sbin/hammer/cmd_strip.c

   1 /*
   2  * Copyright (c) 2007-2016 The DragonFly Project.  All rights reserved.
   3  *
   4  * This code is derived from software contributed to The DragonFly Project
   5  * by Matthew Dillon <dillon@backplane.com>
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  *
  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
  16  *    distribution.
  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.
  20  *
  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
  32  * SUCH DAMAGE.
  33  */
  34
  35 #include "hammer.h"
  36
  37 static int hammer_test_offset(const char *msg, hammer_off_t offset);
  38 static void hammer_strip_bigblock(int zone, hammer_off_t offset);
  39 static void hammer_ask_yn(void);
  40
  41 void
  42 hammer_cmd_strip(void)
  43 {
  44         volume_info_t volume;
  45         hammer_blockmap_t rootmap;
  46         hammer_blockmap_layer1_t layer1;
  47         hammer_blockmap_layer2_t layer2;
  48         buffer_info_t buffer1 = NULL;
  49         buffer_info_t buffer2 = NULL;
  50         hammer_off_t layer1_offset;
  51         hammer_off_t layer2_offset;
  52         hammer_off_t phys_offset;
  53         hammer_off_t block_offset;
  54         hammer_off_t offset;
  55         int i, zone = HAMMER_ZONE_FREEMAP_INDEX;
  56
  57         hammer_ask_yn();
  58
  59         volume = get_root_volume();
  60         if (volume == NULL) {
  61                 printf("No root volume found\n");
  62                 goto strip_header;
  63         }
  64
  65         rootmap = &volume->ondisk->vol0_blockmap[zone];
  66         if (!hammer_test_offset("layer1 physical", rootmap->phys_offset))
  67                 goto strip_header;
  68
  69         for (phys_offset = HAMMER_ZONE_ENCODE(zone, 0);
  70              phys_offset < HAMMER_ZONE_ENCODE(zone, HAMMER_OFF_LONG_MASK);
  71              phys_offset += HAMMER_BLOCKMAP_LAYER2) {
  72                 /*
  73                  * Dive layer 1.
  74                  */
  75                 layer1_offset = rootmap->phys_offset +
  76                                 HAMMER_BLOCKMAP_LAYER1_OFFSET(phys_offset);
  77                 if (!hammer_test_offset("layer1", layer1_offset))
  78                         break;
  79                 layer1 = get_buffer_data(layer1_offset, &buffer1, 0);
  80
  81                 if (layer1->phys_offset == HAMMER_BLOCKMAP_UNAVAIL)
  82                         continue;
  83
  84                 for (block_offset = 0;
  85                      block_offset < HAMMER_BLOCKMAP_LAYER2;
  86                      block_offset += HAMMER_BIGBLOCK_SIZE) {
  87                         offset = phys_offset + block_offset;
  88                         /*
  89                          * Dive layer 2, each entry represents a big-block.
  90                          */
  91                         layer2_offset = layer1->phys_offset +
  92                                         HAMMER_BLOCKMAP_LAYER2_OFFSET(block_offset);
  93                         if (!hammer_test_offset("layer2", layer2_offset))
  94                                 break;
  95                         layer2 = get_buffer_data(layer2_offset, &buffer2, 0);
  96
  97                         if (layer2->zone == HAMMER_ZONE_BTREE_INDEX ||
  98                             layer2->zone == HAMMER_ZONE_META_INDEX) {
  99                                 hammer_strip_bigblock(layer2->zone, offset);
 100                                 layer2->zone = HAMMER_ZONE_UNAVAIL_INDEX;
 101                                 layer2->append_off = HAMMER_BIGBLOCK_SIZE;
 102                                 layer2->bytes_free = 0;
 103                                 hammer_crc_set_layer2(HammerVersion, layer2);
 104                                 buffer2->cache.modified = 1;
 105                         } else if (layer2->zone == HAMMER_ZONE_UNAVAIL_INDEX) {
 106                                 break;
 107                         }
 108                 }
 109         }
 110         rel_buffer(buffer1);
 111         rel_buffer(buffer2);
 112
 113 strip_header:
 114         for (i = 0; i < HAMMER_MAX_VOLUMES; i++) {
 115                 volume = get_volume(i);
 116                 if (volume) {
