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