8 files changed, 103 insertions, 2 deletions

diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 96a493217860..acf22ad6115c 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -1405,6 +1405,9 @@ int btrfs_csum_truncate(struct btrfs_trans_handle *trans,
                         struct btrfs_root *root, struct btrfs_path *path,
                         u64 isize);
 /* inode.c */
+int btrfs_merge_bio_hook(struct page *page, unsigned long offset,
+                         size_t size, struct bio *bio);
+
 static inline void dec_i_blocks(struct inode *inode, u64 dec)
 {
         dec = dec >> 9;
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 26185d46712c..4890151cd68d 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -1103,4 +1103,6 @@ int btrfs_read_buffer(struct extent_buffer *buf)
 static struct extent_io_ops btree_extent_io_ops = {
         .writepage_io_hook = btree_writepage_io_hook,
         .submit_bio_hook = btree_submit_bio_hook,
+        /* note we're sharing with inode.c for the merge bio hook */
+        .merge_bio_hook = btrfs_merge_bio_hook,
 };
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 14eb8fc87015..e9ef644ff56f 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -1473,13 +1473,31 @@ static int noinline find_free_extent(struct btrfs_trans_handle *trans,
         struct btrfs_root * root = orig_root->fs_info->extent_root;
         struct btrfs_fs_info *info = root->fs_info;
         u64 total_needed = num_bytes;
+        u64 *last_ptr = NULL;
         struct btrfs_block_group_cache *block_group;
         int full_scan = 0;
         int wrapped = 0;
+        int empty_cluster = 2 * 1024 * 1024;
 
         WARN_ON(num_bytes < root->sectorsize);
         btrfs_set_key_type(ins, BTRFS_EXTENT_ITEM_KEY);
 
+        if (data & BTRFS_BLOCK_GROUP_METADATA) {
+                last_ptr = &root->fs_info->last_alloc;
+        }
+
+        if ((data & BTRFS_BLOCK_GROUP_DATA) && btrfs_test_opt(root, SSD)) {
+                last_ptr = &root->fs_info->last_data_alloc;
+        }
+
+        if (last_ptr) {
+                if (*last_ptr)
+                        hint_byte = *last_ptr;
+                else {
+                        empty_size += empty_cluster;
+                }
+        }
+
         if (search_end == (u64)-1)
                 search_end = btrfs_super_total_bytes(&info->super_copy);
 
@@ -1489,11 +1507,14 @@ static int noinline find_free_extent(struct btrfs_trans_handle *trans,
                         hint_byte = search_start;
                 block_group = btrfs_find_block_group(root, block_group,
                                                      hint_byte, data, 1);
+                if (last_ptr && *last_ptr == 0 && block_group)
+                        hint_byte = block_group->key.objectid;
         } else {
                 block_group = btrfs_find_block_group(root,
                                                      trans->block_group,
                                                      search_start, data, 1);
         }
+        search_start = max(search_start, hint_byte);
 
         total_needed += empty_size;
 
@@ -1506,9 +1527,36 @@ check_failed:
         }
         ret = find_search_start(root, &block_group, &search_start,
                                 total_needed, data);
+        if (ret == -ENOSPC && last_ptr && *last_ptr) {
+                *last_ptr = 0;
+                block_group = btrfs_lookup_block_group(info,
+                                                       orig_search_start);
+                search_start = orig_search_start;
+                ret = find_search_start(root, &block_group, &search_start,
+                                        total_needed, data);
+        }
+        if (ret == -ENOSPC)
+                goto enospc;
         if (ret)
                 goto error;
 
+        if (last_ptr && *last_ptr && search_start != *last_ptr) {
+                *last_ptr = 0;
+                if (!empty_size) {
+                        empty_size += empty_cluster;
+                        total_needed += empty_size;
+                }
+                block_group = btrfs_lookup_block_group(info,
+                                                       orig_search_start);
+                search_start = orig_search_start;
+                ret = find_search_start(root, &block_group,
+                                        &search_start, total_needed, data);
+                if (ret == -ENOSPC)
+                        goto enospc;
+                if (ret)
+                        goto error;
+        }
+
         search_start = stripe_align(root, search_start);
         ins->objectid = search_start;
         ins->offset = num_bytes;
@@ -1547,6 +1595,13 @@ check_failed:
                         trans->block_group = block_group;
         }
         ins->offset = num_bytes;
+        if (last_ptr) {
+                *last_ptr = ins->objectid + ins->offset;
+                if (*last_ptr ==
+                    btrfs_super_total_bytes(&root->fs_info->super_copy)) {
+                        *last_ptr = 0;
+                }
+        }
         return 0;
 
 new_group:
@@ -1612,12 +1667,12 @@ int btrfs_alloc_extent(struct btrfs_trans_handle *trans,
         if (root->ref_cows) {
                 if (data != BTRFS_BLOCK_GROUP_METADATA) {
                         ret = do_chunk_alloc(trans, root->fs_info->extent_root,
-                                             num_bytes,
+                                             2 * 1024 * 1024,
                                              BTRFS_BLOCK_GROUP_METADATA);
                         BUG_ON(ret);
                 }
                 ret = do_chunk_alloc(trans, root->fs_info->extent_root,
-                                     num_bytes, data);
+                                     num_bytes + 2 * 1024 * 1024, data);
                 BUG_ON(ret);
         }
 
