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 struct scsi_driver; 17 18 /* 19 * MAX_COMMAND_SIZE is: 20 * The longest fixed-length SCSI CDB as per the SCSI standard. 21 * fixed-length means: commands that their size can be determined 22 * by their opcode and the CDB does not carry a length specifier, (unlike 23 * the VARIABLE_LENGTH_CMD(0x7f) command). This is actually not exactly 24 * true and the SCSI standard also defines extended commands and 25 * vendor specific commands that can be bigger than 16 bytes. The kernel 26 * will support these using the same infrastructure used for VARLEN CDB's. 27 * So in effect MAX_COMMAND_SIZE means the maximum size command scsi-ml 28 * supports without specifying a cmd_len by ULD's 29 */ 30 #define MAX_COMMAND_SIZE 16 31 #if (MAX_COMMAND_SIZE > BLK_MAX_CDB) 32 # error MAX_COMMAND_SIZE can not be bigger than BLK_MAX_CDB 33 #endif 34 35 struct scsi_data_buffer { 36 struct sg_table table; 37 unsigned length; 38 }; 39 40 /* embedded in scsi_cmnd */ 41 struct scsi_pointer { 42 char *ptr; /* data pointer */ 43 int this_residual; /* left in this buffer */ 44 struct scatterlist *buffer; /* which buffer */ 45 int buffers_residual; /* how many buffers left */ 46 47 dma_addr_t dma_handle; 48 49 volatile int Status; 50 volatile int Message; 51 volatile int have_data_in; 52 volatile int sent_command; 53 volatile int phase; 54 }; 55 56 /* for scmd->flags */ 57 #define SCMD_TAGGED (1 << 0) 58 #define SCMD_INITIALIZED (1 << 1) 59 #define SCMD_LAST (1 << 2) 60 /* flags preserved across unprep / reprep */ 61 #define SCMD_PRESERVED_FLAGS (SCMD_INITIALIZED) 62 63 /* for scmd->state */ 64 #define SCMD_STATE_COMPLETE 0 65 #define SCMD_STATE_INFLIGHT 1 66 67 struct scsi_cmnd { 68 struct scsi_request req; 69 struct scsi_device *device; 70 struct list_head eh_entry; /* entry for the host eh_cmd_q */ 71 struct delayed_work abort_work; 72 73 struct rcu_head rcu; 74 75 int eh_eflags; /* Used by error handlr */ 76 77 int budget_token; 78 79 /* 80 * This is set to jiffies as it was when the command was first 81 * allocated. It is used to time how long the command has 82 * been outstanding 83 */ 84 unsigned long jiffies_at_alloc; 85 86 int retries; 87 int allowed; 88 89 unsigned char prot_op; 90 unsigned char prot_type; 91 unsigned char prot_flags; 92 93 unsigned short cmd_len; 94 enum dma_data_direction sc_data_direction; 95 96 /* These elements define the operation we are about to perform */ 97 unsigned char *cmnd; 98 99 100 /* These elements define the operation we ultimately want to perform */ 101 struct scsi_data_buffer sdb; 102 struct scsi_data_buffer *prot_sdb; 103 104 unsigned underflow; /* Return error if less than 105 this amount is transferred */ 106 107 unsigned transfersize; /* How much we are guaranteed to 108 transfer with each SCSI transfer 109 (ie, between disconnect / 110 reconnects. Probably == sector 111 size */ 112 113 unsigned char *sense_buffer; 114 /* obtained by REQUEST SENSE when 115 * CHECK CONDITION is received on original 116 * command (auto-sense). Length must be 117 * SCSI_SENSE_BUFFERSIZE bytes. */ 118 119 /* Low-level done function - can be used by low-level driver to point 120 * to completion function. Not used by mid/upper level code. */ 121 void (*scsi_done) (struct scsi_cmnd *); 122 123 /* 124 * The following fields can be written to by the host specific code. 125 * Everything else should be left alone. 