18 files changed, 535 insertions, 231 deletions

diff --git a/fs/btrfs/backref.c b/fs/btrfs/backref.c
index 3f75895c919b..7301cdb4b2cb 100644
--- a/fs/btrfs/backref.c
+++ b/fs/btrfs/backref.c
@@ -179,60 +179,74 @@ static int __add_prelim_ref(struct list_head *head, u64 root_id,
 
 static int add_all_parents(struct btrfs_root *root, struct btrfs_path *path,
                                 struct ulist *parents, int level,
-                                struct btrfs_key *key, u64 wanted_disk_byte,
+                                struct btrfs_key *key_for_search, u64 time_seq,
+                                u64 wanted_disk_byte,
                                 const u64 *extent_item_pos)
 {
-        int ret;
-        int slot = path->slots[level];
-        struct extent_buffer *eb = path->nodes[level];
+        int ret = 0;
+        int slot;
+        struct extent_buffer *eb;
+        struct btrfs_key key;
         struct btrfs_file_extent_item *fi;
         struct extent_inode_elem *eie = NULL;
         u64 disk_byte;
-        u64 wanted_objectid = key->objectid;
 
-add_parent:
-        if (level == 0 && extent_item_pos) {
-                fi = btrfs_item_ptr(eb, slot, struct btrfs_file_extent_item);
-                ret = check_extent_in_eb(key, eb, fi, *extent_item_pos, &eie);
+        if (level != 0) {
+                eb = path->nodes[level];
+                ret = ulist_add(parents, eb->start, 0, GFP_NOFS);
                 if (ret < 0)
                         return ret;
-        }
-        ret = ulist_add(parents, eb->start, (unsigned long)eie, GFP_NOFS);
-        if (ret < 0)
-                return ret;
-
-        if (level != 0)
                 return 0;
+        }
 
         /*
-         * if the current leaf is full with EXTENT_DATA items, we must
-         * check the next one if that holds a reference as well.
-         * ref->count cannot be used to skip this check.
-         * repeat this until we don't find any additional EXTENT_DATA items.
+         * We normally enter this function with the path already pointing to
+         * the first item to check. But sometimes, we may enter it with
+         * slot==nritems. In that case, go to the next leaf before we continue.
          */
-        while (1) {
-                eie = NULL;
-                ret = btrfs_next_leaf(root, path);
-                if (ret < 0)
-                        return ret;
-                if (ret)
-                        return 0;
+        if (path->slots[0] >= btrfs_header_nritems(path->nodes[0]))
+                ret = btrfs_next_old_leaf(root, path, time_seq);
 
+        while (!ret) {
                 eb = path->nodes[0];
-                for (slot = 0; slot < btrfs_header_nritems(eb); ++slot) {
-                        btrfs_item_key_to_cpu(eb, key, slot);
-                        if (key->objectid != wanted_objectid ||
-                            key->type != BTRFS_EXTENT_DATA_KEY)
-                                return 0;
-                        fi = btrfs_item_ptr(eb, slot,
-                                                struct btrfs_file_extent_item);
-                        disk_byte = btrfs_file_extent_disk_bytenr(eb, fi);
-                        if (disk_byte == wanted_disk_byte)
-                                goto add_parent;
+                slot = path->slots[0];
+
+                btrfs_item_key_to_cpu(eb, &key, slot);
+
+                if (key.objectid != key_for_search->objectid ||
+                    key.type != BTRFS_EXTENT_DATA_KEY)
+                        break;
+
+                fi = btrfs_item_ptr(eb, slot, struct btrfs_file_extent_item);
+                disk_byte = btrfs_file_extent_disk_bytenr(eb, fi);
+
+                if (disk_byte == wanted_disk_byte) {
+                        eie = NULL;
+                        if (extent_item_pos) {
+                                ret = check_extent_in_eb(&key, eb, fi,
+                                                *extent_item_pos,
+                                                &eie);
+                                if (ret < 0)
+                                        break;
+                        }
+                        if (!ret) {
+                                ret = ulist_add(parents, eb->start,
+                                                (unsigned long)eie, GFP_NOFS);
+                                if (ret < 0)
+                                        break;
+                                if (!extent_item_pos) {
+                                        ret = btrfs_next_old_leaf(root, path,
+                                                        time_seq);
+                                        continue;
+                                }
+                        }
                 }
+                ret = btrfs_next_old_item(root, path, time_seq);
         }
 
-        return 0;
+        if (ret > 0)
+                ret = 0;
+        return ret;
 }
 
 /*
@@ -249,7 +263,6 @@ static int __resolve_indirect_ref(struct btrfs_fs_info *fs_info,
         struct btrfs_path *path;
         struct btrfs_root *root;
         struct btrfs_key root_key;
-        struct btrfs_key key = {0};
         struct extent_buffer *eb;
         int ret = 0;
         int root_level;
@@ -294,19 +307,9 @@ static int __resolve_indirect_ref(struct btrfs_fs_info *fs_info,
                 goto out;
         }
 
-        if (level == 0) {
-                if (ret == 1 && path->slots[0] >= btrfs_header_nritems(eb)) {
-                        ret = btrfs_next_leaf(root, path);
-                        if (ret)
-                                goto out;
-                        eb = path->nodes[0];
-                }
-
-                btrfs_item_key_to_cpu(eb, &key, path->slots[0]);
-        }
-
-        ret = add_all_parents(root, path, parents, level, &key,
-                                ref->wanted_disk_byte, extent_item_pos);
+        ret = add_all_parents(root, path, parents, level, &ref->key_for_search,
+                                time_seq, ref->wanted_disk_byte,
+                                extent_item_pos);
 out:
         btrfs_free_path(path);
         return ret;
diff --git a/fs/btrfs/btrfs_inode.h b/fs/btrfs/btrfs_inode.h
index e616f8872e69..12394a90d60f 100644
--- a/fs/btrfs/btrfs_inode.h
+++ b/fs/btrfs/btrfs_inode.h
@@ -37,6 +37,7 @@
 #define BTRFS_INODE_IN_DEFRAG                   3
 #define BTRFS_INODE_DELALLOC_META_RESERVED      4
 #define BTRFS_INODE_HAS_ORPHAN_ITEM             5
+#define BTRFS_INODE_HAS_ASYNC_EXTENT            6
 
 /* in memory btrfs inode */
 struct btrfs_inode {
diff --git a/fs/btrfs/check-integrity.c b/fs/btrfs/check-integrity.c
index 9cebb1fd6a3c..da6e9364a5e3 100644
--- a/fs/btrfs/check-integrity.c
+++ b/fs/btrfs/check-integrity.c
@@ -93,6 +93,7 @@
 #include "print-tree.h"
 #include "locking.h"
 #include "check-integrity.h"
+#include "rcu-string.h"
 
 #define BTRFSIC_BLOCK_HASHTABLE_SIZE 0x10000
 #define BTRFSIC_BLOCK_LINK_HASHTABLE_SIZE 0x10000
@@ -843,13 +844,14 @@ static int btrfsic_process_superblock_dev_mirror(
                 superblock_tmp->never_written = 0;
                 superblock_tmp->mirror_num = 1 + superblock_mirror_num;
                 if (state->print_mask & BTRFSIC_PRINT_MASK_SUPERBLOCK_WRITE)
-                        printk(KERN_INFO "New initial S-block (bdev %p, %s)"
-                               " @%llu (%s/%llu/%d)\n",
-                               superblock_bdev, device->name,
-                               (unsigned long long)dev_bytenr,
-                               dev_state->name,
-                               (unsigned long long)dev_bytenr,
-                               superblock_mirror_num);
+                        printk_in_rcu(KERN_INFO "New initial S-block (bdev %p, %s)"
+                                     " @%llu (%s/%llu/%d)\n",
+                                     superblock_bdev,
+                                     rcu_str_deref(device->name),
+                                     (unsigned long long)dev_bytenr,
+                                     dev_state->name,
+                                     (unsigned long long)dev_bytenr,
+                                     superblock_mirror_num);
                 list_add(&superblock_tmp->all_blocks_node,
                          &state->all_blocks_list);
                 btrfsic_block_hashtable_add(superblock_tmp,
diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index d7a96cfdc50a..15cbc2bf4ff0 100644
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -467,6 +467,15 @@ static inline int tree_mod_dont_log(struct btrfs_fs_info *fs_info,
         return 0;
 }
 
