/*
-------------------------------------------------------------------------
 * Filename:      jffs2.c
 * Version:       $Id: jffs2_1pass.c,v 1.7 2002/01/25 01:56:47 nyet Exp $
 * Copyright:     Copyright (C) 2001, Russ Dill
 * Author:        Russ Dill <Russ.Dill@asu.edu>
 * Description:   Module to load kernel from jffs2
 *-----------------------------------------------------------------------*/
/*
 * some portions of this code are taken from jffs2, and as such, the
 * following copyright notice is included.
 *
 * JFFS2 -- Journalling Flash File System, Version 2.
 *
 * Copyright (C) 2001 Red Hat, Inc.
 *
 * Created by David Woodhouse <dwmw2@cambridge.redhat.com>
 *
 * The original JFFS, from which the design for JFFS2 was derived,
 * was designed and implemented by Axis Communications AB.
 *
 * The contents of this file are subject to the Red Hat eCos Public
 * License Version 1.1 (the "Licence"); you may not use this file
 * except in compliance with the Licence.  You may obtain a copy of
 * the Licence at http://www.redhat.com/
 *
 * Software distributed under the Licence is distributed on an "AS IS"
 * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied.
 * See the Licence for the specific language governing rights and
 * limitations under the Licence.
 *
 * The Original Code is JFFS2 - Journalling Flash File System, version 2
 *
 * Alternatively, the contents of this file may be used under the
 * terms of the GNU General Public License version 2 (the "GPL"), in
 * which case the provisions of the GPL are applicable instead of the
 * above.  If you wish to allow the use of your version of this file
 * only under the terms of the GPL and not to allow others to use your
 * version of this file under the RHEPL, indicate your decision by
 * deleting the provisions above and replace them with the notice and
 * other provisions required by the GPL.  If you do not delete the
 * provisions above, a recipient may use your version of this file
 * under either the RHEPL or the GPL.
 *
 * $Id: jffs2_1pass.c,v 1.7 2002/01/25 01:56:47 nyet Exp $
 *
 */

/* Ok, so anyone who knows the jffs2 code will probably want to get a papar
 * bag to throw up into before reading this code. I looked through the jffs2
 * code, the caching scheme is very elegant. I tried to keep the version
 * for a bootloader as small and simple as possible. Instead of worring about
 * unneccesary data copies, node scans, etc, I just optimized for the known
 * common case, a kernel, which looks like:
 *      (1) most pages are 4096 bytes
 *      (2) version numbers are somewhat sorted in acsending order
 *      (3) multiple compressed blocks making up one page is uncommon
 *
 * So I create a linked list of decending version numbers (insertions at the
 * head), and then for each page, walk down the list, until a matching page
 * with 4096 bytes is found, and then decompress the watching pages in
 * reverse order.
 *
 */

/*
 * Adapted by Nye Liu <nyet@zumanetworks.com> and
 * Rex Feany <rfeany@zumanetworks.com>
 * on Jan/2002 for U-Boot.
 *
 * Clipped out all the non-1pass functions, cleaned up warnings,
 * wrappers, etc. No major changes to the code.
 * Please, he really means it when he said have a paper bag
 * handy. We needed it ;).
 *
 */

/*
 * Bugfixing by Kai-Uwe Bloem <kai-uwe.bloem@auerswald.de>, (C) Mar/2003
 *
 * - overhaul of the memory management. Removed much of the "paper-bagging"
 *   in that part of the code, fixed several bugs, now frees memory when
 *   partition is changed.
 *   It's still ugly :-(
 * - fixed a bug in jffs2_1pass_read_inode where the file length calculation
 *   was incorrect. Removed a bit of the paper-bagging as well.
 * - removed double crc calculation for fragment headers in jffs2_private.h
 *   for speedup.
 * - scan_empty rewritten in a more "standard" manner (non-paperbag, that is).
 * - spinning wheel now spins depending on how much memory has been scanned
 * - lots of small changes all over the place to "improve" readability.
 * - implemented fragment sorting to ensure that the newest data is copied
 *   if there are multiple copies of fragments for a certain file offset.
 *
 * The fragment sorting feature must be enabled by CONFIG_SYS_JFFS2_SORT_FRAGMENTS.
 * Sorting is done while adding fragments to the lists, which is more or less a
 * bubble sort. This takes a lot of time, and is most probably not an issue if
 * the boot filesystem is always mounted readonly.
 *
 * You should define it if the boot filesystem is mounted writable, and updates
 * to the boot files are done by copying files to that filesystem.
 *
 *
 * There's a big issue left: endianess is completely ignored in this code. Duh!
 *
 *
 * You still should have paper bags at hand :-(. The code lacks more or less
 * any comment, and is still arcane and difficult to read in places. As this
 * might be incompatible with any new code from the jffs2 maintainers anyway,
 * it should probably be dumped and replaced by something like jffs2reader!
 */


#include <common.h>
#include <config.h>
#include <malloc.h>
#include <div64.h>
#include <linux/compiler.h>
#include <linux/stat.h>
#include <linux/time.h>
#include <watchdog.h>
#include <jffs2/jffs2.h>
#include <jffs2/jffs2_1pass.h>
#include <linux/compat.h>
#include <linux/errno.h>

#include "jffs2_private.h"


#define NODE_CHUNK      1024    /* size of memory allocation chunk in b_nodes */
#define SPIN_BLKSIZE    18      /* spin after having scanned 1<<BLKSIZE bytes */

/* Debugging switches */
#undef  DEBUG_DIRENTS           /* print directory entry list after scan */
#undef  DEBUG_FRAGMENTS         /* print fragment list after scan */
#undef  DEBUG                   /* enable debugging messages */


#ifdef  DEBUG
# define DEBUGF(fmt,args...)    printf(fmt ,##args)
#else
# define DEBUGF(fmt,args...)
#endif

#include "summary.h"

/* keeps pointer to currentlu processed partition */
static struct part_info *current_part;

#if (defined(CONFIG_JFFS2_NAND) && \
     defined(CONFIG_CMD_NAND) )
#include <nand.h>
/*
 * Support for jffs2 on top of NAND-flash
 *
 * NAND memory isn't mapped in processor's address space,
 * so data should be fetched from flash before
 * being processed. This is exactly what functions declared
 * here do.
 *
 */

#define NAND_PAGE_SIZE 512
#define NAND_PAGE_SHIFT 9
#define NAND_PAGE_MASK (~(NAND_PAGE_SIZE-1))

#ifndef NAND_CACHE_PAGES
#define NAND_CACHE_PAGES 16
#endif
#define NAND_CACHE_SIZE (NAND_CACHE_PAGES*NAND_PAGE_SIZE)

static u8* nand_cache = NULL;
static u32 nand_cache_off = (u32)-1;

static int read_nand_cached(u32 off, u32 size, u_char *buf)
{
        struct mtdids *id = current_part->dev->id;
        struct mtd_info *mtd;
        u32 bytes_read = 0;
        size_t retlen;
        int cpy_bytes;

        mtd = get_nand_dev_by_index(id->num);
        if (!mtd)
                return -1;

        while (bytes_read < size) {
                if ((off + bytes_read < nand_cache_off) ||
                    (off + bytes_read >= nand_cache_off+NAND_CACHE_SIZE)) {
                        nand_cache_off = (off + bytes_read) & NAND_PAGE_MASK;
                        if (!nand_cache) {
                                /* This memory never gets freed but 'cause
                                   it's a bootloader, nobody cares */
                                nand_cache = malloc(NAND_CACHE_SIZE);
                                if (!nand_cache) {
                                        printf("read_nand_cached: can't alloc cache size %d bytes\n",
                                               NAND_CACHE_SIZE);
                                        return -1;
                                }
                        }

