NFS: cleanup of nfs_sync_inode_wait()

Allow callers to directly pass it a struct writeback_control.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

fs/nfs/file.c

@@ -307,11 +307,14 @@ static int nfs_commit_write(struct file *file, struct page *page, unsigned offse
 
 static void nfs_invalidate_page(struct page *page, unsigned long offset)
 {
-	struct inode *inode = page->mapping->host;
+	loff_t range_start, range_end;
 
+	if (offset != 0)
+		return;
 	/* Cancel any unstarted writes on this page */
-	if (offset == 0)
-		nfs_sync_inode_wait(inode, page->index, 1, FLUSH_INVALIDATE);
+	range_start = page_offset(page);
+	range_end = range_start + (loff_t)(PAGE_CACHE_SIZE - 1);
+	nfs_sync_mapping_range(page->mapping, range_start, range_end, FLUSH_INVALIDATE);
 }
 
 static int nfs_release_page(struct page *page, gfp_t gfp)

fs/nfs/inode.c

@@ -422,7 +422,7 @@ int nfs_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
 	int err;
 
 	/* Flush out writes to the server in order to update c/mtime */
-	nfs_sync_inode_wait(inode, 0, 0, FLUSH_NOCOMMIT);
+	nfs_sync_mapping_range(inode->i_mapping, 0, 0, FLUSH_NOCOMMIT);
 
 	/*
 	 * We may force a getattr if the user cares about atime.

fs/nfs/write.c

@@ -80,6 +80,7 @@ static struct nfs_page * nfs_update_request(struct nfs_open_context*,
 static int nfs_wait_on_write_congestion(struct address_space *, int);
 static int nfs_wait_on_requests(struct inode *, unsigned long, unsigned int);
 static long nfs_flush_mapping(struct address_space *mapping, struct writeback_control *wbc, int how);
+static int nfs_wb_page_priority(struct inode *inode, struct page *page, int how);
 static const struct rpc_call_ops nfs_write_partial_ops;
 static const struct rpc_call_ops nfs_write_full_ops;
 static const struct rpc_call_ops nfs_commit_ops;
@@ -1476,29 +1477,38 @@ int nfs_commit_inode(struct inode *inode, int how)
 }
 #endif
 
-long nfs_sync_inode_wait(struct inode *inode, unsigned long idx_start,
-		unsigned int npages, int how)
+long nfs_sync_mapping_wait(struct address_space *mapping, struct writeback_control *wbc, int how)
 {
+	struct inode *inode = mapping->host;
 	struct nfs_inode *nfsi = NFS_I(inode);
-	struct address_space *mapping = inode->i_mapping;
-	struct writeback_control wbc = {
-		.bdi = mapping->backing_dev_info,
-		.sync_mode = WB_SYNC_ALL,
-		.nr_to_write = LONG_MAX,
-		.range_start = ((loff_t)idx_start) << PAGE_CACHE_SHIFT,
-		.range_end = ((loff_t)(idx_start + npages - 1)) << PAGE_CACHE_SHIFT,
-	};
+	unsigned long idx_start, idx_end;
+	unsigned int npages = 0;
 	LIST_HEAD(head);
 	int nocommit = how & FLUSH_NOCOMMIT;
 	long pages, ret;
 
+	/* FIXME */
+	if (wbc->range_cyclic)
+		idx_start = 0;
+	else {
+		idx_start = wbc->range_start >> PAGE_CACHE_SHIFT;
+		idx_end = wbc->range_end >> PAGE_CACHE_SHIFT;
+		if (idx_end > idx_start) {
+			unsigned long l_npages = 1 + idx_end - idx_start;
+			npages = l_npages;
+			if (sizeof(npages) != sizeof(l_npages) &&
+					(unsigned long)npages != l_npages)
+				npages = 0;
+		}
+	}
 	how &= ~FLUSH_NOCOMMIT;
 	spin_lock(&nfsi->req_lock);
 	do {
+		wbc->pages_skipped = 0;
 		ret = nfs_wait_on_requests_locked(inode, idx_start, npages);
 		if (ret != 0)
 			continue;
-		pages = nfs_scan_dirty(mapping, &wbc, &head);
+		pages = nfs_scan_dirty(mapping, wbc, &head);
 		if (pages != 0) {
 			spin_unlock(&nfsi->req_lock);
 			if (how & FLUSH_INVALIDATE) {
@@ -1509,11 +1519,16 @@ long nfs_sync_inode_wait(struct inode *inode, unsigned long idx_start,
 			spin_lock(&nfsi->req_lock);
 			continue;
 		}
+		if (wbc->pages_skipped != 0)
+			continue;
 		if (nocommit)
 			break;
 		pages = nfs_scan_commit(inode, &head, idx_start, npages);
-		if (pages == 0)
+		if (pages == 0) {
+			if (wbc->pages_skipped != 0)
+				continue;
 			break;
+		}
 		if (how & FLUSH_INVALIDATE) {
 			spin_unlock(&nfsi->req_lock);
 			nfs_cancel_commit_list(&head);
@@ -1530,6 +1545,60 @@ long nfs_sync_inode_wait(struct inode *inode, unsigned long idx_start,
 	return ret;
 }
 
