/*
 * 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) 2007, 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.
 */

#ifndef __OBD_H
#define __OBD_H

#include <linux/spinlock.h>

#include "lustre/lustre_idl.h"
#include "lustre_lib.h"
#include "lu_ref.h"
#include "lustre_export.h"
#include "lustre_fid.h"
#include "lustre_fld.h"
#include "lustre_handles.h"
#include "lustre_intent.h"

#define MAX_OBD_DEVICES 8192

struct osc_async_rc {
	int     ar_rc;
	int     ar_force_sync;
	__u64   ar_min_xid;
};

struct lov_oinfo {		 /* per-stripe data structure */
	struct ost_id   loi_oi;    /* object ID/Sequence on the target OST */
	int loi_ost_idx;	   /* OST stripe index in lov_tgt_desc->tgts */
	int loi_ost_gen;	   /* generation of this loi_ost_idx */

	unsigned long loi_kms_valid:1;
	__u64 loi_kms;	     /* known minimum size */
	struct ost_lvb loi_lvb;
	struct osc_async_rc     loi_ar;
};

static inline void loi_kms_set(struct lov_oinfo *oinfo, __u64 kms)
{
	oinfo->loi_kms = kms;
	oinfo->loi_kms_valid = 1;
}

static inline void loi_init(struct lov_oinfo *loi)
{
}

/*
 * If we are unable to get the maximum object size from the OST in
 * ocd_maxbytes using OBD_CONNECT_MAXBYTES, then we fall back to using
 * the old maximum object size from ext3.
 */
#define LUSTRE_EXT3_STRIPE_MAXBYTES 0x1fffffff000ULL

struct lov_stripe_md {
	atomic_t     lsm_refc;
	spinlock_t	lsm_lock;
	pid_t	    lsm_lock_owner; /* debugging */

	/* maximum possible file size, might change as OSTs status changes,
	 * e.g. disconnected, deactivated
	 */
	__u64		lsm_maxbytes;
	struct ost_id	lsm_oi;
	__u32		lsm_magic;
	__u32		lsm_stripe_size;
	__u32		lsm_pattern;	/* striping pattern (RAID0, RAID1) */
	__u16		lsm_stripe_count;
	__u16		lsm_layout_gen;
	char		lsm_pool_name[LOV_MAXPOOLNAME + 1];
	struct lov_oinfo *lsm_oinfo[0];
};

static inline bool lsm_is_released(struct lov_stripe_md *lsm)
{
	return !!(lsm->lsm_pattern & LOV_PATTERN_F_RELEASED);
}

static inline bool lsm_has_objects(struct lov_stripe_md *lsm)
{
	if (!lsm)
		return false;
	if (lsm_is_released(lsm))
		return false;
	return true;
}

static inline int lov_stripe_md_size(unsigned int stripe_count)
{
	struct lov_stripe_md lsm;

	return sizeof(lsm) + stripe_count * sizeof(lsm.lsm_oinfo[0]);
}

struct obd_info;

typedef int (*obd_enqueue_update_f)(void *cookie, int rc);

/* obd info for a particular level (lov, osc). */
struct obd_info {
	/* Flags used for set request specific flags:
	   - while lock handling, the flags obtained on the enqueue
	   request are set here.
	   - while stats, the flags used for control delay/resend.
	   - while setattr, the flags used for distinguish punch operation
	 */
	__u64		   oi_flags;
	/* lsm data specific for every OSC. */
	struct lov_stripe_md   *oi_md;
	/* obdo data specific for every OSC, if needed at all. */
	struct obdo	    *oi_oa;
	/* statfs data specific for every OSC, if needed at all. */
	struct obd_statfs      *oi_osfs;
	/* An update callback which is called to update some data on upper
	 * level. E.g. it is used for update lsm->lsm_oinfo at every received
	 * request in osc level for enqueue requests. It is also possible to
	 * update some caller data from LOV layer if needed.
	 */
	obd_enqueue_update_f    oi_cb_up;
};

struct obd_type {
	struct list_head typ_chain;
	struct obd_ops *typ_dt_ops;
	struct md_ops *typ_md_ops;
	struct dentry *typ_debugfs_entry;
	char *typ_name;
	int  typ_refcnt;
	struct lu_device_type *typ_lu;
	spinlock_t obd_type_lock;
	struct kobject *typ_kobj;
};

struct brw_page {
	u64 off;
	struct page *pg;
	unsigned int count;
	u32 flag;
};

struct timeout_item {
	enum timeout_event ti_event;
	unsigned long	 ti_timeout;
	timeout_cb_t       ti_cb;
	void	      *ti_cb_data;
	struct list_head	 ti_obd_list;
	struct list_head	 ti_chain;
};

#define OBD_MAX_RIF_DEFAULT	8
#define OBD_MAX_RIF_MAX		512
#define OSC_MAX_RIF_MAX		256
#define OSC_MAX_DIRTY_DEFAULT	(OBD_MAX_RIF_DEFAULT * 4)
#define OSC_MAX_DIRTY_MB_MAX	2048	/* arbitrary, but < MAX_LONG bytes */
#define OSC_DEFAULT_RESENDS	10

/* possible values for fo_sync_lock_cancel */
enum {
	NEVER_SYNC_ON_CANCEL = 0,
	BLOCKING_SYNC_ON_CANCEL = 1,
	ALWAYS_SYNC_ON_CANCEL = 2,
	NUM_SYNC_ON_CANCEL_STATES
};

enum obd_cl_sem_lock_class {
	OBD_CLI_SEM_NORMAL,
	OBD_CLI_SEM_MGC,
	OBD_CLI_SEM_MDCOSC,
};

