Merge branch 'master' into for-next

Conflicts:
	drivers/devfreq/exynos4_bus.c

Sync with Linus' tree to be able to apply patches that are
against newer code (mvneta).

1 files changed, 387 insertions, 230 deletions

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 95542a1b3dfc..cc93b23ca352 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -71,6 +71,7 @@ static const struct file_operations btrfs_dir_file_operations;
 static struct extent_io_ops btrfs_extent_io_ops;
 
 static struct kmem_cache *btrfs_inode_cachep;
+static struct kmem_cache *btrfs_delalloc_work_cachep;
 struct kmem_cache *btrfs_trans_handle_cachep;
 struct kmem_cache *btrfs_transaction_cachep;
 struct kmem_cache *btrfs_path_cachep;
@@ -87,13 +88,17 @@ static unsigned char btrfs_type_by_mode[S_IFMT >> S_SHIFT] = {
         [S_IFLNK >> S_SHIFT]    = BTRFS_FT_SYMLINK,
 };
 
-static int btrfs_setsize(struct inode *inode, loff_t newsize);
+static int btrfs_setsize(struct inode *inode, struct iattr *attr);
 static int btrfs_truncate(struct inode *inode);
 static int btrfs_finish_ordered_io(struct btrfs_ordered_extent *ordered_extent);
 static noinline int cow_file_range(struct inode *inode,
                                    struct page *locked_page,
                                    u64 start, u64 end, int *page_started,
                                    unsigned long *nr_written, int unlock);
+static struct extent_map *create_pinned_em(struct inode *inode, u64 start,
+                                           u64 len, u64 orig_start,
+                                           u64 block_start, u64 block_len,
+                                           u64 orig_block_len, int type);
 
 static int btrfs_init_inode_security(struct btrfs_trans_handle *trans,
                                      struct inode *inode,  struct inode *dir,
@@ -698,14 +703,19 @@ retry:
 
                 em->block_start = ins.objectid;
                 em->block_len = ins.offset;
+                em->orig_block_len = ins.offset;
                 em->bdev = root->fs_info->fs_devices->latest_bdev;
                 em->compress_type = async_extent->compress_type;
                 set_bit(EXTENT_FLAG_PINNED, &em->flags);
                 set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
+                em->generation = -1;
 
                 while (1) {
                         write_lock(&em_tree->lock);
                         ret = add_extent_mapping(em_tree, em);
+                        if (!ret)
+                                list_move(&em->list,
+                                          &em_tree->modified_extents);
                         write_unlock(&em_tree->lock);
                         if (ret != -EEXIST) {
                                 free_extent_map(em);
@@ -803,14 +813,14 @@ static u64 get_extent_allocation_hint(struct inode *inode, u64 start,
  * required to start IO on it.  It may be clean and already done with
  * IO when we return.
  */
-static noinline int cow_file_range(struct inode *inode,
-                                   struct page *locked_page,
-                                   u64 start, u64 end, int *page_started,
-                                   unsigned long *nr_written,
-                                   int unlock)
+static noinline int __cow_file_range(struct btrfs_trans_handle *trans,
+                                     struct inode *inode,
+                                     struct btrfs_root *root,
+                                     struct page *locked_page,
+                                     u64 start, u64 end, int *page_started,
+                                     unsigned long *nr_written,
+                                     int unlock)
 {
-        struct btrfs_root *root = BTRFS_I(inode)->root;
-        struct btrfs_trans_handle *trans;
         u64 alloc_hint = 0;
         u64 num_bytes;
         unsigned long ram_size;
@@ -823,25 +833,10 @@ static noinline int cow_file_range(struct inode *inode,
         int ret = 0;
 
         BUG_ON(btrfs_is_free_space_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);
-                return PTR_ERR(trans);
-        }
-        trans->block_rsv = &root->fs_info->delalloc_block_rsv;
 
         num_bytes = (end - start + blocksize) & ~(blocksize - 1);
         num_bytes = max(blocksize,  num_bytes);
         disk_num_bytes = num_bytes;
-        ret = 0;
 
         /* if this is a small write inside eof, kick off defrag */
         if (num_bytes < 64 * 1024 &&
@@ -900,12 +895,17 @@ static noinline int cow_file_range(struct inode *inode,
 
                 em->block_start = ins.objectid;
                 em->block_len = ins.offset;
+                em->orig_block_len = ins.offset;
                 em->bdev = root->fs_info->fs_devices->latest_bdev;
                 set_bit(EXTENT_FLAG_PINNED, &em->flags);
+                em->generation = -1;
 
                 while (1) {
                         write_lock(&em_tree->lock);
                         ret = add_extent_mapping(em_tree, em);
+                        if (!ret)
+                                list_move(&em->list,
+                                          &em_tree->modified_extents);
                         write_unlock(&em_tree->lock);
                         if (ret != -EEXIST) {
                                 free_extent_map(em);
@@ -952,11 +952,9 @@ static noinline int cow_file_range(struct inode *inode,
                 alloc_hint = ins.objectid + ins.offset;
                 start += cur_alloc_size;
         }
-        ret = 0;
 out:
-        btrfs_end_transaction(trans, root);
-
         return ret;
+
 out_unlock:
         extent_clear_unlock_delalloc(inode,
                      &BTRFS_I(inode)->io_tree,
@@ -971,6 +969,39 @@ out_unlock:
         goto out;
 }
 
+static noinline int cow_file_range(struct inode *inode,
+                                   struct page *locked_page,
+                                   u64 start, u64 end, int *page_started,
+                                   unsigned long *nr_written,
+                                   int unlock)
+{
+        struct btrfs_trans_handle *trans;
+        struct btrfs_root *root = BTRFS_I(inode)->root;
+        int ret;
+
+        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);
+                return PTR_ERR(trans);
+        }
+        trans->block_rsv = &root->fs_info->delalloc_block_rsv;
+
+        ret = __cow_file_range(trans, inode, root, locked_page, start, end,
+                               page_started, nr_written, unlock);
+
+        btrfs_end_transaction(trans, root);
+
+        return ret;
+}
+
 /*
  * work queue call back to started compression on a file and pages
  */
@@ -1126,6 +1157,7 @@ static noinline int run_delalloc_nocow(struct inode *inode,
         u64 extent_offset;
         u64 disk_bytenr;
         u64 num_bytes;
+        u64 disk_num_bytes;
         int extent_type;
         int ret, err;
         int type;
@@ -1228,6 +1260,8 @@ next_slot:
                         extent_offset = btrfs_file_extent_offset(leaf, fi);
                         extent_end = found_key.offset +
                                 btrfs_file_extent_num_bytes(leaf, fi);
+                        disk_num_bytes =
+                                btrfs_file_extent_disk_num_bytes(leaf, fi);
                         if (extent_end <= start) {
                                 path->slots[0]++;
                                 goto next_slot;
@@ -1281,9 +1315,9 @@ out_check:
 
