]> wimlib.net Git - wimlib/blobdiff - src/hardlink.c
fix_true_inode(): Fix bug
[wimlib] / src / hardlink.c
index ba4f2e165ce45d0b87a56572b638818fe6a72203..93030d8f7e10e6b89874a089c28da575c63e850d 100644 (file)
@@ -1,19 +1,27 @@
+/*
+ * hardlink.c
+ *
+ * Code to deal with hard links in WIMs.  Essentially, the WIM dentries are put
+ * into a hash table indexed by the inode ID field, then for each hard
+ * inode, a linked list is made to connect the dentries.
+ */
+
 /*
  * Copyright (C) 2012 Eric Biggers
  *
  * This file is part of wimlib, a library for working with WIM files.
  *
  * wimlib is free software; you can redistribute it and/or modify it under the
- * terms of the GNU Lesser General Public License as published by the Free
- * Software Foundation; either version 2.1 of the License, or (at your option)
+ * terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 3 of the License, or (at your option)
  * any later version.
  *
  * wimlib is distributed in the hope that it will be useful, but WITHOUT ANY
  * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
- * A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
+ * A PARTICULAR PURPOSE. See the GNU General Public License for more
  * details.
  *
- * You should have received a copy of the GNU Lesser General Public License
+ * You should have received a copy of the GNU General Public License
  * along with wimlib; if not, see http://www.gnu.org/licenses/.
  */
 
 #include "list.h"
 #include "lookup_table.h"
 
-/* Hard link group; it's identified by its hard link group ID and consists of a
- * circularly linked list of dentries. */
-struct link_group {
-       u64 link_group_id;
-       struct link_group *next;
-       struct list_head *dentry_list;
-};
+/*                             NULL        NULL
+ *                              ^           ^
+ *         dentry               |           |
+ *        /     \          -----------  -----------
+ *        |      dentry<---|  struct  | |  struct  |---> dentry
+ *        \     /          |  inode   | |  inode   |
+ *         dentry          ------------ ------------
+ *                              ^           ^
+ *                              |           |
+ *                              |           |                   dentry
+ *                         -----------  -----------            /      \
+ *               dentry<---|  struct  | |  struct  |---> dentry        dentry
+ *              /          |  inode   | |  inode   |           \      /
+ *         dentry          ------------ ------------            dentry
+ *                              ^           ^
+ *                              |           |
+ *                            -----------------
+ *        inode_table->array  | idx 0 | idx 1 |
+ *                            -----------------
+ */
 
-/* Hash table to find hard link groups, identified by their hard link group ID.
+/* Hash table to find inodes, identified by their inode ID.
  * */
-struct link_group_table {
-       struct link_group **array;
+struct inode_table {
+       /* Fields for the hash table */
+       struct hlist_head *array;
        u64 num_entries;
        u64 capacity;
-       struct link_group *singles;
+
+       /*
+        * Linked list of "extra" inodes.  These may be:
+        *
+        * - inodes with link count 1, which are all allowed to have 0 for their
+        *   inode number, meaning we cannot insert them into the hash table
+        *   before calling assign_inode_numbers().
+         *
+        * - Groups we create ourselves by splitting a nominal inode due to
+        *   inconsistencies in the dentries.  These inodes will share a inode
+        *   ID with some other inode until assign_inode_numbers() is called.
+        */
+       struct hlist_head extra_inodes;
 };
 
-/* Returns pointer to a new link group table having the specified capacity */
-struct link_group_table *new_link_group_table(u64 capacity)
+static inline void destroy_inode_table(struct inode_table *table)
+{
+       FREE(table->array);
+}
+
+static int init_inode_table(struct inode_table *table, size_t capacity)
 {
-       struct link_group_table *table;
-       struct link_group **array;
-
-       table = MALLOC(sizeof(struct link_group_table));
-       if (!table)
-               goto err;
-       array = CALLOC(capacity, sizeof(array[0]));
-       if (!array) {
-               FREE(table);
-               goto err;
+       table->array = CALLOC(capacity, sizeof(table->array[0]));
+       if (!table->array) {
+               ERROR("Cannot initalize inode table: out of memory");
+               return WIMLIB_ERR_NOMEM;
        }
-       table->num_entries = 0;
-       table->capacity = capacity;
-       table->array = array;
-       table->singles = NULL;
-       return table;
-err:
-       ERROR("Failed to allocate memory for link group table with capacity %zu",
-             capacity);
-       return NULL;
+       table->num_entries  = 0;
+       table->capacity     = capacity;
+       INIT_HLIST_HEAD(&table->extra_inodes);
+       return 0;
 }
 