/*
 * Limit reply buffer size for striping data to one x86_64 page. This
 * value is chosen to fit the striping data for common use cases while
 * staying well below the limit at which the buffer must be backed by
 * vmalloc(). Excessive use of vmalloc() may cause spinlock contention
 * on the MDS.
 */
#define OBD_MAX_DEFAULT_EA_SIZE		4096
#define OBD_MAX_DEFAULT_COOKIE_SIZE	4096

struct mdc_rpc_lock;
struct obd_import;
struct client_obd {
	struct rw_semaphore  cl_sem;
	struct obd_uuid	  cl_target_uuid;
	struct obd_import       *cl_import; /* ptlrpc connection state */
	size_t			 cl_conn_count;
	/*
	 * Cache maximum and default values for easize and cookiesize. This is
	 * strictly a performance optimization to minimize calls to
	 * obd_size_diskmd(). The default values are used to calculate the
	 * initial size of a request buffer. The ptlrpc layer will resize the
	 * buffer as needed to accommodate a larger reply from the
	 * server. The default values should be small enough to avoid wasted
	 * memory and excessive use of vmalloc(), yet large enough to avoid
	 * reallocating the buffer in the common use case.
	 */
	/*
	 * Default EA size for striping attributes. It is initialized at
	 * mount-time based on the default stripe width of the filesystem,
	 * then it tracks the largest observed EA size advertised by
	 * the MDT, up to a maximum value of OBD_MAX_DEFAULT_EA_SIZE.
	 */
	u32			 cl_default_mds_easize;
	/* Maximum possible EA size computed at mount-time based on
	 * the number of OSTs in the filesystem. May be increased at
	 * run-time if a larger observed size is advertised by the MDT.
	 */
	u32			 cl_max_mds_easize;
	/* Default cookie size for llog cookies (see struct llog_cookie). It is
	 * initialized to zero at mount-time, then it tracks the largest
	 * observed cookie size advertised by the MDT, up to a maximum value of
	 * OBD_MAX_DEFAULT_COOKIE_SIZE. Note that llog_cookies are not
	 * used by clients communicating with MDS versions 2.4.0 and later.
	 */
	u32			 cl_default_mds_cookiesize;
	/* Maximum possible cookie size computed at mount-time based on
	 * the number of OSTs in the filesystem. May be increased at
	 * run-time if a larger observed size is advertised by the MDT.
	 */
	u32			 cl_max_mds_cookiesize;

	enum lustre_sec_part     cl_sp_me;
	enum lustre_sec_part     cl_sp_to;
	struct sptlrpc_flavor    cl_flvr_mgc;   /* fixed flavor of mgc->mgs */

	/* the grant values are protected by loi_list_lock below */
	unsigned long		 cl_dirty_pages;	/* all _dirty_ in pahges */
	unsigned long		 cl_dirty_max_pages;	/* allowed w/o rpc */
	unsigned long		 cl_dirty_transit;	/* dirty synchronous */
	unsigned long		 cl_avail_grant;	/* bytes of credit for ost */
	unsigned long		 cl_lost_grant;		/* lost credits (trunc) */

	/* since we allocate grant by blocks, we don't know how many grant will
	 * be used to add a page into cache. As a solution, we reserve maximum
	 * grant before trying to dirty a page and unreserve the rest.
	 * See osc_{reserve|unreserve}_grant for details.
	 */
	long		 cl_reserved_grant;
	struct list_head cl_cache_waiters; /* waiting for cache/grant */
	unsigned long	 cl_next_shrink_grant;   /* jiffies */
	struct list_head cl_grant_shrink_list;  /* Timeout event list */
	int		 cl_grant_shrink_interval; /* seconds */

	/* A chunk is an optimal size used by osc_extent to determine
	 * the extent size. A chunk is max(PAGE_SIZE, OST block size)
	 */
	int		  cl_chunkbits;
	unsigned int	  cl_extent_tax; /* extent overhead, by bytes */

	/* keep track of objects that have lois that contain pages which
	 * have been queued for async brw.  this lock also protects the
	 * lists of osc_client_pages that hang off of the loi
	 */
	/*
	 * ->cl_loi_list_lock protects consistency of
	 * ->cl_loi_{ready,read,write}_list. ->ap_make_ready() and
	 * ->ap_completion() call-backs are executed under this lock. As we
	 * cannot guarantee that these call-backs never block on all platforms
	 * (as a matter of fact they do block on Mac OS X), type of
	 * ->cl_loi_list_lock is platform dependent: it's a spin-lock on Linux
	 * and blocking mutex on Mac OS X. (Alternative is to make this lock
	 * blocking everywhere, but we don't want to slow down fast-path of
	 * our main platform.)
	 *
	 * NB by Jinshan: though field names are still _loi_, but actually
	 * osc_object{}s are in the list.
	 */
	spinlock_t		       cl_loi_list_lock;
	struct list_head	       cl_loi_ready_list;
	struct list_head	       cl_loi_hp_ready_list;
	struct list_head	       cl_loi_write_list;
	struct list_head	       cl_loi_read_list;
	__u32			 cl_r_in_flight;
	__u32			 cl_w_in_flight;
	/* just a sum of the loi/lop pending numbers to be exported by sysfs */
	atomic_t	     cl_pending_w_pages;
	atomic_t	     cl_pending_r_pages;
	__u32			 cl_max_pages_per_rpc;
	__u32			 cl_max_rpcs_in_flight;
	struct obd_histogram     cl_read_rpc_hist;
	struct obd_histogram     cl_write_rpc_hist;
	struct obd_histogram     cl_read_page_hist;
	struct obd_histogram     cl_write_page_hist;
	struct obd_histogram     cl_read_offset_hist;
	struct obd_histogram     cl_write_offset_hist;

	/* lru for osc caching pages */
	struct cl_client_cache	*cl_cache;
	struct list_head	 cl_lru_osc; /* member of cl_cache->ccc_lru */
	atomic_long_t		*cl_lru_left;
	atomic_long_t		 cl_lru_busy;
	atomic_long_t		 cl_lru_in_list;
	atomic_t		 cl_lru_shrinkers;
	struct list_head	 cl_lru_list; /* lru page list */
	spinlock_t		 cl_lru_list_lock; /* page list protector */
	atomic_long_t		 cl_unstable_count;

