xref: /haiku/src/add-ons/kernel/bus_managers/scsi/busses.cpp (revision a3e794ae459fec76826407f8ba8c94cd3535f128)
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 	res = INIT_BEN(&bus->mutex, "scsi_bus_mutex");
136 	if (res < B_OK)
137 		goto err3;
138 
139 	spinlock_irq_init(&bus->dpc_lock);
140 
141 	res = scsi_init_ccb_alloc(bus);
142 	if (res < B_OK)
143 		goto err2;
144 
145 	bus->service_thread = spawn_kernel_thread(scsi_service_threadproc,
146 		"scsi_bus_service", BUS_SERVICE_PRIORITY, bus);
147 
148 	if (bus->service_thread < 0) {
149 		res = bus->service_thread;
150 		goto err1;
151 	}
152 
153 	resume_thread(bus->service_thread);
154 
155 	return bus;
156 
157 err1:
158 	scsi_uninit_ccb_alloc(bus);
159 err2:
160 	DELETE_BEN(&bus->mutex);
161 err3:
162 	delete_sem(bus->start_service);
163 err4:
164 	delete_sem(bus->scan_lun_lock);
165 err6:
166 	free(bus);
167 	return NULL;
168 }
169 
170 
171 static status_t
172 scsi_destroy_bus(scsi_bus_info *bus)
173 {
174 	int32 retcode;
175 
176 	// noone is using this bus now, time to clean it up
177 	bus->shutting_down = true;
178 	release_sem(bus->start_service);
179 
180 	wait_for_thread(bus->service_thread, &retcode);
181 
182 	delete_sem(bus->start_service);
183 	DELETE_BEN(&bus->mutex);
184 	delete_sem(bus->scan_lun_lock);
185 
186 	scsi_uninit_ccb_alloc(bus);
187 
188 	return B_OK;
189 }
190 
191 
192 static status_t
193 scsi_init_bus(device_node *node, void **cookie)
194 {
195 	uint8 path_id;
196 	scsi_bus_info *bus;
197 	status_t res;
198 
199 	SHOW_FLOW0( 3, "" );
200 
201 	if (pnp->get_attr_uint8(node, SCSI_BUS_PATH_ID_ITEM, &path_id, false) != B_OK)
202 		return B_ERROR;
203 
204 	bus = scsi_create_bus(node, path_id);
205 	if (bus == NULL)
206 		return B_NO_MEMORY;
207 
208 	// extract controller/protocoll restrictions from node
209 	if (pnp->get_attr_uint32(node, B_DMA_ALIGNMENT, &bus->dma_params.alignment,
210 			true) != B_OK)
211 		bus->dma_params.alignment = 0;
212 	if (pnp->get_attr_uint32(node, B_DMA_MAX_TRANSFER_BLOCKS,
213 			&bus->dma_params.max_blocks, true) != B_OK)
214 		bus->dma_params.max_blocks = 0xffffffff;
215 	if (pnp->get_attr_uint32(node, B_DMA_BOUNDARY,
216 			&bus->dma_params.dma_boundary, true) != B_OK)
217 		bus->dma_params.dma_boundary = ~0;
218 	if (pnp->get_attr_uint32(node, B_DMA_MAX_SEGMENT_BLOCKS,
219 			&bus->dma_params.max_sg_block_size, true) != B_OK)
220 		bus->dma_params.max_sg_block_size = 0xffffffff;
221 	if (pnp->get_attr_uint32(node, B_DMA_MAX_SEGMENT_COUNT,
222 			&bus->dma_params.max_sg_blocks, true) != B_OK)
223 		bus->dma_params.max_sg_blocks = ~0;
224 
225 	// do some sanity check:
226 	bus->dma_params.max_sg_block_size &= ~bus->dma_params.alignment;
227 
228 	if (bus->dma_params.alignment > B_PAGE_SIZE) {
229 		SHOW_ERROR(0, "Alignment (0x%" B_PRIx32 ") must be less then "
230 			"B_PAGE_SIZE", bus->dma_params.alignment);
