1 #ifndef _SCSI_SCSI_CMND_H 2 #define _SCSI_SCSI_CMND_H 3 4 #include <linux/dma-mapping.h> 5 #include <linux/blkdev.h> 6 #include <linux/list.h> 7 #include <linux/types.h> 8 #include <linux/timer.h> 9 #include <linux/scatterlist.h> 10 #include <scsi/scsi_device.h> 11 12 struct Scsi_Host; 13 struct scsi_device; 14 struct scsi_driver; 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 #if (MAX_COMMAND_SIZE > BLK_MAX_CDB) 30 # error MAX_COMMAND_SIZE can not be bigger than BLK_MAX_CDB 31 #endif 32 33 struct scsi_data_buffer { 34 struct sg_table table; 35 unsigned length; 36 int resid; 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 struct scsi_cmnd { 56 struct scsi_device *device; 57 struct list_head list; /* scsi_cmnd participates in queue lists */ 58 struct list_head eh_entry; /* entry for the host eh_cmd_q */ 59 struct delayed_work abort_work; 60 int eh_eflags; /* Used by error handlr */ 61 62 /* 63 * A SCSI Command is assigned a nonzero serial_number before passed 64 * to the driver's queue command function. The serial_number is 65 * cleared when scsi_done is entered indicating that the command 66 * has been completed. It is a bug for LLDDs to use this number 67 * for purposes other than printk (and even that is only useful 68 * for debugging). 69 */ 70 unsigned long serial_number; 71 72 /* 73 * This is set to jiffies as it was when the command was first 74 * allocated. It is used to time how long the command has 75 * been outstanding 76 */ 77 unsigned long jiffies_at_alloc; 78 79 int retries; 80 int allowed; 81 82 unsigned char prot_op; 83 unsigned char prot_type; 84 85 unsigned short cmd_len; 86 enum dma_data_direction sc_data_direction; 87 88 /* These elements define the operation we are about to perform */ 89 unsigned char *cmnd; 90 91 92 /* These elements define the operation we ultimately want to perform */ 93 struct scsi_data_buffer sdb; 94 struct scsi_data_buffer *prot_sdb; 95 96 unsigned underflow; /* Return error if less than 97 this amount is transferred */ 98 99 unsigned transfersize; /* How much we are guaranteed to 100 transfer with each SCSI transfer 101 (ie, between disconnect / 102 reconnects. Probably == sector 103 size */ 104 105 struct request *request; /* The command we are 106 working on */ 107 108 #define SCSI_SENSE_BUFFERSIZE 96 109 unsigned char *sense_buffer; 110 /* obtained by REQUEST SENSE when 111 * CHECK CONDITION is received on original 112 * command (auto-sense) */ 113 114 /* Low-level done function - can be used by low-level driver to point 115 * to completion function. Not used by mid/upper level code. */ 116 void (*scsi_done) (struct scsi_cmnd *); 117 118 /* 119 * The following fields can be written to by the host specific code. 120 * Everything else should be left alone. 121 */ 122 struct scsi_pointer SCp; /* Scratchpad used by some host adapters */ 123 124 unsigned char *host_scribble; /* The host adapter is allowed to 125 * call scsi_malloc and get some memory 126 * and hang it here. The host adapter 127 * is also expected to call scsi_free 128 * to release this memory. (The memory 129 * obtained by scsi_malloc is guaranteed 130 * to be at an address < 16Mb). */ 131 132 int result; /* Status code from lower level driver */ 133 134 unsigned char tag; /* SCSI-II queued command tag */ 135 }; 136 137 /* 138 * Return the driver private allocation behind the command. 139 * Only works if cmd_size is set in the host template. 140 */ 141 static inline void *scsi_cmd_priv(struct scsi_cmnd *cmd) 142 { 143 return cmd + 1; 144 } 145 146 /* make sure not to use it with REQ_TYPE_BLOCK_PC commands */ 147 static inline struct scsi_driver *scsi_cmd_to_driver(struct scsi_cmnd *cmd) 148 { 149 return *(struct scsi_driver **)cmd->request->rq_disk->private_data; 150 } 151 152 extern struct scsi_cmnd *scsi_get_command(struct scsi_device *, gfp_t); 153 extern void scsi_put_command(struct scsi_cmnd *); 154 extern void scsi_finish_command(struct scsi_cmnd *cmd); 155 156 extern void *scsi_kmap_atomic_sg(struct scatterlist *sg, int sg_count, 157 size_t *offset, size_t *len); 158 extern void scsi_kunmap_atomic_sg(void *virt); 159 160 extern int scsi_init_io(struct scsi_cmnd *cmd, gfp_t gfp_mask); 161 162 extern int scsi_dma_map(struct scsi_cmnd *cmd); 163 extern void scsi_dma_unmap(struct scsi_cmnd *cmd); 164 165 static inline unsigned scsi_sg_count(struct scsi_cmnd *cmd) 166 { 167 return cmd->sdb.table.nents; 168 } 169 170 static inline struct