                        retlen = NAND_CACHE_SIZE;
                        if (nand_read(mtd, nand_cache_off,
                                      &retlen, nand_cache) < 0 ||
                                        retlen != NAND_CACHE_SIZE) {
                                printf("read_nand_cached: error reading nand off %#x size %d bytes\n",
                                                nand_cache_off, NAND_CACHE_SIZE);
                                return -1;
                        }
                }
                cpy_bytes = nand_cache_off + NAND_CACHE_SIZE - (off + bytes_read);
                if (cpy_bytes > size - bytes_read)
                        cpy_bytes = size - bytes_read;
                memcpy(buf + bytes_read,
                       nand_cache + off + bytes_read - nand_cache_off,
                       cpy_bytes);
                bytes_read += cpy_bytes;
        }
        return bytes_read;
}

static void *get_fl_mem_nand(u32 off, u32 size, void *ext_buf)
{
        u_char *buf = ext_buf ? (u_char*)ext_buf : (u_char*)malloc(size);

        if (NULL == buf) {
                printf("get_fl_mem_nand: can't alloc %d bytes\n", size);
                return NULL;
        }
        if (read_nand_cached(off, size, buf) < 0) {
                if (!ext_buf)
                        free(buf);
                return NULL;
        }

        return buf;
}

static void *get_node_mem_nand(u32 off, void *ext_buf)
{
        struct jffs2_unknown_node node;
        void *ret = NULL;

        if (NULL == get_fl_mem_nand(off, sizeof(node), &node))
                return NULL;

        if (!(ret = get_fl_mem_nand(off, node.magic ==
                               JFFS2_MAGIC_BITMASK ? node.totlen : sizeof(node),
                               ext_buf))) {
                printf("off = %#x magic %#x type %#x node.totlen = %d\n",
                       off, node.magic, node.nodetype, node.totlen);
        }
        return ret;
}

static void put_fl_mem_nand(void *buf)
{
        free(buf);
}
#endif

#if defined(CONFIG_CMD_ONENAND)

#include <linux/mtd/mtd.h>
#include <linux/mtd/onenand.h>
#include <onenand_uboot.h>

#define ONENAND_PAGE_SIZE 2048
#define ONENAND_PAGE_SHIFT 11
#define ONENAND_PAGE_MASK (~(ONENAND_PAGE_SIZE-1))

#ifndef ONENAND_CACHE_PAGES
#define ONENAND_CACHE_PAGES 4
#endif
#define ONENAND_CACHE_SIZE (ONENAND_CACHE_PAGES*ONENAND_PAGE_SIZE)

static u8* onenand_cache;
static u32 onenand_cache_off = (u32)-1;

static int read_onenand_cached(u32 off, u32 size, u_char *buf)
{
        u32 bytes_read = 0;
        size_t retlen;
        int cpy_bytes;

        while (bytes_read < size) {
                if ((off + bytes_read < onenand_cache_off) ||
                    (off + bytes_read >= onenand_cache_off + ONENAND_CACHE_SIZE)) {
                        onenand_cache_off = (off + bytes_read) & ONENAND_PAGE_MASK;
                        if (!onenand_cache) {
                                /* This memory never gets freed but 'cause
                                   it's a bootloader, nobody cares */
                                onenand_cache = malloc(ONENAND_CACHE_SIZE);
                                if (!onenand_cache) {
                                        printf("read_onenand_cached: can't alloc cache size %d bytes\n",
                                               ONENAND_CACHE_SIZE);
                                        return -1;
                                }
                        }

                        retlen = ONENAND_CACHE_SIZE;
                        if (onenand_read(&onenand_mtd, onenand_cache_off, retlen,
                                                &retlen, onenand_cache) < 0 ||
                                        retlen != ONENAND_CACHE_SIZE) {
                                printf("read_onenand_cached: error reading nand off %#x size %d bytes\n",
                                        onenand_cache_off, ONENAND_CACHE_SIZE);
                                return -1;
                        }
                }
                cpy_bytes = onenand_cache_off + ONENAND_CACHE_SIZE - (off + bytes_read);
                if (cpy_bytes > size - bytes_read)
                        cpy_bytes = size - bytes_read;
                memcpy(buf + bytes_read,
                       onenand_cache + off + bytes_read - onenand_cache_off,
                       cpy_bytes);
                bytes_read += cpy_bytes;
        }
        return bytes_read;
}

static void *get_fl_mem_onenand(u32 off, u32 size, void *ext_buf)
{
        u_char *buf = ext_buf ? (u_char *)ext_buf : (u_char *)malloc(size);

        if (NULL == buf) {
                printf("get_fl_mem_onenand: can't alloc %d bytes\n", size);
                return NULL;
        }
        if (read_onenand_cached(off, size, buf) < 0) {
                if (!ext_buf)
                        free(buf);
                return NULL;
        }

        return buf;
}

static void *get_node_mem_onenand(u32 off, void *ext_buf)
{
        struct jffs2_unknown_node node;
        void *ret = NULL;

        if (NULL == get_fl_mem_onenand(off, sizeof(node), &node))
                return NULL;

        ret = get_fl_mem_onenand(off, node.magic ==
                        JFFS2_MAGIC_BITMASK ? node.totlen : sizeof(node),
                        ext_buf);
        if (!ret) {
                printf("off = %#x magic %#x type %#x node.totlen = %d\n",
                       off, node.magic, node.nodetype, node.totlen);
        }
        return ret;
}


static void put_fl_mem_onenand(void *buf)
{
        free(buf);
}
#endif


#if defined(CONFIG_CMD_FLASH)
/*
 * Support for jffs2 on top of NOR-flash
 *
 * NOR flash memory is mapped in processor's address space,
 * just return address.
 */
static inline void *get_fl_mem_nor(u32 off, u32 size, void *ext_buf)
{
        u32 addr = off;
        struct mtdids *id = current_part->dev->id;

        extern flash_info_t flash_info[];
        flash_info_t *flash = &flash_info[id->num];

        addr += flash->start[0];
        if (ext_buf) {
                memcpy(ext_buf, (void *)addr, size);
                return ext_buf;
        }
        return (void*)addr;
}

static inline void *get_node_mem_nor(u32 off, void *ext_buf)
{
        struct jffs2_unknown_node *pNode;

        /* pNode will point directly to flash - don't provide external buffer
           and don't care about size */
        pNode = get_fl_mem_nor(off, 0, NULL);
        return (void *)get_fl_mem_nor(off, pNode->magic == JFFS2_MAGIC_BITMASK ?
                        pNode->totlen : sizeof(*pNode), ext_buf);
}
#endif


/*
 * Generic jffs2 raw memory and node read routines.
 *
 */
static inline void *get_fl_mem(u32 off, u32 size, void *ext_buf)
{
        struct mtdids *id = current_part->dev->id;

        switch(id->type) {
#if defined(CONFIG_CMD_FLASH)
        case MTD_DEV_TYPE_NOR:
                return get_fl_mem_nor(off, size, ext_buf);
                break;
#endif
#if defined(CONFIG_JFFS2_NAND) && defined(CONFIG_CMD_NAND)
        case MTD_DEV_TYPE_NAND:
                return get_fl_mem_nand(off, size, ext_buf);
                break;
#endif
#if defined(CONFIG_CMD_ONENAND)
        case MTD_DEV_TYPE_ONENAND:
                return get_fl_mem_onenand(off, size, ext_buf);
                break;
#endif
        default:
                printf("get_fl_mem: unknown device type, " \
                        "using raw offset!\n");
        }
        return (void*)off;
}

static inline void *get_node_mem(u32 off, void *ext_buf)
{
        struct mtdids *id = current_part->dev->id;

        switch(id->type) {
#if defined(CONFIG_CMD_FLASH)
        case MTD_DEV_TYPE_NOR:
                return get_node_mem_nor(off, ext_buf);
                break;
#endif
#if defined(CONFIG_JFFS2_NAND) && \
    defined(CONFIG_CMD_NAND)
        case MTD_DEV_TYPE_NAND:
                return get_node_mem_nand(off, ext_buf);
                break;
#endif
#if defined(CONFIG_CMD_ONENAND)
        case MTD_DEV_TYPE_ONENAND:
                return get_node_mem_onenand(off, ext_buf);
                break;
#endif
        default:
                printf("get_fl_mem: unknown device type, " \
                        "using raw offset!\n");
        }
        return (void*)off;
}

static inline void put_fl_mem(void *buf, void *ext_buf)
{
        struct mtdids *id = current_part->dev->id;

