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, int bufsiz)
     /*  */
  97 {
  98         struct statfs tmp;
  99 
 100         tmp.f_type = PROC_SUPER_MAGIC;
 101         tmp.f_bsize = PAGE_SIZE/sizeof(long);
 102         tmp.f_blocks = 0;
 103         tmp.f_bfree = 0;
 104         tmp.f_bavail = 0;
 105         tmp.f_files = 0;
 106         tmp.f_ffree = 0;
 107         tmp.f_namelen = NAME_MAX;
 108         memcpy_tofs(buf, &tmp, bufsiz);
 109 }
 110 
 111 void proc_read_inode(struct inode * inode)
     /*  */
 112 {
 113         unsigned long ino, pid;
 114         struct task_struct * p;
 115         int i;
 116         
 117         inode->i_op = NULL;
 118         inode->i_mode = 0;
 119         inode->i_uid = 0;
 120         inode->i_gid = 0;
 121         inode->i_nlink = 1;
 122         inode->i_size = 0;
 123         inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
 124         inode->i_blocks = 0;
 125         inode->i_blksize = 1024;
 126         ino = inode->i_ino;
 127         pid = ino >> 16;
 128         p = task[0];
 129         for (i = 0; i < NR_TASKS ; i++)
 130                 if ((p = task[i]) && (p->pid == pid))
 131                         break;
 132         if (!p || i >= NR_TASKS)
 133                 return;
 134         if (ino == PROC_ROOT_INO) {
 135                 inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO;
 136                 inode->i_nlink = 2;
 137                 for (i = 1 ; i < NR_TASKS ; i++)
 138                         if (task[i])
 139                                 inode->i_nlink++;
 140                 inode->i_op = &proc_root_inode_operations;
 141                 return;
 142         }
 143 
 144 #ifdef CONFIG_IP_ACCT
 145         /* this file may be opened R/W by root to reset the accounting */
 146         if (ino == PROC_NET_IPACCT) {
 147                 inode->i_mode = S_IFREG | S_IRUGO | S_IWUSR;
 148                 inode->i_op = &proc_net_inode_operations;
 149                 return;
 150         }
 151 #endif
 152 #ifdef CONFIG_IP_FIREWALL
 153         /* these files may be opened R/W by root to reset the counters */
 154         if ((ino == PROC_NET_IPFWFWD) || (ino == PROC_NET_IPFWBLK)) {
 155                 inode->i_mode = S_IFREG | S_IRUGO | S_IWUSR;
 156                 inode->i_op = &proc_net_inode_operations;
 157                 return;
 158         }
 159 #endif
 160 
 161         /* other files within /proc/net */
 162         if ((ino >= PROC_NET_UNIX) && (ino < PROC_NET_LAST)) {
 163                 inode->i_mode = S_IFREG | S_IRUGO;
 164                 inode->i_op = &proc_net_inode_operations;
 165                 return;
 166         }
 167 
 168         if (ino == PROC_SCSI_SCSI) {
 169                 inode->i_mode = S_IFREG | S_IWUSR;
 170                 inode->i_op = &proc_scsi_inode_operations;
 171                 return;
 172         }
 173         /*
 174          * Special hook used when scsi is not present.
