d/freebsd-nq
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
6e9b02cf80
freebsd-nq/sys/cam/scsi/scsi_target.c
Suleiman Souhlal 571dcd15e2 Fix the recent panics/LORs/hangs created by my kqueue commit by: 
- Introducing the possibility of using locks different than mutexes
for the knlist locking. In order to do this, we add three arguments to
knlist_init() to specify the functions to use to lock, unlock and
check if the lock is owned. If these arguments are NULL, we assume
mtx_lock, mtx_unlock and mtx_owned, respectively.

- Using the vnode lock for the knlist locking, when doing kqueue operations
on a vnode. This way, we don't have to lock the vnode while holding a
mutex, in filt_vfsread.

Reviewed by:	jmg
Approved by:	re (scottl), scottl (mentor override)
Pointyhat to:	ssouhlal
Will be happy:	everyone
2005-07-01 16:28:32 +00:00

1188 lines
32 KiB
C
Raw Blame History

/*-
* Generic SCSI Target Kernel Mode Driver
*
* Copyright (c) 2002 Nate Lawson.
* Copyright (c) 1998, 1999, 2001, 2002 Justin T. Gibbs.
* 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, this list of conditions, and the following disclaimer,
* without modification, immediately at the beginning of the file.
* 2. The name of the author 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/conf.h>
#include <sys/malloc.h>
#include <sys/poll.h>
#include <sys/vnode.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/devicestat.h>
#include <cam/cam.h>
#include <cam/cam_ccb.h>
#include <cam/cam_periph.h>
#include <cam/cam_xpt_periph.h>
#include <cam/scsi/scsi_targetio.h>
/* Transaction information attached to each CCB sent by the user */
struct targ_cmd_descr {
struct cam_periph_map_info mapinfo;
TAILQ_ENTRY(targ_cmd_descr) tqe;
union ccb *user_ccb;
int priority;
int func_code;
};
/* Offset into the private CCB area for storing our descriptor */
#define targ_descr periph_priv.entries[1].ptr
TAILQ_HEAD(descr_queue, targ_cmd_descr);
typedef enum {
TARG_STATE_RESV = 0x00, /* Invalid state */
TARG_STATE_OPENED = 0x01, /* Device opened, softc initialized */
TARG_STATE_LUN_ENABLED = 0x02 /* Device enabled for a path */
} targ_state;
/* Per-instance device software context */
struct targ_softc {
/* CCBs (CTIOs, ATIOs, INOTs) pending on the controller */
struct ccb_queue pending_ccb_queue;
/* Command descriptors awaiting CTIO resources from the XPT */
struct descr_queue work_queue;
/* Command descriptors that have been aborted back to the user. */
struct descr_queue abort_queue;
/*
* Queue of CCBs that have been copied out to userland, but our
* userland daemon has not yet seen.
*/
struct ccb_queue user_ccb_queue;
struct cam_periph *periph;
struct cam_path *path;
targ_state state;
struct selinfo read_select;
struct devstat device_stats;
struct mtx mtx;
};
static d_open_t targopen;
static d_close_t targclose;
static d_read_t targread;
static d_write_t targwrite;
static d_ioctl_t targioctl;
static d_poll_t targpoll;
static d_kqfilter_t targkqfilter;
static void targreadfiltdetach(struct knote *kn);
static int targreadfilt(struct knote *kn, long hint);
static struct filterops targread_filtops =
{ 1, NULL, targreadfiltdetach, targreadfilt };
static struct cdevsw targ_cdevsw = {
.d_version = D_VERSION,
.d_flags = D_NEEDGIANT,
.d_open = targopen,
.d_close = targclose,
.d_read = targread,
.d_write = targwrite,
.d_ioctl = targioctl,
.d_poll = targpoll,
.d_name = "targ",
.d_kqfilter = targkqfilter
};
static cam_status targendislun(struct cam_path *path, int enable,
int grp6_len, int grp7_len);
static cam_status targenable(struct targ_softc *softc,
struct cam_path *path,
int grp6_len, int grp7_len);
static cam_status targdisable(struct targ_softc *softc);
static periph_ctor_t targctor;
static periph_dtor_t targdtor;
static periph_start_t targstart;
static int targusermerge(struct targ_softc *softc,
struct targ_cmd_descr *descr,
union ccb *ccb);
static int targsendccb(struct targ_softc *softc, union ccb *ccb,
struct targ_cmd_descr *descr);
static void targdone(struct cam_periph *periph,
union ccb *done_ccb);
static int targreturnccb(struct targ_softc *softc,
