LXR linux/drivers/s390/char/sclp

   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
  16struct mto {
  17        u16 length;
  18        u16 type;
  19        u16 line_type_flags;
  20        u8  alarm_control;
  21        u8  _reserved[3];
  22} __attribute__((packed));
  23
  24struct 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
  39struct mdb_header {
  40        u16 length;
  41        u16 type;
  42        u32 tag;
  43        u32 revision_code;
  44} __attribute__((packed));
  45
  46struct mdb {
  47        struct mdb_header header;
  48        struct go go;
  49        struct mto mto;
  50} __attribute__((packed));
  51
  52struct 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 */
  65struct 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
  83int sclp_rw_init(void);
  84struct sclp_buffer *sclp_make_buffer(void *, unsigned short, unsigned short);
  85void *sclp_unmake_buffer(struct sclp_buffer *);
  86int sclp_buffer_space(struct sclp_buffer *);
  87int sclp_write(struct sclp_buffer *buffer, const unsigned char *, int);
  88int sclp_emit_buffer(struct sclp_buffer *,void (*)(struct sclp_buffer *,int));
  89unsigned int sclp_chars_in_buffer(struct sclp_buffer *);
  90
  91#endif  /* __SCLP_RW_H__ */
  92