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freebsd-nq/sys/cam/scsi/scsi_target.c

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/*
* Implementation of a simple Target Mode SCSI Proccessor Target driver for CAM.
*
* Copyright (c) 1998, 1999 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.
*
* $Id: scsi_target.c,v 1.6 1998/12/17 00:03:14 gibbs Exp $
*/
#include <stddef.h> /* For offsetof */
#include <sys/param.h>
#include <sys/queue.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/types.h>
#include <sys/buf.h>
#include <sys/conf.h>
#include <sys/devicestat.h>
#include <sys/malloc.h>
#include <sys/poll.h>
#include <sys/select.h> /* For struct selinfo. */
#include <sys/uio.h>
#include <cam/cam.h>
#include <cam/cam_ccb.h>
#include <cam/cam_extend.h>
#include <cam/cam_periph.h>
#include <cam/cam_queue.h>
#include <cam/cam_xpt_periph.h>
#include <cam/cam_debug.h>
#include <cam/scsi/scsi_all.h>
#include <cam/scsi/scsi_pt.h>
#include <cam/scsi/scsi_targetio.h>
#include <cam/scsi/scsi_message.h>
typedef enum {
TARG_STATE_NORMAL,
TARG_STATE_EXCEPTION,
TARG_STATE_TEARDOWN
} targ_state;
typedef enum {
TARG_FLAG_NONE = 0x00,
TARG_FLAG_SEND_EOF = 0x01,
TARG_FLAG_RECEIVE_EOF = 0x02,
TARG_FLAG_LUN_ENABLED = 0x04
} targ_flags;
typedef enum {
TARG_CCB_WORKQ,
TARG_CCB_WAITING
} targ_ccb_types;
#define MAX_ACCEPT 16
#define MAX_IMMEDIATE 16
#define MAX_BUF_SIZE 256 /* Max inquiry/sense/mode page transfer */
#define MAX_INITIATORS 16 /* XXX More for Fibre-Channel */
#define MIN(a, b) ((a > b) ? b : a)
/* Offsets into our private CCB area for storing accept information */
#define ccb_type ppriv_field0
#define ccb_descr ppriv_ptr1
/* We stick a pointer to the originating accept TIO in each continue I/O CCB */
#define ccb_atio ppriv_ptr1
TAILQ_HEAD(ccb_queue, ccb_hdr);
struct targ_softc {
struct ccb_queue pending_queue;
struct ccb_queue work_queue;
struct ccb_queue snd_ccb_queue;
struct ccb_queue rcv_ccb_queue;
struct ccb_queue unknown_atio_queue;
struct buf_queue_head snd_buf_queue;
struct buf_queue_head rcv_buf_queue;
struct devstat device_stats;
struct selinfo snd_select;
struct selinfo rcv_select;
targ_state state;
targ_flags flags;
targ_exception exceptions;
u_int init_level;
u_int inq_data_len;
struct scsi_inquiry_data *inq_data;
struct ccb_accept_tio *accept_tio_list;
struct ccb_hdr_slist immed_notify_slist;
struct initiator_state istate[MAX_INITIATORS];
};
struct targ_cmd_desc {
struct ccb_accept_tio* atio_link;
u_int data_resid; /* How much left to transfer */
u_int data_increment;/* Amount to send before next disconnect */
void* data; /* The data. Can be from backing_store or not */
void* backing_store;/* Backing store allocated for this descriptor*/
struct buf *bp; /* Buffer for this transfer */
u_int max_size; /* Size of backing_store */
u_int32_t timeout;
u_int8_t status; /* Status to return to initiator */
};
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_strategy_t targstrategy;
#define TARG_CDEV_MAJOR 65
static struct cdevsw targ_cdevsw = {
/*d_open*/ targopen,
/*d_close*/ targclose,
/*d_read*/ targread,
/*d_write*/ targwrite,
/*d_ioctl*/ targioctl,
/*d_stop*/ nostop,
/*d_reset*/ noreset,
/*d_devtotty*/ nodevtotty,
/*d_poll*/ targpoll,
/*d_mmap*/ nommap,
/*d_strategy*/ targstrategy,
/*d_name*/ "targ",
/*d_spare*/ NULL,
/*d_maj*/ -1,
/*d_dump*/ nodump,
/*d_psize*/ nopsize,
/*d_flags*/ 0,
/*d_maxio*/ 0,
/*b_maj*/ -1
};
static int targsendccb(struct cam_periph *periph, union ccb *ccb,
union ccb *inccb);
static periph_init_t targinit;
static void targasync(void *callback_arg, u_int32_t code,
struct cam_path *path, void *arg);
static cam_status targenlun(struct cam_periph *periph);
static cam_status targdislun(struct cam_periph *periph);
static periph_ctor_t targctor;
static periph_dtor_t targdtor;
static void targrunqueue(struct cam_periph *periph,
struct targ_softc *softc);
static periph_start_t targstart;
static void targdone(struct cam_periph *periph,
union ccb *done_ccb);
static void targfireexception(struct cam_periph *periph,
struct targ_softc *softc);
static int targerror(union ccb *ccb, u_int32_t cam_flags,
u_int32_t sense_flags);
static struct targ_cmd_desc* allocdescr(void);
static void freedescr(struct targ_cmd_desc *buf);
static void fill_sense(struct scsi_sense_data *sense,
u_int error_code, u_int sense_key,
u_int asc, u_int ascq);
static struct periph_driver targdriver =
{
targinit, "targ",
TAILQ_HEAD_INITIALIZER(targdriver.units), /* generation */ 0
};
DATA_SET(periphdriver_set, targdriver);
static struct extend_array *targperiphs;
static void
targinit(void)
{
cam_status status;
struct cam_path *path;
/*
* Create our extend array for storing the devices we attach to.
*/
targperiphs = cam_extend_new();
if (targperiphs == NULL) {
printf("targ: Failed to alloc extend array!\n");
return;
}
/*
* Install a global async callback. This callback will
* receive async callbacks like "new path registered".