                 btrfs_release_path(path);
                 if (cow_start != (u64)-1) {
-                        ret = cow_file_range(inode, locked_page, cow_start,
-                                        found_key.offset - 1, page_started,
-                                        nr_written, 1);
+                        ret = __cow_file_range(trans, inode, root, locked_page,
+                                               cow_start, found_key.offset - 1,
+                                               page_started, nr_written, 1);
                         if (ret) {
                                 btrfs_abort_transaction(trans, root, ret);
                                 goto error;
@@ -1298,16 +1332,21 @@ out_check:
                         em = alloc_extent_map();
                         BUG_ON(!em); /* -ENOMEM */
                         em->start = cur_offset;
-                        em->orig_start = em->start;
+                        em->orig_start = found_key.offset - extent_offset;
                         em->len = num_bytes;
                         em->block_len = num_bytes;
                         em->block_start = disk_bytenr;
+                        em->orig_block_len = disk_num_bytes;
                         em->bdev = root->fs_info->fs_devices->latest_bdev;
                         set_bit(EXTENT_FLAG_PINNED, &em->flags);
-                        set_bit(EXTENT_FLAG_PREALLOC, &em->flags);
+                        set_bit(EXTENT_FLAG_FILLING, &em->flags);
+                        em->generation = -1;
                         while (1) {
                                 write_lock(&em_tree->lock);
                                 ret = add_extent_mapping(em_tree, em);
+                                if (!ret)
+                                        list_move(&em->list,
+                                                  &em_tree->modified_extents);
                                 write_unlock(&em_tree->lock);
                                 if (ret != -EEXIST) {
                                         free_extent_map(em);
@@ -1352,8 +1391,9 @@ out_check:
         }
 
         if (cow_start != (u64)-1) {
-                ret = cow_file_range(inode, locked_page, cow_start, end,
-                                     page_started, nr_written, 1);
+                ret = __cow_file_range(trans, inode, root, locked_page,
+                                       cow_start, end,
+                                       page_started, nr_written, 1);
                 if (ret) {
                         btrfs_abort_transaction(trans, root, ret);
                         goto error;
@@ -1531,7 +1571,6 @@ int btrfs_merge_bio_hook(struct page *page, unsigned long offset,
                          unsigned long bio_flags)
 {
         struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
-        struct btrfs_mapping_tree *map_tree;
         u64 logical = (u64)bio->bi_sector << 9;
         u64 length = 0;
         u64 map_length;
@@ -1541,11 +1580,10 @@ int btrfs_merge_bio_hook(struct page *page, unsigned long offset,
                 return 0;
 
         length = bio->bi_size;
-        map_tree = &root->fs_info->mapping_tree;
         map_length = length;
-        ret = btrfs_map_block(map_tree, READ, logical,
+        ret = btrfs_map_block(root->fs_info, READ, logical,
                               &map_length, NULL, 0);
-        /* Will always return 0 or 1 with map_multi == NULL */
+        /* Will always return 0 with map_multi == NULL */
         BUG_ON(ret < 0);
         if (map_length < length + size)
                 return 1;
@@ -1586,7 +1624,12 @@ static int __btrfs_submit_bio_done(struct inode *inode, int rw, struct bio *bio,
                           u64 bio_offset)
 {
         struct btrfs_root *root = BTRFS_I(inode)->root;
-        return btrfs_map_bio(root, rw, bio, mirror_num, 1);
+        int ret;
+
+        ret = btrfs_map_bio(root, rw, bio, mirror_num, 1);
+        if (ret)
+                bio_endio(bio, ret);
+        return ret;
 }
 
 /*
@@ -1601,6 +1644,7 @@ static int btrfs_submit_bio_hook(struct inode *inode, int rw, struct bio *bio,
         int ret = 0;
         int skip_sum;
         int metadata = 0;
+        int async = !atomic_read(&BTRFS_I(inode)->sync_writers);
 
         skip_sum = BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM;
 
@@ -1610,31 +1654,43 @@ static int btrfs_submit_bio_hook(struct inode *inode, int rw, struct bio *bio,
         if (!(rw & REQ_WRITE)) {
                 ret = btrfs_bio_wq_end_io(root->fs_info, bio, metadata);
                 if (ret)
-                        return ret;
+                        goto out;
 
                 if (bio_flags & EXTENT_BIO_COMPRESSED) {
-                        return btrfs_submit_compressed_read(inode, bio,
-                                                    mirror_num, bio_flags);
+                        ret = btrfs_submit_compressed_read(inode, bio,
+                                                           mirror_num,
+                                                           bio_flags);
+                        goto out;
                 } else if (!skip_sum) {
                         ret = btrfs_lookup_bio_sums(root, inode, bio, NULL);
                         if (ret)
-                                return ret;
+                                goto out;
                 }
                 goto mapit;
-        } else if (!skip_sum) {
+        } else if (async && !skip_sum) {
                 /* csum items have already been cloned */
                 if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID)
                         goto mapit;
                 /* we're doing a write, do the async checksumming */
-                return btrfs_wq_submit_bio(BTRFS_I(inode)->root->fs_info,
+                ret = btrfs_wq_submit_bio(BTRFS_I(inode)->root->fs_info,
                                    inode, rw, bio, mirror_num,
                                    bio_flags, bio_offset,
                                    __btrfs_submit_bio_start,
                                    __btrfs_submit_bio_done);
+                goto out;
+        } else if (!skip_sum) {
+                ret = btrfs_csum_one_bio(root, inode, bio, 0, 0);
+                if (ret)
+                        goto out;
         }
 
 mapit:
-        return btrfs_map_bio(root, rw, bio, mirror_num, 0);
+        ret = btrfs_map_bio(root, rw, bio, mirror_num, 0);
+
+out:
+        if (ret < 0)
+                bio_endio(bio, ret);
+        return ret;
 }
 
