[JFFS2] Split a large routine on several smaller.

Signed-off-by: Artem B. Bityutskiy <dedekind@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

1 files changed, 336 insertions, 261 deletions

diff --git a/fs/jffs2/nodelist.c b/fs/jffs2/nodelist.c
index 4991c348f6ec..a04111530f4d 100644
--- a/fs/jffs2/nodelist.c
+++ b/fs/jffs2/nodelist.c
@@ -7,7 +7,7 @@
  *
  * For licensing information, see the file 'LICENCE' in this directory.
  *
- * $Id: nodelist.c,v 1.98 2005/07/10 15:15:32 dedekind Exp $
+ * $Id: nodelist.c,v 1.99 2005/07/15 10:13:54 dedekind Exp $
  *
  */
 
@@ -137,6 +137,307 @@ static struct jffs2_raw_node_ref *jffs2_first_valid_node(struct jffs2_raw_node_r
         return NULL;
 }
 
+/*
+ * Helper function for jffs2_get_inode_nodes().
+ * It is called every time an directory entry node is found.
+ *
+ * Returns: 0 on succes;
+ *          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)
+{
+        struct jffs2_full_dirent *fd;
+        
+        /* The direntry nodes are checked during the flash scanning */
+        BUG_ON(ref_flags(ref) == REF_UNCHECKED);
+        /* Obsoleted. This cannot happen, surely? dwmw2 20020308 */
+        BUG_ON(ref_obsolete(ref));
+                        
+        /* Sanity check */
+        if (unlikely(PAD((rd->nsize + sizeof(*rd))) != PAD(je32_to_cpu(rd->totlen)))) {
+                printk(KERN_ERR "Error! Illegal nsize in node at %#08x: nsize %#02x, totlen %#04x\n",
+                       ref_offset(ref), rd->nsize, je32_to_cpu(rd->totlen));
+                return 1;
+        }
+        
+        fd = jffs2_alloc_full_dirent(rd->nsize + 1);
+        if (unlikely(!fd))
+                return -ENOMEM;
+
+        fd->raw = ref;
+        fd->version = je32_to_cpu(rd->version);
+        fd->ino = je32_to_cpu(rd->ino);
+        fd->type = rd->type;
+
+        /* Pick out the mctime of the latest dirent */
+        if(fd->version > *mctime_ver) {
+                *mctime_ver = fd->version;
+                *latest_mctime = je32_to_cpu(rd->mctime);
+        }
+
+        /* 
+         * Copy as much of the name as possible from the raw
+         * dirent we've already read from the flash.
+         */
+        if (read > sizeof(*rd))
+                memcpy(&fd->name[0], &rd->name[0],
+                       min_t(uint32_t, rd->nsize, (read - sizeof(*rd)) ));
+                
+        /* Do we need to copy any more of the name directly from the flash? */
+        if (rd->nsize + sizeof(*rd) > read) {
+                /* FIXME: point() */
+                int err;
+                int already = read - sizeof(*rd);
+                        
+                err = jffs2_flash_read(c, (ref_offset(ref)) + read, 
+                                rd->nsize - already, &read, &fd->name[already]);
+                if (unlikely(read != rd->nsize - already) && likely(!err))
+                        return -EIO;
+                        
+                if (unlikely(err)) {
+                        printk(KERN_WARNING "Read remainder of name in jffs2_get_inode_nodes(): error %d\n", err);
+                        jffs2_free_full_dirent(fd);
+                        return -EIO;
+                }
+        }
+        
+        fd->nhash = full_name_hash(fd->name, rd->nsize);
