--- /dev/null
+/*
+ * 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__ */
+
git://git.onelab.eu / linux-2.6.git / blobdiff