kernel/drivers/s390/char/tape_proc.c

   1 /*
   2  *    tape device driver for S/390 and zSeries tapes.
   3  *
   4  *  S390 and zSeries version
   5  *    Copyright IBM Corp. 2001
   6  *    Author(s): Carsten Otte <cotte@de.ibm.com>
   7  *               Michael Holzheu <holzheu@de.ibm.com>
   8  *               Tuan Ngo-Anh <ngoanh@de.ibm.com>
   9  *
  10  * PROCFS Functions
  11  */
  12
  13 #define KMSG_COMPONENT "tape"
  14 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
  15
  16 #include <linux/module.h>
  17 #include <linux/vmalloc.h>
  18 #include <linux/seq_file.h>
  19 #include <linux/proc_fs.h>
  20
  21 #define TAPE_DBF_AREA   tape_core_dbf
  22
  23 #include "tape.h"
  24
  25 static const char *tape_med_st_verbose[MS_SIZE] =
  26 {
  27         [MS_UNKNOWN] = "UNKNOWN ",
  28         [MS_LOADED] = "LOADED  ",
  29         [MS_UNLOADED] = "UNLOADED"
  30 };
  31
  32 /* our proc tapedevices entry */
  33 static struct proc_dir_entry *tape_proc_devices;
  34
  35 /*
  36  * Show function for /proc/tapedevices
  37  */
  38 static int tape_proc_show(struct seq_file *m, void *v)
  39 {
  40         struct tape_device *device;
  41         struct tape_request *request;
  42         const char *str;
  43         unsigned long n;
  44
  45         n = (unsigned long) v - 1;
  46         if (!n) {
  47                 seq_printf(m, "TapeNo\tBusID      CuType/Model\t"
  48                         "DevType/Model\tBlkSize\tState\tOp\tMedState\n");
  49         }
  50         device = tape_find_device(n);
  51         if (IS_ERR(device))
  52                 return 0;
  53         spin_lock_irq(get_ccwdev_lock(device->cdev));
  54         seq_printf(m, "%d\t", (int) n);
  55         seq_printf(m, "%-10.10s ", dev_name(&device->cdev->dev));
  56         seq_printf(m, "%04X/", device->cdev->id.cu_type);
  57         seq_printf(m, "%02X\t", device->cdev->id.cu_model);
  58         seq_printf(m, "%04X/", device->cdev->id.dev_type);
  59         seq_printf(m, "%02X\t\t", device->cdev->id.dev_model);
  60         if (device->char_data.block_size == 0)
  61                 seq_printf(m, "auto\t");
  62         else
  63                 seq_printf(m, "%i\t", device->char_data.block_size);
  64         if (device->tape_state >= 0 &&
  65             device->tape_state < TS_SIZE)
  66                 str = tape_state_verbose[device->tape_state];
  67         else
  68                 str = "UNKNOWN";
  69         seq_printf(m, "%s\t", str);
  70         if (!list_empty(&device->req_queue)) {
  71                 request = list_entry(device->req_queue.next,
  72                                      struct tape_request, list);
  73                 str = tape_op_verbose[request->op];
  74         } else
  75                 str = "---";
  76         seq_printf(m, "%s\t", str);
  77         seq_printf(m, "%s\n", tape_med_st_verbose[device->medium_state]);
  78         spin_unlock_irq(get_ccwdev_lock(device->cdev));
  79         tape_put_device(device);
  80         return 0;
  81 }
  82
  83 static void *tape_proc_start(struct seq_file *m, loff_t *pos)
  84 {
  85         if (*pos >= 256 / TAPE_MINORS_PER_DEV)
  86                 return NULL;
  87         return (void *)((unsigned long) *pos + 1);
  88 }
  89
  90 static void *tape_proc_next(struct seq_file *m, void *v, loff_t *pos)
  91 {
  92         ++*pos;
  93         return tape_proc_start(m, pos);
  94 }
  95
  96 static void tape_proc_stop(struct seq_file *m, void *v)
  97 {
  98 }
  99
 100 static const struct seq_operations tape_proc_seq = {
 101         .start          = tape_proc_start,
 102         .next           = tape_proc_next,
 103         .stop           = tape_proc_stop,
 104         .show           = tape_proc_show,
 105 };
 106
 107 static int tape_proc_open(struct inode *inode, struct file *file)
 108 {
 109         return seq_open(file, &tape_proc_seq);
 110 }
 111
 112 static const struct file_operations tape_proc_ops =
 113 {
 114         .owner          = THIS_MODULE,
 115         .open           = tape_proc_open,
 116         .read           = seq_read,
 117         .llseek         = seq_lseek,
 118         .release        = seq_release,
 119 };
 120
 121 /*
 122  * Initialize procfs stuff on startup
 123  */
 124 void
 125 tape_proc_init(void)
 126 {
 127         tape_proc_devices =
 128                 proc_create("tapedevices", S_IFREG | S_IRUGO | S_IWUSR, NULL,
 129                             &tape_proc_ops);
 130         if (tape_proc_devices == NULL) {
 131                 return;
 132         }
 133 }
 134
 135 /*
 136  * Cleanup all stuff registered to the procfs
 137  */
 138 void
 139 tape_proc_cleanup(void)
 140 {
 141         if (tape_proc_devices != NULL)
 142                 remove_proc_entry ("tapedevices", NULL);
 143 }