freebsd-dev/sys/geom/geom_io.c
Luigi Rizzo 6231f75bcf As discussed in the devsummit, introduce two fields in the
struct bio to store classification information, and a hook
for classifier functions that can be called by g_io_request().

This code is from Fabio Checconi as part of his GSOC work.
2009-06-11 09:55:26 +00:00

782 lines
19 KiB
C

/*-
* Copyright (c) 2002 Poul-Henning Kamp
* Copyright (c) 2002 Networks Associates Technology, Inc.
* All rights reserved.
*
* This software was developed for the FreeBSD Project by Poul-Henning Kamp
* and NAI Labs, the Security Research Division of Network Associates, Inc.
* under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the
* DARPA CHATS research program.
*
* 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, 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.
* 3. The names of the authors may not be used to endorse or promote
* products derived from this software without specific prior written
* permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``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 OR CONTRIBUTORS 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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/bio.h>
#include <sys/ktr.h>
#include <sys/proc.h>
#include <sys/stack.h>
#include <sys/errno.h>
#include <geom/geom.h>
#include <geom/geom_int.h>
#include <sys/devicestat.h>
#include <vm/uma.h>
static struct g_bioq g_bio_run_down;
static struct g_bioq g_bio_run_up;
static struct g_bioq g_bio_run_task;
static u_int pace;
static uma_zone_t biozone;
/*
* The head of the list of classifiers used in g_io_request.
* Use g_register_classifier() and g_unregister_classifier()
* to add/remove entries to the list.
* Classifiers are invoked in registration order.
*/
static TAILQ_HEAD(g_classifier_tailq, g_classifier_hook)
g_classifier_tailq = TAILQ_HEAD_INITIALIZER(g_classifier_tailq);
#include <machine/atomic.h>
static void
g_bioq_lock(struct g_bioq *bq)
{
mtx_lock(&bq->bio_queue_lock);
}
static void
g_bioq_unlock(struct g_bioq *bq)
{
mtx_unlock(&bq->bio_queue_lock);
}
#if 0
static void
g_bioq_destroy(struct g_bioq *bq)
{
mtx_destroy(&bq->bio_queue_lock);
}
#endif
static void
g_bioq_init(struct g_bioq *bq)
{
TAILQ_INIT(&bq->bio_queue);
mtx_init(&bq->bio_queue_lock, "bio queue", NULL, MTX_DEF);
}
static struct bio *
g_bioq_first(struct g_bioq *bq)
{
struct bio *bp;
bp = TAILQ_FIRST(&bq->bio_queue);
if (bp != NULL) {
KASSERT((bp->bio_flags & BIO_ONQUEUE),
("Bio not on queue bp=%p target %p", bp, bq));
bp->bio_flags &= ~BIO_ONQUEUE;
TAILQ_REMOVE(&bq->bio_queue, bp, bio_queue);
bq->bio_queue_length--;
}
return (bp);
}
struct bio *
g_new_bio(void)
{
struct bio *bp;
bp = uma_zalloc(biozone, M_NOWAIT | M_ZERO);
#ifdef KTR
if ((KTR_COMPILE & KTR_GEOM) && (ktr_mask & KTR_GEOM)) {
struct stack st;
CTR1(KTR_GEOM, "g_new_bio(): %p", bp);
stack_save(&st);
CTRSTACK(KTR_GEOM, &st, 3, 0);
}
#endif
return (bp);
}
struct bio *
g_alloc_bio(void)
{
struct bio *bp;
bp = uma_zalloc(biozone, M_WAITOK | M_ZERO);
#ifdef KTR
if ((KTR_COMPILE & KTR_GEOM) && (ktr_mask & KTR_GEOM)) {
struct stack st;
CTR1(KTR_GEOM, "g_alloc_bio(): %p", bp);
stack_save(&st);
CTRSTACK(KTR_GEOM, &st, 3, 0);
}
#endif
return (bp);
}
void
g_destroy_bio(struct bio *bp)
{
#ifdef KTR
if ((KTR_COMPILE & KTR_GEOM) && (ktr_mask & KTR_GEOM)) {
struct stack st;
