--- /dev/null
+/*
+ * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2011 Aleph One Ltd.
+ * for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include "yaffs_yaffs1.h"
+#include "yportenv.h"
+#include "yaffs_trace.h"
+#include "yaffs_bitmap.h"
+#include "yaffs_getblockinfo.h"
+#include "yaffs_nand.h"
+#include "yaffs_attribs.h"
+
+int yaffs1_scan(struct yaffs_dev *dev)
+{
+ struct yaffs_ext_tags tags;
+ int blk;
+ int chunk;
+ int c;
+ int deleted;
+ enum yaffs_block_state state;
+ 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 alloc_failed = 0;
+ struct yaffs_shadow_fixer *shadow_fixers = NULL;
+ u8 *chunk_data;
+
+ yaffs_trace(YAFFS_TRACE_SCAN,
+ "yaffs1_scan starts intstartblk %d intendblk %d...",
+ dev->internal_start_block, dev->internal_end_block);
+
+ chunk_data = yaffs_get_temp_buffer(dev);
+
+ dev->seq_number = YAFFS_LOWEST_SEQUENCE_NUMBER;
+
+ /* Scan all the blocks to determine their state */
+ bi = dev->block_info;
+ for (blk = dev->internal_start_block; blk <= dev->internal_end_block;
+ blk++) {
+ yaffs_clear_chunk_bits(dev, blk);
+ bi->pages_in_use = 0;
+ bi->soft_del_pages = 0;
+
+ yaffs_query_init_block_state(dev, blk, &state, &seq_number);
+
+ bi->block_state = state;
+ bi->seq_number = seq_number;
+
+ if (bi->seq_number == YAFFS_SEQUENCE_BAD_BLOCK)
+ bi->block_state = state = YAFFS_BLOCK_STATE_DEAD;
+
+ yaffs_trace(YAFFS_TRACE_SCAN_DEBUG,
+ "Block scanning block %d state %d seq %d",
+ blk, state, seq_number);
+
+ if (state == YAFFS_BLOCK_STATE_DEAD) {
+ yaffs_trace(YAFFS_TRACE_BAD_BLOCKS,
+ "block %d is bad", blk);
+ } else if (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;
+ }
+ bi++;
+ }
+
+ /* For each block.... */
+ for (blk = dev->internal_start_block;
+ !alloc_failed && blk <= dev->internal_end_block; blk++) {
+
+ cond_resched();
+
+ bi = yaffs_get_block_info(dev, blk);
+ state = bi->block_state;
+
+ deleted = 0;
+
+ /* For each chunk in each block that needs scanning.... */
+ for (c = 0;
+ !alloc_failed && c < dev->param.chunks_per_block &&
+ state == YAFFS_BLOCK_STATE_NEEDS_SCAN; c++) {
+ /* Read the tags and decide what to do */
+ chunk = blk * dev->param.chunks_per_block + c;
+
+ yaffs_rd_chunk_tags_nand(dev, chunk, NULL, &tags);
+
+ /* Let's have a good look at this chunk... */
+
+ if (tags.ecc_result == YAFFS_ECC_RESULT_UNFIXED ||
+ tags.is_deleted) {
+ /* YAFFS1 only...
+ * A deleted chunk
+ */
+ deleted++;
+ dev->n_free_chunks++;
+ } else if (!tags.chunk_used) {
+ /* An unassigned chunk in the block
+ * This means that either the block is empty or
+ * this is the one being allocated from
+ */
+
+ 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 {
+ /* this is the block being allocated */
+ yaffs_trace(YAFFS_TRACE_SCAN,
+ " Allocating from %d %d",
+ blk, c);
+ state = YAFFS_BLOCK_STATE_ALLOCATING;
+ dev->alloc_block = blk;
+ dev->alloc_page = c;
+ dev->alloc_block_finder = blk;
+
+ }
+
+ dev->n_free_chunks +=
+ (dev->param.chunks_per_block - c);
+ } else if (tags.chunk_id > 0) {
+ /* chunk_id > 0 so it is a data chunk... */
+ unsigned int endpos;
+
+ 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);
+ /* PutChunkIntoFile checks for a clash
+ * (two data chunks with the same chunk_id).
+ */
+
+ if (!in)
+ alloc_failed = 1;
+
+ if (in) {
+ if (!yaffs_put_chunk_in_file
+ (in, tags.chunk_id, chunk, 1))
+ alloc_failed = 1;
+ }
+
+ endpos =
+ (tags.chunk_id - 1) *
+ dev->data_bytes_per_chunk +
+ tags.n_bytes;
+ if (in &&
+ in->variant_type ==
+ YAFFS_OBJECT_TYPE_FILE &&
+ in->variant.file_variant.scanned_size <
+ endpos) {
+ in->variant.file_variant.scanned_size =
+ endpos;
+ if (!dev->param.use_header_file_size) {
+ in->variant.
+ file_variant.file_size =
+ in->variant.
+ file_variant.scanned_size;
+ }
+
+ }
+ } else {
+ /* chunk_id == 0, so it is an ObjectHeader.
+ * Make the object
+ */
+ yaffs_set_chunk_bit(dev, blk, c);
+ bi->pages_in_use++;
+
+ yaffs_rd_chunk_tags_nand(dev, chunk,
+ chunk_data, NULL);
+
+ oh = (struct yaffs_obj_hdr *)chunk_data;
+
+ in = yaffs_find_by_number(dev, tags.obj_id);
+ if (in && in->variant_type != oh->type) {
+ /* This should not happen, but somehow
+ * Wev'e ended up with an obj_id that
+ * has been reused but not yet deleted,
+ * and worse still it has changed type.
