NFS: Clean up write code...

The addition of nfs_page_mkwrite means that We should no longer need to
create requests inside nfs_writepage()

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

fs/nfs/file.c

@@ -339,7 +339,7 @@ static int nfs_launder_page(struct page *page)
 const struct address_space_operations nfs_file_aops = {
 	.readpage = nfs_readpage,
 	.readpages = nfs_readpages,
-	.set_page_dirty = nfs_set_page_dirty,
+	.set_page_dirty = __set_page_dirty_nobuffers,
 	.writepage = nfs_writepage,
 	.writepages = nfs_writepages,
 	.prepare_write = nfs_prepare_write,

fs/nfs/write.c

@@ -243,10 +243,7 @@ static void nfs_end_page_writeback(struct page *page)
 
 /*
  * Find an associated nfs write request, and prepare to flush it out
- * Returns 1 if there was no write request, or if the request was
+ * May return an error if the user signalled nfs_wait_on_request().
- * already tagged by nfs_set_page_dirty.Returns 0 if the request
- * was not tagged.
- * May also return an error if the user signalled nfs_wait_on_request().
  */
 static int nfs_page_async_flush(struct nfs_pageio_descriptor *pgio,
 				struct page *page)
@@ -261,7 +258,7 @@ static int nfs_page_async_flush(struct nfs_pageio_descriptor *pgio,
 		req = nfs_page_find_request_locked(page);
 		if (req == NULL) {
 			spin_unlock(&inode->i_lock);
-			return 1;
+			return 0;
 		}
 		if (nfs_lock_request_dontget(req))
 			break;
@@ -282,7 +279,7 @@ static int nfs_page_async_flush(struct nfs_pageio_descriptor *pgio,
 		spin_unlock(&inode->i_lock);
 		nfs_unlock_request(req);
 		nfs_pageio_complete(pgio);
-		return 1;
+		return 0;
 	}
 	if (nfs_set_page_writeback(page) != 0) {
 		spin_unlock(&inode->i_lock);
@@ -290,10 +287,9 @@ static int nfs_page_async_flush(struct nfs_pageio_descriptor *pgio,
 	}
 	radix_tree_tag_set(&nfsi->nfs_page_tree, req->wb_index,
 			NFS_PAGE_TAG_LOCKED);
-	ret = test_bit(PG_NEED_FLUSH, &req->wb_flags);
 	spin_unlock(&inode->i_lock);
 	nfs_pageio_add_request(pgio, req);
-	return ret;
+	return 0;
 }
 
 /*
@@ -302,9 +298,7 @@ static int nfs_page_async_flush(struct nfs_pageio_descriptor *pgio,
 static int nfs_writepage_locked(struct page *page, struct writeback_control *wbc)
 {
 	struct nfs_pageio_descriptor mypgio, *pgio;
-	struct nfs_open_context *ctx;
 	struct inode *inode = page->mapping->host;
-	unsigned offset;
 	int err;
 
 	nfs_inc_stats(inode, NFSIOS_VFSWRITEPAGE);
@@ -320,28 +314,7 @@ static int nfs_writepage_locked(struct page *page, struct writeback_control *wbc
 	nfs_pageio_cond_complete(pgio, page->index);
 
 	err = nfs_page_async_flush(pgio, page);
-	if (err <= 0)
-		goto out;
-	err = 0;
-	offset = nfs_page_length(page);
-	if (!offset)
-		goto out;
 
-	nfs_pageio_cond_complete(pgio, page->index);
-
-	ctx = nfs_find_open_context(inode, NULL, FMODE_WRITE);
-	if (ctx == NULL) {
-		err = -EBADF;
-		goto out;
-	}
-	err = nfs_writepage_setup(ctx, page, 0, offset);
-	put_nfs_open_context(ctx);
-	if (err != 0)
-		goto out;
-	err = nfs_page_async_flush(pgio, page);
-	if (err > 0)
-		err = 0;
-out:
 	if (!wbc->for_writepages)
 		nfs_pageio_complete(pgio);
 	return err;
@@ -395,8 +368,6 @@ static int nfs_inode_add_request(struct inode *inode, struct nfs_page *req)
 	}
 	SetPagePrivate(req->wb_page);
 	set_page_private(req->wb_page, (unsigned long)req);
-	if (PageDirty(req->wb_page))
-		set_bit(PG_NEED_FLUSH, &req->wb_flags);
 	nfsi->npages++;
 	kref_get(&req->wb_kref);
 	return 0;
@@ -416,8 +387,6 @@ static void nfs_inode_remove_request(struct nfs_page *req)
 	set_page_private(req->wb_page, 0);
 	ClearPagePrivate(req->wb_page);
 	radix_tree_delete(&nfsi->nfs_page_tree, req->wb_index);
-	if (test_and_clear_bit(PG_NEED_FLUSH, &req->wb_flags))
-		__set_page_dirty_nobuffers(req->wb_page);
 	nfsi->npages--;
 	if (!nfsi->npages) {
 		spin_unlock(&inode->i_lock);
@@ -1477,35 +1446,6 @@ int nfs_wb_page(struct inode *inode, struct page* page)
 	return nfs_wb_page_priority(inode, page, FLUSH_STABLE);
 }
 
-int nfs_set_page_dirty(struct page *page)
-{
-	struct address_space *mapping = page->mapping;
-	struct inode *inode;
-	struct nfs_page *req;
-	int ret;
-
-	if (!mapping)
-		goto out_raced;
-	inode = mapping->host;
-	if (!inode)
-		goto out_raced;
-	spin_lock(&inode->i_lock);
-	req = nfs_page_find_request_locked(page);
-	if (req != NULL) {
-		/* Mark any existing write requests for flushing */
-		ret = !test_and_set_bit(PG_NEED_FLUSH, &req->wb_flags);
-		spin_unlock(&inode->i_lock);
-		nfs_release_request(req);
-		return ret;
-	}
-	ret = __set_page_dirty_nobuffers(page);
-	spin_unlock(&inode->i_lock);
-	return ret;
-out_raced:
-	return !TestSetPageDirty(page);
-}
-
-
 int __init nfs_init_writepagecache(void)
 {
 	nfs_wdata_cachep = kmem_cache_create("nfs_write_data",

include/linux/nfs_fs.h

@@ -420,7 +420,6 @@ extern int  nfs_flush_incompatible(struct file *file, struct page *page);
 extern int  nfs_updatepage(struct file *, struct page *, unsigned int, unsigned int);
 extern int nfs_writeback_done(struct rpc_task *, struct nfs_write_data *);
 extern void nfs_writedata_release(void *);
-extern int nfs_set_page_dirty(struct page *);
 
 /*
  * Try to write back everything synchronously (but check the

include/linux/nfs_page.h

@@ -30,7 +30,6 @@
 #define PG_BUSY			0
 #define PG_NEED_COMMIT		1
 #define PG_NEED_RESCHED		2
-#define PG_NEED_FLUSH		3
 
 struct nfs_inode;
 struct nfs_page {