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If applicable, add the following below this CDDL HEADER, with the fields enclosed by brackets "[]" replaced with your own identifying information: Portions Copyright [yyyy] [name of copyright owner] 6 .TH SCSI_INIT_PKT 9F "Jan 16, 2006" 7 .SH NAME 8 scsi_init_pkt \- prepare a complete SCSI packet 9 .SH SYNOPSIS 10 .LP 11 .nf 12 #include <sys/scsi/scsi.h> 13 14 15 16 \fBstruct scsi_pkt *\fR\fBscsi_init_pkt\fR(\fBstruct scsi_address *\fR\fIap\fR, 17 \fBstruct scsi_pkt *\fR\fIpktp\fR, \fBstruct buf *\fR\fIbp\fR, \fBint\fR \fIcmdlen\fR, \fBint\fR \fIstatuslen\fR, 18 \fBint\fR \fIprivatelen\fR, \fBint\fR \fIflags\fR, \fBint\fR \fB(*\fRcallback\fB)(caddr_t)\fR, \fBcaddr_t\fR \fIarg\fR); 19 .fi 20 21 .SH INTERFACE LEVEL 22 .sp 23 .LP 24 Solaris DDI specific (Solaris DDI). 25 .SH PARAMETERS 26 .sp 27 .ne 2 28 .na 29 \fB\fIap\fR\fR 30 .ad 31 .sp .6 32 .RS 4n 33 Pointer to a \fBscsi_address\fR(9S) structure. 34 .RE 35 36 .sp 37 .ne 2 38 .na 39 \fB\fIpktp\fR\fR 40 .ad 41 .sp .6 42 .RS 4n 43 A pointer to a \fBscsi_pkt\fR(9S) structure. 44 .RE 45 46 .sp 47 .ne 2 48 .na 49 \fB\fIbp\fR\fR 50 .ad 51 .sp .6 52 .RS 4n 53 Pointer to a \fBbuf\fR(9S) structure. 54 .RE 55 56 .sp 57 .ne 2 58 .na 59 \fB\fIcmdlen\fR\fR 60 .ad 61 .sp .6 62 .RS 4n 63 The required length for the \fBSCSI \fRcommand descriptor block (\fBCDB\fR) in 64 bytes. 65 .RE 66 67 .sp 68 .ne 2 69 .na 70 \fB\fIstatuslen\fR\fR 71 .ad 72 .sp .6 73 .RS 4n 74 The required length for the \fBSCSI \fRstatus completion block (\fBSCB\fR) in 75 bytes. Valid values are: 76 .sp 77 .ne 2 78 .na 79 \fB\fB0\fR\fR 80 .ad 81 .sp .6 82 .RS 4n 83 No status back. 84 .RE 85 86 .sp 87 .ne 2 88 .na 89 \fB\fB1\fR\fR 90 .ad 91 .sp .6 92 .RS 4n 93 Return SCSI status byte. 94 .RE 95 96 .sp 97 .ne 2 98 .na 99 \fB\fBsizeof(scsi_arq_status)\fR\fR 100 .ad 101 .sp .6 102 .RS 4n 103 Return status information in a \fBscsi_arq_status\fR structure. This will 104 include up to 20 bytes of sense data. Please refer to \fBscsi_arq_status\fR(9S) 105 for more information. 106 .sp 107 For extra sense packets (\fBPKT_XARQ\fR flag asserted), set \fIstatuslen\fR to 108 be a greater number like, (\fIN\fR + \fBsizeof(struct scsi_arq_status)\fR) 109 where \fIN\fR is the number of extra bytes beyond the default 20. For example, 110 \fIN\fR=1 requests 21 bytes of sense, \fIN\fR=235 asks for 255 bytes. 111 .RE 112 113 .RE 114 115 .sp 116 .ne 2 117 .na 118 \fB\fIprivatelen\fR\fR 119 .ad 120 .sp .6 121 .RS 4n 122 The required length for the \fIpkt_private\fR area. 123 .RE 124 125 .sp 126 .ne 2 127 .na 128 \fB\fIflags\fR\fR 129 .ad 130 .sp .6 131 .RS 4n 132 Flags modifier. 133 .RE 134 135 .sp 136 .ne 2 137 .na 138 \fB\fIcallback\fR\fR 139 .ad 140 .sp .6 141 .RS 4n 142 A pointer to a callback function, \fBNULL_FUNC\fR, or \fBSLEEP_FUNC\fR. 143 .RE 144 145 .sp 146 .ne 2 147 .na 148 \fB\fIarg\fR\fR 149 .ad 150 .sp .6 151 .RS 4n 152 The \fIcallback\fR function argument. 153 .RE 154 155 .SH DESCRIPTION 156 .sp 157 .LP 158 Target drivers use \fBscsi_init_pkt()\fR to request the transport layer to 159 allocate and initialize a packet for a \fBSCSI\fR command which possibly 160 includes a data transfer. If \fIpktp\fR is \fINULL,\fR a new \fBscsi_pkt\fR(9S) 161 is allocated using the \fBHBA\fR driver's packet allocator. The \fIbp\fR is a 162 pointer to a \fBbuf\fR(9S) structure. If \fIbp\fR is non-\fINULL\fR and 163 contains a valid byte count, the \fBbuf\fR(9S) structure is also set up for 164 \fBDMA \fRtransfer using the \fBHBA\fR driver \fBDMA\fR resources allocator. 