+/*
+ * This allocates memory and gets a tree modification sequence number when
+ * needed.
+ *
+ * Returns 0 when no sequence number is needed, < 0 on error.
+ * Returns 1 when a sequence number was added. In this case,
+ * fs_info->tree_mod_seq_lock was acquired and must be released by the caller
+ * after inserting into the rb tree.
+ */
 static inline int tree_mod_alloc(struct btrfs_fs_info *fs_info, gfp_t flags,
                                  struct tree_mod_elem **tm_ret)
 {
@@ -491,11 +500,11 @@ static inline int tree_mod_alloc(struct btrfs_fs_info *fs_info, gfp_t flags,
                  */
                 kfree(tm);
                 seq = 0;
+                spin_unlock(&fs_info->tree_mod_seq_lock);
         } else {
                 __get_tree_mod_seq(fs_info, &tm->elem);
                 seq = tm->elem.seq;
         }
-        spin_unlock(&fs_info->tree_mod_seq_lock);
 
         return seq;
 }
@@ -521,7 +530,9 @@ tree_mod_log_insert_key_mask(struct btrfs_fs_info *fs_info,
         tm->slot = slot;
         tm->generation = btrfs_node_ptr_generation(eb, slot);
 
-        return __tree_mod_log_insert(fs_info, tm);
+        ret = __tree_mod_log_insert(fs_info, tm);
+        spin_unlock(&fs_info->tree_mod_seq_lock);
+        return ret;
 }
 
 static noinline int
@@ -559,7 +570,9 @@ tree_mod_log_insert_move(struct btrfs_fs_info *fs_info,
         tm->move.nr_items = nr_items;
         tm->op = MOD_LOG_MOVE_KEYS;
 
-        return __tree_mod_log_insert(fs_info, tm);
+        ret = __tree_mod_log_insert(fs_info, tm);
+        spin_unlock(&fs_info->tree_mod_seq_lock);
+        return ret;
 }
 
 static noinline int
@@ -580,7 +593,9 @@ tree_mod_log_insert_root(struct btrfs_fs_info *fs_info,
         tm->generation = btrfs_header_generation(old_root);
         tm->op = MOD_LOG_ROOT_REPLACE;
 
-        return __tree_mod_log_insert(fs_info, tm);
+        ret = __tree_mod_log_insert(fs_info, tm);
+        spin_unlock(&fs_info->tree_mod_seq_lock);
+        return ret;
 }
 
 static struct tree_mod_elem *
@@ -1023,6 +1038,10 @@ __tree_mod_log_oldest_root(struct btrfs_fs_info *fs_info,
                 looped = 1;
         }
 
+        /* if there's no old root to return, return what we found instead */
+        if (!found)
+                found = tm;
+
         return found;
 }
 
@@ -1143,22 +1162,36 @@ tree_mod_log_rewind(struct btrfs_fs_info *fs_info, struct extent_buffer *eb,
         return eb_rewin;
 }
 
+/*
+ * get_old_root() rewinds the state of @root's root node to the given @time_seq
+ * value. If there are no changes, the current root->root_node is returned. If
+ * anything changed in between, there's a fresh buffer allocated on which the
+ * rewind operations are done. In any case, the returned buffer is read locked.
+ * Returns NULL on error (with no locks held).
+ */
 static inline struct extent_buffer *
 get_old_root(struct btrfs_root *root, u64 time_seq)
 {
         struct tree_mod_elem *tm;
         struct extent_buffer *eb;
-        struct tree_mod_root *old_root;
-        u64 old_generation;
+        struct tree_mod_root *old_root = NULL;
+        u64 old_generation = 0;
+        u64 logical;
 
+        eb = btrfs_read_lock_root_node(root);
         tm = __tree_mod_log_oldest_root(root->fs_info, root, time_seq);
         if (!tm)
                 return root->node;
 
-        old_root = &tm->old_root;
-        old_generation = tm->generation;
+        if (tm->op == MOD_LOG_ROOT_REPLACE) {
+                old_root = &tm->old_root;
+                old_generation = tm->generation;
+                logical = old_root->logical;
+        } else {
+                logical = root->node->start;
+        }
 
-        tm = tree_mod_log_search(root->fs_info, old_root->logical, time_seq);
+        tm = tree_mod_log_search(root->fs_info, logical, time_seq);
         /*
          * there was an item in the log when __tree_mod_log_oldest_root
          * returned. this one must not go away, because the time_seq passed to
@@ -1166,22 +1199,25 @@ get_old_root(struct btrfs_root *root, u64 time_seq)
          */
         BUG_ON(!tm);
 
-        if (old_root->logical == root->node->start) {
-                /* there are logged operations for the current root */
-                eb = btrfs_clone_extent_buffer(root->node);
-        } else {
-                /* there's a root replace operation for the current root */
+        if (old_root)
                 eb = alloc_dummy_extent_buffer(tm->index << PAGE_CACHE_SHIFT,
                                                root->nodesize);
+        else
+                eb = btrfs_clone_extent_buffer(root->node);
+        btrfs_tree_read_unlock(root->node);
+        free_extent_buffer(root->node);
+        if (!eb)
+                return NULL;
+        btrfs_tree_read_lock(eb);
+        if (old_root) {
                 btrfs_set_header_bytenr(eb, eb->start);
                 btrfs_set_header_backref_rev(eb, BTRFS_MIXED_BACKREF_REV);
                 btrfs_set_header_owner(eb, root->root_key.objectid);
+                btrfs_set_header_level(eb, old_root->level);
+                btrfs_set_header_generation(eb, old_generation);
         }
-        if (!eb)
-                return NULL;
-        btrfs_set_header_level(eb, old_root->level);
-        btrfs_set_header_generation(eb, old_generation);
         __tree_mod_log_rewind(eb, time_seq, tm);
+        extent_buffer_get(eb);
 
         return eb;
 }
@@ -1650,8 +1686,6 @@ static noinline int balance_level(struct btrfs_trans_handle *trans,
             BTRFS_NODEPTRS_PER_BLOCK(root) / 4)
                 return 0;
 
-        btrfs_header_nritems(mid);
-
         left = read_node_slot(root, parent, pslot - 1);
         if (left) {
                 btrfs_tree_lock(left);
@@ -1681,7 +1715,6 @@ static noinline int balance_level(struct btrfs_trans_handle *trans,
                 wret = push_node_left(trans, root, left, mid, 1);
                 if (wret < 0)
                         ret = wret;
-                btrfs_header_nritems(mid);
         }
 
         /*
@@ -2615,9 +2648,7 @@ int btrfs_search_old_slot(struct btrfs_root *root, struct btrfs_key *key,
 
 again:
         b = get_old_root(root, time_seq);
-        extent_buffer_get(b);
         level = btrfs_header_level(b);
-        btrfs_tree_read_lock(b);
         p->locks[level] = BTRFS_READ_LOCK;
 
         while (b) {
@@ -5001,6 +5032,12 @@ next:
  */
 int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path)
 {
+        return btrfs_next_old_leaf(root, path, 0);
+}
+
+int btrfs_next_old_leaf(struct btrfs_root *root, struct btrfs_path *path,
+                        u64 time_seq)
+{
         int slot;
         int level;
         struct extent_buffer *c;
@@ -5025,7 +5062,10 @@ again:
         path->keep_locks = 1;
         path->leave_spinning = 1;
 
