- patches.apparmor/remove_suid_new_case_in_2.6.22.diff: Merge fix.
[linux-flexiantxendom0-3.2.10.git] / fs / jffs2 / scan.c
index 7fb45bd..2a1c976 100644 (file)
@@ -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;