Btrfs: Index extent buffers in an rbtree
[sfrench/cifs-2.6.git] / fs / btrfs / inode.c
index b2251e27ac84c018c0278343c0042a2c4a472393..60852ada658ef860f2df29911dd7804912a6ca36 100644 (file)
@@ -43,6 +43,7 @@
 #include "ioctl.h"
 #include "print-tree.h"
 #include "volumes.h"
+#include "ordered-data.h"
 
 struct btrfs_iget_args {
        u64 ino;
@@ -109,44 +110,61 @@ static int cow_file_range(struct inode *inode, u64 start, u64 end)
        u64 num_bytes;
        u64 cur_alloc_size;
        u64 blocksize = root->sectorsize;
-       u64 orig_start = start;
        u64 orig_num_bytes;
        struct btrfs_key ins;
-       int ret;
+       struct extent_map *em;
+       struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
+       int ret = 0;
 
-       trans = btrfs_start_transaction(root, 1);
+       trans = btrfs_join_transaction(root, 1);
        BUG_ON(!trans);
        btrfs_set_trans_block_group(trans, inode);
 
        num_bytes = (end - start + blocksize) & ~(blocksize - 1);
        num_bytes = max(blocksize,  num_bytes);
-       ret = btrfs_drop_extents(trans, root, inode,
-                                start, start + num_bytes, start, &alloc_hint);
        orig_num_bytes = num_bytes;
 
        if (alloc_hint == EXTENT_MAP_INLINE)
                goto out;
 
        BUG_ON(num_bytes > btrfs_super_total_bytes(&root->fs_info->super_copy));
+       mutex_lock(&BTRFS_I(inode)->extent_mutex);
+       btrfs_drop_extent_cache(inode, start, start + num_bytes - 1);
+       mutex_unlock(&BTRFS_I(inode)->extent_mutex);
 
        while(num_bytes > 0) {
                cur_alloc_size = min(num_bytes, root->fs_info->max_extent);
-               ret = btrfs_alloc_extent(trans, root, cur_alloc_size,
-                                        root->sectorsize,
-                                        root->root_key.objectid,
-                                        trans->transid,
-                                        inode->i_ino, start, 0,
-                                        alloc_hint, (u64)-1, &ins, 1);
+               ret = btrfs_reserve_extent(trans, root, cur_alloc_size,
+                                          root->sectorsize, 0, 0,
+                                          (u64)-1, &ins, 1);
                if (ret) {
                        WARN_ON(1);
                        goto out;
                }
+               em = alloc_extent_map(GFP_NOFS);
+               em->start = start;
+               em->len = ins.offset;
+               em->block_start = ins.objectid;
+               em->bdev = root->fs_info->fs_devices->latest_bdev;
+               mutex_lock(&BTRFS_I(inode)->extent_mutex);
+               set_bit(EXTENT_FLAG_PINNED, &em->flags);
+               while(1) {
+                       spin_lock(&em_tree->lock);
+                       ret = add_extent_mapping(em_tree, em);
+                       spin_unlock(&em_tree->lock);
+                       if (ret != -EEXIST) {
+                               free_extent_map(em);
+                               break;
+                       }
+                       btrfs_drop_extent_cache(inode, start,
+                                               start + ins.offset - 1);
+               }
+               mutex_unlock(&BTRFS_I(inode)->extent_mutex);
+
                cur_alloc_size = ins.offset;
-               ret = btrfs_insert_file_extent(trans, root, inode->i_ino,
-                                              start, ins.objectid, ins.offset,
-                                              ins.offset, 0);
-               inode->i_blocks += ins.offset >> 9;
-               btrfs_check_file(root, inode);
+               ret = btrfs_add_ordered_extent(inode, start, ins.objectid,
+                                              ins.offset);
+               BUG_ON(ret);
                if (num_bytes < cur_alloc_size) {
                        printk("num_bytes %Lu cur_alloc %Lu\n", num_bytes,
                               cur_alloc_size);
@@ -156,10 +174,6 @@ static int cow_file_range(struct inode *inode, u64 start, u64 end)
                alloc_hint = ins.objectid + ins.offset;
                start += cur_alloc_size;
        }
-       btrfs_drop_extent_cache(inode, orig_start,
-                               orig_start + orig_num_bytes - 1);
-       btrfs_add_ordered_inode(inode);
-       btrfs_update_inode(trans, root, inode);
 out:
        btrfs_end_transaction(trans, root);
        return ret;
@@ -341,23 +355,11 @@ int __btrfs_submit_bio_hook(struct inode *inode, int rw, struct bio *bio,
                          int mirror_num)
 {
        struct btrfs_root *root = BTRFS_I(inode)->root;
-       struct btrfs_trans_handle *trans;
        int ret = 0;
-       char *sums = NULL;
-
-       ret = btrfs_csum_one_bio(root, bio, &sums);
-       BUG_ON(ret);
-
-       trans = btrfs_start_transaction(root, 1);
-
-       btrfs_set_trans_block_group(trans, inode);
-       btrfs_csum_file_blocks(trans, root, inode, bio, sums);
 
-       ret = btrfs_end_transaction(trans, root);
+       ret = btrfs_csum_one_bio(root, inode, bio);
        BUG_ON(ret);
 
-       kfree(sums);
-
        return btrfs_map_bio(root, rw, bio, mirror_num, 1);
 }
 
@@ -367,14 +369,10 @@ int btrfs_submit_bio_hook(struct inode *inode, int rw, struct bio *bio,
        struct btrfs_root *root = BTRFS_I(inode)->root;
        int ret = 0;
 
-       if (!(rw & (1 << BIO_RW))) {
-               ret = btrfs_bio_wq_end_io(root->fs_info, bio, 0);
-               BUG_ON(ret);
-               goto mapit;
-       }
+       ret = btrfs_bio_wq_end_io(root->fs_info, bio, 0);
+       BUG_ON(ret);
 
