+ struct yaffs_tnode *tn;
+ struct yaffs_dev *dev = in->my_dev;
+ int existing_cunk;
+ struct yaffs_ext_tags existing_tags;
+ struct yaffs_ext_tags new_tags;
+ unsigned existing_serial, new_serial;
+
+ if (in->variant_type != YAFFS_OBJECT_TYPE_FILE) {
+ /* Just ignore an attempt at putting a chunk into a non-file during scanning
+ * If it is not during Scanning then something went wrong!
+ */
+ if (!in_scan) {
+ yaffs_trace(YAFFS_TRACE_ERROR,
+ "yaffs tragedy:attempt to put data chunk into a non-file"
+ );
+ YBUG();
+ }
+
+ yaffs_chunk_del(dev, nand_chunk, 1, __LINE__);
+ return YAFFS_OK;
+ }
+
+ tn = yaffs_add_find_tnode_0(dev,
+ &in->variant.file_variant,
+ inode_chunk, NULL);
+ if (!tn)
+ return YAFFS_FAIL;
+
+ if (!nand_chunk)
+ /* Dummy insert, bail now */
+ return YAFFS_OK;
+
+ existing_cunk = yaffs_get_group_base(dev, tn, inode_chunk);
+
+ if (in_scan != 0) {
+ /* If we're scanning then we need to test for duplicates
+ * NB This does not need to be efficient since it should only ever
+ * happen when the power fails during a write, then only one
+ * chunk should ever be affected.
+ *
+ * Correction for YAFFS2: This could happen quite a lot and we need to think about efficiency! TODO
+ * Update: For backward scanning we don't need to re-read tags so this is quite cheap.
+ */
+
+ if (existing_cunk > 0) {
+ /* NB Right now existing chunk will not be real chunk_id if the chunk group size > 1
+ * thus we have to do a FindChunkInFile to get the real chunk id.
+ *
+ * We have a duplicate now we need to decide which one to use:
+ *
+ * Backwards scanning YAFFS2: The old one is what we use, dump the new one.
+ * Forward scanning YAFFS2: The new one is what we use, dump the old one.
+ * YAFFS1: Get both sets of tags and compare serial numbers.
+ */
+
+ if (in_scan > 0) {
+ /* Only do this for forward scanning */
+ yaffs_rd_chunk_tags_nand(dev,
+ nand_chunk,
+ NULL, &new_tags);
+
+ /* Do a proper find */
+ existing_cunk =
+ yaffs_find_chunk_in_file(in, inode_chunk,
+ &existing_tags);
+ }
+
+ if (existing_cunk <= 0) {
+ /*Hoosterman - how did this happen? */
+
+ yaffs_trace(YAFFS_TRACE_ERROR,
+ "yaffs tragedy: existing chunk < 0 in scan"
+ );
+
+ }
+
+ /* NB The deleted flags should be false, otherwise the chunks will
+ * not be loaded during a scan
+ */
+
+ if (in_scan > 0) {
+ new_serial = new_tags.serial_number;
+ existing_serial = existing_tags.serial_number;
+ }
+
+ if ((in_scan > 0) &&
+ (existing_cunk <= 0 ||
+ ((existing_serial + 1) & 3) == new_serial)) {
+ /* Forward scanning.
+ * Use new
+ * Delete the old one and drop through to update the tnode
+ */
+ yaffs_chunk_del(dev, existing_cunk, 1,
+ __LINE__);
+ } else {
+ /* Backward scanning or we want to use the existing one
+ * Use existing.
+ * Delete the new one and return early so that the tnode isn't changed
+ */
+ yaffs_chunk_del(dev, nand_chunk, 1, __LINE__);
+ return YAFFS_OK;
+ }
+ }
+
+ }
+
+ if (existing_cunk == 0)
+ in->n_data_chunks++;
+
+ yaffs_load_tnode_0(dev, tn, inode_chunk, nand_chunk);
+
+ return YAFFS_OK;
+}
+
+static void yaffs_soft_del_chunk(struct yaffs_dev *dev, int chunk)
+{
+ struct yaffs_block_info *the_block;
+ unsigned block_no;
+
+ yaffs_trace(YAFFS_TRACE_DELETION, "soft delete chunk %d", chunk);
+
+ block_no = chunk / dev->param.chunks_per_block;
+ the_block = yaffs_get_block_info(dev, block_no);
+ if (the_block) {
+ the_block->soft_del_pages++;
+ dev->n_free_chunks++;
+ yaffs2_update_oldest_dirty_seq(dev, block_no, the_block);
+ }
+}
+
+/* SoftDeleteWorker scans backwards through the tnode tree and soft deletes all the chunks in the file.
