/*
 * 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.gnu.org/licenses/gpl-2.0.html
 *
 * GPL HEADER END
 */
/*
 * Copyright (c) 1999, 2010, Oracle and/or its affiliates. All rights reserved.
 * Use is subject to license terms.
 *
 * Copyright (c) 2011, 2015, 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/atomic.h>

#include <obd_support.h>
#include <obd_class.h>
#include <uapi/linux/lnet/lnetctl.h>
#include <lustre_debug.h>
#include <lprocfs_status.h>
#include <linux/list.h>
#include <cl_object.h>
#include <uapi/linux/lustre/lustre_ioctl.h>
#include "llog_internal.h"

struct obd_device *obd_devs[MAX_OBD_DEVICES];
struct list_head obd_types;
DEFINE_RWLOCK(obd_dev_lock);

/* The following are visible and mutable through /sys/fs/lustre. */
unsigned int obd_debug_peer_on_timeout;
EXPORT_SYMBOL(obd_debug_peer_on_timeout);
unsigned int obd_dump_on_timeout;
EXPORT_SYMBOL(obd_dump_on_timeout);
unsigned int obd_dump_on_eviction;
EXPORT_SYMBOL(obd_dump_on_eviction);
unsigned long obd_max_dirty_pages;
EXPORT_SYMBOL(obd_max_dirty_pages);
atomic_long_t obd_dirty_pages;
EXPORT_SYMBOL(obd_dirty_pages);
unsigned int obd_timeout = OBD_TIMEOUT_DEFAULT;   /* seconds */
EXPORT_SYMBOL(obd_timeout);
unsigned int obd_timeout_set;
EXPORT_SYMBOL(obd_timeout_set);
/* Adaptive timeout defs here instead of ptlrpc module for /sys/fs/ access */
unsigned int at_min;
EXPORT_SYMBOL(at_min);
unsigned int at_max = 600;
EXPORT_SYMBOL(at_max);
unsigned int at_history = 600;
EXPORT_SYMBOL(at_history);
int at_early_margin = 5;
EXPORT_SYMBOL(at_early_margin);
int at_extra = 30;
EXPORT_SYMBOL(at_extra);

atomic_long_t obd_dirty_transit_pages;
EXPORT_SYMBOL(obd_dirty_transit_pages);

char obd_jobid_var[JOBSTATS_JOBID_VAR_MAX_LEN + 1] = JOBSTATS_DISABLE;
char obd_jobid_node[LUSTRE_JOBID_SIZE + 1];

/* Get jobid of current process from stored variable or calculate
 * it from pid and user_id.
 *
 * Historically this was also done by reading the environment variable
 * stored in between the "env_start" & "env_end" of task struct.
 * This is now deprecated.
 */
int lustre_get_jobid(char *jobid)
{
	memset(jobid, 0, LUSTRE_JOBID_SIZE);
	/* Jobstats isn't enabled */
	if (strcmp(obd_jobid_var, JOBSTATS_DISABLE) == 0)
		return 0;

	/* Use process name + fsuid as jobid */
	if (strcmp(obd_jobid_var, JOBSTATS_PROCNAME_UID) == 0) {
		snprintf(jobid, LUSTRE_JOBID_SIZE, "%s.%u",
			 current_comm(),
			 from_kuid(&init_user_ns, current_fsuid()));
		return 0;
	}

	/* Whole node dedicated to single job */
	if (strcmp(obd_jobid_var, JOBSTATS_NODELOCAL) == 0) {
		strcpy(jobid, obd_jobid_node);
		return 0;
	}

	return -ENOENT;
}
EXPORT_SYMBOL(lustre_get_jobid);

static int class_resolve_dev_name(__u32 len, const char *name)
{
	int rc;
	int dev;

	if (!len || !name) {
		CERROR("No name passed,!\n");
		rc = -EINVAL;
		goto out;
	}
	if (name[len - 1] != 0) {
		CERROR("Name not nul terminated!\n");
		rc = -EINVAL;
		goto out;
	}

	CDEBUG(D_IOCTL, "device name %s\n", name);
	dev = class_name2dev(name);
	if (dev == -1) {
		CDEBUG(D_IOCTL, "No device for name %s!\n", name);
		rc = -EINVAL;
		goto out;
	}

