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"
45 struct ocfs2_slot_info {
46 struct inode *si_inode;
47 unsigned int si_blocks;
48 struct buffer_head **si_bh;
49 unsigned int si_num_slots;
51 s16 si_global_node_nums[OCFS2_MAX_SLOTS];
55 static s16 __ocfs2_node_num_to_slot(struct ocfs2_slot_info *si,
57 static void __ocfs2_fill_slot(struct ocfs2_slot_info *si,
62 * Post the slot information on disk into our slot_info struct.
63 * Must be protected by osb_lock.
65 static void ocfs2_update_slot_info(struct ocfs2_slot_info *si)
70 /* we don't read the slot block here as ocfs2_super_lock
71 * should've made sure we have the most recent copy. */
72 disk_info = (__le16 *) si->si_bh[0]->b_data;
74 for (i = 0; i < si->si_size; i++)
75 si->si_global_node_nums[i] = le16_to_cpu(disk_info[i]);
78 int ocfs2_refresh_slot_info(struct ocfs2_super *osb)
81 struct ocfs2_slot_info *si = osb->slot_info;
86 BUG_ON(si->si_blocks == 0);
87 BUG_ON(si->si_bh == NULL);
89 mlog(0, "Refreshing slot map, reading %u block(s)\n",
93 * We pass -1 as blocknr because we expect all of si->si_bh to
94 * be !NULL. Thus, ocfs2_read_blocks() will ignore blocknr. If
95 * this is not true, the read of -1 (UINT64_MAX) will fail.
97 ret = ocfs2_read_blocks(osb, -1, si->si_blocks, si->si_bh, 0,
100 spin_lock(&osb->osb_lock);
101 ocfs2_update_slot_info(si);
102 spin_unlock(&osb->osb_lock);
108 /* post the our slot info stuff into it's destination bh and write it
110 static int ocfs2_update_disk_slots(struct ocfs2_super *osb,
111 struct ocfs2_slot_info *si)
114 __le16 *disk_info = (__le16 *) si->si_bh[0]->b_data;
116 spin_lock(&osb->osb_lock);
117 for (i = 0; i < si->si_size; i++)
118 disk_info[i] = cpu_to_le16(si->si_global_node_nums[i]);
119 spin_unlock(&osb->osb_lock);
121 status = ocfs2_write_block(osb, si->si_bh[0], si->si_inode);
129 * Calculate how many bytes are needed by the slot map. Returns
130 * an error if the slot map file is too small.
132 static int ocfs2_slot_map_physical_size(struct ocfs2_super *osb,
134 unsigned long long *bytes)
136 unsigned long long bytes_needed;
138 bytes_needed = osb->max_slots * sizeof(__le16);
139 if (bytes_needed > i_size_read(inode)) {
141 "Slot map file is too small! (size %llu, needed %llu)\n",
142 i_size_read(inode), bytes_needed);
146 *bytes = bytes_needed;
150 /* try to find global node in the slot info. Returns
151 * OCFS2_INVALID_SLOT if nothing is found. */
152 static s16 __ocfs2_node_num_to_slot(struct ocfs2_slot_info *si,
156 s16 ret = OCFS2_INVALID_SLOT;
158 for(i = 0; i < si->si_num_slots; i++) {
159 if (global == si->si_global_node_nums[i]) {
167 static s16 __ocfs2_find_empty_slot(struct ocfs2_slot_info *si,
171 s16 ret = OCFS2_INVALID_SLOT;
173 if (preferred >= 0 && preferred < si->si_num_slots) {
174 if (OCFS2_INVALID_SLOT == si->si_global_node_nums[preferred]) {
180 for(i = 0; i < si->si_num_slots; i++) {
181 if (OCFS2_INVALID_SLOT == si->si_global_node_nums[i]) {
190 int ocfs2_node_num_to_slot(struct ocfs2_super *osb, unsigned int node_num)
193 struct ocfs2_slot_info *si = osb->slot_info;
195 spin_lock(&osb->osb_lock);
196 slot = __ocfs2_node_num_to_slot(si, node_num);
197 spin_unlock(&osb->osb_lock);
199 if (slot == OCFS2_INVALID_SLOT)
205 int ocfs2_slot_to_node_num_locked(struct ocfs2_super *osb, int slot_num,
206 unsigned int *node_num)
208 struct ocfs2_slot_info *si = osb->slot_info;
210 assert_spin_locked(&osb->osb_lock);
212 BUG_ON(slot_num < 0);
213 BUG_ON(slot_num > osb->max_slots);
215 if (si->si_global_node_nums[slot_num] == OCFS2_INVALID_SLOT)
218 *node_num = si->si_global_node_nums[slot_num];
