root/sbin/newfs_hammer2/mkfs_hammer2.c
/*
 * Copyright (c) 2022 Tomohiro Kusumi <tkusumi@netbsd.org>
 * Copyright (c) 2011-2022 The DragonFly Project.  All rights reserved.
 *
 * This code is derived from software contributed to The DragonFly Project
 * by Matthew Dillon <dillon@dragonflybsd.org>
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 * 3. Neither the name of The DragonFly Project nor the names of its
 *    contributors may be used to endorse or promote products derived
 *    from this software without specific, prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include <sys/types.h>
#include <sys/time.h>
#include <sys/sysctl.h>

#include <stdio.h>
#include <stdlib.h>
#include <stddef.h>
#include <stdint.h>
#include <unistd.h>
#include <string.h>
#include <fcntl.h>
#include <assert.h>
#include <err.h>
#include <uuid.h>

#include <vfs/hammer2/hammer2_disk.h>
#include <vfs/hammer2/hammer2_xxhash.h>

#include "mkfs_hammer2.h"
#include "hammer2_subs.h"

static uint64_t nowtime(void);
static int blkrefary_cmp(const void *b1, const void *b2);
static void alloc_direct(hammer2_off_t *basep, hammer2_blockref_t *bref,
                                size_t bytes);

static int
get_hammer2_version(void)
{
        int version = HAMMER2_VOL_VERSION_DEFAULT;
        size_t olen = sizeof(version);

        if (sysctlbyname("vfs.hammer2.supported_version",
                         &version, &olen, NULL, 0) == 0) {
                if (version >= HAMMER2_VOL_VERSION_WIP) {
                        version = HAMMER2_VOL_VERSION_WIP - 1;
                        fprintf(stderr,
                                "newfs_hammer2: WARNING: HAMMER2 VFS "
                                "supports higher version than I "
                                "understand.\n"
                                "Using default version %d\n",
                                version);
                }
        } else {
                fprintf(stderr,
                        "newfs_hammer2: WARNING: HAMMER2 VFS not "
                        "loaded, cannot get version info.\n"
                        "Using default version %d\n",
                        version);
        }
        return(version);
}

void
hammer2_mkfs_init(hammer2_mkfs_options_t *opt)
{
        uint32_t status;

        memset(opt, 0, sizeof(*opt));

        opt->Hammer2Version = get_hammer2_version();
        opt->Label[opt->NLabels++] = strdup("LOCAL");
        opt->CompType = HAMMER2_COMP_DEFAULT; /* LZ4 */
        opt->CheckType = HAMMER2_CHECK_DEFAULT; /* xxhash64 */
        opt->DefaultLabelType = HAMMER2_LABEL_NONE;

        /*
         * Generate a filesystem id and lookup the filesystem type
         */
        srandomdev();
        uuid_create(&opt->Hammer2_VolFSID, NULL);
        uuid_create(&opt->Hammer2_SupCLID, NULL);
        uuid_create(&opt->Hammer2_SupFSID, NULL);
        uuid_from_string(HAMMER2_UUID_STRING, &opt->Hammer2_FSType, &status);
        /*uuid_name_lookup(&Hammer2_FSType, "DragonFly HAMMER2", &status);*/
        if (status != uuid_s_ok) {
                errx(1, "uuids file does not have the DragonFly "
                        "HAMMER2 filesystem type");
        }
}

void
hammer2_mkfs_cleanup(hammer2_mkfs_options_t *opt)
{
        int i;

        for (i = 0; i < opt->NLabels; i++)
                free(opt->Label[i]);
}

static void
adjust_options(hammer2_ondisk_t *fso, hammer2_mkfs_options_t *opt)
{
        /*
         * Adjust Label[] and NLabels.
         */
        switch (opt->DefaultLabelType) {
        case HAMMER2_LABEL_BOOT:
                opt->Label[opt->NLabels++] = strdup("BOOT");
                break;
        case HAMMER2_LABEL_ROOT:
                opt->Label[opt->NLabels++] = strdup("ROOT");
                break;
        case HAMMER2_LABEL_DATA:
                opt->Label[opt->NLabels++] = strdup("DATA");
                break;
        case HAMMER2_LABEL_NONE:
                /* nothing to do */
                break;
        default:
                assert(0);
                break;
        }