	/* number of in flight destroy rpcs is limited to max_rpcs_in_flight */
	atomic_t	     cl_destroy_in_flight;
	wait_queue_head_t	      cl_destroy_waitq;

	struct mdc_rpc_lock     *cl_rpc_lock;
	struct mdc_rpc_lock     *cl_close_lock;

	/* mgc datastruct */
	atomic_t	     cl_mgc_refcount;
	struct obd_export       *cl_mgc_mgsexp;

	/* checksumming for data sent over the network */
	unsigned int	     cl_checksum:1; /* 0 = disabled, 1 = enabled */
	/* supported checksum types that are worked out at connect time */
	__u32		    cl_supp_cksum_types;
	/* checksum algorithm to be used */
	enum cksum_type	     cl_cksum_type;

	/* also protected by the poorly named _loi_list_lock lock above */
	struct osc_async_rc      cl_ar;

	/* used by quotacheck when the servers are older than 2.4 */
	int		      cl_qchk_stat; /* quotacheck stat of the peer */
#define CL_NOT_QUOTACHECKED 1   /* client->cl_qchk_stat init value */
#if OBD_OCD_VERSION(2, 7, 53, 0) < LUSTRE_VERSION_CODE
#warning "please consider removing quotacheck compatibility code"
#endif

	/* sequence manager */
	struct lu_client_seq    *cl_seq;

	atomic_t	     cl_resends; /* resend count */

	/* ptlrpc work for writeback in ptlrpcd context */
	void		    *cl_writeback_work;
	void			*cl_lru_work;
	/* hash tables for osc_quota_info */
	struct cfs_hash	      *cl_quota_hash[MAXQUOTAS];
};

#define obd2cli_tgt(obd) ((char *)(obd)->u.cli.cl_target_uuid.uuid)

struct obd_id_info {
	__u32   idx;
	u64	*data;
};

struct echo_client_obd {
	struct obd_export	*ec_exp;   /* the local connection to osc/lov */
	spinlock_t		ec_lock;
	struct list_head	   ec_objects;
	struct list_head	   ec_locks;
	__u64		ec_unique;
};

/* Generic subset of OSTs */
struct ost_pool {
	__u32	      *op_array;      /* array of index of lov_obd->lov_tgts */
	unsigned int	op_count;      /* number of OSTs in the array */
	unsigned int	op_size;       /* allocated size of lp_array */
	struct rw_semaphore op_rw_sem;     /* to protect ost_pool use */
};

/* allow statfs data caching for 1 second */
#define OBD_STATFS_CACHE_SECONDS 1

struct lov_tgt_desc {
	struct list_head	  ltd_kill;
	struct obd_uuid     ltd_uuid;
	struct obd_device  *ltd_obd;
	struct obd_export  *ltd_exp;
	__u32	       ltd_gen;
	__u32	       ltd_index;   /* index in lov_obd->tgts */
	unsigned long       ltd_active:1,/* is this target up for requests */
			    ltd_activate:1,/* should  target be activated */
			    ltd_reap:1;  /* should this target be deleted */
};

struct lov_obd {
	struct lov_desc	 desc;
	struct lov_tgt_desc   **lov_tgts;	      /* sparse array */
	struct ost_pool	 lov_packed;	    /* all OSTs in a packed array */
	struct mutex		lov_lock;
	struct obd_connect_data lov_ocd;
	atomic_t	    lov_refcount;
	__u32		   lov_death_row;/* tgts scheduled to be deleted */
	__u32		   lov_tgt_size;   /* size of tgts array */
	int		     lov_connects;
	int		     lov_pool_count;
	struct cfs_hash	     *lov_pools_hash_body; /* used for key access */
	struct list_head	lov_pool_list; /* used for sequential access */
	struct dentry		*lov_pool_debugfs_entry;
	enum lustre_sec_part    lov_sp_me;

	/* Cached LRU and unstable data from upper layer */
	struct cl_client_cache *lov_cache;

	struct rw_semaphore     lov_notify_lock;

	struct kobject		*lov_tgts_kobj;
};

struct lmv_tgt_desc {
	struct obd_uuid		ltd_uuid;
	struct obd_export	*ltd_exp;
	u32			ltd_idx;
	struct mutex		ltd_fid_mutex;
	unsigned long		ltd_active:1; /* target up for requests */
};

enum placement_policy {
	PLACEMENT_CHAR_POLICY   = 0,
	PLACEMENT_NID_POLICY    = 1,
	PLACEMENT_INVAL_POLICY  = 2,
	PLACEMENT_MAX_POLICY
};

struct lmv_obd {
	int			refcount;
	struct lu_client_fld	lmv_fld;
	spinlock_t		lmv_lock;
	enum placement_policy	lmv_placement;
	struct lmv_desc		desc;
	struct obd_uuid		cluuid;
	struct obd_export	*exp;

	struct mutex		lmv_init_mutex;
	int			connected;
	int			max_easize;
	int			max_def_easize;
	int			max_cookiesize;
	int			max_def_cookiesize;

	u32			tgts_size; /* size of tgts array */
	struct lmv_tgt_desc	**tgts;

	struct obd_connect_data	conn_data;
	struct kobject		*lmv_tgts_kobj;
};

struct niobuf_local {
	__u64		lnb_file_offset;
	__u32		lnb_page_offset;
	__u32		lnb_len;
	__u32		lnb_flags;
	struct page	*lnb_page;
	void		*lnb_data;
	int		lnb_rc;
};

#define LUSTRE_FLD_NAME	 "fld"
#define LUSTRE_SEQ_NAME	 "seq"

#define LUSTRE_MDD_NAME	 "mdd"
#define LUSTRE_OSD_LDISKFS_NAME	"osd-ldiskfs"
#define LUSTRE_OSD_ZFS_NAME     "osd-zfs"
#define LUSTRE_VVP_NAME	 "vvp"
#define LUSTRE_LMV_NAME	 "lmv"
#define LUSTRE_SLP_NAME	 "slp"
#define LUSTRE_LOD_NAME		"lod"
#define LUSTRE_OSP_NAME		"osp"
#define LUSTRE_LWP_NAME		"lwp"

