504 lines
10 KiB
C
504 lines
10 KiB
C
/*
|
|
* Copyright (c) 2002, Jeffrey Roberson <jeff@freebsd.org>
|
|
* All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice unmodified, this list of conditions, and the following
|
|
* disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
|
|
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
|
|
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
|
|
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
|
|
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
|
|
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
|
|
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
|
|
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
|
|
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
|
|
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
|
*
|
|
* $FreeBSD$
|
|
*
|
|
*/
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/systm.h>
|
|
#include <sys/kernel.h>
|
|
#include <sys/kthread.h>
|
|
#include <sys/lock.h>
|
|
#include <sys/mutex.h>
|
|
#include <sys/namei.h>
|
|
#include <sys/proc.h>
|
|
#include <sys/vnode.h>
|
|
#include <sys/alq.h>
|
|
#include <sys/malloc.h>
|
|
#include <sys/unistd.h>
|
|
#include <sys/fcntl.h>
|
|
#include <sys/eventhandler.h>
|
|
|
|
/* Async. Logging Queue */
|
|
struct alq {
|
|
int aq_entmax; /* Max entries */
|
|
int aq_entlen; /* Entry length */
|
|
char *aq_entbuf; /* Buffer for stored entries */
|
|
int aq_flags; /* Queue flags */
|
|
struct mtx aq_mtx; /* Queue lock */
|
|
struct vnode *aq_vp; /* Open vnode handle */
|
|
struct ucred *aq_cred; /* Credentials of the opening thread */
|
|
struct ale *aq_first; /* First ent */
|
|
struct ale *aq_entfree; /* First free ent */
|
|
struct ale *aq_entvalid; /* First ent valid for writing */
|
|
LIST_ENTRY(alq) aq_act; /* List of active queues */
|
|
LIST_ENTRY(alq) aq_link; /* List of all queues */
|
|
};
|
|
|
|
#define AQ_WANTED 0x0001 /* Wakeup sleeper when io is done */
|
|
#define AQ_ACTIVE 0x0002 /* on the active list */
|
|
#define AQ_FLUSHING 0x0004 /* doing IO */
|
|
#define AQ_SHUTDOWN 0x0008 /* Queue no longer valid */
|
|
|
|
#define ALQ_LOCK(alq) mtx_lock_spin(&(alq)->aq_mtx)
|
|
#define ALQ_UNLOCK(alq) mtx_unlock_spin(&(alq)->aq_mtx)
|
|
|
|
static MALLOC_DEFINE(M_ALD, "ALD", "ALD");
|
|
|
|
/*
|
|
* The ald_mtx protects the ald_queues list and the ald_active list.
|
|
*/
|
|
static struct mtx ald_mtx;
|
|
static LIST_HEAD(, alq) ald_queues;
|
|
static LIST_HEAD(, alq) ald_active;
|
|
static int ald_shutingdown = 0;
|
|
struct thread *ald_thread;
|
|
static struct proc *ald_proc;
|
|
|
|
#define ALD_LOCK() mtx_lock(&ald_mtx)
|
|
#define ALD_UNLOCK() mtx_unlock(&ald_mtx)
|
|
|
|
/* Daemon functions */
|
|
static int ald_add(struct alq *);
|
|
static int ald_rem(struct alq *);
|
|
static void ald_startup(void *);
|
|
static void ald_daemon(void);
|
|
static void ald_shutdown(void *, int);
|
|
static void ald_activate(struct alq *);
|
|
static void ald_deactivate(struct alq *);
|
|
|
|
/* Internal queue functions */
|
|
static void alq_shutdown(struct alq *);
|
|
static int alq_doio(struct alq *);
|
|
|
|
|
|
/*
|
|
* Add a new queue to the global list. Fail if we're shutting down.
|
|
*/
|
|
static int
|
|
ald_add(struct alq *alq)
|
|
{
|
|
int error;
|
|
|
|
error = 0;
|
|
|
|
ALD_LOCK();
|
|
if (ald_shutingdown) {
|
|
error = EBUSY;
|
|
goto done;
|
|
}
|
|
LIST_INSERT_HEAD(&ald_queues, alq, aq_link);
|
|
done:
|
|
ALD_UNLOCK();
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Remove a queue from the global list unless we're shutting down. If so,
|
|
* the ald will take care of cleaning up it's resources.
