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nest-open-source / nest-learning-thermostat / 5.7.1 / linux-imx-ul / refs/heads/master / . / drivers / staging / lustre / lustre / ldlm / ldlm_request.c
blob: 4f713183145bb823a955a51b4dff94cb8ba17cbb [file] [log] [blame]
/*
* 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) 2002, 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 contains Asynchronous System Trap (AST) handlers and related
* LDLM request-processing routines.
*
* An AST is a callback issued on a lock when its state is changed. There are
* several different types of ASTs (callbacks) registered for each lock:
*
* - completion AST: when a lock is enqueued by some process, but cannot be
* granted immediately due to other conflicting locks on the same resource,
* the completion AST is sent to notify the caller when the lock is
* eventually granted
*
* - blocking AST: when a lock is granted to some process, if another process
* enqueues a conflicting (blocking) lock on a resource, a blocking AST is
* sent to notify the holder(s) of the lock(s) of the conflicting lock
* request. The lock holder(s) must release their lock(s) on that resource in
* a timely manner or be evicted by the server.
*
* - glimpse AST: this is used when a process wants information about a lock
* (i.e. the lock value block (LVB)) but does not necessarily require holding
* the lock. If the resource is locked, the lock holder(s) are sent glimpse
* ASTs and the LVB is returned to the caller, and lock holder(s) may CANCEL
* their lock(s) if they are idle. If the resource is not locked, the server
* may grant the lock.
*/
#define DEBUG_SUBSYSTEM S_LDLM
#include "../include/lustre_dlm.h"
#include "../include/obd_class.h"
#include "../include/obd.h"
#include "ldlm_internal.h"
int ldlm_enqueue_min = OBD_TIMEOUT_DEFAULT;
module_param(ldlm_enqueue_min, int, 0644);
MODULE_PARM_DESC(ldlm_enqueue_min, "lock enqueue timeout minimum");
/* in client side, whether the cached locks will be canceled before replay */
unsigned int ldlm_cancel_unused_locks_before_replay = 1;
static void interrupted_completion_wait(void *data)
{
}
struct lock_wait_data {
struct ldlm_lock *lwd_lock;
__u32 lwd_conn_cnt;
};
struct ldlm_async_args {
struct lustre_handle lock_handle;
};
int ldlm_expired_completion_wait(void *data)
{
struct lock_wait_data *lwd = data;
struct ldlm_lock *lock = lwd->lwd_lock;
struct obd_import *imp;
struct obd_device *obd;
if (lock->l_conn_export == NULL) {
static unsigned long next_dump, last_dump;
LCONSOLE_WARN("lock timed out (enqueued at "CFS_TIME_T", "
CFS_DURATION_T"s ago)\n",
lock->l_last_activity,
cfs_time_sub(get_seconds(),
lock->l_last_activity));
LDLM_DEBUG(lock, "lock timed out (enqueued at " CFS_TIME_T ", " CFS_DURATION_T "s ago); not entering recovery in server code, just going back to sleep",
lock->l_last_activity,
cfs_time_sub(get_seconds(),
lock->l_last_activity));
if (cfs_time_after(cfs_time_current(), next_dump)) {
last_dump = next_dump;
next_dump = cfs_time_shift(300);
ldlm_namespace_dump(D_DLMTRACE,
ldlm_lock_to_ns(lock));
if (last_dump == 0)
libcfs_debug_dumplog();
}
return 0;
}
obd = lock->l_conn_export->exp_obd;
imp = obd->u.cli.cl_import;
ptlrpc_fail_import(imp, lwd->lwd_conn_cnt);
LDLM_ERROR(lock, "lock timed out (enqueued at "CFS_TIME_T", "
CFS_DURATION_T"s ago), entering recovery for %s@%s",
lock->l_last_activity,
cfs_time_sub(get_seconds(), lock->l_last_activity),
obd2cli_tgt(obd), imp->imp_connection->c_remote_uuid.uuid);
return 0;
}
EXPORT_SYMBOL(ldlm_expired_completion_wait);
/* We use the same basis for both server side and client side functions
from a single node. */
int ldlm_get_enq_timeout(struct ldlm_lock *lock)
{
int timeout = at_get(ldlm_lock_to_ns_at(lock));
if (AT_OFF)
return obd_timeout / 2;
/* Since these are non-updating timeouts, we should be conservative.
It would be nice to have some kind of "early reply" mechanism for
lock callbacks too... */
timeout = min_t(int, at_max, timeout + (timeout >> 1)); /* 150% */
return max(timeout, ldlm_enqueue_min);
}
EXPORT_SYMBOL(ldlm_get_enq_timeout);
/**
* Helper function for ldlm_completion_ast(), updating timings when lock is
* actually granted.
*/
static int ldlm_completion_tail(struct ldlm_lock *lock)
{
long delay;
int result;
if (lock->l_flags & (LDLM_FL_DESTROYED | LDLM_FL_FAILED)) {
LDLM_DEBUG(lock, "client-side enqueue: destroyed");
result = -EIO;
} else {
delay = cfs_time_sub(get_seconds(),
lock->l_last_activity);
LDLM_DEBUG(lock, "client-side enqueue: granted after "
CFS_DURATION_T"s", delay);
/* Update our time estimate */
at_measured(ldlm_lock_to_ns_at(lock),
delay);
result = 0;
}
return result;
}
/**
* Implementation of ->l_completion_ast() for a client, that doesn't wait
* until lock is granted. Suitable for locks enqueued through ptlrpcd, of
* other threads that cannot block for long.
*/
int ldlm_completion_ast_async(struct ldlm_lock *lock, __u64 flags, void *data)
{
if (flags == LDLM_FL_WAIT_NOREPROC) {
LDLM_DEBUG(lock, "client-side enqueue waiting on pending lock");
return 0;
}
if (!(flags & (LDLM_FL_BLOCK_WAIT | LDLM_FL_BLOCK_GRANTED |
LDLM_FL_BLOCK_CONV))) {
wake_up(&lock->l_waitq);
return ldlm_completion_tail(lock);
}
LDLM_DEBUG(lock, "client-side enqueue returned a blocked lock, going forward");
ldlm_reprocess_all(lock->l_resource);
return 0;
}
EXPORT_SYMBOL(ldlm_completion_ast_async);
/**
* Generic LDLM "completion" AST. This is called in several cases:
*
* - when a reply to an ENQUEUE RPC is received from the server
* (ldlm_cli_enqueue_fini()). Lock might be granted or not granted at
* this point (determined by flags);
*
* - when LDLM_CP_CALLBACK RPC comes to client to notify it that lock has
* been granted;
*
* - when ldlm_lock_match(LDLM_FL_LVB_READY) is about to wait until lock
* gets correct lvb;
*
* - to force all locks when resource is destroyed (cleanup_resource());
*
* - during lock conversion (not used currently).
*
* If lock is not granted in the first case, this function waits until second
* or penultimate cases happen in some other thread.
*
*/
int ldlm_completion_ast(struct ldlm_lock *lock, __u64 flags, void *data)
{
/* XXX ALLOCATE - 160 bytes */
struct lock_wait_data lwd;
struct obd_device *obd;
struct obd_import *imp = NULL;
struct l_wait_info lwi;
__u32 timeout;
int rc = 0;
if (flags == LDLM_FL_WAIT_NOREPROC) {
LDLM_DEBUG(lock, "client-side enqueue waiting on pending lock");
goto noreproc;
}
if (!(flags & (LDLM_FL_BLOCK_WAIT | LDLM_FL_BLOCK_GRANTED |
LDLM_FL_BLOCK_CONV))) {
wake_up(&lock->l_waitq);
return 0;
}
LDLM_DEBUG(lock, "client-side enqueue returned a blocked lock, sleeping");
noreproc:
obd = class_exp2obd(lock->l_conn_export);
/* if this is a local lock, then there is no import */
if (obd != NULL)
imp = obd->u.cli.cl_import;
/* Wait a long time for enqueue - server may have to callback a
lock from another client. Server will evict the other client if it
doesn't respond reasonably, and then give us the lock. */
timeout = ldlm_get_enq_timeout(lock) * 2;
lwd.lwd_lock = lock;
if (lock->l_flags & LDLM_FL_NO_TIMEOUT) {
LDLM_DEBUG(lock, "waiting indefinitely because of NO_TIMEOUT");
lwi = LWI_INTR(interrupted_completion_wait, &lwd);
} else {
lwi = LWI_TIMEOUT_INTR(cfs_time_seconds(timeout),
ldlm_expired_completion_wait,
interrupted_completion_wait, &lwd);
}
if (imp != NULL) {
spin_lock(&imp->imp_lock);
lwd.lwd_conn_cnt = imp->imp_conn_cnt;
spin_unlock(&imp->imp_lock);
}
if (ns_is_client(ldlm_lock_to_ns(lock)) &&
OBD_FAIL_CHECK_RESET(OBD_FAIL_LDLM_INTR_CP_AST,
OBD_FAIL_LDLM_CP_BL_RACE | OBD_FAIL_ONCE)) {
lock->l_flags |= LDLM_FL_FAIL_LOC;
rc = -EINTR;
} else {
/* Go to sleep until the lock is granted or cancelled. */
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;
}
return ldlm_completion_tail(lock);
}
EXPORT_SYMBOL(ldlm_completion_ast);
/**
* A helper to build a blocking AST function
*
* Perform a common operation for blocking ASTs:
* deferred lock cancellation.
