- 根目录:
- fs
- yaffs2
- yaffs_yaffs2.c
/*
* 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;
}