source: mainline/uspace/srv/bd/vbd/disk.c@ 78edb5e

/*
 * Copyright (c) 2023 Jiri Svoboda
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - 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.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
 */

/** @addtogroup vbd
 * @{
 */
/**
 * @file
 */

#include <adt/list.h>
#include <bd_srv.h>
#include <block.h>
#include <errno.h>
#include <str_error.h>
#include <io/log.h>
#include <label/empty.h>
#include <label/label.h>
#include <loc.h>
#include <stdio.h>
#include <stdlib.h>
#include <task.h>
#include <vbd.h>

#include "disk.h"
#include "types/vbd.h"

loc_srv_t *vbds_srv;

static fibril_mutex_t vbds_disks_lock;
static list_t vbds_disks; /* of vbds_disk_t */
static fibril_mutex_t vbds_parts_lock;
static list_t vbds_parts; /* of vbds_part_t */

static category_id_t part_cid;

static errno_t vbds_disk_parts_add(vbds_disk_t *, label_t *);
static errno_t vbds_disk_parts_remove(vbds_disk_t *, vbds_rem_flag_t);

static errno_t vbds_bd_open(bd_srvs_t *, bd_srv_t *);
static errno_t vbds_bd_close(bd_srv_t *);
static errno_t vbds_bd_read_blocks(bd_srv_t *, aoff64_t, size_t, void *, size_t);
static errno_t vbds_bd_sync_cache(bd_srv_t *, aoff64_t, size_t);
static errno_t vbds_bd_write_blocks(bd_srv_t *, aoff64_t, size_t, const void *,
    size_t);
static errno_t vbds_bd_get_block_size(bd_srv_t *, size_t *);
static errno_t vbds_bd_get_num_blocks(bd_srv_t *, aoff64_t *);

static errno_t vbds_bsa_translate(vbds_part_t *, aoff64_t, size_t, aoff64_t *);

static errno_t vbds_part_svc_register(vbds_part_t *);
static errno_t vbds_part_svc_unregister(vbds_part_t *);
static errno_t vbds_part_indices_update(vbds_disk_t *);

static vbd_part_id_t vbds_part_id = 1;

static errno_t vbds_label_get_bsize(void *, size_t *);
static errno_t vbds_label_get_nblocks(void *, aoff64_t *);
static errno_t vbds_label_read(void *, aoff64_t, size_t, void *);
static errno_t vbds_label_write(void *, aoff64_t, size_t, const void *);

/** Block device operations provided by VBD */
static bd_ops_t vbds_bd_ops = {
        .open = vbds_bd_open,
        .close = vbds_bd_close,
        .read_blocks = vbds_bd_read_blocks,
        .sync_cache = vbds_bd_sync_cache,
        .write_blocks = vbds_bd_write_blocks,
        .get_block_size = vbds_bd_get_block_size,
        .get_num_blocks = vbds_bd_get_num_blocks
};

/** Provide disk access to liblabel */
static label_bd_ops_t vbds_label_bd_ops = {
        .get_bsize = vbds_label_get_bsize,
        .get_nblocks = vbds_label_get_nblocks,
        .read = vbds_label_read,
        .write = vbds_label_write
};

static vbds_part_t *bd_srv_part(bd_srv_t *bd)
{
        return (vbds_part_t *)bd->srvs->sarg;
}

static vbds_disk_t *vbds_disk_first(void)
{
        link_t *link;

        link = list_first(&vbds_disks);
        if (link == NULL)
                return NULL;

        return list_get_instance(link, vbds_disk_t, ldisks);
}

static vbds_disk_t *vbds_disk_next(vbds_disk_t *disk)
{
        link_t *link;

        if (disk == NULL)
                return NULL;

        link = list_next(&disk->ldisks, &vbds_disks);
        if (link == NULL)
                return NULL;

        return list_get_instance(link, vbds_disk_t, ldisks);
}

errno_t vbds_disks_init(void)
{
        errno_t rc;

        fibril_mutex_initialize(&vbds_disks_lock);
        list_initialize(&vbds_disks);
        fibril_mutex_initialize(&vbds_parts_lock);
        list_initialize(&vbds_parts);

        rc = loc_category_get_id("partition", &part_cid, 0);
        if (rc != EOK) {
                log_msg(LOG_DEFAULT, LVL_ERROR, "Error looking up partition "
                    "category.");
                return EIO;
        }

        return EOK;
}

/** Check for new/removed disk devices */
static errno_t vbds_disks_check_new(void)
{
        bool already_known;
        category_id_t disk_cat;
        service_id_t *svcs;
        size_t count, i;
        vbds_disk_t *cur, *next;
        errno_t rc;

        log_msg(LOG_DEFAULT, LVL_DEBUG, "vbds_disks_check_new()");

        fibril_mutex_lock(&vbds_disks_lock);

        rc = loc_category_get_id("disk", &disk_cat, IPC_FLAG_BLOCKING);
        if (rc != EOK) {
                log_msg(LOG_DEFAULT, LVL_ERROR, "Failed resolving category 'disk'.");
                fibril_mutex_unlock(&vbds_disks_lock);
                return ENOENT;
        }

