[JFFS2] Switch to using an array of jffs2_raw_node_refs instead of a list.

This allows us to drop another pointer from the struct jffs2_raw_node_ref,
shrinking it to 8 bytes on 32-bit machines (if the TEST_TOTLEN) paranoia
check is turned off, which will be committed soon).

Signed-off-by: David Woodhouse <dwmw2@infradead.org>

1 files changed, 47 insertions, 46 deletions

diff --git a/fs/jffs2/nodelist.c b/fs/jffs2/nodelist.c
index 0e82979c741c..5d36e9b4d7c5 100644
--- a/fs/jffs2/nodelist.c
+++ b/fs/jffs2/nodelist.c
@@ -954,18 +954,16 @@ void jffs2_free_raw_node_refs(struct jffs2_sb_info *c)
 	for (i=0; i<c->nr_blocks; i++) {
 		this = c->blocks[i].first_node;
 		while (this) {
-			next = this->next_phys;
-			__jffs2_free_raw_node_ref(this);
+			if (this[REFS_PER_BLOCK].flash_offset == REF_LINK_NODE)
+				next = this[REFS_PER_BLOCK].next_in_ino;
+			else
+				next = NULL;
+
+			jffs2_free_refblock(this);
 			this = next;
 		}
 		c->blocks[i].first_node = c->blocks[i].last_node = NULL;
 	}
-	this = c->refs;
-	while (this) {
-		next = this->next_in_ino;
-		__jffs2_free_raw_node_ref(this);
-		this = next;
-	}
 }
 
 struct jffs2_node_frag *jffs2_lookup_node_frag(struct rb_root *fragtree, uint32_t offset)
@@ -1060,32 +1058,37 @@ struct jffs2_raw_node_ref *jffs2_link_node_ref(struct jffs2_sb_info *c,
 {
 	struct jffs2_raw_node_ref *ref;
 
-	/* These will be preallocated _very_ shortly. */
-	ref = c->refs;
-	if (!c->refs) {
-		JFFS2_WARNING("Using non-preallocated refs!\n");
-		ref = __jffs2_alloc_raw_node_ref();
-		BUG_ON(!ref);
-		WARN_ON(1);
-	} else {
-		c->refs = ref->next_in_ino;
+	BUG_ON(!jeb->allocated_refs);
+	jeb->allocated_refs--;
+
+	ref = jeb->last_node;
+
+	dbg_noderef("Last node at %p is (%08x,%p)\n", ref, ref->flash_offset,
+		    ref->next_in_ino);
+
+	while (ref->flash_offset != REF_EMPTY_NODE) {
+		if (ref->flash_offset == REF_LINK_NODE)
+			ref = ref->next_in_ino;
+		else
+			ref++;
 	}
 
-	ref->next_phys = NULL;
+	dbg_noderef("New ref is %p (%08x becomes %08x,%p) len 0x%x\n", ref, 
+		    ref->flash_offset, ofs, ref->next_in_ino, len);
+
 	ref->flash_offset = ofs;
 
-	if (!jeb->first_node)
+	if (!jeb->first_node) {
 		jeb->first_node = ref;
-	if (jeb->last_node) {
-		jeb->last_node->next_phys = ref;
-#ifdef TEST_TOTLEN
-		if (ref_offset(jeb->last_node) + jeb->last_node->__totlen != ref_offset(ref)) {
-			printk(KERN_CRIT "Adding new ref %p at (0x%08x-0x%08x) not immediately after previous (0x%08x-0x%08x)\n",
-			       ref, ref_offset(ref), ref_offset(ref)+ref->__totlen,
-			       ref_offset(jeb->last_node), ref_offset(jeb->last_node)+jeb->last_node->__totlen);
-			WARN_ON(1);
-		}
-#endif
+		BUG_ON(ref_offset(ref) != jeb->offset);
+	} else if (unlikely(ref_offset(ref) != jeb->offset + c->sector_size - jeb->free_size)) {
+		uint32_t last_len = ref_totlen(c, jeb, jeb->last_node);
+
+		JFFS2_ERROR("Adding new ref %p at (0x%08x-0x%08x) not immediately after previous (0x%08x-0x%08x)\n",
+			    ref, ref_offset(ref), ref_offset(ref)+len,
+			    ref_offset(jeb->last_node), 
+			    ref_offset(jeb->last_node)+last_len);
+		BUG();
 	}
 	jeb->last_node = ref;
 