+ * All soft deleting does is increment the block's softdelete count and pulls the chunk out
+ * of the tnode.
+ * Thus, essentially this is the same as DeleteWorker except that the chunks are soft deleted.
+ */
+
+static int yaffs_soft_del_worker(struct yaffs_obj *in, struct yaffs_tnode *tn,
+ u32 level, int chunk_offset)
+{
+ int i;
+ int the_chunk;
+ int all_done = 1;
+ struct yaffs_dev *dev = in->my_dev;
+
+ if (tn) {
+ if (level > 0) {
+
+ for (i = YAFFS_NTNODES_INTERNAL - 1; all_done && i >= 0;
+ i--) {
+ if (tn->internal[i]) {
+ all_done =
+ yaffs_soft_del_worker(in,
+ tn->internal
+ [i],
+ level - 1,
+ (chunk_offset
+ <<
+ YAFFS_TNODES_INTERNAL_BITS)
+ + i);
+ if (all_done) {
+ yaffs_free_tnode(dev,
+ tn->internal
+ [i]);
+ tn->internal[i] = NULL;
+ } else {
+ /* Hoosterman... how could this happen? */
+ }
+ }
+ }
+ return (all_done) ? 1 : 0;
+ } else if (level == 0) {
+
+ for (i = YAFFS_NTNODES_LEVEL0 - 1; i >= 0; i--) {
+ the_chunk = yaffs_get_group_base(dev, tn, i);
+ if (the_chunk) {
+ /* Note this does not find the real chunk, only the chunk group.
+ * We make an assumption that a chunk group is not larger than
+ * a block.
+ */
+ yaffs_soft_del_chunk(dev, the_chunk);
+ yaffs_load_tnode_0(dev, tn, i, 0);
+ }
+
+ }
+ return 1;
+
+ }
+
+ }
+
+ return 1;
+
+}
+
+static void yaffs_remove_obj_from_dir(struct yaffs_obj *obj)
+{
+ struct yaffs_dev *dev = obj->my_dev;
+ struct yaffs_obj *parent;
+
+ yaffs_verify_obj_in_dir(obj);
+ parent = obj->parent;
+
+ yaffs_verify_dir(parent);
+
+ if (dev && dev->param.remove_obj_fn)
+ dev->param.remove_obj_fn(obj);
+
+ list_del_init(&obj->siblings);
+ obj->parent = NULL;
+
+ yaffs_verify_dir(parent);
+}
+
+void yaffs_add_obj_to_dir(struct yaffs_obj *directory, struct yaffs_obj *obj)
+{
+ if (!directory) {
+ yaffs_trace(YAFFS_TRACE_ALWAYS,
+ "tragedy: Trying to add an object to a null pointer directory"
+ );
+ YBUG();
+ return;
+ }
+ if (directory->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY) {
+ yaffs_trace(YAFFS_TRACE_ALWAYS,
+ "tragedy: Trying to add an object to a non-directory"
+ );
+ YBUG();
+ }
+
+ if (obj->siblings.prev == NULL) {
+ /* Not initialised */
+ YBUG();
+ }
+
+ yaffs_verify_dir(directory);
+
+ yaffs_remove_obj_from_dir(obj);
+
+ /* Now add it */
+ list_add(&obj->siblings, &directory->variant.dir_variant.children);
+ obj->parent = directory;
+
+ if (directory == obj->my_dev->unlinked_dir
+ || directory == obj->my_dev->del_dir) {
+ obj->unlinked = 1;
+ obj->my_dev->n_unlinked_files++;
+ obj->rename_allowed = 0;
+ }
+
+ yaffs_verify_dir(directory);
+ yaffs_verify_obj_in_dir(obj);
+}
+
+static int yaffs_change_obj_name(struct yaffs_obj *obj,
+ struct yaffs_obj *new_dir,
+ const YCHAR * new_name, int force, int shadows)
+{
+ int unlink_op;
+ int del_op;
+
+ struct yaffs_obj *existing_target;
+
+ if (new_dir == NULL)
+ new_dir = obj->parent; /* use the old directory */
+
+ if (new_dir->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY) {
+ yaffs_trace(YAFFS_TRACE_ALWAYS,
+ "tragedy: yaffs_change_obj_name: new_dir is not a directory"
+ );
+ YBUG();
+ }
+
+ /* TODO: Do we need this different handling for YAFFS2 and YAFFS1?? */
+ if (obj->my_dev->param.is_yaffs2)
+ unlink_op = (new_dir == obj->my_dev->unlinked_dir);
+ else
+ unlink_op = (new_dir == obj->my_dev->unlinked_dir
+ && obj->variant_type == YAFFS_OBJECT_TYPE_FILE);
+
+ del_op = (new_dir == obj->my_dev->del_dir);
+
+ existing_target = yaffs_find_by_name(new_dir, new_name);
+
+ /* If the object is a file going into the unlinked directory,
+ * then it is OK to just stuff it in since duplicate names are allowed.
