xref: /openbmc/linux/drivers/s390/char/sclp_rw.h (revision 5602bf8a)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * interface to the SCLP-read/write driver
4  *
5  * Copyright IBM Corporation 1999, 2009
6  *
7  * Author(s): Martin Peschke <mpeschke@de.ibm.com>
8  *	      Martin Schwidefsky <schwidefsky@de.ibm.com>
9  */
10 
11 #ifndef __SCLP_RW_H__
12 #define __SCLP_RW_H__
13 
14 #include <linux/list.h>
15 
16 struct mto {
17 	u16 length;
18 	u16 type;
19 	u16 line_type_flags;
20 	u8  alarm_control;
21 	u8  _reserved[3];
22 } __attribute__((packed));
23 
24 struct go {
25 	u16 length;
26 	u16 type;
27 	u32 domid;
28 	u8  hhmmss_time[8];
29 	u8  th_time[3];
30 	u8  reserved_0;
31 	u8  dddyyyy_date[7];
32 	u8  _reserved_1;
33 	u16 general_msg_flags;
34 	u8  _reserved_2[10];
35 	u8  originating_system_name[8];
36 	u8  job_guest_name[8];
37 } __attribute__((packed));
38 
39 struct mdb_header {
40 	u16 length;
41 	u16 type;
42 	u32 tag;
43 	u32 revision_code;
44 } __attribute__((packed));
45 
46 struct mdb {
47 	struct mdb_header header;
48 	struct go go;
49 	struct mto mto;
50 } __attribute__((packed));
51 
52 struct msg_buf {
53 	struct evbuf_header header;
54 	struct mdb mdb;
55 } __attribute__((packed));
56 
57 /* The number of empty mto buffers that can be contained in a single sccb. */
58 #define NR_EMPTY_MSG_PER_SCCB ((PAGE_SIZE - sizeof(struct sclp_buffer) - \
59 			sizeof(struct sccb_header)) / sizeof(struct msg_buf))
60 
61 /*
62  * data structure for information about list of SCCBs (only for writing),
63  * will be located at the end of a SCCBs page
64  */
65 struct sclp_buffer {
66 	struct list_head list;		/* list_head for sccb_info chain */
67 	struct sclp_req request;
68 	void *sccb;
69 	struct msg_buf *current_msg;
70 	char *current_line;
71 	int current_length;
72 	int retry_count;
73 	/* output format settings */
74 	unsigned short columns;
75 	unsigned short htab;
76 	/* statistics about this buffer */
77 	unsigned int char_sum;		/* # chars in sccb */
78 	unsigned int messages;		/* # messages in sccb */
79 	/* Callback that is called after reaching final status. */
80 	void (*callback)(struct sclp_buffer *, int);
81 };
82 
83 int sclp_rw_init(void);
84 struct sclp_buffer *sclp_make_buffer(void *, unsigned short, unsigned short);
85 void *sclp_unmake_buffer(struct sclp_buffer *);
86 int sclp_buffer_space(struct sclp_buffer *);
87 int sclp_write(struct sclp_buffer *buffer, const unsigned char *, int);
88 int sclp_emit_buffer(struct sclp_buffer *,void (*)(struct sclp_buffer *,int));
89 unsigned int sclp_chars_in_buffer(struct sclp_buffer *);
90 
91 #endif	/* __SCLP_RW_H__ */
92