union ccb *ccb);
static union ccb * targgetccb(struct targ_softc *softc, xpt_opcode type,
int priority);
static void targfreeccb(struct targ_softc *softc, union ccb *ccb);
static struct targ_cmd_descr *
targgetdescr(struct targ_softc *softc);
static periph_init_t targinit;
static void targclone(void *arg, char *name, int namelen,
struct cdev **dev);
static void targasync(void *callback_arg, u_int32_t code,
struct cam_path *path, void *arg);
static void abort_all_pending(struct targ_softc *softc);
static void notify_user(struct targ_softc *softc);
static int targcamstatus(cam_status status);
static size_t targccblen(xpt_opcode func_code);
static struct periph_driver targdriver =
{
targinit, "targ",
TAILQ_HEAD_INITIALIZER(targdriver.units), /* generation */ 0
};
PERIPHDRIVER_DECLARE(targ, targdriver);
static struct mtx targ_mtx;
#define TARG_LOCK(softc) mtx_lock(&(softc)->mtx)
#define TARG_UNLOCK(softc) mtx_unlock(&(softc)->mtx)
static MALLOC_DEFINE(M_TARG, "TARG", "TARG data");
/* Create softc and initialize it. Only one proc can open each targ device. */
static int
targopen(struct cdev *dev, int flags, int fmt, struct thread *td)
{
struct targ_softc *softc;
mtx_lock(&targ_mtx);
if (dev->si_drv1 != 0) {
mtx_unlock(&targ_mtx);
return (EBUSY);
}
/* Mark device busy before any potentially blocking operations */
dev->si_drv1 = (void *)~0;
mtx_unlock(&targ_mtx);
/* Create the targ device, allocate its softc, initialize it */
if ((dev->si_flags & SI_NAMED) == 0) {
make_dev(&targ_cdevsw, minor(dev), UID_ROOT, GID_WHEEL, 0600,
"targ%d", dev2unit(dev));
}
MALLOC(softc, struct targ_softc *, sizeof(*softc), M_TARG,
M_WAITOK | M_ZERO);
dev->si_drv1 = softc;
softc->state = TARG_STATE_OPENED;
softc->periph = NULL;
softc->path = NULL;
mtx_init(&softc->mtx, devtoname(dev), "targ cdev", MTX_DEF);
TAILQ_INIT(&softc->pending_ccb_queue);
TAILQ_INIT(&softc->work_queue);
TAILQ_INIT(&softc->abort_queue);
TAILQ_INIT(&softc->user_ccb_queue);
knlist_init(&softc->read_select.si_note, &softc->mtx, NULL, NULL, NULL);
return (0);
}
/* Disable LUN if enabled and teardown softc */
static int
targclose(struct cdev *dev, int flag, int fmt, struct thread *td)
{
struct targ_softc *softc;
int error;
softc = (struct targ_softc *)dev->si_drv1;
TARG_LOCK(softc);
error = targdisable(softc);
if (error == CAM_REQ_CMP) {
dev->si_drv1 = 0;
mtx_lock(&targ_mtx);
if (softc->periph != NULL) {
cam_periph_invalidate(softc->periph);
softc->periph = NULL;
}
mtx_unlock(&targ_mtx);
TARG_UNLOCK(softc);
mtx_destroy(&softc->mtx);
destroy_dev(dev);
FREE(softc, M_TARG);
} else {
TARG_UNLOCK(softc);
}
return (error);
}
/* Enable/disable LUNs, set debugging level */
static int
targioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flag, struct thread *td)
{
struct targ_softc *softc;
cam_status status;
softc = (struct targ_softc *)dev->si_drv1;
switch (cmd) {
case TARGIOCENABLE:
{
struct ioc_enable_lun *new_lun;
struct cam_path *path;
new_lun = (struct ioc_enable_lun *)addr;
status = xpt_create_path(&path, /*periph*/NULL,
new_lun->path_id,
new_lun->target_id,
new_lun->lun_id);
if (status != CAM_REQ_CMP) {
printf("Couldn't create path, status %#x\n", status);
break;
}
TARG_LOCK(softc);
status = targenable(softc, path, new_lun->grp6_len,
new_lun->grp7_len);
TARG_UNLOCK(softc);
xpt_free_path(path);
break;
}
case TARGIOCDISABLE:
TARG_LOCK(softc);
status = targdisable(softc);
TARG_UNLOCK(softc);
break;
case TARGIOCDEBUG:
{
#ifdef CAMDEBUG
struct ccb_debug cdbg;
bzero(&cdbg, sizeof cdbg);
if (*((int *)addr) != 0)
cdbg.flags = CAM_DEBUG_PERIPH;
else
cdbg.flags = CAM_DEBUG_NONE;
xpt_setup_ccb(&cdbg.ccb_h, softc->path, /*priority*/0);
cdbg.ccb_h.func_code = XPT_DEBUG;
cdbg.ccb_h.cbfcnp = targdone;
/* If no periph available, disallow debugging changes */
TARG_LOCK(softc);
if ((softc->state & TARG_STATE_LUN_ENABLED) == 0) {
status = CAM_DEV_NOT_THERE;
TARG_UNLOCK(softc);
break;
}
xpt_action((union ccb *)&cdbg);
TARG_UNLOCK(softc);
status = cdbg.ccb_h.status & CAM_STATUS_MASK;
#else
status = CAM_FUNC_NOTAVAIL;
#endif
break;
}
default:
status = CAM_PROVIDE_FAIL;
