freebsd-dev/sys/dev/cfi/cfi_disk.c
Brooks Davis f43581345b MFP4 217312, 222008, 222052, 222053, 222673, 231484, 231491, 231565, 570643
Rework the timeout code to use actual time rather than a DELAY() loop and
to use both typical and maximum to allow logging of timeout failures.
Also correct the erase timeout, it is specified in milliseconds not
microseconds like the other timeouts.  Do not invoke DELAY() between
status queries as this adds significant latency which in turn reduced
write performance substantially.

Sanity check timeout values from the hardware.

Implement support for buffered writes (only enabled on Intel/Sharp parts
for now).  This yields an order of magnitude speedup on the 64MB Intel
StrataFlash parts we use.

When making a copy of the block to modify, also keep a clean copy around
until we are ready to commit the block and use it to avoid unnecessary
erases.  In the non-buffer write case, also use it to avoid
unnecessary writes when the block has not been erased.  This yields a
significant speedup when doing things like zeroing a block.

Sponsored by:	DARPA, AFRL
Reviewed by:	imp (previous version)
2013-09-04 17:19:21 +00:00

360 lines
8.9 KiB
C

/*-
* Copyright (c) 2009 Sam Leffler, Errno Consulting
* Copyright (c) 2012-2013, SRI International
* All rights reserved.
*
* Portions of this software were developed by SRI International and the
* University of Cambridge Computer Laboratory under DARPA/AFRL contract
* (FA8750-10-C-0237) ("CTSRD"), as part of the DARPA CRASH research
* programme.
*
* 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.
*
* 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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/bio.h>
#include <sys/bus.h>
#include <sys/conf.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/module.h>
#include <sys/rman.h>
#include <sys/sysctl.h>
#include <sys/taskqueue.h>
#include <machine/bus.h>
#include <dev/cfi/cfi_var.h>
#include <geom/geom.h>
#include <geom/geom_disk.h>
struct cfi_disk_softc {
struct cfi_softc *parent;
struct disk *disk;
int flags;
#define CFI_DISK_OPEN 0x0001
struct bio_queue_head bioq; /* bio queue */
struct mtx qlock; /* bioq lock */
struct taskqueue *tq; /* private task queue for i/o request */
struct task iotask; /* i/o processing */
};
#define CFI_DISK_SECSIZE 512
#define CFI_DISK_MAXIOSIZE 65536
static int cfi_disk_detach(device_t);
static int cfi_disk_open(struct disk *);
static int cfi_disk_close(struct disk *);
static void cfi_io_proc(void *, int);
static int cfi_disk_getattr(struct bio *);
static void cfi_disk_strategy(struct bio *);
static int cfi_disk_ioctl(struct disk *, u_long, void *, int, struct thread *);
static int
cfi_disk_probe(device_t dev)
{
return 0;
}
static int
cfi_disk_attach(device_t dev)
{
struct cfi_disk_softc *sc = device_get_softc(dev);
sc->parent = device_get_softc(device_get_parent(dev));
/* validate interface width; assumed by other code */
if (sc->parent->sc_width != 1 &&
sc->parent->sc_width != 2 &&
sc->parent->sc_width != 4)
return EINVAL;
sc->disk = disk_alloc();
if (sc->disk == NULL)
return ENOMEM;
sc->disk->d_name = "cfid";
sc->disk->d_unit = device_get_unit(dev);
sc->disk->d_open = cfi_disk_open;
sc->disk->d_close = cfi_disk_close;
sc->disk->d_strategy = cfi_disk_strategy;
sc->disk->d_ioctl = cfi_disk_ioctl;
sc->disk->d_dump = NULL; /* NB: no dumps */
sc->disk->d_getattr = cfi_disk_getattr;
sc->disk->d_sectorsize = CFI_DISK_SECSIZE;
sc->disk->d_mediasize = sc->parent->sc_size;
sc->disk->d_maxsize = CFI_DISK_MAXIOSIZE;
/* NB: use stripesize to hold the erase/region size */
if (sc->parent->sc_regions) {
/*
* Multiple regions, use the last one. This is a
* total hack as it's (presently) used only by
* geom_redboot to locate the FIS directory which
* lies at the start of the last erase region.
*/
sc->disk->d_stripesize =
sc->parent->sc_region[sc->parent->sc_regions-1].r_blksz;
} else
sc->disk->d_stripesize = sc->disk->d_mediasize;
sc->disk->d_drv1 = sc;
disk_create(sc->disk, DISK_VERSION);
mtx_init(&sc->qlock, "CFID I/O lock", NULL, MTX_DEF);
bioq_init(&sc->bioq);
sc->tq = taskqueue_create("cfid_taskq", M_NOWAIT,
taskqueue_thread_enqueue, &sc->tq);
taskqueue_start_threads(&sc->tq, 1, PI_DISK, "cfid taskq");
TASK_INIT(&sc->iotask, 0, cfi_io_proc, sc);
return 0;
}
static int