/* obd device type names */
 /* FIXME all the references to LUSTRE_MDS_NAME should be swapped with LUSTRE_MDT_NAME */
#define LUSTRE_MDS_NAME	 "mds"
#define LUSTRE_MDT_NAME	 "mdt"
#define LUSTRE_MDC_NAME	 "mdc"
#define LUSTRE_OSS_NAME	 "ost"       /* FIXME change name to oss */
#define LUSTRE_OST_NAME	 "obdfilter" /* FIXME change name to ost */
#define LUSTRE_OSC_NAME	 "osc"
#define LUSTRE_LOV_NAME	 "lov"
#define LUSTRE_MGS_NAME	 "mgs"
#define LUSTRE_MGC_NAME	 "mgc"

#define LUSTRE_ECHO_NAME	"obdecho"
#define LUSTRE_ECHO_CLIENT_NAME "echo_client"
#define LUSTRE_QMT_NAME	 "qmt"

/* Constant obd names (post-rename) */
#define LUSTRE_MDS_OBDNAME "MDS"
#define LUSTRE_OSS_OBDNAME "OSS"
#define LUSTRE_MGS_OBDNAME "MGS"
#define LUSTRE_MGC_OBDNAME "MGC"

/* Don't conflict with on-wire flags OBD_BRW_WRITE, etc */
#define N_LOCAL_TEMP_PAGE 0x10000000

struct obd_trans_info {
	__u64		    oti_xid;
	/* Only used on the server side for tracking acks. */
	struct oti_req_ack_lock {
		struct lustre_handle lock;
		__u32		mode;
	}			oti_ack_locks[4];
	void		    *oti_handle;
	struct llog_cookie       oti_onecookie;
	struct llog_cookie      *oti_logcookies;

	/** VBR: versions */
	__u64		    oti_pre_version;
};

/*
 * Events signalled through obd_notify() upcall-chain.
 */
enum obd_notify_event {
	/* target added */
	OBD_NOTIFY_CREATE,
	/* Device connect start */
	OBD_NOTIFY_CONNECT,
	/* Device activated */
	OBD_NOTIFY_ACTIVE,
	/* Device deactivated */
	OBD_NOTIFY_INACTIVE,
	/* Device disconnected */
	OBD_NOTIFY_DISCON,
	/* Connect data for import were changed */
	OBD_NOTIFY_OCD,
	/* Sync request */
	OBD_NOTIFY_SYNC_NONBLOCK,
	OBD_NOTIFY_SYNC,
	/* Configuration event */
	OBD_NOTIFY_CONFIG,
	/* Administratively deactivate/activate event */
	OBD_NOTIFY_DEACTIVATE,
	OBD_NOTIFY_ACTIVATE
};

/*
 * Data structure used to pass obd_notify()-event to non-obd listeners (llite
 * being main example).
 */
struct obd_notify_upcall {
	int (*onu_upcall)(struct obd_device *host, struct obd_device *watched,
			  enum obd_notify_event ev, void *owner, void *data);
	/* Opaque datum supplied by upper layer listener */
	void *onu_owner;
};

struct target_recovery_data {
	svc_handler_t		trd_recovery_handler;
	pid_t			trd_processing_task;
	struct completion	trd_starting;
	struct completion	trd_finishing;
};

struct obd_llog_group {
	struct llog_ctxt  *olg_ctxts[LLOG_MAX_CTXTS];
	wait_queue_head_t	olg_waitq;
	spinlock_t	   olg_lock;
	struct mutex	   olg_cat_processing;
};

/* corresponds to one of the obd's */
#define OBD_DEVICE_MAGIC	0XAB5CD6EF

struct lvfs_run_ctxt {
	struct dt_device *dt;
};

struct obd_device {
	struct obd_type	*obd_type;
	__u32		   obd_magic;

	/* common and UUID name of this device */
	char		    obd_name[MAX_OBD_NAME];
	struct obd_uuid	 obd_uuid;

	struct lu_device       *obd_lu_dev;

	int		     obd_minor;
	/* bitfield modification is protected by obd_dev_lock */
	unsigned long obd_attached:1,      /* finished attach */
		      obd_set_up:1,	/* finished setup */
		      obd_version_recov:1, /* obd uses version checking */
		      obd_replayable:1,/* recovery is enabled; inform clients */
		      obd_no_transno:1,  /* no committed-transno notification */
		      obd_no_recov:1,      /* fail instead of retry messages */
		      obd_stopping:1,      /* started cleanup */
		      obd_starting:1,      /* started setup */
		      obd_force:1,	 /* cleanup with > 0 obd refcount */
		      obd_fail:1,	 /* cleanup with failover */
		      obd_no_conn:1,       /* deny new connections */
		      obd_inactive:1,      /* device active/inactive
					    * (for sysfs status only!!)
					    */
		      obd_no_ir:1,	 /* no imperative recovery. */
		      obd_process_conf:1;  /* device is processing mgs config */
	/* use separate field as it is set in interrupt to don't mess with
	 * protection of other bits using _bh lock
	 */
	unsigned long obd_recovery_expired:1;
	/* uuid-export hash body */
	struct cfs_hash	     *obd_uuid_hash;
	atomic_t	    obd_refcount;
	wait_queue_head_t	     obd_refcount_waitq;
	struct list_head	      obd_exports;
	struct list_head	      obd_unlinked_exports;
	struct list_head	      obd_delayed_exports;
	int		     obd_num_exports;
	spinlock_t		obd_nid_lock;
	struct ldlm_namespace  *obd_namespace;
	struct ptlrpc_client	obd_ldlm_client; /* XXX OST/MDS only */
	/* a spinlock is OK for what we do now, may need a semaphore later */
	spinlock_t		obd_dev_lock; /* protect OBD bitfield above */
	struct mutex		obd_dev_mutex;
	__u64			obd_last_committed;
	spinlock_t		obd_osfs_lock;
	struct obd_statfs	obd_osfs;       /* locked by obd_osfs_lock */
	__u64			obd_osfs_age;
	struct lvfs_run_ctxt	obd_lvfs_ctxt;
	struct obd_llog_group	obd_olg;	/* default llog group */
	struct obd_device	*obd_observer;
	struct rw_semaphore	obd_observer_link_sem;
	struct obd_notify_upcall obd_upcall;
	struct obd_export       *obd_self_export;