break;
}
return (targcamstatus(status));
}
/* Writes are always ready, reads wait for user_ccb_queue or abort_queue */
static int
targpoll(struct cdev *dev, int poll_events, struct thread *td)
{
struct targ_softc *softc;
int revents;
softc = (struct targ_softc *)dev->si_drv1;
/* Poll for write() is always ok. */
revents = poll_events & (POLLOUT | POLLWRNORM);
if ((poll_events & (POLLIN | POLLRDNORM)) != 0) {
/* Poll for read() depends on user and abort queues. */
TARG_LOCK(softc);
if (!TAILQ_EMPTY(&softc->user_ccb_queue) ||
!TAILQ_EMPTY(&softc->abort_queue)) {
revents |= poll_events & (POLLIN | POLLRDNORM);
}
/* Only sleep if the user didn't poll for write. */
if (revents == 0)
selrecord(td, &softc->read_select);
TARG_UNLOCK(softc);
}
return (revents);
}
static int
targkqfilter(struct cdev *dev, struct knote *kn)
{
struct targ_softc *softc;
softc = (struct targ_softc *)dev->si_drv1;
kn->kn_hook = (caddr_t)softc;
kn->kn_fop = &targread_filtops;
knlist_add(&softc->read_select.si_note, kn, 0);
return (0);
}
static void
targreadfiltdetach(struct knote *kn)
{
struct targ_softc *softc;
softc = (struct targ_softc *)kn->kn_hook;
knlist_remove(&softc->read_select.si_note, kn, 0);
}
/* Notify the user's kqueue when the user queue or abort queue gets a CCB */
static int
targreadfilt(struct knote *kn, long hint)
{
struct targ_softc *softc;
int retval;
softc = (struct targ_softc *)kn->kn_hook;
retval = !TAILQ_EMPTY(&softc->user_ccb_queue) ||
!TAILQ_EMPTY(&softc->abort_queue);
return (retval);
}
/* Send the HBA the enable/disable message */
static cam_status
targendislun(struct cam_path *path, int enable, int grp6_len, int grp7_len)
{
struct ccb_en_lun en_ccb;
cam_status status;
/* Tell the lun to begin answering selects */
xpt_setup_ccb(&en_ccb.ccb_h, path, /*priority*/1);
en_ccb.ccb_h.func_code = XPT_EN_LUN;
/* Don't need support for any vendor specific commands */
en_ccb.grp6_len = grp6_len;
en_ccb.grp7_len = grp7_len;
en_ccb.enable = enable ? 1 : 0;
xpt_action((union ccb *)&en_ccb);
status = en_ccb.ccb_h.status & CAM_STATUS_MASK;
if (status != CAM_REQ_CMP) {
xpt_print_path(path);
printf("%sable lun CCB rejected, status %#x\n",
enable ? "en" : "dis", status);
}
return (status);
}
/* Enable target mode on a LUN, given its path */
static cam_status
targenable(struct targ_softc *softc, struct cam_path *path, int grp6_len,
int grp7_len)
{
struct cam_periph *periph;
struct ccb_pathinq cpi;
cam_status status;
if ((softc->state & TARG_STATE_LUN_ENABLED) != 0)
return (CAM_LUN_ALRDY_ENA);
/* Make sure SIM supports target mode */
xpt_setup_ccb(&cpi.ccb_h, path, /*priority*/1);
cpi.ccb_h.func_code = XPT_PATH_INQ;
xpt_action((union ccb *)&cpi);
status = cpi.ccb_h.status & CAM_STATUS_MASK;
if (status != CAM_REQ_CMP) {
printf("pathinq failed, status %#x\n", status);
goto enable_fail;
}
if ((cpi.target_sprt & PIT_PROCESSOR) == 0) {
printf("controller does not support target mode\n");
status = CAM_FUNC_NOTAVAIL;
goto enable_fail;
}
/* Destroy any periph on our path if it is disabled */
mtx_lock(&targ_mtx);
periph = cam_periph_find(path, "targ");
if (periph != NULL) {
struct targ_softc *del_softc;
del_softc = (struct targ_softc *)periph->softc;
if ((del_softc->state & TARG_STATE_LUN_ENABLED) == 0) {
cam_periph_invalidate(del_softc->periph);
del_softc->periph = NULL;
} else {
printf("Requested path still in use by targ%d\n",
periph->unit_number);
mtx_unlock(&targ_mtx);
status = CAM_LUN_ALRDY_ENA;
goto enable_fail;
}
}
/* Create a periph instance attached to this path */
status = cam_periph_alloc(targctor, NULL, targdtor, targstart,
"targ", CAM_PERIPH_BIO, path, targasync, 0, softc);
mtx_unlock(&targ_mtx);
if (status != CAM_REQ_CMP) {
printf("cam_periph_alloc failed, status %#x\n", status);
goto enable_fail;
}
/* Ensure that the periph now exists. */
if (cam_periph_find(path, "targ") == NULL) {
panic("targenable: succeeded but no periph?");
/* NOTREACHED */
}
/* Send the enable lun message */
status = targendislun(path, /*enable*/1, grp6_len, grp7_len);
if (status != CAM_REQ_CMP) {
printf("enable lun failed, status %#x\n", status);
