Merge tag 'powerpc-4.6-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc...

[deliverable/linux.git] / drivers / staging / lustre / lustre / include / obd.h

/*
 * 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) 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/obd.h"

#define IOC_OSC_TYPE     'h'
#define IOC_OSC_MIN_NR       20
#define IOC_OSC_SET_ACTIVE   _IOWR(IOC_OSC_TYPE, 21, struct obd_device *)
#define IOC_OSC_MAX_NR       50

#define IOC_MDC_TYPE     'i'
#define IOC_MDC_MIN_NR       20
#define IOC_MDC_MAX_NR       50

#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"

#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)
{
}

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 {
                /* Public members. */
                struct ost_id lw_object_oi; /* lov object id/seq */

                /* LOV-private members start here -- only for use in lov/. */
                __u32 lw_magic;
                __u32 lw_stripe_size;      /* size of the stripe */
                __u32 lw_pattern;         /* striping pattern (RAID0, RAID1) */
                __u16 lw_stripe_count;  /* number of objects being striped over */
                __u16 lw_layout_gen;       /* generation of the layout */
                char  lw_pool_name[LOV_MAXPOOLNAME]; /* pool name */
        } lsm_wire;

        struct lov_oinfo *lsm_oinfo[0];
};

#define lsm_oi           lsm_wire.lw_object_oi
#define lsm_magic       lsm_wire.lw_magic
#define lsm_layout_gen   lsm_wire.lw_layout_gen
#define lsm_stripe_size  lsm_wire.lw_stripe_size
#define lsm_pattern      lsm_wire.lw_pattern
#define lsm_stripe_count lsm_wire.lw_stripe_count
#define lsm_pool_name    lsm_wire.lw_pool_name

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;
};

void lov_stripe_lock(struct lov_stripe_md *md);
void lov_stripe_unlock(struct lov_stripe_md *md);

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;
        int count;
        u32 flag;
};

/* llog contexts */
enum llog_ctxt_id {
        LLOG_CONFIG_ORIG_CTXT  =  0,
        LLOG_CONFIG_REPL_CTXT,
        LLOG_MDS_OST_ORIG_CTXT,
        LLOG_MDS_OST_REPL_CTXT,
        LLOG_SIZE_ORIG_CTXT,
        LLOG_SIZE_REPL_CTXT,
        LLOG_RD1_ORIG_CTXT,
        LLOG_RD1_REPL_CTXT,
        LLOG_TEST_ORIG_CTXT,
        LLOG_TEST_REPL_CTXT,
        LLOG_LOVEA_ORIG_CTXT,
        LLOG_LOVEA_REPL_CTXT,
        LLOG_CHANGELOG_ORIG_CTXT,       /**< changelog generation on mdd */
        LLOG_CHANGELOG_REPL_CTXT,       /**< changelog access on clients */
        LLOG_CHANGELOG_USER_ORIG_CTXT,  /**< for multiple changelog consumers */
        LLOG_AGENT_ORIG_CTXT,           /**< agent requests generation on cdt */
        LLOG_MAX_CTXTS
};

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 OSC_MAX_RIF_DEFAULT       8
#define OSC_MAX_RIF_MAX  256
#define OSC_MAX_DIRTY_DEFAULT  (OSC_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
};

#define MDC_MAX_RIF_DEFAULT       8
#define MDC_MAX_RIF_MAX  512

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 */
        int                   cl_conn_count;
        /* max_mds_easize is purely a performance thing so we don't have to
         * call obd_size_diskmd() all the time.
         */
        int                      cl_default_mds_easize;
        int                      cl_max_mds_easize;
        int                      cl_default_mds_cookiesize;
        int                      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 */
        long                 cl_dirty;   /* all _dirty_ in bytes */
        long                 cl_dirty_max;     /* allowed w/o rpc */
        long                 cl_dirty_transit; /* dirty synchronous */
        long                 cl_avail_grant;   /* bytes of credit for ost */
        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;
        int               cl_chunk;
        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.)
         *
         * Exact type of ->cl_loi_list_lock is defined in arch/obd.h together
         * with client_obd_list_{un,}lock() and
         * client_obd_list_lock_{init,done}() functions.
         *
         * NB by Jinshan: though field names are still _loi_, but actually
         * osc_object{}s are in the list.
         */
        struct client_obd_lock         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;
        int                   cl_r_in_flight;
        int                   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;
        int                   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_t                *cl_lru_left;
        atomic_t                 cl_lru_busy;
        atomic_t                 cl_lru_shrinkers;
        atomic_t                 cl_lru_in_list;
        struct list_head         cl_lru_list; /* lru page list */
        struct client_obd_lock   cl_lru_list_lock; /* page list protector */

        /* 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 LUSTRE_VERSION_CODE >= OBD_OCD_VERSION(2, 7, 50, 0)
#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;
        /* 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 */
};