CTR1(KTR_GEOM, "g_destroy_bio(): %p", bp);
stack_save(&st);
CTRSTACK(KTR_GEOM, &st, 3, 0);
}
#endif
uma_zfree(biozone, bp);
}
struct bio *
g_clone_bio(struct bio *bp)
{
struct bio *bp2;
bp2 = uma_zalloc(biozone, M_NOWAIT | M_ZERO);
if (bp2 != NULL) {
bp2->bio_parent = bp;
bp2->bio_cmd = bp->bio_cmd;
bp2->bio_length = bp->bio_length;
bp2->bio_offset = bp->bio_offset;
bp2->bio_data = bp->bio_data;
bp2->bio_attribute = bp->bio_attribute;
/* Inherit classification info from the parent */
bp2->bio_classifier1 = bp->bio_classifier1;
bp2->bio_classifier2 = bp->bio_classifier2;
bp->bio_children++;
}
#ifdef KTR
if ((KTR_COMPILE & KTR_GEOM) && (ktr_mask & KTR_GEOM)) {
struct stack st;
CTR2(KTR_GEOM, "g_clone_bio(%p): %p", bp, bp2);
stack_save(&st);
CTRSTACK(KTR_GEOM, &st, 3, 0);
}
#endif
return(bp2);
}
struct bio *
g_duplicate_bio(struct bio *bp)
{
struct bio *bp2;
bp2 = uma_zalloc(biozone, M_WAITOK | M_ZERO);
bp2->bio_parent = bp;
bp2->bio_cmd = bp->bio_cmd;
bp2->bio_length = bp->bio_length;
bp2->bio_offset = bp->bio_offset;
bp2->bio_data = bp->bio_data;
bp2->bio_attribute = bp->bio_attribute;
bp->bio_children++;
#ifdef KTR
if ((KTR_COMPILE & KTR_GEOM) && (ktr_mask & KTR_GEOM)) {
struct stack st;
CTR2(KTR_GEOM, "g_duplicate_bio(%p): %p", bp, bp2);
stack_save(&st);
CTRSTACK(KTR_GEOM, &st, 3, 0);
}
#endif
return(bp2);
}
void
g_io_init()
{
g_bioq_init(&g_bio_run_down);
g_bioq_init(&g_bio_run_up);
g_bioq_init(&g_bio_run_task);
biozone = uma_zcreate("g_bio", sizeof (struct bio),
NULL, NULL,
NULL, NULL,
0, 0);
}
int
g_io_getattr(const char *attr, struct g_consumer *cp, int *len, void *ptr)
{
struct bio *bp;
int error;
g_trace(G_T_BIO, "bio_getattr(%s)", attr);
bp = g_alloc_bio();
bp->bio_cmd = BIO_GETATTR;
bp->bio_done = NULL;
bp->bio_attribute = attr;
bp->bio_length = *len;
bp->bio_data = ptr;
g_io_request(bp, cp);
error = biowait(bp, "ggetattr");
*len = bp->bio_completed;
g_destroy_bio(bp);
return (error);
}
int
g_io_flush(struct g_consumer *cp)
{
struct bio *bp;
int error;
g_trace(G_T_BIO, "bio_flush(%s)", cp->provider->name);
bp = g_alloc_bio();
bp->bio_cmd = BIO_FLUSH;
bp->bio_done = NULL;
bp->bio_attribute = NULL;
bp->bio_offset = cp->provider->mediasize;
bp->bio_length = 0;
bp->bio_data = NULL;
g_io_request(bp, cp);
error = biowait(bp, "gflush");
g_destroy_bio(bp);
return (error);
}
static int
g_io_check(struct bio *bp)
{
struct g_consumer *cp;
struct g_provider *pp;
cp = bp->bio_from;
pp = bp->bio_to;
/* Fail if access counters dont allow the operation */
switch(bp->bio_cmd) {
case BIO_READ:
case BIO_GETATTR:
if (cp->acr == 0)
return (EPERM);
break;
case BIO_WRITE:
case BIO_DELETE:
case BIO_FLUSH:
if (cp->acw == 0)
return (EPERM);
break;
default:
return (EPERM);
}
/* if provider is marked for error, don't disturb. */
if (pp->error)
return (pp->error);
switch(bp->bio_cmd) {
case BIO_READ:
case BIO_WRITE:
case BIO_DELETE:
/* Zero sectorsize is a probably lack of media */
if (pp->sectorsize == 0)
return (ENXIO);
/* Reject I/O not on sector boundary */
if (bp->bio_offset % pp->sectorsize)
return (EINVAL);
/* Reject I/O not integral sector long */
if (bp->bio_length % pp->sectorsize)
return (EINVAL);
/* Reject requests before or past the end of media. */
if (bp->bio_offset < 0)
return (EIO);
if (bp->bio_offset > pp->mediasize)
return (EIO);
break;
default:
break;
}
return (0);
}
/*
* bio classification support.