+ * else only proceed if the new name does not exist and if we're putting
+ * it into a directory.
+ */
+ if ((unlink_op ||
+ del_op ||
+ force ||
+ (shadows > 0) ||
+ !existing_target) &&
+ new_dir->variant_type == YAFFS_OBJECT_TYPE_DIRECTORY) {
+ yaffs_set_obj_name(obj, new_name);
+ obj->dirty = 1;
+
+ yaffs_add_obj_to_dir(new_dir, obj);
+
+ if (unlink_op)
+ obj->unlinked = 1;
+
+ /* If it is a deletion then we mark it as a shrink for gc purposes. */
+ if (yaffs_update_oh(obj, new_name, 0, del_op, shadows, NULL) >=
+ 0)
+ return YAFFS_OK;
+ }
+
+ return YAFFS_FAIL;
+}
+
+/*------------------------ Short Operations Cache ----------------------------------------
+ * In many situations where there is no high level buffering a lot of
+ * reads might be short sequential reads, and a lot of writes may be short
+ * sequential writes. eg. scanning/writing a jpeg file.
+ * In these cases, a short read/write cache can provide a huge perfomance
+ * benefit with dumb-as-a-rock code.
+ * In Linux, the page cache provides read buffering and the short op cache
+ * provides write buffering.
+ *
+ * There are a limited number (~10) of cache chunks per device so that we don't
+ * need a very intelligent search.
+ */
+
+static int yaffs_obj_cache_dirty(struct yaffs_obj *obj)
+{
+ struct yaffs_dev *dev = obj->my_dev;
+ int i;
+ struct yaffs_cache *cache;
+ int n_caches = obj->my_dev->param.n_caches;
+
+ for (i = 0; i < n_caches; i++) {
+ cache = &dev->cache[i];
+ if (cache->object == obj && cache->dirty)
+ return 1;
+ }
+
+ return 0;
+}
+
+static void yaffs_flush_file_cache(struct yaffs_obj *obj)
+{
+ struct yaffs_dev *dev = obj->my_dev;
+ int lowest = -99; /* Stop compiler whining. */
+ int i;
+ struct yaffs_cache *cache;
+ int chunk_written = 0;
+ int n_caches = obj->my_dev->param.n_caches;
+
+ if (n_caches > 0) {
+ do {
+ cache = NULL;
+
+ /* Find the dirty cache for this object with the lowest chunk id. */
+ for (i = 0; i < n_caches; i++) {
+ if (dev->cache[i].object == obj &&
+ dev->cache[i].dirty) {
+ if (!cache
+ || dev->cache[i].chunk_id <
+ lowest) {
+ cache = &dev->cache[i];
+ lowest = cache->chunk_id;
+ }
+ }
+ }
+
+ if (cache && !cache->locked) {
+ /* Write it out and free it up */
+
+ chunk_written =
+ yaffs_wr_data_obj(cache->object,
+ cache->chunk_id,
+ cache->data,
+ cache->n_bytes, 1);
+ cache->dirty = 0;
+ cache->object = NULL;
+ }
+
+ } while (cache && chunk_written > 0);
+
+ if (cache)
+ /* Hoosterman, disk full while writing cache out. */
+ yaffs_trace(YAFFS_TRACE_ERROR,
+ "yaffs tragedy: no space during cache write");
+
+ }
+
+}
+
+/*yaffs_flush_whole_cache(dev)
+ *
+ *
+ */
+
+void yaffs_flush_whole_cache(struct yaffs_dev *dev)
+{
+ struct yaffs_obj *obj;
+ int n_caches = dev->param.n_caches;
+ int i;
+
+ /* Find a dirty object in the cache and flush it...
