Btrfs: add rw argument to merge_bio_hook()

We'll want to merge writes so they can fill a full RAID[56] stripe, but
not necessarily reads.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>

5 files changed, 11 insertions, 11 deletions

diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c
index 94ab2f80e7e3..15b94089abc4 100644
--- a/fs/btrfs/compression.c
+++ b/fs/btrfs/compression.c
@@ -372,7 +372,7 @@ int btrfs_submit_compressed_write(struct inode *inode, u64 start,
                 page = compressed_pages[pg_index];
                 page->mapping = inode->i_mapping;
                 if (bio->bi_size)
-                        ret = io_tree->ops->merge_bio_hook(page, 0,
+                        ret = io_tree->ops->merge_bio_hook(WRITE, page, 0,
                                                            PAGE_CACHE_SIZE,
                                                            bio, 0);
                 else
@@ -655,7 +655,7 @@ int btrfs_submit_compressed_read(struct inode *inode, struct bio *bio,
                 page->index = em_start >> PAGE_CACHE_SHIFT;
 
                 if (comp_bio->bi_size)
-                        ret = tree->ops->merge_bio_hook(page, 0,
+                        ret = tree->ops->merge_bio_hook(READ, page, 0,
                                                         PAGE_CACHE_SIZE,
                                                         comp_bio, 0);
                 else
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 547b7b05727f..0ab51be6879f 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -3459,9 +3459,9 @@ int btrfs_writepages(struct address_space *mapping,
                      struct writeback_control *wbc);
 int btrfs_create_subvol_root(struct btrfs_trans_handle *trans,
                              struct btrfs_root *new_root, u64 new_dirid);
-int btrfs_merge_bio_hook(struct page *page, unsigned long offset,
-                         size_t size, struct bio *bio, unsigned long bio_flags);
-
+int btrfs_merge_bio_hook(int rw, struct page *page, unsigned long offset,
+                         size_t size, struct bio *bio,
+                         unsigned long bio_flags);
 int btrfs_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf);
 int btrfs_readpage(struct file *file, struct page *page);
 void btrfs_evict_inode(struct inode *inode);
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 1b319df29eee..86ecca48c604 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -2489,13 +2489,13 @@ static int __must_check submit_one_bio(int rw, struct bio *bio,
         return ret;
 }
 
-static int merge_bio(struct extent_io_tree *tree, struct page *page,
+static int merge_bio(int rw, struct extent_io_tree *tree, struct page *page,
                      unsigned long offset, size_t size, struct bio *bio,
                      unsigned long bio_flags)
 {
         int ret = 0;
         if (tree->ops && tree->ops->merge_bio_hook)
-                ret = tree->ops->merge_bio_hook(page, offset, size, bio,
+                ret = tree->ops->merge_bio_hook(rw, page, offset, size, bio,
                                                 bio_flags);
         BUG_ON(ret < 0);
         return ret;
@@ -2530,7 +2530,7 @@ static int submit_extent_page(int rw, struct extent_io_tree *tree,
                                 sector;
 
                 if (prev_bio_flags != bio_flags || !contig ||
-                    merge_bio(tree, page, offset, page_size, bio, bio_flags) ||
+                    merge_bio(rw, tree, page, offset, page_size, bio, bio_flags) ||
                     bio_add_page(bio, page, page_size, offset) < page_size) {
                         ret = submit_one_bio(rw, bio, mirror_num,
                                              prev_bio_flags);
diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h
index 2eacfabd3263..b14b36a80eba 100644
--- a/fs/btrfs/extent_io.h
+++ b/fs/btrfs/extent_io.h
@@ -72,7 +72,7 @@ struct extent_io_ops {
         int (*writepage_start_hook)(struct page *page, u64 start, u64 end);
         int (*writepage_io_hook)(struct page *page, u64 start, u64 end);
         extent_submit_bio_hook_t *submit_bio_hook;
-        int (*merge_bio_hook)(struct page *page, unsigned long offset,
+        int (*merge_bio_hook)(int rw, struct page *page, unsigned long offset,
                               size_t size, struct bio *bio,
                               unsigned long bio_flags);
         int (*readpage_io_hook)(struct page *page, u64 start, u64 end);
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 67ed24ae86bb..1b98c4ce3c6f 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -1566,7 +1566,7 @@ static void btrfs_clear_bit_hook(struct inode *inode,
  * extent_io.c merge_bio_hook, this must check the chunk tree to make sure
  * we don't create bios that span stripes or chunks
  */
-int btrfs_merge_bio_hook(struct page *page, unsigned long offset,
+int btrfs_merge_bio_hook(int rw, struct page *page, unsigned long offset,
                          size_t size, struct bio *bio,
                          unsigned long bio_flags)
 {
@@ -1581,7 +1581,7 @@ int btrfs_merge_bio_hook(struct page *page, unsigned long offset,
 
         length = bio->bi_size;
         map_length = length;
-        ret = btrfs_map_block(root->fs_info, READ, logical,
+        ret = btrfs_map_block(root->fs_info, rw, logical,
                               &map_length, NULL, 0);
         /* Will always return 0 with map_multi == NULL */
         BUG_ON(ret < 0);