source: mainline/uspace/srv/volsrv/part.c@ 40340461

/*
 * Copyright (c) 2015 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 volsrv
 * @{
 */
/**
 * @file Partition handling
 * @brief
 */

#include <stdbool.h>
#include <errno.h>
#include <str_error.h>
#include <fibril_synch.h>
#include <io/log.h>
#include <loc.h>
#include <stdlib.h>
#include <str.h>
#include <vfs/vfs.h>

#include "empty.h"
#include "mkfs.h"
#include "part.h"
#include "types/part.h"

static errno_t vol_part_add_locked(service_id_t);
static void vol_part_remove_locked(vol_part_t *);
static errno_t vol_part_find_by_id_ref_locked(service_id_t, vol_part_t **);

static LIST_INITIALIZE(vol_parts); /* of vol_part_t */
static FIBRIL_MUTEX_INITIALIZE(vol_parts_lock);

struct fsname_type {
        const char *name;
        vol_fstype_t fstype;
};

static struct fsname_type fstab[] = {
        { "ext4fs", fs_ext4 },
        { "cdfs", fs_cdfs },
        { "exfat", fs_exfat },
        { "fat", fs_fat },
        { "mfs", fs_minix },
        { NULL, 0 }
};

static const char *fstype_str(vol_fstype_t fstype)
{
        struct fsname_type *fst;

        fst = &fstab[0];
        while (fst->name != NULL) {
                if (fst->fstype == fstype)
                        return fst->name;
                ++fst;
        }

        assert(false);
        return NULL;
}

/** Check for new and removed partitions */
static errno_t vol_part_check_new(void)
{
        bool already_known;
        bool still_exists;
        category_id_t part_cat;
        service_id_t *svcs;
        size_t count, i;
        link_t *cur, *next;
        vol_part_t *part;
        errno_t rc;

        fibril_mutex_lock(&vol_parts_lock);

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

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

        /* Check for new partitions */
        for (i = 0; i < count; i++) {
                already_known = false;

                // XXX Make this faster
                list_foreach(vol_parts, lparts, vol_part_t, part) {
                        if (part->svc_id == svcs[i]) {
                                already_known = true;
                                break;
                        }
                }

                if (!already_known) {
                        log_msg(LOG_DEFAULT, LVL_NOTE, "Found partition '%lu'",
                            (unsigned long) svcs[i]);
                        rc = vol_part_add_locked(svcs[i]);
                        if (rc != EOK) {
                                log_msg(LOG_DEFAULT, LVL_ERROR, "Could not add "
                                    "partition.");
                        }
                }
        }

        /* Check for removed partitions */
        cur = list_first(&vol_parts);
        while (cur != NULL) {
                next = list_next(cur, &vol_parts);
                part = list_get_instance(cur, vol_part_t, lparts);

                still_exists = false;
                // XXX Make this faster
                for (i = 0; i < count; i++) {
                        if (part->svc_id == svcs[i]) {
                                still_exists = true;
                                break;
                        }
                }

                if (!still_exists) {
                        log_msg(LOG_DEFAULT, LVL_NOTE, "Partition '%zu' is gone",
                            part->svc_id);
                        vol_part_remove_locked(part);
                }

                cur = next;
        }

        free(svcs);

        fibril_mutex_unlock(&vol_parts_lock);
        return EOK;
}

static vol_part_t *vol_part_new(void)
{
        vol_part_t *part = calloc(1, sizeof(vol_part_t));

        if (part == NULL) {
                log_msg(LOG_DEFAULT, LVL_ERROR, "Failed allocating partition "
                    "structure. Out of memory.");
                return NULL;
        }

        atomic_set(&part->refcnt, 1);
        link_initialize(&part->lparts);
        part->pcnt = vpc_empty;

        return part;
}

static void vol_part_delete(vol_part_t *part)
{
        log_msg(LOG_DEFAULT, LVL_ERROR, "Freeing partition %p", part);
        if (part == NULL)
                return;

        free(part->cur_mp);
        free(part->svc_name);
        free(part);
}

static errno_t vol_part_probe(vol_part_t *part)
{
        bool empty;
        vfs_fs_probe_info_t info;
        struct fsname_type *fst;
        char *label;
        errno_t rc;

        log_msg(LOG_DEFAULT, LVL_NOTE, "Probe partition %s", part->svc_name);

        assert(fibril_mutex_is_locked(&vol_parts_lock));

        fst = &fstab[0];
        while (fst->name != NULL) {
                rc = vfs_fsprobe(fst->name, part->svc_id, &info);
                if (rc == EOK)
                        break;
                ++fst;
        }