-        ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
+        if (time_seq)
+                ret = btrfs_search_old_slot(root, &key, path, time_seq);
+        else
+                ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
         path->keep_locks = 0;
 
         if (ret < 0)
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 0236d03c6732..fa5c45b39075 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -2753,13 +2753,20 @@ static inline int btrfs_insert_empty_item(struct btrfs_trans_handle *trans,
 }
 
 int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path);
-static inline int btrfs_next_item(struct btrfs_root *root, struct btrfs_path *p)
+int btrfs_next_old_leaf(struct btrfs_root *root, struct btrfs_path *path,
+                        u64 time_seq);
+static inline int btrfs_next_old_item(struct btrfs_root *root,
+                                      struct btrfs_path *p, u64 time_seq)
 {
         ++p->slots[0];
         if (p->slots[0] >= btrfs_header_nritems(p->nodes[0]))
-                return btrfs_next_leaf(root, p);
+                return btrfs_next_old_leaf(root, p, time_seq);
         return 0;
 }
+static inline int btrfs_next_item(struct btrfs_root *root, struct btrfs_path *p)
+{
+        return btrfs_next_old_item(root, p, 0);
+}
 int btrfs_prev_leaf(struct btrfs_root *root, struct btrfs_path *path);
 int btrfs_leaf_free_space(struct btrfs_root *root, struct extent_buffer *leaf);
 int __must_check btrfs_drop_snapshot(struct btrfs_root *root,
diff --git a/fs/btrfs/delayed-inode.c b/fs/btrfs/delayed-inode.c
index c18d0442ae6d..2399f4086915 100644
--- a/fs/btrfs/delayed-inode.c
+++ b/fs/btrfs/delayed-inode.c
@@ -1879,3 +1879,21 @@ void btrfs_kill_all_delayed_nodes(struct btrfs_root *root)
                 }
         }
 }
+
+void btrfs_destroy_delayed_inodes(struct btrfs_root *root)
+{
+        struct btrfs_delayed_root *delayed_root;
+        struct btrfs_delayed_node *curr_node, *prev_node;
+
+        delayed_root = btrfs_get_delayed_root(root);
+
+        curr_node = btrfs_first_delayed_node(delayed_root);
+        while (curr_node) {
+                __btrfs_kill_delayed_node(curr_node);
+
+                prev_node = curr_node;
+                curr_node = btrfs_next_delayed_node(curr_node);
+                btrfs_release_delayed_node(prev_node);
+        }
+}
+
diff --git a/fs/btrfs/delayed-inode.h b/fs/btrfs/delayed-inode.h
index 7083d08b2a21..f5aa4023d3e1 100644
--- a/fs/btrfs/delayed-inode.h
+++ b/fs/btrfs/delayed-inode.h
@@ -124,6 +124,9 @@ int btrfs_fill_inode(struct inode *inode, u32 *rdev);
 /* Used for drop dead root */
 void btrfs_kill_all_delayed_nodes(struct btrfs_root *root);
 
+/* Used for clean the transaction */
+void btrfs_destroy_delayed_inodes(struct btrfs_root *root);
+
 /* Used for readdir() */
 void btrfs_get_delayed_items(struct inode *inode, struct list_head *ins_list,
                              struct list_head *del_list);
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 7ae51decf6d3..7b845ff4af99 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -44,6 +44,7 @@
 #include "free-space-cache.h"
 #include "inode-map.h"
 #include "check-integrity.h"
+#include "rcu-string.h"
 
 static struct extent_io_ops btree_extent_io_ops;
 static void end_workqueue_fn(struct btrfs_work *work);
@@ -2118,7 +2119,7 @@ int open_ctree(struct super_block *sb,
 
         features = btrfs_super_incompat_flags(disk_super);
         features |= BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF;
-        if (tree_root->fs_info->compress_type & BTRFS_COMPRESS_LZO)
+        if (tree_root->fs_info->compress_type == BTRFS_COMPRESS_LZO)
                 features |= BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO;
 
         /*
@@ -2575,8 +2576,9 @@ static void btrfs_end_buffer_write_sync(struct buffer_head *bh, int uptodate)
                 struct btrfs_device *device = (struct btrfs_device *)
                         bh->b_private;
 
-                printk_ratelimited(KERN_WARNING "lost page write due to "
-                                   "I/O error on %s\n", device->name);
+                printk_ratelimited_in_rcu(KERN_WARNING "lost page write due to "
+                                          "I/O error on %s\n",
+                                          rcu_str_deref(device->name));
                 /* note, we dont' set_buffer_write_io_error because we have
                  * our own ways of dealing with the IO errors
                  */
@@ -2749,8 +2751,8 @@ static int write_dev_flush(struct btrfs_device *device, int wait)
                 wait_for_completion(&device->flush_wait);
 
                 if (bio_flagged(bio, BIO_EOPNOTSUPP)) {
-                        printk("btrfs: disabling barriers on dev %s\n",
-                               device->name);
+                        printk_in_rcu("btrfs: disabling barriers on dev %s\n",
+                                      rcu_str_deref(device->name));
                         device->nobarriers = 1;
                 }
                 if (!bio_flagged(bio, BIO_UPTODATE)) {
@@ -3400,7 +3402,6 @@ int btrfs_destroy_delayed_refs(struct btrfs_transaction *trans,
 
         delayed_refs = &trans->delayed_refs;
 
-again:
         spin_lock(&delayed_refs->lock);
         if (delayed_refs->num_entries == 0) {
                 spin_unlock(&delayed_refs->lock);
@@ -3408,31 +3409,37 @@ again:
                 return ret;
         }
 
-        node = rb_first(&delayed_refs->root);
-        while (node) {
+        while ((node = rb_first(&delayed_refs->root)) != NULL) {
                 ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node);
-                node = rb_next(node);
-
-                ref->in_tree = 0;
-                rb_erase(&ref->rb_node, &delayed_refs->root);
-                delayed_refs->num_entries--;
 
                 atomic_set(&ref->refs, 1);
                 if (btrfs_delayed_ref_is_head(ref)) {
                         struct btrfs_delayed_ref_head *head;
 
                         head = btrfs_delayed_node_to_head(ref);
-                        spin_unlock(&delayed_refs->lock);
-                        mutex_lock(&head->mutex);
+                        if (!mutex_trylock(&head->mutex)) {
+                                atomic_inc(&ref->refs);
+                                spin_unlock(&delayed_refs->lock);
+
+                                /* Need to wait for the delayed ref to run */
+                                mutex_lock(&head->mutex);
+                                mutex_unlock(&head->mutex);
+                                btrfs_put_delayed_ref(ref);
+
+                                spin_lock(&delayed_refs->lock);
+                                continue;
+                        }
+
                         kfree(head->extent_op);
                         delayed_refs->num_heads--;
                         if (list_empty(&head->cluster))
                                 delayed_refs->num_heads_ready--;
                         list_del_init(&head->cluster);
-                        mutex_unlock(&head->mutex);
-                        btrfs_put_delayed_ref(ref);
-                        goto again;
                 }
+                ref->in_tree = 0;
+                rb_erase(&ref->rb_node, &delayed_refs->root);
+                delayed_refs->num_entries--;
+
                 spin_unlock(&delayed_refs->lock);
                 btrfs_put_delayed_ref(ref);
 
@@ -3520,11 +3527,9 @@ static int btrfs_destroy_marked_extents(struct btrfs_root *root,
                              &(&BTRFS_I(page->mapping->host)->io_tree)->buffer,
                                                offset >> PAGE_CACHE_SHIFT);
                         spin_unlock(&dirty_pages->buffer_lock);
-                        if (eb) {
+                        if (eb)
                                 ret = test_and_clear_bit(EXTENT_BUFFER_DIRTY,
                                                          &eb->bflags);
-                                atomic_set(&eb->refs, 1);
-                        }
                         if (PageWriteback(page))
                                 end_page_writeback(page);
 
@@ -3538,8 +3543,8 @@ static int btrfs_destroy_marked_extents(struct btrfs_root *root,
                                 spin_unlock_irq(&page->mapping->tree_lock);
                         }
 
-                        page->mapping->a_ops->invalidatepage(page, 0);
                         unlock_page(page);
+                        page_cache_release(page);
                 }
         }
 
@@ -3553,8 +3558,10 @@ static int btrfs_destroy_pinned_extent(struct btrfs_root *root,
         u64 start;
         u64 end;
         int ret;
+        bool loop = true;
 
         unpin = pinned_extents;
+again:
         while (1) {
                 ret = find_first_extent_bit(unpin, 0, &start, &end,
                                             EXTENT_DIRTY);
@@ -3572,6 +3579,15 @@ static int btrfs_destroy_pinned_extent(struct btrfs_root *root,
                 cond_resched();
         }
 
+        if (loop) {
+                if (unpin == &root->fs_info->freed_extents[0])
+                        unpin = &root->fs_info->freed_extents[1];
+                else
+                        unpin = &root->fs_info->freed_extents[0];
+                loop = false;
+                goto again;
+        }
+
         return 0;
 }
 