-/* 
- * Insert a dentry into the hard link group table based on its hard link group
+static inline size_t inode_link_count(const struct inode *inode)
+{
+       const struct list_head *cur;
+       size_t size = 0;
+       list_for_each(cur, &inode->dentry_list)
+               size++;
+       return size;
+}
+
+/*
+ * Insert a dentry into the inode table based on its inode
  * ID.
  *
- * If there is already a dentry in the table having the same hard link group ID,
- * we link the dentries together in a circular list.
+ * If there is already a dentry in the table having the same inode ID,
+ * and the inode ID is not 0, the dentry is added to the circular
+ * linked list for that inode.
  *
- * If the hard link group ID is 0, this indicates a dentry that's in a hard link
- * group by itself (has a link count of 1).  We can't insert it into the hash
- * table itself because we don't know what hard link group IDs are available to
+ * If the inode ID is 0, this indicates a dentry that's in a hard link
+ * inode by itself (has a link count of 1).  We can't insert it into the hash
+ * table itself because we don't know what inode numbers are available to
  * give it (this could be kept track of but would be more difficult).  Instead
- * we keep a linked list of the single dentries, and assign them hard link group
- * IDs later.
+ * we keep a linked list of the single dentries, and assign them inode
+ * numbers later.
  */
-int link_group_table_insert(struct dentry *dentry, void *__table)
+static int inode_table_insert(struct dentry *dentry, void *__table)
 {
-       struct link_group_table *table = __table;
-       size_t pos;
-       struct link_group *group;
-
-       if (dentry->hard_link == 0) {
-               /* Single group--- Add to the singles list (we can't put it in
-                * the table itself because all the singles have a link group ID
-                * of 0) */
-               group = MALLOC(sizeof(struct link_group));
-               if (!group)
-                       return WIMLIB_ERR_NOMEM;
-               group->link_group_id = 0;
-               group->next          = table->singles;
-               table->singles       = group;
-               INIT_LIST_HEAD(&dentry->link_group_list);
-               group->dentry_list = &dentry->link_group_list;
+       struct inode_table *table = __table;
+       struct inode *d_inode = dentry->d_inode;
+
+       if (d_inode->ino == 0) {
+               /* Single inode--- Add to the list of extra inodes (we can't put
+                * it in the table itself because all the singles have a link
+                * inode ID of 0) */
+               hlist_add_head(&d_inode->hlist, &table->extra_inodes);
+
+               wimlib_assert(d_inode->dentry_list.next == &dentry->inode_dentry_list);
+               wimlib_assert(d_inode->dentry_list.prev == &dentry->inode_dentry_list);
+               wimlib_assert(d_inode->link_count == 1);
        } else {
-               /* Hard link group that may should multiple dentries (the code
-                * will work even if the group actually contains only 1 dentry
+               /* Inode that may have multiple corresponding dentries (the code
+                * will work even if the inode actually contains only 1 dentry
                 * though) */
 
-               /* Try adding to existing hard link group */
-               pos = dentry->hard_link % table->capacity;
-               group = table->array[pos];
-               while (group) {
-                       if (group->link_group_id == dentry->hard_link) {
-                               list_add(&dentry->link_group_list,
-                                        group->dentry_list);
+               size_t pos;
+               struct inode *inode;
+               struct hlist_node *cur;
+
+               /* Try adding to existing inode */
+               pos = d_inode->ino % table->capacity;
+               hlist_for_each_entry(inode, cur, &table->array[pos], hlist) {
+                       if (inode->ino == d_inode->ino) {
+                               inode_add_dentry(dentry, inode);
+                               inode->link_count++;
                                return 0;
                        }
-                       group = group->next;
                }
 