        /*
         * Calculate defaults for the boot area size and round to the
         * volume alignment boundary.
         *
         * NOTE: These areas are currently not used for booting but are
         *       reserved for future filesystem expansion.
         */
        hammer2_off_t BootAreaSize = opt->BootAreaSize;
        if (BootAreaSize == 0) {
                BootAreaSize = HAMMER2_BOOT_NOM_BYTES;
                while (BootAreaSize > fso->total_size / 20)
                        BootAreaSize >>= 1;
                if (BootAreaSize < HAMMER2_BOOT_MIN_BYTES)
                        BootAreaSize = HAMMER2_BOOT_MIN_BYTES;
        } else if (BootAreaSize < HAMMER2_BOOT_MIN_BYTES) {
                BootAreaSize = HAMMER2_BOOT_MIN_BYTES;
        }
        BootAreaSize = (BootAreaSize + HAMMER2_VOLUME_ALIGNMASK64) &
                        ~HAMMER2_VOLUME_ALIGNMASK64;
        opt->BootAreaSize = BootAreaSize;

        /*
         * Calculate defaults for the aux area size and round to the
         * volume alignment boundary.
         *
         * NOTE: These areas are currently not used for logging but are
         *       reserved for future filesystem expansion.
         */
        hammer2_off_t AuxAreaSize = opt->AuxAreaSize;
        if (AuxAreaSize == 0) {
                AuxAreaSize = HAMMER2_AUX_NOM_BYTES;
                while (AuxAreaSize > fso->total_size / 20)
                        AuxAreaSize >>= 1;
                if (AuxAreaSize < HAMMER2_AUX_MIN_BYTES)
                        AuxAreaSize = HAMMER2_AUX_MIN_BYTES;
        } else if (AuxAreaSize < HAMMER2_AUX_MIN_BYTES) {
                AuxAreaSize = HAMMER2_AUX_MIN_BYTES;
        }
        AuxAreaSize = (AuxAreaSize + HAMMER2_VOLUME_ALIGNMASK64) &
                       ~HAMMER2_VOLUME_ALIGNMASK64;
        opt->AuxAreaSize = AuxAreaSize;
}

/*
 * Convert a string to a 64 bit signed integer with various requirements.
 */
int64_t
getsize(const char *str, int64_t minval, int64_t maxval, int powerof2)
{
        int64_t val;
        char *ptr;

        val = strtoll(str, &ptr, 0);
        switch(*ptr) {
        case 't':
        case 'T':
                val *= 1024;
                /* fall through */
        case 'g':
        case 'G':
                val *= 1024;
                /* fall through */
        case 'm':
        case 'M':
                val *= 1024;
                /* fall through */
        case 'k':
        case 'K':
                val *= 1024;
                break;
        default:
                errx(1, "Unknown suffix in number '%s'", str);
                /* not reached */
        }
        if (ptr[1]) {
                errx(1, "Unknown suffix in number '%s'", str);
                /* not reached */
        }
        if (val < minval) {
                errx(1, "Value too small: %s, min is %s",
                     str, sizetostr(minval));
                /* not reached */
        }
        if (val > maxval) {
                errx(1, "Value too large: %s, max is %s",
                     str, sizetostr(maxval));
                /* not reached */
        }
        if ((powerof2 & 1) && (val ^ (val - 1)) != ((val << 1) - 1)) {
                errx(1, "Value not power of 2: %s", str);
                /* not reached */
        }
        if ((powerof2 & 2) && (val & HAMMER2_NEWFS_ALIGNMASK)) {
                errx(1, "Value not an integral multiple of %dK: %s",
                     HAMMER2_NEWFS_ALIGN / 1024, str);
                /* not reached */
        }
        return(val);
}

static uint64_t
nowtime(void)
{
        struct timeval tv;
        uint64_t xtime;

        gettimeofday(&tv, NULL);
        xtime = tv.tv_sec * 1000000LL + tv.tv_usec;
        return(xtime);
}

static hammer2_off_t
format_hammer2_misc(hammer2_volume_t *vol, hammer2_mkfs_options_t *opt,
                    hammer2_off_t boot_base, hammer2_off_t aux_base)
{
        char *buf = malloc(HAMMER2_PBUFSIZE);
        hammer2_off_t alloc_base = aux_base + opt->AuxAreaSize;
        hammer2_off_t tmp_base;
        size_t n;
        int i;

