yaffs direct: Fix wrong condition for O_CREAT | O_EXCL
[yaffs2.git] / yaffs_yaffs2.c
index ad35fd5..8c31a66 100644 (file)
@@ -1,7 +1,7 @@
 /*
  * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
  *
- * Copyright (C) 2002-2010 Aleph One Ltd.
+ * Copyright (C) 2002-2011 Aleph One Ltd.
  *   for Toby Churchill Ltd and Brightstar Engineering
  *
  * Created by Charles Manning <charles@aleph1.co.uk>
@@ -20,6 +20,7 @@
 #include "yaffs_getblockinfo.h"
 #include "yaffs_verify.h"
 #include "yaffs_attribs.h"
+#include "yaffs_summary.h"
 
 /*
  * Checkpoints are really no benefit on very small partitions.
@@ -28,7 +29,6 @@
  * the partition is at least this big.
  */
 #define YAFFS_CHECKPOINT_MIN_BLOCKS 60
-
 #define YAFFS_SMALL_HOLE_THRESHOLD 4
 
 /*
@@ -55,7 +55,8 @@ void yaffs_calc_oldest_dirty_seq(struct yaffs_dev *dev)
        for (i = dev->internal_start_block; i <= dev->internal_end_block; i++) {
                if (b->block_state == YAFFS_BLOCK_STATE_FULL &&
                    (b->pages_in_use - b->soft_del_pages) <
-                   dev->param.chunks_per_block && b->seq_number < seq) {
+                   dev->param.chunks_per_block &&
+                   b->seq_number < seq) {
                        seq = b->seq_number;
                        block_no = i;
                }
@@ -66,7 +67,6 @@ void yaffs_calc_oldest_dirty_seq(struct yaffs_dev *dev)
                dev->oldest_dirty_seq = seq;
                dev->oldest_dirty_block = block_no;
        }
-
 }
 
 void yaffs2_find_oldest_dirty_seq(struct yaffs_dev *dev)
@@ -81,7 +81,7 @@ void yaffs2_find_oldest_dirty_seq(struct yaffs_dev *dev)
 /*
  * yaffs_clear_oldest_dirty_seq()
  * Called when a block is erased or marked bad. (ie. when its seq_number
- * becomes invalid). If the value matches the oldest then we clear 
+ * becomes invalid). If the value matches the oldest then we clear
  * dev->oldest_dirty_seq to force its recomputation.
  */
 void yaffs2_clear_oldest_dirty_seq(struct yaffs_dev *dev,
@@ -127,8 +127,8 @@ int yaffs_block_ok_for_gc(struct yaffs_dev *dev, struct yaffs_block_info *bi)
 
        yaffs2_find_oldest_dirty_seq(dev);
 
-       /* Can't do gc of this block if there are any blocks older than this one that have
-        * discarded pages.
+       /* Can't do gc of this block if there are any blocks older than this
+        * one that have discarded pages.
         */
        return (bi->seq_number <= dev->oldest_dirty_seq);
 }
@@ -138,13 +138,11 @@ int yaffs_block_ok_for_gc(struct yaffs_dev *dev, struct yaffs_block_info *bi)
  * periodically finds the oldest full block by sequence number for refreshing.
  * Only for yaffs2.
  */
-u32 yaffs2_find_refresh_block(struct yaffs_dev * dev)
+u32 yaffs2_find_refresh_block(struct yaffs_dev *dev)
 {
        u32 b;
-
        u32 oldest = 0;
        u32 oldest_seq = 0;
-
        struct yaffs_block_info *bi;
 
        if (!dev->param.is_yaffs2)
@@ -186,10 +184,9 @@ u32 yaffs2_find_refresh_block(struct yaffs_dev * dev)
        }
 
        if (oldest > 0) {
-               T(YAFFS_TRACE_GC,
-                 (TSTR
-                  ("GC refresh count %d selected block %d with seq_number %d"
-                   TENDSTR), dev->refresh_count, oldest, oldest_seq));
+               yaffs_trace(YAFFS_TRACE_GC,
+                       "GC refresh count %d selected block %d with seq_number %d",
+                       dev->refresh_count, oldest, oldest_seq);
        }
 
        return oldest;
@@ -211,29 +208,29 @@ int yaffs2_checkpt_required(struct yaffs_dev *dev)
 int yaffs_calc_checkpt_blocks_required(struct yaffs_dev *dev)
 {
        int retval;
+       int n_bytes = 0;
+       int n_blocks;
+       int dev_blocks;
 
        if (!dev->param.is_yaffs2)
                return 0;
 
        if (!dev->checkpoint_blocks_required && yaffs2_checkpt_required(dev)) {
                /* Not a valid value so recalculate */
-               int n_bytes = 0;
-               int n_blocks;
-               int dev_blocks =
-                   (dev->param.end_block - dev->param.start_block + 1);
-
+               dev_blocks = dev->param.end_block - dev->param.start_block + 1;
                n_bytes += sizeof(struct yaffs_checkpt_validity);
                n_bytes += sizeof(struct yaffs_checkpt_dev);
                n_bytes += dev_blocks * sizeof(struct yaffs_block_info);
                n_bytes += dev_blocks * dev->chunk_bit_stride;
                n_bytes +=
-                   (sizeof(struct yaffs_checkpt_obj) +
-                    sizeof(u32)) * (dev->n_obj);
-               n_bytes += (dev->tnode_size + sizeof(u32)) * (dev->n_tnodes);
+                   (sizeof(struct yaffs_checkpt_obj) + sizeof(u32)) *
+                   dev->n_obj;
+               n_bytes += (dev->tnode_size + sizeof(u32)) * dev->n_tnodes;
                n_bytes += sizeof(struct yaffs_checkpt_validity);
                n_bytes += sizeof(u32); /* checksum */
 
-               /* Round up and add 2 blocks to allow for some bad blocks, so add 3 */
+               /* Round up and add 2 blocks to allow for some bad blocks,
+                * so add 3 */
 
                n_blocks =
                    (n_bytes /
@@ -313,9 +310,7 @@ static int yaffs2_wr_checkpt_dev(struct yaffs_dev *dev)
 {
        struct yaffs_checkpt_dev cp;
        u32 n_bytes;
-       u32 n_blocks =
-           (dev->internal_end_block - dev->internal_start_block + 1);
-
+       u32 n_blocks = dev->internal_end_block - dev->internal_start_block + 1;
        int ok;
 
        /* Write device runtime values */
@@ -323,22 +318,20 @@ static int yaffs2_wr_checkpt_dev(struct yaffs_dev *dev)
        cp.struct_type = sizeof(cp);
 
        ok = (yaffs2_checkpt_wr(dev, &cp, sizeof(cp)) == sizeof(cp));
+       if (!ok)
+               return 0;
 
        /* Write block info */
-       if (ok) {
-               n_bytes = n_blocks * sizeof(struct yaffs_block_info);
-               ok = (yaffs2_checkpt_wr(dev, dev->block_info, n_bytes) ==
-                     n_bytes);
-       }
+       n_bytes = n_blocks * sizeof(struct yaffs_block_info);
+       ok = (yaffs2_checkpt_wr(dev, dev->block_info, n_bytes) == n_bytes);
+       if (!ok)
+               return 0;
 
        /* Write chunk bits */
-       if (ok) {
-               n_bytes = n_blocks * dev->chunk_bit_stride;
-               ok = (yaffs2_checkpt_wr(dev, dev->chunk_bits, n_bytes) ==
-                     n_bytes);
-       }
-       return ok ? 1 : 0;
+       n_bytes = n_blocks * dev->chunk_bit_stride;
+       ok = (yaffs2_checkpt_wr(dev, dev->chunk_bits, n_bytes) == n_bytes);
 
+       return ok ? 1 : 0;
 }
 
 static int yaffs2_rd_checkpt_dev(struct yaffs_dev *dev)
@@ -347,7 +340,6 @@ static int yaffs2_rd_checkpt_dev(struct yaffs_dev *dev)
        u32 n_bytes;
        u32 n_blocks =
            (dev->internal_end_block - dev->internal_start_block + 1);
-
        int ok;
 
        ok = (yaffs2_checkpt_rd(dev, &cp, sizeof(cp)) == sizeof(cp));
@@ -365,6 +357,7 @@ static int yaffs2_rd_checkpt_dev(struct yaffs_dev *dev)
 
        if (!ok)
                return 0;
+
        n_bytes = n_blocks * dev->chunk_bit_stride;
 
        ok = (yaffs2_checkpt_rd(dev, dev->chunk_bits, n_bytes) == n_bytes);
@@ -375,7 +368,6 @@ static int yaffs2_rd_checkpt_dev(struct yaffs_dev *dev)
 static void yaffs2_obj_checkpt_obj(struct yaffs_checkpt_obj *cp,
                                   struct yaffs_obj *obj)
 {
-
        cp->obj_id = obj->obj_id;
        cp->parent_id = (obj->parent) ? obj->parent->obj_id : 0;
        cp->hdr_chunk = obj->hdr_chunk;
@@ -395,19 +387,16 @@ static void yaffs2_obj_checkpt_obj(struct yaffs_checkpt_obj *cp,
                cp->size_or_equiv_obj = obj->variant.hardlink_variant.equiv_id;
 }
 
