/* * 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_guts.h" #include "yaffs_trace.h" #include "yaffs_yaffs2.h" #include "yaffs_checkptrw.h" #include "yaffs_bitmap.h" #include "yaffs_nand.h" #include "yaffs_getblockinfo.h" #include "yaffs_verify.h" #include "yaffs_attribs.h" /* * Checkpoints are really no benefit on very small partitions. * * To save space on small partitions don't bother with checkpoints unless * the partition is at least this big. */ #define YAFFS_CHECKPOINT_MIN_BLOCKS 60 #define YAFFS_SMALL_HOLE_THRESHOLD 4 /* * Oldest Dirty Sequence Number handling. */ /* yaffs_calc_oldest_dirty_seq() * yaffs2_find_oldest_dirty_seq() * Calculate the oldest dirty sequence number if we don't know it. */ void yaffs_calc_oldest_dirty_seq(struct yaffs_dev *dev) { int i; unsigned seq; unsigned block_no = 0; struct yaffs_block_info *b; if (!dev->param.is_yaffs2) return; /* Find the oldest dirty sequence number. */ seq = dev->seq_number + 1; b = dev->block_info; for (i = dev->internal_start_block; i <= dev->internal_end_block; i++) { if (b->block_state == YAFFS_BLOCK_STATE_FULL && (b->pages_in_use - b->soft_del_pages) < dev->param.chunks_per_block && b->seq_number < seq) { seq = b->seq_number; block_no = i; } b++; } if (block_no) { dev->oldest_dirty_seq = seq; dev->oldest_dirty_block = block_no; } } void yaffs2_find_oldest_dirty_seq(struct yaffs_dev *dev) { if (!dev->param.is_yaffs2) return; if (!dev->oldest_dirty_seq) yaffs_calc_oldest_dirty_seq(dev); } /* * yaffs_clear_oldest_dirty_seq() * Called when a block is erased or marked bad. (ie. when its seq_number * becomes invalid). If the value matches the oldest then we clear * dev->oldest_dirty_seq to force its recomputation. */ void yaffs2_clear_oldest_dirty_seq(struct yaffs_dev *dev, struct yaffs_block_info *bi) { if (!dev->param.is_yaffs2) return; if (!bi || bi->seq_number == dev->oldest_dirty_seq) { dev->oldest_dirty_seq = 0; dev->oldest_dirty_block = 0; } } /* * yaffs2_update_oldest_dirty_seq() * Update the oldest dirty sequence number whenever we dirty a block. * Only do this if the oldest_dirty_seq is actually being tracked. */ void yaffs2_update_oldest_dirty_seq(struct yaffs_dev *dev, unsigned block_no, struct yaffs_block_info *bi) { if (!dev->param.is_yaffs2) return; if (dev->oldest_dirty_seq) { if (dev->oldest_dirty_seq > bi->seq_number) { dev->oldest_dirty_seq = bi->seq_number; dev->oldest_dirty_block = block_no; } } } int yaffs_block_ok_for_gc(struct yaffs_dev *dev, struct yaffs_block_info *bi) { if (!dev->param.is_yaffs2) return 1; /* disqualification only applies to yaffs2. */ if (!bi->has_shrink_hdr) return 1; /* can gc */ yaffs2_find_oldest_dirty_seq(dev); /* Can't do gc of this block if there are any blocks older than this one that have * discarded pages. */ return (bi->seq_number <= dev->oldest_dirty_seq); } /* * yaffs2_find_refresh_block() * periodically finds the oldest full block by sequence number for refreshing. * Only for yaffs2. */ u32 yaffs2_find_refresh_block(struct yaffs_dev * dev) { u32 b; u32 oldest = 0; u32 oldest_seq = 0; struct yaffs_block_info *bi; if (!dev->param.is_yaffs2) return oldest; /* * If refresh period < 10 then refreshing is disabled. */ if (dev->param.refresh_period < 10) return oldest; /* * Fix broken values. */ if (dev->refresh_skip > dev->param.refresh_period) dev->refresh_skip = dev->param.refresh_period; if (dev->refresh_skip > 0) return oldest; /* * Refresh skip is now zero. * We'll do a refresh this time around.... * Update the refresh skip and find the oldest block. */ dev->refresh_skip = dev->param.refresh_period; dev->refresh_count++; bi = dev->block_info; for (b = dev->internal_start_block; b <= dev->internal_end_block; b++) { if (bi->block_state == YAFFS_BLOCK_STATE_FULL) { if (oldest < 1 || bi->seq_number < oldest_seq) { oldest = b; oldest_seq = bi->seq_number; } } bi++; } if (oldest > 0) { yaffs_trace(YAFFS_TRACE_GC, "GC refresh count %d selected block %d with seq_number %d", dev->refresh_count, oldest, oldest_seq); } return oldest; } int yaffs2_checkpt_required(struct yaffs_dev *dev) { int nblocks; if (!dev->param.is_yaffs2) return 0; nblocks = dev->internal_end_block - dev->internal_start_block + 1; return !dev->param.skip_checkpt_wr && !dev->read_only && (nblocks >= YAFFS_CHECKPOINT_MIN_BLOCKS); } int yaffs_calc_checkpt_blocks_required(struct yaffs_dev *dev) { int retval; if (!dev->param.is_yaffs2) return 0; if (!dev->checkpoint_blocks_required && yaffs2_checkpt_required(dev)) { /* Not a valid value so recalculate */ int n_bytes = 0; int n_blocks; int dev_blocks = (dev->param.end_block - dev->param.start_block + 1); n_bytes += sizeof(struct yaffs_checkpt_validity); n_bytes += sizeof(struct yaffs_checkpt_dev); n_bytes += dev_blocks * sizeof(struct yaffs_block_info); n_bytes += dev_blocks * dev->chunk_bit_stride; n_bytes += (sizeof(struct yaffs_checkpt_obj) + sizeof(u32)) * (dev->n_obj); n_bytes += (dev->tnode_size + sizeof(u32)) * (dev->n_tnodes); n_bytes += sizeof(struct yaffs_checkpt_validity); n_bytes += sizeof(u32); /* checksum */ /* Round up and add 2 blocks to allow for some bad blocks, so add 3 */ n_blocks = (n_bytes / (dev->data_bytes_per_chunk * dev->param.chunks_per_block)) + 3; dev->checkpoint_blocks_required = n_blocks; } retval = dev->checkpoint_blocks_required - dev->blocks_in_checkpt; if (retval < 0) retval = 0; return retval; } /*--------------------- Checkpointing --------------------*/ static int yaffs2_wr_checkpt_validity_marker(struct yaffs_dev *dev, int head) { struct yaffs_checkpt_validity cp; memset(&cp, 0, sizeof(cp)); cp.struct_type = sizeof(cp); cp.magic = YAFFS_MAGIC; cp.version = YAFFS_CHECKPOINT_VERSION; cp.head = (head) ? 1 : 0; return (yaffs2_checkpt_wr(dev, &cp, sizeof(cp)) == sizeof(cp)) ? 1 : 0; } static int yaffs2_rd_checkpt_validity_marker(struct yaffs_dev *dev, int head) { struct yaffs_checkpt_validity cp; int ok; ok = (yaffs2_checkpt_rd(dev, &cp, sizeof(cp)) == sizeof(cp)); if (ok) ok = (cp.struct_type == sizeof(cp)) && (cp.magic == YAFFS_MAGIC) && (cp.version == YAFFS_CHECKPOINT_VERSION) && (cp.head == ((head) ? 1 : 0)); return ok ? 1 : 0; } static void yaffs2_dev_to_checkpt_dev(struct yaffs_checkpt_dev *cp, struct yaffs_dev *dev) { cp->n_erased_blocks = dev->n_erased_blocks; cp->alloc_block = dev->alloc_block; cp->alloc_page = dev->alloc_page; cp->n_free_chunks = dev->n_free_chunks; cp->n_deleted_files = dev->n_deleted_files; cp->n_unlinked_files = dev->n_unlinked_files; cp->n_bg_deletions = dev->n_bg_deletions; cp->seq_number = dev->seq_number; } static void yaffs_checkpt_dev_to_dev(struct yaffs_dev *dev, struct yaffs_checkpt_dev *cp) { dev->n_erased_blocks = cp->n_erased_blocks; dev->alloc_block = cp->alloc_block; dev->alloc_page = cp->alloc_page; dev->n_free_chunks = cp->n_free_chunks; dev->n_deleted_files = cp->n_deleted_files; dev->n_unlinked_files = cp->n_unlinked_files; dev->n_bg_deletions = cp->n_bg_deletions; dev->seq_number = cp->seq_number; } static int yaffs2_wr_checkpt_dev(struct yaffs_dev *dev) { struct yaffs_checkpt_dev cp; u32 n_bytes; u32 n_blocks = (dev->internal_end_block - dev->internal_start_block + 1); int ok; /* Write device runtime values */ yaffs2_dev_to_checkpt_dev(&cp, dev); cp.struct_type = sizeof(cp); ok = (yaffs2_checkpt_wr(dev, &cp, sizeof(cp)) == sizeof(cp)); /* Write block info */ if (ok) { n_bytes = n_blocks * sizeof(struct yaffs_block_info); ok = (yaffs2_checkpt_wr(dev, dev->block_info, n_bytes) == n_bytes); } /* Write chunk bits */ if (ok) { n_bytes = n_blocks * dev->chunk_bit_stride; ok = (yaffs2_checkpt_wr(dev, dev->chunk_bits, n_bytes) == n_bytes); } return ok ? 