        /*
         * Clear the entire 4MB reserve for the first 2G zone.
         */
        bzero(buf, HAMMER2_PBUFSIZE);
        tmp_base = 0;
        for (i = 0; i < HAMMER2_ZONE_BLOCKS_SEG; ++i) {
                n = pwrite(vol->fd, buf, HAMMER2_PBUFSIZE, tmp_base);
                if (n != HAMMER2_PBUFSIZE) {
                        perror("write");
                        exit(1);
                }
                tmp_base += HAMMER2_PBUFSIZE;
        }

        /*
         * Make sure alloc_base won't cross the reserved area at the
         * beginning of each 1GB.
         *
         * Reserve space for the super-root inode and the root inode.
         * Make sure they are in the same 64K block to simplify our code.
         */
        assert((alloc_base & HAMMER2_PBUFMASK) == 0);
        assert(alloc_base < HAMMER2_FREEMAP_LEVEL1_SIZE);

        /*
         * Clear the boot/aux area.
         */
        for (tmp_base = boot_base; tmp_base < alloc_base;
             tmp_base += HAMMER2_PBUFSIZE) {
                n = pwrite(vol->fd, buf, HAMMER2_PBUFSIZE, tmp_base);
                if (n != HAMMER2_PBUFSIZE) {
                        perror("write (boot/aux)");
                        exit(1);
                }
        }

        free(buf);
        return(alloc_base);
}

static hammer2_off_t
format_hammer2_inode(hammer2_volume_t *vol, hammer2_mkfs_options_t *opt,
                     hammer2_blockref_t *sroot_blockrefp,
                     hammer2_off_t alloc_base)
{
        char *buf = malloc(HAMMER2_PBUFSIZE);
        hammer2_inode_data_t *rawip;
        hammer2_blockref_t sroot_blockref;
        hammer2_blockref_t root_blockref[MAXLABELS];
        uint64_t now;
        size_t n;
        int i;

        bzero(buf, HAMMER2_PBUFSIZE);
        bzero(&sroot_blockref, sizeof(sroot_blockref));
        bzero(root_blockref, sizeof(root_blockref));
        now = nowtime();
        alloc_base &= ~HAMMER2_PBUFMASK64;
        alloc_direct(&alloc_base, &sroot_blockref, HAMMER2_INODE_BYTES);

        for (i = 0; i < opt->NLabels; ++i) {
                uuid_create(&opt->Hammer2_PfsCLID[i], NULL);
                uuid_create(&opt->Hammer2_PfsFSID[i], NULL);

                alloc_direct(&alloc_base, &root_blockref[i],
                             HAMMER2_INODE_BYTES);
                assert(((sroot_blockref.data_off ^ root_blockref[i].data_off) &
                        ~HAMMER2_PBUFMASK64) == 0);

                /*
                 * Format the root directory inode, which is left empty.
                 */
                rawip = (void *)(buf + (HAMMER2_OFF_MASK_LO &
                                        root_blockref[i].data_off));
                rawip->meta.version = HAMMER2_INODE_VERSION_ONE;
                rawip->meta.ctime = now;
                rawip->meta.mtime = now;
                /* rawip->atime = now; NOT IMPL MUST BE ZERO */
                rawip->meta.btime = now;
                rawip->meta.type = HAMMER2_OBJTYPE_DIRECTORY;
                rawip->meta.mode = 0755;
                rawip->meta.inum = 1;   /* root inode, inumber 1 */
                rawip->meta.nlinks = 1; /* directory link count compat */

                rawip->meta.name_len = strlen(opt->Label[i]);
                bcopy(opt->Label[i], rawip->filename, rawip->meta.name_len);
                rawip->meta.name_key =
                                dirhash((char *)rawip->filename, rawip->meta.name_len);

