[JFFS2] Add support for JFFS2-on-Dataflash devices.

For Dataflash, can_mark_obsolete = false and the NAND write buffering
code (wbuf.c) is used.

Since the DataFlash chip will automatically erase pages when writing,
the cleanmarkers are not needed - so cleanmarker_oob = false and
cleanmarker_size = 0

DataFlash page-sizes are not a power of two (they're multiples of 528
bytes).  The SECTOR_ADDR macro (added in the previous core patch) is
replaced with a (slower) div/mod version if CONFIG_JFFS2_FS_DATAFLASH is
selected.

Signed-off-by: Andrew Victor <andrew@sanpeople.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

1 files changed, 10 insertions, 3 deletions

diff --git a/fs/jffs2/erase.c b/fs/jffs2/erase.c
index ae858f878875..a3c6cc150497 100644
--- a/fs/jffs2/erase.c
+++ b/fs/jffs2/erase.c
@@ -7,7 +7,7 @@
  *
  * For licensing information, see the file 'LICENCE' in this directory.
  *
- * $Id: erase.c,v 1.70 2005/02/09 09:09:01 pavlov Exp $
+ * $Id: erase.c,v 1.71 2005/02/09 09:17:40 pavlov Exp $
  *
  */
 
@@ -310,7 +310,7 @@ static void jffs2_mark_erased_block(struct jffs2_sb_info *c, struct jffs2_eraseb
         int ret;
         uint32_t bad_offset;
 
-        if (!jffs2_cleanmarker_oob(c)) {
+        if ((!jffs2_cleanmarker_oob(c)) && (c->cleanmarker_size > 0)) {
                 marker_ref = jffs2_alloc_raw_node_ref();
                 if (!marker_ref) {
                         printk(KERN_WARNING "Failed to allocate raw node ref for clean marker\n");
@@ -351,7 +351,7 @@ static void jffs2_mark_erased_block(struct jffs2_sb_info *c, struct jffs2_eraseb
                                         bad_offset += i;
                                         printk(KERN_WARNING "Newly-erased block contained word 0x%lx at offset 0x%08x\n", datum, bad_offset);
                                 bad: 
-                                        if (!jffs2_cleanmarker_oob(c))
+                                        if ((!jffs2_cleanmarker_oob(c)) && (c->cleanmarker_size > 0))
                                                 jffs2_free_raw_node_ref(marker_ref);
                                         kfree(ebuf);
                                 bad2:
@@ -387,6 +387,13 @@ static void jffs2_mark_erased_block(struct jffs2_sb_info *c, struct jffs2_eraseb
                 jeb->used_size = 0;
                 jeb->dirty_size = 0;
                 jeb->wasted_size = 0;
+        } else if (c->cleanmarker_size == 0) {
+                jeb->first_node = jeb->last_node = NULL;
+
+                jeb->free_size = c->sector_size;
+                jeb->used_size = 0;
+                jeb->dirty_size = 0;
+                jeb->wasted_size = 0;
         } else {
                 struct kvec vecs[1];
                 struct jffs2_unknown_node marker = {