btrfs-progs: docs: add missing short option for qroup-report
[platform/upstream/btrfs-progs.git] / cmds-check.c
index cf58f95..f6320b2 100644 (file)
@@ -40,7 +40,9 @@
 #include "qgroup-verify.h"
 #include "rbtree-utils.h"
 #include "backref.h"
-#include "ulist.h"
+#include "kernel-shared/ulist.h"
+#include "hash.h"
+#include "help.h"
 
 enum task_position {
        TASK_EXTENTS,
@@ -112,6 +114,24 @@ struct data_backref {
        u32 found_ref;
 };
 
+#define ROOT_DIR_ERROR         (1<<1)  /* bad ROOT_DIR */
+#define DIR_ITEM_MISSING       (1<<2)  /* DIR_ITEM not found */
+#define DIR_ITEM_MISMATCH      (1<<3)  /* DIR_ITEM found but not match */
+#define INODE_REF_MISSING      (1<<4)  /* INODE_REF/INODE_EXTREF not found */
+#define INODE_ITEM_MISSING     (1<<5)  /* INODE_ITEM not found */
+#define INODE_ITEM_MISMATCH    (1<<6)  /* INODE_ITEM found but not match */
+#define FILE_EXTENT_ERROR      (1<<7)  /* bad FILE_EXTENT */
+#define ODD_CSUM_ITEM          (1<<8)  /* CSUM_ITEM error */
+#define CSUM_ITEM_MISSING      (1<<9)  /* CSUM_ITEM not found */
+#define LINK_COUNT_ERROR       (1<<10) /* INODE_ITEM nlink count error */
+#define NBYTES_ERROR           (1<<11) /* INODE_ITEM nbytes count error */
+#define ISIZE_ERROR            (1<<12) /* INODE_ITEM size count error */
+#define ORPHAN_ITEM            (1<<13) /* INODE_ITEM no reference */
+#define NO_INODE_ITEM          (1<<14) /* no inode_item */
+#define LAST_ITEM              (1<<15) /* Complete this tree traversal */
+#define ROOT_REF_MISSING       (1<<16) /* ROOT_REF not found */
+#define ROOT_REF_MISMATCH      (1<<17) /* ROOT_REF found but not match */
+
 static inline struct data_backref* to_data_backref(struct extent_backref *back)
 {
        return container_of(back, struct data_backref, node);
@@ -809,7 +829,8 @@ static void print_inode_error(struct btrfs_root *root, struct inode_record *rec)
                }
                if (!found)
                        fprintf(stderr, "\tstart: 0, len: %llu\n",
-                               round_up(rec->isize, root->sectorsize));
+                               round_up(rec->isize,
+                                        root->fs_info->sectorsize));
        }
 }
 
@@ -1458,8 +1479,7 @@ out:
        return has_parent ? 0 : 2;
 }
 
-static int process_dir_item(struct btrfs_root *root,
-                           struct extent_buffer *eb,
+static int process_dir_item(struct extent_buffer *eb,
                            int slot, struct btrfs_key *key,
                            struct shared_node *active_node)
 {
@@ -1493,15 +1513,29 @@ static int process_dir_item(struct btrfs_root *root,
                filetype = btrfs_dir_type(eb, di);
 
                rec->found_size += name_len;
-               if (name_len <= BTRFS_NAME_LEN) {
+               if (cur + sizeof(*di) + name_len > total ||
+                   name_len > BTRFS_NAME_LEN) {
+                       error = REF_ERR_NAME_TOO_LONG;
+
+                       if (cur + sizeof(*di) > total)
+                               break;
+                       len = min_t(u32, total - cur - sizeof(*di),
+                                   BTRFS_NAME_LEN);
+               } else {
                        len = name_len;
                        error = 0;
-               } else {
-                       len = BTRFS_NAME_LEN;
-                       error = REF_ERR_NAME_TOO_LONG;
                }
+
                read_extent_buffer(eb, namebuf, (unsigned long)(di + 1), len);
 
+               if (key->type == BTRFS_DIR_ITEM_KEY &&
+                   key->offset != btrfs_name_hash(namebuf, len)) {
+                       rec->errors |= I_ERR_ODD_DIR_ITEM;
+                       error("DIR_ITEM[%llu %llu] name %s namelen %u filetype %u mismatch with its hash, wanted %llu have %llu",
+                       key->objectid, key->offset, namebuf, len, filetype,
+                       key->offset, btrfs_name_hash(namebuf, len));
+               }
+
                if (location.type == BTRFS_INODE_ITEM_KEY) {
                        add_inode_backref(inode_cache, location.objectid,
                                          key->objectid, key->offset, namebuf,
@@ -1550,13 +1584,22 @@ static int process_inode_ref(struct extent_buffer *eb,
        while (cur < total) {
                name_len = btrfs_inode_ref_name_len(eb, ref);
                index = btrfs_inode_ref_index(eb, ref);
-               if (name_len <= BTRFS_NAME_LEN) {
+
+               /* inode_ref + namelen should not cross item boundary */
+               if (cur + sizeof(*ref) + name_len > total ||
+                   name_len > BTRFS_NAME_LEN) {
+                       if (total < cur + sizeof(*ref))
+                               break;
+
+                       /* Still try to read out the remaining part */
+                       len = min_t(u32, total - cur - sizeof(*ref),
+                                   BTRFS_NAME_LEN);
+                       error = REF_ERR_NAME_TOO_LONG;
+               } else {
                        len = name_len;
                        error = 0;
-               } else {
-                       len = BTRFS_NAME_LEN;
-                       error = REF_ERR_NAME_TOO_LONG;
                }
+
                read_extent_buffer(eb, namebuf, (unsigned long)(ref + 1), len);
                add_inode_backref(inode_cache, key->objectid, key->offset,
                                  index, namebuf, len, 0, key->type, error);
@@ -1665,7 +1708,8 @@ static int count_csum_range(struct btrfs_root *root, u64 start,
                        start = key.offset;
 
                size = btrfs_item_size_nr(leaf, path.slots[0]);
-               csum_end = key.offset + (size / csum_size) * root->sectorsize;
+               csum_end = key.offset + (size / csum_size) *
+                          root->fs_info->sectorsize;
                if (csum_end > start) {
                        size = min(csum_end - start, len);
                        len -= size;
@@ -1692,7 +1736,7 @@ static int process_file_extent(struct btrfs_root *root,
        u64 num_bytes = 0;
        u64 disk_bytenr = 0;
        u64 extent_offset = 0;
-       u64 mask = root->sectorsize - 1;
+       u64 mask = root->fs_info->sectorsize - 1;
        int extent_type;
        int ret;
 
@@ -1816,7 +1860,7 @@ static int process_one_leaf(struct btrfs_root *root, struct extent_buffer *eb,
                switch (key.type) {
                case BTRFS_DIR_ITEM_KEY:
                case BTRFS_DIR_INDEX_KEY:
-                       ret = process_dir_item(root, eb, i, &key, active_node);
+                       ret = process_dir_item(eb, i, &key, active_node);
                        break;
                case BTRFS_INODE_REF_KEY:
                        ret = process_inode_ref(eb, i, &key, active_node);
@@ -1838,9 +1882,100 @@ static int process_one_leaf(struct btrfs_root *root, struct extent_buffer *eb,
        return ret;
 }
 
+struct node_refs {
+       u64 bytenr[BTRFS_MAX_LEVEL];
+       u64 refs[BTRFS_MAX_LEVEL];
+       int need_check[BTRFS_MAX_LEVEL];
+};
+
+static int update_nodes_refs(struct btrfs_root *root, u64 bytenr,
+                            struct node_refs *nrefs, u64 level);
+static int check_inode_item(struct btrfs_root *root, struct btrfs_path *path,
+                           unsigned int ext_ref);
+
+/*
+ * Returns >0  Found error, not fatal, should continue
+ * Returns <0  Fatal error, must exit the whole check
+ * Returns 0   No errors found
+ */
+static int process_one_leaf_v2(struct btrfs_root *root, struct btrfs_path *path,
+                              struct node_refs *nrefs, int *level, int ext_ref)
+{
+       struct extent_buffer *cur = path->nodes[0];
+       struct btrfs_key key;
+       u64 cur_bytenr;
+       u32 nritems;
+       u64 first_ino = 0;
+       int root_level = btrfs_header_level(root->node);
+       int i;
+       int ret = 0; /* Final return value */
+       int err = 0; /* Positive error bitmap */
+
+       cur_bytenr = cur->start;
+
+       /* skip to first inode item or the first inode number change */
+       nritems = btrfs_header_nritems(cur);
+       for (i = 0; i < nritems; i++) {
+               btrfs_item_key_to_cpu(cur, &key, i);
+               if (i == 0)
+                       first_ino = key.objectid;
+               if (key.type == BTRFS_INODE_ITEM_KEY ||
+                   (first_ino && first_ino != key.objectid))
+                       break;
+       }
+       if (i == nritems) {
+               path->slots[0] = nritems;
+               return 0;
+       }
+       path->slots[0] = i;
+
+again:
+       err |= check_inode_item(root, path, ext_ref);
+
+       if (err & LAST_ITEM)
+               goto out;
+
+       /* still have inode items in thie leaf */
+       if (cur->start == cur_bytenr)
+               goto again;
+
+       /*
+        * we have switched to another leaf, above nodes may
+        * have changed, here walk down the path, if a node
+        * or leaf is shared, check whether we can skip this
+        * node or leaf.
+        */
+       for (i = root_level; i >= 0; i--) {
+               if (path->nodes[i]->start == nrefs->bytenr[i])
+                       continue;
+
+               ret = update_nodes_refs(root,
+                               path->nodes[i]->start,
+                               nrefs, i);
+               if (ret)
+                       goto out;
+
+               if (!nrefs->need_check[i]) {
+                       *level += 1;
+                       break;
+               }
+       }
+
+       for (i = 0; i < *level; i++) {
+               free_extent_buffer(path->nodes[i]);
+               path->nodes[i] = NULL;
+       }
+out:
+       err &= ~LAST_ITEM;
+       if (err && !ret)
+               ret = err;
+       return ret;
+}
+
 static void reada_walk_down(struct btrfs_root *root,
                            struct extent_buffer *node, int slot)
 {
+       struct btrfs_fs_info *fs_info = root->fs_info;
        u64 bytenr;
        u64 ptr_gen;
        u32 nritems;
@@ -1853,11 +1988,11 @@ static void reada_walk_down(struct btrfs_root *root,
                return;
 
        nritems = btrfs_header_nritems(node);
-       blocksize = root->nodesize;
+       blocksize = fs_info->nodesize;
        for (i = slot; i < nritems; i++) {
                bytenr = btrfs_node_blockptr(node, i);
                ptr_gen = btrfs_node_ptr_generation(node, i);
-               readahead_tree_block(root, bytenr, blocksize, ptr_gen);
+               readahead_tree_block(fs_info, bytenr, blocksize, ptr_gen);
        }
 }
 
@@ -1874,8 +2009,7 @@ static void reada_walk_down(struct btrfs_root *root,
  * which makes leaf owner check not so strong, key check should be
  * sufficient enough for that case.
  */
-static int check_child_node(struct btrfs_root *root,
-                           struct extent_buffer *parent, int slot,
+static int check_child_node(struct extent_buffer *parent, int slot,
                            struct extent_buffer *child)
 {
        struct btrfs_key parent_key;
@@ -1911,10 +2045,66 @@ static int check_child_node(struct btrfs_root *root,
        return ret;
 }
 
-struct node_refs {
-       u64 bytenr[BTRFS_MAX_LEVEL];
-       u64 refs[BTRFS_MAX_LEVEL];
-};
+/*
+ * for a tree node or leaf, if it's shared, indeed we don't need to iterate it
+ * in every fs or file tree check. Here we find its all root ids, and only check
+ * it in the fs or file tree which has the smallest root id.
+ */
+static int need_check(struct btrfs_root *root, struct ulist *roots)
+{
+       struct rb_node *node;
+       struct ulist_node *u;
+
+       if (roots->nnodes == 1)
+               return 1;
+
+       node = rb_first(&roots->root);
+       u = rb_entry(node, struct ulist_node, rb_node);
+       /*
+        * current root id is not smallest, we skip it and let it be checked
+        * in the fs or file tree who hash the smallest root id.
+        */
+       if (root->objectid != u->val)
+               return 0;
+
+       return 1;
+}
+
+/*
+ * for a tree node or leaf, we record its reference count, so later if we still
+ * process this node or leaf, don't need to compute its reference count again.
+ */
+static int update_nodes_refs(struct btrfs_root *root, u64 bytenr,
+                            struct node_refs *nrefs, u64 level)
+{
+       int check, ret;
+       u64 refs;
+       struct ulist *roots;
+
+       if (nrefs->bytenr[level] != bytenr) {
+               ret = btrfs_lookup_extent_info(NULL, root, bytenr,
+                                      level, 1, &refs, NULL);
+               if (ret < 0)
+                       return ret;
+
+               nrefs->bytenr[level] = bytenr;
+               nrefs->refs[level] = refs;
+               if (refs > 1) {
+                       ret = btrfs_find_all_roots(NULL, root->fs_info, bytenr,
+                                                  0, &roots);
+                       if (ret)
+                               return -EIO;
+
+                       check = need_check(root, roots);
+                       ulist_free(roots);
+                       nrefs->need_check[level] = check;
+               } else {
+                       nrefs->need_check[level] = 1;
+               }
+       }
+
+       return 0;
+}
 
 static int walk_down_tree(struct btrfs_root *root, struct btrfs_path *path,
                          struct walk_control *wc, int *level,
@@ -1923,6 +2113,7 @@ static int walk_down_tree(struct btrfs_root *root, struct btrfs_path *path,
        enum btrfs_tree_block_status status;
        u64 bytenr;
        u64 ptr_gen;
+       struct btrfs_fs_info *fs_info = root->fs_info;
        struct extent_buffer *next;
        struct extent_buffer *cur;
        u32 blocksize;
@@ -1974,7 +2165,7 @@ static int walk_down_tree(struct btrfs_root *root, struct btrfs_path *path,
                }
                bytenr = btrfs_node_blockptr(cur, path->slots[*level]);
                ptr_gen = btrfs_node_ptr_generation(cur, path->slots[*level]);
-               blocksize = root->nodesize;
+               blocksize = fs_info->nodesize;
 
                if (bytenr == nrefs->bytenr[*level - 1]) {
                        refs = nrefs->refs[*level - 1];
@@ -1998,11 +2189,11 @@ static int walk_down_tree(struct btrfs_root *root, struct btrfs_path *path,
                        }
                }
 
-               next = btrfs_find_tree_block(root, bytenr, blocksize);
+               next = btrfs_find_tree_block(fs_info, bytenr, blocksize);
                if (!next || !btrfs_buffer_uptodate(next, ptr_gen)) {
                        free_extent_buffer(next);
                        reada_walk_down(root, cur, path->slots[*level]);
-                       next = read_tree_block(root, bytenr, blocksize,
+                       next = read_tree_block(root->fs_info, bytenr, blocksize,
                                               ptr_gen);
                        if (!extent_buffer_uptodate(next)) {
                                struct btrfs_key node_key;
@@ -2013,14 +2204,16 @@ static int walk_down_tree(struct btrfs_root *root, struct btrfs_path *path,
                                btrfs_add_corrupt_extent_record(root->fs_info,
                                                &node_key,
                                                path->nodes[*level]->start,
-                                               root->nodesize, *level);
+                                               root->fs_info->nodesize,
+                                               *level);
                                err = -EIO;
                                goto out;
                        }
                }
 
-               ret = check_child_node(root, cur, path->slots[*level], next);
+               ret = check_child_node(cur, path->slots[*level], next);
                if (ret) {
+                       free_extent_buffer(next);
                        err = ret;
                        goto out;
                }
@@ -2045,6 +2238,117 @@ out:
        return err;
 }
 
+static int check_inode_item(struct btrfs_root *root, struct btrfs_path *path,
+                           unsigned int ext_ref);
+
+/*
+ * Returns >0  Found error, should continue
+ * Returns <0  Fatal error, must exit the whole check
+ * Returns 0   No errors found
+ */
+static int walk_down_tree_v2(struct btrfs_root *root, struct btrfs_path *path,
+                            int *level, struct node_refs *nrefs, int ext_ref)
+{
+       enum btrfs_tree_block_status status;
+       u64 bytenr;
+       u64 ptr_gen;
+       struct btrfs_fs_info *fs_info = root->fs_info;
+       struct extent_buffer *next;
+       struct extent_buffer *cur;
+       u32 blocksize;
+       int ret;
+
+       WARN_ON(*level < 0);
+       WARN_ON(*level >= BTRFS_MAX_LEVEL);
+
+       ret = update_nodes_refs(root, path->nodes[*level]->start,
+                               nrefs, *level);
+       if (ret < 0)
+               return ret;
+
+       while (*level >= 0) {
+               WARN_ON(*level < 0);
+               WARN_ON(*level >= BTRFS_MAX_LEVEL);
+               cur = path->nodes[*level];
+
+               if (btrfs_header_level(cur) != *level)
+                       WARN_ON(1);
+
+               if (path->slots[*level] >= btrfs_header_nritems(cur))
+                       break;
+               /* Don't forgot to check leaf/node validation */
+               if (*level == 0) {
+                       ret = btrfs_check_leaf(root, NULL, cur);
+                       if (ret != BTRFS_TREE_BLOCK_CLEAN) {
+                               ret = -EIO;
+                               break;
+                       }
+                       ret = process_one_leaf_v2(root, path, nrefs,
+                                                 level, ext_ref);
+                       break;
+               } else {
+                       ret = btrfs_check_node(root, NULL, cur);
+                       if (ret != BTRFS_TREE_BLOCK_CLEAN) {
+                               ret = -EIO;
+                               break;
+                       }
+               }
+               bytenr = btrfs_node_blockptr(cur, path->slots[*level]);
+               ptr_gen = btrfs_node_ptr_generation(cur, path->slots[*level]);
+               blocksize = fs_info->nodesize;
+
+               ret = update_nodes_refs(root, bytenr, nrefs, *level - 1);
+               if (ret)
+                       break;
+               if (!nrefs->need_check[*level - 1]) {
+                       path->slots[*level]++;
+                       continue;
+               }
+
+               next = btrfs_find_tree_block(fs_info, bytenr, blocksize);
+               if (!next || !btrfs_buffer_uptodate(next, ptr_gen)) {
+                       free_extent_buffer(next);
+                       reada_walk_down(root, cur, path->slots[*level]);
+                       next = read_tree_block(fs_info, bytenr, blocksize,
+                                              ptr_gen);
+                       if (!extent_buffer_uptodate(next)) {
+                               struct btrfs_key node_key;
+
+                               btrfs_node_key_to_cpu(path->nodes[*level],
+                                                     &node_key,
+                                                     path->slots[*level]);
+                               btrfs_add_corrupt_extent_record(fs_info,
+                                               &node_key,
+                                               path->nodes[*level]->start,
+                                               fs_info->nodesize,
+                                               *level);
+                               ret = -EIO;
+                               break;
+                       }
+               }
+
+               ret = check_child_node(cur, path->slots[*level], next);
+               if (ret < 0) 
+                       break;
+
+               if (btrfs_is_leaf(next))
+                       status = btrfs_check_leaf(root, NULL, next);
+               else
+                       status = btrfs_check_node(root, NULL, next);
+               if (status != BTRFS_TREE_BLOCK_CLEAN) {
+                       free_extent_buffer(next);
+                       ret = -EIO;
+                       break;
+               }
+
+               *level = *level - 1;
+               free_extent_buffer(path->nodes[*level]);
+               path->nodes[*level] = next;
+               path->slots[*level] = 0;
+       }
+       return ret;
+}
+
 static int walk_up_tree(struct btrfs_root *root, struct btrfs_path *path,
                        struct walk_control *wc, int *level)
 {
@@ -2069,6 +2373,27 @@ static int walk_up_tree(struct btrfs_root *root, struct btrfs_path *path,
        return 1;
 }
 