        /* If buf is the same as ext_buf, it was provided by the caller -
           we shouldn't free it then. */
        if (buf == ext_buf)
                return;
        switch (id->type) {
#if defined(CONFIG_JFFS2_NAND) && defined(CONFIG_CMD_NAND)
        case MTD_DEV_TYPE_NAND:
                return put_fl_mem_nand(buf);
#endif
#if defined(CONFIG_CMD_ONENAND)
        case MTD_DEV_TYPE_ONENAND:
                return put_fl_mem_onenand(buf);
#endif
        }
}

/* Compression names */
static char *compr_names[] = {
        "NONE",
        "ZERO",
        "RTIME",
        "RUBINMIPS",
        "COPY",
        "DYNRUBIN",
        "ZLIB",
#if defined(CONFIG_JFFS2_LZO)
        "LZO",
#endif
};

/* Memory management */
struct mem_block {
        u32     index;
        struct mem_block *next;
        struct b_node nodes[NODE_CHUNK];
};


static void
free_nodes(struct b_list *list)
{
        while (list->listMemBase != NULL) {
                struct mem_block *next = list->listMemBase->next;
                free( list->listMemBase );
                list->listMemBase = next;
        }
}

static struct b_node *
add_node(struct b_list *list)
{
        u32 index = 0;
        struct mem_block *memBase;
        struct b_node *b;

        memBase = list->listMemBase;
        if (memBase != NULL)
                index = memBase->index;
#if 0
        putLabeledWord("add_node: index = ", index);
        putLabeledWord("add_node: memBase = ", list->listMemBase);
#endif

        if (memBase == NULL || index >= NODE_CHUNK) {
                /* we need more space before we continue */
                memBase = mmalloc(sizeof(struct mem_block));
                if (memBase == NULL) {
                        putstr("add_node: malloc failed\n");
                        return NULL;
                }
                memBase->next = list->listMemBase;
                index = 0;
#if 0
                putLabeledWord("add_node: alloced a new membase at ", *memBase);
#endif

        }
        /* now we have room to add it. */
        b = &memBase->nodes[index];
        index ++;

        memBase->index = index;
        list->listMemBase = memBase;
        list->listCount++;
        return b;
}

static struct b_node *
insert_node(struct b_list *list, u32 offset)
{
        struct b_node *new;

        if (!(new = add_node(list))) {
                putstr("add_node failed!\r\n");
                return NULL;
        }
        new->offset = offset;
        new->next = NULL;

        if (list->listTail != NULL)
                list->listTail->next = new;
        else
                list->listHead = new;
        list->listTail = new;

        return new;
}

#ifdef CONFIG_SYS_JFFS2_SORT_FRAGMENTS
/* Sort data entries with the latest version last, so that if there
 * is overlapping data the latest version will be used.
 */
static int compare_inodes(struct b_node *new, struct b_node *old)
{
        /*
         * Only read in the version info from flash, not the entire inode.
         * This can make a big difference to speed if flash is slow.
         */
        u32 new_version;
        u32 old_version;
        get_fl_mem(new->offset + offsetof(struct jffs2_raw_inode, version),
                   sizeof(new_version), &new_version);
        get_fl_mem(old->offset + offsetof(struct jffs2_raw_inode, version),
                   sizeof(old_version), &old_version);

        return new_version > old_version;
}

/* Sort directory entries so all entries in the same directory
 * with the same name are grouped together, with the latest version
 * last. This makes it easy to eliminate all but the latest version
 * by marking the previous version dead by setting the inode to 0.
 */
static int compare_dirents(struct b_node *new, struct b_node *old)
{
        /*
         * Using NULL as the buffer for NOR flash prevents the entire node
         * being read. This makes most comparisons much quicker as only one
         * or two entries from the node will be used most of the time.
         */
        struct jffs2_raw_dirent *jNew = get_node_mem(new->offset, NULL);
        struct jffs2_raw_dirent *jOld = get_node_mem(old->offset, NULL);
        int cmp;
        int ret;

        if (jNew->pino != jOld->pino) {
                /* ascending sort by pino */
                ret = jNew->pino > jOld->pino;
        } else if (jNew->nsize != jOld->nsize) {
                /*
                 * pino is the same, so use ascending sort by nsize,
                 * so we don't do strncmp unless we really must.
                 */
                ret = jNew->nsize > jOld->nsize;
        } else {
                /*
                 * length is also the same, so use ascending sort by name
                 */
                cmp = strncmp((char *)jNew->name, (char *)jOld->name,
                        jNew->nsize);
                if (cmp != 0) {
                        ret = cmp > 0;
                } else {
                        /*
                         * we have duplicate names in this directory,
                         * so use ascending sort by version
                         */
                        ret = jNew->version > jOld->version;
                }
        }
        put_fl_mem(jNew, NULL);
        put_fl_mem(jOld, NULL);

        return ret;
}
#endif

void
jffs2_free_cache(struct part_info *part)
{
        struct b_lists *pL;

        if (part->jffs2_priv != NULL) {
                pL = (struct b_lists *)part->jffs2_priv;
                free_nodes(&pL->frag);
                free_nodes(&pL->dir);
                free(pL->readbuf);
                free(pL);
        }
}

static u32
jffs_init_1pass_list(struct part_info *part)
{
        struct b_lists *pL;

        jffs2_free_cache(part);

        if (NULL != (part->jffs2_priv = malloc(sizeof(struct b_lists)))) {
                pL = (struct b_lists *)part->jffs2_priv;

                memset(pL, 0, sizeof(*pL));
#ifdef CONFIG_SYS_JFFS2_SORT_FRAGMENTS
                pL->dir.listCompare = compare_dirents;
                pL->frag.listCompare = compare_inodes;
#endif
        }
        return 0;
}

/* find the inode from the slashless name given a parent */
static long
jffs2_1pass_read_inode(struct b_lists *pL, u32 inode, char *dest)
{
        struct b_node *b;
        struct jffs2_raw_inode *jNode;
        u32 totalSize = 0;
        u32 latestVersion = 0;
        uchar *lDest;
        uchar *src;
        int i;
        u32 counter = 0;
#ifdef CONFIG_SYS_JFFS2_SORT_FRAGMENTS
        /* Find file size before loading any data, so fragments that
         * start past the end of file can be ignored. A fragment
         * that is partially in the file is loaded, so extra data may
         * be loaded up to the next 4K boundary above the file size.
         * This shouldn't cause trouble when loading kernel images, so
         * we will live with it.
         */
        for (b = pL->frag.listHead; b != NULL; b = b->next) {
                jNode = (struct jffs2_raw_inode *) get_fl_mem(b->offset,
                        sizeof(struct jffs2_raw_inode), pL->readbuf);
                if ((inode == jNode->ino)) {
                        /* get actual file length from the newest node */
                        if (jNode->version >= latestVersion) {
                                totalSize = jNode->isize;
                                latestVersion = jNode->version;
                        }
                }
                put_fl_mem(jNode, pL->readbuf);
        }
        /*
         * If no destination is provided, we are done.
         * Just return the total size.
         */
        if (!dest)
                return totalSize;
#endif

        for (b = pL->frag.listHead; b != NULL; b = b->next) {
                /*
                 * Copy just the node and not the data at this point,
                 * since we don't yet know if we need this data.
                 */
                jNode = (struct jffs2_raw_inode *)get_fl_mem(b->offset,
                                sizeof(struct jffs2_raw_inode),
                                pL->readbuf);
                if (inode == jNode->ino) {
#if 0
                        putLabeledWord("\r\n\r\nread_inode: totlen = ", jNode->totlen);
                        putLabeledWord("read_inode: inode = ", jNode->ino);
                        putLabeledWord("read_inode: version = ", jNode->version);
                        putLabeledWord("read_inode: isize = ", jNode->isize);
                        putLabeledWord("read_inode: offset = ", jNode->offset);
                        putLabeledWord("read_inode: csize = ", jNode->csize);
                        putLabeledWord("read_inode: dsize = ", jNode->dsize);
                        putLabeledWord("read_inode: compr = ", jNode->compr);
                        putLabeledWord("read_inode: usercompr = ", jNode->usercompr);
                        putLabeledWord("read_inode: flags = ", jNode->flags);
#endif