-static int taffs2_checkpt_obj_to_obj(struct yaffs_obj *obj,
+static int yaffs2_checkpt_obj_to_obj(struct yaffs_obj *obj,
                                     struct yaffs_checkpt_obj *cp)
 {
-
        struct yaffs_obj *parent;
 
        if (obj->variant_type != cp->variant_type) {
-               T(YAFFS_TRACE_ERROR, (TSTR("Checkpoint read object %d type %d "
-                                          TCONT
-                                          ("chunk %d does not match existing object type %d")
-                                          TENDSTR), cp->obj_id,
-                                     cp->variant_type, cp->hdr_chunk,
-                                     obj->variant_type));
+               yaffs_trace(YAFFS_TRACE_ERROR,
+                       "Checkpoint read object %d type %d chunk %d does not match existing object type %d",
+                       cp->obj_id, cp->variant_type, cp->hdr_chunk,
+                       obj->variant_type);
                return 0;
        }
 
@@ -415,20 +404,18 @@ static int taffs2_checkpt_obj_to_obj(struct yaffs_obj *obj,
 
        if (cp->parent_id)
                parent = yaffs_find_or_create_by_number(obj->my_dev,
-                                                       cp->parent_id,
-                                                       YAFFS_OBJECT_TYPE_DIRECTORY);
+                                               cp->parent_id,
+                                               YAFFS_OBJECT_TYPE_DIRECTORY);
        else
                parent = NULL;
 
        if (parent) {
                if (parent->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY) {
-                       T(YAFFS_TRACE_ALWAYS,
-                         (TSTR
-                          ("Checkpoint read object %d parent %d type %d"
-                           TCONT(" chunk %d Parent type, %d, not directory")
-                           TENDSTR), cp->obj_id, cp->parent_id,
-                          cp->variant_type, cp->hdr_chunk,
-                          parent->variant_type));
+                       yaffs_trace(YAFFS_TRACE_ALWAYS,
+                               "Checkpoint read object %d parent %d type %d chunk %d Parent type, %d, not directory",
+                               cp->obj_id, cp->parent_id,
+                               cp->variant_type, cp->hdr_chunk,
+                               parent->variant_type);
                        return 0;
                }
                yaffs_add_obj_to_dir(parent, obj);
@@ -462,39 +449,33 @@ static int yaffs2_checkpt_tnode_worker(struct yaffs_obj *in,
        int i;
        struct yaffs_dev *dev = in->my_dev;
        int ok = 1;
-
-       if (tn) {
-               if (level > 0) {
-
-                       for (i = 0; i < YAFFS_NTNODES_INTERNAL && ok; i++) {
-                               if (tn->internal[i]) {
-                                       ok = yaffs2_checkpt_tnode_worker(in,
-                                                                        tn->
-                                                                        internal
-                                                                        [i],
-                                                                        level -
-                                                                        1,
-                                                                        (chunk_offset
-                                                                         <<
-                                                                         YAFFS_TNODES_INTERNAL_BITS)
-                                                                        + i);
-                               }
-                       }
-               } else if (level == 0) {
-                       u32 base_offset =
-                           chunk_offset << YAFFS_TNODES_LEVEL0_BITS;
-                       ok = (yaffs2_checkpt_wr
-                             (dev, &base_offset,
-                              sizeof(base_offset)) == sizeof(base_offset));
-                       if (ok)
-                               ok = (yaffs2_checkpt_wr
-                                     (dev, tn,
-                                      dev->tnode_size) == dev->tnode_size);
+       u32 base_offset;
+
+       if (!tn)
+               return 1;
+
+       if (level > 0) {
+               for (i = 0; i < YAFFS_NTNODES_INTERNAL && ok; i++) {
+                       if (!tn->internal[i])
+                               continue;
+                       ok = yaffs2_checkpt_tnode_worker(in,
+                                tn->internal[i],
+                                level - 1,
+                                (chunk_offset <<
+                                 YAFFS_TNODES_INTERNAL_BITS) + i);
                }
+               return ok;
        }
 
-       return ok;
+       /* Level 0 tnode */
+       base_offset = chunk_offset << YAFFS_TNODES_LEVEL0_BITS;
+       ok = (yaffs2_checkpt_wr(dev, &base_offset, sizeof(base_offset)) ==
+                       sizeof(base_offset));
+       if (ok)
+               ok = (yaffs2_checkpt_wr(dev, tn, dev->tnode_size) ==
+                       dev->tnode_size);
 
+       return ok;
 }
 
 static int yaffs2_wr_checkpt_tnodes(struct yaffs_obj *obj)
@@ -502,16 +483,16 @@ static int yaffs2_wr_checkpt_tnodes(struct yaffs_obj *obj)
        u32 end_marker = ~0;
        int ok = 1;
 
-       if (obj->variant_type == YAFFS_OBJECT_TYPE_FILE) {
-               ok = yaffs2_checkpt_tnode_worker(obj,
-                                                obj->variant.file_variant.top,
-                                                obj->variant.file_variant.
-                                                top_level, 0);
-               if (ok)
-                       ok = (yaffs2_checkpt_wr
-                             (obj->my_dev, &end_marker,
-                              sizeof(end_marker)) == sizeof(end_marker));
-       }
+       if (obj->variant_type != YAFFS_OBJECT_TYPE_FILE)
+               return ok;
+
+       ok = yaffs2_checkpt_tnode_worker(obj,
+                                        obj->variant.file_variant.top,
+                                        obj->variant.file_variant.
+                                        top_level, 0);
+       if (ok)
+               ok = (yaffs2_checkpt_wr(obj->my_dev, &end_marker,
+                               sizeof(end_marker)) == sizeof(end_marker));
 
        return ok ? 1 : 0;
 }
@@ -533,12 +514,11 @@ static int yaffs2_rd_checkpt_tnodes(struct yaffs_obj *obj)
                /* Read level 0 tnode */
 
                tn = yaffs_get_tnode(dev);
-               if (tn) {
+               if (tn)
                        ok = (yaffs2_checkpt_rd(dev, tn, dev->tnode_size) ==
-                             dev->tnode_size);
-               } else {
+                               dev->tnode_size);
+               else
                        ok = 0;
-                }
 
                if (tn && ok)
                        ok = yaffs_add_find_tnode_0(dev,
@@ -549,12 +529,11 @@ static int yaffs2_rd_checkpt_tnodes(struct yaffs_obj *obj)
                        ok = (yaffs2_checkpt_rd
                              (dev, &base_chunk,
                               sizeof(base_chunk)) == sizeof(base_chunk));
-
        }
 
-       T(YAFFS_TRACE_CHECKPOINT,
-         (TSTR("Checkpoint read tnodes %d records, last %d. ok %d" TENDSTR),
-          nread, base_chunk, ok));
+       yaffs_trace(YAFFS_TRACE_CHECKPOINT,
+               "Checkpoint read tnodes %d records, last %d. ok %d",
+               nread, base_chunk, ok);
 
        return ok ? 1 : 0;
 }
@@ -573,35 +552,29 @@ static int yaffs2_wr_checkpt_objs(struct yaffs_dev *dev)
 
        for (i = 0; ok && i < YAFFS_NOBJECT_BUCKETS; i++) {
                list_for_each(lh, &dev->obj_bucket[i].list) {
-                       if (lh) {
-                               obj =
-                                   list_entry(lh, struct yaffs_obj, hash_link);
-                               if (!obj->defered_free) {
-                                       yaffs2_obj_checkpt_obj(&cp, obj);
-                                       cp.struct_type = sizeof(cp);
-
-                                       T(YAFFS_TRACE_CHECKPOINT,
-                                         (TSTR
-                                          ("Checkpoint write object %d parent %d type %d chunk %d obj addr %p"
-                                           TENDSTR), cp.obj_id, cp.parent_id,
-                                          cp.variant_type, cp.hdr_chunk, obj));
-
-                                       ok = (yaffs2_checkpt_wr
-                                             (dev, &cp,
-                                              sizeof(cp)) == sizeof(cp));
-
-                                       if (ok
-                                           && obj->variant_type ==
-                                           YAFFS_OBJECT_TYPE_FILE)
-                                               ok = yaffs2_wr_checkpt_tnodes
-                                                   (obj);
-                               }
+                       obj = list_entry(lh, struct yaffs_obj, hash_link);
+                       if (!obj->defered_free) {
+                               yaffs2_obj_checkpt_obj(&cp, obj);
+                               cp.struct_type = sizeof(cp);
+
+                               yaffs_trace(YAFFS_TRACE_CHECKPOINT,
+                                       "Checkpoint write object %d parent %d type %d chunk %d obj addr %p",
+                                       cp.obj_id, cp.parent_id,
+                                       cp.variant_type, cp.hdr_chunk, obj);
+
+                               ok = (yaffs2_checkpt_wr(dev, &cp,
+                                               sizeof(cp)) == sizeof(cp));
+
+                               if (ok &&
+                                       obj->variant_type ==
+                                       YAFFS_OBJECT_TYPE_FILE)
+                                       ok = yaffs2_wr_checkpt_tnodes(obj);
                        }
                }
        }
 