+ * until there are no further dirty objects.
+ */
+ do {
+ obj = NULL;
+ for (i = 0; i < n_caches && !obj; i++) {
+ if (dev->cache[i].object && dev->cache[i].dirty)
+ obj = dev->cache[i].object;
+
+ }
+ if (obj)
+ yaffs_flush_file_cache(obj);
+
+ } while (obj);
+
+}
+
+/* Grab us a cache chunk for use.
+ * First look for an empty one.
+ * Then look for the least recently used non-dirty one.
+ * Then look for the least recently used dirty one...., flush and look again.
+ */
+static struct yaffs_cache *yaffs_grab_chunk_worker(struct yaffs_dev *dev)
+{
+ int i;
+
+ if (dev->param.n_caches > 0) {
+ for (i = 0; i < dev->param.n_caches; i++) {
+ if (!dev->cache[i].object)
+ return &dev->cache[i];
+ }
+ }
+
+ return NULL;
+}
+
+static struct yaffs_cache *yaffs_grab_chunk_cache(struct yaffs_dev *dev)
+{
+ struct yaffs_cache *cache;
+ struct yaffs_obj *the_obj;
+ int usage;
+ int i;
+ int pushout;
+
+ if (dev->param.n_caches > 0) {
+ /* Try find a non-dirty one... */
+
+ cache = yaffs_grab_chunk_worker(dev);
+
+ if (!cache) {
+ /* They were all dirty, find the last recently used object and flush
+ * its cache, then find again.
+ * NB what's here is not very accurate, we actually flush the object
+ * the last recently used page.
+ */
+
+ /* With locking we can't assume we can use entry zero */
+
+ the_obj = NULL;
+ usage = -1;
+ cache = NULL;
+ pushout = -1;
+
+ for (i = 0; i < dev->param.n_caches; i++) {
+ if (dev->cache[i].object &&
+ !dev->cache[i].locked &&
+ (dev->cache[i].last_use < usage
+ || !cache)) {
+ usage = dev->cache[i].last_use;
+ the_obj = dev->cache[i].object;
+ cache = &dev->cache[i];
+ pushout = i;
+ }
+ }
+
+ if (!cache || cache->dirty) {
+ /* Flush and try again */
+ yaffs_flush_file_cache(the_obj);
+ cache = yaffs_grab_chunk_worker(dev);
+ }
+
+ }
+ return cache;
+ } else {
+ return NULL;
+ }
+}
+
+/* Find a cached chunk */
+static struct yaffs_cache *yaffs_find_chunk_cache(const struct yaffs_obj *obj,
+ int chunk_id)
+{
+ struct yaffs_dev *dev = obj->my_dev;
+ int i;
+ if (dev->param.n_caches > 0) {
+ for (i = 0; i < dev->param.n_caches; i++) {
+ if (dev->cache[i].object == obj &&
+ dev->cache[i].chunk_id == chunk_id) {
+ dev->cache_hits++;
+
+ return &dev->cache[i];
+ }
+ }
+ }
+ return NULL;
+}
+
+/* Mark the chunk for the least recently used algorithym */
+static void yaffs_use_cache(struct yaffs_dev *dev, struct yaffs_cache *cache,
+ int is_write)
+{
+
+ if (dev->param.n_caches > 0) {
+ if (dev->cache_last_use < 0 || dev->cache_last_use > 100000000) {
+ /* Reset the cache usages */
+ int i;
+ for (i = 1; i < dev->param.n_caches; i++)
+ dev->cache[i].last_use = 0;
+
+ dev->cache_last_use = 0;
+ }
+
+ dev->cache_last_use++;
+
+ cache->last_use = dev->cache_last_use;
+
+ if (is_write)
+ cache->dirty = 1;
+ }
+}
+
+/* Invalidate a single cache page.
+ * Do this when a whole page gets written,
+ * ie the short cache for this page is no longer valid.