	CDEBUG(D_IOCTL, "device name %s, dev %d\n", name, dev);
	rc = dev;

out:
	return rc;
}

int class_handle_ioctl(unsigned int cmd, unsigned long arg)
{
	char *buf = NULL;
	struct obd_ioctl_data *data;
	struct libcfs_debug_ioctl_data *debug_data;
	struct obd_device *obd = NULL;
	int err = 0, len = 0;

	/* only for debugging */
	if (cmd == LIBCFS_IOC_DEBUG_MASK) {
		debug_data = (struct libcfs_debug_ioctl_data *)arg;
		libcfs_subsystem_debug = debug_data->subs;
		libcfs_debug = debug_data->debug;
		return 0;
	}

	CDEBUG(D_IOCTL, "cmd = %x\n", cmd);
	if (obd_ioctl_getdata(&buf, &len, (void __user *)arg)) {
		CERROR("OBD ioctl: data error\n");
		return -EINVAL;
	}
	data = (struct obd_ioctl_data *)buf;

	switch (cmd) {
	case OBD_IOC_PROCESS_CFG: {
		struct lustre_cfg *lcfg;

		if (!data->ioc_plen1 || !data->ioc_pbuf1) {
			CERROR("No config buffer passed!\n");
			err = -EINVAL;
			goto out;
		}
		lcfg = kzalloc(data->ioc_plen1, GFP_NOFS);
		if (!lcfg) {
			err = -ENOMEM;
			goto out;
		}
		if (copy_from_user(lcfg, data->ioc_pbuf1, data->ioc_plen1))
			err = -EFAULT;
		if (!err)
			err = lustre_cfg_sanity_check(lcfg, data->ioc_plen1);
		if (!err)
			err = class_process_config(lcfg);

		kfree(lcfg);
		goto out;
	}

	case OBD_GET_VERSION:
		if (!data->ioc_inlbuf1) {
			CERROR("No buffer passed in ioctl\n");
			err = -EINVAL;
			goto out;
		}

		if (strlen(LUSTRE_VERSION_STRING) + 1 > data->ioc_inllen1) {
			CERROR("ioctl buffer too small to hold version\n");
			err = -EINVAL;
			goto out;
		}

		memcpy(data->ioc_bulk, LUSTRE_VERSION_STRING,
		       strlen(LUSTRE_VERSION_STRING) + 1);

		if (copy_to_user((void __user *)arg, data, len))
			err = -EFAULT;
		goto out;

	case OBD_IOC_NAME2DEV: {
		/* Resolve a device name.  This does not change the
		 * currently selected device.
		 */
		int dev;

		dev = class_resolve_dev_name(data->ioc_inllen1,
					     data->ioc_inlbuf1);
		data->ioc_dev = dev;
		if (dev < 0) {
			err = -EINVAL;
			goto out;
		}

		if (copy_to_user((void __user *)arg, data, sizeof(*data)))
			err = -EFAULT;
		goto out;
	}

	case OBD_IOC_UUID2DEV: {
		/* Resolve a device uuid.  This does not change the
		 * currently selected device.
		 */
		int dev;
		struct obd_uuid uuid;

		if (!data->ioc_inllen1 || !data->ioc_inlbuf1) {
			CERROR("No UUID passed!\n");
			err = -EINVAL;
			goto out;
		}
		if (data->ioc_inlbuf1[data->ioc_inllen1 - 1] != 0) {
			CERROR("UUID not NUL terminated!\n");
			err = -EINVAL;
			goto out;
		}

		CDEBUG(D_IOCTL, "device name %s\n", data->ioc_inlbuf1);
		obd_str2uuid(&uuid, data->ioc_inlbuf1);
		dev = class_uuid2dev(&uuid);
		data->ioc_dev = dev;
		if (dev == -1) {
			CDEBUG(D_IOCTL, "No device for UUID %s!\n",
			       data->ioc_inlbuf1);
			err = -EINVAL;
			goto out;
		}