+static int walk_up_tree_v2(struct btrfs_root *root, struct btrfs_path *path,
+                          int *level)
+{
+       int i;
+       struct extent_buffer *leaf;
+
+       for (i = *level; i < BTRFS_MAX_LEVEL - 1 && path->nodes[i]; i++) {
+               leaf = path->nodes[i];
+               if (path->slots[i] + 1 < btrfs_header_nritems(leaf)) {
+                       path->slots[i]++;
+                       *level = i;
+                       return 0;
+               } else {
+                       free_extent_buffer(path->nodes[*level]);
+                       path->nodes[*level] = NULL;
+                       *level = i + 1;
+               }
+       }
+       return 1;
+}
+
 static int check_root_dir(struct inode_record *rec)
 {
        struct inode_backref *backref;
@@ -2244,8 +2569,6 @@ static int add_missing_dir_index(struct btrfs_root *root,
 }
 
 static int delete_dir_index(struct btrfs_root *root,
-                           struct cache_tree *inode_cache,
-                           struct inode_record *rec,
                            struct inode_backref *backref)
 {
        struct btrfs_trans_handle *trans;
@@ -2287,7 +2610,7 @@ static int delete_dir_index(struct btrfs_root *root,
 
 static int create_inode_item(struct btrfs_root *root,
                             struct inode_record *rec,
-                            struct inode_backref *backref, int root_dir)
+                            int root_dir)
 {
        struct btrfs_trans_handle *trans;
        struct btrfs_inode_item inode_item;
@@ -2353,7 +2676,7 @@ static int repair_inode_backrefs(struct btrfs_root *root,
        list_for_each_entry_safe(backref, tmp, &rec->backrefs, list) {
                if (!delete && rec->ino == root_dirid) {
                        if (!rec->found_inode_item) {
-                               ret = create_inode_item(root, rec, backref, 1);
+                               ret = create_inode_item(root, rec, 1);
                                if (ret)
                                        break;
                                repaired++;
@@ -2368,12 +2691,13 @@ static int repair_inode_backrefs(struct btrfs_root *root,
                    ((backref->found_dir_index && !backref->found_inode_ref) ||
                     (backref->found_dir_index && backref->found_inode_ref &&
                      (backref->errors & REF_ERR_INDEX_UNMATCH)))) {
-                       ret = delete_dir_index(root, inode_cache, rec, backref);
+                       ret = delete_dir_index(root, backref);
                        if (ret)
                                break;
                        repaired++;
                        list_del(&backref->list);
                        free(backref);
+                       continue;
                }
 
                if (!delete && !backref->found_dir_index &&
@@ -2384,12 +2708,12 @@ static int repair_inode_backrefs(struct btrfs_root *root,
                                break;
                        repaired++;
                        if (backref->found_dir_item &&
-                           backref->found_dir_index &&
                            backref->found_dir_index) {
                                if (!backref->errors &&
                                    backref->found_inode_ref) {
                                        list_del(&backref->list);
                                        free(backref);
+                                       continue;
                                }
                        }
                }
@@ -2439,7 +2763,7 @@ static int repair_inode_backrefs(struct btrfs_root *root,
                                backref->found_dir_item &&
                                !(backref->errors & REF_ERR_INDEX_UNMATCH) &&
                                !rec->found_inode_item)) {
-                       ret = create_inode_item(root, rec, backref, 0);
+                       ret = create_inode_item(root, rec, 0);
                        if (ret)
                                break;
                        repaired++;
@@ -2563,6 +2887,31 @@ out:
        return ret;
 }
 
+static int get_highest_inode(struct btrfs_trans_handle *trans,
+                               struct btrfs_root *root,
+                               struct btrfs_path *path,
+                               u64 *highest_ino)
+{
+       struct btrfs_key key, found_key;
+       int ret;
+
+       btrfs_init_path(path);
+       key.objectid = BTRFS_LAST_FREE_OBJECTID;
+       key.offset = -1;
+       key.type = BTRFS_INODE_ITEM_KEY;
+       ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
+       if (ret == 1) {
+               btrfs_item_key_to_cpu(path->nodes[0], &found_key,
+                               path->slots[0] - 1);
+               *highest_ino = found_key.objectid;
+               ret = 0;
+       }
+       if (*highest_ino >= BTRFS_LAST_FREE_OBJECTID)
+               ret = -EOVERFLOW;
+       btrfs_release_path(path);
+       return ret;
+}
+
 static int repair_inode_nlinks(struct btrfs_trans_handle *trans,
                               struct btrfs_root *root,
                               struct btrfs_path *path,
@@ -2608,11 +2957,9 @@ static int repair_inode_nlinks(struct btrfs_trans_handle *trans,
        }
 
        if (rec->found_link == 0) {
-               lost_found_ino = root->highest_inode;
-               if (lost_found_ino >= BTRFS_LAST_FREE_OBJECTID) {
-                       ret = -EOVERFLOW;
+               ret = get_highest_inode(trans, root, path, &lost_found_ino);
+               if (ret < 0)
                        goto out;
-               }
                lost_found_ino++;
                ret = btrfs_mkdir(trans, root, dir_name, strlen(dir_name),
                                  BTRFS_FIRST_FREE_OBJECTID, &lost_found_ino,
@@ -2900,7 +3247,8 @@ static int repair_inode_discount_extent(struct btrfs_trans_handle *trans,
        /* special case for a file losing all its file extent */
        if (!found) {
                ret = btrfs_punch_hole(trans, root, rec->ino, 0,
-                                      round_up(rec->isize, root->sectorsize));
+                                      round_up(rec->isize,
+                                               root->fs_info->sectorsize));
                if (ret < 0)
                        goto out;
        }
@@ -2976,21 +3324,6 @@ static int check_inode_recs(struct btrfs_root *root,
        }
 
        /*
-        * We need to record the highest inode number for later 'lost+found'
-        * dir creation.
-        * We must select an ino not used/referred by any existing inode, or
-        * 'lost+found' ino may be a missing ino in a corrupted leaf,
-        * this may cause 'lost+found' dir has wrong nlinks.
-        */
-       cache = last_cache_extent(inode_cache);
-       if (cache) {
-               node = container_of(cache, struct ptr_node, cache);
-               rec = node->data;
-               if (rec->ino > root->highest_inode)
-                       root->highest_inode = rec->ino;
-       }
-
-       /*
         * We need to repair backrefs first because we could change some of the
         * errors in the inode recs.
         *
@@ -3527,8 +3860,7 @@ static int repair_btree(struct btrfs_root *root,
                                             path.slots[level]);
 
                /* Remove the ptr */
-               ret = btrfs_del_ptr(trans, root, &path, level,
-                                   path.slots[level]);
+               ret = btrfs_del_ptr(root, &path, level, path.slots[level]);
                if (ret < 0)
                        goto out;
                /*
@@ -3536,9 +3868,9 @@ static int repair_btree(struct btrfs_root *root,
                 * return value is not concerned.
                 */
                btrfs_release_path(&path);
-               ret = btrfs_free_extent(trans, root, offset, root->nodesize,
-                                       0, root->root_key.objectid,
-                                       level - 1, 0);
+               ret = btrfs_free_extent(trans, root, offset,
+                               root->fs_info->nodesize, 0,
+                               root->root_key.objectid, level - 1, 0);
                cache = next_cache_extent(cache);
        }
 