	union {
		struct client_obd cli;
		struct echo_client_obd echo_client;
		struct lov_obd lov;
		struct lmv_obd lmv;
	} u;
	/* Fields used by LProcFS */
	unsigned int	   obd_cntr_base;
	struct lprocfs_stats  *obd_stats;

	unsigned int	   md_cntr_base;
	struct lprocfs_stats  *md_stats;

	struct dentry		*obd_debugfs_entry;
	struct dentry		*obd_svc_debugfs_entry;
	struct lprocfs_stats  *obd_svc_stats;
	atomic_t	   obd_evict_inprogress;
	wait_queue_head_t	    obd_evict_inprogress_waitq;
	struct list_head	obd_evict_list; /* protected with pet_lock */

	/**
	 * Ldlm pool part. Save last calculated SLV and Limit.
	 */
	rwlock_t		obd_pool_lock;
	int		    obd_pool_limit;
	__u64		  obd_pool_slv;

	/**
	 * A list of outstanding class_incref()'s against this obd. For
	 * debugging.
	 */
	struct lu_ref	  obd_reference;

	int		       obd_conn_inprogress;

	struct kobject		obd_kobj; /* sysfs object */
	struct completion	obd_kobj_unregister;
};

enum obd_cleanup_stage {
/* Special case hack for MDS LOVs */
	OBD_CLEANUP_EARLY,
/* can be directly mapped to .ldto_device_fini() */
	OBD_CLEANUP_EXPORTS,
};

/* get/set_info keys */
#define KEY_ASYNC	       "async"
#define KEY_CHANGELOG_CLEAR     "changelog_clear"
#define KEY_FID2PATH	    "fid2path"
#define KEY_CHECKSUM	    "checksum"
#define KEY_CLEAR_FS	    "clear_fs"
#define KEY_CONN_DATA	   "conn_data"
#define KEY_EVICT_BY_NID	"evict_by_nid"
#define KEY_FIEMAP	      "fiemap"
#define KEY_FLUSH_CTX	   "flush_ctx"
#define KEY_GRANT_SHRINK	"grant_shrink"
#define KEY_HSM_COPYTOOL_SEND   "hsm_send"
#define KEY_INIT_RECOV_BACKUP   "init_recov_bk"
#define KEY_INTERMDS	    "inter_mds"
#define KEY_LAST_ID	     "last_id"
#define KEY_LAST_FID		"last_fid"
#define KEY_LOVDESC	     "lovdesc"
#define KEY_MAX_EASIZE		"max_easize"
#define KEY_DEFAULT_EASIZE	"default_easize"
#define KEY_MGSSEC	      "mgssec"
#define KEY_READ_ONLY	   "read-only"
#define KEY_REGISTER_TARGET     "register_target"
#define KEY_SET_FS	      "set_fs"
#define KEY_TGT_COUNT	   "tgt_count"
/*      KEY_SET_INFO in lustre_idl.h */
#define KEY_SPTLRPC_CONF	"sptlrpc_conf"

#define KEY_CACHE_SET		"cache_set"
#define KEY_CACHE_LRU_SHRINK	"cache_lru_shrink"

struct lu_context;

/* /!\ must be coherent with include/linux/namei.h on patched kernel */
#define IT_OPEN     (1 << 0)
#define IT_CREAT    (1 << 1)
#define IT_READDIR  (1 << 2)
#define IT_GETATTR  (1 << 3)
#define IT_LOOKUP   (1 << 4)
#define IT_UNLINK   (1 << 5)
#define IT_TRUNC    (1 << 6)
#define IT_GETXATTR (1 << 7)
#define IT_EXEC     (1 << 8)
#define IT_PIN      (1 << 9)
#define IT_LAYOUT   (1 << 10)
#define IT_QUOTA_DQACQ (1 << 11)
#define IT_QUOTA_CONN  (1 << 12)
#define IT_SETXATTR (1 << 13)

static inline int it_to_lock_mode(struct lookup_intent *it)
{
	/* CREAT needs to be tested before open (both could be set) */
	if (it->it_op & IT_CREAT)
		return LCK_CW;
	else if (it->it_op & (IT_GETATTR | IT_OPEN | IT_LOOKUP |
			      IT_LAYOUT))
		return LCK_CR;
	else if (it->it_op & IT_READDIR)
		return LCK_PR;
	else if (it->it_op &  IT_GETXATTR)
		return LCK_PR;
	else if (it->it_op &  IT_SETXATTR)
		return LCK_PW;

	LASSERTF(0, "Invalid it_op: %d\n", it->it_op);
	return -EINVAL;
}

enum md_cli_flags {
	CLI_SET_MEA	= BIT(0),
	CLI_RM_ENTRY	= BIT(1),
	CLI_HASH64	= BIT(2),
	CLI_API32	= BIT(3),
	CLI_MIGRATE	= BIT(4),
};

struct md_op_data {
	struct lu_fid	   op_fid1; /* operation fid1 (usually parent) */
	struct lu_fid	   op_fid2; /* operation fid2 (usually child) */
	struct lu_fid	   op_fid3; /* 2 extra fids to find conflicting */
	struct lu_fid	   op_fid4; /* to the operation locks. */
	u32			op_mds;  /* what mds server open will go to */
	struct lustre_handle    op_handle;
	s64			op_mod_time;
	const char	     *op_name;
	size_t			op_namelen;
	__u32		   op_mode;
	struct lmv_stripe_md   *op_mea1;
	struct lmv_stripe_md   *op_mea2;
	__u32		   op_suppgids[2];
	__u32		   op_fsuid;
	__u32		   op_fsgid;
	cfs_cap_t	       op_cap;
	void		   *op_data;
	size_t			op_data_size;