*
* g_register_classifier() and g_unregister_classifier()
* are used to add/remove a classifier from the list.
* The list is protected using the g_bio_run_down lock,
* because the classifiers are called in this path.
*
* g_io_request() passes bio's that are not already classified
* (i.e. those with bio_classifier1 == NULL) to g_run_classifiers().
* Classifiers can store their result in the two fields
* bio_classifier1 and bio_classifier2.
* A classifier that updates one of the fields should
* return a non-zero value.
* If no classifier updates the field, g_run_classifiers() sets
* bio_classifier1 = BIO_NOTCLASSIFIED to avoid further calls.
*/
int
g_register_classifier(struct g_classifier_hook *hook)
{
g_bioq_lock(&g_bio_run_down);
TAILQ_INSERT_TAIL(&g_classifier_tailq, hook, link);
g_bioq_unlock(&g_bio_run_down);
return (0);
}
void
g_unregister_classifier(struct g_classifier_hook *hook)
{
struct g_classifier_hook *entry;
g_bioq_lock(&g_bio_run_down);
TAILQ_FOREACH(entry, &g_classifier_tailq, link) {
if (entry == hook) {
TAILQ_REMOVE(&g_classifier_tailq, hook, link);
break;
}
}
g_bioq_unlock(&g_bio_run_down);
}
static void
g_run_classifiers(struct bio *bp)
{
struct g_classifier_hook *hook;
int classified = 0;
TAILQ_FOREACH(hook, &g_classifier_tailq, link)
classified |= hook->func(hook->arg, bp);
if (!classified)
bp->bio_classifier1 = BIO_NOTCLASSIFIED;
}
void
g_io_request(struct bio *bp, struct g_consumer *cp)
{
struct g_provider *pp;
KASSERT(cp != NULL, ("NULL cp in g_io_request"));
KASSERT(bp != NULL, ("NULL bp in g_io_request"));
pp = cp->provider;
KASSERT(pp != NULL, ("consumer not attached in g_io_request"));
#ifdef DIAGNOSTIC
KASSERT(bp->bio_driver1 == NULL,
("bio_driver1 used by the consumer (geom %s)", cp->geom->name));
KASSERT(bp->bio_driver2 == NULL,
("bio_driver2 used by the consumer (geom %s)", cp->geom->name));
KASSERT(bp->bio_pflags == 0,
("bio_pflags used by the consumer (geom %s)", cp->geom->name));
/*
* Remember consumer's private fields, so we can detect if they were
* modified by the provider.
