reiserfs: get rid of AOP_FLAG_CONT_EXPAND flag

Remove usage of AOP_FLAG_CONT_EXPAND flag. Reiserfs is the only user of
it and it is easy to avoid.

Link: https://lore.kernel.org/r/20220220232219.1235-1-edward.shishkin@gmail.com
Signed-off-by: Edward Shishkin <edward.shishkin@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>

Author: edward6

fs/reiserfs/inode.c

@@ -2763,13 +2763,6 @@ static int reiserfs_write_begin(struct file *file,
 	int old_ref = 0;
 
  	inode = mapping->host;
-	*fsdata = NULL;
- 	if (flags & AOP_FLAG_CONT_EXPAND &&
- 	    (pos & (inode->i_sb->s_blocksize - 1)) == 0) {
- 		pos ++;
-		*fsdata = (void *)(unsigned long)flags;
-	}
-
 	index = pos >> PAGE_SHIFT;
 	page = grab_cache_page_write_begin(mapping, index, flags);
 	if (!page)
@@ -2896,9 +2889,6 @@ static int reiserfs_write_end(struct file *file, struct address_space *mapping,
 	unsigned start;
 	bool locked = false;
 
-	if ((unsigned long)fsdata & AOP_FLAG_CONT_EXPAND)
-		pos ++;
-
 	reiserfs_wait_on_write_block(inode->i_sb);
 	if (reiserfs_transaction_running(inode->i_sb))
 		th = current->journal_info;
@@ -3316,7 +3306,11 @@ int reiserfs_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
 
 		/* fill in hole pointers in the expanding truncate case. */
 		if (attr->ia_size > inode->i_size) {
-			error = generic_cont_expand_simple(inode, attr->ia_size);
+			loff_t pos = attr->ia_size;
+
+			if ((pos & (inode->i_sb->s_blocksize - 1)) == 0)
+				pos++;
+			error = generic_cont_expand_simple(inode, pos);
 			if (REISERFS_I(inode)->i_prealloc_count > 0) {
 				int err;
 				struct reiserfs_transaction_handle th;