-       if (btrfs_test_opt(root, NODATASUM) ||
-           btrfs_test_flag(inode, NODATASUM)) {
+       if (!(rw & (1 << BIO_RW))) {
                goto mapit;
        }
 
@@ -385,6 +383,218 @@ mapit:
        return btrfs_map_bio(root, rw, bio, mirror_num, 0);
 }
 
+static noinline int add_pending_csums(struct btrfs_trans_handle *trans,
+                            struct inode *inode, u64 file_offset,
+                            struct list_head *list)
+{
+       struct list_head *cur;
+       struct btrfs_ordered_sum *sum;
+
+       btrfs_set_trans_block_group(trans, inode);
+       list_for_each(cur, list) {
+               sum = list_entry(cur, struct btrfs_ordered_sum, list);
+               mutex_lock(&BTRFS_I(inode)->csum_mutex);
+               btrfs_csum_file_blocks(trans, BTRFS_I(inode)->root,
+                                      inode, sum);
+               mutex_unlock(&BTRFS_I(inode)->csum_mutex);
+       }
+       return 0;
+}
+
+struct btrfs_writepage_fixup {
+       struct page *page;
+       struct btrfs_work work;
+};
+
+/* see btrfs_writepage_start_hook for details on why this is required */
+void btrfs_writepage_fixup_worker(struct btrfs_work *work)
+{
+       struct btrfs_writepage_fixup *fixup;
+       struct btrfs_ordered_extent *ordered;
+       struct page *page;
+       struct inode *inode;
+       u64 page_start;
+       u64 page_end;
+
+       fixup = container_of(work, struct btrfs_writepage_fixup, work);
+       page = fixup->page;
+again:
+       lock_page(page);
+       if (!page->mapping || !PageDirty(page) || !PageChecked(page)) {
+               ClearPageChecked(page);
+               goto out_page;
+       }
+
+       inode = page->mapping->host;
+       page_start = page_offset(page);
+       page_end = page_offset(page) + PAGE_CACHE_SIZE - 1;
+
+       lock_extent(&BTRFS_I(inode)->io_tree, page_start, page_end, GFP_NOFS);
+
+       /* already ordered? We're done */
+       if (test_range_bit(&BTRFS_I(inode)->io_tree, page_start, page_end,
+                            EXTENT_ORDERED, 0)) {
+               goto out;
+       }
+
+       ordered = btrfs_lookup_ordered_extent(inode, page_start);
+       if (ordered) {
+               unlock_extent(&BTRFS_I(inode)->io_tree, page_start,
+                             page_end, GFP_NOFS);
+               unlock_page(page);
+               btrfs_start_ordered_extent(inode, ordered, 1);
+               goto again;
+       }
+
+       set_extent_delalloc(&BTRFS_I(inode)->io_tree, page_start, page_end,
+                           GFP_NOFS);
+       ClearPageChecked(page);
+out:
+       unlock_extent(&BTRFS_I(inode)->io_tree, page_start, page_end, GFP_NOFS);
+out_page:
+       unlock_page(page);
+       page_cache_release(page);
+}
+
+/*
+ * There are a few paths in the higher layers of the kernel that directly
+ * set the page dirty bit without asking the filesystem if it is a
+ * good idea.  This causes problems because we want to make sure COW
+ * properly happens and the data=ordered rules are followed.
+ *
+ * In our case any range that doesn't have the EXTENT_ORDERED bit set
+ * hasn't been properly setup for IO.  We kick off an async process
+ * to fix it up.  The async helper will wait for ordered extents, set
+ * the delalloc bit and make it safe to write the page.
+ */
+int btrfs_writepage_start_hook(struct page *page, u64 start, u64 end)
+{
+       struct inode *inode = page->mapping->host;
+       struct btrfs_writepage_fixup *fixup;
+       struct btrfs_root *root = BTRFS_I(inode)->root;
+       int ret;
+
+       ret = test_range_bit(&BTRFS_I(inode)->io_tree, start, end,
+                            EXTENT_ORDERED, 0);
+       if (ret)
+               return 0;
+
+       if (PageChecked(page))
+               return -EAGAIN;
+
+       fixup = kzalloc(sizeof(*fixup), GFP_NOFS);
+       if (!fixup)
+               return -EAGAIN;
+printk("queueing worker to fixup page %lu %Lu\n", inode->i_ino, page_offset(page));
+       SetPageChecked(page);
+       page_cache_get(page);
+       fixup->work.func = btrfs_writepage_fixup_worker;
+       fixup->page = page;
+       btrfs_queue_worker(&root->fs_info->fixup_workers, &fixup->work);
+       return -EAGAIN;
+}
+
+static int btrfs_finish_ordered_io(struct inode *inode, u64 start, u64 end)
+{
+       struct btrfs_root *root = BTRFS_I(inode)->root;
+       struct btrfs_trans_handle *trans;
+       struct btrfs_ordered_extent *ordered_extent;
+       struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
+       struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
+       struct extent_map *em;
+       u64 alloc_hint = 0;
+       u64 clear_start;
+       u64 clear_end;
+       struct list_head list;
+       struct btrfs_key ins;
+       int ret;
+
+       ret = btrfs_dec_test_ordered_pending(inode, start, end - start + 1);
+       if (!ret)
+               return 0;
+
+       trans = btrfs_join_transaction(root, 1);
+
+       ordered_extent = btrfs_lookup_ordered_extent(inode, start);
+       BUG_ON(!ordered_extent);
+
+       lock_extent(io_tree, ordered_extent->file_offset,
+                   ordered_extent->file_offset + ordered_extent->len - 1,
+                   GFP_NOFS);
+
+       INIT_LIST_HEAD(&list);
+
+       ins.objectid = ordered_extent->start;
+       ins.offset = ordered_extent->len;
+       ins.type = BTRFS_EXTENT_ITEM_KEY;
+
+       ret = btrfs_alloc_reserved_extent(trans, root, root->root_key.objectid,
+                                         trans->transid, inode->i_ino,
+                                         ordered_extent->file_offset, &ins);
+       BUG_ON(ret);
+
+       mutex_lock(&BTRFS_I(inode)->extent_mutex);
+
+       ret = btrfs_drop_extents(trans, root, inode,
+                                ordered_extent->file_offset,
+                                ordered_extent->file_offset +
+                                ordered_extent->len,
+                                ordered_extent->file_offset, &alloc_hint);
+       BUG_ON(ret);
+       ret = btrfs_insert_file_extent(trans, root, inode->i_ino,
+                                      ordered_extent->file_offset,
+                                      ordered_extent->start,
+                                      ordered_extent->len,
+                                      ordered_extent->len, 0);
+       BUG_ON(ret);
+
+       spin_lock(&em_tree->lock);
+       clear_start = ordered_extent->file_offset;
+       clear_end = ordered_extent->file_offset + ordered_extent->len;
+       while(clear_start < clear_end) {
+               em = lookup_extent_mapping(em_tree, clear_start,
+                                          clear_end - clear_start);
+               if (em) {
+                       clear_bit(EXTENT_FLAG_PINNED, &em->flags);
+                       clear_start = em->start + em->len;
+                       free_extent_map(em);
+               } else {
+                       break;
+               }
+       }
+       spin_unlock(&em_tree->lock);
+
+       btrfs_drop_extent_cache(inode, ordered_extent->file_offset,
+                               ordered_extent->file_offset +
+                               ordered_extent->len - 1);
+       mutex_unlock(&BTRFS_I(inode)->extent_mutex);
+
+       inode->i_blocks += ordered_extent->len >> 9;
+       unlock_extent(io_tree, ordered_extent->file_offset,
+                   ordered_extent->file_offset + ordered_extent->len - 1,
+                   GFP_NOFS);
+       add_pending_csums(trans, inode, ordered_extent->file_offset,
+                         &ordered_extent->list);
+
+       btrfs_ordered_update_i_size(inode, ordered_extent);
+       btrfs_remove_ordered_extent(inode, ordered_extent);
+
+       /* once for us */
+       btrfs_put_ordered_extent(ordered_extent);
+       /* once for the tree */
+       btrfs_put_ordered_extent(ordered_extent);
+
+       btrfs_update_inode(trans, root, inode);
+       btrfs_end_transaction(trans, root);
+       return 0;
+}
+
+int btrfs_writepage_end_io_hook(struct page *page, u64 start, u64 end,
+                               struct extent_state *state, int uptodate)
+{
+       return btrfs_finish_ordered_io(page->mapping->host, start, end);
+}
+
 int btrfs_readpage_io_hook(struct page *page, u64 start, u64 end)
 {
        int ret = 0;
@@ -402,16 +612,30 @@ int btrfs_readpage_io_hook(struct page *page, u64 start, u64 end)
        path = btrfs_alloc_path();
        item = btrfs_lookup_csum(NULL, root, path, inode->i_ino, start, 0);
        if (IS_ERR(item)) {
+               /*
+                * It is possible there is an ordered extent that has
+                * not yet finished for this range in the file.  If so,
+                * that extent will have a csum cached, and it will insert
+                * the sum after all the blocks in the extent are fully
+                * on disk.  So, look for an ordered extent and use the
+                * sum if found.
+                */
+               ret = btrfs_find_ordered_sum(inode, start, &csum);
+               if (ret == 0)
+                       goto found;
+
                ret = PTR_ERR(item);
                /* a csum that isn't present is a preallocated region. */
                if (ret == -ENOENT || ret == -EFBIG)
                        ret = 0;
                csum = 0;
-               printk("no csum found for inode %lu start %Lu\n", inode->i_ino, start);
+               printk("no csum found for inode %lu start %Lu\n", inode->i_ino,
+                      start);
                goto out;
        }
        read_extent_buffer(path->nodes[0], &csum, (unsigned long)item,
                           BTRFS_CRC32_SIZE);
+found:
        set_state_private(io_tree, start, csum);
 out:
        if (path)
@@ -623,7 +847,7 @@ void btrfs_read_locked_inode(struct inode *inode)
        inode->i_nlink = btrfs_inode_nlink(leaf, inode_item);
        inode->i_uid = btrfs_inode_uid(leaf, inode_item);
        inode->i_gid = btrfs_inode_gid(leaf, inode_item);
-       inode->i_size = btrfs_inode_size(leaf, inode_item);
+       btrfs_i_size_write(inode, btrfs_inode_size(leaf, inode_item));
 