@@ -3585,21 +3601,23 @@ void btrfs_cleanup_one_transaction(struct btrfs_transaction *cur_trans,
         /* FIXME: cleanup wait for commit */
         cur_trans->in_commit = 1;
         cur_trans->blocked = 1;
-        if (waitqueue_active(&root->fs_info->transaction_blocked_wait))
-                wake_up(&root->fs_info->transaction_blocked_wait);
+        wake_up(&root->fs_info->transaction_blocked_wait);
 
         cur_trans->blocked = 0;
-        if (waitqueue_active(&root->fs_info->transaction_wait))
-                wake_up(&root->fs_info->transaction_wait);
+        wake_up(&root->fs_info->transaction_wait);
 
         cur_trans->commit_done = 1;
-        if (waitqueue_active(&cur_trans->commit_wait))
-                wake_up(&cur_trans->commit_wait);
+        wake_up(&cur_trans->commit_wait);
+
+        btrfs_destroy_delayed_inodes(root);
+        btrfs_assert_delayed_root_empty(root);
 
         btrfs_destroy_pending_snapshots(cur_trans);
 
         btrfs_destroy_marked_extents(root, &cur_trans->dirty_pages,
                                      EXTENT_DIRTY);
+        btrfs_destroy_pinned_extent(root,
+                                    root->fs_info->pinned_extents);
 
         /*
         memset(cur_trans, 0, sizeof(*cur_trans));
@@ -3648,6 +3666,9 @@ int btrfs_cleanup_transaction(struct btrfs_root *root)
                 if (waitqueue_active(&t->commit_wait))
                         wake_up(&t->commit_wait);
 
+                btrfs_destroy_delayed_inodes(root);
+                btrfs_assert_delayed_root_empty(root);
+
                 btrfs_destroy_pending_snapshots(t);
 
                 btrfs_destroy_delalloc_inodes(root);
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 2c8f7b204617..aaa12c1eb348 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -20,6 +20,7 @@
 #include "volumes.h"
 #include "check-integrity.h"
 #include "locking.h"
+#include "rcu-string.h"
 
 static struct kmem_cache *extent_state_cache;
 static struct kmem_cache *extent_buffer_cache;
@@ -1917,9 +1918,9 @@ int repair_io_failure(struct btrfs_mapping_tree *map_tree, u64 start,
                 return -EIO;
         }
 
-        printk(KERN_INFO "btrfs read error corrected: ino %lu off %llu (dev %s "
-                        "sector %llu)\n", page->mapping->host->i_ino, start,
-                        dev->name, sector);
+        printk_in_rcu(KERN_INFO "btrfs read error corrected: ino %lu off %llu "
+                      "(dev %s sector %llu)\n", page->mapping->host->i_ino,
+                      start, rcu_str_deref(dev->name), sector);
 
         bio_put(bio);
         return 0;
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index f6ab6f5e635a..d8bb0dbc4941 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -830,7 +830,7 @@ static noinline int cow_file_range(struct inode *inode,
         if (IS_ERR(trans)) {
                 extent_clear_unlock_delalloc(inode,
                              &BTRFS_I(inode)->io_tree,
-                             start, end, NULL,
+                             start, end, locked_page,
                              EXTENT_CLEAR_UNLOCK_PAGE |
                              EXTENT_CLEAR_UNLOCK |
                              EXTENT_CLEAR_DELALLOC |
@@ -963,7 +963,7 @@ out:
 out_unlock:
         extent_clear_unlock_delalloc(inode,
                      &BTRFS_I(inode)->io_tree,
-                     start, end, NULL,
+                     start, end, locked_page,
                      EXTENT_CLEAR_UNLOCK_PAGE |
                      EXTENT_CLEAR_UNLOCK |
                      EXTENT_CLEAR_DELALLOC |
@@ -986,8 +986,10 @@ static noinline void async_cow_start(struct btrfs_work *work)
         compress_file_range(async_cow->inode, async_cow->locked_page,
                             async_cow->start, async_cow->end, async_cow,
                             &num_added);
-        if (num_added == 0)
+        if (num_added == 0) {
+                btrfs_add_delayed_iput(async_cow->inode);
                 async_cow->inode = NULL;
+        }
 }
 
 /*
@@ -1020,6 +1022,8 @@ static noinline void async_cow_free(struct btrfs_work *work)
 {
         struct async_cow *async_cow;
         async_cow = container_of(work, struct async_cow, work);
+        if (async_cow->inode)
+                btrfs_add_delayed_iput(async_cow->inode);
         kfree(async_cow);
 }
 
@@ -1038,7 +1042,7 @@ static int cow_file_range_async(struct inode *inode, struct page *locked_page,
         while (start < end) {
                 async_cow = kmalloc(sizeof(*async_cow), GFP_NOFS);
                 BUG_ON(!async_cow); /* -ENOMEM */
-                async_cow->inode = inode;
+                async_cow->inode = igrab(inode);
                 async_cow->root = root;
                 async_cow->locked_page = locked_page;
                 async_cow->start = start;
@@ -1136,8 +1140,18 @@ static noinline int run_delalloc_nocow(struct inode *inode,
         u64 ino = btrfs_ino(inode);
 
         path = btrfs_alloc_path();
-        if (!path)
+        if (!path) {
+                extent_clear_unlock_delalloc(inode,
+                             &BTRFS_I(inode)->io_tree,
+                             start, end, locked_page,
+                             EXTENT_CLEAR_UNLOCK_PAGE |
+                             EXTENT_CLEAR_UNLOCK |
+                             EXTENT_CLEAR_DELALLOC |
+                             EXTENT_CLEAR_DIRTY |
+                             EXTENT_SET_WRITEBACK |
+                             EXTENT_END_WRITEBACK);
                 return -ENOMEM;
+        }
 
         nolock = btrfs_is_free_space_inode(root, inode);
 
@@ -1147,6 +1161,15 @@ static noinline int run_delalloc_nocow(struct inode *inode,
                 trans = btrfs_join_transaction(root);
 
         if (IS_ERR(trans)) {
+                extent_clear_unlock_delalloc(inode,
+                             &BTRFS_I(inode)->io_tree,
+                             start, end, locked_page,
+                             EXTENT_CLEAR_UNLOCK_PAGE |
+                             EXTENT_CLEAR_UNLOCK |
+                             EXTENT_CLEAR_DELALLOC |
+                             EXTENT_CLEAR_DIRTY |
+                             EXTENT_SET_WRITEBACK |
+                             EXTENT_END_WRITEBACK);
                 btrfs_free_path(path);
                 return PTR_ERR(trans);
         }
@@ -1327,8 +1350,11 @@ out_check:
         }
         btrfs_release_path(path);
 
-        if (cur_offset <= end && cow_start == (u64)-1)
+        if (cur_offset <= end && cow_start == (u64)-1) {
                 cow_start = cur_offset;
+                cur_offset = end;
+        }
+
         if (cow_start != (u64)-1) {
                 ret = cow_file_range(inode, locked_page, cow_start, end,
                                      page_started, nr_written, 1);
@@ -1347,6 +1373,17 @@ error:
         if (!ret)
                 ret = err;
 
+        if (ret && cur_offset < end)
+                extent_clear_unlock_delalloc(inode,
+                             &BTRFS_I(inode)->io_tree,
+                             cur_offset, end, locked_page,
+                             EXTENT_CLEAR_UNLOCK_PAGE |
+                             EXTENT_CLEAR_UNLOCK |
+                             EXTENT_CLEAR_DELALLOC |
+                             EXTENT_CLEAR_DIRTY |
+                             EXTENT_SET_WRITEBACK |
+                             EXTENT_END_WRITEBACK);
+
         btrfs_free_path(path);
         return ret;
 }
@@ -1361,20 +1398,23 @@ static int run_delalloc_range(struct inode *inode, struct page *locked_page,
         int ret;
         struct btrfs_root *root = BTRFS_I(inode)->root;
 