|
|
*/
|
|
static int
|
|
ald_rem(struct alq *alq)
|
|
{
|
|
int error;
|
|
|
|
error = 0;
|
|
|
|
ALD_LOCK();
|
|
if (ald_shutingdown) {
|
|
error = EBUSY;
|
|
goto done;
|
|
}
|
|
LIST_REMOVE(alq, aq_link);
|
|
done:
|
|
ALD_UNLOCK();
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Put a queue on the active list. This will schedule it for writing.
|
|
*/
|
|
static void
|
|
ald_activate(struct alq *alq)
|
|
{
|
|
LIST_INSERT_HEAD(&ald_active, alq, aq_act);
|
|
wakeup(&ald_active);
|
|
}
|
|
|
|
static void
|
|
ald_deactivate(struct alq *alq)
|
|
{
|
|
LIST_REMOVE(alq, aq_act);
|
|
alq->aq_flags &= ~AQ_ACTIVE;
|
|
}
|
|
|
|
static void
|
|
ald_startup(void *unused)
|
|
{
|
|
mtx_init(&ald_mtx, "ALDmtx", NULL, MTX_DEF|MTX_QUIET);
|
|
LIST_INIT(&ald_queues);
|
|
LIST_INIT(&ald_active);
|
|
}
|
|
|
|
static void
|
|
ald_daemon(void)
|
|
{
|
|
int needwakeup;
|
|
struct alq *alq;
|
|
|
|
mtx_lock(&Giant);
|
|
|
|
ald_thread = FIRST_THREAD_IN_PROC(ald_proc);
|
|
|
|
EVENTHANDLER_REGISTER(shutdown_pre_sync, ald_shutdown, NULL,
|
|
SHUTDOWN_PRI_FIRST);
|
|
|
|
ALD_LOCK();
|
|
|
|
for (;;) {
|
|
while ((alq = LIST_FIRST(&ald_active)) == NULL)
|
|
msleep(&ald_active, &ald_mtx, PWAIT, "aldslp", 0);
|
|
|
|
ALQ_LOCK(alq);
|
|
ald_deactivate(alq);
|
|
ALD_UNLOCK();
|
|
needwakeup = alq_doio(alq);
|
|
ALQ_UNLOCK(alq);
|
|
if (needwakeup)
|
|
wakeup(alq);
|
|
ALD_LOCK();
|
|
}
|
|
}
|
|
|
|
static void
|
|
ald_shutdown(void *arg, int howto)
|
|
{
|
|
struct alq *alq;
|
|
|
|
ALD_LOCK();
|
|
ald_shutingdown = 1;
|
|
|
|
while ((alq = LIST_FIRST(&ald_queues)) != NULL) {
|
|
LIST_REMOVE(alq, aq_link);
|
|
ALD_UNLOCK();
|
|
alq_shutdown(alq);
|
|
ALD_LOCK();
|
|
}
|
|
ALD_UNLOCK();
|
|
}
|
|
|
|
static void
|
|
alq_shutdown(struct alq *alq)
|
|
{
|
|
ALQ_LOCK(alq);
|
|
|
|
/* Stop any new writers. */
|
|
alq->aq_flags |= AQ_SHUTDOWN;
|
|
|
|
/* Drain IO */
|
|
while (alq->aq_flags & (AQ_FLUSHING|AQ_ACTIVE)) {
|
|
alq->aq_flags |= AQ_WANTED;
|
|
ALQ_UNLOCK(alq);
|
|
tsleep(alq, PWAIT, "aldclose", 0);
|
|
ALQ_LOCK(alq);
|
|
}
|
|
ALQ_UNLOCK(alq);
|
|
|
|
vn_close(alq->aq_vp, FWRITE, alq->aq_cred,
|
|
curthread);
|
|
crfree(alq->aq_cred);
|
|
}
|
|
|
|
/*
|
|
* Flush all pending data to disk. This operation will block.