        tspec = btrfs_inode_atime(inode_item);
        inode->i_atime.tv_sec = btrfs_timespec_sec(leaf, tspec);
@@ -691,7 +915,7 @@ static void fill_inode_item(struct extent_buffer *leaf,
 {
        btrfs_set_inode_uid(leaf, item, inode->i_uid);
        btrfs_set_inode_gid(leaf, item, inode->i_gid);
-       btrfs_set_inode_size(leaf, item, inode->i_size);
+       btrfs_set_inode_size(leaf, item, BTRFS_I(inode)->disk_i_size);
        btrfs_set_inode_mode(leaf, item, inode->i_mode);
        btrfs_set_inode_nlink(leaf, item, inode->i_nlink);
 
@@ -718,7 +942,7 @@ static void fill_inode_item(struct extent_buffer *leaf,
                                    BTRFS_I(inode)->block_group->key.objectid);
 }
 
-int btrfs_update_inode(struct btrfs_trans_handle *trans,
+int noinline btrfs_update_inode(struct btrfs_trans_handle *trans,
                              struct btrfs_root *root,
                              struct inode *inode)
 {
@@ -813,7 +1037,7 @@ static int btrfs_unlink_trans(struct btrfs_trans_handle *trans,
 err:
        btrfs_free_path(path);
        if (!ret) {
-               dir->i_size -= name_len * 2;
+               btrfs_i_size_write(dir, dir->i_size - name_len * 2);
                dir->i_mtime = dir->i_ctime = CURRENT_TIME;
                btrfs_update_inode(trans, root, dir);
 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,18)
@@ -831,7 +1055,6 @@ static int btrfs_unlink(struct inode *dir, struct dentry *dentry)
 {
        struct btrfs_root *root;
        struct btrfs_trans_handle *trans;
-       struct inode *inode = dentry->d_inode;
        int ret;
        unsigned long nr = 0;
 