*/
bp->_bio_caller1 = bp->bio_caller1;
bp->_bio_caller2 = bp->bio_caller2;
bp->_bio_cflags = bp->bio_cflags;
#endif
if (bp->bio_cmd & (BIO_READ|BIO_WRITE|BIO_GETATTR)) {
KASSERT(bp->bio_data != NULL,
("NULL bp->data in g_io_request(cmd=%hhu)", bp->bio_cmd));
}
if (bp->bio_cmd & (BIO_DELETE|BIO_FLUSH)) {
KASSERT(bp->bio_data == NULL,
("non-NULL bp->data in g_io_request(cmd=%hhu)",
bp->bio_cmd));
}
if (bp->bio_cmd & (BIO_READ|BIO_WRITE|BIO_DELETE)) {
KASSERT(bp->bio_offset % cp->provider->sectorsize == 0,
("wrong offset %jd for sectorsize %u",
bp->bio_offset, cp->provider->sectorsize));
KASSERT(bp->bio_length % cp->provider->sectorsize == 0,
("wrong length %jd for sectorsize %u",
bp->bio_length, cp->provider->sectorsize));
}
g_trace(G_T_BIO, "bio_request(%p) from %p(%s) to %p(%s) cmd %d",
bp, cp, cp->geom->name, pp, pp->name, bp->bio_cmd);
bp->bio_from = cp;
bp->bio_to = pp;
bp->bio_error = 0;
bp->bio_completed = 0;
KASSERT(!(bp->bio_flags & BIO_ONQUEUE),
("Bio already on queue bp=%p", bp));
bp->bio_flags |= BIO_ONQUEUE;
binuptime(&bp->bio_t0);
/*
* The statistics collection is lockless, as such, but we
* can not update one instance of the statistics from more
* than one thread at a time, so grab the lock first.
*
* We also use the lock to protect the list of classifiers.
*/
g_bioq_lock(&g_bio_run_down);
if (!TAILQ_EMPTY(&g_classifier_tailq) && !bp->bio_classifier1)
g_run_classifiers(bp);
if (g_collectstats & 1)
devstat_start_transaction(pp->stat, &bp->bio_t0);
if (g_collectstats & 2)
devstat_start_transaction(cp->stat, &bp->bio_t0);
pp->nstart++;
cp->nstart++;
TAILQ_INSERT_TAIL(&g_bio_run_down.bio_queue, bp, bio_queue);
g_bio_run_down.bio_queue_length++;
g_bioq_unlock(&g_bio_run_down);
/* Pass it on down. */
wakeup(&g_wait_down);
}
void
g_io_deliver(struct bio *bp, int error)
{
struct g_consumer *cp;
struct g_provider *pp;
KASSERT(bp != NULL, ("NULL bp in g_io_deliver"));
pp = bp->bio_to;
KASSERT(pp != NULL, ("NULL bio_to in g_io_deliver"));
#ifdef DIAGNOSTIC
KASSERT(bp->bio_caller1 == bp->_bio_caller1,
("bio_caller1 used by the provider %s", pp->name));
KASSERT(bp->bio_caller2 == bp->_bio_caller2,
("bio_caller2 used by the provider %s", pp->name));
KASSERT(bp->bio_cflags == bp->_bio_cflags,
("bio_cflags used by the provider %s", pp->name));
#endif
cp = bp->bio_from;
if (cp == NULL) {
bp->bio_error = error;
bp->bio_done(bp);
return;
}
KASSERT(cp != NULL, ("NULL bio_from in g_io_deliver"));
KASSERT(cp->geom != NULL, ("NULL bio_from->geom in g_io_deliver"));
KASSERT(bp->bio_completed >= 0, ("bio_completed can't be less than 0"));
KASSERT(bp->bio_completed <= bp->bio_length,
("bio_completed can't be greater than bio_length"));
g_trace(G_T_BIO,
"g_io_deliver(%p) from %p(%s) to %p(%s) cmd %d error %d off %jd len %jd",
bp, cp, cp->geom->name, pp, pp->name, bp->bio_cmd, error,
(intmax_t)bp->bio_offset, (intmax_t)bp->bio_length);
KASSERT(!(bp->bio_flags & BIO_ONQUEUE),
("Bio already on queue bp=%p", bp));
/*
* XXX: next two doesn't belong here
*/
bp->bio_bcount = bp->bio_length;
bp->bio_resid = bp->bio_bcount - bp->bio_completed;
/*
* The statistics collection is lockless, as such, but we
* can not update one instance of the statistics from more
* than one thread at a time, so grab the lock first.
