Linux-2.6.12-rc2v2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 916 insertions, 0 deletions

diff --git a/fs/jffs2/scan.c b/fs/jffs2/scan.c
new file mode 100644
index 000000000000..ded53584a897
--- /dev/null
+++ b/fs/jffs2/scan.c
@@ -0,0 +1,916 @@
+/*
+ * JFFS2 -- Journalling Flash File System, Version 2.
+ *
+ * Copyright (C) 2001-2003 Red Hat, Inc.
+ *
+ * Created by David Woodhouse <dwmw2@infradead.org>
+ *
+ * For licensing information, see the file 'LICENCE' in this directory.
+ *
+ * $Id: scan.c,v 1.115 2004/11/17 12:59:08 dedekind Exp $
+ *
+ */
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/mtd/mtd.h>
+#include <linux/pagemap.h>
+#include <linux/crc32.h>
+#include <linux/compiler.h>
+#include "nodelist.h"
+
+#define EMPTY_SCAN_SIZE 1024
+
+#define DIRTY_SPACE(x) do { typeof(x) _x = (x); \
+		c->free_size -= _x; c->dirty_size += _x; \
+		jeb->free_size -= _x ; jeb->dirty_size += _x; \
+		}while(0)
+#define USED_SPACE(x) do { typeof(x) _x = (x); \
+		c->free_size -= _x; c->used_size += _x; \
+		jeb->free_size -= _x ; jeb->used_size += _x; \
+		}while(0)
+#define UNCHECKED_SPACE(x) do { typeof(x) _x = (x); \
+		c->free_size -= _x; c->unchecked_size += _x; \
+		jeb->free_size -= _x ; jeb->unchecked_size += _x; \
+		}while(0)
+
+#define noisy_printk(noise, args...) do { \
+	if (*(noise)) { \
+		printk(KERN_NOTICE args); \
+		 (*(noise))--; \
+		 if (!(*(noise))) { \
+			 printk(KERN_NOTICE "Further such events for this erase block will not be printed\n"); \
+		 } \
+	} \
+} while(0)
+
+static uint32_t pseudo_random;
+
+static int jffs2_scan_eraseblock (struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
+				  unsigned char *buf, uint32_t buf_size);
+
+/* These helper functions _must_ increase ofs and also do the dirty/used space accounting. 
+ * Returning an error will abort the mount - bad checksums etc. should just mark the space
+ * as dirty.
+ */
+static int jffs2_scan_inode_node(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, 
+				 struct jffs2_raw_inode *ri, uint32_t ofs);
+static int jffs2_scan_dirent_node(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
+				 struct jffs2_raw_dirent *rd, uint32_t ofs);
+
+#define BLK_STATE_ALLFF		0
+#define BLK_STATE_CLEAN		1
+#define BLK_STATE_PARTDIRTY	2
+#define BLK_STATE_CLEANMARKER	3
+#define BLK_STATE_ALLDIRTY	4
+#define BLK_STATE_BADBLOCK	5
+
+static inline int min_free(struct jffs2_sb_info *c)
+{
+	uint32_t min = 2 * sizeof(struct jffs2_raw_inode);
+#if defined CONFIG_JFFS2_FS_NAND || defined CONFIG_JFFS2_FS_NOR_ECC
+	if (!jffs2_can_mark_obsolete(c) && min < c->wbuf_pagesize)
+		return c->wbuf_pagesize;
+#endif
+	return min;
+
+}
+int jffs2_scan_medium(struct jffs2_sb_info *c)
+{
+	int i, ret;
+	uint32_t empty_blocks = 0, bad_blocks = 0;
+	unsigned char *flashbuf = NULL;
+	uint32_t buf_size = 0;
+#ifndef __ECOS
+	size_t pointlen;
+
+	if (c->mtd->point) {
+		ret = c->mtd->point (c->mtd, 0, c->mtd->size, &pointlen, &flashbuf);
+		if (!ret && pointlen < c->mtd->size) {
+			/* Don't muck about if it won't let us point to the whole flash */
+			D1(printk(KERN_DEBUG "MTD point returned len too short: 0x%zx\n", pointlen));
+			c->mtd->unpoint(c->mtd, flashbuf, 0, c->mtd->size);
+			flashbuf = NULL;
+		}
+		if (ret)
+			D1(printk(KERN_DEBUG "MTD point failed %d\n", ret));
+	}
+#endif
+	if (!flashbuf) {
+		/* For NAND it's quicker to read a whole eraseblock at a time,
+		   apparently */
+		if (jffs2_cleanmarker_oob(c))
+			buf_size = c->sector_size;
+		else
+			buf_size = PAGE_SIZE;
+
+		/* Respect kmalloc limitations */
+		if (buf_size > 128*1024)
+			buf_size = 128*1024;
+
+		D1(printk(KERN_DEBUG "Allocating readbuf of %d bytes\n", buf_size));
+		flashbuf = kmalloc(buf_size, GFP_KERNEL);
+		if (!flashbuf)
+			return -ENOMEM;
+	}
+
+	for (i=0; i<c->nr_blocks; i++) {
+		struct jffs2_eraseblock *jeb = &c->blocks[i];
+
+		ret = jffs2_scan_eraseblock(c, jeb, buf_size?flashbuf:(flashbuf+jeb->offset), buf_size);
+
+		if (ret < 0)
+			goto out;
+
+		ACCT_PARANOIA_CHECK(jeb);
+
+		/* Now decide which list to put it on */
+		switch(ret) {
+		case BLK_STATE_ALLFF:
+			/* 
+			 * Empty block.   Since we can't be sure it 
+			 * was entirely erased, we just queue it for erase
+			 * again.  It will be marked as such when the erase
+			 * is complete.  Meanwhile we still count it as empty
+			 * for later checks.