goto enable_fail;
}
softc->state |= TARG_STATE_LUN_ENABLED;
enable_fail:
return (status);
}
/* Disable this softc's target instance if enabled */
static cam_status
targdisable(struct targ_softc *softc)
{
cam_status status;
if ((softc->state & TARG_STATE_LUN_ENABLED) == 0)
return (CAM_REQ_CMP);
CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targdisable\n"));
/* Abort any ccbs pending on the controller */
abort_all_pending(softc);
/* Disable this lun */
status = targendislun(softc->path, /*enable*/0,
/*grp6_len*/0, /*grp7_len*/0);
if (status == CAM_REQ_CMP)
softc->state &= ~TARG_STATE_LUN_ENABLED;
else
printf("Disable lun failed, status %#x\n", status);
return (status);
}
/* Initialize a periph (called from cam_periph_alloc) */
static cam_status
targctor(struct cam_periph *periph, void *arg)
{
struct targ_softc *softc;
/* Store pointer to softc for periph-driven routines */
softc = (struct targ_softc *)arg;
periph->softc = softc;
softc->periph = periph;
softc->path = periph->path;
return (CAM_REQ_CMP);
}
static void
targdtor(struct cam_periph *periph)
{
struct targ_softc *softc;
struct ccb_hdr *ccb_h;
struct targ_cmd_descr *descr;
softc = (struct targ_softc *)periph->softc;
/*
* targdisable() aborts CCBs back to the user and leaves them
* on user_ccb_queue and abort_queue in case the user is still
* interested in them. We free them now.
*/
while ((ccb_h = TAILQ_FIRST(&softc->user_ccb_queue)) != NULL) {
TAILQ_REMOVE(&softc->user_ccb_queue, ccb_h, periph_links.tqe);
targfreeccb(softc, (union ccb *)ccb_h);
}
while ((descr = TAILQ_FIRST(&softc->abort_queue)) != NULL) {
TAILQ_REMOVE(&softc->abort_queue, descr, tqe);
FREE(descr, M_TARG);
}
softc->periph = NULL;
softc->path = NULL;
periph->softc = NULL;
}
/* Receive CCBs from user mode proc and send them to the HBA */
static int
targwrite(struct cdev *dev, struct uio *uio, int ioflag)
{
union ccb *user_ccb;
struct targ_softc *softc;
struct targ_cmd_descr *descr;
int write_len, error;
int func_code, priority;
softc = (struct targ_softc *)dev->si_drv1;
write_len = error = 0;
CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
("write - uio_resid %d\n", uio->uio_resid));
while (uio->uio_resid >= sizeof(user_ccb) && error == 0) {
union ccb *ccb;
error = uiomove((caddr_t)&user_ccb, sizeof(user_ccb), uio);
if (error != 0) {
CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
("write - uiomove failed (%d)\n", error));
break;
}
priority = fuword32(&user_ccb->ccb_h.pinfo.priority);
if (priority == -1) {
error = EINVAL;
break;
}
func_code = fuword32(&user_ccb->ccb_h.func_code);
switch (func_code) {
case XPT_ACCEPT_TARGET_IO:
case XPT_IMMED_NOTIFY:
ccb = targgetccb(softc, func_code, priority);
descr = (struct targ_cmd_descr *)ccb->ccb_h.targ_descr;
descr->user_ccb = user_ccb;
descr->func_code = func_code;
CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
("Sent ATIO/INOT (%p)\n", user_ccb));
xpt_action(ccb);
TARG_LOCK(softc);
TAILQ_INSERT_TAIL(&softc->pending_ccb_queue,
&ccb->ccb_h,
periph_links.tqe);
TARG_UNLOCK(softc);
break;
default:
if ((func_code & XPT_FC_QUEUED) != 0) {
CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
("Sending queued ccb %#x (%p)\n",
func_code, user_ccb));
descr = targgetdescr(softc);
descr->user_ccb = user_ccb;
descr->priority = priority;
descr->func_code = func_code;
TARG_LOCK(softc);
TAILQ_INSERT_TAIL(&softc->work_queue,
descr, tqe);
TARG_UNLOCK(softc);
xpt_schedule(softc->periph, priority);
} else {
CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
("Sending inline ccb %#x (%p)\n",
func_code, user_ccb));
ccb = targgetccb(softc, func_code, priority);
descr = (struct targ_cmd_descr *)
ccb->ccb_h.targ_descr;
descr->user_ccb = user_ccb;
descr->priority = priority;
descr->func_code = func_code;
if (targusermerge(softc, descr, ccb) != EFAULT)
targsendccb(softc, ccb, descr);
targreturnccb(softc, ccb);
}
break;
}
write_len += sizeof(user_ccb);
}
/*
* If we've successfully taken in some amount of
* data, return success for that data first. If
* an error is persistent, it will be reported
* on the next write.