        rc = loc_category_get_svcs(disk_cat, &svcs, &count);
        if (rc != EOK) {
                log_msg(LOG_DEFAULT, LVL_ERROR, "Failed getting list of disk "
                    "devices.");
                fibril_mutex_unlock(&vbds_disks_lock);
                return EIO;
        }

        list_foreach(vbds_disks, ldisks, vbds_disk_t, disk)
                disk->present = false;

        for (i = 0; i < count; i++) {
                already_known = false;

                list_foreach(vbds_disks, ldisks, vbds_disk_t, disk) {
                        if (disk->svc_id == svcs[i]) {
                                already_known = true;
                                disk->present = true;
                                break;
                        }
                }

                if (!already_known) {
                        log_msg(LOG_DEFAULT, LVL_NOTE, "Found disk '%lu'",
                            (unsigned long) svcs[i]);
                        rc = vbds_disk_add(svcs[i]);
                        if (rc != EOK) {
                                log_msg(LOG_DEFAULT, LVL_ERROR, "Could not add "
                                    "disk.");
                        }
                } else {
                        log_msg(LOG_DEFAULT, LVL_DEBUG, "Disk %lu already known",
                            (unsigned long) svcs[i]);
                }
        }

        cur = vbds_disk_first();
        while (cur != NULL) {
                next = vbds_disk_next(cur);
                if (!cur->present) {
                        log_msg(LOG_DEFAULT, LVL_NOTE, "Disk '%lu' is gone",
                            (unsigned long) cur->svc_id);
                        rc = vbds_disk_remove(cur->svc_id);
                        if (rc != EOK) {
                                log_msg(LOG_DEFAULT, LVL_ERROR, "Could not "
                                    "remove disk.");
                        }
                }

                cur = next;
        }

        fibril_mutex_unlock(&vbds_disks_lock);
        return EOK;
}

static errno_t vbds_disk_by_svcid(service_id_t sid, vbds_disk_t **rdisk)
{
        list_foreach(vbds_disks, ldisks, vbds_disk_t, disk) {
                if (disk->svc_id == sid) {
                        *rdisk = disk;
                        return EOK;
                }
        }

        return ENOENT;
}

static void vbds_part_add_ref(vbds_part_t *part)
{
        log_msg(LOG_DEFAULT, LVL_DEBUG2, "vbds_part_add_ref");
        refcount_up(&part->refcnt);
}

static void vbds_part_del_ref(vbds_part_t *part)
{
        log_msg(LOG_DEFAULT, LVL_DEBUG2, "vbds_part_del_ref");
        if (refcount_down(&part->refcnt)) {
                log_msg(LOG_DEFAULT, LVL_DEBUG2, " - free part");
                free(part);
        }
}

static errno_t vbds_part_by_pid(vbds_part_id_t partid, vbds_part_t **rpart)
{
        log_msg(LOG_DEFAULT, LVL_DEBUG, "vbds_part_by_pid(%zu)", partid);

        fibril_mutex_lock(&vbds_parts_lock);

        list_foreach(vbds_parts, lparts, vbds_part_t, part) {
                log_msg(LOG_DEFAULT, LVL_DEBUG, "%zu == %zu ?", part->pid, partid);
                if (part->pid == partid) {
                        log_msg(LOG_DEFAULT, LVL_DEBUG, "Found match.");
                        vbds_part_add_ref(part);
                        fibril_mutex_unlock(&vbds_parts_lock);
                        *rpart = part;
                        return EOK;
                }
        }

        fibril_mutex_unlock(&vbds_parts_lock);
        log_msg(LOG_DEFAULT, LVL_DEBUG, "No match.");
        return ENOENT;
}

static errno_t vbds_part_by_svcid(service_id_t svcid, vbds_part_t **rpart)
{
        log_msg(LOG_DEFAULT, LVL_DEBUG, "vbds_part_by_svcid(%zu)", svcid);

        fibril_mutex_lock(&vbds_parts_lock);

        list_foreach(vbds_parts, lparts, vbds_part_t, part) {
                log_msg(LOG_DEFAULT, LVL_DEBUG, "%zu == %zu ?", part->svc_id, svcid);
                if (part->svc_id == svcid) {
                        log_msg(LOG_DEFAULT, LVL_DEBUG, "Found match.");
                        vbds_part_add_ref(part);
                        fibril_mutex_unlock(&vbds_parts_lock);
                        *rpart = part;
                        return EOK;
                }
        }

        fibril_mutex_unlock(&vbds_parts_lock);
        log_msg(LOG_DEFAULT, LVL_DEBUG, "No match.");
        return ENOENT;
}