*
* \param lock the lock blocking or canceling AST was called on
* \retval 0
* \see mdt_blocking_ast
* \see ldlm_blocking_ast
*/
int ldlm_blocking_ast_nocheck(struct ldlm_lock *lock)
{
int do_ast;
lock->l_flags |= LDLM_FL_CBPENDING;
do_ast = !lock->l_readers && !lock->l_writers;
unlock_res_and_lock(lock);
if (do_ast) {
struct lustre_handle lockh;
int rc;
LDLM_DEBUG(lock, "already unused, calling ldlm_cli_cancel");
ldlm_lock2handle(lock, &lockh);
rc = ldlm_cli_cancel(&lockh, LCF_ASYNC);
if (rc < 0)
CERROR("ldlm_cli_cancel: %d\n", rc);
} else {
LDLM_DEBUG(lock, "Lock still has references, will be cancelled later");
}
return 0;
}
EXPORT_SYMBOL(ldlm_blocking_ast_nocheck);
/**
* Server blocking AST
*
* ->l_blocking_ast() callback for LDLM locks acquired by server-side
* OBDs.
*
* \param lock the lock which blocks a request or cancelling lock
* \param desc unused
* \param data unused
* \param flag indicates whether this cancelling or blocking callback
* \retval 0
* \see ldlm_blocking_ast_nocheck
*/
int ldlm_blocking_ast(struct ldlm_lock *lock, struct ldlm_lock_desc *desc,
void *data, int flag)
{
if (flag == LDLM_CB_CANCELING) {
/* Don't need to do anything here. */
return 0;
}
lock_res_and_lock(lock);
/* Get this: if ldlm_blocking_ast is racing with intent_policy, such
* that ldlm_blocking_ast is called just before intent_policy method
* takes the lr_lock, then by the time we get the lock, we might not
* be the correct blocking function anymore. So check, and return
* early, if so. */
if (lock->l_blocking_ast != ldlm_blocking_ast) {
unlock_res_and_lock(lock);
return 0;
}
return ldlm_blocking_ast_nocheck(lock);
}
EXPORT_SYMBOL(ldlm_blocking_ast);
/**
* ->l_glimpse_ast() for DLM extent locks acquired on the server-side. See
* comment in filter_intent_policy() on why you may need this.
*/
int ldlm_glimpse_ast(struct ldlm_lock *lock, void *reqp)
{
/*
* Returning -ELDLM_NO_LOCK_DATA actually works, but the reason for
* that is rather subtle: with OST-side locking, it may so happen that
* _all_ extent locks are held by the OST. If client wants to obtain
* current file size it calls ll{,u}_glimpse_size(), and (as locks are
* on the server), dummy glimpse callback fires and does
* nothing. Client still receives correct file size due to the
* following fragment in filter_intent_policy():
*
* rc = l->l_glimpse_ast(l, NULL); // this will update the LVB
* if (rc != 0 && res->lr_namespace->ns_lvbo &&
* res->lr_namespace->ns_lvbo->lvbo_update) {
* res->lr_namespace->ns_lvbo->lvbo_update(res, NULL, 0, 1);
* }
*
* that is, after glimpse_ast() fails, filter_lvbo_update() runs, and
* returns correct file size to the client.
*/
return -ELDLM_NO_LOCK_DATA;
}
EXPORT_SYMBOL(ldlm_glimpse_ast);
/**
* Enqueue a local lock (typically on a server).
*/
int ldlm_cli_enqueue_local(struct ldlm_namespace *ns,
const struct ldlm_res_id *res_id,
ldlm_type_t type, ldlm_policy_data_t *policy,
ldlm_mode_t mode, __u64 *flags,
ldlm_blocking_callback blocking,
ldlm_completion_callback completion,
ldlm_glimpse_callback glimpse,
void *data, __u32 lvb_len, enum lvb_type lvb_type,
const __u64 *client_cookie,
struct lustre_handle *lockh)
{
struct ldlm_lock *lock;
int err;
const struct ldlm_callback_suite cbs = { .lcs_completion = completion,
.lcs_blocking = blocking,
.lcs_glimpse = glimpse,
};
LASSERT(!(*flags & LDLM_FL_REPLAY));
if (unlikely(ns_is_client(ns))) {
CERROR("Trying to enqueue local lock in a shadow namespace\n");
LBUG();
}
lock = ldlm_lock_create(ns, res_id, type, mode, &cbs, data, lvb_len,
lvb_type);
if (unlikely(!lock)) {
err = -ENOMEM;
goto out_nolock;
}
ldlm_lock2handle(lock, lockh);
/* NB: we don't have any lock now (lock_res_and_lock)
* because it's a new lock */
ldlm_lock_addref_internal_nolock(lock, mode);
lock->l_flags |= LDLM_FL_LOCAL;
if (*flags & LDLM_FL_ATOMIC_CB)
lock->l_flags |= LDLM_FL_ATOMIC_CB;
if (policy != NULL)
lock->l_policy_data = *policy;
if (client_cookie != NULL)
lock->l_client_cookie = *client_cookie;
if (type == LDLM_EXTENT)
lock->l_req_extent = policy->l_extent;
err = ldlm_lock_enqueue(ns, &lock, policy, flags);
if (unlikely(err != ELDLM_OK))
goto out;
if (policy != NULL)
*policy = lock->l_policy_data;
if (lock->l_completion_ast)
lock->l_completion_ast(lock, *flags, NULL);
LDLM_DEBUG(lock, "client-side local enqueue handler, new lock created");
out:
LDLM_LOCK_RELEASE(lock);
out_nolock:
return err;
}
EXPORT_SYMBOL(ldlm_cli_enqueue_local);
static void failed_lock_cleanup(struct ldlm_namespace *ns,
struct ldlm_lock *lock, int mode)
{
int need_cancel = 0;
/* Set a flag to prevent us from sending a CANCEL (bug 407) */
lock_res_and_lock(lock);
/* Check that lock is not granted or failed, we might race. */
if ((lock->l_req_mode != lock->l_granted_mode) &&
!(lock->l_flags & LDLM_FL_FAILED)) {
/* Make sure that this lock will not be found by raced
* bl_ast and -EINVAL reply is sent to server anyways.
* bug 17645 */
lock->l_flags |= LDLM_FL_LOCAL_ONLY | LDLM_FL_FAILED |
LDLM_FL_ATOMIC_CB | LDLM_FL_CBPENDING;
need_cancel = 1;
}
unlock_res_and_lock(lock);
if (need_cancel)
LDLM_DEBUG(lock,
"setting FL_LOCAL_ONLY | LDLM_FL_FAILED | LDLM_FL_ATOMIC_CB | LDLM_FL_CBPENDING");
else
LDLM_DEBUG(lock, "lock was granted or failed in race");
ldlm_lock_decref_internal(lock, mode);
/* XXX - HACK because we shouldn't call ldlm_lock_destroy()
* from llite/file.c/ll_file_flock(). */
/* This code makes for the fact that we do not have blocking handler on
* a client for flock locks. As such this is the place where we must
* completely kill failed locks. (interrupted and those that
* were waiting to be granted when server evicted us. */
if (lock->l_resource->lr_type == LDLM_FLOCK) {
lock_res_and_lock(lock);
ldlm_resource_unlink_lock(lock);
ldlm_lock_destroy_nolock(lock);
unlock_res_and_lock(lock);
}
}
/**
* Finishing portion of client lock enqueue code.
*
* Called after receiving reply from server.
*/
int ldlm_cli_enqueue_fini(struct obd_export *exp, struct ptlrpc_request *req,
ldlm_type_t type, __u8 with_policy, ldlm_mode_t mode,
__u64 *flags, void *lvb, __u32 lvb_len,
struct lustre_handle *lockh, int rc)
{
struct ldlm_namespace *ns = exp->exp_obd->obd_namespace;
int is_replay = *flags & LDLM_FL_REPLAY;
struct ldlm_lock *lock;
struct ldlm_reply *reply;
int cleanup_phase = 1;
int size = 0;
lock = ldlm_handle2lock(lockh);
/* ldlm_cli_enqueue is holding a reference on this lock. */
if (!lock) {
LASSERT(type == LDLM_FLOCK);
return -ENOLCK;
}
LASSERTF(ergo(lvb_len != 0, lvb_len == lock->l_lvb_len),
"lvb_len = %d, l_lvb_len = %d\n", lvb_len, lock->l_lvb_len);
if (rc != ELDLM_OK) {
LASSERT(!is_replay);
LDLM_DEBUG(lock, "client-side enqueue END (%s)",
rc == ELDLM_LOCK_ABORTED ? "ABORTED" : "FAILED");
if (rc != ELDLM_LOCK_ABORTED)
goto cleanup;
}
/* Before we return, swab the reply */
reply = req_capsule_server_get(&req->rq_pill, &RMF_DLM_REP);
if (reply == NULL) {
rc = -EPROTO;
goto cleanup;
}
if (lvb_len != 0) {
LASSERT(lvb != NULL);
size = req_capsule_get_size(&req->rq_pill, &RMF_DLM_LVB,
RCL_SERVER);
if (size < 0) {
LDLM_ERROR(lock, "Fail to get lvb_len, rc = %d", size);
rc = size;
goto cleanup;
} else if (unlikely(size > lvb_len)) {
LDLM_ERROR(lock, "Replied LVB is larger than expectation, expected = %d, replied = %d",
lvb_len, size);
rc = -EINVAL;
goto cleanup;
}
}
if (rc == ELDLM_LOCK_ABORTED) {
if (lvb_len != 0)
rc = ldlm_fill_lvb(lock, &req->rq_pill, RCL_SERVER,
lvb, size);
if (rc == 0)
rc = ELDLM_LOCK_ABORTED;
goto cleanup;
}
/* lock enqueued on the server */
cleanup_phase = 0;
lock_res_and_lock(lock);
/* Key change rehash lock in per-export hash with new key */
if (exp->exp_lock_hash) {
/* In the function below, .hs_keycmp resolves to
* ldlm_export_lock_keycmp() */
/* coverity[overrun-buffer-val] */
cfs_hash_rehash_key(exp->exp_lock_hash,
&lock->l_remote_handle,
&reply->lock_handle,
&lock->l_exp_hash);
} else {
lock->l_remote_handle = reply->lock_handle;
}
*flags = ldlm_flags_from_wire(reply->lock_flags);
lock->l_flags |= ldlm_flags_from_wire(reply->lock_flags &
LDLM_INHERIT_FLAGS);
/* move NO_TIMEOUT flag to the lock to force ldlm_lock_match()
* to wait with no timeout as well */
lock->l_flags |= ldlm_flags_from_wire(reply->lock_flags &
LDLM_FL_NO_TIMEOUT);
unlock_res_and_lock(lock);
CDEBUG(D_INFO, "local: %p, remote cookie: %#llx, flags: 0x%llx\n",
lock, reply->lock_handle.cookie, *flags);
/* If enqueue returned a blocked lock but the completion handler has
* already run, then it fixed up the resource and we don't need to do it
* again. */
if ((*flags) & LDLM_FL_LOCK_CHANGED) {
int newmode = reply->lock_desc.l_req_mode;
LASSERT(!is_replay);
if (newmode && newmode != lock->l_req_mode) {
LDLM_DEBUG(lock, "server returned different mode %s",
ldlm_lockname[newmode]);
lock->l_req_mode = newmode;
}
if (!ldlm_res_eq(&reply->lock_desc.l_resource.lr_name,
&lock->l_resource->lr_name)) {
CDEBUG(D_INFO, "remote intent success, locking "DLDLMRES
" instead of "DLDLMRES"\n",
PLDLMRES(&reply->lock_desc.l_resource),
PLDLMRES(lock->l_resource));
rc = ldlm_lock_change_resource(ns, lock,
&reply->lock_desc.l_resource.lr_name);
if (rc || lock->l_resource == NULL) {
rc = -ENOMEM;
goto cleanup;
}
LDLM_DEBUG(lock, "client-side enqueue, new resource");
}
if (with_policy)
if (!(type == LDLM_IBITS &&
!(exp_connect_flags(exp) & OBD_CONNECT_IBITS)))
/* We assume lock type cannot change on server*/
ldlm_convert_policy_to_local(exp,
lock->l_resource->lr_type,
&reply->lock_desc.l_policy_data,
&lock->l_policy_data);
if (type != LDLM_PLAIN)
LDLM_DEBUG(lock,
"client-side enqueue, new policy data");
}
if ((*flags) & LDLM_FL_AST_SENT ||
/* Cancel extent locks as soon as possible on a liblustre client,
* because it cannot handle asynchronous ASTs robustly (see
* bug 7311). */
(LIBLUSTRE_CLIENT && type == LDLM_EXTENT)) {
lock_res_and_lock(lock);
lock->l_flags |= LDLM_FL_CBPENDING | LDLM_FL_BL_AST;
unlock_res_and_lock(lock);
LDLM_DEBUG(lock, "enqueue reply includes blocking AST");
}
/* If the lock has already been granted by a completion AST, don't
* clobber the LVB with an older one. */
if (lvb_len != 0) {
/* We must lock or a racing completion might update lvb without
* letting us know and we'll clobber the correct value.
