]> git.sesse.net Git - bcachefs-tools-debian/blobdiff - bcache.c
Add multiple bucket_sizes to make-bcache
[bcachefs-tools-debian] / bcache.c
index 3ec068955c3343565111312cf896dcf6dd0aac68..7e0616492a56ac010b1d3405af65039ba90830aa 100644 (file)
--- a/bcache.c
+++ b/bcache.c
@@ -5,7 +5,19 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <stdint.h>
+#include <fcntl.h>
+#include <inttypes.h>
+#include <getopt.h>
+#include <limits.h>
+#include <linux/fs.h>
+#include <stdbool.h>
+#include <string.h>
+#include <sys/ioctl.h>
+#include <sys/types.h>
+#include <sys/stat.h>
 #include <unistd.h>
+#include <uuid/uuid.h>
+#include <blkid.h>
 
 #include "bcache.h"
 
@@ -117,6 +129,95 @@ void print_string_list(const char * const list[], size_t selected)
        }
 }
 
+/*
+ * This is the CRC-32C table
+ * Generated with:
+ * width = 32 bits
+ * poly = 0x1EDC6F41
+ * reflect input bytes = true
+ * reflect output bytes = true
+ */
+
+static const u32 crc32c_table[256] = {
+       0x00000000L, 0xF26B8303L, 0xE13B70F7L, 0x1350F3F4L,
+       0xC79A971FL, 0x35F1141CL, 0x26A1E7E8L, 0xD4CA64EBL,
+       0x8AD958CFL, 0x78B2DBCCL, 0x6BE22838L, 0x9989AB3BL,
+       0x4D43CFD0L, 0xBF284CD3L, 0xAC78BF27L, 0x5E133C24L,
+       0x105EC76FL, 0xE235446CL, 0xF165B798L, 0x030E349BL,
+       0xD7C45070L, 0x25AFD373L, 0x36FF2087L, 0xC494A384L,
+       0x9A879FA0L, 0x68EC1CA3L, 0x7BBCEF57L, 0x89D76C54L,
+       0x5D1D08BFL, 0xAF768BBCL, 0xBC267848L, 0x4E4DFB4BL,
+       0x20BD8EDEL, 0xD2D60DDDL, 0xC186FE29L, 0x33ED7D2AL,
+       0xE72719C1L, 0x154C9AC2L, 0x061C6936L, 0xF477EA35L,
+       0xAA64D611L, 0x580F5512L, 0x4B5FA6E6L, 0xB93425E5L,
+       0x6DFE410EL, 0x9F95C20DL, 0x8CC531F9L, 0x7EAEB2FAL,
+       0x30E349B1L, 0xC288CAB2L, 0xD1D83946L, 0x23B3BA45L,
+       0xF779DEAEL, 0x05125DADL, 0x1642AE59L, 0xE4292D5AL,
+       0xBA3A117EL, 0x4851927DL, 0x5B016189L, 0xA96AE28AL,
+       0x7DA08661L, 0x8FCB0562L, 0x9C9BF696L, 0x6EF07595L,
+       0x417B1DBCL, 0xB3109EBFL, 0xA0406D4BL, 0x522BEE48L,
+       0x86E18AA3L, 0x748A09A0L, 0x67DAFA54L, 0x95B17957L,
+       0xCBA24573L, 0x39C9C670L, 0x2A993584L, 0xD8F2B687L,
+       0x0C38D26CL, 0xFE53516FL, 0xED03A29BL, 0x1F682198L,
+       0x5125DAD3L, 0xA34E59D0L, 0xB01EAA24L, 0x42752927L,
+       0x96BF4DCCL, 0x64D4CECFL, 0x77843D3BL, 0x85EFBE38L,
+       0xDBFC821CL, 0x2997011FL, 0x3AC7F2EBL, 0xC8AC71E8L,
+       0x1C661503L, 0xEE0D9600L, 0xFD5D65F4L, 0x0F36E6F7L,
+       0x61C69362L, 0x93AD1061L, 0x80FDE395L, 0x72966096L,