/** Add partition to our inventory based on liblabel partition structure */
static errno_t vbds_part_add(vbds_disk_t *disk, label_part_t *lpart,
    vbds_part_t **rpart)
{
        vbds_part_t *part;
        service_id_t psid = 0;
        label_part_info_t lpinfo;
        errno_t rc;

        log_msg(LOG_DEFAULT, LVL_DEBUG, "vbds_part_add(%s, %p)",
            disk->svc_name, lpart);

        label_part_get_info(lpart, &lpinfo);

        part = calloc(1, sizeof(vbds_part_t));
        if (part == NULL) {
                log_msg(LOG_DEFAULT, LVL_ERROR, "Out of memory.");
                return ENOMEM;
        }

        fibril_rwlock_initialize(&part->lock);

        part->lpart = lpart;
        part->disk = disk;
        part->pid = ++vbds_part_id;
        part->svc_id = psid;
        part->block0 = lpinfo.block0;
        part->nblocks = lpinfo.nblocks;
        refcount_init(&part->refcnt);

        bd_srvs_init(&part->bds);
        part->bds.ops = &vbds_bd_ops;
        part->bds.sarg = part;

        if (lpinfo.pkind != lpk_extended) {
                rc = vbds_part_svc_register(part);
                if (rc != EOK) {
                        free(part);
                        return EIO;
                }
        }

        list_append(&part->ldisk, &disk->parts);
        fibril_mutex_lock(&vbds_parts_lock);
        list_append(&part->lparts, &vbds_parts);
        fibril_mutex_unlock(&vbds_parts_lock);

        log_msg(LOG_DEFAULT, LVL_DEBUG, "vbds_part_add -> %p", part);

        if (rpart != NULL)
                *rpart = part;
        return EOK;
}

/** Remove partition from our inventory leaving only the underlying liblabel
 * partition structure.
 *
 * @param part   Partition
 * @param flag   If set to @c vrf_force, force removal even if partition is in use
 * @param rlpart Place to store pointer to liblabel partition
 *
 */
static errno_t vbds_part_remove(vbds_part_t *part, vbds_rem_flag_t flag,
    label_part_t **rlpart)
{
        label_part_t *lpart;
        errno_t rc;

        log_msg(LOG_DEFAULT, LVL_DEBUG, "vbds_part_remove(%p)", part);

        fibril_rwlock_write_lock(&part->lock);
        lpart = part->lpart;

        if ((flag & vrf_force) == 0 && part->open_cnt > 0) {
                fibril_rwlock_write_unlock(&part->lock);
                log_msg(LOG_DEFAULT, LVL_DEBUG, "part->open_cnt = %d",
                    part->open_cnt);
                return EBUSY;
        }

        if (part->svc_id != 0) {
                rc = vbds_part_svc_unregister(part);
                if (rc != EOK) {
                        fibril_rwlock_write_unlock(&part->lock);
                        return EIO;
                }
        }

        list_remove(&part->ldisk);
        fibril_mutex_lock(&vbds_parts_lock);
        list_remove(&part->lparts);
        fibril_mutex_unlock(&vbds_parts_lock);

        vbds_part_del_ref(part);
        part->lpart = NULL;
        fibril_rwlock_write_unlock(&part->lock);

        if (rlpart != NULL)
                *rlpart = lpart;
        return EOK;
}

/** Remove all disk partitions from our inventory leaving only the underlying
 * liblabel partition structures.
 */
static errno_t vbds_disk_parts_add(vbds_disk_t *disk, label_t *label)
{
        label_part_t *part;
        errno_t rc;

        part = label_part_first(label);
        while (part != NULL) {
                rc = vbds_part_add(disk, part, NULL);
                if (rc != EOK) {
                        log_msg(LOG_DEFAULT, LVL_ERROR, "Failed adding partition "
                            "(disk %s)", disk->svc_name);
                        return rc;
                }

                part = label_part_next(part);
        }

        return EOK;
}

/** Remove all disk partitions from our inventory leaving only the underlying
 * liblabel partition structures.
 */
static errno_t vbds_disk_parts_remove(vbds_disk_t *disk, vbds_rem_flag_t flag)
{
        link_t *link;
        vbds_part_t *part;
        errno_t rc;

        link = list_first(&disk->parts);
        while (link != NULL) {
                part = list_get_instance(link, vbds_part_t, ldisk);
                rc = vbds_part_remove(part, flag, NULL);
                if (rc != EOK)
                        return rc;

                link = list_first(&disk->parts);
        }

        return EOK;
}

static void vbds_disk_cat_change_cb(void *arg)
{
        (void) vbds_disks_check_new();
}

errno_t vbds_disk_discovery_start(void)
{
        errno_t rc;

        rc = loc_register_cat_change_cb(vbds_disk_cat_change_cb, NULL);
        if (rc != EOK) {
                log_msg(LOG_DEFAULT, LVL_ERROR, "Failed registering callback "
                    "for disk discovery: %s.", str_error(rc));
                return rc;
        }

        return vbds_disks_check_new();
}

errno_t vbds_disk_add(service_id_t sid)
{
        label_t *label = NULL;
        label_bd_t lbd;
        vbds_disk_t *disk = NULL;
        bool block_inited = false;
        size_t block_size;
        aoff64_t nblocks;
        errno_t rc;

        log_msg(LOG_DEFAULT, LVL_DEBUG, "vbds_disk_add(%zu)", sid);