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 7e3a1ebde9fc..6dab664529c1 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -1730,6 +1730,8 @@ static int submit_extent_page(int rw, struct extent_io_tree *tree,
         if (bio_ret && *bio_ret) {
                 bio = *bio_ret;
                 if (bio->bi_sector + (bio->bi_size >> 9) != sector ||
+                    (tree->ops && tree->ops->merge_bio_hook &&
+                     tree->ops->merge_bio_hook(page, offset, size, bio)) ||
                     bio_add_page(bio, page, size, offset) < size) {
                         ret = submit_one_bio(rw, bio);
                         bio = NULL;
diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h
index 0dca89328f98..8b5319db2516 100644
--- a/fs/btrfs/extent_io.h
+++ b/fs/btrfs/extent_io.h
@@ -29,6 +29,8 @@ struct extent_io_ops {
         int (*fill_delalloc)(struct inode *inode, u64 start, u64 end);
         int (*writepage_io_hook)(struct page *page, u64 start, u64 end);
         int (*submit_bio_hook)(struct inode *inode, int rw, struct bio *bio);
+        int (*merge_bio_hook)(struct page *page, unsigned long offset,
+                              size_t size, struct bio *bio);
         int (*readpage_io_hook)(struct page *page, u64 start, u64 end);
         int (*readpage_end_io_hook)(struct page *page, u64 start, u64 end,
                                     struct extent_state *state);
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 109576b57f69..5140d6801846 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -296,6 +296,34 @@ int btrfs_clear_bit_hook(struct inode *inode, u64 start, u64 end,
         return 0;
 }
 
+int btrfs_merge_bio_hook(struct page *page, unsigned long offset,
+                         size_t size, struct bio *bio)
+{
+        struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
+        struct btrfs_mapping_tree *map_tree;
+        struct btrfs_device *dev;
+        u64 logical = bio->bi_sector << 9;
+        u64 physical;
+        u64 length = 0;
+        u64 map_length;
+        struct bio_vec *bvec;
+        int i;
+        int ret;
+
+        bio_for_each_segment(bvec, bio, i) {
+                length += bvec->bv_len;
+        }
+        map_tree = &root->fs_info->mapping_tree;
+        map_length = length;
+        ret = btrfs_map_block(map_tree, logical, &physical, &map_length, &dev);
+        if (map_length < length + size) {
+                printk("merge bio hook logical %Lu bio len %Lu physical %Lu "
+                       "len %Lu\n", logical, length, physical, map_length);
+                return 1;
+        }
+        return 0;
+}
+
 int btrfs_submit_bio_hook(struct inode *inode, int rw, struct bio *bio)
 {
         struct btrfs_root *root = BTRFS_I(inode)->root;
@@ -3033,6 +3061,7 @@ static struct file_operations btrfs_dir_file_operations = {
 static struct extent_io_ops btrfs_extent_io_ops = {
         .fill_delalloc = run_delalloc_range,
         .submit_bio_hook = btrfs_submit_bio_hook,
+        .merge_bio_hook = btrfs_merge_bio_hook,
         .readpage_io_hook = btrfs_readpage_io_hook,
         .readpage_end_io_hook = btrfs_readpage_end_io_hook,
         .set_bit_hook = btrfs_set_bit_hook,
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index ae22d01ecf54..16fb6bbe6e28 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -578,6 +578,11 @@ int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio)
         map_tree = &root->fs_info->mapping_tree;
         map_length = length;
         ret = btrfs_map_block(map_tree, logical, &physical, &map_length, &dev);
+        if (map_length < length) {
+                printk("mapping failed logical %Lu bio len %Lu physical %Lu "
+                       "len %Lu\n", logical, length, physical, map_length);
+                BUG();
+        }
         BUG_ON(map_length < length);
         bio->bi_sector = physical >> 9;
         bio->bi_bdev = dev->bdev;
diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h
index 77fa6efd79cf..20259128152e 100644
--- a/fs/btrfs/volumes.h
+++ b/fs/btrfs/volumes.h
@@ -64,4 +64,7 @@ void btrfs_mapping_init(struct btrfs_mapping_tree *tree);
 void btrfs_mapping_tree_free(struct btrfs_mapping_tree *tree);
 int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio);
 int btrfs_read_super_device(struct btrfs_root *root, struct extent_buffer *buf);
+int btrfs_map_block(struct btrfs_mapping_tree *map_tree,
+                    u64 logical, u64 *phys, u64 *length,
+                    struct btrfs_device **dev);
 #endif