kernel: Fix stop_cpus()/restart_cpus() usages when panicing.

[dragonfly.git] / sbin / newfs_hammer / newfs_hammer.c

/*
 * Copyright (c) 2007 The DragonFly Project.  All rights reserved.
 *
 * This code is derived from software contributed to The DragonFly Project
 * by Matthew Dillon <dillon@backplane.com>
 *
 * 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/sysctl.h>
#include <sys/ioctl_compat.h>

#include "hammer_util.h"

static int64_t getsize(const char *str, int pw);
static int trim_volume(struct volume_info *vol);
static void format_volume(struct volume_info *vol, int nvols,const char *label);
static hammer_off_t format_root_directory(const char *label);
static uint64_t nowtime(void);
static void print_volume(const struct volume_info *vol);
static void usage(int exit_code);
static void test_header_junk_size(int64_t size);
static void test_boot_area_size(int64_t size);
static void test_memory_log_size(int64_t size);
static void test_undo_buffer_size(int64_t size);

static int ForceOpt;
static int64_t HeaderJunkSize = -1;
static int64_t BootAreaSize = -1;
static int64_t MemoryLogSize = -1;
static int64_t UndoBufferSize;
static int HammerVersion = -1;

#define GIG     (1024LL*1024*1024)

int
main(int ac, char **av)
{
        uint32_t status;
        off_t total;
        off_t avg_vol_size;
        int ch;
        int i;
        int nvols;
        int eflag = 0;
        const char *label = NULL;
        struct volume_info *vol;

        /*
         * Sanity check basic filesystem structures.  No cookies for us
         * if it gets broken!
         */
        assert(sizeof(struct hammer_volume_ondisk) <= HAMMER_BUFSIZE);
        assert(sizeof(struct hammer_volume_ondisk) <= HAMMER_MIN_VOL_JUNK);
        assert(sizeof(struct hammer_blockmap_layer1) == 32);
        assert(sizeof(struct hammer_blockmap_layer2) == 16);

        /*
         * Parse arguments
         */
        while ((ch = getopt(ac, av, "dfEL:j:b:m:u:hC:V:")) != -1) {
                switch(ch) {
                case 'd':
                        ++DebugOpt;
                        break;
                case 'f':
                        ForceOpt = 1;
                        break;
                case 'E':
                        eflag = 1;
                        break;
                case 'L':
                        label = optarg;
                        break;
                case 'j': /* Not mentioned in newfs_hammer(8) */
                        HeaderJunkSize = getsize(optarg, 2);
                        test_header_junk_size(HeaderJunkSize);
                        break;
                case 'b':
                        BootAreaSize = getsize(optarg, 2);
                        test_boot_area_size(BootAreaSize);
                        break;
                case 'm':
                        MemoryLogSize = getsize(optarg, 2);
                        test_memory_log_size(MemoryLogSize);
                        break;
                case 'u':
                        UndoBufferSize = getsize(optarg, 2);
                        test_undo_buffer_size(UndoBufferSize);
                        break;
                case 'h':
                        usage(0);
                        break;
                case 'C':
                        if (hammer_parse_cache_size(optarg) == -1)
                                usage(1);
                        break;
                case 'V':
                        HammerVersion = strtol(optarg, NULL, 0);
                        if (HammerVersion < HAMMER_VOL_VERSION_MIN ||
                            HammerVersion >= HAMMER_VOL_VERSION_WIP) {
                                errx(1,
                                     "I don't understand how to format "
                                     "HAMMER version %d",
                                     HammerVersion);
                        }
                        break;
                default:
                        usage(1);
                        break;
                }
        }
        ac -= optind;
        av += optind;
        nvols = ac;

        if (label == NULL) {
                fprintf(stderr,
                        "newfs_hammer: A filesystem label must be specified\n");
                usage(1);
        }