 117                         bzero(volume->ondisk, sizeof(*volume->ondisk));
 118                         memcpy(&volume->ondisk->vol_signature, "STRIPPED", 8);
 119                         printf("Stripped volume header %s\n", volume->name);
 120                 }
 121         }
 122
 123         flush_all_volumes();
 124 }
 125
 126 static
 127 int
 128 hammer_test_offset(const char *msg, hammer_off_t offset)
 129 {
 130         if (get_volume(HAMMER_VOL_DECODE(offset)) == NULL) {
 131                 printf("Invalid volume# %d\n", HAMMER_VOL_DECODE(offset));
 132                 return(0);
 133         }
 134         if (!hammer_is_zone_raw_buffer(offset)) {
 135                 printf("Invalid %s offset 0x%jx\n", msg, offset);
 136                 return(0);
 137         }
 138
 139         return(1);
 140 }
 141
 142 static
 143 void
 144 hammer_strip_bigblock(int zone, hammer_off_t offset)
 145 {
 146         buffer_info_t buffer = NULL;
 147         int i;
 148
 149         assert(hammer_is_index_record(zone));
 150         assert((offset & HAMMER_BIGBLOCK_MASK64) == 0);
 151         assert((offset & HAMMER_BUFMASK) == 0);
 152         offset = hammer_xlate_to_zoneX(zone, offset);
 153
 154         /*
 155          * This format is taken from hammer blockmap.
 156          */
 157         printf("Stripped big-block ");
 158         if (VerboseOpt) {
 159                 printf("%016jx zone=%-2d vol=%-3d L1#=%-6d L2#=%-6d L1=%-7lu L2=%-7lu\n",
 160                         offset,
 161                         zone,
 162                         HAMMER_VOL_DECODE(offset),
 163                         HAMMER_BLOCKMAP_LAYER1_INDEX(offset),
 164                         HAMMER_BLOCKMAP_LAYER2_INDEX(offset),
 165                         HAMMER_BLOCKMAP_LAYER1_OFFSET(offset),
 166                         HAMMER_BLOCKMAP_LAYER2_OFFSET(offset));
 167         } else {
 168                 printf("%016jx\n", offset);
 169         }
 170
 171         for (i = 0; i < HAMMER_BIGBLOCK_SIZE; i += HAMMER_BUFSIZE) {
 172                 get_buffer_data(offset + i, &buffer, 1);
 173                 assert(buffer);
 174         }
 175 }
 176
 177 static
 178 void
 179 hammer_ask_yn(void)
 180 {
 181         volume_info_t volume;
 182 #define _HAMMER "HAMMER filesystem"
 183         char type[64];
 184         char label[64 + 4];
 185         int i;
 186
 187         volume = get_root_volume();
 188
 189         if (volume && volume->ondisk->vol_signature == HAMMER_FSBUF_VOLUME)
 190                 strcpy(type, _HAMMER);
 191         else
 192                 strcpy(type, "devices");
 193
 194         if (volume && volume->ondisk->vol_label[0]) {
 195                 snprintf(label, sizeof(label), " (%s)",
 196                         volume->ondisk->vol_label);
 197         } else {
 198                 strcpy(label, "");
 199         }
 200
 201         /*
 202          * This format is taken from hammer pfs-destroy.
 203          */
 204         printf("You have requested that %s%s be stripped", type, label);
 205         if (strcmp(type, _HAMMER))
 206                 printf(", but %s may not be %s volumes\n", type, _HAMMER);
 207         else
 208                 printf("\n");
 209
 210         printf("Do you really want to do this? [y/n] ");
 211         fflush(stdout);
 212         if (getyn() == 0) {
 213                 errx(1, "No action taken");
 214                 /* not reached */
 215         }
 216
 217         if (strcmp(type, _HAMMER)) {
 218                 printf("Are you absolutely sure you want to do this? [y/n] ");
 219                 fflush(stdout);
 220                 if (getyn() == 0) {
 221                         errx(1, "No action taken");
 222                         /* not reached */
 223                 }
 224         }
 225
 226         printf("Stripping %s%s", type, label);
 227
 228         if (DebugOpt) {
 229                 printf("\n");
 230         } else {
 231                 printf(" in");
 232                 for (i = 5; i; --i) {
 233                         printf(" %d", i);
 234                         fflush(stdout);
 235                         sleep(1);
 236                 }
 237                 printf(".. starting destruction pass\n");
 238         }
 239 }