cam_periph.c

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/*
 * Common functions for CAM "type" (peripheral) drivers.
 *
 * Copyright (c) 1997, 1998 Justin T. Gibbs.
 * Copyright (c) 1997, 1998 Kenneth D. Merry.
 * 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.
 *
 *      $Id: cam_periph.c,v 1.9.2.2 1999/05/09 01:27:21 ken Exp $
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/types.h>
#include <sys/malloc.h>
#include <sys/linker_set.h>
#include <sys/buf.h>
#include <sys/proc.h>
#include <sys/devicestat.h>
#include <vm/vm.h>
#include <vm/vm_extern.h>

#include <cam/cam.h>
#include <cam/cam_conf.h>
#include <cam/cam_ccb.h>
#include <cam/cam_xpt_periph.h>
#include <cam/cam_periph.h>
#include <cam/cam_debug.h>

#include <cam/scsi/scsi_all.h>
#include <cam/scsi/scsi_message.h>
#include <cam/scsi/scsi_da.h>
#include <cam/scsi/scsi_pass.h>

static	u_int		camperiphnextunit(struct periph_driver *p_drv,
					  u_int newunit, int wired);
static	u_int		camperiphunit(struct periph_driver *p_drv,
				      path_id_t path_id_t,
				      target_id_t target, lun_id_t lun); 
static	void		camperiphdone(struct cam_periph *periph, 
					union ccb *done_ccb);
static  void		camperiphfree(struct cam_periph *periph);

cam_status
cam_periph_alloc(periph_ctor_t *periph_ctor,
		 periph_oninv_t *periph_oninvalidate,
		 periph_dtor_t *periph_dtor, periph_start_t *periph_start,
		 char *name, cam_periph_type type, struct cam_path *path,
		 ac_callback_t *ac_callback, ac_code code, void *arg)
{
	struct		periph_driver **p_drv;
	struct		cam_periph *periph;
	struct		cam_periph *cur_periph;
	path_id_t	path_id;
	target_id_t	target_id;
	lun_id_t	lun_id;
	cam_status	status;
	u_int		init_level;
	int s;

	init_level = 0;
	/*
	 * Handle Hot-Plug scenarios.  If there is already a peripheral
	 * of our type assigned to this path, we are likely waiting for
	 * final close on an old, invalidated, peripheral.  If this is
	 * the case, queue up a deferred call to the peripheral's async
	 * handler.  If it looks like a mistaken re-alloation, complain.
	 */
	if ((periph = cam_periph_find(path, name)) != NULL) {

		if ((periph->flags & CAM_PERIPH_INVALID) != 0
		 && (periph->flags & CAM_PERIPH_NEW_DEV_FOUND) == 0) {
			periph->flags |= CAM_PERIPH_NEW_DEV_FOUND;
			periph->deferred_callback = ac_callback;
			periph->deferred_ac = code;
			return (CAM_REQ_INPROG);
		} else {
			printf("cam_periph_alloc: attempt to re-allocate "
			       "valid device %s%d rejected\n",
			       periph->periph_name, periph->unit_number);
		}
		return (CAM_REQ_INVALID);
	}
	
	periph = (struct cam_periph *)malloc(sizeof(*periph), M_DEVBUF,
					     M_NOWAIT);

	if (periph == NULL)
		return (CAM_RESRC_UNAVAIL);
	
	init_level++;

	for (p_drv = (struct periph_driver **)periphdriver_set.ls_items;
	     *p_drv != NULL; p_drv++) {
		if (strcmp((*p_drv)->driver_name, name) == 0)
			break;
	}
	
	path_id = xpt_path_path_id(path);
	target_id = xpt_path_target_id(path);
	lun_id = xpt_path_lun_id(path);
	bzero(periph, sizeof(*periph));
	cam_init_pinfo(&periph->pinfo);
	periph->periph_start = periph_start;
	periph->periph_dtor = periph_dtor;
	periph->periph_oninval = periph_oninvalidate;
	periph->type = type;
	periph->periph_name = name;
	periph->unit_number = camperiphunit(*p_drv, path_id, target_id, lun_id);
	periph->immediate_priority = CAM_PRIORITY_NONE;
	periph->refcount = 0;
	SLIST_INIT(&periph->ccb_list);
	status = xpt_create_path(&path, periph, path_id, target_id, lun_id);
	if (status != CAM_REQ_CMP)
		goto failure;

