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* 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)
{
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);
}
/**
* 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;
LASSERT(req != lock);
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;
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;
}
/* add lock to blocking list before deadlock
* check to prevent race */
rc = ldlm_flock_blocking_link(req, lock);
if (rc) {
ldlm_flock_destroy(req, mode, *flags);
*err = rc;
return LDLM_ITER_STOP;
}
if (ldlm_flock_deadlock(req, lock)) {
ldlm_flock_blocking_unlink(req);
ldlm_flock_destroy(req, mode, *flags);
*err = -EDEADLK;
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;
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);
}
/**
* 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;
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_flags & LDLM_FL_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)
{
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)
{
if (exp->exp_flock_hash) {
cfs_hash_putref(exp->exp_flock_hash);
exp->exp_flock_hash = NULL;
}
}
EXPORT_SYMBOL(ldlm_destroy_flock_export);
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