@@ -3785,44 +4117,1210 @@ again:
                if (key.type == BTRFS_ROOT_ITEM_KEY &&
                    fs_root_objectid(key.objectid)) {
                        if (key.objectid == BTRFS_TREE_RELOC_OBJECTID) {
-                               tmp_root = btrfs_read_fs_root_no_cache(
-                                               root->fs_info, &key);
+                               tmp_root = btrfs_read_fs_root_no_cache(
+                                               root->fs_info, &key);
+                       } else {
+                               key.offset = (u64)-1;
+                               tmp_root = btrfs_read_fs_root(
+                                               root->fs_info, &key);
+                       }
+                       if (IS_ERR(tmp_root)) {
+                               err = 1;
+                               goto next;
+                       }
+                       ret = check_fs_root(tmp_root, root_cache, &wc);
+                       if (ret == -EAGAIN) {
+                               free_root_recs_tree(root_cache);
+                               btrfs_release_path(&path);
+                               goto again;
+                       }
+                       if (ret)
+                               err = 1;
+                       if (key.objectid == BTRFS_TREE_RELOC_OBJECTID)
+                               btrfs_free_fs_root(tmp_root);
+               } else if (key.type == BTRFS_ROOT_REF_KEY ||
+                          key.type == BTRFS_ROOT_BACKREF_KEY) {
+                       process_root_ref(leaf, path.slots[0], &key,
+                                        root_cache);
+               }
+next:
+               path.slots[0]++;
+       }
+out:
+       btrfs_release_path(&path);
+       if (err)
+               free_extent_cache_tree(&wc.shared);
+       if (!cache_tree_empty(&wc.shared))
+               fprintf(stderr, "warning line %d\n", __LINE__);
+
+       task_stop(ctx.info);
+
+       return err;
+}
+
+/*
+ * Find DIR_ITEM/DIR_INDEX for the given key and check it with the specified
+ * INODE_REF/INODE_EXTREF match.
+ *
+ * @root:      the root of the fs/file tree
+ * @ref_key:   the key of the INODE_REF/INODE_EXTREF
+ * @key:       the key of the DIR_ITEM/DIR_INDEX
+ * @index:     the index in the INODE_REF/INODE_EXTREF, be used to
+ *             distinguish root_dir between normal dir/file
+ * @name:      the name in the INODE_REF/INODE_EXTREF
+ * @namelen:   the length of name in the INODE_REF/INODE_EXTREF
+ * @mode:      the st_mode of INODE_ITEM
+ *
+ * Return 0 if no error occurred.
+ * Return ROOT_DIR_ERROR if found DIR_ITEM/DIR_INDEX for root_dir.
+ * Return DIR_ITEM_MISSING if couldn't find DIR_ITEM/DIR_INDEX for normal
+ * dir/file.
+ * Return DIR_ITEM_MISMATCH if INODE_REF/INODE_EXTREF and DIR_ITEM/DIR_INDEX
+ * not match for normal dir/file.
+ */
+static int find_dir_item(struct btrfs_root *root, struct btrfs_key *ref_key,
+                        struct btrfs_key *key, u64 index, char *name,
+                        u32 namelen, u32 mode)
+{
+       struct btrfs_path path;
+       struct extent_buffer *node;
+       struct btrfs_dir_item *di;
+       struct btrfs_key location;
+       char namebuf[BTRFS_NAME_LEN] = {0};
+       u32 total;
+       u32 cur = 0;
+       u32 len;
+       u32 name_len;
+       u32 data_len;
+       u8 filetype;
+       int slot;
+       int ret;
+
+       btrfs_init_path(&path);
+       ret = btrfs_search_slot(NULL, root, key, &path, 0, 0);
+       if (ret < 0) {
+               ret = DIR_ITEM_MISSING;
+               goto out;
+       }
+
+       /* Process root dir and goto out*/
+       if (index == 0) {
+               if (ret == 0) {
+                       ret = ROOT_DIR_ERROR;
+                       error(
+                       "root %llu INODE %s[%llu %llu] ROOT_DIR shouldn't have %s",
+                               root->objectid,
+                               ref_key->type == BTRFS_INODE_REF_KEY ?
+                                       "REF" : "EXTREF",
+                               ref_key->objectid, ref_key->offset,
+                               key->type == BTRFS_DIR_ITEM_KEY ?
+                                       "DIR_ITEM" : "DIR_INDEX");
+               } else {
+                       ret = 0;
+               }
+
+               goto out;
+       }
+
+       /* Process normal file/dir */
+       if (ret > 0) {
+               ret = DIR_ITEM_MISSING;
+               error(
+               "root %llu INODE %s[%llu %llu] doesn't have related %s[%llu %llu] namelen %u filename %s filetype %d",
+                       root->objectid,
+                       ref_key->type == BTRFS_INODE_REF_KEY ? "REF" : "EXTREF",
+                       ref_key->objectid, ref_key->offset,
+                       key->type == BTRFS_DIR_ITEM_KEY ?
+                               "DIR_ITEM" : "DIR_INDEX",
+                       key->objectid, key->offset, namelen, name,
+                       imode_to_type(mode));
+               goto out;
+       }
+
+       /* Check whether inode_id/filetype/name match */
+       node = path.nodes[0];
+       slot = path.slots[0];
+       di = btrfs_item_ptr(node, slot, struct btrfs_dir_item);
+       total = btrfs_item_size_nr(node, slot);
+       while (cur < total) {
+               ret = DIR_ITEM_MISMATCH;
+               name_len = btrfs_dir_name_len(node, di);
+               data_len = btrfs_dir_data_len(node, di);
+
+               btrfs_dir_item_key_to_cpu(node, di, &location);
+               if (location.objectid != ref_key->objectid ||
+                   location.type !=  BTRFS_INODE_ITEM_KEY ||
+                   location.offset != 0)
+                       goto next;
+
+               filetype = btrfs_dir_type(node, di);
+               if (imode_to_type(mode) != filetype)
+                       goto next;
+
+               if (cur + sizeof(*di) + name_len > total ||
+                   name_len > BTRFS_NAME_LEN) {
+                       warning("root %llu %s[%llu %llu] name too long %u, trimmed",
+                               root->objectid,
+                               key->type == BTRFS_DIR_ITEM_KEY ?
+                               "DIR_ITEM" : "DIR_INDEX",
+                               key->objectid, key->offset, name_len);
+
+                       if (cur + sizeof(*di) > total)
+                               break;
+                       len = min_t(u32, total - cur - sizeof(*di),
+                                   BTRFS_NAME_LEN);
+               } else {
+                       len = name_len;
+               }
+
+               read_extent_buffer(node, namebuf, (unsigned long)(di + 1), len);
+               if (len != namelen || strncmp(namebuf, name, len))
+                       goto next;
+
+               ret = 0;
+               goto out;
+next:
+               len = sizeof(*di) + name_len + data_len;
+               di = (struct btrfs_dir_item *)((char *)di + len);
+               cur += len;
+       }
+       if (ret == DIR_ITEM_MISMATCH)
+               error(
+               "root %llu INODE %s[%llu %llu] and %s[%llu %llu] mismatch namelen %u filename %s filetype %d",
+                       root->objectid,
+                       ref_key->type == BTRFS_INODE_REF_KEY ? "REF" : "EXTREF",
+                       ref_key->objectid, ref_key->offset,
+                       key->type == BTRFS_DIR_ITEM_KEY ?
+                               "DIR_ITEM" : "DIR_INDEX",
+                       key->objectid, key->offset, namelen, name,
+                       imode_to_type(mode));
+out:
+       btrfs_release_path(&path);
+       return ret;
+}
+
+/*
+ * Traverse the given INODE_REF and call find_dir_item() to find related
+ * DIR_ITEM/DIR_INDEX.
+ *
+ * @root:      the root of the fs/file tree
+ * @ref_key:   the key of the INODE_REF
+ * @refs:      the count of INODE_REF
+ * @mode:      the st_mode of INODE_ITEM
+ *
+ * Return 0 if no error occurred.
+ */
+static int check_inode_ref(struct btrfs_root *root, struct btrfs_key *ref_key,
+                          struct extent_buffer *node, int slot, u64 *refs,
+                          int mode)
+{
+       struct btrfs_key key;
+       struct btrfs_inode_ref *ref;
+       char namebuf[BTRFS_NAME_LEN] = {0};
+       u32 total;
+       u32 cur = 0;
+       u32 len;
+       u32 name_len;
+       u64 index;
+       int ret, err = 0;
+
+       ref = btrfs_item_ptr(node, slot, struct btrfs_inode_ref);
+       total = btrfs_item_size_nr(node, slot);
+
+next:
+       /* Update inode ref count */
+       (*refs)++;
+
+       index = btrfs_inode_ref_index(node, ref);
+       name_len = btrfs_inode_ref_name_len(node, ref);
+       if (cur + sizeof(*ref) + name_len > total ||
+           name_len > BTRFS_NAME_LEN) {
+               warning("root %llu INODE_REF[%llu %llu] name too long",
+                       root->objectid, ref_key->objectid, ref_key->offset);
+
+               if (total < cur + sizeof(*ref))
+                       goto out;
+               len = min_t(u32, total - cur - sizeof(*ref), BTRFS_NAME_LEN);
+       } else {
+               len = name_len;
+       }
+
+       read_extent_buffer(node, namebuf, (unsigned long)(ref + 1), len);
+
+       /* Check root dir ref name */
+       if (index == 0 && strncmp(namebuf, "..", name_len)) {
+               error("root %llu INODE_REF[%llu %llu] ROOT_DIR name shouldn't be %s",
+                     root->objectid, ref_key->objectid, ref_key->offset,
+                     namebuf);
+               err |= ROOT_DIR_ERROR;
+       }
+
+       /* Find related DIR_INDEX */
+       key.objectid = ref_key->offset;
+       key.type = BTRFS_DIR_INDEX_KEY;
+       key.offset = index;
+       ret = find_dir_item(root, ref_key, &key, index, namebuf, len, mode);
+       err |= ret;
+
+       /* Find related dir_item */
+       key.objectid = ref_key->offset;
+       key.type = BTRFS_DIR_ITEM_KEY;
+       key.offset = btrfs_name_hash(namebuf, len);
+       ret = find_dir_item(root, ref_key, &key, index, namebuf, len, mode);
+       err |= ret;
+
+       len = sizeof(*ref) + name_len;
+       ref = (struct btrfs_inode_ref *)((char *)ref + len);
+       cur += len;
+       if (cur < total)
+               goto next;
+
+out:
+       return err;
+}
+
+/*
+ * Traverse the given INODE_EXTREF and call find_dir_item() to find related
+ * DIR_ITEM/DIR_INDEX.
+ *
+ * @root:      the root of the fs/file tree
+ * @ref_key:   the key of the INODE_EXTREF
+ * @refs:      the count of INODE_EXTREF
+ * @mode:      the st_mode of INODE_ITEM
+ *
+ * Return 0 if no error occurred.
+ */
+static int check_inode_extref(struct btrfs_root *root,
+                             struct btrfs_key *ref_key,
+                             struct extent_buffer *node, int slot, u64 *refs,
+                             int mode)
+{
+       struct btrfs_key key;
+       struct btrfs_inode_extref *extref;
+       char namebuf[BTRFS_NAME_LEN] = {0};
+       u32 total;
+       u32 cur = 0;
+       u32 len;
+       u32 name_len;
+       u64 index;
+       u64 parent;
+       int ret;
+       int err = 0;
+
+       extref = btrfs_item_ptr(node, slot, struct btrfs_inode_extref);
+       total = btrfs_item_size_nr(node, slot);
+
+next:
+       /* update inode ref count */
+       (*refs)++;
+       name_len = btrfs_inode_extref_name_len(node, extref);
+       index = btrfs_inode_extref_index(node, extref);
+       parent = btrfs_inode_extref_parent(node, extref);
+       if (name_len <= BTRFS_NAME_LEN) {
+               len = name_len;
+       } else {
+               len = BTRFS_NAME_LEN;
+               warning("root %llu INODE_EXTREF[%llu %llu] name too long",
+                       root->objectid, ref_key->objectid, ref_key->offset);
+       }
+       read_extent_buffer(node, namebuf, (unsigned long)(extref + 1), len);
+
+       /* Check root dir ref name */
+       if (index == 0 && strncmp(namebuf, "..", name_len)) {
+               error("root %llu INODE_EXTREF[%llu %llu] ROOT_DIR name shouldn't be %s",
+                     root->objectid, ref_key->objectid, ref_key->offset,
+                     namebuf);
+               err |= ROOT_DIR_ERROR;
+       }
+
+       /* find related dir_index */
+       key.objectid = parent;
+       key.type = BTRFS_DIR_INDEX_KEY;
+       key.offset = index;
+       ret = find_dir_item(root, ref_key, &key, index, namebuf, len, mode);
+       err |= ret;
+
+       /* find related dir_item */
+       key.objectid = parent;
+       key.type = BTRFS_DIR_ITEM_KEY;
+       key.offset = btrfs_name_hash(namebuf, len);
+       ret = find_dir_item(root, ref_key, &key, index, namebuf, len, mode);
+       err |= ret;
+
+       len = sizeof(*extref) + name_len;
+       extref = (struct btrfs_inode_extref *)((char *)extref + len);
+       cur += len;
+
+       if (cur < total)
+               goto next;
+
+       return err;
+}
+
+/*
+ * Find INODE_REF/INODE_EXTREF for the given key and check it with the specified
+ * DIR_ITEM/DIR_INDEX match.
+ *
+ * @root:      the root of the fs/file tree
+ * @key:       the key of the INODE_REF/INODE_EXTREF
+ * @name:      the name in the INODE_REF/INODE_EXTREF
+ * @namelen:   the length of name in the INODE_REF/INODE_EXTREF
+ * @index:     the index in the INODE_REF/INODE_EXTREF, for DIR_ITEM set index
+ * to (u64)-1
+ * @ext_ref:   the EXTENDED_IREF feature
+ *
+ * Return 0 if no error occurred.
+ * Return >0 for error bitmap
+ */
+static int find_inode_ref(struct btrfs_root *root, struct btrfs_key *key,
+                         char *name, int namelen, u64 index,
+                         unsigned int ext_ref)
+{
+       struct btrfs_path path;
+       struct btrfs_inode_ref *ref;
+       struct btrfs_inode_extref *extref;
+       struct extent_buffer *node;
+       char ref_namebuf[BTRFS_NAME_LEN] = {0};
+       u32 total;
+       u32 cur = 0;
+       u32 len;
+       u32 ref_namelen;
+       u64 ref_index;
+       u64 parent;
+       u64 dir_id;
+       int slot;
+       int ret;
+
+       btrfs_init_path(&path);
+       ret = btrfs_search_slot(NULL, root, key, &path, 0, 0);
+       if (ret) {
+               ret = INODE_REF_MISSING;
+               goto extref;
+       }
+
+       node = path.nodes[0];
+       slot = path.slots[0];
+
+       ref = btrfs_item_ptr(node, slot, struct btrfs_inode_ref);
+       total = btrfs_item_size_nr(node, slot);
+
+       /* Iterate all entry of INODE_REF */
+       while (cur < total) {
+               ret = INODE_REF_MISSING;
+
+               ref_namelen = btrfs_inode_ref_name_len(node, ref);
+               ref_index = btrfs_inode_ref_index(node, ref);
+               if (index != (u64)-1 && index != ref_index)
+                       goto next_ref;
+
+               if (cur + sizeof(*ref) + ref_namelen > total ||
+                   ref_namelen > BTRFS_NAME_LEN) {
+                       warning("root %llu INODE %s[%llu %llu] name too long",
+                               root->objectid,
+                               key->type == BTRFS_INODE_REF_KEY ?
+                                       "REF" : "EXTREF",
+                               key->objectid, key->offset);
+
+                       if (cur + sizeof(*ref) > total)
+                               break;
+                       len = min_t(u32, total - cur - sizeof(*ref),
+                                   BTRFS_NAME_LEN);
+               } else {
+                       len = ref_namelen;
+               }
+
+               read_extent_buffer(node, ref_namebuf, (unsigned long)(ref + 1),
+                                  len);
+
+               if (len != namelen || strncmp(ref_namebuf, name, len))
+                       goto next_ref;
+
+               ret = 0;
+               goto out;
+next_ref:
+               len = sizeof(*ref) + ref_namelen;
+               ref = (struct btrfs_inode_ref *)((char *)ref + len);
+               cur += len;
+       }
+
+extref:
+       /* Skip if not support EXTENDED_IREF feature */
+       if (!ext_ref)
+               goto out;
+
+       btrfs_release_path(&path);
+       btrfs_init_path(&path);
+
+       dir_id = key->offset;
+       key->type = BTRFS_INODE_EXTREF_KEY;
+       key->offset = btrfs_extref_hash(dir_id, name, namelen);
+
+       ret = btrfs_search_slot(NULL, root, key, &path, 0, 0);
+       if (ret) {
+               ret = INODE_REF_MISSING;
+               goto out;
+       }
+
+       node = path.nodes[0];
+       slot = path.slots[0];
+
+       extref = btrfs_item_ptr(node, slot, struct btrfs_inode_extref);
+       cur = 0;
+       total = btrfs_item_size_nr(node, slot);
+
+       /* Iterate all entry of INODE_EXTREF */
+       while (cur < total) {
+               ret = INODE_REF_MISSING;
+
+               ref_namelen = btrfs_inode_extref_name_len(node, extref);
+               ref_index = btrfs_inode_extref_index(node, extref);
+               parent = btrfs_inode_extref_parent(node, extref);
+               if (index != (u64)-1 && index != ref_index)
+                       goto next_extref;
+
+               if (parent != dir_id)
+                       goto next_extref;
+
+               if (ref_namelen <= BTRFS_NAME_LEN) {
+                       len = ref_namelen;
+               } else {
+                       len = BTRFS_NAME_LEN;
+                       warning("root %llu INODE %s[%llu %llu] name too long",
+                               root->objectid,
+                               key->type == BTRFS_INODE_REF_KEY ?
+                                       "REF" : "EXTREF",
+                               key->objectid, key->offset);
+               }
+               read_extent_buffer(node, ref_namebuf,
+                                  (unsigned long)(extref + 1), len);
+
+               if (len != namelen || strncmp(ref_namebuf, name, len))
+                       goto next_extref;
+
+               ret = 0;
+               goto out;
+
+next_extref:
+               len = sizeof(*extref) + ref_namelen;
+               extref = (struct btrfs_inode_extref *)((char *)extref + len);
+               cur += len;
+
+       }
+out:
+       btrfs_release_path(&path);
+       return ret;
+}
+
+/*
+ * Traverse the given DIR_ITEM/DIR_INDEX and check related INODE_ITEM and
+ * call find_inode_ref() to check related INODE_REF/INODE_EXTREF.
+ *
+ * @root:      the root of the fs/file tree
+ * @key:       the key of the INODE_REF/INODE_EXTREF
+ * @size:      the st_size of the INODE_ITEM
+ * @ext_ref:   the EXTENDED_IREF feature
+ *
+ * Return 0 if no error occurred.
+ */
+static int check_dir_item(struct btrfs_root *root, struct btrfs_key *key,
+                         struct extent_buffer *node, int slot, u64 *size,
+                         unsigned int ext_ref)
+{
+       struct btrfs_dir_item *di;
+       struct btrfs_inode_item *ii;
+       struct btrfs_path path;
+       struct btrfs_key location;
+       char namebuf[BTRFS_NAME_LEN] = {0};
+       u32 total;
+       u32 cur = 0;
+       u32 len;
+       u32 name_len;
+       u32 data_len;
+       u8 filetype;
+       u32 mode;
+       u64 index;
+       int ret;
+       int err = 0;
+
+       /*
+        * For DIR_ITEM set index to (u64)-1, so that find_inode_ref
+        * ignore index check.
+        */
+       index = (key->type == BTRFS_DIR_INDEX_KEY) ? key->offset : (u64)-1;
+
+       di = btrfs_item_ptr(node, slot, struct btrfs_dir_item);
+       total = btrfs_item_size_nr(node, slot);
+
+       while (cur < total) {
+               data_len = btrfs_dir_data_len(node, di);
+               if (data_len)
+                       error("root %llu %s[%llu %llu] data_len shouldn't be %u",
+                             root->objectid, key->type == BTRFS_DIR_ITEM_KEY ?
+                             "DIR_ITEM" : "DIR_INDEX",
+                             key->objectid, key->offset, data_len);
+
+               name_len = btrfs_dir_name_len(node, di);
+               if (cur + sizeof(*di) + name_len > total ||
+                   name_len > BTRFS_NAME_LEN) {
+                       warning("root %llu %s[%llu %llu] name too long",
+                               root->objectid,
+                               key->type == BTRFS_DIR_ITEM_KEY ?
+                               "DIR_ITEM" : "DIR_INDEX",
+                               key->objectid, key->offset);
+
+                       if (cur + sizeof(*di) > total)
+                               break;
+                       len = min_t(u32, total - cur - sizeof(*di),
+                                   BTRFS_NAME_LEN);
+               } else {
+                       len = name_len;
+               }
+               (*size) += name_len;
+
+               read_extent_buffer(node, namebuf, (unsigned long)(di + 1), len);
+               filetype = btrfs_dir_type(node, di);
+
+               if (key->type == BTRFS_DIR_ITEM_KEY &&
+                   key->offset != btrfs_name_hash(namebuf, len)) {
+                       err |= -EIO;
+                       error("root %llu DIR_ITEM[%llu %llu] name %s namelen %u filetype %u mismatch with its hash, wanted %llu have %llu",
+                               root->objectid, key->objectid, key->offset,
+                               namebuf, len, filetype, key->offset,
+                               btrfs_name_hash(namebuf, len));
+               }
+
+               btrfs_init_path(&path);
+               btrfs_dir_item_key_to_cpu(node, di, &location);
+
+               /* Ignore related ROOT_ITEM check */
+               if (location.type == BTRFS_ROOT_ITEM_KEY)
+                       goto next;
+
+               /* Check relative INODE_ITEM(existence/filetype) */
+               ret = btrfs_search_slot(NULL, root, &location, &path, 0, 0);
+               if (ret) {
+                       err |= INODE_ITEM_MISSING;
+                       error("root %llu %s[%llu %llu] couldn't find relative INODE_ITEM[%llu] namelen %u filename %s filetype %x",
+                             root->objectid, key->type == BTRFS_DIR_ITEM_KEY ?
+                             "DIR_ITEM" : "DIR_INDEX", key->objectid,
+                             key->offset, location.objectid, name_len,
+                             namebuf, filetype);
+                       goto next;
+               }
+
+               ii = btrfs_item_ptr(path.nodes[0], path.slots[0],
+                                   struct btrfs_inode_item);
+               mode = btrfs_inode_mode(path.nodes[0], ii);
+
+               if (imode_to_type(mode) != filetype) {
+                       err |= INODE_ITEM_MISMATCH;
+                       error("root %llu %s[%llu %llu] relative INODE_ITEM filetype mismatch namelen %u filename %s filetype %d",
+                             root->objectid, key->type == BTRFS_DIR_ITEM_KEY ?
+                             "DIR_ITEM" : "DIR_INDEX", key->objectid,
+                             key->offset, name_len, namebuf, filetype);
+               }
+
+               /* Check relative INODE_REF/INODE_EXTREF */
+               location.type = BTRFS_INODE_REF_KEY;
+               location.offset = key->objectid;
+               ret = find_inode_ref(root, &location, namebuf, len,
+                                      index, ext_ref);
+               err |= ret;
+               if (ret & INODE_REF_MISSING)
+                       error("root %llu %s[%llu %llu] relative INODE_REF missing namelen %u filename %s filetype %d",
+                             root->objectid, key->type == BTRFS_DIR_ITEM_KEY ?
