+++ /dev/null
-/* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
- * vim:expandtab:shiftwidth=8:tabstop=8:
- *
- * Copyright (c) 2002, 2003 Cluster File Systems, Inc.
- * Author: Peter Braam <braam@clusterfs.com>
- * Author: Phil Schwan <phil@clusterfs.com>
- *
- * This file is part of Lustre, http://www.lustre.org.
- *
- * Lustre is free software; you can redistribute it and/or
- * modify it under the terms of version 2 of the GNU General Public
- * License as published by the Free Software Foundation.
- *
- * Lustre is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with Lustre; if not, write to the Free Software
- * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
- */
-
-#define DEBUG_SUBSYSTEM S_LDLM
-
-#ifdef __KERNEL__
-#include <linux/lustre_dlm.h>
-#include <linux/obd_support.h>
-#include <linux/obd_class.h>
-#include <linux/lustre_lib.h>
-#else
-#include <liblustre.h>
-#endif
-
-static inline int
-ldlm_same_flock_owner(struct ldlm_lock *lock, struct ldlm_lock *new)
-{
- if ((new->l_data.l_flock.pid == lock->l_data.l_flock.pid) &&
- (new->l_export == lock->l_export))
- return 1;
- else
- return 0;
-}
-
-static inline int
-ldlm_flocks_overlap(struct ldlm_lock *lock, struct ldlm_lock *new)
-{
- if ((new->l_data.l_flock.start <= lock->l_data.l_flock.end) &&
- (new->l_data.l_flock.end >= lock->l_data.l_flock.start))
- return 1;
- else
- return 0;
-}
-
-static inline void
-ldlm_flock_destroy(struct ldlm_lock *lock, int flags)
-{
- ENTRY;
-
- list_del_init(&lock->l_res_link);
- if (flags == LDLM_FL_WAIT_NOREPROC) {
- /* client side */
- struct lustre_handle lockh;
-
- /* Set a flag to prevent us from sending a CANCEL */
- lock->l_flags |= LDLM_FL_LOCAL_ONLY;
-
- ldlm_lock2handle(lock, &lockh);
- ldlm_lock_decref_and_cancel(&lockh, lock->l_granted_mode);
- }
-
- ldlm_lock_destroy(lock);
- EXIT;
-}
-
-int
-ldlm_flock_enqueue(struct ldlm_lock **reqp, void *req_cookie, int *flags,
- int first_enq, ldlm_error_t *err)
-{
- struct ldlm_lock *req = *reqp;
- struct ldlm_lock *new = req;
- struct ldlm_lock *new2 = NULL;
- struct ldlm_lock *lock = NULL;
- struct ldlm_resource *res = req->l_resource;
- struct ldlm_namespace *ns = res->lr_namespace;
- struct list_head *tmp;
- struct list_head *ownlocks;
- ldlm_mode_t mode = req->l_req_mode;
- int added = 0;
- int overlaps = 0;
- ENTRY;
-
- CDEBUG(D_FLOCK, "flags: 0x%x pid: %d mode: %d start: %llu end: %llu\n",
- *flags, new->l_data.l_flock.pid, mode,
- req->l_data.l_flock.start, req->l_data.l_flock.end);
-
- *err = ELDLM_OK;
-
- /* No blocking ASTs are sent for record locks */
- req->l_blocking_ast = NULL;
-
- ownlocks = NULL;
- if ((*flags == LDLM_FL_WAIT_NOREPROC) || (mode == LCK_NL)) {
- list_for_each(tmp, &res->lr_granted) {
- lock = list_entry(tmp, struct ldlm_lock, l_res_link);
-
- if (ldlm_same_flock_owner(lock, req)) {
- ownlocks = tmp;
- break;
- }
- }
- } else {
- list_for_each(tmp, &res->lr_granted) {
- lock = list_entry(tmp, struct ldlm_lock, l_res_link);
-
- if (ldlm_same_flock_owner(lock, req)) {
- if (!ownlocks)
- ownlocks = tmp;
- continue;
- }
-
- /* locks are compatible, overlap doesn't matter */
- if (lockmode_compat(lock->l_granted_mode, mode))
- continue;
-
- if (!ldlm_flocks_overlap(lock, req))
- continue;
-
- if (*flags & LDLM_FL_BLOCK_NOWAIT) {
- ldlm_flock_destroy(req, *flags);
- *err = ELDLM_LOCK_ABORTED;
- RETURN(LDLM_ITER_STOP);
- }
-
- if (*flags & LDLM_FL_TEST_LOCK) {
- req->l_granted_mode = lock->l_granted_mode;
- req->l_data.l_flock.pid =
- lock->l_data.l_flock.pid;
- req->l_data.l_flock.start =