* Cannot unlock after the check either, a that still leaves
* a tiny window for completion to get in */
lock_res_and_lock(lock);
if (lock->l_req_mode != lock->l_granted_mode)
rc = ldlm_fill_lvb(lock, &req->rq_pill, RCL_SERVER,
lock->l_lvb_data, size);
unlock_res_and_lock(lock);
if (rc < 0) {
cleanup_phase = 1;
goto cleanup;
}
}
if (!is_replay) {
rc = ldlm_lock_enqueue(ns, &lock, NULL, flags);
if (lock->l_completion_ast != NULL) {
int err = lock->l_completion_ast(lock, *flags, NULL);
if (!rc)
rc = err;
if (rc)
cleanup_phase = 1;
}
}
if (lvb_len && lvb != NULL) {
/* Copy the LVB here, and not earlier, because the completion
* AST (if any) can override what we got in the reply */
memcpy(lvb, lock->l_lvb_data, lvb_len);
}
LDLM_DEBUG(lock, "client-side enqueue END");
cleanup:
if (cleanup_phase == 1 && rc)
failed_lock_cleanup(ns, lock, mode);
/* Put lock 2 times, the second reference is held by ldlm_cli_enqueue */
LDLM_LOCK_PUT(lock);
LDLM_LOCK_RELEASE(lock);
return rc;
}
EXPORT_SYMBOL(ldlm_cli_enqueue_fini);
/**
* Estimate number of lock handles that would fit into request of given
* size. PAGE_SIZE-512 is to allow TCP/IP and LNET headers to fit into
* a single page on the send/receive side. XXX: 512 should be changed to
* more adequate value.
*/
static inline int ldlm_req_handles_avail(int req_size, int off)
{
int avail;
avail = min_t(int, LDLM_MAXREQSIZE, PAGE_CACHE_SIZE - 512) - req_size;
if (likely(avail >= 0))
avail /= (int)sizeof(struct lustre_handle);
else
avail = 0;
avail += LDLM_LOCKREQ_HANDLES - off;
return avail;
}
static inline int ldlm_capsule_handles_avail(struct req_capsule *pill,
enum req_location loc,
int off)
{
int size = req_capsule_msg_size(pill, loc);
return ldlm_req_handles_avail(size, off);
}
static inline int ldlm_format_handles_avail(struct obd_import *imp,
const struct req_format *fmt,
enum req_location loc, int off)
{
int size = req_capsule_fmt_size(imp->imp_msg_magic, fmt, loc);
return ldlm_req_handles_avail(size, off);
}
/**
* Cancel LRU locks and pack them into the enqueue request. Pack there the given
* \a count locks in \a cancels.
*
* This is to be called by functions preparing their own requests that
* might contain lists of locks to cancel in addition to actual operation
* that needs to be performed.
*/
int ldlm_prep_elc_req(struct obd_export *exp, struct ptlrpc_request *req,
int version, int opc, int canceloff,
struct list_head *cancels, int count)
{
struct ldlm_namespace *ns = exp->exp_obd->obd_namespace;
struct req_capsule *pill = &req->rq_pill;
struct ldlm_request *dlm = NULL;
int flags, avail, to_free, pack = 0;
LIST_HEAD(head);
int rc;
if (cancels == NULL)
cancels = &head;
if (ns_connect_cancelset(ns)) {
/* Estimate the amount of available space in the request. */
req_capsule_filled_sizes(pill, RCL_CLIENT);
avail = ldlm_capsule_handles_avail(pill, RCL_CLIENT, canceloff);
flags = ns_connect_lru_resize(ns) ?
LDLM_CANCEL_LRUR : LDLM_CANCEL_AGED;
to_free = !ns_connect_lru_resize(ns) &&
opc == LDLM_ENQUEUE ? 1 : 0;
/* Cancel LRU locks here _only_ if the server supports
* EARLY_CANCEL. Otherwise we have to send extra CANCEL
* RPC, which will make us slower. */
if (avail > count)
count += ldlm_cancel_lru_local(ns, cancels, to_free,
avail - count, 0, flags);
if (avail > count)
pack = count;
else
pack = avail;
req_capsule_set_size(pill, &RMF_DLM_REQ, RCL_CLIENT,
ldlm_request_bufsize(pack, opc));
}
rc = ptlrpc_request_pack(req, version, opc);
if (rc) {
ldlm_lock_list_put(cancels, l_bl_ast, count);
return rc;
}
if (ns_connect_cancelset(ns)) {
if (canceloff) {
dlm = req_capsule_client_get(pill, &RMF_DLM_REQ);
LASSERT(dlm);
/* Skip first lock handler in ldlm_request_pack(),
* this method will increment @lock_count according
* to the lock handle amount actually written to
* the buffer. */
dlm->lock_count = canceloff;
}
/* Pack into the request @pack lock handles. */
ldlm_cli_cancel_list(cancels, pack, req, 0);
/* Prepare and send separate cancel RPC for others. */
ldlm_cli_cancel_list(cancels, count - pack, NULL, 0);
} else {
ldlm_lock_list_put(cancels, l_bl_ast, count);
}
return 0;
}
EXPORT_SYMBOL(ldlm_prep_elc_req);
int ldlm_prep_enqueue_req(struct obd_export *exp, struct ptlrpc_request *req,
struct list_head *cancels, int count)
{
return ldlm_prep_elc_req(exp, req, LUSTRE_DLM_VERSION, LDLM_ENQUEUE,
LDLM_ENQUEUE_CANCEL_OFF, cancels, count);
}
EXPORT_SYMBOL(ldlm_prep_enqueue_req);
struct ptlrpc_request *ldlm_enqueue_pack(struct obd_export *exp, int lvb_len)
{
struct ptlrpc_request *req;
int rc;
req = ptlrpc_request_alloc(class_exp2cliimp(exp), &RQF_LDLM_ENQUEUE);
if (req == NULL)
return ERR_PTR(-ENOMEM);
rc = ldlm_prep_enqueue_req(exp, req, NULL, 0);
if (rc) {
ptlrpc_request_free(req);
return ERR_PTR(rc);
}
req_capsule_set_size(&req->rq_pill, &RMF_DLM_LVB, RCL_SERVER, lvb_len);
ptlrpc_request_set_replen(req);
return req;
}
EXPORT_SYMBOL(ldlm_enqueue_pack);
/**
* Client-side lock enqueue.
*
* If a request has some specific initialisation it is passed in \a reqp,
* otherwise it is created in ldlm_cli_enqueue.
*
* Supports sync and async requests, pass \a async flag accordingly. If a
* request was created in ldlm_cli_enqueue and it is the async request,
* pass it to the caller in \a reqp.
*/
int ldlm_cli_enqueue(struct obd_export *exp, struct ptlrpc_request **reqp,
struct ldlm_enqueue_info *einfo,
const struct ldlm_res_id *res_id,
ldlm_policy_data_t const *policy, __u64 *flags,
void *lvb, __u32 lvb_len, enum lvb_type lvb_type,
struct lustre_handle *lockh, int async)
{
struct ldlm_namespace *ns;
struct ldlm_lock *lock;
struct ldlm_request *body;
int is_replay = *flags & LDLM_FL_REPLAY;
int req_passed_in = 1;
int rc, err;
struct ptlrpc_request *req;
LASSERT(exp != NULL);
ns = exp->exp_obd->obd_namespace;
/* If we're replaying this lock, just check some invariants.
