[PATCH 09/10] mm: remove __filemap_fdatawrite_range

[Christoph Hellwig <hch@lst.de>]

Use filemap_fdatawrite_range and filemap_fdatawrite_range_kick instead
of the low-level __filemap_fdatawrite_range that requires the caller
to know the internals of the writeback_control structure and remove
__filemap_fdatawrite_range now that it is trivial and only two callers
would be left.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 fs/fs-writeback.c       |  6 +++---
 fs/sync.c               | 11 +++++------
 include/linux/pagemap.h |  2 --
 mm/fadvise.c            |  3 +--
 mm/filemap.c            | 25 +++++++------------------
 5 files changed, 16 insertions(+), 31 deletions(-)

diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index 2b35e80037fe..8b002ab18103 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -807,9 +807,9 @@ static void wbc_attach_and_unlock_inode(struct writeback_control *wbc,
  * @wbc: writeback_control of interest
  * @inode: target inode
  *
- * This function is to be used by __filemap_fdatawrite_range(), which is an
- * alternative entry point into writeback code, and first ensures @inode is
- * associated with a bdi_writeback and attaches it to @wbc.
+ * This function is to be used by filemap_fdatawrite*(), which write back data
+ * from arbitrary threads instead of the main writeback thread to ensure @inode
+ * is associated with a bdi_writeback and attached to @wbc.
  */
 void wbc_attach_fdatawrite_inode(struct writeback_control *wbc,
 		struct inode *inode)
diff --git a/fs/sync.c b/fs/sync.c
index 2955cd4c77a3..6d8b04e04c3c 100644
--- a/fs/sync.c
+++ b/fs/sync.c
@@ -280,14 +280,13 @@ int sync_file_range(struct file *file, loff_t offset, loff_t nbytes,
 	}
 
 	if (flags & SYNC_FILE_RANGE_WRITE) {
-		int sync_mode = WB_SYNC_NONE;
-
 		if ((flags & SYNC_FILE_RANGE_WRITE_AND_WAIT) ==
 			     SYNC_FILE_RANGE_WRITE_AND_WAIT)
-			sync_mode = WB_SYNC_ALL;
-
-		ret = __filemap_fdatawrite_range(mapping, offset, endbyte,
-						 sync_mode);
+			ret = filemap_fdatawrite_range(mapping, offset,
+					endbyte);
+		else
+			ret = filemap_fdatawrite_range_kick(mapping, offset,
+					endbyte);
 		if (ret < 0)
 			goto out;
 	}
diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h
index 742ba1dd3990..664f23f2330a 100644
--- a/include/linux/pagemap.h
+++ b/include/linux/pagemap.h
@@ -55,8 +55,6 @@ static inline int filemap_fdatawait(struct address_space *mapping)
 bool filemap_range_has_page(struct address_space *, loff_t lstart, loff_t lend);
 int filemap_write_and_wait_range(struct address_space *mapping,
 		loff_t lstart, loff_t lend);
-int __filemap_fdatawrite_range(struct address_space *mapping,
-		loff_t start, loff_t end, int sync_mode);
 int filemap_fdatawrite_range(struct address_space *mapping,
 		loff_t start, loff_t end);
 int filemap_check_errors(struct address_space *mapping);
diff --git a/mm/fadvise.c b/mm/fadvise.c
index 588fe76c5a14..f1be619f0e58 100644
--- a/mm/fadvise.c
+++ b/mm/fadvise.c
@@ -111,8 +111,7 @@ int generic_fadvise(struct file *file, loff_t offset, loff_t len, int advice)
 		spin_unlock(&file->f_lock);
 		break;
 	case POSIX_FADV_DONTNEED:
-		__filemap_fdatawrite_range(mapping, offset, endbyte,
-					   WB_SYNC_NONE);
+		filemap_fdatawrite_range_kick(mapping, offset, endbyte);
 
 		/*
 		 * First and last FULL page! Partial pages are deliberately
diff --git a/mm/filemap.c b/mm/filemap.c
index 26b692dbf091..ec19ed127de2 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -392,32 +392,23 @@ static int __filemap_fdatawrite(struct address_space *mapping, loff_t start,
 }
 
 /**
- * __filemap_fdatawrite_range - start writeback on mapping dirty pages in range
+ * filemap_fdatawrite_range - start writeback on mapping dirty pages in range
  * @mapping:	address space structure to write
  * @start:	offset in bytes where the range starts
  * @end:	offset in bytes where the range ends (inclusive)
- * @sync_mode:	enable synchronous operation
  *
  * Start writeback against all of a mapping's dirty pages that lie
  * within the byte offsets <start, end> inclusive.
  *
- * If sync_mode is WB_SYNC_ALL then this is a "data integrity" operation, as
- * opposed to a regular memory cleansing writeback.  The difference between
- * these two operations is that if a dirty page/buffer is encountered, it must
- * be waited upon, and not just skipped over.
+ * This is a data integrity operation that waits upon dirty or in writeback
+ * pages.
  *
  * Return: %0 on success, negative error code otherwise.
  */
-int __filemap_fdatawrite_range(struct address_space *mapping, loff_t start,
-				loff_t end, int sync_mode)
-{
-	return __filemap_fdatawrite(mapping, start, end, sync_mode, NULL);
-}
-
 int filemap_fdatawrite_range(struct address_space *mapping, loff_t start,
 		loff_t end)
 {
-	return __filemap_fdatawrite_range(mapping, start, end, WB_SYNC_ALL);
+	return __filemap_fdatawrite(mapping, start, end, WB_SYNC_ALL, NULL);
 }
 EXPORT_SYMBOL(filemap_fdatawrite_range);
 
@@ -441,7 +432,7 @@ EXPORT_SYMBOL(filemap_fdatawrite);
 int filemap_fdatawrite_range_kick(struct address_space *mapping, loff_t start,
 				  loff_t end)
 {
-	return __filemap_fdatawrite_range(mapping, start, end, WB_SYNC_NONE);
+	return __filemap_fdatawrite(mapping, start, end, WB_SYNC_NONE, NULL);
 }
 EXPORT_SYMBOL_GPL(filemap_fdatawrite_range_kick);
 
@@ -689,8 +680,7 @@ int filemap_write_and_wait_range(struct address_space *mapping,
 		return 0;
 
 	if (mapping_needs_writeback(mapping)) {
-		err = __filemap_fdatawrite_range(mapping, lstart, lend,
-						 WB_SYNC_ALL);
+		err = filemap_fdatawrite_range(mapping, lstart, lend);
 		/*
 		 * Even if the above returned error, the pages may be
 		 * written partially (e.g. -ENOSPC), so we wait for it.
@@ -792,8 +782,7 @@ int file_write_and_wait_range(struct file *file, loff_t lstart, loff_t lend)
 		return 0;
 
 	if (mapping_needs_writeback(mapping)) {
-		err = __filemap_fdatawrite_range(mapping, lstart, lend,
-						 WB_SYNC_ALL);
+		err = filemap_fdatawrite_range(mapping, lstart, lend);
 		/* See comment of filemap_write_and_wait() */
 		if (err != -EIO)
 			__filemap_fdatawait_range(mapping, lstart, lend);
-- 
2.47.3