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 extern unsigned long prof_len;
  21 
  22 static void proc_put_inode(struct inode *inode)
     /*  */
  23 {
  24         if (inode->i_nlink)
  25                 return;
  26         inode->i_size = 0;
  27 }
  28 
  29 static 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 struct inode * proc_get_inode(struct super_block * s, int ino, struct proc_dir_entry * de)
     /*  */
  78 {
  79         struct inode * inode = iget(s, ino);
  80         if (inode) {
  81                 inode->u.generic_ip = (void *) de;
  82                 if (de) {
  83                         if (de->mode) {
  84                                 inode->i_mode = de->mode;
  85                                 inode->i_uid = de->uid;
  86                                 inode->i_gid = de->gid;
  87                         }
  88                         if (de->size)
  89                                 inode->i_size = de->size;
  90                         if (de->ops)
  91                                 inode->i_op = de->ops;
  92                         if (de->nlink)
  93                                 inode->i_nlink = de->nlink;
  94                         if (de->fill_inode)
  95                                 de->fill_inode(inode);
  96                 }
  97         }
  98         return inode;
  99 }                       
 100 
 101 struct super_block *proc_read_super(struct super_block *s,void *data, 
     /*  */
 102                                     int silent)
 103 {
 104         proc_root_init();
 105         lock_super(s);
 106         s->s_blocksize = 1024;
 107         s->s_blocksize_bits = 10;
 108         s->s_magic = PROC_SUPER_MAGIC;
 109         s->s_op = &proc_sops;
 110         unlock_super(s);
 111         if (!(s->s_mounted = proc_get_inode(s, PROC_ROOT_INO, &proc_root))) {
 112                 s->s_dev = 0;
 113                 printk("get root inode failed\n");
 114                 return NULL;
 115         }
 116         parse_options(data, &s->s_mounted->i_uid, &s->s_mounted->i_gid);
 117         return s;
 118 }
 119 
 120 void proc_statfs(struct super_block *sb, struct statfs *buf, int bufsiz)
     /*  */
 121 {
 122         struct statfs tmp;
 123 
 124         tmp.f_type = PROC_SUPER_MAGIC;
 125         tmp.f_bsize = PAGE_SIZE/sizeof(long);
 126         tmp.f_blocks = 0;
 127         tmp.f_bfree = 0;
 128         tmp.f_bavail = 0;
 129         tmp.f_files = 0;
 130         tmp.f_ffree = 0;
 131         tmp.f_namelen = NAME_MAX;
 132         memcpy_tofs(buf, &tmp, bufsiz);
 133 }
 134 
 135 void proc_read_inode(struct inode * inode)
     /*  */
 136 {
 137         unsigned long ino, pid;
 138         struct task_struct * p;
 139         int i;
 140         
 141         inode->i_op = NULL;
 142         inode->i_mode = 0;
 143         inode->i_uid = 0;
 144         inode->i_gid = 0;
 145         inode->i_nlink = 1;
 146         inode->i_size = 0;
 147         inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
 148         inode->i_blocks = 0;
 149         inode->i_blksize = 1024;
 150         ino = inode->i_ino;
 151         pid = ino >> 16;
 152         p = task[0];
 153         for (i = 0; i < NR_TASKS ; i++)
 154                 if ((p = task[i]) && (p->pid == pid))
 155                         break;
 156         if (!p || i >= NR_TASKS)
 157                 return;
 158         if (ino == PROC_ROOT_INO) {
 159                 inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO;
 160                 inode->i_nlink = 2;
 161                 for (i = 1 ; i < NR_TASKS ; i++)
 162                         if (task[i])
 163                                 inode->i_nlink++;
 164                 return;
 165         }
 166 
 167         if (ino == PROC_SCSI_SCSI) {
 168                 inode->i_mode = S_IFREG | S_IRUGO | S_IWUSR;
 169                 inode->i_op = &proc_scsi_inode_operations;
 170                 return;
 171         }
 172         /*
 173          * Special hook used when scsi is not present.
