[JFFS2] Finally eliminate __totlen field from struct jffs2_raw_node_ref

Well, almost. We'll actually keep a 'TEST_TOTLEN' macro set for now, and keep
doing some paranoia checks to make sure it's all working correctly. But if
TEST_TOTLEN is unset, the size of struct jffs2_raw_node_ref drops from 16
bytes to 12 on 32-bit machines. That's a saving of about half a megabyte of
memory on the OLPC prototype board, with 125K or so nodes in its 512MiB of
flash.

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

1 files changed, 7 insertions, 51 deletions

diff --git a/fs/jffs2/nodelist.h b/fs/jffs2/nodelist.h
index 94ef88787347..80d1fda2212b 100644
--- a/fs/jffs2/nodelist.h
+++ b/fs/jffs2/nodelist.h
@@ -82,7 +82,10 @@ struct jffs2_raw_node_ref
                 word so you know when you've got there :) */
         struct jffs2_raw_node_ref *next_phys;
         uint32_t flash_offset;
+#define TEST_TOTLEN
+#ifdef TEST_TOTLEN
         uint32_t __totlen; /* This may die; use ref_totlen(c, jeb, ) below */
+#endif
 };
 
         /* flash_offset & 3 always has to be zero, because nodes are
@@ -221,57 +224,7 @@ static inline int jffs2_blocks_use_vmalloc(struct jffs2_sb_info *c)
         return ((c->flash_size / c->sector_size) * sizeof (struct jffs2_eraseblock)) > (128 * 1024);
 }
 
-/* Calculate totlen from surrounding nodes or eraseblock */
-static inline uint32_t __ref_totlen(struct jffs2_sb_info *c,
-                                    struct jffs2_eraseblock *jeb,
-                                    struct jffs2_raw_node_ref *ref)
-{
-        uint32_t ref_end;
-
-        if (ref->next_phys)
-                ref_end = ref_offset(ref->next_phys);
-        else {
-                if (!jeb)
-                        jeb = &c->blocks[ref->flash_offset / c->sector_size];
-
-                /* Last node in block. Use free_space */
-                BUG_ON(ref != jeb->last_node);
-                ref_end = jeb->offset + c->sector_size - jeb->free_size;
-        }
-        return ref_end - ref_offset(ref);
-}
-
-static inline uint32_t ref_totlen(struct jffs2_sb_info *c,
-                                  struct jffs2_eraseblock *jeb,
-                                  struct jffs2_raw_node_ref *ref)
-{
-        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
-
-#if 1
-        ret = ref->__totlen;
-#else
-        /* This doesn't actually work yet */
-        ret = __ref_totlen(c, jeb, ref);
-        if (ret != ref->__totlen) {
-                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);
-                if (!jeb)
-                        jeb = &c->blocks[ref->flash_offset / c->sector_size];
-                jffs2_dbg_dump_node_refs_nolock(c, jeb);
-                BUG();
-        }
-#endif
-        return ret;
-}
+#define ref_totlen(a, b, c) __jffs2_ref_totlen((a), (b), (c))
 
 #define ALLOC_NORMAL    0       /* Normal allocation */
 #define ALLOC_DELETION  1       /* Deletion node. Best to allow it */
@@ -355,6 +308,9 @@ void jffs2_truncate_fragtree (struct jffs2_sb_info *c, struct rb_root *list, uin
 int jffs2_add_older_frag_to_fragtree(struct jffs2_sb_info *c, struct jffs2_inode_info *f, struct jffs2_tmp_dnode_info *tn);
 void jffs2_link_node_ref(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
                          struct jffs2_raw_node_ref *ref, uint32_t len);
+extern uint32_t __jffs2_ref_totlen(struct jffs2_sb_info *c,
+                                   struct jffs2_eraseblock *jeb,
+                                   struct jffs2_raw_node_ref *ref);
 
 /* nodemgmt.c */
 int jffs2_thread_should_wake(struct jffs2_sb_info *c);