+			 */
+			empty_blocks++;
+			list_add(&jeb->list, &c->erase_pending_list);
+			c->nr_erasing_blocks++;
+			break;
+
+		case BLK_STATE_CLEANMARKER:
+			/* Only a CLEANMARKER node is valid */
+			if (!jeb->dirty_size) {
+				/* It's actually free */
+				list_add(&jeb->list, &c->free_list);
+				c->nr_free_blocks++;
+			} else {
+				/* Dirt */
+				D1(printk(KERN_DEBUG "Adding all-dirty block at 0x%08x to erase_pending_list\n", jeb->offset));
+				list_add(&jeb->list, &c->erase_pending_list);
+				c->nr_erasing_blocks++;
+			}
+			break;
+
+		case BLK_STATE_CLEAN:
+                        /* Full (or almost full) of clean data. Clean list */
+                        list_add(&jeb->list, &c->clean_list);
+			break;
+
+		case BLK_STATE_PARTDIRTY:
+                        /* Some data, but not full. Dirty list. */
+                        /* We want to remember the block with most free space
+                           and stick it in the 'nextblock' position to start writing to it. */
+                        if (jeb->free_size > min_free(c) && 
+			    (!c->nextblock || c->nextblock->free_size < jeb->free_size)) {
+                                /* Better candidate for the next writes to go to */
+                                if (c->nextblock) {
+					c->nextblock->dirty_size += c->nextblock->free_size + c->nextblock->wasted_size;
+					c->dirty_size += c->nextblock->free_size + c->nextblock->wasted_size;
+					c->free_size -= c->nextblock->free_size;
+					c->wasted_size -= c->nextblock->wasted_size;
+					c->nextblock->free_size = c->nextblock->wasted_size = 0;
+					if (VERYDIRTY(c, c->nextblock->dirty_size)) {
+						list_add(&c->nextblock->list, &c->very_dirty_list);
+					} else {
+						list_add(&c->nextblock->list, &c->dirty_list);
+					}
+				}
+                                c->nextblock = jeb;
+                        } else {
+				jeb->dirty_size += jeb->free_size + jeb->wasted_size;
+				c->dirty_size += jeb->free_size + jeb->wasted_size;
+				c->free_size -= jeb->free_size;
+				c->wasted_size -= jeb->wasted_size;
+				jeb->free_size = jeb->wasted_size = 0;
+				if (VERYDIRTY(c, jeb->dirty_size)) {
+					list_add(&jeb->list, &c->very_dirty_list);
+				} else {
+					list_add(&jeb->list, &c->dirty_list);
+				}
+                        }
+			break;
+
+		case BLK_STATE_ALLDIRTY:
+			/* Nothing valid - not even a clean marker. Needs erasing. */
+                        /* For now we just put it on the erasing list. We'll start the erases later */
+			D1(printk(KERN_NOTICE "JFFS2: Erase block at 0x%08x is not formatted. It will be erased\n", jeb->offset));
+                        list_add(&jeb->list, &c->erase_pending_list);
+			c->nr_erasing_blocks++;
+			break;
+			
+		case BLK_STATE_BADBLOCK:
+			D1(printk(KERN_NOTICE "JFFS2: Block at 0x%08x is bad\n", jeb->offset));
+                        list_add(&jeb->list, &c->bad_list);
+			c->bad_size += c->sector_size;
+			c->free_size -= c->sector_size;
+			bad_blocks++;
+			break;
+		default:
+			printk(KERN_WARNING "jffs2_scan_medium(): unknown block state\n");
+			BUG();	
+		}
+	}
+	
+	/* Nextblock dirty is always seen as wasted, because we cannot recycle it now */
+	if (c->nextblock && (c->nextblock->dirty_size)) {
+		c->nextblock->wasted_size += c->nextblock->dirty_size;
+		c->wasted_size += c->nextblock->dirty_size;
+		c->dirty_size -= c->nextblock->dirty_size;
+		c->nextblock->dirty_size = 0;
+	}
+#if defined CONFIG_JFFS2_FS_NAND || defined CONFIG_JFFS2_FS_NOR_ECC
+	if (!jffs2_can_mark_obsolete(c) && c->nextblock && (c->nextblock->free_size & (c->wbuf_pagesize-1))) {
+		/* If we're going to start writing into a block which already 
+		   contains data, and the end of the data isn't page-aligned,
+		   skip a little and align it. */
+
