fs/proc/root.c

/* */
This source file includes following definitions.
proc_lookuproot
proc_readroot
   1 /*
   2  *  linux/fs/proc/root.c
   3  *
   4  *  Copyright (C) 1991, 1992 Linus Torvalds
   5  *
   6  *  proc root directory handling functions
   7  */
   8 
   9 #include <asm/segment.h>
  10 
  11 #include <linux/errno.h>
  12 #include <linux/sched.h>
  13 #include <linux/proc_fs.h>
  14 #include <linux/stat.h>
  15 #include <linux/config.h>
  16 
  17 static int proc_readroot(struct inode *, struct file *, struct dirent *, int);
  18 static int proc_lookuproot(struct inode *,const char *,int,struct inode **);
  19 
  20 static struct file_operations proc_root_operations = {
  21         NULL,                   /* lseek - default */
  22         NULL,                   /* read - bad */
  23         NULL,                   /* write - bad */
  24         proc_readroot,          /* readdir */
  25         NULL,                   /* select - default */
  26         NULL,                   /* ioctl - default */
  27         NULL,                   /* mmap */
  28         NULL,                   /* no special open code */
  29         NULL,                   /* no special release code */
  30         NULL                    /* no fsync */
  31 };
  32 
  33 /*
  34  * proc directories can do almost nothing..
  35  */
  36 struct inode_operations proc_root_inode_operations = {
  37         &proc_root_operations,  /* default base directory file-ops */
  38         NULL,                   /* create */
  39         proc_lookuproot,        /* lookup */
  40         NULL,                   /* link */
  41         NULL,                   /* unlink */
  42         NULL,                   /* symlink */
  43         NULL,                   /* mkdir */
  44         NULL,                   /* rmdir */
  45         NULL,                   /* mknod */
  46         NULL,                   /* rename */
  47         NULL,                   /* readlink */
  48         NULL,                   /* follow_link */
  49         NULL,                   /* bmap */
  50         NULL,                   /* truncate */
  51         NULL                    /* permission */
  52 };
  53 
  54 static struct proc_dir_entry root_dir[] = {
  55         { PROC_ROOT_INO,        1, "." },
  56         { PROC_ROOT_INO,        2, ".." },
  57         { PROC_LOADAVG,         7, "loadavg" },
  58         { PROC_UPTIME,          6, "uptime" },
  59         { PROC_MEMINFO,         7, "meminfo" },
  60         { PROC_KMSG,            4, "kmsg" },
  61         { PROC_VERSION,         7, "version" },
  62         { PROC_SELF,            4, "self" },    /* will change inode # */
  63         { PROC_NET,             3, "net" },
  64 #ifdef CONFIG_DEBUG_MALLOC
  65         { PROC_MALLOC,          6, "malloc" },
  66 #endif
  67         { PROC_KCORE,           5, "kcore" },
  68         { PROC_MODULES,         7, "modules" },
  69         { PROC_STAT,            4, "stat" },
  70         { PROC_DEVICES,         7, "devices" },
  71         { PROC_INTERRUPTS,      10,"interrupts" },
  72         { PROC_FILESYSTEMS,     11,"filesystems" },
  73         { PROC_KSYMS,           5, "ksyms" },
  74         { PROC_DMA,             3, "dma" },
  75 };
  76 
  77 #define NR_ROOT_DIRENTRY ((sizeof (root_dir))/(sizeof (root_dir[0])))
  78 
  79 static int proc_lookuproot(struct inode * dir,const char * name, int len,
     /*  */
  80         struct inode ** result)
  81 {
  82         unsigned int pid, c;
  83         int i, ino;
  84 
  85         *result = NULL;
  86         if (!dir)
  87                 return -ENOENT;
  88         if (!S_ISDIR(dir->i_mode)) {
  89                 iput(dir);
  90                 return -ENOENT;
  91         }
  92         i = NR_ROOT_DIRENTRY;
  93         while (i-- > 0 && !proc_match(len,name,root_dir+i))
  94                 /* nothing */;
  95         if (i >= 0) {
  96                 ino = root_dir[i].low_ino;
  97                 if (ino == 1) {
  98                         *result = dir;
  99                         return 0;
 100                 }
 101                 if (ino == 7) /* self modifying inode ... */
 102                         ino = (current->pid << 16) + 2;
 103         } else {
 104                 pid = 0;
 105                 while (len-- > 0) {
 106                         c = *name - '0';
 107                         name++;
 108                         if (c > 9) {
 109                                 pid = 0;
 110                                 break;
 111                         }
 112                         pid *= 10;
 113                         pid += c;
 114                         if (pid & 0xffff0000) {
 115                                 pid = 0;
 116                                 break;
 117                         }
 118                 }
 119                 for (i = 0 ; i < NR_TASKS ; i++)
 120                         if (task[i] && task[i]->pid == pid)
 121                                 break;
 122                 if (!pid || i >= NR_TASKS) {
 123                         iput(dir);
 124                         return -ENOENT;
 125                 }
 126                 ino = (pid << 16) + 2;
 127         }
 128         if (!(*result = iget(dir->i_sb,ino))) {
 129                 iput(dir);
 130                 return -ENOENT;
 131         }
 132         iput(dir);
 133         return 0;
 134 }
 135 
 136 static int proc_readroot(struct inode * inode, struct file * filp,
     /*  */
 137         struct dirent * dirent, int count)
 138 {
 139         struct task_struct * p;
 140         unsigned int nr,pid;
 141         int i,j;
 142 
 143         if (!inode || !S_ISDIR(inode->i_mode))
 144                 return -EBADF;
 145 repeat:
 146         nr = filp->f_pos;
 147         if (nr < NR_ROOT_DIRENTRY) {
 148                 struct proc_dir_entry * de = root_dir + nr;
 149 
 150                 filp->f_pos++;
 151                 i = de->namelen;
 152                 put_fs_long(de->low_ino, &dirent->d_ino);
 153                 put_fs_word(i,&dirent->d_reclen);
 154                 put_fs_byte(0,i+dirent->d_name);
 155                 j = i;
 156                 while (i--)
 157                         put_fs_byte(de->name[i], i+dirent->d_name);
 158                 return j;
 159         }
 160         nr -= NR_ROOT_DIRENTRY;
 161         if (nr >= NR_TASKS)
 162                 return 0;
 163         filp->f_pos++;
 164         p = task[nr];
 165         if (!p || !(pid = p->pid))
 166                 goto repeat;
 167         if (pid & 0xffff0000)
 168                 goto repeat;
 169         j = 10;
 170         i = 1;
 171         while (pid >= j) {
 172                 j *= 10;
 173                 i++;
 174         }
 175         j = i;
 176         put_fs_long((pid << 16)+2, &dirent->d_ino);
 177         put_fs_word(i, &dirent->d_reclen);
 178         put_fs_byte(0, i+dirent->d_name);
 179         while (i--) {
 180                 put_fs_byte('0'+(pid % 10), i+dirent->d_name);
 181                 pid /= 10;
 182         }
 183         return j;
 184 }
/* */
root/fs/proc/root.c

DEFINITIONS
