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 */ 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 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 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 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 static int tape_proc_open(struct inode *inode, struct file *file) 109 { 110 return seq_open(file, &tape_proc_seq); 111 } 112 113 static const struct file_operations tape_proc_ops = 114 { 115 .owner = THIS_MODULE, 116 .open = tape_proc_open, 117 .read = seq_read, 118 .llseek = seq_lseek, 119 .release = seq_release, 120 }; 121 122 /* 123 * Initialize procfs stuff on startup 124 */ 125 void 126 tape_proc_init(void) 127 { 128 tape_proc_devices = 129 proc_create("tapedevices", S_IFREG | S_IRUGO | S_IWUSR, NULL, 130 &tape_proc_ops); 131 if (tape_proc_devices == NULL) { 132 return; 133 } 134 } 135 136 /* 137 * Cleanup all stuff registered to the procfs 138 */ 139 void 140 tape_proc_cleanup(void) 141 { 142 if (tape_proc_devices != NULL) 143 remove_proc_entry ("tapedevices", NULL); 144 } 145