1 files changed, 290 insertions, 185 deletions

diff --git a/fs/jffs2/readinode.c b/fs/jffs2/readinode.c
index f3b12d7fe9ab..488787a823b6 100644
--- a/fs/jffs2/readinode.c
+++ b/fs/jffs2/readinode.c
@@ -7,7 +7,7 @@
  *
  * For licensing information, see the file 'LICENCE' in this directory.
  *
- * $Id: readinode.c,v 1.134 2005/07/31 08:20:44 dedekind Exp $
+ * $Id: readinode.c,v 1.135 2005/08/01 12:05:19 dedekind Exp $
  *
  */
 
@@ -21,8 +21,8 @@
 #include <linux/compiler.h>
 #include "nodelist.h"
 
-/* 
- * Put a new tmp_dnode_info into the temporaty RB-tree, keeping the list in 
+/*
+ * Put a new tmp_dnode_info into the temporaty RB-tree, keeping the list in
  * order of increasing version.
  */
 static void jffs2_add_tn_to_tree(struct jffs2_tmp_dnode_info *tn, struct rb_root *list)
@@ -38,11 +38,11 @@ static void jffs2_add_tn_to_tree(struct jffs2_tmp_dnode_info *tn, struct rb_root
                 /* There may actually be a collision here, but it doesn't
                    actually matter. As long as the two nodes with the same
                    version are together, it's all fine. */
-                if (tn->version < this->version)
+                if (tn->version > this->version)
                         p = &(*p)->rb_left;
                 else
                         p = &(*p)->rb_right;
-        }
+        }
 
         rb_link_node(&tn->rb, parent, p);
         rb_insert_color(&tn->rb, list);
@@ -111,14 +111,9 @@ static struct jffs2_raw_node_ref *jffs2_first_valid_node(struct jffs2_raw_node_r
  *          1 if the node should be marked obsolete;
  *          negative error code on failure.
  */
-static inline int
-read_direntry(struct jffs2_sb_info *c,
-              struct jffs2_raw_node_ref *ref,
-              struct jffs2_raw_dirent *rd,
-              uint32_t read,
-              struct jffs2_full_dirent **fdp,
-              int32_t *latest_mctime,
-              uint32_t *mctime_ver)
+static inline int read_direntry(struct jffs2_sb_info *c, struct jffs2_raw_node_ref *ref,
+                                struct jffs2_raw_dirent *rd, uint32_t read, struct jffs2_full_dirent **fdp,
+                                uint32_t *latest_mctime, uint32_t *mctime_ver)
 {
         struct jffs2_full_dirent *fd;
         
@@ -196,30 +191,35 @@ read_direntry(struct jffs2_sb_info *c,
  *          1 if the node should be marked obsolete;
  *          negative error code on failure.
  */
-static inline int
-read_dnode(struct jffs2_sb_info *c,
-           struct jffs2_raw_node_ref *ref,
-           struct jffs2_raw_inode *rd,
-           uint32_t read,
-           struct rb_root *tnp,
-           int32_t *latest_mctime,
-           uint32_t *mctime_ver)
+static inline int read_dnode(struct jffs2_sb_info *c, struct jffs2_raw_node_ref *ref,
+                             struct jffs2_raw_inode *rd, struct rb_root *tnp, int rdlen,
+                             uint32_t *latest_mctime, uint32_t *mctime_ver)
 {
-        struct jffs2_eraseblock *jeb;
         struct jffs2_tmp_dnode_info *tn;
+        uint32_t len, csize;
+        int ret = 1;
         
         /* Obsoleted. This cannot happen, surely? dwmw2 20020308 */
         BUG_ON(ref_obsolete(ref));
 