+                             "DIR_ITEM" : "DIR_INDEX", key->objectid,
+                             key->offset, name_len, namebuf, filetype);
+
+next:
+               btrfs_release_path(&path);
+               len = sizeof(*di) + name_len + data_len;
+               di = (struct btrfs_dir_item *)((char *)di + len);
+               cur += len;
+
+               if (key->type == BTRFS_DIR_INDEX_KEY && cur < total) {
+                       error("root %llu DIR_INDEX[%llu %llu] should contain only one entry",
+                             root->objectid, key->objectid, key->offset);
+                       break;
+               }
+       }
+
+       return err;
+}
+
+/*
+ * Check file extent datasum/hole, update the size of the file extents,
+ * check and update the last offset of the file extent.
+ *
+ * @root:      the root of fs/file tree.
+ * @fkey:      the key of the file extent.
+ * @nodatasum: INODE_NODATASUM feature.
+ * @size:      the sum of all EXTENT_DATA items size for this inode.
+ * @end:       the offset of the last extent.
+ *
+ * Return 0 if no error occurred.
+ */
+static int check_file_extent(struct btrfs_root *root, struct btrfs_key *fkey,
+                            struct extent_buffer *node, int slot,
+                            unsigned int nodatasum, u64 *size, u64 *end)
+{
+       struct btrfs_file_extent_item *fi;
+       u64 disk_bytenr;
+       u64 disk_num_bytes;
+       u64 extent_num_bytes;
+       u64 extent_offset;
+       u64 csum_found;         /* In byte size, sectorsize aligned */
+       u64 search_start;       /* Logical range start we search for csum */
+       u64 search_len;         /* Logical range len we search for csum */
+       unsigned int extent_type;
+       unsigned int is_hole;
+       int compressed = 0;
+       int ret;
+       int err = 0;
+
+       fi = btrfs_item_ptr(node, slot, struct btrfs_file_extent_item);
+
+       /* Check inline extent */
+       extent_type = btrfs_file_extent_type(node, fi);
+       if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
+               struct btrfs_item *e = btrfs_item_nr(slot);
+               u32 item_inline_len;
+
+               item_inline_len = btrfs_file_extent_inline_item_len(node, e);
+               extent_num_bytes = btrfs_file_extent_inline_len(node, slot, fi);
+               compressed = btrfs_file_extent_compression(node, fi);
+               if (extent_num_bytes == 0) {
+                       error(
+               "root %llu EXTENT_DATA[%llu %llu] has empty inline extent",
+                               root->objectid, fkey->objectid, fkey->offset);
+                       err |= FILE_EXTENT_ERROR;
+               }
+               if (!compressed && extent_num_bytes != item_inline_len) {
+                       error(
+               "root %llu EXTENT_DATA[%llu %llu] wrong inline size, have: %llu, expected: %u",
+                               root->objectid, fkey->objectid, fkey->offset,
+                               extent_num_bytes, item_inline_len);
+                       err |= FILE_EXTENT_ERROR;
+               }
+               *end += extent_num_bytes;
+               *size += extent_num_bytes;
+               return err;
+       }
+
+       /* Check extent type */
+       if (extent_type != BTRFS_FILE_EXTENT_REG &&
+                       extent_type != BTRFS_FILE_EXTENT_PREALLOC) {
+               err |= FILE_EXTENT_ERROR;
+               error("root %llu EXTENT_DATA[%llu %llu] type bad",
+                     root->objectid, fkey->objectid, fkey->offset);
+               return err;
+       }
+
+       /* Check REG_EXTENT/PREALLOC_EXTENT */
+       disk_bytenr = btrfs_file_extent_disk_bytenr(node, fi);
+       disk_num_bytes = btrfs_file_extent_disk_num_bytes(node, fi);
+       extent_num_bytes = btrfs_file_extent_num_bytes(node, fi);
+       extent_offset = btrfs_file_extent_offset(node, fi);
+       compressed = btrfs_file_extent_compression(node, fi);
+       is_hole = (disk_bytenr == 0) && (disk_num_bytes == 0);
+
+       /*
+        * Check EXTENT_DATA csum
+        *
+        * For plain (uncompressed) extent, we should only check the range
+        * we're referring to, as it's possible that part of prealloc extent
+        * has been written, and has csum:
+        *
+        * |<--- Original large preallocated extent A ---->|
+        * |<- Prealloc File Extent ->|<- Regular Extent ->|
+        *      No csum                         Has csum
+        *
+        * For compressed extent, we should check the whole range.
+        */
+       if (!compressed) {
+               search_start = disk_bytenr + extent_offset;
+               search_len = extent_num_bytes;
+       } else {
+               search_start = disk_bytenr;
+               search_len = disk_num_bytes;
+       }
+       ret = count_csum_range(root, search_start, search_len, &csum_found);
+       if (csum_found > 0 && nodatasum) {
+               err |= ODD_CSUM_ITEM;
+               error("root %llu EXTENT_DATA[%llu %llu] nodatasum shouldn't have datasum",
+                     root->objectid, fkey->objectid, fkey->offset);
+       } else if (extent_type == BTRFS_FILE_EXTENT_REG && !nodatasum &&
+                  !is_hole && (ret < 0 || csum_found < search_len)) {
+               err |= CSUM_ITEM_MISSING;
+               error("root %llu EXTENT_DATA[%llu %llu] csum missing, have: %llu, expected: %llu",
+                     root->objectid, fkey->objectid, fkey->offset,
+                     csum_found, search_len);
+       } else if (extent_type == BTRFS_FILE_EXTENT_PREALLOC && csum_found > 0) {
+               err |= ODD_CSUM_ITEM;
+               error("root %llu EXTENT_DATA[%llu %llu] prealloc shouldn't have csum, but has: %llu",
+                     root->objectid, fkey->objectid, fkey->offset, csum_found);
+       }
+
+       /* Check EXTENT_DATA hole */
+       if (!no_holes && *end != fkey->offset) {
+               err |= FILE_EXTENT_ERROR;
+               error("root %llu EXTENT_DATA[%llu %llu] interrupt",
+                     root->objectid, fkey->objectid, fkey->offset);
+       }
+
+       *end += extent_num_bytes;
+       if (!is_hole)
+               *size += extent_num_bytes;
+
+       return err;
+}
+
+/*
+ * Check INODE_ITEM and related ITEMs (the same inode number)
+ * 1. check link count
+ * 2. check inode ref/extref
+ * 3. check dir item/index
+ *
+ * @ext_ref:   the EXTENDED_IREF feature
+ *
+ * Return 0 if no error occurred.
+ * Return >0 for error or hit the traversal is done(by error bitmap)
+ */
+static int check_inode_item(struct btrfs_root *root, struct btrfs_path *path,
+                           unsigned int ext_ref)
+{
+       struct extent_buffer *node;
+       struct btrfs_inode_item *ii;
+       struct btrfs_key key;
+       u64 inode_id;
+       u32 mode;
+       u64 nlink;
+       u64 nbytes;
+       u64 isize;
+       u64 size = 0;
+       u64 refs = 0;
+       u64 extent_end = 0;
+       u64 extent_size = 0;
+       unsigned int dir;
+       unsigned int nodatasum;
+       int slot;
+       int ret;
+       int err = 0;
+
+       node = path->nodes[0];
+       slot = path->slots[0];
+
+       btrfs_item_key_to_cpu(node, &key, slot);
+       inode_id = key.objectid;
+
+       if (inode_id == BTRFS_ORPHAN_OBJECTID) {
+               ret = btrfs_next_item(root, path);
+               if (ret > 0)
+                       err |= LAST_ITEM;
+               return err;
+       }
+
+       ii = btrfs_item_ptr(node, slot, struct btrfs_inode_item);
+       isize = btrfs_inode_size(node, ii);
+       nbytes = btrfs_inode_nbytes(node, ii);
+       mode = btrfs_inode_mode(node, ii);
+       dir = imode_to_type(mode) == BTRFS_FT_DIR;
+       nlink = btrfs_inode_nlink(node, ii);
+       nodatasum = btrfs_inode_flags(node, ii) & BTRFS_INODE_NODATASUM;
+
+       while (1) {
+               ret = btrfs_next_item(root, path);
+               if (ret < 0) {
+                       /* out will fill 'err' rusing current statistics */
+                       goto out;
+               } else if (ret > 0) {
+                       err |= LAST_ITEM;
+                       goto out;
+               }
+
+               node = path->nodes[0];
+               slot = path->slots[0];
+               btrfs_item_key_to_cpu(node, &key, slot);
+               if (key.objectid != inode_id)
+                       goto out;
+
+               switch (key.type) {
+               case BTRFS_INODE_REF_KEY:
+                       ret = check_inode_ref(root, &key, node, slot, &refs,
+                                             mode);
+                       err |= ret;
+                       break;
+               case BTRFS_INODE_EXTREF_KEY:
+                       if (key.type == BTRFS_INODE_EXTREF_KEY && !ext_ref)
+                               warning("root %llu EXTREF[%llu %llu] isn't supported",
+                                       root->objectid, key.objectid,
+                                       key.offset);
+                       ret = check_inode_extref(root, &key, node, slot, &refs,
+                                                mode);
+                       err |= ret;
+                       break;
+               case BTRFS_DIR_ITEM_KEY:
+               case BTRFS_DIR_INDEX_KEY:
+                       if (!dir) {
+                               warning("root %llu INODE[%llu] mode %u shouldn't have DIR_INDEX[%llu %llu]",
+                                       root->objectid, inode_id,
+                                       imode_to_type(mode), key.objectid,
+                                       key.offset);
+                       }
+                       ret = check_dir_item(root, &key, node, slot, &size,
+                                            ext_ref);
+                       err |= ret;
+                       break;
+               case BTRFS_EXTENT_DATA_KEY:
+                       if (dir) {
+                               warning("root %llu DIR INODE[%llu] shouldn't EXTENT_DATA[%llu %llu]",
+                                       root->objectid, inode_id, key.objectid,
+                                       key.offset);
+                       }
+                       ret = check_file_extent(root, &key, node, slot,
+                                               nodatasum, &extent_size,
+                                               &extent_end);
+                       err |= ret;
+                       break;
+               case BTRFS_XATTR_ITEM_KEY:
+                       break;
+               default:
+                       error("ITEM[%llu %u %llu] UNKNOWN TYPE",
+                             key.objectid, key.type, key.offset);
+               }
+       }
+
+out:
+       /* verify INODE_ITEM nlink/isize/nbytes */
+       if (dir) {
+               if (nlink != 1) {
+                       err |= LINK_COUNT_ERROR;
+                       error("root %llu DIR INODE[%llu] shouldn't have more than one link(%llu)",
+                             root->objectid, inode_id, nlink);
+               }
+
+               /*
+                * Just a warning, as dir inode nbytes is just an
+                * instructive value.
+                */
+               if (!IS_ALIGNED(nbytes, root->fs_info->nodesize)) {
+                       warning("root %llu DIR INODE[%llu] nbytes should be aligned to %u",
+                               root->objectid, inode_id,
+                               root->fs_info->nodesize);
+               }
+
+               if (isize != size) {
+                       err |= ISIZE_ERROR;
+                       error("root %llu DIR INODE [%llu] size(%llu) not equal to %llu",
+                             root->objectid, inode_id, isize, size);
+               }
+       } else {
+               if (nlink != refs) {
+                       err |= LINK_COUNT_ERROR;
+                       error("root %llu INODE[%llu] nlink(%llu) not equal to inode_refs(%llu)",
+                             root->objectid, inode_id, nlink, refs);
+               } else if (!nlink) {
+                       err |= ORPHAN_ITEM;
+               }
+
+               if (!nbytes && !no_holes && extent_end < isize) {
+                       err |= NBYTES_ERROR;
+                       error("root %llu INODE[%llu] size (%llu) should have a file extent hole",
+                             root->objectid, inode_id, isize);
+               }
+
+               if (nbytes != extent_size) {
+                       err |= NBYTES_ERROR;
+                       error("root %llu INODE[%llu] nbytes(%llu) not equal to extent_size(%llu)",
+                             root->objectid, inode_id, nbytes, extent_size);
+               }
+       }
+
+       return err;
+}
+
+static int check_fs_first_inode(struct btrfs_root *root, unsigned int ext_ref)
+{
+       struct btrfs_path path;
+       struct btrfs_key key;
+       int err = 0;
+       int ret;
+
+       key.objectid = BTRFS_FIRST_FREE_OBJECTID;
+       key.type = BTRFS_INODE_ITEM_KEY;
+       key.offset = 0;
+
+       /* For root being dropped, we don't need to check first inode */
+       if (btrfs_root_refs(&root->root_item) == 0 &&
+           btrfs_disk_key_objectid(&root->root_item.drop_progress) >=
+           key.objectid)
+               return 0;
+
+       btrfs_init_path(&path);
+
+       ret = btrfs_search_slot(NULL, root, &key, &path, 0, 0);
+       if (ret < 0)
+               goto out;
+       if (ret > 0) {
+               ret = 0;
+               err |= INODE_ITEM_MISSING;
+               error("first inode item of root %llu is missing",
+                     root->objectid);
+       }
+
+       err |= check_inode_item(root, &path, ext_ref);
+       err &= ~LAST_ITEM;
+       if (err && !ret)
+               ret = -EIO;
+out:
+       btrfs_release_path(&path);
+       return ret;
+}
+
+/*
+ * Iterate all item on the tree and call check_inode_item() to check.
+ *
+ * @root:      the root of the tree to be checked.
+ * @ext_ref:   the EXTENDED_IREF feature
+ *
+ * Return 0 if no error found.
+ * Return <0 for error.
+ */
+static int check_fs_root_v2(struct btrfs_root *root, unsigned int ext_ref)
+{
+       struct btrfs_path path;
+       struct node_refs nrefs;
+       struct btrfs_root_item *root_item = &root->root_item;
+       int ret;
+       int level;
+       int err = 0;
+
+       /*
+        * We need to manually check the first inode item(256)
+        * As the following traversal function will only start from
+        * the first inode item in the leaf, if inode item(256) is missing
+        * we will just skip it forever.
+        */
+       ret = check_fs_first_inode(root, ext_ref);
+       if (ret < 0)
+               return ret;
+
+       memset(&nrefs, 0, sizeof(nrefs));
+       level = btrfs_header_level(root->node);
+       btrfs_init_path(&path);
+
+       if (btrfs_root_refs(root_item) > 0 ||
+           btrfs_disk_key_objectid(&root_item->drop_progress) == 0) {
+               path.nodes[level] = root->node;
+               path.slots[level] = 0;
+               extent_buffer_get(root->node);
+       } else {
+               struct btrfs_key key;
+
+               btrfs_disk_key_to_cpu(&key, &root_item->drop_progress);
+               level = root_item->drop_level;
+               path.lowest_level = level;
+               ret = btrfs_search_slot(NULL, root, &key, &path, 0, 0);
+               if (ret < 0)
+                       goto out;
+               ret = 0;
+       }
+
+       while (1) {
+               ret = walk_down_tree_v2(root, &path, &level, &nrefs, ext_ref);
+               err |= !!ret;
+
+               /* if ret is negative, walk shall stop */
+               if (ret < 0) {
+                       ret = err;
+                       break;
+               }
+
+               ret = walk_up_tree_v2(root, &path, &level);
+               if (ret != 0) {
+                       /* Normal exit, reset ret to err */
+                       ret = err;
+                       break;
+               }
+       }
+
+out:
+       btrfs_release_path(&path);
+       return ret;
+}
+
+/*
+ * Find the relative ref for root_ref and root_backref.
+ *
+ * @root:      the root of the root tree.
+ * @ref_key:   the key of the root ref.
+ *
+ * Return 0 if no error occurred.
+ */
+static int check_root_ref(struct btrfs_root *root, struct btrfs_key *ref_key,
+                         struct extent_buffer *node, int slot)
+{
+       struct btrfs_path path;
+       struct btrfs_key key;
+       struct btrfs_root_ref *ref;
+       struct btrfs_root_ref *backref;
+       char ref_name[BTRFS_NAME_LEN] = {0};
+       char backref_name[BTRFS_NAME_LEN] = {0};
+       u64 ref_dirid;
+       u64 ref_seq;
+       u32 ref_namelen;
+       u64 backref_dirid;
+       u64 backref_seq;
+       u32 backref_namelen;
+       u32 len;
+       int ret;
+       int err = 0;
+
+       ref = btrfs_item_ptr(node, slot, struct btrfs_root_ref);
+       ref_dirid = btrfs_root_ref_dirid(node, ref);
+       ref_seq = btrfs_root_ref_sequence(node, ref);
+       ref_namelen = btrfs_root_ref_name_len(node, ref);
+
+       if (ref_namelen <= BTRFS_NAME_LEN) {
+               len = ref_namelen;
+       } else {
+               len = BTRFS_NAME_LEN;
+               warning("%s[%llu %llu] ref_name too long",
+                       ref_key->type == BTRFS_ROOT_REF_KEY ?
+                       "ROOT_REF" : "ROOT_BACKREF", ref_key->objectid,
+                       ref_key->offset);
+       }
+       read_extent_buffer(node, ref_name, (unsigned long)(ref + 1), len);
+
+       /* Find relative root_ref */
+       key.objectid = ref_key->offset;
+       key.type = BTRFS_ROOT_BACKREF_KEY + BTRFS_ROOT_REF_KEY - ref_key->type;
+       key.offset = ref_key->objectid;
+
+       btrfs_init_path(&path);
+       ret = btrfs_search_slot(NULL, root, &key, &path, 0, 0);
+       if (ret) {
+               err |= ROOT_REF_MISSING;
+               error("%s[%llu %llu] couldn't find relative ref",
+                     ref_key->type == BTRFS_ROOT_REF_KEY ?
+                     "ROOT_REF" : "ROOT_BACKREF",
+                     ref_key->objectid, ref_key->offset);
+               goto out;
+       }
+
+       backref = btrfs_item_ptr(path.nodes[0], path.slots[0],
+                                struct btrfs_root_ref);
+       backref_dirid = btrfs_root_ref_dirid(path.nodes[0], backref);
+       backref_seq = btrfs_root_ref_sequence(path.nodes[0], backref);
+       backref_namelen = btrfs_root_ref_name_len(path.nodes[0], backref);
+
+       if (backref_namelen <= BTRFS_NAME_LEN) {
+               len = backref_namelen;
+       } else {
+               len = BTRFS_NAME_LEN;
+               warning("%s[%llu %llu] ref_name too long",
+                       key.type == BTRFS_ROOT_REF_KEY ?
+                       "ROOT_REF" : "ROOT_BACKREF",
+                       key.objectid, key.offset);
+       }
+       read_extent_buffer(path.nodes[0], backref_name,
+                          (unsigned long)(backref + 1), len);
+
+       if (ref_dirid != backref_dirid || ref_seq != backref_seq ||
+           ref_namelen != backref_namelen ||
+           strncmp(ref_name, backref_name, len)) {
+               err |= ROOT_REF_MISMATCH;
+               error("%s[%llu %llu] mismatch relative ref",
+                     ref_key->type == BTRFS_ROOT_REF_KEY ?
+                     "ROOT_REF" : "ROOT_BACKREF",
+                     ref_key->objectid, ref_key->offset);
+       }
+out:
+       btrfs_release_path(&path);
+       return err;
+}
+
+/*
+ * Check all fs/file tree in low_memory mode.
+ *
+ * 1. for fs tree root item, call check_fs_root_v2()
+ * 2. for fs tree root ref/backref, call check_root_ref()
+ *
+ * Return 0 if no error occurred.
+ */
+static int check_fs_roots_v2(struct btrfs_fs_info *fs_info)
+{
+       struct btrfs_root *tree_root = fs_info->tree_root;
+       struct btrfs_root *cur_root = NULL;
+       struct btrfs_path path;
+       struct btrfs_key key;
+       struct extent_buffer *node;
+       unsigned int ext_ref;
+       int slot;
+       int ret;
+       int err = 0;
+
+       ext_ref = btrfs_fs_incompat(fs_info, EXTENDED_IREF);
+
+       btrfs_init_path(&path);
+       key.objectid = BTRFS_FS_TREE_OBJECTID;
+       key.offset = 0;
+       key.type = BTRFS_ROOT_ITEM_KEY;
+
+       ret = btrfs_search_slot(NULL, tree_root, &key, &path, 0, 0);
+       if (ret < 0) {
+               err = ret;
+               goto out;
+       } else if (ret > 0) {
+               err = -ENOENT;
+               goto out;
+       }
+
+       while (1) {
+               node = path.nodes[0];
+               slot = path.slots[0];
+               btrfs_item_key_to_cpu(node, &key, slot);
+               if (key.objectid > BTRFS_LAST_FREE_OBJECTID)
+                       goto out;
+               if (key.type == BTRFS_ROOT_ITEM_KEY &&
+                   fs_root_objectid(key.objectid)) {
+                       if (key.objectid == BTRFS_TREE_RELOC_OBJECTID) {
+                               cur_root = btrfs_read_fs_root_no_cache(fs_info,
+                                                                      &key);
                        } else {
                                key.offset = (u64)-1;
-                               tmp_root = btrfs_read_fs_root(
-                                               root->fs_info, &key);
+                               cur_root = btrfs_read_fs_root(fs_info, &key);
                        }
-                       if (IS_ERR(tmp_root)) {
-                               err = 1;
+
+                       if (IS_ERR(cur_root)) {
+                               error("Fail to read fs/subvol tree: %lld",
+                                     key.objectid);
+                               err = -EIO;
                                goto next;
                        }
-                       ret = check_fs_root(tmp_root, root_cache, &wc);
-                       if (ret == -EAGAIN) {
-                               free_root_recs_tree(root_cache);
-                               btrfs_release_path(&path);
-                               goto again;
-                       }
-                       if (ret)
-                               err = 1;
+
+                       ret = check_fs_root_v2(cur_root, ext_ref);
+                       err |= ret;
+
                        if (key.objectid == BTRFS_TREE_RELOC_OBJECTID)
-                               btrfs_free_fs_root(tmp_root);
+                               btrfs_free_fs_root(cur_root);
                } else if (key.type == BTRFS_ROOT_REF_KEY ||
-                          key.type == BTRFS_ROOT_BACKREF_KEY) {
-                       process_root_ref(leaf, path.slots[0], &key,
-                                        root_cache);
+                               key.type == BTRFS_ROOT_BACKREF_KEY) {
+                       ret = check_root_ref(tree_root, &key, node, slot);
+                       err |= ret;
                }
 next:
-               path.slots[0]++;
+               ret = btrfs_next_item(tree_root, &path);
+               if (ret > 0)
+                       goto out;
+               if (ret < 0) {
+                       err = ret;
+                       goto out;
+               }
        }
+
 out:
        btrfs_release_path(&path);
-       if (err)
-               free_extent_cache_tree(&wc.shared);
-       if (!cache_tree_empty(&wc.shared))
-               fprintf(stderr, "warning line %d\n", __LINE__);
-
-       task_stop(ctx.info);
-
        return err;
 }
 