+        fd->next = NULL;
+        fd->name[rd->nsize] = '\0';
+        
+        /*
+         * Wheee. We now have a complete jffs2_full_dirent structure, with
+         * the name in it and everything. Link it into the list 
+         */
+        D1(printk(KERN_DEBUG "Adding fd \"%s\", ino #%u\n", fd->name, fd->ino));
+
+        jffs2_add_fd_to_list(c, fd, fdp);
+
+        return 0;
+}
+
+/*
+ * Helper function for jffs2_get_inode_nodes().
+ * It is called every time an inode node is found.
+ *
+ * Returns: 0 on succes;
+ *          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)
+{
+        struct jffs2_eraseblock *jeb;
+        struct jffs2_tmp_dnode_info *tn;
+        
+        /* Obsoleted. This cannot happen, surely? dwmw2 20020308 */
+        BUG_ON(ref_obsolete(ref));
+
+        /* If we've never checked the CRCs on this node, check them now */
+        if (ref_flags(ref) == REF_UNCHECKED) {
+                uint32_t crc, len;
+
+                crc = crc32(0, rd, sizeof(*rd) - 8);
+                if (unlikely(crc != je32_to_cpu(rd->node_crc))) {
+                        printk(KERN_WARNING "Header CRC failed on node at %#08x: read %#08x, calculated %#08x\n",
+                                        ref_offset(ref), je32_to_cpu(rd->node_crc), crc);
+                        return 1;
+                }
+                
+                /* Sanity checks */
+                if (unlikely(je32_to_cpu(rd->offset) > je32_to_cpu(rd->isize)) ||
+                    unlikely(PAD(je32_to_cpu(rd->csize) + sizeof(*rd)) != PAD(je32_to_cpu(rd->totlen)))) {
+                        printk(KERN_WARNING "Inode corrupted at %#08x, totlen %d, #ino  %d, version %d, "
+                                "isize %d, csize %d, dsize %d \n",
+                                ref_offset(ref),  je32_to_cpu(rd->totlen),  je32_to_cpu(rd->ino),
+                                je32_to_cpu(rd->version),  je32_to_cpu(rd->isize), 
+                                je32_to_cpu(rd->csize), je32_to_cpu(rd->dsize));
+                        return 1;
+                }
+
+                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)) {
+                                        D1(printk(KERN_DEBUG "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)){
+                                        D1(printk(KERN_DEBUG "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)) {
+                                printk(KERN_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;
+                        }
+                        
+                }
+
+                /* 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 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)))) {
+                        D1(printk(KERN_DEBUG "Marking node at %#08x REF_PRISTINE\n", ref_offset(ref)));
+                        ref->flash_offset = ref_offset(ref) | REF_PRISTINE;
+                } else {
+                        D1(printk(KERN_DEBUG "Marking node at %#08x REF_NORMAL\n", ref_offset(ref)));
+                        ref->flash_offset = ref_offset(ref) | REF_NORMAL;
+                }
+                spin_unlock(&c->erase_completion_lock);
+        }
+
+        tn = jffs2_alloc_tmp_dnode_info();
+        if (!tn) {
