diff options
Diffstat (limited to 'fs/yaffs2/yaffs_yaffs1.c')
-rw-r--r-- | fs/yaffs2/yaffs_yaffs1.c | 433 |
1 files changed, 433 insertions, 0 deletions
diff --git a/fs/yaffs2/yaffs_yaffs1.c b/fs/yaffs2/yaffs_yaffs1.c new file mode 100644 index 00000000000..9eb60308254 --- /dev/null +++ b/fs/yaffs2/yaffs_yaffs1.c @@ -0,0 +1,433 @@ +/* + * YAFFS: Yet Another Flash File System. A NAND-flash specific file system. + * + * Copyright (C) 2002-2010 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; + struct yaffs_obj *hard_list = NULL; + 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, __LINE__); + + 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_SCANNING; 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++; + /*T((" %d %d deleted\n",blk,c)); */ + } 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 from */ + 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; + /* Set block finder here to encourage the allocator to go forth from here. */ + + } + + 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; + } + + } + /* T((" %d %d data %d %d\n",blk,c,tags.obj_id,tags.chunk_id)); */ + } else { + /* chunk_id == 0, so it is an ObjectHeader. + * Thus, we read in the object header and 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 = 0; + } + + 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, another 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); + + if (0 && (parent == dev->del_dir || + parent == + dev->unlinked_dir)) { + in->deleted = 1; /* If it is unlinked at start up then it wants deleting */ + dev->n_deleted_files++; + } + /* 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 (dev->param. + use_header_file_size) + + in->variant. + file_variant.file_size + = oh->file_size; + + break; + case YAFFS_OBJECT_TYPE_HARDLINK: + in->variant. + hardlink_variant.equiv_id = + oh->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: + 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_SCANNING) { + /* 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 */ + { + 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, __LINE__); + + if (alloc_failed) + return YAFFS_FAIL; + + yaffs_trace(YAFFS_TRACE_SCAN, "yaffs1_scan ends"); + + return YAFFS_OK; +} |