-        if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW)
+        if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW) {
                 ret = run_delalloc_nocow(inode, locked_page, start, end,
                                          page_started, 1, nr_written);
-        else if (BTRFS_I(inode)->flags & BTRFS_INODE_PREALLOC)
+        } else if (BTRFS_I(inode)->flags & BTRFS_INODE_PREALLOC) {
                 ret = run_delalloc_nocow(inode, locked_page, start, end,
                                          page_started, 0, nr_written);
-        else if (!btrfs_test_opt(root, COMPRESS) &&
-                 !(BTRFS_I(inode)->force_compress) &&
-                 !(BTRFS_I(inode)->flags & BTRFS_INODE_COMPRESS))
+        } else if (!btrfs_test_opt(root, COMPRESS) &&
+                   !(BTRFS_I(inode)->force_compress) &&
+                   !(BTRFS_I(inode)->flags & BTRFS_INODE_COMPRESS)) {
                 ret = cow_file_range(inode, locked_page, start, end,
                                       page_started, nr_written, 1);
-        else
+        } else {
+                set_bit(BTRFS_INODE_HAS_ASYNC_EXTENT,
+                        &BTRFS_I(inode)->runtime_flags);
                 ret = cow_file_range_async(inode, locked_page, start, end,
                                            page_started, nr_written);
+        }
         return ret;
 }
 
@@ -7054,10 +7094,13 @@ static void fixup_inode_flags(struct inode *dir, struct inode *inode)
         else
                 b_inode->flags &= ~BTRFS_INODE_NODATACOW;
 
-        if (b_dir->flags & BTRFS_INODE_COMPRESS)
+        if (b_dir->flags & BTRFS_INODE_COMPRESS) {
                 b_inode->flags |= BTRFS_INODE_COMPRESS;
-        else
-                b_inode->flags &= ~BTRFS_INODE_COMPRESS;
+                b_inode->flags &= ~BTRFS_INODE_NOCOMPRESS;
+        } else {
+                b_inode->flags &= ~(BTRFS_INODE_COMPRESS |
+                                    BTRFS_INODE_NOCOMPRESS);
+        }
 }
 
 static int btrfs_rename(struct inode *old_dir, struct dentry *old_dentry,
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 24b776c08d99..0e92e5763005 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -52,6 +52,7 @@
 #include "locking.h"
 #include "inode-map.h"
 #include "backref.h"
+#include "rcu-string.h"
 
 /* Mask out flags that are inappropriate for the given type of inode. */
 static inline __u32 btrfs_mask_flags(umode_t mode, __u32 flags)
@@ -785,39 +786,57 @@ none:
         return -ENOENT;
 }
 
-/*
- * Validaty check of prev em and next em:
- * 1) no prev/next em
- * 2) prev/next em is an hole/inline extent
- */
-static int check_adjacent_extents(struct inode *inode, struct extent_map *em)
+static struct extent_map *defrag_lookup_extent(struct inode *inode, u64 start)
 {
         struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
-        struct extent_map *prev = NULL, *next = NULL;
-        int ret = 0;
+        struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
+        struct extent_map *em;
+        u64 len = PAGE_CACHE_SIZE;
 
+        /*
+         * hopefully we have this extent in the tree already, try without
+         * the full extent lock
+         */
         read_lock(&em_tree->lock);
-        prev = lookup_extent_mapping(em_tree, em->start - 1, (u64)-1);
-        next = lookup_extent_mapping(em_tree, em->start + em->len, (u64)-1);
+        em = lookup_extent_mapping(em_tree, start, len);
         read_unlock(&em_tree->lock);
 
-        if ((!prev || prev->block_start >= EXTENT_MAP_LAST_BYTE) &&
-            (!next || next->block_start >= EXTENT_MAP_LAST_BYTE))
-                ret = 1;
-        free_extent_map(prev);
-        free_extent_map(next);
+        if (!em) {
+                /* get the big lock and read metadata off disk */
+                lock_extent(io_tree, start, start + len - 1);
+                em = btrfs_get_extent(inode, NULL, 0, start, len, 0);
+                unlock_extent(io_tree, start, start + len - 1);
+
+                if (IS_ERR(em))
+                        return NULL;
+        }
+
+        return em;
+}
+
+static bool defrag_check_next_extent(struct inode *inode, struct extent_map *em)
+{
+        struct extent_map *next;
+        bool ret = true;
 
+        /* this is the last extent */
+        if (em->start + em->len >= i_size_read(inode))
+                return false;
+
+        next = defrag_lookup_extent(inode, em->start + em->len);
+        if (!next || next->block_start >= EXTENT_MAP_LAST_BYTE)
+                ret = false;
+
+        free_extent_map(next);
         return ret;
 }
 
-static int should_defrag_range(struct inode *inode, u64 start, u64 len,
-                               int thresh, u64 *last_len, u64 *skip,
-                               u64 *defrag_end)
+static int should_defrag_range(struct inode *inode, u64 start, int thresh,
+                               u64 *last_len, u64 *skip, u64 *defrag_end)
 {
-        struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
-        struct extent_map *em = NULL;
-        struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
+        struct extent_map *em;
         int ret = 1;
+        bool next_mergeable = true;
 
         /*
          * make sure that once we start defragging an extent, we keep on
@@ -828,23 +847,9 @@ static int should_defrag_range(struct inode *inode, u64 start, u64 len,
 
         *skip = 0;
 
-        /*
-         * hopefully we have this extent in the tree already, try without
-         * the full extent lock
-         */
-        read_lock(&em_tree->lock);
-        em = lookup_extent_mapping(em_tree, start, len);
-        read_unlock(&em_tree->lock);
-
-        if (!em) {
-                /* get the big lock and read metadata off disk */
-                lock_extent(io_tree, start, start + len - 1);
-                em = btrfs_get_extent(inode, NULL, 0, start, len, 0);
-                unlock_extent(io_tree, start, start + len - 1);
-
-                if (IS_ERR(em))
-                        return 0;
-        }
+        em = defrag_lookup_extent(inode, start);
+        if (!em)
+                return 0;
 
         /* this will cover holes, and inline extents */
         if (em->block_start >= EXTENT_MAP_LAST_BYTE) {
@@ -852,18 +857,15 @@ static int should_defrag_range(struct inode *inode, u64 start, u64 len,
                 goto out;
         }
 
-        /* If we have nothing to merge with us, just skip. */
-        if (check_adjacent_extents(inode, em)) {
-                ret = 0;
-                goto out;
-        }
+        next_mergeable = defrag_check_next_extent(inode, em);
 
         /*
-         * we hit a real extent, if it is big don't bother defragging it again
+         * we hit a real extent, if it is big or the next extent is not a
+         * real extent, don't bother defragging it
          */
-        if ((*last_len == 0 || *last_len >= thresh) && em->len >= thresh)
+        if ((*last_len == 0 || *last_len >= thresh) &&
+            (em->len >= thresh || !next_mergeable))
                 ret = 0;
-
 out:
         /*
          * last_len ends up being a counter of how many bytes we've defragged.
@@ -1142,8 +1144,8 @@ int btrfs_defrag_file(struct inode *inode, struct file *file,
                         break;
 
                 if (!should_defrag_range(inode, (u64)i << PAGE_CACHE_SHIFT,
-                                         PAGE_CACHE_SIZE, extent_thresh,
-                                         &last_len, &skip, &defrag_end)) {
+                                         extent_thresh, &last_len, &skip,
+                                         &defrag_end)) {
                         unsigned long next;
                         /*
                          * the should_defrag function tells us how much to skip
@@ -1304,6 +1306,14 @@ static noinline int btrfs_ioctl_resize(struct btrfs_root *root,
                 ret = -EINVAL;
                 goto out_free;
         }
+        if (device->fs_devices && device->fs_devices->seeding) {
+                printk(KERN_INFO "btrfs: resizer unable to apply on "
+                       "seeding device %llu\n",
+                       (unsigned long long)devid);
+                ret = -EINVAL;
+                goto out_free;
+        }
+
         if (!strcmp(sizestr, "max"))
                 new_size = device->bdev->bd_inode->i_size;
         else {
@@ -1345,8 +1355,9 @@ static noinline int btrfs_ioctl_resize(struct btrfs_root *root,
         do_div(new_size, root->sectorsize);
         new_size *= root->sectorsize;
 
