diff options
Diffstat (limited to 'drivers/staging/lustre/lustre/ldlm/ldlm_flock.c')
| -rw-r--r-- | drivers/staging/lustre/lustre/ldlm/ldlm_flock.c | 849 |
1 files changed, 849 insertions, 0 deletions
diff --git a/drivers/staging/lustre/lustre/ldlm/ldlm_flock.c b/drivers/staging/lustre/lustre/ldlm/ldlm_flock.c new file mode 100644 index 000000000000..f100a84bde73 --- /dev/null +++ b/drivers/staging/lustre/lustre/ldlm/ldlm_flock.c @@ -0,0 +1,849 @@ +/* + * GPL HEADER START + * + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 only, + * as published by the Free Software Foundation. + * + * This program 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 version 2 for more details (a copy is included + * in the LICENSE file that accompanied this code). + * + * You should have received a copy of the GNU General Public License + * version 2 along with this program; If not, see + * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf + * + * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, + * CA 95054 USA or visit www.sun.com if you need additional information or + * have any questions. + * + * GPL HEADER END + */ +/* + * Copyright (c) 2003 Hewlett-Packard Development Company LP. + * Developed under the sponsorship of the US Government under + * Subcontract No. B514193 + * + * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved. + * Use is subject to license terms. + * + * Copyright (c) 2010, 2012, Intel Corporation. + */ +/* + * This file is part of Lustre, http://www.lustre.org/ + * Lustre is a trademark of Sun Microsystems, Inc. + */ + +/** + * This file implements POSIX lock type for Lustre. + * Its policy properties are start and end of extent and PID. + * + * These locks are only done through MDS due to POSIX semantics requiring + * e.g. that locks could be only partially released and as such split into + * two parts, and also that two adjacent locks from the same process may be + * merged into a single wider lock. + * + * Lock modes are mapped like this: + * PR and PW for READ and WRITE locks + * NL to request a releasing of a portion of the lock + * + * These flock locks never timeout. + */ + +#define DEBUG_SUBSYSTEM S_LDLM + +#include <lustre_dlm.h> +#include <obd_support.h> +#include <obd_class.h> +#include <lustre_lib.h> +#include <linux/list.h> + +#include "ldlm_internal.h" + +int ldlm_flock_blocking_ast(struct ldlm_lock *lock, struct ldlm_lock_desc *desc, + void *data, int flag); + +/** + * list_for_remaining_safe - iterate over the remaining entries in a list + * and safeguard against removal of a list entry. + * \param pos the &struct list_head to use as a loop counter. pos MUST + * have been initialized prior to using it in this macro. + * \param n another &struct list_head to use as temporary storage + * \param head the head for your list. + */ +#define list_for_remaining_safe(pos, n, head) \ + for (n = pos->next; pos != (head); pos = n, n = pos->next) + +static inline int +ldlm_same_flock_owner(struct ldlm_lock *lock, struct ldlm_lock *new) +{ + return((new->l_policy_data.l_flock.owner == + lock->l_policy_data.l_flock.owner) && + (new->l_export == lock->l_export)); +} + +static inline int +ldlm_flocks_overlap(struct ldlm_lock *lock, struct ldlm_lock *new) +{ + return((new->l_policy_data.l_flock.start <= + lock->l_policy_data.l_flock.end) && + (new->l_policy_data.l_flock.end >= + lock->l_policy_data.l_flock.start)); +} + +static inline int ldlm_flock_blocking_link(struct ldlm_lock *req, + struct ldlm_lock *lock) +{ + int rc = 0; + + /* For server only */ + if (req->l_export == NULL) + return 0; + + if (unlikely(req->l_export->exp_flock_hash == NULL)) { + rc = ldlm_init_flock_export(req->l_export); + if (rc) + goto error; + } + + LASSERT(hlist_unhashed(&req->l_exp_flock_hash)); + + req->l_policy_data.l_flock.blocking_owner = + lock->l_policy_data.l_flock.owner; + req->l_policy_data.l_flock.blocking_export = + lock->l_export; + req->l_policy_data.l_flock.blocking_refs = 0; + + cfs_hash_add(req->l_export->exp_flock_hash, + &req->l_policy_data.l_flock.owner, + &req->l_exp_flock_hash); +error: + return rc; +} + +static inline void ldlm_flock_blocking_unlink(struct ldlm_lock *req) +{ + /* For server only */ + if (req->l_export == NULL) + return; + + check_res_locked(req->l_resource); + if (req->l_export->exp_flock_hash != NULL && + !hlist_unhashed(&req->l_exp_flock_hash)) + cfs_hash_del(req->l_export->exp_flock_hash, + &req->l_policy_data.l_flock.owner, + &req->l_exp_flock_hash); +} + +static inline void +ldlm_flock_destroy(struct ldlm_lock *lock, ldlm_mode_t mode, __u64 flags) +{ + ENTRY; + + LDLM_DEBUG(lock, "ldlm_flock_destroy(mode: %d, flags: 0x%llx)", + mode, flags); + + /* Safe to not lock here, since it should be empty anyway */ + LASSERT(hlist_unhashed(&lock->l_exp_flock_hash)); + + list_del_init(&lock->l_res_link); + if (flags == LDLM_FL_WAIT_NOREPROC && + !(lock->l_flags & LDLM_FL_FAILED)) { + /* client side - set a flag to prevent sending a CANCEL */ + lock->l_flags |= LDLM_FL_LOCAL_ONLY | LDLM_FL_CBPENDING; + + /* when reaching here, it is under lock_res_and_lock(). Thus, + need call the nolock version of ldlm_lock_decref_internal*/ + ldlm_lock_decref_internal_nolock(lock, mode); + } + + ldlm_lock_destroy_nolock(lock); + EXIT; +} + +/** + * POSIX locks deadlock detection code. + * + * Given a new lock \a req and an existing lock \a bl_lock it conflicts + * with, we need to iterate through all blocked POSIX locks for this + * export and see if there is a deadlock condition arising. (i.e. when + * one client holds a lock on something and want a lock on something + * else and at the same time another client has the opposite situation). + */ +static int +ldlm_flock_deadlock(struct ldlm_lock *req, struct ldlm_lock *bl_lock) +{ + struct obd_export *req_exp = req->l_export; + struct obd_export *bl_exp = bl_lock->l_export; + __u64 req_owner = req->l_policy_data.l_flock.owner; + __u64 bl_owner = bl_lock->l_policy_data.l_flock.owner; + + /* For server only */ + if (req_exp == NULL) + return 0; + + class_export_get(bl_exp); + while (1) { + struct obd_export *bl_exp_new; + struct ldlm_lock *lock = NULL; + struct ldlm_flock *flock; + + if (bl_exp->exp_flock_hash != NULL) + lock = cfs_hash_lookup(bl_exp->exp_flock_hash, + &bl_owner); + if (lock == NULL) + break; + + flock = &lock->l_policy_data.l_flock; + LASSERT(flock->owner == bl_owner); + bl_owner = flock->blocking_owner; + bl_exp_new = class_export_get(flock->blocking_export); + class_export_put(bl_exp); + + cfs_hash_put(bl_exp->exp_flock_hash, &lock->l_exp_flock_hash); + bl_exp = bl_exp_new; + + if (bl_owner == req_owner && bl_exp == req_exp) { + class_export_put(bl_exp); + return 1; + } + } + class_export_put(bl_exp); + + return 