/*
 * GPL HEADER START
 *
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 only,
 * as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License version 2 for more details (a copy is included
 * in the LICENSE file that accompanied this code).
 *
 * You should have received a copy of the GNU General Public License
 * version 2 along with this program; If not, see
 * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
 *
 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
 * CA 95054 USA or visit www.sun.com if you need additional information or
 * have any questions.
 *
 * GPL HEADER END
 */
/*
 * Copyright (c) 2004, 2010, Oracle and/or its affiliates. All rights reserved.
 * Use is subject to license terms.
 *
 * Copyright (c) 2012, Intel Corporation.
 */
/*
 * This file is part of Lustre, http://www.lustre.org/
 * Lustre is a trademark of Sun Microsystems, Inc.
 */

#define DEBUG_SUBSYSTEM S_CLASS

#include <linux/seq_file.h>
#include <linux/statfs.h>
#include "../include/lprocfs_status.h"
#include "../include/obd_class.h"
#include "lmv_internal.h"

static ssize_t numobd_show(struct kobject *kobj, struct attribute *attr,
                           char *buf)
{
        struct obd_device *dev = container_of(kobj, struct obd_device,
                                              obd_kobj);
        struct lmv_desc *desc;

        desc = &dev->u.lmv.desc;
        return sprintf(buf, "%u\n", desc->ld_tgt_count);
}
LUSTRE_RO_ATTR(numobd);

static const char *placement_name[] = {
        [PLACEMENT_CHAR_POLICY] = "CHAR",
        [PLACEMENT_NID_POLICY]  = "NID",
        [PLACEMENT_INVAL_POLICY]  = "INVAL"
};

static enum placement_policy placement_name2policy(char *name, int len)
{
        int                  i;

        for (i = 0; i < PLACEMENT_MAX_POLICY; i++) {
                if (!strncmp(placement_name[i], name, len))
                        return i;
        }
        return PLACEMENT_INVAL_POLICY;
}

static const char *placement_policy2name(enum placement_policy placement)
{
        LASSERT(placement < PLACEMENT_MAX_POLICY);
        return placement_name[placement];
}

static ssize_t placement_show(struct kobject *kobj, struct attribute *attr,
                              char *buf)
{
        struct obd_device *dev = container_of(kobj, struct obd_device,
                                              obd_kobj);
        struct lmv_obd *lmv;

        lmv = &dev->u.lmv;
        return sprintf(buf, "%s\n", placement_policy2name(lmv->lmv_placement));
}

#define MAX_POLICY_STRING_SIZE 64

static ssize_t placement_store(struct kobject *kobj, struct attribute *attr,
                               const char *buffer,
                               size_t count)
{
        struct obd_device *dev = container_of(kobj, struct obd_device,
                                              obd_kobj);
        char dummy[MAX_POLICY_STRING_SIZE + 1];
        enum placement_policy policy;
        struct lmv_obd *lmv = &dev->u.lmv;

        memcpy(dummy, buffer, MAX_POLICY_STRING_SIZE);

        if (count > MAX_POLICY_STRING_SIZE)
                count = MAX_POLICY_STRING_SIZE;

        if (dummy[count - 1] == '\n')
                count--;
        dummy[count] = '\0';

        policy = placement_name2policy(dummy, count);
        if (policy != PLACEMENT_INVAL_POLICY) {
                spin_lock(&lmv->lmv_lock);
                lmv->lmv_placement = policy;
                spin_unlock(&lmv->lmv_lock);
        } else {
                return -EINVAL;
        }
        return count;
}
LUSTRE_RW_ATTR(placement);

static ssize_t activeobd_show(struct kobject *kobj, struct attribute *attr,
                              char *buf)
{
        struct obd_device *dev = container_of(kobj, struct obd_device,
                                              obd_kobj);
        struct lmv_desc *desc;

        desc = &dev->u.lmv.desc;
        return sprintf(buf, "%u\n", desc->ld_active_tgt_count);
}
LUSTRE_RO_ATTR(activeobd);

static int lmv_desc_uuid_seq_show(struct seq_file *m, void *v)
{
        struct obd_device *dev = (struct obd_device *)m->private;
        struct lmv_obd    *lmv;

        LASSERT(dev);
        lmv = &dev->u.lmv;
        seq_printf(m, "%s\n", lmv->desc.ld_uuid.uuid);
        return 0;
}

LPROC_SEQ_FOPS_RO(lmv_desc_uuid);

static void *lmv_tgt_seq_start(struct seq_file *p, loff_t *pos)
{
        struct obd_device       *dev = p->private;
        struct lmv_obd    *lmv = &dev->u.lmv;

        return (*pos >= lmv->desc.ld_tgt_count) ? NULL : lmv->tgts[*pos];
}

static void lmv_tgt_seq_stop(struct seq_file *p, void *v)
{
        return;
}

static void *lmv_tgt_seq_next(struct seq_file *p, void *v, loff_t *pos)
{
        struct obd_device       *dev = p->private;
        struct lmv_obd    *lmv = &dev->u.lmv;
        ++*pos;
        return (*pos >= lmv->desc.ld_tgt_count) ? NULL : lmv->tgts[*pos];
}

static int lmv_tgt_seq_show(struct seq_file *p, void *v)
{
        struct lmv_tgt_desc     *tgt = v;

        if (!tgt)
                return 0;
        seq_printf(p, "%d: %s %sACTIVE\n",
                   tgt->ltd_idx, tgt->ltd_uuid.uuid,
                   tgt->ltd_active ? "" : "IN");
        return 0;
}

static const struct seq_operations lmv_tgt_sops = {
        .start           = lmv_tgt_seq_start,
        .stop             = lmv_tgt_seq_stop,
        .next             = lmv_tgt_seq_next,
        .show             = lmv_tgt_seq_show,
};

static int lmv_target_seq_open(struct inode *inode, struct file *file)
{
        struct seq_file  *seq;
        int                  rc;

        rc = seq_open(file, &lmv_tgt_sops);
        if (rc)
                return rc;

        seq = file->private_data;
        seq->private = inode->i_private;

        return 0;
}

static struct lprocfs_vars lprocfs_lmv_obd_vars[] = {
        { "desc_uuid",    &lmv_desc_uuid_fops,    NULL, 0 },
        { NULL }
};

struct file_operations lmv_proc_target_fops = {
        .owner          = THIS_MODULE,
        .open            = lmv_target_seq_open,
        .read            = seq_read,
        .llseek        = seq_lseek,
        .release              = seq_release,
};

static struct attribute *lmv_attrs[] = {
        &lustre_attr_activeobd.attr,
        &lustre_attr_numobd.attr,
        &lustre_attr_placement.attr,
        NULL,
};

static struct attribute_group lmv_attr_group = {
        .attrs = lmv_attrs,
};

void lprocfs_lmv_init_vars(struct lprocfs_static_vars *lvars)
{
        lvars->sysfs_vars     = &lmv_attr_group;
        lvars->obd_vars       = lprocfs_lmv_obd_vars;
}