		CDEBUG(D_IOCTL, "device name %s, dev %d\n", data->ioc_inlbuf1,
		       dev);

		if (copy_to_user((void __user *)arg, data, sizeof(*data)))
			err = -EFAULT;
		goto out;
	}

	case OBD_IOC_GETDEVICE: {
		int     index = data->ioc_count;
		char    *status, *str;

		if (!data->ioc_inlbuf1) {
			CERROR("No buffer passed in ioctl\n");
			err = -EINVAL;
			goto out;
		}
		if (data->ioc_inllen1 < 128) {
			CERROR("ioctl buffer too small to hold version\n");
			err = -EINVAL;
			goto out;
		}

		obd = class_num2obd(index);
		if (!obd) {
			err = -ENOENT;
			goto out;
		}

		if (obd->obd_stopping)
			status = "ST";
		else if (obd->obd_set_up)
			status = "UP";
		else if (obd->obd_attached)
			status = "AT";
		else
			status = "--";
		str = (char *)data->ioc_bulk;
		snprintf(str, len - sizeof(*data), "%3d %s %s %s %s %d",
			 (int)index, status, obd->obd_type->typ_name,
			 obd->obd_name, obd->obd_uuid.uuid,
			 atomic_read(&obd->obd_refcount));

		if (copy_to_user((void __user *)arg, data, len))
			err = -EFAULT;
		goto out;
	}
	}

	if (data->ioc_dev == OBD_DEV_BY_DEVNAME) {
		if (data->ioc_inllen4 <= 0 || !data->ioc_inlbuf4) {
			err = -EINVAL;
			goto out;
		}
		if (strnlen(data->ioc_inlbuf4, MAX_OBD_NAME) >= MAX_OBD_NAME) {
			err = -EINVAL;
			goto out;
		}
		obd = class_name2obd(data->ioc_inlbuf4);
	} else if (data->ioc_dev < class_devno_max()) {
		obd = class_num2obd(data->ioc_dev);
	} else {
		CERROR("OBD ioctl: No device\n");
		err = -EINVAL;
		goto out;
	}

	if (!obd) {
		CERROR("OBD ioctl : No Device %d\n", data->ioc_dev);
		err = -EINVAL;
		goto out;
	}
	LASSERT(obd->obd_magic == OBD_DEVICE_MAGIC);

	if (!obd->obd_set_up || obd->obd_stopping) {
		CERROR("OBD ioctl: device not setup %d\n", data->ioc_dev);
		err = -EINVAL;
		goto out;
	}

	switch (cmd) {
	case OBD_IOC_NO_TRANSNO: {
		if (!obd->obd_attached) {
			CERROR("Device %d not attached\n", obd->obd_minor);
			err = -ENODEV;
			goto out;
		}
		CDEBUG(D_HA, "%s: disabling committed-transno notification\n",
		       obd->obd_name);
		obd->obd_no_transno = 1;
		err = 0;
		goto out;
	}

	default: {
		err = obd_iocontrol(cmd, obd->obd_self_export, len, data, NULL);
		if (err)
			goto out;

		if (copy_to_user((void __user *)arg, data, len))
			err = -EFAULT;
		goto out;
	}
	}

 out:
	kvfree(buf);
	return err;
} /* class_handle_ioctl */

#define OBD_INIT_CHECK
static int obd_init_checks(void)
{
	__u64 u64val, div64val;
	char buf[64];
	int len, ret = 0;

	CDEBUG(D_INFO, "LPU64=%s, LPD64=%s, LPX64=%s\n", "%llu", "%lld", "%#llx");

	CDEBUG(D_INFO, "OBD_OBJECT_EOF = %#llx\n", (__u64)OBD_OBJECT_EOF);

	u64val = OBD_OBJECT_EOF;
	CDEBUG(D_INFO, "u64val OBD_OBJECT_EOF = %#llx\n", u64val);
	if (u64val != OBD_OBJECT_EOF) {
		CERROR("__u64 %#llx(%d) != 0xffffffffffffffff\n",
		       u64val, (int)sizeof(u64val));
		ret = -EINVAL;
	}
	len = snprintf(buf, sizeof(buf), "%#llx", u64val);
	if (len != 18) {
		CWARN("LPX64 wrong length! strlen(%s)=%d != 18\n", buf, len);
		ret = -EINVAL;
	}