+                D1(printk(KERN_DEBUG "alloc tn failed\n"));
+                return -ENOMEM;
+        }
+
+        tn->fn = jffs2_alloc_full_dnode();
+        if (!tn->fn) {
+                D1(printk(KERN_DEBUG "alloc fn failed\n"));
+                jffs2_free_tmp_dnode_info(tn);
+                return -ENOMEM;
+        }
+        
+        tn->version = je32_to_cpu(rd->version);
+        tn->fn->ofs = je32_to_cpu(rd->offset);
+        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);
+        else // normal case...
+                tn->fn->size = je32_to_cpu(rd->dsize);
+
+        D1(printk(KERN_DEBUG "dnode @%08x: ver %u, offset %#04x, dsize %#04x\n",
+                  ref_offset(ref), je32_to_cpu(rd->version),
+                  je32_to_cpu(rd->offset), je32_to_cpu(rd->dsize)));
+        
+        jffs2_add_tn_to_tree(tn, tnp);
+
+        return 0;
+}
+
+/*
+ * Helper function for jffs2_get_inode_nodes().
+ * It is called every time an unknown node is found.
+ *
+ * Returns: 0 on succes;
+ *          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)
+{
+        /* We don't mark unknown nodes as REF_UNCHECKED */
+        BUG_ON(ref_flags(ref) == REF_UNCHECKED);
+        
+        un->nodetype = cpu_to_je16(JFFS2_NODE_ACCURATE | je16_to_cpu(un->nodetype));
+
+        if (crc32(0, un, sizeof(struct jffs2_unknown_node) - 4) != je32_to_cpu(un->hdr_crc)) {
+
+                /* Hmmm. This should have been caught at scan time. */
+                printk(KERN_WARNING "Warning! Node header CRC failed at %#08x. "
+                                "But it must have been OK earlier.\n", ref_offset(ref));
+                D1(printk(KERN_DEBUG "Node was: { %#04x, %#04x, %#08x, %#08x }\n", 
+                        je16_to_cpu(un->magic), je16_to_cpu(un->nodetype),
+                        je32_to_cpu(un->totlen), je32_to_cpu(un->hdr_crc)));
+                return 1;
+        } else {
+                switch(je16_to_cpu(un->nodetype) & JFFS2_COMPAT_MASK) {
+
+                case JFFS2_FEATURE_INCOMPAT:
+                        printk(KERN_NOTICE "Unknown INCOMPAT nodetype %#04X at %#08x\n",
+                                        je16_to_cpu(un->nodetype), ref_offset(ref));
+                        /* EEP */
+                        BUG();
+                        break;
+
+                case JFFS2_FEATURE_ROCOMPAT:
+                        printk(KERN_NOTICE "Unknown ROCOMPAT nodetype %#04X at %#08x\n",
+                                        je16_to_cpu(un->nodetype), ref_offset(ref));
+                        BUG_ON(!(c->flags & JFFS2_SB_FLAG_RO));
+                        break;
+
+                case JFFS2_FEATURE_RWCOMPAT_COPY:
+                        printk(KERN_NOTICE "Unknown RWCOMPAT_COPY nodetype %#04X at %#08x\n",
+                                        je16_to_cpu(un->nodetype), ref_offset(ref));
+                        break;
+
+                case JFFS2_FEATURE_RWCOMPAT_DELETE:
+                        printk(KERN_NOTICE "Unknown RWCOMPAT_DELETE nodetype %#04X at %#08x\n",
+                                        je16_to_cpu(un->nodetype), ref_offset(ref));
+                        return 1;
+                }
+        }
+
+        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 */
 