0; +} + +/** + * Process a granting attempt for flock lock. + * Must be called under ns lock held. + * + * This function looks for any conflicts for \a lock in the granted or + * waiting queues. The lock is granted if no conflicts are found in + * either queue. + * + * It is also responsible for splitting a lock if a portion of the lock + * is released. + * + * If \a first_enq is 0 (ie, called from ldlm_reprocess_queue): + * - blocking ASTs have already been sent + * + * If \a first_enq is 1 (ie, called from ldlm_lock_enqueue): + * - blocking ASTs have not been sent yet, so list of conflicting locks + * would be collected and ASTs sent. + */ +int +ldlm_process_flock_lock(struct ldlm_lock *req, __u64 *flags, int first_enq, + ldlm_error_t *err, struct list_head *work_list) +{ + struct ldlm_resource *res = req->l_resource; + struct ldlm_namespace *ns = ldlm_res_to_ns(res); + struct list_head *tmp; + struct list_head *ownlocks = NULL; + struct ldlm_lock *lock = NULL; + struct ldlm_lock *new = req; + struct ldlm_lock *new2 = NULL; + ldlm_mode_t mode = req->l_req_mode; + int local = ns_is_client(ns); + int added = (mode == LCK_NL); + int overlaps = 0; + int splitted = 0; + const struct ldlm_callback_suite null_cbs = { NULL }; + int rc; + ENTRY; + + CDEBUG(D_DLMTRACE, "flags %#llx owner "LPU64" pid %u mode %u start " + LPU64" end "LPU64"\n", *flags, + new->l_policy_data.l_flock.owner, + new->l_policy_data.l_flock.pid, mode, + req->l_policy_data.l_flock.start, + req->l_policy_data.l_flock.end); + + *err = ELDLM_OK; + + if (local) { + /* No blocking ASTs are sent to the clients for + * Posix file & record locks */ + req->l_blocking_ast = NULL; + } else { + /* Called on the server for lock cancels. */ + req->l_blocking_ast = ldlm_flock_blocking_ast; + } + +reprocess: + if ((*flags == LDLM_FL_WAIT_NOREPROC) || (mode == LCK_NL)) { + /* This loop determines where this processes locks start + * in the resource lr_granted list. */ + 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 { + lockmode_verify(mode); + + /* This loop determines if there are existing locks + * that conflict with the new lock request. */ + 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 (!first_enq) + RETURN(LDLM_ITER_CONTINUE); + + if (*flags & LDLM_FL_BLOCK_NOWAIT) { + ldlm_flock_destroy(req, mode, *flags); + *err = -EAGAIN; + RETURN(LDLM_ITER_STOP); + } + + if (*flags & LDLM_FL_TEST_LOCK) { + ldlm_flock_destroy(req, mode, *flags); + req->l_req_mode = lock->l_granted_mode; + req->l_policy_data.l_flock.pid = + lock->l_policy_data.l_flock.pid; + req->l_policy_data.l_flock.start = + lock->l_policy_data.l_flock.start; + req->l_policy_data.l_flock.end = + lock->l_policy_data.l_flock.end; + *flags |= LDLM_FL_LOCK_CHANGED; + RETURN(LDLM_ITER_STOP); + } + + if (ldlm_flock_deadlock(req, lock)) { + ldlm_flock_destroy(req, mode, *flags); + *err = -EDEADLK; + RETURN(LDLM_ITER_STOP); + } + + rc = ldlm_flock_blocking_link(req, lock); + if (rc) { + ldlm_flock_destroy(req, mode, *flags); + *err = rc; + RETURN(LDLM_ITER_STOP); + } + ldlm_resource_add_lock(res, &res->lr_waiting, req); + *flags |= LDLM_FL_BLOCK_GRANTED; + RETURN(LDLM_ITER_STOP); + } + } + + if (*flags & LDLM_FL_TEST_LOCK) { + ldlm_flock_destroy(req, mode, *flags); + req->l_req_mode = LCK_NL; + *flags |= LDLM_FL_LOCK_CHANGED; + RETURN(LDLM_ITER_STOP); + } + + /* In