source: rtems-libbsd/rtemsbsd/rtems/rtems-kernel-cam.c

/**
 * @file
 *
 * @ingroup rtems_bsd_rtems
 *
 * @brief TODO.
 */

/*
 * Copyright (c) 2009-2012 embedded brains GmbH.  
 * All rights reserved.
 *
 *  embedded brains GmbH
 *  Obere Lagerstr. 30
 *  82178 Puchheim
 *  Germany
 *  <rtems@embedded-brains.de>
 *
 * 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 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 <machine/rtems-bsd-kernel-space.h>
#include <machine/rtems-bsd-support.h>

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/condvar.h>

#include <cam/cam.h>
#include <cam/cam_ccb.h>
#include <cam/cam_sim.h>
#include <cam/cam_xpt.h>
#include <cam/cam_xpt_sim.h>
#include <cam/cam_debug.h>

#include <cam/scsi/scsi_all.h>

#include <rtems/media.h>
#include <rtems/libio.h>
#include <rtems/diskdevs.h>

#define BSD_CAM_DEVQ_DUMMY ((struct cam_devq *) 0xdeadbeef)

#define BSD_SCSI_TAG 0

#define BSD_SCSI_RETRIES 4

#define BSD_SCSI_TIMEOUT (60 * 1000)

#define BSD_SCSI_MIN_COMMAND_SIZE 10

MALLOC_DEFINE(M_CAMSIM, "CAM SIM", "CAM SIM buffers");

static void
rtems_bsd_sim_set_state(struct cam_sim *sim, enum bsd_sim_state state)
{
        sim->state = state;
}

static void
rtems_bsd_sim_set_state_and_notify(struct cam_sim *sim, enum bsd_sim_state state)
{
        sim->state = state;
        cv_broadcast(&sim->state_changed);
}

static void
rtems_bsd_sim_wait_for_state(struct cam_sim *sim, enum bsd_sim_state state)
{
        while (sim->state != state) {
                cv_wait(&sim->state_changed, sim->mtx);
        }
}

static void
rtems_bsd_sim_wait_for_state_and_cancel_ccb(struct cam_sim *sim, enum bsd_sim_state state)
{
        while (sim->state != state) {
                if (sim->state != BSD_SIM_BUSY) {
                        cv_wait(&sim->state_changed, sim->mtx);
                } else {
                        sim->ccb.ccb_h.status = CAM_SEL_TIMEOUT;
                        (*sim->ccb.ccb_h.cbfcnp)(NULL, &sim->ccb);
                }
        }
}

static void
rtems_bsd_ccb_callback(struct cam_periph *periph, union ccb *ccb)
{
        struct cam_sim *sim = ccb->ccb_h.sim;

        BSD_ASSERT(periph == NULL && sim->state == BSD_SIM_INIT_BUSY);

        rtems_bsd_sim_set_state_and_notify(sim, BSD_SIM_INIT_READY);
}

static rtems_status_code
rtems_bsd_ccb_action(union ccb *ccb)
{
        rtems_status_code sc = RTEMS_SUCCESSFUL;
        struct cam_sim *sim = ccb->ccb_h.sim;

        mtx_lock(sim->mtx);

        BSD_ASSERT(sim->state == BSD_SIM_INIT);
        rtems_bsd_sim_set_state(sim, BSD_SIM_INIT_BUSY);
        (*sim->sim_action)(sim, ccb);
        rtems_bsd_sim_wait_for_state(sim, BSD_SIM_INIT_READY);
        if (ccb->ccb_h.status != CAM_REQ_CMP) {
                sc = RTEMS_IO_ERROR;
        }
        rtems_bsd_sim_set_state(sim, BSD_SIM_INIT);

        mtx_unlock(sim->mtx);

        return sc;
}

static rtems_status_code
rtems_bsd_scsi_inquiry(union ccb *ccb, struct scsi_inquiry_data *inq_data)
{
        memset(inq_data, 0, sizeof(*inq_data));

        scsi_inquiry(
                &ccb->csio,
                BSD_SCSI_RETRIES,
                rtems_bsd_ccb_callback,
                BSD_SCSI_TAG,
                (u_int8_t *) inq_data,
                SHORT_INQUIRY_LENGTH,
                FALSE,
                0,
                SSD_MIN_SIZE,
                BSD_SCSI_TIMEOUT
        );

        return rtems_bsd_ccb_action(ccb);
}

static rtems_status_code
rtems_bsd_scsi_test_unit_ready(union ccb *ccb)
{
        scsi_test_unit_ready(
                &ccb->csio,
                BSD_SCSI_RETRIES,
                rtems_bsd_ccb_callback,
                BSD_SCSI_TAG,
                SSD_FULL_SIZE,
                BSD_SCSI_TIMEOUT
        );

        return rtems_bsd_ccb_action(ccb);
}

static rtems_status_code
rtems_bsd_scsi_read_capacity(union ccb *ccb, uint32_t *block_count, uint32_t *block_size)
{
        rtems_status_code sc = RTEMS_SUCCESSFUL;
        struct scsi_read_capacity_data rdcap;

        memset(&rdcap, 0, sizeof(rdcap));

        scsi_read_capacity(
                &ccb->csio,
                BSD_SCSI_RETRIES,
                rtems_bsd_ccb_callback,
                BSD_SCSI_TAG,
                &rdcap,
                SSD_FULL_SIZE,
                BSD_SCSI_TIMEOUT
        );

        sc = rtems_bsd_ccb_action(ccb);
        if (sc != RTEMS_SUCCESSFUL) {
                return RTEMS_IO_ERROR;
        }