*/
if (error != 0 && write_len == 0)
return (error);
if (write_len == 0 && uio->uio_resid != 0)
return (ENOSPC);
return (0);
}
/* Process requests (descrs) via the periph-supplied CCBs */
static void
targstart(struct cam_periph *periph, union ccb *start_ccb)
{
struct targ_softc *softc;
struct targ_cmd_descr *descr, *next_descr;
int error;
softc = (struct targ_softc *)periph->softc;
CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targstart %p\n", start_ccb));
TARG_LOCK(softc);
descr = TAILQ_FIRST(&softc->work_queue);
if (descr == NULL) {
TARG_UNLOCK(softc);
xpt_release_ccb(start_ccb);
} else {
TAILQ_REMOVE(&softc->work_queue, descr, tqe);
next_descr = TAILQ_FIRST(&softc->work_queue);
TARG_UNLOCK(softc);
/* Initiate a transaction using the descr and supplied CCB */
error = targusermerge(softc, descr, start_ccb);
if (error == 0)
error = targsendccb(softc, start_ccb, descr);
if (error != 0) {
xpt_print_path(periph->path);
printf("targsendccb failed, err %d\n", error);
xpt_release_ccb(start_ccb);
suword(&descr->user_ccb->ccb_h.status,
CAM_REQ_CMP_ERR);
TARG_LOCK(softc);
TAILQ_INSERT_TAIL(&softc->abort_queue, descr, tqe);
TARG_UNLOCK(softc);
notify_user(softc);
}
/* If we have more work to do, stay scheduled */
if (next_descr != NULL)
xpt_schedule(periph, next_descr->priority);
}
}
static int
targusermerge(struct targ_softc *softc, struct targ_cmd_descr *descr,
union ccb *ccb)
{
struct ccb_hdr *u_ccbh, *k_ccbh;
size_t ccb_len;
int error;
u_ccbh = &descr->user_ccb->ccb_h;
k_ccbh = &ccb->ccb_h;
/*
* There are some fields in the CCB header that need to be
* preserved, the rest we get from the user ccb. (See xpt_merge_ccb)
*/
xpt_setup_ccb(k_ccbh, softc->path, descr->priority);
k_ccbh->retry_count = fuword32(&u_ccbh->retry_count);
k_ccbh->func_code = descr->func_code;
k_ccbh->flags = fuword32(&u_ccbh->flags);
k_ccbh->timeout = fuword32(&u_ccbh->timeout);
ccb_len = targccblen(k_ccbh->func_code) - sizeof(struct ccb_hdr);
error = copyin(u_ccbh + 1, k_ccbh + 1, ccb_len);
if (error != 0) {
k_ccbh->status = CAM_REQ_CMP_ERR;
return (error);
}
/* Translate usermode abort_ccb pointer to its kernel counterpart */
if (k_ccbh->func_code == XPT_ABORT) {
struct ccb_abort *cab;
struct ccb_hdr *ccb_h;
cab = (struct ccb_abort *)ccb;
TARG_LOCK(softc);
TAILQ_FOREACH(ccb_h, &softc->pending_ccb_queue,
periph_links.tqe) {
struct targ_cmd_descr *ab_descr;
ab_descr = (struct targ_cmd_descr *)ccb_h->targ_descr;
if (ab_descr->user_ccb == cab->abort_ccb) {
CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
("Changing abort for %p to %p\n",
cab->abort_ccb, ccb_h));
cab->abort_ccb = (union ccb *)ccb_h;
break;
}
}
TARG_UNLOCK(softc);
/* CCB not found, set appropriate status */
if (ccb_h == NULL) {
k_ccbh->status = CAM_PATH_INVALID;
error = ESRCH;
}
}
return (error);
}
/* Build and send a kernel CCB formed from descr->user_ccb */
static int
targsendccb(struct targ_softc *softc, union ccb *ccb,
struct targ_cmd_descr *descr)
{
struct cam_periph_map_info *mapinfo;
struct ccb_hdr *ccb_h;
int error;
ccb_h = &ccb->ccb_h;
mapinfo = &descr->mapinfo;
mapinfo->num_bufs_used = 0;
/*
* There's no way for the user to have a completion
* function, so we put our own completion function in here.
* We also stash in a reference to our descriptor so targreturnccb()
* can find our mapping info.
*/
ccb_h->cbfcnp = targdone;
ccb_h->targ_descr = descr;
/*
* We only attempt to map the user memory into kernel space
* if they haven't passed in a physical memory pointer,
* and if there is actually an I/O operation to perform.
* Right now cam_periph_mapmem() only supports SCSI and device
* match CCBs. For the SCSI CCBs, we only pass the CCB in if
* there's actually data to map. cam_periph_mapmem() will do the
* right thing, even if there isn't data to map, but since CCBs
* without data are a reasonably common occurance (e.g. test unit
* ready), it will save a few cycles if we check for it here.