126 */ 127 struct scsi_pointer SCp; /* Scratchpad used by some host adapters */ 128 129 unsigned char *host_scribble; /* The host adapter is allowed to 130 * call scsi_malloc and get some memory 131 * and hang it here. The host adapter 132 * is also expected to call scsi_free 133 * to release this memory. (The memory 134 * obtained by scsi_malloc is guaranteed 135 * to be at an address < 16Mb). */ 136 137 int result; /* Status code from lower level driver */ 138 int flags; /* Command flags */ 139 unsigned long state; /* Command completion state */ 140 141 unsigned int extra_len; /* length of alignment and padding */ 142 }; 143 144 /* Variant of blk_mq_rq_from_pdu() that verifies the type of its argument. */ 145 static inline struct request *scsi_cmd_to_rq(struct scsi_cmnd *scmd) 146 { 147 return blk_mq_rq_from_pdu(scmd); 148 } 149 150 /* 151 * Return the driver private allocation behind the command. 152 * Only works if cmd_size is set in the host template. 153 */ 154 static inline void *scsi_cmd_priv(struct scsi_cmnd *cmd) 155 { 156 return cmd + 1; 157 } 158 159 /* make sure not to use it with passthrough commands */ 160 static inline struct scsi_driver *scsi_cmd_to_driver(struct scsi_cmnd *cmd) 161 { 162 struct request *rq = scsi_cmd_to_rq(cmd); 163 164 return *(struct scsi_driver **)rq->rq_disk->private_data; 165 } 166 167 extern void scsi_finish_command(struct scsi_cmnd *cmd); 168 169 extern void *scsi_kmap_atomic_sg(struct scatterlist *sg, int sg_count, 170 size_t *offset, size_t *len); 171 extern void scsi_kunmap_atomic_sg(void *virt); 172 173 blk_status_t scsi_alloc_sgtables(struct scsi_cmnd *cmd); 174 void scsi_free_sgtables(struct scsi_cmnd *cmd); 175 176 #ifdef CONFIG_SCSI_DMA 177 extern int scsi_dma_map(struct scsi_cmnd *cmd); 178 extern void scsi_dma_unmap(struct scsi_cmnd *cmd); 179 #else /* !CONFIG_SCSI_DMA */ 180 static inline int scsi_dma_map(struct scsi_cmnd *cmd) { return -ENOSYS; } 181 static inline void scsi_dma_unmap(struct scsi_cmnd *cmd) { } 182 #endif /* !CONFIG_SCSI_DMA */ 183 184 static inline unsigned scsi_sg_count(struct scsi_cmnd *cmd) 185 { 186 return cmd->sdb.table.nents; 187 } 188 189 static inline struct scatterlist *scsi_sglist(struct scsi_cmnd *cmd) 190 { 191 return cmd->sdb.table.sgl; 192 } 193 194 static inline unsigned scsi_bufflen(struct scsi_cmnd *cmd) 195 { 196 return cmd->sdb.length; 197 } 198 199 static inline void scsi_set_resid(struct scsi_cmnd *cmd, unsigned int resid) 200 { 201 cmd->req.resid_len = resid; 202 } 203 204 static inline unsigned int scsi_get_resid(struct scsi_cmnd *cmd) 205 { 206 return cmd->req.resid_len; 207 } 208 209 #define scsi_for_each_sg(cmd, sg, nseg, __i) \ 210 for_each_sg(scsi_sglist(cmd), sg, nseg, __i) 211 212 static inline int scsi_sg_copy_from_buffer(struct scsi_cmnd *cmd, 213 void *buf, int buflen) 214 { 215 return sg_copy_from_buffer(scsi_sglist(cmd), scsi_sg_count(cmd), 216 buf, buflen); 217 } 218 219 static inline int scsi_sg_copy_to_buffer(struct scsi_cmnd *cmd, 220 void *buf, int buflen) 221 { 222 return sg_copy_to_buffer(scsi_sglist(cmd), scsi_sg_count(cmd), 223 buf, buflen); 224 } 225 226 static inline sector_t scsi_get_sector(struct scsi_cmnd *scmd) 227 { 228 return blk_rq_pos(scsi_cmd_to_rq(scmd)); 229 } 230 231 static inline sector_t scsi_get_lba(struct scsi_cmnd *scmd) 232 { 233 unsigned int shift = ilog2(scmd->device->sector_size) - SECTOR_SHIFT; 234 235 return blk_rq_pos(scsi_cmd_to_rq(scmd)) >> shift; 236 } 237 238 static inline unsigned int scsi_logical_block_count(struct scsi_cmnd *scmd) 239 { 240 unsigned int shift = ilog2(scmd->device->sector_size) - SECTOR_SHIFT; 241 242 return blk_rq_bytes(scsi_cmd_to_rq(scmd)) >> shift; 243 } 244 245 /* 246 * The operations below are hints that tell the controller driver how 247 * to handle I/Os with DIF or similar types of protection information. 