+		uint32_t skip = c->nextblock->free_size & (c->wbuf_pagesize-1);
+
+		D1(printk(KERN_DEBUG "jffs2_scan_medium(): Skipping %d bytes in nextblock to ensure page alignment\n",
+			  skip));
+		c->nextblock->wasted_size += skip;
+		c->wasted_size += skip;
+
+		c->nextblock->free_size -= skip;
+		c->free_size -= skip;
+	}
+#endif
+	if (c->nr_erasing_blocks) {
+		if ( !c->used_size && ((c->nr_free_blocks+empty_blocks+bad_blocks)!= c->nr_blocks || bad_blocks == c->nr_blocks) ) { 
+			printk(KERN_NOTICE "Cowardly refusing to erase blocks on filesystem with no valid JFFS2 nodes\n");
+			printk(KERN_NOTICE "empty_blocks %d, bad_blocks %d, c->nr_blocks %d\n",empty_blocks,bad_blocks,c->nr_blocks);
+			ret = -EIO;
+			goto out;
+		}
+		jffs2_erase_pending_trigger(c);
+	}
+	ret = 0;
+ out:
+	if (buf_size)
+		kfree(flashbuf);
+#ifndef __ECOS
+	else 
+		c->mtd->unpoint(c->mtd, flashbuf, 0, c->mtd->size);
+#endif
+	return ret;
+}
+
+static int jffs2_fill_scan_buf (struct jffs2_sb_info *c, unsigned char *buf,
+				uint32_t ofs, uint32_t len)
+{
+	int ret;
+	size_t retlen;
+
+	ret = jffs2_flash_read(c, ofs, len, &retlen, buf);
+	if (ret) {
+		D1(printk(KERN_WARNING "mtd->read(0x%x bytes from 0x%x) returned %d\n", len, ofs, ret));
+		return ret;
+	}
+	if (retlen < len) {
+		D1(printk(KERN_WARNING "Read at 0x%x gave only 0x%zx bytes\n", ofs, retlen));
+		return -EIO;
+	}
+	D2(printk(KERN_DEBUG "Read 0x%x bytes from 0x%08x into buf\n", len, ofs));
+	D2(printk(KERN_DEBUG "000: %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x\n",
+		  buf[0], buf[1], buf[2], buf[3], buf[4], buf[5], buf[6], buf[7], buf[8], buf[9], buf[10], buf[11], buf[12], buf[13], buf[14], buf[15]));
+	return 0;
+}
+
+static int jffs2_scan_eraseblock (struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
+				  unsigned char *buf, uint32_t buf_size) {
+	struct jffs2_unknown_node *node;
+	struct jffs2_unknown_node crcnode;
+	uint32_t ofs, prevofs;
+	uint32_t hdr_crc, buf_ofs, buf_len;
+	int err;
+	int noise = 0;
+#ifdef CONFIG_JFFS2_FS_NAND
+	int cleanmarkerfound = 0;
+#endif
+
+	ofs = jeb->offset;
+	prevofs = jeb->offset - 1;
+
+	D1(printk(KERN_DEBUG "jffs2_scan_eraseblock(): Scanning block at 0x%x\n", ofs));
+
+#ifdef CONFIG_JFFS2_FS_NAND
+	if (jffs2_cleanmarker_oob(c)) {
+		int ret = jffs2_check_nand_cleanmarker(c, jeb);
+		D2(printk(KERN_NOTICE "jffs_check_nand_cleanmarker returned %d\n",ret));
+		/* Even if it's not found, we still scan to see
+		   if the block is empty. We use this information
+		   to decide whether to erase it or not. */
+		switch (ret) {
+		case 0:		cleanmarkerfound = 1; break;
+		case 1: 	break;
+		case 2: 	return BLK_STATE_BADBLOCK;
+		case 3:		return BLK_STATE_ALLDIRTY; /* Block has failed to erase min. once */
+		default: 	return ret;
+		}
+	}
+#endif
+	buf_ofs = jeb->offset;
+
+	if (!buf_size) {
+		buf_len = c->sector_size;
+	} else {
+		buf_len = EMPTY_SCAN_SIZE;
+		err = jffs2_fill_scan_buf(c, buf, buf_ofs, buf_len);
+		if (err)
+			return err;
+	}
+	
+	/* We temporarily use 'ofs' as a pointer into the buffer/jeb */
+	ofs = 0;
+
+	/* Scan only 4KiB of 0xFF before declaring it's empty */
+	while(ofs < EMPTY_SCAN_SIZE && *(uint32_t *)(&buf[ofs]) == 0xFFFFFFFF)
+		ofs += 4;
+
+	if (ofs == EMPTY_SCAN_SIZE) {
+#ifdef CONFIG_JFFS2_FS_NAND
+		if (jffs2_cleanmarker_oob(c)) {
+			/* scan oob, take care of cleanmarker */
+			int ret = jffs2_check_oob_empty(c, jeb, cleanmarkerfound);
+			D2(printk(KERN_NOTICE "jffs2_check_oob_empty returned %d\n",ret));
+			switch (ret) {
+			case 0:		return cleanmarkerfound ? BLK_STATE_CLEANMARKER : BLK_STATE_ALLFF;
+			case 1: 	return BLK_STATE_ALLDIRTY;
+			default: 	return ret;
+			}
+		}
+#endif
+		D1(printk(KERN_DEBUG "Block at 0x%08x is empty (erased)\n", jeb->offset));
+		return BLK_STATE_ALLFF;	/* OK to erase if all blocks are like this */
