[PATCH 14/16] GFS2: lock_dlm module The lock_dlm module uses a DLM (linux/fs/dlm/) that's external to GFS for inter-node locking. Signed-off-by: David Teigland Signed-off-by: Steven Whitehouse --- fs/gfs2/locking/dlm/Makefile | 3 fs/gfs2/locking/dlm/lock.c | 537 +++++++++++++++++++++++++++++++++++++++++ fs/gfs2/locking/dlm/lock_dlm.h | 191 ++++++++++++++ fs/gfs2/locking/dlm/main.c | 62 ++++ fs/gfs2/locking/dlm/mount.c | 247 ++++++++++++++++++ fs/gfs2/locking/dlm/plock.c | 297 ++++++++++++++++++++++ fs/gfs2/locking/dlm/sysfs.c | 218 ++++++++++++++++ fs/gfs2/locking/dlm/thread.c | 352 ++++++++++++++++++++++++++ include/linux/lock_dlm_plock.h | 40 +++ 9 files changed, 1947 insertions(+) --- /dev/null +++ b/fs/gfs2/locking/dlm/main.c @@ -0,0 +1,62 @@ +/* + * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. + * Copyright (C) 2004-2005 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 v.2. + */ + +#include + +#include "lock_dlm.h" + +extern int gdlm_drop_count; +extern int gdlm_drop_period; + +extern struct lm_lockops gdlm_ops; + +int __init init_lock_dlm(void) +{ + int error; + + error = gfs_register_lockproto(&gdlm_ops); + if (error) { + printk("lock_dlm: can't register protocol: %d\n", error); + return error; + } + + error = gdlm_sysfs_init(); + if (error) { + gfs_unregister_lockproto(&gdlm_ops); + return error; + } + + error = gdlm_plock_init(); + if (error) { + gdlm_sysfs_exit(); + gfs_unregister_lockproto(&gdlm_ops); + return error; + } + + gdlm_drop_count = GDLM_DROP_COUNT; + gdlm_drop_period = GDLM_DROP_PERIOD; + + printk("Lock_DLM (built %s %s) installed\n", __DATE__, __TIME__); + return 0; +} + +void __exit exit_lock_dlm(void) +{ + gdlm_plock_exit(); + gdlm_sysfs_exit(); + gfs_unregister_lockproto(&gdlm_ops); +} + +module_init(init_lock_dlm); +module_exit(exit_lock_dlm); + +MODULE_DESCRIPTION("GFS DLM Locking Module"); +MODULE_AUTHOR("Red Hat, Inc."); +MODULE_LICENSE("GPL"); + --- /dev/null +++ b/fs/gfs2/locking/dlm/lock.c @@ -0,0 +1,537 @@ +/* + * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. + * Copyright (C) 2004-2005 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 v.2. + */ + +#include "lock_dlm.h" + +static char junk_lvb[GDLM_LVB_SIZE]; + +static void queue_complete(struct gdlm_lock *lp) +{ + struct gdlm_ls *ls = lp->ls; + + clear_bit(LFL_ACTIVE, &lp->flags); + + spin_lock(&ls->async_lock); + list_add_tail(&lp->clist, &ls->complete); + spin_unlock(&ls->async_lock); + wake_up(&ls->thread_wait); +} + +static inline void gdlm_ast(void *astarg) +{ + queue_complete((struct gdlm_lock *) astarg); +} + +static inline void gdlm_bast(void *astarg, int mode) +{ + struct gdlm_lock *lp = astarg; + struct gdlm_ls *ls = lp->ls; + + if (!mode) { + printk("lock_dlm: bast mode zero %x,%llx\n", + lp->lockname.ln_type, lp->lockname.ln_number); + return; + } + + spin_lock(&ls->async_lock); + if (!lp->bast_mode) { + list_add_tail(&lp->blist, &ls->blocking); + lp->bast_mode = mode; + } else if (lp->bast_mode < mode) + lp->bast_mode = mode; + spin_unlock(&ls->async_lock); + wake_up(&ls->thread_wait); +} + +void gdlm_queue_delayed(struct gdlm_lock *lp) +{ + struct gdlm_ls *ls = lp->ls; + + spin_lock(&ls->async_lock); + list_add_tail(&lp->delay_list, &ls->delayed); + spin_unlock(&ls->async_lock); +} + +/* convert gfs lock-state to dlm lock-mode */ + +static int16_t make_mode(int16_t lmstate) +{ + switch (lmstate) { + case LM_ST_UNLOCKED: + return DLM_LOCK_NL; + case LM_ST_EXCLUSIVE: + return DLM_LOCK_EX; + case LM_ST_DEFERRED: + return DLM_LOCK_CW; + case LM_ST_SHARED: + return DLM_LOCK_PR; + } + gdlm_assert(0, "unknown LM state %d", lmstate); + return -1; +} + +/* convert dlm lock-mode to gfs lock-state */ + +int16_t gdlm_make_lmstate(int16_t dlmmode) +{ + switch (dlmmode) { + case DLM_LOCK_IV: + case DLM_LOCK_NL: + return LM_ST_UNLOCKED; + case DLM_LOCK_EX: + return LM_ST_EXCLUSIVE; + case DLM_LOCK_CW: + return LM_ST_DEFERRED; + case DLM_LOCK_PR: + return LM_ST_SHARED; + } + gdlm_assert(0, "unknown DLM mode %d", dlmmode); + return -1; +} + +/* verify agreement with GFS on the current lock state, NB: DLM_LOCK_NL and + DLM_LOCK_IV are both considered LM_ST_UNLOCKED by GFS. */ + +static void check_cur_state(struct gdlm_lock *lp, unsigned int cur_state) +{ + int16_t cur = make_mode(cur_state); + if (lp->cur != DLM_LOCK_IV) + gdlm_assert(lp->cur == cur, "%d, %d", lp->cur, cur); +} + +static inline unsigned int make_flags(struct gdlm_lock *lp, + unsigned int gfs_flags, + int16_t cur, int16_t req) +{ + unsigned int lkf = 0; + + if (gfs_flags & LM_FLAG_TRY) + lkf |= DLM_LKF_NOQUEUE; + + if (gfs_flags & LM_FLAG_TRY_1CB) { + lkf |= DLM_LKF_NOQUEUE; + lkf |= DLM_LKF_NOQUEUEBAST; + } + + if (gfs_flags & LM_FLAG_PRIORITY) { + lkf |= DLM_LKF_NOORDER; + lkf |= DLM_LKF_HEADQUE; + } + + if (gfs_flags & LM_FLAG_ANY) { + if (req == DLM_LOCK_PR) + lkf |= DLM_LKF_ALTCW; + else if (req == DLM_LOCK_CW) + lkf |= DLM_LKF_ALTPR; + } + + if (lp->lksb.sb_lkid != 0) { + lkf |= DLM_LKF_CONVERT; + + /* Conversion deadlock avoidance by DLM */ + + if (!test_bit(LFL_FORCE_PROMOTE, &lp->flags) && + !