@@ -847,18 +1070,9 @@ static int btrfs_unlink(struct inode *dir, struct dentry *dentry)
        ret = btrfs_unlink_trans(trans, root, dir, dentry);
        nr = trans->blocks_used;
 
-       if (inode->i_nlink == 0) {
-               /* if the inode isn't linked anywhere,
-                * we don't need to worry about
-                * data=ordered
-                */
-               btrfs_del_ordered_inode(inode);
-       }
-
-       btrfs_end_transaction(trans, root);
+       btrfs_end_transaction_throttle(trans, root);
 fail:
        btrfs_btree_balance_dirty(root, nr);
-       btrfs_throttle(root);
        return ret;
 }
 
@@ -885,14 +1099,13 @@ static int btrfs_rmdir(struct inode *dir, struct dentry *dentry)
        /* now the directory is empty */
        err = btrfs_unlink_trans(trans, root, dir, dentry);
        if (!err) {
-               inode->i_size = 0;
+               btrfs_i_size_write(inode, 0);
        }
 
        nr = trans->blocks_used;
-       ret = btrfs_end_transaction(trans, root);
+       ret = btrfs_end_transaction_throttle(trans, root);
 fail:
        btrfs_btree_balance_dirty(root, nr);
-       btrfs_throttle(root);
 
        if (ret && !err)
                err = ret;
@@ -1117,34 +1330,6 @@ error:
        return ret;
 }
 
-static int btrfs_cow_one_page(struct inode *inode, struct page *page,
-                             size_t zero_start)
-{
-       char *kaddr;
-       struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
-       u64 page_start = (u64)page->index << PAGE_CACHE_SHIFT;
-       u64 page_end = page_start + PAGE_CACHE_SIZE - 1;
-       int ret = 0;
-
-       WARN_ON(!PageLocked(page));
-       set_page_extent_mapped(page);
-
-       lock_extent(io_tree, page_start, page_end, GFP_NOFS);
-       set_extent_delalloc(&BTRFS_I(inode)->io_tree, page_start,
-                           page_end, GFP_NOFS);
-
-       if (zero_start != PAGE_CACHE_SIZE) {
-               kaddr = kmap(page);
-               memset(kaddr + zero_start, 0, PAGE_CACHE_SIZE - zero_start);
-               flush_dcache_page(page);
-               kunmap(page);
-       }
-       set_page_dirty(page);
-       unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
-
-       return ret;
-}
-
 /*
  * taken from block_truncate_page, but does cow as it zeros out
  * any bytes left in the last page in the file.
@@ -1153,12 +1338,16 @@ static int btrfs_truncate_page(struct address_space *mapping, loff_t from)
 {
        struct inode *inode = mapping->host;
        struct btrfs_root *root = BTRFS_I(inode)->root;
+       struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
+       struct btrfs_ordered_extent *ordered;
+       char *kaddr;
        u32 blocksize = root->sectorsize;
        pgoff_t index = from >> PAGE_CACHE_SHIFT;
        unsigned offset = from & (PAGE_CACHE_SIZE-1);
        struct page *page;
        int ret = 0;
        u64 page_start;
+       u64 page_end;
 
        if ((offset & (blocksize - 1)) == 0)
                goto out;
@@ -1168,6 +1357,10 @@ again:
        page = grab_cache_page(mapping, index);
        if (!page)
                goto out;
+
+       page_start = page_offset(page);
+       page_end = page_start + PAGE_CACHE_SIZE - 1;
+
        if (!PageUptodate(page)) {
                ret = btrfs_readpage(NULL, page);
                lock_page(page);
@@ -1181,10 +1374,33 @@ again:
                        goto out;
                }
        }
-
-       page_start = (u64)page->index << PAGE_CACHE_SHIFT;
        wait_on_page_writeback(page);
-       ret = btrfs_cow_one_page(inode, page, offset);
+
+       lock_extent(io_tree, page_start, page_end, GFP_NOFS);
+       set_page_extent_mapped(page);
+
+       ordered = btrfs_lookup_ordered_extent(inode, page_start);
+       if (ordered) {
+               unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
+               unlock_page(page);
+               page_cache_release(page);
+               btrfs_start_ordered_extent(inode, ordered, 1);
+               btrfs_put_ordered_extent(ordered);
+               goto again;
+       }
+
+       set_extent_delalloc(&BTRFS_I(inode)->io_tree, page_start,
+                           page_end, GFP_NOFS);
+       ret = 0;
+       if (offset != PAGE_CACHE_SIZE) {
+               kaddr = kmap(page);
+               memset(kaddr + offset, 0, PAGE_CACHE_SIZE - offset);
+               flush_dcache_page(page);
+               kunmap(page);
+       }
+       ClearPageChecked(page);
+       set_page_dirty(page);
+       unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
 
        unlock_page(page);
        page_cache_release(page);
@@ -1222,11 +1438,13 @@ static int btrfs_setattr(struct dentry *dentry, struct iattr *attr)
 
                btrfs_truncate_page(inode->i_mapping, inode->i_size);
 
-               lock_extent(io_tree, hole_start, block_end - 1, GFP_NOFS);
                hole_size = block_end - hole_start;
+               btrfs_wait_ordered_range(inode, hole_start, hole_size);
+               lock_extent(io_tree, hole_start, block_end - 1, GFP_NOFS);
 
                trans = btrfs_start_transaction(root, 1);
                btrfs_set_trans_block_group(trans, inode);
+               mutex_lock(&BTRFS_I(inode)->extent_mutex);
                err = btrfs_drop_extents(trans, root, inode,
                                         hole_start, block_end, hole_start,
                                         &alloc_hint);
@@ -1240,6 +1458,7 @@ static int btrfs_setattr(struct dentry *dentry, struct iattr *attr)
                                                (u64)-1);
                        btrfs_check_file(root, inode);
                }
+               mutex_unlock(&BTRFS_I(inode)->extent_mutex);
                btrfs_end_transaction(trans, root);
                unlock_extent(io_tree, hole_start, block_end - 1, GFP_NOFS);
                if (err)
@@ -1262,8 +1481,9 @@ void btrfs_delete_inode(struct inode *inode)
        if (is_bad_inode(inode)) {
                goto no_delete;
        }
+       btrfs_wait_ordered_range(inode, 0, (u64)-1);
 