@@ -146,9 +447,8 @@ int jffs2_get_inode_nodes(struct jffs2_sb_info *c, struct jffs2_inode_info *f,
                           uint32_t *mctime_ver)
 {
         struct jffs2_raw_node_ref *ref, *valid_ref;
-        struct jffs2_tmp_dnode_info *tn;
         struct rb_root ret_tn = RB_ROOT;
-        struct jffs2_full_dirent *fd, *ret_fd = NULL;
+        struct jffs2_full_dirent *ret_fd = NULL;
         union jffs2_node_union node;
         size_t retlen;
         int err;
@@ -186,292 +486,67 @@ int jffs2_get_inode_nodes(struct jffs2_sb_info *c, struct jffs2_inode_info *f,
                         goto free_out;
                 }
                         
-
-                        /* Check we've managed to read at least the common node header */
-                if (retlen < min_t(uint32_t, ref_totlen(c, NULL, ref), sizeof(node.u))) {
-                        printk(KERN_WARNING "short read in get_inode_nodes()\n");
-                        err = -EIO;
-                        goto free_out;
-                }
-                        
                 switch (je16_to_cpu(node.u.nodetype)) {
+                        
                 case JFFS2_NODETYPE_DIRENT:
                         D1(printk(KERN_DEBUG "Node at %08x (%d) is a dirent node\n", ref_offset(ref), ref_flags(ref)));
-                        if (ref_flags(ref) == REF_UNCHECKED) {
-                                printk(KERN_WARNING "BUG: Dirent node at 0x%08x never got checked? How?\n", ref_offset(ref));
-                                BUG();
-                        }
+                        
                         if (retlen < sizeof(node.d)) {
-                                printk(KERN_WARNING "short read in get_inode_nodes()\n");
+                                printk(KERN_WARNING "Warning! Short read dirent at %#08x\n", ref_offset(ref));
                                 err = -EIO;
                                 goto free_out;
                         }
-                        /* sanity check */
-                        if (PAD((node.d.nsize + sizeof (node.d))) != PAD(je32_to_cpu (node.d.totlen))) {
-                                printk(KERN_NOTICE "jffs2_get_inode_nodes(): Illegal nsize in node at 0x%08x: nsize 0x%02x, totlen %04x\n",
-                                       ref_offset(ref), node.d.nsize, je32_to_cpu(node.d.totlen));
+
+                        err = read_direntry(c, ref, &node.d, retlen, &ret_fd, latest_mctime, mctime_ver);
+                        if (err == 1) {
                                 jffs2_mark_node_obsolete(c, ref);
-                                spin_lock(&c->erase_completion_lock);
-                                continue;
-                        }
+                                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 (ref_obsolete(ref)) {
-                                /* Obsoleted. This cannot happen, surely? dwmw2 20020308 */
-                                printk(KERN_ERR "Dirent node at 0x%08x became obsolete while we weren't looking\n",
-                                       ref_offset(ref));
-                                BUG();
-                        }
-                        
-                        fd = jffs2_alloc_full_dirent(node.d.nsize+1);
-                        if (!fd) {
-                                err = -ENOMEM;
-                                goto free_out;
-                        }
-                        fd->raw = ref;
-                        fd->version = je32_to_cpu(node.d.version);
-                        fd->ino = je32_to_cpu(node.d.ino);
-                        fd->type = node.d.type;
-
-                        /* Pick out the mctime of the latest dirent */
-                        if(fd->version > *mctime_ver) {
-                                *mctime_ver = fd->version;
-                                *latest_mctime = je32_to_cpu(node.d.mctime);
-                        }
 
-                        /* memcpy as much of the name as possible from the raw
-                           dirent we've already read from the flash
-                        */
-                        if (retlen > sizeof(struct jffs2_raw_dirent))
-                                memcpy(&fd->name[0], &node.d.name[0], min_t(uint32_t, node.d.nsize, (retlen-sizeof(struct jffs2_raw_dirent))));
-                                
-                        /* Do we need to copy any more of the name directly
-                           from the flash?
-                        */
-                        if (node.d.nsize + sizeof(struct jffs2_raw_dirent) > retlen) {
-                                /* FIXME: point() */
-                                int already = retlen - sizeof(struct jffs2_raw_dirent);
-                                        
-                                err = jffs2_flash_read(c, (ref_offset(ref)) + retlen, 
-                                                   node.d.nsize - already, &retlen, &fd->name[already]);
-                                if (!err && retlen != node.d.nsize - already)
-                                        err = -EIO;
-                                        
-                                if (err) {
-                                        printk(KERN_WARNING "Read remainder of name in jffs2_get_inode_nodes(): error %d\n", err);
-                                        jffs2_free_full_dirent(fd);
-                                        goto free_out;
-                                }
-                        }
-                        fd->nhash = full_name_hash(fd->name, node.d.nsize);
-                        fd->next = NULL;
-                        fd->name[node.d.nsize] = '\0';
-                                /* Wheee. We now have a complete jffs2_full_dirent structure, with
-                                   the name in it and everything. Link it into the list 
-                                */
-                        D1(printk(KERN_DEBUG "Adding fd \"%s\", ino #%u\n", fd->name, fd->ino));
-                        jffs2_add_fd_to_list(c, fd, &ret_fd);
                         break;
 