- lock->l_data.l_flock.start;
- req->l_data.l_flock.end =
- lock->l_data.l_flock.end;
- ldlm_flock_destroy(req, *flags);
- RETURN(LDLM_ITER_STOP);
- }
-
- if (first_enq) {
- /* XXX - add deadlock detection check here */
- }
-
- *flags |= LDLM_FL_BLOCK_GRANTED;
- RETURN(LDLM_ITER_CONTINUE);
- }
- }
-
- if (*flags & LDLM_FL_TEST_LOCK) {
- LASSERT(first_enq);
- req->l_granted_mode = req->l_req_mode;
- RETURN(LDLM_ITER_STOP);
- }
-
- added = (mode == LCK_NL);
-
- /* Insert the new lock into the list */
-
- if (!ownlocks)
- ownlocks = &res->lr_granted;
-
- for (tmp = ownlocks->next; ownlocks != &res->lr_granted;
- ownlocks = tmp, tmp = ownlocks->next) {
- lock = list_entry(ownlocks, struct ldlm_lock, l_res_link);
-
- if (!ldlm_same_flock_owner(lock, new))
- break;
-
- if (lock->l_granted_mode == mode) {
- if (lock->l_data.l_flock.end <
- (new->l_data.l_flock.start - 1))
- continue;
-
- if (lock->l_data.l_flock.start >
- (new->l_data.l_flock.end + 1))
- break;
-
- if (lock->l_data.l_flock.start >
- new->l_data.l_flock.start)
- lock->l_data.l_flock.start =
- new->l_data.l_flock.start;
- else
- new->l_data.l_flock.start =
- lock->l_data.l_flock.start;
-
- if (lock->l_data.l_flock.end <
- new->l_data.l_flock.end)
- lock->l_data.l_flock.end =
- new->l_data.l_flock.end;
- else
- new->l_data.l_flock.end =
- lock->l_data.l_flock.end;
-
- if (added) {
- ldlm_flock_destroy(lock, *flags);
- } else {
- new = lock;
- added = 1;
- }
- continue;
- }
-
- if (lock->l_data.l_flock.end < new->l_data.l_flock.start)
- continue;
- if (lock->l_data.l_flock.start > new->l_data.l_flock.end)
- break;
-
- ++overlaps;
-
- if (new->l_data.l_flock.start <=
- lock->l_data.l_flock.start) {
- if (new->l_data.l_flock.end <
- lock->l_data.l_flock.end) {
- lock->l_data.l_flock.start =
- new->l_data.l_flock.end + 1;
- break;
- } else if (added) {
- ldlm_flock_destroy(lock, *flags);
- } else {
- lock->l_data.l_flock.start =
- new->l_data.l_flock.start;
- lock->l_data.l_flock.end =
- new->l_data.l_flock.end;
- new = lock;
- added = 1;
- }
- continue;
- }
- if (new->l_data.l_flock.end >= lock->l_data.l_flock.end) {
- lock->l_data.l_flock.end =
- new->l_data.l_flock.start - 1;
- continue;
- }
-
- /* split the existing lock into two locks */
-
- /* if this is an F_UNLCK operation then we could avoid
- * allocating a new lock and use the req lock passed in
- * with the request but this would complicate the reply
- * processing since updates to req get reflected in the
- * reply. The client side must see the original lock data
- * so that it can process the unlock properly. */
-
- /* XXX - if ldlm_lock_new() can sleep we have to
- * release the ns_lock, allocate the new lock, and
- * restart processing this lock. */
- new2 = ldlm_lock_create(ns, NULL, res->lr_name, LDLM_FLOCK,
- lock->l_granted_mode, NULL, NULL);
- if (!new2) {
- /* LBUG for now */
- LASSERT(0);
- RETURN(ENOMEM);
- }
-
- new2->l_granted_mode = lock->l_granted_mode;
- new2->l_data.l_flock.pid = new->l_data.l_flock.pid;
- new2->l_data.l_flock.start = lock->l_data.l_flock.start;
- new2->l_data.l_flock.end = new->l_data.l_flock.start - 1;
- lock->l_data.l_flock.start = new->l_data.l_flock.end + 1;
- new2->l_connh = lock->l_connh;
- if ((new2->l_export = lock->l_export) != NULL) {
- list_add(&new2->l_export_chain,
- &new2->l_export->
- exp_ldlm_data.led_held_locks);
- }
- if (*flags == LDLM_FL_WAIT_NOREPROC) {
- /* client side */
- ldlm_lock_addref_internal(new2, lock->l_granted_mode);
- }
-
- /* insert new2 at lock */
- list_add_tail(&new2->l_res_link, ownlocks);