        if (HammerVersion < 0) {
                size_t olen = sizeof(HammerVersion);
                HammerVersion = HAMMER_VOL_VERSION_DEFAULT;
                if (sysctlbyname("vfs.hammer.supported_version",
                                 &HammerVersion, &olen, NULL, 0) == 0) {
                        if (HammerVersion >= HAMMER_VOL_VERSION_WIP) {
                                HammerVersion = HAMMER_VOL_VERSION_WIP - 1;
                                fprintf(stderr,
                                        "newfs_hammer: WARNING: HAMMER VFS "
                                        "supports higher version than I "
                                        "understand,\n"
                                        "using version %d\n",
                                        HammerVersion);
                        }
                } else {
                        fprintf(stderr,
                                "newfs_hammer: WARNING: HAMMER VFS not "
                                "loaded, cannot get version info.\n"
                                "Using version %d\n",
                                HAMMER_VOL_VERSION_DEFAULT);
                }
        }

        if (nvols == 0) {
                fprintf(stderr,
                        "newfs_hammer: You must specify at least one "
                        "special file (volume)\n");
                exit(1);
        }

        if (nvols > HAMMER_MAX_VOLUMES) {
                fprintf(stderr,
                        "newfs_hammer: The maximum number of volumes is %d\n",
                        HAMMER_MAX_VOLUMES);
                exit(1);
        }

        /*
         * Generate a filesystem id and lookup the filesystem type
         */
        uuidgen(&Hammer_FSId, 1);
        uuid_name_lookup(&Hammer_FSType, HAMMER_FSTYPE_STRING, &status);
        if (status != uuid_s_ok) {
                errx(1, "uuids file does not have the DragonFly "
                        "HAMMER filesystem type");
        }

        total = 0;
        for (i = 0; i < nvols; ++i) {
                vol = init_volume(av[i], O_RDWR, i);
                printf("Volume %d %s %-15s size %s\n",
                        vol->vol_no, vol->type, vol->name,
                        sizetostr(vol->size));

                if (eflag) {
                        int res = trim_volume(vol);
                        if (res == -1 || (res == 1 && ForceOpt == 0))
                                exit(1);
                }
                total += vol->size;
        }

        /*
         * Reserve space for (future) header junk, setup our poor-man's
         * big-block allocator.  Note that the header junk space includes
         * volume header which is 1928 bytes.
         */
        if (HeaderJunkSize == -1)
                HeaderJunkSize = HAMMER_VOL_JUNK_SIZE;
        else if (HeaderJunkSize < (int64_t)sizeof(struct hammer_volume_ondisk))
                HeaderJunkSize = sizeof(struct hammer_volume_ondisk);
        HeaderJunkSize = HAMMER_BUFSIZE_DOALIGN(HeaderJunkSize);

        /*
         * Calculate defaults for the boot area and memory log sizes,
         * only if not specified by -b or -m option.
         */
        avg_vol_size = total / nvols;
        if (BootAreaSize == -1)
                BootAreaSize = init_boot_area_size(BootAreaSize, avg_vol_size);
        if (MemoryLogSize == -1)
                MemoryLogSize = init_memory_log_size(MemoryLogSize, avg_vol_size);

        /*
         * Format the volumes.  Format the root volume first so we can
         * bootstrap the freemap.
         */
        format_volume(get_root_volume(), nvols, label);
        for (i = 0; i < nvols; ++i) {
                if (i != HAMMER_ROOT_VOLNO)
                        format_volume(get_volume(i), nvols, label);
        }

        print_volume(get_root_volume());

        flush_all_volumes();
        return(0);
}

static
void
print_volume(const struct volume_info *vol)
{
        hammer_volume_ondisk_t ondisk;
        hammer_blockmap_t blockmap;
        hammer_off_t total = 0;
        int i, nvols;
        uint32_t status;
        const char *name = NULL;
        char *fsidstr;

        ondisk = vol->ondisk;
        blockmap = &ondisk->vol0_blockmap[HAMMER_ZONE_UNDO_INDEX];

        nvols = ondisk->vol_count;
        for (i = 0; i < nvols; ++i) {
                struct volume_info *p = get_volume(i);
                total += p->size;
                if (p->vol_no == HAMMER_ROOT_VOLNO) {
                        assert(name == NULL);
                        name = p->name;
                }
        }

        uuid_to_string(&Hammer_FSId, &fsidstr, &status);