                /*
                 * Compression mode and supported copyids.
                 *
                 * Do not allow compression when creating any "BOOT" label
                 * (pfs-create also does the same if the pfs is named "BOOT")
                 */
                if (strcasecmp(opt->Label[i], "BOOT") == 0) {
                        rawip->meta.comp_algo = HAMMER2_ENC_ALGO(
                                                    HAMMER2_COMP_AUTOZERO);
                        rawip->meta.check_algo = HAMMER2_ENC_ALGO(
                                                    HAMMER2_CHECK_XXHASH64);
                } else {
                        rawip->meta.comp_algo = HAMMER2_ENC_ALGO(
                                                    opt->CompType);
                        rawip->meta.check_algo = HAMMER2_ENC_ALGO(
                                                    opt->CheckType);
                }

                /*
                 * NOTE: We leave nmasters set to 0, which means that we
                 *       don't know how many masters there are.  The quorum
                 *       calculation will effectively be 1 ( 0 / 2 + 1 ).
                 */
                rawip->meta.pfs_clid = opt->Hammer2_PfsCLID[i];
                rawip->meta.pfs_fsid = opt->Hammer2_PfsFSID[i];
                rawip->meta.pfs_type = HAMMER2_PFSTYPE_MASTER;
                rawip->meta.op_flags |= HAMMER2_OPFLAG_PFSROOT;

                /* first allocatable inode number */
                rawip->meta.pfs_inum = 16;

                /* rawip->u.blockset is left empty */

                /*
                 * The root blockref will be stored in the super-root inode as
                 * one of the ~4 PFS root directories.  The copyid here is the
                 * actual copyid of the storage ref.
                 *
                 * The key field for a PFS root directory's blockref is
                 * essentially the name key for the entry.
                 */
                root_blockref[i].key = rawip->meta.name_key;
                root_blockref[i].copyid = HAMMER2_COPYID_LOCAL;
                root_blockref[i].keybits = 0;
                root_blockref[i].check.xxhash64.value =
                                XXH64(rawip, sizeof(*rawip), XXH_HAMMER2_SEED);
                root_blockref[i].type = HAMMER2_BREF_TYPE_INODE;
                root_blockref[i].methods =
                                HAMMER2_ENC_CHECK(HAMMER2_CHECK_XXHASH64) |
                                HAMMER2_ENC_COMP(HAMMER2_COMP_NONE);
                root_blockref[i].mirror_tid = 16;
                root_blockref[i].flags = HAMMER2_BREF_FLAG_PFSROOT;
        }

        /*
         * Format the super-root directory inode, giving it ~4 PFS root
         * directories (root_blockref).
         *
         * The superroot contains ~4 directories pointing at the PFS root
         * inodes (named via the label).  Inodes contain one blockset which
         * is fully associative so we can put the entry anywhere without
         * having to worry about the hash.  Use index 0.
         */
        rawip = (void *)(buf + (HAMMER2_OFF_MASK_LO & sroot_blockref.data_off));
        rawip->meta.version = HAMMER2_INODE_VERSION_ONE;
        rawip->meta.ctime = now;
        rawip->meta.mtime = now;
        /* rawip->meta.atime = now; NOT IMPL MUST BE ZERO */
        rawip->meta.btime = now;
        rawip->meta.type = HAMMER2_OBJTYPE_DIRECTORY;
        rawip->meta.mode = 0700;        /* super-root - root only */
        rawip->meta.inum = 0;           /* super root inode, inumber 0 */
        rawip->meta.nlinks = 2;         /* directory link count compat */

        rawip->meta.comp_algo = HAMMER2_ENC_ALGO(HAMMER2_COMP_AUTOZERO);
        rawip->meta.check_algo = HAMMER2_ENC_ALGO(HAMMER2_CHECK_XXHASH64);

