]> git.proxmox.com Git - mirror_ubuntu-artful-kernel.git/blobdiff - fs/btrfs/backref.c
btrfs: remove parameter blocksize from read_tree_block
[mirror_ubuntu-artful-kernel.git] / fs / btrfs / backref.c
index e25564bfcb463383e94eba0ce7f2f3769898afe7..2d3e32ebfd15510b8e97519a006486c83755121b 100644 (file)
@@ -25,6 +25,9 @@
 #include "delayed-ref.h"
 #include "locking.h"
 
+/* Just an arbitrary number so we can be sure this happened */
+#define BACKREF_FOUND_SHARED 6
+
 struct extent_inode_elem {
        u64 inum;
        u64 offset;
@@ -276,9 +279,8 @@ static int add_all_parents(struct btrfs_root *root, struct btrfs_path *path,
                        }
                        if (ret > 0)
                                goto next;
-                       ret = ulist_add_merge(parents, eb->start,
-                                             (uintptr_t)eie,
-                                             (u64 *)&old, GFP_NOFS);
+                       ret = ulist_add_merge_ptr(parents, eb->start,
+                                                 eie, (void **)&old, GFP_NOFS);
                        if (ret < 0)
                                break;
                        if (!ret && extent_item_pos) {
@@ -378,7 +380,8 @@ out:
 static int __resolve_indirect_refs(struct btrfs_fs_info *fs_info,
                                   struct btrfs_path *path, u64 time_seq,
                                   struct list_head *head,
-                                  const u64 *extent_item_pos, u64 total_refs)
+                                  const u64 *extent_item_pos, u64 total_refs,
+                                  u64 root_objectid)
 {
        int err;
        int ret = 0;
@@ -403,6 +406,10 @@ static int __resolve_indirect_refs(struct btrfs_fs_info *fs_info,
                        continue;
                if (ref->count == 0)
                        continue;
+               if (root_objectid && ref->root_id != root_objectid) {
+                       ret = BACKREF_FOUND_SHARED;
+                       goto out;
+               }
                err = __resolve_indirect_ref(fs_info, path, time_seq, ref,
                                             parents, extent_item_pos,
                                             total_refs);
@@ -483,7 +490,7 @@ static int __add_missing_keys(struct btrfs_fs_info *fs_info,
                        continue;
                BUG_ON(!ref->wanted_disk_byte);
                eb = read_tree_block(fs_info->tree_root, ref->wanted_disk_byte,
-                                    fs_info->tree_root->leafsize, 0);
+                                    0);
                if (!eb || !extent_buffer_uptodate(eb)) {
                        free_extent_buffer(eb);
                        return -EIO;
@@ -562,7 +569,8 @@ static void __merge_refs(struct list_head *head, int mode)
  * smaller or equal that seq to the list
  */
 static int __add_delayed_refs(struct btrfs_delayed_ref_head *head, u64 seq,
-                             struct list_head *prefs, u64 *total_refs)
+                             struct list_head *prefs, u64 *total_refs,
+                             u64 inum)
 {
        struct btrfs_delayed_extent_op *extent_op = head->extent_op;
        struct rb_node *n = &head->node.rb_node;
@@ -626,6 +634,16 @@ static int __add_delayed_refs(struct btrfs_delayed_ref_head *head, u64 seq,
                        key.objectid = ref->objectid;
                        key.type = BTRFS_EXTENT_DATA_KEY;
                        key.offset = ref->offset;
+
+                       /*
+                        * Found a inum that doesn't match our known inum, we
+                        * know it's shared.
+                        */
+                       if (inum && ref->objectid != inum) {
+                               ret = BACKREF_FOUND_SHARED;
+                               break;
+                       }
+
                        ret = __add_prelim_ref(prefs, ref->root, &key, 0, 0,
                                               node->bytenr,
                                               node->ref_mod * sgn, GFP_ATOMIC);
@@ -660,7 +678,7 @@ static int __add_delayed_refs(struct btrfs_delayed_ref_head *head, u64 seq,
 static int __add_inline_refs(struct btrfs_fs_info *fs_info,
                             struct btrfs_path *path, u64 bytenr,
                             int *info_level, struct list_head *prefs,
-                            u64 *total_refs)
+                            u64 *total_refs, u64 inum)
 {
        int ret = 0;
        int slot;
@@ -745,6 +763,12 @@ static int __add_inline_refs(struct btrfs_fs_info *fs_info,
                                                                      dref);
                        key.type = BTRFS_EXTENT_DATA_KEY;
                        key.offset = btrfs_extent_data_ref_offset(leaf, dref);
+
+                       if (inum && key.objectid != inum) {
+                               ret = BACKREF_FOUND_SHARED;
+                               break;
+                       }
+
                        root = btrfs_extent_data_ref_root(leaf, dref);
                        ret = __add_prelim_ref(prefs, root, &key, 0, 0,
                                               bytenr, count, GFP_NOFS);
@@ -766,7 +790,7 @@ static int __add_inline_refs(struct btrfs_fs_info *fs_info,
  */
 static int __add_keyed_refs(struct btrfs_fs_info *fs_info,
                            struct btrfs_path *path, u64 bytenr,
-                           int info_level, struct list_head *prefs)
+                           int info_level, struct list_head *prefs, u64 inum)
 {
        struct btrfs_root *extent_root = fs_info->extent_root;
        int ret;
@@ -828,6 +852,12 @@ static int __add_keyed_refs(struct btrfs_fs_info *fs_info,
                                                                      dref);
                        key.type = BTRFS_EXTENT_DATA_KEY;
                        key.offset = btrfs_extent_data_ref_offset(leaf, dref);
+
+                       if (inum && key.objectid != inum) {
+                               ret = BACKREF_FOUND_SHARED;
+                               break;
+                       }
+
                        root = btrfs_extent_data_ref_root(leaf, dref);
                        ret = __add_prelim_ref(prefs, root, &key, 0, 0,
                                               bytenr, count, GFP_NOFS);
@@ -855,7 +885,8 @@ static int __add_keyed_refs(struct btrfs_fs_info *fs_info,
 static int find_parent_nodes(struct btrfs_trans_handle *trans,
                             struct btrfs_fs_info *fs_info, u64 bytenr,
                             u64 time_seq, struct ulist *refs,
-                            struct ulist *roots, const u64 *extent_item_pos)
+                            struct ulist *roots, const u64 *extent_item_pos,
+                            u64 root_objectid, u64 inum)
 {
        struct btrfs_key key;
        struct btrfs_path *path;
@@ -930,7 +961,8 @@ again:
                        }
                        spin_unlock(&delayed_refs->lock);
                        ret = __add_delayed_refs(head, time_seq,
-                                                &prefs_delayed, &total_refs);
+                                                &prefs_delayed, &total_refs,
+                                                inum);
                        mutex_unlock(&head->mutex);
                        if (ret)
                                goto out;
@@ -952,11 +984,11 @@ again:
                     key.type == BTRFS_METADATA_ITEM_KEY)) {
                        ret = __add_inline_refs(fs_info, path, bytenr,
                                                &info_level, &prefs,
-                                               &total_refs);
+                                               &total_refs, inum);
                        if (ret)
                                goto out;
                        ret = __add_keyed_refs(fs_info, path, bytenr,
-                                              info_level, &prefs);
+                                              info_level, &prefs, inum);
                        if (ret)
                                goto out;
                }
@@ -972,7 +1004,8 @@ again:
        __merge_refs(&prefs, 1);
 
