xref: /haiku/src/add-ons/kernel/bus_managers/scsi/busses.cpp (revision 344ded80d400028c8f561b4b876257b94c12db4a)
1 /*
2  * Copyright 2002/03, Thomas Kurschel. All rights reserved.
3  * Distributed under the terms of the MIT License.
4  */
5 
6 /*
7 	Part of Open SCSI bus manager
8 
9 	Bus node layer.
10 
11 	Whenever a controller driver publishes a new controller, a new SCSI bus
12 	for public and internal use is registered in turn. After that, this
13 	bus is told to rescan for devices. For each device, there is a
14 	device registered for peripheral drivers. (see devices.c)
15 */
16 
17 #include "scsi_internal.h"
18 
19 #include <string.h>
20 #include <malloc.h>
21 
22 
23 // bus service should hurry up a bit - good controllers don't take much time
24 // but are very happy to be busy; don't make it realtime though as we
25 // don't really need that but would risk to steel processing power of
26 // realtime-demanding threads
27 #define BUS_SERVICE_PRIORITY B_URGENT_DISPLAY_PRIORITY
28 
29 
30 /**	implementation of service thread:
31  *	it handles DPC and pending requests
32  */
33 
34 static void
35 scsi_do_service(scsi_bus_info *bus)
36 {
37 	while (true) {
38 		SHOW_FLOW0( 3, "" );
39 
40 		// handle DPCs first as they are more urgent
41 		if (scsi_check_exec_dpc(bus))
42 			continue;
43 
44 		if (scsi_check_exec_service(bus))
45 			continue;
46 
47 		break;
48 	}
49 }
50 
51 
52 /** main loop of service thread */
53 
54 static int32
55 scsi_service_threadproc(void *arg)
56 {
57 	scsi_bus_info *bus = (scsi_bus_info *)arg;
58 	int32 processed_notifications = 0;
59 
60 	SHOW_FLOW(3, "bus = %p", bus);
61 
62 	while (true) {
63 		// we handle multiple requests in scsi_do_service at once;
64 		// to save time, we will acquire all notifications that are sent
65 		// up to now at once.
66 		// (Sadly, there is no "set semaphore to zero" function, so this
67 		//  is a poor-man emulation)
68 		acquire_sem_etc(bus->start_service, processed_notifications + 1, 0, 0);
69 
70 		SHOW_FLOW0( 3, "1" );
71 
72 		if (bus->shutting_down)
73 			break;
74 
75 		// get number of notifications _before_ servicing to make sure no new
76 		// notifications are sent after do_service()
77 		get_sem_count(bus->start_service, &processed_notifications);
78 
79 		scsi_do_service(bus);
80 	}
81 
82 	return 0;
83 }
84 
85 
86 static scsi_bus_info *
87 scsi_create_bus(device_node *node, uint8 path_id)
88 {
89 	scsi_bus_info *bus;
90 	int res;
91 
92 	SHOW_FLOW0(3, "");
93 
94 	bus = (scsi_bus_info *)malloc(sizeof(*bus));
95 	if (bus == NULL)
96 		return NULL;
97 
98 	memset(bus, 0, sizeof(*bus));
99 
100 	bus->path_id = path_id;
101 
102 	if (pnp->get_attr_uint32(node, SCSI_DEVICE_MAX_TARGET_COUNT, &bus->max_target_count, true) != B_OK)
103 		bus->max_target_count = MAX_TARGET_ID + 1;
104 	if (pnp->get_attr_uint32(node, SCSI_DEVICE_MAX_LUN_COUNT, &bus->max_lun_count, true) != B_OK)
105 		bus->max_lun_count = MAX_LUN_ID + 1;
106 
107 	// our scsi_ccb only has a uchar for target_id
108 	if (bus->max_target_count > 256)
109 		bus->max_target_count = 256;
110 	// our scsi_ccb only has a uchar for target_lun
