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 <scsi/scsi_request.h>
14
15struct Scsi_Host;
16struct scsi_driver;
17
18/*
19 * MAX_COMMAND_SIZE is:
20 * The longest fixed-length SCSI CDB as per the SCSI standard.
21 * fixed-length means: commands that their size can be determined
22 * by their opcode and the CDB does not carry a length specifier, (unlike
23 * the VARIABLE_LENGTH_CMD(0x7f) command). This is actually not exactly
24 * true and the SCSI standard also defines extended commands and
25 * vendor specific commands that can be bigger than 16 bytes. The kernel
26 * will support these using the same infrastructure used for VARLEN CDB's.
27 * So in effect MAX_COMMAND_SIZE means the maximum size command scsi-ml
28 * supports without specifying a cmd_len by ULD's
29 */
30#define MAX_COMMAND_SIZE 16
31#if (MAX_COMMAND_SIZE > BLK_MAX_CDB)
32# error MAX_COMMAND_SIZE can not be bigger than BLK_MAX_CDB
33#endif
34
35struct scsi_data_buffer {
36 struct sg_table table;
37 unsigned length;
38};
39
40/* embedded in scsi_cmnd */
41struct scsi_pointer {
42 char *ptr; /* data pointer */
43 int this_residual; /* left in this buffer */
44 struct scatterlist *buffer; /* which buffer */
45 int buffers_residual; /* how many buffers left */
46
47 dma_addr_t dma_handle;
48
49 volatile int Status;
50 volatile int Message;
51 volatile int have_data_in;
52 volatile int sent_command;
53 volatile int phase;
54};
55
56/* for scmd->flags */
57#define SCMD_TAGGED (1 << 0)
58#define SCMD_UNCHECKED_ISA_DMA (1 << 1)
59#define SCMD_INITIALIZED (1 << 2)
60/* flags preserved across unprep / reprep */
61#define SCMD_PRESERVED_FLAGS (SCMD_UNCHECKED_ISA_DMA | SCMD_INITIALIZED)
62
63/* for scmd->state */
64#define SCMD_STATE_COMPLETE 0
65
66struct scsi_cmnd {
67 struct scsi_request req;
68 struct scsi_device *device;
69 struct list_head list; /* scsi_cmnd participates in queue lists */
70 struct list_head eh_entry; /* entry for the host eh_cmd_q */
71 struct delayed_work abort_work;
72
73 struct rcu_head rcu;
74
75 int eh_eflags; /* Used by error handlr */
76
77 /*
78 * This is set to jiffies as it was when the command was first
79 * allocated. It is used to time how long the command has
80 * been outstanding
81 */
82 unsigned long jiffies_at_alloc;
83
84 int retries;
85 int allowed;
86
87 unsigned char prot_op;
88 unsigned char prot_type;
89 unsigned char prot_flags;
90
91 unsigned short cmd_len;
92 enum dma_data_direction sc_data_direction;
93
94 /* These elements define the operation we are about to perform */
95 unsigned char *cmnd;
96
97
98 /* These elements define the operation we ultimately want to perform */
99 struct scsi_data_buffer sdb;
100 struct scsi_data_buffer *prot_sdb;
101
102 unsigned underflow; /* Return error if less than
103 this amount is transferred */
104
105 unsigned transfersize; /* How much we are guaranteed to
106 transfer with each SCSI transfer
107 (ie, between disconnect /
108 reconnects. Probably == sector
109 size */
110
111 struct request *request; /* The command we are
112 working on */
113
114 unsigned char *sense_buffer;
115 /* obtained by REQUEST SENSE when
116 * CHECK CONDITION is received on original
117 * command (auto-sense). Length must be
118 * SCSI_SENSE_BUFFERSIZE bytes. */
119
120 /* Low-level done function - can be used by low-level driver to point
121 * to completion function. Not used by mid/upper level code. */
122 void (*scsi_done) (struct scsi_cmnd *);
123
124 /*
125 * The following fields can be written to by the host specific code.