case we had slept on this lock request take it off of the + * deadlock detection hash list. */ + ldlm_flock_blocking_unlink(req); + + /* Scan the locks owned by this process that overlap this request. + * We may have to merge or split existing locks. */ + + if (!ownlocks) + ownlocks = &res->lr_granted; + + list_for_remaining_safe(ownlocks, tmp, &res->lr_granted) { + 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 the modes are the same then we need to process + * locks that overlap OR adjoin the new lock. The extra + * logic condition is necessary to deal with arithmetic + * overflow and underflow. */ + if ((new->l_policy_data.l_flock.start > + (lock->l_policy_data.l_flock.end + 1)) + && (lock->l_policy_data.l_flock.end != + OBD_OBJECT_EOF)) + continue; + + if ((new->l_policy_data.l_flock.end < + (lock->l_policy_data.l_flock.start - 1)) + && (lock->l_policy_data.l_flock.start != 0)) + break; + + if (new->l_policy_data.l_flock.start < + lock->l_policy_data.l_flock.start) { + lock->l_policy_data.l_flock.start = + new->l_policy_data.l_flock.start; + } else { + new->l_policy_data.l_flock.start = + lock->l_policy_data.l_flock.start; + } + + if (new->l_policy_data.l_flock.end > + lock->l_policy_data.l_flock.end) { + lock->l_policy_data.l_flock.end = + new->l_policy_data.l_flock.end; + } else { + new->l_policy_data.l_flock.end = + lock->l_policy_data.l_flock.end; + } + + if (added) { + ldlm_flock_destroy(lock, mode, *flags); + } else { + new = lock; + added = 1; + } + continue; + } + + if (new->l_policy_data.l_flock.start > + lock->l_policy_data.l_flock.end) + continue; + + if (new->l_policy_data.l_flock.end < + lock->l_policy_data.l_flock.start) + break; + + ++overlaps; + + if (new->l_policy_data.l_flock.start <= + lock->l_policy_data.l_flock.start) { + if (new->l_policy_data.l_flock.end < + lock->l_policy_data.l_flock.end) { + lock->l_policy_data.l_flock.start = + new->l_policy_data.l_flock.end + 1; + break; + } + ldlm_flock_destroy(lock, lock->l_req_mode, *flags); + continue; + } + if (new->l_policy_data.l_flock.end >= + lock->l_policy_data.l_flock.end) { + lock->l_policy_data.l_flock.end = + new->l_policy_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 replays the lock request so + * it must see the original lock data in the reply. */ + + /* XXX - if ldlm_lock_new() can sleep we should + * release the lr_lock, allocate the new lock, + * and restart processing this lock. */ + if (!new2) { + unlock_res_and_lock(req); + new2 = ldlm_lock_create(ns, &res->lr_name, LDLM_FLOCK, + lock->l_granted_mode, &null_cbs, + NULL, 0, LVB_T_NONE); + lock_res_and_lock(req); + if (!new2) { + ldlm_flock_destroy(req, lock->l_granted_mode, + *flags); + *err = -ENOLCK; + RETURN(LDLM_ITER_STOP); + } + goto reprocess; + } + + splitted = 1; + + new2->l_granted_mode = lock->l_granted_mode; + new2->l_policy_data.l_flock.pid = + new->l_policy_data.l_flock.pid; + new2->l_policy_data.l_flock.owner = + new->l_policy_data.l_flock.owner; + new2->l_policy_data.l_flock.start = + lock->l_policy_data.l_flock.start; + new2->l_policy_data.l_flock.end = + new->l_policy_data.l_flock.start - 1; + lock->l_policy_data.l_flock.start = + new->l_policy_data.l_flock.end + 1; + new2->l_conn_export = lock->l_conn_export; + if (lock->l_export != NULL) { + new2->l_export = class_export_lock_get(lock->l_export, new2); + if (new2->l_export->exp_lock_hash && + hlist_unhashed(&new2->l_exp_hash)) + cfs_hash_add(new2->l_export->exp_lock_hash, + &new2->l_remote_handle, + &new2->l_exp_hash); + } + if (*flags == LDLM_FL_WAIT_NOREPROC) + ldlm_lock_addref_internal_nolock(new2, + lock->l_granted_mode); + + /* insert new2 at lock */ + ldlm_resource_add_lock(res, ownlocks, new2); + LDLM_LOCK_RELEASE(new2); + break; + } + + /* if new2 is created but never used, destroy it*/ + if (splitted == 0 && new2 != NULL) + ldlm_lock_destroy_nolock(new2); + + /* At this point we're granting the lock request. */ + req->l_granted_mode = req->l_req_mode; + + /* Add req to the granted queue before calling ldlm_reprocess_all(). */ + if (!added) { + list_del_init(&req->l_res_link); + /* insert new lock before ownlocks in list. */ + ldlm_resource_add_lock(res, ownlocks, req); + } + + if (*flags != LDLM_FL_WAIT_NOREPROC) { + /* The only one possible case for client-side calls flock + * policy function is ldlm_flock_completion_ast inside which + * carries LDLM_FL_WAIT_NOREPROC flag. */ + CERROR("Illegal parameter for client-side-only module.\n"); + LBUG(); + } + + /* In case we're reprocessing the requested lock we can't destroy + * it until after calling ldlm_add_ast_work_item() above so that laawi() + * can bump the reference count on \a req. Otherwise \a req + * could be freed before the completion AST can be sent. */ + if (added) + ldlm_flock_destroy(req, mode, *flags); + + ldlm_resource_dump(D_INFO, res); + RETURN(LDLM_ITER_CONTINUE); +} + +struct ldlm_flock_wait_data { + struct ldlm_lock *fwd_lock; + int fwd_generation; +}; + +static void +ldlm_flock_interrupted_wait(void *data) +{ + struct ldlm_lock *lock; + ENTRY; + + lock = ((struct ldlm_flock_wait_data *)data)->fwd_lock; + + /* take lock off the deadlock detection hash list. */ + lock_res_and_lock(lock); + ldlm_flock_blocking_unlink(lock); + + /* client side - set flag to prevent lock from being put on LRU list */ + lock->l_flags |= LDLM_FL_CBPENDING; + unlock_res_and_lock(lock); + + EXIT; +} + +/** + * Flock completion callback function. + * + * \param lock [in,out]: A lock to be handled + * \param flags [in]: flags + * \param *data [in]: ldlm_work_cp_ast_lock() will use ldlm_cb_set_arg + * + * \retval 0 : success + * \retval <0 : failure + */ +int +ldlm_flock_completion_ast(struct ldlm_lock *lock, __u64 flags, void *data) +{ + struct file_lock *getlk = lock->l_ast_data; + struct obd_device *obd; + struct obd_import *imp = NULL; + struct ldlm_flock_wait_data fwd; + struct l_wait_info lwi; + ldlm_error_t err; + int rc = 0; + ENTRY; + + CDEBUG(D_DLMTRACE, "flags: 0x%llx data: %p getlk: %p\n", + flags, data, getlk); + + /* Import invalidation. We need to actually release the lock + * references being held, so that it can go away. No point in + * holding the lock even if app still believes it has it, since + * server already dropped it anyway. Only for granted locks too. */ + if ((lock->l_flags & (LDLM_FL_FAILED|LDLM_FL_LOCAL_ONLY)) == + (LDLM_FL_FAILED|LDLM_FL_LOCAL_ONLY)) { + if (lock->l_req_mode == lock->l_granted_mode && + lock->l_granted_mode != LCK_NL && + NULL == data) + ldlm_lock_decref_internal(lock, lock->l_req_mode); + + /* Need to wake up the waiter if we were evicted */ + wake_up(&lock->l_waitq); + RETURN(0); + } + + LASSERT(flags != LDLM_FL_WAIT_NOREPROC); + + if (!