fs/proc/inode.c

/* */
This source file includes following definitions.
proc_put_inode
proc_put_super
parse_options
proc_get_inode
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 static void proc_put_inode(struct inode *inode)
     /*  */
  21 {
  22         if (inode->i_nlink)
  23                 return;
  24         inode->i_size = 0;
  25 }
  26 
  27 static void proc_put_super(struct super_block *sb)
     /*  */
  28 {
  29         lock_super(sb);
  30         sb->s_dev = 0;
  31         unlock_super(sb);
  32 }
  33 
  34 static struct super_operations proc_sops = { 
  35         proc_read_inode,
  36         NULL,
  37         proc_write_inode,
  38         proc_put_inode,
  39         proc_put_super,
  40         NULL,
  41         proc_statfs,
  42         NULL
  43 };
  44 
  45 
  46 static int parse_options(char *options,uid_t *uid,gid_t *gid)
     /*  */
  47 {
  48         char *this_char,*value;
  49 
  50         *uid = current->uid;
  51         *gid = current->gid;
  52         if (!options) return 1;
  53         for (this_char = strtok(options,","); this_char; this_char = strtok(NULL,",")) {
  54                 if ((value = strchr(this_char,'=')) != NULL)
  55                         *value++ = 0;
  56                 if (!strcmp(this_char,"uid")) {
  57                         if (!value || !*value)
  58                                 return 0;
  59                         *uid = simple_strtoul(value,&value,0);
  60                         if (*value)
  61                                 return 0;
  62                 }
  63                 else if (!strcmp(this_char,"gid")) {
  64                         if (!value || !*value)
  65                                 return 0;
  66                         *gid = simple_strtoul(value,&value,0);
  67                         if (*value)
  68                                 return 0;
  69                 }
  70                 else return 0;
  71         }
  72         return 1;
  73 }
  74 
  75 struct inode * proc_get_inode(struct super_block * s, int ino, struct proc_dir_entry * de)
     /*  */
  76 {
  77         struct inode * inode = iget(s, ino);
  78         if (inode) {
  79                 inode->u.generic_ip = (void *) de;
  80                 if (de) {
  81                         if (de->mode) {
  82                                 inode->i_mode = de->mode;
  83                                 inode->i_uid = de->uid;
  84                                 inode->i_gid = de->gid;
  85                         }
  86                         if (de->size)
  87                                 inode->i_size = de->size;
  88                         if (de->ops)
  89                                 inode->i_op = de->ops;
  90                         if (de->nlink)
  91                                 inode->i_nlink = de->nlink;
  92                         if (de->fill_inode)
  93                                 de->fill_inode(inode);
  94                 }
  95         }
  96         return inode;
  97 }                       
  98 
  99 struct super_block *proc_read_super(struct super_block *s,void *data, 
     /*  */
 100                                     int silent)
 101 {
 102         proc_root_init();
 103         lock_super(s);
 104         s->s_blocksize = 1024;
 105         s->s_blocksize_bits = 10;
 106         s->s_magic = PROC_SUPER_MAGIC;
 107         s->s_op = &proc_sops;
 108         unlock_super(s);
 109         if (!(s->s_mounted = proc_get_inode(s, PROC_ROOT_INO, &proc_root))) {
 110                 s->s_dev = 0;
 111                 printk("get root inode failed\n");
 112                 return NULL;
 113         }
 114         parse_options(data, &s->s_mounted->i_uid, &s->s_mounted->i_gid);
 115         return s;
 116 }
 117 
 118 void proc_statfs(struct super_block *sb, struct statfs *buf, int bufsiz)
     /*  */
 119 {
 120         struct statfs tmp;
 121 
 122         tmp.f_type = PROC_SUPER_MAGIC;
 123         tmp.f_bsize = PAGE_SIZE/sizeof(long);
 124         tmp.f_blocks = 0;
 125         tmp.f_bfree = 0;
 126         tmp.f_bavail = 0;
 127         tmp.f_files = 0;
 128         tmp.f_ffree = 0;
 129         tmp.f_namelen = NAME_MAX;
 130         memcpy_tofs(buf, &tmp, bufsiz);
 131 }
 132 
 133 void proc_read_inode(struct inode * inode)
     /*  */
 134 {
 135         unsigned long ino, pid;
 136         struct task_struct * p;
 137         int i;
 138         
 139         inode->i_op = NULL;
 140         inode->i_mode = 0;
 141         inode->i_uid = 0;
 142         inode->i_gid = 0;
 143         inode->i_nlink = 1;
 144         inode->i_size = 0;
 145         inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
 146         inode->i_blocks = 0;
 147         inode->i_blksize = 1024;
 148         ino = inode->i_ino;
 149         pid = ino >> 16;
 150         p = task[0];
 151         for (i = 0; i < NR_TASKS ; i++)
 152                 if ((p = task[i]) && (p->pid == pid))
 153                         break;
 154         if (!p || i >= NR_TASKS)
 155                 return;
 156         if (ino == PROC_ROOT_INO) {
 157                 inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO;
 158                 inode->i_nlink = 2;
 159                 for (i = 1 ; i < NR_TASKS ; i++)
 160                         if (task[i])
 161                                 inode->i_nlink++;
 162                 return;
 163         }
 164 
 165         if (ino == PROC_SCSI_SCSI) {
 166                 inode->i_mode = S_IFREG | S_IRUGO | S_IWUSR;
 167                 inode->i_op = &proc_scsi_inode_operations;
 168                 return;
 169         }
 170         /*
 171          * Special hook used when scsi is not present.
