1 /* 2 * Copyright 2004-2010, Haiku, Inc. All Rights Reserved. 3 * Copyright 2002/03, Thomas Kurschel. All rights reserved. 4 * 5 * Distributed under the terms of the MIT License. 6 */ 7 8 9 //! Everything doing the real input/output stuff. 10 11 12 #include "scsi_periph_int.h" 13 #include <scsi.h> 14 15 #include <string.h> 16 #include <stdlib.h> 17 18 19 static status_t 20 inquiry(scsi_periph_device_info *device, scsi_inquiry *inquiry) 21 { 22 const scsi_res_inquiry *device_inquiry = NULL; 23 size_t inquiryLength; 24 25 if (gDeviceManager->get_attr_raw(device->node, SCSI_DEVICE_INQUIRY_ITEM, 26 (const void **)&device_inquiry, &inquiryLength, true) != B_OK) 27 return B_ERROR; 28 29 memcpy(inquiry, device_inquiry, min_c(inquiryLength, sizeof(scsi_inquiry))); 30 return B_OK; 31 } 32 33 34 static status_t 35 prevent_allow(scsi_periph_device_info *device, bool prevent) 36 { 37 scsi_cmd_prevent_allow cmd; 38 39 SHOW_FLOW0(0, ""); 40 41 memset(&cmd, 0, sizeof(cmd)); 42 cmd.opcode = SCSI_OP_PREVENT_ALLOW; 43 cmd.prevent = prevent; 44 45 return periph_simple_exec(device, (uint8 *)&cmd, sizeof(cmd), NULL, 0, 46 SCSI_DIR_NONE); 47 } 48 49 50 /*! Keep this in sync with scsi_raw driver!!! */ 51 static status_t 52 raw_command(scsi_periph_device_info *device, raw_device_command *cmd) 53 { 54 scsi_ccb *request; 55 56 SHOW_FLOW0(0, ""); 57 58 request = device->scsi->alloc_ccb(device->scsi_device); 59 if (request == NULL) 60 return B_NO_MEMORY; 61 62 request->flags = 0; 63 64 if (cmd->flags & B_RAW_DEVICE_DATA_IN) 65 request->flags |= SCSI_DIR_IN; 66 else if (cmd->data_length) 67 request->flags |= SCSI_DIR_OUT; 68 else 69 request->flags |= SCSI_DIR_NONE; 70 71 request->data = (uint8*)cmd->data; 72 request->sg_list = NULL; 73 request->data_length = cmd->data_length; 74 request->sort = -1; 75 request->timeout = cmd->timeout; 76 77 memcpy(request->cdb, cmd->command, SCSI_MAX_CDB_SIZE); 78 request->cdb_length = cmd->command_length; 79 80 device->scsi->sync_io(request); 81 82 // TBD: should we call standard error handler here, or may the 83 // actions done there (like starting the unit) confuse the application? 84 85 cmd->cam_status = request->subsys_status; 86 cmd->scsi_status = request->device_status; 87 88 if ((request->subsys_status & SCSI_AUTOSNS_VALID) != 0 && cmd->sense_data) { 89 memcpy(cmd->sense_data, request->sense, min_c(cmd->sense_data_length, 90 (size_t)SCSI_MAX_SENSE_SIZE - request->sense_resid)); 91 } 92 93 if ((cmd->flags & B_RAW_DEVICE_REPORT_RESIDUAL) != 0) { 94 // this is a bit strange, see Be's sample code where I pinched this from; 95 // normally, residual means "number of unused bytes left" 96 // but here, we have to return "number of used bytes", which is the opposite 97 cmd->data_length = cmd->data_length - request->data_resid; 98 cmd->sense_data_length = SCSI_MAX_SENSE_SIZE - request->sense_resid; 99 } 100 101 device->scsi->free_ccb(request); 102 103 return B_OK; 104 } 105 106 107 /*! Universal read/write function */ 108 static status_t 109 read_write(scsi_periph_device_info *device, scsi_ccb *request, 110 io_operation *operation, uint64 offset, size_t originalNumBlocks, 111 physical_entry* vecs, size_t vecCount, bool isWrite, 112 size_t* _bytesTransferred) 113 { 114 