-        printk(KERN_INFO "btrfs: new size for %s is %llu\n",
-                device->name, (unsigned long long)new_size);
+        printk_in_rcu(KERN_INFO "btrfs: new size for %s is %llu\n",
+                      rcu_str_deref(device->name),
+                      (unsigned long long)new_size);
 
         if (new_size > old_size) {
                 trans = btrfs_start_transaction(root, 0);
@@ -2264,7 +2275,12 @@ static long btrfs_ioctl_dev_info(struct btrfs_root *root, void __user *arg)
         di_args->total_bytes = dev->total_bytes;
         memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid));
         if (dev->name) {
-                strncpy(di_args->path, dev->name, sizeof(di_args->path));
+                struct rcu_string *name;
+
+                rcu_read_lock();
+                name = rcu_dereference(dev->name);
+                strncpy(di_args->path, name->str, sizeof(di_args->path));
+                rcu_read_unlock();
                 di_args->path[sizeof(di_args->path) - 1] = 0;
         } else {
                 di_args->path[0] = '\0';
diff --git a/fs/btrfs/ordered-data.c b/fs/btrfs/ordered-data.c
index 9e138cdc36c5..643335a4fe3c 100644
--- a/fs/btrfs/ordered-data.c
+++ b/fs/btrfs/ordered-data.c
@@ -627,7 +627,27 @@ void btrfs_wait_ordered_range(struct inode *inode, u64 start, u64 len)
         /* start IO across the range first to instantiate any delalloc
          * extents
          */
-        filemap_write_and_wait_range(inode->i_mapping, start, orig_end);
+        filemap_fdatawrite_range(inode->i_mapping, start, orig_end);
+
+        /*
+         * So with compression we will find and lock a dirty page and clear the
+         * first one as dirty, setup an async extent, and immediately return
+         * with the entire range locked but with nobody actually marked with
+         * writeback.  So we can't just filemap_write_and_wait_range() and
+         * expect it to work since it will just kick off a thread to do the
+         * actual work.  So we need to call filemap_fdatawrite_range _again_
+         * since it will wait on the page lock, which won't be unlocked until
+         * after the pages have been marked as writeback and so we're good to go
+         * from there.  We have to do this otherwise we'll miss the ordered
+         * extents and that results in badness.  Please Josef, do not think you
+         * know better and pull this out at some point in the future, it is
+         * right and you are wrong.
+         */
+        if (test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT,
+                     &BTRFS_I(inode)->runtime_flags))
+                filemap_fdatawrite_range(inode->i_mapping, start, orig_end);
+
+        filemap_fdatawait_range(inode->i_mapping, start, orig_end);
 
         end = orig_end;
         found = 0;
diff --git a/fs/btrfs/rcu-string.h b/fs/btrfs/rcu-string.h
new file mode 100644
index 000000000000..9e111e4576d4
--- /dev/null
+++ b/fs/btrfs/rcu-string.h
@@ -0,0 +1,56 @@
+/*
+ * Copyright (C) 2012 Red Hat.  All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License v2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this program; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 021110-1307, USA.
+ */
+
+struct rcu_string {
+        struct rcu_head rcu;
+        char str[0];
+};
+
+static inline struct rcu_string *rcu_string_strdup(const char *src, gfp_t mask)
+{
+        size_t len = strlen(src) + 1;
+        struct rcu_string *ret = kzalloc(sizeof(struct rcu_string) +
+                                         (len * sizeof(char)), mask);
+        if (!ret)
+                return ret;
+        strncpy(ret->str, src, len);
+        return ret;
+}
+
+static inline void rcu_string_free(struct rcu_string *str)
+{
+        if (str)
+                kfree_rcu(str, rcu);
+}
+
+#define printk_in_rcu(fmt, ...) do {    \
+        rcu_read_lock();                \
+        printk(fmt, __VA_ARGS__);       \
+        rcu_read_unlock();              \
+} while (0)
+
+#define printk_ratelimited_in_rcu(fmt, ...) do {        \
+        rcu_read_lock();                                \
+        printk_ratelimited(fmt, __VA_ARGS__);           \
+        rcu_read_unlock();                              \
+} while (0)
+
+#define rcu_str_deref(rcu_str) ({                               \
+        struct rcu_string *__str = rcu_dereference(rcu_str);    \
+        __str->str;                                             \
+})
diff --git a/fs/btrfs/scrub.c b/fs/btrfs/scrub.c
index a38cfa4f251e..b223620cd5a6 100644
--- a/fs/btrfs/scrub.c
+++ b/fs/btrfs/scrub.c
@@ -26,6 +26,7 @@
 #include "backref.h"
 #include "extent_io.h"
 #include "check-integrity.h"
+#include "rcu-string.h"
 
 /*
  * This is only the first step towards a full-features scrub. It reads all
@@ -320,10 +321,10 @@ static int scrub_print_warning_inode(u64 inum, u64 offset, u64 root, void *ctx)
          * hold all of the paths here
          */
         for (i = 0; i < ipath->fspath->elem_cnt; ++i)
-                printk(KERN_WARNING "btrfs: %s at logical %llu on dev "
+                printk_in_rcu(KERN_WARNING "btrfs: %s at logical %llu on dev "
                         "%s, sector %llu, root %llu, inode %llu, offset %llu, "
                         "length %llu, links %u (path: %s)\n", swarn->errstr,
-                        swarn->logical, swarn->dev->name,
+                        swarn->logical, rcu_str_deref(swarn->dev->name),
                         (unsigned long long)swarn->sector, root, inum, offset,
                         min(isize - offset, (u64)PAGE_SIZE), nlink,
                         (char *)(unsigned long)ipath->fspath->val[i]);
@@ -332,10 +333,10 @@ static int scrub_print_warning_inode(u64 inum, u64 offset, u64 root, void *ctx)
         return 0;
 
 err:
-        printk(KERN_WARNING "btrfs: %s at logical %llu on dev "
+        printk_in_rcu(KERN_WARNING "btrfs: %s at logical %llu on dev "
                 "%s, sector %llu, root %llu, inode %llu, offset %llu: path "
                 "resolving failed with ret=%d\n", swarn->errstr,
-                swarn->logical, swarn->dev->name,
+                swarn->logical, rcu_str_deref(swarn->dev->name),
                 (unsigned long long)swarn->sector, root, inum, offset, ret);
 
         free_ipath(ipath);
@@ -390,10 +391,11 @@ static void scrub_print_warning(const char *errstr, struct scrub_block *sblock)
                 do {
                         ret = tree_backref_for_extent(&ptr, eb, ei, item_size,
                                                         &ref_root, &ref_level);
-                        printk(KERN_WARNING
+                        printk_in_rcu(KERN_WARNING
                                 "btrfs: %s at logical %llu on dev %s, "
                                 "sector %llu: metadata %s (level %d) in tree "
-                                "%llu\n", errstr, swarn.logical, dev->name,
+                                "%llu\n", errstr, swarn.logical,
+                                rcu_str_deref(dev->name),
                                 (unsigned long long)swarn.sector,
                                 ref_level ? "node" : "leaf",
                                 ret < 0 ? -1 : ref_level,
@@ -580,9 +582,11 @@ out:
                 spin_lock(&sdev->stat_lock);
                 ++sdev->stat.uncorrectable_errors;
                 spin_unlock(&sdev->stat_lock);
-                printk_ratelimited(KERN_ERR
+
+                printk_ratelimited_in_rcu(KERN_ERR
                         "btrfs: unable to fixup (nodatasum) error at logical %llu on dev %s\n",
-                        (unsigned long long)fixup->logical, sdev->dev->name);
+                        (unsigned long long)fixup->logical,
+                        rcu_str_deref(sdev->dev->name));
         }
 
         btrfs_free_path(path);
@@ -936,18 +940,20 @@ corrected_error:
                         spin_lock(&sdev->stat_lock);
                         sdev->stat.corrected_errors++;
                         spin_unlock(&sdev->stat_lock);
-                        printk_ratelimited(KERN_ERR
+                        printk_ratelimited_in_rcu(KERN_ERR
                                 "btrfs: fixed up error at logical %llu on dev %s\n",
-                                (unsigned long long)logical, sdev->dev->name);
+                                (unsigned long long)logical,
+                                rcu_str_deref(sdev->dev->name));
                 }
         } else {
 did_not_correct_error:
                 spin_lock(&sdev->stat_lock);
                 sdev->stat.uncorrectable_errors++;
                 spin_unlock(&sdev->stat_lock);
-                printk_ratelimited(KERN_ERR
+                printk_ratelimited_in_rcu(KERN_ERR
                         "btrfs: unable to fixup (regular) error at logical %llu on dev %s\n",
-                        (unsigned long long)logical, sdev->dev->name);
+                        (unsigned long long)logical,
+                        rcu_str_deref(sdev->dev->name));
         }
 
 out:
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 96eb9fef7bd2..0eb9a4da069e 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -54,6 +54,7 @@
 #include "version.h"
 #include "export.h"
 #include "compression.h"
+#include "rcu-string.h"
 