* If we're creating a new lock, get everything all setup nice. */
if (is_replay) {
lock = ldlm_handle2lock_long(lockh, 0);
LASSERT(lock != NULL);
LDLM_DEBUG(lock, "client-side enqueue START");
LASSERT(exp == lock->l_conn_export);
} else {
const struct ldlm_callback_suite cbs = {
.lcs_completion = einfo->ei_cb_cp,
.lcs_blocking = einfo->ei_cb_bl,
.lcs_glimpse = einfo->ei_cb_gl
};
lock = ldlm_lock_create(ns, res_id, einfo->ei_type,
einfo->ei_mode, &cbs, einfo->ei_cbdata,
lvb_len, lvb_type);
if (lock == NULL)
return -ENOMEM;
/* for the local lock, add the reference */
ldlm_lock_addref_internal(lock, einfo->ei_mode);
ldlm_lock2handle(lock, lockh);
if (policy != NULL)
lock->l_policy_data = *policy;
if (einfo->ei_type == LDLM_EXTENT)
lock->l_req_extent = policy->l_extent;
LDLM_DEBUG(lock, "client-side enqueue START, flags %llx\n",
*flags);
}
lock->l_conn_export = exp;
lock->l_export = NULL;
lock->l_blocking_ast = einfo->ei_cb_bl;
lock->l_flags |= (*flags & (LDLM_FL_NO_LRU | LDLM_FL_EXCL));
/* lock not sent to server yet */
if (reqp == NULL || *reqp == NULL) {
req = ptlrpc_request_alloc_pack(class_exp2cliimp(exp),
&RQF_LDLM_ENQUEUE,
LUSTRE_DLM_VERSION,
LDLM_ENQUEUE);
if (req == NULL) {
failed_lock_cleanup(ns, lock, einfo->ei_mode);
LDLM_LOCK_RELEASE(lock);
return -ENOMEM;
}
req_passed_in = 0;
if (reqp)
*reqp = req;
} else {
int len;
req = *reqp;
len = req_capsule_get_size(&req->rq_pill, &RMF_DLM_REQ,
RCL_CLIENT);
LASSERTF(len >= sizeof(*body), "buflen[%d] = %d, not %d\n",
DLM_LOCKREQ_OFF, len, (int)sizeof(*body));
}
/* Dump lock data into the request buffer */
body = req_capsule_client_get(&req->rq_pill, &RMF_DLM_REQ);
ldlm_lock2desc(lock, &body->lock_desc);
body->lock_flags = ldlm_flags_to_wire(*flags);
body->lock_handle[0] = *lockh;
/* Continue as normal. */
if (!req_passed_in) {
if (lvb_len > 0)
req_capsule_extend(&req->rq_pill,
&RQF_LDLM_ENQUEUE_LVB);
req_capsule_set_size(&req->rq_pill, &RMF_DLM_LVB, RCL_SERVER,
lvb_len);
ptlrpc_request_set_replen(req);
}
/*
* Liblustre client doesn't get extent locks, except for O_APPEND case
* where [0, OBD_OBJECT_EOF] lock is taken, or truncate, where
* [i_size, OBD_OBJECT_EOF] lock is taken.
*/
LASSERT(ergo(LIBLUSTRE_CLIENT, einfo->ei_type != LDLM_EXTENT ||
policy->l_extent.end == OBD_OBJECT_EOF));
if (async) {
LASSERT(reqp != NULL);
return 0;
}
LDLM_DEBUG(lock, "sending request");
rc = ptlrpc_queue_wait(req);
err = ldlm_cli_enqueue_fini(exp, req, einfo->ei_type, policy ? 1 : 0,
einfo->ei_mode, flags, lvb, lvb_len,
lockh, rc);
/* If ldlm_cli_enqueue_fini did not find the lock, we need to free
* one reference that we took */
if (err == -ENOLCK)
LDLM_LOCK_RELEASE(lock);
else
rc = err;
if (!req_passed_in && req != NULL) {
ptlrpc_req_finished(req);
if (reqp)
*reqp = NULL;
}
return rc;
}
EXPORT_SYMBOL(ldlm_cli_enqueue);
static int ldlm_cli_convert_local(struct ldlm_lock *lock, int new_mode,
__u32 *flags)
{
struct ldlm_resource *res;
int rc;
if (ns_is_client(ldlm_lock_to_ns(lock))) {
CERROR("Trying to cancel local lock\n");
LBUG();
}
LDLM_DEBUG(lock, "client-side local convert");
res = ldlm_lock_convert(lock, new_mode, flags);
if (res) {
ldlm_reprocess_all(res);
rc = 0;
} else {
rc = LUSTRE_EDEADLK;
}
LDLM_DEBUG(lock, "client-side local convert handler END");
LDLM_LOCK_PUT(lock);
return rc;
}
/* FIXME: one of ldlm_cli_convert or the server side should reject attempted
* conversion of locks which are on the waiting or converting queue */
/* Caller of this code is supposed to take care of lock readers/writers
accounting */
int ldlm_cli_convert(struct lustre_handle *lockh, int new_mode, __u32 *flags)
{
struct ldlm_request *body;
struct ldlm_reply *reply;
struct ldlm_lock *lock;
struct ldlm_resource *res;
struct ptlrpc_request *req;
int rc;
lock = ldlm_handle2lock(lockh);
if (!lock) {
LBUG();
return -EINVAL;
}
*flags = 0;
if (lock->l_conn_export == NULL)
return ldlm_cli_convert_local(lock, new_mode, flags);
LDLM_DEBUG(lock, "client-side convert");
req = ptlrpc_request_alloc_pack(class_exp2cliimp(lock->l_conn_export),
&RQF_LDLM_CONVERT, LUSTRE_DLM_VERSION,
LDLM_CONVERT);
if (req == NULL) {
LDLM_LOCK_PUT(lock);
return -ENOMEM;
}
body = req_capsule_client_get(&req->rq_pill, &RMF_DLM_REQ);
body->lock_handle[0] = lock->l_remote_handle;
body->lock_desc.l_req_mode = new_mode;
body->lock_flags = ldlm_flags_to_wire(*flags);
ptlrpc_request_set_replen(req);
rc = ptlrpc_queue_wait(req);
if (rc != ELDLM_OK)
goto out;
reply = req_capsule_server_get(&req->rq_pill, &RMF_DLM_REP);
if (reply == NULL) {
rc = -EPROTO;
goto out;
}
if (req->rq_status) {
rc = req->rq_status;
goto out;
}
res = ldlm_lock_convert(lock, new_mode, &reply->lock_flags);
if (res != NULL) {
ldlm_reprocess_all(res);
/* Go to sleep until the lock is granted. */
/* FIXME: or cancelled. */
if (lock->l_completion_ast) {
rc = lock->l_completion_ast(lock, LDLM_FL_WAIT_NOREPROC,
NULL);
if (rc)
goto out;
}
} else {
rc = LUSTRE_EDEADLK;
}
out:
LDLM_LOCK_PUT(lock);
ptlrpc_req_finished(req);
return rc;
}
EXPORT_SYMBOL(ldlm_cli_convert);
/**
* Cancel locks locally.
* Returns:
* \retval LDLM_FL_LOCAL_ONLY if there is no need for a CANCEL RPC to the server
* \retval LDLM_FL_CANCELING otherwise;
* \retval LDLM_FL_BL_AST if there is a need for a separate CANCEL RPC.
*/
static __u64 ldlm_cli_cancel_local(struct ldlm_lock *lock)
{
__u64 rc = LDLM_FL_LOCAL_ONLY;
if (lock->l_conn_export) {
bool local_only;
LDLM_DEBUG(lock, "client-side cancel");
/* Set this flag to prevent others from getting new references*/
lock_res_and_lock(lock);
lock->l_flags |= LDLM_FL_CBPENDING;
local_only = !!(lock->l_flags &
(LDLM_FL_LOCAL_ONLY|LDLM_FL_CANCEL_ON_BLOCK));
ldlm_cancel_callback(lock);
rc = (lock->l_flags & LDLM_FL_BL_AST) ?
LDLM_FL_BL_AST : LDLM_FL_CANCELING;
unlock_res_and_lock(lock);
if (local_only) {
CDEBUG(D_DLMTRACE, "not sending request (at caller's instruction)\n");
rc = LDLM_FL_LOCAL_ONLY;
}
ldlm_lock_cancel(lock);
} else {
if (ns_is_client(ldlm_lock_to_ns(lock))) {
LDLM_ERROR(lock, "Trying to cancel local lock");
LBUG();
}
LDLM_DEBUG(lock, "server-side local cancel");
ldlm_lock_cancel(lock);
ldlm_reprocess_all(lock->l_resource);
}
return rc;
}
/**
* Pack \a count locks in \a head into ldlm_request buffer of request \a req.
*/
static void ldlm_cancel_pack(struct ptlrpc_request *req,
struct list_head *head, int count)
{
struct ldlm_request *dlm;
struct ldlm_lock *lock;
int max, packed = 0;
dlm = req_capsule_client_get(&req->rq_pill, &RMF_DLM_REQ);
LASSERT(dlm != NULL);
/* Check the room in the request buffer. */
max = req_capsule_get_size(&req->rq_pill, &RMF_DLM_REQ, RCL_CLIENT) -
sizeof(struct ldlm_request);
max /= sizeof(struct lustre_handle);
max += LDLM_LOCKREQ_HANDLES;
LASSERT(max >= dlm->lock_count + count);
/* XXX: it would be better to pack lock handles grouped by resource.