        /* Check for duplicates */
        rc = vbds_disk_by_svcid(sid, &disk);
        if (rc == EOK)
                return EEXIST;

        disk = calloc(1, sizeof(vbds_disk_t));
        if (disk == NULL)
                return ENOMEM;

        /* Must be set before calling label_open */
        disk->svc_id = sid;

        rc = loc_service_get_name(sid, &disk->svc_name);
        if (rc != EOK) {
                log_msg(LOG_DEFAULT, LVL_ERROR, "Failed getting disk service name.");
                rc = EIO;
                goto error;
        }

        log_msg(LOG_DEFAULT, LVL_DEBUG, "block_init(%zu)", sid);
        rc = block_init(sid, 2048);
        if (rc != EOK) {
                log_msg(LOG_DEFAULT, LVL_ERROR, "Failed opening block device %s.",
                    disk->svc_name);
                rc = EIO;
                goto error;
        }

        rc = block_get_bsize(sid, &block_size);
        if (rc != EOK) {
                log_msg(LOG_DEFAULT, LVL_ERROR, "Failed getting block size of %s.",
                    disk->svc_name);
                rc = EIO;
                goto error;
        }

        rc = block_get_nblocks(sid, &nblocks);
        if (rc != EOK) {
                log_msg(LOG_DEFAULT, LVL_ERROR, "Failed getting number of "
                    "blocks of %s.", disk->svc_name);
                rc = EIO;
                goto error;
        }

        block_inited = true;

        lbd.ops = &vbds_label_bd_ops;
        lbd.arg = (void *) disk;

        rc = label_open(&lbd, &label);
        if (rc != EOK) {
                log_msg(LOG_DEFAULT, LVL_ERROR, "Failed to open label in disk %s.",
                    disk->svc_name);
                rc = EIO;
                goto error;
        }

        disk->label = label;
        disk->block_size = block_size;
        disk->nblocks = nblocks;
        disk->present = true;

        list_initialize(&disk->parts);
        list_append(&disk->ldisks, &vbds_disks);

        log_msg(LOG_DEFAULT, LVL_NOTE, "Recognized disk label. Adding partitions.");

        (void) vbds_disk_parts_add(disk, label);
        return EOK;
error:
        label_close(label);
        if (block_inited) {
                log_msg(LOG_DEFAULT, LVL_DEBUG, "block_fini(%zu)", sid);
                block_fini(sid);
        }
        if (disk != NULL)
                free(disk->svc_name);
        free(disk);
        return rc;
}

errno_t vbds_disk_remove(service_id_t sid)
{
        vbds_disk_t *disk;
        errno_t rc;

        log_msg(LOG_DEFAULT, LVL_DEBUG, "vbds_disk_remove(%zu)", sid);

        rc = vbds_disk_by_svcid(sid, &disk);
        if (rc != EOK)
                return rc;

        rc = vbds_disk_parts_remove(disk, vrf_force);
        if (rc != EOK) {
                log_msg(LOG_DEFAULT, LVL_ERROR, "Failed removing disk.");
                return rc;
        }

        list_remove(&disk->ldisks);
        label_close(disk->label);
        log_msg(LOG_DEFAULT, LVL_DEBUG, "block_fini(%zu)", sid);
        block_fini(sid);
        free(disk);
        return EOK;
}

/** Get list of disks as array of service IDs. */
errno_t vbds_disk_get_ids(service_id_t *id_buf, size_t buf_size, size_t *act_size)
{
        size_t act_cnt;
        size_t buf_cnt;

        fibril_mutex_lock(&vbds_disks_lock);

        buf_cnt = buf_size / sizeof(service_id_t);

        act_cnt = list_count(&vbds_disks);
        *act_size = act_cnt * sizeof(service_id_t);

        if (buf_size % sizeof(service_id_t) != 0) {
                fibril_mutex_unlock(&vbds_disks_lock);
                return EINVAL;
        }

        size_t pos = 0;
        list_foreach(vbds_disks, ldisks, vbds_disk_t, disk) {
                if (pos < buf_cnt)
                        id_buf[pos] = disk->svc_id;
                pos++;
        }

        fibril_mutex_unlock(&vbds_disks_lock);
        return EOK;
}

errno_t vbds_disk_info(service_id_t sid, vbd_disk_info_t *info)
{
        vbds_disk_t *disk;
        label_info_t linfo;
        errno_t rc;

        log_msg(LOG_DEFAULT, LVL_DEBUG, "vbds_disk_info(%zu)", sid);

        rc = vbds_disk_by_svcid(sid, &disk);
        if (rc != EOK)
                return rc;

        rc = label_get_info(disk->label, &linfo);
        if (rc != EOK)
                return rc;

        info->ltype = linfo.ltype;
        info->flags = linfo.flags;
        info->ablock0 = linfo.ablock0;
        info->anblocks = linfo.anblocks;
        info->block_size = disk->block_size;
        info->nblocks = disk->nblocks;
        log_msg(LOG_DEFAULT, LVL_DEBUG, "vbds_disk_info - block_size=%zu",
            info->block_size);
        return EOK;
}

