fs/proc/inode.c

/* */
This source file includes following definitions.
proc_put_inode
proc_put_super
parse_options
proc_read_super
proc_statfs
proc_read_inode
proc_write_inode
   1 /*
   2  *  linux/fs/proc/inode.c
   3  *
   4  *  Copyright (C) 1991, 1992  Linus Torvalds
   5  */
   6 
   7 #include <linux/sched.h>
   8 #include <linux/proc_fs.h>
   9 #include <linux/kernel.h>
  10 #include <linux/mm.h>
  11 #include <linux/string.h>
  12 #include <linux/stat.h>
  13 #include <linux/locks.h>
  14 #include <linux/limits.h>
  15 #include <linux/config.h>
  16 
  17 #include <asm/system.h>
  18 #include <asm/segment.h>
  19 
  20 extern unsigned long prof_len;
  21 
  22 void proc_put_inode(struct inode *inode)
     /*  */
  23 {
  24         if (inode->i_nlink)
  25                 return;
  26         inode->i_size = 0;
  27 }
  28 
  29 void proc_put_super(struct super_block *sb)
     /*  */
  30 {
  31         lock_super(sb);
  32         sb->s_dev = 0;
  33         unlock_super(sb);
  34 }
  35 
  36 static struct super_operations proc_sops = { 
  37         proc_read_inode,
  38         NULL,
  39         proc_write_inode,
  40         proc_put_inode,
  41         proc_put_super,
  42         NULL,
  43         proc_statfs,
  44         NULL
  45 };
  46 
  47 
  48 static int parse_options(char *options,uid_t *uid,gid_t *gid)
     /*  */
  49 {
  50         char *this_char,*value;
  51 
  52         *uid = current->uid;
  53         *gid = current->gid;
  54         if (!options) return 1;
  55         for (this_char = strtok(options,","); this_char; this_char = strtok(NULL,",")) {
  56                 if ((value = strchr(this_char,'=')) != NULL)
  57                         *value++ = 0;
  58                 if (!strcmp(this_char,"uid")) {
  59                         if (!value || !*value)
  60                                 return 0;
  61                         *uid = simple_strtoul(value,&value,0);
  62                         if (*value)
  63                                 return 0;
  64                 }
  65                 else if (!strcmp(this_char,"gid")) {
  66                         if (!value || !*value)
  67                                 return 0;
  68                         *gid = simple_strtoul(value,&value,0);
  69                         if (*value)
  70                                 return 0;
  71                 }
  72                 else return 0;
  73         }
  74         return 1;
  75 }
  76 
  77 
  78 struct super_block *proc_read_super(struct super_block *s,void *data, 
     /*  */
  79                                     int silent)
  80 {
  81         lock_super(s);
  82         s->s_blocksize = 1024;
  83         s->s_blocksize_bits = 10;
  84         s->s_magic = PROC_SUPER_MAGIC;
  85         s->s_op = &proc_sops;
  86         unlock_super(s);
  87         if (!(s->s_mounted = iget(s,PROC_ROOT_INO))) {
  88                 s->s_dev = 0;
  89                 printk("get root inode failed\n");
  90                 return NULL;
  91         }
  92         parse_options(data, &s->s_mounted->i_uid, &s->s_mounted->i_gid);
  93         return s;
  94 }
  95 
  96 void proc_statfs(struct super_block *sb, struct statfs *buf)
     /*  */
  97 {
  98         put_fs_long(PROC_SUPER_MAGIC, &buf->f_type);
  99         put_fs_long(PAGE_SIZE/sizeof(long), &buf->f_bsize);
 100         put_fs_long(0, &buf->f_blocks);
 101         put_fs_long(0, &buf->f_bfree);
 102         put_fs_long(0, &buf->f_bavail);
 103         put_fs_long(0, &buf->f_files);
 104         put_fs_long(0, &buf->f_ffree);
 105         put_fs_long(NAME_MAX, &buf->f_namelen);
 106         /* Don't know what value to put in buf->f_fsid */
 107 }
 108 
 109 void proc_read_inode(struct inode * inode)
     /*  */
 110 {
 111         unsigned long ino, pid;
 112         struct task_struct * p;
 113         int i;
 114         
 115         inode->i_op = NULL;
 116         inode->i_mode = 0;
 117         inode->i_uid = 0;
 118         inode->i_gid = 0;
 119         inode->i_nlink = 1;
 120         inode->i_size = 0;
 121         inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
 122         inode->i_blocks = 0;
 123         inode->i_blksize = 1024;
 124         ino = inode->i_ino;
 125         pid = ino >> 16;
 126         p = task[0];
 127         for (i = 0; i < NR_TASKS ; i++)
 128                 if ((p = task[i]) && (p->pid == pid))
 129                         break;
 130         if (!p || i >= NR_TASKS)
 131                 return;
 132         if (ino == PROC_ROOT_INO) {
 133                 inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO;
 134                 inode->i_nlink = 2;
 135                 for (i = 1 ; i < NR_TASKS ; i++)
 136                         if (task[i])
 137                                 inode->i_nlink++;
 138                 inode->i_op = &proc_root_inode_operations;
 139                 return;
 140         }
 141 
 142 #ifdef CONFIG_IP_ACCT
 143         /* this file may be opened R/W by root to reset the accounting */
 144         if (ino == PROC_NET_IPACCT) {
 145                 inode->i_mode = S_IFREG | S_IRUGO | S_IWUSR;
 146                 inode->i_op = &proc_net_inode_operations;
 147                 return;
