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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 #include <linux/android_kabi.h>
14 
15 struct Scsi_Host;
16 
17 /*
18  * MAX_COMMAND_SIZE is:
19  * The longest fixed-length SCSI CDB as per the SCSI standard.
20  * fixed-length means: commands that their size can be determined
21  * by their opcode and the CDB does not carry a length specifier, (unlike
22  * the VARIABLE_LENGTH_CMD(0x7f) command). This is actually not exactly
23  * true and the SCSI standard also defines extended commands and
24  * vendor specific commands that can be bigger than 16 bytes. The kernel
25  * will support these using the same infrastructure used for VARLEN CDB's.
26  * So in effect MAX_COMMAND_SIZE means the maximum size command scsi-ml
27  * supports without specifying a cmd_len by ULD's
28  */
29 #define MAX_COMMAND_SIZE 16
30 
31 struct scsi_data_buffer {
32 	struct sg_table table;
33 	unsigned length;
34 };
35 
36 /* embedded in scsi_cmnd */
37 struct scsi_pointer {
38 	char *ptr;		/* data pointer */
39 	int this_residual;	/* left in this buffer */
40 	struct scatterlist *buffer;	/* which buffer */
41 	int buffers_residual;	/* how many buffers left */
42 
43         dma_addr_t dma_handle;
44 
45 	volatile int Status;
46 	volatile int Message;
47 	volatile int have_data_in;
48 	volatile int sent_command;
49 	volatile int phase;
50 };
51 
52 /* for scmd->flags */
53 #define SCMD_TAGGED		(1 << 0)
54 #define SCMD_INITIALIZED	(1 << 1)
55 #define SCMD_LAST		(1 << 2)
56 /*
57  * libata uses SCSI EH to fetch sense data for successful commands.
58  * SCSI EH should not overwrite scmd->result when SCMD_FORCE_EH_SUCCESS is set.
59  */
60 #define SCMD_FORCE_EH_SUCCESS	(1 << 3)
61 #define SCMD_FAIL_IF_RECOVERING	(1 << 4)
62 /* flags preserved across unprep / reprep */
63 #define SCMD_PRESERVED_FLAGS	(SCMD_INITIALIZED | SCMD_FAIL_IF_RECOVERING)
64 
65 /* for scmd->state */
66 #define SCMD_STATE_COMPLETE	0
67 #define SCMD_STATE_INFLIGHT	1
68 
69 enum scsi_cmnd_submitter {
70 	SUBMITTED_BY_BLOCK_LAYER = 0,
71 	SUBMITTED_BY_SCSI_ERROR_HANDLER = 1,
72 	SUBMITTED_BY_SCSI_RESET_IOCTL = 2,
73 } __packed;
74 
75 struct scsi_cmnd {
76 	struct scsi_device *device;
77 	struct list_head eh_entry; /* entry for the host eh_abort_list/eh_cmd_q */
78 	struct delayed_work abort_work;
79 
80 	struct rcu_head rcu;
81 
82 	int eh_eflags;		/* Used by error handlr */
83 
84 	int budget_token;
85 
86 	/*
87 	 * This is set to jiffies as it was when the command was first
88 	 * allocated.  It is used to time how long the command has
89 	 * been outstanding
90 	 */
91 	unsigned long jiffies_at_alloc;
92 
93 	int retries;
94 	int allowed;
95 
96 	unsigned char prot_op;
97 	unsigned char prot_type;
98 	unsigned char prot_flags;
99 	enum scsi_cmnd_submitter submitter;
100 
101 	unsigned short cmd_len;
102 	enum dma_data_direction sc_data_direction;
103 
104 	unsigned char cmnd[32]; /* SCSI CDB */
105 
106 	/* These elements define the operation we ultimately want to perform */
107 	struct scsi_data_buffer sdb;
108 	struct scsi_data_buffer *prot_sdb;
109 
110 	unsigned underflow;	/* Return error if less than
111 				   this amount is transferred */
112 
113 	unsigned transfersize;	/* How much we are guaranteed to
114 				   transfer with each SCSI transfer
115 				   (ie, between disconnect /
116 				   reconnects.   Probably == sector
117 				   size */
118 	unsigned resid_len;	/* residual count */
119 	unsigned sense_len;
120 	unsigned char *sense_buffer;
121 				/* obtained by REQUEST SENSE when
122 				 * CHECK CONDITION is received on original
123 				 * command (auto-sense). Length must be
124 				 * SCSI_SENSE_BUFFERSIZE bytes. */
125 
126 	int flags;		/* Command flags */
127 	unsigned long state;	/* Command completion state */
128 
129 	unsigned int extra_len;	/* length of alignment and padding */
130 
131 	/*
132 	 * The fields below can be modified by the LLD but the fields above
133 	 * must not be modified.