1 : 0; } static int yaffs2_rd_checkpt_dev(struct yaffs_dev *dev) { struct yaffs_checkpt_dev cp; u32 n_bytes; u32 n_blocks = (dev->internal_end_block - dev->internal_start_block + 1); int ok; ok = (yaffs2_checkpt_rd(dev, &cp, sizeof(cp)) == sizeof(cp)); if (!ok) return 0; if (cp.struct_type != sizeof(cp)) return 0; yaffs_checkpt_dev_to_dev(dev, &cp); n_bytes = n_blocks * sizeof(struct yaffs_block_info); ok = (yaffs2_checkpt_rd(dev, dev->block_info, n_bytes) == n_bytes); if (!ok) return 0; n_bytes = n_blocks * dev->chunk_bit_stride; ok = (yaffs2_checkpt_rd(dev, dev->chunk_bits, n_bytes) == n_bytes); return ok ? 1 : 0; } static void yaffs2_obj_checkpt_obj(struct yaffs_checkpt_obj *cp, struct yaffs_obj *obj) { cp->obj_id = obj->obj_id; cp->parent_id = (obj->parent) ? obj->parent->obj_id : 0; cp->hdr_chunk = obj->hdr_chunk; cp->variant_type = obj->variant_type; cp->deleted = obj->deleted; cp->soft_del = obj->soft_del; cp->unlinked = obj->unlinked; cp->fake = obj->fake; cp->rename_allowed = obj->rename_allowed; cp->unlink_allowed = obj->unlink_allowed; cp->serial = obj->serial; cp->n_data_chunks = obj->n_data_chunks; if (obj->variant_type == YAFFS_OBJECT_TYPE_FILE) cp->size_or_equiv_obj = obj->variant.file_variant.file_size; else if (obj->variant_type == YAFFS_OBJECT_TYPE_HARDLINK) cp->size_or_equiv_obj = obj->variant.hardlink_variant.equiv_id; } static int taffs2_checkpt_obj_to_obj(struct yaffs_obj *obj, struct yaffs_checkpt_obj *cp) { struct yaffs_obj *parent; if (obj->variant_type != cp->variant_type) { yaffs_trace(YAFFS_TRACE_ERROR, "Checkpoint read object %d type %d chunk %d does not match existing object type %d", cp->obj_id, cp->variant_type, cp->hdr_chunk, obj->variant_type); return 0; } obj->obj_id = cp->obj_id; if (cp->parent_id) parent = yaffs_find_or_create_by_number(obj->my_dev, cp->parent_id, YAFFS_OBJECT_TYPE_DIRECTORY); else parent = NULL; if (parent) { if (parent->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY) { yaffs_trace(YAFFS_TRACE_ALWAYS, "Checkpoint read object %d parent %d type %d chunk %d Parent type, %d, not directory", cp->obj_id, cp->parent_id, cp->variant_type, cp->hdr_chunk, parent->variant_type); return 0; } yaffs_add_obj_to_dir(parent, obj); } obj->hdr_chunk = cp->hdr_chunk; obj->variant_type = cp->variant_type; obj->deleted = cp->deleted; obj->soft_del = cp->soft_del; obj->unlinked = cp->unlinked; obj->fake = cp->fake; obj->rename_allowed = cp->rename_allowed; obj->unlink_allowed = cp->unlink_allowed; obj->serial = cp->serial; obj->n_data_chunks = cp->n_data_chunks; if (obj->variant_type == YAFFS_OBJECT_TYPE_FILE) obj->variant.file_variant.file_size = cp->size_or_equiv_obj; else if (obj->variant_type == YAFFS_OBJECT_TYPE_HARDLINK) obj->variant.hardlink_variant.equiv_id = cp->size_or_equiv_obj; if (obj->hdr_chunk > 0) obj->lazy_loaded = 1; return 1; } static int yaffs2_checkpt_tnode_worker(struct yaffs_obj *in, struct yaffs_tnode *tn, u32 level, int chunk_offset) { int i; struct yaffs_dev *dev = in->my_dev; int ok = 1; if (tn) { if (level > 0) { for (i = 0; i < YAFFS_NTNODES_INTERNAL && ok; i++) { if (tn->internal[i]) { ok = yaffs2_checkpt_tnode_worker(in, tn-> internal [i], level - 1, (chunk_offset << YAFFS_TNODES_INTERNAL_BITS) + i); } } } else if (level == 0) { u32 base_offset = chunk_offset << YAFFS_TNODES_LEVEL0_BITS; ok = (yaffs2_checkpt_wr (dev, &base_offset, sizeof(base_offset)) == sizeof(base_offset)); if (ok) ok = (yaffs2_checkpt_wr (dev, tn, dev->tnode_size) == dev->tnode_size); } } return ok; } static int yaffs2_wr_checkpt_tnodes(struct yaffs_obj *obj) { u32 end_marker = ~0; int ok = 1; if (obj->variant_type == YAFFS_OBJECT_TYPE_FILE) { ok = yaffs2_checkpt_tnode_worker(obj, obj->variant.file_variant.top, obj->variant.file_variant. top_level, 0); if (ok) ok = (yaffs2_checkpt_wr (obj->my_dev, &end_marker, sizeof(end_marker)) == sizeof(end_marker)); } return ok ? 