 #define CREATE_TRACE_POINTS
 #include <trace/events/btrfs.h>
@@ -1482,12 +1483,44 @@ static void btrfs_fs_dirty_inode(struct inode *inode, int flags)
                                    "error %d\n", btrfs_ino(inode), ret);
 }
 
+static int btrfs_show_devname(struct seq_file *m, struct dentry *root)
+{
+        struct btrfs_fs_info *fs_info = btrfs_sb(root->d_sb);
+        struct btrfs_fs_devices *cur_devices;
+        struct btrfs_device *dev, *first_dev = NULL;
+        struct list_head *head;
+        struct rcu_string *name;
+
+        mutex_lock(&fs_info->fs_devices->device_list_mutex);
+        cur_devices = fs_info->fs_devices;
+        while (cur_devices) {
+                head = &cur_devices->devices;
+                list_for_each_entry(dev, head, dev_list) {
+                        if (!first_dev || dev->devid < first_dev->devid)
+                                first_dev = dev;
+                }
+                cur_devices = cur_devices->seed;
+        }
+
+        if (first_dev) {
+                rcu_read_lock();
+                name = rcu_dereference(first_dev->name);
+                seq_escape(m, name->str, " \t\n\\");
+                rcu_read_unlock();
+        } else {
+                WARN_ON(1);
+        }
+        mutex_unlock(&fs_info->fs_devices->device_list_mutex);
+        return 0;
+}
+
 static const struct super_operations btrfs_super_ops = {
         .drop_inode     = btrfs_drop_inode,
         .evict_inode    = btrfs_evict_inode,
         .put_super      = btrfs_put_super,
         .sync_fs        = btrfs_sync_fs,
         .show_options   = btrfs_show_options,
+        .show_devname   = btrfs_show_devname,
         .write_inode    = btrfs_write_inode,
         .dirty_inode    = btrfs_fs_dirty_inode,
         .alloc_inode    = btrfs_alloc_inode,
diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index 1791c6e3d834..b72b068183ec 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -100,6 +100,10 @@ loop:
                 kmem_cache_free(btrfs_transaction_cachep, cur_trans);
                 cur_trans = fs_info->running_transaction;
                 goto loop;
+        } else if (root->fs_info->fs_state & BTRFS_SUPER_FLAG_ERROR) {
+                spin_unlock(&root->fs_info->trans_lock);
+                kmem_cache_free(btrfs_transaction_cachep, cur_trans);
+                return -EROFS;
         }
 
         atomic_set(&cur_trans->num_writers, 1);
@@ -1213,14 +1217,20 @@ int btrfs_commit_transaction_async(struct btrfs_trans_handle *trans,
 
 
 static void cleanup_transaction(struct btrfs_trans_handle *trans,
-                                struct btrfs_root *root)
+                                struct btrfs_root *root, int err)
 {
         struct btrfs_transaction *cur_trans = trans->transaction;
 
         WARN_ON(trans->use_count > 1);
 
+        btrfs_abort_transaction(trans, root, err);
+
         spin_lock(&root->fs_info->trans_lock);
         list_del_init(&cur_trans->list);
+        if (cur_trans == root->fs_info->running_transaction) {
+                root->fs_info->running_transaction = NULL;
+                root->fs_info->trans_no_join = 0;
+        }
         spin_unlock(&root->fs_info->trans_lock);
 
         btrfs_cleanup_one_transaction(trans->transaction, root);
@@ -1526,7 +1536,7 @@ cleanup_transaction:
 //      WARN_ON(1);
         if (current->journal_info == trans)
                 current->journal_info = NULL;
-        cleanup_transaction(trans, root);
+        cleanup_transaction(trans, root, ret);
 
         return ret;
 }
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 7782020996fe..8a3d2594b807 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -35,6 +35,7 @@
 #include "volumes.h"
 #include "async-thread.h"
 #include "check-integrity.h"
+#include "rcu-string.h"
 
 static int init_first_rw_device(struct btrfs_trans_handle *trans,
                                 struct btrfs_root *root,
@@ -64,7 +65,7 @@ static void free_fs_devices(struct btrfs_fs_devices *fs_devices)
                 device = list_entry(fs_devices->devices.next,
                                     struct btrfs_device, dev_list);
                 list_del(&device->dev_list);
-                kfree(device->name);
+                rcu_string_free(device->name);
                 kfree(device);
         }
         kfree(fs_devices);
@@ -334,8 +335,8 @@ static noinline int device_list_add(const char *path,
 {
         struct btrfs_device *device;
         struct btrfs_fs_devices *fs_devices;
+        struct rcu_string *name;
         u64 found_transid = btrfs_super_generation(disk_super);
-        char *name;
 
         fs_devices = find_fsid(disk_super->fsid);
         if (!fs_devices) {
@@ -369,11 +370,13 @@ static noinline int device_list_add(const char *path,
                 memcpy(device->uuid, disk_super->dev_item.uuid,
                        BTRFS_UUID_SIZE);
                 spin_lock_init(&device->io_lock);
-                device->name = kstrdup(path, GFP_NOFS);
-                if (!device->name) {
+
+                name = rcu_string_strdup(path, GFP_NOFS);
+                if (!name) {
                         kfree(device);
                         return -ENOMEM;
                 }
+                rcu_assign_pointer(device->name, name);
                 INIT_LIST_HEAD(&device->dev_alloc_list);
 
                 /* init readahead state */
@@ -390,12 +393,12 @@ static noinline int device_list_add(const char *path,
 
                 device->fs_devices = fs_devices;
                 fs_devices->num_devices++;
-        } else if (!device->name || strcmp(device->name, path)) {
-                name = kstrdup(path, GFP_NOFS);
+        } else if (!device->name || strcmp(device->name->str, path)) {
+                name = rcu_string_strdup(path, GFP_NOFS);
                 if (!name)
                         return -ENOMEM;
-                kfree(device->name);
-                device->name = name;
+                rcu_string_free(device->name);
+                rcu_assign_pointer(device->name, name);
                 if (device->missing) {
                         fs_devices->missing_devices--;
                         device->missing = 0;
@@ -430,15 +433,22 @@ static struct btrfs_fs_devices *clone_fs_devices(struct btrfs_fs_devices *orig)
 
         /* We have held the volume lock, it is safe to get the devices. */
         list_for_each_entry(orig_dev, &orig->devices, dev_list) {
+                struct rcu_string *name;
+
                 device = kzalloc(sizeof(*device), GFP_NOFS);
                 if (!device)
                         goto error;
 
-                device->name = kstrdup(orig_dev->name, GFP_NOFS);
-                if (!device->name) {
+                /*
+                 * This is ok to do without rcu read locked because we hold the
+                 * uuid mutex so nothing we touch in here is going to disappear.
+                 */
+                name = rcu_string_strdup(orig_dev->name->str, GFP_NOFS);
+                if (!name) {
                         kfree(device);
                         goto error;
                 }
+                rcu_assign_pointer(device->name, name);
 
                 device->devid = orig_dev->devid;
                 device->work.func = pending_bios_fn;
@@ -491,7 +501,7 @@ again:
                 }
                 list_del_init(&device->dev_list);
                 fs_devices->num_devices--;
-                kfree(device->name);
+                rcu_string_free(device->name);
                 kfree(device);
         }
 
@@ -516,7 +526,7 @@ static void __free_device(struct work_struct *work)
         if (device->bdev)
                 blkdev_put(device->bdev, device->mode);
 
-        kfree(device->name);
+        rcu_string_free(device->name);
         kfree(device);
 }
 
