/*
* Copyright 2002/03, Thomas Kurschel. All rights reserved.
* Distributed under the terms of the MIT License.
*/
/*
Part of Open SCSI bus manager
Bus node layer.
Whenever a controller driver publishes a new controller, a new SCSI bus
for public and internal use is registered in turn. After that, this
bus is told to rescan for devices. For each device, there is a
device registered for peripheral drivers. (see devices.c)
*/
#include "scsi_internal.h"
#include <string.h>
#include <malloc.h>
// bus service should hurry up a bit - good controllers don't take much time
// but are very happy to be busy; don't make it realtime though as we
// don't really need that but would risk to steel processing power of
// realtime-demanding threads
#define BUS_SERVICE_PRIORITY B_URGENT_DISPLAY_PRIORITY
/** implementation of service thread:
* it handles DPC and pending requests
*/
static void
scsi_do_service(scsi_bus_info *bus)
{
while (true) {
SHOW_FLOW0( 3, "" );
// handle DPCs first as they are more urgent
if (scsi_check_exec_dpc(bus))
continue;
if (scsi_check_exec_service(bus))
continue;
break;
}
}
/** main loop of service thread */
static int32
scsi_service_threadproc(void *arg)
{
scsi_bus_info *bus = (scsi_bus_info *)arg;
int32 processed_notifications = 0;
SHOW_FLOW(3, "bus = %p", bus);
while (true) {
// we handle multiple requests in scsi_do_service at once;
// to save time, we will acquire all notifications that are sent
// up to now at once.
// (Sadly, there is no "set semaphore to zero" function, so this
// is a poor-man emulation)
acquire_sem_etc(bus->start_service, processed_notifications + 1, 0, 0);
SHOW_FLOW0( 3, "1" );
if (bus->shutting_down)
break;
// get number of notifications _before_ servicing to make sure no new
// notifications are sent after do_service()
get_sem_count(bus->start_service, &processed_notifications);
scsi_do_service(bus);
}
return 0;
}
static scsi_bus_info *
scsi_create_bus(device_node *node, uint8 path_id)
{
scsi_bus_info *bus;
int res;
SHOW_FLOW0(3, "");
bus = (scsi_bus_info *)malloc(sizeof(*bus));
if (bus == NULL)
return NULL;
memset(bus, 0, sizeof(*bus));
bus->path_id = path_id;
if (pnp->get_attr_uint32(node, SCSI_DEVICE_MAX_TARGET_COUNT, &bus->max_target_count, true) != B_OK)
bus->max_target_count = MAX_TARGET_ID + 1;
if (pnp->get_attr_uint32(node, SCSI_DEVICE_MAX_LUN_COUNT, &bus->max_lun_count, true) != B_OK)
bus->max_lun_count = MAX_LUN_ID + 1;
// our scsi_ccb only has a uchar for target_id
if (bus->max_target_count > 256)
bus->max_target_count = 256;
// our scsi_ccb only has a uchar for target_lun
if (bus->max_lun_count > 256)
bus->max_lun_count = 256;
bus->node = node;
bus->lock_count = bus->blocked[0] = bus->blocked[1] = 0;
bus->sim_overflow = 0;
bus->shutting_down = false;
bus->waiting_devices = NULL;
//bus->resubmitted_req = NULL;
bus->dpc_list = NULL;
if ((bus->scan_lun_lock = create_sem(1, "scsi_scan_lun_lock")) < 0) {
res = bus->scan_lun_lock;
goto err6;
}
bus->start_service = create_sem(0, "scsi_start_service");
if (bus->start_service < 0) {
res = bus->start_service;
goto err4;
}
res = INIT_BEN(&bus->mutex, "scsi_bus_mutex");
if (res < B_OK)
goto err3;
spinlock_irq_init(&bus->dpc_lock);
res = scsi_init_ccb_alloc(bus);
if (res < B_OK)
goto err2;
bus->service_thread = spawn_kernel_thread(scsi_service_threadproc,
"scsi_bus_service", BUS_SERVICE_PRIORITY, bus);
if (bus->service_thread < 0) {
res = bus->service_thread;
goto err1;
}
resume_thread(bus->service_thread);
return bus;
err1:
scsi_uninit_ccb_alloc(bus);
err2:
DELETE_BEN(&bus->mutex);
err3:
delete_sem(bus->start_service);
err4:
delete_sem(bus->scan_lun_lock);
err6:
free(bus);
return NULL;
}
static status_t
scsi_destroy_bus(scsi_bus_info *bus)
{
int32 retcode;
// noone is using this bus now, time to clean it up