1 : 0; } static int yaffs2_rd_checkpt_tnodes(struct yaffs_obj *obj) { u32 base_chunk; int ok = 1; struct yaffs_dev *dev = obj->my_dev; struct yaffs_file_var *file_stuct_ptr = &obj->variant.file_variant; struct yaffs_tnode *tn; int nread = 0; ok = (yaffs2_checkpt_rd(dev, &base_chunk, sizeof(base_chunk)) == sizeof(base_chunk)); while (ok && (~base_chunk)) { nread++; /* Read level 0 tnode */ tn = yaffs_get_tnode(dev); if (tn) { ok = (yaffs2_checkpt_rd(dev, tn, dev->tnode_size) == dev->tnode_size); } else { ok = 0; } if (tn && ok) ok = yaffs_add_find_tnode_0(dev, file_stuct_ptr, base_chunk, tn) ? 1 : 0; if (ok) ok = (yaffs2_checkpt_rd (dev, &base_chunk, sizeof(base_chunk)) == sizeof(base_chunk)); } yaffs_trace(YAFFS_TRACE_CHECKPOINT, "Checkpoint read tnodes %d records, last %d. ok %d", nread, base_chunk, ok); return ok ? 1 : 0; } static int yaffs2_wr_checkpt_objs(struct yaffs_dev *dev) { struct yaffs_obj *obj; struct yaffs_checkpt_obj cp; int i; int ok = 1; struct list_head *lh; /* Iterate through the objects in each hash entry, * dumping them to the checkpointing stream. */ for (i = 0; ok && i < YAFFS_NOBJECT_BUCKETS; i++) { list_for_each(lh, &dev->obj_bucket[i].list) { if (lh) { obj = list_entry(lh, struct yaffs_obj, hash_link); if (!obj->defered_free) { yaffs2_obj_checkpt_obj(&cp, obj); cp.struct_type = sizeof(cp); yaffs_trace(YAFFS_TRACE_CHECKPOINT, "Checkpoint write object %d parent %d type %d chunk %d obj addr %p", cp.obj_id, cp.parent_id, cp.variant_type, cp.hdr_chunk, obj); ok = (yaffs2_checkpt_wr (dev, &cp, sizeof(cp)) == sizeof(cp)); if (ok && obj->variant_type == YAFFS_OBJECT_TYPE_FILE) ok = yaffs2_wr_checkpt_tnodes (obj); } } } } /* Dump end of list */ memset(&cp, 0xFF, sizeof(struct yaffs_checkpt_obj)); cp.struct_type = sizeof(cp); if (ok) ok = (yaffs2_checkpt_wr(dev, &cp, sizeof(cp)) == sizeof(cp)); return ok ? 1 : 0; } static int yaffs2_rd_checkpt_objs(struct yaffs_dev *dev) { struct yaffs_obj *obj; struct yaffs_checkpt_obj cp; int ok = 1; int done = 0; struct yaffs_obj *hard_list = NULL; while (ok && !done) { ok = (yaffs2_checkpt_rd(dev, &cp, sizeof(cp)) == sizeof(cp)); if (cp.struct_type != sizeof(cp)) { yaffs_trace(YAFFS_TRACE_CHECKPOINT, "struct size %d instead of %d ok %d", cp.struct_type, (int)sizeof(cp), ok); ok = 0; } yaffs_trace(YAFFS_TRACE_CHECKPOINT, "Checkpoint read object %d parent %d type %d chunk %d ", cp.obj_id, cp.parent_id, cp.variant_type, cp.hdr_chunk); if (ok && cp.obj_id == ~0) { done = 1; } else if (ok) { obj = yaffs_find_or_create_by_number(dev, cp.obj_id, cp.variant_type); if (obj) { ok = taffs2_checkpt_obj_to_obj(obj, &cp); if (!ok) break; if (obj->variant_type == YAFFS_OBJECT_TYPE_FILE) { ok = yaffs2_rd_checkpt_tnodes(obj); } else if (obj->variant_type == YAFFS_OBJECT_TYPE_HARDLINK) { obj->hard_links.next = (struct list_head *)hard_list; hard_list = obj; } } else { ok = 0; } } } if (ok) yaffs_link_fixup(dev, hard_list); return ok ? 1 : 0; } static int yaffs2_wr_checkpt_sum(struct yaffs_dev *dev) { u32 checkpt_sum; int ok; yaffs2_get_checkpt_sum(dev, &checkpt_sum); ok = (yaffs2_checkpt_wr(dev, &checkpt_sum, sizeof(checkpt_sum)) == sizeof(checkpt_sum)); if (!ok) return 0; return 1; } static int yaffs2_rd_checkpt_sum(struct yaffs_dev *dev) { u32 checkpt_sum0; u32 checkpt_sum1; int ok; yaffs2_get_checkpt_sum(dev, &checkpt_sum0); ok = (yaffs2_checkpt_rd(dev, &checkpt_sum1, sizeof(checkpt_sum1)) == sizeof(checkpt_sum1)); if (!ok) return 0; if (checkpt_sum0 != checkpt_sum1) return 0; return 1; } static int yaffs2_wr_checkpt_data(struct yaffs_dev *dev) { int ok = 1; if (!yaffs2_checkpt_required(dev)) { yaffs_trace(YAFFS_TRACE_CHECKPOINT, "skipping checkpoint write"); ok = 0; } if (ok) ok = yaffs2_checkpt_open(dev, 1); if (ok) { yaffs_trace(YAFFS_TRACE_CHECKPOINT, "write checkpoint validity"); ok = yaffs2_wr_checkpt_validity_marker(dev, 1); } if (ok) { yaffs_trace(YAFFS_TRACE_CHECKPOINT, "write checkpoint device"); ok = yaffs2_wr_checkpt_dev(dev); } if (ok) { yaffs_trace(YAFFS_TRACE_CHECKPOINT, "write checkpoint objects"); ok = yaffs2_wr_checkpt_objs(dev); } if (ok) { yaffs_trace(YAFFS_TRACE_CHECKPOINT, "write checkpoint validity"); ok = yaffs2_wr_checkpt_validity_marker(dev, 0); } if (ok) ok = yaffs2_wr_checkpt_sum(dev); if (!yaffs_checkpt_close(dev)) ok = 0; if (ok) dev->is_checkpointed = 1; else dev->is_checkpointed = 0; return dev->is_checkpointed; } static int yaffs2_rd_checkpt_data(struct yaffs_dev *dev) { int ok = 1; if (!dev->param.is_yaffs2) ok = 0; if (ok && dev->param.skip_checkpt_rd) { yaffs_trace(YAFFS_TRACE_CHECKPOINT, "skipping checkpoint read"); ok = 0; } if (ok) ok = yaffs2_checkpt_open(dev, 0); /* open for read */ if (ok) { yaffs_trace(YAFFS_TRACE_CHECKPOINT, "read checkpoint validity"); ok = yaffs2_rd_checkpt_validity_marker(dev, 1); } if (ok) { yaffs_trace(YAFFS_TRACE_CHECKPOINT, "read checkpoint device"); ok = yaffs2_rd_checkpt_dev(dev); } if (ok) { yaffs_trace(YAFFS_TRACE_CHECKPOINT, "read checkpoint objects"); ok = yaffs2_rd_checkpt_objs(dev); } if (ok) { yaffs_trace(YAFFS_TRACE_CHECKPOINT, "read checkpoint validity"); ok = yaffs2_rd_checkpt_validity_marker(dev, 0); } if (ok) { ok = yaffs2_rd_checkpt_sum(dev); yaffs_trace(YAFFS_TRACE_CHECKPOINT, "read checkpoint checksum %d", ok); } if (!yaffs_checkpt_close(dev)) ok = 0; if (ok) dev->is_checkpointed = 1; else dev->is_checkpointed = 0; return ok ? 1 : 0; } void yaffs2_checkpt_invalidate(struct yaffs_dev *dev) { if (dev->is_checkpointed || dev->blocks_in_checkpt > 0) { dev->is_checkpointed = 0; yaffs2_checkpt_invalidate_stream(dev); } if (dev->param.sb_dirty_fn) dev->param.sb_dirty_fn(dev); } int yaffs_checkpoint_save(struct yaffs_dev *dev) { yaffs_trace(YAFFS_TRACE_CHECKPOINT, "save entry: is_checkpointed %d", dev->is_checkpointed); yaffs_verify_objects(dev); yaffs_verify_blocks(dev); yaffs_verify_free_chunks(dev); if (!dev->is_checkpointed) { yaffs2_checkpt_invalidate(dev); yaffs2_wr_checkpt_data(dev); } yaffs_trace(YAFFS_TRACE_CHECKPOINT | YAFFS_TRACE_MOUNT, "save exit: is_checkpointed %d", dev->is_checkpointed); return dev->is_checkpointed; } int yaffs2_checkpt_restore(struct yaffs_dev *dev) { int retval; yaffs_trace(YAFFS_TRACE_CHECKPOINT, "restore entry: is_checkpointed %d", dev->is_checkpointed); retval = yaffs2_rd_checkpt_data(dev); if (dev->is_checkpointed) { yaffs_verify_objects(dev); yaffs_verify_blocks(dev); yaffs_verify_free_chunks(dev); } yaffs_trace(YAFFS_TRACE_CHECKPOINT, "restore exit: is_checkpointed %d", dev->is_checkpointed); return retval; } int yaffs2_handle_hole(struct yaffs_obj *obj, loff_t new_size) { /* if new_size > old_file_size. * We're going to be writing a hole. * If the hole is small then write zeros otherwise write a start of hole marker. */ loff_t old_file_size; int increase; int small_hole; int result = YAFFS_OK; struct yaffs_dev *dev = NULL; u8 *local_buffer = NULL; int small_increase_ok = 0; if (!obj) return YAFFS_FAIL; if (obj->variant_type != YAFFS_OBJECT_TYPE_FILE) return YAFFS_FAIL; dev = obj->my_dev; /* Bail out if not yaffs2 mode */ if (!dev->param.is_yaffs2) return YAFFS_OK; old_file_size = obj->variant.file_variant.file_size; if (new_size <= old_file_size) return YAFFS_OK; increase = new_size - old_file_size; if (increase < YAFFS_SMALL_HOLE_THRESHOLD * dev->data_bytes_per_chunk && yaffs_check_alloc_available(dev, YAFFS_SMALL_HOLE_THRESHOLD + 1)) small_hole = 1; else small_hole = 0; if (small_hole) local_buffer = yaffs_get_temp_buffer(dev, __LINE__); if (local_buffer) { /* fill hole with zero bytes */ int pos = old_file_size; int this_write; int written; memset(local_buffer, 0, dev->data_bytes_per_chunk); small_increase_ok = 1; while (increase > 0 && small_increase_ok) { this_write = increase; if (this_write > dev->data_bytes_per_chunk) this_write = dev->data_bytes_per_chunk; written = yaffs_do_file_wr(obj, local_buffer, pos, this_write, 