                 case JFFS2_NODETYPE_INODE:
                         D1(printk(KERN_DEBUG "Node at %08x (%d) is a data node\n", ref_offset(ref), ref_flags(ref)));
+                        
                         if (retlen < sizeof(node.i)) {
-                                printk(KERN_WARNING "read too short for dnode\n");
+                                printk(KERN_WARNING "Warning! Short read dnode at %#08x\n", ref_offset(ref));
                                 err = -EIO;
                                 goto free_out;
                         }
-                        if (je32_to_cpu(node.i.version) > *highest_version)
-                                *highest_version = je32_to_cpu(node.i.version);
-                        D1(printk(KERN_DEBUG "version %d, highest_version now %d\n", je32_to_cpu(node.i.version), *highest_version));
-
-                        if (ref_obsolete(ref)) {
-                                /* Obsoleted. This cannot happen, surely? dwmw2 20020308 */
-                                printk(KERN_ERR "Inode node at 0x%08x became obsolete while we weren't looking\n",
-                                       ref_offset(ref));
-                                BUG();
-                        }
-
-                        /* If we've never checked the CRCs on this node, check them now. */
-                        if (ref_flags(ref) == REF_UNCHECKED) {
-                                uint32_t crc, len;
-                                struct jffs2_eraseblock *jeb;
-
-                                crc = crc32(0, &node, sizeof(node.i)-8);
-                                if (crc != je32_to_cpu(node.i.node_crc)) {
-                                        printk(KERN_NOTICE "jffs2_get_inode_nodes(): CRC failed on node at 0x%08x: Read 0x%08x, calculated 0x%08x\n",
-                                               ref_offset(ref), je32_to_cpu(node.i.node_crc), crc);
-                                        jffs2_mark_node_obsolete(c, ref);
-                                        spin_lock(&c->erase_completion_lock);
-                                        continue;
-                                }
-                                
-                                /* sanity checks */
-                                if ( je32_to_cpu(node.i.offset) > je32_to_cpu(node.i.isize) ||
-                                     PAD(je32_to_cpu(node.i.csize) + sizeof (node.i)) != PAD(je32_to_cpu(node.i.totlen))) {
-                                        printk(KERN_NOTICE "jffs2_get_inode_nodes(): Inode corrupted at 0x%08x, totlen %d, #ino  %d, version %d, isize %d, csize %d, dsize %d \n",
-                                                ref_offset(ref),  je32_to_cpu(node.i.totlen),  je32_to_cpu(node.i.ino),
-                                                je32_to_cpu(node.i.version),  je32_to_cpu(node.i.isize), 
-                                                je32_to_cpu(node.i.csize), je32_to_cpu(node.i.dsize));
-                                        jffs2_mark_node_obsolete(c, ref);
-                                        spin_lock(&c->erase_completion_lock);
-                                        continue;
-                                }
 