@@ -3953,8 +5451,7 @@ static int free_all_extent_backrefs(struct extent_record *rec)
        return 0;
 }
 
-static void free_extent_record_cache(struct btrfs_fs_info *fs_info,
-                                    struct cache_tree *extent_cache)
+static void free_extent_record_cache(struct cache_tree *extent_cache)
 {
        struct cache_extent *cache;
        struct extent_record *rec;
@@ -4153,9 +5650,7 @@ static int swap_values(struct btrfs_root *root, struct btrfs_path *path,
        return 0;
 }
 
-static int fix_key_order(struct btrfs_trans_handle *trans,
-                        struct btrfs_root *root,
-                        struct btrfs_path *path)
+static int fix_key_order(struct btrfs_root *root, struct btrfs_path *path)
 {
        struct extent_buffer *buf;
        struct btrfs_key k1, k2;
@@ -4183,8 +5678,7 @@ static int fix_key_order(struct btrfs_trans_handle *trans,
        return ret;
 }
 
-static int delete_bogus_item(struct btrfs_trans_handle *trans,
-                            struct btrfs_root *root,
+static int delete_bogus_item(struct btrfs_root *root,
                             struct btrfs_path *path,
                             struct extent_buffer *buf, int slot)
 {
@@ -4219,9 +5713,7 @@ static int delete_bogus_item(struct btrfs_trans_handle *trans,
        return 0;
 }
 
-static int fix_item_offset(struct btrfs_trans_handle *trans,
-                          struct btrfs_root *root,
-                          struct btrfs_path *path)
+static int fix_item_offset(struct btrfs_root *root, struct btrfs_path *path)
 {
        struct extent_buffer *buf;
        int i;
@@ -4238,8 +5730,7 @@ again:
                    BTRFS_LEAF_DATA_SIZE(root)) {
                        if (btrfs_item_end_nr(buf, i) >
                            BTRFS_LEAF_DATA_SIZE(root)) {
-                               ret = delete_bogus_item(trans, root, path,
-                                                       buf, i);
+                               ret = delete_bogus_item(root, path, buf, i);
                                if (!ret)
                                        goto again;
                                fprintf(stderr, "item is off the end of the "
@@ -4253,8 +5744,7 @@ again:
                           btrfs_item_offset_nr(buf, i - 1)) {
                        if (btrfs_item_end_nr(buf, i) >
                            btrfs_item_offset_nr(buf, i - 1)) {
-                               ret = delete_bogus_item(trans, root, path,
-                                                       buf, i);
+                               ret = delete_bogus_item(root, path, buf, i);
                                if (!ret)
                                        goto again;
                                fprintf(stderr, "items overlap, can't fix\n");
@@ -4346,9 +5836,9 @@ static int try_to_fix_bad_block(struct btrfs_root *root,
                        break;
                }
                if (status == BTRFS_TREE_BLOCK_BAD_KEY_ORDER)
-                       ret = fix_key_order(trans, search_root, &path);
+                       ret = fix_key_order(search_root, &path);
                else if (status == BTRFS_TREE_BLOCK_INVALID_OFFSETS)
-                       ret = fix_item_offset(trans, search_root, &path);
+                       ret = fix_item_offset(search_root, &path);
                if (ret) {
                        btrfs_commit_transaction(trans, search_root);
                        break;
@@ -4601,6 +6091,7 @@ static int add_extent_rec_nolookup(struct cache_tree *extent_cache,
        struct extent_record *rec;
        int ret = 0;
 
+       BUG_ON(tmpl->max_size == 0);
        rec = malloc(sizeof(*rec));
        if (!rec)
                return -ENOMEM;
@@ -4635,7 +6126,7 @@ static int add_extent_rec_nolookup(struct cache_tree *extent_cache,
 
        if (tmpl->metadata)
                rec->crossing_stripes = check_crossing_stripes(global_info,
-                               rec->start, global_info->tree_root->nodesize);
+                               rec->start, global_info->nodesize);
        check_extent_type(rec);
        return ret;
 }
@@ -4737,7 +6228,7 @@ static int add_extent_rec(struct cache_tree *extent_cache,
                if (tmpl->metadata)
                        rec->crossing_stripes = check_crossing_stripes(
                                        global_info, rec->start,
-                                       global_info->tree_root->nodesize);
+                                       global_info->nodesize);
                check_extent_type(rec);
                maybe_free_extent_rec(extent_cache, rec);
                return ret;
@@ -4764,6 +6255,7 @@ static int add_tree_backref(struct cache_tree *extent_cache, u64 bytenr,
                tmpl.start = bytenr;
                tmpl.nr = 1;
                tmpl.metadata = 1;
+               tmpl.max_size = 1;
 
                ret = add_extent_rec_nolookup(extent_cache, &tmpl);
                if (ret)
@@ -5151,7 +6643,7 @@ static int process_chunk_item(struct cache_tree *chunk_cache,
         * wrong onwer(3) out of chunk tree, to pass both chunk tree check
         * and owner<->key_type check.
         */
-       ret = btrfs_check_chunk_valid(global_info->tree_root, eb, chunk, slot,
+       ret = btrfs_check_chunk_valid(global_info, eb, chunk, slot,
                                      key->offset);
        if (ret < 0) {
                error("chunk(%llu, %llu) is not valid, ignore it",
@@ -5333,14 +6825,14 @@ static int process_extent_item(struct btrfs_root *root,
 
        if (key.type == BTRFS_METADATA_ITEM_KEY) {
                metadata = 1;
-               num_bytes = root->nodesize;
+               num_bytes = root->fs_info->nodesize;
        } else {
                num_bytes = key.offset;
        }
 
-       if (!IS_ALIGNED(key.objectid, root->sectorsize)) {
+       if (!IS_ALIGNED(key.objectid, root->fs_info->sectorsize)) {
                error("ignoring invalid extent, bytenr %llu is not aligned to %u",
-                     key.objectid, root->sectorsize);
+                     key.objectid, root->fs_info->sectorsize);
                return -EIO;
        }
        if (item_size < sizeof(*ei)) {
@@ -5369,14 +6861,14 @@ static int process_extent_item(struct btrfs_root *root,
                metadata = 1;
        else
                metadata = 0;
-       if (metadata && num_bytes != root->nodesize) {
+       if (metadata && num_bytes != root->fs_info->nodesize) {
                error("ignore invalid metadata extent, length %llu does not equal to %u",
-                     num_bytes, root->nodesize);
+                     num_bytes, root->fs_info->nodesize);
                return -EIO;
        }
-       if (!metadata && !IS_ALIGNED(num_bytes, root->sectorsize)) {
+       if (!metadata && !IS_ALIGNED(num_bytes, root->fs_info->sectorsize)) {
                error("ignore invalid data extent, length %llu is not aligned to %u",
-                     num_bytes, root->sectorsize);
+                     num_bytes, root->fs_info->sectorsize);
                return -EIO;
        }
 
@@ -5404,14 +6896,16 @@ static int process_extent_item(struct btrfs_root *root,
                        ret = add_tree_backref(extent_cache, key.objectid,
                                        0, offset, 0);
                        if (ret < 0)
-                               error("add_tree_backref failed: %s",
+                               error(
+                       "add_tree_backref failed (extent items tree block): %s",
                                      strerror(-ret));
                        break;
                case BTRFS_SHARED_BLOCK_REF_KEY:
                        ret = add_tree_backref(extent_cache, key.objectid,
                                        offset, 0, 0);
                        if (ret < 0)
-                               error("add_tree_backref failed: %s",
+                               error(
+                       "add_tree_backref failed (extent items shared block): %s",
                                      strerror(-ret));
                        break;
                case BTRFS_EXTENT_DATA_REF_KEY:
@@ -5455,7 +6949,7 @@ static int check_cache_range(struct btrfs_root *root,
 
        for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
                bytenr = btrfs_sb_offset(i);
-               ret = btrfs_rmap_block(&root->fs_info->mapping_tree,
+               ret = btrfs_rmap_block(root->fs_info,
                                       cache->key.objectid, bytenr, 0,
                                       &logical, &nr, &stripe_len);
                if (ret)
@@ -5582,7 +7076,7 @@ static int verify_space_cache(struct btrfs_root *root,
                        if (key.type == BTRFS_EXTENT_ITEM_KEY)
                                last = key.objectid + key.offset;
                        else
-                               last = key.objectid + root->nodesize;
+                               last = key.objectid + root->fs_info->nodesize;
                        path.slots[0]++;
                        continue;
                }
@@ -5594,7 +7088,7 @@ static int verify_space_cache(struct btrfs_root *root,
                if (key.type == BTRFS_EXTENT_ITEM_KEY)
                        last = key.objectid + key.offset;
                else
-                       last = key.objectid + root->nodesize;
+                       last = key.objectid + root->fs_info->nodesize;
                path.slots[0]++;
        }
 
@@ -5644,7 +7138,7 @@ static int check_space_cache(struct btrfs_root *root)
                start = cache->key.objectid + cache->key.offset;
                if (!cache->free_space_ctl) {
                        if (btrfs_init_free_space_ctl(cache,
-                                                     root->sectorsize)) {
+                                               root->fs_info->sectorsize)) {
                                ret = -ENOMEM;
                                break;
                        }
@@ -5652,8 +7146,7 @@ static int check_space_cache(struct btrfs_root *root)
                        btrfs_remove_free_space_cache(cache);
                }
 
-               if (btrfs_fs_compat_ro(root->fs_info,
-                                      BTRFS_FEATURE_COMPAT_RO_FREE_SPACE_TREE)) {
+               if (btrfs_fs_compat_ro(root->fs_info, FREE_SPACE_TREE)) {
                        ret = exclude_super_stripes(root, cache);
                        if (ret) {
                                fprintf(stderr, "could not exclude super stripes: %s\n",
@@ -5693,8 +7186,9 @@ static int check_extent_csums(struct btrfs_root *root, u64 bytenr,
                        u64 num_bytes, unsigned long leaf_offset,
                        struct extent_buffer *eb) {
 
+       struct btrfs_fs_info *fs_info = root->fs_info;
        u64 offset = 0;
-       u16 csum_size = btrfs_super_csum_size(root->fs_info->super_copy);
+       u16 csum_size = btrfs_super_csum_size(fs_info->super_copy);
        char *data;
        unsigned long csum_offset;
        u32 csum;
@@ -5706,7 +7200,7 @@ static int check_extent_csums(struct btrfs_root *root, u64 bytenr,
        int mirror;
        int num_copies;
 
-       if (num_bytes % root->sectorsize)
+       if (num_bytes % fs_info->sectorsize)
                return -EINVAL;
 
        data = malloc(num_bytes);
@@ -5718,7 +7212,7 @@ static int check_extent_csums(struct btrfs_root *root, u64 bytenr,
 again:
                read_len = num_bytes - offset;
                /* read as much space once a time */
-               ret = read_extent_data(root, data + offset,
+               ret = read_extent_data(fs_info, data + offset,
                                bytenr + offset, &read_len, mirror);
                if (ret)
                        goto out;
@@ -5728,12 +7222,12 @@ again:
                        csum = ~(u32)0;
                        tmp = offset + data_checked;
 
-                       csum = btrfs_csum_data(NULL, (char *)data + tmp,
-                                              csum, root->sectorsize);
+                       csum = btrfs_csum_data((char *)data + tmp,
+                                              csum, fs_info->sectorsize);
                        btrfs_csum_final(csum, (u8 *)&csum);
 
                        csum_offset = leaf_offset +
-                                tmp / root->sectorsize * csum_size;
+                                tmp / fs_info->sectorsize * csum_size;
                        read_extent_buffer(eb, (char *)&csum_expected,
                                           csum_offset, csum_size);
                        /* try another mirror */
@@ -5741,15 +7235,14 @@ again:
                                fprintf(stderr, "mirror %d bytenr %llu csum %u expected csum %u\n",
                                                mirror, bytenr + tmp,
                                                csum, csum_expected);
-                               num_copies = btrfs_num_copies(
-                                               &root->fs_info->mapping_tree,
+                               num_copies = btrfs_num_copies(root->fs_info,
                                                bytenr, num_bytes);
                                if (mirror < num_copies - 1) {
                                        mirror += 1;
                                        goto again;
                                }
                        }
-                       data_checked += root->sectorsize;
+                       data_checked += fs_info->sectorsize;
                }
                offset += read_len;
        }
@@ -5950,7 +7443,7 @@ static int check_csums(struct btrfs_root *root)
                }
 
                data_len = (btrfs_item_size_nr(leaf, path.slots[0]) /
-                             csum_size) * root->sectorsize;
+                             csum_size) * root->fs_info->sectorsize;
                if (!check_data_csum)
                        goto skip_csum_check;
                leaf_offset = btrfs_item_ptr_offset(leaf, path.slots[0]);
@@ -6015,8 +7508,7 @@ static int is_dropped_key(struct btrfs_key *key,
  * assumption and simply indicate that we _think_ that the FULL BACKREF needs to
  * be set or not and then we can check later once we've gathered all the refs.
  */
-static int calc_extent_flag(struct btrfs_root *root,
-                          struct cache_tree *extent_cache,
+static int calc_extent_flag(struct cache_tree *extent_cache,
                           struct extent_buffer *buf,
                           struct root_item_record *ri,
                           u64 *flags)
@@ -6136,6 +7628,7 @@ static int run_next_block(struct btrfs_root *root,
                          struct device_extent_tree *dev_extent_cache,
                          struct root_item_record *ri)
 {
+       struct btrfs_fs_info *fs_info = root->fs_info;
        struct extent_buffer *buf;
        struct extent_record *rec = NULL;
        u64 bytenr;
@@ -6165,7 +7658,7 @@ static int run_next_block(struct btrfs_root *root,
                                continue;
 
                        /* fixme, get the parent transid */
-                       readahead_tree_block(root, bits[i].start,
+                       readahead_tree_block(fs_info, bits[i].start,
                                             bits[i].size, 0);
                }
        }
@@ -6195,7 +7688,7 @@ static int run_next_block(struct btrfs_root *root,
        }
 
        /* fixme, get the real parent transid */
-       buf = read_tree_block(root, bytenr, size, gen);
+       buf = read_tree_block(root->fs_info, bytenr, size, gen);
        if (!extent_buffer_uptodate(buf)) {
                record_bad_block_io(root->fs_info,
                                    extent_cache, bytenr, size);
@@ -6210,7 +7703,7 @@ static int run_next_block(struct btrfs_root *root,
                                       btrfs_header_level(buf), 1, NULL,
                                       &flags);
                if (ret < 0) {
-                       ret = calc_extent_flag(root, extent_cache, buf, ri, &flags);
+                       ret = calc_extent_flag(extent_cache, buf, ri, &flags);
                        if (ret < 0) {
                                fprintf(stderr, "Couldn't calc extent flags\n");
                                flags |= BTRFS_BLOCK_FLAG_FULL_BACKREF;
@@ -6218,7 +7711,7 @@ static int run_next_block(struct btrfs_root *root,
                }
        } else {
                flags = 0;
-               ret = calc_extent_flag(root, extent_cache, buf, ri, &flags);
+               ret = calc_extent_flag(extent_cache, buf, ri, &flags);
                if (ret < 0) {
                        fprintf(stderr, "Couldn't calc extent flags\n");
                        flags |= BTRFS_BLOCK_FLAG_FULL_BACKREF;
@@ -6327,7 +7820,8 @@ static int run_next_block(struct btrfs_root *root,
                                ret = add_tree_backref(extent_cache,
                                                key.objectid, 0, key.offset, 0);
                                if (ret < 0)
-                                       error("add_tree_backref failed: %s",
+                                       error(
+                               "add_tree_backref failed (leaf tree block): %s",
                                              strerror(-ret));
                                continue;
                        }
@@ -6335,7 +7829,8 @@ static int run_next_block(struct btrfs_root *root,
                                ret = add_tree_backref(extent_cache,
                                                key.objectid, key.offset, 0, 0);
                                if (ret < 0)
-                                       error("add_tree_backref failed: %s",
+                                       error(
+                               "add_tree_backref failed (leaf shared block): %s",
                                              strerror(-ret));
                                continue;
                        }
@@ -6350,7 +7845,7 @@ static int run_next_block(struct btrfs_root *root,
                                                                       ref),
                                        btrfs_extent_data_ref_offset(buf, ref),
                                        btrfs_extent_data_ref_count(buf, ref),
-                                       0, root->sectorsize);
+                                       0, root->fs_info->sectorsize);
                                continue;
                        }
                        if (key.type == BTRFS_SHARED_DATA_REF_KEY) {
@@ -6360,7 +7855,7 @@ static int run_next_block(struct btrfs_root *root,
                                add_data_backref(extent_cache,
                                        key.objectid, key.offset, 0, 0, 0,
                                        btrfs_shared_data_ref_count(buf, ref),
-                                       0, root->sectorsize);
+                                       0, root->fs_info->sectorsize);
                                continue;
                        }
                        if (key.type == BTRFS_ORPHAN_ITEM_KEY) {
@@ -6392,7 +7887,7 @@ static int run_next_block(struct btrfs_root *root,
 
