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, fmt: "TapeNo\tBusID CuType/Model\t"
49 "DevType/Model\tBlkSize\tState\tOp\tMedState\n");
50 }
51 device = tape_find_device(devindex: n);
52 if (IS_ERR(ptr: device))
53 return 0;
54 spin_lock_irq(lock: get_ccwdev_lock(device->cdev));
55 seq_printf(m, fmt: "%d\t", (int) n);
56 seq_printf(m, fmt: "%-10.10s ", dev_name(&device->cdev->dev));
57 seq_printf(m, fmt: "%04X/", device->cdev->id.cu_type);
58 seq_printf(m, fmt: "%02X\t", device->cdev->id.cu_model);
59 seq_printf(m, fmt: "%04X/", device->cdev->id.dev_type);
60 seq_printf(m, fmt: "%02X\t\t", device->cdev->id.dev_model);
61 if (device->char_data.block_size == 0)
62 seq_printf(m, fmt: "auto\t");
63 else
64 seq_printf(m, fmt: "%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, fmt: "%s\t", str);
71 if (!list_empty(head: &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, fmt: "%s\t", str);
78 seq_printf(m, fmt: "%s\n", tape_med_st_verbose[device->medium_state]);
79 spin_unlock_irq(lock: 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

source code of linux/drivers/s390/char/tape_proc.c