jffs_file_write always appends to file.

[David Woodhouse <dwmw2@xxxxxxx.org>]

This patch makes it use the 'ppos' argument, but even with the addition of 
the jffs_delete_data() call, the filesystem needs to be remounted before 
the 'new' data appear in the right position.

 (... more stuff that might be fixed if we were using the page cache, 
methinks...)

I'm off home. Bob, if you want to take a look at this, feel free. This 
patch is all there is that I haven't committed to CVS. I posted my test 
program earlier, IIRC.

Index: inode-v22.c
===================================================================
RCS file: /home/cvs/mtd/fs/jffs/inode-v22.c,v
retrieving revision 1.14
diff -u -w -r1.14 inode-v22.c
--- inode-v22.c	2000/08/02 13:34:46	1.14
+++ inode-v22.c	2000/08/02 16:32:46
@@ -1459,7 +1459,7 @@
 	raw_inode.atime = CURRENT_TIME;
 	raw_inode.mtime = raw_inode.atime;
 	raw_inode.ctime = f->ctime;
-	raw_inode.offset = f->size;
+	raw_inode.offset = pos;
 	raw_inode.dsize = count;
 	raw_inode.rsize = 0;
 	raw_inode.nsize = 0;
@@ -1467,6 +1467,11 @@
 	raw_inode.spare = 0;
 	raw_inode.rename = 0;
 	raw_inode.deleted = 0;
+
+	if (pos < f->size) {
+		node->removed_size = raw_inode.rsize = jffs_min(count, f->size - pos);
+		jffs_delete_data(f, node);
+	}
 
 	/* TODO: BAAAAAAAAD! buf is a userspace-pointer, and should be
 	         treated as such, with copy_from_user etc...  */


--
dwmw2