+ */
+static void yaffs_invalidate_chunk_cache(struct yaffs_obj *object, int chunk_id)
+{
+ if (object->my_dev->param.n_caches > 0) {
+ struct yaffs_cache *cache =
+ yaffs_find_chunk_cache(object, chunk_id);
+
+ if (cache)
+ cache->object = NULL;
+ }
+}
+
+/* Invalidate all the cache pages associated with this object
+ * Do this whenever ther file is deleted or resized.
+ */
+static void yaffs_invalidate_whole_cache(struct yaffs_obj *in)
+{
+ int i;
+ struct yaffs_dev *dev = in->my_dev;
+
+ if (dev->param.n_caches > 0) {
+ /* Invalidate it. */
+ for (i = 0; i < dev->param.n_caches; i++) {
+ if (dev->cache[i].object == in)
+ dev->cache[i].object = NULL;
+ }
+ }
+}
+
+static void yaffs_unhash_obj(struct yaffs_obj *obj)
+{
+ int bucket;
+ struct yaffs_dev *dev = obj->my_dev;
+
+ /* If it is still linked into the bucket list, free from the list */
+ if (!list_empty(&obj->hash_link)) {
+ list_del_init(&obj->hash_link);
+ bucket = yaffs_hash_fn(obj->obj_id);
+ dev->obj_bucket[bucket].count--;
+ }
+}
+
+/* FreeObject frees up a Object and puts it back on the free list */
+static void yaffs_free_obj(struct yaffs_obj *obj)
+{
+ struct yaffs_dev *dev = obj->my_dev;
+
+ yaffs_trace(YAFFS_TRACE_OS, "FreeObject %p inode %p",
+ obj, obj->my_inode);
+
+ if (!obj)
+ YBUG();
+ if (obj->parent)
+ YBUG();
+ if (!list_empty(&obj->siblings))
+ YBUG();
+
+ if (obj->my_inode) {
+ /* We're still hooked up to a cached inode.
+ * Don't delete now, but mark for later deletion
+ */
+ obj->defered_free = 1;
+ return;
+ }
+
+ yaffs_unhash_obj(obj);
+
+ yaffs_free_raw_obj(dev, obj);
+ dev->n_obj--;
+ dev->checkpoint_blocks_required = 0; /* force recalculation */
+}
+
+void yaffs_handle_defered_free(struct yaffs_obj *obj)
+{
+ if (obj->defered_free)
+ yaffs_free_obj(obj);
+}
+
+static int yaffs_generic_obj_del(struct yaffs_obj *in)
+{
+
+ /* First off, invalidate the file's data in the cache, without flushing. */
+ yaffs_invalidate_whole_cache(in);
+
+ if (in->my_dev->param.is_yaffs2 && (in->parent != in->my_dev->del_dir)) {
+ /* Move to the unlinked directory so we have a record that it was deleted. */
+ yaffs_change_obj_name(in, in->my_dev->del_dir, _Y("deleted"), 0,
+ 0);
+
+ }
+
+ yaffs_remove_obj_from_dir(in);
+ yaffs_chunk_del(in->my_dev, in->hdr_chunk, 1, __LINE__);
+ in->hdr_chunk = 0;
+
+ yaffs_free_obj(in);
+ return YAFFS_OK;
+
+}
+
+static void yaffs_soft_del_file(struct yaffs_obj *obj)
+{
+ if (obj->deleted &&
+ obj->variant_type == YAFFS_OBJECT_TYPE_FILE && !obj->soft_del) {
+ if (obj->n_data_chunks <= 0) {
+ /* Empty file with no duplicate object headers,
+ * just delete it immediately */
+ yaffs_free_tnode(obj->my_dev,
+ obj->variant.file_variant.top);
+ obj->variant.file_variant.top = NULL;
+ yaffs_trace(YAFFS_TRACE_TRACING,
+ "yaffs: Deleting empty file %d",
+ obj->obj_id);
+ yaffs_generic_obj_del(obj);
+ } else {
+ yaffs_soft_del_worker(obj,
+ obj->variant.file_variant.top,
+ obj->variant.
+ file_variant.top_level, 0);
+ obj->soft_del = 1;
+ }
+ }
+}
+
+/* Pruning removes any part of the file structure tree that is beyond the
+ * bounds of the file (ie that does not point to chunks).