From f057f6cdf64175db1151b1f5d110e29904f119a1 Mon Sep 17 00:00:00 2001 From: Steven Whitehouse Date: Mon, 12 Jan 2009 10:43:39 +0000 Subject: 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 --- fs/gfs2/locking.c | 314 ------------------------------------------------------ 1 file changed, 314 deletions(-) delete mode 100644 fs/gfs2/locking.c (limited to 'fs/gfs2/locking.c') diff --git a/fs/gfs2/locking.c b/fs/gfs2/locking.c deleted file mode 100644 index d3657bc7938a..000000000000 --- a/fs/gfs2/locking.c +++ /dev/null @@ -1,314 +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. - */ - -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include - -struct lmh_wrapper { - struct list_head lw_list; - const struct lm_lockops *lw_ops; -}; - -struct nolock_lockspace { - unsigned int nl_lvb_size; -}; - -/** - * nolock_get_lock - get a lm_lock_t given a descripton of the lock - * @lockspace: the lockspace the lock lives in - * @name: the name of the lock - * @lockp: return the lm_lock_t here - * - * Returns: 0 on success, -EXXX on failure - */ - -static int nolock_get_lock(void *lockspace, struct lm_lockname *name, - void **lockp) -{ - *lockp = lockspace; - return 0; -} - -/** - * nolock_put_lock - get rid of a lock structure - * @lock: the lock to throw away - * - */ - -static void nolock_put_lock(void *lock) -{ -} - -/** - * nolock_hold_lvb - hold on to a lock value block - * @lock: the lock the LVB is associated with - * @lvbp: return the lm_lvb_t here - * - * Returns: 0 on success, -EXXX on failure - */ - -static int nolock_hold_lvb(void *lock, char **lvbp) -{ - struct nolock_lockspace *nl = lock; - int error = 0; - - *lvbp = kzalloc(nl->nl_lvb_size, GFP_KERNEL); - if (!*lvbp) - error = -ENOMEM; - - return error; -} - -/** - * nolock_unhold_lvb - release a LVB - * @lock: the lock the LVB is associated with - * @lvb: the lock value block - * - */ - -static void nolock_unhold_lvb(void *lock, char *lvb) -{ - kfree(lvb); -} - -static int nolock_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); -static void nolock_unmount(void *lockspace); - -/* List of registered low-level locking protocols. A file system selects one - of them by name at mount time, e.g. lock_nolock, lock_dlm. */ - -static const struct lm_lockops nolock_ops = { - .lm_proto_name = "lock_nolock", - .lm_mount = nolock_mount, - .lm_unmount = nolock_unmount, - .lm_get_lock = nolock_get_lock, - .lm_put_lock = nolock_put_lock, - .lm_hold_lvb = nolock_hold_lvb, - .lm_unhold_lvb = nolock_unhold_lvb, -}; - -static struct lmh_wrapper nolock_proto = { - .lw_list = LIST_HEAD_INIT(nolock_proto.lw_list), - .lw_ops = &nolock_ops, -}; - -static LIST_HEAD(lmh_list); -static DEFINE_MUTEX(lmh_lock); - -static int nolock_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) -{ - char *c; - unsigned int jid; - struct nolock_lockspace *nl; - - c = strstr(host_data, "jid="); - if (!c) - jid = 0; - else { - c += 4; - sscanf(c, "%u", &jid); - } - - nl = kzalloc(sizeof(struct nolock_lockspace), GFP_KERNEL); - if (!nl) - return -ENOMEM; - - nl->nl_lvb_size = min_lvb_size; - - lockstruct->ls_jid = jid; - lockstruct->ls_first = 1; - lockstruct->ls_lvb_size = min_lvb_size; - lockstruct->ls_lockspace = nl; - lockstruct->ls_ops = &nolock_ops; - lockstruct->ls_flags = LM_LSFLAG_LOCAL; - - return 0; -} - -static void nolock_unmount(void *lockspace) -{ - struct nolock_lockspace *nl = lockspace; - kfree(nl); -} - -/** - * gfs2_register_lockproto - Register a low-level locking protocol - * @proto: the protocol definition - * - * Returns: 0 on success, -EXXX on failure - */ - -int gfs2_register_lockproto(const struct lm_lockops *proto) -{ - struct lmh_wrapper *lw; - - mutex_lock(&lmh_lock); - - list_for_each_entry(lw, &lmh_list, lw_list) { - if (!strcmp(lw->lw_ops->lm_proto_name, proto->lm_proto_name)) { - mutex_unlock(&lmh_lock); - printk(KERN_INFO "GFS2: protocol %s already exists\n", - proto->lm_proto_name); - return -EEXIST; - } - } - - lw = kzalloc(sizeof(struct lmh_wrapper), GFP_KERNEL); - if (!lw) { - mutex_unlock(&lmh_lock); - return -ENOMEM; - } - - lw->lw_ops = proto; - list_add(&lw->lw_list, &lmh_list); - - mutex_unlock(&lmh_lock); - - return 0; -} - -/** - * gfs2_unregister_lockproto - Unregister a low-level locking protocol - * @proto: the protocol definition - * - */ - -void gfs2_unregister_lockproto(const struct lm_lockops *proto) -{ - struct lmh_wrapper *lw; - - mutex_lock(&lmh_lock); - - list_for_each_entry(lw, &lmh_list, lw_list) { - if (!strcmp(lw->lw_ops->lm_proto_name, proto->lm_proto_name)) { - list_del(&lw->lw_list); - mutex_unlock(&lmh_lock); - kfree(lw); - return; - } - } - - mutex_unlock(&lmh_lock); - - printk(KERN_WARNING "GFS2: can't unregister lock protocol %s\n", - proto->lm_proto_name); -} - -/** - * gfs2_mount_lockproto - Mount a lock protocol - * @proto_name - the name of the protocol - * @table_name - the name of the lock space - * @host_data - data specific to this host - * @cb - the callback to the code using the lock module - * @sdp - The GFS2 superblock - * @min_lvb_size - the mininum LVB size that the caller can deal with - * @flags - LM_MFLAG_* - * @lockstruct - a structure returned describing the mount - * - * Returns: 0 on success, -EXXX on failure - */ - -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) -{ - struct lmh_wrapper *lw = NULL; - int try = 0; - int error, found; - - -retry: - mutex_lock(&lmh_lock); - - if (list_empty(&nolock_proto.lw_list)) - list_add(&nolock_proto.lw_list, &lmh_list); - - found = 0; - list_for_each_entry(lw, &lmh_list, lw_list) { - if (!strcmp(lw->lw_ops->lm_proto_name, proto_name)) { - found = 1; - break; - } - } - - if (!found) { - if (!try && capable(CAP_SYS_MODULE)) { - try = 1; - mutex_unlock(&lmh_lock); - request_module(proto_name); - goto retry; - } - printk(KERN_INFO "GFS2: can't find protocol %s\n", proto_name); - error = -ENOENT; - goto out; - } - - if (lw->lw_ops->lm_owner && - !try_module_get(lw->lw_ops->lm_owner)) { - try = 0; - mutex_unlock(&lmh_lock); - msleep(1000); - goto retry; - } - - error = lw->lw_ops->lm_mount(table_name, host_data, cb, cb_data, - min_lvb_size, flags, lockstruct, fskobj); - if (error) - module_put(lw->lw_ops->lm_owner); -out: - mutex_unlock(&lmh_lock); - return error; -} - -void gfs2_unmount_lockproto(struct lm_lockstruct *lockstruct) -{ - mutex_lock(&lmh_lock); - if (lockstruct->ls_ops->lm_unmount) - lockstruct->ls_ops->lm_unmount(lockstruct->ls_lockspace); - if (lockstruct->ls_ops->lm_owner) - module_put(lockstruct->ls_ops->lm_owner); - mutex_unlock(&lmh_lock); -} - -/** - * gfs2_withdraw_lockproto - abnormally unmount a lock module - * @lockstruct: the lockstruct passed into mount - * - */ - -void gfs2_withdraw_lockproto(struct lm_lockstruct *lockstruct) -{ - mutex_lock(&lmh_lock); - lockstruct->ls_ops->lm_withdraw(lockstruct->ls_lockspace); - if (lockstruct->ls_ops->lm_owner) - module_put(lockstruct->ls_ops->lm_owner); - mutex_unlock(&lmh_lock); -} - -EXPORT_SYMBOL_GPL(gfs2_register_lockproto); -EXPORT_SYMBOL_GPL(gfs2_unregister_lockproto); - -- cgit v1.2.3