222 static void __ocfs2_free_slot_info(struct ocfs2_slot_info *si)
232 for (i = 0; i < si->si_blocks; i++) {
234 brelse(si->si_bh[i]);
244 static void __ocfs2_fill_slot(struct ocfs2_slot_info *si,
248 BUG_ON(slot_num == OCFS2_INVALID_SLOT);
249 BUG_ON(slot_num >= si->si_num_slots);
250 BUG_ON((node_num != O2NM_INVALID_NODE_NUM) &&
251 (node_num >= O2NM_MAX_NODES));
253 si->si_global_node_nums[slot_num] = node_num;
256 int ocfs2_clear_slot(struct ocfs2_super *osb, s16 slot_num)
258 struct ocfs2_slot_info *si = osb->slot_info;
263 spin_lock(&osb->osb_lock);
264 __ocfs2_fill_slot(si, slot_num, OCFS2_INVALID_SLOT);
265 spin_unlock(&osb->osb_lock);
267 return ocfs2_update_disk_slots(osb, osb->slot_info);
270 static int ocfs2_map_slot_buffers(struct ocfs2_super *osb,
271 struct ocfs2_slot_info *si)
275 unsigned long long blocks, bytes;
277 struct buffer_head *bh;
279 status = ocfs2_slot_map_physical_size(osb, si->si_inode, &bytes);
283 blocks = ocfs2_blocks_for_bytes(si->si_inode->i_sb, bytes);
284 BUG_ON(blocks > UINT_MAX);
285 si->si_blocks = blocks;
289 mlog(0, "Slot map needs %u buffers for %llu bytes\n",
290 si->si_blocks, bytes);
292 si->si_bh = kzalloc(sizeof(struct buffer_head *) * si->si_blocks,
300 for (i = 0; i < si->si_blocks; i++) {
301 status = ocfs2_extent_map_get_blocks(si->si_inode, i,
308 mlog(0, "Reading slot map block %u at %llu\n", i,
309 (unsigned long long)blkno);
311 bh = NULL; /* Acquire a fresh bh */
312 status = ocfs2_read_block(osb, blkno, &bh, 0, si->si_inode);
325 int ocfs2_init_slot_info(struct ocfs2_super *osb)
328 struct inode *inode = NULL;
329 struct ocfs2_slot_info *si;
331 si = kzalloc(sizeof(struct ocfs2_slot_info), GFP_KERNEL);
338 si->si_num_slots = osb->max_slots;
339 si->si_size = OCFS2_MAX_SLOTS;
341 for(i = 0; i < si->si_num_slots; i++)
342 si->si_global_node_nums[i] = OCFS2_INVALID_SLOT;
344 inode = ocfs2_get_system_file_inode(osb, SLOT_MAP_SYSTEM_INODE,
352 si->si_inode = inode;
353 status = ocfs2_map_slot_buffers(osb, si);
359 osb->slot_info = (struct ocfs2_slot_info *)si;
361 if (status < 0 && si)
362 __ocfs2_free_slot_info(si);
367 void ocfs2_free_slot_info(struct ocfs2_super *osb)
369 struct ocfs2_slot_info *si = osb->slot_info;
371 osb->slot_info = NULL;
372 __ocfs2_free_slot_info(si);
375 int ocfs2_find_slot(struct ocfs2_super *osb)
379 struct ocfs2_slot_info *si;
385 spin_lock(&osb->osb_lock);
386 ocfs2_update_slot_info(si);
388 /* search for ourselves first and take the slot if it already
389 * exists. Perhaps we need to mark this in a variable for our
390 * own journal recovery? Possibly not, though we certainly
391 * need to warn to the user */
392 slot = __ocfs2_node_num_to_slot(si, osb->node_num);
393 if (slot == OCFS2_INVALID_SLOT) {
394 /* if no slot yet, then just take 1st available
396 slot = __ocfs2_find_empty_slot(si, osb->preferred_slot);
397 if (slot == OCFS2_INVALID_SLOT) {
398 spin_unlock(&osb->osb_lock);
399 mlog(ML_ERROR, "no free slots available!\n");
404 mlog(ML_NOTICE, "slot %d is already allocated to this node!\n",
407 __ocfs2_fill_slot(si, slot, osb->node_num);
408 osb->slot_num = slot;
409 spin_unlock(&osb->osb_lock);
411 mlog(0, "taking node slot %d\n", osb->slot_num);
413 status = ocfs2_update_disk_slots(osb, si);
422 void ocfs2_put_slot(struct ocfs2_super *osb)
425 struct ocfs2_slot_info *si = osb->slot_info;
430 spin_lock(&osb->osb_lock);
431 ocfs2_update_slot_info(si);
433 __ocfs2_fill_slot(si, osb->slot_num, OCFS2_INVALID_SLOT);
434 osb->slot_num = OCFS2_INVALID_SLOT;
435 spin_unlock(&osb->osb_lock);
437 status = ocfs2_update_disk_slots(osb, si);
444 ocfs2_free_slot_info(osb);