(lkf & DLM_LKF_NOQUEUE) && + cur > DLM_LOCK_NL && req > DLM_LOCK_NL && cur != req) + lkf |= DLM_LKF_CONVDEADLK; + } + + if (lp->lvb) + lkf |= DLM_LKF_VALBLK; + + return lkf; +} + +/* make_strname - convert GFS lock numbers to a string */ + +static inline void make_strname(struct lm_lockname *lockname, + struct gdlm_strname *str) +{ + sprintf(str->name, "%8x%16llx", lockname->ln_type, + lockname->ln_number); + str->namelen = GDLM_STRNAME_BYTES; +} + +int gdlm_create_lp(struct gdlm_ls *ls, struct lm_lockname *name, + struct gdlm_lock **lpp) +{ + struct gdlm_lock *lp; + + lp = kzalloc(sizeof(struct gdlm_lock), GFP_KERNEL); + if (!lp) + return -ENOMEM; + + lp->lockname = *name; + lp->ls = ls; + lp->cur = DLM_LOCK_IV; + lp->lvb = NULL; + lp->hold_null = NULL; + init_completion(&lp->ast_wait); + INIT_LIST_HEAD(&lp->clist); + INIT_LIST_HEAD(&lp->blist); + INIT_LIST_HEAD(&lp->delay_list); + + spin_lock(&ls->async_lock); + list_add(&lp->all_list, &ls->all_locks); + ls->all_locks_count++; + spin_unlock(&ls->async_lock); + + *lpp = lp; + return 0; +} + +void gdlm_delete_lp(struct gdlm_lock *lp) +{ + struct gdlm_ls *ls = lp->ls; + + spin_lock(&ls->async_lock); + if (!list_empty(&lp->clist)) + list_del_init(&lp->clist); + if (!list_empty(&lp->blist)) + list_del_init(&lp->blist); + if (!list_empty(&lp->delay_list)) + list_del_init(&lp->delay_list); + gdlm_assert(!list_empty(&lp->all_list), + "%x,%llx", lp->lockname.ln_type, lp->lockname.ln_number); + list_del_init(&lp->all_list); + ls->all_locks_count--; + spin_unlock(&ls->async_lock); + + kfree(lp); +} + +int gdlm_get_lock(lm_lockspace_t *lockspace, struct lm_lockname *name, + lm_lock_t **lockp) +{ + struct gdlm_lock *lp; + int error; + + error = gdlm_create_lp((struct gdlm_ls *) lockspace, name, &lp); + + *lockp = (lm_lock_t *) lp; + return error; +} + +void gdlm_put_lock(lm_lock_t *lock) +{ + gdlm_delete_lp((struct gdlm_lock *) lock); +} + +unsigned int gdlm_do_lock(struct gdlm_lock *lp, struct dlm_range *range) +{ + struct gdlm_ls *ls = lp->ls; + struct gdlm_strname str; + int error, bast = 1; + + /* + * When recovery is in progress, delay lock requests for submission + * once recovery is done. Requests for recovery (NOEXP) and unlocks + * can pass. + */ + + if (test_bit(DFL_BLOCK_LOCKS, &ls->flags) && + !test_bit(LFL_NOBLOCK, &lp->flags) && lp->req != DLM_LOCK_NL) { + gdlm_queue_delayed(lp); + return LM_OUT_ASYNC; + } + + /* + * Submit the actual lock request. + */ + + if (test_bit(LFL_NOBAST, &lp->flags)) + bast = 0; + + make_strname(&lp->lockname, &str); + + set_bit(LFL_ACTIVE, &lp->flags); + + log_debug("lk %x,%llx id %x %d,%d %x", lp->lockname.ln_type, + lp->lockname.ln_number, lp->lksb.sb_lkid, + lp->cur, lp->req, lp->lkf); + + error = dlm_lock(ls->dlm_lockspace, lp->req, &lp->lksb, lp->lkf, + str.name, str.namelen, 0, gdlm_ast, (void *) lp, + bast ? gdlm_bast : NULL, range); + + if ((error == -EAGAIN) && (lp->lkf & DLM_LKF_NOQUEUE)) { + lp->lksb.sb_status = -EAGAIN; + queue_complete(lp); + error = 0; + } + + if (error) { + log_debug("%s: gdlm_lock %x,%llx err=%d cur=%d req=%d lkf=%x " + "flags=%lx", ls->fsname, lp->lockname.ln_type, + lp->lockname.ln_number, error, lp->cur, lp->req, + lp->lkf, lp->flags); + return LM_OUT_ERROR; + } + return LM_OUT_ASYNC; +} + +unsigned int gdlm_do_unlock(struct gdlm_lock *lp) +{ + struct gdlm_ls *ls = lp->ls; + unsigned int lkf = 0; + int error; + + set_bit(LFL_DLM_UNLOCK, &lp->flags); + set_bit(LFL_ACTIVE, &lp->flags); + + if (lp->lvb) + lkf = DLM_LKF_VALBLK; + + log_debug("un %x,%llx %x %d %x", lp->lockname.ln_type, + lp->lockname.ln_number, lp->lksb.sb_lkid, lp->cur, lkf); + + error = dlm_unlock(ls->dlm_lockspace, lp->lksb.sb_lkid, lkf, NULL, lp); + + if (error) { + log_debug("%s: gdlm_unlock %x,%llx err=%d cur=%d req=%d lkf=%x " + "flags=%lx", ls->fsname, lp->lockname.ln_type, + lp->lockname.ln_number, error, lp->cur, lp->req, + lp->lkf, lp->flags); + return LM_OUT_ERROR; + } + return LM_OUT_ASYNC; +} + +unsigned int gdlm_lock(lm_lock_t *lock, unsigned int cur_state, + unsigned int req_state, unsigned int flags) +{ + struct gdlm_lock *lp = (struct gdlm_lock *) lock; + + clear_bit(LFL_DLM_CANCEL, &lp->flags); + if (flags & LM_FLAG_NOEXP) + set_bit(LFL_NOBLOCK, &lp->flags); + + check_cur_state(lp, cur_state); + lp->req = make_mode(req_state); + lp->lkf = make_flags(lp, flags, lp->cur, lp->req); + + return gdlm_do_lock(lp, NULL); +} + +unsigned int gdlm_unlock(lm_lock_t *lock, unsigned int cur_state) +{ + struct gdlm_lock *lp = (struct gdlm_lock *) lock; + + clear_bit(LFL_DLM_CANCEL, &lp->flags); + if (lp->cur == DLM_LOCK_IV) + return 0; + return gdlm_do_unlock(lp); +} + +void gdlm_cancel(lm_lock_t *lock) +{ + struct gdlm_lock *lp = (struct gdlm_lock *) lock; + struct gdlm_ls *ls = lp->ls; + int error, delay_list = 0; + + if (test_bit(LFL_DLM_CANCEL, &lp->flags)) + return; + + log_info("gdlm_cancel %x,%llx flags %lx", + lp->lockname.ln_type, lp->lockname.ln_number, lp->flags); + + spin_lock(&ls->async_lock); + if (!list_empty(&lp->delay_list)) { + list_del_init(&lp->delay_list); + delay_list = 1; + } + spin_unlock(&ls->async_lock); + + if (delay_list) { + set_bit(LFL_CANCEL, &lp->flags); + set_bit(LFL_ACTIVE, &lp->flags); + queue_complete(lp); + return; + } + + if (!test_bit(LFL_ACTIVE, &lp->flags) || + test_bit(LFL_DLM_UNLOCK, &lp->flags)) { + log_info("gdlm_cancel skip %x,%llx flags %lx", + lp->lockname.ln_type, lp->lockname.ln_number, + lp->flags); + return; + } + + /* the lock is blocked in the dlm */ + + set_bit(LFL_DLM_CANCEL, &lp->flags); + set_bit(LFL_ACTIVE, &lp->flags); + + error = dlm_unlock(ls->dlm_lockspace, lp->lksb.sb_lkid, DLM_LKF_CANCEL, + NULL, lp); + + log_info("gdlm_cancel rv %d %x,%llx flags %lx", error, + lp->lockname.ln_type, lp->lockname.ln_number, lp->flags); + + if (error == -EBUSY) + clear_bit(LFL_DLM_CANCEL, &lp->flags); +} + +int gdlm_add_lvb(struct gdlm_lock *lp) +{ + char *lvb; + + lvb = kzalloc(GDLM_LVB_SIZE, GFP_KERNEL); + if (!lvb) + return -ENOMEM; + + lp->lksb.sb_lvbptr = lvb; + lp->lvb = lvb; + return 0; +} + +void gdlm_del_lvb(struct gdlm_lock *lp) +{ + kfree(lp->lvb); + lp->lvb = NULL; + lp->lksb.sb_lvbptr = NULL; +} + +/* This can do a synchronous dlm request (requiring a lock_dlm thread to get + the completion) because gfs won't call hold_lvb() during a callback (from + the context of a lock_dlm thread). */ + +static int