#ifndef CONFIG_SYS_JFFS2_SORT_FRAGMENTS
                        /* get actual file length from the newest node */
                        if (jNode->version >= latestVersion) {
                                totalSize = jNode->isize;
                                latestVersion = jNode->version;
                        }
#endif

                        if(dest) {
                                /*
                                 * Now that the inode has been checked,
                                 * read the entire inode, including data.
                                 */
                                put_fl_mem(jNode, pL->readbuf);
                                jNode = (struct jffs2_raw_inode *)
                                        get_node_mem(b->offset, pL->readbuf);
                                src = ((uchar *)jNode) +
                                        sizeof(struct jffs2_raw_inode);
                                /* ignore data behind latest known EOF */
                                if (jNode->offset > totalSize) {
                                        put_fl_mem(jNode, pL->readbuf);
                                        continue;
                                }
                                if (b->datacrc == CRC_UNKNOWN)
                                        b->datacrc = data_crc(jNode) ?
                                                CRC_OK : CRC_BAD;
                                if (b->datacrc == CRC_BAD) {
                                        put_fl_mem(jNode, pL->readbuf);
                                        continue;
                                }

                                lDest = (uchar *) (dest + jNode->offset);
#if 0
                                putLabeledWord("read_inode: src = ", src);
                                putLabeledWord("read_inode: dest = ", lDest);
#endif
                                switch (jNode->compr) {
                                case JFFS2_COMPR_NONE:
                                        ldr_memcpy(lDest, src, jNode->dsize);
                                        break;
                                case JFFS2_COMPR_ZERO:
                                        for (i = 0; i < jNode->dsize; i++)
                                                *(lDest++) = 0;
                                        break;
                                case JFFS2_COMPR_RTIME:
                                        rtime_decompress(src, lDest, jNode->csize, jNode->dsize);
                                        break;
                                case JFFS2_COMPR_DYNRUBIN:
                                        /* this is slow but it works */
                                        dynrubin_decompress(src, lDest, jNode->csize, jNode->dsize);
                                        break;
                                case JFFS2_COMPR_ZLIB:
                                        zlib_decompress(src, lDest, jNode->csize, jNode->dsize);
                                        break;
#if defined(CONFIG_JFFS2_LZO)
                                case JFFS2_COMPR_LZO:
                                        lzo_decompress(src, lDest, jNode->csize, jNode->dsize);
                                        break;
#endif
                                default:
                                        /* unknown */
                                        putLabeledWord("UNKNOWN COMPRESSION METHOD = ", jNode->compr);
                                        put_fl_mem(jNode, pL->readbuf);
                                        return -1;
                                        break;
                                }
                        }

#if 0
                        putLabeledWord("read_inode: totalSize = ", totalSize);
#endif
                }
                counter++;
                put_fl_mem(jNode, pL->readbuf);
        }

#if 0
        putLabeledWord("read_inode: returning = ", totalSize);
#endif
        return totalSize;
}

/* find the inode from the slashless name given a parent */
static u32
jffs2_1pass_find_inode(struct b_lists * pL, const char *name, u32 pino)
{
        struct b_node *b;
        struct jffs2_raw_dirent *jDir;
        int len;
        u32 counter;
        u32 version = 0;
        u32 inode = 0;

        /* name is assumed slash free */
        len = strlen(name);

        counter = 0;
        /* we need to search all and return the inode with the highest version */
        for(b = pL->dir.listHead; b; b = b->next, counter++) {
                jDir = (struct jffs2_raw_dirent *) get_node_mem(b->offset,
                                                                pL->readbuf);
                if ((pino == jDir->pino) && (len == jDir->nsize) &&
                    (!strncmp((char *)jDir->name, name, len))) {        /* a match */
                        if (jDir->version < version) {
                                put_fl_mem(jDir, pL->readbuf);
                                continue;
                        }

                        if (jDir->version == version && inode != 0) {
                                /* I'm pretty sure this isn't legal */
                                putstr(" ** ERROR ** ");
                                putnstr(jDir->name, jDir->nsize);
                                putLabeledWord(" has dup version =", version);
                        }
                        inode = jDir->ino;
                        version = jDir->version;
                }
#if 0
                putstr("\r\nfind_inode:p&l ->");
                putnstr(jDir->name, jDir->nsize);
                putstr("\r\n");
                putLabeledWord("pino = ", jDir->pino);
                putLabeledWord("nsize = ", jDir->nsize);
                putLabeledWord("b = ", (u32) b);
                putLabeledWord("counter = ", counter);
#endif
                put_fl_mem(jDir, pL->readbuf);
        }
        return inode;
}

char *mkmodestr(unsigned long mode, char *str)
{
        static const char *l = "xwr";
        int mask = 1, i;
        char c;

        switch (mode & S_IFMT) {
                case S_IFDIR:    str[0] = 'd'; break;
                case S_IFBLK:    str[0] = 'b'; break;
                case S_IFCHR:    str[0] = 'c'; break;
                case S_IFIFO:    str[0] = 'f'; break;
                case S_IFLNK:    str[0] = 'l'; break;
                case S_IFSOCK:   str[0] = 's'; break;
                case S_IFREG:    str[0] = '-'; break;
                default:         str[0] = '?';
        }

        for(i = 0; i < 9; i++) {
                c = l[i%3];
                str[9-i] = (mode & mask)?c:'-';
                mask = mask<<1;
        }

        if(mode & S_ISUID) str[3] = (mode & S_IXUSR)?'s':'S';
        if(mode & S_ISGID) str[6] = (mode & S_IXGRP)?'s':'S';
        if(mode & S_ISVTX) str[9] = (mode & S_IXOTH)?'t':'T';
        str[10] = '\0';
        return str;
}

static inline void dump_stat(struct stat *st, const char *name)
{
        char str[20];
        char s[64], *p;

        if (st->st_mtime == (time_t)(-1)) /* some ctimes really hate -1 */
                st->st_mtime = 1;

        ctime_r((time_t *)&st->st_mtime, s/*,64*/); /* newlib ctime doesn't have buflen */

        if ((p = strchr(s,'\n')) != NULL) *p = '\0';
        if ((p = strchr(s,'\r')) != NULL) *p = '\0';

/*
        printf("%6lo %s %8ld %s %s\n", st->st_mode, mkmodestr(st->st_mode, str),
                st->st_size, s, name);
*/

        printf(" %s %8ld %s %s", mkmodestr(st->st_mode,str), st->st_size, s, name);
}

static inline u32 dump_inode(struct b_lists * pL, struct jffs2_raw_dirent *d, struct jffs2_raw_inode *i)
{
        char fname[256];
        struct stat st;

        if(!d || !i) return -1;

        strncpy(fname, (char *)d->name, d->nsize);
        fname[d->nsize] = '\0';

        memset(&st,0,sizeof(st));

        st.st_mtime = i->mtime;
        st.st_mode = i->mode;
        st.st_ino = i->ino;
        st.st_size = i->isize;

        dump_stat(&st, fname);

        if (d->type == DT_LNK) {
                unsigned char *src = (unsigned char *) (&i[1]);
                putstr(" -> ");
                putnstr(src, (int)i->dsize);
        }

        putstr("\r\n");

        return 0;
}

/* list inodes with the given pino */
static u32
jffs2_1pass_list_inodes(struct b_lists * pL, u32 pino)
{
        struct b_node *b;
        struct jffs2_raw_dirent *jDir;

        for (b = pL->dir.listHead; b; b = b->next) {
                jDir = (struct jffs2_raw_dirent *) get_node_mem(b->offset,
                                                                pL->readbuf);
                if (pino == jDir->pino) {
                        u32 i_version = 0;
                        struct jffs2_raw_inode *jNode, *i = NULL;
                        struct b_node *b2;