* so that the server cancel would call filter_lvbo_update() less
* frequently. */
list_for_each_entry(lock, head, l_bl_ast) {
if (!count--)
break;
LASSERT(lock->l_conn_export);
/* Pack the lock handle to the given request buffer. */
LDLM_DEBUG(lock, "packing");
dlm->lock_handle[dlm->lock_count++] = lock->l_remote_handle;
packed++;
}
CDEBUG(D_DLMTRACE, "%d locks packed\n", packed);
}
/**
* Prepare and send a batched cancel RPC. It will include \a count lock
* handles of locks given in \a cancels list. */
int ldlm_cli_cancel_req(struct obd_export *exp, struct list_head *cancels,
int count, ldlm_cancel_flags_t flags)
{
struct ptlrpc_request *req = NULL;
struct obd_import *imp;
int free, sent = 0;
int rc = 0;
LASSERT(exp != NULL);
LASSERT(count > 0);
CFS_FAIL_TIMEOUT(OBD_FAIL_LDLM_PAUSE_CANCEL, cfs_fail_val);
if (CFS_FAIL_CHECK(OBD_FAIL_LDLM_CANCEL_RACE))
return count;
free = ldlm_format_handles_avail(class_exp2cliimp(exp),
&RQF_LDLM_CANCEL, RCL_CLIENT, 0);
if (count > free)
count = free;
while (1) {
imp = class_exp2cliimp(exp);
if (imp == NULL || imp->imp_invalid) {
CDEBUG(D_DLMTRACE,
"skipping cancel on invalid import %p\n", imp);
return count;
}
req = ptlrpc_request_alloc(imp, &RQF_LDLM_CANCEL);
if (req == NULL) {
rc = -ENOMEM;
goto out;
}
req_capsule_filled_sizes(&req->rq_pill, RCL_CLIENT);
req_capsule_set_size(&req->rq_pill, &RMF_DLM_REQ, RCL_CLIENT,
ldlm_request_bufsize(count, LDLM_CANCEL));
rc = ptlrpc_request_pack(req, LUSTRE_DLM_VERSION, LDLM_CANCEL);
if (rc) {
ptlrpc_request_free(req);
goto out;
}
req->rq_request_portal = LDLM_CANCEL_REQUEST_PORTAL;
req->rq_reply_portal = LDLM_CANCEL_REPLY_PORTAL;
ptlrpc_at_set_req_timeout(req);
ldlm_cancel_pack(req, cancels, count);
ptlrpc_request_set_replen(req);
if (flags & LCF_ASYNC) {
ptlrpcd_add_req(req, PDL_POLICY_LOCAL, -1);
sent = count;
goto out;
} else {
rc = ptlrpc_queue_wait(req);
}
if (rc == LUSTRE_ESTALE) {
CDEBUG(D_DLMTRACE, "client/server (nid %s) out of sync -- not fatal\n",
libcfs_nid2str(req->rq_import->
imp_connection->c_peer.nid));
rc = 0;
} else if (rc == -ETIMEDOUT && /* check there was no reconnect*/
req->rq_import_generation == imp->imp_generation) {
ptlrpc_req_finished(req);
continue;
} else if (rc != ELDLM_OK) {
/* -ESHUTDOWN is common on umount */
CDEBUG_LIMIT(rc == -ESHUTDOWN ? D_DLMTRACE : D_ERROR,
"Got rc %d from cancel RPC: canceling anyway\n",
rc);
break;
}
sent = count;
break;
}
ptlrpc_req_finished(req);
out:
return sent ? sent : rc;
}
EXPORT_SYMBOL(ldlm_cli_cancel_req);
static inline struct ldlm_pool *ldlm_imp2pl(struct obd_import *imp)
{
LASSERT(imp != NULL);
return &imp->imp_obd->obd_namespace->ns_pool;
}
/**
* Update client's OBD pool related fields with new SLV and Limit from \a req.
*/
int ldlm_cli_update_pool(struct ptlrpc_request *req)
{
struct obd_device *obd;
__u64 new_slv;
__u32 new_limit;
if (unlikely(!req->rq_import || !req->rq_import->imp_obd ||
!imp_connect_lru_resize(req->rq_import))) {
/*
* Do nothing for corner cases.
*/
return 0;
}
/* In some cases RPC may contain SLV and limit zeroed out. This
* is the case when server does not support LRU resize feature.
* This is also possible in some recovery cases when server-side
* reqs have no reference to the OBD export and thus access to
* server-side namespace is not possible. */
if (lustre_msg_get_slv(req->rq_repmsg) == 0 ||
lustre_msg_get_limit(req->rq_repmsg) == 0) {
DEBUG_REQ(D_HA, req,
"Zero SLV or Limit found (SLV: %llu, Limit: %u)",
lustre_msg_get_slv(req->rq_repmsg),
lustre_msg_get_limit(req->rq_repmsg));
return 0;
}
new_limit = lustre_msg_get_limit(req->rq_repmsg);
new_slv = lustre_msg_get_slv(req->rq_repmsg);
obd = req->rq_import->imp_obd;
/* Set new SLV and limit in OBD fields to make them accessible
* to the pool thread. We do not access obd_namespace and pool
* directly here as there is no reliable way to make sure that
* they are still alive at cleanup time. Evil races are possible
* which may cause Oops at that time. */
write_lock(&obd->obd_pool_lock);
obd->obd_pool_slv = new_slv;
obd->obd_pool_limit = new_limit;
write_unlock(&obd->obd_pool_lock);
return 0;
}
EXPORT_SYMBOL(ldlm_cli_update_pool);
/**
* Client side lock cancel.
*
* Lock must not have any readers or writers by this time.
*/
int ldlm_cli_cancel(struct lustre_handle *lockh,
ldlm_cancel_flags_t cancel_flags)
{
struct obd_export *exp;
int avail, flags, count = 1;
__u64 rc = 0;
struct ldlm_namespace *ns;
struct ldlm_lock *lock;
LIST_HEAD(cancels);
/* concurrent cancels on the same handle can happen */
lock = ldlm_handle2lock_long(lockh, LDLM_FL_CANCELING);
if (lock == NULL) {
LDLM_DEBUG_NOLOCK("lock is already being destroyed\n");
return 0;
}
rc = ldlm_cli_cancel_local(lock);
if (rc == LDLM_FL_LOCAL_ONLY || cancel_flags & LCF_LOCAL) {
LDLM_LOCK_RELEASE(lock);
return 0;
}
/* Even if the lock is marked as LDLM_FL_BL_AST, this is a LDLM_CANCEL
* RPC which goes to canceld portal, so we can cancel other LRU locks
* here and send them all as one LDLM_CANCEL RPC. */
LASSERT(list_empty(&lock->l_bl_ast));
list_add(&lock->l_bl_ast, &cancels);
exp = lock->l_conn_export;
if (exp_connect_cancelset(exp)) {
avail = ldlm_format_handles_avail(class_exp2cliimp(exp),
&RQF_LDLM_CANCEL,
RCL_CLIENT, 0);
LASSERT(avail > 0);
ns = ldlm_lock_to_ns(lock);
flags = ns_connect_lru_resize(ns) ?
LDLM_CANCEL_LRUR : LDLM_CANCEL_AGED;
count += ldlm_cancel_lru_local(ns, &cancels, 0, avail - 1,
LCF_BL_AST, flags);
}
ldlm_cli_cancel_list(&cancels, count, NULL, cancel_flags);
return 0;
}
EXPORT_SYMBOL(ldlm_cli_cancel);
/**
* Locally cancel up to \a count locks in list \a cancels.
* Return the number of cancelled locks.
*/
int ldlm_cli_cancel_list_local(struct list_head *cancels, int count,
ldlm_cancel_flags_t flags)
{
LIST_HEAD(head);
struct ldlm_lock *lock, *next;
int left = 0, bl_ast = 0;
__u64 rc;
left = count;
list_for_each_entry_safe(lock, next, cancels, l_bl_ast) {
if (left-- == 0)
break;
if (flags & LCF_LOCAL) {
rc = LDLM_FL_LOCAL_ONLY;
ldlm_lock_cancel(lock);
} else {
rc = ldlm_cli_cancel_local(lock);
}
/* Until we have compound requests and can send LDLM_CANCEL
* requests batched with generic RPCs, we need to send cancels
* with the LDLM_FL_BL_AST flag in a separate RPC from
* the one being generated now. */
if (!(flags & LCF_BL_AST) && (rc == LDLM_FL_BL_AST)) {
LDLM_DEBUG(lock, "Cancel lock separately");
list_del_init(&lock->l_bl_ast);
list_add(&lock->l_bl_ast, &head);
bl_ast++;
continue;
}
if (rc == LDLM_FL_LOCAL_ONLY) {
/* CANCEL RPC should not be sent to server. */
list_del_init(&lock->l_bl_ast);
LDLM_LOCK_RELEASE(lock);
count--;
}
}
if (bl_ast > 0) {
count -= bl_ast;
ldlm_cli_cancel_list(&head, bl_ast, NULL, 0);
}
return count;
}
EXPORT_SYMBOL(ldlm_cli_cancel_list_local);
/**
* Cancel as many locks as possible w/o sending any RPCs (e.g. to write back
* dirty data, to close a file, ...) or waiting for any RPCs in-flight (e.g.
* readahead requests, ...)
*/
static ldlm_policy_res_t ldlm_cancel_no_wait_policy(struct ldlm_namespace *ns,
struct ldlm_lock *lock,
int unused, int added,
int count)
{
ldlm_policy_res_t result = LDLM_POLICY_CANCEL_LOCK;
ldlm_cancel_for_recovery cb = ns->ns_cancel_for_recovery;
lock_res_and_lock(lock);
/* don't check added & count since we want to process all locks
* from unused list */
switch (lock->l_resource->lr_type) {
case LDLM_EXTENT:
case LDLM_IBITS:
if (cb && cb(lock))
break;
default:
result = LDLM_POLICY_SKIP_LOCK;
lock->l_flags |= LDLM_FL_SKIPPED;
break;
}
unlock_res_and_lock(lock);
return result;
}
/**
* Callback function for LRU-resize policy. Decides whether to keep
* \a lock in LRU for current \a LRU size \a unused, added in current
* scan \a added and number of locks to be preferably canceled \a count.