+ * Delete the old object.
+ */
+
+ yaffs_del_obj(in);
+ in = NULL;
+ }
+
+ in = yaffs_find_or_create_by_number(dev,
+ tags.obj_id,
+ oh->type);
+
+ if (!in)
+ alloc_failed = 1;
+
+ if (in && oh->shadows_obj > 0) {
+
+ struct yaffs_shadow_fixer *fixer;
+ fixer =
+ kmalloc(sizeof
+ (struct yaffs_shadow_fixer),
+ GFP_NOFS);
+ if (fixer) {
+ fixer->next = shadow_fixers;
+ shadow_fixers = fixer;
+ fixer->obj_id = tags.obj_id;
+ fixer->shadowed_id =
+ oh->shadows_obj;
+ yaffs_trace(YAFFS_TRACE_SCAN,
+ " Shadow fixer: %d shadows %d",
+ fixer->obj_id,
+ fixer->shadowed_id);
+
+ }
+
+ }
+
+ if (in && in->valid) {
+ /* We have already filled this one.
+ * We have a duplicate and need to
+ * resolve it. */
+
+ unsigned existing_serial = in->serial;
+ unsigned new_serial =
+ tags.serial_number;
+
+ if (((existing_serial + 1) & 3) ==
+ new_serial) {
+ /* Use new one - destroy the
+ * exisiting one */
+ yaffs_chunk_del(dev,
+ in->hdr_chunk,
+ 1, __LINE__);
+ in->valid = 0;
+ } else {
+ /* Use existing - destroy
+ * this one. */
+ yaffs_chunk_del(dev, chunk, 1,
+ __LINE__);
+ }
+ }
+
+ if (in && !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;
+ in->variant_type = oh->type;
+
+ in->yst_mode = oh->yst_mode;
+ yaffs_load_attribs(in, oh);
+ in->hdr_chunk = chunk;
+ in->serial = tags.serial_number;
+
+ } else if (in && !in->valid) {
+ /* we need to load this info */
+
+ in->valid = 1;
+ in->variant_type = oh->type;
+
+ in->yst_mode = oh->yst_mode;
+ yaffs_load_attribs(in, oh);
+ in->hdr_chunk = chunk;
+ in->serial = tags.serial_number;
+
+ yaffs_set_obj_name_from_oh(in, oh);
+ in->dirty = 0;
+
+ /* directory stuff...
+ * hook up to parent
+ */
+
+ parent =
+ yaffs_find_or_create_by_number
+ (dev, oh->parent_obj_id,
+ YAFFS_OBJECT_TYPE_DIRECTORY);
+ if (!parent)
+ alloc_failed = 1;
+ 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, a problem....
+ * We're 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);
+
+ switch (in->variant_type) {
+ case YAFFS_OBJECT_TYPE_UNKNOWN:
+ /* Todo got a problem */
+ break;
+ case YAFFS_OBJECT_TYPE_FILE:
+ if (dev->param.
+ use_header_file_size)
+ in->variant.
+ file_variant.file_size
+ = yaffs_oh_to_size(oh);
+ break;
+ case YAFFS_OBJECT_TYPE_HARDLINK:
+ in->variant.
+ hardlink_variant.equiv_id =
+ oh->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:
+ in->variant.symlink_variant.
+ alias =
+ yaffs_clone_str(oh->alias);
+ if (!in->variant.
+ symlink_variant.alias)
+ alloc_failed = 1;
+ break;
+ }
+ }
+ }
+ }
+
+ if (state == YAFFS_BLOCK_STATE_NEEDS_SCAN) {
+ /* If we got this far while scanning,
+ * then the block is fully allocated. */
+ state = YAFFS_BLOCK_STATE_FULL;
+ }
+
+ if (state == YAFFS_BLOCK_STATE_ALLOCATING) {
+ /* If the block was partially allocated then
+ * treat it as fully allocated. */
+ state = YAFFS_BLOCK_STATE_FULL;
+ dev->alloc_block = -1;
+ }
+
+ bi->block_state = state;
+
+ /* Now let's see if it was dirty */
+ if (bi->pages_in_use == 0 &&
+ !bi->has_shrink_hdr &&
+ bi->block_state == YAFFS_BLOCK_STATE_FULL)
+ yaffs_block_became_dirty(dev, blk);
+ }
+
+ /* 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 hardlinks.
+ */
+
+ yaffs_link_fixup(dev, &hard_list);
+
+ /*
+ * Fix up any shadowed objects.
+ * There should not be more than one of these.
+ */
+ {
+ struct yaffs_shadow_fixer *fixer;
+ struct yaffs_obj *obj;
+
+ while (shadow_fixers) {
+ fixer = shadow_fixers;
+ shadow_fixers = fixer->next;
+ /* Complete the rename transaction by deleting the
+ * shadowed object then setting the object header
+ to unshadowed.
+ */
+ obj = yaffs_find_by_number(dev, fixer->shadowed_id);
+ if (obj)
+ yaffs_del_obj(obj);
+
+ obj = yaffs_find_by_number(dev, fixer->obj_id);
+
+ if (obj)
+ yaffs_update_oh(obj, NULL, 1, 0, 0, NULL);
+
+ kfree(fixer);
+ }
+ }
+
+ yaffs_release_temp_buffer(dev, chunk_data);
+
+ if (alloc_failed)
+ return YAFFS_FAIL;
+
+ yaffs_trace(YAFFS_TRACE_SCAN, "yaffs1_scan ends");
+
+ return YAFFS_OK;
+}
Code Review / kvmfornfv.git / blobdiff