        /* Dump end of list */
-       memset(&cp, 0xFF, sizeof(struct yaffs_checkpt_obj));
+       memset(&cp, 0xff, sizeof(struct yaffs_checkpt_obj));
        cp.struct_type = sizeof(cp);
 
        if (ok)
@@ -616,22 +589,22 @@ static int yaffs2_rd_checkpt_objs(struct yaffs_dev *dev)
        struct yaffs_checkpt_obj cp;
        int ok = 1;
        int done = 0;
-       struct yaffs_obj *hard_list = NULL;
+       LIST_HEAD(hard_list);
+
 
        while (ok && !done) {
                ok = (yaffs2_checkpt_rd(dev, &cp, sizeof(cp)) == sizeof(cp));
                if (cp.struct_type != sizeof(cp)) {
-                       T(YAFFS_TRACE_CHECKPOINT,
-                         (TSTR("struct size %d instead of %d ok %d" TENDSTR),
-                          cp.struct_type, (int)sizeof(cp), ok));
+                       yaffs_trace(YAFFS_TRACE_CHECKPOINT,
+                               "struct size %d instead of %d ok %d",
+                               cp.struct_type, (int)sizeof(cp), ok);
                        ok = 0;
                }
 
-               T(YAFFS_TRACE_CHECKPOINT,
-                 (TSTR
-                  ("Checkpoint read object %d parent %d type %d chunk %d "
-                   TENDSTR), cp.obj_id, cp.parent_id, cp.variant_type,
-                  cp.hdr_chunk));
+               yaffs_trace(YAFFS_TRACE_CHECKPOINT,
+                       "Checkpoint read object %d parent %d type %d chunk %d ",
+                       cp.obj_id, cp.parent_id, cp.variant_type,
+                       cp.hdr_chunk);
 
                if (ok && cp.obj_id == ~0) {
                        done = 1;
@@ -640,25 +613,24 @@ static int yaffs2_rd_checkpt_objs(struct yaffs_dev *dev)
                            yaffs_find_or_create_by_number(dev, cp.obj_id,
                                                           cp.variant_type);
                        if (obj) {
-                               ok = taffs2_checkpt_obj_to_obj(obj, &cp);
+                               ok = yaffs2_checkpt_obj_to_obj(obj, &cp);
                                if (!ok)
                                        break;
-                               if (obj->variant_type == YAFFS_OBJECT_TYPE_FILE) {
+                               if (obj->variant_type ==
+                                       YAFFS_OBJECT_TYPE_FILE) {
                                        ok = yaffs2_rd_checkpt_tnodes(obj);
                                } else if (obj->variant_type ==
-                                          YAFFS_OBJECT_TYPE_HARDLINK) {
-                                       obj->hard_links.next =
-                                           (struct list_head *)hard_list;
-                                       hard_list = obj;
+                                       YAFFS_OBJECT_TYPE_HARDLINK) {
+                                       list_add(&obj->hard_links, &hard_list);
                                }
                        } else {
                                ok = 0;
-                        }
+                       }
                }
        }
 
        if (ok)
-               yaffs_link_fixup(dev, hard_list);
+               yaffs_link_fixup(dev, &hard_list);
 
        return ok ? 1 : 0;
 }
@@ -671,7 +643,7 @@ static int yaffs2_wr_checkpt_sum(struct yaffs_dev *dev)
        yaffs2_get_checkpt_sum(dev, &checkpt_sum);
 
        ok = (yaffs2_checkpt_wr(dev, &checkpt_sum, sizeof(checkpt_sum)) ==
-             sizeof(checkpt_sum));
+               sizeof(checkpt_sum));
 
        if (!ok)
                return 0;
@@ -688,7 +660,7 @@ static int yaffs2_rd_checkpt_sum(struct yaffs_dev *dev)
        yaffs2_get_checkpt_sum(dev, &checkpt_sum0);
 
        ok = (yaffs2_checkpt_rd(dev, &checkpt_sum1, sizeof(checkpt_sum1)) ==
-             sizeof(checkpt_sum1));
+               sizeof(checkpt_sum1));
 
        if (!ok)
                return 0;
@@ -704,8 +676,8 @@ static int yaffs2_wr_checkpt_data(struct yaffs_dev *dev)
        int ok = 1;
 
        if (!yaffs2_checkpt_required(dev)) {
-               T(YAFFS_TRACE_CHECKPOINT,
-                 (TSTR("skipping checkpoint write" TENDSTR)));
+               yaffs_trace(YAFFS_TRACE_CHECKPOINT,
+                       "skipping checkpoint write");
                ok = 0;
        }
 
@@ -713,23 +685,23 @@ static int yaffs2_wr_checkpt_data(struct yaffs_dev *dev)
                ok = yaffs2_checkpt_open(dev, 1);
 
        if (ok) {
-               T(YAFFS_TRACE_CHECKPOINT,
-                 (TSTR("write checkpoint validity" TENDSTR)));
+               yaffs_trace(YAFFS_TRACE_CHECKPOINT,
+                       "write checkpoint validity");
                ok = yaffs2_wr_checkpt_validity_marker(dev, 1);
        }
        if (ok) {
-               T(YAFFS_TRACE_CHECKPOINT,
-                 (TSTR("write checkpoint device" TENDSTR)));
+               yaffs_trace(YAFFS_TRACE_CHECKPOINT,
+                       "write checkpoint device");
                ok = yaffs2_wr_checkpt_dev(dev);
        }
        if (ok) {
-               T(YAFFS_TRACE_CHECKPOINT,
-                 (TSTR("write checkpoint objects" TENDSTR)));
+               yaffs_trace(YAFFS_TRACE_CHECKPOINT,
+                       "write checkpoint objects");
                ok = yaffs2_wr_checkpt_objs(dev);
        }
        if (ok) {
-               T(YAFFS_TRACE_CHECKPOINT,
-                 (TSTR("write checkpoint validity" TENDSTR)));
+               yaffs_trace(YAFFS_TRACE_CHECKPOINT,
+                       "write checkpoint validity");
                ok = yaffs2_wr_checkpt_validity_marker(dev, 0);
        }
 
@@ -755,39 +727,39 @@ static int yaffs2_rd_checkpt_data(struct yaffs_dev *dev)
                ok = 0;
 
        if (ok && dev->param.skip_checkpt_rd) {
-               T(YAFFS_TRACE_CHECKPOINT,
-                 (TSTR("skipping checkpoint read" TENDSTR)));
+               yaffs_trace(YAFFS_TRACE_CHECKPOINT,
+                       "skipping checkpoint read");
                ok = 0;
        }
 
        if (ok)
-               ok = yaffs2_checkpt_open(dev, 0);       /* open for read */
+               ok = yaffs2_checkpt_open(dev, 0); /* open for read */
 
        if (ok) {
-               T(YAFFS_TRACE_CHECKPOINT,
-                 (TSTR("read checkpoint validity" TENDSTR)));
+               yaffs_trace(YAFFS_TRACE_CHECKPOINT,
+                       "read checkpoint validity");
                ok = yaffs2_rd_checkpt_validity_marker(dev, 1);
        }
        if (ok) {
-               T(YAFFS_TRACE_CHECKPOINT,
-                 (TSTR("read checkpoint device" TENDSTR)));
+               yaffs_trace(YAFFS_TRACE_CHECKPOINT,
+                       "read checkpoint device");
                ok = yaffs2_rd_checkpt_dev(dev);
        }
        if (ok) {
-               T(YAFFS_TRACE_CHECKPOINT,
-                 (TSTR("read checkpoint objects" TENDSTR)));
+               yaffs_trace(YAFFS_TRACE_CHECKPOINT,
+                       "read checkpoint objects");
                ok = yaffs2_rd_checkpt_objs(dev);
        }
        if (ok) {
-               T(YAFFS_TRACE_CHECKPOINT,
-                 (TSTR("read checkpoint validity" TENDSTR)));
+               yaffs_trace(YAFFS_TRACE_CHECKPOINT,
+                       "read checkpoint validity");
                ok = yaffs2_rd_checkpt_validity_marker(dev, 0);
        }
 
        if (ok) {
                ok = yaffs2_rd_checkpt_sum(dev);
-               T(YAFFS_TRACE_CHECKPOINT,
-                 (TSTR("read checkpoint checksum %d" TENDSTR), ok));
+               yaffs_trace(YAFFS_TRACE_CHECKPOINT,
+                       "read checkpoint checksum %d", ok);
        }
 
        if (!yaffs_checkpt_close(dev))
@@ -799,7 +771,6 @@ static int yaffs2_rd_checkpt_data(struct yaffs_dev *dev)
                dev->is_checkpointed = 0;
 
        return ok ? 1 : 0;
-
 }
 
 void yaffs2_checkpt_invalidate(struct yaffs_dev *dev)
@@ -814,10 +785,9 @@ void yaffs2_checkpt_invalidate(struct yaffs_dev *dev)
 
 int yaffs_checkpoint_save(struct yaffs_dev *dev)
 {
-
-       T(YAFFS_TRACE_CHECKPOINT,
-         (TSTR("save entry: is_checkpointed %d" TENDSTR),
-          dev->is_checkpointed));
+       yaffs_trace(YAFFS_TRACE_CHECKPOINT,
+               "save entry: is_checkpointed %d",
+               dev->is_checkpointed);
 
        yaffs_verify_objects(dev);
        yaffs_verify_blocks(dev);
@@ -828,9 +798,9 @@ int yaffs_checkpoint_save(struct yaffs_dev *dev)
                yaffs2_wr_checkpt_data(dev);
        }
 