	/* iattr fields and blocks. */
	struct iattr	    op_attr;
	unsigned int	    op_attr_flags;
	__u64		   op_valid;
	loff_t		  op_attr_blocks;

	/* Size-on-MDS epoch and flags. */
	__u64		   op_ioepoch;
	__u32		   op_flags;

	/* Various operation flags. */
	enum mds_op_bias        op_bias;

	/* Used by readdir */
	__u64		   op_offset;

	/* Used by readdir */
	__u32			op_max_pages;

	/* used to transfer info between the stacks of MD client
	 * see enum op_cli_flags
	 */
	enum md_cli_flags	op_cli_flags;

	/* File object data version for HSM release, on client */
	__u64			op_data_version;
	struct lustre_handle	op_lease_handle;

	/* default stripe offset */
	__u32			op_default_stripe_offset;
};

struct md_callback {
	int (*md_blocking_ast)(struct ldlm_lock *lock,
			       struct ldlm_lock_desc *desc,
			       void *data, int flag);
};

struct md_enqueue_info;
/* metadata stat-ahead */

struct md_enqueue_info {
	struct md_op_data       mi_data;
	struct lookup_intent    mi_it;
	struct lustre_handle    mi_lockh;
	struct inode	   *mi_dir;
	int (*mi_cb)(struct ptlrpc_request *req,
		     struct md_enqueue_info *minfo, int rc);
	void			*mi_cbdata;
};

struct obd_ops {
	struct module *owner;
	int (*iocontrol)(unsigned int cmd, struct obd_export *exp, int len,
			 void *karg, void __user *uarg);
	int (*get_info)(const struct lu_env *env, struct obd_export *,
			__u32 keylen, void *key, __u32 *vallen, void *val,
			struct lov_stripe_md *lsm);
	int (*set_info_async)(const struct lu_env *, struct obd_export *,
			      __u32 keylen, void *key,
			      __u32 vallen, void *val,
			      struct ptlrpc_request_set *set);
	int (*setup)(struct obd_device *dev, struct lustre_cfg *cfg);
	int (*precleanup)(struct obd_device *dev,
			  enum obd_cleanup_stage cleanup_stage);
	int (*cleanup)(struct obd_device *dev);
	int (*process_config)(struct obd_device *dev, u32 len, void *data);
	int (*postrecov)(struct obd_device *dev);
	int (*add_conn)(struct obd_import *imp, struct obd_uuid *uuid,
			int priority);
	int (*del_conn)(struct obd_import *imp, struct obd_uuid *uuid);
	/* connect to the target device with given connection
	 * data. @ocd->ocd_connect_flags is modified to reflect flags actually
	 * granted by the target, which are guaranteed to be a subset of flags
	 * asked for. If @ocd == NULL, use default parameters.
	 */
	int (*connect)(const struct lu_env *env,
		       struct obd_export **exp, struct obd_device *src,
		       struct obd_uuid *cluuid, struct obd_connect_data *ocd,
		       void *localdata);
	int (*reconnect)(const struct lu_env *env,
			 struct obd_export *exp, struct obd_device *src,
			 struct obd_uuid *cluuid,
			 struct obd_connect_data *ocd,
			 void *localdata);
	int (*disconnect)(struct obd_export *exp);

	/* Initialize/finalize fids infrastructure. */
	int (*fid_init)(struct obd_device *obd,
			struct obd_export *exp, enum lu_cli_type type);
	int (*fid_fini)(struct obd_device *obd);

	/* Allocate new fid according to passed @hint. */
	int (*fid_alloc)(const struct lu_env *env, struct obd_export *exp,
			 struct lu_fid *fid, struct md_op_data *op_data);

	/*
	 * Object with @fid is getting deleted, we may want to do something
	 * about this.
	 */
	int (*statfs)(const struct lu_env *, struct obd_export *exp,
		      struct obd_statfs *osfs, __u64 max_age, __u32 flags);
	int (*statfs_async)(struct obd_export *exp, struct obd_info *oinfo,
			    __u64 max_age, struct ptlrpc_request_set *set);
	int (*packmd)(struct obd_export *exp, struct lov_mds_md **disk_tgt,
		      struct lov_stripe_md *mem_src);
	int (*unpackmd)(struct obd_export *exp,
			struct lov_stripe_md **mem_tgt,
			struct lov_mds_md *disk_src, int disk_len);
	int (*create)(const struct lu_env *env, struct obd_export *exp,
		      struct obdo *oa, struct obd_trans_info *oti);
	int (*destroy)(const struct lu_env *env, struct obd_export *exp,
		       struct obdo *oa, struct obd_trans_info *oti);
	int (*setattr)(const struct lu_env *, struct obd_export *exp,
		       struct obd_info *oinfo, struct obd_trans_info *oti);
	int (*setattr_async)(struct obd_export *exp, struct obd_info *oinfo,
			     struct obd_trans_info *oti,
			     struct ptlrpc_request_set *rqset);
	int (*getattr)(const struct lu_env *env, struct obd_export *exp,
		       struct obd_info *oinfo);
	int (*getattr_async)(struct obd_export *exp, struct obd_info *oinfo,
			     struct ptlrpc_request_set *set);
	int (*preprw)(const struct lu_env *env, int cmd,
		      struct obd_export *exp, struct obdo *oa, int objcount,
		      struct obd_ioobj *obj, struct niobuf_remote *remote,
		      int *nr_pages, struct niobuf_local *local,
		      struct obd_trans_info *oti);
	int (*commitrw)(const struct lu_env *env, int cmd,
			struct obd_export *exp, struct obdo *oa,
			int objcount, struct obd_ioobj *obj,
			struct niobuf_remote *remote, int pages,
			struct niobuf_local *local,
			struct obd_trans_info *oti, int rc);
	int (*init_export)(struct obd_export *exp);
	int (*destroy_export)(struct obd_export *exp);