/* Round-robin allocator data */
struct lov_qos_rr {
        __u32          lqr_start_idx;   /* start index of new inode */
        __u32          lqr_offset_idx;  /* aliasing for start_idx  */
        int              lqr_start_count; /* reseed counter */
        struct ost_pool     lqr_pool;   /* round-robin optimized list */
        unsigned long       lqr_dirty:1;     /* recalc round-robin list */
};

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

struct lov_statfs_data {
        struct obd_info   lsd_oi;
        struct obd_statfs lsd_statfs;
};

/* Stripe placement optimization */
struct lov_qos {
        struct list_head    lq_oss_list; /* list of OSSs that targets use */
        struct rw_semaphore lq_rw_sem;
        __u32           lq_active_oss_count;
        unsigned int    lq_prio_free;   /* priority for free space */
        unsigned int    lq_threshold_rr;/* priority for rr */
        struct lov_qos_rr   lq_rr;        /* round robin qos data */
        unsigned long       lq_dirty:1,     /* recalc qos data */
                            lq_same_space:1,/* the ost's all have approx.
                                             * the same space avail
                                             */
                            lq_reset:1,     /* zero current penalties */
                            lq_statfs_in_progress:1; /* statfs op in
                                                        progress */
        /* qos statfs data */
        struct lov_statfs_data *lq_statfs_data;
        wait_queue_head_t lq_statfs_waitq; /* waitqueue to notify statfs
                                            * requests completion
                                            */
};

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 */
};

/* Pool metadata */
#define pool_tgt_size(_p)   _p->pool_obds.op_size
#define pool_tgt_count(_p)  _p->pool_obds.op_count
#define pool_tgt_array(_p)  _p->pool_obds.op_array
#define pool_tgt_rw_sem(_p) _p->pool_obds.op_rw_sem

struct pool_desc {
        char              pool_name[LOV_MAXPOOLNAME + 1]; /* name of pool */
        struct ost_pool       pool_obds;              /* pool members */
        atomic_t          pool_refcount;          /* pool ref. counter */
        struct lov_qos_rr     pool_rr;          /* round robin qos */
        struct hlist_node      pool_hash;             /* access by poolname */
        struct list_head            pool_list;        /* serial access */
        struct dentry           *pool_debugfs_entry;    /* file in debugfs */
        struct obd_device    *pool_lobd;        /* obd of the lov/lod to which
                                                 * this pool belongs
                                                 */
};

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_tgt_count;        /* how many OBD's */
        __u32              lov_active_tgt_count;  /* how many active */
        __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 pages from upper layer */
        void                   *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;
        int                     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            init_mutex;
        int                     connected;
        int                     max_easize;
        int                     max_def_easize;
        int                     max_cookiesize;
        int                     max_def_cookiesize;
        int                     server_timeout;

        int                     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           len;
        __u32           flags;
        struct page     *page;
        struct dentry   *dentry;
        int             lnb_grant_used;
        int             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_transno;
        __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;
        int                   oti_numcookies;
        /** synchronous write is needed */
        unsigned long            oti_sync_write:1;

        /* initial thread handling transaction */
        struct ptlrpc_thread *oti_thread;
        __u32               oti_conn_cnt;
        /** VBR: versions */
        __u64               oti_pre_version;
        /** JobID */
        char                *oti_jobid;

        struct obd_uuid  *oti_ost_uuid;
};

static inline void oti_alloc_cookies(struct obd_trans_info *oti,
                                     int num_cookies)
{
        if (!oti)
                return;

        if (num_cookies == 1)
                oti->oti_logcookies = &oti->oti_onecookie;
        else
                oti->oti_logcookies = libcfs_kvzalloc(num_cookies * sizeof(oti->oti_onecookie),
                                                      GFP_NOFS);

        oti->oti_numcookies = num_cookies;
}

static inline void oti_free_cookies(struct obd_trans_info *oti)
{
        if (!oti || !oti->oti_logcookies)
                return;

        if (oti->oti_logcookies == &oti->oti_onecookie)
                LASSERT(oti->oti_numcookies == 1);
        else
                kvfree(oti->oti_logcookies);

        oti->oti_logcookies = NULL;
        oti->oti_numcookies = 0;
}

/*
 * 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 {
        int             olg_seq;
        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
#define OBD_DEV_BY_DEVNAME      0xffffd0de

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_async_recov:1, /* allow asynchronous orphan cleanup */
                      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;
};

#define OBD_LLOG_FL_SENDNOW     0x0001
#define OBD_LLOG_FL_EXIT        0x0002

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_BLOCKSIZE_BITS      "blocksize_bits"
#define KEY_BLOCKSIZE      "blocksize"
#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_INIT_RECOV    "initial_recov"
#define KEY_INTERMDS        "inter_mds"
#define KEY_LAST_ID          "last_id"
#define KEY_LAST_FID            "last_fid"
#define KEY_LOCK_TO_STRIPE      "lock_to_stripe"
#define KEY_LOVDESC          "lovdesc"
#define KEY_LOV_IDX          "lov_idx"
#define KEY_MAX_EASIZE          "max_easize"
#define KEY_DEFAULT_EASIZE      "default_easize"
#define KEY_MDS_CONN        "mds_conn"
#define KEY_MGSSEC            "mgssec"
#define KEY_NEXT_ID          "next_id"
#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_CONNECT_FLAG        "connect_flags"
#define KEY_SYNC_LOCK_CANCEL    "sync_lock_cancel"