111 	if (bus->max_lun_count > 256)
112 		bus->max_lun_count = 256;
113 
114 	bus->node = node;
115 	bus->lock_count = bus->blocked[0] = bus->blocked[1] = 0;
116 	bus->sim_overflow = 0;
117 	bus->shutting_down = false;
118 
119 	bus->waiting_devices = NULL;
120 	//bus->resubmitted_req = NULL;
121 
122 	bus->dpc_list = NULL;
123 
124 	if ((bus->scan_lun_lock = create_sem(1, "scsi_scan_lun_lock")) < 0) {
125 		res = bus->scan_lun_lock;
126 		goto err6;
127 	}
128 
129 	bus->start_service = create_sem(0, "scsi_start_service");
130 	if (bus->start_service < 0) {
131 		res = bus->start_service;
132 		goto err4;
133 	}
134 
135 	mutex_init(&bus->mutex, "scsi_bus_mutex");
136 	spinlock_irq_init(&bus->dpc_lock);
137 
138 	bus->service_thread = spawn_kernel_thread(scsi_service_threadproc,
139 		"scsi_bus_service", BUS_SERVICE_PRIORITY, bus);
140 
141 	if (bus->service_thread < 0) {
142 		res = bus->service_thread;
143 		goto err1;
144 	}
145 
146 	resume_thread(bus->service_thread);
147 
148 	return bus;
149 
150 err1:
151 	mutex_destroy(&bus->mutex);
152 	delete_sem(bus->start_service);
153 err4:
154 	delete_sem(bus->scan_lun_lock);
155 err6:
156 	free(bus);
157 	return NULL;
158 }
159 
160 
161 static status_t
162 scsi_destroy_bus(scsi_bus_info *bus)
163 {
164 	// noone is using this bus now, time to clean it up
165 	bus->shutting_down = true;
166 	release_sem(bus->start_service);
167 
168 	status_t retcode;
169 	wait_for_thread(bus->service_thread, &retcode);
170 
171 	delete_sem(bus->start_service);
172 	mutex_destroy(&bus->mutex);
173 	delete_sem(bus->scan_lun_lock);
174 
175 	return B_OK;
176 }
177 
178 
179 static status_t
180 scsi_init_bus(device_node *node, void **cookie)
181 {
182 	uint8 path_id;
183 	scsi_bus_info *bus;
184 	status_t res;
185 
186 	SHOW_FLOW0( 3, "" );
187 
188 	if (pnp->get_attr_uint8(node, SCSI_BUS_PATH_ID_ITEM, &path_id, false) != B_OK)
189 		return B_ERROR;
190 
191 	bus = scsi_create_bus(node, path_id);
192 	if (bus == NULL)
193 		return B_NO_MEMORY;
194 
195 	// extract controller/protocoll restrictions from node
196 	if (pnp->get_attr_uint32(node, B_DMA_ALIGNMENT, &bus->dma_params.alignment,
197 			true) != B_OK)
198 		bus->dma_params.alignment = 0;
199 	if (pnp->get_attr_uint32(node, B_DMA_MAX_TRANSFER_BLOCKS,
200 			&bus->dma_params.max_blocks, true) != B_OK)
201 		bus->dma_params.max_blocks = 0xffffffff;
202 	if (pnp->get_attr_uint32(node, B_DMA_BOUNDARY,
203 			&bus->dma_params.dma_boundary, true) != B_OK)
204 		bus->dma_params.dma_boundary = ~0;
205 	if (pnp->get_attr_uint32(node, B_DMA_MAX_SEGMENT_BLOCKS,
206 			&bus->dma_params.max_sg_block_size, true) != B_OK)
207 		bus->dma_params.max_sg_block_size = 0xffffffff;
208 	if (pnp->get_attr_uint32(node, B_DMA_MAX_SEGMENT_COUNT,
209 			&bus->dma_params.max_sg_blocks, true) != B_OK)
210 		bus->dma_params.max_sg_blocks = ~0;
211 	if (pnp->get_attr_uint64(node, B_DMA_HIGH_ADDRESS,
212 			&bus->dma_params.high_address, true) != B_OK)
213 		bus->dma_params.high_address = ~0;
214 
215 	// do some sanity check:
216 	bus->dma_params.max_sg_block_size &= ~bus->dma_params.alignment;
217 