        /*
         * The super-root is flagged as a PFS and typically given its own
         * random FSID, making it possible to mirror an entire HAMMER2 disk
         * snapshots and all if desired.  PFS ids are used to match up
         * mirror sources and targets and cluster copy sources and targets.
         *
         * (XXX whole-disk logical mirroring is not really supported in
         *  the first attempt because each PFS is in its own modify/mirror
         *  transaction id domain, so normal mechanics cannot cross a PFS
         *  boundary).
         */
        rawip->meta.pfs_clid = opt->Hammer2_SupCLID;
        rawip->meta.pfs_fsid = opt->Hammer2_SupFSID;
        rawip->meta.pfs_type = HAMMER2_PFSTYPE_SUPROOT;
        snprintf((char*)rawip->filename, sizeof(rawip->filename), "SUPROOT");
        rawip->meta.name_key = 0;
        rawip->meta.name_len = strlen((char*)rawip->filename);

        /* The super-root has an inode number of 0 */
        rawip->meta.pfs_inum = 0;

        /*
         * Currently newfs_hammer2 just throws the PFS inodes into the
         * top-level block table at the volume root and doesn't try to
         * create an indirect block, so we are limited to ~4 at filesystem
         * creation time.  More can be added after mounting.
         */
        qsort(root_blockref, opt->NLabels, sizeof(root_blockref[0]), blkrefary_cmp);
        for (i = 0; i < opt->NLabels; ++i)
                rawip->u.blockset.blockref[i] = root_blockref[i];

        /*
         * The sroot blockref will be stored in the volume header.
         */
        sroot_blockref.copyid = HAMMER2_COPYID_LOCAL;
        sroot_blockref.keybits = 0;
        sroot_blockref.check.xxhash64.value =
                                XXH64(rawip, sizeof(*rawip), XXH_HAMMER2_SEED);
        sroot_blockref.type = HAMMER2_BREF_TYPE_INODE;
        sroot_blockref.methods = HAMMER2_ENC_CHECK(HAMMER2_CHECK_XXHASH64) |
                                 HAMMER2_ENC_COMP(HAMMER2_COMP_AUTOZERO);
        sroot_blockref.mirror_tid = 16;
        rawip = NULL;

        /*
         * Write out the 64K HAMMER2 block containing the root and sroot.
         */
        assert((sroot_blockref.data_off & ~HAMMER2_PBUFMASK64) ==
                ((alloc_base - 1) & ~HAMMER2_PBUFMASK64));
        n = pwrite(vol->fd, buf, HAMMER2_PBUFSIZE,
                   sroot_blockref.data_off & ~HAMMER2_PBUFMASK64);
        if (n != HAMMER2_PBUFSIZE) {
                perror("write");
                exit(1);
        }
        *sroot_blockrefp = sroot_blockref;

        free(buf);
        return(alloc_base);
}

/*
 * Create the volume header, the super-root directory inode, and
 * the writable snapshot subdirectory (named via the label) which
 * is to be the initial mount point, or at least the first mount point.
 * newfs_hammer2 doesn't format the freemap bitmaps for these.
 *
 * 0                      4MB
 * [----reserved_area----][boot_area][aux_area]
 * [[vol_hdr][freemap]...]                     [sroot][root][root]...
 *     \                                        ^\     ^     ^
 *      \--------------------------------------/  \---/-----/---...
 *
 * NOTE: The total size is 8MB-aligned to avoid edge cases.
 */
static void
format_hammer2(hammer2_ondisk_t *fso, hammer2_mkfs_options_t *opt, int index)
{
        char *buf = malloc(HAMMER2_PBUFSIZE);
        hammer2_volume_t *vol = &fso->volumes[index];
        hammer2_volume_data_t *voldata;
        hammer2_blockset_t sroot_blockset;
        hammer2_off_t boot_base = HAMMER2_ZONE_SEG;
        hammer2_off_t aux_base = boot_base + opt->BootAreaSize;
        hammer2_off_t alloc_base;
        size_t n;
        int i;

        /*
         * Make sure we can write to the last usable block.
         */
        bzero(buf, HAMMER2_PBUFSIZE);
        n = pwrite(vol->fd, buf, HAMMER2_PBUFSIZE,
                   vol->size - HAMMER2_PBUFSIZE);
        if (n != HAMMER2_PBUFSIZE) {
                perror("write (at-end-of-volume)");
                exit(1);
        }

