Subversion Repositories test_project

/*

 * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.

 * Copyright (C) 2004-2006 Red Hat, Inc.  All rights reserved.

 *

 * This copyrighted material is made available to anyone wishing to use,

 * modify, copy, or redistribute it subject to the terms and conditions

 * of the GNU General Public License version 2.

 */

#ifndef __LM_INTERFACE_DOT_H__

#define __LM_INTERFACE_DOT_H__

typedef void (*lm_callback_t) (void *ptr, unsigned int type, void *data);

/*

 * lm_mount() flags

 *

 * LM_MFLAG_SPECTATOR

 * GFS is asking to join the filesystem's lockspace, but it doesn't want to

 * modify the filesystem.  The lock module shouldn't assign a journal to the FS

 * mount.  It shouldn't send recovery callbacks to the FS mount.  If the node

 * dies or withdraws, all locks can be wiped immediately.

 */

#define LM_MFLAG_SPECTATOR      0x00000001

/*

 * lm_lockstruct flags

 *

 * LM_LSFLAG_LOCAL

 * The lock_nolock module returns LM_LSFLAG_LOCAL to GFS, indicating that GFS

 * can make single-node optimizations.

 */

#define LM_LSFLAG_LOCAL         0x00000001

/*

 * lm_lockname types

 */

#define LM_TYPE_RESERVED        0x00

#define LM_TYPE_NONDISK         0x01

#define LM_TYPE_INODE           0x02

#define LM_TYPE_RGRP            0x03

#define LM_TYPE_META            0x04

#define LM_TYPE_IOPEN           0x05

#define LM_TYPE_FLOCK           0x06

#define LM_TYPE_PLOCK           0x07

#define LM_TYPE_QUOTA           0x08

#define LM_TYPE_JOURNAL         0x09

/*

 * lm_lock() states

 *

 * SHARED is compatible with SHARED, not with DEFERRED or EX.

 * DEFERRED is compatible with DEFERRED, not with SHARED or EX.

 */

#define LM_ST_UNLOCKED          0

#define LM_ST_EXCLUSIVE         1

#define LM_ST_DEFERRED          2

#define LM_ST_SHARED            3

/*

 * lm_lock() flags

 *

 * LM_FLAG_TRY

 * Don't wait to acquire the lock if it can't be granted immediately.

 *

 * LM_FLAG_TRY_1CB

 * Send one blocking callback if TRY is set and the lock is not granted.

 *

 * LM_FLAG_NOEXP

 * GFS sets this flag on lock requests it makes while doing journal recovery.

 * These special requests should not be blocked due to the recovery like

 * ordinary locks would be.

 *

 * LM_FLAG_ANY

 * A SHARED request may also be granted in DEFERRED, or a DEFERRED request may

 * also be granted in SHARED.  The preferred state is whichever is compatible

 * with other granted locks, or the specified state if no other locks exist.

 *

 * LM_FLAG_PRIORITY

 * Override fairness considerations.  Suppose a lock is held in a shared state

 * and there is a pending request for the deferred state.  A shared lock

 * request with the priority flag would be allowed to bypass the deferred

 * request and directly join the other shared lock.  A shared lock request

 * without the priority flag might be forced to wait until the deferred

 * requested had acquired and released the lock.

 */

#define LM_FLAG_TRY             0x00000001

#define LM_FLAG_TRY_1CB         0x00000002

#define LM_FLAG_NOEXP           0x00000004

#define LM_FLAG_ANY             0x00000008

#define LM_FLAG_PRIORITY        0x00000010

/*

 * lm_lock() and lm_async_cb return flags

 *

 * LM_OUT_ST_MASK

 * Masks the lower two bits of lock state in the returned value.

 *

 * LM_OUT_CACHEABLE

 * The lock hasn't been released so GFS can continue to cache data for it.

 *

 * LM_OUT_CANCELED

 * The lock request was canceled.

 *

 * LM_OUT_ASYNC

 * The result of the request will be returned in an LM_CB_ASYNC callback.

 */

#define LM_OUT_ST_MASK          0x00000003

#define LM_OUT_CACHEABLE        0x00000004

#define LM_OUT_CANCELED         0x00000008

#define LM_OUT_ASYNC            0x00000080

#define LM_OUT_ERROR            0x00000100

/*

 * lm_callback_t types

 *

 * LM_CB_NEED_E LM_CB_NEED_D LM_CB_NEED_S

 * Blocking callback, a remote node is requesting the given lock in

 * EXCLUSIVE, DEFERRED, or SHARED.