	/* metadata-only methods */
	int (*import_event)(struct obd_device *, struct obd_import *,
			    enum obd_import_event);

	int (*notify)(struct obd_device *obd, struct obd_device *watched,
		      enum obd_notify_event ev, void *data);

	int (*health_check)(const struct lu_env *env, struct obd_device *);
	struct obd_uuid *(*get_uuid)(struct obd_export *exp);

	/* quota methods */
	int (*quotacheck)(struct obd_device *, struct obd_export *,
			  struct obd_quotactl *);
	int (*quotactl)(struct obd_device *, struct obd_export *,
			struct obd_quotactl *);

	/* pools methods */
	int (*pool_new)(struct obd_device *obd, char *poolname);
	int (*pool_del)(struct obd_device *obd, char *poolname);
	int (*pool_add)(struct obd_device *obd, char *poolname,
			char *ostname);
	int (*pool_rem)(struct obd_device *obd, char *poolname,
			char *ostname);
	void (*getref)(struct obd_device *obd);
	void (*putref)(struct obd_device *obd);
	/*
	 * NOTE: If adding ops, add another LPROCFS_OBD_OP_INIT() line
	 * to lprocfs_alloc_obd_stats() in obdclass/lprocfs_status.c.
	 * Also, add a wrapper function in include/linux/obd_class.h.
	 */
};

/* lmv structures */
struct lustre_md {
	struct mdt_body	 *body;
	struct lov_stripe_md    *lsm;
	struct lmv_stripe_md    *lmv;
#ifdef CONFIG_FS_POSIX_ACL
	struct posix_acl	*posix_acl;
#endif
	struct mdt_remote_perm  *remote_perm;
};

struct md_open_data {
	struct obd_client_handle *mod_och;
	struct ptlrpc_request    *mod_open_req;
	struct ptlrpc_request    *mod_close_req;
	atomic_t		  mod_refcount;
	bool			  mod_is_create;
};

struct obd_client_handle {
	struct lustre_handle	 och_fh;
	struct lu_fid		 och_fid;
	struct md_open_data	*och_mod;
	struct lustre_handle	 och_lease_handle; /* open lock for lease */
	__u32			 och_magic;
	int			 och_flags;
};

#define OBD_CLIENT_HANDLE_MAGIC 0xd15ea5ed

struct lookup_intent;
struct cl_attr;

struct md_ops {
	int (*getstatus)(struct obd_export *, struct lu_fid *);
	int (*null_inode)(struct obd_export *, const struct lu_fid *);
	int (*close)(struct obd_export *, struct md_op_data *,
		     struct md_open_data *, struct ptlrpc_request **);
	int (*create)(struct obd_export *, struct md_op_data *,
		      const void *, size_t, umode_t, uid_t, gid_t,
		      cfs_cap_t, __u64, struct ptlrpc_request **);
	int (*done_writing)(struct obd_export *, struct md_op_data  *,
			    struct md_open_data *);
	int (*enqueue)(struct obd_export *, struct ldlm_enqueue_info *,
		       const ldlm_policy_data_t *,
		       struct lookup_intent *, struct md_op_data *,
		       struct lustre_handle *, __u64);
	int (*getattr)(struct obd_export *, struct md_op_data *,
		       struct ptlrpc_request **);
	int (*getattr_name)(struct obd_export *, struct md_op_data *,
			    struct ptlrpc_request **);
	int (*intent_lock)(struct obd_export *, struct md_op_data *,
			   struct lookup_intent *,
			   struct ptlrpc_request **,
			   ldlm_blocking_callback, __u64);
	int (*link)(struct obd_export *, struct md_op_data *,
		    struct ptlrpc_request **);
	int (*rename)(struct obd_export *, struct md_op_data *,
		      const char *, size_t, const char *, size_t,
		      struct ptlrpc_request **);
	int (*setattr)(struct obd_export *, struct md_op_data *, void *,
		       size_t, void *, size_t, struct ptlrpc_request **,
			 struct md_open_data **mod);
	int (*sync)(struct obd_export *, const struct lu_fid *,
		    struct ptlrpc_request **);
	int (*read_page)(struct obd_export *, struct md_op_data *,
			 struct md_callback *cb_op, __u64 hash_offset,
			 struct page **ppage);
	int (*unlink)(struct obd_export *, struct md_op_data *,
		      struct ptlrpc_request **);

	int (*setxattr)(struct obd_export *, const struct lu_fid *,
			u64, const char *, const char *, int, int, int, __u32,
			struct ptlrpc_request **);

	int (*getxattr)(struct obd_export *, const struct lu_fid *,
			u64, const char *, const char *, int, int, int,
			struct ptlrpc_request **);

	int (*init_ea_size)(struct obd_export *, u32, u32, u32, u32);

	int (*get_lustre_md)(struct obd_export *, struct ptlrpc_request *,
			     struct obd_export *, struct obd_export *,
			     struct lustre_md *);

	int (*free_lustre_md)(struct obd_export *, struct lustre_md *);

	int (*merge_attr)(struct obd_export *,
			  const struct lmv_stripe_md *lsm,
			  struct cl_attr *attr, ldlm_blocking_callback);

	int (*set_open_replay_data)(struct obd_export *,
				    struct obd_client_handle *,
				    struct lookup_intent *);
	int (*clear_open_replay_data)(struct obd_export *,
				      struct obd_client_handle *);
	int (*set_lock_data)(struct obd_export *, const struct lustre_handle *,
			     void *, __u64 *);

	enum ldlm_mode (*lock_match)(struct obd_export *, __u64,
				     const struct lu_fid *, enum ldlm_type,
				     ldlm_policy_data_t *, enum ldlm_mode,
				     struct lustre_handle *);

	int (*cancel_unused)(struct obd_export *, const struct lu_fid *,
			     ldlm_policy_data_t *, enum ldlm_mode,
			     enum ldlm_cancel_flags flags, void *opaque);

	int (*get_fid_from_lsm)(struct obd_export *,
				const struct lmv_stripe_md *,
				const char *name, int namelen,
				struct lu_fid *fid);

	int (*intent_getattr_async)(struct obd_export *,
				    struct md_enqueue_info *,
				    struct ldlm_enqueue_info *);

	int (*revalidate_lock)(struct obd_export *, struct lookup_intent *,
			       struct lu_fid *, __u64 *bits);