(flags & (LDLM_FL_BLOCK_WAIT | LDLM_FL_BLOCK_GRANTED | + LDLM_FL_BLOCK_CONV))) { + if (NULL == data) + /* mds granted the lock in the reply */ + goto granted; + /* CP AST RPC: lock get granted, wake it up */ + wake_up(&lock->l_waitq); + RETURN(0); + } + + LDLM_DEBUG(lock, "client-side enqueue returned a blocked lock, " + "sleeping"); + fwd.fwd_lock = lock; + obd = class_exp2obd(lock->l_conn_export); + + /* if this is a local lock, there is no import */ + if (NULL != obd) + imp = obd->u.cli.cl_import; + + if (NULL != imp) { + spin_lock(&imp->imp_lock); + fwd.fwd_generation = imp->imp_generation; + spin_unlock(&imp->imp_lock); + } + + lwi = LWI_TIMEOUT_INTR(0, NULL, ldlm_flock_interrupted_wait, &fwd); + + /* Go to sleep until the lock is granted. */ + rc = l_wait_event(lock->l_waitq, is_granted_or_cancelled(lock), &lwi); + + if (rc) { + LDLM_DEBUG(lock, "client-side enqueue waking up: failed (%d)", + rc); + RETURN(rc); + } + +granted: + OBD_FAIL_TIMEOUT(OBD_FAIL_LDLM_CP_CB_WAIT, 10); + + if (lock->l_destroyed) { + LDLM_DEBUG(lock, "client-side enqueue waking up: destroyed"); + RETURN(0); + } + + if (lock->l_flags & LDLM_FL_FAILED) { + LDLM_DEBUG(lock, "client-side enqueue waking up: failed"); + RETURN(-EIO); + } + + if (rc) { + LDLM_DEBUG(lock, "client-side enqueue waking up: failed (%d)", + rc); + RETURN(rc); + } + + LDLM_DEBUG(lock, "client-side enqueue granted"); + + lock_res_and_lock(lock); + + /* take lock off the deadlock detection hash list. */ + ldlm_flock_blocking_unlink(lock); + + /* ldlm_lock_enqueue() has already placed lock on the granted list. */ + list_del_init(&lock->l_res_link); + + if (flags & LDLM_FL_TEST_LOCK) { + /* fcntl(F_GETLK) request */ + /* The old mode was saved in getlk->fl_type so that if the mode + * in the lock changes we can decref the appropriate refcount.*/ + ldlm_flock_destroy(lock, flock_type(getlk), + LDLM_FL_WAIT_NOREPROC); + switch (lock->l_granted_mode) { + case LCK_PR: + flock_set_type(getlk, F_RDLCK); + break; + case LCK_PW: + flock_set_type(getlk, F_WRLCK); + break; + default: + flock_set_type(getlk, F_UNLCK); + } + flock_set_pid(getlk, (pid_t)lock->l_policy_data.l_flock.pid); + flock_set_start(getlk, + (loff_t)lock->l_policy_data.l_flock.start); + flock_set_end(getlk, + (loff_t)lock->l_policy_data.l_flock.end); + } else { + __u64 noreproc = LDLM_FL_WAIT_NOREPROC; + + /* We need to reprocess the lock to do merges or splits + * with existing locks owned by this process. */ + ldlm_process_flock_lock(lock, &noreproc, 1, &err, NULL); + } + unlock_res_and_lock(lock); + RETURN(0); +} +EXPORT_SYMBOL(ldlm_flock_completion_ast); + +int ldlm_flock_blocking_ast(struct ldlm_lock *lock, struct ldlm_lock_desc *desc, + void *data, int flag) +{ + ENTRY; + + LASSERT(lock); + LASSERT(flag == LDLM_CB_CANCELING); + + /* take lock off the deadlock detection hash list. */ + lock_res_and_lock(lock); + ldlm_flock_blocking_unlink(lock); + unlock_res_and_lock(lock); + RETURN(0); +} + +void ldlm_flock_policy_wire18_to_local(const ldlm_wire_policy_data_t *wpolicy, + ldlm_policy_data_t *lpolicy) +{ + memset(lpolicy, 0, sizeof(*lpolicy)); + lpolicy->l_flock.start = wpolicy->l_flock.lfw_start; + lpolicy->l_flock.end = wpolicy->l_flock.lfw_end; + lpolicy->l_flock.pid = wpolicy->l_flock.lfw_pid; + /* Compat code, old clients had no idea about owner field and + * relied solely on pid for ownership. Introduced in LU-104, 