 /*
@@ -1657,8 +1713,7 @@ static noinline int add_pending_csums(struct btrfs_trans_handle *trans,
 int btrfs_set_extent_delalloc(struct inode *inode, u64 start, u64 end,
                               struct extent_state **cached_state)
 {
-        if ((end & (PAGE_CACHE_SIZE - 1)) == 0)
-                WARN_ON(1);
+        WARN_ON((end & (PAGE_CACHE_SIZE - 1)) == 0);
         return set_extent_delalloc(&BTRFS_I(inode)->io_tree, start, end,
                                    cached_state, GFP_NOFS);
 }
@@ -1867,22 +1922,20 @@ static int btrfs_finish_ordered_io(struct btrfs_ordered_extent *ordered_extent)
 
         if (test_bit(BTRFS_ORDERED_NOCOW, &ordered_extent->flags)) {
                 BUG_ON(!list_empty(&ordered_extent->list)); /* Logic error */
-                ret = btrfs_ordered_update_i_size(inode, 0, ordered_extent);
-                if (!ret) {
-                        if (nolock)
-                                trans = btrfs_join_transaction_nolock(root);
-                        else
-                                trans = btrfs_join_transaction(root);
-                        if (IS_ERR(trans)) {
-                                ret = PTR_ERR(trans);
-                                trans = NULL;
-                                goto out;
-                        }
-                        trans->block_rsv = &root->fs_info->delalloc_block_rsv;
-                        ret = btrfs_update_inode_fallback(trans, root, inode);
-                        if (ret) /* -ENOMEM or corruption */
-                                btrfs_abort_transaction(trans, root, ret);
+                btrfs_ordered_update_i_size(inode, 0, ordered_extent);
+                if (nolock)
+                        trans = btrfs_join_transaction_nolock(root);
+                else
+                        trans = btrfs_join_transaction(root);
+                if (IS_ERR(trans)) {
+                        ret = PTR_ERR(trans);
+                        trans = NULL;
+                        goto out;
                 }
+                trans->block_rsv = &root->fs_info->delalloc_block_rsv;
+                ret = btrfs_update_inode_fallback(trans, root, inode);
+                if (ret) /* -ENOMEM or corruption */
+                        btrfs_abort_transaction(trans, root, ret);
                 goto out;
         }
 
@@ -1931,15 +1984,11 @@ static int btrfs_finish_ordered_io(struct btrfs_ordered_extent *ordered_extent)
         add_pending_csums(trans, inode, ordered_extent->file_offset,
                           &ordered_extent->list);
 
-        ret = btrfs_ordered_update_i_size(inode, 0, ordered_extent);
-        if (!ret || !test_bit(BTRFS_ORDERED_PREALLOC, &ordered_extent->flags)) {
-                ret = btrfs_update_inode_fallback(trans, root, inode);
-                if (ret) { /* -ENOMEM or corruption */
-                        btrfs_abort_transaction(trans, root, ret);
-                        goto out_unlock;
-                }
-        } else {
-                btrfs_set_inode_last_trans(trans, inode);
+        btrfs_ordered_update_i_size(inode, 0, ordered_extent);
+        ret = btrfs_update_inode_fallback(trans, root, inode);
+        if (ret) { /* -ENOMEM or corruption */
+                btrfs_abort_transaction(trans, root, ret);
+                goto out_unlock;
         }
         ret = 0;
 out_unlock:
@@ -2429,6 +2478,18 @@ int btrfs_orphan_cleanup(struct btrfs_root *root)
                                 continue;
                         }
                         nr_truncate++;
+
+                        /* 1 for the orphan item deletion. */
+                        trans = btrfs_start_transaction(root, 1);
+                        if (IS_ERR(trans)) {
+                                ret = PTR_ERR(trans);
+                                goto out;
+                        }
+                        ret = btrfs_orphan_add(trans, inode);
+                        btrfs_end_transaction(trans, root);
+                        if (ret)
+                                goto out;
+
                         ret = btrfs_truncate(inode);
                 } else {
                         nr_unlink++;
@@ -3074,7 +3135,6 @@ static int btrfs_unlink(struct inode *dir, struct dentry *dentry)
         struct btrfs_trans_handle *trans;
         struct inode *inode = dentry->d_inode;
         int ret;
-        unsigned long nr = 0;
 
         trans = __unlink_start_trans(dir, dentry);
         if (IS_ERR(trans))
@@ -3094,9 +3154,8 @@ static int btrfs_unlink(struct inode *dir, struct dentry *dentry)
         }
 
 out:
-        nr = trans->blocks_used;
         __unlink_end_trans(trans, root);
-        btrfs_btree_balance_dirty(root, nr);
+        btrfs_btree_balance_dirty(root);
         return ret;
 }
 
@@ -3186,7 +3245,6 @@ static int btrfs_rmdir(struct inode *dir, struct dentry *dentry)
         int err = 0;
         struct btrfs_root *root = BTRFS_I(dir)->root;
         struct btrfs_trans_handle *trans;
-        unsigned long nr = 0;
 
         if (inode->i_size > BTRFS_EMPTY_DIR_SIZE)
                 return -ENOTEMPTY;
@@ -3215,9 +3273,8 @@ static int btrfs_rmdir(struct inode *dir, struct dentry *dentry)
         if (!err)
                 btrfs_i_size_write(inode, 0);
 out:
-        nr = trans->blocks_used;
         __unlink_end_trans(trans, root);
-        btrfs_btree_balance_dirty(root, nr);
+        btrfs_btree_balance_dirty(root);
 
         return err;
 }
@@ -3497,11 +3554,11 @@ int btrfs_truncate_page(struct inode *inode, loff_t from, loff_t len,
         if (ret)
                 goto out;
 
-        ret = -ENOMEM;
 again:
         page = find_or_create_page(mapping, index, mask);
         if (!page) {
                 btrfs_delalloc_release_space(inode, PAGE_CACHE_SIZE);
+                ret = -ENOMEM;
                 goto out;
         }
 
@@ -3550,7 +3607,6 @@ again:
                 goto out_unlock;
         }
 
-        ret = 0;
         if (offset != PAGE_CACHE_SIZE) {
                 if (!len)
                         len = PAGE_CACHE_SIZE - offset;
@@ -3621,6 +3677,7 @@ int btrfs_cont_expand(struct inode *inode, loff_t oldsize, loff_t size)
                                 block_end - cur_offset, 0);
                 if (IS_ERR(em)) {
                         err = PTR_ERR(em);
+                        em = NULL;
                         break;
                 }
                 last_byte = min(extent_map_end(em), block_end);
@@ -3668,6 +3725,7 @@ int btrfs_cont_expand(struct inode *inode, loff_t oldsize, loff_t size)
 
                         hole_em->block_start = EXTENT_MAP_HOLE;
                         hole_em->block_len = 0;
+                        hole_em->orig_block_len = 0;
                         hole_em->bdev = root->fs_info->fs_devices->latest_bdev;
                         hole_em->compress_type = BTRFS_COMPRESS_NONE;
                         hole_em->generation = trans->transid;
@@ -3703,16 +3761,27 @@ next:
         return err;
 }
 
-static int btrfs_setsize(struct inode *inode, loff_t newsize)
+static int btrfs_setsize(struct inode *inode, struct iattr *attr)
 {
         struct btrfs_root *root = BTRFS_I(inode)->root;
         struct btrfs_trans_handle *trans;
         loff_t oldsize = i_size_read(inode);
+        loff_t newsize = attr->ia_size;
+        int mask = attr->ia_valid;
         int ret;
 
         if (newsize == oldsize)
                 return 0;
 
