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 11 struct Scsi_Host; 12 struct scsi_device; 13 14 /* 15 * MAX_COMMAND_SIZE is: 16 * The longest fixed-length SCSI CDB as per the SCSI standard. 17 * fixed-length means: commands that their size can be determined 18 * by their opcode and the CDB does not carry a length specifier, (unlike 19 * the VARIABLE_LENGTH_CMD(0x7f) command). This is actually not exactly 20 * true and the SCSI standard also defines extended commands and 21 * vendor specific commands that can be bigger than 16 bytes. The kernel 22 * will support these using the same infrastructure used for VARLEN CDB's. 23 * So in effect MAX_COMMAND_SIZE means the maximum size command scsi-ml 24 * supports without specifying a cmd_len by ULD's 25 */ 26 #define MAX_COMMAND_SIZE 16 27 #if (MAX_COMMAND_SIZE > BLK_MAX_CDB) 28 # error MAX_COMMAND_SIZE can not be bigger than BLK_MAX_CDB 29 #endif 30 31 struct scsi_data_buffer { 32 struct sg_table table; 33 unsigned length; 34 int resid; 35 }; 36 37 /* embedded in scsi_cmnd */ 38 struct scsi_pointer { 39 char *ptr; /* data pointer */ 40 int this_residual; /* left in this buffer */ 41 struct scatterlist *buffer; /* which buffer */ 42 int buffers_residual; /* how many buffers left */ 43 44 dma_addr_t dma_handle; 45 46 volatile int Status; 47 volatile int Message; 48 volatile int have_data_in; 49 volatile int sent_command; 50 volatile int phase; 51 }; 52 53 struct scsi_cmnd { 54 struct scsi_device *device; 55 struct list_head list; /* scsi_cmnd participates in queue lists */ 56 struct list_head eh_entry; /* entry for the host eh_cmd_q */ 57 int eh_eflags; /* Used by error handlr */ 58 59 /* 60 * A SCSI Command is assigned a nonzero serial_number before passed 61 * to the driver's queue command function. The serial_number is 62 * cleared when scsi_done is entered indicating that the command 63 * has been completed. It is a bug for LLDDs to use this number 64 * for purposes other than printk (and even that is only useful 65 * for debugging). 66 */ 67 unsigned long serial_number; 68 69 /* 70 * This is set to jiffies as it was when the command was first 71 * allocated. It is used to time how long the command has 72 * been outstanding 73 */ 74 unsigned long jiffies_at_alloc; 75 76 int retries; 77 int allowed; 78 int timeout_per_command; 79 80 unsigned short cmd_len; 81 enum dma_data_direction sc_data_direction; 82 83 /* These elements define the operation we are about to perform */ 84 unsigned char *cmnd; 85 86 struct timer_list eh_timeout; /* Used to time out the command. */ 87 88 /* These elements define the operation we ultimately want to perform */ 89 struct scsi_data_buffer sdb; 90 unsigned underflow; /* Return error if less than 91 this amount is transferred */ 92 93 unsigned transfersize; /* How much we are guaranteed to 94 transfer with each SCSI transfer 95 (ie, between disconnect / 96 reconnects. Probably == sector 97 size */ 98 99 struct request *request; /* The command we are 100 working on */ 101 102 #define SCSI_SENSE_BUFFERSIZE 96 103 unsigned char *sense_buffer; 104 /* obtained by REQUEST SENSE when 105 * CHECK CONDITION is received on original 106 * command (auto-sense) */ 107 108 /* Low-level done function - can be used by low-level driver to point 109 * to completion function. Not used by mid/upper level code. */ 110 void (*scsi_done) (struct scsi_cmnd *); 111 112 /* 113 * The following fields can be written to by the host specific code. 114 * Everything else should be left alone. 