-       T(YAFFS_TRACE_ALWAYS,
-         (TSTR("save exit: is_checkpointed %d" TENDSTR),
-          dev->is_checkpointed));
+       yaffs_trace(YAFFS_TRACE_CHECKPOINT | YAFFS_TRACE_MOUNT,
+               "save exit: is_checkpointed %d",
+               dev->is_checkpointed);
 
        return dev->is_checkpointed;
 }
@@ -838,9 +808,10 @@ int yaffs_checkpoint_save(struct yaffs_dev *dev)
 int yaffs2_checkpt_restore(struct yaffs_dev *dev)
 {
        int retval;
-       T(YAFFS_TRACE_CHECKPOINT,
-         (TSTR("restore entry: is_checkpointed %d" TENDSTR),
-          dev->is_checkpointed));
+
+       yaffs_trace(YAFFS_TRACE_CHECKPOINT,
+               "restore entry: is_checkpointed %d",
+               dev->is_checkpointed);
 
        retval = yaffs2_rd_checkpt_data(dev);
 
@@ -850,9 +821,9 @@ int yaffs2_checkpt_restore(struct yaffs_dev *dev)
                yaffs_verify_free_chunks(dev);
        }
 
-       T(YAFFS_TRACE_CHECKPOINT,
-         (TSTR("restore exit: is_checkpointed %d" TENDSTR),
-          dev->is_checkpointed));
+       yaffs_trace(YAFFS_TRACE_CHECKPOINT,
+               "restore exit: is_checkpointed %d",
+               dev->is_checkpointed);
 
        return retval;
 }
@@ -861,17 +832,15 @@ int yaffs2_handle_hole(struct yaffs_obj *obj, loff_t new_size)
 {
        /* if new_size > old_file_size.
         * We're going to be writing a hole.
-        * If the hole is small then write zeros otherwise write a start of hole marker.
+        * If the hole is small then write zeros otherwise write a start
+        * of hole marker.
         */
-
        loff_t old_file_size;
-       int increase;
+       loff_t increase;
        int small_hole;
        int result = YAFFS_OK;
        struct yaffs_dev *dev = NULL;
-
        u8 *local_buffer = NULL;
-
        int small_increase_ok = 0;
 
        if (!obj)
@@ -900,11 +869,11 @@ int yaffs2_handle_hole(struct yaffs_obj *obj, loff_t new_size)
                small_hole = 0;
 
        if (small_hole)
-               local_buffer = yaffs_get_temp_buffer(dev, __LINE__);
+               local_buffer = yaffs_get_temp_buffer(dev);
 
        if (local_buffer) {
                /* fill hole with zero bytes */
-               int pos = old_file_size;
+               loff_t pos = old_file_size;
                int this_write;
                int written;
                memset(local_buffer, 0, dev->data_bytes_per_chunk);
@@ -922,12 +891,12 @@ int yaffs2_handle_hole(struct yaffs_obj *obj, loff_t new_size)
                                increase -= this_write;
                        } else {
                                small_increase_ok = 0;
-                        }
+                       }
                }
 
-               yaffs_release_temp_buffer(dev, local_buffer, __LINE__);
+               yaffs_release_temp_buffer(dev, local_buffer);
 
-               /* If we were out of space then reverse any chunks we've added */
+               /* If out of space then reverse any chunks we've added */
                if (!small_increase_ok)
                        yaffs_resize_file_down(obj, old_file_size);
        }
@@ -941,7 +910,6 @@ int yaffs2_handle_hole(struct yaffs_obj *obj, loff_t new_size)
        }
 
        return result;
-
 }
 
 struct yaffs_block_index {
@@ -955,71 +923,471 @@ static int yaffs2_ybicmp(const void *a, const void *b)
        int bseq = ((struct yaffs_block_index *)b)->seq;
        int ablock = ((struct yaffs_block_index *)a)->block;
        int bblock = ((struct yaffs_block_index *)b)->block;
+
        if (aseq == bseq)
                return ablock - bblock;
-       else
-               return aseq - bseq;
+
+       return aseq - bseq;
 }
 