@@ -1130,12 +1133,13 @@ int jffs2_scan_dirty_space(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb
 {
 	if (!size)
 		return 0;
-	if (size > c->sector_size - jeb->used_size) {
-		printk(KERN_CRIT "Dirty space 0x%x larger then used_size 0x%x (wasted 0x%x)\n",
-		       size, jeb->used_size, jeb->wasted_size);
+	if (unlikely(size > jeb->free_size)) {
+		printk(KERN_CRIT "Dirty space 0x%x larger then free_size 0x%x (wasted 0x%x)\n",
+		       size, jeb->free_size, jeb->wasted_size);
 		BUG();
 	}
-	if (jeb->last_node && ref_obsolete(jeb->last_node)) {
+	/* REF_EMPTY_NODE is !obsolete, so that works OK */
+	if (ref_obsolete(jeb->last_node)) {
 #ifdef TEST_TOTLEN
 		jeb->last_node->__totlen += size;
 #endif
@@ -1168,7 +1172,7 @@ static inline uint32_t __ref_totlen(struct jffs2_sb_info *c,
 			jeb = &c->blocks[ref->flash_offset / c->sector_size];
 
 		/* Last node in block. Use free_space */
-		if (ref != jeb->last_node) {
+		if (unlikely(ref != jeb->last_node)) {
 			printk(KERN_CRIT "ref %p @0x%08x is not jeb->last_node (%p @0x%08x)\n",
 			       ref, ref_offset(ref), jeb->last_node, jeb->last_node?ref_offset(jeb->last_node):0);
 			BUG();
@@ -1183,17 +1187,13 @@ uint32_t __jffs2_ref_totlen(struct jffs2_sb_info *c, struct jffs2_eraseblock *je
 {
 	uint32_t ret;
 
-#if CONFIG_JFFS2_FS_DEBUG > 0
-	if (jeb && jeb != &c->blocks[ref->flash_offset / c->sector_size]) {
-		printk(KERN_CRIT "ref_totlen called with wrong block -- at 0x%08x instead of 0x%08x; ref 0x%08x\n",
-		       jeb->offset, c->blocks[ref->flash_offset / c->sector_size].offset, ref_offset(ref));
-		BUG();
-	}
-#endif
-
 	ret = __ref_totlen(c, jeb, ref);
+
 #ifdef TEST_TOTLEN
-	if (ret != ref->__totlen) {
+	if (unlikely(ret != ref->__totlen)) {
+		if (!jeb)
+			jeb = &c->blocks[ref->flash_offset / c->sector_size];
+
 		printk(KERN_CRIT "Totlen for ref at %p (0x%08x-0x%08x) miscalculated as 0x%x instead of %x\n",
 		       ref, ref_offset(ref), ref_offset(ref)+ref->__totlen,
 		       ret, ref->__totlen);
@@ -1204,13 +1204,14 @@ uint32_t __jffs2_ref_totlen(struct jffs2_sb_info *c, struct jffs2_eraseblock *je
 			printk(KERN_CRIT "No next ref. jeb->last_node is %p\n", jeb->last_node);
 
 		printk(KERN_CRIT "jeb->wasted_size %x, dirty_size %x, used_size %x, free_size %x\n", jeb->wasted_size, jeb->dirty_size, jeb->used_size, jeb->free_size);
-		ret = ref->__totlen;
-		if (!jeb)
-			jeb = &c->blocks[ref->flash_offset / c->sector_size];
+
 #if defined(JFFS2_DBG_DUMPS) || defined(JFFS2_DBG_PARANOIA_CHECKS)
 		__jffs2_dbg_dump_node_refs_nolock(c, jeb);
 #endif
+
 		WARN_ON(1);
+
+		ret = ref->__totlen;
 	}
 #endif /* TEST_TOTLEN */
 	return ret;