*/
status = xpt_create_path(&path, /*periph*/NULL, CAM_XPT_PATH_ID,
CAM_TARGET_WILDCARD, CAM_LUN_WILDCARD);
if (status == CAM_REQ_CMP) {
struct ccb_setasync csa;
xpt_setup_ccb(&csa.ccb_h, path, /*priority*/5);
csa.ccb_h.func_code = XPT_SASYNC_CB;
csa.event_enable = AC_PATH_REGISTERED;
csa.callback = targasync;
csa.callback_arg = NULL;
xpt_action((union ccb *)&csa);
status = csa.ccb_h.status;
xpt_free_path(path);
}
if (status != CAM_REQ_CMP) {
printf("targ: Failed to attach master async callback "
"due to status 0x%x!\n", status);
} else {
/* If we were successfull, register our devsw */
dev_t dev;
dev = makedev(TARG_CDEV_MAJOR, 0);
cdevsw_add(&dev,&targ_cdevsw, NULL);
}
}
static void
targasync(void *callback_arg, u_int32_t code,
struct cam_path *path, void *arg)
{
struct cam_periph *periph;
periph = (struct cam_periph *)callback_arg;
switch (code) {
case AC_PATH_REGISTERED:
{
struct ccb_pathinq *cpi;
struct cam_path *new_path;
cam_status status;
cpi = (struct ccb_pathinq *)arg;
/* Only attach to controllers that support target mode */
if ((cpi->target_sprt & PIT_PROCESSOR) == 0)
break;
/*
* Allocate a peripheral instance for
* this target instance.
*/
status = xpt_create_path(&new_path, NULL,
xpt_path_path_id(path),
cpi->initiator_id, /*lun*/0);
if (status != CAM_REQ_CMP) {
printf("targasync: Unable to create path "
"due to status 0x%x\n", status);
break;
}
status = cam_periph_alloc(targctor, NULL, targdtor, targstart,
"targ", CAM_PERIPH_BIO,
new_path, targasync,
AC_PATH_REGISTERED,
cpi);
xpt_free_path(new_path);
if (status != CAM_REQ_CMP
&& status != CAM_REQ_INPROG)
printf("targasync: Unable to attach to new device "
"due to status 0x%x\n", status);
break;
}
case AC_PATH_DEREGISTERED:
{
/* XXX Implement */
break;
}
case AC_BUS_RESET:
{
/* Flush transaction queue */
}
default:
break;
}
}
/* Attempt to enable our lun */
static cam_status
targenlun(struct cam_periph *periph)
{
union ccb immed_ccb;
struct targ_softc *softc;
cam_status status;
int i;
softc = (struct targ_softc *)periph->softc;
if ((softc->flags & TARG_FLAG_LUN_ENABLED) != 0)
return (CAM_REQ_CMP);
xpt_setup_ccb(&immed_ccb.ccb_h, periph->path, /*priority*/1);
immed_ccb.ccb_h.func_code = XPT_EN_LUN;
/* Don't need support for any vendor specific commands */
immed_ccb.cel.grp6_len = 0;
immed_ccb.cel.grp7_len = 0;
immed_ccb.cel.enable = 1;
xpt_action(&immed_ccb);
status = immed_ccb.ccb_h.status;
if (status != CAM_REQ_CMP) {
xpt_print_path(periph->path);
printf("targenlun - Enable Lun Rejected for status 0x%x\n",
status);
return (status);
}
softc->flags |= TARG_FLAG_LUN_ENABLED;
/*
* Build up a buffer of accept target I/O
* operations for incoming selections.
*/
for (i = 0; i < MAX_ACCEPT; i++) {
struct ccb_accept_tio *atio;
atio = (struct ccb_accept_tio*)malloc(sizeof(*atio), M_DEVBUF,
M_NOWAIT);
if (atio == NULL) {
status = CAM_RESRC_UNAVAIL;
break;
}
atio->ccb_h.ccb_descr = allocdescr();
if (atio->ccb_h.ccb_descr == NULL) {
free(atio, M_DEVBUF);
status = CAM_RESRC_UNAVAIL;
break;
}
xpt_setup_ccb(&atio->ccb_h, periph->path, /*priority*/1);
atio->ccb_h.func_code = XPT_ACCEPT_TARGET_IO;
atio->ccb_h.cbfcnp = targdone;
xpt_action((union ccb *)atio);
status = atio->ccb_h.status;
if (status != CAM_REQ_INPROG) {
freedescr(atio->ccb_h.ccb_descr);
free(atio, M_DEVBUF);
break;
}
((struct targ_cmd_desc*)atio->ccb_h.ccb_descr)->atio_link =
softc->accept_tio_list;
softc->accept_tio_list = atio;
}
if (i == 0) {
xpt_print_path(periph->path);
printf("targenlun - Could not allocate accept tio CCBs: "
"status = 0x%x\n", status);
targdislun(periph);
return (CAM_REQ_CMP_ERR);
}
/*
* Build up a buffer of immediate notify CCBs
* so the SIM can tell us of asynchronous target mode events.
