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
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