134 	 */
135 
136 	unsigned char *host_scribble;	/* The host adapter is allowed to
137 					 * call scsi_malloc and get some memory
138 					 * and hang it here.  The host adapter
139 					 * is also expected to call scsi_free
140 					 * to release this memory.  (The memory
141 					 * obtained by scsi_malloc is guaranteed
142 					 * to be at an address < 16Mb). */
143 
144 	int result;		/* Status code from lower level driver */
145 
146 	ANDROID_KABI_RESERVE(1);
147 	ANDROID_KABI_RESERVE(2);
148 	ANDROID_KABI_RESERVE(3);
149 	ANDROID_KABI_RESERVE(4);
150 };
151 
152 /* Variant of blk_mq_rq_from_pdu() that verifies the type of its argument. */
scsi_cmd_to_rq(struct scsi_cmnd * scmd)153 static inline struct request *scsi_cmd_to_rq(struct scsi_cmnd *scmd)
154 {
155 	return blk_mq_rq_from_pdu(scmd);
156 }
157 
158 /*
159  * Return the driver private allocation behind the command.
160  * Only works if cmd_size is set in the host template.
161  */
scsi_cmd_priv(struct scsi_cmnd * cmd)162 static inline void *scsi_cmd_priv(struct scsi_cmnd *cmd)
163 {
164 	return cmd + 1;
165 }
166 
167 void scsi_done(struct scsi_cmnd *cmd);
168 void scsi_done_direct(struct scsi_cmnd *cmd);
169 
170 extern void scsi_finish_command(struct scsi_cmnd *cmd);
171 
172 extern void *scsi_kmap_atomic_sg(struct scatterlist *sg, int sg_count,
173 				 size_t *offset, size_t *len);
174 extern void scsi_kunmap_atomic_sg(void *virt);
175 
176 blk_status_t scsi_alloc_sgtables(struct scsi_cmnd *cmd);
177 void scsi_free_sgtables(struct scsi_cmnd *cmd);
178 
179 #ifdef CONFIG_SCSI_DMA
180 extern int scsi_dma_map(struct scsi_cmnd *cmd);
181 extern void scsi_dma_unmap(struct scsi_cmnd *cmd);
182 #else /* !CONFIG_SCSI_DMA */
scsi_dma_map(struct scsi_cmnd * cmd)183 static inline int scsi_dma_map(struct scsi_cmnd *cmd) { return -ENOSYS; }
scsi_dma_unmap(struct scsi_cmnd * cmd)184 static inline void scsi_dma_unmap(struct scsi_cmnd *cmd) { }
185 #endif /* !CONFIG_SCSI_DMA */
186 
scsi_sg_count(struct scsi_cmnd * cmd)187 static inline unsigned scsi_sg_count(struct scsi_cmnd *cmd)
188 {
189 	return cmd->sdb.table.nents;
190 }
191 
scsi_sglist(struct scsi_cmnd * cmd)192 static inline struct scatterlist *scsi_sglist(struct scsi_cmnd *cmd)
193 {
194 	return cmd->sdb.table.sgl;
195 }
196 
scsi_bufflen(struct scsi_cmnd * cmd)197 static inline unsigned scsi_bufflen(struct scsi_cmnd *cmd)
198 {
199 	return cmd->sdb.length;
200 }
201 
scsi_set_resid(struct scsi_cmnd * cmd,unsigned int resid)202 static inline void scsi_set_resid(struct scsi_cmnd *cmd, unsigned int resid)
203 {
204 	cmd->resid_len = resid;
205 }
206 
scsi_get_resid(struct scsi_cmnd * cmd)207 static inline unsigned int scsi_get_resid(struct scsi_cmnd *cmd)
208 {
209 	return cmd->resid_len;
210 }
211 