 175          */
 176         if (ino == PROC_SCSI_NOT_PRESENT) {
 177                 inode->i_mode = S_IFREG | S_IRUGO | S_IXUGO;
 178                 inode->i_op = &proc_scsi_inode_operations;
 179                 return;
 180         }
 181 
 182         /* files within /proc/scsi */
 183         if ((ino > PROC_SCSI_SCSI) && (ino < PROC_SCSI_FILE)) {
 184                 inode->i_nlink = 2;
 185                 inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO;
 186                 inode->i_op = &proc_scsi_inode_operations;
 187                 return;
 188         }
 189 
 190         /* files within /proc/scsi/<driver>/  */
 191         if ((ino >= PROC_SCSI_FILE) && (ino <= PROC_SCSI_LAST)) {
 192                 inode->i_mode = S_IFREG | S_IRUGO | S_IWUSR;
 193                 inode->i_op = &proc_scsi_inode_operations;
 194                 return;
 195         }
 196 
 197         if (!pid) {
 198                 switch (ino) {
 199                         case PROC_KMSG:
 200                                 inode->i_mode = S_IFREG | S_IRUSR;
 201                                 inode->i_op = &proc_kmsg_inode_operations;
 202                                 break;
 203                         case PROC_NET:
 204                                 inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO;
 205                                 inode->i_nlink = 2;
 206                                 inode->i_op = &proc_net_inode_operations;
 207                                 break;
 208                         case PROC_SCSI:
 209                                 inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO;
 210                                 inode->i_nlink = 2;
 211                                 inode->i_op = &proc_scsi_inode_operations;
 212                                 break;
 213                         case PROC_KCORE:
 214                                 inode->i_mode = S_IFREG | S_IRUSR;
 215                                 inode->i_op = &proc_kcore_inode_operations;
 216                                 inode->i_size = high_memory + PAGE_SIZE;
 217                                 break;
 218 #ifdef CONFIG_PROFILE
 219                         case PROC_PROFILE:
 220                                 inode->i_mode = S_IFREG | S_IRUGO | S_IWUSR;
 221                                 inode->i_op = &proc_profile_inode_operations;
 222                                 inode->i_size = (1+prof_len) * sizeof(unsigned long);
 223                                 break;
 224 #endif
 225                         default:
 226                                 inode->i_mode = S_IFREG | S_IRUGO;
 227                                 inode->i_op = &proc_array_inode_operations;
 228                                 break;
 229                 }
 230                 return;
 231         }
 232         ino &= 0x0000ffff;
 233         if (ino == PROC_PID_INO ||
 234             (p->dumpable && p->uid == p->euid && p->gid == p->egid)) {
 235                 inode->i_uid = p->uid;
 236                 inode->i_gid = p->gid;
 237         }
 238         switch (ino) {
 239                 case PROC_PID_INO:
 240                         inode->i_nlink = 4;
 241                         inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO;
 242                         inode->i_op = &proc_base_inode_operations;
 243                         return;
 244                 case PROC_PID_MEM:
 245                         inode->i_op = &proc_mem_inode_operations;
 246                         inode->i_mode = S_IFREG | S_IRUSR | S_IWUSR;
 247                         return;
 248                 case PROC_PID_CWD:
 249                 case PROC_PID_ROOT:
 250                 case PROC_PID_EXE:
 251                         inode->i_op = &proc_link_inode_operations;
 252                         inode->i_size = 64;
 253                         inode->i_mode = S_IFLNK | S_IRWXU;
 254                         return;
 255                 case PROC_PID_FD:
 256                         inode->i_mode = S_IFDIR | S_IRUSR | S_IXUSR;
 257                         inode->i_op = &proc_fd_inode_operations;
 258                         inode->i_nlink = 2;
 259                         return;
 260                 case PROC_PID_ENVIRON:
 261                         inode->i_mode = S_IFREG | S_IRUSR;
 262                         inode->i_op = &proc_array_inode_operations;
 263                         return;
 264                 case PROC_PID_CMDLINE:
 265                 case PROC_PID_STAT:
 266                 case PROC_PID_STATM:
 267                         inode->i_mode = S_IFREG | S_IRUGO;
 268                         inode->i_op = &proc_array_inode_operations;
 269                         return;
 270                 case PROC_PID_MAPS:
 271                         inode->i_mode = S_IFIFO | S_IRUGO;
 272                         inode->i_op = &proc_arraylong_inode_operations;
 273                         return;
 274         }
 275         switch (ino >> 8) {
 276                 case PROC_PID_FD_DIR:
 277                         ino &= 0xff;
 278                         if (ino >= NR_OPEN || !p->files->fd[ino])
 279                                 return;
 280                         inode->i_op = &proc_link_inode_operations;
 281                         inode->i_size = 64;
 282                         inode->i_mode = S_IFLNK;
 283                         if (p->files->fd[ino]->f_mode & 1)
 284                                 inode->i_mode |= S_IRUSR | S_IXUSR;
 285                         if (p->files->fd[ino]->f_mode & 2)
 286                                 inode->i_mode |= S_IWUSR | S_IXUSR;
 287                         return;
 288         }
 289         return;
 290 }
 291 
 292 void proc_write_inode(struct inode * inode)
     /*  */
 293 {
 294         inode->i_dirt=0;
 295 }
/* */
root/fs/proc/inode.c

DEFINITIONS