+        tn = jffs2_alloc_tmp_dnode_info();
+        if (!tn) {
+                JFFS2_ERROR("failed to allocate tn (%d bytes).\n", sizeof(*tn));
+                return -ENOMEM;
+        }
+
+        tn->partial_crc = 0;
+        csize = je32_to_cpu(rd->csize);
+        
         /* If we've never checked the CRCs on this node, check them now */
         if (ref_flags(ref) == REF_UNCHECKED) {
-                uint32_t crc, len;
+                uint32_t crc;
 
                 crc = crc32(0, rd, sizeof(*rd) - 8);
                 if (unlikely(crc != je32_to_cpu(rd->node_crc))) {
                         JFFS2_NOTICE("header CRC failed on node at %#08x: read %#08x, calculated %#08x\n",
                                         ref_offset(ref), je32_to_cpu(rd->node_crc), crc);
-                        return 1;
+                        goto free_out;
                 }
                 
                 /* Sanity checks */
@@ -227,107 +227,102 @@ read_dnode(struct jffs2_sb_info *c,
                     unlikely(PAD(je32_to_cpu(rd->csize) + sizeof(*rd)) != PAD(je32_to_cpu(rd->totlen)))) {
                                 JFFS2_WARNING("inode node header CRC is corrupted at %#08x\n", ref_offset(ref));
                                 jffs2_dbg_dump_node(c, ref_offset(ref));
-                        return 1;
+                        goto free_out;
                 }
 
-                if (rd->compr != JFFS2_COMPR_ZERO && je32_to_cpu(rd->csize)) {
-                        unsigned char *buf = NULL;
-                        uint32_t pointed = 0;
-                        int err;
-#ifndef __ECOS
-                        if (c->mtd->point) {
-                                err = c->mtd->point (c->mtd, ref_offset(ref) + sizeof(*rd), je32_to_cpu(rd->csize),
-                                                     &read, &buf);
-                                if (unlikely(read < je32_to_cpu(rd->csize)) && likely(!err)) {
-                                        JFFS2_ERROR("MTD point returned len too short: 0x%zx\n", read);
-                                        c->mtd->unpoint(c->mtd, buf, ref_offset(ref) + sizeof(*rd),
-                                                        je32_to_cpu(rd->csize));
-                                } else if (unlikely(err)){
-                                        JFFS2_ERROR("MTD point failed %d\n", err);
-                                } else
-                                        pointed = 1; /* succefully pointed to device */
-                        }
-#endif                                  
-                        if(!pointed){
-                                buf = kmalloc(je32_to_cpu(rd->csize), GFP_KERNEL);
-                                if (!buf)
-                                        return -ENOMEM;
-                                
-                                err = jffs2_flash_read(c, ref_offset(ref) + sizeof(*rd), je32_to_cpu(rd->csize),
-                                                        &read, buf);
-                                if (unlikely(read != je32_to_cpu(rd->csize)) && likely(!err))
-                                        err = -EIO;
-                                if (err) {
-                                        kfree(buf);
-                                        return err;
-                                }
-                        }
-                        crc = crc32(0, buf, je32_to_cpu(rd->csize));
-                        if(!pointed)
-                                kfree(buf);
-#ifndef __ECOS
-                        else
-                                c->mtd->unpoint(c->mtd, buf, ref_offset(ref) + sizeof(*rd), je32_to_cpu(rd->csize));
-#endif
-
-                        if (crc != je32_to_cpu(rd->data_crc)) {
-                                JFFS2_NOTICE("data CRC failed on node at %#08x: read %#08x, calculated %#08x\n",
-                                        ref_offset(ref), je32_to_cpu(rd->data_crc), crc);
-                                return 1;
-                        }
+                if (jffs2_is_writebuffered(c) && csize != 0) {
+                        /* At this point we are supposed to check the data CRC
+                         * of our unchecked node. But thus far, we do not
+                         * know whether the node is valid or obsolete. To
+                         * figure this out, we need to walk all the nodes of
+                         * the inode and build the inode fragtree. We don't
+                         * want to spend time checking data of nodes which may
+                         * later be found to be obsolete. So we put off the full
+                         * data CRC checking until we have read all the inode
+                         * nodes and have started building the fragtree.
+                         *
+                         * The fragtree is being built starting with nodes
+                         * having the highest version number, so we'll be able
+                         * to detect whether a node is valid (i.e., it is not
+                         * overlapped by a node with higher version) or not.
+                         * And we'll be able to check only those nodes, which
+                         * are not obsolete.
+                         *
+                         * Of course, this optimization only makes sense in case
+                         * of NAND flashes (or other flashes whith
+                         * !jffs2_can_mark_obsolete()), since on NOR flashes
+                         * nodes are marked obsolete physically.
+                         *
+                         * Since NAND flashes (or other flashes with
+                         * jffs2_is_writebuffered(c)) are anyway read by
+                         * fractions of c->wbuf_pagesize, and we have just read
+                         * the node header, it is likely that the starting part
+                         * of the node data is also read when we read the
+                         * header. So we don't mind to check the CRC of the
+                         * starting part of the data of the node now, and check
+                         * the second part later (in jffs2_check_node_data()).
+                         * Of course, we will not need to re-read and re-check
+                         * the NAND page which we have just read. This is why we
+                         * read the whole NAND page at jffs2_get_inode_nodes(),
+                         * while we needed only the node header.
+                         */
+                        unsigned char *buf;
+
+                        /* 'buf' will point to the start of data */
+                        buf = (unsigned char *)rd + sizeof(*rd);
+                        /* len will be the read data length */
+                        len = min_t(uint32_t, rdlen - sizeof(*rd), csize);
                         