-               /* Add new hard link group to the table */
+               /* Add new inode to the table */
+               hlist_add_head(&d_inode->hlist, &table->array[pos]);
 
-               group = MALLOC(sizeof(struct link_group));
-               if (!group)
-                       return WIMLIB_ERR_NOMEM;
-               group->link_group_id   = dentry->hard_link;
-               group->next            = table->array[pos];
-               INIT_LIST_HEAD(&dentry->link_group_list);
-               group->dentry_list = &dentry->link_group_list;
-               table->array[pos]      = group;
+               wimlib_assert(d_inode->dentry_list.next == &dentry->inode_dentry_list);
+               wimlib_assert(d_inode->dentry_list.prev == &dentry->inode_dentry_list);
+               wimlib_assert(d_inode->link_count == 1);
 
                /* XXX Make the table grow when too many entries have been
                 * inserted. */
@@ -131,201 +162,316 @@ int link_group_table_insert(struct dentry *dentry, void *__table)
        return 0;
 }
 
-/* Frees a link group table. */
-void free_link_group_table(struct link_group_table *table)
+/* Assign the inode numbers to dentries in a inode table, and return the
+ * next available inode ID. */
+u64 assign_inode_numbers(struct hlist_head *inode_list)
 {
-       struct link_group *single, *next;
-
-       if (!table)
-               return;
-       if (table->array) {
-               for (u64 i = 0; i < table->capacity; i++) {
-                       struct link_group *group = table->array[i];
-                       struct link_group *next;
-                       while (group) {
-                               next = group->next;
-                               FREE(group);
-                               group = next;
-                       }
-               }
-               FREE(table->array);
-       }
-       single = table->singles;
-       while (single) {
-               next = single->next;
-               FREE(single);
-               single = next;
+       DEBUG("Assigning inode numbers");
+       struct inode *inode;
+       struct hlist_node *cur;
+       u64 cur_ino = 1;
+       hlist_for_each_entry(inode, cur, inode_list, hlist) {
+               inode->ino = cur_ino;
+               cur_ino++;
        }
-
-       FREE(table);
+       return cur_ino;
 }
 
-/* Assign the link group IDs to dentries in a link group table, and return the
- * next available link group ID. */
-u64 assign_link_groups(struct link_group_table *table)
-{
-       DEBUG("Assigning link groups");
 
-       /* Assign consecutive link group IDs to each link group in the hash
-        * table */
-       u64 id = 1;
-       for (u64 i = 0; i < table->capacity; i++) {
-               struct link_group *group = table->array[i];
-               struct link_group *next_group;
-               struct dentry *dentry;
-               struct list_head *cur;
-               while (group) {
-                       cur = group->dentry_list;
-                       do {
-                               dentry = container_of(cur,
-                                                     struct dentry,
-                                                     link_group_list);
-                               dentry->hard_link = id;
-                               cur = cur->next;
-                       } while (cur != group->dentry_list);
-                       id++;
-                       group = group->next;
-               }
-       }
-       /* Assign link group IDs to the link groups that previously had link
-        * group IDs of 0, and insert them into the hash table */
-       struct link_group *single = table->singles;
-       while (single) {
-               struct dentry *dentry;
-               struct link_group *next_single;
-               size_t pos;
+static void print_inode_dentries(const struct inode *inode)
+{
+       struct dentry *dentry;
+       inode_for_each_dentry(dentry, inode)
+               printf("`%s'\n", dentry->full_path_utf8);
+}
 
-               next_single = single->next;
+static void inconsistent_inode(const struct inode *inode)
+{
+       ERROR("An inconsistent hard link group that cannot be corrected has "
+             "been detected");
+       ERROR("The dentries are located at the following paths:");
+#ifdef ENABLE_ERROR_MESSAGES
+       print_inode_dentries(inode);
+#endif
+}
 
