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 extern void proc_net_init(void);
  22 
  23 void proc_put_inode(struct inode *inode)
     /*  */
  24 {
  25         if (inode->i_nlink)
  26                 return;
  27         inode->i_size = 0;
  28 }
  29 
  30 void proc_put_super(struct super_block *sb)
     /*  */
  31 {
  32         lock_super(sb);
  33         sb->s_dev = 0;
  34         unlock_super(sb);
  35 }
  36 
  37 static struct super_operations proc_sops = { 
  38         proc_read_inode,
  39         NULL,
  40         proc_write_inode,
  41         proc_put_inode,
  42         proc_put_super,
  43         NULL,
  44         proc_statfs,
  45         NULL
  46 };
  47 
  48 
  49 static int parse_options(char *options,uid_t *uid,gid_t *gid)
     /*  */
  50 {
  51         char *this_char,*value;
  52 
  53         *uid = current->uid;
  54         *gid = current->gid;
  55         if (!options) return 1;
  56         for (this_char = strtok(options,","); this_char; this_char = strtok(NULL,",")) {
  57                 if ((value = strchr(this_char,'=')) != NULL)
  58                         *value++ = 0;
  59                 if (!strcmp(this_char,"uid")) {
  60                         if (!value || !*value)
  61                                 return 0;
  62                         *uid = simple_strtoul(value,&value,0);
  63                         if (*value)
  64                                 return 0;
  65                 }
  66                 else if (!strcmp(this_char,"gid")) {
  67                         if (!value || !*value)
  68                                 return 0;
  69                         *gid = simple_strtoul(value,&value,0);
  70                         if (*value)
  71                                 return 0;
  72                 }
  73                 else return 0;
  74         }
  75         return 1;
  76 }
  77 
  78 
  79 struct super_block *proc_read_super(struct super_block *s,void *data, 
     /*  */
  80                                     int silent)
  81 {
  82         lock_super(s);
  83         s->s_blocksize = 1024;
  84         s->s_blocksize_bits = 10;
  85         s->s_magic = PROC_SUPER_MAGIC;
  86         s->s_op = &proc_sops;
  87         unlock_super(s);
  88         if (!(s->s_mounted = iget(s,PROC_ROOT_INO))) {
  89                 s->s_dev = 0;
  90                 printk("get root inode failed\n");
  91                 return NULL;
  92         }
  93         parse_options(data, &s->s_mounted->i_uid, &s->s_mounted->i_gid);
  94         proc_net_init();
  95         return s;
  96 }
  97 
  98 void proc_statfs(struct super_block *sb, struct statfs *buf, int bufsiz)
     /*  */
  99 {
 100         struct statfs tmp;
 101 
 102         tmp.f_type = PROC_SUPER_MAGIC;
 103         tmp.f_bsize = PAGE_SIZE/sizeof(long);
 104         tmp.f_blocks = 0;
 105         tmp.f_bfree = 0;
 106         tmp.f_bavail = 0;
 107         tmp.f_files = 0;
 108         tmp.f_ffree = 0;
 109         tmp.f_namelen = NAME_MAX;
 110         memcpy_tofs(buf, &tmp, bufsiz);
 111 }
 112 
 113 void proc_read_inode(struct inode * inode)
     /*  */
 114 {
 115         unsigned long ino, pid;
 116         struct task_struct * p;
 117         int i;
 118         
 119         inode->i_op = NULL;
 120         inode->i_mode = 0;
 121         inode->i_uid = 0;
 122         inode->i_gid = 0;
 123         inode->i_nlink = 1;
 124         inode->i_size = 0;
 125         inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
 126         inode->i_blocks = 0;
 127         inode->i_blksize = 1024;
 128         ino = inode->i_ino;
 129         pid = ino >> 16;
 130         p = task[0];
 131         for (i = 0; i < NR_TASKS ; i++)
 132                 if ((p = task[i]) && (p->pid == pid))
 133                         break;
 134         if (!p || i >= NR_TASKS)
 135                 return;
 136         if (ino == PROC_ROOT_INO) {
 137                 inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO;
 138                 inode->i_nlink = 2;
 139                 for (i = 1 ; i < NR_TASKS ; i++)
 140                         if (task[i])
 141                                 inode->i_nlink++;
 142                 inode->i_op = &proc_root_inode_operations;
 143                 return;
 144         }
 145 
 146 /* #ifdef CONFIG_IP_ACCT */
 147         /* this file may be opened R/W by root to reset the accounting */
 148         if (ino == PROC_NET_IPACCT) {
 149                 inode->i_mode = S_IFREG | S_IRUGO | S_IWUSR;
 150                 inode->i_op = &proc_net_inode_operations;
 151                 return;
 152         }
 153 /* #endif */
 154 /* #ifdef CONFIG_IP_FIREWALL */
 155         /* these files may be opened R/W by root to reset the counters */
 156         if ((ino == PROC_NET_IPFWFWD) || (ino == PROC_NET_IPFWBLK)) {
 157                 inode->i_mode = S_IFREG | S_IRUGO | S_IWUSR;
 158                 inode->i_op = &proc_net_inode_operations;
 159                 return;
 160         }
 161 /* #endif */
 162 
 163         /* other files within /proc/net */
 164         if ((ino >= PROC_NET_UNIX) && (ino < PROC_NET_LAST)) {
 165                 inode->i_mode = S_IFREG | S_IRUGO;
 166                 inode->i_op = &proc_net_inode_operations;
 167                 return;
 168         }
 169 
 170         if (ino == PROC_SCSI_SCSI) {
 171                 inode->i_mode = S_IFREG | S_IRUGO | S_IWUSR;
 172                 inode->i_op = &proc_scsi_inode_operations;
 173                 return;
 174         }
 175         /*
 176          * Special hook used when scsi is not present.