errno_t vbds_get_parts(service_id_t sid, service_id_t *id_buf, size_t buf_size,
    size_t *act_size)
{
        vbds_disk_t *disk;
        size_t act_cnt;
        size_t buf_cnt;
        errno_t rc;

        rc = vbds_disk_by_svcid(sid, &disk);
        if (rc != EOK)
                return rc;

        buf_cnt = buf_size / sizeof(service_id_t);

        act_cnt = list_count(&disk->parts);
        *act_size = act_cnt * sizeof(service_id_t);

        if (buf_size % sizeof(service_id_t) != 0)
                return EINVAL;

        size_t pos = 0;
        list_foreach(disk->parts, ldisk, vbds_part_t, part) {
                if (pos < buf_cnt)
                        id_buf[pos] = part->pid;
                pos++;
        }

        return EOK;
}

errno_t vbds_label_create(service_id_t sid, label_type_t ltype)
{
        label_t *label;
        label_bd_t lbd;
        label_info_t linfo;
        vbds_disk_t *disk;
        errno_t rc, rc2;

        log_msg(LOG_DEFAULT, LVL_DEBUG, "vbds_label_create(%zu)", sid);

        /* Find disk */
        rc = vbds_disk_by_svcid(sid, &disk);
        if (rc != EOK)
                return rc;

        log_msg(LOG_DEFAULT, LVL_DEBUG, "vbds_label_create(%zu) - label_close", sid);

        /* Verify that current label is a dummy label */
        rc = label_get_info(disk->label, &linfo);
        if (rc != EOK)
                return rc;

        if (linfo.ltype != lt_none) {
                log_msg(LOG_DEFAULT, LVL_ERROR, "Label already exists.");
                return EEXIST;
        }

        /* Close dummy label first */
        rc = vbds_disk_parts_remove(disk, vrf_none);
        if (rc != EOK) {
                log_msg(LOG_DEFAULT, LVL_ERROR, "Failed removing disk.");
                return rc;
        }

        label_close(disk->label);
        disk->label = NULL;

        log_msg(LOG_DEFAULT, LVL_DEBUG, "vbds_label_create(%zu) - label_create", sid);

        lbd.ops = &vbds_label_bd_ops;
        lbd.arg = (void *) disk;

        rc = label_create(&lbd, ltype, &label);
        if (rc != EOK)
                goto error;

        (void) vbds_disk_parts_add(disk, label);
        disk->label = label;

        log_msg(LOG_DEFAULT, LVL_DEBUG, "vbds_label_create(%zu) - success", sid);
        return EOK;
error:
        log_msg(LOG_DEFAULT, LVL_DEBUG, "vbds_label_create(%zu) - failure", sid);
        if (disk->label == NULL) {
                lbd.ops = &vbds_label_bd_ops;
                lbd.arg = (void *) disk;

                rc2 = label_open(&lbd, &label);
                if (rc2 != EOK) {
                        log_msg(LOG_DEFAULT, LVL_ERROR, "Failed to open label in disk %s.",
                            disk->svc_name);
                        return rc2;
                }

                disk->label = label;
                (void) vbds_disk_parts_add(disk, label);
        }

        return rc;
}

errno_t vbds_label_delete(service_id_t sid)
{
        vbds_disk_t *disk;
        label_t *label;
        label_bd_t lbd;
        errno_t rc;

        log_msg(LOG_DEFAULT, LVL_DEBUG, "vbds_label_delete(%zu)", sid);

        rc = vbds_disk_by_svcid(sid, &disk);
        if (rc != EOK)
                return rc;

        rc = vbds_disk_parts_remove(disk, vrf_none);
        if (rc != EOK) {
                log_msg(LOG_DEFAULT, LVL_ERROR, "Failed deleting label.");
                return rc;
        }

        rc = label_destroy(disk->label);
        if (rc != EOK) {
                log_msg(LOG_DEFAULT, LVL_ERROR, "Failed deleting label.");
                return rc;
        }

        disk->label = NULL;

        lbd.ops = &vbds_label_bd_ops;
        lbd.arg = (void *) disk;

        rc = label_open(&lbd, &label);
        if (rc != EOK) {
                log_msg(LOG_DEFAULT, LVL_ERROR, "Failed to open label in disk %s.",
                    disk->svc_name);
                return EIO;
        }