-                }
-
-                /* Mark the node as having been checked and fix the accounting accordingly */
-                jeb = &c->blocks[ref->flash_offset / c->sector_size];
-                len = ref_totlen(c, jeb, ref);
-
-                spin_lock(&c->erase_completion_lock);
-                jeb->used_size += len;
-                jeb->unchecked_size -= len;
-                c->used_size += len;
-                c->unchecked_size -= len;
-
-                /* If node covers at least a whole page, or if it starts at the 
-                   beginning of a page and runs to the end of the file, or if 
-                   it's a hole node, mark it REF_PRISTINE, else REF_NORMAL. 
+                        if (len)
+                                tn->partial_crc = crc = crc32(0, buf, len);
+
+                        /* If we actually calculated the whole data CRC
+                         * and it is wrong, drop the node. */
+                        if (unlikely(tn->partial_crc
+                                        != je32_to_cpu(rd->data_crc)) &&
+                                len == csize)
+                                goto free_out;
 
-                   If it's actually overlapped, it'll get made NORMAL (or OBSOLETE) 
-                   when the overlapping node(s) get added to the tree anyway. 
-                */
-                if ((je32_to_cpu(rd->dsize) >= PAGE_CACHE_SIZE) ||
-                    ( ((je32_to_cpu(rd->offset) & (PAGE_CACHE_SIZE-1))==0) &&
-                      (je32_to_cpu(rd->dsize) + je32_to_cpu(rd->offset) == je32_to_cpu(rd->isize)))) {
-                        JFFS2_DBG_READINODE("marking node at %#08x REF_PRISTINE\n", ref_offset(ref));
-                        ref->flash_offset = ref_offset(ref) | REF_PRISTINE;
-                } else {
-                        JFFS2_DBG_READINODE("marking node at %#08x REF_NORMAL\n", ref_offset(ref));
+                } else if (csize == 0) {
+                        /*
+                         * We checked the header CRC. If the node has no data, adjust
+                         * the space accounting now. For other nodes this will be done
+                         * later either when the node is marked obsolete or when its
+                         * data is checked.
+                         */
+                        struct jffs2_eraseblock *jeb;
+
+                        JFFS2_DBG_READINODE("the node has no data.\n");
+                        jeb = &c->blocks[ref->flash_offset / c->sector_size];
+                        len = ref_totlen(c, jeb, ref);
+
+                        spin_lock(&c->erase_completion_lock);
+                        jeb->used_size += len;
+                        jeb->unchecked_size -= len;
+                        c->used_size += len;
+                        c->unchecked_size -= len;
                         ref->flash_offset = ref_offset(ref) | REF_NORMAL;
+                        spin_unlock(&c->erase_completion_lock);
                 }
-                spin_unlock(&c->erase_completion_lock);
-        }
-
-        tn = jffs2_alloc_tmp_dnode_info();
-        if (!tn) {
-                JFFS2_ERROR("alloc tn failed\n");
-                return -ENOMEM;
         }
 