*/
for (i = 0; i < MAX_ACCEPT; i++) {
struct ccb_immed_notify *inot;
inot = (struct ccb_immed_notify*)malloc(sizeof(*inot), M_DEVBUF,
M_NOWAIT);
if (inot == NULL) {
status = CAM_RESRC_UNAVAIL;
break;
}
xpt_setup_ccb(&inot->ccb_h, periph->path, /*priority*/1);
inot->ccb_h.func_code = XPT_IMMED_NOTIFY;
inot->ccb_h.cbfcnp = targdone;
xpt_action((union ccb *)inot);
status = inot->ccb_h.status;
if (status != CAM_REQ_INPROG) {
free(inot, M_DEVBUF);
break;
}
SLIST_INSERT_HEAD(&softc->immed_notify_slist, &inot->ccb_h,
periph_links.sle);
}
if (i == 0) {
xpt_print_path(periph->path);
printf("targenlun - Could not allocate immediate notify CCBs: "
"status = 0x%x\n", status);
targdislun(periph);
return (CAM_REQ_CMP_ERR);
}
return (CAM_REQ_CMP);
}
static cam_status
targdislun(struct cam_periph *periph)
{
union ccb ccb;
struct targ_softc *softc;
struct ccb_accept_tio* atio;
struct ccb_hdr *ccb_h;
softc = (struct targ_softc *)periph->softc;
if ((softc->flags & TARG_FLAG_LUN_ENABLED) == 0)
return CAM_REQ_CMP;
/* XXX Block for Continue I/O completion */
/* Kill off all ACCECPT and IMMEDIATE CCBs */
while ((atio = softc->accept_tio_list) != NULL) {
softc->accept_tio_list =
((struct targ_cmd_desc*)atio->ccb_h.ccb_descr)->atio_link;
xpt_setup_ccb(&ccb.cab.ccb_h, periph->path, /*priority*/1);
ccb.cab.ccb_h.func_code = XPT_ABORT;
ccb.cab.abort_ccb = (union ccb *)atio;
xpt_action(&ccb);
}
while ((ccb_h = SLIST_FIRST(&softc->immed_notify_slist)) != NULL) {
SLIST_REMOVE_HEAD(&softc->immed_notify_slist, periph_links.sle);
xpt_setup_ccb(&ccb.cab.ccb_h, periph->path, /*priority*/1);
ccb.cab.ccb_h.func_code = XPT_ABORT;
ccb.cab.abort_ccb = (union ccb *)ccb_h;
xpt_action(&ccb);
}
/*
* Dissable this lun.
*/
xpt_setup_ccb(&ccb.cel.ccb_h, periph->path, /*priority*/1);
ccb.cel.ccb_h.func_code = XPT_EN_LUN;
ccb.cel.enable = 0;
xpt_action(&ccb);
if (ccb.cel.ccb_h.status != CAM_REQ_CMP)
printf("targdislun - Disabling lun on controller failed "
"with status 0x%x\n", ccb.cel.ccb_h.status);
else
softc->flags &= ~TARG_FLAG_LUN_ENABLED;
return (ccb.cel.ccb_h.status);
}
static cam_status
targctor(struct cam_periph *periph, void *arg)
{
struct ccb_pathinq *cpi;
struct targ_softc *softc;
int i;
cpi = (struct ccb_pathinq *)arg;
/* Allocate our per-instance private storage */
softc = (struct targ_softc *)malloc(sizeof(*softc), M_DEVBUF, M_NOWAIT);
if (softc == NULL) {
printf("targctor: unable to malloc softc\n");
return (CAM_REQ_CMP_ERR);
}
bzero(softc, sizeof(softc));
TAILQ_INIT(&softc->pending_queue);
TAILQ_INIT(&softc->work_queue);
TAILQ_INIT(&softc->snd_ccb_queue);
TAILQ_INIT(&softc->rcv_ccb_queue);
TAILQ_INIT(&softc->unknown_atio_queue);
bufq_init(&softc->snd_buf_queue);
bufq_init(&softc->rcv_buf_queue);
softc->accept_tio_list = NULL;
SLIST_INIT(&softc->immed_notify_slist);
softc->state = TARG_STATE_NORMAL;
periph->softc = softc;
softc->init_level++;
cam_extend_set(targperiphs, periph->unit_number, periph);
/*
* We start out life with a UA to indicate power-on/reset.
*/
for (i = 0; i < MAX_INITIATORS; i++)
softc->istate[i].pending_ua = UA_POWER_ON;
/*
* Allocate an initial inquiry data buffer. We might allow the
* user to override this later via an ioctl.
*/
softc->inq_data_len = sizeof(*softc->inq_data);
softc->inq_data = malloc(softc->inq_data_len, M_DEVBUF, M_NOWAIT);
if (softc->inq_data == NULL) {
printf("targctor - Unable to malloc inquiry data\n");
targdtor(periph);
}
bzero(softc->inq_data, softc->inq_data_len);
softc->inq_data->device = T_PROCESSOR | (SID_QUAL_LU_CONNECTED << 5);
softc->inq_data->version = 2;
softc->inq_data->response_format = 2; /* SCSI2 Inquiry Format */
softc->inq_data->flags =
cpi->hba_inquiry & (PI_SDTR_ABLE|PI_WIDE_16|PI_WIDE_32);
softc->inq_data->additional_length = softc->inq_data_len - 4;
strncpy(softc->inq_data->vendor, "FreeBSD ", SID_VENDOR_SIZE);
strncpy(softc->inq_data->product, "TM-PT ", SID_PRODUCT_SIZE);
strncpy(softc->inq_data->revision, "0.0 ", SID_REVISION_SIZE);
softc->init_level++;
return (CAM_REQ_CMP);
}
static void
targdtor(struct cam_periph *periph)
{
struct targ_softc *softc;
softc = (struct targ_softc *)periph->softc;
softc->state = TARG_STATE_TEARDOWN;
targdislun(periph);
switch (softc->init_level) {
default:
/* FALLTHROUGH */
case 2:
free(softc->inq_data, M_DEVBUF);
/* FALLTHROUGH */
case 1:
free(softc, M_DEVBUF);
break;
case 0:
panic("targdtor - impossible init level");;
}
}
static int
targopen(dev_t dev, int flags, int fmt, struct proc *p)
{
struct cam_periph *periph;
u_int unit;
cam_status status;
int error;
int s;
unit = minor(dev);
s = splsoftcam();
periph = cam_extend_get(targperiphs, unit);