        (void) vbds_disk_parts_add(disk, label);
        disk->label = label;
        return EOK;
}

errno_t vbds_part_get_info(vbds_part_id_t partid, vbd_part_info_t *pinfo)
{
        vbds_part_t *part;
        label_part_info_t lpinfo;
        errno_t rc;

        rc = vbds_part_by_pid(partid, &part);
        if (rc != EOK)
                return rc;

        fibril_rwlock_read_lock(&part->lock);
        if (part->lpart == NULL) {
                fibril_rwlock_read_unlock(&part->lock);
                return ENOENT;
        }

        label_part_get_info(part->lpart, &lpinfo);

        pinfo->index = lpinfo.index;
        pinfo->pkind = lpinfo.pkind;
        pinfo->block0 = lpinfo.block0;
        pinfo->nblocks = lpinfo.nblocks;
        pinfo->svc_id = part->svc_id;
        vbds_part_del_ref(part);
        fibril_rwlock_read_unlock(&part->lock);

        return EOK;
}

errno_t vbds_part_create(service_id_t sid, vbd_part_spec_t *pspec,
    vbds_part_id_t *rpart)
{
        vbds_disk_t *disk;
        vbds_part_t *part;
        label_part_spec_t lpspec;
        label_part_t *lpart;
        errno_t rc;

        log_msg(LOG_DEFAULT, LVL_DEBUG, "vbds_part_create(%zu)", sid);

        rc = vbds_disk_by_svcid(sid, &disk);
        if (rc != EOK) {
                log_msg(LOG_DEFAULT, LVL_ERROR, "Disk %zu not found",
                    sid);
                goto error;
        }

        log_msg(LOG_DEFAULT, LVL_DEBUG, "vbds_part_crate(%zu): "
            "index=%d block0=%" PRIu64 " nblocks=%" PRIu64
            " hdr_blocks=%" PRIu64 " pkind=%d",
            sid, pspec->index, pspec->block0, pspec->nblocks, pspec->hdr_blocks,
            pspec->pkind);

        label_pspec_init(&lpspec);
        lpspec.index = pspec->index;
        lpspec.block0 = pspec->block0;
        lpspec.nblocks = pspec->nblocks;
        lpspec.hdr_blocks = pspec->hdr_blocks;
        lpspec.pkind = pspec->pkind;
        lpspec.ptype = pspec->ptype;

        rc = label_part_create(disk->label, &lpspec, &lpart);
        if (rc != EOK) {
                log_msg(LOG_DEFAULT, LVL_ERROR, "Error creating partition.");
                goto error;
        }

        rc = label_part_empty(lpart);
        if (rc != EOK) {
                log_msg(LOG_DEFAULT, LVL_ERROR, "Error emptying partition.");
                goto error;
        }

        rc = vbds_part_indices_update(disk);
        if (rc != EOK) {
                log_msg(LOG_DEFAULT, LVL_ERROR, "Error updating partition indices");
                goto error;
        }

        rc = vbds_part_add(disk, lpart, &part);
        if (rc != EOK) {
                log_msg(LOG_DEFAULT, LVL_ERROR, "Failed while creating "
                    "partition.");
                rc = label_part_destroy(lpart);
                if (rc != EOK)
                        log_msg(LOG_DEFAULT, LVL_ERROR,
                            "Cannot roll back partition creation.");
                rc = EIO;
                goto error;
        }

        if (rpart != NULL)
                *rpart = part->pid;
        return EOK;
error:
        return rc;
}

errno_t vbds_part_delete(vbds_part_id_t partid)
{
        vbds_part_t *part;
        vbds_disk_t *disk;
        label_part_t *lpart;
        errno_t rc;

        rc = vbds_part_by_pid(partid, &part);
        if (rc != EOK)
                return rc;

        disk = part->disk;

        rc = vbds_part_remove(part, vrf_none, &lpart);
        if (rc != EOK)
                return rc;

        rc = label_part_destroy(lpart);
        vbds_part_del_ref(part);
        if (rc != EOK) {
                log_msg(LOG_DEFAULT, LVL_ERROR, "Failed deleting partition");

                /* Try rolling back */
                rc = vbds_part_add(disk, lpart, NULL);
                if (rc != EOK)
                        log_msg(LOG_DEFAULT, LVL_ERROR, "Failed rolling back.");

                return EIO;
        }

        rc = vbds_part_indices_update(disk);
        if (rc != EOK) {
                log_msg(LOG_DEFAULT, LVL_ERROR, "Error updating partition indices");
                return EIO;
        }

        return EOK;
}

errno_t vbds_suggest_ptype(service_id_t sid, label_pcnt_t pcnt,
    label_ptype_t *ptype)
{
        vbds_disk_t *disk;
        errno_t rc;

        rc = vbds_disk_by_svcid(sid, &disk);
        if (rc != EOK) {
                log_msg(LOG_DEFAULT, LVL_DEBUG, "Disk %zu not found",
                    sid);
                goto error;
        }

        rc = label_suggest_ptype(disk->label, pcnt, ptype);
        if (rc != EOK) {
                log_msg(LOG_DEFAULT, LVL_DEBUG, "label_suggest_ptype() failed");
                goto error;
        }

        return EOK;
error:
        return rc;
}

static errno_t vbds_bd_open(bd_srvs_t *bds, bd_srv_t *bd)
{
        vbds_part_t *part = bd_srv_part(bd);

        log_msg(LOG_DEFAULT, LVL_DEBUG, "vbds_bd_open()");
        fibril_rwlock_write_lock(&part->lock);
        part->open_cnt++;
        fibril_rwlock_write_unlock(&part->lock);
        return EOK;
}

static errno_t vbds_bd_close(bd_srv_t *bd)
{
        vbds_part_t *part = bd_srv_part(bd);

        log_msg(LOG_DEFAULT, LVL_DEBUG, "vbds_bd_close()");