hold_null_lock(struct gdlm_lock *lp) +{ + struct gdlm_lock *lpn = NULL; + int error; + + if (lp->hold_null) { + printk("lock_dlm: lvb already held\n"); + return 0; + } + + error = gdlm_create_lp(lp->ls, &lp->lockname, &lpn); + if (error) + goto out; + + lpn->lksb.sb_lvbptr = junk_lvb; + lpn->lvb = junk_lvb; + + lpn->req = DLM_LOCK_NL; + lpn->lkf = DLM_LKF_VALBLK | DLM_LKF_EXPEDITE; + set_bit(LFL_NOBAST, &lpn->flags); + set_bit(LFL_INLOCK, &lpn->flags); + + init_completion(&lpn->ast_wait); + gdlm_do_lock(lpn, NULL); + wait_for_completion(&lpn->ast_wait); + error = lp->lksb.sb_status; + if (error) { + printk("lock_dlm: hold_null_lock dlm error %d\n", error); + gdlm_delete_lp(lpn); + lpn = NULL; + } + out: + lp->hold_null = lpn; + return error; +} + +/* This cannot do a synchronous dlm request (requiring a lock_dlm thread to get + the completion) because gfs may call unhold_lvb() during a callback (from + the context of a lock_dlm thread) which could cause a deadlock since the + other lock_dlm thread could be engaged in recovery. */ + +static void unhold_null_lock(struct gdlm_lock *lp) +{ + struct gdlm_lock *lpn = lp->hold_null; + + gdlm_assert(lpn, "%x,%llx", + lp->lockname.ln_type, lp->lockname.ln_number); + lpn->lksb.sb_lvbptr = NULL; + lpn->lvb = NULL; + set_bit(LFL_UNLOCK_DELETE, &lpn->flags); + gdlm_do_unlock(lpn); + lp->hold_null = NULL; +} + +/* Acquire a NL lock because gfs requires the value block to remain + intact on the resource while the lvb is "held" even if it's holding no locks + on the resource. */ + +int gdlm_hold_lvb(lm_lock_t *lock, char **lvbp) +{ + struct gdlm_lock *lp = (struct gdlm_lock *) lock; + int error; + + error = gdlm_add_lvb(lp); + if (error) + return error; + + *lvbp = lp->lvb; + + error = hold_null_lock(lp); + if (error) + gdlm_del_lvb(lp); + + return error; +} + +void gdlm_unhold_lvb(lm_lock_t *lock, char *lvb) +{ + struct gdlm_lock *lp = (struct gdlm_lock *) lock; + + unhold_null_lock(lp); + gdlm_del_lvb(lp); +} + +void gdlm_sync_lvb(lm_lock_t *lock, char *lvb) +{ + struct gdlm_lock *lp = (struct gdlm_lock *) lock; + + if (lp->cur != DLM_LOCK_EX) + return; + + init_completion(&lp->ast_wait); + set_bit(LFL_SYNC_LVB, &lp->flags); + + lp->req = DLM_LOCK_EX; + lp->lkf = make_flags(lp, 0, lp->cur, lp->req); + + gdlm_do_lock(lp, NULL); + wait_for_completion(&lp->ast_wait); +} + +void gdlm_submit_delayed(struct gdlm_ls *ls) +{ + struct gdlm_lock *lp, *safe; + + spin_lock(&ls->async_lock); + list_for_each_entry_safe(lp, safe, &ls->delayed, delay_list) { + list_del_init(&lp->delay_list); + list_add_tail(&lp->delay_list, &ls->submit); + } + spin_unlock(&ls->async_lock); + wake_up(&ls->thread_wait); +} + +int gdlm_release_all_locks(struct gdlm_ls *ls) +{ + struct gdlm_lock *lp, *safe; + int count = 0; + + spin_lock(&ls->async_lock); + list_for_each_entry_safe(lp, safe, &ls->all_locks, all_list) { + list_del_init(&lp->all_list); + + if (lp->lvb && lp->lvb != junk_lvb) + kfree(lp->lvb); + kfree(lp); + count++; + } + spin_unlock(&ls->async_lock); + + return count; +} + --- /dev/null +++ b/fs/gfs2/locking/dlm/mount.c @@ -0,0 +1,247 @@ +/* + * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. + * Copyright (C) 2004-2005 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 v.2. + */ + +#include "lock_dlm.h" + +int gdlm_drop_count; +int gdlm_drop_period; +struct lm_lockops gdlm_ops; + + +static struct gdlm_ls *init_gdlm(lm_callback_t cb, lm_fsdata_t *fsdata, + int flags, char *table_name) +{ + struct gdlm_ls *ls; + char buf[256], *p; + + ls = kzalloc(sizeof(struct gdlm_ls), GFP_KERNEL); + if (!ls) + return NULL; + + ls->drop_locks_count = gdlm_drop_count; + ls->drop_locks_period = gdlm_drop_period; + ls->fscb = cb; + ls->fsdata = fsdata; + ls->fsflags = flags; + spin_lock_init(&ls->async_lock); + INIT_LIST_HEAD(&ls->complete); + INIT_LIST_HEAD(&ls->blocking); + INIT_LIST_HEAD(&ls->delayed); + INIT_LIST_HEAD(&ls->submit); + INIT_LIST_HEAD(&ls->all_locks); + init_waitqueue_head(&ls->thread_wait); + init_waitqueue_head(&ls->wait_control); + ls->thread1 = NULL; + ls->thread2 = NULL; + ls->drop_time = jiffies; + ls->jid = -1; + + strncpy(buf, table_name, 256); + buf[255] = '\0'; + + p = strstr(buf, ":"); + if (!p) { + log_info("invalid table_name \"%s\"", table_name); + kfree(ls); + return NULL; + } + *p = '\0'; + p++; + + strncpy(ls->clustername, buf, GDLM_NAME_LEN); + strncpy(ls->fsname, p, GDLM_NAME_LEN); + + return ls; +} + +static int make_args(struct gdlm_ls *ls, char *data_arg) +{ + char data[256]; + char *options, *x, *y; + int error = 0; + + memset(data, 0, 256); + strncpy(data, data_arg, 255); + + for (options = data; (x = strsep(&options, ":")); ) { + if (!*x) + continue; + + y = strchr(x, '='); + if (y) + *y++ = 0; + + if (!strcmp(x, "jid")) { + if (!y) { + log_error("need argument to jid"); + error = -EINVAL; + break; + } + sscanf(y, "%u", &ls->jid); + + } else if (!strcmp(x, "first")) { + if (!y) { + log_error("need argument to first"); + error = -EINVAL; + break; + } + sscanf(y, "%u", &ls->first); + + } else if (!strcmp(x, "id")) { + if (!y) { + log_error("need argument to id"); + error = -EINVAL; + break; + } + sscanf(y, "%u", &ls->id); + + } else { + log_error("unkonwn option: %s", x); + error = -EINVAL; + break; + } + } + + return error; +} + +static int gdlm_mount(char *table_name, char *host_data, + lm_callback_t cb, lm_fsdata_t *fsdata, + unsigned int min_lvb_size, int flags, + struct lm_lockstruct *lockstruct, + struct kobject *fskobj) +{ + struct gdlm_ls *ls; + int error = -ENOMEM; + + if (min_lvb_size > GDLM_LVB_SIZE) + goto out; + + ls = init_gdlm(cb, fsdata, flags, table_name); + if (!ls) + goto out; + + error = gdlm_init_threads(ls); + if (error) + goto out_free; + + error = dlm_new_lockspace(ls->fsname, strlen(ls->fsname), + &ls->dlm_lockspace, 0, GDLM_LVB_SIZE); + if (error) { + log_error("dlm_new_lockspace error %d", error); + goto out_thread; + } + + error = gdlm_kobject_setup(ls, fskobj); + if (error) + goto out_dlm; + + error = make_args(ls, host_data); + if (error) + goto out_sysfs; + + lockstruct->ls_jid = ls->jid; + lockstruct->ls_first = ls->first; + lockstruct->ls_lockspace = ls; + lockstruct->ls_ops = &gdlm_ops; + lockstruct->ls_flags = 0; + lockstruct->ls_lvb_size = GDLM_LVB_SIZE; + return 0; + + out_sysfs: + gdlm_kobject_release(ls); + out_dlm: + dlm_release_lockspace(ls->dlm_lockspace, 2); + out_thread: + gdlm_release_threads(ls); + out_free: + kfree(ls); + out: + return error; +} + +static void gdlm_unmount(lm_lockspace_t *lockspace) +{ + struct gdlm_ls *ls = (struct gdlm_ls *) lockspace; + int rv; + + log_debug("unmount flags %lx", ls->flags); + + /* FIXME: serialize unmount and withdraw in case they + happen at once. Also, if unmount follows withdraw, + wait for withdraw to finish. */ + + if (test_bit(DFL_WITHDRAW, &ls->flags)) + goto out; + + gdlm_kobject_release(ls); + dlm_release_lockspace(ls->dlm_lockspace, 2); + gdlm_release_threads(ls); + rv = gdlm_release_all_locks(ls); + if (rv) + log_info("gdlm_unmount: %d stray locks freed", rv); + out: + kfree(ls); +} + +static void gdlm_recovery_done(lm_lockspace_t *lockspace, unsigned int jid, + unsigned int message) +{ + struct gdlm_ls *ls = (struct gdlm_ls *) lockspace; + ls->recover_jid_done = jid; + kobject_uevent(&ls->kobj, KOBJ_CHANGE, NULL); +} + +static void gdlm_others_may_mount(lm_lockspace_t *lockspace) +{ + struct gdlm_ls *ls = (struct gdlm_ls *) lockspace; + ls->first_done = 1; + kobject_uevent(&ls->kobj, KOBJ_CHANGE, NULL); +} + +/* Userspace gets the offline uevent, blocks new gfs locks on + other mounters, and lets us know (sets WITHDRAW flag). Then, + userspace leaves the mount group while we leave the lockspace. */ + +static void gdlm_withdraw(lm_lockspace_t *lockspace) +{ + struct gdlm_ls *ls = (struct gdlm_ls *) lockspace; + + kobject_uevent(&ls->kobj, KOBJ_OFFLINE, NULL); + + wait_event_interruptible(ls->wait_control, + test_bit(DFL_WITHDRAW, &ls->flags)); + + dlm_release_lockspace(ls->dlm_lockspace, 2); + gdlm_release_threads(ls); + gdlm_release_all_locks(ls); + gdlm_kobject_release(ls); +} + +struct lm_lockops gdlm_ops = { + .lm_proto_name = "lock_dlm", + .lm_mount = gdlm_mount, + .lm_others_may_mount = gdlm_others_may_mount, + .lm_unmount = gdlm_unmount, + .lm_withdraw = gdlm_withdraw, + .lm_get_lock = gdlm_get_lock, + .lm_put_lock = gdlm_put_lock, + .lm_lock = gdlm_lock, + .lm_unlock = gdlm_unlock, + .lm_plock = gdlm_plock, + .lm_punlock = gdlm_punlock, + .lm_plock_get = gdlm_plock_get, + .lm_cancel = gdlm_cancel, + .lm_hold_lvb = gdlm_hold_lvb, + .lm_unhold_lvb = gdlm_unhold_lvb, + .lm_sync_lvb = gdlm_sync_lvb, + .lm_recovery_done = gdlm_recovery_done, + .lm_owner = THIS_MODULE, +}; + --- /dev/null +++ b/fs/gfs2/locking/dlm/plock.c @@ -0,0 +1,297 @@ +/* + * Copyright (C) 2005 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 v.2. + */ + +#include +#include + +#include "lock_dlm.h" + + +static spinlock_t ops_lock; +static struct list_head send_list; +static struct list_head recv_list; +static wait_queue_head_t send_wq; +static wait_queue_head_t recv_wq; + +struct plock_op { + struct list_head list; + int done; + struct gdlm_plock_info info; +}; + +static inline void set_version(struct gdlm_plock_info *info) +{ + info->version[0] = GDLM_PLOCK_VERSION_MAJOR; + info->version[1] = GDLM_PLOCK_VERSION_MINOR; + info->version[2] = GDLM_PLOCK_VERSION_PATCH; +} + +static int check_version(struct gdlm_plock_info *info) +{ + if ((GDLM_PLOCK_VERSION_MAJOR != info->version[0]) || + (GDLM_PLOCK_VERSION_MINOR < info->version[1])) { + log_error("plock device version mismatch: " + "kernel (%u.%u.%u), user (%u.%u.%u)", + GDLM_PLOCK_VERSION_MAJOR, + GDLM_PLOCK_VERSION_MINOR, + GDLM_PLOCK_VERSION_PATCH, + info->version[0], + info->version[1], + info->version[2]); + return -EINVAL; + } + return 0; +} + +static void send_op(struct plock_op *op) +{ + set_version(&op->info); + INIT_LIST_HEAD(&op->list); + spin_lock(&ops_lock); + list_add_tail(&op->list, &send_list); + spin_unlock(&ops_lock); + wake_up(&send_wq); +} + +int gdlm_plock(lm_lockspace_t *lockspace, struct lm_lockname *name, + struct file *file, int cmd, struct file_lock *fl) +{ + struct gdlm_ls *ls = (struct gdlm_ls *) lockspace; + struct plock_op *op; + int rv; + + op = kzalloc(sizeof(*op), GFP_KERNEL); + if (!op) + return -ENOMEM; + + op->info.optype = GDLM_PLOCK_OP_LOCK; + op->info.pid = (uint32_t) fl->fl_owner; + op->info.ex = (fl->fl_type == F_WRLCK); + op->info.wait = IS_SETLKW(cmd); + op->info.fsid = ls->id; + op->info.number = name->ln_number; + op->info.start = fl->fl_start; + op->info.end = fl->fl_end; + + send_op(op); + wait_event(recv_wq, (op->done != 0)); + + spin_lock(&ops_lock); + if (!list_empty(&op->list)) { + printk("plock op on list\n"); + list_del(&op->list); + } + spin_unlock(&ops_lock); + + rv = op->info.rv; + + if (!rv) { + if (posix_lock_file_wait(file, fl) < 0) + log_error("gdlm_plock: vfs lock error %x,%llx", + name->ln_type, name->ln_number); + } + + kfree(op); + return rv; +} + +int gdlm_punlock(lm_lockspace_t *lockspace, struct lm_lockname *name, + struct file *file, struct file_lock *fl) +{ + struct gdlm_ls *ls = (struct gdlm_ls *) lockspace; + struct plock_op *op; + int rv; + + op = kzalloc(sizeof(*op), GFP_KERNEL); + if (!op) + return -ENOMEM; + + if (posix_lock_file_wait(file, fl) < 0) + log_error("gdlm_punlock: vfs unlock error %x,%llx", + name->ln_type, name->ln_number); + + op->info.optype = GDLM_PLOCK_OP_UNLOCK; + op->info.pid = (uint32_t) fl->fl_owner; + op->info.fsid = ls->id; + op->info.number = name->ln_number; + op->info.start = fl->fl_start; + op->info.end = fl->fl_end; + + send_op(op); + wait_event(recv_wq, (op->done != 0)); + + spin_lock(&ops_lock); + if (!list_empty(&op->list)) { + printk("punlock op on list\n"); + list_del(&op->list); + } + spin_unlock(&ops_lock); + + rv = op->info.rv; + + kfree(op); + return rv; +} + +int gdlm_plock_get(lm_lockspace_t *lockspace, struct lm_lockname *name, + struct file *file, struct file_lock *fl) +{ + struct gdlm_ls *ls = (struct gdlm_ls *) lockspace; + struct plock_op *op; + int rv; + + op = kzalloc(sizeof(*op), GFP_KERNEL); + if (!op) + return -ENOMEM; + + op->info.optype = GDLM_PLOCK_OP_GET; + op->info.pid = (uint32_t) fl->fl_owner; + op->info.ex = (fl->fl_type == F_WRLCK); + op->info.fsid = ls->id; + op->info.number = name->ln_number; + op->info.start = fl->fl_start; + op->info.end = fl->fl_end; + + send_op(op); + wait_event(recv_wq, (op->done != 0)); + + spin_lock(&ops_lock); + if (!list_empty(&op->list)) { + printk("plock_get op on list\n"); + list_del(&op->list); + } + spin_unlock(&ops_lock); + + rv = op->info.rv; + + if (rv == 0) + fl->fl_type = F_UNLCK; + else if (rv > 0) { + fl->fl_type = (op->info.ex) ? F_WRLCK : F_RDLCK; + fl->fl_pid = op->info.pid; + fl->fl_start = op->info.start; + fl->fl_end = op->info.end; + } + + kfree(op); + return rv; +} + +/* a read copies out one plock request from the send list */ +static ssize_t dev_read(struct file *file, char __user *u, size_t count, + loff_t *ppos) +{ + struct gdlm_plock_info info; + struct plock_op *op = NULL; + + if (count < sizeof(info)) + return -EINVAL; + + spin_lock(&ops_lock); + if (!list_empty(&send_list)) { + op = list_entry(send_list.next, struct plock_op, list); + list_move(&op->list, &recv_list); + memcpy(&info, &op->info, sizeof(info)); + } + spin_unlock(&ops_lock); + + if (!op) + return -EAGAIN; + + if (copy_to_user(u, &info, sizeof(info))) + return -EFAULT; + return sizeof(info); +} + +/* a write copies in one plock result that should match a plock_op + on the recv list */ +static ssize_t dev_write(struct file *file, const char __user *u, size_t count, + loff_t *ppos) +{ + struct gdlm_plock_info info; + struct plock_op *op; + int found = 0; + + if (count != sizeof(info)) + return -EINVAL; + + if (copy_from_user(&info, u, sizeof(info))) + return -EFAULT; + + if (check_version(&info)) + return -EINVAL; + + spin_lock(&ops_lock); + list_for_each_entry(op, &recv_list, list) { + if (op->info.fsid == info.fsid && + op->info.number == info.number) { + list_del_init(&op->list); + found = 1; + op->done = 1; + memcpy(&op->info, &info, sizeof(info)); + break; + } + } + spin_unlock(&ops_lock); + + if (found) + wake_up(&recv_wq); + else + printk("gdlm dev_write no op %x %llx\n", info.fsid, + info.number); + return count; +} + +static unsigned int dev_poll(struct file *file, poll_table *wait) +{ + poll_wait(file, &send_wq, wait); + + spin_lock(&ops_lock); + if (!list_empty(&send_list)) { + spin_unlock(&ops_lock); + return POLLIN | POLLRDNORM; + } + spin_unlock(&ops_lock); + return 0; +} + +static struct file_operations dev_fops = { + .read = dev_read, + .write = dev_write, + .poll = dev_poll, + .owner = THIS_MODULE +}; + +static struct miscdevice plock_dev_misc = { + .minor = MISC_DYNAMIC_MINOR, + .name = GDLM_PLOCK_MISC_NAME, + .fops = &dev_fops +}; + +int gdlm_plock_init(void) +{ + int rv; + + spin_lock_init(&ops_lock); + INIT_LIST_HEAD(&send_list); + INIT_LIST_HEAD(&recv_list); + init_waitqueue_head(&send_wq); + init_waitqueue_head(&recv_wq); + + rv = misc_register(&plock_dev_misc); + if (rv) + printk("gdlm_plock_init: misc_register failed %d", rv); + return rv; +} + +void gdlm_plock_exit(void) +{ + if (misc_deregister(&plock_dev_misc) < 0) + printk("gdlm_plock_exit: misc_deregister failed"); +} + --- /dev/null +++ b/fs/gfs2/locking/dlm/sysfs.c @@ -0,0 +1,218 @@ +/* + * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. + * Copyright (C) 2004-2005 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 v.2. + */ + +#include +#include + +#include "lock_dlm.h" + +extern struct lm_lockops gdlm_ops; + +static ssize_t proto_name_show(struct gdlm_ls *ls, char *buf) +{ + return sprintf(buf, "%s\n", gdlm_ops.lm_proto_name); +} + +static ssize_t block_show(struct gdlm_ls *ls, char *buf) +{ + ssize_t ret; + int val = 0; + + if (test_bit(DFL_BLOCK_LOCKS, &ls->flags)) + val = 1; + ret = sprintf(buf, "%d\n", val); + return ret; +} + +static ssize_t block_store(struct gdlm_ls *ls, const char *buf, size_t len) +{ + ssize_t ret = len; + int val; + + val = simple_strtol(buf, NULL, 0); + + if (val == 1) + set_bit(DFL_BLOCK_LOCKS, &ls->flags); + else if (val == 0) { + clear_bit(DFL_BLOCK_LOCKS, &ls->flags); + gdlm_submit_delayed(ls); + } else + ret = -EINVAL; + return ret; +} + +static ssize_t withdraw_show(struct gdlm_ls *ls, char *buf) +{ + ssize_t ret; + int val = 0; + + if (test_bit(DFL_WITHDRAW, &ls->flags)) + val = 1; + ret = sprintf(buf, "%d\n", val); + return ret; +} + +static ssize_t withdraw_store(struct gdlm_ls *ls, const char *buf, size_t len) +{ + ssize_t ret = len; + int val; + + val = simple_strtol(buf, NULL, 0); + + if (val == 1) + set_bit(DFL_WITHDRAW, &ls->flags); + else + ret = -EINVAL; + wake_up(&ls->wait_control); + return ret; +} + +static ssize_t id_show(struct gdlm_ls *ls, char *buf) +{ + return sprintf(buf, "%u\n", ls->id); +} + +static ssize_t jid_show(struct gdlm_ls *ls, char *buf) +{ + return sprintf(buf, "%d\n", ls->jid); +} + +static ssize_t first_show(struct gdlm_ls *ls, char *buf) +{ + return sprintf(buf, "%d\n", ls->first); +} + +static ssize_t first_done_show(struct gdlm_ls *ls, char *buf) +{ + return sprintf(buf, "%d\n", ls->first_done); +} + +static ssize_t recover_show(struct gdlm_ls *ls, char *buf) +{ + return sprintf(buf, "%d\n", ls->recover_jid); +} + +static ssize_t recover_store(struct gdlm_ls *ls, const char *buf, size_t len) +{ + ls->recover_jid = simple_strtol(buf, NULL, 0); + ls->fscb(ls->fsdata, LM_CB_NEED_RECOVERY, &ls->recover_jid); + return len; +} + +static ssize_t recover_done_show(struct gdlm_ls *ls, char *buf) +{ + return sprintf(buf, "%d\n", ls->recover_jid_done); +} + +struct gdlm_attr { + struct attribute attr; + ssize_t (*show)(struct gdlm_ls *, char *); + ssize_t (*store)(struct gdlm_ls *, const char *, size_t); +}; + +#define GDLM_ATTR(_name,_mode,_show,_store) \ +static struct gdlm_attr gdlm_attr_##_name = __ATTR(_name,_mode,_show,_store) + +GDLM_ATTR(proto_name, 0444, proto_name_show, NULL); +GDLM_ATTR(block, 0644, block_show, block_store); +GDLM_ATTR(withdraw, 0644, withdraw_show, withdraw_store); +GDLM_ATTR(id, 0444, id_show, NULL); +GDLM_ATTR(jid, 0444, jid_show, NULL); +GDLM_ATTR(first, 0444, first_show, NULL); +GDLM_ATTR(first_done, 0444, first_done_show, NULL); +GDLM_ATTR(recover, 0644, recover_show, recover_store); +GDLM_ATTR(recover_done, 0444, recover_done_show, NULL); + +static struct attribute *gdlm_attrs[] = { + &gdlm_attr_proto_name.attr, + &gdlm_attr_block.attr, + &gdlm_attr_withdraw.attr, + &gdlm_attr_id.attr, + &gdlm_attr_jid.attr, + &gdlm_attr_first.attr, + &gdlm_attr_first_done.attr, + &gdlm_attr_recover.attr, + &gdlm_attr_recover_done.attr, + NULL, +}; + +static ssize_t gdlm_attr_show(struct kobject *kobj, struct attribute *attr, + char *buf) +{ + struct gdlm_ls *ls = container_of(kobj, struct gdlm_ls, kobj); + struct gdlm_attr *a = container_of(attr, struct gdlm_attr, attr); + return a->show ? a->show(ls, buf) : 0; +} + +static ssize_t gdlm_attr_store(struct kobject *kobj, struct attribute *attr, + const char *buf, size_t len) +{ + struct gdlm_ls *ls = container_of(kobj, struct gdlm_ls, kobj); + struct gdlm_attr *a = container_of(attr, struct gdlm_attr, attr); + return a->store ? a->store(ls, buf, len) : len; +} + +static struct sysfs_ops gdlm_attr_ops = { + .show = gdlm_attr_show, + .store = gdlm_attr_store, +}; + +static struct kobj_type gdlm_ktype = { + .default_attrs = gdlm_attrs, + .sysfs_ops = &gdlm_attr_ops, +}; + +static struct kset gdlm_kset = { + .subsys = &kernel_subsys, + .kobj = {.name = "lock_dlm",}, + .ktype = &gdlm_ktype, +}; + +int gdlm_kobject_setup(struct gdlm_ls *ls, struct kobject *fskobj) +{ + int error; + + error = kobject_set_name(&ls->kobj, "%s", "lock_module"); + if (error) { + log_error("can't set kobj name %d", error); + return error; + } + + ls->kobj.kset = &gdlm_kset; + ls->kobj.ktype = &gdlm_ktype; + ls->kobj.parent = fskobj; + + error = kobject_register(&ls->kobj); + if (error) + log_error("can't register kobj %d", error); + + return error; +} + +void gdlm_kobject_release(struct gdlm_ls *ls) +{ + kobject_unregister(&ls->kobj); +} + +int gdlm_sysfs_init(void) +{ + int error; + + error = kset_register(&gdlm_kset); + if (error) + printk("lock_dlm: cannot register kset %d\n", error); + + return error; +} + +void gdlm_sysfs_exit(void) +{ + kset_unregister(&gdlm_kset); +} + --- /dev/null +++ b/fs/gfs2/locking/dlm/thread.c @@ -0,0 +1,352 @@ +/* + * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. + * Copyright (C) 2004-2005 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 v.2. + */ + +#include "lock_dlm.h" + +/* A lock placed on this queue is re-submitted to DLM as soon as the lock_dlm + thread gets to it. */ + +static void queue_submit(struct gdlm_lock *lp) +{ + struct gdlm_ls *ls = lp->ls; + + spin_lock(&ls->async_lock); + list_add_tail(&lp->delay_list, &ls->submit); + spin_unlock(&ls->async_lock); + wake_up(&ls->thread_wait); +} + +static void process_blocking(struct gdlm_lock *lp, int bast_mode) +{ + struct gdlm_ls *ls = lp->ls; + unsigned int cb = 0; + + switch (gdlm_make_lmstate(bast_mode)) { + case LM_ST_EXCLUSIVE: + cb = LM_CB_NEED_E; + break; + case LM_ST_DEFERRED: + cb = LM_CB_NEED_D; + break; + case LM_ST_SHARED: + cb = LM_CB_NEED_S; + break; + default: + gdlm_assert(0, "unknown bast mode %u", lp->bast_mode); + } + + ls->fscb(ls->fsdata, cb, &lp->lockname); +} + +static void process_complete(struct gdlm_lock *lp) +{ + struct gdlm_ls *ls = lp->ls; + struct lm_async_cb acb; + int16_t prev_mode = lp->cur; + + memset(&acb, 0, sizeof(acb)); + + if (lp->lksb.sb_status == -DLM_ECANCEL) { + log_info("complete dlm cancel %x,%llx flags %lx", + lp->lockname.ln_type, lp->lockname.ln_number, + lp->flags); + + lp->req = lp->cur; + acb.lc_ret |= LM_OUT_CANCELED; + if (lp->cur == DLM_LOCK_IV) + lp->lksb.sb_lkid = 0; + goto out; + } + + if (test_and_clear_bit(LFL_DLM_UNLOCK, &lp->flags)) { + if (lp->lksb.sb_status != -DLM_EUNLOCK) { + log_info("unlock sb_status %d %x,%llx flags %lx", + lp->lksb.sb_status, lp->lockname.ln_type, + lp->lockname.ln_number, lp->flags); + return; + } + + lp->cur = DLM_LOCK_IV; + lp->req = DLM_LOCK_IV; + lp->lksb.sb_lkid = 0; + + if (test_and_clear_bit(LFL_UNLOCK_DELETE, &lp->flags)) { + gdlm_delete_lp(lp); + return; + } + goto out; + } + + if (lp->lksb.sb_flags & DLM_SBF_VALNOTVALID) + memset(lp->lksb.sb_lvbptr, 0, GDLM_LVB_SIZE); + + if (lp->lksb.sb_flags & DLM_SBF_ALTMODE) { + if (lp->req == DLM_LOCK_PR) + lp->req = DLM_LOCK_CW; + else if (lp->req == DLM_LOCK_CW) + lp->req = DLM_LOCK_PR; + } + + /* + * A canceled lock request. The lock was just taken off the delayed + * list and was never even submitted to dlm. + */ + + if (test_and_clear_bit(LFL_CANCEL, &lp->flags)) { + log_info("complete internal cancel %x,%llx", + lp->lockname.ln_type, lp->lockname.ln_number); + lp->req = lp->cur; + acb.lc_ret |= LM_OUT_CANCELED; + goto out; + } + + /* + * An error occured. + */ + + if (lp->lksb.sb_status) { + /* a "normal" error */ + if ((lp->lksb.sb_status == -EAGAIN) && + (lp->lkf & DLM_LKF_NOQUEUE)) { + lp->req = lp->cur; + if (lp->cur == DLM_LOCK_IV) + lp->lksb.sb_lkid = 0; + goto out; + } + + /* this could only happen with cancels I think */ + log_info("ast sb_status %d %x,%llx flags %lx", + lp->lksb.sb_status, lp->lockname.ln_type, + lp->lockname.ln_number, lp->flags); + return; + } + + /* + * This is an AST for an EX->EX conversion for sync_lvb from GFS. + */ + + if (test_and_clear_bit(LFL_SYNC_LVB, &lp->flags)) { + complete(&lp->ast_wait); + return; + } + + /* + * A lock has been demoted to NL because it initially completed during + * BLOCK_LOCKS. Now it must be requested in the originally requested + * mode. + */ + + if (test_and_clear_bit(LFL_REREQUEST, &lp->flags)) { + gdlm_assert(lp->req == DLM_LOCK_NL, "%x,%llx", + lp->lockname.ln_type, lp->lockname.ln_number); + gdlm_assert(lp->prev_req > DLM_LOCK_NL, "%x,%llx", + lp->lockname.ln_type, lp->lockname.ln_number); + + lp->cur = DLM_LOCK_NL; + lp->req = lp->prev_req; + lp->prev_req = DLM_LOCK_IV; + lp->lkf &= ~DLM_LKF_CONVDEADLK; + + set_bit(LFL_NOCACHE, &lp->flags); + + if (test_bit(DFL_BLOCK_LOCKS, &ls->flags) && + !test_bit(LFL_NOBLOCK, &lp->flags)) + gdlm_queue_delayed(lp); + else + queue_submit(lp); + return; + } + + /* + * A request is granted during dlm recovery. It may be granted + * because the locks of a failed node were cleared. In that case, + * there may be inconsistent data beneath this lock and we must wait + * for recovery to complete to use it. When gfs recovery is done this + * granted lock will be converted to NL and then reacquired in this + * granted state. + */ + + if (test_bit(DFL_BLOCK_LOCKS, &ls->flags) && + !test_bit(LFL_NOBLOCK, &lp->flags) && + lp->req != DLM_LOCK_NL) { + + lp->cur = lp->req; + lp->prev_req = lp->req; + lp->req = DLM_LOCK_NL; + lp->lkf |= DLM_LKF_CONVERT; + lp->lkf &= ~DLM_LKF_CONVDEADLK; + + log_debug("rereq %x,%llx id %x %d,%d", + lp->lockname.ln_type, lp->lockname.ln_number, + lp->lksb.sb_lkid, lp->cur, lp->req); + + set_bit(LFL_REREQUEST, &lp->flags); + queue_submit(lp); + return; + } + + /* + * DLM demoted the lock to NL before it was granted so GFS must be + * told it cannot cache data for this lock. + */ + + if (lp->lksb.sb_flags & DLM_SBF_DEMOTED) + set_bit(LFL_NOCACHE, &lp->flags); + + out: + /* + * This is an internal lock_dlm lock + */ + + if (test_bit(LFL_INLOCK, &lp->flags)) { + clear_bit(LFL_NOBLOCK, &lp->flags); + lp->cur = lp->req; + complete(&lp->ast_wait); + return; + } + + /* + * Normal completion of a lock request. Tell GFS it now has the lock. + */ + + clear_bit(LFL_NOBLOCK, &lp->flags); + lp->cur = lp->req; + + acb.lc_name = lp->lockname; + acb.lc_ret |= gdlm_make_lmstate(lp->cur); + + if (!test_and_clear_bit(LFL_NOCACHE, &lp->flags) && + (lp->cur > DLM_LOCK_NL) && (prev_mode > DLM_LOCK_NL)) + acb.lc_ret |= LM_OUT_CACHEABLE; + + ls->fscb(ls->fsdata, LM_CB_ASYNC, &acb); +} + +static inline int no_work(struct gdlm_ls *ls, int blocking) +{ + int ret; + + spin_lock(&ls->async_lock); + ret = list_empty(&ls->complete) && list_empty(&ls->submit); + if (ret && blocking) + ret = list_empty(&ls->blocking); + spin_unlock(&ls->async_lock); + + return ret; +} + +static inline int check_drop(struct gdlm_ls *ls) +{ + if (!ls->drop_locks_count) + return 0; + + if (time_after(jiffies, ls->drop_time + ls->drop_locks_period * HZ)) { + ls->drop_time = jiffies; + if (ls->all_locks_count >= ls->drop_locks_count) + return 1; + } + return 0; +} + +static int gdlm_thread(void *data) +{ + struct gdlm_ls *ls = (struct gdlm_ls *) data; + struct gdlm_lock *lp = NULL; + int blist = 0; + uint8_t complete, blocking, submit, drop; + DECLARE_WAITQUEUE(wait, current); + + /* Only thread1 is allowed to do blocking callbacks since gfs + may wait for a completion callback within a blocking cb. */ + + if (current == ls->thread1) + blist = 1; + + while (!kthread_should_stop()) { + set_current_state(TASK_INTERRUPTIBLE); + add_wait_queue(&ls->thread_wait, &wait); + if (no_work(ls, blist)) + schedule(); + remove_wait_queue(&ls->thread_wait, &wait); + set_current_state(TASK_RUNNING); + + complete = blocking = submit = drop = 0; + + spin_lock(&ls->async_lock); + + if (blist && !list_empty(&ls->blocking)) { + lp = list_entry(ls->blocking.next, struct gdlm_lock, + blist); + list_del_init(&lp->blist); + blocking = lp->bast_mode; + lp->bast_mode = 0; + } else if (!list_empty(&ls->complete)) { + lp = list_entry(ls->complete.next, struct gdlm_lock, + clist); + list_del_init(&lp->clist); + complete = 1; + } else if (!list_empty(&ls->submit)) { + lp = list_entry(ls->submit.next, struct gdlm_lock, + delay_list); + list_del_init(&lp->delay_list); + submit = 1; + } + + drop = check_drop(ls); + spin_unlock(&ls->async_lock); + + if (complete) + process_complete(lp); + + else if (blocking) + process_blocking(lp, blocking); + + else if (submit) + gdlm_do_lock(lp, NULL); + + if (drop) + ls->fscb(ls->fsdata, LM_CB_DROPLOCKS, NULL); + + schedule(); + } + + return 0; +} + +int gdlm_init_threads(struct gdlm_ls *ls) +{ + struct task_struct *p; + int error; + + p = kthread_run(gdlm_thread, ls, "lock_dlm1"); + error = IS_ERR(p); + if (error) { + log_error("can't start lock_dlm1 thread %d", error); + return error; + } + ls->thread1 = p; + + p = kthread_run(gdlm_thread, ls, "lock_dlm2"); + error = IS_ERR(p); + if (error) { + log_error("can't start lock_dlm2 thread %d", error); + kthread_stop(ls->thread1); + return error; + } + ls->thread2 = p; + + return 0; +} + +void gdlm_release_threads(struct gdlm_ls *ls) +{ + kthread_stop(ls->thread1); + kthread_stop(ls->thread2); +} + --- /dev/null +++ b/fs/gfs2/locking/dlm/lock_dlm.h @@ -0,0 +1,191 @@ +/* + * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. + * Copyright (C) 2004-2005 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 v.2. + */ + +#ifndef LOCK_DLM_DOT_H +#define LOCK_DLM_DOT_H + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include "../../lm_interface.h" + +/* + * Internally, we prefix things with gdlm_ and GDLM_ (for gfs-dlm) since a + * prefix of lock_dlm_ gets awkward. Externally, GFS refers to this module + * as "lock_dlm". + */ + +#define GDLM_STRNAME_BYTES 24 +#define GDLM_LVB_SIZE 32 +#define GDLM_DROP_COUNT 50000 +#define GDLM_DROP_PERIOD 60 +#define GDLM_NAME_LEN 128 + +/* GFS uses 12 bytes to identify a resource (32 bit type + 64 bit number). + We sprintf these numbers into a 24 byte string of hex values to make them + human-readable (to make debugging simpler.) */ + +struct gdlm_strname { + unsigned char name[GDLM_STRNAME_BYTES]; + unsigned short namelen; +}; + +enum { + DFL_BLOCK_LOCKS = 0, + DFL_SPECTATOR = 1, + DFL_WITHDRAW = 2, +}; + +struct gdlm_ls { + uint32_t id; + int jid; + int first; + int first_done; + unsigned long flags; + struct kobject kobj; + char clustername[GDLM_NAME_LEN]; + char fsname[GDLM_NAME_LEN]; + int fsflags; + dlm_lockspace_t *dlm_lockspace; + lm_callback_t fscb; + lm_fsdata_t *fsdata; + int recover_jid; + int recover_jid_done; + spinlock_t async_lock; + struct list_head complete; + struct list_head blocking; + struct list_head delayed; + struct list_head submit; + struct list_head all_locks; + uint32_t all_locks_count; + wait_queue_head_t wait_control; + struct task_struct *thread1; + struct task_struct *thread2; + wait_queue_head_t thread_wait; + unsigned long drop_time; + int drop_locks_count; + int drop_locks_period; +}; + +enum { + LFL_NOBLOCK = 0, + LFL_NOCACHE = 1, + LFL_DLM_UNLOCK = 2, + LFL_DLM_CANCEL = 3, + LFL_SYNC_LVB = 4, + LFL_FORCE_PROMOTE = 5, + LFL_REREQUEST = 6, + LFL_ACTIVE = 7, + LFL_INLOCK = 8, + LFL_CANCEL = 9, + LFL_NOBAST = 10, + LFL_HEADQUE = 11, + LFL_UNLOCK_DELETE = 12, +}; + +struct gdlm_lock { + struct gdlm_ls *ls; + struct lm_lockname lockname; + char *lvb; + struct dlm_lksb lksb; + + int16_t cur; + int16_t req; + int16_t prev_req; + uint32_t lkf; /* dlm flags DLM_LKF_ */ + unsigned long flags; /* lock_dlm flags LFL_ */ + + int bast_mode; /* protected by async_lock */ + struct completion ast_wait; + + struct list_head clist; /* complete */ + struct list_head blist; /* blocking */ + struct list_head delay_list; /* delayed */ + struct list_head all_list; /* all locks for the fs */ + struct gdlm_lock *hold_null; /* NL lock for hold_lvb */ +}; + +#define gdlm_assert(assertion, fmt, args...) \ +do { \ + if (unlikely(!(assertion))) { \ + printk(KERN_EMERG "lock_dlm: fatal assertion failed \"%s\"\n" \ + "lock_dlm: " fmt "\n", \ + #assertion, ##args); \ + BUG(); \ + } \ +} while (0) + +#define log_print(lev, fmt, arg...) printk(lev "lock_dlm: " fmt "\n" , ## arg) +#define log_info(fmt, arg...) log_print(KERN_INFO , fmt , ## arg) +#define log_error(fmt, arg...) log_print(KERN_ERR , fmt , ## arg) +#ifdef LOCK_DLM_LOG_DEBUG +#define log_debug(fmt, arg...) log_print(KERN_DEBUG , fmt , ## arg) +#else +#define log_debug(fmt, arg...) +#endif + +/* sysfs.c */ + +int gdlm_sysfs_init(void); +void gdlm_sysfs_exit(void); +int gdlm_kobject_setup(struct gdlm_ls *, struct kobject *); +void gdlm_kobject_release(struct gdlm_ls *); + +/* thread.c */ + +int gdlm_init_threads(struct gdlm_ls *); +void gdlm_release_threads(struct gdlm_ls *); + +/* lock.c */ + +int16_t gdlm_make_lmstate(int16_t); +void gdlm_queue_delayed(struct gdlm_lock *); +void gdlm_submit_delayed(struct gdlm_ls *); +int gdlm_release_all_locks(struct gdlm_ls *); +int gdlm_create_lp(struct gdlm_ls *, struct lm_lockname *, struct gdlm_lock **); +void gdlm_delete_lp(struct gdlm_lock *); +int gdlm_add_lvb(struct gdlm_lock *); +void gdlm_del_lvb(struct gdlm_lock *); +unsigned int gdlm_do_lock(struct gdlm_lock *, struct dlm_range *); +unsigned int gdlm_do_unlock(struct gdlm_lock *); + +int gdlm_get_lock(lm_lockspace_t *, struct lm_lockname *, lm_lock_t **); +void gdlm_put_lock(lm_lock_t *); +unsigned int gdlm_lock(lm_lock_t *, unsigned int, unsigned int, unsigned int); +unsigned int gdlm_unlock(lm_lock_t *, unsigned int); +void gdlm_cancel(lm_lock_t *); +int gdlm_hold_lvb(lm_lock_t *, char **); +void gdlm_unhold_lvb(lm_lock_t *, char *); +void gdlm_sync_lvb(lm_lock_t *, char *); + +/* plock.c */ + +int gdlm_plock_init(void); +void gdlm_plock_exit(void); +int gdlm_plock(lm_lockspace_t *, struct lm_lockname *, struct file *, int, + struct file_lock *); +int gdlm_plock_get(lm_lockspace_t *, struct lm_lockname *, struct file *, + struct file_lock *); +int gdlm_punlock(lm_lockspace_t *, struct lm_lockname *, struct file *, + struct file_lock *); +#endif + --- /dev/null +++ b/fs/gfs2/locking/dlm/Makefile @@ -0,0 +1,3 @@ +obj-$(CONFIG_GFS2_FS) += lock_dlm.o +lock_dlm-y := lock.o main.o mount.o sysfs.o thread.o plock.o + --- /dev/null +++ b/include/linux/lock_dlm_plock.h @@ -0,0 +1,40 @@ +/* + * Copyright (C) 2005 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 v.2. + */ + +#ifndef __LOCK_DLM_PLOCK_DOT_H__ +#define __LOCK_DLM_PLOCK_DOT_H__ + +#define GDLM_PLOCK_MISC_NAME "lock_dlm_plock" + +#define GDLM_PLOCK_VERSION_MAJOR 1 +#define GDLM_PLOCK_VERSION_MINOR 0 +#define GDLM_PLOCK_VERSION_PATCH 0 + +enum { + GDLM_PLOCK_OP_LOCK = 1, + GDLM_PLOCK_OP_UNLOCK, + GDLM_PLOCK_OP_GET, +}; + +struct gdlm_plock_info { + __u32 version[3]; + __u8 optype; + __u8 ex; + __u8 wait; + __u8 pad; + __u32 pid; + __s32 nodeid; + __s32 rv; + __u32 fsid; + __u64 number; + __u64 start; + __u64 end; +}; + +#endif +