if (periph == NULL) {
return (ENXIO);
splx(s);
}
if ((error = cam_periph_lock(periph, PRIBIO | PCATCH)) != 0) {
splx(s);
return (error);
}
splx(s);
status = targenlun(periph);
switch (status) {
case CAM_REQ_CMP:
error = 0;
break;
case CAM_RESRC_UNAVAIL:
error = ENOMEM;
break;
case CAM_LUN_ALRDY_ENA:
error = EADDRINUSE;
break;
default:
error = ENXIO;
break;
}
cam_periph_unlock(periph);
return (error);
}
static int
targclose(dev_t dev, int flag, int fmt, struct proc *p)
{
struct cam_periph *periph;
struct targ_softc *softc;
u_int unit;
int s;
int error;
unit = minor(dev);
s = splsoftcam();
periph = cam_extend_get(targperiphs, unit);
if (periph == NULL) {
splx(s);
return (ENXIO);
}
if ((error = cam_periph_lock(periph, PRIBIO)) != 0)
return (error);
softc = (struct targ_softc *)periph->softc;
splx(s);
targdislun(periph);
cam_periph_unlock(periph);
return (0);
}
static int
targioctl(dev_t dev, u_long cmd, caddr_t addr, int flag, struct proc *p)
{
struct cam_periph *periph;
struct targ_softc *softc;
u_int unit;
int error;
unit = minor(dev);
periph = cam_extend_get(targperiphs, unit);
if (periph == NULL)
return (ENXIO);
softc = (struct targ_softc *)periph->softc;
error = 0;
switch (cmd) {
case TARGIOCFETCHEXCEPTION:
*((targ_exception *)addr) = softc->exceptions;
break;
case TARGIOCCLEAREXCEPTION:
{
targ_exception clear_mask;
clear_mask = *((targ_exception *)addr);
if ((clear_mask & TARG_EXCEPT_UNKNOWN_ATIO) != 0) {
struct ccb_hdr *ccbh;
ccbh = TAILQ_FIRST(&softc->unknown_atio_queue);
if (ccbh != NULL) {
TAILQ_REMOVE(&softc->unknown_atio_queue,
ccbh, periph_links.tqe);
ccbh = TAILQ_FIRST(&softc->unknown_atio_queue);
}
if (ccbh != NULL)
clear_mask &= ~TARG_EXCEPT_UNKNOWN_ATIO;
}
softc->exceptions &= ~clear_mask;
if (softc->exceptions == TARG_EXCEPT_NONE
&& softc->state == TARG_STATE_EXCEPTION) {
softc->state = TARG_STATE_NORMAL;
targrunqueue(periph, softc);
}
break;
}
case TARGIOCFETCHATIO:
{
struct ccb_hdr *ccbh;
ccbh = TAILQ_FIRST(&softc->unknown_atio_queue);
if (ccbh != NULL) {
bcopy(ccbh, addr, sizeof(struct ccb_accept_tio));
} else {
error = ENOENT;
}
break;
}
case TARGIOCCOMMAND:
{
union ccb *inccb;
union ccb *ccb;
/*
* XXX JGibbs
* This code is lifted directly from the pass-thru driver.
* Perhaps this should be moved to a library????
*/
inccb = (union ccb *)addr;
ccb = cam_periph_getccb(periph, inccb->ccb_h.pinfo.priority);
error = targsendccb(periph, ccb, inccb);
xpt_release_ccb(ccb);
break;
}
case TARGIOCGETISTATE:
case TARGIOCSETISTATE:
{
struct ioc_initiator_state *ioc_istate;
ioc_istate = (struct ioc_initiator_state *)addr;
if (ioc_istate->initiator_id > MAX_INITIATORS) {
error = EINVAL;
break;
}
CAM_DEBUG(periph->path, CAM_DEBUG_SUBTRACE,
("GET/SETISTATE for %d\n", ioc_istate->initiator_id));
if (cmd == TARGIOCGETISTATE) {
bcopy(&softc->istate[ioc_istate->initiator_id],
&ioc_istate->istate, sizeof(ioc_istate->istate));
} else {
bcopy(&ioc_istate->istate,
&softc->istate[ioc_istate->initiator_id],
sizeof(ioc_istate->istate));
CAM_DEBUG(periph->path, CAM_DEBUG_SUBTRACE,
("pending_ca now %x\n",
softc->istate[ioc_istate->initiator_id].pending_ca));
}
break;
}
default:
error = ENOTTY;
break;
}
return (error);
}
/*
* XXX JGibbs lifted from pass-thru driver.
* Generally, "ccb" should be the CCB supplied by the kernel. "inccb"
* should be the CCB that is copied in from the user.
*/
static int
targsendccb(struct cam_periph *periph, union ccb *ccb, union ccb *inccb)
{
struct targ_softc *softc;
struct cam_periph_map_info mapinfo;
int error, need_unmap;
softc = (struct targ_softc *)periph->softc;
need_unmap = 0;
/*
* There are some fields in the CCB header that need to be
* preserved, the rest we get from the user.
*/
xpt_merge_ccb(ccb, inccb);
/*
* There's no way for the user to have a completion
* function, so we put our own completion function in here.
*/
ccb->ccb_h.cbfcnp = targdone;
/*
* 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->ccb_h.flags & CAM_DATA_PHYS) == 0)
&& (((ccb->ccb_h.func_code == XPT_CONT_TARGET_IO)
&& ((ccb->ccb_h.flags & CAM_DIR_MASK) != CAM_DIR_NONE))
|| (ccb->ccb_h.func_code == XPT_DEV_MATCH))) {
bzero(&mapinfo, sizeof(mapinfo));
error = cam_periph_mapmem(ccb, &mapinfo);
/*
* cam_periph_mapmem returned an error, we can't continue.
* Return the error to the user.
*/
if (error)
return(error);
/*
* We successfully mapped the memory in, so we need to
* unmap it when the transaction is done.
*/
need_unmap = 1;
}
/*
* If the user wants us to perform any error recovery, then honor
* that request. Otherwise, it's up to the user to perform any
* error recovery.