	/*
	 * NOTE: If adding ops, add another LPROCFS_MD_OP_INIT() line to
	 * lprocfs_alloc_md_stats() in obdclass/lprocfs_status.c. Also, add a
	 * wrapper function in include/linux/obd_class.h.
	 */
};

struct lsm_operations {
	void (*lsm_free)(struct lov_stripe_md *);
	void (*lsm_stripe_by_index)(struct lov_stripe_md *, int *, u64 *,
				    u64 *);
	void (*lsm_stripe_by_offset)(struct lov_stripe_md *, int *, u64 *,
				     u64 *);
	int (*lsm_lmm_verify)(struct lov_mds_md *lmm, int lmm_bytes,
			      __u16 *stripe_count);
	int (*lsm_unpackmd)(struct lov_obd *lov, struct lov_stripe_md *lsm,
			    struct lov_mds_md *lmm);
};

extern const struct lsm_operations lsm_v1_ops;
extern const struct lsm_operations lsm_v3_ops;
static inline const struct lsm_operations *lsm_op_find(int magic)
{
	switch (magic) {
	case LOV_MAGIC_V1:
	       return &lsm_v1_ops;
	case LOV_MAGIC_V3:
	       return &lsm_v3_ops;
	default:
	       CERROR("Cannot recognize lsm_magic %08x\n", magic);
	       return NULL;
	}
}

static inline struct md_open_data *obd_mod_alloc(void)
{
	struct md_open_data *mod;

	mod = kzalloc(sizeof(*mod), GFP_NOFS);
	if (!mod)
		return NULL;
	atomic_set(&mod->mod_refcount, 1);
	return mod;
}

#define obd_mod_get(mod) atomic_inc(&(mod)->mod_refcount)
#define obd_mod_put(mod)					\
({							      \
	if (atomic_dec_and_test(&(mod)->mod_refcount)) {	  \
		if ((mod)->mod_open_req)			  \
			ptlrpc_req_finished((mod)->mod_open_req);   \
		kfree(mod);			      \
	}						       \
})

void obdo_from_inode(struct obdo *dst, struct inode *src, u32 valid);
void obdo_set_parent_fid(struct obdo *dst, const struct lu_fid *parent);

/* return 1 if client should be resend request */
static inline int client_should_resend(int resend, struct client_obd *cli)
{
	return atomic_read(&cli->cl_resends) ?
	       atomic_read(&cli->cl_resends) > resend : 1;
}

/**
 * Return device name for this device
 *
 * XXX: lu_device is declared before obd_device, while a pointer pointing
 * back to obd_device in lu_device, so this helper function defines here
 * instead of in lu_object.h
 */
static inline const char *lu_dev_name(const struct lu_device *lu_dev)
{
	return lu_dev->ld_obd->obd_name;
}

static inline bool filename_is_volatile(const char *name, size_t namelen,
					int *idx)
{
	const char	*start;
	char		*end;

	if (strncmp(name, LUSTRE_VOLATILE_HDR, LUSTRE_VOLATILE_HDR_LEN) != 0)
		return false;

	/* caller does not care of idx */
	if (!idx)
		return true;

	/* volatile file, the MDT can be set from name */
	/* name format is LUSTRE_VOLATILE_HDR:[idx]: */
	/* if no MDT is specified, use std way */
	if (namelen < LUSTRE_VOLATILE_HDR_LEN + 2)
		goto bad_format;
	/* test for no MDT idx case */
	if ((*(name + LUSTRE_VOLATILE_HDR_LEN) == ':') &&
	    (*(name + LUSTRE_VOLATILE_HDR_LEN + 1) == ':')) {
		*idx = -1;
		return true;
	}
	/* we have an idx, read it */
	start = name + LUSTRE_VOLATILE_HDR_LEN + 1;
	*idx = simple_strtoul(start, &end, 0);
	/* error cases:
	 * no digit, no trailing :, negative value
	 */
	if (((*idx == 0) && (end == start)) ||
	    (*end != ':') || (*idx < 0))
		goto bad_format;

	return true;
bad_format:
	/* bad format of mdt idx, we cannot return an error
	 * to caller so we use hash algo
	 */
	CERROR("Bad volatile file name format: %s\n",
	       name + LUSTRE_VOLATILE_HDR_LEN);
	return false;
}

static inline int cli_brw_size(struct obd_device *obd)
{
	return obd->u.cli.cl_max_pages_per_rpc << PAGE_SHIFT;
}

/*
 * when RPC size or the max RPCs in flight is increased, the max dirty pages
 * of the client should be increased accordingly to avoid sending fragmented
 * RPCs over the network when the client runs out of the maximum dirty space
 * when so many RPCs are being generated.
 */
static inline void client_adjust_max_dirty(struct client_obd *cli)
{
	/* initializing */
	if (cli->cl_dirty_max_pages <= 0)
		cli->cl_dirty_max_pages =
			(OSC_MAX_DIRTY_DEFAULT * 1024 * 1024) >> PAGE_SHIFT;
	else {
		unsigned long dirty_max = cli->cl_max_rpcs_in_flight *
					  cli->cl_max_pages_per_rpc;

		if (dirty_max > cli->cl_dirty_max_pages)
			cli->cl_dirty_max_pages = dirty_max;
	}

	if (cli->cl_dirty_max_pages > totalram_pages / 8)
		cli->cl_dirty_max_pages = totalram_pages / 8;
}

#endif /* __OBD_H */