        /* Grabbing writer lock also forces all I/O to complete */

        fibril_rwlock_write_lock(&part->lock);
        part->open_cnt--;
        fibril_rwlock_write_unlock(&part->lock);
        return EOK;
}

static errno_t vbds_bd_read_blocks(bd_srv_t *bd, aoff64_t ba, size_t cnt,
    void *buf, size_t size)
{
        vbds_part_t *part = bd_srv_part(bd);
        aoff64_t gba;
        errno_t rc;

        log_msg(LOG_DEFAULT, LVL_DEBUG2, "vbds_bd_read_blocks()");
        fibril_rwlock_read_lock(&part->lock);

        if (cnt * part->disk->block_size < size) {
                fibril_rwlock_read_unlock(&part->lock);
                return EINVAL;
        }

        if (vbds_bsa_translate(part, ba, cnt, &gba) != EOK) {
                fibril_rwlock_read_unlock(&part->lock);
                return ELIMIT;
        }

        rc = block_read_direct(part->disk->svc_id, gba, cnt, buf);
        fibril_rwlock_read_unlock(&part->lock);

        return rc;
}

static errno_t vbds_bd_sync_cache(bd_srv_t *bd, aoff64_t ba, size_t cnt)
{
        vbds_part_t *part = bd_srv_part(bd);
        aoff64_t gba;
        errno_t rc;

        log_msg(LOG_DEFAULT, LVL_DEBUG2, "vbds_bd_sync_cache()");
        fibril_rwlock_read_lock(&part->lock);

        /* XXX Allow full-disk sync? */
        if (ba != 0 || cnt != 0) {
                if (vbds_bsa_translate(part, ba, cnt, &gba) != EOK) {
                        fibril_rwlock_read_unlock(&part->lock);
                        return ELIMIT;
                }
        } else {
                gba = 0;
        }

        rc = block_sync_cache(part->disk->svc_id, gba, cnt);
        fibril_rwlock_read_unlock(&part->lock);
        return rc;
}

static errno_t vbds_bd_write_blocks(bd_srv_t *bd, aoff64_t ba, size_t cnt,
    const void *buf, size_t size)
{
        vbds_part_t *part = bd_srv_part(bd);
        aoff64_t gba;
        errno_t rc;

        log_msg(LOG_DEFAULT, LVL_DEBUG2, "vbds_bd_write_blocks()");
        fibril_rwlock_read_lock(&part->lock);

        if (cnt * part->disk->block_size < size) {
                fibril_rwlock_read_unlock(&part->lock);
                return EINVAL;
        }

        if (vbds_bsa_translate(part, ba, cnt, &gba) != EOK) {
                fibril_rwlock_read_unlock(&part->lock);
                return ELIMIT;
        }

        rc = block_write_direct(part->disk->svc_id, gba, cnt, buf);
        fibril_rwlock_read_unlock(&part->lock);
        return rc;
}

static errno_t vbds_bd_get_block_size(bd_srv_t *bd, size_t *rsize)
{
        vbds_part_t *part = bd_srv_part(bd);

        log_msg(LOG_DEFAULT, LVL_DEBUG2, "vbds_bd_get_block_size()");

        fibril_rwlock_read_lock(&part->lock);
        *rsize = part->disk->block_size;
        fibril_rwlock_read_unlock(&part->lock);

        return EOK;
}

static errno_t vbds_bd_get_num_blocks(bd_srv_t *bd, aoff64_t *rnb)
{
        vbds_part_t *part = bd_srv_part(bd);

        log_msg(LOG_DEFAULT, LVL_DEBUG2, "vbds_bd_get_num_blocks()");

        fibril_rwlock_read_lock(&part->lock);
        *rnb = part->nblocks;
        fibril_rwlock_read_unlock(&part->lock);

        return EOK;
}

void vbds_bd_conn(ipc_call_t *icall, void *arg)
{
        vbds_part_t *part;
        errno_t rc;
        service_id_t svcid;

        log_msg(LOG_DEFAULT, LVL_DEBUG, "vbds_bd_conn()");

        svcid = ipc_get_arg2(icall);

        log_msg(LOG_DEFAULT, LVL_DEBUG, "vbds_bd_conn() - svcid=%zu", svcid);

        rc = vbds_part_by_svcid(svcid, &part);
        if (rc != EOK) {
                log_msg(LOG_DEFAULT, LVL_DEBUG, "vbd_bd_conn() - partition "
                    "not found.");
                async_answer_0(icall, EINVAL);
                return;
        }

        log_msg(LOG_DEFAULT, LVL_DEBUG, "vbds_bd_conn() - call bd_conn");
        bd_conn(icall, &part->bds);
        vbds_part_del_ref(part);
}

/** Translate block segment address with range checking. */
static errno_t vbds_bsa_translate(vbds_part_t *part, aoff64_t ba, size_t cnt,
    aoff64_t *gba)
{
        if (ba + cnt > part->nblocks)
                return ELIMIT;