*/
error = cam_periph_runccb(ccb,
(ccb->ccb_h.flags & CAM_PASS_ERR_RECOVER) ?
targerror : NULL,
/* cam_flags */ 0,
/* sense_flags */SF_RETRY_UA,
&softc->device_stats);
if (need_unmap != 0)
cam_periph_unmapmem(ccb, &mapinfo);
ccb->ccb_h.cbfcnp = NULL;
ccb->ccb_h.periph_priv = inccb->ccb_h.periph_priv;
bcopy(ccb, inccb, sizeof(union ccb));
return(error);
}
static int
targpoll(dev_t dev, int poll_events, struct proc *p)
{
struct cam_periph *periph;
struct targ_softc *softc;
u_int unit;
int revents;
int s;
unit = minor(dev);
periph = cam_extend_get(targperiphs, unit);
if (periph == NULL)
return (ENXIO);
softc = (struct targ_softc *)periph->softc;
revents = 0;
s = splcam();
if ((poll_events & (POLLOUT | POLLWRNORM)) != 0) {
if (TAILQ_FIRST(&softc->rcv_ccb_queue) != NULL
&& bufq_first(&softc->rcv_buf_queue) == NULL)
revents |= poll_events & (POLLOUT | POLLWRNORM);
}
if ((poll_events & (POLLIN | POLLRDNORM)) != 0) {
if (TAILQ_FIRST(&softc->snd_ccb_queue) != NULL
&& bufq_first(&softc->snd_buf_queue) == NULL)
revents |= poll_events & (POLLIN | POLLRDNORM);
}
if (softc->state != TARG_STATE_NORMAL)
revents |= POLLERR;
if (revents == 0) {
if (poll_events & (POLLOUT | POLLWRNORM))
selrecord(p, &softc->rcv_select);
if (poll_events & (POLLIN | POLLRDNORM))
selrecord(p, &softc->snd_select);
}
splx(s);
return (revents);
}
static int
targread(dev_t dev, struct uio *uio, int ioflag)
{
if (uio->uio_iovcnt == 0
|| uio->uio_iov->iov_len == 0) {
/* EOF */
struct cam_periph *periph;
struct targ_softc *softc;
u_int unit;
int s;
s = splcam();
unit = minor(dev);
periph = cam_extend_get(targperiphs, unit);
if (periph == NULL)
return (ENXIO);
softc = (struct targ_softc *)periph->softc;
softc->flags |= TARG_FLAG_SEND_EOF;
splx(s);
targrunqueue(periph, softc);
return (0);
}
return(physio(targstrategy, NULL, dev, 1, minphys, uio));
}
static int
targwrite(dev_t dev, struct uio *uio, int ioflag)
{
if (uio->uio_iovcnt == 0
|| uio->uio_iov->iov_len == 0) {
/* EOF */
struct cam_periph *periph;
struct targ_softc *softc;
u_int unit;
int s;
s = splcam();
unit = minor(dev);
periph = cam_extend_get(targperiphs, unit);
if (periph == NULL)
return (ENXIO);
softc = (struct targ_softc *)periph->softc;
softc->flags |= TARG_FLAG_RECEIVE_EOF;
splx(s);
targrunqueue(periph, softc);
return (0);
}
return(physio(targstrategy, NULL, dev, 0, minphys, uio));
}
/*
* Actually translate the requested transfer into one the physical driver
* can understand. The transfer is described by a buf and will include
* only one physical transfer.
*/
static void
targstrategy(struct buf *bp)
{
struct cam_periph *periph;
struct targ_softc *softc;
u_int unit;
int s;
unit = minor(bp->b_dev);
periph = cam_extend_get(targperiphs, unit);
if (periph == NULL) {
bp->b_error = ENXIO;
goto bad;
}
softc = (struct targ_softc *)periph->softc;
/*
* Mask interrupts so that the device cannot be invalidated until
* after we are in the queue. Otherwise, we might not properly
* clean up one of the buffers.
*/
s = splbio();
/*
* If there is an exception pending, error out
*/
if (softc->state != TARG_STATE_NORMAL) {
splx(s);
if (softc->state == TARG_STATE_EXCEPTION
&& (softc->exceptions & TARG_EXCEPT_DEVICE_INVALID) == 0)
bp->b_error = EBUSY;
else
bp->b_error = ENXIO;
goto bad;
}
/*
* Place it in the queue of buffers available for either
* SEND or RECEIVE commands.
*
*/
bp->b_resid = bp->b_bcount;
if ((bp->b_flags & B_READ) != 0) {
CAM_DEBUG(periph->path, CAM_DEBUG_SUBTRACE,
("Queued a SEND buffer\n"));
bufq_insert_tail(&softc->snd_buf_queue, bp);
} else {
CAM_DEBUG(periph->path, CAM_DEBUG_SUBTRACE,
("Queued a RECEIVE buffer\n"));
bufq_insert_tail(&softc->rcv_buf_queue, bp);
}
splx(s);
/*
* Attempt to use the new buffer to service any pending
* target commands.