        if (fst->name != NULL) {
                log_msg(LOG_DEFAULT, LVL_NOTE, "Found %s, label '%s'",
                    fst->name, info.label);
                label = str_dup(info.label);
                if (label == NULL) {
                        rc = ENOMEM;
                        goto error;
                }

                part->pcnt = vpc_fs;
                part->fstype = fst->fstype;
                part->label = label;
        } else {
                log_msg(LOG_DEFAULT, LVL_NOTE, "Partition does not contain "
                    "a recognized file system.");

                rc = volsrv_part_is_empty(part->svc_id, &empty);
                if (rc != EOK) {
                        log_msg(LOG_DEFAULT, LVL_ERROR, "Failed determining if "
                            "partition is empty.");
                        rc = EIO;
                        goto error;
                }

                label = str_dup("");
                if (label == NULL) {
                        rc = ENOMEM;
                        goto error;
                }

                part->pcnt = empty ? vpc_empty : vpc_unknown;
                part->label = label;
        }

        return EOK;

error:
        return rc;
}

static errno_t vol_part_mount(vol_part_t *part)
{
        char *mp;
        int err;
        errno_t rc;

        if (str_size(part->label) < 1) {
                /* Don't mount nameless volumes */
                log_msg(LOG_DEFAULT, LVL_NOTE, "Not mounting nameless partition.");
                return EOK;
        }

        log_msg(LOG_DEFAULT, LVL_NOTE, "Determine MP label='%s'", part->label);
        err = asprintf(&mp, "/vol/%s", part->label);
        if (err < 0) {
                log_msg(LOG_DEFAULT, LVL_ERROR, "Out of memory");
                return ENOMEM;
        }

        log_msg(LOG_DEFAULT, LVL_NOTE, "Create mount point '%s'", mp);
        rc = vfs_link_path(mp, KIND_DIRECTORY, NULL);
        if (rc != EOK) {
                log_msg(LOG_DEFAULT, LVL_ERROR, "Error creating mount point '%s'",
                    mp);
                free(mp);
                return EIO;
        }

        log_msg(LOG_DEFAULT, LVL_NOTE, "Call vfs_mount_path mp='%s' fstype='%s' svc_name='%s'",
            mp, fstype_str(part->fstype), part->svc_name);
        rc = vfs_mount_path(mp, fstype_str(part->fstype),
            part->svc_name, "", 0, 0);
        if (rc != EOK) {
                log_msg(LOG_DEFAULT, LVL_NOTE, "Failed mounting to %s", mp);
        }
        log_msg(LOG_DEFAULT, LVL_NOTE, "Mount to %s -> %d\n", mp, rc);

        part->cur_mp = mp;
        part->cur_mp_auto = true;

        return rc;
}

static errno_t vol_part_add_locked(service_id_t sid)
{
        vol_part_t *part;
        errno_t rc;

        assert(fibril_mutex_is_locked(&vol_parts_lock));
        log_msg(LOG_DEFAULT, LVL_NOTE, "vol_part_add_locked(%zu)", sid);

        /* Check for duplicates */
        rc = vol_part_find_by_id_ref_locked(sid, &part);
        if (rc == EOK) {
                vol_part_del_ref(part);
                return EEXIST;
        }

        log_msg(LOG_DEFAULT, LVL_NOTE, "partition %zu is new", sid);

        part = vol_part_new();
        if (part == NULL)
                return ENOMEM;

        part->svc_id = sid;

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

        rc = vol_part_probe(part);
        if (rc != EOK)
                goto error;

        rc = vol_part_mount(part);
        if (rc != EOK)
                goto error;

        list_append(&part->lparts, &vol_parts);

        log_msg(LOG_DEFAULT, LVL_NOTE, "Added partition %zu", part->svc_id);

        return EOK;

error:
        vol_part_delete(part);
        return rc;
}

static void vol_part_remove_locked(vol_part_t *part)
{
        assert(fibril_mutex_is_locked(&vol_parts_lock));
        log_msg(LOG_DEFAULT, LVL_NOTE, "vol_part_remove_locked(%zu)", part->svc_id);

        list_remove(&part->lparts);

        log_msg(LOG_DEFAULT, LVL_NOTE, "Removed partition.");
        vol_part_del_ref(part);
}

errno_t vol_part_add(service_id_t sid)
{
        errno_t rc;

        fibril_mutex_lock(&vol_parts_lock);
        rc = vol_part_add_locked(sid);
        fibril_mutex_unlock(&vol_parts_lock);

        return rc;
}

static void vol_part_cat_change_cb(void)
{
        (void) vol_part_check_new();
}

errno_t vol_part_init(void)
{
        return EOK;
}

errno_t vol_part_discovery_start(void)
{
        errno_t rc;