+	}
+	if (ofs) {
+		D1(printk(KERN_DEBUG "Free space at %08x ends at %08x\n", jeb->offset,
+			  jeb->offset + ofs));
+		DIRTY_SPACE(ofs);
+	}
+
+	/* Now ofs is a complete physical flash offset as it always was... */
+	ofs += jeb->offset;
+
+	noise = 10;
+
+scan_more:	
+	while(ofs < jeb->offset + c->sector_size) {
+
+		D1(ACCT_PARANOIA_CHECK(jeb));
+
+		cond_resched();
+
+		if (ofs & 3) {
+			printk(KERN_WARNING "Eep. ofs 0x%08x not word-aligned!\n", ofs);
+			ofs = PAD(ofs);
+			continue;
+		}
+		if (ofs == prevofs) {
+			printk(KERN_WARNING "ofs 0x%08x has already been seen. Skipping\n", ofs);
+			DIRTY_SPACE(4);
+			ofs += 4;
+			continue;
+		}
+		prevofs = ofs;
+
+		if (jeb->offset + c->sector_size < ofs + sizeof(*node)) {
+			D1(printk(KERN_DEBUG "Fewer than %zd bytes left to end of block. (%x+%x<%x+%zx) Not reading\n", sizeof(struct jffs2_unknown_node),
+				  jeb->offset, c->sector_size, ofs, sizeof(*node)));
+			DIRTY_SPACE((jeb->offset + c->sector_size)-ofs);
+			break;
+		}
+
+		if (buf_ofs + buf_len < ofs + sizeof(*node)) {
+			buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs);
+			D1(printk(KERN_DEBUG "Fewer than %zd bytes (node header) left to end of buf. Reading 0x%x at 0x%08x\n",
+				  sizeof(struct jffs2_unknown_node), buf_len, ofs));
+			err = jffs2_fill_scan_buf(c, buf, ofs, buf_len);
+			if (err)
+				return err;
+			buf_ofs = ofs;
+		}
+
+		node = (struct jffs2_unknown_node *)&buf[ofs-buf_ofs];
+
+		if (*(uint32_t *)(&buf[ofs-buf_ofs]) == 0xffffffff) {
+			uint32_t inbuf_ofs;
+			uint32_t empty_start;
+
+			empty_start = ofs;
+			ofs += 4;
+
+			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) {
+					printk(KERN_WARNING "Empty flash at 0x%08x ends at 0x%08x\n",
+					       empty_start, ofs);
+					DIRTY_SPACE(ofs-empty_start);
+					goto scan_more;
+				}
+
+				inbuf_ofs+=4;
+				ofs += 4;
+			}
+			/* Ran off end. */
+			D1(printk(KERN_DEBUG "Empty flash to end of buffer at 0x%08x\n", ofs));
+
+			/* If we're only checking the beginning of a block with a cleanmarker,
+			   bail now */
+			if (buf_ofs == jeb->offset && jeb->used_size == PAD(c->cleanmarker_size) && 
+			    c->cleanmarker_size && !jeb->dirty_size && !jeb->first_node->next_in_ino) {
+				D1(printk(KERN_DEBUG "%d bytes at start of block seems clean... assuming all clean\n", EMPTY_SCAN_SIZE));
+				return BLK_STATE_CLEANMARKER;
+			}
+
+			/* 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) {
+				/* No more to read. Break out of main loop without marking 
+				   this range of empty space as dirty (because it's not) */
+				D1(printk(KERN_DEBUG "Empty flash at %08x runs to end of block. Treating as free_space\n",
+					  empty_start));
+				break;
+			}
+			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)
+				return err;
+			buf_ofs = ofs;
+			goto more_empty;
+		}
+
+		if (ofs == jeb->offset && je16_to_cpu(node->magic) == KSAMTIB_CIGAM_2SFFJ) {
+			printk(KERN_WARNING "Magic bitmask is backwards at offset 0x%08x. Wrong endian filesystem?\n", ofs);
+			DIRTY_SPACE(4);
+			ofs += 4;
+			continue;
+		}
+		if (je16_to_cpu(node->magic) == JFFS2_DIRTY_BITMASK) {
+			D1(printk(KERN_DEBUG "Dirty bitmask at 0x%08x\n", ofs));
+			DIRTY_SPACE(4);
+			ofs += 4;
+			continue;
+		}
+		if (je16_to_cpu(node->magic) == JFFS2_OLD_MAGIC_BITMASK) {
+			printk(KERN_WARNING "Old JFFS2 bitmask found at 0x%08x\n", ofs);
+			printk(KERN_WARNING "You cannot use older JFFS2 filesystems with newer kernels\n");
+			DIRTY_SPACE(4);
+			ofs += 4;
+			continue;
+		}
+		if (je16_to_cpu(node->magic) != JFFS2_MAGIC_BITMASK) {
+			/* OK. We're out of possibilities. Whinge and move on */
+			noisy_printk(&noise, "jffs2_scan_eraseblock(): Magic bitmask 0x%04x not found at 0x%08x: 0x%04x instead\n", 