+/*
+ * flush the inode to disk.
+ */
+int nfs_wb_all(struct inode *inode)
+{
+	struct address_space *mapping = inode->i_mapping;
+	struct writeback_control wbc = {
+		.bdi = mapping->backing_dev_info,
+		.sync_mode = WB_SYNC_ALL,
+		.nr_to_write = LONG_MAX,
+		.range_cyclic = 1,
+	};
+	int ret;
+
+	ret = nfs_sync_mapping_wait(mapping, &wbc, 0);
+	if (ret >= 0)
+		return 0;
+	return ret;
+}
+
+int nfs_sync_mapping_range(struct address_space *mapping, loff_t range_start, loff_t range_end, int how)
+{
+	struct writeback_control wbc = {
+		.bdi = mapping->backing_dev_info,
+		.sync_mode = WB_SYNC_ALL,
+		.nr_to_write = LONG_MAX,
+		.range_start = range_start,
+		.range_end = range_end,
+	};
+	int ret;
+
+	ret = nfs_sync_mapping_wait(mapping, &wbc, how);
+	if (ret >= 0)
+		return 0;
+	return ret;
+}
+
+static int nfs_wb_page_priority(struct inode *inode, struct page *page, int how)
+{
+	loff_t range_start = page_offset(page);
+	loff_t range_end = range_start + (loff_t)(PAGE_CACHE_SIZE - 1);
+
+	return nfs_sync_mapping_range(inode->i_mapping, range_start, range_end, how | FLUSH_STABLE);
+}
+
+/*
+ * Write back all requests on one page - we do this before reading it.
+ */
+int nfs_wb_page(struct inode *inode, struct page* page)
+{
+	return nfs_wb_page_priority(inode, page, 0);
+}
+
+
 int __init nfs_init_writepagecache(void)
 {
 	nfs_wdata_cachep = kmem_cache_create("nfs_write_data",

include/linux/nfs_fs.h

@@ -432,7 +432,10 @@ extern void nfs_writedata_release(void *);
  * Try to write back everything synchronously (but check the
  * return value!)
  */
-extern long nfs_sync_inode_wait(struct inode *, unsigned long, unsigned int, int);
+extern long nfs_sync_mapping_wait(struct address_space *, struct writeback_control *, int);
+extern int nfs_sync_mapping_range(struct address_space *, loff_t, loff_t, int);
+extern int nfs_wb_all(struct inode *inode);
+extern int nfs_wb_page(struct inode *inode, struct page* page);
 #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4)
 extern int  nfs_commit_inode(struct inode *, int);
 extern struct nfs_write_data *nfs_commit_alloc(void);
@@ -452,28 +455,6 @@ nfs_have_writebacks(struct inode *inode)
 	return NFS_I(inode)->npages != 0;
 }
 
-static inline int
-nfs_wb_all(struct inode *inode)
-{
-	int error = nfs_sync_inode_wait(inode, 0, 0, 0);
-	return (error < 0) ? error : 0;
-}
-
-/*
- * Write back all requests on one page - we do this before reading it.
- */
-static inline int nfs_wb_page_priority(struct inode *inode, struct page* page, int how)
-{
-	int error = nfs_sync_inode_wait(inode, page->index, 1,
-			how | FLUSH_STABLE);
-	return (error < 0) ? error : 0;
-}
-
-static inline int nfs_wb_page(struct inode *inode, struct page* page)
-{
-	return nfs_wb_page_priority(inode, page, 0);
-}
-
 /*
  * Allocate nfs_write_data structures
  */