165 When \fIbp\fR is allocated by \fBscsi_alloc_consistent_buf\fR(9F), the 166 \fBPKT_CONSISTENT\fR bit must be set in the \fIflags\fR argument to ensure 167 proper operation. If \fIprivatelen\fR is non-zero then additional space is 168 allocated for the \fIpkt_private\fR area of the \fBscsi_pkt\fR(9S). On return 169 \fIpkt_private\fR points to this additional space. Otherwise \fIpkt_private\fR 170 is a pointer that is typically used to store the \fIbp\fR during execution of 171 the command. In this case \fIpkt_private\fR is \fINULL\fR on return. 172 .sp 173 .LP 174 The \fIflags\fR argument is a set of bit flags. Possible bits include: 175 .sp 176 .ne 2 177 .na 178 \fB\fBPKT_CONSISTENT\fR\fR 179 .ad 180 .sp .6 181 .RS 4n 182 This must be set if the \fBDMA\fR buffer was allocated using 183 \fBscsi_alloc_consistent_buf\fR(9F). In this case, the \fBHBA\fR driver will 184 guarantee that the data transfer is properly synchronized before performing the 185 target driver's command completion callback. 186 .RE 187 188 .sp 189 .ne 2 190 .na 191 \fB\fBPKT_DMA_PARTIAL\fR\fR 192 .ad 193 .sp .6 194 .RS 4n 195 This may be set if the driver can accept a partial \fBDMA\fR mapping. If set, 196 \fBscsi_init_pkt()\fR will allocate \fBDMA\fR resources with the 197 \fBDDI_DMA_PARTIAL\fR bit set in the \fBdmar_flag\fR element of the 198 \fBddi_dma_req\fR(9S) structure. The \fBpkt_resid\fR field of the 199 \fBscsi_pkt\fR(9S) structure may be returned with a non-zero value, which 200 indicates the number of bytes for which \fBscsi_init_pkt()\fR was unable to 201 allocate DMA resources. In this case, a subsequent call to 202 \fBscsi_init_pkt()\fR may be made for the same \fIpktp\fR and \fIbp\fR to 203 adjust the DMA resources to the next portion of the transfer. This sequence 204 should be repeated until the \fBpkt_resid\fR field is returned with a zero 205 value, which indicates that with transport of this final portion the entire 206 original request will have been satisfied. 207 .RE 208 209 .sp 210 .ne 2 211 .na 212 \fB\fBPKT_XARQ\fR\fR 213 .ad 214 .sp .6 215 .RS 4n 216 Setting this flag requests that the \fBHBA\fR return extra sense data for this 217 \fBscsi_pkt\fR(9S). The default auto request sense mechanism returns up to 20 218 bytes. More than 20 bytes of sense data can be requested by setting this flag 219 and setting the \fIstatuslen\fR correctly. Set the \fIstatuslen\fR to be the 220 \fBsizeof(struct scsi_arq_status)\fR plus the number of sense bytes needed 221 beyond 20. For example, set statuslen to be \fB(sizeof(struct scsi_arq_status) 222 + 5)\fR for 25 bytes of sense. 223 .RE 224 225 .sp 226 .LP 227 When calling \fBscsi_init_pkt()\fR to move already-allocated \fBDMA\fR 228 resources, the \fIcmdlen\fR, \fIstatuslen\fR, and \fIprivatelen\fR fields are 229 ignored. 230 .sp 231 .LP 232 The last argument \fIarg\fR is supplied to the \fIcallback\fR function when it 233 is invoked. 234 .sp 235 .LP 236 \fIcallback\fR indicates what the allocator routines should do when resources 237 are not available: 238 .sp 239 .ne 2 240 .na 241 \fB\fBNULL_FUNC\fR\fR 242 .ad 243 .RS 16n 244 Do not wait for resources. Return a \fINULL\fR pointer. 245 .RE 246 247 .sp 248 .ne 2 249 .na 250 \fB\fBSLEEP_FUNC\fR\fR 251 .ad 252 .RS 16n 253 Wait indefinitely for resources. 254 .RE 255 256 .sp 257 .ne 2 258 .na 259 \fBOther Values\fR 260 .ad 261 .RS 16n 262 \fIcallback\fR points to a function which is called when resources may have 263 become available. \fIcallback\fR must return either \fB0\fR (indicating that it 264 attempted to allocate resources but again failed to do so), in which case it is 265 put back on a list to be called again later, or \fB1\fR indicating either 266 success in allocating resources or indicating that it no longer cares for a 267 retry. 