-int yaffs2_scan_backwards(struct yaffs_dev *dev)
+static inline int yaffs2_scan_chunk(struct yaffs_dev *dev,
+               struct yaffs_block_info *bi,
+               int blk, int chunk_in_block,
+               int *found_chunks,
+               u8 *chunk_data,
+               struct list_head *hard_list,
+               int summary_available)
 {
+       struct yaffs_obj_hdr *oh;
+       struct yaffs_obj *in;
+       struct yaffs_obj *parent;
+       int equiv_id;
+       loff_t file_size;
+       int is_shrink;
+       int is_unlinked;
        struct yaffs_ext_tags tags;
+       int result;
+       int alloc_failed = 0;
+       int chunk = blk * dev->param.chunks_per_block + chunk_in_block;
+       struct yaffs_file_var *file_var;
+       struct yaffs_hardlink_var *hl_var;
+       struct yaffs_symlink_var *sl_var;
+
+       if (summary_available) {
+               result = yaffs_summary_fetch(dev, &tags, chunk_in_block);
+               tags.seq_number = bi->seq_number;
+       }
+
+       if (!summary_available || tags.obj_id == 0) {
+               result = yaffs_rd_chunk_tags_nand(dev, chunk, NULL, &tags);
+               dev->tags_used++;
+       } else {
+               dev->summary_used++;
+       }
+
+       /* Let's have a good look at this chunk... */
+
+       if (!tags.chunk_used) {
+               /* An unassigned chunk in the block.
+                * If there are used chunks after this one, then
+                * it is a chunk that was skipped due to failing
+                * the erased check. Just skip it so that it can
+                * be deleted.
+                * But, more typically, We get here when this is
+                * an unallocated chunk and his means that
+                * either the block is empty or this is the one
+                * being allocated from
+                */
+
+               if (*found_chunks) {
+                       /* This is a chunk that was skipped due
+                        * to failing the erased check */
+               } else if (chunk_in_block == 0) {
+                       /* We're looking at the first chunk in
+                        * the block so the block is unused */
+                       bi->block_state = YAFFS_BLOCK_STATE_EMPTY;
+                       dev->n_erased_blocks++;
+               } else {
+                       if (bi->block_state == YAFFS_BLOCK_STATE_NEEDS_SCAN ||
+                           bi->block_state == YAFFS_BLOCK_STATE_ALLOCATING) {
+                               if (dev->seq_number == bi->seq_number) {
+                                       /* Allocating from this block*/
+                                       yaffs_trace(YAFFS_TRACE_SCAN,
+                                           " Allocating from %d %d",
+                                           blk, chunk_in_block);
+
+                                       bi->block_state =
+                                               YAFFS_BLOCK_STATE_ALLOCATING;
+                                       dev->alloc_block = blk;
+                                       dev->alloc_page = chunk_in_block;
+                                       dev->alloc_block_finder = blk;
+                               } else {
+                                       /* This is a partially written block
+                                        * that is not the current
+                                        * allocation block.
+                                        */
+                                       yaffs_trace(YAFFS_TRACE_SCAN,
+                                               "Partially written block %d detected. gc will fix this.",
+                                               blk);
+                               }
+                       }
+               }
+
+               dev->n_free_chunks++;
+
+       } else if (tags.ecc_result ==
+               YAFFS_ECC_RESULT_UNFIXED) {
+               yaffs_trace(YAFFS_TRACE_SCAN,
+                       " Unfixed ECC in chunk(%d:%d), chunk ignored",
+                       blk, chunk_in_block);
+                       dev->n_free_chunks++;
+       } else if (tags.obj_id > YAFFS_MAX_OBJECT_ID ||
+                  tags.chunk_id > YAFFS_MAX_CHUNK_ID ||
+                  tags.obj_id == YAFFS_OBJECTID_SUMMARY ||
+                  (tags.chunk_id > 0 &&
+                    tags.n_bytes > dev->data_bytes_per_chunk) ||
+                  tags.seq_number != bi->seq_number) {
+               yaffs_trace(YAFFS_TRACE_SCAN,
+                       "Chunk (%d:%d) with bad tags:obj = %d, chunk_id = %d, n_bytes = %d, ignored",
+                       blk, chunk_in_block, tags.obj_id,
+                       tags.chunk_id, tags.n_bytes);
+               dev->n_free_chunks++;
+       } else if (tags.chunk_id > 0) {
+               /* chunk_id > 0 so it is a data chunk... */
+               loff_t endpos;
+               loff_t chunk_base = (tags.chunk_id - 1) *
+                                       dev->data_bytes_per_chunk;
+
+               *found_chunks = 1;
+
+               yaffs_set_chunk_bit(dev, blk, chunk_in_block);
+               bi->pages_in_use++;
+
+               in = yaffs_find_or_create_by_number(dev,
+                                       tags.obj_id,
+                                       YAFFS_OBJECT_TYPE_FILE);
+               if (!in)
+                       /* Out of memory */
+                       alloc_failed = 1;
+
+               if (in &&
+                   in->variant_type == YAFFS_OBJECT_TYPE_FILE &&
+                   chunk_base < in->variant.file_variant.shrink_size) {
+                       /* This has not been invalidated by
+                        * a resize */
+                       if (!yaffs_put_chunk_in_file(in, tags.chunk_id,
+                                                               chunk, -1))
+                               alloc_failed = 1;
+
+                       /* File size is calculated by looking at
+                        * the data chunks if we have not
+                        * seen an object header yet.
+                        * Stop this practice once we find an
+                        * object header.
+                        */
+                       endpos = chunk_base + tags.n_bytes;
+
+                       if (!in->valid &&
+                           in->variant.file_variant.scanned_size < endpos) {
+                               in->variant.file_variant.
+                                   scanned_size = endpos;
+                               in->variant.file_variant.
+                                   file_size = endpos;
+                       }
+               } else if (in) {
+                       /* This chunk has been invalidated by a
+                        * resize, or a past file deletion
+                        * so delete the chunk*/
+                       yaffs_chunk_del(dev, chunk, 1, __LINE__);
+               }
+       } else {
+               /* chunk_id == 0, so it is an ObjectHeader.
+                * Thus, we read in the object header and make
+                * the object
+                */
+               *found_chunks = 1;
+
+               yaffs_set_chunk_bit(dev, blk, chunk_in_block);
+               bi->pages_in_use++;
+
+               oh = NULL;
+               in = NULL;
+
+               if (tags.extra_available) {
+                       in = yaffs_find_or_create_by_number(dev,
+                                       tags.obj_id,
+                                       tags.extra_obj_type);
+                       if (!in)
+                               alloc_failed = 1;
+               }
+
+               if (!in ||
+                   (!in->valid && dev->param.disable_lazy_load) ||
+                   tags.extra_shadows ||
+                   (!in->valid && (tags.obj_id == YAFFS_OBJECTID_ROOT ||
+                                tags.obj_id == YAFFS_OBJECTID_LOSTNFOUND))) {
+
+                       /* If we don't have  valid info then we
+                        * need to read the chunk
+                        * TODO In future we can probably defer
+                        * reading the chunk and living with
+                        * invalid data until needed.
+                        */
+
+                       result = yaffs_rd_chunk_tags_nand(dev,
+                                                 chunk,
+                                                 chunk_data,
+                                                 NULL);
+
+                       oh = (struct yaffs_obj_hdr *)chunk_data;
+
+                       if (dev->param.inband_tags) {
+                               /* Fix up the header if they got
+                                * corrupted by inband tags */
+                               oh->shadows_obj =
+                                   oh->inband_shadowed_obj_id;
+                               oh->is_shrink =
+                                   oh->inband_is_shrink;
+                       }
+
+                       if (!in) {
+                               in = yaffs_find_or_create_by_number(dev,
+                                                       tags.obj_id, oh->type);
+                               if (!in)
+                                       alloc_failed = 1;
+                       }
+               }
+
+               if (!in) {
+                       /* TODO Hoosterman we have a problem! */
+                       yaffs_trace(YAFFS_TRACE_ERROR,
+                               "yaffs tragedy: Could not make object for object  %d at chunk %d during scan",
+                               tags.obj_id, chunk);
+                       return YAFFS_FAIL;
+               }
+
+               if (in->valid) {
+                       /* We have already filled this one.
+                        * We have a duplicate that will be
+                        * discarded, but we first have to suck
+                        * out resize info if it is a file.
+                        */
+                       if ((in->variant_type == YAFFS_OBJECT_TYPE_FILE) &&
+                               ((oh && oh->type == YAFFS_OBJECT_TYPE_FILE) ||
+                                (tags.extra_available &&
+                                 tags.extra_obj_type == YAFFS_OBJECT_TYPE_FILE)
+                               )) {
+                               loff_t this_size = (oh) ?
+                                       yaffs_oh_to_size(oh) :
+                                       tags.extra_file_size;
+                               u32 parent_obj_id = (oh) ?
+                                       oh->parent_obj_id :
+                                       tags.extra_parent_id;
+
+                               is_shrink = (oh) ?
+                                       oh->is_shrink :
+                                       tags.extra_is_shrink;
+
+                               /* If it is deleted (unlinked
+                                * at start also means deleted)
+                                * we treat the file size as
+                                * being zeroed at this point.
+                                */
+                               if (parent_obj_id == YAFFS_OBJECTID_DELETED ||
+                                   parent_obj_id == YAFFS_OBJECTID_UNLINKED) {
+                                       this_size = 0;
+                                       is_shrink = 1;
+                               }
+
+                               if (is_shrink &&
+                                   in->variant.file_variant.shrink_size >
+                                   this_size)
+                                       in->variant.file_variant.shrink_size =
+                                       this_size;
+
+                               if (is_shrink)
+                                       bi->has_shrink_hdr = 1;
+                       }
+                       /* Use existing - destroy this one. */
+                       yaffs_chunk_del(dev, chunk, 1, __LINE__);
+               }
+
+               if (!in->valid && in->variant_type !=
+                   (oh ? oh->type : tags.extra_obj_type)) {
+                       yaffs_trace(YAFFS_TRACE_ERROR,
+                               "yaffs tragedy: Bad type, %d != %d, for object %d at chunk %d during scan",
+                               oh ? oh->type : tags.extra_obj_type,
+                               in->variant_type, tags.obj_id,
+                               chunk);
+                       in = yaffs_retype_obj(in, oh ? oh->type : tags.extra_obj_type);
+               }
+
+               if (!in->valid &&
+                   (tags.obj_id == YAFFS_OBJECTID_ROOT ||
+                    tags.obj_id == YAFFS_OBJECTID_LOSTNFOUND)) {
+                       /* We only load some info, don't fiddle
+                        * with directory structure */
+                       in->valid = 1;
+
+                       if (oh) {
+                               in->yst_mode = oh->yst_mode;
+                               yaffs_load_attribs(in, oh);
+                               in->lazy_loaded = 0;
+                       } else {
+                               in->lazy_loaded = 1;
+                       }
+                       in->hdr_chunk = chunk;
+
+               } else if (!in->valid) {
+                       /* we need to load this info */
+                       in->valid = 1;
+                       in->hdr_chunk = chunk;
+                       if (oh) {
+                               in->variant_type = oh->type;
+                               in->yst_mode = oh->yst_mode;
+                               yaffs_load_attribs(in, oh);
+
+                               if (oh->shadows_obj > 0)
+                                       yaffs_handle_shadowed_obj(dev,
+                                            oh->shadows_obj, 1);
+
+                               yaffs_set_obj_name_from_oh(in, oh);
+                               parent = yaffs_find_or_create_by_number(dev,
+                                               oh->parent_obj_id,
+                                               YAFFS_OBJECT_TYPE_DIRECTORY);
+                               file_size = yaffs_oh_to_size(oh);
+                               is_shrink = oh->is_shrink;
+                               equiv_id = oh->equiv_id;
+                       } else {
+                               in->variant_type = tags.extra_obj_type;
+                               parent = yaffs_find_or_create_by_number(dev,
+                                               tags.extra_parent_id,
+                                               YAFFS_OBJECT_TYPE_DIRECTORY);
+                               file_size = tags.extra_file_size;
+                               is_shrink = tags.extra_is_shrink;
+                               equiv_id = tags.extra_equiv_id;
+                               in->lazy_loaded = 1;
+                       }
+                       in->dirty = 0;
+
+                       if (!parent)
+                               alloc_failed = 1;
+
+                       /* directory stuff...
+                        * hook up to parent
+                        */
+
+                       if (parent &&
+                           parent->variant_type == YAFFS_OBJECT_TYPE_UNKNOWN) {
+                               /* Set up as a directory */
+                               parent->variant_type =
+                                       YAFFS_OBJECT_TYPE_DIRECTORY;
+                               INIT_LIST_HEAD(&parent->
+                                               variant.dir_variant.children);
+                       } else if (!parent ||
+                                  parent->variant_type !=
+                                       YAFFS_OBJECT_TYPE_DIRECTORY) {
+                               /* Hoosterman, another problem....
+                                * Trying to use a non-directory as a directory
+                                */
+
+                               yaffs_trace(YAFFS_TRACE_ERROR,
+                                       "yaffs tragedy: attempting to use non-directory as a directory in scan. Put in lost+found."
+                                       );
+                               parent = dev->lost_n_found;
+                       }
+                       yaffs_add_obj_to_dir(parent, in);
+
+                       is_unlinked = (parent == dev->del_dir) ||
+                                       (parent == dev->unlinked_dir);
+
+                       if (is_shrink)
+                               /* Mark the block */
+                               bi->has_shrink_hdr = 1;
+
+                       /* Note re hardlinks.
+                        * Since we might scan a hardlink before its equivalent
+                        * object is scanned we put them all in a list.
+                        * After scanning is complete, we should have all the
+                        * objects, so we run through this list and fix up all
+                        * the chains.
+                        */
+
+                       switch (in->variant_type) {
+                       case YAFFS_OBJECT_TYPE_UNKNOWN:
+                               /* Todo got a problem */
+                               break;
+                       case YAFFS_OBJECT_TYPE_FILE:
+                               file_var = &in->variant.file_variant;
+                               if (file_var->scanned_size < file_size) {
+                                       /* This covers the case where the file
+                                        * size is greater than the data held.
+                                        * This will happen if the file is
+                                        * resized to be larger than its
+                                        * current data extents.
+                                        */
+                                       file_var->file_size = file_size;
+                                       file_var->scanned_size = file_size;
+                               }
+
+                               if (file_var->shrink_size > file_size)
+                                       file_var->shrink_size = file_size;
+
+                               break;
+                       case YAFFS_OBJECT_TYPE_HARDLINK:
+                               hl_var = &in->variant.hardlink_variant;
+                               if (!is_unlinked) {
+                                       hl_var->equiv_id = equiv_id;
+                                       list_add(&in->hard_links, hard_list);
+                               }
+                               break;
+                       case YAFFS_OBJECT_TYPE_DIRECTORY:
+                               /* Do nothing */
+                               break;
+                       case YAFFS_OBJECT_TYPE_SPECIAL:
+                               /* Do nothing */
+                               break;
+                       case YAFFS_OBJECT_TYPE_SYMLINK:
+                               sl_var = &in->variant.symlink_variant;
+                               if (oh) {
+                                       sl_var->alias =
+                                           yaffs_clone_str(oh->alias);
+                                       if (!sl_var->alias)
+                                               alloc_failed = 1;
+                               }
+                               break;
+                       }
+               }
+       }
+       return alloc_failed ? YAFFS_FAIL : YAFFS_OK;
+}
+
+int yaffs2_scan_backwards(struct yaffs_dev *dev)
+{
        int blk;
        int block_iter;
        int start_iter;
        int end_iter;
        int n_to_scan = 0;
-
-       int chunk;
-       int result;
+       enum yaffs_block_state state;
        int c;
        int deleted;
-       enum yaffs_block_state state;
-       struct yaffs_obj *hard_list = NULL;
+       LIST_HEAD(hard_list);
        struct yaffs_block_info *bi;
        u32 seq_number;
-       struct yaffs_obj_hdr *oh;
-       struct yaffs_obj *in;
-       struct yaffs_obj *parent;
        int n_blocks = dev->internal_end_block - dev->internal_start_block + 1;
-       int is_unlinked;
        u8 *chunk_data;
-
-       int file_size;
-       int is_shrink;
        int found_chunks;
-       int equiv_id;
        int alloc_failed = 0;
-
        struct yaffs_block_index *block_index = NULL;
        int alt_block_index = 0;
+       int summary_available;
 