2.1, + * April 2011 */ + lpolicy->l_flock.owner = wpolicy->l_flock.lfw_pid; +} + + +void ldlm_flock_policy_wire21_to_local(const ldlm_wire_policy_data_t *wpolicy, + ldlm_policy_data_t *lpolicy) +{ + memset(lpolicy, 0, sizeof(*lpolicy)); + lpolicy->l_flock.start = wpolicy->l_flock.lfw_start; + lpolicy->l_flock.end = wpolicy->l_flock.lfw_end; + lpolicy->l_flock.pid = wpolicy->l_flock.lfw_pid; + lpolicy->l_flock.owner = wpolicy->l_flock.lfw_owner; +} + +void ldlm_flock_policy_local_to_wire(const ldlm_policy_data_t *lpolicy, + ldlm_wire_policy_data_t *wpolicy) +{ + memset(wpolicy, 0, sizeof(*wpolicy)); + wpolicy->l_flock.lfw_start = lpolicy->l_flock.start; + wpolicy->l_flock.lfw_end = lpolicy->l_flock.end; + wpolicy->l_flock.lfw_pid = lpolicy->l_flock.pid; + wpolicy->l_flock.lfw_owner = lpolicy->l_flock.owner; +} + +/* + * Export handle<->flock hash operations. + */ +static unsigned +ldlm_export_flock_hash(cfs_hash_t *hs, const void *key, unsigned mask) +{ + return cfs_hash_u64_hash(*(__u64 *)key, mask); +} + +static void * +ldlm_export_flock_key(struct hlist_node *hnode) +{ + struct ldlm_lock *lock; + + lock = hlist_entry(hnode, struct ldlm_lock, l_exp_flock_hash); + return &lock->l_policy_data.l_flock.owner; +} + +static int +ldlm_export_flock_keycmp(const void *key, struct hlist_node *hnode) +{ + return !memcmp(ldlm_export_flock_key(hnode), key, sizeof(__u64)); +} + +static void * +ldlm_export_flock_object(struct hlist_node *hnode) +{ + return hlist_entry(hnode, struct ldlm_lock, l_exp_flock_hash); +} + +static void +ldlm_export_flock_get(cfs_hash_t *hs, struct hlist_node *hnode) +{ + struct ldlm_lock *lock; + struct ldlm_flock *flock; + + lock = hlist_entry(hnode, struct ldlm_lock, l_exp_flock_hash); + LDLM_LOCK_GET(lock); + + flock = &lock->l_policy_data.l_flock; + LASSERT(flock->blocking_export != NULL); + class_export_get(flock->blocking_export); + flock->blocking_refs++; +} + +static void +ldlm_export_flock_put(cfs_hash_t *hs, struct hlist_node *hnode) +{ + struct ldlm_lock *lock; + struct ldlm_flock *flock; + + lock = hlist_entry(hnode, struct ldlm_lock, l_exp_flock_hash); + LDLM_LOCK_RELEASE(lock); + + flock = &lock->l_policy_data.l_flock; + LASSERT(flock->blocking_export != NULL); + class_export_put(flock->blocking_export); + if (--flock->blocking_refs == 0) { + flock->blocking_owner = 0; + flock->blocking_export = NULL; + } +} + +static cfs_hash_ops_t ldlm_export_flock_ops = { + .hs_hash = ldlm_export_flock_hash, + .hs_key = ldlm_export_flock_key, + .hs_keycmp = ldlm_export_flock_keycmp, + .hs_object = ldlm_export_flock_object, + .hs_get = ldlm_export_flock_get, + .hs_put = ldlm_export_flock_put, + .hs_put_locked = ldlm_export_flock_put, +}; + +int ldlm_init_flock_export(struct obd_export *exp) +{ + exp->exp_flock_hash = + cfs_hash_create(obd_uuid2str(&exp->exp_client_uuid), + HASH_EXP_LOCK_CUR_BITS, + HASH_EXP_LOCK_MAX_BITS, + HASH_EXP_LOCK_BKT_BITS, 0, + CFS_HASH_MIN_THETA, CFS_HASH_MAX_THETA, + &ldlm_export_flock_ops, + CFS_HASH_DEFAULT | CFS_HASH_NBLK_CHANGE); + if (!exp->exp_flock_hash) + RETURN(-ENOMEM); + + RETURN(0); +} +EXPORT_SYMBOL(ldlm_init_flock_export); + +void ldlm_destroy_flock_export(struct obd_export *exp) +{ + ENTRY; + if (exp->exp_flock_hash) { + cfs_hash_putref(exp->exp_flock_hash); + exp->exp_flock_hash = NULL; + } + EXIT; +} +EXPORT_SYMBOL(ldlm_destroy_flock_export); |