*/
targrunqueue(periph, softc);
return;
bad:
bp->b_flags |= B_ERROR;
/*
* Correctly set the buf to indicate a completed xfer
*/
bp->b_resid = bp->b_bcount;
biodone(bp);
}
static void
targrunqueue(struct cam_periph *periph, struct targ_softc *softc)
{
struct ccb_queue *pending_queue;
struct ccb_accept_tio *atio;
struct buf_queue_head *bufq;
struct buf *bp;
struct targ_cmd_desc *desc;
struct ccb_hdr *ccbh;
int s;
s = splbio();
pending_queue = NULL;
bufq = NULL;
ccbh = NULL;
/* Only run one request at a time to maintain data ordering. */
if (softc->state != TARG_STATE_NORMAL
|| TAILQ_FIRST(&softc->work_queue) != NULL
|| TAILQ_FIRST(&softc->pending_queue) != NULL) {
splx(s);
return;
}
if (((bp = bufq_first(&softc->snd_buf_queue)) != NULL
|| (softc->flags & TARG_FLAG_SEND_EOF) != 0)
&& (ccbh = TAILQ_FIRST(&softc->snd_ccb_queue)) != NULL) {
if (bp == NULL)
softc->flags &= ~TARG_FLAG_SEND_EOF;
else {
CAM_DEBUG(periph->path, CAM_DEBUG_SUBTRACE,
("De-Queued a SEND buffer %ld\n",
bp->b_bcount));
}
bufq = &softc->snd_buf_queue;
pending_queue = &softc->snd_ccb_queue;
} else if (((bp = bufq_first(&softc->rcv_buf_queue)) != NULL
|| (softc->flags & TARG_FLAG_RECEIVE_EOF) != 0)
&& (ccbh = TAILQ_FIRST(&softc->rcv_ccb_queue)) != NULL) {
if (bp == NULL)
softc->flags &= ~TARG_FLAG_RECEIVE_EOF;
else {
CAM_DEBUG(periph->path, CAM_DEBUG_SUBTRACE,
("De-Queued a RECEIVE buffer %ld\n",
bp->b_bcount));
}
bufq = &softc->rcv_buf_queue;
pending_queue = &softc->rcv_ccb_queue;
}
if (pending_queue != NULL) {
/* Process a request */
atio = (struct ccb_accept_tio *)ccbh;
TAILQ_REMOVE(pending_queue, ccbh, periph_links.tqe);
desc = (struct targ_cmd_desc *)atio->ccb_h.ccb_descr;
desc->bp = bp;
if (bp == NULL) {
/* EOF */
desc->data = NULL;
desc->data_increment = 0;
desc->data_resid = 0;
atio->ccb_h.flags &= ~CAM_DIR_MASK;
atio->ccb_h.flags |= CAM_DIR_NONE;
} else {
bufq_remove(bufq, bp);
desc->data = &bp->b_data[bp->b_bcount - bp->b_resid];
desc->data_increment =
MIN(desc->data_resid, bp->b_resid);
}
CAM_DEBUG(periph->path, CAM_DEBUG_SUBTRACE,
("Buffer command: data %x: datacnt %d\n",
(intptr_t)desc->data, desc->data_increment));
TAILQ_INSERT_TAIL(&softc->work_queue, &atio->ccb_h,
periph_links.tqe);
}
if (TAILQ_FIRST(&softc->work_queue) != NULL) {
splx(s);
xpt_schedule(periph, /*XXX priority*/1);
} else
splx(s);
}
static void
targstart(struct cam_periph *periph, union ccb *start_ccb)
{
struct targ_softc *softc;
struct ccb_hdr *ccbh;
struct ccb_accept_tio *atio;
struct targ_cmd_desc *desc;
struct ccb_scsiio *csio;
ccb_flags flags;
int s;
softc = (struct targ_softc *)periph->softc;
s = splbio();
ccbh = TAILQ_FIRST(&softc->work_queue);
if (periph->immediate_priority <= periph->pinfo.priority) {
start_ccb->ccb_h.ccb_type = TARG_CCB_WAITING;
SLIST_INSERT_HEAD(&periph->ccb_list, &start_ccb->ccb_h,
periph_links.sle);
periph->immediate_priority = CAM_PRIORITY_NONE;
splx(s);
wakeup(&periph->ccb_list);
} else if (ccbh == NULL) {
splx(s);
xpt_release_ccb(start_ccb);
} else {
TAILQ_REMOVE(&softc->work_queue, ccbh, periph_links.tqe);
TAILQ_INSERT_HEAD(&softc->pending_queue, ccbh,
periph_links.tqe);
splx(s);
atio = (struct ccb_accept_tio*)ccbh;
desc = (struct targ_cmd_desc *)atio->ccb_h.ccb_descr;
/* Is this a tagged request? */
flags = atio->ccb_h.flags & (CAM_TAG_ACTION_VALID|CAM_DIR_MASK);
/*
* If we are done with the transaction, tell the
* controller to send status and perform a CMD_CMPLT.
*/
if (desc->data_resid == desc->data_increment)
flags |= CAM_SEND_STATUS;
csio = &start_ccb->csio;
cam_fill_ctio(csio,
/*retries*/2,
targdone,
flags,
/*tag_action*/MSG_SIMPLE_Q_TAG,
atio->tag_id,
atio->init_id,
desc->status,
/*data_ptr*/desc->data_increment == 0
? NULL : desc->data,
/*dxfer_len*/desc->data_increment,
/*timeout*/desc->timeout);
start_ccb->ccb_h.ccb_type = TARG_CCB_WORKQ;
start_ccb->ccb_h.ccb_atio = atio;
CAM_DEBUG(periph->path, CAM_DEBUG_SUBTRACE,
("Sending a CTIO\n"));
xpt_action(start_ccb);
s = splbio();
ccbh = TAILQ_FIRST(&softc->work_queue);
splx(s);
}
if (ccbh != NULL)
targrunqueue(periph, softc);
}
static void
targdone(struct cam_periph *periph, union ccb *done_ccb)
{
struct targ_softc *softc;
softc = (struct targ_softc *)periph->softc;
if (done_ccb->ccb_h.ccb_type == TARG_CCB_WAITING) {
/* Caller will release the CCB */
wakeup(&done_ccb->ccb_h.cbfcnp);
return;
}
switch (done_ccb->ccb_h.func_code) {
case XPT_ACCEPT_TARGET_IO:
{
struct ccb_accept_tio *atio;
struct targ_cmd_desc *descr;
struct initiator_state *istate;
u_int8_t *cdb;
atio = &done_ccb->atio;
descr = (struct targ_cmd_desc*)atio->ccb_h.ccb_descr;
istate = &softc->istate[atio->init_id];
cdb = atio->cdb_io.cdb_bytes;
if (softc->state == TARG_STATE_TEARDOWN
|| atio->ccb_h.status == CAM_REQ_ABORTED) {
printf("Freed an accept tio\n");
freedescr(descr);
free(done_ccb, M_DEVBUF);
return;
}
if (istate->pending_ca == 0
&& istate->pending_ua != 0
&& cdb[0] != INQUIRY) {
/* Pending UA, tell initiator */
/* Direction is always relative to the initator */
istate->pending_ca = CA_UNIT_ATTN;
atio->ccb_h.flags &= ~CAM_DIR_MASK;
atio->ccb_h.flags |= CAM_DIR_NONE;
descr->data_resid = 0;
descr->data_increment = 0;
descr->timeout = 5 * 1000;
descr->status = SCSI_STATUS_CHECK_COND;
} else {
/*
* Save the current CA and UA status so
* they can be used by this command.
