ocfs2_slot_info *si,
61 unsigned int node_num);
63 static void ocfs2_invalidate_slot(struct ocfs2_slot_info *si,
66 BUG_ON((slot_num < 0) || (slot_num >= si->si_num_slots));
67 si->si_slots[slot_num].sl_valid = 0;
70 static void ocfs2_set_slot(struct ocfs2_slot_info *si,
71 int slot_num, unsigned int node_num)
73 BUG_ON((slot_num < 0) || (slot_num >= si->si_num_slots));
74 BUG_ON((node_num == O2NM_INVALID_NODE_NUM) ||
75 (node_num >= O2NM_MAX_NODES));
77 si->si_slots[slot_num].sl_valid = 1;
78 si->si_slots[slot_num].sl_node_num = node_num;
82 * Post the slot information on disk into our slot_info struct.
83 * Must be protected by osb_lock.
85 static void ocfs2_update_slot_info(struct ocfs2_slot_info *si)
90 /* we don't read the slot block here as ocfs2_super_lock
91 * should've made sure we have the most recent copy. */
92 disk_info = (__le16 *) si->si_bh[0]->b_data;
94 for (i = 0; i < si->si_num_slots; i++) {
95 if (le16_to_cpu(disk_info[i]) == (u16)OCFS2_INVALID_SLOT)
96 ocfs2_invalidate_slot(si, i);
98 ocfs2_set_slot(si, i, le16_to_cpu(disk_info[i]));
102 int ocfs2_refresh_slot_info(struct ocfs2_super *osb)
105 struct ocfs2_slot_info *si = osb->slot_info;
110 BUG_ON(si->si_blocks == 0);
111 BUG_ON(si->si_bh == NULL);
113 mlog(0, "Refreshing slot map, reading %u block(s)\n",
117 * We pass -1 as blocknr because we expect all of si->si_bh to
118 * be !NULL. Thus, ocfs2_read_blocks() will ignore blocknr. If
119 * this is not true, the read of -1 (UINT64_MAX) will fail.
121 ret = ocfs2_read_blocks(osb, -1, si->si_blocks, si->si_bh, 0,
124 spin_lock(&osb->osb_lock);
125 ocfs2_update_slot_info(si);
126 spin_unlock(&osb->osb_lock);
132 /* post the our slot info stuff into it's destination bh and write it
134 static int ocfs2_update_disk_slots(struct ocfs2_super *osb,
135 struct ocfs2_slot_info *si)
138 __le16 *disk_info = (__le16 *) si->si_bh[0]->b_data;
140 spin_lock(&osb->osb_lock);
141 for (i = 0; i < si->si_num_slots; i++) {
142 if (si->si_slots[i].sl_valid)
144 cpu_to_le16(si->si_slots[i].sl_node_num);
146 disk_info[i] = cpu_to_le16(OCFS2_INVALID_SLOT);
148 spin_unlock(&osb->osb_lock);
150 status = ocfs2_write_block(osb, si->si_bh[0], si->si_inode);
158 * Calculate how many bytes are needed by the slot map. Returns
159 * an error if the slot map file is too small.
161 static int ocfs2_slot_map_physical_size(struct ocfs2_super *osb,
163 unsigned long long *bytes)
165 unsigned long long bytes_needed;
167 bytes_needed = osb->max_slots * sizeof(__le16);
168 if (bytes_needed > i_size_read(inode)) {
170 "Slot map file is too small! (size %llu, needed %llu)\n",
171 i_size_read(inode), bytes_needed);
175 *bytes = bytes_needed;
179 /* try to find global node in the slot info. Returns -ENOENT
180 * if nothing is found. */
181 static int __ocfs2_node_num_to_slot(struct ocfs2_slot_info *si,
182 unsigned int node_num)
184 int i, ret = -ENOENT;
186 for(i = 0; i < si->si_num_slots; i++) {
187 if (si->si_slots[i].sl_valid &&
188 (node_num == si->si_slots[i].sl_node_num)) {
197 static int __ocfs2_find_empty_slot(struct ocfs2_slot_info *si,
200 int i, ret = -ENOSPC;
202 if ((preferred >= 0) && (preferred < si->si_num_slots)) {
203 if (!si->si_slots[preferred].sl_valid) {
209 for(i = 0; i < si->si_num_slots; i++) {
210 if (!si->si_slots[i].sl_valid) {
219 int ocfs2_node_num_to_slot(struct ocfs2_super *osb, unsigned int node_num)
222 struct ocfs2_slot_info *si = osb->slot_info;
224 spin_lock(&osb->osb_lock);
225 slot = __ocfs2_node_num_to_slot(si, node_num);
226 spin_unlock(&osb->osb_lock);