 177          */
 178         if (ino == PROC_SCSI_NOT_PRESENT) {
 179                 inode->i_mode = S_IFREG | S_IRUGO | S_IXUGO;
 180                 inode->i_op = &proc_scsi_inode_operations;
 181                 return;
 182         }
 183 
 184         /* files within /proc/scsi */
 185         if ((ino > PROC_SCSI_SCSI) && (ino < PROC_SCSI_FILE)) {
 186                 inode->i_nlink = 2;
 187                 inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO;
 188                 inode->i_op = &proc_scsi_inode_operations;
 189                 return;
 190         }
 191 
 192         /* files within /proc/scsi/<driver>/  */
 193         if ((ino >= PROC_SCSI_FILE) && (ino <= PROC_SCSI_LAST)) {
 194                 inode->i_mode = S_IFREG | S_IRUGO | S_IWUSR;
 195                 inode->i_op = &proc_scsi_inode_operations;
 196                 return;
 197         }
 198 
 199         if (!pid) {
 200                 switch (ino) {
 201                         case PROC_KMSG:
 202                                 inode->i_mode = S_IFREG | S_IRUSR;
 203                                 inode->i_op = &proc_kmsg_inode_operations;
 204                                 break;
 205                         case PROC_NET:
 206                                 inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO;
 207                                 inode->i_nlink = 2;
 208                                 inode->i_op = &proc_netdir_inode_operations;
 209                                 break;
 210                         case PROC_SCSI:
 211                                 inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO;
 212                                 inode->i_nlink = 2;
 213                                 inode->i_op = &proc_scsi_inode_operations;
 214                                 break;
 215                         case PROC_KCORE:
 216                                 inode->i_mode = S_IFREG | S_IRUSR;
 217                                 inode->i_op = &proc_kcore_inode_operations;
 218                                 inode->i_size = high_memory + PAGE_SIZE;
 219                                 break;
 220 #ifdef CONFIG_PROFILE
 221                         case PROC_PROFILE:
 222                                 inode->i_mode = S_IFREG | S_IRUGO | S_IWUSR;
 223                                 inode->i_op = &proc_profile_inode_operations;
 224                                 inode->i_size = (1+prof_len) * sizeof(unsigned long);
 225                                 break;
 226 #endif
 227                         default:
 228                                 inode->i_mode = S_IFREG | S_IRUGO;
 229                                 inode->i_op = &proc_array_inode_operations;
 230                                 break;
 231                 }
 232                 return;
 233         }
 234         ino &= 0x0000ffff;
 235         if (ino == PROC_PID_INO || p->dumpable) {
 236                 inode->i_uid = p->euid;
 237                 inode->i_gid = p->egid;
 238         }
 239         switch (ino) {
 240                 case PROC_PID_INO:
 241                         inode->i_nlink = 4;
 242                         inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO;
 243                         inode->i_op = &proc_base_inode_operations;
 244                         return;
 245                 case PROC_PID_MEM:
 246                         inode->i_op = &proc_mem_inode_operations;
 247                         inode->i_mode = S_IFREG | S_IRUSR | S_IWUSR;
 248                         return;
 249                 case PROC_PID_CWD:
 250                 case PROC_PID_ROOT:
 251                 case PROC_PID_EXE:
 252                         inode->i_op = &proc_link_inode_operations;
 253                         inode->i_size = 64;
 254                         inode->i_mode = S_IFLNK | S_IRWXU;
 255                         return;
 256                 case PROC_PID_FD:
 257                         inode->i_mode = S_IFDIR | S_IRUSR | S_IXUSR;
 258                         inode->i_op = &proc_fd_inode_operations;
 259                         inode->i_nlink = 2;
 260                         return;
 261                 case PROC_PID_ENVIRON:
 262                         inode->i_mode = S_IFREG | S_IRUSR;
 263                         inode->i_op = &proc_array_inode_operations;
 264                         return;
 265                 case PROC_PID_CMDLINE:
 266                 case PROC_PID_STAT:
 267                 case PROC_PID_STATM:
 268                         inode->i_mode = S_IFREG | S_IRUGO;
 269                         inode->i_op = &proc_array_inode_operations;
 270                         return;
 271                 case PROC_PID_MAPS:
 272                         inode->i_mode = S_IFIFO | S_IRUGO;
 273                         inode->i_op = &proc_arraylong_inode_operations;
 274                         return;
 275         }
 276         switch (ino >> 8) {
 277                 case PROC_PID_FD_DIR:
 278                         ino &= 0xff;
 279                         if (ino >= NR_OPEN || !p->files->fd[ino])
 280                                 return;
 281                         inode->i_op = &proc_link_inode_operations;
 282                         inode->i_size = 64;
 283                         inode->i_mode = S_IFLNK;
 284                         if (p->files->fd[ino]->f_mode & 1)
 285                                 inode->i_mode |= S_IRUSR | S_IXUSR;
 286                         if (p->files->fd[ino]->f_mode & 2)
 287                                 inode->i_mode |= S_IWUSR | S_IXUSR;
 288                         return;
 289         }
 290         return;
 291 }
 292 
 293 void proc_write_inode(struct inode * inode)
     /*  */
 294 {
 295         inode->i_dirt=0;
 296 }
/* */
root/fs/proc/inode.c

DEFINITIONS
