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root/fs/gfs2/locking/dlm/mount.c

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DEFINITIONS

This source file includes following definitions.
  1. init_gdlm
  2. make_args
  3. gdlm_mount
  4. gdlm_unmount
  5. gdlm_recovery_done
  6. gdlm_others_may_mount
  7. gdlm_withdraw
  8. gdlm_plock
  9. gdlm_punlock
  10. gdlm_plock_get

/*
 * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
 * Copyright (C) 2004-2005 Red Hat, Inc.  All rights reserved.
 *
 * This copyrighted material is made available to anyone wishing to use,
 * modify, copy, or redistribute it subject to the terms and conditions
 * of the GNU General Public License version 2.
 */

#include "lock_dlm.h"

const struct lm_lockops gdlm_ops;


static struct gdlm_ls *init_gdlm(lm_callback_t cb, struct gfs2_sbd *sdp,
                                 int flags, char *table_name)
{
        struct gdlm_ls *ls;
        char buf[256], *p;

        ls = kzalloc(sizeof(struct gdlm_ls), GFP_KERNEL);
        if (!ls)
                return NULL;

        ls->fscb = cb;
        ls->sdp = sdp;
        ls->fsflags = flags;
        spin_lock_init(&ls->async_lock);
        INIT_LIST_HEAD(&ls->delayed);
        INIT_LIST_HEAD(&ls->submit);
        init_waitqueue_head(&ls->thread_wait);
        init_waitqueue_head(&ls->wait_control);
        ls->jid = -1;

        strncpy(buf, table_name, 256);
        buf[255] = '\0';

        p = strchr(buf, ':');
        if (!p) {
                log_info("invalid table_name \"%s\"", table_name);
                kfree(ls);
                return NULL;
        }
        *p = '\0';
        p++;

        strncpy(ls->clustername, buf, GDLM_NAME_LEN);
        strncpy(ls->fsname, p, GDLM_NAME_LEN);

        return ls;
}

static int make_args(struct gdlm_ls *ls, char *data_arg, int *nodir)
{
        char data[256];
        char *options, *x, *y;
        int error = 0;

        memset(data, 0, 256);
        strncpy(data, data_arg, 255);

        if (!strlen(data)) {
                log_error("no mount options, (u)mount helpers not installed");
                return -EINVAL;
        }

        for (options = data; (x = strsep(&options, ":")); ) {
                if (!*x)
                        continue;

                y = strchr(x, '=');
                if (y)
                        *y++ = 0;

                if (!strcmp(x, "jid")) {
                        if (!y) {
                                log_error("need argument to jid");
                                error = -EINVAL;
                                break;
                        }
                        sscanf(y, "%u", &ls->jid);

                } else if (!strcmp(x, "first")) {
                        if (!y) {
                                log_error("need argument to first");
                                error = -EINVAL;
                                break;
                        }
                        sscanf(y, "%u", &ls->first);

                } else if (!strcmp(x, "id")) {
                        if (!y) {
                                log_error("need argument to id");
                                error = -EINVAL;
                                break;
                        }
                        sscanf(y, "%u", &ls->id);

                } else if (!strcmp(x, "nodir")) {
                        if (!y) {
                                log_error("need argument to nodir");
                                error = -EINVAL;
                                break;
                        }
                        sscanf(y, "%u", nodir);

                } else {
                        log_error("unkonwn option: %s", x);
                        error = -EINVAL;
                        break;
                }
        }

        return error;
}

static int gdlm_mount(char *table_name, char *host_data,
                        lm_callback_t cb, void *cb_data,
                        unsigned int min_lvb_size, int flags,
                        struct lm_lockstruct *lockstruct,
                        struct kobject *fskobj)
{
        struct gdlm_ls *ls;
        int error = -ENOMEM, nodir = 0;

        if (min_lvb_size > GDLM_LVB_SIZE)
                goto out;

        ls = init_gdlm(cb, cb_data, flags, table_name);
        if (!ls)
                goto out;

        error = make_args(ls, host_data, &nodir);
        if (error)
                goto out;

        error = gdlm_init_threads(ls);
        if (error)
                goto out_free;

        error = gdlm_kobject_setup(ls, fskobj);
        if (error)
                goto out_thread;