231 int ocfs2_slot_to_node_num_locked(struct ocfs2_super *osb, int slot_num,
232 unsigned int *node_num)
234 struct ocfs2_slot_info *si = osb->slot_info;
236 assert_spin_locked(&osb->osb_lock);
238 BUG_ON(slot_num < 0);
239 BUG_ON(slot_num > osb->max_slots);
241 if (!si->si_slots[slot_num].sl_valid)
244 *node_num = si->si_slots[slot_num].sl_node_num;
248 static void __ocfs2_free_slot_info(struct ocfs2_slot_info *si)
258 for (i = 0; i < si->si_blocks; i++) {
260 brelse(si->si_bh[i]);
270 int ocfs2_clear_slot(struct ocfs2_super *osb, int slot_num)
272 struct ocfs2_slot_info *si = osb->slot_info;
277 spin_lock(&osb->osb_lock);
278 ocfs2_invalidate_slot(si, slot_num);
279 spin_unlock(&osb->osb_lock);
281 return ocfs2_update_disk_slots(osb, osb->slot_info);
284 static int ocfs2_map_slot_buffers(struct ocfs2_super *osb,
285 struct ocfs2_slot_info *si)
289 unsigned long long blocks, bytes;
291 struct buffer_head *bh;
293 status = ocfs2_slot_map_physical_size(osb, si->si_inode, &bytes);
297 blocks = ocfs2_blocks_for_bytes(si->si_inode->i_sb, bytes);
298 BUG_ON(blocks > UINT_MAX);
299 si->si_blocks = blocks;
303 mlog(0, "Slot map needs %u buffers for %llu bytes\n",
304 si->si_blocks, bytes);
306 si->si_bh = kzalloc(sizeof(struct buffer_head *) * si->si_blocks,
314 for (i = 0; i < si->si_blocks; i++) {
315 status = ocfs2_extent_map_get_blocks(si->si_inode, i,
322 mlog(0, "Reading slot map block %u at %llu\n", i,
323 (unsigned long long)blkno);
325 bh = NULL; /* Acquire a fresh bh */
326 status = ocfs2_read_block(osb, blkno, &bh, 0, si->si_inode);
339 int ocfs2_init_slot_info(struct ocfs2_super *osb)
342 struct inode *inode = NULL;
343 struct ocfs2_slot_info *si;
345 si = kzalloc(sizeof(struct ocfs2_slot_info) +
346 (sizeof(struct ocfs2_slot) * osb->max_slots),
354 si->si_num_slots = osb->max_slots;
355 si->si_slots = (struct ocfs2_slot *)((char *)si +
356 sizeof(struct ocfs2_slot_info));
358 inode = ocfs2_get_system_file_inode(osb, SLOT_MAP_SYSTEM_INODE,
366 si->si_inode = inode;
367 status = ocfs2_map_slot_buffers(osb, si);
373 osb->slot_info = (struct ocfs2_slot_info *)si;
375 if (status < 0 && si)
376 __ocfs2_free_slot_info(si);
381 void ocfs2_free_slot_info(struct ocfs2_super *osb)
383 struct ocfs2_slot_info *si = osb->slot_info;
385 osb->slot_info = NULL;
386 __ocfs2_free_slot_info(si);
389 int ocfs2_find_slot(struct ocfs2_super *osb)
393 struct ocfs2_slot_info *si;
399 spin_lock(&osb->osb_lock);
400 ocfs2_update_slot_info(si);
402 /* search for ourselves first and take the slot if it already
403 * exists. Perhaps we need to mark this in a variable for our
404 * own journal recovery? Possibly not, though we certainly
405 * need to warn to the user */
406 slot = __ocfs2_node_num_to_slot(si, osb->node_num);
408 /* if no slot yet, then just take 1st available
410 slot = __ocfs2_find_empty_slot(si, osb->preferred_slot);
412 spin_unlock(&osb->osb_lock);
413 mlog(ML_ERROR, "no free slots available!\n");
418 mlog(ML_NOTICE, "slot %d is already allocated to this node!\n",
421 ocfs2_set_slot(si, slot, osb->node_num);
422 osb->slot_num = slot;
423 spin_unlock(&osb->osb_lock);
425 mlog(0, "taking node slot %d\n", osb->slot_num);
427 status = ocfs2_update_disk_slots(osb, si);
436 void ocfs2_put_slot(struct ocfs2_super *osb)
439 struct ocfs2_slot_info *si = osb->slot_info;
444 spin_lock(&osb->osb_lock);
445 ocfs2_update_slot_info(si);
447 ocfs2_invalidate_slot(si, osb->slot_num);
448 osb->slot_num = OCFS2_INVALID_SLOT;
449 spin_unlock(&osb->osb_lock);
451 status = ocfs2_update_disk_slots(osb, si);
458 ocfs2_free_slot_info(osb);