2 * Copyright (c) 2008 The DragonFly Project. All rights reserved.
4 * This code is derived from software contributed to The DragonFly Project
5 * by Matthew Dillon <dillon@backplane.com>
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in
15 * the documentation and/or other materials provided with the
17 * 3. Neither the name of The DragonFly Project nor the names of its
18 * contributors may be used to endorse or promote products derived
19 * from this software without specific, prior written permission.
21 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
24 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
25 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
26 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
27 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
28 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
29 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
30 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
31 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * $DragonFly: src/sys/vfs/hammer/hammer_recover.c,v 1.15 2008/05/04 09:06:45 dillon Exp $
39 static int hammer_check_tail_signature(hammer_fifo_tail_t tail,
40 hammer_off_t end_off);
41 static void hammer_recover_copy_undo(hammer_off_t undo_offset,
42 char *src, char *dst, int bytes);
44 static void hammer_recover_debug_dump(int w, char *buf, int bytes);
46 static int hammer_recover_undo(hammer_mount_t hmp, hammer_fifo_undo_t undo,
50 * Recover a filesystem on mount
52 * NOTE: No information from the root volume has been cached in the
53 * hammer_mount structure yet, so we need to access the root volume's
57 hammer_recover(hammer_mount_t hmp, hammer_volume_t root_volume)
59 hammer_blockmap_t rootmap;
60 hammer_buffer_t buffer;
61 hammer_off_t scan_offset;
63 hammer_fifo_tail_t tail;
64 hammer_fifo_undo_t undo;
68 * Examine the UNDO FIFO. If it is empty the filesystem is clean
69 * and no action need be taken.
71 * NOTE: hmp->blockmap has not been initialized yet so use the
72 * root volume's ondisk buffer directly.
74 rootmap = &root_volume->ondisk->vol0_blockmap[HAMMER_ZONE_UNDO_INDEX];
75 hmp->flusher_undo_start = rootmap->next_offset;
77 if (rootmap->first_offset == rootmap->next_offset)
80 if (rootmap->next_offset >= rootmap->first_offset) {
81 bytes = rootmap->next_offset - rootmap->first_offset;
83 bytes = rootmap->alloc_offset - rootmap->first_offset +
84 (rootmap->next_offset & HAMMER_OFF_LONG_MASK);
86 kprintf("HAMMER(%s) Start Recovery (%lld bytes of UNDO)\n",
87 root_volume->ondisk->vol_name, bytes);
88 if (bytes > (rootmap->alloc_offset & HAMMER_OFF_LONG_MASK)) {
89 kprintf("Undo size is absurd, unable to mount\n");
94 * Scan the UNDOs backwards.
96 scan_offset = rootmap->next_offset;
98 if (scan_offset > rootmap->alloc_offset) {
99 kprintf("HAMMER(%s) UNDO record at %016llx FIFO overflow\n",
100 root_volume->ondisk->vol_name,
106 while ((int64_t)bytes > 0) {
107 if (hammer_debug_general & 0x0080)
108 kprintf("scan_offset %016llx\n", scan_offset);
109 if (scan_offset == HAMMER_ZONE_ENCODE(HAMMER_ZONE_UNDO_INDEX, 0)) {
110 scan_offset = rootmap->alloc_offset;
113 if (scan_offset - sizeof(*tail) <
114 HAMMER_ZONE_ENCODE(HAMMER_ZONE_UNDO_INDEX, 0)) {
115 kprintf("HAMMER(%s) UNDO record at %016llx FIFO "
117 root_volume->ondisk->vol_name,
122 tail = hammer_bread(hmp, scan_offset - sizeof(*tail),
125 kprintf("HAMMER(%s) Unable to read UNDO TAIL "
127 root_volume->ondisk->vol_name,
128 scan_offset - sizeof(*tail));
132 if (hammer_check_tail_signature(tail, scan_offset) != 0) {
133 kprintf("HAMMER(%s) Illegal UNDO TAIL signature "
135 root_volume->ondisk->vol_name,
136 scan_offset - sizeof(*tail));
140 undo = (void *)((char *)tail + sizeof(*tail) - tail->tail_size);
142 error = hammer_recover_undo(hmp, undo,
144 (int)((char *)undo - (char *)buffer->ondisk));
146 kprintf("HAMMER(%s) UNDO record at %016llx failed\n",
147 root_volume->ondisk->vol_name,
148 scan_offset - tail->tail_size);
151 scan_offset -= tail->tail_size;
152 bytes -= tail->tail_size;
156 * Reload flusher_undo_start to kick off the UNDO sequencing.
158 hmp->flusher_undo_start = rootmap->next_offset;
160 hammer_rel_buffer(buffer, 0);
165 hammer_check_tail_signature(hammer_fifo_tail_t tail, hammer_off_t end_off)
169 max_bytes = ((end_off - sizeof(*tail)) & HAMMER_BUFMASK);
170 max_bytes += sizeof(*tail);
173 * tail overlaps buffer boundary
175 if (((end_off - sizeof(*tail)) ^ (end_off - 1)) & ~HAMMER_BUFMASK64) {
180 * signature check, the tail signature is allowed to be the head
181 * signature only for 8-byte PADs.
