dir-item.c

   1 #include <stdio.h>
   2 #include <stdlib.h>
   3 #include "kerncompat.h"
   4 #include "radix-tree.h"
   5 #include "ctree.h"
   6 #include "disk-io.h"
   7 #include "hash.h"
   8 #include "transaction.h"
   9
  10 static struct btrfs_dir_item *insert_with_overflow(struct
  11                                                    btrfs_trans_handle *trans,
  12                                                    struct btrfs_root *root,
  13                                                    struct btrfs_path *path,
  14                                                    struct btrfs_key *cpu_key,
  15                                                    u32 data_size)
  16 {
  17         int ret;
  18         char *ptr;
  19         struct btrfs_item *item;
  20         struct btrfs_leaf *leaf;
  21
  22         ret = btrfs_insert_empty_item(trans, root, path, cpu_key, data_size);
  23         if (ret == -EEXIST) {
  24                 ret = btrfs_extend_item(trans, root, path, data_size);
  25                 BUG_ON(ret > 0);
  26                 if (ret)
  27                         return NULL;
  28         }
  29         BUG_ON(ret > 0);
  30         leaf = &path->nodes[0]->leaf;
  31         item = leaf->items + path->slots[0];
  32         ptr = btrfs_item_ptr(leaf, path->slots[0], char);
  33         BUG_ON(data_size > btrfs_item_size(item));
  34         ptr += btrfs_item_size(item) - data_size;
  35         return (struct btrfs_dir_item *)ptr;
  36 }
  37
  38 int btrfs_insert_dir_item(struct btrfs_trans_handle *trans, struct btrfs_root
  39                           *root, char *name, int name_len, u64 dir,
  40                           struct btrfs_key *location, u8 type)
  41 {
  42         int ret = 0;
  43         struct btrfs_path path;
  44         struct btrfs_dir_item *dir_item;
  45         char *name_ptr;
  46         struct btrfs_key key;
  47         u32 data_size;
  48
  49         key.objectid = dir;
  50         key.flags = 0;
  51         btrfs_set_key_type(&key, BTRFS_DIR_ITEM_KEY);
  52         if (name_len == 1 && *name == '.')
  53                 key.offset = 1;
  54         else if (name_len == 2 && name[0] == '.' && name[1] == '.')
  55                 key.offset = 2;
  56         else
  57                 ret = btrfs_name_hash(name, name_len, &key.offset);
  58         BUG_ON(ret);
  59         btrfs_init_path(&path);
  60         data_size = sizeof(*dir_item) + name_len;
  61         dir_item = insert_with_overflow(trans, root, &path, &key, data_size);
  62         if (!dir_item) {
  63                 ret = -1;
  64                 goto out;
  65         }
  66         btrfs_cpu_key_to_disk(&dir_item->location, location);
  67         btrfs_set_dir_type(dir_item, type);
  68         btrfs_set_dir_flags(dir_item, 0);
  69         btrfs_set_dir_name_len(dir_item, name_len);
  70         name_ptr = (char *)(dir_item + 1);
  71         memcpy(name_ptr, name, name_len);
  72
  73         /* FIXME, use some real flag for selecting the extra index */
  74         if (root == root->fs_info->tree_root)
  75                 goto out;
  76
  77         btrfs_release_path(root, &path);
  78         btrfs_set_key_type(&key, BTRFS_DIR_INDEX_KEY);
  79         key.offset = location->objectid;
  80         dir_item = insert_with_overflow(trans, root, &path, &key, data_size);
  81         if (!dir_item) {
  82                 ret = -1;
  83                 goto out;
  84         }
  85         btrfs_cpu_key_to_disk(&dir_item->location, location);
  86         btrfs_set_dir_type(dir_item, type);
  87         btrfs_set_dir_flags(dir_item, 0);
  88         btrfs_set_dir_name_len(dir_item, name_len);
  89         name_ptr = (char *)(dir_item + 1);
  90         memcpy(name_ptr, name, name_len);
  91 out:
  92         btrfs_release_path(root, &path);
  93         return ret;
  94 }
  95
  96 int btrfs_lookup_dir_item(struct btrfs_trans_handle *trans, struct btrfs_root
  97                           *root, struct btrfs_path *path, u64 dir, char *name,
  98                           int name_len, int mod)
  99 {
 100         int ret;
 101         struct btrfs_key key;
 102         int ins_len = mod < 0 ? -1 : 0;
 103         int cow = mod != 0;
 104
 105         key.objectid = dir;
 106         key.flags = 0;
 107         btrfs_set_key_type(&key, BTRFS_DIR_ITEM_KEY);
 108         ret = btrfs_name_hash(name, name_len, &key.offset);
 109         BUG_ON(ret);
 110         ret = btrfs_search_slot(trans, root, &key, path, ins_len, cow);
 111         return ret;
 112 }
 113
 114 int btrfs_match_dir_item_name(struct btrfs_root *root,
 115                               struct btrfs_path *path, char
 116                               *name, int name_len)
 117 {
 118         struct btrfs_dir_item *dir_item;
 119         char *name_ptr;
 120
 121         dir_item = btrfs_item_ptr(&path->nodes[0]->leaf, path->slots[0],
 122                                   struct btrfs_dir_item);
 123         if (btrfs_dir_name_len(dir_item) != name_len)
 124                 return 0;
 125         name_ptr = (char *)(dir_item + 1);
 126         if (memcmp(name_ptr, name, name_len))
 127                 return 0;
 128         return 1;
 129 }