+				     JFFS2_MAGIC_BITMASK, ofs, 
+				     je16_to_cpu(node->magic));
+			DIRTY_SPACE(4);
+			ofs += 4;
+			continue;
+		}
+		/* We seem to have a node of sorts. Check the CRC */
+		crcnode.magic = node->magic;
+		crcnode.nodetype = cpu_to_je16( je16_to_cpu(node->nodetype) | JFFS2_NODE_ACCURATE);
+		crcnode.totlen = node->totlen;
+		hdr_crc = crc32(0, &crcnode, sizeof(crcnode)-4);
+
+		if (hdr_crc != je32_to_cpu(node->hdr_crc)) {
+			noisy_printk(&noise, "jffs2_scan_eraseblock(): Node at 0x%08x {0x%04x, 0x%04x, 0x%08x) has invalid CRC 0x%08x (calculated 0x%08x)\n",
+				     ofs, je16_to_cpu(node->magic),
+				     je16_to_cpu(node->nodetype), 
+				     je32_to_cpu(node->totlen),
+				     je32_to_cpu(node->hdr_crc),
+				     hdr_crc);
+			DIRTY_SPACE(4);
+			ofs += 4;
+			continue;
+		}
+
+		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));
+			printk(KERN_WARNING "Perhaps the file system was created with the wrong erase size?\n");
+			DIRTY_SPACE(4);
+			ofs += 4;
+			continue;
+		}
+
+		if (!(je16_to_cpu(node->nodetype) & JFFS2_NODE_ACCURATE)) {
+			/* Wheee. This is an obsoleted node */
+			D2(printk(KERN_DEBUG "Node at 0x%08x is obsolete. Skipping\n", ofs));
+			DIRTY_SPACE(PAD(je32_to_cpu(node->totlen)));
+			ofs += PAD(je32_to_cpu(node->totlen));
+			continue;
+		}
+
+		switch(je16_to_cpu(node->nodetype)) {
+		case JFFS2_NODETYPE_INODE:
+			if (buf_ofs + buf_len < ofs + sizeof(struct jffs2_raw_inode)) {
+				buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs);
+				D1(printk(KERN_DEBUG "Fewer than %zd bytes (inode node) left to end of buf. Reading 0x%x at 0x%08x\n",
+					  sizeof(struct jffs2_raw_inode), buf_len, ofs));
+				err = jffs2_fill_scan_buf(c, buf, ofs, buf_len);
+				if (err)
+					return err;
+				buf_ofs = ofs;
+				node = (void *)buf;
+			}
+			err = jffs2_scan_inode_node(c, jeb, (void *)node, ofs);
+			if (err) return err;
+			ofs += PAD(je32_to_cpu(node->totlen));
+			break;
+			
+		case JFFS2_NODETYPE_DIRENT:
+			if (buf_ofs + buf_len < ofs + je32_to_cpu(node->totlen)) {
+				buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs);
+				D1(printk(KERN_DEBUG "Fewer than %d bytes (dirent node) left to end of buf. Reading 0x%x at 0x%08x\n",
+					  je32_to_cpu(node->totlen), buf_len, ofs));
+				err = jffs2_fill_scan_buf(c, buf, ofs, buf_len);
+				if (err)
+					return err;
+				buf_ofs = ofs;
+				node = (void *)buf;
+			}
+			err = jffs2_scan_dirent_node(c, jeb, (void *)node, ofs);
+			if (err) return err;
+			ofs += PAD(je32_to_cpu(node->totlen));
+			break;
+
+		case JFFS2_NODETYPE_CLEANMARKER:
+			D1(printk(KERN_DEBUG "CLEANMARKER node found at 0x%08x\n", ofs));
+			if (je32_to_cpu(node->totlen) != c->cleanmarker_size) {
+				printk(KERN_NOTICE "CLEANMARKER node found at 0x%08x has totlen 0x%x != normal 0x%x\n", 
+				       ofs, je32_to_cpu(node->totlen), c->cleanmarker_size);
+				DIRTY_SPACE(PAD(sizeof(struct jffs2_unknown_node)));
+				ofs += PAD(sizeof(struct jffs2_unknown_node));
+			} else if (jeb->first_node) {
+				printk(KERN_NOTICE "CLEANMARKER node found at 0x%08x, not first node in block (0x%08x)\n", ofs, jeb->offset);
+				DIRTY_SPACE(PAD(sizeof(struct jffs2_unknown_node)));
+				ofs += PAD(sizeof(struct jffs2_unknown_node));
+			} else {
+				struct jffs2_raw_node_ref *marker_ref = jffs2_alloc_raw_node_ref();
+				if (!marker_ref) {
+					printk(KERN_NOTICE "Failed to allocate node ref for clean marker\n");
+					return -ENOMEM;
+				}
+				marker_ref->next_in_ino = NULL;
+				marker_ref->next_phys = NULL;
+				marker_ref->flash_offset = ofs | REF_NORMAL;
+				marker_ref->__totlen = c->cleanmarker_size;
+				jeb->first_node = jeb->last_node = marker_ref;
+			     
+				USED_SPACE(PAD(c->cleanmarker_size));
+				ofs += PAD(c->cleanmarker_size);
+			}
+			break;