-       T(YAFFS_TRACE_SCAN,
-         (TSTR
-          ("yaffs2_scan_backwards starts  intstartblk %d intendblk %d..."
-           TENDSTR), dev->internal_start_block, dev->internal_end_block));
+       yaffs_trace(YAFFS_TRACE_SCAN,
+               "yaffs2_scan_backwards starts  intstartblk %d intendblk %d...",
+               dev->internal_start_block, dev->internal_end_block);
 
        dev->seq_number = YAFFS_LOWEST_SEQUENCE_NUMBER;
 
-       block_index = YMALLOC(n_blocks * sizeof(struct yaffs_block_index));
+       block_index =
+               kmalloc(n_blocks * sizeof(struct yaffs_block_index), GFP_NOFS);
 
        if (!block_index) {
                block_index =
-                   YMALLOC_ALT(n_blocks * sizeof(struct yaffs_block_index));
+                   vmalloc(n_blocks * sizeof(struct yaffs_block_index));
                alt_block_index = 1;
        }
 
        if (!block_index) {
-               T(YAFFS_TRACE_SCAN,
-                 (TSTR
-                  ("yaffs2_scan_backwards() could not allocate block index!"
-                   TENDSTR)));
+               yaffs_trace(YAFFS_TRACE_SCAN,
+                       "yaffs2_scan_backwards() could not allocate block index!"
+                       );
                return YAFFS_FAIL;
        }
 
        dev->blocks_in_checkpt = 0;
 
-       chunk_data = yaffs_get_temp_buffer(dev, __LINE__);
+       chunk_data = yaffs_get_temp_buffer(dev);
 
        /* Scan all the blocks to determine their state */
        bi = dev->block_info;
@@ -1035,556 +1403,103 @@ int yaffs2_scan_backwards(struct yaffs_dev *dev)
                bi->seq_number = seq_number;
 
                if (bi->seq_number == YAFFS_SEQUENCE_CHECKPOINT_DATA)
-                       bi->block_state = state = YAFFS_BLOCK_STATE_CHECKPOINT;
+                       bi->block_state = YAFFS_BLOCK_STATE_CHECKPOINT;
                if (bi->seq_number == YAFFS_SEQUENCE_BAD_BLOCK)
-                       bi->block_state = state = YAFFS_BLOCK_STATE_DEAD;
+                       bi->block_state = YAFFS_BLOCK_STATE_DEAD;
 
-               T(YAFFS_TRACE_SCAN_DEBUG,
-                 (TSTR("Block scanning block %d state %d seq %d" TENDSTR), blk,
-                  state, seq_number));
+               yaffs_trace(YAFFS_TRACE_SCAN_DEBUG,
+                       "Block scanning block %d state %d seq %d",
+                       blk, bi->block_state, seq_number);
 
-               if (state == YAFFS_BLOCK_STATE_CHECKPOINT) {
+               if (bi->block_state == YAFFS_BLOCK_STATE_CHECKPOINT) {
                        dev->blocks_in_checkpt++;
 
-               } else if (state == YAFFS_BLOCK_STATE_DEAD) {
-                       T(YAFFS_TRACE_BAD_BLOCKS,
-                         (TSTR("block %d is bad" TENDSTR), blk));
-               } else if (state == YAFFS_BLOCK_STATE_EMPTY) {
-                       T(YAFFS_TRACE_SCAN_DEBUG,
-                         (TSTR("Block empty " TENDSTR)));
+               } else if (bi->block_state == YAFFS_BLOCK_STATE_DEAD) {
+                       yaffs_trace(YAFFS_TRACE_BAD_BLOCKS,
+                               "block %d is bad", blk);
+               } else if (bi->block_state == YAFFS_BLOCK_STATE_EMPTY) {
+                       yaffs_trace(YAFFS_TRACE_SCAN_DEBUG, "Block empty ");
                        dev->n_erased_blocks++;
                        dev->n_free_chunks += dev->param.chunks_per_block;
-               } else if (state == YAFFS_BLOCK_STATE_NEEDS_SCANNING) {
-
+               } else if (bi->block_state ==
+                               YAFFS_BLOCK_STATE_NEEDS_SCAN) {
                        /* Determine the highest sequence number */
                        if (seq_number >= YAFFS_LOWEST_SEQUENCE_NUMBER &&
                            seq_number < YAFFS_HIGHEST_SEQUENCE_NUMBER) {
-
                                block_index[n_to_scan].seq = seq_number;
                                block_index[n_to_scan].block = blk;
-
                                n_to_scan++;
-
                                if (seq_number >= dev->seq_number)
                                        dev->seq_number = seq_number;
                        } else {
                                /* TODO: Nasty sequence number! */
-                               T(YAFFS_TRACE_SCAN,
-                                 (TSTR
-                                  ("Block scanning block %d has bad sequence number %d"
-                                   TENDSTR), blk, seq_number));
-
+                               yaffs_trace(YAFFS_TRACE_SCAN,
+                                       "Block scanning block %d has bad sequence number %d",
+                                       blk, seq_number);
                        }
                }
                bi++;
        }
 
-       T(YAFFS_TRACE_SCAN,
-         (TSTR("%d blocks to be sorted..." TENDSTR), n_to_scan));
+       yaffs_trace(YAFFS_TRACE_ALWAYS, "%d blocks to be sorted...", n_to_scan);
 
-       YYIELD();
+       cond_resched();
 
        /* Sort the blocks by sequence number */
-       yaffs_sort(block_index, n_to_scan, sizeof(struct yaffs_block_index),
-                  yaffs2_ybicmp);
+       sort(block_index, n_to_scan, sizeof(struct yaffs_block_index),
+                  yaffs2_ybicmp, NULL);
 
-       YYIELD();
+       cond_resched();
 
-       T(YAFFS_TRACE_SCAN, (TSTR("...done" TENDSTR)));
+       yaffs_trace(YAFFS_TRACE_SCAN, "...done");
 
        /* Now scan the blocks looking at the data. */
        start_iter = 0;
        end_iter = n_to_scan - 1;
-       T(YAFFS_TRACE_SCAN_DEBUG,
-         (TSTR("%d blocks to be scanned" TENDSTR), n_to_scan));
+       yaffs_trace(YAFFS_TRACE_SCAN_DEBUG, "%d blocks to scan", n_to_scan);
 
        /* For each block.... backwards */
-       for (block_iter = end_iter; !alloc_failed && block_iter >= start_iter;
+       for (block_iter = end_iter;
+            !alloc_failed && block_iter >= start_iter;
             block_iter--) {
                /* Cooperative multitasking! This loop can run for so
                   long that watchdog timers expire. */
-               YYIELD();
+               cond_resched();
 
                /* get the block to scan in the correct order */
                blk = block_index[block_iter].block;
-
                bi = yaffs_get_block_info(dev, blk);
-
-               state = bi->block_state;
-
                deleted = 0;
 