-               dentry = container_of(single->dentry_list, struct dentry,
-                                     link_group_list);
-               dentry->hard_link = id;
+static bool ref_inodes_consistent(const struct inode * restrict ref_inode_1,
+                                 const struct inode * restrict ref_inode_2)
+{
+       wimlib_assert(ref_inode_1 != ref_inode_2);
 
-               pos = id % table->capacity;
-               single->next = table->array[pos];
-               table->array[pos] = single;
+       if (ref_inode_1->num_ads != ref_inode_2->num_ads)
+               return false;
+       if (ref_inode_1->security_id != ref_inode_2->security_id
+           || ref_inode_1->attributes != ref_inode_2->attributes)
+               return false;
+       for (unsigned i = 0; i <= ref_inode_1->num_ads; i++) {
+               const u8 *ref_1_hash, *ref_2_hash;
+               ref_1_hash = inode_stream_hash(ref_inode_1, i);
+               ref_2_hash = inode_stream_hash(ref_inode_2, i);
+               if (!hashes_equal(ref_1_hash, ref_2_hash))
+                       return false;
+               if (i && !ads_entries_have_same_name(&ref_inode_1->ads_entries[i - 1],
+                                                    &ref_inode_2->ads_entries[i - 1]))
+                       return false;
 
-               single = next_single;
-               id++;
        }
-       table->singles = NULL;
-       return id;
+       return true;
 }
 
-static bool dentries_have_same_ads(const struct dentry *d1,
-                                  const struct dentry *d2)
+static bool inodes_consistent(const struct inode * restrict ref_inode,
+                             const struct inode * restrict inode)
 {
-       /* Verify stream names and hashes are the same */
-       for (u16 i = 0; i < d1->num_ads; i++) {
-               if (strcmp(d1->ads_entries[i].stream_name_utf8,
-                          d2->ads_entries[i].stream_name_utf8) != 0)
+       wimlib_assert(ref_inode != inode);
+
+       if (ref_inode->num_ads != inode->num_ads &&
+           inode->num_ads != 0)
+               return false;
+       if (ref_inode->security_id != inode->security_id
+           || ref_inode->attributes != inode->attributes)
+               return false;
+       for (unsigned i = 0; i <= min(ref_inode->num_ads, inode->num_ads); i++) {
+               const u8 *ref_hash, *hash;
+               ref_hash = inode_stream_hash(ref_inode, i);
+               hash = inode_stream_hash(inode, i);
+               if (!hashes_equal(ref_hash, hash) && !is_zero_hash(hash))
                        return false;
-               if (memcmp(d1->ads_entries[i].hash,
-                          d2->ads_entries[i].hash,
-                          WIM_HASH_SIZE) != 0)
+               if (i && !ads_entries_have_same_name(&ref_inode->ads_entries[i - 1],
+                                                    &inode->ads_entries[i - 1]))
                        return false;
        }
        return true;
 }
 