231 		res = B_ERROR;
232 		goto err;
233 	}
234 
235 	if (bus->dma_params.max_sg_block_size < 1) {
236 		SHOW_ERROR(0, "Max s/g block size (0x%" B_PRIx32 ") is too small",
237 			bus->dma_params.max_sg_block_size);
238 		res = B_ERROR;
239 		goto err;
240 	}
241 
242 	if (bus->dma_params.dma_boundary < B_PAGE_SIZE - 1) {
243 		SHOW_ERROR(0, "DMA boundary (0x%" B_PRIx32 ") must be at least "
244 			"B_PAGE_SIZE", bus->dma_params.dma_boundary);
245 		res = B_ERROR;
246 		goto err;
247 	}
248 
249 	if (bus->dma_params.max_blocks < 1 || bus->dma_params.max_sg_blocks < 1) {
250 		SHOW_ERROR(0, "Max blocks (%" B_PRIu32 ") and max s/g blocks (%"
251 			B_PRIu32 ") must be at least 1", bus->dma_params.max_blocks,
252 			bus->dma_params.max_sg_blocks);
253 		res = B_ERROR;
254 		goto err;
255 	}
256 
257 	{
258 		device_node *parent = pnp->get_parent_node(node);
259 		pnp->get_driver(parent, (driver_module_info **)&bus->interface,
260 			(void **)&bus->sim_cookie);
261 		pnp->put_node(parent);
262 
263 		bus->interface->set_scsi_bus(bus->sim_cookie, bus);
264 	}
265 
266 	// cache inquiry data
267 	scsi_inquiry_path(bus, &bus->inquiry_data);
268 
269 	// get max. number of commands on bus
270 	bus->left_slots = bus->inquiry_data.hba_queue_size;
271 	SHOW_FLOW( 3, "Bus has %d slots", bus->left_slots );
272 
273 	*cookie = bus;
274 
275 	return B_OK;
276 
277 err:
278 	scsi_destroy_bus(bus);
279 	return res;
280 }
281 
282 
283 static void
284 scsi_uninit_bus(scsi_bus_info *bus)
285 {
286 	scsi_destroy_bus(bus);
287 }
288 
289 
290 uchar
291 scsi_inquiry_path(scsi_bus bus, scsi_path_inquiry *inquiry_data)
292 {
293 	SHOW_FLOW(4, "path_id=%d", bus->path_id);
294 	return bus->interface->path_inquiry(bus->sim_cookie, inquiry_data);
295 }
296 
297 
298 static uchar
299 scsi_reset_bus(scsi_bus_info *bus)
300 {
301 	return bus->interface->reset_bus(bus->sim_cookie);
302 }
303 
304 
305 static status_t
306 scsi_bus_module_init(void)
307 {
308 	SHOW_FLOW0(4, "");
309 	return init_temp_sg();
310 }
311 
312 
313 static status_t
314 scsi_bus_module_uninit(void)
315 {
316 	SHOW_INFO0(4, "");
317 
318 	uninit_temp_sg();
319 	return B_OK;
320 }
321 
322 
323 static status_t
324 std_ops(int32 op, ...)
325 {
326 	switch (op) {
327 		case B_MODULE_INIT:
328 			return scsi_bus_module_init();
329 		case B_MODULE_UNINIT:
330 			return scsi_bus_module_uninit();
331 
332 		default:
333 			return B_ERROR;
334 	}
335 }
336 
337 
338 scsi_bus_interface scsi_bus_module = {
339 	{
340 		{
341 			SCSI_BUS_MODULE_NAME,
342 			0,
343 			std_ops
344 		},
345 
346 		NULL,	// supported devices
347 		NULL,	// register node
348 		scsi_init_bus,
349 		(void (*)(void *))scsi_uninit_bus,
350 		(status_t (*)(void *))scsi_scan_bus,
351 		(status_t (*)(void *))scsi_scan_bus,
352 		NULL
353 	},
354 
355 	scsi_inquiry_path,
356 	scsi_reset_bus,
357 };
358