212 #define scsi_for_each_sg(cmd, sg, nseg, __i)			\
213 	for_each_sg(scsi_sglist(cmd), sg, nseg, __i)
214 
scsi_sg_copy_from_buffer(struct scsi_cmnd * cmd,const void * buf,int buflen)215 static inline int scsi_sg_copy_from_buffer(struct scsi_cmnd *cmd,
216 					   const void *buf, int buflen)
217 {
218 	return sg_copy_from_buffer(scsi_sglist(cmd), scsi_sg_count(cmd),
219 				   buf, buflen);
220 }
221 
scsi_sg_copy_to_buffer(struct scsi_cmnd * cmd,void * buf,int buflen)222 static inline int scsi_sg_copy_to_buffer(struct scsi_cmnd *cmd,
223 					 void *buf, int buflen)
224 {
225 	return sg_copy_to_buffer(scsi_sglist(cmd), scsi_sg_count(cmd),
226 				 buf, buflen);
227 }
228 
scsi_get_sector(struct scsi_cmnd * scmd)229 static inline sector_t scsi_get_sector(struct scsi_cmnd *scmd)
230 {
231 	return blk_rq_pos(scsi_cmd_to_rq(scmd));
232 }
233 
scsi_get_lba(struct scsi_cmnd * scmd)234 static inline sector_t scsi_get_lba(struct scsi_cmnd *scmd)
235 {
236 	unsigned int shift = ilog2(scmd->device->sector_size) - SECTOR_SHIFT;
237 
238 	return blk_rq_pos(scsi_cmd_to_rq(scmd)) >> shift;
239 }
240 
scsi_logical_block_count(struct scsi_cmnd * scmd)241 static inline unsigned int scsi_logical_block_count(struct scsi_cmnd *scmd)
242 {
243 	unsigned int shift = ilog2(scmd->device->sector_size);
244 
245 	return blk_rq_bytes(scsi_cmd_to_rq(scmd)) >> shift;
246 }
247 
248 /*
249  * The operations below are hints that tell the controller driver how
250  * to handle I/Os with DIF or similar types of protection information.
251  */
252 enum scsi_prot_operations {
253 	/* Normal I/O */
254 	SCSI_PROT_NORMAL = 0,
255 
256 	/* OS-HBA: Protected, HBA-Target: Unprotected */
257 	SCSI_PROT_READ_INSERT,
258 	SCSI_PROT_WRITE_STRIP,
259 
260 	/* OS-HBA: Unprotected, HBA-Target: Protected */
261 	SCSI_PROT_READ_STRIP,
262 	SCSI_PROT_WRITE_INSERT,
263 
264 	/* OS-HBA: Protected, HBA-Target: Protected */
265 	SCSI_PROT_READ_PASS,
266 	SCSI_PROT_WRITE_PASS,
267 };
268 
scsi_set_prot_op(struct scsi_cmnd * scmd,unsigned char op)269 static inline void scsi_set_prot_op(struct scsi_cmnd *scmd, unsigned char op)
270 {
271 	scmd->prot_op = op;
272 }
273 
scsi_get_prot_op(struct scsi_cmnd * scmd)274 static inline unsigned char scsi_get_prot_op(struct scsi_cmnd *scmd)
275 {
276 	return scmd->prot_op;
277 }
278 
279 enum scsi_prot_flags {
280 	SCSI_PROT_TRANSFER_PI		= 1 << 0,
281 	SCSI_PROT_GUARD_CHECK		= 1 << 1,
282 	SCSI_PROT_REF_CHECK		= 1 << 2,
283 	SCSI_PROT_REF_INCREMENT		= 1 << 3,
284 	SCSI_PROT_IP_CHECKSUM		= 1 << 4,
285 };
286 
287 /*
288  * The controller usually does not know anything about the target it
289  * is communicating with.  However, when DIX is enabled the controller
290  * must be know target type so it can verify the protection
291  * information passed along with the I/O.