218 	if (bus->dma_params.alignment > B_PAGE_SIZE) {
219 		SHOW_ERROR(0, "Alignment (0x%" B_PRIx32 ") must be less then "
220 			"B_PAGE_SIZE", bus->dma_params.alignment);
221 		res = B_ERROR;
222 		goto err;
223 	}
224 
225 	if (bus->dma_params.max_sg_block_size < 1) {
226 		SHOW_ERROR(0, "Max s/g block size (0x%" B_PRIx32 ") is too small",
227 			bus->dma_params.max_sg_block_size);
228 		res = B_ERROR;
229 		goto err;
230 	}
231 
232 	if (bus->dma_params.dma_boundary < B_PAGE_SIZE - 1) {
233 		SHOW_ERROR(0, "DMA boundary (0x%" B_PRIx32 ") must be at least "
234 			"B_PAGE_SIZE", bus->dma_params.dma_boundary);
235 		res = B_ERROR;
236 		goto err;
237 	}
238 
239 	if (bus->dma_params.max_blocks < 1 || bus->dma_params.max_sg_blocks < 1) {
240 		SHOW_ERROR(0, "Max blocks (%" B_PRIu32 ") and max s/g blocks (%"
241 			B_PRIu32 ") must be at least 1", bus->dma_params.max_blocks,
242 			bus->dma_params.max_sg_blocks);
243 		res = B_ERROR;
244 		goto err;
245 	}
246 
247 	{
248 		device_node *parent = pnp->get_parent_node(node);
249 		pnp->get_driver(parent, (driver_module_info **)&bus->interface,
250 			(void **)&bus->sim_cookie);
251 		pnp->put_node(parent);
252 
253 		bus->interface->set_scsi_bus(bus->sim_cookie, bus);
254 	}
255 
256 	// cache inquiry data
257 	scsi_inquiry_path(bus, &bus->inquiry_data);
258 
259 	// get max. number of commands on bus
260 	bus->left_slots = bus->inquiry_data.hba_queue_size;
261 	SHOW_FLOW( 3, "Bus has %d slots", bus->left_slots );
262 
263 	*cookie = bus;
264 
265 	return B_OK;
266 
267 err:
268 	scsi_destroy_bus(bus);
269 	return res;
270 }
271 
272 
273 static void
274 scsi_uninit_bus(scsi_bus_info *bus)
275 {
276 	scsi_destroy_bus(bus);
277 }
278 
279 
280 uchar
281 scsi_inquiry_path(scsi_bus bus, scsi_path_inquiry *inquiry_data)
282 {
283 	SHOW_FLOW(4, "path_id=%d", bus->path_id);
284 	return bus->interface->path_inquiry(bus->sim_cookie, inquiry_data);
285 }
286 
287 
288 static uchar
289 scsi_reset_bus(scsi_bus_info *bus)
290 {
291 	return bus->interface->reset_bus(bus->sim_cookie);
292 }
293 
294 
295 static status_t
296 scsi_bus_module_init(void)
297 {
298 	SHOW_FLOW0(4, "");
299 
300 	status_t status = init_ccb_alloc();
301 	if (status != B_OK)
302 		return status;
303 	return init_temp_sg();
304 }
305 
306 
307 static status_t
308 scsi_bus_module_uninit(void)
309 {
310 	SHOW_INFO0(4, "");
311 
312 	uninit_ccb_alloc();
313 	uninit_temp_sg();
314 	return B_OK;
315 }
316 
317 
318 static status_t
319 std_ops(int32 op, ...)
320 {
321 	switch (op) {
322 		case B_MODULE_INIT:
323 			return scsi_bus_module_init();
324 		case B_MODULE_UNINIT:
325 			return scsi_bus_module_uninit();
326 
327 		default:
328 			return B_ERROR;
329 	}
330 }
331 
332 
333 scsi_bus_interface scsi_bus_module = {
334 	{
335 		{
336 			SCSI_BUS_MODULE_NAME,
337 			0,
338 			std_ops
339 		},
340 
341 		NULL,	// supported devices
342 		NULL,	// register node
343 		scsi_init_bus,
344 		(void (*)(void *))scsi_uninit_bus,
345 		(status_t (*)(void *))scsi_scan_bus,
346 		(status_t (*)(void *))scsi_scan_bus,
347 		NULL
348 	},
349 
350 	scsi_inquiry_path,
351 	scsi_reset_bus,
352 };
353