+        /*
+         * The regular truncate() case without ATTR_CTIME and ATTR_MTIME is a
+         * special case where we need to update the times despite not having
+         * these flags set.  For all other operations the VFS set these flags
+         * explicitly if it wants a timestamp update.
+         */
+        if (newsize != oldsize && (!(mask & (ATTR_CTIME | ATTR_MTIME))))
+                inode->i_ctime = inode->i_mtime = current_fs_time(inode->i_sb);
+
         if (newsize > oldsize) {
                 truncate_pagecache(inode, oldsize, newsize);
                 ret = btrfs_cont_expand(inode, oldsize, newsize);
@@ -3738,9 +3807,34 @@ static int btrfs_setsize(struct inode *inode, loff_t newsize)
                         set_bit(BTRFS_INODE_ORDERED_DATA_CLOSE,
                                 &BTRFS_I(inode)->runtime_flags);
 
+                /*
+                 * 1 for the orphan item we're going to add
+                 * 1 for the orphan item deletion.
+                 */
+                trans = btrfs_start_transaction(root, 2);
+                if (IS_ERR(trans))
+                        return PTR_ERR(trans);
+
+                /*
+                 * We need to do this in case we fail at _any_ point during the
+                 * actual truncate.  Once we do the truncate_setsize we could
+                 * invalidate pages which forces any outstanding ordered io to
+                 * be instantly completed which will give us extents that need
+                 * to be truncated.  If we fail to get an orphan inode down we
+                 * could have left over extents that were never meant to live,
+                 * so we need to garuntee from this point on that everything
+                 * will be consistent.
+                 */
+                ret = btrfs_orphan_add(trans, inode);
+                btrfs_end_transaction(trans, root);
+                if (ret)
+                        return ret;
+
                 /* we don't support swapfiles, so vmtruncate shouldn't fail */
                 truncate_setsize(inode, newsize);
                 ret = btrfs_truncate(inode);
+                if (ret && inode->i_nlink)
+                        btrfs_orphan_del(NULL, inode);
         }
 
         return ret;
@@ -3760,7 +3854,7 @@ static int btrfs_setattr(struct dentry *dentry, struct iattr *attr)
                 return err;
 
         if (S_ISREG(inode->i_mode) && (attr->ia_valid & ATTR_SIZE)) {
-                err = btrfs_setsize(inode, attr->ia_size);
+                err = btrfs_setsize(inode, attr);
                 if (err)
                         return err;
         }
@@ -3783,7 +3877,6 @@ void btrfs_evict_inode(struct inode *inode)
         struct btrfs_root *root = BTRFS_I(inode)->root;
         struct btrfs_block_rsv *rsv, *global_rsv;
         u64 min_size = btrfs_calc_trunc_metadata_size(root, 1);
-        unsigned long nr;
         int ret;
 
         trace_btrfs_inode_evict(inode);
@@ -3829,7 +3922,8 @@ void btrfs_evict_inode(struct inode *inode)
          * inode item when doing the truncate.
          */
         while (1) {
-                ret = btrfs_block_rsv_refill_noflush(root, rsv, min_size);
+                ret = btrfs_block_rsv_refill(root, rsv, min_size,
+                                             BTRFS_RESERVE_FLUSH_LIMIT);
 
                 /*
                  * Try and steal from the global reserve since we will
@@ -3847,7 +3941,7 @@ void btrfs_evict_inode(struct inode *inode)
                         goto no_delete;
                 }
 
-                trans = btrfs_start_transaction_noflush(root, 1);
+                trans = btrfs_start_transaction_lflush(root, 1);
                 if (IS_ERR(trans)) {
                         btrfs_orphan_del(NULL, inode);
                         btrfs_free_block_rsv(root, rsv);
@@ -3864,10 +3958,9 @@ void btrfs_evict_inode(struct inode *inode)
                 ret = btrfs_update_inode(trans, root, inode);
                 BUG_ON(ret);
 
-                nr = trans->blocks_used;
                 btrfs_end_transaction(trans, root);
                 trans = NULL;
-                btrfs_btree_balance_dirty(root, nr);
+                btrfs_btree_balance_dirty(root);
         }
 
         btrfs_free_block_rsv(root, rsv);
@@ -3883,9 +3976,8 @@ void btrfs_evict_inode(struct inode *inode)
               root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID))
                 btrfs_return_ino(root, btrfs_ino(inode));
 
-        nr = trans->blocks_used;
         btrfs_end_transaction(trans, root);
-        btrfs_btree_balance_dirty(root, nr);
+        btrfs_btree_balance_dirty(root);
 no_delete:
         clear_inode(inode);
         return;
@@ -4219,16 +4311,7 @@ struct inode *btrfs_lookup_dentry(struct inode *dir, struct dentry *dentry)
         if (dentry->d_name.len > BTRFS_NAME_LEN)
                 return ERR_PTR(-ENAMETOOLONG);
 
-        if (unlikely(d_need_lookup(dentry))) {
-                memcpy(&location, dentry->d_fsdata, sizeof(struct btrfs_key));
-                kfree(dentry->d_fsdata);
-                dentry->d_fsdata = NULL;
-                /* This thing is hashed, drop it for now */
-                d_drop(dentry);
-        } else {
-                ret = btrfs_inode_by_name(dir, dentry, &location);
-        }
-
+        ret = btrfs_inode_by_name(dir, dentry, &location);
         if (ret < 0)
                 return ERR_PTR(ret);
 
@@ -4298,11 +4381,6 @@ static struct dentry *btrfs_lookup(struct inode *dir, struct dentry *dentry,
         struct dentry *ret;
 
         ret = d_splice_alias(btrfs_lookup_dentry(dir, dentry), dentry);
-        if (unlikely(d_need_lookup(dentry))) {
-                spin_lock(&dentry->d_lock);
-                dentry->d_flags &= ~DCACHE_NEED_LOOKUP;
-                spin_unlock(&dentry->d_lock);
-        }
         return ret;
 }
 
@@ -4775,8 +4853,7 @@ static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
         if (S_ISREG(mode)) {
                 if (btrfs_test_opt(root, NODATASUM))
                         BTRFS_I(inode)->flags |= BTRFS_INODE_NODATASUM;
-                if (btrfs_test_opt(root, NODATACOW) ||
-                    (BTRFS_I(dir)->flags & BTRFS_INODE_NODATACOW))
+                if (btrfs_test_opt(root, NODATACOW))
                         BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW;
         }
 
@@ -4842,7 +4919,7 @@ int btrfs_add_link(struct btrfs_trans_handle *trans,
         ret = btrfs_insert_dir_item(trans, root, name, name_len,
                                     parent_inode, &key,
                                     btrfs_inode_type(inode), index);
-        if (ret == -EEXIST)
+        if (ret == -EEXIST || ret == -EOVERFLOW)
                 goto fail_dir_item;
         else if (ret) {
                 btrfs_abort_transaction(trans, root, ret);
@@ -4897,7 +4974,6 @@ static int btrfs_mknod(struct inode *dir, struct dentry *dentry,
         int err;
         int drop_inode = 0;
         u64 objectid;
-        unsigned long nr = 0;
         u64 index = 0;
 
         if (!new_valid_dev(rdev))
@@ -4930,6 +5006,12 @@ static int btrfs_mknod(struct inode *dir, struct dentry *dentry,
                 goto out_unlock;
         }
 