-       inode->i_size = 0;
+       btrfs_i_size_write(inode, 0);
        trans = btrfs_start_transaction(root, 1);
 
        btrfs_set_trans_block_group(trans, inode);
@@ -1276,14 +1496,12 @@ void btrfs_delete_inode(struct inode *inode)
 
        btrfs_end_transaction(trans, root);
        btrfs_btree_balance_dirty(root, nr);
-       btrfs_throttle(root);
        return;
 
 no_delete_lock:
        nr = trans->blocks_used;
        btrfs_end_transaction(trans, root);
        btrfs_btree_balance_dirty(root, nr);
-       btrfs_throttle(root);
 no_delete:
        clear_inode(inode);
 }
@@ -1399,12 +1617,15 @@ static int btrfs_init_locked_inode(struct inode *inode, void *p)
        inode->i_ino = args->ino;
        BTRFS_I(inode)->root = args->root;
        BTRFS_I(inode)->delalloc_bytes = 0;
+       BTRFS_I(inode)->disk_i_size = 0;
        extent_map_tree_init(&BTRFS_I(inode)->extent_tree, GFP_NOFS);
        extent_io_tree_init(&BTRFS_I(inode)->io_tree,
                             inode->i_mapping, GFP_NOFS);
        extent_io_tree_init(&BTRFS_I(inode)->io_failure_tree,
                             inode->i_mapping, GFP_NOFS);
-       atomic_set(&BTRFS_I(inode)->ordered_writeback, 0);
+       btrfs_ordered_inode_tree_init(&BTRFS_I(inode)->ordered_tree);
+       mutex_init(&BTRFS_I(inode)->csum_mutex);
+       mutex_init(&BTRFS_I(inode)->extent_mutex);
        return 0;
 }
 
@@ -1649,7 +1870,7 @@ int btrfs_write_inode(struct inode *inode, int wait)
        int ret = 0;
 
        if (wait) {
-               trans = btrfs_start_transaction(root, 1);
+               trans = btrfs_join_transaction(root, 1);
                btrfs_set_trans_block_group(trans, inode);
                ret = btrfs_commit_transaction(trans, root);
        }
@@ -1667,7 +1888,7 @@ void btrfs_dirty_inode(struct inode *inode)
        struct btrfs_root *root = BTRFS_I(inode)->root;
        struct btrfs_trans_handle *trans;
 
-       trans = btrfs_start_transaction(root, 1);
+       trans = btrfs_join_transaction(root, 1);
        btrfs_set_trans_block_group(trans, inode);
        btrfs_update_inode(trans, root, inode);
        btrfs_end_transaction(trans, root);
@@ -1705,8 +1926,11 @@ static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
                             inode->i_mapping, GFP_NOFS);
        extent_io_tree_init(&BTRFS_I(inode)->io_failure_tree,
                             inode->i_mapping, GFP_NOFS);
-       atomic_set(&BTRFS_I(inode)->ordered_writeback, 0);
+       btrfs_ordered_inode_tree_init(&BTRFS_I(inode)->ordered_tree);
+       mutex_init(&BTRFS_I(inode)->csum_mutex);
+       mutex_init(&BTRFS_I(inode)->extent_mutex);
        BTRFS_I(inode)->delalloc_bytes = 0;
+       BTRFS_I(inode)->disk_i_size = 0;
        BTRFS_I(inode)->root = root;
 
        if (mode & S_IFDIR)
@@ -1802,7 +2026,8 @@ static int btrfs_add_link(struct btrfs_trans_handle *trans,
                                             dentry->d_parent->d_inode->i_ino);
                }
                parent_inode = dentry->d_parent->d_inode;
-               parent_inode->i_size += dentry->d_name.len * 2;
+               btrfs_i_size_write(parent_inode, parent_inode->i_size +
+                                  dentry->d_name.len * 2);
                parent_inode->i_mtime = parent_inode->i_ctime = CURRENT_TIME;
                ret = btrfs_update_inode(trans, root,
                                         dentry->d_parent->d_inode);
@@ -1873,14 +2098,13 @@ static int btrfs_mknod(struct inode *dir, struct dentry *dentry,
        btrfs_update_inode_block_group(trans, dir);
 out_unlock:
        nr = trans->blocks_used;
-       btrfs_end_transaction(trans, root);
+       btrfs_end_transaction_throttle(trans, root);
 fail:
        if (drop_inode) {
                inode_dec_link_count(inode);
                iput(inode);
        }
        btrfs_btree_balance_dirty(root, nr);
-       btrfs_throttle(root);
        return err;
 }
 
@@ -1929,23 +2153,25 @@ static int btrfs_create(struct inode *dir, struct dentry *dentry,
                                     inode->i_mapping, GFP_NOFS);
                extent_io_tree_init(&BTRFS_I(inode)->io_failure_tree,
                                     inode->i_mapping, GFP_NOFS);
+               mutex_init(&BTRFS_I(inode)->csum_mutex);
+               mutex_init(&BTRFS_I(inode)->extent_mutex);
                BTRFS_I(inode)->delalloc_bytes = 0;
-               atomic_set(&BTRFS_I(inode)->ordered_writeback, 0);
+               BTRFS_I(inode)->disk_i_size = 0;
                BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
+               btrfs_ordered_inode_tree_init(&BTRFS_I(inode)->ordered_tree);
        }
        dir->i_sb->s_dirt = 1;
        btrfs_update_inode_block_group(trans, inode);
        btrfs_update_inode_block_group(trans, dir);
 out_unlock:
        nr = trans->blocks_used;
-       btrfs_end_transaction(trans, root);
+       btrfs_end_transaction_throttle(trans, root);
 fail:
        if (drop_inode) {
                inode_dec_link_count(inode);
                iput(inode);
        }
        btrfs_btree_balance_dirty(root, nr);
-       btrfs_throttle(root);
        return err;
 }
 