+
+		case JFFS2_NODETYPE_PADDING:
+			DIRTY_SPACE(PAD(je32_to_cpu(node->totlen)));
+			ofs += PAD(je32_to_cpu(node->totlen));
+			break;
+
+		default:
+			switch (je16_to_cpu(node->nodetype) & JFFS2_COMPAT_MASK) {
+			case JFFS2_FEATURE_ROCOMPAT:
+				printk(KERN_NOTICE "Read-only compatible feature node (0x%04x) found at offset 0x%08x\n", je16_to_cpu(node->nodetype), ofs);
+			        c->flags |= JFFS2_SB_FLAG_RO;
+				if (!(jffs2_is_readonly(c)))
+					return -EROFS;
+				DIRTY_SPACE(PAD(je32_to_cpu(node->totlen)));
+				ofs += PAD(je32_to_cpu(node->totlen));
+				break;
+
+			case JFFS2_FEATURE_INCOMPAT:
+				printk(KERN_NOTICE "Incompatible feature node (0x%04x) found at offset 0x%08x\n", je16_to_cpu(node->nodetype), ofs);
+				return -EINVAL;
+
+			case JFFS2_FEATURE_RWCOMPAT_DELETE:
+				D1(printk(KERN_NOTICE "Unknown but compatible feature node (0x%04x) found at offset 0x%08x\n", je16_to_cpu(node->nodetype), ofs));
+				DIRTY_SPACE(PAD(je32_to_cpu(node->totlen)));
+				ofs += PAD(je32_to_cpu(node->totlen));
+				break;
+
+			case JFFS2_FEATURE_RWCOMPAT_COPY:
+				D1(printk(KERN_NOTICE "Unknown but compatible feature node (0x%04x) found at offset 0x%08x\n", je16_to_cpu(node->nodetype), ofs));
+				USED_SPACE(PAD(je32_to_cpu(node->totlen)));
+				ofs += PAD(je32_to_cpu(node->totlen));
+				break;
+			}
+		}
+	}
+
+
+	D1(printk(KERN_DEBUG "Block at 0x%08x: free 0x%08x, dirty 0x%08x, unchecked 0x%08x, used 0x%08x\n", jeb->offset, 
+		  jeb->free_size, jeb->dirty_size, jeb->unchecked_size, jeb->used_size));
+
+	/* mark_node_obsolete can add to wasted !! */
+	if (jeb->wasted_size) {
+		jeb->dirty_size += jeb->wasted_size;
+		c->dirty_size += jeb->wasted_size;
+		c->wasted_size -= jeb->wasted_size;
+		jeb->wasted_size = 0;
+	}
+
+	if ((jeb->used_size + jeb->unchecked_size) == PAD(c->cleanmarker_size) && !jeb->dirty_size 
+		&& (!jeb->first_node || !jeb->first_node->next_in_ino) )
+		return BLK_STATE_CLEANMARKER;
+		
+	/* move blocks with max 4 byte dirty space to cleanlist */	
+	else if (!ISDIRTY(c->sector_size - (jeb->used_size + jeb->unchecked_size))) {
+		c->dirty_size -= jeb->dirty_size;
+		c->wasted_size += jeb->dirty_size; 
+		jeb->wasted_size += jeb->dirty_size;
+		jeb->dirty_size = 0;
+		return BLK_STATE_CLEAN;
+	} else if (jeb->used_size || jeb->unchecked_size)
+		return BLK_STATE_PARTDIRTY;
+	else
+		return BLK_STATE_ALLDIRTY;
+}
+
+static struct jffs2_inode_cache *jffs2_scan_make_ino_cache(struct jffs2_sb_info *c, uint32_t ino)
+{
+	struct jffs2_inode_cache *ic;
+
+	ic = jffs2_get_ino_cache(c, ino);
+	if (ic)
+		return ic;
+
+	if (ino > c->highest_ino)
+		c->highest_ino = ino;
+
+	ic = jffs2_alloc_inode_cache();
+	if (!ic) {
+		printk(KERN_NOTICE "jffs2_scan_make_inode_cache(): allocation of inode cache failed\n");
+		return NULL;
+	}
+	memset(ic, 0, sizeof(*ic));
+
+	ic->ino = ino;
+	ic->nodes = (void *)ic;
+	jffs2_add_ino_cache(c, ic);
+	if (ino == 1)
+		ic->nlink = 1;
+	return ic;
+}
+
+static int jffs2_scan_inode_node(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, 
+				 struct jffs2_raw_inode *ri, uint32_t ofs)
+{
+	struct jffs2_raw_node_ref *raw;
+	struct jffs2_inode_cache *ic;
+	uint32_t ino = je32_to_cpu(ri->ino);
+
+	D1(printk(KERN_DEBUG "jffs2_scan_inode_node(): Node at 0x%08x\n", ofs));
+
+	/* We do very little here now. Just check the ino# to which we should attribute
+	   this node; we can do all the CRC checking etc. later. There's a tradeoff here -- 
+	   we used to scan the flash once only, reading everything we want from it into
+	   memory, then building all our in-core data structures and freeing the extra
+	   information. Now we allow the first part of the mount to complete a lot quicker,
+	   but we have to go _back_ to the flash in order to finish the CRC checking, etc. 