*
* \retval LDLM_POLICY_KEEP_LOCK keep lock in LRU in stop scanning
*
* \retval LDLM_POLICY_CANCEL_LOCK cancel lock from LRU
*/
static ldlm_policy_res_t ldlm_cancel_lrur_policy(struct ldlm_namespace *ns,
struct ldlm_lock *lock,
int unused, int added,
int count)
{
unsigned long cur = cfs_time_current();
struct ldlm_pool *pl = &ns->ns_pool;
__u64 slv, lvf, lv;
unsigned long la;
/* Stop LRU processing when we reach past @count or have checked all
* locks in LRU. */
if (count && added >= count)
return LDLM_POLICY_KEEP_LOCK;
slv = ldlm_pool_get_slv(pl);
lvf = ldlm_pool_get_lvf(pl);
la = cfs_duration_sec(cfs_time_sub(cur,
lock->l_last_used));
lv = lvf * la * unused;
/* Inform pool about current CLV to see it via proc. */
ldlm_pool_set_clv(pl, lv);
/* Stop when SLV is not yet come from server or lv is smaller than
* it is. */
return (slv == 0 || lv < slv) ?
LDLM_POLICY_KEEP_LOCK : LDLM_POLICY_CANCEL_LOCK;
}
/**
* Callback function for proc used policy. Makes decision whether to keep
* \a lock in LRU for current \a LRU size \a unused, added in current scan \a
* added and number of locks to be preferably canceled \a count.
*
* \retval LDLM_POLICY_KEEP_LOCK keep lock in LRU in stop scanning
*
* \retval LDLM_POLICY_CANCEL_LOCK cancel lock from LRU
*/
static ldlm_policy_res_t ldlm_cancel_passed_policy(struct ldlm_namespace *ns,
struct ldlm_lock *lock,
int unused, int added,
int count)
{
/* Stop LRU processing when we reach past @count or have checked all
* locks in LRU. */
return (added >= count) ?
LDLM_POLICY_KEEP_LOCK : LDLM_POLICY_CANCEL_LOCK;
}
/**
* Callback function for aged policy. Makes decision whether to keep \a lock in
* LRU for current LRU size \a unused, added in current scan \a added and
* number of locks to be preferably canceled \a count.
*
* \retval LDLM_POLICY_KEEP_LOCK keep lock in LRU in stop scanning
*
* \retval LDLM_POLICY_CANCEL_LOCK cancel lock from LRU
*/
static ldlm_policy_res_t ldlm_cancel_aged_policy(struct ldlm_namespace *ns,
struct ldlm_lock *lock,
int unused, int added,
int count)
{
/* Stop LRU processing if young lock is found and we reach past count */
return ((added >= count) &&
time_before(cfs_time_current(),
cfs_time_add(lock->l_last_used, ns->ns_max_age))) ?
LDLM_POLICY_KEEP_LOCK : LDLM_POLICY_CANCEL_LOCK;
}
/**
* Callback function for default policy. Makes decision whether to keep \a lock
* in LRU for current LRU size \a unused, added in current scan \a added and
* number of locks to be preferably canceled \a count.
*
* \retval LDLM_POLICY_KEEP_LOCK keep lock in LRU in stop scanning
*
* \retval LDLM_POLICY_CANCEL_LOCK cancel lock from LRU
*/
static ldlm_policy_res_t ldlm_cancel_default_policy(struct ldlm_namespace *ns,
struct ldlm_lock *lock,
int unused, int added,
int count)
{
/* Stop LRU processing when we reach past count or have checked all
* locks in LRU. */
return (added >= count) ?
LDLM_POLICY_KEEP_LOCK : LDLM_POLICY_CANCEL_LOCK;
}
typedef ldlm_policy_res_t (*ldlm_cancel_lru_policy_t)(struct ldlm_namespace *,
struct ldlm_lock *, int,
int, int);
static ldlm_cancel_lru_policy_t
ldlm_cancel_lru_policy(struct ldlm_namespace *ns, int flags)
{
if (flags & LDLM_CANCEL_NO_WAIT)
return ldlm_cancel_no_wait_policy;
if (ns_connect_lru_resize(ns)) {
if (flags & LDLM_CANCEL_SHRINK)
/* We kill passed number of old locks. */
return ldlm_cancel_passed_policy;
else if (flags & LDLM_CANCEL_LRUR)
return ldlm_cancel_lrur_policy;
else if (flags & LDLM_CANCEL_PASSED)
return ldlm_cancel_passed_policy;
} else {
if (flags & LDLM_CANCEL_AGED)
return ldlm_cancel_aged_policy;
}
return ldlm_cancel_default_policy;
}
/**
* - Free space in LRU for \a count new locks,
* redundant unused locks are canceled locally;
* - also cancel locally unused aged locks;
* - do not cancel more than \a max locks;
* - GET the found locks and add them into the \a cancels list.
*
* A client lock can be added to the l_bl_ast list only when it is
* marked LDLM_FL_CANCELING. Otherwise, somebody is already doing
* CANCEL. There are the following use cases:
* ldlm_cancel_resource_local(), ldlm_cancel_lru_local() and
* ldlm_cli_cancel(), which check and set this flag properly. As any
* attempt to cancel a lock rely on this flag, l_bl_ast list is accessed
* later without any special locking.
*
* Calling policies for enabled LRU resize:
* ----------------------------------------
* flags & LDLM_CANCEL_LRUR - use LRU resize policy (SLV from server) to
* cancel not more than \a count locks;
*
* flags & LDLM_CANCEL_PASSED - cancel \a count number of old locks (located at
* the beginning of LRU list);
*
* flags & LDLM_CANCEL_SHRINK - cancel not more than \a count locks according to
* memory pressure policy function;
*
* flags & LDLM_CANCEL_AGED - cancel \a count locks according to "aged policy".
*
* flags & LDLM_CANCEL_NO_WAIT - cancel as many unused locks as possible
* (typically before replaying locks) w/o
* sending any RPCs or waiting for any
* outstanding RPC to complete.
*/
static int ldlm_prepare_lru_list(struct ldlm_namespace *ns,
struct list_head *cancels, int count, int max,
int flags)
{
ldlm_cancel_lru_policy_t pf;
struct ldlm_lock *lock, *next;
int added = 0, unused, remained;
spin_lock(&ns->ns_lock);
unused = ns->ns_nr_unused;
remained = unused;
if (!ns_connect_lru_resize(ns))
count += unused - ns->ns_max_unused;
pf = ldlm_cancel_lru_policy(ns, flags);
LASSERT(pf != NULL);
while (!list_empty(&ns->ns_unused_list)) {
ldlm_policy_res_t result;
/* all unused locks */
if (remained-- <= 0)
break;
/* For any flags, stop scanning if @max is reached. */
if (max && added >= max)
break;
list_for_each_entry_safe(lock, next, &ns->ns_unused_list,
l_lru) {
/* No locks which got blocking requests. */
LASSERT(!(lock->l_flags & LDLM_FL_BL_AST));
if (flags & LDLM_CANCEL_NO_WAIT &&
lock->l_flags & LDLM_FL_SKIPPED)
/* already processed */
continue;
/* Somebody is already doing CANCEL. No need for this
* lock in LRU, do not traverse it again. */
if (!(lock->l_flags & LDLM_FL_CANCELING))
break;
ldlm_lock_remove_from_lru_nolock(lock);
}
if (&lock->l_lru == &ns->ns_unused_list)
break;
LDLM_LOCK_GET(lock);
spin_unlock(&ns->ns_lock);
lu_ref_add(&lock->l_reference, __func__, current);
/* Pass the lock through the policy filter and see if it
* should stay in LRU.
*
* Even for shrinker policy we stop scanning if
* we find a lock that should stay in the cache.
* We should take into account lock age anyway
* as a new lock is a valuable resource even if
* it has a low weight.
*
* That is, for shrinker policy we drop only
* old locks, but additionally choose them by
* their weight. Big extent locks will stay in
* the cache. */
result = pf(ns, lock, unused, added, count);
if (result == LDLM_POLICY_KEEP_LOCK) {
lu_ref_del(&lock->l_reference,
__func__, current);
LDLM_LOCK_RELEASE(lock);
spin_lock(&ns->ns_lock);
break;
}
if (result == LDLM_POLICY_SKIP_LOCK) {
lu_ref_del(&lock->l_reference,
__func__, current);
LDLM_LOCK_RELEASE(lock);
spin_lock(&ns->ns_lock);
continue;
}
lock_res_and_lock(lock);
/* Check flags again under the lock. */
if ((lock->l_flags & LDLM_FL_CANCELING) ||
(ldlm_lock_remove_from_lru(lock) == 0)) {
/* Another thread is removing lock from LRU, or
* somebody is already doing CANCEL, or there
* is a blocking request which will send cancel
* by itself, or the lock is no longer unused. */
unlock_res_and_lock(lock);
lu_ref_del(&lock->l_reference,
__func__, current);
LDLM_LOCK_RELEASE(lock);
spin_lock(&ns->ns_lock);
continue;
}
LASSERT(!lock->l_readers && !lock->l_writers);
/* If we have chosen to cancel this lock voluntarily, we
* better send cancel notification to server, so that it
* frees appropriate state. This might lead to a race
* where while we are doing cancel here, server is also
* silently cancelling this lock. */
lock->l_flags &= ~LDLM_FL_CANCEL_ON_BLOCK;
/* Setting the CBPENDING flag is a little misleading,
* but prevents an important race; namely, once
* CBPENDING is set, the lock can accumulate no more
* readers/writers. Since readers and writers are
* already zero here, ldlm_lock_decref() won't see
* this flag and call l_blocking_ast */
lock->l_flags |= LDLM_FL_CBPENDING | LDLM_FL_CANCELING;
/* We can't re-add to l_lru as it confuses the
* refcounting in ldlm_lock_remove_from_lru() if an AST
* arrives after we drop lr_lock below. We use l_bl_ast
* and can't use l_pending_chain as it is used both on
* server and client nevertheless bug 5666 says it is
* used only on server */
LASSERT(list_empty(&lock->l_bl_ast));
list_add(&lock->l_bl_ast, cancels);
unlock_res_and_lock(lock);
lu_ref_del(&lock->l_reference, __func__, current);
spin_lock(&ns->ns_lock);
added++;
unused--;
}
spin_unlock(&ns->ns_lock);
return added;
}
int ldlm_cancel_lru_local(struct ldlm_namespace *ns, struct list_head *cancels,
int count, int max, ldlm_cancel_flags_t cancel_flags,
int flags)
{
int added;
added = ldlm_prepare_lru_list(ns, cancels, count, max, flags);
if (added <= 0)
return added;
return ldlm_cli_cancel_list_local(cancels, added, cancel_flags);
}
/**
* Cancel at least \a nr locks from given namespace LRU.