183 switch(tail->tail_signature) {
184 case HAMMER_TAIL_SIGNATURE:
186 case HAMMER_HEAD_SIGNATURE:
187 if (tail->tail_type != HAMMER_HEAD_TYPE_PAD ||
188 tail->tail_size != sizeof(*tail)) {
195 * The undo structure must not overlap a buffer boundary.
197 if (tail->tail_size < 0 || tail->tail_size > max_bytes) {
204 hammer_recover_undo(hammer_mount_t hmp, hammer_fifo_undo_t undo, int bytes)
206 hammer_fifo_tail_t tail;
207 hammer_volume_t volume;
208 hammer_buffer_t buffer;
216 * Basic sanity checks
218 if (bytes < HAMMER_HEAD_ALIGN) {
219 kprintf("HAMMER: Undo alignment error (%d)\n", bytes);
222 if (undo->head.hdr_signature != HAMMER_HEAD_SIGNATURE) {
223 kprintf("HAMMER: Bad head signature %04x\n",
224 undo->head.hdr_signature);
227 if (undo->head.hdr_size < HAMMER_HEAD_ALIGN ||
228 undo->head.hdr_size > bytes) {
229 kprintf("HAMMER: Bad size %d\n", bytes);
234 * Skip PAD records. Note that PAD records also do not require
237 if (undo->head.hdr_type == HAMMER_HEAD_TYPE_PAD)
243 bytes = undo->head.hdr_size;
244 tail = (void *)((char *)undo + bytes - sizeof(*tail));
245 if (tail->tail_size != undo->head.hdr_size) {
246 kprintf("HAMMER: Bad tail size %d\n", tail->tail_size);
249 if (tail->tail_type != undo->head.hdr_type) {
250 kprintf("HAMMER: Bad tail type %d\n", tail->tail_type);
255 * Only process UNDO records
257 if (undo->head.hdr_type != HAMMER_HEAD_TYPE_UNDO)
261 * Validate the UNDO record.
263 max_bytes = undo->head.hdr_size - sizeof(*undo) - sizeof(*tail);
264 if (undo->undo_data_bytes < 0 || undo->undo_data_bytes > max_bytes) {
265 kprintf("HAMMER: Corrupt UNDO record, undo_data_bytes %d/%d\n",
266 undo->undo_data_bytes, max_bytes);
271 * The undo offset may only be a zone-1 or zone-2 offset.
273 * Currently we only support a zone-1 offset representing the
276 zone = HAMMER_ZONE_DECODE(undo->undo_offset);
277 offset = undo->undo_offset & HAMMER_BUFMASK;
279 if (offset + undo->undo_data_bytes > HAMMER_BUFSIZE) {
280 kprintf("HAMMER: Corrupt UNDO record, bad offset\n");
285 case HAMMER_ZONE_RAW_VOLUME_INDEX:
286 vol_no = HAMMER_VOL_DECODE(undo->undo_offset);
287 volume = hammer_get_volume(hmp, vol_no, &error);
288 if (volume == NULL) {
289 kprintf("HAMMER: UNDO record, "
290 "cannot access volume %d\n", vol_no);
293 hammer_modify_volume(NULL, volume, NULL, 0);
294 hammer_recover_copy_undo(undo->undo_offset,
296 (char *)volume->ondisk + offset,
297 undo->undo_data_bytes);
298 hammer_modify_volume_done(volume);
299 hammer_io_flush(&volume->io);
300 hammer_rel_volume(volume, 0);
302 case HAMMER_ZONE_RAW_BUFFER_INDEX:
303 buffer = hammer_get_buffer(hmp, undo->undo_offset, 0, &error);
304 if (buffer == NULL) {
305 kprintf("HAMMER: UNDO record, "
306 "cannot access buffer %016llx\n",
310 hammer_modify_buffer(NULL, buffer, NULL, 0);
311 hammer_recover_copy_undo(undo->undo_offset,
313 (char *)buffer->ondisk + offset,
314 undo->undo_data_bytes);
315 hammer_modify_buffer_done(buffer);
316 hammer_io_flush(&buffer->io);
317 hammer_rel_buffer(buffer, 0);
320 kprintf("HAMMER: Corrupt UNDO record\n");
327 hammer_recover_copy_undo(hammer_off_t undo_offset,
328 char *src, char *dst, int bytes)
331 if (hammer_debug_general & 0x0080)
332 kprintf("NDO %016llx: %d\n", undo_offset, bytes);
334 kprintf("UNDO %016llx:", undo_offset);
335 hammer_recover_debug_dump(22, dst, bytes);
336 kprintf("%22s", "to:");
337 hammer_recover_debug_dump(22, src, bytes);
339 bcopy(src, dst, bytes);
345 hammer_recover_debug_dump(int w, char *buf, int bytes)
349 for (i = 0; i < bytes; ++i) {
350 if (i && (i & 15) == 0)
351 kprintf("\n%*.*s", w, w, "");
352 kprintf(" %02x", (unsigned char)buf[i]);