+	   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. */
+
+	raw = jffs2_alloc_raw_node_ref();
+	if (!raw) {
+		printk(KERN_NOTICE "jffs2_scan_inode_node(): allocation of node reference failed\n");
+		return -ENOMEM;
+	}
+
+	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. */
+			DIRTY_SPACE(PAD(je32_to_cpu(ri->totlen)));
+			jffs2_free_raw_node_ref(raw);
+			return 0;
+		}
+		ic = jffs2_scan_make_ino_cache(c, ino);
+		if (!ic) {
+			jffs2_free_raw_node_ref(raw);
+			return -ENOMEM;
+		}
+	}
+
+	/* Wheee. It worked */
+
+	raw->flash_offset = ofs | REF_UNCHECKED;
+	raw->__totlen = PAD(je32_to_cpu(ri->totlen));
+	raw->next_phys = NULL;
+	raw->next_in_ino = ic->nodes;
+
+	ic->nodes = raw;
+	if (!jeb->first_node)
+		jeb->first_node = raw;
+	if (jeb->last_node)
+		jeb->last_node->next_phys = raw;
+	jeb->last_node = raw;
+
+	D1(printk(KERN_DEBUG "Node is ino #%u, version %d. Range 0x%x-0x%x\n", 
+		  je32_to_cpu(ri->ino), je32_to_cpu(ri->version),
+		  je32_to_cpu(ri->offset),
+		  je32_to_cpu(ri->offset)+je32_to_cpu(ri->dsize)));
+
+	pseudo_random += je32_to_cpu(ri->version);
+
+	UNCHECKED_SPACE(PAD(je32_to_cpu(ri->totlen)));
+	return 0;
+}
+
+static int jffs2_scan_dirent_node(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, 
+				  struct jffs2_raw_dirent *rd, uint32_t ofs)
+{
+	struct jffs2_raw_node_ref *raw;
+	struct jffs2_full_dirent *fd;
+	struct jffs2_inode_cache *ic;
+	uint32_t crc;
+
+	D1(printk(KERN_DEBUG "jffs2_scan_dirent_node(): Node at 0x%08x\n", ofs));
+
+	/* We don't get here unless the node is still valid, so we don't have to
+	   mask in the ACCURATE bit any more. */
+	crc = crc32(0, rd, sizeof(*rd)-8);
+
+	if (crc != je32_to_cpu(rd->node_crc)) {
+		printk(KERN_NOTICE "jffs2_scan_dirent_node(): Node CRC failed on node at 0x%08x: Read 0x%08x, calculated 0x%08x\n",
+		       ofs, je32_to_cpu(rd->node_crc), crc);
+		/* We believe totlen because the CRC on the node _header_ was OK, just the node itself failed. */
+		DIRTY_SPACE(PAD(je32_to_cpu(rd->totlen)));
+		return 0;
+	}
+
+	pseudo_random += je32_to_cpu(rd->version);
+
+	fd = jffs2_alloc_full_dirent(rd->nsize+1);
+	if (!fd) {
+		return -ENOMEM;
+	}
+	memcpy(&fd->name, rd->name, rd->nsize);
+	fd->name[rd->nsize] = 0;
+
+	crc = crc32(0, fd->name, rd->nsize);
+	if (crc != je32_to_cpu(rd->name_crc)) {
+		printk(KERN_NOTICE "jffs2_scan_dirent_node(): Name CRC failed on node at 0x%08x: Read 0x%08x, calculated 0x%08x\n",
+		       ofs, je32_to_cpu(rd->name_crc), crc);	
+		D1(printk(KERN_NOTICE "Name for which CRC failed is (now) '%s', ino #%d\n", fd->name, je32_to_cpu(rd->ino)));
+		jffs2_free_full_dirent(fd);
+		/* FIXME: Why do we believe totlen? */
+		/* We believe totlen because the CRC on the node _header_ was OK, just the name failed. */
+		DIRTY_SPACE(PAD(je32_to_cpu(rd->totlen)));
+		return 0;
+	}
+	raw = jffs2_alloc_raw_node_ref();
+	if (!raw) {
+		jffs2_free_full_dirent(fd);
+		printk(KERN_NOTICE "jffs2_scan_dirent_node(): allocation of node reference failed\n");
+		return -ENOMEM;
+	}
+	ic = jffs2_scan_make_ino_cache(c, je32_to_cpu(rd->pino));
+	if (!ic) {
+		jffs2_free_full_dirent(fd);
+		jffs2_free_raw_node_ref(raw);
+		return -ENOMEM;
+	}
+	
+	raw->__totlen = PAD(je32_to_cpu(rd->totlen));
+	raw->flash_offset = ofs | REF_PRISTINE;
+	raw->next_phys = NULL;
+	raw->next_in_ino = ic->nodes;
+	ic->nodes = raw;
+	if (!jeb->first_node)
+		jeb->first_node = raw;
+	if (jeb->last_node)
+		jeb->last_node->next_phys = raw;
+	jeb->last_node = raw;
+