#ifdef CONFIG_SYS_JFFS2_SORT_FRAGMENTS
                        /* Check for more recent versions of this file */
                        int match;
                        do {
                                struct b_node *next = b->next;
                                struct jffs2_raw_dirent *jDirNext;
                                if (!next)
                                        break;
                                jDirNext = (struct jffs2_raw_dirent *)
                                        get_node_mem(next->offset, NULL);
                                match = jDirNext->pino == jDir->pino &&
                                        jDirNext->nsize == jDir->nsize &&
                                        strncmp((char *)jDirNext->name,
                                                (char *)jDir->name,
                                                jDir->nsize) == 0;
                                if (match) {
                                        /* Use next. It is more recent */
                                        b = next;
                                        /* Update buffer with the new info */
                                        *jDir = *jDirNext;
                                }
                                put_fl_mem(jDirNext, NULL);
                        } while (match);
#endif
                        if (jDir->ino == 0) {
                                /* Deleted file */
                                put_fl_mem(jDir, pL->readbuf);
                                continue;
                        }

                        for (b2 = pL->frag.listHead; b2; b2 = b2->next) {
                                jNode = (struct jffs2_raw_inode *)
                                        get_fl_mem(b2->offset, sizeof(*jNode),
                                                   NULL);
                                if (jNode->ino == jDir->ino &&
                                    jNode->version >= i_version) {
                                        i_version = jNode->version;
                                        if (i)
                                                put_fl_mem(i, NULL);

                                        if (jDir->type == DT_LNK)
                                                i = get_node_mem(b2->offset,
                                                                 NULL);
                                        else
                                                i = get_fl_mem(b2->offset,
                                                               sizeof(*i),
                                                               NULL);
                                }
                                put_fl_mem(jNode, NULL);
                        }

                        dump_inode(pL, jDir, i);
                        put_fl_mem(i, NULL);
                }
                put_fl_mem(jDir, pL->readbuf);
        }
        return pino;
}

static u32
jffs2_1pass_search_inode(struct b_lists * pL, const char *fname, u32 pino)
{
        int i;
        char tmp[256];
        char working_tmp[256];
        char *c;

        /* discard any leading slash */
        i = 0;
        while (fname[i] == '/')
                i++;
        strcpy(tmp, &fname[i]);

        while ((c = (char *) strchr(tmp, '/'))) /* we are still dired searching */
        {
                strncpy(working_tmp, tmp, c - tmp);
                working_tmp[c - tmp] = '\0';
#if 0
                putstr("search_inode: tmp = ");
                putstr(tmp);
                putstr("\r\n");
                putstr("search_inode: wtmp = ");
                putstr(working_tmp);
                putstr("\r\n");
                putstr("search_inode: c = ");
                putstr(c);
                putstr("\r\n");
#endif
                for (i = 0; i < strlen(c) - 1; i++)
                        tmp[i] = c[i + 1];
                tmp[i] = '\0';
#if 0
                putstr("search_inode: post tmp = ");
                putstr(tmp);
                putstr("\r\n");
#endif

                if (!(pino = jffs2_1pass_find_inode(pL, working_tmp, pino))) {
                        putstr("find_inode failed for name=");
                        putstr(working_tmp);
                        putstr("\r\n");
                        return 0;
                }
        }
        /* this is for the bare filename, directories have already been mapped */
        if (!(pino = jffs2_1pass_find_inode(pL, tmp, pino))) {
                putstr("find_inode failed for name=");
                putstr(tmp);
                putstr("\r\n");
                return 0;
        }
        return pino;

}

static u32
jffs2_1pass_resolve_inode(struct b_lists * pL, u32 ino)
{
        struct b_node *b;
        struct b_node *b2;
        struct jffs2_raw_dirent *jDir;
        struct jffs2_raw_inode *jNode;
        u8 jDirFoundType = 0;
        u32 jDirFoundIno = 0;
        u32 jDirFoundPino = 0;
        char tmp[256];
        u32 version = 0;
        u32 pino;
        unsigned char *src;

        /* we need to search all and return the inode with the highest version */
        for(b = pL->dir.listHead; b; b = b->next) {
                jDir = (struct jffs2_raw_dirent *) get_node_mem(b->offset,
                                                                pL->readbuf);
                if (ino == jDir->ino) {
                        if (jDir->version < version) {
                                put_fl_mem(jDir, pL->readbuf);
                                continue;
                        }

                        if (jDir->version == version && jDirFoundType) {
                                /* I'm pretty sure this isn't legal */
                                putstr(" ** ERROR ** ");
                                putnstr(jDir->name, jDir->nsize);
                                putLabeledWord(" has dup version (resolve) = ",
                                        version);
                        }

                        jDirFoundType = jDir->type;
                        jDirFoundIno = jDir->ino;
                        jDirFoundPino = jDir->pino;
                        version = jDir->version;
                }
                put_fl_mem(jDir, pL->readbuf);
        }
        /* now we found the right entry again. (shoulda returned inode*) */
        if (jDirFoundType != DT_LNK)
                return jDirFoundIno;

        /* it's a soft link so we follow it again. */
        b2 = pL->frag.listHead;
        while (b2) {
                jNode = (struct jffs2_raw_inode *) get_node_mem(b2->offset,
                                                                pL->readbuf);
                if (jNode->ino == jDirFoundIno) {
                        src = (unsigned char *)jNode + sizeof(struct jffs2_raw_inode);

#if 0
                        putLabeledWord("\t\t dsize = ", jNode->dsize);
                        putstr("\t\t target = ");
                        putnstr(src, jNode->dsize);
                        putstr("\r\n");
#endif
                        strncpy(tmp, (char *)src, jNode->dsize);
                        tmp[jNode->dsize] = '\0';
                        put_fl_mem(jNode, pL->readbuf);
                        break;
                }
                b2 = b2->next;
                put_fl_mem(jNode, pL->readbuf);
        }
        /* ok so the name of the new file to find is in tmp */
        /* if it starts with a slash it is root based else shared dirs */
        if (tmp[0] == '/')
                pino = 1;
        else
                pino = jDirFoundPino;

        return jffs2_1pass_search_inode(pL, tmp, pino);
}

static u32
jffs2_1pass_search_list_inodes(struct b_lists * pL, const char *fname, u32 pino)
{
        int i;
        char tmp[256];
        char working_tmp[256];
        char *c;

        /* discard any leading slash */
        i = 0;
        while (fname[i] == '/')
                i++;
        strcpy(tmp, &fname[i]);
        working_tmp[0] = '\0';
        while ((c = (char *) strchr(tmp, '/'))) /* we are still dired searching */
        {
                strncpy(working_tmp, tmp, c - tmp);
                working_tmp[c - tmp] = '\0';
                for (i = 0; i < strlen(c) - 1; i++)
                        tmp[i] = c[i + 1];
                tmp[i] = '\0';
                /* only a failure if we arent looking at top level */
                if (!(pino = jffs2_1pass_find_inode(pL, working_tmp, pino)) &&
                    (working_tmp[0])) {
                        putstr("find_inode failed for name=");
                        putstr(working_tmp);
                        putstr("\r\n");
                        return 0;
                }
        }

        if (tmp[0] && !(pino = jffs2_1pass_find_inode(pL, tmp, pino))) {
                putstr("find_inode failed for name=");
                putstr(tmp);
                putstr("\r\n");
                return 0;
        }
        /* this is for the bare filename, directories have already been mapped */
        if (!(pino = jffs2_1pass_list_inodes(pL, pino))) {
                putstr("find_inode failed for name=");
                putstr(tmp);
                putstr("\r\n");
                return 0;
        }
        return pino;

}

unsigned char
jffs2_1pass_rescan_needed(struct part_info *part)
{
        struct b_node *b;
        struct jffs2_unknown_node onode;
        struct jffs2_unknown_node *node;
        struct b_lists *pL = (struct b_lists *)part->jffs2_priv;

        if (part->jffs2_priv == 0){
                DEBUGF ("rescan: First time in use\n");
                return 1;
        }