         tn->fn = jffs2_alloc_full_dnode();
         if (!tn->fn) {
                 JFFS2_ERROR("alloc fn failed\n");
-                jffs2_free_tmp_dnode_info(tn);
-                return -ENOMEM;
+                ret = -ENOMEM;
+                goto free_out;
         }
         
         tn->version = je32_to_cpu(rd->version);
         tn->fn->ofs = je32_to_cpu(rd->offset);
+        tn->data_crc = je32_to_cpu(rd->data_crc);
+        tn->csize = csize;
         tn->fn->raw = ref;
         
         /* There was a bug where we wrote hole nodes out with
            csize/dsize swapped. Deal with it */
-        if (rd->compr == JFFS2_COMPR_ZERO && !je32_to_cpu(rd->dsize) && je32_to_cpu(rd->csize))
-                tn->fn->size = je32_to_cpu(rd->csize);
+        if (rd->compr == JFFS2_COMPR_ZERO && !je32_to_cpu(rd->dsize) && csize)
+                tn->fn->size = csize;
         else // normal case...
                 tn->fn->size = je32_to_cpu(rd->dsize);
 
@@ -337,6 +332,10 @@ read_dnode(struct jffs2_sb_info *c,
         jffs2_add_tn_to_tree(tn, tnp);
 
         return 0;
+
+free_out:
+        jffs2_free_tmp_dnode_info(tn);
+        return ret;
 }
 
 /*
@@ -347,11 +346,7 @@ read_dnode(struct jffs2_sb_info *c,
  *          1 if the node should be marked obsolete;
  *          negative error code on failure.
  */
-static inline int
-read_unknown(struct jffs2_sb_info *c,
-             struct jffs2_raw_node_ref *ref,
-             struct jffs2_unknown_node *un,
-             uint32_t read)
+static inline int read_unknown(struct jffs2_sb_info *c, struct jffs2_raw_node_ref *ref, struct jffs2_unknown_node *un)
 {
         /* We don't mark unknown nodes as REF_UNCHECKED */
         BUG_ON(ref_flags(ref) == REF_UNCHECKED);
@@ -394,9 +389,62 @@ read_unknown(struct jffs2_sb_info *c,
         return 0;
 }
 