        printf("---------------------------------------------\n");
        printf("HAMMER version %d\n", HammerVersion);
        printf("%d volume%s total size %s\n",
                nvols, (nvols == 1 ? "" : "s"), sizetostr(total));
        printf("root-volume:         %s\n", name);
        if (DebugOpt)
                printf("header-junk-size:    %s\n",
                        sizetostr(ondisk->vol_bot_beg));
        printf("boot-area-size:      %s\n",
                sizetostr(ondisk->vol_mem_beg - ondisk->vol_bot_beg));
        printf("memory-log-size:     %s\n",
                sizetostr(ondisk->vol_buf_beg - ondisk->vol_mem_beg));
        printf("undo-buffer-size:    %s\n",
                sizetostr(HAMMER_OFF_LONG_ENCODE(blockmap->alloc_offset)));
        printf("total-pre-allocated: %s\n",
                sizetostr(HAMMER_OFF_SHORT_ENCODE(vol->vol_free_off)));
        printf("fsid:                %s\n", fsidstr);
        printf("\n");
        printf("NOTE: Please remember that you may have to manually set up a\n"
                "cron(8) job to prune and reblock the filesystem regularly.\n"
                "By default, the system automatically runs 'hammer cleanup'\n"
                "on a nightly basis.  The periodic.conf(5) variable\n"
                "'daily_clean_hammer_enable' can be unset to disable this.\n"
                "Also see 'man hammer' and 'man HAMMER' for more information.\n");
        if (total < 10*GIG) {
                printf("\nWARNING: The minimum UNDO/REDO FIFO is %s, "
                        "you really should not\n"
                        "try to format a HAMMER filesystem this small.\n",
                        sizetostr(HAMMER_BIGBLOCK_SIZE *
                               HAMMER_MIN_UNDO_BIGBLOCKS));
        }
        if (total < 50*GIG) {
                printf("\nWARNING: HAMMER filesystems less than 50GB are "
                        "not recommended!\n"
                        "You may have to run 'hammer prune-everything' and "
                        "'hammer reblock'\n"
                        "quite often, even if using a nohistory mount.\n");
        }
}

static
void
usage(int exit_code)
{
        fprintf(stderr,
                "usage: newfs_hammer -L label [-Efh] [-b bootsize] [-m savesize] [-u undosize]\n"
                "                    [-C cachesize[:readahead]] [-V version] special ...\n"
        );
        exit(exit_code);
}

static void
test_header_junk_size(int64_t size)
{
        if (size < HAMMER_MIN_VOL_JUNK) {
                if (ForceOpt == 0) {
                        errx(1, "The minimum header junk size is %s",
                                sizetostr(HAMMER_MIN_VOL_JUNK));
                } else {
                        fprintf(stderr,
                                "WARNING: you have specified "
                                "header junk size less than %s.\n",
                                sizetostr(HAMMER_MIN_VOL_JUNK));
                }
        } else if (size > HAMMER_MAX_VOL_JUNK) {
                errx(1, "The maximum header junk size is %s",
                        sizetostr(HAMMER_MAX_VOL_JUNK));
        }
}

static void
test_boot_area_size(int64_t size)
{
        if (size < HAMMER_BOOT_MINBYTES) {
                if (ForceOpt == 0) {
                        errx(1, "The minimum boot area size is %s",
                                sizetostr(HAMMER_BOOT_MINBYTES));
                } else {
                        fprintf(stderr,
                                "WARNING: you have specified "
                                "boot area size less than %s.\n",
                                sizetostr(HAMMER_BOOT_MINBYTES));
                }
        } else if (size > HAMMER_BOOT_MAXBYTES) {
                errx(1, "The maximum boot area size is %s",
                        sizetostr(HAMMER_BOOT_MAXBYTES));
        }
}

static void
test_memory_log_size(int64_t size)
{
        if (size < HAMMER_MEM_MINBYTES) {
                if (ForceOpt == 0) {
                        errx(1, "The minimum memory log size is %s",
                                sizetostr(HAMMER_MEM_MINBYTES));
                } else {
                        fprintf(stderr,
                                "WARNING: you have specified "
                                "memory log size less than %s.\n",
                                sizetostr(HAMMER_MEM_MINBYTES));
                }
        } else if (size > HAMMER_MEM_MAXBYTES) {
                errx(1, "The maximum memory log size is %s",
                        sizetostr(HAMMER_MEM_MAXBYTES));
        }
}

static void
test_undo_buffer_size(int64_t size)
{
        int64_t minbuf, maxbuf;