        error = dlm_new_lockspace(ls->fsname, strlen(ls->fsname),
                                  &ls->dlm_lockspace,
                                  DLM_LSFL_FS | DLM_LSFL_NEWEXCL |
                                  (nodir ? DLM_LSFL_NODIR : 0),
                                  GDLM_LVB_SIZE);
        if (error) {
                log_error("dlm_new_lockspace error %d", error);
                goto out_kobj;
        }

        lockstruct->ls_jid = ls->jid;
        lockstruct->ls_first = ls->first;
        lockstruct->ls_lockspace = ls;
        lockstruct->ls_ops = &gdlm_ops;
        lockstruct->ls_flags = 0;
        lockstruct->ls_lvb_size = GDLM_LVB_SIZE;
        return 0;

out_kobj:
        gdlm_kobject_release(ls);
out_thread:
        gdlm_release_threads(ls);
out_free:
        kfree(ls);
out:
        return error;
}

static void gdlm_unmount(void *lockspace)
{
        struct gdlm_ls *ls = lockspace;

        log_debug("unmount flags %lx", ls->flags);

        /* FIXME: serialize unmount and withdraw in case they
           happen at once.  Also, if unmount follows withdraw,
           wait for withdraw to finish. */

        if (test_bit(DFL_WITHDRAW, &ls->flags))
                goto out;

        gdlm_kobject_release(ls);
        dlm_release_lockspace(ls->dlm_lockspace, 2);
        gdlm_release_threads(ls);
        BUG_ON(ls->all_locks_count);
out:
        kfree(ls);
}

static void gdlm_recovery_done(void *lockspace, unsigned int jid,
                               unsigned int message)
{
        struct gdlm_ls *ls = lockspace;
        ls->recover_jid_done = jid;
        ls->recover_jid_status = message;
        kobject_uevent(&ls->kobj, KOBJ_CHANGE);
}

static void gdlm_others_may_mount(void *lockspace)
{
        struct gdlm_ls *ls = lockspace;
        ls->first_done = 1;
        kobject_uevent(&ls->kobj, KOBJ_CHANGE);
}

/* Userspace gets the offline uevent, blocks new gfs locks on
   other mounters, and lets us know (sets WITHDRAW flag).  Then,
   userspace leaves the mount group while we leave the lockspace. */

static void gdlm_withdraw(void *lockspace)
{
        struct gdlm_ls *ls = lockspace;

        kobject_uevent(&ls->kobj, KOBJ_OFFLINE);

        wait_event_interruptible(ls->wait_control,
                                 test_bit(DFL_WITHDRAW, &ls->flags));

        dlm_release_lockspace(ls->dlm_lockspace, 2);
        gdlm_release_threads(ls);
        gdlm_kobject_release(ls);
}

static int gdlm_plock(void *lockspace, struct lm_lockname *name,
               struct file *file, int cmd, struct file_lock *fl)
{
        struct gdlm_ls *ls = lockspace;
        return dlm_posix_lock(ls->dlm_lockspace, name->ln_number, file, cmd, fl);
}

static int gdlm_punlock(void *lockspace, struct lm_lockname *name,
                 struct file *file, struct file_lock *fl)
{
        struct gdlm_ls *ls = lockspace;
        return dlm_posix_unlock(ls->dlm_lockspace, name->ln_number, file, fl);
}

static int gdlm_plock_get(void *lockspace, struct lm_lockname *name,
                   struct file *file, struct file_lock *fl)
{
        struct gdlm_ls *ls = lockspace;
        return dlm_posix_get(ls->dlm_lockspace, name->ln_number, file, fl);
}

const struct lm_lockops gdlm_ops = {
        .lm_proto_name = "lock_dlm",
        .lm_mount = gdlm_mount,
        .lm_others_may_mount = gdlm_others_may_mount,
        .lm_unmount = gdlm_unmount,
        .lm_withdraw = gdlm_withdraw,
        .lm_get_lock = gdlm_get_lock,
        .lm_put_lock = gdlm_put_lock,
        .lm_lock = gdlm_lock,
        .lm_unlock = gdlm_unlock,
        .lm_plock = gdlm_plock,
        .lm_punlock = gdlm_punlock,
        .lm_plock_get = gdlm_plock_get,
        .lm_cancel = gdlm_cancel,
        .lm_hold_lvb = gdlm_hold_lvb,
        .lm_unhold_lvb = gdlm_unhold_lvb,
        .lm_recovery_done = gdlm_recovery_done,
        .lm_owner = THIS_MODULE,
};


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