 148         }
 149 #endif
 150 #ifdef CONFIG_IP_FIREWALL
 151         /* these files may be opened R/W by root to reset the counters */
 152         if ((ino == PROC_NET_IPFWFWD) || (ino == PROC_NET_IPFWBLK)) {
 153                 inode->i_mode = S_IFREG | S_IRUGO | S_IWUSR;
 154                 inode->i_op = &proc_net_inode_operations;
 155                 return;
 156         }
 157 #endif
 158 
 159         /* other files within /proc/net */
 160         if ((ino >= PROC_NET_UNIX) && (ino < PROC_NET_LAST)) {
 161                 inode->i_mode = S_IFREG | S_IRUGO;
 162                 inode->i_op = &proc_net_inode_operations;
 163                 return;
 164         }
 165 
 166         if (!pid) {
 167                 switch (ino) {
 168                         case PROC_KMSG:
 169                                 inode->i_mode = S_IFREG | S_IRUSR;
 170                                 inode->i_op = &proc_kmsg_inode_operations;
 171                                 break;
 172                         case PROC_NET:
 173                                 inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO;
 174                                 inode->i_nlink = 2;
 175                                 inode->i_op = &proc_net_inode_operations;
 176                                 break;
 177                         case PROC_KCORE:
 178                                 inode->i_mode = S_IFREG | S_IRUSR;
 179                                 inode->i_op = &proc_kcore_inode_operations;
 180                                 inode->i_size = high_memory + PAGE_SIZE;
 181                                 break;
 182 #ifdef CONFIG_PROFILE
 183                         case PROC_PROFILE:
 184                                 inode->i_mode = S_IFREG | S_IRUGO | S_IWUSR;
 185                                 inode->i_op = &proc_profile_inode_operations;
 186                                 inode->i_size = (1+prof_len) * sizeof(unsigned long);
 187                                 break;
 188 #endif
 189                         default:
 190                                 inode->i_mode = S_IFREG | S_IRUGO;
 191                                 inode->i_op = &proc_array_inode_operations;
 192                                 break;
 193                 }
 194                 return;
 195         }
 196         ino &= 0x0000ffff;
 197         inode->i_uid = p->euid;
 198         inode->i_gid = p->egid;
 199         switch (ino) {
 200                 case PROC_PID_INO:
 201                         inode->i_nlink = 4;
 202                         inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO;
 203                         inode->i_op = &proc_base_inode_operations;
 204                         return;
 205                 case PROC_PID_MEM:
 206                         inode->i_op = &proc_mem_inode_operations;
 207                         inode->i_mode = S_IFREG | S_IRUSR | S_IWUSR;
 208                         return;
 209                 case PROC_PID_CWD:
 210                 case PROC_PID_ROOT:
 211                 case PROC_PID_EXE:
 212                         inode->i_op = &proc_link_inode_operations;
 213                         inode->i_size = 64;
 214                         inode->i_mode = S_IFLNK | S_IRWXU;
 215                         return;
 216                 case PROC_PID_FD:
 217                         inode->i_mode = S_IFDIR | S_IRUSR | S_IXUSR;
 218                         inode->i_op = &proc_fd_inode_operations;
 219                         inode->i_nlink = 2;
 220                         return;
 221                 case PROC_PID_ENVIRON:
 222                         inode->i_mode = S_IFREG | S_IRUSR;
 223                         inode->i_op = &proc_array_inode_operations;
 224                         return;
 225                 case PROC_PID_CMDLINE:
 226                 case PROC_PID_STAT:
 227                 case PROC_PID_STATM:
 228                         inode->i_mode = S_IFREG | S_IRUGO;
 229                         inode->i_op = &proc_array_inode_operations;
 230                         return;
 231                 case PROC_PID_MAPS:
 232                         inode->i_mode = S_IFIFO | S_IRUGO;
 233                         inode->i_op = &proc_arraylong_inode_operations;
 234                         return;
 235         }
 236         switch (ino >> 8) {
 237                 case PROC_PID_FD_DIR:
 238                         ino &= 0xff;
 239                         if (ino >= NR_OPEN || !p->files->fd[ino])
 240                                 return;
 241                         inode->i_op = &proc_link_inode_operations;
 242                         inode->i_size = 64;
 243                         inode->i_mode = S_IFLNK;
 244                         if (p->files->fd[ino]->f_mode & 1)
 245                                 inode->i_mode |= S_IRUSR | S_IXUSR;
 246                         if (p->files->fd[ino]->f_mode & 2)
 247                                 inode->i_mode |= S_IWUSR | S_IXUSR;
 248                         return;
 249         }
 250         return;
 251 }
 252 
 253 void proc_write_inode(struct inode * inode)
     /*  */
 254 {
 255         inode->i_dirt=0;
 256 }
/* */
root/fs/proc/inode.c

DEFINITIONS