*/
ua_types pending_ua;
ca_types pending_ca;
pending_ua = istate->pending_ua;
pending_ca = istate->pending_ca;
/*
* As per the SCSI2 spec, any command that occurs
* after a CA is reported, clears the CA. If the
* command is not an inquiry, we are also supposed
* to clear the UA condition, if any, that caused
* the CA to occur assuming the UA is not a
* persistant state.
*/
istate->pending_ca = CA_NONE;
if ((pending_ca
& (CA_CMD_SENSE|CA_UNIT_ATTN)) == CA_UNIT_ATTN
&& cdb[0] != INQUIRY)
istate->pending_ua = UA_NONE;
/*
* Determine the type of incoming command and
* setup our buffer for a response.
*/
switch (cdb[0]) {
case INQUIRY:
{
struct scsi_inquiry *inq;
struct scsi_sense_data *sense;
inq = (struct scsi_inquiry *)cdb;
sense = &istate->sense_data;
CAM_DEBUG(periph->path, CAM_DEBUG_SUBTRACE,
("Saw an inquiry!\n"));
/*
* Validate the command. We don't
* support any VPD pages, so complain
* if EVPD is set.
*/
if ((inq->byte2 & SI_EVPD) != 0
|| inq->page_code != 0) {
istate->pending_ca = CA_CMD_SENSE;
atio->ccb_h.flags &= ~CAM_DIR_MASK;
atio->ccb_h.flags |= CAM_DIR_NONE;
descr->data_resid = 0;
descr->data_increment = 0;
descr->status = SCSI_STATUS_CHECK_COND;
fill_sense(sense,
SSD_CURRENT_ERROR,
SSD_KEY_ILLEGAL_REQUEST,
/*asc*/0x24, /*ascq*/0x00);
sense->extra_len =
offsetof(struct scsi_sense_data,
extra_bytes)
- offsetof(struct scsi_sense_data,
extra_len);
}
if ((inq->byte2 & SI_EVPD) != 0) {
sense->sense_key_spec[0] =
SSD_SCS_VALID|SSD_FIELDPTR_CMD
|SSD_BITPTR_VALID| /*bit value*/1;
sense->sense_key_spec[1] = 0;
sense->sense_key_spec[2] =
offsetof(struct scsi_inquiry,
byte2);
break;
} else if (inq->page_code != 0) {
sense->sense_key_spec[0] =
SSD_SCS_VALID|SSD_FIELDPTR_CMD;
sense->sense_key_spec[1] = 0;
sense->sense_key_spec[2] =
offsetof(struct scsi_inquiry,
page_code);
break;
}
/*
* Direction is always relative
* to the initator.
*/
atio->ccb_h.flags &= ~CAM_DIR_MASK;
atio->ccb_h.flags |= CAM_DIR_IN;
descr->data = softc->inq_data;
descr->data_resid = MIN(softc->inq_data_len,
inq->length);
descr->data_increment = descr->data_resid;
descr->timeout = 5 * 1000;
descr->status = SCSI_STATUS_OK;
break;
}
case TEST_UNIT_READY:
atio->ccb_h.flags &= ~CAM_DIR_MASK;
atio->ccb_h.flags |= CAM_DIR_NONE;
descr->data_resid = 0;
descr->data_increment = 0;
descr->status = SCSI_STATUS_OK;
break;
case REQUEST_SENSE:
{
struct scsi_request_sense *rsense;
struct scsi_sense_data *sense;
rsense = (struct scsi_request_sense *)cdb;
sense = &istate->sense_data;
if (pending_ca == 0) {
fill_sense(sense, SSD_CURRENT_ERROR,
SSD_KEY_NO_SENSE, 0x00,
0x00);
CAM_DEBUG(periph->path,
CAM_DEBUG_SUBTRACE,
("No pending CA!\n"));
} else if (pending_ca == CA_UNIT_ATTN) {
u_int ascq;
if (pending_ua == UA_POWER_ON)
ascq = 0x1;
else
ascq = 0x2;
fill_sense(sense, SSD_CURRENT_ERROR,
SSD_KEY_UNIT_ATTENTION,
0x29, ascq);
CAM_DEBUG(periph->path,
CAM_DEBUG_SUBTRACE,
("Pending UA!\n"));
}
/*
* Direction is always relative
* to the initator.
*/
atio->ccb_h.flags &= ~CAM_DIR_MASK;
atio->ccb_h.flags |= CAM_DIR_IN;
descr->data = sense;
descr->data_resid =
offsetof(struct scsi_sense_data,
extra_len)
+ sense->extra_len;
descr->data_resid = MIN(descr->data_resid,
rsense->length);
descr->data_increment = descr->data_resid;
descr->timeout = 5 * 1000;
descr->status = SCSI_STATUS_OK;
break;
}
case RECEIVE:
case SEND:
{
struct scsi_send_receive *sr;
sr = (struct scsi_send_receive *)cdb;
/*
* Direction is always relative
* to the initator.
*/
atio->ccb_h.flags &= ~CAM_DIR_MASK;
if (cdb[0] == SEND) {
atio->ccb_h.flags |= CAM_DIR_OUT;
CAM_DEBUG(periph->path,
CAM_DEBUG_SUBTRACE,
("Saw a SEND!\n"));
atio->ccb_h.flags |= CAM_DIR_OUT;
TAILQ_INSERT_TAIL(&softc->snd_ccb_queue,
&atio->ccb_h,
periph_links.tqe);
selwakeup(&softc->snd_select);
} else {
atio->ccb_h.flags |= CAM_DIR_IN;
CAM_DEBUG(periph->path,
CAM_DEBUG_SUBTRACE,
("Saw a RECEIVE!\n"));
TAILQ_INSERT_TAIL(&softc->rcv_ccb_queue,
&atio->ccb_h,
periph_links.tqe);
selwakeup(&softc->rcv_select);
}
descr->data_resid = scsi_3btoul(sr->xfer_len);
descr->timeout = 5 * 1000;
descr->status = SCSI_STATUS_OK;
/*
* Attempt to satisfy this request with
* a user buffer.
*/
targrunqueue(periph, softc);
return;
}
default:
/*
* Queue for consumption by our userland
* counterpart and transition to the exception
* state.