126 * Everything else should be left alone.
127 */
128 struct scsi_pointer SCp; /* Scratchpad used by some host adapters */
129
130 unsigned char *host_scribble; /* The host adapter is allowed to
131 * call scsi_malloc and get some memory
132 * and hang it here. The host adapter
133 * is also expected to call scsi_free
134 * to release this memory. (The memory
135 * obtained by scsi_malloc is guaranteed
136 * to be at an address < 16Mb). */
137
138 int result; /* Status code from lower level driver */
139 int flags; /* Command flags */
140 unsigned long state; /* Command completion state */
141
142 unsigned char tag; /* SCSI-II queued command tag */
143};
144
145/*
146 * Return the driver private allocation behind the command.
147 * Only works if cmd_size is set in the host template.
148 */
149static inline void *scsi_cmd_priv(struct scsi_cmnd *cmd)
150{
151 return cmd + 1;
152}
153
154/* make sure not to use it with passthrough commands */
155static inline struct scsi_driver *scsi_cmd_to_driver(struct scsi_cmnd *cmd)
156{
157 return *(struct scsi_driver **)cmd->request->rq_disk->private_data;
158}
159
160extern void scsi_put_command(struct scsi_cmnd *);
161extern void scsi_finish_command(struct scsi_cmnd *cmd);
162
163extern void *scsi_kmap_atomic_sg(struct scatterlist *sg, int sg_count,
164 size_t *offset, size_t *len);
165extern void scsi_kunmap_atomic_sg(void *virt);
166
167extern blk_status_t scsi_init_io(struct scsi_cmnd *cmd);
168
169#ifdef CONFIG_SCSI_DMA
170extern int scsi_dma_map(struct scsi_cmnd *cmd);
171extern void scsi_dma_unmap(struct scsi_cmnd *cmd);
172#else /* !CONFIG_SCSI_DMA */
173static inline int scsi_dma_map(struct scsi_cmnd *cmd) { return -ENOSYS; }
174static inline void scsi_dma_unmap(struct scsi_cmnd *cmd) { }
175#endif /* !CONFIG_SCSI_DMA */
176
177static inline unsigned scsi_sg_count(struct scsi_cmnd *cmd)
178{
179 return cmd->sdb.table.nents;
180}
181
182static inline struct scatterlist *scsi_sglist(struct scsi_cmnd *cmd)
183{
184 return cmd->sdb.table.sgl;
185}
186
187static inline unsigned scsi_bufflen(struct scsi_cmnd *cmd)
188{
189 return cmd->sdb.length;
190}
191
192static inline void scsi_set_resid(struct scsi_cmnd *cmd, int resid)
193{
194 cmd->req.resid_len = resid;
195}
196
197static inline int scsi_get_resid(struct scsi_cmnd *cmd)
198{
199 return cmd->req.resid_len;
200}
201
202#define scsi_for_each_sg(cmd, sg, nseg, __i) \
203 for_each_sg(scsi_sglist(cmd), sg, nseg, __i)
204
205static inline int scsi_sg_copy_from_buffer(struct scsi_cmnd *cmd,
206 void *buf, int buflen)
207{
208 return sg_copy_from_buffer(scsi_sglist(cmd), scsi_sg_count(cmd),
209 buf, buflen);
210}
211
212static inline int scsi_sg_copy_to_buffer(struct scsi_cmnd *cmd,
213 void *buf, int buflen)
214{
215 return sg_copy_to_buffer(scsi_sglist(cmd), scsi_sg_count(cmd),
216 buf, buflen);
217}
218
219/*
220 * The operations below are hints that tell the controller driver how
221 * to handle I/Os with DIF or similar types of protection information.