cfi_disk_detach(device_t dev)
{
struct cfi_disk_softc *sc = device_get_softc(dev);
if (sc->flags & CFI_DISK_OPEN)
return EBUSY;
taskqueue_free(sc->tq);
/* XXX drain bioq */
disk_destroy(sc->disk);
mtx_destroy(&sc->qlock);
return 0;
}
static int
cfi_disk_open(struct disk *dp)
{
struct cfi_disk_softc *sc = dp->d_drv1;
/* XXX no interlock with /dev/cfi */
sc->flags |= CFI_DISK_OPEN;
return 0;
}
static int
cfi_disk_close(struct disk *dp)
{
struct cfi_disk_softc *sc = dp->d_drv1;
sc->flags &= ~CFI_DISK_OPEN;
return 0;
}
static void
cfi_disk_read(struct cfi_softc *sc, struct bio *bp)
{
long resid;
KASSERT(sc->sc_width == 1 || sc->sc_width == 2 || sc->sc_width == 4,
("sc_width %d", sc->sc_width));
if (sc->sc_writing) {
bp->bio_error = cfi_block_finish(sc);
if (bp->bio_error) {
bp->bio_flags |= BIO_ERROR;
goto done;
}
}
if (bp->bio_offset > sc->sc_size) {
bp->bio_flags |= BIO_ERROR;
bp->bio_error = EIO;
goto done;
}
resid = bp->bio_bcount;
if (sc->sc_width == 1) {
uint8_t *dp = (uint8_t *)bp->bio_data;
while (resid > 0 && bp->bio_offset < sc->sc_size) {
*dp++ = cfi_read_raw(sc, bp->bio_offset);
bp->bio_offset += 1, resid -= 1;
}
} else if (sc->sc_width == 2) {
uint16_t *dp = (uint16_t *)bp->bio_data;
while (resid > 0 && bp->bio_offset < sc->sc_size) {
*dp++ = cfi_read_raw(sc, bp->bio_offset);
bp->bio_offset += 2, resid -= 2;
}
} else {
uint32_t *dp = (uint32_t *)bp->bio_data;
while (resid > 0 && bp->bio_offset < sc->sc_size) {
*dp++ = cfi_read_raw(sc, bp->bio_offset);
bp->bio_offset += 4, resid -= 4;
}
}
bp->bio_resid = resid;
done:
biodone(bp);
}
static void
cfi_disk_write(struct cfi_softc *sc, struct bio *bp)
{
long resid;
u_int top;
KASSERT(sc->sc_width == 1 || sc->sc_width == 2 || sc->sc_width == 4,
("sc_width %d", sc->sc_width));
if (bp->bio_offset > sc->sc_size) {
bp->bio_flags |= BIO_ERROR;
bp->bio_error = EIO;
goto done;
}
resid = bp->bio_bcount;
while (resid > 0) {
/*
* Finish the current block if we're about to write
* to a different block.
*/
if (sc->sc_writing) {
top = sc->sc_wrofs + sc->sc_wrbufsz;
if (bp->bio_offset < sc->sc_wrofs ||
bp->bio_offset >= top)
cfi_block_finish(sc);
}
/* Start writing to a (new) block if applicable. */
if (!sc->sc_writing) {
bp->bio_error = cfi_block_start(sc, bp->bio_offset);
if (bp->bio_error) {
bp->bio_flags |= BIO_ERROR;
goto done;
}
}
top = sc->sc_wrofs + sc->sc_wrbufsz;
bcopy(bp->bio_data,
sc->sc_wrbuf + bp->bio_offset - sc->sc_wrofs,
MIN(top - bp->bio_offset, resid));
resid -= MIN(top - bp->bio_offset, resid);
}
bp->bio_resid = resid;
done:
biodone(bp);
}
static void
cfi_io_proc(void *arg, int pending)
{
struct cfi_disk_softc *sc = arg;
struct cfi_softc *cfi = sc->parent;
struct bio *bp;
for (;;) {
mtx_lock(&sc->qlock);
bp = bioq_takefirst(&sc->bioq);
mtx_unlock(&sc->qlock);
if (bp == NULL)
break;
switch (bp->bio_cmd) {
case BIO_READ:
cfi_disk_read(cfi, bp);
break;
case BIO_WRITE:
cfi_disk_write(cfi, bp);
break;
}
}
}
static int
cfi_disk_getattr(struct bio *bp)
{
struct cfi_disk_softc *dsc;
struct cfi_softc *sc;
device_t dev;
if (bp->bio_disk == NULL || bp->bio_disk->d_drv1 == NULL)
return (ENXIO);
dsc = bp->bio_disk->d_drv1;
sc = dsc->parent;
dev = sc->sc_dev;
if (strcmp(bp->bio_attribute, "CFI::device") == 0) {
if (bp->bio_length != sizeof(dev))
return (EFAULT);
bcopy(&dev, bp->bio_data, sizeof(dev));
} else
return (-1);
return (0);
}
static void
cfi_disk_strategy(struct bio *bp)
{
struct cfi_disk_softc *sc = bp->bio_disk->d_drv1;
if (sc == NULL)
goto invalid;
if (bp->bio_bcount == 0) {
bp->bio_resid = bp->bio_bcount;
biodone(bp);
return;
}
switch (bp->bio_cmd) {
case BIO_READ:
case BIO_WRITE:
mtx_lock(&sc->qlock);
/* no value in sorting requests? */
bioq_insert_tail(&sc->bioq, bp);
mtx_unlock(&sc->qlock);
taskqueue_enqueue(sc->tq, &sc->iotask);
return;
}
/* fall thru... */
invalid:
bp->bio_flags |= BIO_ERROR;
bp->bio_error = EINVAL;
biodone(bp);
}
static int
cfi_disk_ioctl(struct disk *dp, u_long cmd, void *data, int fflag,
struct thread *td)
{
return EINVAL;
}
static device_method_t cfi_disk_methods[] = {
DEVMETHOD(device_probe, cfi_disk_probe),
DEVMETHOD(device_attach, cfi_disk_attach),
DEVMETHOD(device_detach, cfi_disk_detach),
{ 0, 0 }
};
static driver_t cfi_disk_driver = {
"cfid",
cfi_disk_methods,
sizeof(struct cfi_disk_softc),
};
DRIVER_MODULE(cfid, cfi, cfi_disk_driver, cfi_diskclass, 0, NULL);