        /* if we have no list, we need to rescan */
        if (pL->frag.listCount == 0) {
                DEBUGF ("rescan: fraglist zero\n");
                return 1;
        }

        /* but suppose someone reflashed a partition at the same offset... */
        b = pL->dir.listHead;
        while (b) {
                node = (struct jffs2_unknown_node *) get_fl_mem(b->offset,
                        sizeof(onode), &onode);
                if (node->nodetype != JFFS2_NODETYPE_DIRENT) {
                        DEBUGF ("rescan: fs changed beneath me? (%lx)\n",
                                        (unsigned long) b->offset);
                        return 1;
                }
                b = b->next;
        }
        return 0;
}

#ifdef CONFIG_JFFS2_SUMMARY
static u32 sum_get_unaligned32(u32 *ptr)
{
        u32 val;
        u8 *p = (u8 *)ptr;

        val = *p | (*(p + 1) << 8) | (*(p + 2) << 16) | (*(p + 3) << 24);

        return __le32_to_cpu(val);
}

static u16 sum_get_unaligned16(u16 *ptr)
{
        u16 val;
        u8 *p = (u8 *)ptr;

        val = *p | (*(p + 1) << 8);

        return __le16_to_cpu(val);
}

#define dbg_summary(...) do {} while (0);
/*
 * Process the stored summary information - helper function for
 * jffs2_sum_scan_sumnode()
 */

static int jffs2_sum_process_sum_data(struct part_info *part, uint32_t offset,
                                struct jffs2_raw_summary *summary,
                                struct b_lists *pL)
{
        void *sp;
        int i, pass;
        void *ret;

        for (pass = 0; pass < 2; pass++) {
                sp = summary->sum;

                for (i = 0; i < summary->sum_num; i++) {
                        struct jffs2_sum_unknown_flash *spu = sp;
                        dbg_summary("processing summary index %d\n", i);

                        switch (sum_get_unaligned16(&spu->nodetype)) {
                                case JFFS2_NODETYPE_INODE: {
                                struct jffs2_sum_inode_flash *spi;
                                        if (pass) {
                                                spi = sp;

                                                ret = insert_node(&pL->frag,
                                                        (u32)part->offset +
                                                        offset +
                                                        sum_get_unaligned32(
                                                                &spi->offset));
                                                if (ret == NULL)
                                                        return -1;
                                        }

                                        sp += JFFS2_SUMMARY_INODE_SIZE;

                                        break;
                                }
                                case JFFS2_NODETYPE_DIRENT: {
                                        struct jffs2_sum_dirent_flash *spd;
                                        spd = sp;
                                        if (pass) {
                                                ret = insert_node(&pL->dir,
                                                        (u32) part->offset +
                                                        offset +
                                                        sum_get_unaligned32(
                                                                &spd->offset));
                                                if (ret == NULL)
                                                        return -1;
                                        }

                                        sp += JFFS2_SUMMARY_DIRENT_SIZE(
                                                        spd->nsize);

                                        break;
                                }
                                default : {
                                        uint16_t nodetype = sum_get_unaligned16(
                                                                &spu->nodetype);
                                        printf("Unsupported node type %x found"
                                                        " in summary!\n",
                                                        nodetype);
                                        if ((nodetype & JFFS2_COMPAT_MASK) ==
                                                        JFFS2_FEATURE_INCOMPAT)
                                                return -EIO;
                                        return -EBADMSG;
                                }
                        }
                }
        }
        return 0;
}

/* Process the summary node - called from jffs2_scan_eraseblock() */
int jffs2_sum_scan_sumnode(struct part_info *part, uint32_t offset,
                           struct jffs2_raw_summary *summary, uint32_t sumsize,
                           struct b_lists *pL)
{
        struct jffs2_unknown_node crcnode;
        int ret, __maybe_unused ofs;
        uint32_t crc;

        ofs = part->sector_size - sumsize;

        dbg_summary("summary found for 0x%08x at 0x%08x (0x%x bytes)\n",
                    offset, offset + ofs, sumsize);

        /* OK, now check for node validity and CRC */
        crcnode.magic = JFFS2_MAGIC_BITMASK;
        crcnode.nodetype = JFFS2_NODETYPE_SUMMARY;
        crcnode.totlen = summary->totlen;
        crc = crc32_no_comp(0, (uchar *)&crcnode, sizeof(crcnode)-4);

        if (summary->hdr_crc != crc) {
                dbg_summary("Summary node header is corrupt (bad CRC or "
                                "no summary at all)\n");
                goto crc_err;
        }

        if (summary->totlen != sumsize) {
                dbg_summary("Summary node is corrupt (wrong erasesize?)\n");
                goto crc_err;
        }

        crc = crc32_no_comp(0, (uchar *)summary,
                        sizeof(struct jffs2_raw_summary)-8);

        if (summary->node_crc != crc) {
                dbg_summary("Summary node is corrupt (bad CRC)\n");
                goto crc_err;
        }

        crc = crc32_no_comp(0, (uchar *)summary->sum,
                        sumsize - sizeof(struct jffs2_raw_summary));

        if (summary->sum_crc != crc) {
                dbg_summary("Summary node data is corrupt (bad CRC)\n");
                goto crc_err;
        }

        if (summary->cln_mkr)
                dbg_summary("Summary : CLEANMARKER node \n");

        ret = jffs2_sum_process_sum_data(part, offset, summary, pL);
        if (ret == -EBADMSG)
                return 0;
        if (ret)
                return ret;             /* real error */

        return 1;

crc_err:
        putstr("Summary node crc error, skipping summary information.\n");

        return 0;
}
#endif /* CONFIG_JFFS2_SUMMARY */

#ifdef DEBUG_FRAGMENTS
static void
dump_fragments(struct b_lists *pL)
{
        struct b_node *b;
        struct jffs2_raw_inode ojNode;
        struct jffs2_raw_inode *jNode;

        putstr("\r\n\r\n******The fragment Entries******\r\n");
        b = pL->frag.listHead;
        while (b) {
                jNode = (struct jffs2_raw_inode *) get_fl_mem(b->offset,
                        sizeof(ojNode), &ojNode);
                putLabeledWord("\r\n\tbuild_list: FLASH_OFFSET = ", b->offset);
                putLabeledWord("\tbuild_list: totlen = ", jNode->totlen);
                putLabeledWord("\tbuild_list: inode = ", jNode->ino);
                putLabeledWord("\tbuild_list: version = ", jNode->version);
                putLabeledWord("\tbuild_list: isize = ", jNode->isize);
                putLabeledWord("\tbuild_list: atime = ", jNode->atime);
                putLabeledWord("\tbuild_list: offset = ", jNode->offset);
                putLabeledWord("\tbuild_list: csize = ", jNode->csize);
                putLabeledWord("\tbuild_list: dsize = ", jNode->dsize);
                putLabeledWord("\tbuild_list: compr = ", jNode->compr);
                putLabeledWord("\tbuild_list: usercompr = ", jNode->usercompr);
                putLabeledWord("\tbuild_list: flags = ", jNode->flags);
                putLabeledWord("\tbuild_list: offset = ", b->offset);   /* FIXME: ? [RS] */
                b = b->next;
        }
}
#endif

