fs/reiser4/plugin/file/symlink.c

   1 /* Copyright 2002, 2003, 2005 by Hans Reiser, licensing governed by reiser4/README */
   2
   3 #include "../../inode.h"
   4
   5 #include <linux/types.h>
   6 #include <linux/fs.h>
   7
   8 /* file plugin methods specific for symlink files
   9    (SYMLINK_FILE_PLUGIN_ID) */
  10
  11 /* this is implementation of create_object method of file plugin for
  12    SYMLINK_FILE_PLUGIN_ID
  13  */
  14
  15 /**
  16  * reiser4_create_symlink - create_object of file plugin for SYMLINK_FILE_PLUGIN_ID
  17  * @symlink: inode of symlink object
  18  * @dir: inode of parent directory
  19  * @info:  parameters of new object
  20  *
  21  * Inserts stat data with symlink extension where into the tree.
  22  */
  23 int reiser4_create_symlink(struct inode *symlink,
  24                            struct inode *dir UNUSED_ARG,
  25                            reiser4_object_create_data *data /* info passed to us
  26                                                              * this is filled by
  27                                                              * reiser4() syscall
  28                                                              * in particular */)
  29 {
  30         int result;
  31
  32         assert("nikita-680", symlink != NULL);
  33         assert("nikita-681", S_ISLNK(symlink->i_mode));
  34         assert("nikita-685", reiser4_inode_get_flag(symlink, REISER4_NO_SD));
  35         assert("nikita-682", dir != NULL);
  36         assert("nikita-684", data != NULL);
  37         assert("nikita-686", data->id == SYMLINK_FILE_PLUGIN_ID);
  38
  39         /*
  40          * stat data of symlink has symlink extension in which we store
  41          * symlink content, that is, path symlink is pointing to.
  42          */
  43         reiser4_inode_data(symlink)->extmask |= (1 << SYMLINK_STAT);
  44
  45         assert("vs-838", symlink->i_private == NULL);
  46         symlink->i_private = (void *)data->name;
  47
  48         assert("vs-843", symlink->i_size == 0);
  49         INODE_SET_FIELD(symlink, i_size, strlen(data->name));
  50
  51         /* insert stat data appended with data->name */
  52         result = inode_file_plugin(symlink)->write_sd_by_inode(symlink);
  53         if (result) {
  54                 /* FIXME-VS: Make sure that symlink->i_private is not attached
  55                    to kmalloced data */
  56                 INODE_SET_FIELD(symlink, i_size, 0);
  57         } else {
  58                 assert("vs-849", symlink->i_private
  59                        && reiser4_inode_get_flag(symlink,
  60                                                  REISER4_GENERIC_PTR_USED));
  61                 assert("vs-850",
  62                        !memcmp((char *)symlink->i_private, data->name,
  63                                (size_t) symlink->i_size + 1));
  64         }
  65         return result;
  66 }
  67
  68 /* this is implementation of destroy_inode method of file plugin for
  69    SYMLINK_FILE_PLUGIN_ID
  70  */
  71 void destroy_inode_symlink(struct inode *inode)
  72 {
  73         assert("edward-799",
  74                inode_file_plugin(inode) ==
  75                file_plugin_by_id(SYMLINK_FILE_PLUGIN_ID));
  76         assert("edward-800", !is_bad_inode(inode) && is_inode_loaded(inode));
  77         assert("edward-801", reiser4_inode_get_flag(inode,
  78                                                     REISER4_GENERIC_PTR_USED));
  79         assert("vs-839", S_ISLNK(inode->i_mode));
  80
  81         kfree(inode->i_private);
  82         inode->i_private = NULL;
  83         reiser4_inode_clr_flag(inode, REISER4_GENERIC_PTR_USED);
  84 }
  85
  86 /*
  87   Local variables:
  88   c-indentation-style: "K&R"
  89   mode-name: "LC"
  90   c-basic-offset: 8
  91   tab-width: 8
  92   fill-column: 80
  93   scroll-step: 1
  94   End:
  95 */