-                                if (node.i.compr != JFFS2_COMPR_ZERO && je32_to_cpu(node.i.csize)) {
-                                        unsigned char *buf=NULL;
-                                        uint32_t pointed = 0;
-#ifndef __ECOS
-                                        if (c->mtd->point) {
-                                                err = c->mtd->point (c->mtd, ref_offset(ref) + sizeof(node.i), je32_to_cpu(node.i.csize),
-                                                                     &retlen, &buf);
-                                                if (!err && retlen < je32_to_cpu(node.i.csize)) {
-                                                        D1(printk(KERN_DEBUG "MTD point returned len too short: 0x%zx\n", retlen));
-                                                        c->mtd->unpoint(c->mtd, buf, ref_offset(ref) + sizeof(node.i), je32_to_cpu(node.i.csize));
-                                                } else if (err){
-                                                        D1(printk(KERN_DEBUG "MTD point failed %d\n", err));
-                                                } else
-                                                        pointed = 1; /* succefully pointed to device */
-                                        }
-#endif                                  
-                                        if(!pointed){
-                                                buf = kmalloc(je32_to_cpu(node.i.csize), GFP_KERNEL);
-                                                if (!buf)
-                                                        return -ENOMEM;
-                                                
-                                                err = jffs2_flash_read(c, ref_offset(ref) + sizeof(node.i), je32_to_cpu(node.i.csize),
-                                                                       &retlen, buf);
-                                                if (!err && retlen != je32_to_cpu(node.i.csize))
-                                                        err = -EIO;
-                                                if (err) {
-                                                        kfree(buf);
-                                                        return err;
-                                                }
-                                        }
-                                        crc = crc32(0, buf, je32_to_cpu(node.i.csize));
-                                        if(!pointed)
-                                                kfree(buf);
-#ifndef __ECOS
-                                        else
-                                                c->mtd->unpoint(c->mtd, buf, ref_offset(ref) + sizeof(node.i), je32_to_cpu(node.i.csize));
-#endif
-
-                                        if (crc != je32_to_cpu(node.i.data_crc)) {
-                                                printk(KERN_NOTICE "jffs2_get_inode_nodes(): Data CRC failed on node at 0x%08x: Read 0x%08x, calculated 0x%08x\n",
-                                                       ref_offset(ref), je32_to_cpu(node.i.data_crc), crc);
-                                                jffs2_mark_node_obsolete(c, ref);
-                                                spin_lock(&c->erase_completion_lock);
-                                                continue;
-                                        }
-                                        
-                                }
-
-                                /* Mark the node as having been checked and fix the accounting accordingly */
-                                spin_lock(&c->erase_completion_lock);
-                                jeb = &c->blocks[ref->flash_offset / c->sector_size];
-                                len = ref_totlen(c, jeb, ref);
-
-                                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 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(node.i.dsize) >= PAGE_CACHE_SIZE) ||
-                                    ( ((je32_to_cpu(node.i.offset)&(PAGE_CACHE_SIZE-1))==0) &&
-                                      (je32_to_cpu(node.i.dsize)+je32_to_cpu(node.i.offset) ==  je32_to_cpu(node.i.isize)))) {
-                                        D1(printk(KERN_DEBUG "Marking node at 0x%08x REF_PRISTINE\n", ref_offset(ref)));
-                                        ref->flash_offset = ref_offset(ref) | REF_PRISTINE;
-                                } else {
-                                        D1(printk(KERN_DEBUG "Marking node at 0x%08x REF_NORMAL\n", ref_offset(ref)));
-                                        ref->flash_offset = ref_offset(ref) | REF_NORMAL;
-                                }
-                                spin_unlock(&c->erase_completion_lock);
-                        }
-
-                        tn = jffs2_alloc_tmp_dnode_info();
-                        if (!tn) {
-                                D1(printk(KERN_DEBUG "alloc tn failed\n"));
-                                err = -ENOMEM;
+                        err = read_dnode(c, ref, &node.i, retlen, &ret_tn, latest_mctime, mctime_ver);
+                        if (err == 1) {
+                                jffs2_mark_node_obsolete(c, ref);
+                                break;
+                        } else if (unlikely(err))
                                 goto free_out;
-                        }
 
-                        tn->fn = jffs2_alloc_full_dnode();
-                        if (!tn->fn) {
-                                D1(printk(KERN_DEBUG "alloc fn failed\n"));
-                                err = -ENOMEM;
-                                jffs2_free_tmp_dnode_info(tn);
-                                goto free_out;
-                        }
-                        tn->version = je32_to_cpu(node.i.version);
-                        tn->fn->ofs = je32_to_cpu(node.i.offset);
-                        /* There was a bug where we wrote hole nodes out with
-                           csize/dsize swapped. Deal with it */
-                        if (node.i.compr == JFFS2_COMPR_ZERO && !je32_to_cpu(node.i.dsize) && je32_to_cpu(node.i.csize))
-                                tn->fn->size = je32_to_cpu(node.i.csize);
-                        else // normal case...
-                                tn->fn->size = je32_to_cpu(node.i.dsize);
-                        tn->fn->raw = ref;
-                        D1(printk(KERN_DEBUG "dnode @%08x: ver %u, offset %04x, dsize %04x\n",
-                                  ref_offset(ref), je32_to_cpu(node.i.version),
-                                  je32_to_cpu(node.i.offset), je32_to_cpu(node.i.dsize)));
-                        jffs2_add_tn_to_tree(tn, &ret_tn);
+                        if (je32_to_cpu(node.i.version) > *highest_version)
+                                *highest_version = je32_to_cpu(node.i.version);
+                        
+                        D1(printk(KERN_DEBUG "version %d, highest_version now %d\n",
+                                        je32_to_cpu(node.i.version), *highest_version));
+
                         break;
 