-/* Share the alternate stream entries between hard-linked dentries. */
-static int share_dentry_ads(struct dentry *owner, struct dentry *user)
+/* Fix up a "true" inode and check for inconsistencies */
+static int fix_true_inode(struct inode *inode, struct hlist_head *inode_list)
 {
-       const char *mismatch_type;
-       wimlib_assert(owner->num_ads == 0 ||
-                     owner->ads_entries != user->ads_entries);
-       if (owner->attributes != user->attributes) {
-               mismatch_type = "attributes";
-               goto mismatch;
-       }
-       if (owner->attributes & FILE_ATTRIBUTE_DIRECTORY) {
-               WARNING("`%s' is hard-linked to `%s', which is a directory ",
-                       user->full_path_utf8, owner->full_path_utf8);
-               return WIMLIB_ERR_INVALID_DENTRY;
-       }
-       if (owner->security_id != user->security_id) {
-               mismatch_type = "security ID";
-               goto mismatch;
-       }
-       if (memcmp(owner->hash, user->hash, WIM_HASH_SIZE) != 0) {
-               mismatch_type = "main file resource";
-               goto mismatch;
+       struct dentry *dentry;
+       struct dentry *ref_dentry = NULL;
+       struct inode *ref_inode;
+       u64 last_ctime = 0;
+       u64 last_mtime = 0;
+       u64 last_atime = 0;
+
+       inode_for_each_dentry(dentry, inode) {
+               if (!ref_dentry || dentry->d_inode->num_ads > ref_dentry->d_inode->num_ads)
+                       ref_dentry = dentry;
+               if (dentry->d_inode->creation_time > last_ctime)
+                       last_ctime = dentry->d_inode->creation_time;
+               if (dentry->d_inode->last_write_time > last_mtime)
+                       last_mtime = dentry->d_inode->last_write_time;
+               if (dentry->d_inode->last_access_time > last_atime)
+                       last_atime = dentry->d_inode->last_access_time;
        }
-       if (!dentries_have_same_ads(owner, user)) {
-               mismatch_type = "Alternate Stream Entries";
-               goto mismatch;
+
+       ref_inode = ref_dentry->d_inode;
+       ref_inode->link_count = 1;
+       hlist_add_head(&ref_inode->hlist, inode_list);
+
+       list_del(&inode->dentry_list);
+       list_add(&ref_inode->dentry_list, &ref_dentry->inode_dentry_list);
+
+       inode_for_each_dentry(dentry, ref_inode) {
+               if (dentry != ref_dentry) {
+                       if (!inodes_consistent(ref_inode, dentry->d_inode)) {
+                               inconsistent_inode(ref_inode);
+                               return WIMLIB_ERR_INVALID_DENTRY;
+                       }
+                       /* Free the unneeded `struct inode'. */
+                       dentry->d_inode->hlist.next = NULL;
+                       dentry->d_inode->hlist.pprev = NULL;
+                       free_inode(dentry->d_inode);
+                       dentry->d_inode = ref_inode;
+                       ref_inode->link_count++;
+               }
        }
-       dentry_free_ads_entries(user);
-       user->ads_entries = owner->ads_entries;
-       user->ads_entries_status = ADS_ENTRIES_USER;
+       ref_inode->creation_time = last_ctime;
+       ref_inode->last_write_time = last_mtime;
+       ref_inode->last_access_time = last_atime;
+       wimlib_assert(inode_link_count(ref_inode) == ref_inode->link_count);
        return 0;
-mismatch:
-       WARNING("Dentries `%s' and `%s' in the same hard-link group but "
-               "do not share the same %s",
-               owner->full_path_utf8, user->full_path_utf8,
-               mismatch_type);
-       return WIMLIB_ERR_INVALID_DENTRY;
 }
 
