/* * 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 * * 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; if (!yaffs_rd_chunk_tags_nand(dev, chunk, NULL, &tags)) { yaffs_trace(YAFFS_TRACE_ERROR, "yaffs1_scan: unhandled error from rd_chunk_tags_nand"); } /* 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 < (s32)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++; if (!yaffs_rd_chunk_tags_nand(dev, chunk, chunk_data, NULL)) { yaffs_trace(YAFFS_TRACE_ERROR, "yaffs1_scan: unhandled error from rd_chunk_tags_nand"); } 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; }