fold do_sync_file_range into sys_sync_file_range

We recently go rid of all callers of do_sync_file_range as they're better
served with vfs_fsync or the filemap_write_and_wait.  Now that
do_sync_file_range is down to a single caller fold it into it so that people
don't start using it again accidentally.  While at it also switch it from
using __filemap_fdatawrite_range(..., WB_SYNC_ALL) to the more clear
filemap_fdatawrite_range().
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

fs/sync.c

@@ -355,6 +355,7 @@ SYSCALL_DEFINE(sync_file_range)(int fd, loff_t offset, loff_t nbytes,
 {
 	int ret;
 	struct file *file;
+	struct address_space *mapping;
 	loff_t endbyte;			/* inclusive */
 	int fput_needed;
 	umode_t i_mode;
@@ -405,7 +406,28 @@ SYSCALL_DEFINE(sync_file_range)(int fd, loff_t offset, loff_t nbytes,
 			!S_ISLNK(i_mode))
 		goto out_put;
 
-	ret = do_sync_mapping_range(file->f_mapping, offset, endbyte, flags);
+	mapping = file->f_mapping;
+	if (!mapping) {
+		ret = -EINVAL;
+		goto out_put;
+	}
+
+	ret = 0;
+	if (flags & SYNC_FILE_RANGE_WAIT_BEFORE) {
+		ret = filemap_fdatawait_range(mapping, offset, endbyte);
+		if (ret < 0)
+			goto out_put;
+	}
+
+	if (flags & SYNC_FILE_RANGE_WRITE) {
+		ret = filemap_fdatawrite_range(mapping, offset, endbyte);
+		if (ret < 0)
+			goto out_put;
+	}
+
+	if (flags & SYNC_FILE_RANGE_WAIT_AFTER)
+		ret = filemap_fdatawait_range(mapping, offset, endbyte);
+
 out_put:
 	fput_light(file, fput_needed);
 out:
@@ -437,38 +459,3 @@ asmlinkage long SyS_sync_file_range2(long fd, long flags,
 }
 SYSCALL_ALIAS(sys_sync_file_range2, SyS_sync_file_range2);
 #endif
-
-/*
- * `endbyte' is inclusive
- */
-int do_sync_mapping_range(struct address_space *mapping, loff_t offset,
-			  loff_t endbyte, unsigned int flags)
-{
-	int ret;
-
-	if (!mapping) {
-		ret = -EINVAL;
-		goto out;
-	}
-
-	ret = 0;
-	if (flags & SYNC_FILE_RANGE_WAIT_BEFORE) {
-		ret = filemap_fdatawait_range(mapping, offset, endbyte);
-		if (ret < 0)
-			goto out;
-	}
-
-	if (flags & SYNC_FILE_RANGE_WRITE) {
-		ret = __filemap_fdatawrite_range(mapping, offset, endbyte,
-						WB_SYNC_ALL);
-		if (ret < 0)
-			goto out;
-	}
-
-	if (flags & SYNC_FILE_RANGE_WAIT_AFTER) {
-		ret = filemap_fdatawait_range(mapping, offset, endbyte);
-	}
-out:
-	return ret;
-}
-EXPORT_SYMBOL_GPL(do_sync_mapping_range);

include/linux/fs.h

@@ -1095,10 +1095,6 @@ struct file_lock {
 
 extern void send_sigio(struct fown_struct *fown, int fd, int band);
 
-/* fs/sync.c */
-extern int do_sync_mapping_range(struct address_space *mapping, loff_t offset,
-			loff_t endbyte, unsigned int flags);
-
 #ifdef CONFIG_FILE_LOCKING
 extern int fcntl_getlk(struct file *, struct flock __user *);
 extern int fcntl_setlk(unsigned int, struct file *, unsigned int,