@@ -1987,14 +2213,13 @@ static int btrfs_link(struct dentry *old_dentry, struct inode *dir,
                drop_inode = 1;
 
        nr = trans->blocks_used;
-       btrfs_end_transaction(trans, root);
+       btrfs_end_transaction_throttle(trans, root);
 fail:
        if (drop_inode) {
                inode_dec_link_count(inode);
                iput(inode);
        }
        btrfs_btree_balance_dirty(root, nr);
-       btrfs_throttle(root);
        return err;
 }
 
@@ -2040,7 +2265,7 @@ static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
        inode->i_fop = &btrfs_dir_file_operations;
        btrfs_set_trans_block_group(trans, inode);
 
-       inode->i_size = 0;
+       btrfs_i_size_write(inode, 0);
        err = btrfs_update_inode(trans, root, inode);
        if (err)
                goto out_fail;
@@ -2057,76 +2282,29 @@ static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
 
 out_fail:
        nr = trans->blocks_used;
-       btrfs_end_transaction(trans, root);
+       btrfs_end_transaction_throttle(trans, root);
 
 out_unlock:
        if (drop_on_err)
                iput(inode);
        btrfs_btree_balance_dirty(root, nr);
-       btrfs_throttle(root);
        return err;
 }
 
 static int merge_extent_mapping(struct extent_map_tree *em_tree,
                                struct extent_map *existing,
-                               struct extent_map *em)
+                               struct extent_map *em,
+                               u64 map_start, u64 map_len)
 {
        u64 start_diff;
-       u64 new_end;
-       int ret = 0;
-       int real_blocks = existing->block_start < EXTENT_MAP_LAST_BYTE;
-
-       if (real_blocks && em->block_start >= EXTENT_MAP_LAST_BYTE)
-               goto invalid;
-
-       if (!real_blocks && em->block_start != existing->block_start)
-               goto invalid;
-
-       new_end = max(existing->start + existing->len, em->start + em->len);
-
-       if (existing->start >= em->start) {
-               if (em->start + em->len < existing->start)
-                       goto invalid;
-
-               start_diff = existing->start - em->start;
-               if (real_blocks && em->block_start + start_diff !=
-                   existing->block_start)
-                       goto invalid;
-
-               em->len = new_end - em->start;
-
-               remove_extent_mapping(em_tree, existing);
-               /* free for the tree */
-               free_extent_map(existing);
-               ret = add_extent_mapping(em_tree, em);
 
-       } else if (em->start > existing->start) {
-
-               if (existing->start + existing->len < em->start)
-                       goto invalid;
-
-               start_diff = em->start - existing->start;
-               if (real_blocks && existing->block_start + start_diff !=
-                   em->block_start)
-                       goto invalid;
-
-               remove_extent_mapping(em_tree, existing);
-               em->block_start = existing->block_start;
-               em->start = existing->start;
-               em->len = new_end - existing->start;
-               free_extent_map(existing);
-
-               ret = add_extent_mapping(em_tree, em);
-       } else {
-               goto invalid;
-       }
-       return ret;
-
-invalid:
-       printk("invalid extent map merge [%Lu %Lu %Lu] [%Lu %Lu %Lu]\n",
-              existing->start, existing->len, existing->block_start,
-              em->start, em->len, em->block_start);
-       return -EIO;
+       BUG_ON(map_start < em->start || map_start >= extent_map_end(em));
+       start_diff = map_start - em->start;
+       em->start = map_start;
+       em->len = map_len;
+       if (em->block_start < EXTENT_MAP_LAST_BYTE)
+               em->block_start += start_diff;
+       return add_extent_mapping(em_tree, em);
 }
 
 struct extent_map *btrfs_get_extent(struct inode *inode, struct page *page,
@@ -2173,10 +2351,9 @@ again:
                err = -ENOMEM;
                goto out;
        }
-
+       em->bdev = root->fs_info->fs_devices->latest_bdev;
        em->start = EXTENT_MAP_HOLE;
        em->len = (u64)-1;
-       em->bdev = root->fs_info->fs_devices->latest_bdev;
        ret = btrfs_lookup_file_extent(trans, root, path,
                                       objectid, start, trans != NULL);
        if (ret < 0) {
@@ -2280,7 +2457,7 @@ again:
                                free_extent_map(em);
                                em = NULL;
                                btrfs_release_path(root, path);
-                               trans = btrfs_start_transaction(root, 1);
+                               trans = btrfs_join_transaction(root, 1);
                                goto again;
                        }
                        write_extent_buffer(leaf, map + pg_offset, ptr,
@@ -2317,6 +2494,9 @@ insert:
         */
        if (ret == -EEXIST) {
                struct extent_map *existing;
+
+               ret = 0;
+
                existing = lookup_extent_mapping(em_tree, start, len);
                if (existing && (existing->start > start ||
                    existing->start + existing->len <= start)) {
@@ -2328,7 +2508,8 @@ insert:
                                                         em->len);
                        if (existing) {
                                err = merge_extent_mapping(em_tree, existing,
-                                                          em);
+                                                          em, start,
+                                                          root->sectorsize);
                                free_extent_map(existing);
                                if (err) {
                                        free_extent_map(em);
@@ -2344,6 +2525,7 @@ insert:
                } else {
                        free_extent_map(em);
                        em = existing;
+                       err = 0;
                }
        }
        spin_unlock(&em_tree->lock);
@@ -2351,8 +2533,9 @@ out:
        btrfs_free_path(path);
        if (trans) {
                ret = btrfs_end_transaction(trans, root);
-               if (!err)
+               if (!err) {
                        err = ret;
+               }
        }
        if (err) {
                free_extent_map(em);
@@ -2477,8 +2660,7 @@ btrfs_readpages(struct file *file, struct address_space *mapping,
        return extent_readpages(tree, mapping, pages, nr_pages,
                                btrfs_get_extent);
 }
-
-static int btrfs_releasepage(struct page *page, gfp_t gfp_flags)
+static int __btrfs_releasepage(struct page *page, gfp_t gfp_flags)
 {
        struct extent_io_tree *tree;
        struct extent_map_tree *map;
@@ -2488,7 +2670,6 @@ static int btrfs_releasepage(struct page *page, gfp_t gfp_flags)
        map = &BTRFS_I(page->mapping->host)->extent_tree;
        ret = try_release_extent_mapping(map, tree, page, gfp_flags);
        if (ret == 1) {
-               invalidate_extent_lru(tree, page_offset(page), PAGE_CACHE_SIZE);
                ClearPagePrivate(page);
                set_page_private(page, 0);
                page_cache_release(page);
@@ -2496,15 +2677,49 @@ static int btrfs_releasepage(struct page *page, gfp_t gfp_flags)
        return ret;
 }
 