*
* When called with LCF_ASYNC the blocking callback will be handled
* in a thread and this function will return after the thread has been
* asked to call the callback. When called with LCF_ASYNC the blocking
* callback will be performed in this function.
*/
int ldlm_cancel_lru(struct ldlm_namespace *ns, int nr,
ldlm_cancel_flags_t cancel_flags,
int flags)
{
LIST_HEAD(cancels);
int count, rc;
/* Just prepare the list of locks, do not actually cancel them yet.
* Locks are cancelled later in a separate thread. */
count = ldlm_prepare_lru_list(ns, &cancels, nr, 0, flags);
rc = ldlm_bl_to_thread_list(ns, NULL, &cancels, count, cancel_flags);
if (rc == 0)
return count;
return 0;
}
/**
* Find and cancel locally unused locks found on resource, matched to the
* given policy, mode. GET the found locks and add them into the \a cancels
* list.
*/
int ldlm_cancel_resource_local(struct ldlm_resource *res,
struct list_head *cancels,
ldlm_policy_data_t *policy,
ldlm_mode_t mode, __u64 lock_flags,
ldlm_cancel_flags_t cancel_flags, void *opaque)
{
struct ldlm_lock *lock;
int count = 0;
lock_res(res);
list_for_each_entry(lock, &res->lr_granted, l_res_link) {
if (opaque != NULL && lock->l_ast_data != opaque) {
LDLM_ERROR(lock, "data %p doesn't match opaque %p",
lock->l_ast_data, opaque);
continue;
}
if (lock->l_readers || lock->l_writers)
continue;
/* If somebody is already doing CANCEL, or blocking AST came,
* skip this lock. */
if (lock->l_flags & LDLM_FL_BL_AST ||
lock->l_flags & LDLM_FL_CANCELING)
continue;
if (lockmode_compat(lock->l_granted_mode, mode))
continue;
/* If policy is given and this is IBITS lock, add to list only
* those locks that match by policy. */
if (policy && (lock->l_resource->lr_type == LDLM_IBITS) &&
!(lock->l_policy_data.l_inodebits.bits &
policy->l_inodebits.bits))
continue;
/* See CBPENDING comment in ldlm_cancel_lru */
lock->l_flags |= LDLM_FL_CBPENDING | LDLM_FL_CANCELING |
lock_flags;
LASSERT(list_empty(&lock->l_bl_ast));
list_add(&lock->l_bl_ast, cancels);
LDLM_LOCK_GET(lock);
count++;
}
unlock_res(res);
return ldlm_cli_cancel_list_local(cancels, count, cancel_flags);
}
EXPORT_SYMBOL(ldlm_cancel_resource_local);
/**
* Cancel client-side locks from a list and send/prepare cancel RPCs to the
* server.
* If \a req is NULL, send CANCEL request to server with handles of locks
* in the \a cancels. If EARLY_CANCEL is not supported, send CANCEL requests
* separately per lock.
* If \a req is not NULL, put handles of locks in \a cancels into the request
* buffer at the offset \a off.
* Destroy \a cancels at the end.
*/
int ldlm_cli_cancel_list(struct list_head *cancels, int count,
struct ptlrpc_request *req, ldlm_cancel_flags_t flags)
{
struct ldlm_lock *lock;
int res = 0;
if (list_empty(cancels) || count == 0)
return 0;
/* XXX: requests (both batched and not) could be sent in parallel.
* Usually it is enough to have just 1 RPC, but it is possible that
* there are too many locks to be cancelled in LRU or on a resource.
* It would also speed up the case when the server does not support
* the feature. */
while (count > 0) {
LASSERT(!list_empty(cancels));
lock = list_entry(cancels->next, struct ldlm_lock,
l_bl_ast);
LASSERT(lock->l_conn_export);
if (exp_connect_cancelset(lock->l_conn_export)) {
res = count;
if (req)
ldlm_cancel_pack(req, cancels, count);
else
res = ldlm_cli_cancel_req(lock->l_conn_export,
cancels, count,
flags);
} else {
res = ldlm_cli_cancel_req(lock->l_conn_export,
cancels, 1, flags);
}
if (res < 0) {
CDEBUG_LIMIT(res == -ESHUTDOWN ? D_DLMTRACE : D_ERROR,
"ldlm_cli_cancel_list: %d\n", res);
res = count;
}
count -= res;
ldlm_lock_list_put(cancels, l_bl_ast, res);
}
LASSERT(count == 0);
return 0;
}
EXPORT_SYMBOL(ldlm_cli_cancel_list);
/**
* Cancel all locks on a resource that have 0 readers/writers.
*
* If flags & LDLM_FL_LOCAL_ONLY, throw the locks away without trying
* to notify the server. */
int ldlm_cli_cancel_unused_resource(struct ldlm_namespace *ns,
const struct ldlm_res_id *res_id,
ldlm_policy_data_t *policy,
ldlm_mode_t mode,
ldlm_cancel_flags_t flags,
void *opaque)
{
struct ldlm_resource *res;
LIST_HEAD(cancels);
int count;
int rc;
res = ldlm_resource_get(ns, NULL, res_id, 0, 0);
if (res == NULL) {
/* This is not a problem. */
CDEBUG(D_INFO, "No resource %llu\n", res_id->name[0]);
return 0;
}
LDLM_RESOURCE_ADDREF(res);
count = ldlm_cancel_resource_local(res, &cancels, policy, mode,
0, flags | LCF_BL_AST, opaque);
rc = ldlm_cli_cancel_list(&cancels, count, NULL, flags);
if (rc != ELDLM_OK)
CERROR("canceling unused lock "DLDLMRES": rc = %d\n",
PLDLMRES(res), rc);
LDLM_RESOURCE_DELREF(res);
ldlm_resource_putref(res);
return 0;
}
EXPORT_SYMBOL(ldlm_cli_cancel_unused_resource);
struct ldlm_cli_cancel_arg {
int lc_flags;
void *lc_opaque;
};
static int ldlm_cli_hash_cancel_unused(struct cfs_hash *hs,
struct cfs_hash_bd *bd,
struct hlist_node *hnode, void *arg)
{
struct ldlm_resource *res = cfs_hash_object(hs, hnode);
struct ldlm_cli_cancel_arg *lc = arg;
ldlm_cli_cancel_unused_resource(ldlm_res_to_ns(res), &res->lr_name,
NULL, LCK_MINMODE,
lc->lc_flags, lc->lc_opaque);
/* must return 0 for hash iteration */
return 0;
}
/**
* Cancel all locks on a namespace (or a specific resource, if given)
* that have 0 readers/writers.
*
* If flags & LCF_LOCAL, throw the locks away without trying
* to notify the server. */
int ldlm_cli_cancel_unused(struct ldlm_namespace *ns,
const struct ldlm_res_id *res_id,
ldlm_cancel_flags_t flags, void *opaque)
{
struct ldlm_cli_cancel_arg arg = {
.lc_flags = flags,
.lc_opaque = opaque,
};
if (ns == NULL)
return ELDLM_OK;
if (res_id != NULL) {
return ldlm_cli_cancel_unused_resource(ns, res_id, NULL,
LCK_MINMODE, flags,
opaque);
} else {
cfs_hash_for_each_nolock(ns->ns_rs_hash,
ldlm_cli_hash_cancel_unused, &arg);
return ELDLM_OK;
}
}
EXPORT_SYMBOL(ldlm_cli_cancel_unused);
/* Lock iterators. */
int ldlm_resource_foreach(struct ldlm_resource *res, ldlm_iterator_t iter,
void *closure)
{
struct list_head *tmp, *next;
struct ldlm_lock *lock;
int rc = LDLM_ITER_CONTINUE;
if (!res)
return LDLM_ITER_CONTINUE;
lock_res(res);
list_for_each_safe(tmp, next, &res->lr_granted) {
lock = list_entry(tmp, struct ldlm_lock, l_res_link);
if (iter(lock, closure) == LDLM_ITER_STOP) {
rc = LDLM_ITER_STOP;
goto out;
}
}
list_for_each_safe(tmp, next, &res->lr_converting) {
lock = list_entry(tmp, struct ldlm_lock, l_res_link);
if (iter(lock, closure) == LDLM_ITER_STOP) {
rc = LDLM_ITER_STOP;
goto out;
}
}
list_for_each_safe(tmp, next, &res->lr_waiting) {
lock = list_entry(tmp, struct ldlm_lock, l_res_link);
if (iter(lock, closure) == LDLM_ITER_STOP) {
rc = LDLM_ITER_STOP;
goto out;
}
}
out:
unlock_res(res);
return rc;
}
EXPORT_SYMBOL(ldlm_resource_foreach);
struct iter_helper_data {
ldlm_iterator_t iter;
void *closure;
};
static int ldlm_iter_helper(struct ldlm_lock *lock, void *closure)
{
struct iter_helper_data *helper = closure;
return helper->iter(lock, helper->closure);
}
static int ldlm_res_iter_helper(struct cfs_hash *hs, struct cfs_hash_bd *bd,
struct hlist_node *hnode, void *arg)
{
struct ldlm_resource *res = cfs_hash_object(hs, hnode);
return ldlm_resource_foreach(res, ldlm_iter_helper, arg) ==
LDLM_ITER_STOP;
}
void ldlm_namespace_foreach(struct ldlm_namespace *ns,
ldlm_iterator_t iter, void *closure)
{
struct iter_helper_data helper = {
.iter = iter,
.closure = closure,
};
cfs_hash_for_each_nolock(ns->ns_rs_hash,
ldlm_res_iter_helper, &helper);
}
EXPORT_SYMBOL(ldlm_namespace_foreach);
/* non-blocking function to manipulate a lock whose cb_data is being put away.