*/
TAILQ_INSERT_TAIL(&softc->unknown_atio_queue,
&atio->ccb_h,
periph_links.tqe);
softc->exceptions |= TARG_EXCEPT_UNKNOWN_ATIO;
targfireexception(periph, softc);
return;
}
}
/* Queue us up to receive a Continue Target I/O ccb. */
TAILQ_INSERT_TAIL(&softc->work_queue, &atio->ccb_h,
periph_links.tqe);
xpt_schedule(periph, /*priority*/1);
break;
}
case XPT_CONT_TARGET_IO:
{
struct ccb_accept_tio *atio;
struct targ_cmd_desc *desc;
struct buf *bp;
CAM_DEBUG(periph->path, CAM_DEBUG_SUBTRACE,
("Received completed CTIO\n"));
atio = (struct ccb_accept_tio*)done_ccb->ccb_h.ccb_atio;
desc = (struct targ_cmd_desc *)atio->ccb_h.ccb_descr;
TAILQ_REMOVE(&softc->pending_queue, &atio->ccb_h,
periph_links.tqe);
/* XXX Check for errors */
desc->data_resid -= desc->data_increment;
if ((bp = desc->bp) != NULL) {
bp->b_resid -= desc->data_increment;
bp->b_error = 0;
CAM_DEBUG(periph->path, CAM_DEBUG_SUBTRACE,
("Buffer I/O Completed - Resid %ld:%d\n",
bp->b_resid, desc->data_resid));
/*
* Send the buffer back to the client if
* either the command has completed or all
* buffer space has been consumed.
*/
if (desc->data_resid == 0
|| bp->b_resid == 0) {
if (bp->b_resid != 0)
/* Short transfer */
bp->b_flags |= B_ERROR;
CAM_DEBUG(periph->path, CAM_DEBUG_SUBTRACE,
("Completing a buffer\n"));
biodone(bp);
desc->bp = NULL;
}
}
xpt_release_ccb(done_ccb);
if (softc->state != TARG_STATE_TEARDOWN) {
if (desc->data_resid == 0) {
/*
* Send the original accept TIO back to the
* controller to handle more work.
*/
CAM_DEBUG(periph->path, CAM_DEBUG_SUBTRACE,
("Returning ATIO to target\n"));
xpt_action((union ccb *)atio);
break;
}
/* Queue us up for another buffer */
if (atio->cdb_io.cdb_bytes[0] == SEND) {
if (desc->bp != NULL)
TAILQ_INSERT_HEAD(
&softc->snd_buf_queue.queue,
bp, b_act);
TAILQ_INSERT_HEAD(&softc->snd_ccb_queue,
&atio->ccb_h,
periph_links.tqe);
} else {
if (desc->bp != NULL)
TAILQ_INSERT_HEAD(
&softc->rcv_buf_queue.queue,
bp, b_act);
TAILQ_INSERT_HEAD(&softc->rcv_ccb_queue,
&atio->ccb_h,
periph_links.tqe);
}
desc->bp = NULL;
targrunqueue(periph, softc);
} else {
if (desc->bp != NULL) {
bp->b_flags |= B_ERROR;
bp->b_error = ENXIO;
biodone(bp);
}
freedescr(desc);
free(atio, M_DEVBUF);
}
break;
}
case XPT_IMMED_NOTIFY:
{
if (softc->state == TARG_STATE_TEARDOWN
|| done_ccb->ccb_h.status == CAM_REQ_ABORTED) {
printf("Freed an immediate notify\n");
free(done_ccb, M_DEVBUF);
}
break;
}
}
}
/*
* Transition to the exception state and notify our symbiotic
* userland process of the change.
*/
static void
targfireexception(struct cam_periph *periph, struct targ_softc *softc)
{
/*
* return all pending buffers with short read/write status so our
* process unblocks, and do a selwakeup on any process queued
* waiting for reads or writes. When the selwakeup is performed,
* the waking process will wakeup, call our poll routine again,
* and pick up the exception.
*/
struct buf *bp;
if (softc->state != TARG_STATE_NORMAL)
/* Already either tearing down or in exception state */
return;
softc->state = TARG_STATE_EXCEPTION;
while ((bp = bufq_first(&softc->snd_buf_queue)) != NULL) {
bufq_remove(&softc->snd_buf_queue, bp);
bp->b_flags |= B_ERROR;
biodone(bp);
}
while ((bp = bufq_first(&softc->rcv_buf_queue)) != NULL) {
bufq_remove(&softc->snd_buf_queue, bp);
bp->b_flags |= B_ERROR;
biodone(bp);
}
selwakeup(&softc->snd_select);
selwakeup(&softc->rcv_select);
}
static int
targerror(union ccb *ccb, u_int32_t cam_flags, u_int32_t sense_flags)
{
return 0;
}
static struct targ_cmd_desc*
allocdescr()
{
struct targ_cmd_desc* descr;
/* Allocate the targ_descr structure */
descr = (struct targ_cmd_desc *)malloc(sizeof(*descr),
M_DEVBUF, M_NOWAIT);
if (descr == NULL)
return (NULL);
bzero(descr, sizeof(*descr));
/* Allocate buffer backing store */
descr->backing_store = malloc(MAX_BUF_SIZE, M_DEVBUF, M_NOWAIT);
if (descr->backing_store == NULL) {
free(descr, M_DEVBUF);
return (NULL);
}
descr->max_size = MAX_BUF_SIZE;
return (descr);
}
static void
freedescr(struct targ_cmd_desc *descr)
{
free(descr->backing_store, M_DEVBUF);
free(descr, M_DEVBUF);
}
static void
fill_sense(struct scsi_sense_data *sense, u_int error_code, u_int sense_key,
u_int asc, u_int ascq)
{
bzero(sense, sizeof(*sense));
sense->error_code = error_code;
sense->flags = sense_key;
sense->add_sense_code = asc;
sense->add_sense_code_qual = ascq;
sense->extra_len = offsetof(struct scsi_sense_data, fru)
- offsetof(struct scsi_sense_data, extra_len);
}
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