        /*
         * Format misc area and sroot/root inodes for the root volume.
         */
        bzero(&sroot_blockset, sizeof(sroot_blockset));
        if (vol->id == HAMMER2_ROOT_VOLUME) {
                alloc_base = format_hammer2_misc(vol, opt, boot_base, aux_base);
                alloc_base = format_hammer2_inode(vol, opt,
                                                  &sroot_blockset.blockref[0],
                                                  alloc_base);
        } else {
                alloc_base = 0;
                for (i = 0; i < HAMMER2_SET_COUNT; ++i)
                        sroot_blockset.blockref[i].type = HAMMER2_BREF_TYPE_INVALID;
        }

        /*
         * Format the volume header.
         *
         * The volume header points to sroot_blockset.  Also be absolutely
         * sure that allocator_beg is set for the root volume.
         */
        assert(HAMMER2_VOLUME_BYTES <= HAMMER2_PBUFSIZE);
        bzero(buf, HAMMER2_PBUFSIZE);
        voldata = (void *)buf;

        voldata->magic = HAMMER2_VOLUME_ID_HBO;
        if (vol->id == HAMMER2_ROOT_VOLUME) {
                voldata->boot_beg = boot_base;
                voldata->boot_end = boot_base + opt->BootAreaSize;
                voldata->aux_beg = aux_base;
                voldata->aux_end = aux_base + opt->AuxAreaSize;
        }
        voldata->volu_size = vol->size;
        voldata->version = opt->Hammer2Version;
        voldata->flags = 0;

        if (voldata->version >= HAMMER2_VOL_VERSION_MULTI_VOLUMES) {
                voldata->volu_id = vol->id;
                voldata->nvolumes = fso->nvolumes;
                voldata->total_size = fso->total_size;
                for (i = 0; i < HAMMER2_MAX_VOLUMES; ++i) {
                        if (i < fso->nvolumes)
                                voldata->volu_loff[i] = fso->volumes[i].offset;
                        else
                                voldata->volu_loff[i] = (hammer2_off_t)-1;
                }
        }

        voldata->fsid = opt->Hammer2_VolFSID;
        voldata->fstype = opt->Hammer2_FSType;

        voldata->peer_type = DMSG_PEER_HAMMER2; /* LNK_CONN identification */

        assert(vol->id == HAMMER2_ROOT_VOLUME || alloc_base == 0);
        voldata->allocator_size = fso->free_size;
        if (vol->id == HAMMER2_ROOT_VOLUME) {
                voldata->allocator_free = fso->free_size;
                voldata->allocator_beg = alloc_base;
        }

        voldata->sroot_blockset = sroot_blockset;
        voldata->mirror_tid = 16;       /* all blockref mirror TIDs set to 16 */
        voldata->freemap_tid = 16;      /* all blockref mirror TIDs set to 16 */
        voldata->icrc_sects[HAMMER2_VOL_ICRC_SECT1] =
                        hammer2_icrc32((char *)voldata + HAMMER2_VOLUME_ICRC1_OFF,
                                       HAMMER2_VOLUME_ICRC1_SIZE);

        /*
         * Set ICRC_SECT0 after all remaining elements of sect0 have been
         * populated in the volume header.  Note hat ICRC_SECT* (except for
         * SECT0) are part of sect0.
         */
        voldata->icrc_sects[HAMMER2_VOL_ICRC_SECT0] =
                        hammer2_icrc32((char *)voldata + HAMMER2_VOLUME_ICRC0_OFF,
                                       HAMMER2_VOLUME_ICRC0_SIZE);
        voldata->icrc_volheader =
                        hammer2_icrc32((char *)voldata + HAMMER2_VOLUME_ICRCVH_OFF,
                                       HAMMER2_VOLUME_ICRCVH_SIZE);

