Commit 6ea4843f authored by Tao Ma's avatar Tao Ma
Browse files

ocfs2: Add readhead during CoW. 



In CoW, when we meet with a readahead page, we know
it is time to move the readahead window. So carry
out a new readahead.

Signed-off-by: default avatarTao Ma <tao.ma@oracle.com>
parent 7b61cf54

fs/ocfs2/refcounttree.c

+14 −1
Original line number Diff line number Diff line
@@ -49,6 +49,7 @@ 


struct ocfs2_cow_context {

	struct inode *inode;

	struct file *file;

	u32 cow_start;

	u32 cow_len;

	struct ocfs2_extent_tree data_et;
@@ -2922,13 +2923,16 @@ static int ocfs2_duplicate_clusters_by_page(handle_t *handle, 
	u64 new_block = ocfs2_clusters_to_blocks(sb, new_cluster);

	struct page *page;

	pgoff_t page_index;

	unsigned int from, to;

	unsigned int from, to, readahead_pages;

	loff_t offset, end, map_end;

	struct address_space *mapping = context->inode->i_mapping;



	mlog(0, "old_cluster %u, new %u, len %u at offset %u\n", old_cluster,

	     new_cluster, new_len, cpos);



	readahead_pages =

		(ocfs2_cow_contig_clusters(sb) <<

		 OCFS2_SB(sb)->s_clustersize_bits) >> PAGE_CACHE_SHIFT;

	offset = ((loff_t)cpos) << OCFS2_SB(sb)->s_clustersize_bits;

	end = offset + (new_len << OCFS2_SB(sb)->s_clustersize_bits);

	/*
@@ -2959,6 +2963,14 @@ static int ocfs2_duplicate_clusters_by_page(handle_t *handle, 
		if (PAGE_CACHE_SIZE <= OCFS2_SB(sb)->s_clustersize)

			BUG_ON(PageDirty(page));



		if (PageReadahead(page) && context->file) {

			page_cache_async_readahead(mapping,

						   &context->file->f_ra,

						   context->file,

						   page, page_index,

						   readahead_pages);

		}



		if (!PageUptodate(page)) {

			ret = block_read_full_page(page, ocfs2_get_block);

			if (ret) {
@@ -3478,6 +3490,7 @@ static int ocfs2_refcount_cow_hunk(struct inode *inode, 
	context->ref_root_bh = ref_root_bh;

	context->cow_duplicate_clusters = ocfs2_duplicate_clusters_by_page;

	context->get_clusters = ocfs2_di_get_clusters;

	context->file = file;



	ocfs2_init_dinode_extent_tree(&context->data_et,

				      INODE_CACHE(inode), di_bh);