                        data_bytes_allocated +=
                                btrfs_file_extent_disk_num_bytes(buf, fi);
-                       if (data_bytes_allocated < root->sectorsize) {
+                       if (data_bytes_allocated < root->fs_info->sectorsize) {
                                abort();
                        }
                        data_bytes_referenced +=
@@ -6416,7 +7911,7 @@ static int run_next_block(struct btrfs_root *root,
                        struct extent_record tmpl;
 
                        ptr = btrfs_node_blockptr(buf, i);
-                       size = root->nodesize;
+                       size = root->fs_info->nodesize;
                        btrfs_node_key_to_cpu(buf, &key, i);
                        if (ri != NULL) {
                                if ((level == ri->drop_level)
@@ -6440,7 +7935,8 @@ static int run_next_block(struct btrfs_root *root,
                        ret = add_tree_backref(extent_cache, ptr, parent,
                                        owner, 1);
                        if (ret < 0) {
-                               error("add_tree_backref failed: %s",
+                               error(
+                               "add_tree_backref failed (non-leaf block): %s",
                                      strerror(-ret));
                                continue;
                        }
@@ -6577,7 +8073,7 @@ out:
 static int delete_extent_records(struct btrfs_trans_handle *trans,
                                 struct btrfs_root *root,
                                 struct btrfs_path *path,
-                                u64 bytenr, u64 new_len)
+                                u64 bytenr)
 {
        struct btrfs_key key;
        struct btrfs_key found_key;
@@ -6641,7 +8137,7 @@ static int delete_extent_records(struct btrfs_trans_handle *trans,
                if (found_key.type == BTRFS_EXTENT_ITEM_KEY ||
                    found_key.type == BTRFS_METADATA_ITEM_KEY) {
                        u64 bytes = (found_key.type == BTRFS_EXTENT_ITEM_KEY) ?
-                               found_key.offset : root->nodesize;
+                               found_key.offset : root->fs_info->nodesize;
 
                        ret = btrfs_update_block_group(trans, root, bytenr,
                                                       bytes, 0, 0);
@@ -6665,18 +8161,17 @@ static int record_extent(struct btrfs_trans_handle *trans,
                         struct extent_backref *back,
                         int allocated, u64 flags)
 {
-       int ret;
+       int ret = 0;
        struct btrfs_root *extent_root = info->extent_root;
        struct extent_buffer *leaf;
        struct btrfs_key ins_key;
        struct btrfs_extent_item *ei;
-       struct tree_backref *tback;
        struct data_backref *dback;
        struct btrfs_tree_block_info *bi;
 
        if (!back->is_data)
                rec->max_size = max_t(u64, rec->max_size,
-                                   info->extent_root->nodesize);
+                                   info->nodesize);
 
        if (!allocated) {
                u32 item_size = sizeof(*ei);
@@ -6706,7 +8201,6 @@ static int record_extent(struct btrfs_trans_handle *trans,
                } else {
                        struct btrfs_disk_key copy_key;;
 
-                       tback = to_tree_backref(back);
                        bi = (struct btrfs_tree_block_info *)(ei + 1);
                        memset_extent_buffer(leaf, 0, (unsigned long)bi,
                                             sizeof(*bi));
@@ -6772,6 +8266,7 @@ static int record_extent(struct btrfs_trans_handle *trans,
                                dback->found_ref);
        } else {
                u64 parent;
+               struct tree_backref *tback;
 
                tback = to_tree_backref(back);
                if (back->full_backref)
@@ -6809,11 +8304,6 @@ static struct extent_entry *find_most_right_entry(struct list_head *entries)
        struct extent_entry *entry, *best = NULL, *prev = NULL;
 
        list_for_each_entry(entry, entries, list) {
-               if (!prev) {
-                       prev = entry;
-                       continue;
-               }
-
                /*
                 * If there are as many broken entries as entries then we know
                 * not to trust this particular entry.
@@ -6822,6 +8312,16 @@ static struct extent_entry *find_most_right_entry(struct list_head *entries)
                        continue;
 
                /*
+                * Special case, when there are only two entries and 'best' is
+                * the first one
+                */
+               if (!prev) {
+                       best = entry;
+                       prev = entry;
+                       continue;
+               }
+
+               /*
                 * If our current entry == best then we can't be sure our best
                 * is really the best, so we need to keep searching.
                 */
@@ -7183,8 +8683,7 @@ out:
        return ret;
 }
 
-static int process_duplicates(struct btrfs_root *root,
-                             struct cache_tree *extent_cache,
+static int process_duplicates(struct cache_tree *extent_cache,
                              struct extent_record *rec)
 {
        struct extent_record *good, *tmp;
@@ -7579,7 +9078,7 @@ static int fixup_extent_refs(struct btrfs_fs_info *info,
 
        /* step two, delete all the existing records */
        ret = delete_extent_records(trans, info->extent_root, &path,
-                                   rec->start, rec->max_size);
+                                   rec->start);
 
        if (ret < 0)
                goto out;
@@ -7618,6 +9117,10 @@ out:
                        ret = err;
        }
 
+       if (!ret)
+               fprintf(stderr, "Repaired extent references for %llu\n",
+                               (unsigned long long)rec->start);
+
        btrfs_release_path(&path);
        return ret;
 }
@@ -7675,7 +9178,12 @@ static int fixup_extent_flags(struct btrfs_fs_info *fs_info,
        btrfs_set_extent_flags(path.nodes[0], ei, flags);
        btrfs_mark_buffer_dirty(path.nodes[0]);
        btrfs_release_path(&path);
-       return btrfs_commit_transaction(trans, root);
+       ret = btrfs_commit_transaction(trans, root);
+       if (!ret)
+               fprintf(stderr, "Repaired extent flags for %llu\n",
+                               (unsigned long long)rec->start);
+
+       return ret;
 }
 
 /* right now we only prune from the extent allocation tree */
@@ -7740,7 +9248,7 @@ again:
 
 del_ptr:
        printk("deleting pointer to block %Lu\n", corrupt->cache.start);
-       ret = btrfs_del_ptr(trans, info->extent_root, &path, level, slot);
+       ret = btrfs_del_ptr(info->extent_root, &path, level, slot);
 
 out:
        btrfs_release_path(&path);
@@ -7782,8 +9290,7 @@ static void reset_cached_block_groups(struct btrfs_fs_info *fs_info)
                                            &start, &end, EXTENT_DIRTY);
                if (ret)
                        break;
-               clear_extent_dirty(&fs_info->free_space_cache, start, end,
-                                  GFP_NOFS);
+               clear_extent_dirty(&fs_info->free_space_cache, start, end);
        }
 
        start = 0;
@@ -7802,11 +9309,8 @@ static int check_extent_refs(struct btrfs_root *root,
 {
        struct extent_record *rec;
        struct cache_extent *cache;
-       int err = 0;
        int ret = 0;
-       int fixed = 0;
        int had_dups = 0;
-       int recorded = 0;
 
        if (repair) {
                /*
@@ -7820,8 +9324,7 @@ static int check_extent_refs(struct btrfs_root *root,
                        rec = container_of(cache, struct extent_record, cache);
                        set_extent_dirty(root->fs_info->excluded_extents,
                                         rec->start,
-                                        rec->start + rec->max_size - 1,
-                                        GFP_NOFS);
+                                        rec->start + rec->max_size - 1);
                        cache = next_cache_extent(cache);
                }
 
@@ -7830,8 +9333,7 @@ static int check_extent_refs(struct btrfs_root *root,
                while(cache) {
                        set_extent_dirty(root->fs_info->excluded_extents,
                                         cache->start,
-                                        cache->start + cache->size - 1,
-                                        GFP_NOFS);
+                                        cache->start + cache->size - 1);
                        cache = next_cache_extent(cache);
                }
                prune_corrupt_blocks(root->fs_info);
@@ -7856,7 +9358,7 @@ static int check_extent_refs(struct btrfs_root *root,
                 * process_duplicates() will return 0, otherwise it will return
                 * 1 and we
                 */
-               if (process_duplicates(root, extent_cache, rec))
+               if (process_duplicates(extent_cache, rec))
                        continue;
                ret = delete_duplicate_records(root, rec);
                if (ret < 0)
@@ -7875,9 +9377,8 @@ static int check_extent_refs(struct btrfs_root *root,
 
        while(1) {
                int cur_err = 0;
+               int fix = 0;
 
-               fixed = 0;
-               recorded = 0;
                cache = search_cache_extent(extent_cache, 0);
                if (!cache)
                        break;
@@ -7885,7 +9386,6 @@ static int check_extent_refs(struct btrfs_root *root,
                if (rec->num_duplicates) {
                        fprintf(stderr, "extent item %llu has multiple extent "
                                "items\n", (unsigned long long)rec->start);
-                       err = 1;
                        cur_err = 1;
                }
 
@@ -7899,54 +9399,31 @@ static int check_extent_refs(struct btrfs_root *root,
                        ret = record_orphan_data_extents(root->fs_info, rec);
                        if (ret < 0)
                                goto repair_abort;
-                       if (ret == 0) {
-                               recorded = 1;
-                       } else {
-                               /*
-                                * we can't use the extent to repair file
-                                * extent, let the fallback method handle it.
-                                */
-                               if (!fixed && repair) {
-                                       ret = fixup_extent_refs(
-                                                       root->fs_info,
-                                                       extent_cache, rec);
-                                       if (ret)
-                                               goto repair_abort;
-                                       fixed = 1;
-                               }
-                       }
-                       err = 1;
+                       fix = ret;
                        cur_err = 1;
                }
                if (all_backpointers_checked(rec, 1)) {
                        fprintf(stderr, "backpointer mismatch on [%llu %llu]\n",
                                (unsigned long long)rec->start,
                                (unsigned long long)rec->nr);
-
-                       if (!fixed && !recorded && repair) {
-                               ret = fixup_extent_refs(root->fs_info,
-                                                       extent_cache, rec);
-                               if (ret)
-                                       goto repair_abort;
-                               fixed = 1;
-                       }
+                       fix = 1;
                        cur_err = 1;
-                       err = 1;
                }
                if (!rec->owner_ref_checked) {
                        fprintf(stderr, "owner ref check failed [%llu %llu]\n",
                                (unsigned long long)rec->start,
                                (unsigned long long)rec->nr);
-                       if (!fixed && !recorded && repair) {
-                               ret = fixup_extent_refs(root->fs_info,
-                                                       extent_cache, rec);
-                               if (ret)
-                                       goto repair_abort;
-                               fixed = 1;
-                       }
-                       err = 1;
+                       fix = 1;
                        cur_err = 1;
                }
+
+               if (repair && fix) {
+                       ret = fixup_extent_refs(root->fs_info, extent_cache, rec);
+                       if (ret)
+                               goto repair_abort;
+               }
+
+
                if (rec->bad_full_backref) {
                        fprintf(stderr, "bad full backref, on [%llu]\n",
                                (unsigned long long)rec->start);
@@ -7954,9 +9431,8 @@ static int check_extent_refs(struct btrfs_root *root,
                                ret = fixup_extent_flags(root->fs_info, rec);
                                if (ret)
                                        goto repair_abort;
-                               fixed = 1;
+                               fix = 1;
                        }
-                       err = 1;
                        cur_err = 1;
                }
                /*
@@ -7968,7 +9444,6 @@ static int check_extent_refs(struct btrfs_root *root,
                        fprintf(stderr,
                                "bad metadata [%llu, %llu) crossing stripe boundary\n",
                                rec->start, rec->start + rec->max_size);
-                       err = 1;
                        cur_err = 1;
                }
 
@@ -7976,17 +9451,15 @@ static int check_extent_refs(struct btrfs_root *root,
                        fprintf(stderr,
                                "bad extent [%llu, %llu), type mismatch with chunk\n",
                                rec->start, rec->start + rec->max_size);
-                       err = 1;
                        cur_err = 1;
                }
 
                remove_cache_extent(extent_cache, cache);
                free_all_extent_backrefs(rec);
-               if (!init_extent_tree && repair && (!cur_err || fixed))
+               if (!init_extent_tree && repair && (!cur_err || fix))
                        clear_extent_dirty(root->fs_info->excluded_extents,
                                           rec->start,
-                                          rec->start + rec->max_size - 1,
-                                          GFP_NOFS);
+                                          rec->start + rec->max_size - 1);
                free(rec);
        }
 repair_abort:
@@ -8009,11 +9482,9 @@ repair_abort:
                        if (ret)
                                goto repair_abort;
                }
-               if (err)
-                       fprintf(stderr, "repaired damaged extent references\n");
                return ret;
        }
-       return err;
+       return 0;
 }
 
 u64 calc_stripe_length(u64 type, u64 length, int num_stripes)
@@ -8330,7 +9801,7 @@ static int deal_root_from_list(struct list_head *list,
                rec = list_entry(list->next,
                                 struct root_item_record, list);
                last = 0;
-               buf = read_tree_block(root->fs_info->tree_root,
+               buf = read_tree_block(root->fs_info,
                                      rec->bytenr, rec->level_size, 0);
                if (!extent_buffer_uptodate(buf)) {
                        free_extent_buffer(buf);
@@ -8443,14 +9914,14 @@ again:
        level = btrfs_header_level(root1->node);
        ret = add_root_item_to_list(&normal_trees, root1->root_key.objectid,
                                    root1->node->start, 0, level, 0,
-                                   root1->nodesize, NULL);
+                                   root1->fs_info->nodesize, NULL);
        if (ret < 0)
                goto out;
        root1 = root->fs_info->chunk_root;
        level = btrfs_header_level(root1->node);
        ret = add_root_item_to_list(&normal_trees, root1->root_key.objectid,
                                    root1->node->start, 0, level, 0,
-                                   root1->nodesize, NULL);
+                                   root1->fs_info->nodesize, NULL);
        if (ret < 0)
                goto out;
        btrfs_init_path(&path);
@@ -8481,7 +9952,7 @@ again:
                        last_snapshot = btrfs_root_last_snapshot(&ri);
                        if (btrfs_disk_key_objectid(&ri.drop_progress) == 0) {
                                level = btrfs_root_level(&ri);
-                               level_size = root->nodesize;
+                               level_size = root->fs_info->nodesize;
                                ret = add_root_item_to_list(&normal_trees,
                                                found_key.objectid,
                                                btrfs_root_bytenr(&ri),
@@ -8491,7 +9962,7 @@ again:
                                        goto out;
                        } else {
                                level = btrfs_root_level(&ri);
-                               level_size = root->nodesize;
+                               level_size = root->fs_info->nodesize;
                                objectid = found_key.objectid;
                                btrfs_disk_key_to_cpu(&found_key,
                                                      &ri.drop_progress);
@@ -8571,6 +10042,8 @@ out:
        free_extent_cache_tree(&pending);
        free_extent_cache_tree(&reada);
        free_extent_cache_tree(&nodes);
+       free_root_item_list(&normal_trees);
+       free_root_item_list(&dropping_trees);
        return ret;
 loop:
        free_corrupt_blocks_tree(root->fs_info->corrupt_blocks);
@@ -8582,7 +10055,7 @@ loop:
        free_block_group_tree(&block_group_cache);
        free_device_cache_tree(&dev_cache);
        free_device_extent_tree(&dev_extent_cache);
-       free_extent_record_cache(root->fs_info, &extent_cache);
+       free_extent_record_cache(&extent_cache);
        free_root_item_list(&normal_trees);
        free_root_item_list(&dropping_trees);
        extent_io_tree_cleanup(&excluded_extents);
@@ -8616,17 +10089,21 @@ static int check_tree_block_ref(struct btrfs_root *root,
        int slot;
        int skinny_level;
        int type;
-       u32 nodesize = root->nodesize;
+       u32 nodesize = root->fs_info->nodesize;
        u32 item_size;
        u64 offset;
+       int tree_reloc_root = 0;
        int found_ref = 0;
        int err = 0;
        int ret;
 
+       if (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID &&
+           btrfs_header_bytenr(root->node) == bytenr)
+               tree_reloc_root = 1;
+
        btrfs_init_path(&path);
        key.objectid = bytenr;
-       if (btrfs_fs_incompat(root->fs_info,
-                             BTRFS_FEATURE_INCOMPAT_SKINNY_METADATA))
+       if (btrfs_fs_incompat(root->fs_info, SKINNY_METADATA))
                key.type = BTRFS_METADATA_ITEM_KEY;
        else
                key.type = BTRFS_EXTENT_ITEM_KEY;
@@ -8711,9 +10188,16 @@ static int check_tree_block_ref(struct btrfs_root *root,
                        (offset == root->objectid || offset == owner)) {
                        found_ref = 1;
                } else if (type == BTRFS_SHARED_BLOCK_REF_KEY) {
+                       /*
+                        * Backref of tree reloc root points to itself, no need
+                        * to check backref any more.
+                        */
+                       if (tree_reloc_root)
+                               found_ref = 1;
+                       else
                        /* Check if the backref points to valid referencer */
-                       found_ref = !check_tree_block_ref(root, NULL, offset,
-                                                         level + 1, owner);
+                               found_ref = !check_tree_block_ref(root, NULL,
+                                               offset, level + 1, owner);
                }
 
                if (found_ref)
@@ -8764,12 +10248,10 @@ static int check_extent_data_item(struct btrfs_root *root,
        struct btrfs_extent_inline_ref *iref;
        struct btrfs_extent_data_ref *dref;
        u64 owner;
-       u64 file_extent_gen;
        u64 disk_bytenr;
        u64 disk_num_bytes;
        u64 extent_num_bytes;
        u64 extent_flags;
-       u64 extent_gen;
        u32 item_size;
        unsigned long end;
        unsigned long ptr;
@@ -8781,7 +10263,6 @@ static int check_extent_data_item(struct btrfs_root *root,
 
        btrfs_item_key_to_cpu(eb, &fi_key, slot);
        fi = btrfs_item_ptr(eb, slot, struct btrfs_file_extent_item);
-       file_extent_gen = btrfs_file_extent_generation(eb, fi);
 