-static int link_group_free_duplicate_data(struct link_group *group,
-                                         struct link_group **bad_links)
+/*
+ * Fixes up a nominal inode.
+ *
+ * By a nominal inode we mean a group of two or more dentries that share
+ * the same hard link group ID.
+ *
+ * If dentries in the inode are found to be inconsistent, we may split the inode
+ * into several "true" inodes.
+ *
+ * After splitting up each nominal inode into the "true" inodes we will
+ * canonicalize the link group by getting rid of all the unnecessary `struct
+ * inodes'.  There will be just one `struct inode' for each hard link group
+ * remaining.
+ */
+static int fix_nominal_inode(struct inode *inode,
+                            struct hlist_head *inode_list)
 {
-       struct dentry *owner, *user, *tmp;
-
-       owner = container_of(group->dentry_list, struct dentry,
-                             link_group_list);
-       owner->ads_entries_status = ADS_ENTRIES_OWNER;
-
-       list_for_each_entry_safe(user, tmp, group->dentry_list,
-                                link_group_list)
-       {
-               /* I would like it to be an error if two dentries are in the
-                * same hard link group but have irreconcilable differences such
-                * as different file permissions, but unfortunately some of M$'s
-                * WIMs contain many instances of this error.  This problem is
-                * worked around here by splitting each offending dentry off
-                * into its own hard link group. */
-               if (share_dentry_ads(owner, user) != 0) {
-                       struct link_group *single;
-                       single = MALLOC(sizeof(struct link_group));
-                       if (!single)
-                               return WIMLIB_ERR_NOMEM;
-                       list_del(&user->link_group_list);
-                       INIT_LIST_HEAD(&user->link_group_list);
-                       single->link_group_id = 0;
-                       single->next          = *bad_links;
-                       single->dentry_list   = &user->link_group_list;
-                       *bad_links            = single;
-                       user->ads_entries_status = ADS_ENTRIES_OWNER;
+       struct dentry *dentry;
+       struct hlist_node *cur, *tmp;
+       int ret;
+       size_t num_true_inodes;
+
+       wimlib_assert(inode->link_count == inode_link_count(inode));
+
+       LIST_HEAD(dentries_with_data_streams);
+       LIST_HEAD(dentries_with_no_data_streams);
+       HLIST_HEAD(true_inodes);
+
+        /* Create a list of dentries in the nominal inode that have at
+         * least one data stream with a non-zero hash, and another list that
+         * contains the dentries that have a zero hash for all data streams. */
+       inode_for_each_dentry(dentry, inode) {
+               for (unsigned i = 0; i <= dentry->d_inode->num_ads; i++) {
+                       const u8 *hash;
+                       hash = inode_stream_hash(dentry->d_inode, i);
+                       if (!is_zero_hash(hash)) {
+                               list_add(&dentry->tmp_list,
+                                        &dentries_with_data_streams);
+                               goto next_dentry;
+                       }
+               }
+               list_add(&dentry->tmp_list,
+                        &dentries_with_no_data_streams);
+       next_dentry:
+               ;
+       }
+
+       /* If there are no dentries with data streams, we require the nominal
+        * inode to be a true inode */
+       if (list_empty(&dentries_with_data_streams)) {
+       #ifdef ENABLE_DEBUG
+               if (inode->link_count > 1) {
+                       DEBUG("Found link group of size %u without "
+                             "any data streams:", inode->link_count);
+                       print_inode_dentries(inode);
+                       DEBUG("We are going to interpret it as true "
+                             "link group, provided that the dentries "
+                             "are consistent.");
+               }
+       #endif
+               return fix_true_inode(inode, inode_list);
+       }
+
+        /* One or more dentries had data streams specified.  We check each of
+         * these dentries for consistency with the others to form a set of true
+         * inodes. */
+       num_true_inodes = 0;
+       list_for_each_entry(dentry, &dentries_with_data_streams, tmp_list) {
+               /* Look for a true inode that is consistent with this dentry and
+                * add this dentry to it.  Or, if none of the true inodes are
+                * consistent with this dentry, add a new one (if that happens,
+                * we have split the hard link group). */
+               hlist_for_each_entry(inode, cur, &true_inodes, hlist) {
+                       if (ref_inodes_consistent(inode, dentry->d_inode)) {
+                               inode_add_dentry(dentry, inode);
+                               goto next_dentry_2;
+                       }
                }
+               num_true_inodes++;
+               INIT_LIST_HEAD(&dentry->d_inode->dentry_list);
+               inode_add_dentry(dentry, dentry->d_inode);
+               hlist_add_head(&dentry->d_inode->hlist, &true_inodes);
+next_dentry_2:
+               ;
+       }
+
+       wimlib_assert(num_true_inodes != 0);
+
+        /* If there were dentries with no data streams, we require there to only
+         * be one true inode so that we know which inode to assign the
+         * streamless dentries to. */
+       if (!list_empty(&dentries_with_no_data_streams)) {
+               if (num_true_inodes != 1) {
+                       ERROR("Hard inode ambiguity detected!");
+                       ERROR("We split up inode 0x%"PRIx64" due to "
+                             "inconsistencies,", inode->ino);
+                       ERROR("but dentries with no stream information remained. "
+                             "We don't know which inode");
+                       ERROR("to assign them to.");
+                       return WIMLIB_ERR_INVALID_DENTRY;
+               }
+               inode = container_of(true_inodes.first, struct inode, hlist);
+               /* Assign the streamless dentries to the one and only true
+                * inode. */
+               list_for_each_entry(dentry, &dentries_with_no_data_streams, tmp_list)
+                       inode_add_dentry(dentry, inode);
+       }
+       #ifdef ENABLE_DEBUG
+        if (num_true_inodes != 1) {
+               inode = container_of(true_inodes.first, struct inode, hlist);
+
+               printf("Split nominal inode 0x%"PRIx64" into %zu "
+                      "inodes:\n",
+                      inode->ino, num_true_inodes);
+               puts("------------------------------------------------------------------------------");
+               size_t i = 1;
+               hlist_for_each_entry(inode, cur, &true_inodes, hlist) {
+                       printf("[Split inode %zu]\n", i++);
+                       print_inode_dentries(inode);
+                       putchar('\n');
+               }
+               puts("------------------------------------------------------------------------------");
+        }
+       #endif
+
+       hlist_for_each_entry_safe(inode, cur, tmp, &true_inodes, hlist) {
+               ret = fix_true_inode(inode, inode_list);
+               if (ret != 0)
+                       return ret;
        }
        return 0;
 }
 