+        err = btrfs_update_inode(trans, root, inode);
+        if (err) {
+                drop_inode = 1;
+                goto out_unlock;
+        }
+
         /*
         * If the active LSM wants to access the inode during
         * d_instantiate it needs these. Smack checks to see
@@ -4947,9 +5029,8 @@ static int btrfs_mknod(struct inode *dir, struct dentry *dentry,
                 d_instantiate(dentry, inode);
         }
 out_unlock:
-        nr = trans->blocks_used;
         btrfs_end_transaction(trans, root);
-        btrfs_btree_balance_dirty(root, nr);
+        btrfs_btree_balance_dirty(root);
         if (drop_inode) {
                 inode_dec_link_count(inode);
                 iput(inode);
@@ -4963,9 +5044,8 @@ static int btrfs_create(struct inode *dir, struct dentry *dentry,
         struct btrfs_trans_handle *trans;
         struct btrfs_root *root = BTRFS_I(dir)->root;
         struct inode *inode = NULL;
-        int drop_inode = 0;
+        int drop_inode_on_err = 0;
         int err;
-        unsigned long nr = 0;
         u64 objectid;
         u64 index = 0;
 
@@ -4989,12 +5069,15 @@ static int btrfs_create(struct inode *dir, struct dentry *dentry,
                 err = PTR_ERR(inode);
                 goto out_unlock;
         }
+        drop_inode_on_err = 1;
 
         err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
-        if (err) {
-                drop_inode = 1;
+        if (err)
+                goto out_unlock;
+
+        err = btrfs_update_inode(trans, root, inode);
+        if (err)
                 goto out_unlock;
-        }
 
         /*
         * If the active LSM wants to access the inode during
@@ -5007,21 +5090,20 @@ static int btrfs_create(struct inode *dir, struct dentry *dentry,
 
         err = btrfs_add_nondir(trans, dir, dentry, inode, 0, index);
         if (err)
-                drop_inode = 1;
-        else {
-                inode->i_mapping->a_ops = &btrfs_aops;
-                inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
-                BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
-                d_instantiate(dentry, inode);
-        }
+                goto out_unlock;
+
+        inode->i_mapping->a_ops = &btrfs_aops;
+        inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
+        BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
+        d_instantiate(dentry, inode);
+
 out_unlock:
-        nr = trans->blocks_used;
         btrfs_end_transaction(trans, root);
-        if (drop_inode) {
+        if (err && drop_inode_on_err) {
                 inode_dec_link_count(inode);
                 iput(inode);
         }
-        btrfs_btree_balance_dirty(root, nr);
+        btrfs_btree_balance_dirty(root);
         return err;
 }
 
@@ -5032,7 +5114,6 @@ static int btrfs_link(struct dentry *old_dentry, struct inode *dir,
         struct btrfs_root *root = BTRFS_I(dir)->root;
         struct inode *inode = old_dentry->d_inode;
         u64 index;
-        unsigned long nr = 0;
         int err;
         int drop_inode = 0;
 
@@ -5062,6 +5143,7 @@ static int btrfs_link(struct dentry *old_dentry, struct inode *dir,
         inode_inc_iversion(inode);
         inode->i_ctime = CURRENT_TIME;
         ihold(inode);
+        set_bit(BTRFS_INODE_COPY_EVERYTHING, &BTRFS_I(inode)->runtime_flags);
 
         err = btrfs_add_nondir(trans, dir, dentry, inode, 1, index);
 
@@ -5076,14 +5158,13 @@ static int btrfs_link(struct dentry *old_dentry, struct inode *dir,
                 btrfs_log_new_name(trans, inode, NULL, parent);
         }
 
-        nr = trans->blocks_used;
         btrfs_end_transaction(trans, root);
 fail:
         if (drop_inode) {
                 inode_dec_link_count(inode);
                 iput(inode);
         }
-        btrfs_btree_balance_dirty(root, nr);
+        btrfs_btree_balance_dirty(root);
         return err;
 }
 
@@ -5096,7 +5177,6 @@ static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
         int drop_on_err = 0;
         u64 objectid = 0;
         u64 index = 0;
-        unsigned long nr = 1;
 
         /*
          * 2 items for inode and ref
@@ -5142,11 +5222,10 @@ static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
         drop_on_err = 0;
 
 out_fail:
-        nr = trans->blocks_used;
         btrfs_end_transaction(trans, root);
         if (drop_on_err)
                 iput(inode);
-        btrfs_btree_balance_dirty(root, nr);
+        btrfs_btree_balance_dirty(root);
         return err;
 }
 
@@ -5340,6 +5419,7 @@ again:
                 if (start + len <= found_key.offset)
                         goto not_found;
                 em->start = start;
+                em->orig_start = start;
                 em->len = found_key.offset - start;
                 goto not_found_em;
         }
@@ -5350,6 +5430,8 @@ again:
                 em->len = extent_end - extent_start;
                 em->orig_start = extent_start -
                                  btrfs_file_extent_offset(leaf, item);
+                em->orig_block_len = btrfs_file_extent_disk_num_bytes(leaf,
+                                                                      item);
                 bytenr = btrfs_file_extent_disk_bytenr(leaf, item);
                 if (bytenr == 0) {
                         em->block_start = EXTENT_MAP_HOLE;
@@ -5359,8 +5441,7 @@ again:
                         set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
                         em->compress_type = compress_type;
                         em->block_start = bytenr;
-                        em->block_len = btrfs_file_extent_disk_num_bytes(leaf,
-                                                                         item);
+                        em->block_len = em->orig_block_len;
                 } else {
                         bytenr += btrfs_file_extent_offset(leaf, item);
                         em->block_start = bytenr;
@@ -5390,7 +5471,8 @@ again:
                 em->start = extent_start + extent_offset;
                 em->len = (copy_size + root->sectorsize - 1) &
                         ~((u64)root->sectorsize - 1);
-                em->orig_start = EXTENT_MAP_INLINE;
+                em->orig_block_len = em->len;
+                em->orig_start = em->start;
                 if (compress_type) {
                         set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
                         em->compress_type = compress_type;
@@ -5439,11 +5521,11 @@ again:
                                     extent_map_end(em) - 1, NULL, GFP_NOFS);
                 goto insert;
         } else {
-                printk(KERN_ERR "btrfs unknown found_type %d\n", found_type);
-                WARN_ON(1);
+                WARN(1, KERN_ERR "btrfs unknown found_type %d\n", found_type);
         }
 not_found:
         em->start = start;
+        em->orig_start = start;
         em->len = len;
 not_found_em:
         em->block_start = EXTENT_MAP_HOLE;
@@ -5539,10 +5621,13 @@ struct extent_map *btrfs_get_extent_fiemap(struct inode *inode, struct page *pag
                 return em;
         if (em) {
                 /*
-                 * if our em maps to a hole, there might
-                 * actually be delalloc bytes behind it
+                 * if our em maps to
+                 * -  a hole or
+                 * -  a pre-alloc extent,
+                 * there might actually be delalloc bytes behind it.
                  */
-                if (em->block_start != EXTENT_MAP_HOLE)
+                if (em->block_start != EXTENT_MAP_HOLE &&
+                    !test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
                         return em;
                 else
                         hole_em = em;
@@ -5624,6 +5709,8 @@ struct extent_map *btrfs_get_extent_fiemap(struct inode *inode, struct page *pag
                          */
                         em->block_start = hole_em->block_start;
                         em->block_len = hole_len;
+                        if (test_bit(EXTENT_FLAG_PREALLOC, &hole_em->flags))
+                                set_bit(EXTENT_FLAG_PREALLOC, &em->flags);
                 } else {
                         em->start = range_start;
                         em->len = found;
@@ -5645,38 +5732,19 @@ out:
 }
 