+               summary_available = yaffs_summary_read(dev, dev->sum_tags, blk);
+
                /* For each chunk in each block that needs scanning.... */
                found_chunks = 0;
-               for (c = dev->param.chunks_per_block - 1;
+               if (summary_available)
+                       c = dev->chunks_per_summary - 1;
+               else
+                       c = dev->param.chunks_per_block - 1;
+
+               for (/* c is already initialised */;
                     !alloc_failed && c >= 0 &&
-                    (state == YAFFS_BLOCK_STATE_NEEDS_SCANNING ||
-                     state == YAFFS_BLOCK_STATE_ALLOCATING); c--) {
+                    (bi->block_state == YAFFS_BLOCK_STATE_NEEDS_SCAN ||
+                     bi->block_state == YAFFS_BLOCK_STATE_ALLOCATING);
+                     c--) {
                        /* Scan backwards...
                         * Read the tags and decide what to do
                         */
-
-                       chunk = blk * dev->param.chunks_per_block + c;
-
-                       result = yaffs_rd_chunk_tags_nand(dev, chunk, NULL,
-                                                         &tags);
-
-                       /* Let's have a good look at this chunk... */
-
-                       if (!tags.chunk_used) {
-                               /* An unassigned chunk in the block.
-                                * If there are used chunks after this one, then
-                                * it is a chunk that was skipped due to failing the erased
-                                * check. Just skip it so that it can be deleted.
-                                * But, more typically, We get here when this is an unallocated
-                                * chunk and his means that either the block is empty or
-                                * this is the one being allocated from
-                                */
-
-                               if (found_chunks) {
-                                       /* This is a chunk that was skipped due to failing the erased check */
-                               } else if (c == 0) {
-                                       /* We're looking at the first chunk in the block so the block is unused */
-                                       state = YAFFS_BLOCK_STATE_EMPTY;
-                                       dev->n_erased_blocks++;
-                               } else {
-                                       if (state ==
-                                           YAFFS_BLOCK_STATE_NEEDS_SCANNING
-                                           || state ==
-                                           YAFFS_BLOCK_STATE_ALLOCATING) {
-                                               if (dev->seq_number ==
-                                                   bi->seq_number) {
-                                                       /* this is the block being allocated from */
-
-                                                       T(YAFFS_TRACE_SCAN,
-                                                         (TSTR
-                                                          (" Allocating from %d %d"
-                                                           TENDSTR), blk, c));
-
-                                                       state =
-                                                           YAFFS_BLOCK_STATE_ALLOCATING;
-                                                       dev->alloc_block = blk;
-                                                       dev->alloc_page = c;
-                                                       dev->
-                                                           alloc_block_finder =
-                                                           blk;
-                                               } else {
-                                                       /* This is a partially written block that is not
-                                                        * the current allocation block.
-                                                        */
-
-                                                       T(YAFFS_TRACE_SCAN,
-                                                         (TSTR
-                                                          ("Partially written block %d detected"
-                                                           TENDSTR), blk));
-                                               }
-                                       }
-                               }
-
-                               dev->n_free_chunks++;
-
-                       } else if (tags.ecc_result == YAFFS_ECC_RESULT_UNFIXED) {
-                               T(YAFFS_TRACE_SCAN,
-                                 (TSTR
-                                  (" Unfixed ECC in chunk(%d:%d), chunk ignored"
-                                   TENDSTR), blk, c));
-
-                               dev->n_free_chunks++;
-
-                       } else if (tags.obj_id > YAFFS_MAX_OBJECT_ID ||
-                                  tags.chunk_id > YAFFS_MAX_CHUNK_ID ||
-                                  (tags.chunk_id > 0
-                                   && tags.n_bytes > dev->data_bytes_per_chunk)
-                                  || tags.seq_number != bi->seq_number) {
-                               T(YAFFS_TRACE_SCAN,
-                                 (TSTR
-                                  ("Chunk (%d:%d) with bad tags:obj = %d, chunk_id = %d, n_bytes = %d, ignored"
-                                   TENDSTR), blk, c, tags.obj_id,
-                                  tags.chunk_id, tags.n_bytes));
-
-                               dev->n_free_chunks++;
-
-                       } else if (tags.chunk_id > 0) {
-                               /* chunk_id > 0 so it is a data chunk... */
-                               unsigned int endpos;
-                               u32 chunk_base =
-                                   (tags.chunk_id -
-                                    1) * dev->data_bytes_per_chunk;
-
-                               found_chunks = 1;
-
-                               yaffs_set_chunk_bit(dev, blk, c);
-                               bi->pages_in_use++;
-
-                               in = yaffs_find_or_create_by_number(dev,
-                                                                   tags.obj_id,
-                                                                   YAFFS_OBJECT_TYPE_FILE);
-                               if (!in) {
-                                       /* Out of memory */
-                                       alloc_failed = 1;
-                               }
-
-                               if (in &&
-                                   in->variant_type == YAFFS_OBJECT_TYPE_FILE
-                                   && chunk_base <
-                                   in->variant.file_variant.shrink_size) {
-                                       /* This has not been invalidated by a resize */
-                                       if (!yaffs_put_chunk_in_file
-                                           (in, tags.chunk_id, chunk, -1)) {
-                                               alloc_failed = 1;
-                                       }
-
-                                       /* File size is calculated by looking at the data chunks if we have not
-                                        * seen an object header yet. Stop this practice once we find an object header.
-                                        */
-                                       endpos = chunk_base + tags.n_bytes;
-
-                                       if (!in->valid &&       /* have not got an object header yet */
-                                           in->variant.file_variant.
-                                           scanned_size < endpos) {
-                                               in->variant.file_variant.
-                                                   scanned_size = endpos;
-                                               in->variant.file_variant.
-                                                   file_size = endpos;
-                                       }
-
-                               } else if (in) {
-                                       /* This chunk has been invalidated by a resize, or a past file deletion
-                                        * so delete the chunk*/
-                                       yaffs_chunk_del(dev, chunk, 1,
-                                                       __LINE__);
-
-                               }
-                       } else {
-                               /* chunk_id == 0, so it is an ObjectHeader.
-                                * Thus, we read in the object header and make the object
-                                */
-                               found_chunks = 1;
-
-                               yaffs_set_chunk_bit(dev, blk, c);
-                               bi->pages_in_use++;
-
-                               oh = NULL;
-                               in = NULL;
-
-                               if (tags.extra_available) {
-                                       in = yaffs_find_or_create_by_number(dev,
-                                                                           tags.
-                                                                           obj_id,
-                                                                           tags.
-                                                                           extra_obj_type);
-                                       if (!in)
-                                               alloc_failed = 1;
-                               }
-
-                               if (!in ||
-                                   (!in->valid && dev->param.disable_lazy_load)
-                                   || tags.extra_shadows || (!in->valid
-                                                             && (tags.obj_id ==
-                                                                 YAFFS_OBJECTID_ROOT
-                                                                 || tags.
-                                                                 obj_id ==
-                                                                 YAFFS_OBJECTID_LOSTNFOUND)))
-                               {
-
-                                       /* If we don't have  valid info then we need to read the chunk
-                                        * TODO In future we can probably defer reading the chunk and
-                                        * living with invalid data until needed.
-                                        */
-
-                                       result = yaffs_rd_chunk_tags_nand(dev,
-                                                                         chunk,
-                                                                         chunk_data,
-                                                                         NULL);
-
-                                       oh = (struct yaffs_obj_hdr *)chunk_data;
-
-                                       if (dev->param.inband_tags) {
-                                               /* Fix up the header if they got corrupted by inband tags */
-                                               oh->shadows_obj =
-                                                   oh->inband_shadowed_obj_id;
-                                               oh->is_shrink =
-                                                   oh->inband_is_shrink;
-                                       }
-
-                                       if (!in) {
-                                               in = yaffs_find_or_create_by_number(dev, tags.obj_id, oh->type);
-                                               if (!in)
-                                                       alloc_failed = 1;
-                                       }
-
-                               }
-
-                               if (!in) {
-                                       /* TODO Hoosterman we have a problem! */
-                                       T(YAFFS_TRACE_ERROR,
-                                         (TSTR
-                                          ("yaffs tragedy: Could not make object for object  %d at chunk %d during scan"
-                                           TENDSTR), tags.obj_id, chunk));
-                                       continue;
-                               }
-
-                               if (in->valid) {
-                                       /* We have already filled this one.
-                                        * We have a duplicate that will be discarded, but
-                                        * we first have to suck out resize info if it is a file.
-                                        */
-
-                                       if ((in->variant_type ==
-                                            YAFFS_OBJECT_TYPE_FILE) && ((oh
-                                                                         &&
-                                                                         oh->
-                                                                         type
-                                                                         ==
-                                                                         YAFFS_OBJECT_TYPE_FILE)
-                                                                        ||
-                                                                        (tags.
-                                                                         extra_available
-                                                                         &&
-                                                                         tags.
-                                                                         extra_obj_type
-                                                                         ==
-                                                                         YAFFS_OBJECT_TYPE_FILE)))
-                                       {
-                                               u32 this_size =
-                                                   (oh) ? oh->
-                                                   file_size :
-                                                   tags.extra_length;
-                                               u32 parent_obj_id =
-                                                   (oh) ? oh->parent_obj_id :
-                                                   tags.extra_parent_id;
-
-                                               is_shrink =
-                                                   (oh) ? oh->
-                                                   is_shrink :
-                                                   tags.extra_is_shrink;
-
-                                               /* If it is deleted (unlinked at start also means deleted)
-                                                * we treat the file size as being zeroed at this point.
-                                                */
-                                               if (parent_obj_id ==
-                                                   YAFFS_OBJECTID_DELETED
-                                                   || parent_obj_id ==
-                                                   YAFFS_OBJECTID_UNLINKED) {
-                                                       this_size = 0;
-                                                       is_shrink = 1;
-                                               }
-
-                                               if (is_shrink
-                                                   && in->variant.file_variant.
-                                                   shrink_size > this_size)
-                                                       in->variant.
-                                                           file_variant.
-                                                           shrink_size =
-                                                           this_size;
-
-                                               if (is_shrink)
-                                                       bi->has_shrink_hdr = 1;
-
-                                       }
-                                       /* Use existing - destroy this one. */
-                                       yaffs_chunk_del(dev, chunk, 1,
-                                                       __LINE__);
-
-                               }
-
-                               if (!in->valid && in->variant_type !=
-                                   (oh ? oh->type : tags.extra_obj_type))
-                                       T(YAFFS_TRACE_ERROR,
-                                         (TSTR
-                                          ("yaffs tragedy: Bad object type, "
-                                           TCONT
-                                           ("%d != %d, for object %d at chunk ")
-                                           TCONT("%d during scan")
-                                           TENDSTR), oh ?
-                                          oh->type : tags.extra_obj_type,
-                                          in->variant_type, tags.obj_id,
-                                          chunk));
-
-                               if (!in->valid &&
-                                   (tags.obj_id == YAFFS_OBJECTID_ROOT ||
-                                    tags.obj_id ==
-                                    YAFFS_OBJECTID_LOSTNFOUND)) {
-                                       /* We only load some info, don't fiddle with directory structure */
-                                       in->valid = 1;
-
-                                       if (oh) {
-
-                                               in->yst_mode = oh->yst_mode;
-                                               yaffs_load_attribs(in, oh);
-                                               in->lazy_loaded = 0;
-                                       } else {
-                                               in->lazy_loaded = 1;
-                                        }
-                                       in->hdr_chunk = chunk;
-
-                               } else if (!in->valid) {
-                                       /* we need to load this info */
-
-                                       in->valid = 1;
-                                       in->hdr_chunk = chunk;
-
-                                       if (oh) {
-                                               in->variant_type = oh->type;
-
-                                               in->yst_mode = oh->yst_mode;
-                                               yaffs_load_attribs(in, oh);
-
-                                               if (oh->shadows_obj > 0)
-                                                       yaffs_handle_shadowed_obj
-                                                           (dev,
-                                                            oh->shadows_obj,
-                                                            1);
-
-                                               yaffs_set_obj_name_from_oh(in,
-                                                                          oh);
-                                               parent =
-                                                   yaffs_find_or_create_by_number
-                                                   (dev, oh->parent_obj_id,
-                                                    YAFFS_OBJECT_TYPE_DIRECTORY);
-
-                                               file_size = oh->file_size;
-                                               is_shrink = oh->is_shrink;
-                                               equiv_id = oh->equiv_id;
-
-                                       } else {
-                                               in->variant_type =
-                                                   tags.extra_obj_type;
-                                               parent =
-                                                   yaffs_find_or_create_by_number
-                                                   (dev, tags.extra_parent_id,
-                                                    YAFFS_OBJECT_TYPE_DIRECTORY);
-                                               file_size = tags.extra_length;
-                                               is_shrink =
-                                                   tags.extra_is_shrink;
-                                               equiv_id = tags.extra_equiv_id;
-                                               in->lazy_loaded = 1;
-
-                                       }
-                                       in->dirty = 0;
-
-                                       if (!parent)
-                                               alloc_failed = 1;
-
-                                       /* directory stuff...
-                                        * hook up to parent
-                                        */
-
-                                       if (parent && parent->variant_type ==
-                                           YAFFS_OBJECT_TYPE_UNKNOWN) {
-                                               /* Set up as a directory */
-                                               parent->variant_type =
-                                                   YAFFS_OBJECT_TYPE_DIRECTORY;
-                                               INIT_LIST_HEAD(&parent->
-                                                              variant.dir_variant.children);
-                                       } else if (!parent
-                                                  || parent->variant_type !=
-                                                  YAFFS_OBJECT_TYPE_DIRECTORY) {
-                                               /* Hoosterman, another problem....
-                                                * We're trying to use a non-directory as a directory
-                                                */
-
-                                               T(YAFFS_TRACE_ERROR,
-                                                 (TSTR
-                                                  ("yaffs tragedy: attempting to use non-directory as a directory in scan. Put in lost+found."
-                                                   TENDSTR)));
-                                               parent = dev->lost_n_found;
-                                       }
-
-                                       yaffs_add_obj_to_dir(parent, in);
-
-                                       is_unlinked = (parent == dev->del_dir)
-                                           || (parent == dev->unlinked_dir);
-
-                                       if (is_shrink) {
-                                               /* Mark the block as having a shrink header */
-                                               bi->has_shrink_hdr = 1;
-                                       }
-
-                                       /* Note re hardlinks.
-                                        * Since we might scan a hardlink before its equivalent object is scanned
-                                        * we put them all in a list.
-                                        * After scanning is complete, we should have all the objects, so we run
-                                        * through this list and fix up all the chains.
-                                        */
-
-                                       switch (in->variant_type) {
-                                       case YAFFS_OBJECT_TYPE_UNKNOWN:
-                                               /* Todo got a problem */
-                                               break;
-                                       case YAFFS_OBJECT_TYPE_FILE:
-
-                                               if (in->variant.
-                                                   file_variant.scanned_size <
-                                                   file_size) {
-                                                       /* This covers the case where the file size is greater
-                                                        * than where the data is
-                                                        * This will happen if the file is resized to be larger
-                                                        * than its current data extents.
-                                                        */
-                                                       in->variant.
-                                                           file_variant.
-                                                           file_size =
-                                                           file_size;
-                                                       in->variant.
-                                                           file_variant.
-                                                           scanned_size =
-                                                           file_size;
-                                               }
-
-                                               if (in->variant.file_variant.
-                                                   shrink_size > file_size)
-                                                       in->variant.
-                                                           file_variant.
-                                                           shrink_size =
-                                                           file_size;
-
-                                               break;
-                                       case YAFFS_OBJECT_TYPE_HARDLINK:
-                                               if (!is_unlinked) {
-                                                       in->variant.
-                                                           hardlink_variant.
-                                                           equiv_id = equiv_id;
-                                                       in->hard_links.next =
-                                                           (struct list_head *)
-                                                           hard_list;
-                                                       hard_list = in;
-                                               }
-                                               break;
-                                       case YAFFS_OBJECT_TYPE_DIRECTORY:
-                                               /* Do nothing */
-                                               break;
-                                       case YAFFS_OBJECT_TYPE_SPECIAL:
-                                               /* Do nothing */
-                                               break;
-                                       case YAFFS_OBJECT_TYPE_SYMLINK:
-                                               if (oh) {
-                                                       in->variant.
-                                                           symlink_variant.
-                                                           alias =
-                                                           yaffs_clone_str(oh->
-                                                                           alias);
-                                                       if (!in->variant.
-                                                           symlink_variant.
-                                                           alias)
-                                                               alloc_failed =
-                                                                   1;
-                                               }
-                                               break;
-                                       }
-
-                               }
-
-                       }
-
-               }               /* End of scanning for each chunk */
-
-               if (state == YAFFS_BLOCK_STATE_NEEDS_SCANNING) {
-                       /* If we got this far while scanning, then the block is fully allocated. */
-                       state = YAFFS_BLOCK_STATE_FULL;
+                       if (yaffs2_scan_chunk(dev, bi, blk, c,
+                                       &found_chunks, chunk_data,
+                                       &hard_list, summary_available) ==
+                                       YAFFS_FAIL)
+                               alloc_failed = 1;
                }
 
