1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _SCSI_SCSI_CMND_H 3 #define _SCSI_SCSI_CMND_H 4 5 #include <linux/dma-mapping.h> 6 #include <linux/blkdev.h> 7 #include <linux/t10-pi.h> 8 #include <linux/list.h> 9 #include <linux/types.h> 10 #include <linux/timer.h> 11 #include <linux/scatterlist.h> 12 #include <scsi/scsi_device.h> 13 #include <scsi/scsi_request.h> 14 15 struct Scsi_Host; 16 17 /* 18 * MAX_COMMAND_SIZE is: 19 * The longest fixed-length SCSI CDB as per the SCSI standard. 20 * fixed-length means: commands that their size can be determined 21 * by their opcode and the CDB does not carry a length specifier, (unlike 22 * the VARIABLE_LENGTH_CMD(0x7f) command). This is actually not exactly 23 * true and the SCSI standard also defines extended commands and 24 * vendor specific commands that can be bigger than 16 bytes. The kernel 25 * will support these using the same infrastructure used for VARLEN CDB's. 26 * So in effect MAX_COMMAND_SIZE means the maximum size command scsi-ml 27 * supports without specifying a cmd_len by ULD's 28 */ 29 #define MAX_COMMAND_SIZE 16 30 #if (MAX_COMMAND_SIZE > BLK_MAX_CDB) 31 # error MAX_COMMAND_SIZE can not be bigger than BLK_MAX_CDB 32 #endif 33 34 struct scsi_data_buffer { 35 struct sg_table table; 36 unsigned length; 37 }; 38 39 /* embedded in scsi_cmnd */ 40 struct scsi_pointer { 41 char *ptr; /* data pointer */ 42 int this_residual; /* left in this buffer */ 43 struct scatterlist *buffer; /* which buffer */ 44 int buffers_residual; /* how many buffers left */ 45 46 dma_addr_t dma_handle; 47 48 volatile int Status; 49 volatile int Message; 50 volatile int have_data_in; 51 volatile int sent_command; 52 volatile int phase; 53 }; 54 55 /* for scmd->flags */ 56 #define SCMD_TAGGED (1 << 0) 57 #define SCMD_INITIALIZED (1 << 1) 58 #define SCMD_LAST (1 << 2) 59 /* flags preserved across unprep / reprep */ 60 #define SCMD_PRESERVED_FLAGS (SCMD_INITIALIZED) 61 62 /* for scmd->state */ 63 #define SCMD_STATE_COMPLETE 0 64 #define SCMD_STATE_INFLIGHT 1 65 66 enum scsi_cmnd_submitter { 67 SUBMITTED_BY_BLOCK_LAYER = 0, 68 SUBMITTED_BY_SCSI_ERROR_HANDLER = 1, 69 SUBMITTED_BY_SCSI_RESET_IOCTL = 2, 70 } __packed; 71 72 struct scsi_cmnd { 73 struct scsi_request req; 74 struct scsi_device *device; 75 struct list_head eh_entry; /* entry for the host eh_abort_list/eh_cmd_q */ 76 struct delayed_work abort_work; 77 78 struct rcu_head rcu; 79 80 int eh_eflags; /* Used by error handlr */ 81 82 int budget_token; 83 84 /* 85 * This is set to jiffies as it was when the command was first 86 * allocated. It is used to time how long the command has 87 * been outstanding 88 */ 89 unsigned long jiffies_at_alloc; 90 91 int retries; 92 int allowed; 93 94 unsigned char prot_op; 95 unsigned char prot_type; 96 unsigned char prot_flags; 97 enum scsi_cmnd_submitter submitter; 98 99 unsigned short cmd_len; 100 enum dma_data_direction sc_data_direction; 101 102 /* These elements define the operation we are about to perform */ 103 unsigned char *cmnd; 104 105 106 /* These elements define the operation we ultimately want to perform */ 107 struct scsi_data_buffer sdb; 108 struct scsi_data_buffer *prot_sdb; 109 110 unsigned underflow; /* Return error if less than 111 this amount is transferred */ 112 113 unsigned transfersize; /* How much we are guaranteed to 114 transfer with each SCSI transfer 115 (ie, between disconnect / 116 reconnects. Probably == sector 117 size */ 118 119 unsigned char *sense_buffer; 120 /* obtained by REQUEST SENSE when 121 * CHECK CONDITION is received on original 122 * command (auto-sense). Length must be 123 * SCSI_SENSE_BUFFERSIZE bytes. */ 124 125 /* 126 * The following fields can be written to by the host specific code. 127 * Everything else should be left alone. 