248 */ 249 enum scsi_prot_operations { 250 /* Normal I/O */ 251 SCSI_PROT_NORMAL = 0, 252 253 /* OS-HBA: Protected, HBA-Target: Unprotected */ 254 SCSI_PROT_READ_INSERT, 255 SCSI_PROT_WRITE_STRIP, 256 257 /* OS-HBA: Unprotected, HBA-Target: Protected */ 258 SCSI_PROT_READ_STRIP, 259 SCSI_PROT_WRITE_INSERT, 260 261 /* OS-HBA: Protected, HBA-Target: Protected */ 262 SCSI_PROT_READ_PASS, 263 SCSI_PROT_WRITE_PASS, 264 }; 265 266 static inline void scsi_set_prot_op(struct scsi_cmnd *scmd, unsigned char op) 267 { 268 scmd->prot_op = op; 269 } 270 271 static inline unsigned char scsi_get_prot_op(struct scsi_cmnd *scmd) 272 { 273 return scmd->prot_op; 274 } 275 276 enum scsi_prot_flags { 277 SCSI_PROT_TRANSFER_PI = 1 << 0, 278 SCSI_PROT_GUARD_CHECK = 1 << 1, 279 SCSI_PROT_REF_CHECK = 1 << 2, 280 SCSI_PROT_REF_INCREMENT = 1 << 3, 281 SCSI_PROT_IP_CHECKSUM = 1 << 4, 282 }; 283 284 /* 285 * The controller usually does not know anything about the target it 286 * is communicating with. However, when DIX is enabled the controller 287 * must be know target type so it can verify the protection 288 * information passed along with the I/O. 289 */ 290 enum scsi_prot_target_type { 291 SCSI_PROT_DIF_TYPE0 = 0, 292 SCSI_PROT_DIF_TYPE1, 293 SCSI_PROT_DIF_TYPE2, 294 SCSI_PROT_DIF_TYPE3, 295 }; 296 297 static inline void scsi_set_prot_type(struct scsi_cmnd *scmd, unsigned char type) 298 { 299 scmd->prot_type = type; 300 } 301 302 static inline unsigned char scsi_get_prot_type(struct scsi_cmnd *scmd) 303 { 304 return scmd->prot_type; 305 } 306 307 static inline u32 scsi_prot_ref_tag(struct scsi_cmnd *scmd) 308 { 309 struct request *rq = blk_mq_rq_from_pdu(scmd); 310 311 return t10_pi_ref_tag(rq); 312 } 313 314 static inline unsigned int scsi_prot_interval(struct scsi_cmnd *scmd) 315 { 316 return scmd->device->sector_size; 317 } 318 319 static inline unsigned scsi_prot_sg_count(struct scsi_cmnd *cmd) 320 { 321 return cmd->prot_sdb ? cmd->prot_sdb->table.nents : 0; 322 } 323 324 static inline struct scatterlist *scsi_prot_sglist(struct scsi_cmnd *cmd) 325 { 326 return cmd->prot_sdb ? cmd->prot_sdb->table.sgl : NULL; 327 } 328 329 static inline struct scsi_data_buffer *scsi_prot(struct scsi_cmnd *cmd) 330 { 331 return cmd->prot_sdb; 332 } 333 334 #define scsi_for_each_prot_sg(cmd, sg, nseg, __i) \ 335 for_each_sg(scsi_prot_sglist(cmd), sg, nseg, __i) 336 337 static inline void set_status_byte(struct scsi_cmnd *cmd, char status) 338 { 339 cmd->result = (cmd->result & 0xffffff00) | status; 340 } 341 342 static inline u8 get_status_byte(struct scsi_cmnd *cmd) 343 { 344 return cmd->result & 0xff; 345 } 346 347 static inline void set_host_byte(struct scsi_cmnd *cmd, char status) 348 { 349 cmd->result = (cmd->result & 0xff00ffff) | (status << 16); 350 } 351 352 static inline u8 get_host_byte(struct scsi_cmnd *cmd) 353 { 354 return (cmd->result >> 16) & 0xff; 355 } 356 357 /** 358 * scsi_msg_to_host_byte() - translate message byte 359 * 360 * Translate the SCSI parallel message byte to a matching 361 * host byte setting. A message of COMMAND_COMPLETE indicates 362 * a successful command execution, any other message indicate 363 * an error. As the messages themselves only have a meaning 364 * for the SCSI parallel protocol this function translates 365 * them into a matching host byte value for SCSI EH. 366 */ 367 static inline void scsi_msg_to_host_byte(struct scsi_cmnd *cmd, u8 msg) 368 { 369 switch (msg) { 370 case COMMAND_COMPLETE: 371 break; 372 case ABORT_TASK_SET: 373 set_host_byte(cmd, DID_ABORT); 374 break; 375 case TARGET_RESET: 376 set_host_byte(cmd, DID_RESET); 377 break; 378 default: 379 set_host_byte(cmd, DID_ERROR); 380 break; 381 } 382 } 383 384 static inline unsigned scsi_transfer_length(struct scsi_cmnd *scmd) 385 { 386 unsigned int xfer_len = scmd->sdb.length; 387 unsigned int prot_interval = scsi_prot_interval(scmd); 388 389 if (scmd->prot_flags & SCSI_PROT_TRANSFER_PI) 390 xfer_len += (xfer_len >> ilog2(prot_interval)) * 8; 391 392 return xfer_len; 393 } 394 395 extern void scsi_build_sense(struct scsi_cmnd *scmd, int desc, 396 u8 key, u8 asc, u8 ascq); 397 398 #endif /* _SCSI_SCSI_CMND_H */ 399