268 .RE 269 270 .sp 271 .LP 272 When allocating \fBDMA\fR resources, \fBscsi_init_pkt()\fR returns the 273 \fBscsi_pkt\fR field \fBpkt_resid\fR as the number of residual bytes for which 274 the system was unable to allocate \fBDMA\fR resources. A \fBpkt_resid\fR of 275 \fB0\fR means that all necessary \fBDMA\fR resources were allocated. 276 .SH RETURN VALUES 277 .sp 278 .LP 279 The \fBscsi_init_pkt()\fR function returns \fINULL\fR if the packet or 280 \fBDMA\fR resources could not be allocated. Otherwise, it returns a pointer to 281 an initialized \fBscsi_pkt\fR(9S). If \fIpktp\fR was not \fINULL\fR the return 282 value will be \fIpktp\fR on successful initialization of the packet. 283 .SH CONTEXT 284 .sp 285 .LP 286 If \fIcallback\fR is \fBSLEEP_FUNC\fR, then this routine can be called only 287 from user-level code. Otherwise, it can be called from user, interrupt, or 288 kernel context. The \fIcallback\fR function may not block or call routines that 289 block. 290 .SH EXAMPLES 291 .LP 292 \fBExample 1 \fRAllocating a Packet Without \fBDMA\fR Resources Attached 293 .sp 294 .LP 295 To allocate a packet without \fBDMA\fR resources attached, use: 296 297 .sp 298 .in +2 299 .nf 300 pkt = scsi_init_pkt(&devp->sd_address, NULL, NULL, CDB_GROUP1, 301 1, sizeof (struct my_pkt_private *), 0, 302 sd_runout, sd_unit); 303 .fi 304 .in -2 305 306 .LP 307 \fBExample 2 \fRAllocating a Packet With \fBDMA\fR Resources Attached 308 .sp 309 .LP 310 To allocate a packet with \fBDMA\fR resources attached use: 311 312 .sp 313 .in +2 314 .nf 315 pkt = scsi_init_pkt(&devp->sd_address, NULL, bp, CDB_GROUP1, 316 sizeof(struct scsi_arq_status), 0, 0, NULL_FUNC, NULL); 317 .fi 318 .in -2 319 320 .LP 321 \fBExample 3 \fRAttaching \fBDMA\fR Resources to a Preallocated Packet 322 .sp 323 .LP 324 To attach \fBDMA\fR resources to a preallocated packet, use: 325 326 .sp 327 .in +2 328 .nf 329 pkt = scsi_init_pkt(&devp->sd_address, old_pkt, bp, 0, 330 0, 0, 0, sd_runout, (caddr_t) sd_unit); 331 .fi 332 .in -2 333 334 .LP 335 \fBExample 4 \fRAllocating a Packet with Consistent \fBDMA\fR Resources 336 Attached 337 .sp 338 .LP 339 Since the packet is already allocated, the \fIcmdlen\fR, \fIstatuslen\fR and 340 \fIprivatelen\fR are \fB0\fR. To allocate a packet with consistent \fBDMA\fR 341 resources attached, use: 342 343 .sp 344 .in +2 345 .nf 346 bp = scsi_alloc_consistent_buf(&devp->sd_address, NULL, 347 SENSE_LENGTH, B_READ, SLEEP_FUNC, NULL); 348 pkt = scsi_init_pkt(&devp->sd_address, NULL, bp, CDB_GROUP0, 349 sizeof(struct scsi_arq_status), sizeof (struct my_pkt_private *), 350 PKT_CONSISTENT, SLEEP_FUNC, NULL); 351 .fi 352 .in -2 353 354 .LP 355 \fBExample 5 \fRAllocating a Packet with Partial \fBDMA\fR Resources Attached 356 .sp 357 .LP 358 To allocate a packet with partial \fBDMA\fR resources attached, use: 359 360 .sp 361 .in +2 362 .nf 363 my_pkt = scsi_init_pkt(&devp->sd_address, NULL, bp, CDB_GROUP0, 364 1, sizeof (struct buf *), PKT_DMA_PARTIAL, 365 SLEEP_FUNC, NULL); 366 .fi 367 .in -2 368 369 .SH SEE ALSO 370 .sp 371 .LP 372 \fBscsi_alloc_consistent_buf\fR(9F), \fBscsi_destroy_pkt\fR(9F), 373 \fBscsi_dmaget\fR(9F), \fBscsi_pktalloc\fR(9F), \fBbuf\fR(9S), 374 \fBddi_dma_req\fR(9S), \fBscsi_address\fR(9S), \fBscsi_pkt\fR(9S) 375 .sp 376 .LP 377 \fIWriting Device Drivers\fR 378 .SH NOTES 379 .sp 380 .LP 381 If a \fBDMA\fR allocation request fails with \fBDDI_DMA_NOMAPPING\fR, the 382 \fBB_ERROR\fR flag will be set in \fIbp\fR, and the \fBb_error\fR field will be 383 set to \fBEFAULT\fR. 384 .sp 385 .LP 386 If a \fBDMA\fR allocation request fails with \fBDDI_DMA_TOOBIG\fR, the 387 \fBB_ERROR\fR flag will be set in \fIbp\fR, and the \fBb_error\fR field will be 388 set to \fBEINVAL\fR.