*/
if (((ccb_h->flags & CAM_DATA_PHYS) == 0)
&& (((ccb_h->func_code == XPT_CONT_TARGET_IO)
&& ((ccb_h->flags & CAM_DIR_MASK) != CAM_DIR_NONE))
|| (ccb_h->func_code == XPT_DEV_MATCH))) {
error = cam_periph_mapmem(ccb, mapinfo);
/*
* cam_periph_mapmem returned an error, we can't continue.
* Return the error to the user.
*/
if (error) {
ccb_h->status = CAM_REQ_CMP_ERR;
mapinfo->num_bufs_used = 0;
return (error);
}
}
/*
* Once queued on the pending CCB list, this CCB will be protected
* by our error recovery handler.
*/
CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("sendccb %p\n", ccb));
if (XPT_FC_IS_QUEUED(ccb)) {
TARG_LOCK(softc);
TAILQ_INSERT_TAIL(&softc->pending_ccb_queue, ccb_h,
periph_links.tqe);
TARG_UNLOCK(softc);
}
xpt_action(ccb);
return (0);
}
/* Completion routine for CCBs (called at splsoftcam) */
static void
targdone(struct cam_periph *periph, union ccb *done_ccb)
{
struct targ_softc *softc;
cam_status status;
CAM_DEBUG(periph->path, CAM_DEBUG_PERIPH, ("targdone %p\n", done_ccb));
softc = (struct targ_softc *)periph->softc;
TARG_LOCK(softc);
TAILQ_REMOVE(&softc->pending_ccb_queue, &done_ccb->ccb_h,
periph_links.tqe);
status = done_ccb->ccb_h.status & CAM_STATUS_MASK;
/* If we're no longer enabled, throw away CCB */
if ((softc->state & TARG_STATE_LUN_ENABLED) == 0) {
targfreeccb(softc, done_ccb);
TARG_UNLOCK(softc);
return;
}
/* abort_all_pending() waits for pending queue to be empty */
if (TAILQ_EMPTY(&softc->pending_ccb_queue))
wakeup(&softc->pending_ccb_queue);
switch (done_ccb->ccb_h.func_code) {
/* All FC_*_QUEUED CCBs go back to userland */
case XPT_IMMED_NOTIFY:
case XPT_ACCEPT_TARGET_IO:
case XPT_CONT_TARGET_IO:
TAILQ_INSERT_TAIL(&softc->user_ccb_queue, &done_ccb->ccb_h,
periph_links.tqe);
TARG_UNLOCK(softc);
notify_user(softc);
break;
default:
panic("targdone: impossible xpt opcode %#x",
done_ccb->ccb_h.func_code);
/* NOTREACHED */
}
}
/* Return CCBs to the user from the user queue and abort queue */
static int
targread(struct cdev *dev, struct uio *uio, int ioflag)
{
struct descr_queue *abort_queue;
struct targ_cmd_descr *user_descr;
struct targ_softc *softc;
struct ccb_queue *user_queue;
struct ccb_hdr *ccb_h;
union ccb *user_ccb;
int read_len, error;
error = 0;
read_len = 0;
softc = (struct targ_softc *)dev->si_drv1;
user_queue = &softc->user_ccb_queue;
abort_queue = &softc->abort_queue;
CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targread\n"));
/* If no data is available, wait or return immediately */
TARG_LOCK(softc);
ccb_h = TAILQ_FIRST(user_queue);
user_descr = TAILQ_FIRST(abort_queue);
while (ccb_h == NULL && user_descr == NULL) {
if ((ioflag & IO_NDELAY) == 0) {
error = msleep(user_queue, &softc->mtx,
PRIBIO | PCATCH, "targrd", 0);
ccb_h = TAILQ_FIRST(user_queue);
user_descr = TAILQ_FIRST(abort_queue);
if (error != 0) {
if (error == ERESTART) {
continue;
} else {
TARG_UNLOCK(softc);
goto read_fail;
}
}
} else {
TARG_UNLOCK(softc);
return (EAGAIN);
}
}
/* Data is available so fill the user's buffer */
while (ccb_h != NULL) {
struct targ_cmd_descr *descr;
if (uio->uio_resid < sizeof(user_ccb))
break;
TAILQ_REMOVE(user_queue, ccb_h, periph_links.tqe);
TARG_UNLOCK(softc);
descr = (struct targ_cmd_descr *)ccb_h->targ_descr;
user_ccb = descr->user_ccb;
CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
("targread ccb %p (%p)\n", ccb_h, user_ccb));
error = targreturnccb(softc, (union ccb *)ccb_h);
if (error != 0)
goto read_fail;
error = uiomove((caddr_t)&user_ccb, sizeof(user_ccb), uio);
if (error != 0)
goto read_fail;
read_len += sizeof(user_ccb);
TARG_LOCK(softc);
ccb_h = TAILQ_FIRST(user_queue);
}
/* Flush out any aborted descriptors */
while (user_descr != NULL) {
if (uio->uio_resid < sizeof(user_ccb))
break;
TAILQ_REMOVE(abort_queue, user_descr, tqe);
TARG_UNLOCK(softc);
user_ccb = user_descr->user_ccb;
CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
("targread aborted descr %p (%p)\n",
user_descr, user_ccb));
suword(&user_ccb->ccb_h.status, CAM_REQ_ABORTED);
error = uiomove((caddr_t)&user_ccb, sizeof(user_ccb), uio);
if (error != 0)
goto read_fail;
read_len += sizeof(user_ccb);
TARG_LOCK(softc);
user_descr = TAILQ_FIRST(abort_queue);
}
TARG_UNLOCK(softc);
/*
* If we've successfully read some amount of data, don't report an
* error. If the error is persistent, it will be reported on the
* next read().