+static int btrfs_releasepage(struct page *page, gfp_t gfp_flags)
+{
+       return __btrfs_releasepage(page, gfp_flags);
+}
+
 static void btrfs_invalidatepage(struct page *page, unsigned long offset)
 {
        struct extent_io_tree *tree;
+       struct btrfs_ordered_extent *ordered;
+       u64 page_start = page_offset(page);
+       u64 page_end = page_start + PAGE_CACHE_SIZE - 1;
 
+       wait_on_page_writeback(page);
        tree = &BTRFS_I(page->mapping->host)->io_tree;
-       extent_invalidatepage(tree, page, offset);
-       btrfs_releasepage(page, GFP_NOFS);
+       if (offset) {
+               btrfs_releasepage(page, GFP_NOFS);
+               return;
+       }
+
+       lock_extent(tree, page_start, page_end, GFP_NOFS);
+       ordered = btrfs_lookup_ordered_extent(page->mapping->host,
+                                          page_offset(page));
+       if (ordered) {
+               /*
+                * IO on this page will never be started, so we need
+                * to account for any ordered extents now
+                */
+               clear_extent_bit(tree, page_start, page_end,
+                                EXTENT_DIRTY | EXTENT_DELALLOC |
+                                EXTENT_LOCKED, 1, 0, GFP_NOFS);
+               btrfs_finish_ordered_io(page->mapping->host,
+                                       page_start, page_end);
+               btrfs_put_ordered_extent(ordered);
+               lock_extent(tree, page_start, page_end, GFP_NOFS);
+       }
+       clear_extent_bit(tree, page_start, page_end,
+                EXTENT_LOCKED | EXTENT_DIRTY | EXTENT_DELALLOC |
+                EXTENT_ORDERED,
+                1, 1, GFP_NOFS);
+       __btrfs_releasepage(page, GFP_NOFS);
+
+       ClearPageChecked(page);
        if (PagePrivate(page)) {
-               invalidate_extent_lru(tree, page_offset(page), PAGE_CACHE_SIZE);
                ClearPagePrivate(page);
                set_page_private(page, 0);
                page_cache_release(page);
@@ -2530,35 +2745,68 @@ int btrfs_page_mkwrite(struct vm_area_struct *vma, struct page *page)
 {
        struct inode *inode = fdentry(vma->vm_file)->d_inode;
        struct btrfs_root *root = BTRFS_I(inode)->root;
-       unsigned long end;
+       struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
+       struct btrfs_ordered_extent *ordered;
+       char *kaddr;
+       unsigned long zero_start;
        loff_t size;
        int ret;
        u64 page_start;
+       u64 page_end;
 
        ret = btrfs_check_free_space(root, PAGE_CACHE_SIZE, 0);
        if (ret)
                goto out;
 
        ret = -EINVAL;
-
+again:
        lock_page(page);
-       wait_on_page_writeback(page);
        size = i_size_read(inode);
-       page_start = (u64)page->index << PAGE_CACHE_SHIFT;
+       page_start = page_offset(page);
+       page_end = page_start + PAGE_CACHE_SIZE - 1;
 
        if ((page->mapping != inode->i_mapping) ||
-           (page_start > size)) {
+           (page_start >= size)) {
                /* page got truncated out from underneath us */
                goto out_unlock;
        }
+       wait_on_page_writeback(page);
+
+       lock_extent(io_tree, page_start, page_end, GFP_NOFS);
+       set_page_extent_mapped(page);
+
+       /*
+        * we can't set the delalloc bits if there are pending ordered
+        * extents.  Drop our locks and wait for them to finish
+        */
+       ordered = btrfs_lookup_ordered_extent(inode, page_start);
+       if (ordered) {
+               unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
+               unlock_page(page);
+               btrfs_start_ordered_extent(inode, ordered, 1);
+               btrfs_put_ordered_extent(ordered);
+               goto again;
+       }
+
+       set_extent_delalloc(&BTRFS_I(inode)->io_tree, page_start,
+                           page_end, GFP_NOFS);
+       ret = 0;
 
        /* page is wholly or partially inside EOF */
        if (page_start + PAGE_CACHE_SIZE > size)
-               end = size & ~PAGE_CACHE_MASK;
+               zero_start = size & ~PAGE_CACHE_MASK;
        else
-               end = PAGE_CACHE_SIZE;
+               zero_start = PAGE_CACHE_SIZE;
 