* return 0: find no resource
* > 0: must be LDLM_ITER_STOP/LDLM_ITER_CONTINUE.
* < 0: errors
*/
int ldlm_resource_iterate(struct ldlm_namespace *ns,
const struct ldlm_res_id *res_id,
ldlm_iterator_t iter, void *data)
{
struct ldlm_resource *res;
int rc;
if (ns == NULL) {
CERROR("must pass in namespace\n");
LBUG();
}
res = ldlm_resource_get(ns, NULL, res_id, 0, 0);
if (res == NULL)
return 0;
LDLM_RESOURCE_ADDREF(res);
rc = ldlm_resource_foreach(res, iter, data);
LDLM_RESOURCE_DELREF(res);
ldlm_resource_putref(res);
return rc;
}
EXPORT_SYMBOL(ldlm_resource_iterate);
/* Lock replay */
static int ldlm_chain_lock_for_replay(struct ldlm_lock *lock, void *closure)
{
struct list_head *list = closure;
/* we use l_pending_chain here, because it's unused on clients. */
LASSERTF(list_empty(&lock->l_pending_chain),
"lock %p next %p prev %p\n",
lock, &lock->l_pending_chain.next,
&lock->l_pending_chain.prev);
/* bug 9573: don't replay locks left after eviction, or
* bug 17614: locks being actively cancelled. Get a reference
* on a lock so that it does not disappear under us (e.g. due to cancel)
*/
if (!(lock->l_flags & (LDLM_FL_FAILED|LDLM_FL_CANCELING))) {
list_add(&lock->l_pending_chain, list);
LDLM_LOCK_GET(lock);
}
return LDLM_ITER_CONTINUE;
}
static int replay_lock_interpret(const struct lu_env *env,
struct ptlrpc_request *req,
struct ldlm_async_args *aa, int rc)
{
struct ldlm_lock *lock;
struct ldlm_reply *reply;
struct obd_export *exp;
atomic_dec(&req->rq_import->imp_replay_inflight);
if (rc != ELDLM_OK)
goto out;
reply = req_capsule_server_get(&req->rq_pill, &RMF_DLM_REP);
if (reply == NULL) {
rc = -EPROTO;
goto out;
}
lock = ldlm_handle2lock(&aa->lock_handle);
if (!lock) {
CERROR("received replay ack for unknown local cookie %#llx remote cookie %#llx from server %s id %s\n",
aa->lock_handle.cookie, reply->lock_handle.cookie,
req->rq_export->exp_client_uuid.uuid,
libcfs_id2str(req->rq_peer));
rc = -ESTALE;
goto out;
}
/* Key change rehash lock in per-export hash with new key */
exp = req->rq_export;
if (exp && exp->exp_lock_hash) {
/* In the function below, .hs_keycmp resolves to
* ldlm_export_lock_keycmp() */
/* coverity[overrun-buffer-val] */
cfs_hash_rehash_key(exp->exp_lock_hash,
&lock->l_remote_handle,
&reply->lock_handle,
&lock->l_exp_hash);
} else {
lock->l_remote_handle = reply->lock_handle;
}
LDLM_DEBUG(lock, "replayed lock:");
ptlrpc_import_recovery_state_machine(req->rq_import);
LDLM_LOCK_PUT(lock);
out:
if (rc != ELDLM_OK)
ptlrpc_connect_import(req->rq_import);
return rc;
}
static int replay_one_lock(struct obd_import *imp, struct ldlm_lock *lock)
{
struct ptlrpc_request *req;
struct ldlm_async_args *aa;
struct ldlm_request *body;
int flags;
/* Bug 11974: Do not replay a lock which is actively being canceled */
if (lock->l_flags & LDLM_FL_CANCELING) {
LDLM_DEBUG(lock, "Not replaying canceled lock:");
return 0;
}
/* If this is reply-less callback lock, we cannot replay it, since
* server might have long dropped it, but notification of that event was
* lost by network. (and server granted conflicting lock already) */
if (lock->l_flags & LDLM_FL_CANCEL_ON_BLOCK) {
LDLM_DEBUG(lock, "Not replaying reply-less lock:");
ldlm_lock_cancel(lock);
return 0;
}
/*
* If granted mode matches the requested mode, this lock is granted.
*
* If they differ, but we have a granted mode, then we were granted
* one mode and now want another: ergo, converting.
*
* If we haven't been granted anything and are on a resource list,
* then we're blocked/waiting.
*
* If we haven't been granted anything and we're NOT on a resource list,
* then we haven't got a reply yet and don't have a known disposition.
* This happens whenever a lock enqueue is the request that triggers
* recovery.
*/
if (lock->l_granted_mode == lock->l_req_mode)
flags = LDLM_FL_REPLAY | LDLM_FL_BLOCK_GRANTED;
else if (lock->l_granted_mode)
flags = LDLM_FL_REPLAY | LDLM_FL_BLOCK_CONV;
else if (!list_empty(&lock->l_res_link))
flags = LDLM_FL_REPLAY | LDLM_FL_BLOCK_WAIT;
else
flags = LDLM_FL_REPLAY;
req = ptlrpc_request_alloc_pack(imp, &RQF_LDLM_ENQUEUE,
LUSTRE_DLM_VERSION, LDLM_ENQUEUE);
if (req == NULL)
return -ENOMEM;
/* We're part of recovery, so don't wait for it. */
req->rq_send_state = LUSTRE_IMP_REPLAY_LOCKS;
body = req_capsule_client_get(&req->rq_pill, &RMF_DLM_REQ);
ldlm_lock2desc(lock, &body->lock_desc);
body->lock_flags = ldlm_flags_to_wire(flags);
ldlm_lock2handle(lock, &body->lock_handle[0]);
if (lock->l_lvb_len > 0)
req_capsule_extend(&req->rq_pill, &RQF_LDLM_ENQUEUE_LVB);
req_capsule_set_size(&req->rq_pill, &RMF_DLM_LVB, RCL_SERVER,
lock->l_lvb_len);
ptlrpc_request_set_replen(req);
/* notify the server we've replayed all requests.
* also, we mark the request to be put on a dedicated
* queue to be processed after all request replayes.
* bug 6063 */
lustre_msg_set_flags(req->rq_reqmsg, MSG_REQ_REPLAY_DONE);
LDLM_DEBUG(lock, "replaying lock:");
atomic_inc(&req->rq_import->imp_replay_inflight);
CLASSERT(sizeof(*aa) <= sizeof(req->rq_async_args));
aa = ptlrpc_req_async_args(req);
aa->lock_handle = body->lock_handle[0];
req->rq_interpret_reply = (ptlrpc_interpterer_t)replay_lock_interpret;
ptlrpcd_add_req(req, PDL_POLICY_LOCAL, -1);
return 0;
}
/**
* Cancel as many unused locks as possible before replay. since we are
* in recovery, we can't wait for any outstanding RPCs to send any RPC
* to the server.
*
* Called only in recovery before replaying locks. there is no need to
* replay locks that are unused. since the clients may hold thousands of
* cached unused locks, dropping the unused locks can greatly reduce the
* load on the servers at recovery time.
*/
static void ldlm_cancel_unused_locks_for_replay(struct ldlm_namespace *ns)
{
int canceled;
LIST_HEAD(cancels);
CDEBUG(D_DLMTRACE, "Dropping as many unused locks as possible before replay for namespace %s (%d)\n",
ldlm_ns_name(ns), ns->ns_nr_unused);
/* We don't need to care whether or not LRU resize is enabled
* because the LDLM_CANCEL_NO_WAIT policy doesn't use the
* count parameter */
canceled = ldlm_cancel_lru_local(ns, &cancels, ns->ns_nr_unused, 0,
LCF_LOCAL, LDLM_CANCEL_NO_WAIT);
CDEBUG(D_DLMTRACE, "Canceled %d unused locks from namespace %s\n",
canceled, ldlm_ns_name(ns));
}
int ldlm_replay_locks(struct obd_import *imp)
{
struct ldlm_namespace *ns = imp->imp_obd->obd_namespace;
LIST_HEAD(list);
struct ldlm_lock *lock, *next;
int rc = 0;
LASSERT(atomic_read(&imp->imp_replay_inflight) == 0);
/* don't replay locks if import failed recovery */
if (imp->imp_vbr_failed)
return 0;
/* ensure this doesn't fall to 0 before all have been queued */
atomic_inc(&imp->imp_replay_inflight);
if (ldlm_cancel_unused_locks_before_replay)
ldlm_cancel_unused_locks_for_replay(ns);
ldlm_namespace_foreach(ns, ldlm_chain_lock_for_replay, &list);
list_for_each_entry_safe(lock, next, &list, l_pending_chain) {
list_del_init(&lock->l_pending_chain);
if (rc) {
LDLM_LOCK_RELEASE(lock);
continue; /* or try to do the rest? */
}
rc = replay_one_lock(imp, lock);
LDLM_LOCK_RELEASE(lock);
}
atomic_dec(&imp->imp_replay_inflight);
return rc;
}
EXPORT_SYMBOL(ldlm_replay_locks);