|
|
*/
|
|
static int
|
|
alq_doio(struct alq *alq)
|
|
{
|
|
struct thread *td;
|
|
struct mount *mp;
|
|
struct vnode *vp;
|
|
struct uio auio;
|
|
struct iovec aiov[2];
|
|
struct ale *ale;
|
|
struct ale *alstart;
|
|
int totlen;
|
|
int iov;
|
|
|
|
vp = alq->aq_vp;
|
|
td = curthread;
|
|
totlen = 0;
|
|
iov = 0;
|
|
|
|
alstart = ale = alq->aq_entvalid;
|
|
alq->aq_entvalid = NULL;
|
|
|
|
bzero(&aiov, sizeof(aiov));
|
|
bzero(&auio, sizeof(auio));
|
|
|
|
do {
|
|
if (aiov[iov].iov_base == NULL)
|
|
aiov[iov].iov_base = ale->ae_data;
|
|
aiov[iov].iov_len += alq->aq_entlen;
|
|
totlen += alq->aq_entlen;
|
|
/* Check to see if we're wrapping the buffer */
|
|
if (ale->ae_data + alq->aq_entlen != ale->ae_next->ae_data)
|
|
iov++;
|
|
ale->ae_flags &= ~AE_VALID;
|
|
ale = ale->ae_next;
|
|
} while (ale->ae_flags & AE_VALID);
|
|
|
|
alq->aq_flags |= AQ_FLUSHING;
|
|
ALQ_UNLOCK(alq);
|
|
|
|
if (iov == 2 || aiov[iov].iov_base == NULL)
|
|
iov--;
|
|
|
|
auio.uio_iov = &aiov[0];
|
|
auio.uio_offset = 0;
|
|
auio.uio_segflg = UIO_SYSSPACE;
|
|
auio.uio_rw = UIO_WRITE;
|
|
auio.uio_iovcnt = iov + 1;
|
|
auio.uio_resid = totlen;
|
|
auio.uio_td = td;
|
|
|
|
/*
|
|
* Do all of the junk required to write now.
|
|
*/
|
|
vn_start_write(vp, &mp, V_WAIT);
|
|
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td);
|
|
VOP_LEASE(vp, td, alq->aq_cred, LEASE_WRITE);
|
|
/* XXX error ignored */
|
|
VOP_WRITE(vp, &auio, IO_UNIT | IO_APPEND, alq->aq_cred);
|
|
VOP_UNLOCK(vp, 0, td);
|
|
vn_finished_write(mp);
|
|
|
|
ALQ_LOCK(alq);
|
|
alq->aq_flags &= ~AQ_FLUSHING;
|
|
|
|
if (alq->aq_entfree == NULL)
|
|
alq->aq_entfree = alstart;
|
|
|
|
if (alq->aq_flags & AQ_WANTED) {
|
|
alq->aq_flags &= ~AQ_WANTED;
|
|
return (1);
|
|
}
|
|
|
|
return(0);
|
|
}
|
|
|
|
static struct kproc_desc ald_kp = {
|
|
"ALQ Daemon",
|
|
ald_daemon,
|
|
&ald_proc
|
|
};
|
|
|
|
SYSINIT(aldthread, SI_SUB_KTHREAD_IDLE, SI_ORDER_ANY, kproc_start, &ald_kp)
|
|
SYSINIT(ald, SI_SUB_LOCK, SI_ORDER_ANY, ald_startup, NULL)
|
|
|
|
|
|
/* User visible queue functions */
|
|
|
|
/*
|
|
* Create the queue data structure, allocate the buffer, and open the file.
|
|
*/
|
|
int
|
|
alq_open(struct alq **alqp, const char *file, int size, int count)
|
|
{
|
|
struct thread *td;
|
|
struct nameidata nd;
|
|
struct ale *ale;
|
|
struct ale *alp;
|
|
struct alq *alq;
|
|
char *bufp;
|
|
int flags;
|
|
int error;
|
|
int i;
|
|
|
|
*alqp = NULL;
|
|
td = curthread;
|
|
|
|
NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, file, td);
|
|
flags = FWRITE | O_NOFOLLOW | O_CREAT;
|
|
|
|
error = vn_open(&nd, &flags, 0);
|
|
if (error)
|
|
return (error);
|
|
|
|
NDFREE(&nd, NDF_ONLY_PNBUF);
|
|
/* We just unlock so we hold a reference */
|
|
VOP_UNLOCK(nd.ni_vp, 0, td);
|
|
|
|
alq = malloc(sizeof(*alq), M_ALD, M_ZERO);
|
|
alq->aq_entbuf = malloc(count * size, M_ALD, M_ZERO);
|
|
alq->aq_first = malloc(sizeof(*ale) * count, M_ALD, M_ZERO);
|
|
alq->aq_vp = nd.ni_vp;
|
|
alq->aq_cred = crhold(td->td_ucred);
|
|
alq->aq_entmax = count;
|
|
alq->aq_entlen = size;
|
|
alq->aq_entfree = alq->aq_first;
|
|
|
|
mtx_init(&alq->aq_mtx, "ALD Queue", NULL, MTX_SPIN|MTX_QUIET);
|
|
|
|
bufp = alq->aq_entbuf;
|
|
ale = alq->aq_first;
|
|
alp = NULL;
|
|
|
|
/* Match up entries with buffers */
|
|
for (i = 0; i < count; i++) {
|
|
if (alp)
|
|
alp->ae_next = ale;
|
|
ale->ae_data = bufp;
|
|
alp = ale;
|
|
ale++;
|
|
bufp += size;
|
|
}
|
|
|
|
alp->ae_next = alq->aq_first;
|
|
|
|
if ((error = ald_add(alq)) != 0)
|
|
return (error);
|
|
*alqp = alq;
|
|
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Copy a new entry into the queue. If the operation would block either
|
|
* wait or return an error depending on the value of waitok.