	periph->path = path;
	init_level++;

	status = xpt_add_periph(periph);

	if (status != CAM_REQ_CMP)
		goto failure;

	s = splsoftcam();
	cur_periph = TAILQ_FIRST(&(*p_drv)->units);
	while (cur_periph != NULL
	    && cur_periph->unit_number < periph->unit_number)
		cur_periph = TAILQ_NEXT(cur_periph, unit_links);

	if (cur_periph != NULL)
		TAILQ_INSERT_BEFORE(cur_periph, periph, unit_links);
	else {
		TAILQ_INSERT_TAIL(&(*p_drv)->units, periph, unit_links);
		(*p_drv)->generation++;
	}

	splx(s);

	init_level++;

	status = periph_ctor(periph, arg);

	if (status == CAM_REQ_CMP)
		init_level++;

failure:
	switch (init_level) {
	case 4:
		/* Initialized successfully */
		break;
	case 3:
		s = splsoftcam();
		TAILQ_REMOVE(&(*p_drv)->units, periph, unit_links);
		splx(s);
		xpt_remove_periph(periph);
	case 2:
		xpt_free_path(periph->path);
	case 1:
		free(periph, M_DEVBUF);
	case 0:
		/* No cleanup to perform. */
		break;
	default:
		panic("cam_periph_alloc: Unkown init level");
	}
	return(status);
}

/*
 * Find a peripheral structure with the specified path, target, lun, 
 * and (optionally) type.  If the name is NULL, this function will return
 * the first peripheral driver that matches the specified path.
 */
struct cam_periph *
cam_periph_find(struct cam_path *path, char *name)
{
	struct periph_driver **p_drv;
	struct cam_periph *periph;
	int s;

	for (p_drv = (struct periph_driver **)periphdriver_set.ls_items;
	     *p_drv != NULL; p_drv++) {

		if (name != NULL && (strcmp((*p_drv)->driver_name, name) != 0))
			continue;

		s = splsoftcam();
		for (periph = TAILQ_FIRST(&(*p_drv)->units); periph != NULL;
		     periph = TAILQ_NEXT(periph, unit_links)) {
			if (xpt_path_comp(periph->path, path) == 0) {
				splx(s);
				return(periph);
			}
		}
		splx(s);
		if (name != NULL)
			return(NULL);
	}
	return(NULL);
}

cam_status
cam_periph_acquire(struct cam_periph *periph)
{
	int s;

	if (periph == NULL)
		return(CAM_REQ_CMP_ERR);

	s = splsoftcam();
	periph->refcount++;
	splx(s);

	return(CAM_REQ_CMP);
}

void
cam_periph_release(struct cam_periph *periph)
{
	int s;

	if (periph == NULL)
		return;

	s = splsoftcam();
	if ((--periph->refcount == 0)
	 && (periph->flags & CAM_PERIPH_INVALID)) {
		camperiphfree(periph);
	}
	splx(s);

}

/*
 * Look for the next unit number that is not currently in use for this
 * peripheral type starting at "newunit".  Also exclude unit numbers that
 * are reserved by for future "hardwiring" unless we already know that this
 * is a potential wired device.  Only assume that the device is "wired" the
 * first time through the loop since after that we'll be looking at unit
 * numbers that did not match a wiring entry.
 */
static u_int
camperiphnextunit(struct periph_driver *p_drv, u_int newunit, int wired)
{
	struct	cam_periph *periph;
	struct	cam_periph_config *periph_conf;
	char	*periph_name;
	int	s;

	s = splsoftcam();
	periph_name = p_drv->driver_name;
	for (;;newunit++) {

		for (periph = TAILQ_FIRST(&p_drv->units);
		     periph != NULL && periph->unit_number != newunit;
		     periph = TAILQ_NEXT(periph, unit_links))
			;

		if (periph != NULL && periph->unit_number == newunit) {
			if (wired != 0) {
				xpt_print_path(periph->path);
				printf("Duplicate Wired Device entry!\n");
				xpt_print_path(periph->path);
				printf("Second device will not be wired\n");
				wired = 0;
			}
			continue;
		}

		for (periph_conf = cam_pinit;
		     wired == 0 && periph_conf->periph_name != NULL;
		     periph_conf++) {