 static struct extent_map *btrfs_new_extent_direct(struct inode *inode,
-                                                  struct extent_map *em,
                                                   u64 start, u64 len)
 {
         struct btrfs_root *root = BTRFS_I(inode)->root;
         struct btrfs_trans_handle *trans;
-        struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
+        struct extent_map *em;
         struct btrfs_key ins;
         u64 alloc_hint;
         int ret;
-        bool insert = false;
-
-        /*
-         * Ok if the extent map we looked up is a hole and is for the exact
-         * range we want, there is no reason to allocate a new one, however if
-         * it is not right then we need to free this one and drop the cache for
-         * our range.
-         */
-        if (em->block_start != EXTENT_MAP_HOLE || em->start != start ||
-            em->len != len) {
-                free_extent_map(em);
-                em = NULL;
-                insert = true;
-                btrfs_drop_extent_cache(inode, start, start + len - 1, 0);
-        }
 
         trans = btrfs_join_transaction(root);
         if (IS_ERR(trans))
                 return ERR_CAST(trans);
 
-        if (start <= BTRFS_I(inode)->disk_i_size && len < 64 * 1024)
-                btrfs_add_inode_defrag(trans, inode);
-
         trans->block_rsv = &root->fs_info->delalloc_block_rsv;
 
         alloc_hint = get_extent_allocation_hint(inode, start, len);
@@ -5687,37 +5755,10 @@ static struct extent_map *btrfs_new_extent_direct(struct inode *inode,
                 goto out;
         }
 
-        if (!em) {
-                em = alloc_extent_map();
-                if (!em) {
-                        em = ERR_PTR(-ENOMEM);
-                        goto out;
-                }
-        }
-
-        em->start = start;
-        em->orig_start = em->start;
-        em->len = ins.offset;
-
-        em->block_start = ins.objectid;
-        em->block_len = ins.offset;
-        em->bdev = root->fs_info->fs_devices->latest_bdev;
-
-        /*
-         * We need to do this because if we're using the original em we searched
-         * for, we could have EXTENT_FLAG_VACANCY set, and we don't want that.
-         */
-        em->flags = 0;
-        set_bit(EXTENT_FLAG_PINNED, &em->flags);
-
-        while (insert) {
-                write_lock(&em_tree->lock);
-                ret = add_extent_mapping(em_tree, em);
-                write_unlock(&em_tree->lock);
-                if (ret != -EEXIST)
-                        break;
-                btrfs_drop_extent_cache(inode, start, start + em->len - 1, 0);
-        }
+        em = create_pinned_em(inode, start, ins.offset, start, ins.objectid,
+                              ins.offset, ins.offset, 0);
+        if (IS_ERR(em))
+                goto out;
 
         ret = btrfs_add_ordered_extent_dio(inode, start, ins.objectid,
                                            ins.offset, ins.offset, 0);
@@ -5894,7 +5935,7 @@ static int lock_extent_direct(struct inode *inode, u64 lockstart, u64 lockend,
 static struct extent_map *create_pinned_em(struct inode *inode, u64 start,
                                            u64 len, u64 orig_start,
                                            u64 block_start, u64 block_len,
-                                           int type)
+                                           u64 orig_block_len, int type)
 {
         struct extent_map_tree *em_tree;
         struct extent_map *em;
@@ -5912,15 +5953,20 @@ static struct extent_map *create_pinned_em(struct inode *inode, u64 start,
         em->block_len = block_len;
         em->block_start = block_start;
         em->bdev = root->fs_info->fs_devices->latest_bdev;
+        em->orig_block_len = orig_block_len;
+        em->generation = -1;
         set_bit(EXTENT_FLAG_PINNED, &em->flags);
         if (type == BTRFS_ORDERED_PREALLOC)
-                set_bit(EXTENT_FLAG_PREALLOC, &em->flags);
+                set_bit(EXTENT_FLAG_FILLING, &em->flags);
 
         do {
                 btrfs_drop_extent_cache(inode, em->start,
                                 em->start + em->len - 1, 0);
                 write_lock(&em_tree->lock);
                 ret = add_extent_mapping(em_tree, em);
+                if (!ret)
+                        list_move(&em->list,
+                                  &em_tree->modified_extents);
                 write_unlock(&em_tree->lock);
         } while (ret == -EEXIST);
 
@@ -6047,13 +6093,15 @@ static int btrfs_get_blocks_direct(struct inode *inode, sector_t iblock,
                         goto must_cow;
 
                 if (can_nocow_odirect(trans, inode, start, len) == 1) {
-                        u64 orig_start = em->start;
+                        u64 orig_start = em->orig_start;
+                        u64 orig_block_len = em->orig_block_len;
 
                         if (type == BTRFS_ORDERED_PREALLOC) {
                                 free_extent_map(em);
                                 em = create_pinned_em(inode, start, len,
                                                        orig_start,
-                                                       block_start, len, type);
+                                                       block_start, len,
+                                                       orig_block_len, type);
                                 if (IS_ERR(em)) {
                                         btrfs_end_transaction(trans, root);
                                         goto unlock_err;
@@ -6077,7 +6125,8 @@ must_cow:
          * it above
          */
         len = bh_result->b_size;
-        em = btrfs_new_extent_direct(inode, em, start, len);
+        free_extent_map(em);
+        em = btrfs_new_extent_direct(inode, start, len);
         if (IS_ERR(em)) {
                 ret = PTR_ERR(em);
                 goto unlock_err;
@@ -6318,6 +6367,9 @@ static inline int __btrfs_submit_dio_bio(struct bio *bio, struct inode *inode,
         struct btrfs_root *root = BTRFS_I(inode)->root;
         int ret;
 