#ifdef DEBUG_DIRENTS
static void
dump_dirents(struct b_lists *pL)
{
        struct b_node *b;
        struct jffs2_raw_dirent *jDir;

        putstr("\r\n\r\n******The directory Entries******\r\n");
        b = pL->dir.listHead;
        while (b) {
                jDir = (struct jffs2_raw_dirent *) get_node_mem(b->offset,
                                                                pL->readbuf);
                putstr("\r\n");
                putnstr(jDir->name, jDir->nsize);
                putLabeledWord("\r\n\tbuild_list: magic = ", jDir->magic);
                putLabeledWord("\tbuild_list: nodetype = ", jDir->nodetype);
                putLabeledWord("\tbuild_list: hdr_crc = ", jDir->hdr_crc);
                putLabeledWord("\tbuild_list: pino = ", jDir->pino);
                putLabeledWord("\tbuild_list: version = ", jDir->version);
                putLabeledWord("\tbuild_list: ino = ", jDir->ino);
                putLabeledWord("\tbuild_list: mctime = ", jDir->mctime);
                putLabeledWord("\tbuild_list: nsize = ", jDir->nsize);
                putLabeledWord("\tbuild_list: type = ", jDir->type);
                putLabeledWord("\tbuild_list: node_crc = ", jDir->node_crc);
                putLabeledWord("\tbuild_list: name_crc = ", jDir->name_crc);
                putLabeledWord("\tbuild_list: offset = ", b->offset);   /* FIXME: ? [RS] */
                b = b->next;
                put_fl_mem(jDir, pL->readbuf);
        }
}
#endif

#define DEFAULT_EMPTY_SCAN_SIZE 256

static inline uint32_t EMPTY_SCAN_SIZE(uint32_t sector_size)
{
        if (sector_size < DEFAULT_EMPTY_SCAN_SIZE)
                return sector_size;
        else
                return DEFAULT_EMPTY_SCAN_SIZE;
}

static u32
jffs2_1pass_build_lists(struct part_info * part)
{
        struct b_lists *pL;
        struct jffs2_unknown_node *node;
        u32 nr_sectors;
        u32 i;
        u32 counter4 = 0;
        u32 counterF = 0;
        u32 counterN = 0;
        u32 max_totlen = 0;
        u32 buf_size;
        char *buf;

        nr_sectors = lldiv(part->size, part->sector_size);
        /* turn off the lcd.  Refreshing the lcd adds 50% overhead to the */
        /* jffs2 list building enterprise nope.  in newer versions the overhead is */
        /* only about 5 %.  not enough to inconvenience people for. */
        /* lcd_off(); */

        /* if we are building a list we need to refresh the cache. */
        jffs_init_1pass_list(part);
        pL = (struct b_lists *)part->jffs2_priv;
        buf = malloc(DEFAULT_EMPTY_SCAN_SIZE);
        puts ("Scanning JFFS2 FS:   ");

        /* start at the beginning of the partition */
        for (i = 0; i < nr_sectors; i++) {
                uint32_t sector_ofs = i * part->sector_size;
                uint32_t buf_ofs = sector_ofs;
                uint32_t buf_len;
                uint32_t ofs, prevofs;
#ifdef CONFIG_JFFS2_SUMMARY
                struct jffs2_sum_marker *sm;
                void *sumptr = NULL;
                uint32_t sumlen;
                int ret;
#endif
                /* Indicates a sector with a CLEANMARKER was found */
                int clean_sector = 0;

                /* Set buf_size to maximum length */
                buf_size = DEFAULT_EMPTY_SCAN_SIZE;
                WATCHDOG_RESET();

#ifdef CONFIG_JFFS2_SUMMARY
                buf_len = sizeof(*sm);

                /* Read as much as we want into the _end_ of the preallocated
                 * buffer
                 */
                get_fl_mem(part->offset + sector_ofs + part->sector_size -
                                buf_len, buf_len, buf + buf_size - buf_len);

                sm = (void *)buf + buf_size - sizeof(*sm);
                if (sm->magic == JFFS2_SUM_MAGIC) {
                        sumlen = part->sector_size - sm->offset;
                        sumptr = buf + buf_size - sumlen;

                        /* Now, make sure the summary itself is available */
                        if (sumlen > buf_size) {
                                /* Need to kmalloc for this. */
                                sumptr = malloc(sumlen);
                                if (!sumptr) {
                                        putstr("Can't get memory for summary "
                                                        "node!\n");
                                        free(buf);
                                        jffs2_free_cache(part);
                                        return 0;
                                }
                                memcpy(sumptr + sumlen - buf_len, buf +
                                                buf_size - buf_len, buf_len);
                        }
                        if (buf_len < sumlen) {
                                /* Need to read more so that the entire summary
                                 * node is present
                                 */
                                get_fl_mem(part->offset + sector_ofs +
                                                part->sector_size - sumlen,
                                                sumlen - buf_len, sumptr);
                        }
                }

                if (sumptr) {
                        ret = jffs2_sum_scan_sumnode(part, sector_ofs, sumptr,
                                        sumlen, pL);

                        if (buf_size && sumlen > buf_size)
                                free(sumptr);
                        if (ret < 0) {
                                free(buf);
                                jffs2_free_cache(part);
                                return 0;
                        }
                        if (ret)
                                continue;

                }
#endif /* CONFIG_JFFS2_SUMMARY */

                buf_len = EMPTY_SCAN_SIZE(part->sector_size);

                get_fl_mem((u32)part->offset + buf_ofs, buf_len, buf);

                /* 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(part->sector_size) &&
                                *(uint32_t *)(&buf[ofs]) == 0xFFFFFFFF)
                        ofs += 4;

                if (ofs == EMPTY_SCAN_SIZE(part->sector_size))
                        continue;

                ofs += sector_ofs;
                prevofs = ofs - 1;
                /*
                 * Set buf_size down to the minimum size required.
                 * This prevents reading in chunks of flash data unnecessarily.
                 */
                buf_size = sizeof(union jffs2_node_union);

        scan_more:
                while (ofs < sector_ofs + part->sector_size) {
                        if (ofs == prevofs) {
                                printf("offset %08x already seen, skip\n", ofs);
                                ofs += 4;
                                counter4++;
                                continue;
                        }
                        prevofs = ofs;
                        if (sector_ofs + part->sector_size <
                                        ofs + sizeof(*node))
                                break;
                        if (buf_ofs + buf_len < ofs + sizeof(*node)) {
                                buf_len = min_t(uint32_t, buf_size, sector_ofs
                                                + part->sector_size - ofs);
                                get_fl_mem((u32)part->offset + ofs, buf_len,
                                           buf);
                                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 scan_end;

                                ofs += 4;
                                scan_end = min_t(uint32_t, EMPTY_SCAN_SIZE(
                                                        part->sector_size)/8,
                                                        buf_len);
                        more_empty:
                                inbuf_ofs = ofs - buf_ofs;
                                while (inbuf_ofs < scan_end) {
                                        if (*(uint32_t *)(&buf[inbuf_ofs]) !=
                                                        0xffffffff)
                                                goto scan_more;

                                        inbuf_ofs += 4;
                                        ofs += 4;
                                }
                                /* Ran off end. */
                                /*
                                 * If this sector had a clean marker at the
                                 * beginning, and immediately following this
                                 * have been a bunch of FF bytes, treat the
                                 * entire sector as empty.
                                 */
                                if (clean_sector)
                                        break;

                                /* See how much more there is to read in this
                                 * eraseblock...
                                 */
                                buf_len = min_t(uint32_t, buf_size,
                                                sector_ofs +
                                                part->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)
                                         */
                                        break;
                                }
                                scan_end = buf_len;
                                get_fl_mem((u32)part->offset + ofs, buf_len,
                                           buf);
                                buf_ofs = ofs;
                                goto more_empty;
                        }
                        /*
                         * Found something not erased in the sector, so reset
                         * the 'clean_sector' flag.
                         */
                        clean_sector = 0;
                        if (node->magic != JFFS2_MAGIC_BITMASK ||
                                        !hdr_crc(node)) {
                                ofs += 4;
                                counter4++;
                                continue;
                        }
                        if (ofs + node->totlen >
                                        sector_ofs + part->sector_size) {
                                ofs += 4;
                                counter4++;
                                continue;
                        }
                        /* if its a fragment add it */
                        switch (node->nodetype) {
                        case JFFS2_NODETYPE_INODE:
                                if (buf_ofs + buf_len < ofs + sizeof(struct
                                                        jffs2_raw_inode)) {
                                        buf_len = min_t(uint32_t,
                                                        sizeof(struct jffs2_raw_inode),
                                                        sector_ofs +
                                                        part->sector_size -
                                                        ofs);
                                        get_fl_mem((u32)part->offset + ofs,
                                                   buf_len, buf);
                                        buf_ofs = ofs;
                                        node = (void *)buf;
                                }
                                if (!inode_crc((struct jffs2_raw_inode *)node))
                                        break;