                 default:
-                        if (ref_flags(ref) == REF_UNCHECKED) {
-                                struct jffs2_eraseblock *jeb;
-                                uint32_t len;
-
-                                printk(KERN_ERR "Eep. Unknown node type %04x at %08x was marked REF_UNCHECKED\n",
-                                       je16_to_cpu(node.u.nodetype), ref_offset(ref));
-
-                                /* Mark the node as having been checked and fix the accounting accordingly */
-                                spin_lock(&c->erase_completion_lock);
-                                jeb = &c->blocks[ref->flash_offset / c->sector_size];
-                                len = ref_totlen(c, jeb, ref);
-
-                                jeb->used_size += len;
-                                jeb->unchecked_size -= len;
-                                c->used_size += len;
-                                c->unchecked_size -= len;
-
-                                mark_ref_normal(ref);
-                                spin_unlock(&c->erase_completion_lock);
+                        /* Check we've managed to read at least the common node header */
+                        if (retlen < sizeof(struct jffs2_unknown_node)) {
+                                printk(KERN_WARNING "Warning! Short read unknown node at %#08x\n",
+                                                ref_offset(ref));
+                                return -EIO;
                         }
-                        node.u.nodetype = cpu_to_je16(JFFS2_NODE_ACCURATE | je16_to_cpu(node.u.nodetype));
-                        if (crc32(0, &node, sizeof(struct jffs2_unknown_node)-4) != je32_to_cpu(node.u.hdr_crc)) {
-                                /* Hmmm. This should have been caught at scan time. */
-                                printk(KERN_ERR "Node header CRC failed at %08x. But it must have been OK earlier.\n",
-                                       ref_offset(ref));
-                                printk(KERN_ERR "Node was: { %04x, %04x, %08x, %08x }\n", 
-                                       je16_to_cpu(node.u.magic), je16_to_cpu(node.u.nodetype), je32_to_cpu(node.u.totlen),
-                                       je32_to_cpu(node.u.hdr_crc));
-                                jffs2_mark_node_obsolete(c, ref);
-                        } else switch(je16_to_cpu(node.u.nodetype) & JFFS2_COMPAT_MASK) {
-                        case JFFS2_FEATURE_INCOMPAT:
-                                printk(KERN_NOTICE "Unknown INCOMPAT nodetype %04X at %08x\n", je16_to_cpu(node.u.nodetype), ref_offset(ref));
-                                /* EEP */
-                                BUG();
-                                break;
-                        case JFFS2_FEATURE_ROCOMPAT:
-                                printk(KERN_NOTICE "Unknown ROCOMPAT nodetype %04X at %08x\n", je16_to_cpu(node.u.nodetype), ref_offset(ref));
-                                if (!(c->flags & JFFS2_SB_FLAG_RO))
-                                        BUG();
-                                break;
-                        case JFFS2_FEATURE_RWCOMPAT_COPY:
-                                printk(KERN_NOTICE "Unknown RWCOMPAT_COPY nodetype %04X at %08x\n", je16_to_cpu(node.u.nodetype), ref_offset(ref));
-                                break;
-                        case JFFS2_FEATURE_RWCOMPAT_DELETE:
-                                printk(KERN_NOTICE "Unknown RWCOMPAT_DELETE nodetype %04X at %08x\n", je16_to_cpu(node.u.nodetype), ref_offset(ref));
+
+                        err = read_unknown(c, ref, &node.u, retlen);
+                        if (err == 1) {
                                 jffs2_mark_node_obsolete(c, ref);
                                 break;
-                        }
+                        } else if (unlikely(err))
+                                goto free_out;
 
                 }
                 spin_lock(&c->erase_completion_lock);