 174          */
 175         if (ino == PROC_SCSI_NOT_PRESENT) {
 176                 inode->i_mode = S_IFREG | S_IRUGO | S_IXUGO;
 177                 inode->i_op = &proc_scsi_inode_operations;
 178                 return;
 179         }
 180 
 181         /* files within /proc/scsi */
 182         if ((ino > PROC_SCSI_SCSI) && (ino < PROC_SCSI_FILE)) {
 183                 inode->i_nlink = 2;
 184                 inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO;
 185                 inode->i_op = &proc_scsi_inode_operations;
 186                 return;
 187         }
 188 
 189         /* files within /proc/scsi/<driver>/  */
 190         if ((ino >= PROC_SCSI_FILE) && (ino <= PROC_SCSI_LAST)) {
 191                 inode->i_mode = S_IFREG | S_IRUGO | S_IWUSR;
 192                 inode->i_op = &proc_scsi_inode_operations;
 193                 return;
 194         }
 195 
 196         if (!pid) {
 197                 switch (ino) {
 198                         case PROC_KMSG:
 199                                 inode->i_mode = S_IFREG | S_IRUSR;
 200                                 inode->i_op = &proc_kmsg_inode_operations;
 201                                 break;
 202                         case PROC_NET:
 203                                 inode->i_nlink = 2;
 204                                 break;
 205                         case PROC_SCSI:
 206                                 inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO;
 207                                 inode->i_nlink = 2;
 208                                 inode->i_op = &proc_scsi_inode_operations;
 209                                 break;
 210                         case PROC_KCORE:
 211                                 inode->i_mode = S_IFREG | S_IRUSR;
 212                                 inode->i_op = &proc_kcore_inode_operations;
 213                                 inode->i_size = high_memory + PAGE_SIZE;
 214                                 break;
 215 #ifdef CONFIG_PROFILE
 216                         case PROC_PROFILE:
 217                                 inode->i_mode = S_IFREG | S_IRUGO | S_IWUSR;
 218                                 inode->i_op = &proc_profile_inode_operations;
 219                                 inode->i_size = (1+prof_len) * sizeof(unsigned long);
 220                                 break;
 221 #endif
 222                         default:
 223                                 inode->i_mode = S_IFREG | S_IRUGO;
 224                                 inode->i_op = &proc_array_inode_operations;
 225                                 break;
 226                 }
 227                 return;
 228         }
 229         ino &= 0x0000ffff;
 230         if (ino == PROC_PID_INO || p->dumpable) {
 231                 inode->i_uid = p->euid;
 232                 inode->i_gid = p->egid;
 233         }
 234         switch (ino) {
 235                 case PROC_PID_INO:
 236                         inode->i_nlink = 4;
 237                         return;
 238                 case PROC_PID_MEM:
 239                         inode->i_op = &proc_mem_inode_operations;
 240                         inode->i_mode = S_IFREG | S_IRUSR | S_IWUSR;
 241                         return;
 242                 case PROC_PID_CWD:
 243                 case PROC_PID_ROOT:
 244                 case PROC_PID_EXE:
 245                         inode->i_op = &proc_link_inode_operations;
 246                         inode->i_size = 64;
 247                         inode->i_mode = S_IFLNK | S_IRWXU;
 248                         return;
 249                 case PROC_PID_FD:
 250                         inode->i_mode = S_IFDIR | S_IRUSR | S_IXUSR;
 251                         inode->i_op = &proc_fd_inode_operations;
 252                         inode->i_nlink = 2;
 253                         return;
 254                 case PROC_PID_ENVIRON:
 255                         inode->i_mode = S_IFREG | S_IRUSR;
 256                         inode->i_op = &proc_array_inode_operations;
 257                         return;
 258                 case PROC_PID_CMDLINE:
 259                 case PROC_PID_STAT:
 260                 case PROC_PID_STATM:
 261                         inode->i_mode = S_IFREG | S_IRUGO;
 262                         inode->i_op = &proc_array_inode_operations;
 263                         return;
 264                 case PROC_PID_MAPS:
 265                         inode->i_mode = S_IFIFO | S_IRUGO;
 266                         inode->i_op = &proc_arraylong_inode_operations;
 267                         return;
 268         }
 269         switch (ino >> 8) {
 270                 case PROC_PID_FD_DIR:
 271                         ino &= 0xff;
 272                         if (ino >= NR_OPEN || !p->files->fd[ino])
 273                                 return;
 274                         inode->i_op = &proc_link_inode_operations;
 275                         inode->i_size = 64;
 276                         inode->i_mode = S_IFLNK;
 277                         if (p->files->fd[ino]->f_mode & 1)
 278                                 inode->i_mode |= S_IRUSR | S_IXUSR;
 279                         if (p->files->fd[ino]->f_mode & 2)
 280                                 inode->i_mode |= S_IWUSR | S_IXUSR;
 281                         return;
 282         }
 283         return;
 284 }
 285 
 286 void proc_write_inode(struct inode * inode)
     /*  */
 287 {
 288         inode->i_dirt=0;
 289 }
/* */
root/fs/proc/inode.c

DEFINITIONS