- LDLM_LOCK_PUT(new2);
- break;
- }
-
- if (added) {
- ldlm_flock_destroy(req, *flags);
- } else {
- /* insert new at ownlocks */
- new->l_granted_mode = new->l_req_mode;
- list_del_init(&new->l_res_link);
- list_add_tail(&new->l_res_link, ownlocks);
- }
-
- if (*flags != LDLM_FL_WAIT_NOREPROC) {
- if (req->l_completion_ast)
- ldlm_add_ast_work_item(req, NULL, NULL, 0);
-
- /* The only problem with doing the reprocessing here is that
- * the completion ASTs for newly granted locks will be sent
- * before the unlock completion is sent. It shouldn't be an
- * issue. Also note that ldlm_flock_enqueue() will recurse,
- * but only once because there can't be unlock requests on
- * the wait queue. */
- if ((mode == LCK_NL) && overlaps)
- ldlm_reprocess_queue(res, &res->lr_waiting);
- }
-
- ldlm_resource_dump(res);
-
- RETURN(LDLM_ITER_CONTINUE);
-}
-
-static void interrupted_flock_completion_wait(void *data)
-{
-}
-
-struct flock_wait_data {
- struct ldlm_lock *fwd_lock;
- int fwd_generation;
-};
-
-int
-ldlm_flock_completion_ast(struct ldlm_lock *lock, int flags, void *data)
-{
- struct ldlm_namespace *ns;
- struct file_lock *getlk = data;
- struct flock_wait_data fwd;
- unsigned long irqflags;
- struct obd_device *obd;
- struct obd_import *imp = NULL;
- ldlm_error_t err;
- int rc = 0;
- struct l_wait_info lwi;
- ENTRY;
-
- LASSERT(flags != LDLM_FL_WAIT_NOREPROC);
-
- if (flags == 0) {
- wake_up(&lock->l_waitq);
- RETURN(0);
- }
-
- if (!(flags & (LDLM_FL_BLOCK_WAIT | LDLM_FL_BLOCK_GRANTED |
- LDLM_FL_BLOCK_CONV)))
- goto granted;
-
- LDLM_DEBUG(lock, "client-side enqueue returned a blocked lock, "
- "sleeping");
-
- ldlm_lock_dump(D_OTHER, lock);
-
- fwd.fwd_lock = lock;
- obd = class_conn2obd(lock->l_connh);
-
- /* if this is a local lock, then there is no import */
- if (obd != NULL)
- imp = obd->u.cli.cl_import;
-
- if (imp != NULL) {
- spin_lock_irqsave(&imp->imp_lock, irqflags);
- fwd.fwd_generation = imp->imp_generation;
- spin_unlock_irqrestore(&imp->imp_lock, irqflags);
- }
-
- lwi = LWI_TIMEOUT_INTR(0, NULL, interrupted_flock_completion_wait,
- &fwd);
-
- /* Go to sleep until the lock is granted. */
- rc = l_wait_event(lock->l_waitq,
- ((lock->l_req_mode == lock->l_granted_mode) ||
- lock->l_destroyed), &lwi);
-
- LASSERT(!(lock->l_destroyed));
-
- if (rc) {
- LDLM_DEBUG(lock, "client-side enqueue waking up: failed (%d)",
- rc);
- RETURN(rc);
- }
-
-granted:
-
- LDLM_DEBUG(lock, "client-side enqueue waking up");
- ns = lock->l_resource->lr_namespace;
- l_lock(&ns->ns_lock);
-
- /* ldlm_lock_enqueue() has already placed lock on the granted list. */
- list_del_init(&lock->l_res_link);
-
- if (getlk) {
- /* fcntl(F_GETLK) request */
- if (lock->l_granted_mode == LCK_PR)
- getlk->fl_type = F_RDLCK;
- else if (lock->l_granted_mode == LCK_PW)
- getlk->fl_type = F_WRLCK;
- else
- getlk->fl_type = F_UNLCK;
- getlk->fl_pid = lock->l_data.l_flock.pid;
- getlk->fl_start = lock->l_data.l_flock.start;
- getlk->fl_end = lock->l_data.l_flock.end;
- /* ldlm_flock_destroy(lock); */
- } else {
- flags = LDLM_FL_WAIT_NOREPROC;
- /* We need to reprocess the lock to do merges or split */
- ldlm_flock_enqueue(&lock, NULL, &flags, 1, &err);
- }
- l_unlock(&ns->ns_lock);
- RETURN(0);
-}
-
-/* This function is only called on the client when a lock is aborted. */
-int
-ldlm_flock_blocking_ast(struct ldlm_lock *lock, struct ldlm_lock_desc *ld,
- void *data, int flag)
-{
- ENTRY;
- ldlm_lock_destroy(lock);
- RETURN(0);
-}
git://git.whamcloud.com / fs / lustre-release.git / commitdiff