        minbuf = HAMMER_BIGBLOCK_SIZE * HAMMER_MIN_UNDO_BIGBLOCKS;
        maxbuf = HAMMER_BIGBLOCK_SIZE * HAMMER_MAX_UNDO_BIGBLOCKS;

        if (size < minbuf) {
                if (ForceOpt == 0) {
                        errx(1, "The minimum UNDO/REDO FIFO size is %s",
                                sizetostr(minbuf));
                } else {
                        fprintf(stderr,
                                "WARNING: you have specified an "
                                "UNDO/REDO FIFO size less than %s,\n"
                                "which may lead to VFS panics.\n",
                                sizetostr(minbuf));
                }
        } else if (size > maxbuf) {
                errx(1, "The maximum UNDO/REDO FIFO size is %s",
                        sizetostr(maxbuf));
        }
}

/*
 * Convert a string to a 64 bit signed integer with various requirements.
 */
static int64_t
getsize(const char *str, 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 ((powerof2 & 1) && (val ^ (val - 1)) != ((val << 1) - 1)) {
                errx(1, "Value not power of 2: %s", str);
                /* not reached */
        }
        if ((powerof2 & 2) && (val & HAMMER_BUFMASK)) {
                errx(1, "Value not an integral multiple of %dK: %s",
                     HAMMER_BUFSIZE / 1024, str);
                /* not reached */
        }
        return(val);
}

/*
 * Generate a transaction id.  Transaction ids are no longer time-based.
 * Put the nail in the coffin by not making the first one time-based.
 *
 * We could start at 1 here but start at 2^32 to reserve a small domain for
 * possible future use.
 */
static hammer_tid_t
createtid(void)
{
        static hammer_tid_t lasttid;

        if (lasttid == 0)
                lasttid = 0x0000000100000000ULL;
        return(lasttid++);
}

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

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

/*
 * TRIM the volume, but only if the backing store is a DEVICE
 */
static
int
trim_volume(struct volume_info *vol)
{
        size_t olen;
        char *dev_name, *p;
        char sysctl_name[64];
        int trim_enabled;
        off_t ioarg[2];

        if (strcmp(vol->type, "DEVICE")) {
                fprintf(stderr, "Cannot TRIM regular file %s\n", vol->name);
                return(1);
        }
        if (strncmp(vol->name, "/dev/da", 7)) {
                fprintf(stderr, "%s does not support the TRIM command\n",
                        vol->name);
                return(1);
        }

        /* Extract a number from /dev/da?s? */
        dev_name = strdup(vol->name);
        p = strtok(dev_name + strlen("/dev/da"), "s");
        sprintf(sysctl_name, "kern.cam.da.%s.trim_enabled", p);
        free(dev_name);

        trim_enabled = 0;
        olen = sizeof(trim_enabled);

        if (sysctlbyname(sysctl_name, &trim_enabled, &olen, NULL, 0) == -1) {
                fprintf(stderr, "%s (%s) does not support the TRIM command\n",
                        vol->name, sysctl_name);
                return(1);
        }
        if (!trim_enabled) {
                fprintf(stderr, "Erase device option selected, but sysctl (%s) "
                        "is not enabled\n", sysctl_name);
                return(1);
        }

        ioarg[0] = vol->device_offset;
        ioarg[1] = vol->size;

        printf("Trimming %s %s, sectors %llu-%llu\n",
                vol->type, vol->name,
                (unsigned long long)ioarg[0] / 512,
                (unsigned long long)ioarg[1] / 512);

        if (ioctl(vol->fd, IOCTLTRIM, ioarg) == -1) {
                fprintf(stderr, "Device trim failed\n");
                return(-1);
        }

        return(0);
}

/*
 * Format a HAMMER volume.
 */
static
void
format_volume(struct volume_info *vol, int nvols, const char *label)
{
        struct volume_info *root_vol;
        hammer_volume_ondisk_t ondisk;
        int64_t freeblks;
        int64_t freebytes;
        int64_t vol_buf_size;
        hammer_off_t vol_alloc;
        int i;