 /*
- * Goes through each link group and shares the ads_entries (Alternate Data
- * Stream entries) field of each dentry between members of a hard link group.
+ * Goes through each hard link group (dentries sharing the same hard link group
+ * ID field) that's been inserted into the inode table and shares the `struct
+ * inode's among members of each hard link group.
  *
- * In the process, the dentries in each link group are checked for consistency.
- * If they contain data features that indicate they cannot really be in the same
- * hard link group, this should be an error, but in reality this case needs to
- * be handled, so we split the dentries into different hard link groups.
+ * In the process, the dentries belonging to each inode are checked for
+ * consistency.  If they contain data features that indicate they cannot really
+ * correspond to the same inode, this should be an error, but in reality this
+ * case needs to be handled, so we split the dentries into different inodes.
  *
- * One of the dentries in the group is arbitrarily assigned the role of "owner"
- * (ADS_ENTRIES_OWNER), while the others are "users" (ADS_ENTRIES_USER).
+ * After this function returns, the inodes are no longer in the inode table, and
+ * the inode table should be destroyed.  A list of the inodes, including all
+ * split inodes as well as the inodes that were good before, is returned in the
+ * list @inode_list.
  */
-int link_groups_free_duplicate_data(struct link_group_table *table)
+static int fix_inodes(struct inode_table *table, struct hlist_head *inode_list)
 {
+       struct inode *inode;
+       struct hlist_node *cur, *tmp;
+       int ret;
+       INIT_HLIST_HEAD(inode_list);
        for (u64 i = 0; i < table->capacity; i++) {
-               struct link_group *group = table->array[i];
-               while (group) {
-                       int ret;
-                       ret = link_group_free_duplicate_data(group,
-                                                            &table->singles);
+               hlist_for_each_entry_safe(inode, cur, tmp, &table->array[i], hlist) {
+                       ret = fix_nominal_inode(inode, inode_list);
                        if (ret != 0)
                                return ret;
-                       group = group->next;
                }
        }
+       hlist_for_each_safe(cur, tmp, &table->extra_inodes)
+               hlist_add_head(cur, inode_list);
        return 0;
 }
+
+int dentry_tree_fix_inodes(struct dentry *root, struct hlist_head *inode_list)
+{
+       struct inode_table inode_tab;
+       int ret;
+
+       DEBUG("Inserting dentries into inode table");
+       ret = init_inode_table(&inode_tab, 9001);
+       if (ret != 0)
+               return ret;
+
+       for_dentry_in_tree(root, inode_table_insert, &inode_tab);
+
+       DEBUG("Cleaning up the hard link groups");
+       ret = fix_inodes(&inode_tab, inode_list);
+       destroy_inode_table(&inode_tab);
+       return ret;
+}