0); if (written == this_write) { pos += this_write; increase -= this_write; } else { small_increase_ok = 0; } } yaffs_release_temp_buffer(dev, local_buffer, __LINE__); /* If we were out of space then reverse any chunks we've added */ if (!small_increase_ok) yaffs_resize_file_down(obj, old_file_size); } if (!small_increase_ok && obj->parent && obj->parent->obj_id != YAFFS_OBJECTID_UNLINKED && obj->parent->obj_id != YAFFS_OBJECTID_DELETED) { /* Write a hole start header with the old file size */ yaffs_update_oh(obj, NULL, 0, 1, 0, NULL); } return result; } struct yaffs_block_index { int seq; int block; }; static int yaffs2_ybicmp(const void *a, const void *b) { int aseq = ((struct yaffs_block_index *)a)->seq; int bseq = ((struct yaffs_block_index *)b)->seq; int ablock = ((struct yaffs_block_index *)a)->block; int bblock = ((struct yaffs_block_index *)b)->block; if (aseq == bseq) return ablock - bblock; else return aseq - bseq; } int yaffs2_scan_backwards(struct yaffs_dev *dev) { struct yaffs_ext_tags tags; int blk; int block_iter; int start_iter; int end_iter; int n_to_scan = 0; int chunk; int result; 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 n_blocks = dev->internal_end_block - dev->internal_start_block + 1; int is_unlinked; u8 *chunk_data; int file_size; int is_shrink; int found_chunks; int equiv_id; int alloc_failed = 0; struct yaffs_block_index *block_index = NULL; int alt_block_index = 0; yaffs_trace(YAFFS_TRACE_SCAN, "yaffs2_scan_backwards starts intstartblk %d intendblk %d...", dev->internal_start_block, dev->internal_end_block); dev->seq_number = YAFFS_LOWEST_SEQUENCE_NUMBER; block_index = kmalloc(n_blocks * sizeof(struct yaffs_block_index), GFP_NOFS); if (!block_index) { block_index = vmalloc(n_blocks * sizeof(struct yaffs_block_index)); alt_block_index = 1; } if (!block_index) { yaffs_trace(YAFFS_TRACE_SCAN, "yaffs2_scan_backwards() could not allocate block index!" ); return YAFFS_FAIL; } dev->blocks_in_checkpt = 0; chunk_data = yaffs_get_temp_buffer(dev, __LINE__); /* 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_CHECKPOINT_DATA) bi->block_state = state = YAFFS_BLOCK_STATE_CHECKPOINT; 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_CHECKPOINT) { dev->blocks_in_checkpt++; } else 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; } else if (state == YAFFS_BLOCK_STATE_NEEDS_SCANNING) { /* Determine the highest sequence number */ if (seq_number >= YAFFS_LOWEST_SEQUENCE_NUMBER && seq_number < YAFFS_HIGHEST_SEQUENCE_NUMBER) { block_index[n_to_scan].seq = seq_number; block_index[n_to_scan].block = blk; n_to_scan++; if (seq_number >= dev->seq_number) dev->seq_number = seq_number; } else { /* TODO: Nasty sequence number! */ yaffs_trace(YAFFS_TRACE_SCAN, "Block scanning block %d has bad sequence number %d", blk, seq_number); } } bi++; } yaffs_trace(YAFFS_TRACE_SCAN, "%d blocks to be sorted...", n_to_scan); cond_resched(); /* Sort the blocks by sequence number */ sort(block_index, n_to_scan, sizeof(struct yaffs_block_index), yaffs2_ybicmp, NULL); cond_resched(); yaffs_trace(YAFFS_TRACE_SCAN, "...done"); /* Now scan the blocks looking at the data. */ start_iter = 0; end_iter = n_to_scan - 1; yaffs_trace(YAFFS_TRACE_SCAN_DEBUG, "%d blocks to scan", n_to_scan); /* For each block.... backwards */ for (block_iter = end_iter; !alloc_failed && block_iter >= start_iter; block_iter--) { /* Cooperative multitasking! This loop can run for so long that watchdog timers expire. */ cond_resched(); /* get the block to scan in the correct order */ blk = block_index[block_iter].block; bi = yaffs_get_block_info(dev, blk); state = bi->block_state; deleted = 0; /* For each chunk in each block that needs scanning.... */ found_chunks = 0; for (c = dev->param.chunks_per_block - 1; !alloc_failed && c >= 0 && (state == YAFFS_BLOCK_STATE_NEEDS_SCANNING || state == YAFFS_BLOCK_STATE_ALLOCATING); c--) { /* Scan backwards... * 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.chunk_used) { /* An unassigned chunk in the block. * If there are used chunks after this one, then * it is a chunk that was skipped due to failing the erased * check. Just skip it so that it can be deleted. * But, more typically, We get here when this is an unallocated * chunk and his means that either the block is empty or * this is the one being allocated from */ if (found_chunks) { /* This is a chunk that was skipped due to failing the erased check */ } else 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 { if (state == YAFFS_BLOCK_STATE_NEEDS_SCANNING || state == YAFFS_BLOCK_STATE_ALLOCATING) { if (dev->seq_number == bi->seq_number) { /* 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; } else { /* This is a partially written block that is not * the current allocation block. */ yaffs_trace(YAFFS_TRACE_SCAN, "Partially written block %d detected", blk); } } } dev->n_free_chunks++; } else if (tags.ecc_result == YAFFS_ECC_RESULT_UNFIXED) { yaffs_trace(YAFFS_TRACE_SCAN, " Unfixed ECC in chunk(%d:%d), chunk ignored", blk, c); dev->n_free_chunks++; } else if (tags.obj_id > YAFFS_MAX_OBJECT_ID || tags.chunk_id > YAFFS_MAX_CHUNK_ID || (tags.chunk_id > 0 && tags.n_bytes > dev->data_bytes_per_chunk) || tags.seq_number != bi->seq_number) { yaffs_trace(YAFFS_TRACE_SCAN, "Chunk (%d:%d) with bad tags:obj = %d, chunk_id = %d, n_bytes = %d, ignored", blk, c, tags.obj_id, tags.chunk_id, tags.n_bytes); dev->n_free_chunks++; } else if (tags.chunk_id > 0) { /* chunk_id > 0 so it is a data chunk... */ unsigned int endpos; u32 chunk_base = (tags.chunk_id - 1) * dev->data_bytes_per_chunk; found_chunks = 1; 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); if (!in) { /* Out of memory */ alloc_failed = 1; } if (in && in->variant_type == YAFFS_OBJECT_TYPE_FILE && chunk_base < in->variant.file_variant.shrink_size) { /* This has not been invalidated by a resize */ if (!yaffs_put_chunk_in_file (in, tags.chunk_id, chunk, -1)) { alloc_failed = 1; } /* File size is calculated by looking at the data chunks if we have not * seen an object header yet. Stop this practice once we find an object header. */ endpos = chunk_base + tags.n_bytes; if (!in->valid && /* have not got an object header yet */ in->variant.file_variant. scanned_size < endpos) { in->variant.file_variant. scanned_size = endpos; in->variant.file_variant. file_size = endpos; } } else if (in) { /* This chunk has been invalidated by a resize, or a past file deletion * so delete the chunk*/ yaffs_chunk_del(dev, chunk, 1, __LINE__); } } else { /* chunk_id == 0, so it is an ObjectHeader. * Thus, we read in the object header and make the object */ found_chunks = 1; yaffs_set_chunk_bit(dev, blk, c); bi->pages_in_use++; oh = NULL; in = NULL; if (tags.extra_available) { in = yaffs_find_or_create_by_number(dev, tags. obj_id, tags. extra_obj_type); if (!in) alloc_failed = 1; } if (!in || (!in->valid && dev->param.disable_lazy_load) || tags.extra_shadows || (!in->valid && (tags.obj_id == YAFFS_OBJECTID_ROOT || tags. obj_id == YAFFS_OBJECTID_LOSTNFOUND))) { /* If we don't have valid info then we need to read the chunk * TODO In future we can probably defer reading the chunk and * living with invalid data until needed. */ result = yaffs_rd_chunk_tags_nand(dev, chunk, chunk_data, NULL); oh = (struct yaffs_obj_hdr *)chunk_data; if (dev->param.inband_tags) { /* Fix up the header if they got corrupted by inband tags */ oh->shadows_obj = oh->inband_shadowed_obj_id; oh->is_shrink = oh->inband_is_shrink; } if (!in) { in = yaffs_find_or_create_by_number(dev, tags.obj_id, oh->type); if (!in) alloc_failed = 1; } } if (!in) { /* TODO Hoosterman we have a problem! */ yaffs_trace(YAFFS_TRACE_ERROR, "yaffs tragedy: Could not make object for object %d at chunk %d during