        /* Nothing to check for hole and inline data extents */
        if (btrfs_file_extent_type(eb, fi) == BTRFS_FILE_EXTENT_INLINE ||
@@ -8793,20 +10274,20 @@ static int check_extent_data_item(struct btrfs_root *root,
        extent_num_bytes = btrfs_file_extent_num_bytes(eb, fi);
 
        /* Check unaligned disk_num_bytes and num_bytes */
-       if (!IS_ALIGNED(disk_num_bytes, root->sectorsize)) {
+       if (!IS_ALIGNED(disk_num_bytes, root->fs_info->sectorsize)) {
                error(
 "file extent [%llu, %llu] has unaligned disk num bytes: %llu, should be aligned to %u",
                        fi_key.objectid, fi_key.offset, disk_num_bytes,
-                       root->sectorsize);
+                       root->fs_info->sectorsize);
                err |= BYTES_UNALIGNED;
        } else {
                data_bytes_allocated += disk_num_bytes;
        }
-       if (!IS_ALIGNED(extent_num_bytes, root->sectorsize)) {
+       if (!IS_ALIGNED(extent_num_bytes, root->fs_info->sectorsize)) {
                error(
 "file extent [%llu, %llu] has unaligned num bytes: %llu, should be aligned to %u",
                        fi_key.objectid, fi_key.offset, extent_num_bytes,
-                       root->sectorsize);
+                       root->fs_info->sectorsize);
                err |= BYTES_UNALIGNED;
        } else {
                data_bytes_referenced += extent_num_bytes;
@@ -8820,17 +10301,14 @@ static int check_extent_data_item(struct btrfs_root *root,
        dbref_key.offset = btrfs_file_extent_disk_num_bytes(eb, fi);
 
        ret = btrfs_search_slot(NULL, extent_root, &dbref_key, &path, 0, 0);
-       if (ret) {
-               err |= BACKREF_MISSING;
-               goto error;
-       }
+       if (ret)
+               goto out;
 
        leaf = path.nodes[0];
        slot = path.slots[0];
        ei = btrfs_item_ptr(leaf, slot, struct btrfs_extent_item);
 
        extent_flags = btrfs_extent_flags(leaf, ei);
-       extent_gen = btrfs_extent_generation(leaf, ei);
 
        if (!(extent_flags & BTRFS_EXTENT_FLAG_DATA)) {
                error(
@@ -8840,14 +10318,6 @@ static int check_extent_data_item(struct btrfs_root *root,
                err |= BACKREF_MISMATCH;
        }
 
-       if (file_extent_gen < extent_gen) {
-               error(
-"extent[%llu %llu] backref generation mismatch, wanted: <=%llu, have: %llu",
-                       disk_bytenr, disk_num_bytes, file_extent_gen,
-                       extent_gen);
-               err |= BACKREF_MISMATCH;
-       }
-
        /* Check data backref inside that extent item */
        item_size = btrfs_item_size_nr(leaf, path.slots[0]);
        iref = (struct btrfs_extent_inline_ref *)(ei + 1);
@@ -8873,11 +10343,10 @@ static int check_extent_data_item(struct btrfs_root *root,
                ptr += btrfs_extent_inline_ref_size(type);
        }
 
-       /* Didn't found inlined data backref, try EXTENT_DATA_REF_KEY */
        if (!found_dbackref) {
                btrfs_release_path(&path);
 
-               btrfs_init_path(&path);
+               /* Didn't find inlined data backref, try EXTENT_DATA_REF_KEY */
                dbref_key.objectid = btrfs_file_extent_disk_bytenr(eb, fi);
                dbref_key.type = BTRFS_EXTENT_DATA_REF_KEY;
                dbref_key.offset = hash_extent_data_ref(root->objectid,
@@ -8885,13 +10354,32 @@ static int check_extent_data_item(struct btrfs_root *root,
 
                ret = btrfs_search_slot(NULL, root->fs_info->extent_root,
                                        &dbref_key, &path, 0, 0);
-               if (!ret)
+               if (!ret) {
                        found_dbackref = 1;
+                       goto out;
+               }
+
+               btrfs_release_path(&path);
+
+               /*
+                * Neither inlined nor EXTENT_DATA_REF found, try
+                * SHARED_DATA_REF as last chance.
+                */
+               dbref_key.objectid = disk_bytenr;
+               dbref_key.type = BTRFS_SHARED_DATA_REF_KEY;
+               dbref_key.offset = eb->start;
+
+               ret = btrfs_search_slot(NULL, root->fs_info->extent_root,
+                                       &dbref_key, &path, 0, 0);
+               if (!ret) {
+                       found_dbackref = 1;
+                       goto out;
+               }
        }
 
+out:
        if (!found_dbackref)
                err |= BACKREF_MISSING;
-error:
        btrfs_release_path(&path);
        if (err & BACKREF_MISSING) {
                error("data extent[%llu %llu] backref lost",
@@ -8959,7 +10447,7 @@ static int query_tree_block_level(struct btrfs_fs_info *fs_info, u64 bytenr)
        btrfs_release_path(&path);
 
        /* Get level from tree block as an alternative source */
-       eb = read_tree_block_fs_info(fs_info, bytenr, nodesize, transid);
+       eb = read_tree_block(fs_info, bytenr, nodesize, transid);
        if (!extent_buffer_uptodate(eb)) {
                free_extent_buffer(eb);
                return -EIO;
@@ -9012,7 +10500,7 @@ static int check_tree_block_backref(struct btrfs_fs_info *fs_info, u64 root_id,
        }
 
        /* Read out the tree block to get item/node key */
-       eb = read_tree_block(root, bytenr, root->nodesize, 0);
+       eb = read_tree_block(fs_info, bytenr, root->fs_info->nodesize, 0);
        if (!extent_buffer_uptodate(eb)) {
                err |= REFERENCER_MISSING;
                free_extent_buffer(eb);
@@ -9074,6 +10562,34 @@ out:
 }
 
 /*
+ * Check if tree block @eb is tree reloc root.
+ * Return 0 if it's not or any problem happens
+ * Return 1 if it's a tree reloc root
+ */
+static int is_tree_reloc_root(struct btrfs_fs_info *fs_info,
+                                struct extent_buffer *eb)
+{
+       struct btrfs_root *tree_reloc_root;
+       struct btrfs_key key;
+       u64 bytenr = btrfs_header_bytenr(eb);
+       u64 owner = btrfs_header_owner(eb);
+       int ret = 0;
+
+       key.objectid = BTRFS_TREE_RELOC_OBJECTID;
+       key.offset = owner;
+       key.type = BTRFS_ROOT_ITEM_KEY;
+
+       tree_reloc_root = btrfs_read_fs_root_no_cache(fs_info, &key);
+       if (IS_ERR(tree_reloc_root))
+               return 0;
+
+       if (bytenr == btrfs_header_bytenr(tree_reloc_root->node))
+               ret = 1;
+       btrfs_free_fs_root(tree_reloc_root);
+       return ret;
+}
+
+/*
  * Check referencer for shared block backref
  * If level == -1, this function will resolve the level.
  */
@@ -9086,7 +10602,7 @@ static int check_shared_block_backref(struct btrfs_fs_info *fs_info,
        int found_parent = 0;
        int i;
 
-       eb = read_tree_block_fs_info(fs_info, parent, nodesize, 0);
+       eb = read_tree_block(fs_info, parent, nodesize, 0);
        if (!extent_buffer_uptodate(eb))
                goto out;
 
@@ -9095,6 +10611,13 @@ static int check_shared_block_backref(struct btrfs_fs_info *fs_info,
        if (level < 0)
                goto out;
 
+       /* It's possible it's a tree reloc root */
+       if (parent == bytenr) {
+               if (is_tree_reloc_root(fs_info, eb))
+                       found_parent = 1;
+               goto out;
+       }
+
        if (level + 1 != btrfs_header_level(eb))
                goto out;
 
@@ -9186,6 +10709,8 @@ static int check_extent_data_backref(struct btrfs_fs_info *fs_info,
                leaf = path.nodes[0];
                slot = path.slots[0];
 
+               if (slot >= btrfs_header_nritems(leaf))
+                       goto next;
                btrfs_item_key_to_cpu(leaf, &key, slot);
                if (key.objectid != objectid || key.type != BTRFS_EXTENT_DATA_KEY)
                        break;
@@ -9201,6 +10726,7 @@ static int check_extent_data_backref(struct btrfs_fs_info *fs_info,
                    offset)
                        found_count++;
 
+next:
                ret = btrfs_next_item(root, &path);
                if (ret)
                        break;
@@ -9230,7 +10756,7 @@ static int check_shared_data_backref(struct btrfs_fs_info *fs_info,
        int found_parent = 0;
        int i;
 
-       eb = read_tree_block_fs_info(fs_info, parent, nodesize, 0);
+       eb = read_tree_block(fs_info, parent, nodesize, 0);
        if (!extent_buffer_uptodate(eb))
                goto out;
 
@@ -9328,13 +10854,20 @@ static int check_extent_item(struct btrfs_fs_info *fs_info,
        }
        end = (unsigned long)ei + item_size;
 
-       if (ptr >= end) {
+next:
+       /* Reached extent item end normally */
+       if (ptr == end)
+               goto out;
+
+       /* Beyond extent item end, wrong item size */
+       if (ptr > end) {
                err |= ITEM_SIZE_MISMATCH;
+               error("extent item at bytenr %llu slot %d has wrong size",
+                       eb->start, slot);
                goto out;
        }
 
        /* Now check every backref in this extent item */
-next:
        iref = (struct btrfs_extent_inline_ref *)ptr;
        type = btrfs_extent_inline_ref_type(eb, iref);
        offset = btrfs_extent_inline_ref_offset(eb, iref);
@@ -9371,8 +10904,7 @@ next:
        }
 
        ptr += btrfs_extent_inline_ref_size(type);
-       if (ptr < end)
-               goto next;
+       goto next;
 
 out:
        return err;
@@ -9412,7 +10944,12 @@ static int check_dev_extent_item(struct btrfs_fs_info *fs_info,
 
        l = path.nodes[0];
        chunk = btrfs_item_ptr(l, path.slots[0], struct btrfs_chunk);
-       if (btrfs_chunk_length(l, chunk) != length)
+       ret = btrfs_check_chunk_valid(fs_info, l, chunk, path.slots[0],
+                                     chunk_key.offset);
+       if (ret < 0)
+               goto out;
+
+       if (btrfs_stripe_length(fs_info, l, chunk) != length)
                goto out;
 
        num_stripes = btrfs_chunk_num_stripes(l, chunk);
@@ -9473,8 +11010,10 @@ static int check_dev_item(struct btrfs_fs_info *fs_info,
 
        /* Iterate dev_extents to calculate the used space of a device */
        while (1) {
-               btrfs_item_key_to_cpu(path.nodes[0], &key, path.slots[0]);
+               if (path.slots[0] >= btrfs_header_nritems(path.nodes[0]))
+                       goto next;
 
+               btrfs_item_key_to_cpu(path.nodes[0], &key, path.slots[0]);
                if (key.objectid > dev_id)
                        break;
                if (key.type != BTRFS_DEV_EXTENT_KEY || key.objectid != dev_id)
@@ -9571,6 +11110,11 @@ static int check_block_group_item(struct btrfs_fs_info *fs_info,
        /* Iterate extent tree to account used space */
        while (1) {
                leaf = path.nodes[0];
+
+               /* Search slot can point to the last item beyond leaf nritems */
+               if (path.slots[0] >= btrfs_header_nritems(leaf))
+                       goto next;
+
                btrfs_item_key_to_cpu(leaf, &extent_key, path.slots[0]);
                if (extent_key.objectid >= bg_key.objectid + bg_key.offset)
                        break;
@@ -9643,11 +11187,10 @@ static int check_chunk_item(struct btrfs_fs_info *fs_info,
        struct btrfs_block_group_item *bi;
        struct btrfs_block_group_item bg_item;
        struct btrfs_dev_extent *ptr;
-       u32 sectorsize = btrfs_super_sectorsize(fs_info->super_copy);
        u64 length;
        u64 chunk_end;
+       u64 stripe_len;
        u64 type;
-       u64 profile;
        int num_stripes;
        u64 offset;
        u64 objectid;
@@ -9659,25 +11202,15 @@ static int check_chunk_item(struct btrfs_fs_info *fs_info,
        chunk = btrfs_item_ptr(eb, slot, struct btrfs_chunk);
        length = btrfs_chunk_length(eb, chunk);
        chunk_end = chunk_key.offset + length;
-       if (!IS_ALIGNED(length, sectorsize)) {
-               error("chunk[%llu %llu) not aligned to %u",
-                       chunk_key.offset, chunk_end, sectorsize);
-               err |= BYTES_UNALIGNED;
+       ret = btrfs_check_chunk_valid(fs_info, eb, chunk, slot,
+                                     chunk_key.offset);
+       if (ret < 0) {
+               error("chunk[%llu %llu) is invalid", chunk_key.offset,
+                       chunk_end);
+               err |= BYTES_UNALIGNED | UNKNOWN_TYPE;
                goto out;
        }
-
        type = btrfs_chunk_type(eb, chunk);
-       profile = type & BTRFS_BLOCK_GROUP_PROFILE_MASK;
-       if (!(type & BTRFS_BLOCK_GROUP_TYPE_MASK)) {
-               error("chunk[%llu %llu) has no chunk type",
-                       chunk_key.offset, chunk_end);
-               err |= UNKNOWN_TYPE;
-       }
-       if (profile && (profile & (profile - 1))) {
-               error("chunk[%llu %llu) multiple profiles detected: %llx",
-                       chunk_key.offset, chunk_end, profile);
-               err |= UNKNOWN_TYPE;
-       }
 
        bg_key.objectid = chunk_key.offset;
        bg_key.type = BTRFS_BLOCK_GROUP_ITEM_KEY;
@@ -9706,6 +11239,7 @@ static int check_chunk_item(struct btrfs_fs_info *fs_info,
        }
 
        num_stripes = btrfs_chunk_num_stripes(eb, chunk);
+       stripe_len = btrfs_stripe_length(fs_info, eb, chunk);
        for (i = 0; i < num_stripes; i++) {
                btrfs_release_path(&path);
                btrfs_init_path(&path);
@@ -9725,7 +11259,7 @@ static int check_chunk_item(struct btrfs_fs_info *fs_info,
                offset = btrfs_dev_extent_chunk_offset(leaf, ptr);
                if (objectid != chunk_key.objectid ||
                    offset != chunk_key.offset ||
-                   btrfs_dev_extent_length(leaf, ptr) != length)
+                   btrfs_dev_extent_length(leaf, ptr) != stripe_len)
                        goto not_match_dev;
                continue;
 not_match_dev:
@@ -9984,7 +11518,8 @@ static int traverse_tree_block(struct btrfs_root *root,
                 * As a btrfs tree has most 8 levels (0..7), so it's quite safe
                 * to call the function itself.
                 */
-               eb = read_tree_block(root, blocknr, root->nodesize, 0);
+               eb = read_tree_block(root->fs_info, blocknr,
+                               root->fs_info->nodesize, 0);
                if (extent_buffer_uptodate(eb)) {
                        ret = traverse_tree_block(root, eb);
                        err |= ret;
@@ -10032,7 +11567,11 @@ static int check_chunks_and_extents_v2(struct btrfs_root *root)
                        goto next;
                key.offset = (u64)-1;
 
-               cur_root = btrfs_read_fs_root(root->fs_info, &key);
+               if (key.objectid == BTRFS_TREE_RELOC_OBJECTID)
+                       cur_root = btrfs_read_fs_root_no_cache(root->fs_info,
+                                       &key);
+               else
+                       cur_root = btrfs_read_fs_root(root->fs_info, &key);
                if (IS_ERR(cur_root) || !cur_root) {
                        error("failed to read tree: %lld", key.objectid);
                        goto next;
@@ -10041,6 +11580,8 @@ static int check_chunks_and_extents_v2(struct btrfs_root *root)
                ret = traverse_tree_block(cur_root, cur_root->node);
                err |= ret;
 
+               if (key.objectid == BTRFS_TREE_RELOC_OBJECTID)
+                       btrfs_free_fs_root(cur_root);
 next:
                ret = btrfs_next_item(root1, &path);
                if (ret)
@@ -10069,7 +11610,7 @@ static int btrfs_fsck_reinit_root(struct btrfs_trans_handle *trans,
                goto init;
        }
        c = btrfs_alloc_free_block(trans, root,
-                                  root->nodesize,
+                                  root->fs_info->nodesize,
                                   root->root_key.objectid,
                                   &disk_key, level, 0, 0);
        if (IS_ERR(c)) {
@@ -10164,8 +11705,7 @@ static int pin_down_tree_blocks(struct btrfs_fs_info *fs_info,
                         * in, but for now this doesn't actually use the root so
                         * just pass in extent_root.
                         */
-                       tmp = read_tree_block(fs_info->extent_root, bytenr,
-                                             nodesize, 0);
+                       tmp = read_tree_block(fs_info, bytenr, nodesize, 0);
                        if (!extent_buffer_uptodate(tmp)) {
                                fprintf(stderr, "Error reading root block\n");
                                return -EIO;
@@ -10183,7 +11723,7 @@ static int pin_down_tree_blocks(struct btrfs_fs_info *fs_info,
                                continue;
                        }
 