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

        return vol_part_check_new();
}

/** Get list of partitions as array of service IDs. */
errno_t vol_part_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(&vol_parts_lock);

        buf_cnt = buf_size / sizeof(service_id_t);

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

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

        size_t pos = 0;
        list_foreach(vol_parts, lparts, vol_part_t, part) {
                if (pos < buf_cnt)
                        id_buf[pos] = part->svc_id;
                pos++;
        }

        fibril_mutex_unlock(&vol_parts_lock);
        return EOK;
}

static errno_t vol_part_find_by_id_ref_locked(service_id_t sid,
    vol_part_t **rpart)
{
        assert(fibril_mutex_is_locked(&vol_parts_lock));

        list_foreach(vol_parts, lparts, vol_part_t, part) {
                if (part->svc_id == sid) {
                        /* Add reference */
                        atomic_inc(&part->refcnt);
                        *rpart = part;
                        return EOK;
                }
        }

        return ENOENT;
}

errno_t vol_part_find_by_id_ref(service_id_t sid, vol_part_t **rpart)
{
        errno_t rc;

        fibril_mutex_lock(&vol_parts_lock);
        rc = vol_part_find_by_id_ref_locked(sid, rpart);
        fibril_mutex_unlock(&vol_parts_lock);

        return rc;
}

void vol_part_del_ref(vol_part_t *part)
{
        if (atomic_predec(&part->refcnt) == 0)
                vol_part_delete(part);
}

errno_t vol_part_eject_part(vol_part_t *part)
{
        int rc;

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

        if (part->cur_mp == NULL) {
                log_msg(LOG_DEFAULT, LVL_DEBUG, "Attempt to mount unmounted "
                    "partition.");
                return EINVAL;
        }

        rc = vfs_unmount_path(part->cur_mp);
        if (rc != EOK) {
                log_msg(LOG_DEFAULT, LVL_ERROR, "Failed unmounting partition "
                    "from %s", part->cur_mp);
                return rc;
        }

        if (part->cur_mp_auto) {
                rc = vfs_unlink_path(part->cur_mp);
                if (rc != EOK) {
                        log_msg(LOG_DEFAULT, LVL_ERROR, "Failed deleting "
                            "mount directory %s.", part->cur_mp);
                }
        }

        free(part->cur_mp);
        part->cur_mp = NULL;
        part->cur_mp_auto = false;

        return EOK;
}

errno_t vol_part_empty_part(vol_part_t *part)
{
        errno_t rc;

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

        rc = volsrv_part_empty(part->svc_id);
        if (rc != EOK) {
                log_msg(LOG_DEFAULT, LVL_DEBUG, "vol_part_empty_part() - failed %s",
                    str_error(rc));
                return rc;
        }

        part->pcnt = vpc_empty;
        return EOK;
}

errno_t vol_part_mkfs_part(vol_part_t *part, vol_fstype_t fstype,
    const char *label)
{
        errno_t rc;

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

        fibril_mutex_lock(&vol_parts_lock);

        rc = volsrv_part_mkfs(part->svc_id, fstype, label);
        if (rc != EOK) {
                log_msg(LOG_DEFAULT, LVL_DEBUG, "vol_part_mkfs_part() - failed %s",
                    str_error(rc));
                fibril_mutex_unlock(&vol_parts_lock);
                return rc;
        }

        /*
         * Re-probe the partition to update information. This is needed since
         * the FS can make conversions of the volume label (e.g. make it
         * uppercase).
         */
        rc = vol_part_probe(part);
        if (rc != EOK) {
                fibril_mutex_unlock(&vol_parts_lock);
                return rc;
        }

        rc = vol_part_mount(part);
        if (rc != EOK) {
                fibril_mutex_unlock(&vol_parts_lock);
                return rc;
        }

        fibril_mutex_unlock(&vol_parts_lock);
        return EOK;
}

errno_t vol_part_get_info(vol_part_t *part, vol_part_info_t *pinfo)
{
        memset(pinfo, 0, sizeof(*pinfo));

        pinfo->pcnt = part->pcnt;
        pinfo->fstype = part->fstype;
        str_cpy(pinfo->label, sizeof(pinfo->label), part->label);
        if (part->cur_mp != NULL)
                str_cpy(pinfo->cur_mp, sizeof(pinfo->cur_mp), part->cur_mp);
        pinfo->cur_mp_auto = part->cur_mp_auto;
        return EOK;
}

/** @}
 */