scan", tags.obj_id, chunk); continue; } if (in->valid) { /* We have already filled this one. * We have a duplicate that will be discarded, but * we first have to suck out resize info if it is a file. */ if ((in->variant_type == YAFFS_OBJECT_TYPE_FILE) && ((oh && oh-> type == YAFFS_OBJECT_TYPE_FILE) || (tags. extra_available && tags. extra_obj_type == YAFFS_OBJECT_TYPE_FILE))) { u32 this_size = (oh) ? oh-> file_size : tags.extra_length; u32 parent_obj_id = (oh) ? oh->parent_obj_id : tags.extra_parent_id; is_shrink = (oh) ? oh-> is_shrink : tags.extra_is_shrink; /* If it is deleted (unlinked at start also means deleted) * we treat the file size as being zeroed at this point. */ if (parent_obj_id == YAFFS_OBJECTID_DELETED || parent_obj_id == YAFFS_OBJECTID_UNLINKED) { this_size = 0; is_shrink = 1; } if (is_shrink && in->variant.file_variant. shrink_size > this_size) in->variant. file_variant. shrink_size = this_size; if (is_shrink) bi->has_shrink_hdr = 1; } /* Use existing - destroy this one. */ yaffs_chunk_del(dev, chunk, 1, __LINE__); } if (!in->valid && in->variant_type != (oh ? oh->type : tags.extra_obj_type)) yaffs_trace(YAFFS_TRACE_ERROR, "yaffs tragedy: Bad object type, %d != %d, for object %d at chunk %d during scan", oh ? oh->type : tags.extra_obj_type, in->variant_type, tags.obj_id, chunk); if (!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; if (oh) { in->yst_mode = oh->yst_mode; yaffs_load_attribs(in, oh); in->lazy_loaded = 0; } else { in->lazy_loaded = 1; } in->hdr_chunk = chunk; } else if (!in->valid) { /* we need to load this info */ in->valid = 1; in->hdr_chunk = chunk; if (oh) { in->variant_type = oh->type; in->yst_mode = oh->yst_mode; yaffs_load_attribs(in, oh); if (oh->shadows_obj > 0) yaffs_handle_shadowed_obj (dev, oh->shadows_obj, 1); yaffs_set_obj_name_from_oh(in, oh); parent = yaffs_find_or_create_by_number (dev, oh->parent_obj_id, YAFFS_OBJECT_TYPE_DIRECTORY); file_size = oh->file_size; is_shrink = oh->is_shrink; equiv_id = oh->equiv_id; } else { in->variant_type = tags.extra_obj_type; parent = yaffs_find_or_create_by_number (dev, tags.extra_parent_id, YAFFS_OBJECT_TYPE_DIRECTORY); file_size = tags.extra_length; is_shrink = tags.extra_is_shrink; equiv_id = tags.extra_equiv_id; in->lazy_loaded = 1; } in->dirty = 0; if (!parent) alloc_failed = 1; /* directory stuff... * hook up to parent */ 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); is_unlinked = (parent == dev->del_dir) || (parent == dev->unlinked_dir); if (is_shrink) { /* Mark the block as having a shrink header */ bi->has_shrink_hdr = 1; } /* 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 (in->variant. file_variant.scanned_size < file_size) { /* This covers the case where the file size is greater * than where the data is * This will happen if the file is resized to be larger * than its current data extents. */ in->variant. file_variant. file_size = file_size; in->variant. file_variant. scanned_size = file_size; } if (in->variant.file_variant. shrink_size > file_size) in->variant. file_variant. shrink_size = file_size; break; case YAFFS_OBJECT_TYPE_HARDLINK: if (!is_unlinked) { in->variant. hardlink_variant. equiv_id = 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: if (oh) { in->variant. symlink_variant. alias = yaffs_clone_str(oh-> alias); if (!in->variant. symlink_variant. alias) alloc_failed = 1; } break; } } } } /* End of scanning for each chunk */ 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; } 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); } } yaffs_skip_rest_of_block(dev); if (alt_block_index) vfree(block_index); else kfree(block_index); /* 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); yaffs_release_temp_buffer(dev, chunk_data, __LINE__); if (alloc_failed) return YAFFS_FAIL; yaffs_trace(YAFFS_TRACE_SCAN, "yaffs2_scan_backwards ends"); return YAFFS_OK; }