*/
if (read_len == 0 && uio->uio_resid != 0)
error = ENOSPC;
read_fail:
return (error);
}
/* Copy completed ccb back to the user */
static int
targreturnccb(struct targ_softc *softc, union ccb *ccb)
{
struct targ_cmd_descr *descr;
struct ccb_hdr *u_ccbh;
size_t ccb_len;
int error;
CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("targreturnccb %p\n", ccb));
descr = (struct targ_cmd_descr *)ccb->ccb_h.targ_descr;
u_ccbh = &descr->user_ccb->ccb_h;
/* Copy out the central portion of the ccb_hdr */
copyout(&ccb->ccb_h.retry_count, &u_ccbh->retry_count,
offsetof(struct ccb_hdr, periph_priv) -
offsetof(struct ccb_hdr, retry_count));
/* Copy out the rest of the ccb (after the ccb_hdr) */
ccb_len = targccblen(ccb->ccb_h.func_code) - sizeof(struct ccb_hdr);
if (descr->mapinfo.num_bufs_used != 0)
cam_periph_unmapmem(ccb, &descr->mapinfo);
error = copyout(&ccb->ccb_h + 1, u_ccbh + 1, ccb_len);
if (error != 0) {
xpt_print_path(softc->path);
printf("targreturnccb - CCB copyout failed (%d)\n",
error);
}
/* Free CCB or send back to devq. */
targfreeccb(softc, ccb);
return (error);
}
static union ccb *
targgetccb(struct targ_softc *softc, xpt_opcode type, int priority)
{
union ccb *ccb;
int ccb_len;
ccb_len = targccblen(type);
MALLOC(ccb, union ccb *, ccb_len, M_TARG, M_WAITOK);
CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("getccb %p\n", ccb));
xpt_setup_ccb(&ccb->ccb_h, softc->path, priority);
ccb->ccb_h.func_code = type;
ccb->ccb_h.cbfcnp = targdone;
ccb->ccb_h.targ_descr = targgetdescr(softc);
return (ccb);
}
static void
targfreeccb(struct targ_softc *softc, union ccb *ccb)
{
CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH, ("targfreeccb descr %p and\n",
ccb->ccb_h.targ_descr));
FREE(ccb->ccb_h.targ_descr, M_TARG);
switch (ccb->ccb_h.func_code) {
case XPT_ACCEPT_TARGET_IO:
case XPT_IMMED_NOTIFY:
CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH, ("freeing ccb %p\n", ccb));
FREE(ccb, M_TARG);
break;
default:
/* Send back CCB if we got it from the periph */
if (XPT_FC_IS_QUEUED(ccb)) {
CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH,
("returning queued ccb %p\n", ccb));
xpt_release_ccb(ccb);
} else {
CAM_DEBUG_PRINT(CAM_DEBUG_PERIPH,
("freeing ccb %p\n", ccb));
FREE(ccb, M_TARG);
}
break;
}
}
static struct targ_cmd_descr *
targgetdescr(struct targ_softc *softc)
{
struct targ_cmd_descr *descr;
MALLOC(descr, struct targ_cmd_descr *, sizeof(*descr), M_TARG,
M_WAITOK);
descr->mapinfo.num_bufs_used = 0;
return (descr);
}
static void
targinit(void)
{
mtx_init(&targ_mtx, "targ global", NULL, MTX_DEF);
EVENTHANDLER_REGISTER(dev_clone, targclone, 0, 1000);
}
static void
targclone(void *arg, char *name, int namelen, struct cdev **dev)
{
int u;
if (*dev != NULL)
return;
if (dev_stdclone(name, NULL, "targ", &u) != 1)
return;
*dev = make_dev(&targ_cdevsw, unit2minor(u), UID_ROOT, GID_WHEEL,
0600, "targ%d", u);
dev_ref(*dev);
(*dev)->si_flags |= SI_CHEAPCLONE;
}
static void
targasync(void *callback_arg, u_int32_t code, struct cam_path *path, void *arg)
{
/* All events are handled in usermode by INOTs */
panic("targasync() called, should be an INOT instead");
}
/* Cancel all pending requests and CCBs awaiting work. */
static void
abort_all_pending(struct targ_softc *softc)
{
struct targ_cmd_descr *descr;
struct ccb_abort cab;
struct ccb_hdr *ccb_h;
CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH, ("abort_all_pending\n"));
/* First abort the descriptors awaiting resources */
while ((descr = TAILQ_FIRST(&softc->work_queue)) != NULL) {
CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
("Aborting descr from workq %p\n", descr));
TAILQ_REMOVE(&softc->work_queue, descr, tqe);
TAILQ_INSERT_TAIL(&softc->abort_queue, descr, tqe);
}
/*
* Then abort all pending CCBs.
