1 #ifndef _SCSI_SCSI_CMND_H
2 #define _SCSI_SCSI_CMND_H
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>
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
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
31 struct scsi_data_buffer
{
32 struct sg_table table
;
37 /* embedded in scsi_cmnd */
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 */
44 dma_addr_t dma_handle
;
48 volatile int have_data_in
;
49 volatile int sent_command
;
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 */
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
67 unsigned long serial_number
;
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
74 unsigned long jiffies_at_alloc
;
78 int timeout_per_command
;
80 unsigned short cmd_len
;
81 enum dma_data_direction sc_data_direction
;
83 /* These elements define the operation we are about to perform */
86 struct timer_list eh_timeout
; /* Used to time out the command. */
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 */
93 unsigned transfersize
; /* How much we are guaranteed to
94 transfer with each SCSI transfer
95 (ie, between disconnect /
96 reconnects. Probably == sector
99 struct request
*request
; /* The command we are
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) */
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
*);
113 * The following fields can be written to by the host specific code.
114 * Everything else should be left alone.
116 struct scsi_pointer SCp
; /* Scratchpad used by some host adapters */
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). */
126 int result
; /* Status code from lower level driver */
128 unsigned char tag
; /* SCSI-II queued command tag */
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
*,
136 extern void scsi_finish_command(struct scsi_cmnd
*cmd
);
137 extern void scsi_req_abort_cmd(struct scsi_cmnd
*cmd
);
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
);
143 extern int scsi_init_io(struct scsi_cmnd
*cmd
, gfp_t gfp_mask
);
144 extern void scsi_release_buffers(struct scsi_cmnd
*cmd
);
146 extern int scsi_dma_map(struct scsi_cmnd
*cmd
);
147 extern void scsi_dma_unmap(struct scsi_cmnd
*cmd
);
149 struct scsi_cmnd
*scsi_allocate_command(gfp_t gfp_mask
);
150 void scsi_free_command(gfp_t gfp_mask
, struct scsi_cmnd
*cmd
);
152 static inline unsigned scsi_sg_count(struct scsi_cmnd
*cmd
)
154 return cmd
->sdb
.table
.nents
;
157 static inline struct scatterlist
*scsi_sglist(struct scsi_cmnd
*cmd
)
159 return cmd
->sdb
.table
.sgl
;
162 static inline unsigned scsi_bufflen(struct scsi_cmnd
*cmd
)
164 return cmd
->sdb
.length
;
167 static inline void scsi_set_resid(struct scsi_cmnd
*cmd
, int resid
)
169 cmd
->sdb
.resid
= resid
;
172 static inline int scsi_get_resid(struct scsi_cmnd
*cmd
)
174 return cmd
->sdb
.resid
;
177 #define scsi_for_each_sg(cmd, sg, nseg, __i) \
178 for_each_sg(scsi_sglist(cmd), sg, nseg, __i)
180 static inline int scsi_bidi_cmnd(struct scsi_cmnd
*cmd
)
182 return blk_bidi_rq(cmd
->request
) &&
183 (cmd
->request
->next_rq
->special
!= NULL
);
186 static inline struct scsi_data_buffer
*scsi_in(struct scsi_cmnd
*cmd
)
188 return scsi_bidi_cmnd(cmd
) ?
189 cmd
->request
->next_rq
->special
: &cmd
->sdb
;
192 static inline struct scsi_data_buffer
*scsi_out(struct scsi_cmnd
*cmd
)
197 static inline int scsi_sg_copy_from_buffer(struct scsi_cmnd
*cmd
,
198 void *buf
, int buflen
)
200 return sg_copy_from_buffer(scsi_sglist(cmd
), scsi_sg_count(cmd
),
204 static inline int scsi_sg_copy_to_buffer(struct scsi_cmnd
*cmd
,
205 void *buf
, int buflen
)
207 return sg_copy_to_buffer(scsi_sglist(cmd
), scsi_sg_count(cmd
),
211 #endif /* _SCSI_SCSI_CMND_H */