292  */
293 enum scsi_prot_target_type {
294 	SCSI_PROT_DIF_TYPE0 = 0,
295 	SCSI_PROT_DIF_TYPE1,
296 	SCSI_PROT_DIF_TYPE2,
297 	SCSI_PROT_DIF_TYPE3,
298 };
299 
scsi_set_prot_type(struct scsi_cmnd * scmd,unsigned char type)300 static inline void scsi_set_prot_type(struct scsi_cmnd *scmd, unsigned char type)
301 {
302 	scmd->prot_type = type;
303 }
304 
scsi_get_prot_type(struct scsi_cmnd * scmd)305 static inline unsigned char scsi_get_prot_type(struct scsi_cmnd *scmd)
306 {
307 	return scmd->prot_type;
308 }
309 
scsi_prot_ref_tag(struct scsi_cmnd * scmd)310 static inline u32 scsi_prot_ref_tag(struct scsi_cmnd *scmd)
311 {
312 	struct request *rq = blk_mq_rq_from_pdu(scmd);
313 
314 	return t10_pi_ref_tag(rq);
315 }
316 
scsi_prot_interval(struct scsi_cmnd * scmd)317 static inline unsigned int scsi_prot_interval(struct scsi_cmnd *scmd)
318 {
319 	return scmd->device->sector_size;
320 }
321 
scsi_prot_sg_count(struct scsi_cmnd * cmd)322 static inline unsigned scsi_prot_sg_count(struct scsi_cmnd *cmd)
323 {
324 	return cmd->prot_sdb ? cmd->prot_sdb->table.nents : 0;
325 }
326 
scsi_prot_sglist(struct scsi_cmnd * cmd)327 static inline struct scatterlist *scsi_prot_sglist(struct scsi_cmnd *cmd)
328 {
329 	return cmd->prot_sdb ? cmd->prot_sdb->table.sgl : NULL;
330 }
331 
scsi_prot(struct scsi_cmnd * cmd)332 static inline struct scsi_data_buffer *scsi_prot(struct scsi_cmnd *cmd)
333 {
334 	return cmd->prot_sdb;
335 }
336 
337 #define scsi_for_each_prot_sg(cmd, sg, nseg, __i)		\
338 	for_each_sg(scsi_prot_sglist(cmd), sg, nseg, __i)
339 
set_status_byte(struct scsi_cmnd * cmd,char status)340 static inline void set_status_byte(struct scsi_cmnd *cmd, char status)
341 {
342 	cmd->result = (cmd->result & 0xffffff00) | status;
343 }
344 
get_status_byte(struct scsi_cmnd * cmd)345 static inline u8 get_status_byte(struct scsi_cmnd *cmd)
346 {
347 	return cmd->result & 0xff;
348 }
349 
set_host_byte(struct scsi_cmnd * cmd,char status)350 static inline void set_host_byte(struct scsi_cmnd *cmd, char status)
351 {
352 	cmd->result = (cmd->result & 0xff00ffff) | (status << 16);
353 }
354 
get_host_byte(struct scsi_cmnd * cmd)355 static inline u8 get_host_byte(struct scsi_cmnd *cmd)
356 {
357 	return (cmd->result >> 16) & 0xff;
358 }
359 
360 /**
361  * scsi_msg_to_host_byte() - translate message byte
362  * @cmd: the SCSI command
363  * @msg: the SCSI parallel message byte to translate
364  *
365  * Translate the SCSI parallel message byte to a matching
366  * host byte setting. A message of COMMAND_COMPLETE indicates
367  * a successful command execution, any other message indicate
368  * an error. As the messages themselves only have a meaning
369  * for the SCSI parallel protocol this function translates
370  * them into a matching host byte value for SCSI EH.
371  */
scsi_msg_to_host_byte(struct scsi_cmnd * cmd,u8 msg)372 static inline void scsi_msg_to_host_byte(struct scsi_cmnd *cmd, u8 msg)
373 {
374 	switch (msg) {
375 	case COMMAND_COMPLETE:
376 		break;
377 	case ABORT_TASK_SET:
378 		set_host_byte(cmd, DID_ABORT);
379 		break;
380 	case TARGET_RESET:
381 		set_host_byte(cmd, DID_RESET);
382 		break;
383 	default:
384 		set_host_byte(cmd, DID_ERROR);
385 		break;
386 	}
387 }
388 
scsi_transfer_length(struct scsi_cmnd * scmd)389 static inline unsigned scsi_transfer_length(struct scsi_cmnd *scmd)
390 {
391 	unsigned int xfer_len = scmd->sdb.length;
392 	unsigned int prot_interval = scsi_prot_interval(scmd);
393 
394 	if (scmd->prot_flags & SCSI_PROT_TRANSFER_PI)
395 		xfer_len += (xfer_len >> ilog2(prot_interval)) * 8;
396 
397 	return xfer_len;
398 }
399 
400 extern void scsi_build_sense(struct scsi_cmnd *scmd, int desc,
401 			     u8 key, u8 asc, u8 ascq);
402 
403 struct request *scsi_alloc_request(struct request_queue *q, blk_opf_t opf,
404 				   blk_mq_req_flags_t flags);
405 
406 #endif /* _SCSI_SCSI_CMND_H */
407