@@ -540,6 +550,7 @@ static int __btrfs_close_devices(struct btrfs_fs_devices *fs_devices)
         mutex_lock(&fs_devices->device_list_mutex);
         list_for_each_entry(device, &fs_devices->devices, dev_list) {
                 struct btrfs_device *new_device;
+                struct rcu_string *name;
 
                 if (device->bdev)
                         fs_devices->open_devices--;
@@ -555,8 +566,11 @@ static int __btrfs_close_devices(struct btrfs_fs_devices *fs_devices)
                 new_device = kmalloc(sizeof(*new_device), GFP_NOFS);
                 BUG_ON(!new_device); /* -ENOMEM */
                 memcpy(new_device, device, sizeof(*new_device));
-                new_device->name = kstrdup(device->name, GFP_NOFS);
-                BUG_ON(device->name && !new_device->name); /* -ENOMEM */
+
+                /* Safe because we are under uuid_mutex */
+                name = rcu_string_strdup(device->name->str, GFP_NOFS);
+                BUG_ON(device->name && !name); /* -ENOMEM */
+                rcu_assign_pointer(new_device->name, name);
                 new_device->bdev = NULL;
                 new_device->writeable = 0;
                 new_device->in_fs_metadata = 0;
@@ -621,9 +635,9 @@ static int __btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
                 if (!device->name)
                         continue;
 
-                bdev = blkdev_get_by_path(device->name, flags, holder);
+                bdev = blkdev_get_by_path(device->name->str, flags, holder);
                 if (IS_ERR(bdev)) {
-                        printk(KERN_INFO "open %s failed\n", device->name);
+                        printk(KERN_INFO "open %s failed\n", device->name->str);
                         goto error;
                 }
                 filemap_write_and_wait(bdev->bd_inode->i_mapping);
@@ -1632,6 +1646,7 @@ int btrfs_init_new_device(struct btrfs_root *root, char *device_path)
         struct block_device *bdev;
         struct list_head *devices;
         struct super_block *sb = root->fs_info->sb;
+        struct rcu_string *name;
         u64 total_bytes;
         int seeding_dev = 0;
         int ret = 0;
@@ -1671,23 +1686,24 @@ int btrfs_init_new_device(struct btrfs_root *root, char *device_path)
                 goto error;
         }
 
-        device->name = kstrdup(device_path, GFP_NOFS);
-        if (!device->name) {
+        name = rcu_string_strdup(device_path, GFP_NOFS);
+        if (!name) {
                 kfree(device);
                 ret = -ENOMEM;
                 goto error;
         }
+        rcu_assign_pointer(device->name, name);
 
         ret = find_next_devid(root, &device->devid);
         if (ret) {
-                kfree(device->name);
+                rcu_string_free(device->name);
                 kfree(device);
                 goto error;
         }
 
         trans = btrfs_start_transaction(root, 0);
         if (IS_ERR(trans)) {
-                kfree(device->name);
+                rcu_string_free(device->name);
                 kfree(device);
                 ret = PTR_ERR(trans);
                 goto error;
@@ -1796,7 +1812,7 @@ error_trans:
         unlock_chunks(root);
         btrfs_abort_transaction(trans, root, ret);
         btrfs_end_transaction(trans, root);
-        kfree(device->name);
+        rcu_string_free(device->name);
         kfree(device);
 error:
         blkdev_put(bdev, FMODE_EXCL);
@@ -4204,10 +4220,17 @@ int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio,
                 bio->bi_sector = bbio->stripes[dev_nr].physical >> 9;
                 dev = bbio->stripes[dev_nr].dev;
                 if (dev && dev->bdev && (rw != WRITE || dev->writeable)) {
+#ifdef DEBUG
+                        struct rcu_string *name;
+
+                        rcu_read_lock();
+                        name = rcu_dereference(dev->name);
                         pr_debug("btrfs_map_bio: rw %d, secor=%llu, dev=%lu "
                                  "(%s id %llu), size=%u\n", rw,
                                  (u64)bio->bi_sector, (u_long)dev->bdev->bd_dev,
-                                 dev->name, dev->devid, bio->bi_size);
+                                 name->str, dev->devid, bio->bi_size);
+                        rcu_read_unlock();
+#endif
                         bio->bi_bdev = dev->bdev;
                         if (async_submit)
                                 schedule_bio(root, dev, rw, bio);
@@ -4694,8 +4717,9 @@ int btrfs_init_dev_stats(struct btrfs_fs_info *fs_info)
                 key.offset = device->devid;
                 ret = btrfs_search_slot(NULL, dev_root, &key, path, 0, 0);
                 if (ret) {
-                        printk(KERN_WARNING "btrfs: no dev_stats entry found for device %s (devid %llu) (OK on first mount after mkfs)\n",
-                               device->name, (unsigned long long)device->devid);
+                        printk_in_rcu(KERN_WARNING "btrfs: no dev_stats entry found for device %s (devid %llu) (OK on first mount after mkfs)\n",
+                                      rcu_str_deref(device->name),
+                                      (unsigned long long)device->devid);
                         __btrfs_reset_dev_stats(device);
                         device->dev_stats_valid = 1;
                         btrfs_release_path(path);
@@ -4747,8 +4771,8 @@ static int update_dev_stat_item(struct btrfs_trans_handle *trans,
         BUG_ON(!path);
         ret = btrfs_search_slot(trans, dev_root, &key, path, -1, 1);
         if (ret < 0) {
-                printk(KERN_WARNING "btrfs: error %d while searching for dev_stats item for device %s!\n",
-                       ret, device->name);
+                printk_in_rcu(KERN_WARNING "btrfs: error %d while searching for dev_stats item for device %s!\n",
+                              ret, rcu_str_deref(device->name));
                 goto out;
         }
 
@@ -4757,8 +4781,8 @@ static int update_dev_stat_item(struct btrfs_trans_handle *trans,
                 /* need to delete old one and insert a new one */
                 ret = btrfs_del_item(trans, dev_root, path);
                 if (ret != 0) {
-                        printk(KERN_WARNING "btrfs: delete too small dev_stats item for device %s failed %d!\n",
-                               device->name, ret);
+                        printk_in_rcu(KERN_WARNING "btrfs: delete too small dev_stats item for device %s failed %d!\n",
+                                      rcu_str_deref(device->name), ret);
                         goto out;
                 }
                 ret = 1;
@@ -4770,8 +4794,8 @@ static int update_dev_stat_item(struct btrfs_trans_handle *trans,
                 ret = btrfs_insert_empty_item(trans, dev_root, path,
                                               &key, sizeof(*ptr));
                 if (ret < 0) {
-                        printk(KERN_WARNING "btrfs: insert dev_stats item for device %s failed %d!\n",
-                               device->name, ret);
+                        printk_in_rcu(KERN_WARNING "btrfs: insert dev_stats item for device %s failed %d!\n",
+                                      rcu_str_deref(device->name), ret);
                         goto out;
                 }
         }
@@ -4823,9 +4847,9 @@ void btrfs_dev_stat_print_on_error(struct btrfs_device *dev)
 {
         if (!dev->dev_stats_valid)
                 return;
-        printk_ratelimited(KERN_ERR
+        printk_ratelimited_in_rcu(KERN_ERR
                            "btrfs: bdev %s errs: wr %u, rd %u, flush %u, corrupt %u, gen %u\n",
-                           dev->name,
+                           rcu_str_deref(dev->name),
                            btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_WRITE_ERRS),
                            btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_READ_ERRS),
                            btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_FLUSH_ERRS),
@@ -4837,8 +4861,8 @@ void btrfs_dev_stat_print_on_error(struct btrfs_device *dev)
 
 static void btrfs_dev_stat_print_on_load(struct btrfs_device *dev)
 {
-        printk(KERN_INFO "btrfs: bdev %s errs: wr %u, rd %u, flush %u, corrupt %u, gen %u\n",
-               dev->name,
+        printk_in_rcu(KERN_INFO "btrfs: bdev %s errs: wr %u, rd %u, flush %u, corrupt %u, gen %u\n",
+               rcu_str_deref(dev->name),
                btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_WRITE_ERRS),
                btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_READ_ERRS),
                btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_FLUSH_ERRS),
diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h
index 3406a88ca83e..74366f27a76b 100644
--- a/fs/btrfs/volumes.h
+++ b/fs/btrfs/volumes.h
@@ -58,7 +58,7 @@ struct btrfs_device {
         /* the mode sent to blkdev_get */
         fmode_t mode;
 
-        char *name;
+        struct rcu_string *name;
 
         /* the internal btrfs device id */
         u64 devid;