        *block_size = scsi_4btoul(rdcap.length);
        *block_count = scsi_4btoul(rdcap.addr) + 1;

        return RTEMS_SUCCESSFUL;
}

static void
rtems_bsd_csio_callback(struct cam_periph *periph, union ccb *ccb)
{
        rtems_status_code sc = RTEMS_SUCCESSFUL;
        bool done = false;
        struct cam_sim *sim = ccb->ccb_h.sim;

        BSD_ASSERT(periph == NULL && sim->state == BSD_SIM_BUSY);

        if (ccb->ccb_h.status == CAM_REQ_CMP) {
                rtems_blkdev_sg_buffer *sg = ccb->csio.sg_current;

                if (sg != ccb->csio.sg_end) {
                        scsi_read_write(
                                &ccb->csio,
                                BSD_SCSI_RETRIES,
                                rtems_bsd_csio_callback,
                                BSD_SCSI_TAG,
                                ccb->csio.readop,
                                0,
                                BSD_SCSI_MIN_COMMAND_SIZE,
                                sg->block,
                                sg->length / 512, /* FIXME */
                                sg->buffer,
                                sg->length,
                                SSD_FULL_SIZE,
                                BSD_SCSI_TIMEOUT
                        );
                        ccb->csio.sg_current = sg + 1;
                        (*sim->sim_action)(sim, ccb);
                } else {
                        done = true;
                }
        } else if (ccb->ccb_h.status == CAM_SEL_TIMEOUT) {
                sc = RTEMS_UNSATISFIED;
                done = true;
        } else {
                sc = RTEMS_IO_ERROR;
                done = true;
        }

        if (done) {
                rtems_blkdev_request_done(ccb->csio.req, sc);
                rtems_bsd_sim_set_state_and_notify(sim, BSD_SIM_IDLE);
        }
}

static int rtems_bsd_sim_disk_read_write(struct cam_sim *sim, rtems_blkdev_request *req)
{
        mtx_lock(sim->mtx);

        rtems_bsd_sim_wait_for_state(sim, BSD_SIM_IDLE);
        rtems_bsd_sim_set_state(sim, BSD_SIM_BUSY);

        switch (req->req) {
                case RTEMS_BLKDEV_REQ_READ:
                        sim->ccb.csio.readop = TRUE;
                        break;
                case RTEMS_BLKDEV_REQ_WRITE:
                        sim->ccb.csio.readop = FALSE;
                        break;
                default:
                        mtx_unlock(sim->mtx);
                        return -1;
        }

        sim->ccb.csio.sg_current = req->bufs;
        sim->ccb.csio.sg_end = req->bufs + req->bufnum;
        sim->ccb.csio.req = req;

        sim->ccb.ccb_h.status = CAM_REQ_CMP;

        rtems_bsd_csio_callback(NULL, &sim->ccb);

        mtx_unlock(sim->mtx);

        return 0;
}

static int rtems_bsd_sim_disk_ioctl(rtems_disk_device *dd, uint32_t req, void *arg)
{
        struct cam_sim *sim = rtems_disk_get_driver_data(dd);

        if (req == RTEMS_BLKIO_REQUEST) {
                rtems_blkdev_request *r = arg;

                return rtems_bsd_sim_disk_read_write(sim, r);
        } else if (req == RTEMS_BLKIO_DELETED) {
                mtx_lock(sim->mtx);

                free(sim->disk, M_RTEMS_HEAP);
                sim->disk = NULL;
                rtems_bsd_sim_set_state_and_notify(sim, BSD_SIM_DELETED);

                mtx_unlock(sim->mtx);

                return 0;
        } else {
                return rtems_blkdev_ioctl(dd, req, arg);
        }
}

static void
rtems_bsd_sim_disk_initialized(struct cam_sim *sim, char *disk)
{
        mtx_lock(sim->mtx);

        sim->disk = disk;
        rtems_bsd_sim_set_state_and_notify(sim, BSD_SIM_IDLE);

        mtx_unlock(sim->mtx);
}

static rtems_status_code
rtems_bsd_sim_attach_worker(rtems_media_state state, const char *src, char **dest, void *arg)
{
        rtems_status_code sc = RTEMS_SUCCESSFUL;
        struct cam_sim *sim = arg;
        char *disk = NULL;

        if (state == RTEMS_MEDIA_STATE_READY) {
                unsigned retries = 0;

                struct scsi_inquiry_data inq_data;
                uint32_t block_count = 0;
                uint32_t block_size = 0;