128 */ 129 struct scsi_pointer SCp; /* Scratchpad used by some host adapters */ 130 131 unsigned char *host_scribble; /* The host adapter is allowed to 132 * call scsi_malloc and get some memory 133 * and hang it here. The host adapter 134 * is also expected to call scsi_free 135 * to release this memory. (The memory 136 * obtained by scsi_malloc is guaranteed 137 * to be at an address < 16Mb). */ 138 139 int result; /* Status code from lower level driver */ 140 int flags; /* Command flags */ 141 unsigned long state; /* Command completion state */ 142 143 unsigned int extra_len; /* length of alignment and padding */ 144 }; 145 146 /* Variant of blk_mq_rq_from_pdu() that verifies the type of its argument. */ 147 static inline struct request *scsi_cmd_to_rq(struct scsi_cmnd *scmd) 148 { 149 return blk_mq_rq_from_pdu(scmd); 150 } 151 152 /* 153 * Return the driver private allocation behind the command. 154 * Only works if cmd_size is set in the host template. 155 */ 156 static inline void *scsi_cmd_priv(struct scsi_cmnd *cmd) 157 { 158 return cmd + 1; 159 } 160 161 void scsi_done(struct scsi_cmnd *cmd); 162 163 extern void scsi_finish_command(struct scsi_cmnd *cmd); 164 165 extern void *scsi_kmap_atomic_sg(struct scatterlist *sg, int sg_count, 166 size_t *offset, size_t *len); 167 extern void scsi_kunmap_atomic_sg(void *virt); 168 169 blk_status_t scsi_alloc_sgtables(struct scsi_cmnd *cmd); 170 void scsi_free_sgtables(struct scsi_cmnd *cmd); 171 172 #ifdef CONFIG_SCSI_DMA 173 extern int scsi_dma_map(struct scsi_cmnd *cmd); 174 extern void scsi_dma_unmap(struct scsi_cmnd *cmd); 175 #else /* !CONFIG_SCSI_DMA */ 176 static inline int scsi_dma_map(struct scsi_cmnd *cmd) { return -ENOSYS; } 177 static inline void scsi_dma_unmap(struct scsi_cmnd *cmd) { } 178 #endif /* !CONFIG_SCSI_DMA */ 179 180 static inline unsigned scsi_sg_count(struct scsi_cmnd *cmd) 181 { 182 return cmd->sdb.table.nents; 183 } 184 185 static inline struct scatterlist *scsi_sglist(struct scsi_cmnd *cmd) 186 { 187 return cmd->sdb.table.sgl; 188 } 189 190 static inline unsigned scsi_bufflen(struct scsi_cmnd *cmd) 191 { 192 return cmd->sdb.length; 193 } 194 195 static inline void scsi_set_resid(struct scsi_cmnd *cmd, unsigned int resid) 196 { 197 cmd->req.resid_len = resid; 198 } 199 200 static inline unsigned int scsi_get_resid(struct scsi_cmnd *cmd) 201 { 202 return cmd->req.resid_len; 203 } 204 205 #define scsi_for_each_sg(cmd, sg, nseg, __i) \ 206 for_each_sg(scsi_sglist(cmd), sg, nseg, __i) 207 208 static inline int scsi_sg_copy_from_buffer(struct scsi_cmnd *cmd, 209 void *buf, int buflen) 210 { 211 return sg_copy_from_buffer(scsi_sglist(cmd), scsi_sg_count(cmd), 212 buf, buflen); 213 } 214 215 static inline int scsi_sg_copy_to_buffer(struct scsi_cmnd *cmd, 216 void *buf, int buflen) 217 { 218 return sg_copy_to_buffer(scsi_sglist(cmd), scsi_sg_count(cmd), 219 buf, buflen); 220 } 221 222 static inline sector_t scsi_get_sector(struct scsi_cmnd *scmd) 223 { 224 return blk_rq_pos(scsi_cmd_to_rq(scmd)); 225 } 226 227 static inline sector_t scsi_get_lba(struct scsi_cmnd *scmd) 228 { 229 unsigned int shift = ilog2(scmd->device->sector_size) - SECTOR_SHIFT; 230 231 return blk_rq_pos(scsi_cmd_to_rq(scmd)) >> shift; 232 } 233 234 static inline unsigned int scsi_logical_block_count(struct scsi_cmnd *scmd) 235 { 236 unsigned int shift = ilog2(scmd->device->sector_size) - SECTOR_SHIFT; 237 238 return blk_rq_bytes(scsi_cmd_to_rq(scmd)) >> shift; 239 } 240 241 /* 242 * The operations below are hints that tell the controller driver how 243 * to handle I/Os with DIF or similar types of protection information. 