+/*
+ * Helper function for jffs2_get_inode_nodes().
+ * The function detects whether more data should be read and reads it if yes.
+ *
+ * Returns: 0 on succes;
+ *          negative error code on failure.
+ */
+static int read_more(struct jffs2_sb_info *c, struct jffs2_raw_node_ref *ref,
+                     int right_size, int *rdlen, unsigned char *buf, unsigned char *bufstart)
+{
+        int right_len, err, len;
+        size_t retlen;
+        uint32_t offs;
+
+        if (jffs2_is_writebuffered(c)) {
+                right_len = c->wbuf_pagesize - (bufstart - buf);
+                if (right_size + (int)(bufstart - buf) > c->wbuf_pagesize)
+                        right_len += c->wbuf_pagesize;
+        } else
+                right_len = right_size;
+
+        if (*rdlen == right_len)
+                return 0;
+
+        /* We need to read more data */
+        offs = ref_offset(ref) + *rdlen;
+        if (jffs2_is_writebuffered(c)) {
+                bufstart = buf + c->wbuf_pagesize;
+                len = c->wbuf_pagesize;
+        } else {
+                bufstart = buf + *rdlen;
+                len = right_size - *rdlen;
+        }
+        
+        JFFS2_DBG_READINODE("read more %d bytes.", len);
+
+        err = jffs2_flash_read(c, offs, len, &retlen, bufstart);
+        if (err) {
+                JFFS2_ERROR("can not read %d bytes from 0x%08x, "
+                        "error code: %d.\n", len, offs, err);
+                return err;
+        }
+        
+        if (retlen < len) {
+                JFFS2_ERROR("short read at %#08x: %d instead of %d.\n",
+                                offs, retlen, len);
+                return -EIO;
+        }
+
+        *rdlen = right_len;
+
+        return 0;
+}
+
 /* Get tmp_dnode_info and full_dirent for all non-obsolete nodes associated
    with this ino, returning the former in order of version */
-
 static int jffs2_get_inode_nodes(struct jffs2_sb_info *c, struct jffs2_inode_info *f,
                                  struct rb_root *tnp, struct jffs2_full_dirent **fdp,
                                  uint32_t *highest_version, uint32_t *latest_mctime,
@@ -405,22 +453,47 @@ static int jffs2_get_inode_nodes(struct jffs2_sb_info *c, struct jffs2_inode_inf
         struct jffs2_raw_node_ref *ref, *valid_ref;
         struct rb_root ret_tn = RB_ROOT;
         struct jffs2_full_dirent *ret_fd = NULL;
-        union jffs2_node_union node;
+        unsigned char *buf = NULL;
+        union jffs2_node_union *node;
         size_t retlen;
-        int err;
+        int len, err;
 
         *mctime_ver = 0;
         
         JFFS2_DBG_READINODE("ino #%u\n", f->inocache->ino);
 
-        spin_lock(&c->erase_completion_lock);
+        if (jffs2_is_writebuffered(c)) {
+                /*
+                 * If we have the write buffer, we assume the minimal I/O unit
+                 * is c->wbuf_pagesize. We implement some optimizations which in
+                 * this case and we need a temporary buffer of size =
+                 * 2*c->wbuf_pagesize bytes (see comments in read_dnode()).
+                 * Basically, we want to read not only the node header, but the
+                 * whole wbuf (NAND page in case of NAND) or 2, if the node
+                 * header overlaps the border between the 2 wbufs.
+                 */
+                len = 2*c->wbuf_pagesize;
+        } else {
+                /*
+                 * When there is no write buffer, the size of the temporary
+                 * buffer is the size of the larges node header.
+                 */
+                len = sizeof(union jffs2_node_union);
+        }
 
+        /* FIXME: in case of NOR and available ->point() this
+         * needs to be fixed. */
+        buf = kmalloc(len, GFP_KERNEL);
+        if (!buf)
+                return -ENOMEM;
+                        
+        spin_lock(&c->erase_completion_lock);
         valid_ref = jffs2_first_valid_node(f->inocache->nodes);
-
-        if (!valid_ref && (f->inocache->ino != 1))
-                JFFS2_WARNING("no valid nodes for ino #%u\n", f->inocache->ino);
-
+        if (!valid_ref && f->inocache->ino != 1)
+                JFFS2_WARNING("Eep. No valid nodes for ino #%u.\n", f->inocache->ino);
         while (valid_ref) {
+                unsigned char *bufstart;
+
                 /* We can hold a pointer to a non-obsolete node without the spinlock,
                    but _obsolete_ nodes may disappear at any time, if the block
                    they're in gets erased. So if we mark 'ref' obsolete while we're
@@ -433,70 +506,100 @@ static int jffs2_get_inode_nodes(struct jffs2_sb_info *c, struct jffs2_inode_inf
 
                 cond_resched();
 