*/
g_bioq_lock(&g_bio_run_up);
if (g_collectstats & 1)
devstat_end_transaction_bio(pp->stat, bp);
if (g_collectstats & 2)
devstat_end_transaction_bio(cp->stat, bp);
cp->nend++;
pp->nend++;
if (error != ENOMEM) {
bp->bio_error = error;
TAILQ_INSERT_TAIL(&g_bio_run_up.bio_queue, bp, bio_queue);
bp->bio_flags |= BIO_ONQUEUE;
g_bio_run_up.bio_queue_length++;
g_bioq_unlock(&g_bio_run_up);
wakeup(&g_wait_up);
return;
}
g_bioq_unlock(&g_bio_run_up);
if (bootverbose)
printf("ENOMEM %p on %p(%s)\n", bp, pp, pp->name);
bp->bio_children = 0;
bp->bio_inbed = 0;
g_io_request(bp, cp);
pace++;
return;
}
void
g_io_schedule_down(struct thread *tp __unused)
{
struct bio *bp;
off_t excess;
int error;
for(;;) {
g_bioq_lock(&g_bio_run_down);
bp = g_bioq_first(&g_bio_run_down);
if (bp == NULL) {
CTR0(KTR_GEOM, "g_down going to sleep");
msleep(&g_wait_down, &g_bio_run_down.bio_queue_lock,
PRIBIO | PDROP, "-", hz/10);
continue;
}
CTR0(KTR_GEOM, "g_down has work to do");
g_bioq_unlock(&g_bio_run_down);
if (pace > 0) {
CTR1(KTR_GEOM, "g_down pacing self (pace %d)", pace);
pause("g_down", hz/10);
pace--;
}
error = g_io_check(bp);
if (error) {
CTR3(KTR_GEOM, "g_down g_io_check on bp %p provider "
"%s returned %d", bp, bp->bio_to->name, error);
g_io_deliver(bp, error);
continue;
}
CTR2(KTR_GEOM, "g_down processing bp %p provider %s", bp,
bp->bio_to->name);
switch (bp->bio_cmd) {
case BIO_READ:
case BIO_WRITE:
case BIO_DELETE:
/* Truncate requests to the end of providers media. */
/*
* XXX: What if we truncate because of offset being
* bad, not length?
*/
excess = bp->bio_offset + bp->bio_length;
if (excess > bp->bio_to->mediasize) {
excess -= bp->bio_to->mediasize;
bp->bio_length -= excess;
if (excess > 0)
CTR3(KTR_GEOM, "g_down truncated bio "
"%p provider %s by %d", bp,
bp->bio_to->name, excess);
}
/* Deliver zero length transfers right here. */
if (bp->bio_length == 0) {
g_io_deliver(bp, 0);
CTR2(KTR_GEOM, "g_down terminated 0-length "
"bp %p provider %s", bp, bp->bio_to->name);
continue;
}
break;
default:
break;
}
THREAD_NO_SLEEPING();
CTR4(KTR_GEOM, "g_down starting bp %p provider %s off %ld "
"len %ld", bp, bp->bio_to->name, bp->bio_offset,
bp->bio_length);
bp->bio_to->geom->start(bp);
THREAD_SLEEPING_OK();
}
}
void
bio_taskqueue(struct bio *bp, bio_task_t *func, void *arg)
{
bp->bio_task = func;
bp->bio_task_arg = arg;
/*
* The taskqueue is actually just a second queue off the "up"
* queue, so we use the same lock.