 172          */
 173         if (ino == PROC_SCSI_NOT_PRESENT) {
 174                 inode->i_mode = S_IFREG | S_IRUGO | S_IXUGO;
 175                 inode->i_op = &proc_scsi_inode_operations;
 176                 return;
 177         }
 178 
 179         /* files within /proc/scsi */
 180         if ((ino > PROC_SCSI_SCSI) && (ino < PROC_SCSI_FILE)) {
 181                 inode->i_nlink = 2;
 182                 inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO;
 183                 inode->i_op = &proc_scsi_inode_operations;
 184                 return;
 185         }
 186 
 187         /* files within /proc/scsi/<driver>/  */
 188         if ((ino >= PROC_SCSI_FILE) && (ino <= PROC_SCSI_LAST)) {
 189                 inode->i_mode = S_IFREG | S_IRUGO | S_IWUSR;
 190                 inode->i_op = &proc_scsi_inode_operations;
 191                 return;
 192         }
 193 
 194         if (!pid) {
 195                 switch (ino) {
 196                         case PROC_KMSG:
 197                                 inode->i_mode = S_IFREG | S_IRUSR;
 198                                 inode->i_op = &proc_kmsg_inode_operations;
 199                                 break;
 200                         case PROC_NET:
 201                                 inode->i_nlink = 2;
 202                                 break;
 203                         case PROC_SCSI:
 204                                 inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO;
 205                                 inode->i_nlink = 2;
 206                                 inode->i_op = &proc_scsi_inode_operations;
 207                                 break;
 208                         case PROC_KCORE:
 209                                 inode->i_mode = S_IFREG | S_IRUSR;
 210                                 inode->i_op = &proc_kcore_inode_operations;
 211                                 inode->i_size = (MAP_NR(high_memory) << PAGE_SHIFT) + PAGE_SIZE;
 212                                 break;
 213                         case PROC_PROFILE:
 214                                 inode->i_mode = S_IFREG | S_IRUGO | S_IWUSR;
 215                                 inode->i_op = &proc_profile_inode_operations;
 216                                 inode->i_size = (1+prof_len) * sizeof(unsigned long);
 217                                 break;
 218                         default:
 219                                 inode->i_mode = S_IFREG | S_IRUGO;
 220                                 inode->i_op = &proc_array_inode_operations;
 221                                 break;
 222                 }
 223                 return;
 224         }
 225         ino &= 0x0000ffff;
 226         if (ino == PROC_PID_INO || p->dumpable) {
 227                 inode->i_uid = p->euid;
 228                 inode->i_gid = p->egid;
 229         }
 230         switch (ino) {
 231                 case PROC_PID_INO:
 232                         inode->i_nlink = 4;
 233                         return;
 234                 case PROC_PID_MEM:
 235                         inode->i_op = &proc_mem_inode_operations;
 236                         inode->i_mode = S_IFREG | S_IRUSR | S_IWUSR;
 237                         return;
 238                 case PROC_PID_CWD:
 239                 case PROC_PID_ROOT:
 240                 case PROC_PID_EXE:
 241                         inode->i_op = &proc_link_inode_operations;
 242                         inode->i_size = 64;
 243                         inode->i_mode = S_IFLNK | S_IRWXU;
 244                         return;
 245                 case PROC_PID_FD:
 246                         inode->i_mode = S_IFDIR | S_IRUSR | S_IXUSR;
 247                         inode->i_op = &proc_fd_inode_operations;
 248                         inode->i_nlink = 2;
 249                         return;
 250                 case PROC_PID_ENVIRON:
 251                         inode->i_mode = S_IFREG | S_IRUSR;
 252                         inode->i_op = &proc_array_inode_operations;
 253                         return;
 254                 case PROC_PID_CMDLINE:
 255                 case PROC_PID_STAT:
 256                 case PROC_PID_STATM:
 257                         inode->i_mode = S_IFREG | S_IRUGO;
 258                         inode->i_op = &proc_array_inode_operations;
 259                         return;
 260                 case PROC_PID_MAPS:
 261                         inode->i_mode = S_IFIFO | S_IRUGO;
 262                         inode->i_op = &proc_arraylong_inode_operations;
 263                         return;
 264         }
 265         switch (ino >> 8) {
 266                 case PROC_PID_FD_DIR:
 267                         ino &= 0xff;
 268                         if (ino >= NR_OPEN || !p->files->fd[ino])
 269                                 return;
 270                         inode->i_op = &proc_link_inode_operations;
 271                         inode->i_size = 64;
 272                         inode->i_mode = S_IFLNK;
 273                         if (p->files->fd[ino]->f_mode & 1)
 274                                 inode->i_mode |= S_IRUSR | S_IXUSR;
 275                         if (p->files->fd[ino]->f_mode & 2)
 276                                 inode->i_mode |= S_IWUSR | S_IXUSR;
 277                         return;
 278         }
 279         return;
 280 }
 281 
 282 void proc_write_inode(struct inode * inode)
     /*  */
 283 {
 284         inode->i_dirt=0;
 285 }
/* */
root/fs/proc/inode.c

DEFINITIONS
