| /* |
| * 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 result; |
| 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; |
| |
| result = 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++; |
| |
| result = 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; |
| } |