        /*
         * Write the volume header and all alternates.
         */
        for (i = 0; i < HAMMER2_NUM_VOLHDRS; ++i) {
                if (i * HAMMER2_ZONE_BYTES64 >= vol->size)
                        break;
                n = pwrite(vol->fd, buf, HAMMER2_PBUFSIZE,
                           i * HAMMER2_ZONE_BYTES64);
                if (n != HAMMER2_PBUFSIZE) {
                        perror("write");
                        exit(1);
                }
        }
        fsync(vol->fd);

        /*
         * Cleanup
         */
        free(buf);
}

static void
alloc_direct(hammer2_off_t *basep, hammer2_blockref_t *bref, size_t bytes)
{
        int radix;

        radix = 0;
        assert(bytes);
        while ((bytes & 1) == 0) {
                bytes >>= 1;
                ++radix;
        }
        assert(bytes == 1);
        if (radix < HAMMER2_RADIX_MIN)
                radix = HAMMER2_RADIX_MIN;

        bzero(bref, sizeof(*bref));
        bref->data_off = *basep | radix;
        bref->vradix = radix;

        *basep += 1U << radix;
}

static int
blkrefary_cmp(const void *b1, const void *b2)
{
        const hammer2_blockref_t *bref1 = b1;
        const hammer2_blockref_t *bref2 = b2;

        if (bref1->key < bref2->key)
                return(-1);
        if (bref1->key > bref2->key)
                return(1);
        return 0;
}

void
hammer2_mkfs(int ac, char **av, hammer2_mkfs_options_t *opt)
{
        hammer2_off_t resid = 0, reserved_size;
        hammer2_ondisk_t fso;
        int i;
        char *vol_fsid = NULL;
        char *sup_clid_name = NULL;
        char *sup_fsid_name = NULL;
        char *pfs_clid_name = NULL;
        char *pfs_fsid_name = NULL;

        /*
         * Sanity check basic filesystem structures.  No cookies for us
         * if it gets broken!
         */
        assert(sizeof(hammer2_volume_data_t) == HAMMER2_VOLUME_BYTES);
        assert(sizeof(hammer2_inode_data_t) == HAMMER2_INODE_BYTES);
        assert(sizeof(hammer2_blockref_t) == HAMMER2_BLOCKREF_BYTES);

        /*
         * Construct volumes information.
         * 1GB alignment (level1 freemap size) for volumes except for the last.
         * For the last volume, typically 8MB alignment to avoid edge cases for
         * reserved blocks and so raid stripes (if any) operate efficiently.
         */
        hammer2_init_ondisk(&fso);
        fso.version = opt->Hammer2Version;
        fso.nvolumes = ac;

        assert(ac >= 1);
        if (opt->NFileSystemSizes == 1) {
                resid = opt->FileSystemSize[0];
                assert(resid >= HAMMER2_FREEMAP_LEVEL1_SIZE);
        } else if (opt->NFileSystemSizes > 1) {
                if (ac != opt->NFileSystemSizes)
                        errx(1, "Invalid filesystem size count %d vs %d",
                            opt->NFileSystemSizes, ac);
        }

        for (i = 0; i < fso.nvolumes; ++i) {
                hammer2_volume_t *vol = &fso.volumes[i];
                hammer2_off_t size;
                int fd = open(av[i], O_RDWR);
                if (fd < 0)
                        err(1, "Unable to open %s R+W", av[i]);
                size = check_volume(fd);

                /*
                 * Limit size if a smaller filesystem size is specified.
                 */
                if (opt->NFileSystemSizes == 1) {
                        if (resid == 0)
                                errx(1, "No remaining filesystem size for %s",
                                    av[i]);
                        if (size > resid)
                                size = resid;
                        resid -= size;
                } else if (opt->NFileSystemSizes > 1) {
                        resid = opt->FileSystemSize[i];
                        assert(resid >= HAMMER2_FREEMAP_LEVEL1_SIZE);
                        if (size > resid)
                                size = resid;
                }

                if (i == fso.nvolumes - 1)
                        size &= ~HAMMER2_VOLUME_ALIGNMASK64;
                else
                        size &= ~HAMMER2_FREEMAP_LEVEL1_MASK;
                if (size == 0)
                        errx(1, "%s has aligned size of 0", av[i]);
                hammer2_install_volume(vol, fd, i, av[i], fso.total_size, size);
                fso.total_size += size;
        }