-       ret = btrfs_cow_one_page(inode, page, end);
+       if (zero_start != PAGE_CACHE_SIZE) {
+               kaddr = kmap(page);
+               memset(kaddr + zero_start, 0, PAGE_CACHE_SIZE - zero_start);
+               flush_dcache_page(page);
+               kunmap(page);
+       }
+       ClearPageChecked(page);
+       set_page_dirty(page);
+       unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
 
 out_unlock:
        unlock_page(page);
@@ -2572,6 +2820,7 @@ static void btrfs_truncate(struct inode *inode)
        int ret;
        struct btrfs_trans_handle *trans;
        unsigned long nr;
+       u64 mask = root->sectorsize - 1;
 
        if (!S_ISREG(inode->i_mode))
                return;
@@ -2579,9 +2828,11 @@ static void btrfs_truncate(struct inode *inode)
                return;
 
        btrfs_truncate_page(inode->i_mapping, inode->i_size);
+       btrfs_wait_ordered_range(inode, inode->i_size & (~mask), (u64)-1);
 
        trans = btrfs_start_transaction(root, 1);
        btrfs_set_trans_block_group(trans, inode);
+       btrfs_i_size_write(inode, inode->i_size);
 
        /* FIXME, add redo link to tree so we don't leak on crash */
        ret = btrfs_truncate_in_trans(trans, root, inode,
@@ -2589,10 +2840,9 @@ static void btrfs_truncate(struct inode *inode)
        btrfs_update_inode(trans, root, inode);
        nr = trans->blocks_used;
 
-       ret = btrfs_end_transaction(trans, root);
+       ret = btrfs_end_transaction_throttle(trans, root);
        BUG_ON(ret);
        btrfs_btree_balance_dirty(root, nr);
-       btrfs_throttle(root);
 }
 
 /*
@@ -2638,7 +2888,7 @@ int btrfs_create_subvol_root(struct btrfs_root *new_root,
        ret = btrfs_insert_inode_ref(trans, new_root, "..", 2, new_dirid,
                                     new_dirid);
        inode->i_nlink = 1;
-       inode->i_size = 0;
+       btrfs_i_size_write(inode, 0);
 
        return btrfs_update_inode(trans, new_root, inode);
 }
@@ -2666,15 +2916,28 @@ struct inode *btrfs_alloc_inode(struct super_block *sb)
        if (!ei)
                return NULL;
        ei->last_trans = 0;
-       ei->ordered_trans = 0;
+       btrfs_ordered_inode_tree_init(&ei->ordered_tree);
        return &ei->vfs_inode;
 }
 
 void btrfs_destroy_inode(struct inode *inode)
 {
+       struct btrfs_ordered_extent *ordered;
        WARN_ON(!list_empty(&inode->i_dentry));
        WARN_ON(inode->i_data.nrpages);
 
+       while(1) {
+               ordered = btrfs_lookup_first_ordered_extent(inode, (u64)-1);
+               if (!ordered)
+                       break;
+               else {
+                       printk("found ordered extent %Lu %Lu\n",
+                              ordered->file_offset, ordered->len);
+                       btrfs_remove_ordered_extent(inode, ordered);
+                       btrfs_put_ordered_extent(ordered);
+                       btrfs_put_ordered_extent(ordered);
+               }
+       }
        btrfs_drop_extent_cache(inode, 0, (u64)-1);
        kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode));
 }
@@ -2871,9 +3134,12 @@ static int btrfs_symlink(struct inode *dir, struct dentry *dentry,
                                     inode->i_mapping, GFP_NOFS);
                extent_io_tree_init(&BTRFS_I(inode)->io_failure_tree,
                                     inode->i_mapping, GFP_NOFS);
+               mutex_init(&BTRFS_I(inode)->csum_mutex);
+               mutex_init(&BTRFS_I(inode)->extent_mutex);
                BTRFS_I(inode)->delalloc_bytes = 0;
-               atomic_set(&BTRFS_I(inode)->ordered_writeback, 0);
+               BTRFS_I(inode)->disk_i_size = 0;
                BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
+               btrfs_ordered_inode_tree_init(&BTRFS_I(inode)->ordered_tree);
        }
        dir->i_sb->s_dirt = 1;
        btrfs_update_inode_block_group(trans, inode);
@@ -2907,24 +3173,28 @@ static int btrfs_symlink(struct inode *dir, struct dentry *dentry,
        inode->i_op = &btrfs_symlink_inode_operations;
        inode->i_mapping->a_ops = &btrfs_symlink_aops;
        inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
-       inode->i_size = name_len - 1;
+       btrfs_i_size_write(inode, name_len - 1);
        err = btrfs_update_inode(trans, root, inode);
        if (err)
                drop_inode = 1;
 
 out_unlock:
        nr = trans->blocks_used;
-       btrfs_end_transaction(trans, root);
+       btrfs_end_transaction_throttle(trans, root);
 out_fail:
        if (drop_inode) {
                inode_dec_link_count(inode);
                iput(inode);
        }
        btrfs_btree_balance_dirty(root, nr);
-       btrfs_throttle(root);
        return err;
 }
 
+static int btrfs_set_page_dirty(struct page *page)
+{
+       return __set_page_dirty_nobuffers(page);
+}
+
 static int btrfs_permission(struct inode *inode, int mask,
                            struct nameidata *nd)
 {
@@ -2971,6 +3241,8 @@ static struct extent_io_ops btrfs_extent_io_ops = {
        .merge_bio_hook = btrfs_merge_bio_hook,
        .readpage_io_hook = btrfs_readpage_io_hook,
        .readpage_end_io_hook = btrfs_readpage_end_io_hook,
+       .writepage_end_io_hook = btrfs_writepage_end_io_hook,
+       .writepage_start_hook = btrfs_writepage_start_hook,
        .readpage_io_failed_hook = btrfs_io_failed_hook,
        .set_bit_hook = btrfs_set_bit_hook,
        .clear_bit_hook = btrfs_clear_bit_hook,
@@ -2986,7 +3258,7 @@ static struct address_space_operations btrfs_aops = {
        .direct_IO      = btrfs_direct_IO,
        .invalidatepage = btrfs_invalidatepage,
        .releasepage    = btrfs_releasepage,
-       .set_page_dirty = __set_page_dirty_nobuffers,
+       .set_page_dirty = btrfs_set_page_dirty,
 };
 
 static struct address_space_operations btrfs_symlink_aops = {