-                       tmp = read_tree_block(fs_info->extent_root, bytenr,
+                       tmp = read_tree_block(fs_info, bytenr,
                                              nodesize, 0);
                        if (!extent_buffer_uptodate(tmp)) {
                                fprintf(stderr, "Error reading tree block\n");
@@ -10265,8 +11805,7 @@ static int reset_block_groups(struct btrfs_fs_info *fs_info)
                                      key.objectid, key.offset,
                                      btrfs_chunk_length(leaf, chunk));
                set_extent_dirty(&fs_info->free_space_cache, key.offset,
-                                key.offset + btrfs_chunk_length(leaf, chunk),
-                                GFP_NOFS);
+                                key.offset + btrfs_chunk_length(leaf, chunk));
                path.slots[0]++;
        }
        start = 0;
@@ -10398,7 +11937,7 @@ static int reinit_extent_tree(struct btrfs_trans_handle *trans,
         * the leaves of any fs roots and pin down the bytes for any file
         * extents we find.  Not hard but why do it if we don't have to?
         */
-       if (btrfs_fs_incompat(fs_info, BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS)) {
+       if (btrfs_fs_incompat(fs_info, MIXED_GROUPS)) {
                fprintf(stderr, "We don't support re-initing the extent tree "
                        "for mixed block groups yet, please notify a btrfs "
                        "developer you want to do this so they can add this "
@@ -10563,13 +12102,14 @@ static int populate_csum(struct btrfs_trans_handle *trans,
                         struct btrfs_root *csum_root, char *buf, u64 start,
                         u64 len)
 {
+       struct btrfs_fs_info *fs_info = csum_root->fs_info;
        u64 offset = 0;
        u64 sectorsize;
        int ret = 0;
 
        while (offset < len) {
-               sectorsize = csum_root->sectorsize;
-               ret = read_extent_data(csum_root, buf, start + offset,
+               sectorsize = fs_info->sectorsize;
+               ret = read_extent_data(fs_info, buf, start + offset,
                                       &sectorsize, 0);
                if (ret)
                        break;
@@ -10596,7 +12136,7 @@ static int fill_csum_tree_from_one_fs_root(struct btrfs_trans_handle *trans,
        int slot = 0;
        int ret = 0;
 
-       buf = malloc(cur_root->fs_info->csum_root->sectorsize);
+       buf = malloc(cur_root->fs_info->sectorsize);
        if (!buf)
                return -ENOMEM;
 
@@ -10728,7 +12268,7 @@ static int fill_csum_tree_from_extent(struct btrfs_trans_handle *trans,
                return ret;
        }
 
-       buf = malloc(csum_root->sectorsize);
+       buf = malloc(csum_root->fs_info->sectorsize);
        if (!buf) {
                btrfs_release_path(&path);
                return -ENOMEM;
@@ -10929,8 +12469,7 @@ out:
        return ret;
 }
 
-static int maybe_repair_root_item(struct btrfs_fs_info *info,
-                                 struct btrfs_path *path,
+static int maybe_repair_root_item(struct btrfs_path *path,
                                  const struct btrfs_key *root_key,
                                  const int read_only_mode)
 {
@@ -11020,7 +12559,7 @@ static int maybe_repair_root_item(struct btrfs_fs_info *info,
  */
 static int repair_root_items(struct btrfs_fs_info *info)
 {
-       struct btrfs_path *path = NULL;
+       struct btrfs_path path;
        struct btrfs_key key;
        struct extent_buffer *leaf;
        struct btrfs_trans_handle *trans = NULL;
@@ -11028,16 +12567,12 @@ static int repair_root_items(struct btrfs_fs_info *info)
        int bad_roots = 0;
        int need_trans = 0;
 
+       btrfs_init_path(&path);
+
        ret = build_roots_info_cache(info);
        if (ret)
                goto out;
 
-       path = btrfs_alloc_path();
-       if (!path) {
-               ret = -ENOMEM;
-               goto out;
-       }
-
        key.objectid = BTRFS_FIRST_FREE_OBJECTID;
        key.type = BTRFS_ROOT_ITEM_KEY;
        key.offset = 0;
@@ -11056,19 +12591,19 @@ again:
                }
        }
 
-       ret = btrfs_search_slot(trans, info->tree_root, &key, path,
+       ret = btrfs_search_slot(trans, info->tree_root, &key, &path,
                                0, trans ? 1 : 0);
        if (ret < 0)
                goto out;
-       leaf = path->nodes[0];
+       leaf = path.nodes[0];
 
        while (1) {
                struct btrfs_key found_key;
 
-               if (path->slots[0] >= btrfs_header_nritems(leaf)) {
-                       int no_more_keys = find_next_key(path, &key);
+               if (path.slots[0] >= btrfs_header_nritems(leaf)) {
+                       int no_more_keys = find_next_key(&path, &key);
 
-                       btrfs_release_path(path);
+                       btrfs_release_path(&path);
                        if (trans) {
                                ret = btrfs_commit_transaction(trans,
                                                               info->tree_root);
@@ -11082,33 +12617,32 @@ again:
                        goto again;
                }
 
-               btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
+               btrfs_item_key_to_cpu(leaf, &found_key, path.slots[0]);
 
                if (found_key.type != BTRFS_ROOT_ITEM_KEY)
                        goto next;
                if (found_key.objectid == BTRFS_TREE_RELOC_OBJECTID)
                        goto next;
 
-               ret = maybe_repair_root_item(info, path, &found_key,
-                                            trans ? 0 : 1);
+               ret = maybe_repair_root_item(&path, &found_key, trans ? 0 : 1);
                if (ret < 0)
                        goto out;
                if (ret) {
                        if (!trans && repair) {
                                need_trans = 1;
                                key = found_key;
-                               btrfs_release_path(path);
+                               btrfs_release_path(&path);
                                goto again;
                        }
                        bad_roots++;
                }
 next:
-               path->slots[0]++;
+               path.slots[0]++;
        }
        ret = 0;
 out:
        free_roots_info_cache();
-       btrfs_free_path(path);
+       btrfs_release_path(&path);
        if (trans)
                btrfs_commit_transaction(trans, info->tree_root);
        if (ret < 0)
@@ -11175,7 +12709,6 @@ const char * const cmd_check_usage[] = {
        "--chunk-root <bytenr>       use the given bytenr for the chunk tree root",
        "-p|--progress               indicate progress",
        "--clear-space-cache v1|v2   clear space cache for v1 or v2",
-       "                            NOTE: v1 support implemented",
        NULL
 };
 
@@ -11190,6 +12723,7 @@ int cmd_check(int argc, char **argv)
        u64 chunk_root_bytenr = 0;
        char uuidbuf[BTRFS_UUID_UNPARSED_SIZE];
        int ret;
+       int err = 0;
        u64 num;
        int init_csum_tree = 0;
        int readonly = 0;
@@ -11228,7 +12762,7 @@ int cmd_check(int argc, char **argv)
                        { NULL, 0, NULL, 0}
                };
 
-               c = getopt_long(argc, argv, "as:br:p", long_options, NULL);
+               c = getopt_long(argc, argv, "as:br:pEQ", long_options, NULL);
                if (c < 0)
                        break;
                switch(c) {
@@ -11297,13 +12831,16 @@ int cmd_check(int argc, char **argv)
                                }
                                break;
                        case GETOPT_VAL_CLEAR_SPACE_CACHE:
-                               if (strcmp(optarg, "v1") != 0) {
+                               if (strcmp(optarg, "v1") == 0) {
+                                       clear_space_cache = 1;
+                               } else if (strcmp(optarg, "v2") == 0) {
+                                       clear_space_cache = 2;
+                                       ctree_flags |= OPEN_CTREE_INVALIDATE_FST;
+                               } else {
                                        error(
-                       "only v1 support implmented, unrecognized value %s",
-                       optarg);
+               "invalid argument to --clear-space-cache, must be v1 or v2");
                                        exit(1);
                                }
-                               clear_space_cache = 1;
                                ctree_flags |= OPEN_CTREE_WRITES;
                                break;
                }
@@ -11336,10 +12873,12 @@ int cmd_check(int argc, char **argv)
 
        if((ret = check_mounted(argv[optind])) < 0) {
                error("could not check mount status: %s", strerror(-ret));
+               err |= !!ret;
                goto err_out;
        } else if(ret) {
                error("%s is currently mounted, aborting", argv[optind]);
                ret = -EBUSY;
+               err |= !!ret;
                goto err_out;
        }
 
@@ -11352,16 +12891,16 @@ int cmd_check(int argc, char **argv)
        if (!info) {
                error("cannot open file system");
                ret = -EIO;
+               err |= !!ret;
                goto err_out;
        }
 
        global_info = info;
        root = info->fs_root;
-       if (clear_space_cache) {
-               if (btrfs_fs_compat_ro(info,
-                               BTRFS_FEATURE_COMPAT_RO_FREE_SPACE_TREE)) {
+       if (clear_space_cache == 1) {
+               if (btrfs_fs_compat_ro(info, FREE_SPACE_TREE)) {
                        error(
-                       "free space cache v2 detected, clearing not implemented");
+               "free space cache v2 detected, use --clear-space-cache v2");
                        ret = 1;
                        goto close_out;
                }
@@ -11374,6 +12913,21 @@ int cmd_check(int argc, char **argv)
                        printf("Free space cache cleared\n");
                }
                goto close_out;
+       } else if (clear_space_cache == 2) {
+               if (!btrfs_fs_compat_ro(info, FREE_SPACE_TREE)) {
+                       printf("no free space cache v2 to clear\n");
+                       ret = 0;
+                       goto close_out;
+               }
+               printf("Clear free space cache v2\n");
+               ret = btrfs_clear_free_space_tree(info);
+               if (ret) {
+                       error("failed to clear free space cache v2: %d", ret);
+                       ret = 1;
+               } else {
+                       printf("free space cache v2 cleared\n");
+               }
+               goto close_out;
        }
 
        /*
@@ -11384,9 +12938,11 @@ int cmd_check(int argc, char **argv)
                ret = ask_user("repair mode will force to clear out log tree, are you sure?");
                if (!ret) {
                        ret = 1;
+                       err |= !!ret;
                        goto close_out;
                }
                ret = zero_log_tree(root);
+               err |= !!ret;
                if (ret) {
                        error("failed to zero log tree: %d", ret);
                        goto close_out;
@@ -11398,6 +12954,7 @@ int cmd_check(int argc, char **argv)
                printf("Print quota groups for %s\nUUID: %s\n", argv[optind],
                       uuidbuf);
                ret = qgroup_verify_all(info);
+               err |= !!ret;
                if (ret == 0)
                        report_qgroups(1);
                goto close_out;
@@ -11406,6 +12963,7 @@ int cmd_check(int argc, char **argv)
                printf("Print extent state for subvolume %llu on %s\nUUID: %s\n",
                       subvolid, argv[optind], uuidbuf);
                ret = print_extent_state(info, subvolid);
+               err |= !!ret;
                goto close_out;
        }
        printf("Checking filesystem on %s\nUUID: %s\n", argv[optind], uuidbuf);
@@ -11414,6 +12972,7 @@ int cmd_check(int argc, char **argv)
            !extent_buffer_uptodate(info->dev_root->node) ||
            !extent_buffer_uptodate(info->chunk_root->node)) {
                error("critical roots corrupted, unable to check the filesystem");
+               err |= !!ret;
                ret = -EIO;
                goto close_out;
        }
@@ -11425,12 +12984,14 @@ int cmd_check(int argc, char **argv)
                if (IS_ERR(trans)) {
                        error("error starting transaction");
                        ret = PTR_ERR(trans);
+                       err |= !!ret;
                        goto close_out;
                }
 
                if (init_extent_tree) {
                        printf("Creating a new extent tree\n");
                        ret = reinit_extent_tree(trans, info);
+                       err |= !!ret;
                        if (ret)
                                goto close_out;
                }
@@ -11442,11 +13003,13 @@ int cmd_check(int argc, char **argv)
                                error("checksum tree initialization failed: %d",
                                                ret);
                                ret = -EIO;
+                               err |= !!ret;
                                goto close_out;
                        }
 
                        ret = fill_csum_tree(trans, info->csum_root,
                                             init_extent_tree);
+                       err |= !!ret;
                        if (ret) {
                                error("checksum tree refilling failed: %d", ret);
                                return -EIO;
@@ -11457,32 +13020,40 @@ int cmd_check(int argc, char **argv)
                 * extent entries for all of the items it finds.
                 */
                ret = btrfs_commit_transaction(trans, info->extent_root);
+               err |= !!ret;
                if (ret)
                        goto close_out;
        }
        if (!extent_buffer_uptodate(info->extent_root->node)) {
                error("critical: extent_root, unable to check the filesystem");
                ret = -EIO;
+               err |= !!ret;
                goto close_out;
        }
        if (!extent_buffer_uptodate(info->csum_root->node)) {
                error("critical: csum_root, unable to check the filesystem");
                ret = -EIO;
+               err |= !!ret;
                goto close_out;
        }
 
        if (!ctx.progress_enabled)
-               printf("checking extents");
+               fprintf(stderr, "checking extents\n");
        if (check_mode == CHECK_MODE_LOWMEM)
                ret = check_chunks_and_extents_v2(root);
        else
                ret = check_chunks_and_extents(root);
+       err |= !!ret;
        if (ret)
-               printf("Errors found in extent allocation tree or chunk allocation");
+               error(
+               "errors found in extent allocation tree or chunk allocation");
 
        ret = repair_root_items(info);
-       if (ret < 0)
+       err |= !!ret;
+       if (ret < 0) {
+               error("failed to repair root items: %s", strerror(-ret));
                goto close_out;
+       }
        if (repair) {
                fprintf(stderr, "Fixed %d roots.\n", ret);
                ret = 0;
@@ -11493,18 +13064,25 @@ int cmd_check(int argc, char **argv)
                fprintf(stderr,
                        "Please run a filesystem check with the option --repair to fix them.\n");
                ret = 1;
+               err |= !!ret;
                goto close_out;
        }
 
        if (!ctx.progress_enabled) {
-               if (btrfs_fs_compat_ro(info, BTRFS_FEATURE_COMPAT_RO_FREE_SPACE_TREE))
+               if (btrfs_fs_compat_ro(info, FREE_SPACE_TREE))
                        fprintf(stderr, "checking free space tree\n");
                else
                        fprintf(stderr, "checking free space cache\n");
        }
        ret = check_space_cache(root);
-       if (ret)
+       err |= !!ret;
+       if (ret) {
+               if (btrfs_fs_compat_ro(info, FREE_SPACE_TREE))
+                       error("errors found in free space tree");
+               else
+                       error("errors found in free space cache");
                goto out;
+       }
 
        /*
         * We used to have to have these hole extents in between our real
@@ -11512,23 +13090,37 @@ int cmd_check(int argc, char **argv)
         * are no gaps in the file extents for inodes, otherwise we can just
         * ignore it when this happens.
         */
-       no_holes = btrfs_fs_incompat(root->fs_info,
-                                    BTRFS_FEATURE_INCOMPAT_NO_HOLES);
+       no_holes = btrfs_fs_incompat(root->fs_info, NO_HOLES);
        if (!ctx.progress_enabled)
                fprintf(stderr, "checking fs roots\n");
-       ret = check_fs_roots(root, &root_cache);
-       if (ret)
+       if (check_mode == CHECK_MODE_LOWMEM)
+               ret = check_fs_roots_v2(root->fs_info);
+       else
+               ret = check_fs_roots(root, &root_cache);
+       err |= !!ret;
+       if (ret) {
+               error("errors found in fs roots");
                goto out;
+       }
 
        fprintf(stderr, "checking csums\n");
        ret = check_csums(root);
-       if (ret)
+       err |= !!ret;
+       if (ret) {
+               error("errors found in csum tree");
                goto out;
+       }
 
        fprintf(stderr, "checking root refs\n");
-       ret = check_root_refs(root, &root_cache);
-       if (ret)
-               goto out;
+       /* For low memory mode, check_fs_roots_v2 handles root refs */
+       if (check_mode != CHECK_MODE_LOWMEM) {
+               ret = check_root_refs(root, &root_cache);
+               err |= !!ret;
+               if (ret) {
+                       error("errors found in root refs");
+                       goto out;
+               }
+       }
 
        while (repair && !list_empty(&root->fs_info->recow_ebs)) {
                struct extent_buffer *eb;
@@ -11537,8 +13129,11 @@ int cmd_check(int argc, char **argv)
                                      struct extent_buffer, recow);
                list_del_init(&eb->recow);
                ret = recow_extent_buffer(root, eb);
-               if (ret)
+               err |= !!ret;
+               if (ret) {
+                       error("fails to fix transid errors");
                        break;
+               }
        }
 
        while (!list_empty(&delete_items)) {
@@ -11546,32 +13141,37 @@ int cmd_check(int argc, char **argv)
 
                bad = list_first_entry(&delete_items, struct bad_item, list);
                list_del_init(&bad->list);
-               if (repair)
+               if (repair) {
                        ret = delete_bad_item(root, bad);
+                       err |= !!ret;
+               }
                free(bad);
        }
 
        if (info->quota_enabled) {
-               int err;
                fprintf(stderr, "checking quota groups\n");
-               err = qgroup_verify_all(info);
-               if (err)
+               ret = qgroup_verify_all(info);
+               err |= !!ret;
+               if (ret) {
+                       error("failed to check quota groups");
                        goto out;
+               }
                report_qgroups(0);
-               err = repair_qgroups(info, &qgroups_repaired);
-               if (err)
+               ret = repair_qgroups(info, &qgroups_repaired);
+               err |= !!ret;
+               if (err) {
+                       error("failed to repair quota groups");
                        goto out;
+               }
+               ret = 0;
        }
 
        if (!list_empty(&root->fs_info->recow_ebs)) {
                error("transid errors in file system");
                ret = 1;
+               err |= !!ret;
        }
 out:
-       /* Don't override original ret */
-       if (!ret && qgroups_repaired)
-               ret = qgroups_repaired;
-
        if (found_old_backref) { /*
                 * there was a disk format change when mixed
                 * backref was in testing tree. The old format
@@ -11581,10 +13181,14 @@ out:
                       "The old format is not supported! *"
                       "\n * Please mount the FS in readonly mode, "
                       "backup data and re-format the FS. *\n\n");
-               ret = 1;
+               err |= 1;
        }
-       printf("found %llu bytes used err is %d\n",
-              (unsigned long long)bytes_used, ret);
+       printf("found %llu bytes used, ",
+              (unsigned long long)bytes_used);
+       if (err)
+               printf("error(s) found\n");
+       else
+               printf("no error found\n");
        printf("total csum bytes: %llu\n",(unsigned long long)total_csum_bytes);
        printf("total tree bytes: %llu\n",
               (unsigned long long)total_btree_bytes);
@@ -11606,5 +13210,5 @@ err_out:
        if (ctx.progress_enabled)
                task_deinit(ctx.info);
 
-       return ret;
+       return err;
 }