LXR linux/drivers/s390/char/tape

   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 *    tape device driver for S/390 and zSeries tapes.
   4 *
   5 *  S390 and zSeries version
   6 *    Copyright IBM Corp. 2001
   7 *    Author(s): Carsten Otte <cotte@de.ibm.com>
   8 *               Michael Holzheu <holzheu@de.ibm.com>
   9 *               Tuan Ngo-Anh <ngoanh@de.ibm.com>
  10 *
  11 * PROCFS Functions
  12 */
  13
  14#define KMSG_COMPONENT "tape"
  15#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
  16
  17#include <linux/module.h>
  18#include <linux/vmalloc.h>
  19#include <linux/seq_file.h>
  20#include <linux/proc_fs.h>
  21
  22#define TAPE_DBF_AREA   tape_core_dbf
  23
  24#include "tape.h"
  25
  26static const char *tape_med_st_verbose[MS_SIZE] =
  27{
  28        [MS_UNKNOWN] = "UNKNOWN ",
  29        [MS_LOADED] = "LOADED  ",
  30        [MS_UNLOADED] = "UNLOADED"
  31};
  32
  33/* our proc tapedevices entry */
  34static struct proc_dir_entry *tape_proc_devices;
  35
  36/*
  37 * Show function for /proc/tapedevices
  38 */
  39static int tape_proc_show(struct seq_file *m, void *v)
  40{
  41        struct tape_device *device;
  42        struct tape_request *request;
  43        const char *str;
  44        unsigned long n;
  45
  46        n = (unsigned long) v - 1;
  47        if (!n) {
  48                seq_printf(m, "TapeNo\tBusID      CuType/Model\t"
  49                        "DevType/Model\tBlkSize\tState\tOp\tMedState\n");
  50        }
  51        device = tape_find_device(n);
  52        if (IS_ERR(device))
  53                return 0;
  54        spin_lock_irq(get_ccwdev_lock(device->cdev));
  55        seq_printf(m, "%d\t", (int) n);
  56        seq_printf(m, "%-10.10s ", dev_name(&device->cdev->dev));
  57        seq_printf(m, "%04X/", device->cdev->id.cu_type);
  58        seq_printf(m, "%02X\t", device->cdev->id.cu_model);
  59        seq_printf(m, "%04X/", device->cdev->id.dev_type);
  60        seq_printf(m, "%02X\t\t", device->cdev->id.dev_model);
  61        if (device->char_data.block_size == 0)
  62                seq_printf(m, "auto\t");
  63        else
  64                seq_printf(m, "%i\t", device->char_data.block_size);
  65        if (device->tape_state >= 0 &&
  66            device->tape_state < TS_SIZE)
  67                str = tape_state_verbose[device->tape_state];
  68        else
  69                str = "UNKNOWN";
  70        seq_printf(m, "%s\t", str);
  71        if (!list_empty(&device->req_queue)) {
  72                request = list_entry(device->req_queue.next,
  73                                     struct tape_request, list);
  74                str = tape_op_verbose[request->op];
  75        } else
  76                str = "---";
  77        seq_printf(m, "%s\t", str);
  78        seq_printf(m, "%s\n", tape_med_st_verbose[device->medium_state]);
  79        spin_unlock_irq(get_ccwdev_lock(device->cdev));
  80        tape_put_device(device);
  81        return 0;
  82}
  83
  84static void *tape_proc_start(struct seq_file *m, loff_t *pos)
  85{
  86        if (*pos >= 256 / TAPE_MINORS_PER_DEV)
  87                return NULL;
  88        return (void *)((unsigned long) *pos + 1);
  89}
  90
  91static void *tape_proc_next(struct seq_file *m, void *v, loff_t *pos)
  92{
  93        ++*pos;
  94        return tape_proc_start(m, pos);
  95}
  96
  97static void tape_proc_stop(struct seq_file *m, void *v)
  98{
  99}
 100
 101static const struct seq_operations tape_proc_seq = {
 102        .start          = tape_proc_start,
 103        .next           = tape_proc_next,
 104        .stop           = tape_proc_stop,
 105        .show           = tape_proc_show,
 106};
 107
 108/*
 109 * Initialize procfs stuff on startup
 110 */
 111void
 112tape_proc_init(void)
 113{
 114        tape_proc_devices = proc_create_seq("tapedevices", 0444, NULL,
 115                                            &tape_proc_seq);
 116}
 117
 118/*
 119 * Cleanup all stuff registered to the procfs
 120 */
 121void
 122tape_proc_cleanup(void)
 123{
 124        if (tape_proc_devices != NULL)
 125                remove_proc_entry ("tapedevices", NULL);
 126}
 127