+       0xA65C047DL, 0x5437877EL, 0x4767748AL, 0xB50CF789L,
+       0xEB1FCBADL, 0x197448AEL, 0x0A24BB5AL, 0xF84F3859L,
+       0x2C855CB2L, 0xDEEEDFB1L, 0xCDBE2C45L, 0x3FD5AF46L,
+       0x7198540DL, 0x83F3D70EL, 0x90A324FAL, 0x62C8A7F9L,
+       0xB602C312L, 0x44694011L, 0x5739B3E5L, 0xA55230E6L,
+       0xFB410CC2L, 0x092A8FC1L, 0x1A7A7C35L, 0xE811FF36L,
+       0x3CDB9BDDL, 0xCEB018DEL, 0xDDE0EB2AL, 0x2F8B6829L,
+       0x82F63B78L, 0x709DB87BL, 0x63CD4B8FL, 0x91A6C88CL,
+       0x456CAC67L, 0xB7072F64L, 0xA457DC90L, 0x563C5F93L,
+       0x082F63B7L, 0xFA44E0B4L, 0xE9141340L, 0x1B7F9043L,
+       0xCFB5F4A8L, 0x3DDE77ABL, 0x2E8E845FL, 0xDCE5075CL,
+       0x92A8FC17L, 0x60C37F14L, 0x73938CE0L, 0x81F80FE3L,
+       0x55326B08L, 0xA759E80BL, 0xB4091BFFL, 0x466298FCL,
+       0x1871A4D8L, 0xEA1A27DBL, 0xF94AD42FL, 0x0B21572CL,
+       0xDFEB33C7L, 0x2D80B0C4L, 0x3ED04330L, 0xCCBBC033L,
+       0xA24BB5A6L, 0x502036A5L, 0x4370C551L, 0xB11B4652L,
+       0x65D122B9L, 0x97BAA1BAL, 0x84EA524EL, 0x7681D14DL,
+       0x2892ED69L, 0xDAF96E6AL, 0xC9A99D9EL, 0x3BC21E9DL,
+       0xEF087A76L, 0x1D63F975L, 0x0E330A81L, 0xFC588982L,
+       0xB21572C9L, 0x407EF1CAL, 0x532E023EL, 0xA145813DL,
+       0x758FE5D6L, 0x87E466D5L, 0x94B49521L, 0x66DF1622L,
+       0x38CC2A06L, 0xCAA7A905L, 0xD9F75AF1L, 0x2B9CD9F2L,
+       0xFF56BD19L, 0x0D3D3E1AL, 0x1E6DCDEEL, 0xEC064EEDL,
+       0xC38D26C4L, 0x31E6A5C7L, 0x22B65633L, 0xD0DDD530L,
+       0x0417B1DBL, 0xF67C32D8L, 0xE52CC12CL, 0x1747422FL,
+       0x49547E0BL, 0xBB3FFD08L, 0xA86F0EFCL, 0x5A048DFFL,
+       0x8ECEE914L, 0x7CA56A17L, 0x6FF599E3L, 0x9D9E1AE0L,
+       0xD3D3E1ABL, 0x21B862A8L, 0x32E8915CL, 0xC083125FL,
+       0x144976B4L, 0xE622F5B7L, 0xF5720643L, 0x07198540L,
+       0x590AB964L, 0xAB613A67L, 0xB831C993L, 0x4A5A4A90L,
+       0x9E902E7BL, 0x6CFBAD78L, 0x7FAB5E8CL, 0x8DC0DD8FL,
+       0xE330A81AL, 0x115B2B19L, 0x020BD8EDL, 0xF0605BEEL,
+       0x24AA3F05L, 0xD6C1BC06L, 0xC5914FF2L, 0x37FACCF1L,
+       0x69E9F0D5L, 0x9B8273D6L, 0x88D28022L, 0x7AB90321L,
+       0xAE7367CAL, 0x5C18E4C9L, 0x4F48173DL, 0xBD23943EL,
+       0xF36E6F75L, 0x0105EC76L, 0x12551F82L, 0xE03E9C81L,
+       0x34F4F86AL, 0xC69F7B69L, 0xD5CF889DL, 0x27A40B9EL,
+       0x79B737BAL, 0x8BDCB4B9L, 0x988C474DL, 0x6AE7C44EL,
+       0xBE2DA0A5L, 0x4C4623A6L, 0x5F16D052L, 0xAD7D5351L
+};
+
+/*
+ * Steps through buffer one byte at at time, calculates reflected
+ * crc using table.