|
|
*/
|
|
int
|
|
alq_write(struct alq *alq, void *data, int waitok)
|
|
{
|
|
struct ale *ale;
|
|
|
|
if ((ale = alq_get(alq, waitok)) == NULL)
|
|
return (EWOULDBLOCK);
|
|
|
|
bcopy(data, ale->ae_data, alq->aq_entlen);
|
|
alq_post(alq, ale);
|
|
|
|
return (0);
|
|
}
|
|
|
|
struct ale *
|
|
alq_get(struct alq *alq, int waitok)
|
|
{
|
|
struct ale *ale;
|
|
struct ale *aln;
|
|
|
|
ale = NULL;
|
|
|
|
ALQ_LOCK(alq);
|
|
|
|
/* Loop until we get an entry or we're shutting down */
|
|
while ((alq->aq_flags & AQ_SHUTDOWN) == 0 &&
|
|
(ale = alq->aq_entfree) == NULL &&
|
|
(waitok & ALQ_WAITOK)) {
|
|
alq->aq_flags |= AQ_WANTED;
|
|
ALQ_UNLOCK(alq);
|
|
tsleep(alq, PWAIT, "alqget", 0);
|
|
ALQ_LOCK(alq);
|
|
}
|
|
|
|
if (ale != NULL) {
|
|
aln = ale->ae_next;
|
|
if ((aln->ae_flags & AE_VALID) == 0)
|
|
alq->aq_entfree = aln;
|
|
} else
|
|
ALQ_UNLOCK(alq);
|
|
|
|
|
|
return (ale);
|
|
}
|
|
|
|
void
|
|
alq_post(struct alq *alq, struct ale *ale)
|
|
{
|
|
int activate;
|
|
|
|
ale->ae_flags |= AE_VALID;
|
|
|
|
if (alq->aq_entvalid == NULL)
|
|
alq->aq_entvalid = ale;
|
|
|
|
if ((alq->aq_flags & AQ_ACTIVE) == 0) {
|
|
alq->aq_flags |= AQ_ACTIVE;
|
|
activate = 1;
|
|
} else
|
|
activate = 0;
|
|
|
|
ALQ_UNLOCK(alq);
|
|
if (activate) {
|
|
ALD_LOCK();
|
|
ald_activate(alq);
|
|
ALD_UNLOCK();
|
|
}
|
|
}
|
|
|
|
void
|
|
alq_flush(struct alq *alq)
|
|
{
|
|
int needwakeup = 0;
|
|
|
|
ALD_LOCK();
|
|
ALQ_LOCK(alq);
|
|
if (alq->aq_flags & AQ_ACTIVE) {
|
|
ald_deactivate(alq);
|
|
ALD_UNLOCK();
|
|
needwakeup = alq_doio(alq);
|
|
} else
|
|
ALD_UNLOCK();
|
|
ALQ_UNLOCK(alq);
|
|
|
|
if (needwakeup)
|
|
wakeup(alq);
|
|
}
|
|
|
|
/*
|
|
* Flush remaining data, close the file and free all resources.
|
|
*/
|
|
void
|
|
alq_close(struct alq *alq)
|
|
{
|
|
/*
|
|
* If we're already shuting down someone else will flush and close
|
|
* the vnode.
|
|
*/
|
|
if (ald_rem(alq) != 0)
|
|
return;
|
|
|
|
/*
|
|
* Drain all pending IO.
|
|
*/
|
|
alq_shutdown(alq);
|
|
|
|
mtx_destroy(&alq->aq_mtx);
|
|
free(alq->aq_first, M_ALD);
|
|
free(alq->aq_entbuf, M_ALD);
|
|
free(alq, M_ALD);
|
|
}
|