115 */ 116 struct scsi_pointer SCp; /* Scratchpad used by some host adapters */ 117 118 unsigned char *host_scribble; /* The host adapter is allowed to 119 * call scsi_malloc and get some memory 120 * and hang it here. The host adapter 121 * is also expected to call scsi_free 122 * to release this memory. (The memory 123 * obtained by scsi_malloc is guaranteed 124 * to be at an address < 16Mb). */ 125 126 int result; /* Status code from lower level driver */ 127 128 unsigned char tag; /* SCSI-II queued command tag */ 129 }; 130 131 extern struct scsi_cmnd *scsi_get_command(struct scsi_device *, gfp_t); 132 extern struct scsi_cmnd *__scsi_get_command(struct Scsi_Host *, gfp_t); 133 extern void scsi_put_command(struct scsi_cmnd *); 134 extern void __scsi_put_command(struct Scsi_Host *, struct scsi_cmnd *, 135 struct device *); 136 extern void scsi_finish_command(struct scsi_cmnd *cmd); 137 extern void scsi_req_abort_cmd(struct scsi_cmnd *cmd); 138 139 extern void *scsi_kmap_atomic_sg(struct scatterlist *sg, int sg_count, 140 size_t *offset, size_t *len); 141 extern void scsi_kunmap_atomic_sg(void *virt); 142 143 extern int scsi_init_io(struct scsi_cmnd *cmd, gfp_t gfp_mask); 144 extern void scsi_release_buffers(struct scsi_cmnd *cmd); 145 146 extern int scsi_dma_map(struct scsi_cmnd *cmd); 147 extern void scsi_dma_unmap(struct scsi_cmnd *cmd); 148 149 struct scsi_cmnd *scsi_allocate_command(gfp_t gfp_mask); 150 void scsi_free_command(gfp_t gfp_mask, struct scsi_cmnd *cmd); 151 152 static inline unsigned scsi_sg_count(struct scsi_cmnd *cmd) 153 { 154 return cmd->sdb.table.nents; 155 } 156 157 static inline struct scatterlist *scsi_sglist(struct scsi_cmnd *cmd) 158 { 159 return cmd->sdb.table.sgl; 160 } 161 162 static inline unsigned scsi_bufflen(struct scsi_cmnd *cmd) 163 { 164 return cmd->sdb.length; 165 } 166 167 static inline void scsi_set_resid(struct scsi_cmnd *cmd, int resid) 168 { 169 cmd->sdb.resid = resid; 170 } 171 172 static inline int scsi_get_resid(struct scsi_cmnd *cmd) 173 { 174 return cmd->sdb.resid; 175 } 176 177 #define scsi_for_each_sg(cmd, sg, nseg, __i) \ 178 for_each_sg(scsi_sglist(cmd), sg, nseg, __i) 179 180 static inline int scsi_bidi_cmnd(struct scsi_cmnd *cmd) 181 { 182 return blk_bidi_rq(cmd->request) && 183 (cmd->request->next_rq->special != NULL); 184 } 185 186 static inline struct scsi_data_buffer *scsi_in(struct scsi_cmnd *cmd) 187 { 188 return scsi_bidi_cmnd(cmd) ? 189 cmd->request->next_rq->special : &cmd->sdb; 190 } 191 192 static inline struct scsi_data_buffer *scsi_out(struct scsi_cmnd *cmd) 193 { 194 return &cmd->sdb; 195 } 196 197 static inline int scsi_sg_copy_from_buffer(struct scsi_cmnd *cmd, 198 void *buf, int buflen) 199 { 200 return sg_copy_from_buffer(scsi_sglist(cmd), scsi_sg_count(cmd), 201 buf, buflen); 202 } 203 204 static inline int scsi_sg_copy_to_buffer(struct scsi_cmnd *cmd, 205 void *buf, int buflen) 206 { 207 return sg_copy_to_buffer(scsi_sglist(cmd), scsi_sg_count(cmd), 208 buf, buflen); 209 } 210 211 #endif /* _SCSI_SCSI_CMND_H */ 212