+ */
+
+static u32 crc32c(u32 crc, unsigned char const *data, size_t length)
+{
+       while (length--)
+               crc =
+                   crc32c_table[(crc ^ *data++) & 0xFFL] ^ (crc >> 8);
+       return crc;
+}
+
 /*
  * Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group (Any
  * use permitted, subject to terms of PostgreSQL license; see.)
@@ -244,6 +345,8 @@ static uint64_t bch_checksum_update(unsigned type, uint64_t crc, const void *dat
        switch (type) {
        case BCH_CSUM_NONE:
                return 0;
+       case BCH_CSUM_CRC32C:
+               return crc32c(crc, data, len);
        case BCH_CSUM_CRC64:
                return bch_crc64_update(crc, data, len);
        default:
@@ -260,3 +363,485 @@ uint64_t bch_checksum(unsigned type, const void *data, size_t len)
 
        return crc ^ 0xffffffffffffffffULL;
 }
+
+uint64_t getblocks(int fd)
+{
+       uint64_t ret;
+       struct stat statbuf;
+       if (fstat(fd, &statbuf)) {
+               perror("stat error\n");
+               exit(EXIT_FAILURE);
+       }
+       ret = statbuf.st_size / 512;
+       if (S_ISBLK(statbuf.st_mode))
+               if (ioctl(fd, BLKGETSIZE, &ret)) {
+                       perror("ioctl error");
+                       exit(EXIT_FAILURE);
+               }
+       return ret;
+}
+
+uint64_t hatoi(const char *s)
+{
+       char *e;
+       long long i = strtoll(s, &e, 10);
+       switch (*e) {
+               case 't':
+               case 'T':
+                       i *= 1024;
+               case 'g':
+               case 'G':
+                       i *= 1024;
+               case 'm':
+               case 'M':
+                       i *= 1024;
+               case 'k':
+               case 'K':
+                       i *= 1024;
+       }
+       return i;
+}
+
+unsigned hatoi_validate(const char *s, const char *msg)
+{
+       uint64_t v = hatoi(s);
+
+       if (v & (v - 1)) {
+               fprintf(stderr, "%s must be a power of two\n", msg);
+               exit(EXIT_FAILURE);
+       }
+
+       v /= 512;
+
+       if (v > USHRT_MAX) {
+               fprintf(stderr, "%s too large\n", msg);
+               exit(EXIT_FAILURE);
+       }
+
+       if (!v) {
+               fprintf(stderr, "%s too small\n", msg);
+               exit(EXIT_FAILURE);
+       }
+
+       return v;
+}
+
+static void do_write_sb(int fd, struct cache_sb *sb)
+{
+       char zeroes[SB_START] = {0};
+       size_t bytes = ((void *) bset_bkey_last(sb)) - (void *) sb;
+
+       /* Zero start of disk */
+       if (pwrite(fd, zeroes, SB_START, 0) != SB_START) {
+               perror("write error\n");
+               exit(EXIT_FAILURE);
+       }
+       /* Write superblock */
+       if (pwrite(fd, sb, bytes, SB_START) != bytes) {
+               perror("write error\n");
+               exit(EXIT_FAILURE);
+       }
+
+       fsync(fd);
+       close(fd);
+}
+
+void write_backingdev_sb(int fd, unsigned block_size, unsigned *bucket_sizes,
+                               bool writeback, uint64_t data_offset,
+                               const char *label,
+                               uuid_le set_uuid)
+{
+       char uuid_str[40], set_uuid_str[40];
+       struct cache_sb sb;
+
+       memset(&sb, 0, sizeof(struct cache_sb));
+
+       sb.offset       = SB_SECTOR;
+       sb.version      = BCACHE_SB_VERSION_BDEV;
+       sb.magic        = BCACHE_MAGIC;