+                /*
+                 * At this point we don't know the type of the node we're going
+                 * to read, so we do not know the size of its header. In order
+                 * to minimize the amount of flash IO we assume the node has
+                 * size = JFFS2_MIN_NODE_HEADER.
+                 */
+                if (jffs2_is_writebuffered(c)) {
+                        /* 
+                         * We treat 'buf' as 2 adjacent wbufs. We want to
+                         * adjust bufstart such as it points to the
+                         * beginning of the node within this wbuf.
+                         */
+                        bufstart = buf + (ref_offset(ref) % c->wbuf_pagesize);
+                        /* We will read either one wbuf or 2 wbufs. */
+                        len = c->wbuf_pagesize - (bufstart - buf);
+                        if (JFFS2_MIN_NODE_HEADER +
+                                (int)(bufstart - buf) > c->wbuf_pagesize) {
+                                /* The header spans the border of the
+                                 * first wbuf */
+                                len += c->wbuf_pagesize;
+                        }
+                } else {
+                        bufstart = buf;
+                        len = JFFS2_MIN_NODE_HEADER;
+                }
+
+                JFFS2_DBG_READINODE("read %d bytes at %#08x(%d).\n", len, ref_offset(ref), ref_flags(ref));
+
                 /* FIXME: point() */
-                err = jffs2_flash_read(c, (ref_offset(ref)), 
-                                       min_t(uint32_t, ref_totlen(c, NULL, ref), sizeof(node)),
-                                       &retlen, (void *)&node);
+                err = jffs2_flash_read(c, ref_offset(ref), len,
+                                       &retlen, bufstart);
                 if (err) {
-                        JFFS2_ERROR("error %d reading node at 0x%08x in get_inode_nodes()\n", err, ref_offset(ref));
+                        JFFS2_ERROR("can not read %d bytes from 0x%08x, " "error code: %d.\n", len, ref_offset(ref), err);
+                        goto free_out;
+                }
+                
+                if (retlen < len) {
+                        JFFS2_ERROR("short read at %#08x: %d instead of %d.\n", ref_offset(ref), retlen, len);
+                        err = -EIO;
                         goto free_out;
                 }
+                
+                node = (union jffs2_node_union *)bufstart;
                         
-                switch (je16_to_cpu(node.u.nodetype)) {
+                switch (je16_to_cpu(node->u.nodetype)) {
                         
                 case JFFS2_NODETYPE_DIRENT:
-                        JFFS2_DBG_READINODE("node at %08x (%d) is a dirent node\n", ref_offset(ref), ref_flags(ref));
-                        
-                        if (retlen < sizeof(node.d)) {
-                                JFFS2_ERROR("short read dirent at %#08x\n", ref_offset(ref));
-                                err = -EIO;
-                                goto free_out;
-                        }
 
-                        err = read_direntry(c, ref, &node.d, retlen, &ret_fd, latest_mctime, mctime_ver);
+                        if (JFFS2_MIN_NODE_HEADER < sizeof(struct jffs2_raw_dirent)) {
+                                err = read_more(c, ref, sizeof(struct jffs2_raw_dirent), &len, buf, bufstart);
+                                if (unlikely(err))
+                                        goto free_out;
+                        }
+                        
+                        err = read_direntry(c, ref, &node->d, retlen, &ret_fd, latest_mctime, mctime_ver);
                         if (err == 1) {
                                 jffs2_mark_node_obsolete(c, ref);
                                 break;
                         } else if (unlikely(err))
                                 goto free_out;
                         
-                        if (je32_to_cpu(node.d.version) > *highest_version)
-                                *highest_version = je32_to_cpu(node.d.version);
+                        if (je32_to_cpu(node->d.version) > *highest_version)
+                                *highest_version = je32_to_cpu(node->d.version);
 
                         break;
 
                 case JFFS2_NODETYPE_INODE:
-                        JFFS2_DBG_READINODE("node at %08x (%d) is a data node\n", ref_offset(ref), ref_flags(ref));
                         
-                        if (retlen < sizeof(node.i)) {
-                                JFFS2_ERROR("short read dnode at %#08x\n", ref_offset(ref));
-                                err = -EIO;
-                                goto free_out;
+                        if (JFFS2_MIN_NODE_HEADER < sizeof(struct jffs2_raw_inode)) {
+                                err = read_more(c, ref, sizeof(struct jffs2_raw_inode), &len, buf, bufstart);
+                                if (unlikely(err))
+                                        goto free_out;
                         }
 