*/
g_bioq_lock(&g_bio_run_up);
KASSERT(!(bp->bio_flags & BIO_ONQUEUE),
("Bio already on queue bp=%p target taskq", bp));
bp->bio_flags |= BIO_ONQUEUE;
TAILQ_INSERT_TAIL(&g_bio_run_task.bio_queue, bp, bio_queue);
g_bio_run_task.bio_queue_length++;
wakeup(&g_wait_up);
g_bioq_unlock(&g_bio_run_up);
}
void
g_io_schedule_up(struct thread *tp __unused)
{
struct bio *bp;
for(;;) {
g_bioq_lock(&g_bio_run_up);
bp = g_bioq_first(&g_bio_run_task);
if (bp != NULL) {
g_bioq_unlock(&g_bio_run_up);
THREAD_NO_SLEEPING();
CTR1(KTR_GEOM, "g_up processing task bp %p", bp);
bp->bio_task(bp->bio_task_arg);
THREAD_SLEEPING_OK();
continue;
}
bp = g_bioq_first(&g_bio_run_up);
if (bp != NULL) {
g_bioq_unlock(&g_bio_run_up);
THREAD_NO_SLEEPING();
CTR4(KTR_GEOM, "g_up biodone bp %p provider %s off "
"%jd len %ld", bp, bp->bio_to->name,
bp->bio_offset, bp->bio_length);
biodone(bp);
THREAD_SLEEPING_OK();
continue;
}
CTR0(KTR_GEOM, "g_up going to sleep");
msleep(&g_wait_up, &g_bio_run_up.bio_queue_lock,
PRIBIO | PDROP, "-", hz/10);
}
}
void *
g_read_data(struct g_consumer *cp, off_t offset, off_t length, int *error)
{
struct bio *bp;
void *ptr;
int errorc;
KASSERT(length > 0 && length >= cp->provider->sectorsize &&
length <= MAXPHYS, ("g_read_data(): invalid length %jd",
(intmax_t)length));
bp = g_alloc_bio();
bp->bio_cmd = BIO_READ;
bp->bio_done = NULL;
bp->bio_offset = offset;
bp->bio_length = length;
ptr = g_malloc(length, M_WAITOK);
bp->bio_data = ptr;
g_io_request(bp, cp);
errorc = biowait(bp, "gread");
if (error != NULL)
*error = errorc;
g_destroy_bio(bp);
if (errorc) {
g_free(ptr);
ptr = NULL;
}
return (ptr);
}
int
g_write_data(struct g_consumer *cp, off_t offset, void *ptr, off_t length)
{
struct bio *bp;
int error;
KASSERT(length > 0 && length >= cp->provider->sectorsize &&
length <= MAXPHYS, ("g_write_data(): invalid length %jd",
(intmax_t)length));
bp = g_alloc_bio();
bp->bio_cmd = BIO_WRITE;
bp->bio_done = NULL;
bp->bio_offset = offset;
bp->bio_length = length;
bp->bio_data = ptr;
g_io_request(bp, cp);
error = biowait(bp, "gwrite");
g_destroy_bio(bp);
return (error);
}
int
g_delete_data(struct g_consumer *cp, off_t offset, off_t length)
{
struct bio *bp;
int error;
KASSERT(length > 0 && length >= cp->provider->sectorsize,
("g_delete_data(): invalid length %jd", (intmax_t)length));
bp = g_alloc_bio();
bp->bio_cmd = BIO_DELETE;
bp->bio_done = NULL;
bp->bio_offset = offset;
bp->bio_length = length;
bp->bio_data = NULL;
g_io_request(bp, cp);
error = biowait(bp, "gdelete");
g_destroy_bio(bp);
return (error);
}
void
g_print_bio(struct bio *bp)
{
const char *pname, *cmd = NULL;
if (bp->bio_to != NULL)
pname = bp->bio_to->name;
else
pname = "[unknown]";
switch (bp->bio_cmd) {
case BIO_GETATTR:
cmd = "GETATTR";
printf("%s[%s(attr=%s)]", pname, cmd, bp->bio_attribute);
return;
case BIO_FLUSH:
cmd = "FLUSH";
printf("%s[%s]", pname, cmd);
return;
case BIO_READ:
cmd = "READ";
case BIO_WRITE:
if (cmd == NULL)
cmd = "WRITE";
case BIO_DELETE:
if (cmd == NULL)
cmd = "DELETE";
printf("%s[%s(offset=%jd, length=%jd)]", pname, cmd,
(intmax_t)bp->bio_offset, (intmax_t)bp->bio_length);
return;
default:
cmd = "UNKNOWN";
printf("%s[%s()]", pname, cmd);
return;
}
/* NOTREACHED */
}