+       uuid_generate(sb.uuid.b);
+       sb.set_uuid     = set_uuid;
+       sb.bucket_size  = bucket_sizes[0];
+       sb.block_size   = block_size;
+
+       uuid_unparse(sb.uuid.b, uuid_str);
+       uuid_unparse(sb.set_uuid.b, set_uuid_str);
+       if (label)
+               memcpy(sb.label, label, SB_LABEL_SIZE);
+
+       SET_BDEV_CACHE_MODE(&sb, writeback
+                           ? CACHE_MODE_WRITEBACK
+                           : CACHE_MODE_WRITETHROUGH);
+
+       if (data_offset != BDEV_DATA_START_DEFAULT) {
+               sb.version = BCACHE_SB_VERSION_BDEV_WITH_OFFSET;
+               sb.data_offset = data_offset;
+       }
+
+       sb.csum = csum_set(&sb, BCH_CSUM_CRC64);
+
+       printf("UUID:                   %s\n"
+              "Set UUID:               %s\n"
+              "version:                %u\n"
+              "block_size:             %u\n"
+              "data_offset:            %ju\n",
+              uuid_str, set_uuid_str,
+              (unsigned) sb.version,
+              sb.block_size,
+              data_offset);
+
+       do_write_sb(fd, &sb);
+}
+
+int dev_open(const char *dev, bool wipe_bcache)
+{
+       struct cache_sb sb;
+       blkid_probe pr;
+       int fd;
+
+       if ((fd = open(dev, O_RDWR|O_EXCL)) == -1) {
+               fprintf(stderr, "Can't open dev %s: %s\n", dev, strerror(errno));
+               exit(EXIT_FAILURE);
+       }
+
+       if (pread(fd, &sb, sizeof(sb), SB_START) != sizeof(sb))
+               exit(EXIT_FAILURE);
+
+       if (!memcmp(&sb.magic, &BCACHE_MAGIC, 16) && !wipe_bcache) {
+               fprintf(stderr, "Already a bcache device on %s, "
+                       "overwrite with --wipe-bcache\n", dev);
+               exit(EXIT_FAILURE);
+       }
+
+       if (!(pr = blkid_new_probe()))
+               exit(EXIT_FAILURE);
+       if (blkid_probe_set_device(pr, fd, 0, 0))
+               exit(EXIT_FAILURE);
+       /* enable ptable probing; superblock probing is enabled by default */
+       if (blkid_probe_enable_partitions(pr, true))
+               exit(EXIT_FAILURE);
+       if (!blkid_do_probe(pr)) {
+               /* XXX wipefs doesn't know how to remove partition tables */
+               fprintf(stderr, "Device %s already has a non-bcache superblock, "
+                               "remove it using wipefs and wipefs -a\n", dev);
+               exit(EXIT_FAILURE);
+       }
+
+       return fd;
+}
+
+static unsigned min_bucket_size(int num_bucket_sizes, unsigned *bucket_sizes)
+{
+       int i;
+       unsigned min = bucket_sizes[0];
+
+       for (i = 0; i < num_bucket_sizes; i++)
+               min = bucket_sizes[i] < min ? bucket_sizes[i] : min;
+
+       return min;
+}
+
+static unsigned node_size(unsigned bucket_size) {
+
+       if (bucket_size <= 256)
+               return bucket_size;
+       else if (bucket_size <= 512)
+               return bucket_size / 2;
+       else
+               return bucket_size / 4;
+}
+
+void write_cache_sbs(int *fds, struct cache_sb *sb,
+                           unsigned block_size, unsigned *bucket_sizes,
+                               int num_bucket_sizes)
+{
+       char uuid_str[40], set_uuid_str[40];
+       size_t i;
+       unsigned min_size = min_bucket_size(num_bucket_sizes, bucket_sizes);
+
+       sb->offset      = SB_SECTOR;
+       sb->version     = BCACHE_SB_VERSION_CDEV_V3;
+       sb->magic       = BCACHE_MAGIC;