 *

 * LM_CB_NEED_RECOVERY

 * The given journal needs to be recovered.

 *

 * LM_CB_DROPLOCKS

 * Reduce the number of cached locks.

 *

 * LM_CB_ASYNC

 * The given lock has been granted.

 */

#define LM_CB_NEED_E            257

#define LM_CB_NEED_D            258

#define LM_CB_NEED_S            259

#define LM_CB_NEED_RECOVERY     260

#define LM_CB_DROPLOCKS         261

#define LM_CB_ASYNC             262

/*

 * lm_recovery_done() messages

 */

#define LM_RD_GAVEUP            308

#define LM_RD_SUCCESS           309

struct lm_lockname {

        u64 ln_number;

        unsigned int ln_type;

};

#define lm_name_equal(name1, name2) \

        (((name1)->ln_number == (name2)->ln_number) && \

         ((name1)->ln_type == (name2)->ln_type)) \

struct lm_async_cb {

        struct lm_lockname lc_name;

        int lc_ret;

};

struct lm_lockstruct;

struct lm_lockops {

        const char *lm_proto_name;

        /*

         * Mount/Unmount

         */

        int (*lm_mount) (char *table_name, char *host_data,

                         lm_callback_t cb, void *cb_data,

                         unsigned int min_lvb_size, int flags,

                         struct lm_lockstruct *lockstruct,

                         struct kobject *fskobj);

        void (*lm_others_may_mount) (void *lockspace);

        void (*lm_unmount) (void *lockspace);

        void (*lm_withdraw) (void *lockspace);

        /*

         * Lock oriented operations

         */

        int (*lm_get_lock) (void *lockspace, struct lm_lockname *name, void **lockp);

        void (*lm_put_lock) (void *lock);

        unsigned int (*lm_lock) (void *lock, unsigned int cur_state,

                                 unsigned int req_state, unsigned int flags);

        unsigned int (*lm_unlock) (void *lock, unsigned int cur_state);

        void (*lm_cancel) (void *lock);

        int (*lm_hold_lvb) (void *lock, char **lvbp);

        void (*lm_unhold_lvb) (void *lock, char *lvb);

        /*

         * Posix Lock oriented operations

         */

        int (*lm_plock_get) (void *lockspace, struct lm_lockname *name,

                             struct file *file, struct file_lock *fl);

        int (*lm_plock) (void *lockspace, struct lm_lockname *name,

                         struct file *file, int cmd, struct file_lock *fl);

        int (*lm_punlock) (void *lockspace, struct lm_lockname *name,

                           struct file *file, struct file_lock *fl);

        /*

         * Client oriented operations

         */

        void (*lm_recovery_done) (void *lockspace, unsigned int jid,

                                  unsigned int message);

        struct module *lm_owner;

};

/*

 * lm_mount() return values

 *

 * ls_jid - the journal ID this node should use

 * ls_first - this node is the first to mount the file system

 * ls_lvb_size - size in bytes of lock value blocks

 * ls_lockspace - lock module's context for this file system

 * ls_ops - lock module's functions

 * ls_flags - lock module features

 */

struct lm_lockstruct {

        unsigned int ls_jid;

        unsigned int ls_first;

        unsigned int ls_lvb_size;

        void *ls_lockspace;

        const struct lm_lockops *ls_ops;

        int ls_flags;

};

/*

 * Lock module bottom interface.  A lock module makes itself available to GFS

 * with these functions.

 */

int gfs2_register_lockproto(const struct lm_lockops *proto);

void gfs2_unregister_lockproto(const struct lm_lockops *proto);

/*

 * Lock module top interface.  GFS calls these functions when mounting or

 * unmounting a file system.

 */

int gfs2_mount_lockproto(char *proto_name, char *table_name, char *host_data,

                         lm_callback_t cb, void *cb_data,

                         unsigned int min_lvb_size, int flags,

                         struct lm_lockstruct *lockstruct,

                         struct kobject *fskobj);

void gfs2_unmount_lockproto(struct lm_lockstruct *lockstruct);

void gfs2_withdraw_lockproto(struct lm_lockstruct *lockstruct);

#endif /* __LM_INTERFACE_DOT_H__ */