+        if (async_submit)
+                async_submit = !atomic_read(&BTRFS_I(inode)->sync_writers);
+
         bio_get(bio);
 
         if (!write) {
@@ -6362,7 +6414,6 @@ static int btrfs_submit_direct_hook(int rw, struct btrfs_dio_private *dip,
 {
         struct inode *inode = dip->inode;
         struct btrfs_root *root = BTRFS_I(inode)->root;
-        struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree;
         struct bio *bio;
         struct bio *orig_bio = dip->orig_bio;
         struct bio_vec *bvec = orig_bio->bi_io_vec;
@@ -6375,7 +6426,7 @@ static int btrfs_submit_direct_hook(int rw, struct btrfs_dio_private *dip,
         int async_submit = 0;
 
         map_length = orig_bio->bi_size;
-        ret = btrfs_map_block(map_tree, READ, start_sector << 9,
+        ret = btrfs_map_block(root->fs_info, READ, start_sector << 9,
                               &map_length, NULL, 0);
         if (ret) {
                 bio_put(orig_bio);
@@ -6429,7 +6480,8 @@ static int btrfs_submit_direct_hook(int rw, struct btrfs_dio_private *dip,
                         bio->bi_end_io = btrfs_end_dio_bio;
 
                         map_length = orig_bio->bi_size;
-                        ret = btrfs_map_block(map_tree, READ, start_sector << 9,
+                        ret = btrfs_map_block(root->fs_info, READ,
+                                              start_sector << 9,
                                               &map_length, NULL, 0);
                         if (ret) {
                                 bio_put(bio);
@@ -6582,9 +6634,17 @@ static ssize_t btrfs_direct_IO(int rw, struct kiocb *iocb,
                    btrfs_submit_direct, 0);
 }
 
+#define BTRFS_FIEMAP_FLAGS      (FIEMAP_FLAG_SYNC)
+
 static int btrfs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
                 __u64 start, __u64 len)
 {
+        int     ret;
+
+        ret = fiemap_check_flags(fieinfo, BTRFS_FIEMAP_FLAGS);
+        if (ret)
+                return ret;
+
         return extent_fiemap(inode, fieinfo, start, len, btrfs_get_extent_fiemap);
 }
 
@@ -6855,7 +6915,6 @@ static int btrfs_truncate(struct inode *inode)
         int ret;
         int err = 0;
         struct btrfs_trans_handle *trans;
-        unsigned long nr;
         u64 mask = root->sectorsize - 1;
         u64 min_size = btrfs_calc_trunc_metadata_size(root, 1);
 
@@ -6910,11 +6969,9 @@ static int btrfs_truncate(struct inode *inode)
 
         /*
          * 1 for the truncate slack space
-         * 1 for the orphan item we're going to add
-         * 1 for the orphan item deletion
          * 1 for updating the inode.
          */
-        trans = btrfs_start_transaction(root, 4);
+        trans = btrfs_start_transaction(root, 2);
         if (IS_ERR(trans)) {
                 err = PTR_ERR(trans);
                 goto out;
@@ -6925,12 +6982,6 @@ static int btrfs_truncate(struct inode *inode)
                                       min_size);
         BUG_ON(ret);
 
-        ret = btrfs_orphan_add(trans, inode);
-        if (ret) {
-                btrfs_end_transaction(trans, root);
-                goto out;
-        }
-
         /*
          * setattr is responsible for setting the ordered_data_close flag,
          * but that is only tested during the last file release.  That
@@ -6978,9 +7029,8 @@ static int btrfs_truncate(struct inode *inode)
                         break;
                 }
 
-                nr = trans->blocks_used;
                 btrfs_end_transaction(trans, root);
-                btrfs_btree_balance_dirty(root, nr);
+                btrfs_btree_balance_dirty(root);
 
                 trans = btrfs_start_transaction(root, 2);
                 if (IS_ERR(trans)) {
@@ -7000,12 +7050,6 @@ static int btrfs_truncate(struct inode *inode)
                 ret = btrfs_orphan_del(trans, inode);
                 if (ret)
                         err = ret;
-        } else if (ret && inode->i_nlink > 0) {
-                /*
-                 * Failed to do the truncate, remove us from the in memory
-                 * orphan list.
-                 */
-                ret = btrfs_orphan_del(NULL, inode);
         }
 
         if (trans) {
@@ -7014,9 +7058,8 @@ static int btrfs_truncate(struct inode *inode)
                 if (ret && !err)
                         err = ret;
 
-                nr = trans->blocks_used;
                 ret = btrfs_end_transaction(trans, root);
-                btrfs_btree_balance_dirty(root, nr);
+                btrfs_btree_balance_dirty(root);
         }
 
 out:
@@ -7093,6 +7136,7 @@ struct inode *btrfs_alloc_inode(struct super_block *sb)
         extent_io_tree_init(&ei->io_failure_tree, &inode->i_data);
         ei->io_tree.track_uptodate = 1;
         ei->io_failure_tree.track_uptodate = 1;
+        atomic_set(&ei->sync_writers, 0);
         mutex_init(&ei->log_mutex);
         mutex_init(&ei->delalloc_mutex);
         btrfs_ordered_inode_tree_init(&ei->ordered_tree);
@@ -7203,6 +7247,8 @@ void btrfs_destroy_cachep(void)
                 kmem_cache_destroy(btrfs_path_cachep);
         if (btrfs_free_space_cachep)
                 kmem_cache_destroy(btrfs_free_space_cachep);
+        if (btrfs_delalloc_work_cachep)
+                kmem_cache_destroy(btrfs_delalloc_work_cachep);
 }
 
 int btrfs_init_cachep(void)
@@ -7237,6 +7283,13 @@ int btrfs_init_cachep(void)
         if (!btrfs_free_space_cachep)
                 goto fail;
 
+        btrfs_delalloc_work_cachep = kmem_cache_create("btrfs_delalloc_work",
+                        sizeof(struct btrfs_delalloc_work), 0,
+                        SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD,
+                        NULL);
+        if (!btrfs_delalloc_work_cachep)
+                goto fail;
+
         return 0;
 fail:
         btrfs_destroy_cachep();
@@ -7308,6 +7361,28 @@ static int btrfs_rename(struct inode *old_dir, struct dentry *old_dentry,
         if (S_ISDIR(old_inode->i_mode) && new_inode &&
             new_inode->i_size > BTRFS_EMPTY_DIR_SIZE)
                 return -ENOTEMPTY;
+
+
+        /* check for collisions, even if the  name isn't there */
+        ret = btrfs_check_dir_item_collision(root, new_dir->i_ino,
+                             new_dentry->d_name.name,
+                             new_dentry->d_name.len);
+
+        if (ret) {
+                if (ret == -EEXIST) {
+                        /* we shouldn't get
+                         * eexist without a new_inode */
+                        if (!new_inode) {
+                                WARN_ON(1);
+                                return ret;
+                        }
+                } else {
+                        /* maybe -EOVERFLOW */
+                        return ret;
+                }
+        }
+        ret = 0;
+
         /*
          * we're using rename to replace one file with another.
          * and the replacement file is large.  Start IO on it now so
@@ -7447,39 +7522,110 @@ out_notrans:
         return ret;
 }
 
