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
26 static 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 */
34 static struct proc_dir_entry *tape_proc_devices;
35
36 /*
37 * Show function for /proc/tapedevices
38 */
tape_proc_show(struct seq_file * m,void * v)39 static 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
tape_proc_start(struct seq_file * m,loff_t * pos)84 static 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
tape_proc_next(struct seq_file * m,void * v,loff_t * pos)91 static 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
tape_proc_stop(struct seq_file * m,void * v)97 static void tape_proc_stop(struct seq_file *m, void *v)
98 {
99 }
100
101 static 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 */
111 void
tape_proc_init(void)112 tape_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 */
121 void
tape_proc_cleanup(void)122 tape_proc_cleanup(void)
123 {
124 if (tape_proc_devices != NULL)
125 remove_proc_entry ("tapedevices", NULL);
126 }
127