bus->shutting_down = true;
release_sem(bus->start_service);
wait_for_thread(bus->service_thread, &retcode);
delete_sem(bus->start_service);
DELETE_BEN(&bus->mutex);
delete_sem(bus->scan_lun_lock);
scsi_uninit_ccb_alloc(bus);
return B_OK;
}
static status_t
scsi_init_bus(device_node *node, void **cookie)
{
uint8 path_id;
scsi_bus_info *bus;
status_t res;
SHOW_FLOW0( 3, "" );
if (pnp->get_attr_uint8(node, SCSI_BUS_PATH_ID_ITEM, &path_id, false) != B_OK)
return B_ERROR;
bus = scsi_create_bus(node, path_id);
if (bus == NULL)
return B_NO_MEMORY;
// extract controller/protocoll restrictions from node
if (pnp->get_attr_uint32(node, B_DMA_ALIGNMENT, &bus->dma_params.alignment,
true) != B_OK)
bus->dma_params.alignment = 0;
if (pnp->get_attr_uint32(node, B_DMA_MAX_TRANSFER_BLOCKS,
&bus->dma_params.max_blocks, true) != B_OK)
bus->dma_params.max_blocks = 0xffffffff;
if (pnp->get_attr_uint32(node, B_DMA_BOUNDARY,
&bus->dma_params.dma_boundary, true) != B_OK)
bus->dma_params.dma_boundary = ~0;
if (pnp->get_attr_uint32(node, B_DMA_MAX_SEGMENT_BLOCKS,
&bus->dma_params.max_sg_block_size, true) != B_OK)
bus->dma_params.max_sg_block_size = 0xffffffff;
if (pnp->get_attr_uint32(node, B_DMA_MAX_SEGMENT_COUNT,
&bus->dma_params.max_sg_blocks, true) != B_OK)
bus->dma_params.max_sg_blocks = ~0;
// do some sanity check:
bus->dma_params.max_sg_block_size &= ~bus->dma_params.alignment;
if (bus->dma_params.alignment > B_PAGE_SIZE) {
SHOW_ERROR(0, "Alignment (0x%" B_PRIx32 ") must be less then "
"B_PAGE_SIZE", bus->dma_params.alignment);
res = B_ERROR;
goto err;
}
if (bus->dma_params.max_sg_block_size < 1) {
SHOW_ERROR(0, "Max s/g block size (0x%" B_PRIx32 ") is too small",
bus->dma_params.max_sg_block_size);
res = B_ERROR;
goto err;
}
if (bus->dma_params.dma_boundary < B_PAGE_SIZE - 1) {
SHOW_ERROR(0, "DMA boundary (0x%" B_PRIx32 ") must be at least "
"B_PAGE_SIZE", bus->dma_params.dma_boundary);
res = B_ERROR;
goto err;
}
if (bus->dma_params.max_blocks < 1 || bus->dma_params.max_sg_blocks < 1) {
SHOW_ERROR(0, "Max blocks (%" B_PRIu32 ") and max s/g blocks (%"
B_PRIu32 ") must be at least 1", bus->dma_params.max_blocks,
bus->dma_params.max_sg_blocks);
res = B_ERROR;
goto err;
}
{
device_node *parent = pnp->get_parent_node(node);
pnp->get_driver(parent, (driver_module_info **)&bus->interface,
(void **)&bus->sim_cookie);
pnp->put_node(parent);
bus->interface->set_scsi_bus(bus->sim_cookie, bus);
}
// cache inquiry data
scsi_inquiry_path(bus, &bus->inquiry_data);
// get max. number of commands on bus
bus->left_slots = bus->inquiry_data.hba_queue_size;
SHOW_FLOW( 3, "Bus has %d slots", bus->left_slots );
*cookie = bus;
return B_OK;
err:
scsi_destroy_bus(bus);
return res;
}
static void
scsi_uninit_bus(scsi_bus_info *bus)
{
scsi_destroy_bus(bus);
}
uchar
scsi_inquiry_path(scsi_bus bus, scsi_path_inquiry *inquiry_data)
{
SHOW_FLOW(4, "path_id=%d", bus->path_id);
return bus->interface->path_inquiry(bus->sim_cookie, inquiry_data);
}
static uchar
scsi_reset_bus(scsi_bus_info *bus)
{
return bus->interface->reset_bus(bus->sim_cookie);
}
static status_t
scsi_bus_module_init(void)
{
SHOW_FLOW0(4, "");
return init_temp_sg();
}
static status_t
scsi_bus_module_uninit(void)
{
SHOW_INFO0(4, "");
uninit_temp_sg();
return B_OK;
}
static status_t
std_ops(int32 op, ...)
{
switch (op) {
case B_MODULE_INIT:
return scsi_bus_module_init();
case B_MODULE_UNINIT:
return scsi_bus_module_uninit();
default:
return B_ERROR;
}
}
scsi_bus_interface scsi_bus_module = {
{
{
SCSI_BUS_MODULE_NAME,
0,
std_ops
},
NULL, // supported devices
NULL, // register node
scsi_init_bus,
(void (*)(void *))scsi_uninit_bus,
(status_t (*)(void *))scsi_scan_bus,
(status_t (*)(void *))scsi_scan_bus,
NULL
},
scsi_inquiry_path,
scsi_reset_bus,
};
↑ V547 Expression 'res < ((int) 0)' is always false.