			/*
			 * Don't match entries like "da 4" as a wired down
			 * device, but do match entries like "da 4 target 5"
			 * or even "da 4 scbus 1". 
			 */
			if (IS_SPECIFIED(periph_conf->periph_unit)
			 && (!strcmp(periph_name, periph_conf->periph_name))
			 && (IS_SPECIFIED(periph_conf->target)
			  || IS_SPECIFIED(periph_conf->pathid))
			 && (newunit == periph_conf->periph_unit))
				break;
		}

		if (wired != 0 || periph_conf->periph_name == NULL)
			break;
	}
	splx(s);
	return (newunit);
}

static u_int
camperiphunit(struct periph_driver *p_drv, path_id_t pathid,
	      target_id_t target, lun_id_t lun)
{
	struct cam_periph_config *periph_conf;
	u_int unit;
	int hit;

	unit = 0;
	hit = 0;

	for (periph_conf = cam_pinit;
	     periph_conf->periph_name != NULL;
	     periph_conf++, hit = 0) {

		if (!strcmp(p_drv->driver_name, periph_conf->periph_name)
		 && IS_SPECIFIED(periph_conf->periph_unit)) {

			if (IS_SPECIFIED(periph_conf->pathid)) {

				if (pathid != periph_conf->pathid)
					continue;
				hit++;
			}

			if (IS_SPECIFIED(periph_conf->target)) {

				if (target != periph_conf->target)
					continue;
				hit++;
			}

			if (IS_SPECIFIED(periph_conf->lun)) {

				if (lun != periph_conf->lun)
					continue;
				hit++;
			}

			if (hit != 0) {
				unit = periph_conf->periph_unit;
				break;
			}
		}
	}

	/*
	 * Either start from 0 looking for the next unit or from
	 * the unit number given in the periph_conf.  This way,
	 * if we have wildcard matches, we don't return the same
	 * unit number twice.
	 */
	unit = camperiphnextunit(p_drv, unit, /*wired*/hit);

	return (unit);
}

void
cam_periph_invalidate(struct cam_periph *periph)
{
	int s;

	s = splsoftcam();
	/*
	 * We only call this routine the first time a peripheral is
	 * invalidated.  The oninvalidate() routine is always called at
	 * splsoftcam().
	 */
	if (((periph->flags & CAM_PERIPH_INVALID) == 0)
	 && (periph->periph_oninval != NULL))
		periph->periph_oninval(periph);

	periph->flags |= CAM_PERIPH_INVALID;
	periph->flags &= ~CAM_PERIPH_NEW_DEV_FOUND;

	if (periph->refcount == 0)
		camperiphfree(periph);
	else if (periph->refcount < 0)
		printf("cam_invalidate_periph: refcount < 0!!\n");
	splx(s);
}

static void
camperiphfree(struct cam_periph *periph)
{
	int s;
	struct periph_driver **p_drv;

	for (p_drv = (struct periph_driver **)periphdriver_set.ls_items;
	     *p_drv != NULL; p_drv++) {
		if (strcmp((*p_drv)->driver_name, periph->periph_name) == 0)
			break;
	}
	
	if (periph->periph_dtor != NULL)
		periph->periph_dtor(periph);
	
	s = splsoftcam();
	TAILQ_REMOVE(&(*p_drv)->units, periph, unit_links);
	(*p_drv)->generation++;
	splx(s);

	xpt_remove_periph(periph);