uint32 blockSize = device->block_size; 115 size_t numBlocks = originalNumBlocks; 116 uint32 pos = offset; 117 err_res res; 118 int retries = 0; 119 120 do { 121 size_t numBytes; 122 bool isReadWrite10; 123 124 request->flags = isWrite ? SCSI_DIR_OUT : SCSI_DIR_IN; 125 126 // make sure we avoid 10 byte commands if they aren't supported 127 if (!device->rw10_enabled || device->preferred_ccb_size == 6) { 128 // restricting transfer is OK - the block manager will 129 // take care of transferring the rest 130 if (numBlocks > 0x100) 131 numBlocks = 0x100; 132 133 // no way to break the 21 bit address limit 134 if (pos > 0x200000) 135 return B_BAD_VALUE; 136 137 // don't allow transfer cross the 24 bit address limit 138 // (I'm not sure whether this is allowed, but this way we 139 // are sure to not ask for trouble) 140 if (pos < 0x100000) 141 numBlocks = min_c(numBlocks, 0x100000 - pos); 142 } 143 144 numBytes = numBlocks * blockSize; 145 if (numBlocks != originalNumBlocks) 146 panic("I/O operation would need to be cut."); 147 148 request->data = NULL; 149 request->sg_list = vecs; 150 request->data_length = numBytes; 151 request->sg_count = vecCount; 152 request->io_operation = operation; 153 request->sort = pos; 154 request->timeout = device->std_timeout; 155 // see whether daemon instructed us to post an ordered command; 156 // reset flag after read 157 SHOW_FLOW(3, "flag=%x, next_tag=%x, ordered: %s", 158 (int)request->flags, (int)device->next_tag_action, 159 (request->flags & SCSI_ORDERED_QTAG) != 0 ? "yes" : "no"); 160 161 // use shortest commands whenever possible 162 if (pos + numBlocks < 0x200000 && numBlocks <= 0x100) { 163 scsi_cmd_rw_6 *cmd = (scsi_cmd_rw_6 *)request->cdb; 164 165 isReadWrite10 = false; 166 167 memset(cmd, 0, sizeof(*cmd)); 168 cmd->opcode = isWrite ? SCSI_OP_WRITE_6 : SCSI_OP_READ_6; 169 cmd->high_lba = (pos >> 16) & 0x1f; 170 cmd->mid_lba = (pos >> 8) & 0xff; 171 cmd->low_lba = pos & 0xff; 172 cmd->length = numBlocks; 173 174 request->cdb_length = sizeof(*cmd); 175 } else { 176 scsi_cmd_rw_10 *cmd = (scsi_cmd_rw_10 *)request->cdb; 177 178 isReadWrite10 = true; 179 180 memset(cmd, 0, sizeof(*cmd)); 181 cmd->opcode = isWrite ? SCSI_OP_WRITE_10 : SCSI_OP_READ_10; 182 cmd->relative_address = 0; 183 cmd->force_unit_access = 0; 184 cmd->disable_page_out = 0; 185 cmd->lba = B_HOST_TO_BENDIAN_INT32(pos); 186 cmd->length = B_HOST_TO_BENDIAN_INT16(numBlocks); 187 188 request->cdb_length = sizeof(*cmd); 189 } 190 191 // TODO: last chance to detect errors that occured during concurrent accesses 192 //status_t status = handle->pending_error; 193 //if (status != B_OK) 194 // return status; 195 196 device->scsi->async_io(request); 197 198 acquire_sem(request->completion_sem); 199 200 // ask generic peripheral layer what to do now 201 res = periph_check_error(device, request); 202 203 // TODO: bytes might have been transferred even in the error case! 204 switch (res.action) { 205 case err_act_ok: 206 *_bytesTransferred = numBytes - request->data_resid; 207 break; 208 209 case err_act_start: 210 res = periph_send_start_stop(device, request, 1, 211 device->removable); 212 if (res.action == err_act_ok) 213 res.action = err_act_retry; 214 break; 215 216 case err_act_invalid_req: 