#define KEY_CACHE_SET           "cache_set"
#define KEY_CACHE_LRU_SHRINK    "cache_lru_shrink"
#define KEY_CHANGELOG_INDEX     "changelog_index"

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_READDIR | IT_GETATTR | IT_OPEN | IT_LOOKUP |
                              IT_LAYOUT))
                return LCK_CR;
        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;
}

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;
        int                  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;

        /* 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;

        /* Operation type */
        __u32              op_opc;

        /* Used by readdir */
        __u64              op_offset;

        /* Used by readdir */
        __u32              op_npages;

        /* used to transfer info between the stacks of MD client
         * see enum op_cli_flags
         */
        __u32                   op_cli_flags;

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

enum op_cli_flags {
        CLI_SET_MEA     = 1 << 0,
        CLI_RM_ENTRY    = 1 << 1,
};

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);
        __u64              mi_cbdata;
        unsigned int        mi_generation;
};

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 (*attach)(struct obd_device *dev, u32 len, void *data);
        int (*detach)(struct obd_device *dev);
        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)(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 (*preallocate)(struct lustre_handle *, u32 *req, u64 *ids);
        int (*create)(const struct lu_env *env, struct obd_export *exp,
                      struct obdo *oa, struct lov_stripe_md **ea,
                      struct obd_trans_info *oti);
        int (*destroy)(const struct lu_env *env, struct obd_export *exp,
                       struct obdo *oa, struct lov_stripe_md *ea,
                       struct obd_trans_info *oti, struct obd_export *md_exp);
        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 (*adjust_kms)(struct obd_export *exp, struct lov_stripe_md *lsm,
                          u64 size, int shrink);
        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 (*find_cbdata)(struct obd_export *, struct lov_stripe_md *,
                           ldlm_iterator_t it, void *data);
        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.
         */
};

enum {
        LUSTRE_OPC_MKDIR    = (1 << 0),
        LUSTRE_OPC_SYMLINK  = (1 << 1),
        LUSTRE_OPC_MKNOD    = (1 << 2),
        LUSTRE_OPC_CREATE   = (1 << 3),
        LUSTRE_OPC_ANY      = (1 << 4)
};

/* lmv structures */
#define MEA_MAGIC_LAST_CHAR      0xb2221ca1
#define MEA_MAGIC_ALL_CHARS      0xb222a11c
#define MEA_MAGIC_HASH_SEGMENT   0xb222a11b

#define MAX_HASH_SIZE_32         0x7fffffffUL
#define MAX_HASH_SIZE       0x7fffffffffffffffULL
#define MAX_HASH_HIGHEST_BIT     0x1000000000000000ULL

struct lustre_md {
        struct mdt_body  *body;
        struct lov_stripe_md    *lsm;
        struct lmv_stripe_md    *mea;
#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 lookup_intent;

struct md_ops {
        int (*getstatus)(struct obd_export *, struct lu_fid *);
        int (*null_inode)(struct obd_export *, const struct lu_fid *);
        int (*find_cbdata)(struct obd_export *, const struct lu_fid *,
                           ldlm_iterator_t, void *);
        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 *, int, int, __u32, __u32, 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 *,
                       struct lookup_intent *, struct md_op_data *,
                       struct lustre_handle *, void *, int,
                       struct ptlrpc_request **, __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 *,
                           void *, int, struct lookup_intent *, int,
                           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 *, int, const char *, int,
                      struct ptlrpc_request **);
        int (*is_subdir)(struct obd_export *, const struct lu_fid *,
                         const struct lu_fid *,
                           struct ptlrpc_request **);
        int (*setattr)(struct obd_export *, struct md_op_data *, void *,
                       int, void *, int, struct ptlrpc_request **,
                         struct md_open_data **mod);
        int (*sync)(struct obd_export *, const struct lu_fid *,
                    struct ptlrpc_request **);
        int (*readpage)(struct obd_export *, struct md_op_data *,
                        struct page **, struct ptlrpc_request **);

        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 *, int, int, int, int);

        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 (*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 *, __u64 *, 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_remote_perm)(struct obd_export *, const struct lu_fid *,
                               __u32, struct ptlrpc_request **);

        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 *);
        int (*lsm_destroy)(struct lov_stripe_md *, struct obdo *oa,
                           struct obd_export *md_exp);
        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;
        }
}

/* Requests for obd_extent_calc() */
#define OBD_CALC_STRIPE_START   1
#define OBD_CALC_STRIPE_END     2

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, int 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;
}

#endif /* __OBD_H */