-                        err = read_dnode(c, ref, &node.i, retlen, &ret_tn, latest_mctime, mctime_ver);
+                        err = read_dnode(c, ref, &node->i, &ret_tn, len, latest_mctime, mctime_ver);
                         if (err == 1) {
                                 jffs2_mark_node_obsolete(c, ref);
                                 break;
                         } else if (unlikely(err))
                                 goto free_out;
 
-                        if (je32_to_cpu(node.i.version) > *highest_version)
-                                *highest_version = je32_to_cpu(node.i.version);
+                        if (je32_to_cpu(node->i.version) > *highest_version)
+                                *highest_version = je32_to_cpu(node->i.version);
                         
-                        JFFS2_DBG_READINODE("version %d, highest_version now %d\n",
-                                        je32_to_cpu(node.i.version), *highest_version);
-
                         break;
 
                 default:
-                        /* Check we've managed to read at least the common node header */
-                        if (retlen < sizeof(struct jffs2_unknown_node)) {
-                                JFFS2_ERROR("short read unknown node at %#08x\n", ref_offset(ref));
-                                return -EIO;
+                        if (JFFS2_MIN_NODE_HEADER < sizeof(struct jffs2_unknown_node)) {
+                                err = read_more(c, ref, sizeof(struct jffs2_unknown_node), &len, buf, bufstart);
+                                if (unlikely(err))
+                                        goto free_out;
                         }
-
-                        err = read_unknown(c, ref, &node.u, retlen);
+                        
+                        err = read_unknown(c, ref, &node->u);
                         if (err == 1) {
                                 jffs2_mark_node_obsolete(c, ref);
                                 break;
@@ -505,17 +608,21 @@ static int jffs2_get_inode_nodes(struct jffs2_sb_info *c, struct jffs2_inode_inf
 
                 }
                 spin_lock(&c->erase_completion_lock);
-
         }
+
         spin_unlock(&c->erase_completion_lock);
         *tnp = ret_tn;
         *fdp = ret_fd;
+        kfree(buf);
 
+        JFFS2_DBG_READINODE("nodes of inode #%u were read, the highest version is %u, latest_mctime %u, mctime_ver %u.\n",
+                        f->inocache->ino, *highest_version, *latest_mctime, *mctime_ver);
         return 0;
 
  free_out:
         jffs2_free_tmp_dnode_info_list(&ret_tn);
         jffs2_free_full_dirent_list(ret_fd);
+        kfree(buf);
         return err;
 }
 
@@ -523,14 +630,13 @@ static int jffs2_do_read_inode_internal(struct jffs2_sb_info *c,
                                         struct jffs2_inode_info *f,
                                         struct jffs2_raw_inode *latest_node)
 {
-        struct jffs2_tmp_dnode_info *tn = NULL;
+        struct jffs2_tmp_dnode_info *tn;
         struct rb_root tn_list;
         struct rb_node *rb, *repl_rb;
         struct jffs2_full_dirent *fd_list;
-        struct jffs2_full_dnode *fn = NULL;
+        struct jffs2_full_dnode *fn, *first_fn = NULL;
         uint32_t crc;
         uint32_t latest_mctime, mctime_ver;
-        uint32_t mdata_ver = 0;
         size_t retlen;
         int ret;
 