+	fd->raw = raw;
+	fd->next = NULL;
+	fd->version = je32_to_cpu(rd->version);
+	fd->ino = je32_to_cpu(rd->ino);
+	fd->nhash = full_name_hash(fd->name, rd->nsize);
+	fd->type = rd->type;
+	USED_SPACE(PAD(je32_to_cpu(rd->totlen)));
+	jffs2_add_fd_to_list(c, fd, &ic->scan_dents);
+
+	return 0;
+}
+
+static int count_list(struct list_head *l)
+{
+	uint32_t count = 0;
+	struct list_head *tmp;
+
+	list_for_each(tmp, l) {
+		count++;
+	}
+	return count;
+}
+
+/* Note: This breaks if list_empty(head). I don't care. You
+   might, if you copy this code and use it elsewhere :) */
+static void rotate_list(struct list_head *head, uint32_t count)
+{
+	struct list_head *n = head->next;
+
+	list_del(head);
+	while(count--) {
+		n = n->next;
+	}
+	list_add(head, n);
+}
+
+void jffs2_rotate_lists(struct jffs2_sb_info *c)
+{
+	uint32_t x;
+	uint32_t rotateby;
+
+	x = count_list(&c->clean_list);
+	if (x) {
+		rotateby = pseudo_random % x;
+		D1(printk(KERN_DEBUG "Rotating clean_list by %d\n", rotateby));
+
+		rotate_list((&c->clean_list), rotateby);
+
+		D1(printk(KERN_DEBUG "Erase block at front of clean_list is at %08x\n",
+			  list_entry(c->clean_list.next, struct jffs2_eraseblock, list)->offset));
+	} else {
+		D1(printk(KERN_DEBUG "Not rotating empty clean_list\n"));
+	}
+
+	x = count_list(&c->very_dirty_list);
+	if (x) {
+		rotateby = pseudo_random % x;
+		D1(printk(KERN_DEBUG "Rotating very_dirty_list by %d\n", rotateby));
+
+		rotate_list((&c->very_dirty_list), rotateby);
+
+		D1(printk(KERN_DEBUG "Erase block at front of very_dirty_list is at %08x\n",
+			  list_entry(c->very_dirty_list.next, struct jffs2_eraseblock, list)->offset));
+	} else {
+		D1(printk(KERN_DEBUG "Not rotating empty very_dirty_list\n"));
+	}
+
+	x = count_list(&c->dirty_list);
+	if (x) {
+		rotateby = pseudo_random % x;
+		D1(printk(KERN_DEBUG "Rotating dirty_list by %d\n", rotateby));
+
+		rotate_list((&c->dirty_list), rotateby);
+
+		D1(printk(KERN_DEBUG "Erase block at front of dirty_list is at %08x\n",
+			  list_entry(c->dirty_list.next, struct jffs2_eraseblock, list)->offset));
+	} else {
+		D1(printk(KERN_DEBUG "Not rotating empty dirty_list\n"));
+	}
+
+	x = count_list(&c->erasable_list);
+	if (x) {
+		rotateby = pseudo_random % x;
+		D1(printk(KERN_DEBUG "Rotating erasable_list by %d\n", rotateby));
+
+		rotate_list((&c->erasable_list), rotateby);
+
+		D1(printk(KERN_DEBUG "Erase block at front of erasable_list is at %08x\n",
+			  list_entry(c->erasable_list.next, struct jffs2_eraseblock, list)->offset));
+	} else {
+		D1(printk(KERN_DEBUG "Not rotating empty erasable_list\n"));
+	}
+
+	if (c->nr_erasing_blocks) {
+		rotateby = pseudo_random % c->nr_erasing_blocks;
+		D1(printk(KERN_DEBUG "Rotating erase_pending_list by %d\n", rotateby));
+
+		rotate_list((&c->erase_pending_list), rotateby);
+
+		D1(printk(KERN_DEBUG "Erase block at front of erase_pending_list is at %08x\n",
+			  list_entry(c->erase_pending_list.next, struct jffs2_eraseblock, list)->offset));
+	} else {
+		D1(printk(KERN_DEBUG "Not rotating empty erase_pending_list\n"));
+	}
+
+	if (c->nr_free_blocks) {
+		rotateby = pseudo_random % c->nr_free_blocks;
+		D1(printk(KERN_DEBUG "Rotating free_list by %d\n", rotateby));
+
+		rotate_list((&c->free_list), rotateby);
+
+		D1(printk(KERN_DEBUG "Erase block at front of free_list is at %08x\n",
+			  list_entry(c->free_list.next, struct jffs2_eraseblock, list)->offset));
+	} else {
+		D1(printk(KERN_DEBUG "Not rotating empty free_list\n"));
+	}
+}