1 files changed, 29 insertions, 33 deletions

diff --git a/fs/jffs2/scan.c b/fs/jffs2/scan.c
index 7fb45bd4915c..2a1c976c7924 100644
--- a/fs/jffs2/scan.c
+++ b/fs/jffs2/scan.c
@@ -1,15 +1,14 @@
 /*
  * JFFS2 -- Journalling Flash File System, Version 2.
  *
- * Copyright (C) 2001-2003 Red Hat, Inc.
+ * Copyright © 2001-2007 Red Hat, Inc.
  *
  * Created by David Woodhouse <dwmw2@infradead.org>
  *
  * For licensing information, see the file 'LICENCE' in this directory.
  *
- * $Id: scan.c,v 1.125 2005/09/30 13:59:13 dedekind Exp $
- *
  */
+
 #include <linux/kernel.h>
 #include <linux/sched.h>
 #include <linux/slab.h>
@@ -636,16 +635,17 @@ scan_more:
 
                 if (*(uint32_t *)(&buf[ofs-buf_ofs]) == 0xffffffff) {
                         uint32_t inbuf_ofs;
-                        uint32_t empty_start;
+                        uint32_t empty_start, scan_end;
 
                         empty_start = ofs;
                         ofs += 4;
+                        scan_end = min_t(uint32_t, EMPTY_SCAN_SIZE(c->sector_size)/8, buf_len);
 
                         D1(printk(KERN_DEBUG "Found empty flash at 0x%08x\n", ofs));
                 more_empty:
                         inbuf_ofs = ofs - buf_ofs;
-                        while (inbuf_ofs < buf_len) {
-                                if (*(uint32_t *)(&buf[inbuf_ofs]) != 0xffffffff) {
+                        while (inbuf_ofs < scan_end) {
+                                if (unlikely(*(uint32_t *)(&buf[inbuf_ofs]) != 0xffffffff)) {
                                         printk(KERN_WARNING "Empty flash at 0x%08x ends at 0x%08x\n",
                                                empty_start, ofs);
                                         if ((err = jffs2_scan_dirty_space(c, jeb, ofs-empty_start)))
@@ -666,7 +666,11 @@ scan_more:
                                 D1(printk(KERN_DEBUG "%d bytes at start of block seems clean... assuming all clean\n", EMPTY_SCAN_SIZE(c->sector_size)));
                                 return BLK_STATE_CLEANMARKER;
                         }
-
+                        if (!buf_size && (scan_end != buf_len)) {/* XIP/point case */
+                                scan_end = buf_len;
+                                goto more_empty;
+                        }
+                        
                         /* See how much more there is to read in this eraseblock... */
                         buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs);
                         if (!buf_len) {
@@ -676,6 +680,8 @@ scan_more:
                                           empty_start));
                                 break;
                         }
+                        /* point never reaches here */
+                        scan_end = buf_len;
                         D1(printk(KERN_DEBUG "Reading another 0x%x at 0x%08x\n", buf_len, ofs));
                         err = jffs2_fill_scan_buf(c, buf, ofs, buf_len);
                         if (err)
@@ -734,18 +740,8 @@ scan_more:
                         ofs += 4;
                         continue;
                 }
-                /* Due to poor choice of crc32 seed, an all-zero node will have a correct CRC */
-                if (!je32_to_cpu(node->hdr_crc) && !je16_to_cpu(node->nodetype) &&
-                    !je16_to_cpu(node->magic) && !je32_to_cpu(node->totlen)) {
-                        noisy_printk(&noise, "jffs2_scan_eraseblock(): All zero node header at 0x%08x.\n", ofs);
-                        if ((err = jffs2_scan_dirty_space(c, jeb, 4)))
-                                return err;
-                        ofs += 4;
-                        continue;
-                }
 
-                if (ofs + je32_to_cpu(node->totlen) >
-                    jeb->offset + c->sector_size) {
+                if (ofs + je32_to_cpu(node->totlen) > jeb->offset + c->sector_size) {
                         /* Eep. Node goes over the end of the erase block. */
                         printk(KERN_WARNING "Node at 0x%08x with length 0x%08x would run over the end of the erase block\n",
                                ofs, je32_to_cpu(node->totlen));
@@ -952,8 +948,7 @@ static int jffs2_scan_inode_node(struct jffs2_sb_info *c, struct jffs2_erasebloc
                                  struct jffs2_raw_inode *ri, uint32_t ofs, struct jffs2_summary *s)
 {
         struct jffs2_inode_cache *ic;
-        uint32_t ino = je32_to_cpu(ri->ino);
-        int err;
+        uint32_t crc, ino = je32_to_cpu(ri->ino);
 
         D1(printk(KERN_DEBUG "jffs2_scan_inode_node(): Node at 0x%08x\n", ofs));
 
@@ -966,21 +961,22 @@ static int jffs2_scan_inode_node(struct jffs2_sb_info *c, struct jffs2_erasebloc
            Which means that the _full_ amount of time to get to proper write mode with GC
            operational may actually be _longer_ than before. Sucks to be me. */
 
+        /* Check the node CRC in any case. */
+        crc = crc32(0, ri, sizeof(*ri)-8);
+        if (crc != je32_to_cpu(ri->node_crc)) {
+                printk(KERN_NOTICE "jffs2_scan_inode_node(): CRC failed on "
+                       "node at 0x%08x: Read 0x%08x, calculated 0x%08x\n",
+                       ofs, je32_to_cpu(ri->node_crc), crc);
+                /*
+                 * We believe totlen because the CRC on the node
+                 * _header_ was OK, just the node itself failed.
+                 */
+                return jffs2_scan_dirty_space(c, jeb,
+                                              PAD(je32_to_cpu(ri->totlen)));
+        }
+
         ic = jffs2_get_ino_cache(c, ino);
         if (!ic) {
-                /* Inocache get failed. Either we read a bogus ino# or it's just genuinely the
-                   first node we found for this inode. Do a CRC check to protect against the former
-                   case */
-                uint32_t crc = crc32(0, ri, sizeof(*ri)-8);
-
-                if (crc != je32_to_cpu(ri->node_crc)) {
-                        printk(KERN_NOTICE "jffs2_scan_inode_node(): CRC failed on node at 0x%08x: Read 0x%08x, calculated 0x%08x\n",
-                               ofs, je32_to_cpu(ri->node_crc), crc);
-                        /* We believe totlen because the CRC on the node _header_ was OK, just the node itself failed. */
-                        if ((err = jffs2_scan_dirty_space(c, jeb, PAD(je32_to_cpu(ri->totlen)))))
-                                return err;
-                        return 0;
-                }
                 ic = jffs2_scan_make_ino_cache(c, ino);
                 if (!ic)
                         return -ENOMEM;