244 */ 245 enum scsi_prot_operations { 246 /* Normal I/O */ 247 SCSI_PROT_NORMAL = 0, 248 249 /* OS-HBA: Protected, HBA-Target: Unprotected */ 250 SCSI_PROT_READ_INSERT, 251 SCSI_PROT_WRITE_STRIP, 252 253 /* OS-HBA: Unprotected, HBA-Target: Protected */ 254 SCSI_PROT_READ_STRIP, 255 SCSI_PROT_WRITE_INSERT, 256 257 /* OS-HBA: Protected, HBA-Target: Protected */ 258 SCSI_PROT_READ_PASS, 259 SCSI_PROT_WRITE_PASS, 260 }; 261 262 static inline void scsi_set_prot_op(struct scsi_cmnd *scmd, unsigned char op) 263 { 264 scmd->prot_op = op; 265 } 266 267 static inline unsigned char scsi_get_prot_op(struct scsi_cmnd *scmd) 268 { 269 return scmd->prot_op; 270 } 271 272 enum scsi_prot_flags { 273 SCSI_PROT_TRANSFER_PI = 1 << 0, 274 SCSI_PROT_GUARD_CHECK = 1 << 1, 275 SCSI_PROT_REF_CHECK = 1 << 2, 276 SCSI_PROT_REF_INCREMENT = 1 << 3, 277 SCSI_PROT_IP_CHECKSUM = 1 << 4, 278 }; 279 280 /* 281 * The controller usually does not know anything about the target it 282 * is communicating with. However, when DIX is enabled the controller 283 * must be know target type so it can verify the protection 284 * information passed along with the I/O. 285 */ 286 enum scsi_prot_target_type { 287 SCSI_PROT_DIF_TYPE0 = 0, 288 SCSI_PROT_DIF_TYPE1, 289 SCSI_PROT_DIF_TYPE2, 290 SCSI_PROT_DIF_TYPE3, 291 }; 292 293 static inline void scsi_set_prot_type(struct scsi_cmnd *scmd, unsigned char type) 294 { 295 scmd->prot_type = type; 296 } 297 298 static inline unsigned char scsi_get_prot_type(struct scsi_cmnd *scmd) 299 { 300 return scmd->prot_type; 301 } 302 303 static inline u32 scsi_prot_ref_tag(struct scsi_cmnd *scmd) 304 { 305 struct request *rq = blk_mq_rq_from_pdu(scmd); 306 307 return t10_pi_ref_tag(rq); 308 } 309 310 static inline unsigned int scsi_prot_interval(struct scsi_cmnd *scmd) 311 { 312 return scmd->device->sector_size; 313 } 314 315 static inline unsigned scsi_prot_sg_count(struct scsi_cmnd *cmd) 316 { 317 return cmd->prot_sdb ? cmd->prot_sdb->table.nents : 0; 318 } 319 320 static inline struct scatterlist *scsi_prot_sglist(struct scsi_cmnd *cmd) 321 { 322 return cmd->prot_sdb ? cmd->prot_sdb->table.sgl : NULL; 323 } 324 325 static inline struct scsi_data_buffer *scsi_prot(struct scsi_cmnd *cmd) 326 { 327 return cmd->prot_sdb; 328 } 329 330 #define scsi_for_each_prot_sg(cmd, sg, nseg, __i) \ 331 for_each_sg(scsi_prot_sglist(cmd), sg, nseg, __i) 332 333 static inline void set_status_byte(struct scsi_cmnd *cmd, char status) 334 { 335 cmd->result = (cmd->result & 0xffffff00) | status; 336 } 337 338 static inline u8 get_status_byte(struct scsi_cmnd *cmd) 339 { 340 return cmd->result & 0xff; 341 } 342 343 static inline void set_host_byte(struct scsi_cmnd *cmd, char status) 344 { 345 cmd->result = (cmd->result & 0xff00ffff) | (status << 16); 346 } 347 348 static inline u8 get_host_byte(struct scsi_cmnd *cmd) 349 { 350 return (cmd->result >> 16) & 0xff; 351 } 352 353 /** 354 * scsi_msg_to_host_byte() - translate message byte 355 * 356 * Translate the SCSI parallel message byte to a matching 357 * host byte setting. A message of COMMAND_COMPLETE indicates 358 * a successful command execution, any other message indicate 359 * an error. As the messages themselves only have a meaning 360 * for the SCSI parallel protocol this function translates 361 * them into a matching host byte value for SCSI EH. 362 */ 363 static inline void scsi_msg_to_host_byte(struct scsi_cmnd *cmd, u8 msg) 364 { 365 switch (msg) { 366 case COMMAND_COMPLETE: 367 break; 368 case ABORT_TASK_SET: 369 set_host_byte(cmd, DID_ABORT); 370 break; 371 case TARGET_RESET: 372 set_host_byte(cmd, DID_RESET); 373 break; 374 default: 375 set_host_byte(cmd, DID_ERROR); 376 break; 377 } 378 } 379 380 static inline unsigned scsi_transfer_length(struct scsi_cmnd *scmd) 381 { 382 unsigned int xfer_len = scmd->sdb.length; 383 unsigned int prot_interval = scsi_prot_interval(scmd); 384 385 if (scmd->prot_flags & SCSI_PROT_TRANSFER_PI) 386 xfer_len += (xfer_len >> ilog2(prot_interval)) * 8; 387 388 return xfer_len; 389 } 390 391 extern void scsi_build_sense(struct scsi_cmnd *scmd, int desc, 392 u8 key, u8 asc, u8 ascq); 393 394 struct request *scsi_alloc_request(struct request_queue *q, 395 unsigned int op, blk_mq_req_flags_t flags); 396 397 #endif /* _SCSI_SCSI_CMND_H */ 398