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 14 struct Scsi_Host; 15 16 /* 17 * MAX_COMMAND_SIZE is: 18 * The longest fixed-length SCSI CDB as per the SCSI standard. 19 * fixed-length means: commands that their size can be determined 20 * by their opcode and the CDB does not carry a length specifier, (unlike 21 * the VARIABLE_LENGTH_CMD(0x7f) command). This is actually not exactly 22 * true and the SCSI standard also defines extended commands and 23 * vendor specific commands that can be bigger than 16 bytes. The kernel 24 * will support these using the same infrastructure used for VARLEN CDB's. 25 * So in effect MAX_COMMAND_SIZE means the maximum size command scsi-ml 26 * supports without specifying a cmd_len by ULD's 27 */ 28 #define MAX_COMMAND_SIZE 16 29 30 struct scsi_data_buffer { 31 struct sg_table table; 32 unsigned length; 33 }; 34 35 /* embedded in scsi_cmnd */ 36 struct scsi_pointer { 37 char *ptr; /* data pointer */ 38 int this_residual; /* left in this buffer */ 39 struct scatterlist *buffer; /* which buffer */ 40 int buffers_residual; /* how many buffers left */ 41 42 dma_addr_t dma_handle; 43 44 volatile int Status; 45 volatile int Message; 46 volatile int have_data_in; 47 volatile int sent_command; 48 volatile int phase; 49 }; 50 51 /* for scmd->flags */ 52 #define SCMD_TAGGED (1 << 0) 53 #define SCMD_INITIALIZED (1 << 1) 54 #define SCMD_LAST (1 << 2) 55 /* 56 * libata uses SCSI EH to fetch sense data for successful commands. 57 * SCSI EH should not overwrite scmd->result when SCMD_FORCE_EH_SUCCESS is set. 58 */ 59 #define SCMD_FORCE_EH_SUCCESS (1 << 3) 60 #define SCMD_FAIL_IF_RECOVERING (1 << 4) 61 /* flags preserved across unprep / reprep */ 62 #define SCMD_PRESERVED_FLAGS (SCMD_INITIALIZED | SCMD_FAIL_IF_RECOVERING) 63 64 /* for scmd->state */ 65 #define SCMD_STATE_COMPLETE 0 66 #define SCMD_STATE_INFLIGHT 1 67 68 enum scsi_cmnd_submitter { 69 SUBMITTED_BY_BLOCK_LAYER = 0, 70 SUBMITTED_BY_SCSI_ERROR_HANDLER = 1, 71 SUBMITTED_BY_SCSI_RESET_IOCTL = 2, 72 } __packed; 73 74 struct scsi_cmnd { 75 struct scsi_device *device; 76 struct list_head eh_entry; /* entry for the host eh_abort_list/eh_cmd_q */ 77 struct delayed_work abort_work; 78 79 struct rcu_head rcu; 80 81 int eh_eflags; /* Used by error handlr */ 82 83 int budget_token; 84 85 /* 86 * This is set to jiffies as it was when the command was first 87 * allocated. It is used to time how long the command has 88 * been outstanding 89 */ 90 unsigned long jiffies_at_alloc; 91 92 int retries; 93 int allowed; 94 95 unsigned char prot_op; 96 unsigned char prot_type; 97 unsigned char prot_flags; 98 enum scsi_cmnd_submitter submitter; 99 100 unsigned short cmd_len; 101 enum dma_data_direction sc_data_direction; 102 103 unsigned char cmnd[32]; /* SCSI CDB */ 104 105 /* These elements define the operation we ultimately want to perform */ 106 struct scsi_data_buffer sdb; 107 struct scsi_data_buffer *prot_sdb; 108 109 unsigned underflow; /* Return error if less than 110 this amount is transferred */ 111 112 unsigned transfersize; /* How much we are guaranteed to 113 transfer with each SCSI transfer 114 (ie, between disconnect / 115 reconnects. Probably == sector 116 size */ 117 unsigned resid_len; /* residual count */ 118 unsigned sense_len; 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 int flags; /* Command flags */ 126 unsigned long state; /* Command completion state */ 127 128 unsigned int extra_len; /* length of alignment and padding */ 129 130 /* 131 * The fields below can be modified by the LLD but the fields above 132 * must not be modified. 