+       sb->block_size  = block_size;
+       sb->keys        = bch_journal_buckets_offset(sb);
+
+       /*
+        * don't have a userspace crc32c implementation handy, just always use
+        * crc64
+        */
+       SET_CACHE_SB_CSUM_TYPE(sb, BCH_CSUM_CRC64);
+
+       for (i = 0; i < sb->nr_in_set; i++) {
+               struct cache_member *m = sb->members + i;
+
+               if (num_bucket_sizes <= 1)
+                       sb->bucket_size = bucket_sizes[0];
+               else
+                       sb->bucket_size = bucket_sizes[i];
+               SET_CACHE_BTREE_NODE_SIZE(sb, node_size(min_size));
+
+               sb->uuid = m->uuid;
+               sb->nbuckets            = getblocks(fds[i]) / sb->bucket_size;
+               sb->nr_this_dev         = i;
+               sb->first_bucket        = (23 / sb->bucket_size) + 1;
+
+               if (sb->nbuckets < 1 << 7) {
+                       fprintf(stderr, "Not enough buckets: %llu, need %u\n",
+                               sb->nbuckets, 1 << 7);
+                       exit(EXIT_FAILURE);
+               }
+
+               sb->csum = csum_set(sb, CACHE_SB_CSUM_TYPE(sb));
+
+               uuid_unparse(sb->uuid.b, uuid_str);
+               uuid_unparse(sb->set_uuid.b, set_uuid_str);
+               printf("UUID:                   %s\n"
+                      "Set UUID:               %s\n"
+                      "version:                %u\n"
+                      "nbuckets:               %llu\n"
+                      "block_size:             %u\n"
+                      "bucket_size:            %u\n"
+                      "nr_in_set:              %u\n"
+                      "nr_this_dev:            %u\n"
+                      "first_bucket:           %u\n",
+                      uuid_str, set_uuid_str,
+                      (unsigned) sb->version,
+                      sb->nbuckets,
+                      sb->block_size,
+                      sb->bucket_size,
+                      sb->nr_in_set,
+                      sb->nr_this_dev,
+                      sb->first_bucket);
+
+               do_write_sb(fds[i], sb);
+       }
+}
+
+void next_cache_device(struct cache_sb *sb,
+                             unsigned replication_set,
+                             unsigned tier,
+                             unsigned replacement_policy,
+                             bool discard)
+{
+       struct cache_member *m = sb->members + sb->nr_in_set;
+
+       SET_CACHE_REPLICATION_SET(m, replication_set);
+       SET_CACHE_TIER(m, tier);
+       SET_CACHE_REPLACEMENT(m, replacement_policy);
+       SET_CACHE_DISCARD(m, discard);
+       uuid_generate(m->uuid.b);
+
+       sb->nr_in_set++;
+}
+
+unsigned get_blocksize(const char *path)
+{
+       struct stat statbuf;
+
+       if (stat(path, &statbuf)) {
+               fprintf(stderr, "Error statting %s: %s\n",
+                       path, strerror(errno));
+               exit(EXIT_FAILURE);
+       }
+
+       if (S_ISBLK(statbuf.st_mode)) {
+               /* check IO limits:
+                * BLKALIGNOFF: alignment_offset
+                * BLKPBSZGET: physical_block_size
+                * BLKSSZGET: logical_block_size
+                * BLKIOMIN: minimum_io_size
+                * BLKIOOPT: optimal_io_size
+                *
+                * It may be tempting to use physical_block_size,
+                * or even minimum_io_size.