-               bi->block_state = state;
+               if (bi->block_state == YAFFS_BLOCK_STATE_NEEDS_SCAN) {
+                       /* If we got this far while scanning, then the block
+                        * is fully allocated. */
+                       bi->block_state = YAFFS_BLOCK_STATE_FULL;
+               }
 
                /* Now let's see if it was dirty */
                if (bi->pages_in_use == 0 &&
@@ -1592,29 +1507,28 @@ int yaffs2_scan_backwards(struct yaffs_dev *dev)
                    bi->block_state == YAFFS_BLOCK_STATE_FULL) {
                        yaffs_block_became_dirty(dev, blk);
                }
-
        }
 
        yaffs_skip_rest_of_block(dev);
 
        if (alt_block_index)
-               YFREE_ALT(block_index);
+               vfree(block_index);
        else
-               YFREE(block_index);
+               kfree(block_index);
 
        /* Ok, we've done all the scanning.
         * Fix up the hard link chains.
-        * We should now have scanned all the objects, now it's time to add these
+        * We have scanned all the objects, now it's time to add these
         * hardlinks.
         */
-       yaffs_link_fixup(dev, hard_list);
+       yaffs_link_fixup(dev, &hard_list);
 
-       yaffs_release_temp_buffer(dev, chunk_data, __LINE__);
+       yaffs_release_temp_buffer(dev, chunk_data);
 
        if (alloc_failed)
                return YAFFS_FAIL;
 
-       T(YAFFS_TRACE_SCAN, (TSTR("yaffs2_scan_backwards ends" TENDSTR)));
+       yaffs_trace(YAFFS_TRACE_SCAN, "yaffs2_scan_backwards ends");
 
        return YAFFS_OK;
 }