        ret = __resolve_indirect_refs(fs_info, path, time_seq, &prefs,
-                                     extent_item_pos, total_refs);
+                                     extent_item_pos, total_refs,
+                                     root_objectid);
        if (ret)
                goto out;
 
@@ -982,6 +1015,11 @@ again:
                ref = list_first_entry(&prefs, struct __prelim_ref, list);
                WARN_ON(ref->count < 0);
                if (roots && ref->count && ref->root_id && ref->parent == 0) {
+                       if (root_objectid && ref->root_id != root_objectid) {
+                               ret = BACKREF_FOUND_SHARED;
+                               goto out;
+                       }
+
                        /* no parent == root of tree */
                        ret = ulist_add(roots, ref->root_id, 0, GFP_NOFS);
                        if (ret < 0)
@@ -990,27 +1028,28 @@ again:
                if (ref->count && ref->parent) {
                        if (extent_item_pos && !ref->inode_list &&
                            ref->level == 0) {
-                               u32 bsz;
                                struct extent_buffer *eb;
-                               bsz = btrfs_level_size(fs_info->extent_root,
-                                                       ref->level);
+
                                eb = read_tree_block(fs_info->extent_root,
-                                                          ref->parent, bsz, 0);
+                                                          ref->parent, 0);
                                if (!eb || !extent_buffer_uptodate(eb)) {
                                        free_extent_buffer(eb);
                                        ret = -EIO;
                                        goto out;
                                }
+                               btrfs_tree_read_lock(eb);
+                               btrfs_set_lock_blocking_rw(eb, BTRFS_READ_LOCK);
                                ret = find_extent_in_eb(eb, bytenr,
                                                        *extent_item_pos, &eie);
+                               btrfs_tree_read_unlock_blocking(eb);
                                free_extent_buffer(eb);
                                if (ret < 0)
                                        goto out;
                                ref->inode_list = eie;
                        }
-                       ret = ulist_add_merge(refs, ref->parent,
-                                             (uintptr_t)ref->inode_list,
-                                             (u64 *)&eie, GFP_NOFS);
+                       ret = ulist_add_merge_ptr(refs, ref->parent,
+                                                 ref->inode_list,
+                                                 (void **)&eie, GFP_NOFS);
                        if (ret < 0)
                                goto out;
                        if (!ret && extent_item_pos) {
@@ -1085,7 +1124,7 @@ static int btrfs_find_all_leafs(struct btrfs_trans_handle *trans,
                return -ENOMEM;
 