                disk = rtems_media_create_path("/dev", src, cam_sim_unit(sim));
                if (disk == NULL) {
                        BSD_PRINTF("OOPS: create path failed\n");
                        goto error;
                }

                sc = rtems_bsd_scsi_inquiry(&sim->ccb, &inq_data);
                if (sc == RTEMS_SUCCESSFUL) {
                        scsi_print_inquiry(&inq_data);
                } else {
                        BSD_PRINTF("OOPS: inquiry failed\n");
                }

                for (retries = 0; retries <= 3; ++retries) {
                        sc = rtems_bsd_scsi_test_unit_ready(&sim->ccb);
                        if (sc == RTEMS_SUCCESSFUL) {
                                break;
                        }
                }
                if (sc != RTEMS_SUCCESSFUL) {
                        BSD_PRINTF("OOPS: test unit ready failed\n");
                }

                for (retries = 0; retries <= 3; ++retries) {
                        sc = rtems_bsd_scsi_read_capacity(&sim->ccb, &block_count, &block_size);
                        if (sc == RTEMS_SUCCESSFUL) {
                                break;
                        }
                }
                if (sc != RTEMS_SUCCESSFUL) {
                        BSD_PRINTF("OOPS: read capacity failed\n");
                        goto error;
                }

                BSD_PRINTF("read capacity: block count %u, block size %u\n", block_count, block_size);

                sc = rtems_blkdev_create(disk, block_size, block_count, rtems_bsd_sim_disk_ioctl, sim);
                if (sc != RTEMS_SUCCESSFUL) {
                        goto error;
                }

                /* FIXME */
#if 0
                rtems_disk_device *dd = rtems_disk_obtain(dev);
                dd->block_size *= 64;
                rtems_disk_release(dd);
#endif

                rtems_bsd_sim_disk_initialized(sim, disk);

                *dest = strdup(disk, M_RTEMS_HEAP);
        }

        return RTEMS_SUCCESSFUL;

error:

        free(disk, M_RTEMS_HEAP);

        rtems_bsd_sim_disk_initialized(sim, NULL);

        return RTEMS_IO_ERROR;
}

struct cam_sim *
cam_sim_alloc(
        sim_action_func sim_action,
        sim_poll_func sim_poll,
        const char *sim_name,
        void *softc,
        u_int32_t unit,
        struct mtx *mtx,
        int max_dev_transactions,
        int max_tagged_dev_transactions,
        struct cam_devq *queue
)
{
        rtems_status_code sc = RTEMS_SUCCESSFUL;
        struct cam_sim *sim = NULL;

        if (mtx == NULL) {
                return NULL;
        }

        sim = malloc(sizeof(*sim), M_CAMSIM, M_NOWAIT | M_ZERO);
        if (sim == NULL) {
                return NULL;
        }

        sim->sim_action = sim_action;
        sim->sim_poll = sim_poll;
        sim->sim_name = sim_name;
        sim->softc = softc;
        sim->mtx = mtx;
        sim->unit_number = unit;
        sim->ccb.ccb_h.sim = sim;

        cv_init(&sim->state_changed, "SIM state changed");

        sc = rtems_media_server_disk_attach(sim_name, rtems_bsd_sim_attach_worker, sim);
        BSD_ASSERT_SC(sc);

        return sim;
}

void
cam_sim_free(struct cam_sim *sim, int free_devq)
{
        rtems_status_code sc = RTEMS_SUCCESSFUL;

        /*
         * The umass_detach() cancels all transfers via
         * usbd_transfer_unsetup().  This prevents also the start of new
         * transfers since the transfer descriptors will be removed.  Started
         * transfers that are not in the transferring state will be canceled
         * and the callbacks will be not called.  Thus it is necessary to do
         * this here if we are in the BUSY state.
         */
        rtems_bsd_sim_wait_for_state_and_cancel_ccb(sim, BSD_SIM_IDLE);

        if (sim->disk != NULL) {
                sc = rtems_media_server_disk_detach(sim->disk);
                BSD_ASSERT_SC(sc);

                rtems_bsd_sim_wait_for_state(sim, BSD_SIM_DELETED);
        }

        cv_destroy(&sim->state_changed);
        free(sim, M_CAMSIM);
}

struct cam_devq *
cam_simq_alloc(u_int32_t max_sim_transactions)
{
        return BSD_CAM_DEVQ_DUMMY;
}

void
cam_simq_free(struct cam_devq *devq)
{
        BSD_ASSERT(devq == BSD_CAM_DEVQ_DUMMY);
}

void
xpt_done(union ccb *done_ccb)
{
        (*done_ccb->ccb_h.cbfcnp)(NULL, done_ccb);
}

int32_t
xpt_bus_register(struct cam_sim *sim, device_t parent, u_int32_t bus)
{
        /*
         * We ignore this bus stuff completely.  This is easier than removing
         * the calls from "umass.c".
         */

        return CAM_SUCCESS;
}

int32_t
xpt_bus_deregister(path_id_t pathid)
{
        /*
         * We ignore this bus stuff completely.  This is easier than removing
         * the calls from "umass.c".
         */

        return CAM_REQ_CMP;
}