                                if (insert_node(&pL->frag, (u32) part->offset +
                                                ofs) == NULL) {
                                        free(buf);
                                        jffs2_free_cache(part);
                                        return 0;
                                }
                                if (max_totlen < node->totlen)
                                        max_totlen = node->totlen;
                                break;
                        case JFFS2_NODETYPE_DIRENT:
                                if (buf_ofs + buf_len < ofs + sizeof(struct
                                                        jffs2_raw_dirent) +
                                                        ((struct
                                                         jffs2_raw_dirent *)
                                                        node)->nsize) {
                                        buf_len = min_t(uint32_t,
                                                        node->totlen,
                                                        sector_ofs +
                                                        part->sector_size -
                                                        ofs);
                                        get_fl_mem((u32)part->offset + ofs,
                                                   buf_len, buf);
                                        buf_ofs = ofs;
                                        node = (void *)buf;
                                }

                                if (!dirent_crc((struct jffs2_raw_dirent *)
                                                        node) ||
                                                !dirent_name_crc(
                                                        (struct
                                                         jffs2_raw_dirent *)
                                                        node))
                                        break;
                                if (! (counterN%100))
                                        puts ("\b\b.  ");
                                if (insert_node(&pL->dir, (u32) part->offset +
                                                ofs) == NULL) {
                                        free(buf);
                                        jffs2_free_cache(part);
                                        return 0;
                                }
                                if (max_totlen < node->totlen)
                                        max_totlen = node->totlen;
                                counterN++;
                                break;
                        case JFFS2_NODETYPE_CLEANMARKER:
                                if (node->totlen != sizeof(struct jffs2_unknown_node))
                                        printf("OOPS Cleanmarker has bad size "
                                                "%d != %zu\n",
                                                node->totlen,
                                                sizeof(struct jffs2_unknown_node));
                                if ((node->totlen ==
                                     sizeof(struct jffs2_unknown_node)) &&
                                    (ofs == sector_ofs)) {
                                        /*
                                         * Found a CLEANMARKER at the beginning
                                         * of the sector. It's in the correct
                                         * place with correct size and CRC.
                                         */
                                        clean_sector = 1;
                                }
                                break;
                        case JFFS2_NODETYPE_PADDING:
                                if (node->totlen < sizeof(struct jffs2_unknown_node))
                                        printf("OOPS Padding has bad size "
                                                "%d < %zu\n",
                                                node->totlen,
                                                sizeof(struct jffs2_unknown_node));
                                break;
                        case JFFS2_NODETYPE_SUMMARY:
                                break;
                        default:
                                printf("Unknown node type: %x len %d offset 0x%x\n",
                                        node->nodetype,
                                        node->totlen, ofs);
                        }
                        ofs += ((node->totlen + 3) & ~3);
                        counterF++;
                }
        }

        free(buf);
#if defined(CONFIG_SYS_JFFS2_SORT_FRAGMENTS)
        /*
         * Sort the lists.
         */
        sort_list(&pL->frag);
        sort_list(&pL->dir);
#endif
        putstr("\b\b done.\r\n");               /* close off the dots */

        /* We don't care if malloc failed - then each read operation will
         * allocate its own buffer as necessary (NAND) or will read directly
         * from flash (NOR).
         */
        pL->readbuf = malloc(max_totlen);

        /* turn the lcd back on. */
        /* splash(); */

#if 0
        putLabeledWord("dir entries = ", pL->dir.listCount);
        putLabeledWord("frag entries = ", pL->frag.listCount);
        putLabeledWord("+4 increments = ", counter4);
        putLabeledWord("+file_offset increments = ", counterF);

#endif

#ifdef DEBUG_DIRENTS
        dump_dirents(pL);
#endif

#ifdef DEBUG_FRAGMENTS
        dump_fragments(pL);
#endif

        /* give visual feedback that we are done scanning the flash */
        led_blink(0x0, 0x0, 0x1, 0x1);  /* off, forever, on 100ms, off 100ms */
        return 1;
}


static u32
jffs2_1pass_fill_info(struct b_lists * pL, struct b_jffs2_info * piL)
{
        struct b_node *b;
        struct jffs2_raw_inode ojNode;
        struct jffs2_raw_inode *jNode;
        int i;

        for (i = 0; i < JFFS2_NUM_COMPR; i++) {
                piL->compr_info[i].num_frags = 0;
                piL->compr_info[i].compr_sum = 0;
                piL->compr_info[i].decompr_sum = 0;
        }

        b = pL->frag.listHead;
        while (b) {
                jNode = (struct jffs2_raw_inode *) get_fl_mem(b->offset,
                        sizeof(ojNode), &ojNode);
                if (jNode->compr < JFFS2_NUM_COMPR) {
                        piL->compr_info[jNode->compr].num_frags++;
                        piL->compr_info[jNode->compr].compr_sum += jNode->csize;
                        piL->compr_info[jNode->compr].decompr_sum += jNode->dsize;
                }
                b = b->next;
        }
        return 0;
}


static struct b_lists *
jffs2_get_list(struct part_info * part, const char *who)
{
        /* copy requested part_info struct pointer to global location */
        current_part = part;

        if (jffs2_1pass_rescan_needed(part)) {
                if (!jffs2_1pass_build_lists(part)) {
                        printf("%s: Failed to scan JFFSv2 file structure\n", who);
                        return NULL;
                }
        }
        return (struct b_lists *)part->jffs2_priv;
}


/* Print directory / file contents */
u32
jffs2_1pass_ls(struct part_info * part, const char *fname)
{
        struct b_lists *pl;
        long ret = 1;
        u32 inode;

        if (! (pl = jffs2_get_list(part, "ls")))
                return 0;

        if (! (inode = jffs2_1pass_search_list_inodes(pl, fname, 1))) {
                putstr("ls: Failed to scan jffs2 file structure\r\n");
                return 0;
        }


#if 0
        putLabeledWord("found file at inode = ", inode);
        putLabeledWord("read_inode returns = ", ret);
#endif

        return ret;
}


/* Load a file from flash into memory. fname can be a full path */
u32
jffs2_1pass_load(char *dest, struct part_info * part, const char *fname)
{

        struct b_lists *pl;
        long ret = 1;
        u32 inode;

        if (! (pl  = jffs2_get_list(part, "load")))
                return 0;

        if (! (inode = jffs2_1pass_search_inode(pl, fname, 1))) {
                putstr("load: Failed to find inode\r\n");
                return 0;
        }

        /* Resolve symlinks */
        if (! (inode = jffs2_1pass_resolve_inode(pl, inode))) {
                putstr("load: Failed to resolve inode structure\r\n");
                return 0;
        }

        if ((ret = jffs2_1pass_read_inode(pl, inode, dest)) < 0) {
                putstr("load: Failed to read inode\r\n");
                return 0;
        }

        DEBUGF ("load: loaded '%s' to 0x%lx (%ld bytes)\n", fname,
                                (unsigned long) dest, ret);
        return ret;
}

/* Return information about the fs on this partition */
u32
jffs2_1pass_info(struct part_info * part)
{
        struct b_jffs2_info info;
        struct b_lists *pl;
        int i;

        if (! (pl  = jffs2_get_list(part, "info")))
                return 0;

        jffs2_1pass_fill_info(pl, &info);
        for (i = 0; i < JFFS2_NUM_COMPR; i++) {
                printf ("Compression: %s\n"
                        "\tfrag count: %d\n"
                        "\tcompressed sum: %d\n"
                        "\tuncompressed sum: %d\n",
                        compr_names[i],
                        info.compr_info[i].num_frags,
                        info.compr_info[i].compr_sum,
                        info.compr_info[i].decompr_sum);
        }
        return 1;
}