        ret = find_parent_nodes(trans, fs_info, bytenr,
-                               time_seq, *leafs, NULL, extent_item_pos);
+                               time_seq, *leafs, NULL, extent_item_pos, 0, 0);
        if (ret < 0 && ret != -ENOENT) {
                free_leaf_list(*leafs);
                return ret;
@@ -1128,7 +1167,7 @@ static int __btrfs_find_all_roots(struct btrfs_trans_handle *trans,
        ULIST_ITER_INIT(&uiter);
        while (1) {
                ret = find_parent_nodes(trans, fs_info, bytenr,
-                                       time_seq, tmp, *roots, NULL);
+                                       time_seq, tmp, *roots, NULL, 0, 0);
                if (ret < 0 && ret != -ENOENT) {
                        ulist_free(tmp);
                        ulist_free(*roots);
@@ -1159,6 +1198,54 @@ int btrfs_find_all_roots(struct btrfs_trans_handle *trans,
        return ret;
 }
 
+int btrfs_check_shared(struct btrfs_trans_handle *trans,
+                      struct btrfs_fs_info *fs_info, u64 root_objectid,
+                      u64 inum, u64 bytenr)
+{
+       struct ulist *tmp = NULL;
+       struct ulist *roots = NULL;
+       struct ulist_iterator uiter;
+       struct ulist_node *node;
+       struct seq_list elem = {};
+       int ret = 0;
+
+       tmp = ulist_alloc(GFP_NOFS);
+       roots = ulist_alloc(GFP_NOFS);
+       if (!tmp || !roots) {
+               ulist_free(tmp);
+               ulist_free(roots);
+               return -ENOMEM;
+       }
+
+       if (trans)
+               btrfs_get_tree_mod_seq(fs_info, &elem);
+       else
+               down_read(&fs_info->commit_root_sem);
+       ULIST_ITER_INIT(&uiter);
+       while (1) {
+               ret = find_parent_nodes(trans, fs_info, bytenr, elem.seq, tmp,
+                                       roots, NULL, root_objectid, inum);
+               if (ret == BACKREF_FOUND_SHARED) {
+                       ret = 1;
+                       break;
+               }
+               if (ret < 0 && ret != -ENOENT)
+                       break;
+               node = ulist_next(tmp, &uiter);
+               if (!node)
+                       break;
+               bytenr = node->val;
+               cond_resched();
+       }
+       if (trans)
+               btrfs_put_tree_mod_seq(fs_info, &elem);
+       else
+               up_read(&fs_info->commit_root_sem);
+       ulist_free(tmp);
+       ulist_free(roots);
+       return ret;
+}
+
 /*
  * this makes the path point to (inum INODE_ITEM ioff)
  */
@@ -1191,7 +1278,7 @@ int btrfs_find_one_extref(struct btrfs_root *root, u64 inode_objectid,
        unsigned long ptr;
 
        key.objectid = inode_objectid;
-       btrfs_set_key_type(&key, BTRFS_INODE_EXTREF_KEY);
+       key.type = BTRFS_INODE_EXTREF_KEY;
        key.offset = start_off;
 
        ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
@@ -1231,7 +1318,7 @@ int btrfs_find_one_extref(struct btrfs_root *root, u64 inode_objectid,
                ret = -ENOENT;
                if (found_key.objectid != inode_objectid)
                        break;
-               if (btrfs_key_type(&found_key) != BTRFS_INODE_EXTREF_KEY)
+               if (found_key.type != BTRFS_INODE_EXTREF_KEY)
                        break;
 
                ret = 0;
@@ -1364,7 +1451,7 @@ int extent_from_logical(struct btrfs_fs_info *fs_info, u64 logical,
        }
        btrfs_item_key_to_cpu(path->nodes[0], found_key, path->slots[0]);
        if (found_key->type == BTRFS_METADATA_ITEM_KEY)
-               size = fs_info->extent_root->leafsize;
+               size = fs_info->extent_root->nodesize;
        else if (found_key->type == BTRFS_EXTENT_ITEM_KEY)
                size = found_key->offset;