	if (periph->flags & CAM_PERIPH_NEW_DEV_FOUND) {
		union ccb ccb;
		void *arg;

		switch (periph->deferred_ac) {
		case AC_FOUND_DEVICE:
			ccb.ccb_h.func_code = XPT_GDEV_TYPE;
			xpt_setup_ccb(&ccb.ccb_h, periph->path, /*priority*/ 1);
			xpt_action(&ccb);
			arg = &ccb;
			break;
		case AC_PATH_REGISTERED:
			ccb.ccb_h.func_code = XPT_PATH_INQ;
			xpt_setup_ccb(&ccb.ccb_h, periph->path, /*priority*/ 1);
			xpt_action(&ccb);
			arg = &ccb;
			break;
		default:
			arg = NULL;
			break;
		}
		periph->deferred_callback(NULL, periph->deferred_ac,
					  periph->path, arg);
	}
	xpt_free_path(periph->path);
	free(periph, M_DEVBUF);
}

/*
 * Wait interruptibly for an exclusive lock.
 */
int
cam_periph_lock(struct cam_periph *periph, int priority)
{
	int error;

	while ((periph->flags & CAM_PERIPH_LOCKED) != 0) {
		periph->flags |= CAM_PERIPH_LOCK_WANTED;
		if ((error = tsleep(periph, priority, "caplck", 0)) != 0)
			return error;
	}

	if (cam_periph_acquire(periph) != CAM_REQ_CMP)
		return(ENXIO);

	periph->flags |= CAM_PERIPH_LOCKED;
	return 0;
}

/*
 * Unlock and wake up any waiters.
 */
void
cam_periph_unlock(struct cam_periph *periph)
{
	periph->flags &= ~CAM_PERIPH_LOCKED;
	if ((periph->flags & CAM_PERIPH_LOCK_WANTED) != 0) {
		periph->flags &= ~CAM_PERIPH_LOCK_WANTED;
		wakeup(periph);
	}

	cam_periph_release(periph);
}

/*
 * Map user virtual pointers into kernel virtual address space, so we can
 * access the memory.  This won't work on physical pointers, for now it's
 * up to the caller to check for that.  (XXX KDM -- should we do that here
 * instead?)  This also only works for up to MAXPHYS memory.  Since we use
 * buffers to map stuff in and out, we're limited to the buffer size.
 */
int
cam_periph_mapmem(union ccb *ccb, struct cam_periph_map_info *mapinfo)
{
	int numbufs, i;
	int flags[CAM_PERIPH_MAXMAPS];
	u_int8_t **data_ptrs[CAM_PERIPH_MAXMAPS];
	u_int32_t lengths[CAM_PERIPH_MAXMAPS];
	u_int32_t dirs[CAM_PERIPH_MAXMAPS];

	switch(ccb->ccb_h.func_code) {
	case XPT_DEV_MATCH:
		if (ccb->cdm.match_buf_len == 0) {
			printf("cam_periph_mapmem: invalid match buffer "
			       "length 0\n");
			return(EINVAL);
		}
		if (ccb->cdm.pattern_buf_len > 0) {
			data_ptrs[0] = (u_int8_t **)&ccb->cdm.patterns;
			lengths[0] = ccb->cdm.pattern_buf_len;
			dirs[0] = CAM_DIR_OUT;
			data_ptrs[1] = (u_int8_t **)&ccb->cdm.matches;
			lengths[1] = ccb->cdm.match_buf_len;
			dirs[1] = CAM_DIR_IN;
			numbufs = 2;
		} else {
			data_ptrs[0] = (u_int8_t **)&ccb->cdm.matches;
			lengths[0] = ccb->cdm.match_buf_len;
			dirs[0] = CAM_DIR_IN;
			numbufs = 1;
		}
		break;
	case XPT_SCSI_IO:
		if ((ccb->ccb_h.flags & CAM_DIR_MASK) == CAM_DIR_NONE)
			return(0);

		data_ptrs[0] = &ccb->csio.data_ptr;
		lengths[0] = ccb->csio.dxfer_len;