        *gba = part->block0 + ba;
        return EOK;
}

/** Register service for partition */
static errno_t vbds_part_svc_register(vbds_part_t *part)
{
        char *name;
        service_id_t psid;
        int idx;
        errno_t rc;

        idx = part->lpart->index;

        if (asprintf(&name, "%sp%u", part->disk->svc_name, idx) < 0) {
                log_msg(LOG_DEFAULT, LVL_ERROR, "Out of memory.");
                return ENOMEM;
        }

        log_msg(LOG_DEFAULT, LVL_DEBUG, "loc_service_register('%s')",
            name);
        rc = loc_service_register(vbds_srv, name, &psid);
        if (rc != EOK) {
                log_msg(LOG_DEFAULT, LVL_ERROR, "Failed registering "
                    "service %s: %s.", name, str_error(rc));
                free(name);
                free(part);
                return EIO;
        }

        rc = loc_service_add_to_cat(vbds_srv, psid, part_cid);
        if (rc != EOK) {
                log_msg(LOG_DEFAULT, LVL_ERROR, "Failled adding partition "
                    "service %s to partition category.", name);
                free(name);
                free(part);

                rc = loc_service_unregister(vbds_srv, psid);
                if (rc != EOK) {
                        log_msg(LOG_DEFAULT, LVL_ERROR, "Error unregistering "
                            "service. Rollback failed.");
                }
                return EIO;
        }

        free(name);
        part->svc_id = psid;
        part->reg_idx = idx;
        return EOK;
}

/** Unregister service for partition */
static errno_t vbds_part_svc_unregister(vbds_part_t *part)
{
        errno_t rc;

        log_msg(LOG_DEFAULT, LVL_DEBUG, "vbds_part_svc_unregister("
            "disk->svc_name='%s', id=%zu)", part->disk->svc_name, part->svc_id);

        rc = loc_service_unregister(vbds_srv, part->svc_id);
        if (rc != EOK)
                return EIO;

        part->svc_id = 0;
        part->reg_idx = 0;
        return EOK;
}

/** Update service names for any partition whose index has changed. */
static errno_t vbds_part_indices_update(vbds_disk_t *disk)
{
        label_part_info_t lpinfo;
        errno_t rc;

        log_msg(LOG_DEFAULT, LVL_DEBUG, "vbds_part_indices_update()");

        fibril_mutex_lock(&vbds_parts_lock);

        /* First unregister services for partitions whose index has changed */
        list_foreach(disk->parts, ldisk, vbds_part_t, part) {
                fibril_rwlock_write_lock(&part->lock);
                if (part->svc_id != 0 && part->lpart->index != part->reg_idx) {
                        rc = vbds_part_svc_unregister(part);
                        if (rc != EOK) {
                                fibril_rwlock_write_unlock(&part->lock);
                                fibril_mutex_unlock(&vbds_parts_lock);
                                log_msg(LOG_DEFAULT, LVL_ERROR, "Error "
                                    "un-registering partition.");
                                return EIO;
                        }
                }

                fibril_rwlock_write_unlock(&part->lock);
        }

        /* Now re-register those services under the new indices */
        list_foreach(disk->parts, ldisk, vbds_part_t, part) {
                fibril_rwlock_write_lock(&part->lock);
                label_part_get_info(part->lpart, &lpinfo);
                if (part->svc_id == 0 && lpinfo.pkind != lpk_extended) {
                        rc = vbds_part_svc_register(part);
                        if (rc != EOK) {
                                fibril_rwlock_write_unlock(&part->lock);
                                fibril_mutex_unlock(&vbds_parts_lock);
                                log_msg(LOG_DEFAULT, LVL_ERROR, "Error "
                                    "re-registering partition.");
                                return EIO;
                        }
                }

                fibril_rwlock_write_unlock(&part->lock);
        }

        fibril_mutex_unlock(&vbds_parts_lock);

        return EOK;
}

/** Get block size wrapper for liblabel */
static errno_t vbds_label_get_bsize(void *arg, size_t *bsize)
{
        vbds_disk_t *disk = (vbds_disk_t *)arg;
        return block_get_bsize(disk->svc_id, bsize);
}

/** Get number of blocks wrapper for liblabel */
static errno_t vbds_label_get_nblocks(void *arg, aoff64_t *nblocks)
{
        vbds_disk_t *disk = (vbds_disk_t *)arg;
        return block_get_nblocks(disk->svc_id, nblocks);
}

/** Read blocks wrapper for liblabel */
static errno_t vbds_label_read(void *arg, aoff64_t ba, size_t cnt, void *buf)
{
        vbds_disk_t *disk = (vbds_disk_t *)arg;
        return block_read_direct(disk->svc_id, ba, cnt, buf);
}

/** Write blocks wrapper for liblabel */
static errno_t vbds_label_write(void *arg, aoff64_t ba, size_t cnt, const void *data)
{
        vbds_disk_t *disk = (vbds_disk_t *)arg;
        return block_write_direct(disk->svc_id, ba, cnt, data);
}

/** @}
 */