        /*
         * Initialize basic information in the on-disk volume structure.
         */
        ondisk = vol->ondisk;

        ondisk->vol_fsid = Hammer_FSId;
        ondisk->vol_fstype = Hammer_FSType;
        snprintf(ondisk->vol_label, sizeof(ondisk->vol_label), "%s", label);
        ondisk->vol_no = vol->vol_no;
        ondisk->vol_count = nvols;
        ondisk->vol_version = HammerVersion;

        vol_alloc = HeaderJunkSize;
        ondisk->vol_bot_beg = vol_alloc;
        vol_alloc += BootAreaSize;
        ondisk->vol_mem_beg = vol_alloc;
        vol_alloc += MemoryLogSize;

        /*
         * The remaining area is the zone 2 buffer allocation area.
         */
        ondisk->vol_buf_beg = vol_alloc;
        ondisk->vol_buf_end = vol->size & ~(int64_t)HAMMER_BUFMASK;
        vol_buf_size = HAMMER_VOL_BUF_SIZE(ondisk);

        if (vol_buf_size < 0) {
                errx(1, "volume %d %s is too small to hold the volume header",
                     vol->vol_no, vol->name);
        }

        if ((vol_buf_size & ~HAMMER_OFF_SHORT_MASK) != 0) {
                errx(1, "volume %d %s is too large", vol->vol_no, vol->name);
        }

        ondisk->vol_rootvol = HAMMER_ROOT_VOLNO;
        ondisk->vol_signature = HAMMER_FSBUF_VOLUME;

        vol->vol_free_off = HAMMER_ENCODE_RAW_BUFFER(vol->vol_no, 0);
        vol->vol_free_end = HAMMER_ENCODE_RAW_BUFFER(vol->vol_no,
                                vol_buf_size & ~HAMMER_BIGBLOCK_MASK64);

        /*
         * Format the root volume.
         */
        if (vol->vol_no == HAMMER_ROOT_VOLNO) {
                /*
                 * Check freemap counts before formatting
                 */
                freeblks = count_freemap(vol);
                freebytes = freeblks * HAMMER_BIGBLOCK_SIZE64;
                if (freebytes < 10*GIG && ForceOpt == 0) {
                        errx(1, "Cannot create a HAMMER filesystem less than 10GB "
                                "unless you use -f\n(for the size of Volume %d).  "
                                "HAMMER filesystems less than 50GB are not "
                                "recommended.", HAMMER_ROOT_VOLNO);
                }

                /*
                 * Starting TID
                 */
                ondisk->vol0_next_tid = createtid();

                /*
                 * Format freemap.  vol0_stat_freebigblocks is
                 * the number of big-blocks available for anything
                 * other than freemap zone at this point.
                 */
                format_freemap(vol);
                assert(ondisk->vol0_stat_freebigblocks == 0);
                ondisk->vol0_stat_freebigblocks = initialize_freemap(vol);

                /*
                 * Format zones that are mapped to zone-2.
                 */
                for (i = 0; i < HAMMER_MAX_ZONES; ++i) {
                        if (hammer_is_zone2_mapped_index(i))
                                format_blockmap(vol, i, 0);
                }

                /*
                 * Format undo zone.  Formatting decrements
                 * vol0_stat_freebigblocks whenever a new big-block
                 * is allocated for undo zone.
                 */
                format_undomap(vol, &UndoBufferSize);
                assert(ondisk->vol0_stat_bigblocks == 0);
                ondisk->vol0_stat_bigblocks = ondisk->vol0_stat_freebigblocks;

                /*
                 * Format the root directory.  Formatting decrements
                 * vol0_stat_freebigblocks whenever a new big-block
                 * is allocated for required zones.
                 */
                ondisk->vol0_btree_root = format_root_directory(label);
                ++ondisk->vol0_stat_inodes;     /* root inode */
        } else {
                freeblks = initialize_freemap(vol);
                root_vol = get_root_volume();
                root_vol->ondisk->vol0_stat_freebigblocks += freeblks;
                root_vol->ondisk->vol0_stat_bigblocks += freeblks;
        }
}

/*
 * Format the root directory.
 */
static
hammer_off_t
format_root_directory(const char *label)
{
        hammer_off_t btree_off;
        hammer_off_t idata_off;
        hammer_off_t pfsd_off;
        hammer_tid_t create_tid;
        hammer_node_ondisk_t bnode;
        hammer_inode_data_t idata;
        hammer_pseudofs_data_t pfsd;
        struct buffer_info *data_buffer0 = NULL;
        struct buffer_info *data_buffer1 = NULL;
        struct buffer_info *data_buffer2 = NULL;
        hammer_btree_elm_t elm;
        uint64_t xtime;