        /*
         * Verify volumes constructed above.
         */
        for (i = 0; i < fso.nvolumes; ++i) {
                hammer2_volume_t *vol = &fso.volumes[i];
                printf("Volume %-15s size %s\n", vol->path,
                       sizetostr(vol->size));
        }
        hammer2_verify_volumes(&fso, NULL);

        /*
         * Adjust options.
         */
        adjust_options(&fso, opt);

        /*
         * We'll need to stuff this in the volume header soon.
         */
        hammer2_uuid_to_str(&opt->Hammer2_VolFSID, &vol_fsid);
        hammer2_uuid_to_str(&opt->Hammer2_SupCLID, &sup_clid_name);
        hammer2_uuid_to_str(&opt->Hammer2_SupFSID, &sup_fsid_name);

        /*
         * Calculate the amount of reserved space.  HAMMER2_ZONE_SEG (4MB)
         * is reserved at the beginning of every 1GB of storage, rounded up.
         * Thus a 200MB filesystem will still have a 4MB reserve area.
         *
         * We also include the boot and aux areas in the reserve.  The
         * reserve is used to help 'df' calculate the amount of available
         * space.
         *
         * XXX I kinda screwed up and made the reserved area on the LEVEL1
         *     boundary rather than the ZONE boundary.  LEVEL1 is on 1GB
         *     boundaries rather than 2GB boundaries.  Stick with the LEVEL1
         *     boundary.
         */
        reserved_size = ((fso.total_size + HAMMER2_FREEMAP_LEVEL1_MASK) /
                          HAMMER2_FREEMAP_LEVEL1_SIZE) * HAMMER2_ZONE_SEG64;

        fso.free_size = fso.total_size - reserved_size - opt->BootAreaSize - opt->AuxAreaSize;
        if ((int64_t)fso.free_size < 0) {
                fprintf(stderr, "Not enough free space\n");
                exit(1);
        }

        /*
         * Format HAMMER2 volumes.
         */
        for (i = 0; i < fso.nvolumes; ++i)
                format_hammer2(&fso, opt, i);

        printf("---------------------------------------------\n");
        printf("version:          %d\n", opt->Hammer2Version);
        printf("total-size:       %s (%jd bytes)\n",
               sizetostr(fso.total_size),
               (intmax_t)fso.total_size);
        printf("boot-area-size:   %s (%jd bytes)\n",
               sizetostr(opt->BootAreaSize),
               (intmax_t)opt->BootAreaSize);
        printf("aux-area-size:    %s (%jd bytes)\n",
               sizetostr(opt->AuxAreaSize),
               (intmax_t)opt->AuxAreaSize);
        printf("topo-reserved:    %s (%jd bytes)\n",
               sizetostr(reserved_size),
               (intmax_t)reserved_size);
        printf("free-size:        %s (%jd bytes)\n",
               sizetostr(fso.free_size),
               (intmax_t)fso.free_size);
        printf("vol-fsid:         %s\n", vol_fsid);
        printf("sup-clid:         %s\n", sup_clid_name);
        printf("sup-fsid:         %s\n", sup_fsid_name);
        for (i = 0; i < opt->NLabels; ++i) {
                printf("PFS \"%s\"\n", opt->Label[i]);
                hammer2_uuid_to_str(&opt->Hammer2_PfsCLID[i], &pfs_clid_name);
                hammer2_uuid_to_str(&opt->Hammer2_PfsFSID[i], &pfs_fsid_name);
                printf("    clid %s\n", pfs_clid_name);
                printf("    fsid %s\n", pfs_fsid_name);
        }
        if (opt->DebugOpt) {
                printf("---------------------------------------------\n");
                hammer2_print_volumes(&fso);
        }

        free(vol_fsid);
        free(sup_clid_name);
        free(sup_fsid_name);
        free(pfs_clid_name);
        free(pfs_fsid_name);

        for (i = 0; i < fso.nvolumes; ++i)
                hammer2_uninstall_volume(&fso.volumes[i]);
}