222 */
223enum scsi_prot_operations {
224 /* Normal I/O */
225 SCSI_PROT_NORMAL = 0,
226
227 /* OS-HBA: Protected, HBA-Target: Unprotected */
228 SCSI_PROT_READ_INSERT,
229 SCSI_PROT_WRITE_STRIP,
230
231 /* OS-HBA: Unprotected, HBA-Target: Protected */
232 SCSI_PROT_READ_STRIP,
233 SCSI_PROT_WRITE_INSERT,
234
235 /* OS-HBA: Protected, HBA-Target: Protected */
236 SCSI_PROT_READ_PASS,
237 SCSI_PROT_WRITE_PASS,
238};
239
240static inline void scsi_set_prot_op(struct scsi_cmnd *scmd, unsigned char op)
241{
242 scmd->prot_op = op;
243}
244
245static inline unsigned char scsi_get_prot_op(struct scsi_cmnd *scmd)
246{
247 return scmd->prot_op;
248}
249
250enum scsi_prot_flags {
251 SCSI_PROT_TRANSFER_PI = 1 << 0,
252 SCSI_PROT_GUARD_CHECK = 1 << 1,
253 SCSI_PROT_REF_CHECK = 1 << 2,
254 SCSI_PROT_REF_INCREMENT = 1 << 3,
255 SCSI_PROT_IP_CHECKSUM = 1 << 4,
256};
257
258/*
259 * The controller usually does not know anything about the target it
260 * is communicating with. However, when DIX is enabled the controller
261 * must be know target type so it can verify the protection
262 * information passed along with the I/O.
263 */
264enum scsi_prot_target_type {
265 SCSI_PROT_DIF_TYPE0 = 0,
266 SCSI_PROT_DIF_TYPE1,
267 SCSI_PROT_DIF_TYPE2,
268 SCSI_PROT_DIF_TYPE3,
269};
270
271static inline void scsi_set_prot_type(struct scsi_cmnd *scmd, unsigned char type)
272{
273 scmd->prot_type = type;
274}
275
276static inline unsigned char scsi_get_prot_type(struct scsi_cmnd *scmd)
277{
278 return scmd->prot_type;
279}
280
281static inline sector_t scsi_get_lba(struct scsi_cmnd *scmd)
282{
283 return blk_rq_pos(scmd->request);
284}
285
286static inline unsigned int scsi_prot_interval(struct scsi_cmnd *scmd)
287{
288 return scmd->device->sector_size;
289}
290
291static inline unsigned scsi_prot_sg_count(struct scsi_cmnd *cmd)
292{
293 return cmd->prot_sdb ? cmd->prot_sdb->table.nents : 0;
294}
295
296static inline struct scatterlist *scsi_prot_sglist(struct scsi_cmnd *cmd)
297{
298 return cmd->prot_sdb ? cmd->prot_sdb->table.sgl : NULL;
299}
300
301static inline struct scsi_data_buffer *scsi_prot(struct scsi_cmnd *cmd)
302{
303 return cmd->prot_sdb;
304}
305
306#define scsi_for_each_prot_sg(cmd, sg, nseg, __i) \
307 for_each_sg(scsi_prot_sglist(cmd), sg, nseg, __i)
308
309static inline void set_msg_byte(struct scsi_cmnd *cmd, char status)
310{
311 cmd->result = (cmd->result & 0xffff00ff) | (status << 8);
312}
313
314static inline void set_host_byte(struct scsi_cmnd *cmd, char status)
315{
316 cmd->result = (cmd->result & 0xff00ffff) | (status << 16);
317}
318
319static inline void set_driver_byte(struct scsi_cmnd *cmd, char status)
320{
321 cmd->result = (cmd->result & 0x00ffffff) | (status << 24);
322}
323
324static inline unsigned scsi_transfer_length(struct scsi_cmnd *scmd)
325{
326 unsigned int xfer_len = scmd->sdb.length;
327 unsigned int prot_interval = scsi_prot_interval(scmd);
328
329 if (scmd->prot_flags & SCSI_PROT_TRANSFER_PI)
330 xfer_len += (xfer_len >> ilog2(prot_interval)) * 8;
331
332 return xfer_len;
333}
334
335#endif /* _SCSI_SCSI_CMND_H */
336