+                * But to be as transparent as possible,
+                * we want to use logical_block_size.
+                */
+               unsigned int logical_block_size;
+               int fd = open(path, O_RDONLY);
+
+               if (fd < 0) {
+                       fprintf(stderr, "open(%s) failed: %m\n", path);
+                       exit(EXIT_FAILURE);
+               }
+               if (ioctl(fd, BLKSSZGET, &logical_block_size)) {
+                       fprintf(stderr, "ioctl(%s, BLKSSZGET) failed: %m\n", path);
+                       exit(EXIT_FAILURE);
+               }
+               close(fd);
+               return logical_block_size / 512;
+
+       }
+       /* else: not a block device.
+        * Why would we even want to write a bcache super block there? */
+
+       return statbuf.st_blksize / 512;
+}
+
+long strtoul_or_die(const char *p, size_t max, const char *msg)
+{
+       errno = 0;
+       long v = strtol(optarg, NULL, 10);
+       if (errno || v < 0 || v >= max) {
+               fprintf(stderr, "Invalid %s %zi\n", msg, v);
+               exit(EXIT_FAILURE);
+       }
+
+       return v;
+}
+
+static void print_encode(char *in)
+{
+    char *pos;
+       for (pos = in; *pos; pos++)
+               if (isalnum(*pos) || strchr(".-_", *pos))
+                       putchar(*pos);
+               else
+                       printf("%%%x", *pos);
+}
+
+static void show_super_common(struct cache_sb *sb, bool force_csum)
+{
+       char uuid[40];
+       char label[SB_LABEL_SIZE + 1];
+       uint64_t expected_csum;
+
+       printf("sb.magic\t\t");
+       if (!memcmp(&sb->magic, &BCACHE_MAGIC, sizeof(sb->magic))) {
+               printf("ok\n");
+       } else {
+               printf("bad magic\n");
+               fprintf(stderr, "Invalid superblock (bad magic)\n");
+               exit(2);
+       }
+
+       printf("sb.first_sector\t\t%ju", (uint64_t) sb->offset);
+       if (sb->offset == SB_SECTOR) {
+               printf(" [match]\n");
+       } else {
+               printf(" [expected %ds]\n", SB_SECTOR);
+               fprintf(stderr, "Invalid superblock (bad sector)\n");
+               exit(2);
+       }
+
+       printf("sb.csum\t\t\t%ju", (uint64_t) sb->csum);
+       expected_csum = csum_set(sb,
+                                sb->version < BCACHE_SB_VERSION_CDEV_V3
+                                ? BCH_CSUM_CRC64
+                                : CACHE_SB_CSUM_TYPE(sb));
+       if (sb->csum == expected_csum) {
+               printf(" [match]\n");
+       } else {
+               printf(" [expected %" PRIX64 "]\n", expected_csum);
+               if (!force_csum) {
+                       fprintf(stderr, "Corrupt superblock (bad csum)\n");
+                       exit(2);
+               }
+       }
+
+       printf("sb.version\t\t%ju", (uint64_t) sb->version);
+       switch (sb->version) {
+               // These are handled the same by the kernel
+               case BCACHE_SB_VERSION_CDEV:
+               case BCACHE_SB_VERSION_CDEV_WITH_UUID:
+                       printf(" [cache device]\n");
+                       break;
+
+               // The second adds data offset support
+               case BCACHE_SB_VERSION_BDEV:
+               case BCACHE_SB_VERSION_BDEV_WITH_OFFSET:
+                       printf(" [backing device]\n");
+                       break;
+
+               default:
+                       printf(" [unknown]\n");
+                       // exit code?