133 */ 134 135 unsigned char *host_scribble; /* The host adapter is allowed to 136 * call scsi_malloc and get some memory 137 * and hang it here. The host adapter 138 * is also expected to call scsi_free 139 * to release this memory. (The memory 140 * obtained by scsi_malloc is guaranteed 141 * to be at an address < 16Mb). */ 142 143 int result; /* Status code from lower level driver */ 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 void scsi_done_direct(struct scsi_cmnd *cmd); 163 164 extern void scsi_finish_command(struct scsi_cmnd *cmd); 165 166 extern void *scsi_kmap_atomic_sg(struct scatterlist *sg, int sg_count, 167 size_t *offset, size_t *len); 168 extern void scsi_kunmap_atomic_sg(void *virt); 169 170 blk_status_t scsi_alloc_sgtables(struct scsi_cmnd *cmd); 171 void scsi_free_sgtables(struct scsi_cmnd *cmd); 172 173 #ifdef CONFIG_SCSI_DMA 174 extern int scsi_dma_map(struct scsi_cmnd *cmd); 175 extern void scsi_dma_unmap(struct scsi_cmnd *cmd); 176 #else /* !CONFIG_SCSI_DMA */ 177 static inline int scsi_dma_map(struct scsi_cmnd *cmd) { return -ENOSYS; } 178 static inline void scsi_dma_unmap(struct scsi_cmnd *cmd) { } 179 #endif /* !CONFIG_SCSI_DMA */ 180 181 static inline unsigned scsi_sg_count(struct scsi_cmnd *cmd) 182 { 183 return cmd->sdb.table.nents; 184 } 185 186 static inline struct scatterlist *scsi_sglist(struct scsi_cmnd *cmd) 187 { 188 return cmd->sdb.table.sgl; 189 } 190 191 static inline unsigned scsi_bufflen(struct scsi_cmnd *cmd) 192 { 193 return cmd->sdb.length; 194 } 195 196 static inline void scsi_set_resid(struct scsi_cmnd *cmd, unsigned int resid) 197 { 198 cmd->resid_len = resid; 199 } 200 201 static inline unsigned int scsi_get_resid(struct scsi_cmnd *cmd) 202 { 203 return cmd->resid_len; 204 } 205 206 #define scsi_for_each_sg(cmd, sg, nseg, __i) \ 207 for_each_sg(scsi_sglist(cmd), sg, nseg, __i) 208 209 static inline int scsi_sg_copy_from_buffer(struct scsi_cmnd *cmd, 210 const void *buf, int buflen) 211 { 212 return sg_copy_from_buffer(scsi_sglist(cmd), scsi_sg_count(cmd), 213 buf, buflen); 214 } 215 216 static inline int scsi_sg_copy_to_buffer(struct scsi_cmnd *cmd, 217 void *buf, int buflen) 218 { 219 return sg_copy_to_buffer(scsi_sglist(cmd), scsi_sg_count(cmd), 220 buf, buflen); 221 } 222 223 static inline sector_t scsi_get_sector(struct scsi_cmnd *scmd) 224 { 225 return blk_rq_pos(scsi_cmd_to_rq(scmd)); 226 } 227 228 static inline sector_t scsi_get_lba(struct scsi_cmnd *scmd) 229 { 230 unsigned int shift = ilog2(scmd->device->sector_size) - SECTOR_SHIFT; 231 232 return blk_rq_pos(scsi_cmd_to_rq(scmd)) >> shift; 233 } 234 235 static inline unsigned int scsi_logical_block_count(struct scsi_cmnd *scmd) 236 { 237 unsigned int shift = ilog2(scmd->device->sector_size) - SECTOR_SHIFT; 238 239 return blk_rq_bytes(scsi_cmd_to_rq(scmd)) >> shift; 240 } 241 242 /* 243 * The operations below are hints that tell the controller driver how 244 * to handle I/Os with DIF or similar types of protection information. 245 */ 246 enum scsi_prot_operations { 247 /* Normal I/O */ 248 SCSI_PROT_NORMAL = 0, 249 250 /* OS-HBA: Protected, HBA-Target: Unprotected */ 251 SCSI_PROT_READ_INSERT, 252 SCSI_PROT_WRITE_STRIP, 253 254 /* OS-HBA: Unprotected, HBA-Target: Protected */ 255 SCSI_PROT_READ_STRIP, 256 SCSI_PROT_WRITE_INSERT, 257 258 /* OS-HBA: Protected, HBA-Target: Protected */ 259 SCSI_PROT_READ_PASS, 260 SCSI_PROT_WRITE_PASS, 261 }; 262 263 static inline void scsi_set_prot_op(struct scsi_cmnd *scmd, unsigned char op) 264 { 265 scmd->prot_op = op; 266 } 267 268 static inline unsigned char scsi_get_prot_op(struct scsi_cmnd *scmd) 269 { 270 return scmd->prot_op; 271 } 272 273 enum scsi_prot_flags { 274 SCSI_PROT_TRANSFER_PI = 1 << 0, 275 SCSI_PROT_GUARD_CHECK = 1 << 1, 276 SCSI_PROT_REF_CHECK = 1 << 2, 277 SCSI_PROT_REF_INCREMENT = 1 << 3, 278 SCSI_PROT_IP_CHECKSUM = 1 << 4, 279 }; 280 281 /* 282 * The controller usually does not know anything about the target it 283 * is communicating with. However, when DIX is enabled the controller 284 * must be know target type so it can verify the protection 285 * information passed along with the I/O. 286 */ 287 enum scsi_prot_target_type { 288 SCSI_PROT_DIF_TYPE0 = 0, 289 SCSI_PROT_DIF_TYPE1, 290 SCSI_PROT_DIF_TYPE2, 291 SCSI_PROT_DIF_TYPE3, 292 }; 293 294 static inline void scsi_set_prot_type(struct scsi_cmnd *scmd, unsigned char type) 295 { 296 scmd->prot_type = type; 297 } 298 299 static inline unsigned char scsi_get_prot_type(struct scsi_cmnd *scmd) 300 { 301 return scmd->prot_type; 302 } 303 304 static inline u32 scsi_prot_ref_tag(struct scsi_cmnd *scmd) 305 { 306 struct request *rq = blk_mq_rq_from_pdu(scmd); 307 308 return t10_pi_ref_tag(rq); 309 } 310 311 static inline unsigned int scsi_prot_interval(struct scsi_cmnd *scmd) 312 { 313 return scmd->device->sector_size; 314 } 315 316 static inline unsigned scsi_prot_sg_count(struct scsi_cmnd *cmd) 317 { 318 return cmd->prot_sdb ? cmd->prot_sdb->table.nents : 0; 319 } 320 321 static inline struct scatterlist *scsi_prot_sglist(struct scsi_cmnd *cmd) 322 { 323 return cmd->prot_sdb ? cmd->prot_sdb->table.sgl : NULL; 324 } 325 326 static inline struct scsi_data_buffer *scsi_prot(struct scsi_cmnd *cmd) 327 { 328 return cmd->prot_sdb; 329 } 330 331 #define scsi_for_each_prot_sg(cmd, sg, nseg, __i) \ 332 for_each_sg(scsi_prot_sglist(cmd), sg, nseg, __i) 333 334 static inline void set_status_byte(struct scsi_cmnd *cmd, char status) 335 { 336 cmd->result = (cmd->result & 0xffffff00) | status; 337 } 338 339 static inline u8 get_status_byte(struct scsi_cmnd *cmd) 340 { 341 return cmd->result & 0xff; 342 } 343 344 static inline void set_host_byte(struct scsi_cmnd *cmd, char status) 345 { 346 cmd->result = (cmd->result & 0xff00ffff) | (status << 16); 347 } 348 349 static inline u8 get_host_byte(struct scsi_cmnd *cmd) 350 { 351 return (cmd->result >> 16) & 0xff; 352 } 353 354 /** 355 * scsi_msg_to_host_byte() - translate message byte 356 * @cmd: the SCSI command 357 * @msg: the SCSI parallel message byte to translate 358 * 359 * Translate the SCSI parallel message byte to a matching 360 * host byte setting. A message of COMMAND_COMPLETE indicates 361 * a successful command execution, any other message indicate 362 * an error. As the messages themselves only have a meaning 363 * for the SCSI parallel protocol this function translates 364 * them into a matching host byte value for SCSI EH. 365 */ 366 static inline void scsi_msg_to_host_byte(struct scsi_cmnd *cmd, u8 msg) 367 { 368 switch (msg) { 369 case COMMAND_COMPLETE: 370 break; 371 case ABORT_TASK_SET: 372 set_host_byte(cmd, DID_ABORT); 373 break; 374 case TARGET_RESET: 375 set_host_byte(cmd, DID_RESET); 376 break; 377 default: 378 set_host_byte(cmd, DID_ERROR); 379 break; 380 } 381 } 382 383 static inline unsigned scsi_transfer_length(struct scsi_cmnd *scmd) 384 { 385 unsigned int xfer_len = scmd->sdb.length; 386 unsigned int prot_interval = scsi_prot_interval(scmd); 387 388 if (scmd->prot_flags & SCSI_PROT_TRANSFER_PI) 389 xfer_len += (xfer_len >> ilog2(prot_interval)) * 8; 390 391 return xfer_len; 392 } 393 394 extern void scsi_build_sense(struct scsi_cmnd *scmd, int desc, 395 u8 key, u8 asc, u8 ascq); 396 397 struct request *scsi_alloc_request(struct request_queue *q, blk_opf_t opf, 398 blk_mq_req_flags_t flags); 399 400 #endif /* _SCSI_SCSI_CMND_H */ 401