* targdone() will return the aborted CCB via user_ccb_queue
*/
xpt_setup_ccb(&cab.ccb_h, softc->path, /*priority*/0);
cab.ccb_h.func_code = XPT_ABORT;
cab.ccb_h.status = CAM_REQ_CMP_ERR;
TAILQ_FOREACH(ccb_h, &softc->pending_ccb_queue, periph_links.tqe) {
CAM_DEBUG(softc->path, CAM_DEBUG_PERIPH,
("Aborting pending CCB %p\n", ccb_h));
cab.abort_ccb = (union ccb *)ccb_h;
xpt_action((union ccb *)&cab);
if (cab.ccb_h.status != CAM_REQ_CMP) {
xpt_print_path(cab.ccb_h.path);
printf("Unable to abort CCB, status %#x\n",
cab.ccb_h.status);
}
}
/* If we aborted at least one pending CCB ok, wait for it. */
if (cab.ccb_h.status == CAM_REQ_CMP) {
msleep(&softc->pending_ccb_queue, &softc->mtx,
PRIBIO | PCATCH, "tgabrt", 0);
}
/* If we aborted anything from the work queue, wakeup user. */
if (!TAILQ_EMPTY(&softc->user_ccb_queue)
|| !TAILQ_EMPTY(&softc->abort_queue))
notify_user(softc);
}
/* Notify the user that data is ready */
static void
notify_user(struct targ_softc *softc)
{
/*
* Notify users sleeping via poll(), kqueue(), and
* blocking read().
*/
selwakeuppri(&softc->read_select, PRIBIO);
KNOTE_LOCKED(&softc->read_select.si_note, 0);
wakeup(&softc->user_ccb_queue);
}
/* Convert CAM status to errno values */
static int
targcamstatus(cam_status status)
{
switch (status & CAM_STATUS_MASK) {
case CAM_REQ_CMP: /* CCB request completed without error */
return (0);
case CAM_REQ_INPROG: /* CCB request is in progress */
return (EINPROGRESS);
case CAM_REQ_CMP_ERR: /* CCB request completed with an error */
return (EIO);
case CAM_PROVIDE_FAIL: /* Unable to provide requested capability */
return (ENOTTY);
case CAM_FUNC_NOTAVAIL: /* The requested function is not available */
return (ENOTSUP);
case CAM_LUN_ALRDY_ENA: /* LUN is already enabled for target mode */
return (EADDRINUSE);
case CAM_PATH_INVALID: /* Supplied Path ID is invalid */
case CAM_DEV_NOT_THERE: /* SCSI Device Not Installed/there */
return (ENOENT);
case CAM_REQ_ABORTED: /* CCB request aborted by the host */
return (ECANCELED);
case CAM_CMD_TIMEOUT: /* Command timeout */
return (ETIMEDOUT);
case CAM_REQUEUE_REQ: /* Requeue to preserve transaction ordering */
return (EAGAIN);
case CAM_REQ_INVALID: /* CCB request was invalid */
return (EINVAL);
case CAM_RESRC_UNAVAIL: /* Resource Unavailable */
return (ENOMEM);
case CAM_BUSY: /* CAM subsytem is busy */
case CAM_UA_ABORT: /* Unable to abort CCB request */
return (EBUSY);
default:
return (ENXIO);
}
}
static size_t
targccblen(xpt_opcode func_code)
{
int len;
/* Codes we expect to see as a target */
switch (func_code) {
case XPT_CONT_TARGET_IO:
case XPT_SCSI_IO:
len = sizeof(struct ccb_scsiio);
break;
case XPT_ACCEPT_TARGET_IO:
len = sizeof(struct ccb_accept_tio);
break;
case XPT_IMMED_NOTIFY:
len = sizeof(struct ccb_immed_notify);
break;
case XPT_REL_SIMQ:
len = sizeof(struct ccb_relsim);
break;
case XPT_PATH_INQ:
len = sizeof(struct ccb_pathinq);
break;
case XPT_DEBUG:
len = sizeof(struct ccb_debug);
break;
case XPT_ABORT:
len = sizeof(struct ccb_abort);
break;
case XPT_EN_LUN:
len = sizeof(struct ccb_en_lun);
break;
default:
len = sizeof(union ccb);
break;
}
return (len);
}
Reference in New Issue View Git Blame Copy Permalink