217 // if this was a 10 byte command, the device probably doesn't 218 // support them, so disable them and retry 219 if (isReadWrite10) { 220 atomic_and(&device->rw10_enabled, 0); 221 res.action = err_act_retry; 222 } else 223 res.action = err_act_fail; 224 break; 225 } 226 } while ((res.action == err_act_retry && retries++ < 3) 227 || (res.action == err_act_many_retries && retries++ < 30)); 228 229 // peripheral layer only created "read" error, so we have to 230 // map them to "write" errors if this was a write request 231 if (res.error_code == B_DEV_READ_ERROR && isWrite) 232 return B_DEV_WRITE_ERROR; 233 234 return res.error_code; 235 } 236 237 238 // #pragma mark - public functions 239 240 241 status_t 242 periph_ioctl(scsi_periph_handle_info *handle, int op, void *buffer, 243 size_t length) 244 { 245 switch (op) { 246 case B_GET_MEDIA_STATUS: { 247 status_t res = B_OK; 248 249 if (handle->device->removable) 250 res = periph_get_media_status(handle); 251 252 SHOW_FLOW(2, "%s", strerror(res)); 253 254 *(status_t *)buffer = res; 255 return B_OK; 256 } 257 258 case B_SCSI_INQUIRY: 259 return inquiry(handle->device, (scsi_inquiry *)buffer); 260 261 case B_SCSI_PREVENT_ALLOW: 262 return prevent_allow(handle->device, *(bool *)buffer); 263 264 case B_RAW_DEVICE_COMMAND: 265 return raw_command(handle->device, (raw_device_command*)buffer); 266 267 default: 268 if (handle->device->scsi->ioctl != NULL) { 269 return handle->device->scsi->ioctl(handle->device->scsi_device, 270 op, buffer, length); 271 } 272 273 SHOW_ERROR(4, "Unknown ioctl: %x", op); 274 return B_BAD_VALUE; 275 } 276 } 277 278 279 /*! Kernel daemon - once in a minute, it sets a flag so that the next command 280 is executed ordered; this way, we avoid starvation of SCSI commands inside 281 the SCSI queuing system - the ordered command waits for all previous 282 commands and thus no command can starve longer then a minute 283 */ 284 void 285 periph_sync_queue_daemon(void *arg, int iteration) 286 { 287 scsi_periph_device_info *device = (scsi_periph_device_info *)arg; 288 289 SHOW_FLOW0(3, "Setting ordered flag for next R/W access"); 290 atomic_or(&device->next_tag_action, SCSI_ORDERED_QTAG); 291 } 292 293 294 status_t 295 periph_read_write(scsi_periph_device_info *device, scsi_ccb *request, 296 uint64 offset, size_t numBlocks, physical_entry* vecs, size_t vecCount, 297 bool isWrite, size_t* _bytesTransferred) 298 { 299 return read_write(device, request, NULL, offset, numBlocks, vecs, vecCount, 300 isWrite, _bytesTransferred); 301 } 302 303 304 status_t 305 periph_io(scsi_periph_device_info *device, io_operation *operation, 306 size_t* _bytesTransferred) 307 { 308 const uint32 blockSize = device->block_size; 309 310 // don't test rw10_enabled restrictions - this flag may get changed 311 scsi_ccb *request = device->scsi->alloc_ccb(device->scsi_device); 312 if (request == NULL) 313 return B_NO_MEMORY; 314 315 status_t status = read_write(device, request, operation, 316 operation->Offset() / blockSize, operation->Length() / blockSize, 317 (physical_entry *)operation->Vecs(), operation->VecCount(), 318 operation->IsWrite(), _bytesTransferred); 319 320 device->scsi->free_ccb(request); 321 return status; 322 } 323 324