+                       exit(EXIT_SUCCESS);
+       }
+
+       putchar('\n');
+
+       strncpy(label, (char *) sb->label, SB_LABEL_SIZE);
+       label[SB_LABEL_SIZE] = '\0';
+       printf("dev.label\t\t");
+       if (*label)
+               print_encode(label);
+       else
+               printf("(empty)");
+       putchar('\n');
+
+       uuid_unparse(sb->uuid.b, uuid);
+       printf("dev.uuid\t\t%s\n", uuid);
+
+       uuid_unparse(sb->set_uuid.b, uuid);
+       printf("cset.uuid\t\t%s\n", uuid);
+}
+
+void show_super_backingdev(struct cache_sb *sb, bool force_csum)
+{
+       uint64_t first_sector;
+
+       show_super_common(sb, force_csum);
+
+       if (sb->version == BCACHE_SB_VERSION_BDEV) {
+               first_sector = BDEV_DATA_START_DEFAULT;
+       } else {
+               if (sb->keys == 1 || sb->d[0]) {
+                       fprintf(stderr,
+                               "Possible experimental format detected, bailing\n");
+                       exit(3);
+               }
+               first_sector = sb->data_offset;
+       }
+
+       printf("dev.data.first_sector\t%ju\n"
+              "dev.data.cache_mode\t%s"
+              "dev.data.cache_state\t%s\n",
+              first_sector,
+              bdev_cache_mode[BDEV_CACHE_MODE(sb)],
+              bdev_state[BDEV_STATE(sb)]);
+}
+
+void show_cache_member(struct cache_sb *sb, unsigned i)
+{
+       struct cache_member *m = ((struct cache_member *) sb->d) + i;
+
+       printf("cache.state\t%s\n",             cache_state[CACHE_STATE(m)]);
+       printf("cache.tier\t%llu\n",            CACHE_TIER(m));
+
+       printf("cache.replication_set\t%llu\n", CACHE_REPLICATION_SET(m));
+       printf("cache.cur_meta_replicas\t%llu\n", REPLICATION_SET_CUR_META_REPLICAS(m));
+       printf("cache.cur_data_replicas\t%llu\n", REPLICATION_SET_CUR_DATA_REPLICAS(m));
+
+       printf("cache.has_metadata\t%llu\n",    CACHE_HAS_METADATA(m));
+       printf("cache.has_data\t%llu\n",        CACHE_HAS_DATA(m));
+
+       printf("cache.replacement\t%s\n",       replacement_policies[CACHE_REPLACEMENT(m)]);
+       printf("cache.discard\t%llu\n",         CACHE_DISCARD(m));
+}
+
+void show_super_cache(struct cache_sb *sb, bool force_csum)
+{
+       show_super_common(sb, force_csum);
+
+       printf("dev.sectors_per_block\t%u\n"
+              "dev.sectors_per_bucket\t%u\n",
+              sb->block_size,
+              sb->bucket_size);
+
+       // total_sectors includes the superblock;
+       printf("dev.cache.first_sector\t%u\n"
+              "dev.cache.cache_sectors\t%llu\n"
+              "dev.cache.total_sectors\t%llu\n"
+              "dev.cache.ordered\t%s\n"
+              "dev.cache.pos\t\t%u\n"
+              "dev.cache.setsize\t\t%u\n",
+              sb->bucket_size * sb->first_bucket,
+              sb->bucket_size * (sb->nbuckets - sb->first_bucket),
+              sb->bucket_size * sb->nbuckets,
+              CACHE_SYNC(sb) ? "yes" : "no",
+              sb->nr_this_dev,
+              sb->nr_in_set);
+
+       show_cache_member(sb, sb->nr_this_dev);
+}