scatterlist *scsi_sglist(struct scsi_cmnd *cmd) 171 { 172 return cmd->sdb.table.sgl; 173 } 174 175 static inline unsigned scsi_bufflen(struct scsi_cmnd *cmd) 176 { 177 return cmd->sdb.length; 178 } 179 180 static inline void scsi_set_resid(struct scsi_cmnd *cmd, int resid) 181 { 182 cmd->sdb.resid = resid; 183 } 184 185 static inline int scsi_get_resid(struct scsi_cmnd *cmd) 186 { 187 return cmd->sdb.resid; 188 } 189 190 #define scsi_for_each_sg(cmd, sg, nseg, __i) \ 191 for_each_sg(scsi_sglist(cmd), sg, nseg, __i) 192 193 static inline int scsi_bidi_cmnd(struct scsi_cmnd *cmd) 194 { 195 return blk_bidi_rq(cmd->request) && 196 (cmd->request->next_rq->special != NULL); 197 } 198 199 static inline struct scsi_data_buffer *scsi_in(struct scsi_cmnd *cmd) 200 { 201 return scsi_bidi_cmnd(cmd) ? 202 cmd->request->next_rq->special : &cmd->sdb; 203 } 204 205 static inline struct scsi_data_buffer *scsi_out(struct scsi_cmnd *cmd) 206 { 207 return &cmd->sdb; 208 } 209 210 static inline int scsi_sg_copy_from_buffer(struct scsi_cmnd *cmd, 211 void *buf, int buflen) 212 { 213 return sg_copy_from_buffer(scsi_sglist(cmd), scsi_sg_count(cmd), 214 buf, buflen); 215 } 216 217 static inline int scsi_sg_copy_to_buffer(struct scsi_cmnd *cmd, 218 void *buf, int buflen) 219 { 220 return sg_copy_to_buffer(scsi_sglist(cmd), scsi_sg_count(cmd), 221 buf, buflen); 222 } 223 224 /* 225 * The operations below are hints that tell the controller driver how 226 * to handle I/Os with DIF or similar types of protection information. 227 */ 228 enum scsi_prot_operations { 229 /* Normal I/O */ 230 SCSI_PROT_NORMAL = 0, 231 232 /* OS-HBA: Protected, HBA-Target: Unprotected */ 233 SCSI_PROT_READ_INSERT, 234 SCSI_PROT_WRITE_STRIP, 235 236 /* OS-HBA: Unprotected, HBA-Target: Protected */ 237 SCSI_PROT_READ_STRIP, 238 SCSI_PROT_WRITE_INSERT, 239 240 /* OS-HBA: Protected, HBA-Target: Protected */ 241 SCSI_PROT_READ_PASS, 242 SCSI_PROT_WRITE_PASS, 243 }; 244 245 static inline void scsi_set_prot_op(struct scsi_cmnd *scmd, unsigned char op) 246 { 247 scmd->prot_op = op; 248 } 249 250 static inline unsigned char scsi_get_prot_op(struct scsi_cmnd *scmd) 251 { 252 return scmd->prot_op; 253 } 254 255 /* 256 * The controller usually does not know anything about the target it 257 * is communicating with. However, when DIX is enabled the controller 258 * must be know target type so it can verify the protection 259 * information passed along with the I/O. 260 */ 261 enum scsi_prot_target_type { 262 SCSI_PROT_DIF_TYPE0 = 0, 263 SCSI_PROT_DIF_TYPE1, 264 SCSI_PROT_DIF_TYPE2, 265 SCSI_PROT_DIF_TYPE3, 266 }; 267 268 static inline void scsi_set_prot_type(struct scsi_cmnd *scmd, unsigned char type) 269 { 270 scmd->prot_type = type; 271 } 272 273 static inline unsigned char scsi_get_prot_type(struct scsi_cmnd *scmd) 274 { 275 return scmd->prot_type; 276 } 277 278 static inline sector_t scsi_get_lba(struct scsi_cmnd *scmd) 279 { 280 return blk_rq_pos(scmd->request); 281 } 282 283 static inline unsigned scsi_prot_sg_count(struct scsi_cmnd *cmd) 284 { 285 return cmd->prot_sdb ? cmd->prot_sdb->table.nents : 0; 286 } 287 288 static inline struct scatterlist *scsi_prot_sglist(struct scsi_cmnd *cmd) 289 { 290 return cmd->prot_sdb ? cmd->prot_sdb->table.sgl : NULL; 291 } 292 293 static inline struct scsi_data_buffer *scsi_prot(struct scsi_cmnd *cmd) 294 { 295 return cmd->prot_sdb; 296 } 297 298 #define scsi_for_each_prot_sg(cmd, sg, nseg, __i) \ 299 for_each_sg(scsi_prot_sglist(cmd), sg, nseg, __i) 300 301 static inline void set_msg_byte(struct scsi_cmnd *cmd, char status) 302 { 303 cmd->result = (cmd->result & 0xffff00ff) | (status << 8); 304 } 305 306 static inline void set_host_byte(struct scsi_cmnd *cmd, char status) 307 { 308 cmd->result = (cmd->result & 0xff00ffff) | (status << 16); 309 } 310 311 static inline void set_driver_byte(struct scsi_cmnd *cmd, char status) 312 { 313 cmd->result = (cmd->result & 0x00ffffff) | (status << 24); 314 } 315 316 static inline unsigned scsi_transfer_length(struct scsi_cmnd *scmd) 317 { 318 unsigned int xfer_len = scsi_out(scmd)->length; 319 unsigned int prot_op = scsi_get_prot_op(scmd); 320 unsigned int sector_size = scmd->device->sector_size; 321 322 switch (prot_op) { 323 case SCSI_PROT_NORMAL: 324 case SCSI_PROT_WRITE_STRIP: 325 case SCSI_PROT_READ_INSERT: 326 return xfer_len; 327 } 328 329 return xfer_len + (xfer_len >> ilog2(sector_size)) * 8; 330 } 331 332 #endif /* _SCSI_SCSI_CMND_H */ 333