        /*
         * Allocate zero-filled root btree node, inode and pfs
         */
        bnode = alloc_btree_node(&btree_off, &data_buffer0);
        idata = alloc_meta_element(&idata_off, sizeof(*idata), &data_buffer1);
        pfsd = alloc_meta_element(&pfsd_off, sizeof(*pfsd), &data_buffer2);
        create_tid = createtid();
        xtime = nowtime();

        /*
         * Populate the inode data and inode record for the root directory.
         */
        idata->version = HAMMER_INODE_DATA_VERSION;
        idata->mode = 0755;
        idata->ctime = xtime;
        idata->mtime = xtime;
        idata->atime = xtime;
        idata->obj_type = HAMMER_OBJTYPE_DIRECTORY;
        idata->size = 0;
        idata->nlinks = 1;
        if (HammerVersion >= HAMMER_VOL_VERSION_TWO)
                idata->cap_flags |= HAMMER_INODE_CAP_DIR_LOCAL_INO;
        if (HammerVersion >= HAMMER_VOL_VERSION_SIX)
                idata->cap_flags |= HAMMER_INODE_CAP_DIRHASH_ALG1;

        /*
         * Populate the PFS data for the root PFS.
         */
        pfsd->sync_low_tid = 1;
        pfsd->sync_beg_tid = 0;
        pfsd->sync_end_tid = 0; /* overriden by vol0_next_tid on pfs0 */
        pfsd->shared_uuid = Hammer_FSId;
        pfsd->unique_uuid = Hammer_FSId;
        pfsd->mirror_flags = 0;
        snprintf(pfsd->label, sizeof(pfsd->label), "%s", label);

        /*
         * Create the root of the B-Tree.  The root is a leaf node so we
         * do not have to worry about boundary elements.
         */
        bnode->parent = 0;  /* no parent */
        bnode->count = 2;
        bnode->type = HAMMER_BTREE_TYPE_LEAF;
        bnode->mirror_tid = 0;

        /*
         * Create the first node element for the inode.
         */
        elm = &bnode->elms[0];
        elm->leaf.base.btype = HAMMER_BTREE_TYPE_RECORD;
        elm->leaf.base.localization = HAMMER_DEF_LOCALIZATION |
                                      HAMMER_LOCALIZE_INODE;
        elm->leaf.base.obj_id = HAMMER_OBJID_ROOT;
        elm->leaf.base.key = 0;
        elm->leaf.base.create_tid = create_tid;
        elm->leaf.base.delete_tid = 0;
        elm->leaf.base.rec_type = HAMMER_RECTYPE_INODE;
        elm->leaf.base.obj_type = HAMMER_OBJTYPE_DIRECTORY;
        elm->leaf.create_ts = (uint32_t)time(NULL);

        elm->leaf.data_offset = idata_off;
        elm->leaf.data_len = sizeof(*idata);
        hammer_crc_set_leaf(idata, &elm->leaf);

        /*
         * Create the second node element for the PFS data.
         * This is supposed to be a record part of the root ip (inode),
         * so it should have the same obj_type value as above.
         */
        elm = &bnode->elms[1];
        elm->leaf.base.btype = HAMMER_BTREE_TYPE_RECORD;
        elm->leaf.base.localization = HAMMER_DEF_LOCALIZATION |
                                      HAMMER_LOCALIZE_MISC;
        elm->leaf.base.obj_id = HAMMER_OBJID_ROOT;
        elm->leaf.base.key = 0;
        elm->leaf.base.create_tid = create_tid;
        elm->leaf.base.delete_tid = 0;
        elm->leaf.base.rec_type = HAMMER_RECTYPE_PFS;
        elm->leaf.base.obj_type = HAMMER_OBJTYPE_DIRECTORY;
        elm->leaf.create_ts = (uint32_t)time(NULL);

        elm->leaf.data_offset = pfsd_off;
        elm->leaf.data_len = sizeof(*pfsd);
        hammer_crc_set_leaf(pfsd, &elm->leaf);

        hammer_crc_set_btree(bnode);

        rel_buffer(data_buffer0);
        rel_buffer(data_buffer1);
        rel_buffer(data_buffer2);

        return(btree_off);
}