	div64val = OBD_OBJECT_EOF;
	CDEBUG(D_INFO, "u64val OBD_OBJECT_EOF = %#llx\n", u64val);
	if (u64val != OBD_OBJECT_EOF) {
		CERROR("__u64 %#llx(%d) != 0xffffffffffffffff\n",
		       u64val, (int)sizeof(u64val));
		ret = -EOVERFLOW;
	}
	if (u64val >> 8 != OBD_OBJECT_EOF >> 8) {
		CERROR("__u64 %#llx(%d) != 0xffffffffffffffff\n",
		       u64val, (int)sizeof(u64val));
		return -EOVERFLOW;
	}
	if (do_div(div64val, 256) != (u64val & 255)) {
		CERROR("do_div(%#llx,256) != %llu\n", u64val, u64val & 255);
		return -EOVERFLOW;
	}
	if (u64val >> 8 != div64val) {
		CERROR("do_div(%#llx,256) %llu != %llu\n",
		       u64val, div64val, u64val >> 8);
		return -EOVERFLOW;
	}
	len = snprintf(buf, sizeof(buf), "%#llx", u64val);
	if (len != 18) {
		CWARN("LPX64 wrong length! strlen(%s)=%d != 18\n", buf, len);
		ret = -EINVAL;
	}
	len = snprintf(buf, sizeof(buf), "%llu", u64val);
	if (len != 20) {
		CWARN("LPU64 wrong length! strlen(%s)=%d != 20\n", buf, len);
		ret = -EINVAL;
	}
	len = snprintf(buf, sizeof(buf), "%lld", u64val);
	if (len != 2) {
		CWARN("LPD64 wrong length! strlen(%s)=%d != 2\n", buf, len);
		ret = -EINVAL;
	}
	if ((u64val & ~PAGE_MASK) >= PAGE_SIZE) {
		CWARN("mask failed: u64val %llu >= %llu\n", u64val,
		      (__u64)PAGE_SIZE);
		ret = -EINVAL;
	}

	return ret;
}

static int __init obdclass_init(void)
{
	int i, err;

	LCONSOLE_INFO("Lustre: Build Version: " LUSTRE_VERSION_STRING "\n");

	spin_lock_init(&obd_types_lock);
	obd_zombie_impexp_init();

	err = obd_init_checks();
	if (err)
		return err;

	class_init_uuidlist();
	err = class_handle_init();
	if (err)
		return err;

	INIT_LIST_HEAD(&obd_types);

	err = misc_register(&obd_psdev);
	if (err) {
		CERROR("cannot register %d err %d\n", OBD_DEV_MINOR, err);
		return err;
	}

	/* This struct is already zeroed for us (static global) */
	for (i = 0; i < class_devno_max(); i++)
		obd_devs[i] = NULL;

	/* Default the dirty page cache cap to 1/2 of system memory.
	 * For clients with less memory, a larger fraction is needed
	 * for other purposes (mostly for BGL).
	 */
	if (totalram_pages <= 512 << (20 - PAGE_SHIFT))
		obd_max_dirty_pages = totalram_pages / 4;
	else
		obd_max_dirty_pages = totalram_pages / 2;

	err = obd_init_caches();
	if (err)
		return err;

	err = class_procfs_init();
	if (err)
		return err;

	err = obd_sysctl_init();
	if (err)
		return err;

	err = lu_global_init();
	if (err)
		return err;

	err = cl_global_init();
	if (err != 0)
		return err;

	err = llog_info_init();
	if (err)
		return err;

	err = lustre_register_fs();

	return err;
}

static void obdclass_exit(void)
{
	lustre_unregister_fs();

	misc_deregister(&obd_psdev);
	llog_info_fini();
	cl_global_fini();
	lu_global_fini();

	obd_cleanup_caches();

	class_procfs_clean();

	class_handle_cleanup();
	class_exit_uuidlist();
	obd_zombie_impexp_stop();
}

MODULE_AUTHOR("OpenSFS, Inc. <http://www.lustre.org/>");
MODULE_DESCRIPTION("Lustre Class Driver");
MODULE_VERSION(LUSTRE_VERSION_STRING);
MODULE_LICENSE("GPL");

module_init(obdclass_init);
module_exit(obdclass_exit);