+static void btrfs_run_delalloc_work(struct btrfs_work *work)
+{
+        struct btrfs_delalloc_work *delalloc_work;
+
+        delalloc_work = container_of(work, struct btrfs_delalloc_work,
+                                     work);
+        if (delalloc_work->wait)
+                btrfs_wait_ordered_range(delalloc_work->inode, 0, (u64)-1);
+        else
+                filemap_flush(delalloc_work->inode->i_mapping);
+
+        if (delalloc_work->delay_iput)
+                btrfs_add_delayed_iput(delalloc_work->inode);
+        else
+                iput(delalloc_work->inode);
+        complete(&delalloc_work->completion);
+}
+
+struct btrfs_delalloc_work *btrfs_alloc_delalloc_work(struct inode *inode,
+                                                    int wait, int delay_iput)
+{
+        struct btrfs_delalloc_work *work;
+
+        work = kmem_cache_zalloc(btrfs_delalloc_work_cachep, GFP_NOFS);
+        if (!work)
+                return NULL;
+
+        init_completion(&work->completion);
+        INIT_LIST_HEAD(&work->list);
+        work->inode = inode;
+        work->wait = wait;
+        work->delay_iput = delay_iput;
+        work->work.func = btrfs_run_delalloc_work;
+
+        return work;
+}
+
+void btrfs_wait_and_free_delalloc_work(struct btrfs_delalloc_work *work)
+{
+        wait_for_completion(&work->completion);
+        kmem_cache_free(btrfs_delalloc_work_cachep, work);
+}
+
 /*
  * some fairly slow code that needs optimization. This walks the list
  * of all the inodes with pending delalloc and forces them to disk.
  */
 int btrfs_start_delalloc_inodes(struct btrfs_root *root, int delay_iput)
 {
-        struct list_head *head = &root->fs_info->delalloc_inodes;
         struct btrfs_inode *binode;
         struct inode *inode;
+        struct btrfs_delalloc_work *work, *next;
+        struct list_head works;
+        struct list_head splice;
+        int ret = 0;
 
         if (root->fs_info->sb->s_flags & MS_RDONLY)
                 return -EROFS;
 
+        INIT_LIST_HEAD(&works);
+        INIT_LIST_HEAD(&splice);
+again:
         spin_lock(&root->fs_info->delalloc_lock);
-        while (!list_empty(head)) {
-                binode = list_entry(head->next, struct btrfs_inode,
+        list_splice_init(&root->fs_info->delalloc_inodes, &splice);
+        while (!list_empty(&splice)) {
+                binode = list_entry(splice.next, struct btrfs_inode,
                                     delalloc_inodes);
+
+                list_del_init(&binode->delalloc_inodes);
+
                 inode = igrab(&binode->vfs_inode);
                 if (!inode)
-                        list_del_init(&binode->delalloc_inodes);
+                        continue;
+
+                list_add_tail(&binode->delalloc_inodes,
+                              &root->fs_info->delalloc_inodes);
                 spin_unlock(&root->fs_info->delalloc_lock);
-                if (inode) {
-                        filemap_flush(inode->i_mapping);
-                        if (delay_iput)
-                                btrfs_add_delayed_iput(inode);
-                        else
-                                iput(inode);
+
+                work = btrfs_alloc_delalloc_work(inode, 0, delay_iput);
+                if (unlikely(!work)) {
+                        ret = -ENOMEM;
+                        goto out;
                 }
+                list_add_tail(&work->list, &works);
+                btrfs_queue_worker(&root->fs_info->flush_workers,
+                                   &work->work);
+
                 cond_resched();
                 spin_lock(&root->fs_info->delalloc_lock);
         }
         spin_unlock(&root->fs_info->delalloc_lock);
 
+        list_for_each_entry_safe(work, next, &works, list) {
+                list_del_init(&work->list);
+                btrfs_wait_and_free_delalloc_work(work);
+        }
+
+        spin_lock(&root->fs_info->delalloc_lock);
+        if (!list_empty(&root->fs_info->delalloc_inodes)) {
+                spin_unlock(&root->fs_info->delalloc_lock);
+                goto again;
+        }
+        spin_unlock(&root->fs_info->delalloc_lock);
+
         /* the filemap_flush will queue IO into the worker threads, but
          * we have to make sure the IO is actually started and that
          * ordered extents get created before we return
@@ -7493,6 +7639,18 @@ int btrfs_start_delalloc_inodes(struct btrfs_root *root, int delay_iput)
         }
         atomic_dec(&root->fs_info->async_submit_draining);
         return 0;
+out:
+        list_for_each_entry_safe(work, next, &works, list) {
+                list_del_init(&work->list);
+                btrfs_wait_and_free_delalloc_work(work);
+        }
+
+        if (!list_empty_careful(&splice)) {
+                spin_lock(&root->fs_info->delalloc_lock);
+                list_splice_tail(&splice, &root->fs_info->delalloc_inodes);
+                spin_unlock(&root->fs_info->delalloc_lock);
+        }
+        return ret;
 }
 
 static int btrfs_symlink(struct inode *dir, struct dentry *dentry,
@@ -7512,7 +7670,6 @@ static int btrfs_symlink(struct inode *dir, struct dentry *dentry,
         unsigned long ptr;
         struct btrfs_file_extent_item *ei;
         struct extent_buffer *leaf;
-        unsigned long nr = 0;
 
         name_len = strlen(symname) + 1;
         if (name_len > BTRFS_MAX_INLINE_DATA_SIZE(root))
@@ -7610,13 +7767,12 @@ static int btrfs_symlink(struct inode *dir, struct dentry *dentry,
 out_unlock:
         if (!err)
                 d_instantiate(dentry, inode);
-        nr = trans->blocks_used;
         btrfs_end_transaction(trans, root);
         if (drop_inode) {
                 inode_dec_link_count(inode);
                 iput(inode);
         }
-        btrfs_btree_balance_dirty(root, nr);
+        btrfs_btree_balance_dirty(root);
         return err;
 }
 
@@ -7679,6 +7835,7 @@ static int __btrfs_prealloc_file_range(struct inode *inode, int mode,
                 em->len = ins.offset;
                 em->block_start = ins.objectid;
                 em->block_len = ins.offset;
+                em->orig_block_len = ins.offset;
                 em->bdev = root->fs_info->fs_devices->latest_bdev;
                 set_bit(EXTENT_FLAG_PREALLOC, &em->flags);
                 em->generation = trans->transid;