GFS2: Merge lock_dlm module into GFS2

This is the big patch that I've been working on for some time
now. There are many reasons for wanting to make this change
such as:
 o Reducing overhead by eliminating duplicated fields between structures
 o Simplifcation of the code (reduces the code size by a fair bit)
 o The locking interface is now the DLM interface itself as proposed
   some time ago.
 o Fewer lookups of glocks when processing replies from the DLM
 o Fewer memory allocations/deallocations for each glock
 o Scope to do further optimisations in the future (but this patch is
   more than big enough for now!)

Please note that (a) this patch relates to the lock_dlm module and
not the DLM itself, that is still a separate module; and (b) that
we retain the ability to build GFS2 as a standalone single node
filesystem with out requiring the DLM.

This patch needs a lot of testing, hence my keeping it I restarted
my -git tree after the last merge window. That way, this has the maximum
exposure before its merged. This is (modulo a few minor bug fixes) the
same patch that I've been posting on and off the the last three months
and its passed a number of different tests so far.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

1 files changed, 0 insertions, 277 deletions

diff --git a/include/linux/lm_interface.h b/include/linux/lm_interface.h
deleted file mode 100644
index 2ed8fa1b762b..000000000000
--- a/include/linux/lm_interface.h
+++ /dev/null
@@ -1,277 +0,0 @@
-/*
- * 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.
- *
- * LM_MFLAG_CONV_NODROP
- * Do not allow the dlm to internally resolve conversion deadlocks by demoting
- * the lock to unlocked and then reacquiring it in the requested mode. Instead,
- * it should cancel the request and return LM_OUT_CONV_DEADLK.
- */
-
-#define LM_MFLAG_SPECTATOR      0x00000001
-#define LM_MFLAG_CONV_NODROP    0x00000002
-
-/*
- * 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.
- *
- * LM_OUT_CONV_DEADLK
- * The lock request was canceled do to a conversion deadlock.
- */
-
-#define LM_OUT_ST_MASK          0x00000003
-#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_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_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__ */
-