@@ -550,42 +656,33 @@ static int jffs2_do_read_inode_internal(struct jffs2_sb_info *c,
         rb = rb_first(&tn_list);
 
         while (rb) {
+                cond_resched();
                 tn = rb_entry(rb, struct jffs2_tmp_dnode_info, rb);
                 fn = tn->fn;
-
-                if (f->metadata) {
-                        if (likely(tn->version >= mdata_ver)) {
-                                JFFS2_DBG_READINODE("obsoleting old metadata at 0x%08x\n", ref_offset(f->metadata->raw));
-                                jffs2_mark_node_obsolete(c, f->metadata->raw);
-                                jffs2_free_full_dnode(f->metadata);
-                                f->metadata = NULL;
-                                
-                                mdata_ver = 0;
-                        } else {
-                                /* This should never happen. */
-                                JFFS2_ERROR("Er. New metadata at 0x%08x with ver %d is actually older than previous ver %d at 0x%08x\n",
-                                          ref_offset(fn->raw), tn->version, mdata_ver, ref_offset(f->metadata->raw));
-                                jffs2_mark_node_obsolete(c, fn->raw);
-                                jffs2_free_full_dnode(fn);
-                                /* Fill in latest_node from the metadata, not this one we're about to free... */
-                                fn = f->metadata;
-                                goto next_tn;
-                        }
-                }
+                ret = 1;
+                JFFS2_DBG_READINODE("consider node ver %u, phys offset "
+                        "%#08x(%d), range %u-%u.\n", tn->version,
+                        ref_offset(fn->raw), ref_flags(fn->raw),
+                        fn->ofs, fn->ofs + fn->size);
 
                 if (fn->size) {
-                        jffs2_add_full_dnode_to_inode(c, f, fn);
-                } else {
-                        /* Zero-sized node at end of version list. Just a metadata update */
-                        JFFS2_DBG_READINODE("metadata @%08x: ver %d\n", ref_offset(fn->raw), tn->version);
+                        ret = jffs2_add_older_frag_to_fragtree(c, f, tn);
+                        /* TODO: the error code isn't checked, check it */
+                        jffs2_dbg_fragtree_paranoia_check_nolock(f);
+                        BUG_ON(ret < 0);
+                        if (!first_fn && ret == 0)
+                                first_fn = fn;
+                } else if (!first_fn) {
+                        first_fn = fn;
                         f->metadata = fn;
-                        mdata_ver = tn->version;
-                }
-        next_tn:
+                        ret = 0; /* Prevent freeing the metadata update node */
+                } else
+                        jffs2_mark_node_obsolete(c, fn->raw);
+                        
                 BUG_ON(rb->rb_left);
                 if (rb->rb_parent && rb->rb_parent->rb_left == rb) {
                         /* We were then left-hand child of our parent. We need
-                           to move our own right-hand child into our place. */
+                         * to move our own right-hand child into our place. */
                         repl_rb = rb->rb_right;
                         if (repl_rb)
                                 repl_rb->rb_parent = rb->rb_parent;
@@ -595,7 +692,7 @@ static int jffs2_do_read_inode_internal(struct jffs2_sb_info *c,
                 rb = rb_next(rb);
 
                 /* Remove the spent tn from the tree; don't bother rebalancing
-                   but put our right-hand child in our own place. */
+                 * but put our right-hand child in our own place. */
                 if (tn->rb.rb_parent) {
                         if (tn->rb.rb_parent->rb_left == &tn->rb)
                                 tn->rb.rb_parent->rb_left = repl_rb;
@@ -606,10 +703,18 @@ static int jffs2_do_read_inode_internal(struct jffs2_sb_info *c,
                         tn->rb.rb_right->rb_parent = NULL;
 
                 jffs2_free_tmp_dnode_info(tn);
+                if (ret) {
+                        JFFS2_DBG_READINODE("delete dnode %u-%u.\n",
+                                fn->ofs, fn->ofs + fn->size);
+                        jffs2_free_full_dnode(fn);
+                }
         }
         jffs2_dbg_fragtree_paranoia_check_nolock(f);
 
-        if (!fn) {
+        BUG_ON(first_fn && ref_obsolete(first_fn->raw));
+
+        fn = first_fn;
+        if (unlikely(!first_fn)) {
                 /* No data nodes for this inode. */
                 if (f->inocache->ino != 1) {
                         JFFS2_WARNING("no data nodes found for ino #%u\n", f->inocache->ino);