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gfiber / kernel / windcharger / refs/heads/master / . / fs / yaffs2 / yaffs_guts.c
blob: 19dcb65d53b7ac92f8b65677ac0c3f5a4765490d [file] [log] [blame]
/*
* 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 "yportenv.h"
#include "yaffs_trace.h"
#include "yaffsinterface.h"
#include "yaffs_guts.h"
#include "yaffs_tagsvalidity.h"
#include "yaffs_getblockinfo.h"
#include "yaffs_tagscompat.h"
#include "yaffs_nand.h"
#include "yaffs_yaffs1.h"
#include "yaffs_yaffs2.h"
#include "yaffs_bitmap.h"
#include "yaffs_verify.h"
#include "yaffs_nand.h"
#include "yaffs_packedtags2.h"
#include "yaffs_nameval.h"
#include "yaffs_allocator.h"
/* Note YAFFS_GC_GOOD_ENOUGH must be <= YAFFS_GC_PASSIVE_THRESHOLD */
#define YAFFS_GC_GOOD_ENOUGH 2
#define YAFFS_GC_PASSIVE_THRESHOLD 4
#include "yaffs_ecc.h"
/* Robustification (if it ever comes about...) */
static void yaffs_retire_block(yaffs_dev_t *dev, int flash_block);
static void yaffs_handle_chunk_wr_error(yaffs_dev_t *dev, int nand_chunk,
int erasedOk);
static void yaffs_handle_chunk_wr_ok(yaffs_dev_t *dev, int nand_chunk,
const __u8 *data,
const yaffs_ext_tags *tags);
static void yaffs_handle_chunk_update(yaffs_dev_t *dev, int nand_chunk,
const yaffs_ext_tags *tags);
/* Other local prototypes */
static void yaffs_update_parent(yaffs_obj_t *obj);
static int yaffs_unlink_obj(yaffs_obj_t *obj);
static int yaffs_obj_cache_dirty(yaffs_obj_t *obj);
static int yaffs_write_new_chunk(yaffs_dev_t *dev,
const __u8 *buffer,
yaffs_ext_tags *tags,
int useReserve);
static yaffs_obj_t *yaffs_new_obj(yaffs_dev_t *dev, int number,
yaffs_obj_type type);
static int yaffs_apply_xattrib_mod(yaffs_obj_t *obj, char *buffer, yaffs_xattr_mod *xmod);
static void yaffs_remove_obj_from_dir(yaffs_obj_t *obj);
static int yaffs_check_structures(void);
static int yaffs_generic_obj_del(yaffs_obj_t *in);
static int yaffs_check_chunk_erased(struct yaffs_dev_s *dev,
int nand_chunk);
static int yaffs_unlink_worker(yaffs_obj_t *obj);
static int yaffs_tags_match(const yaffs_ext_tags *tags, int obj_id,
int chunkInObject);
static int yaffs_alloc_chunk(yaffs_dev_t *dev, int useReserve,
yaffs_block_info_t **blockUsedPtr);
static void yaffs_check_obj_details_loaded(yaffs_obj_t *in);
static void yaffs_invalidate_whole_cache(yaffs_obj_t *in);
static void yaffs_invalidate_chunk_cache(yaffs_obj_t *object, int chunk_id);
static int yaffs_find_chunk_in_file(yaffs_obj_t *in, int inode_chunk,
yaffs_ext_tags *tags);
static int yaffs_verify_chunk_written(yaffs_dev_t *dev,
int nand_chunk,
const __u8 *data,
yaffs_ext_tags *tags);
static void yaffs_load_name_from_oh(yaffs_dev_t *dev,YCHAR *name, const YCHAR *ohName, int bufferSize);
static void yaffs_load_oh_from_name(yaffs_dev_t *dev,YCHAR *ohName, const YCHAR *name);
/* Function to calculate chunk and offset */
static void yaffs_addr_to_chunk(yaffs_dev_t *dev, loff_t addr, int *chunkOut,
__u32 *offsetOut)
{
int chunk;
__u32 offset;
chunk = (__u32)(addr >> dev->chunk_shift);
if (dev->chunk_div == 1) {
/* easy power of 2 case */
offset = (__u32)(addr & dev->chunk_mask);
} else {
/* Non power-of-2 case */
loff_t chunkBase;
chunk /= dev->chunk_div;
chunkBase = ((loff_t)chunk) * dev->data_bytes_per_chunk;
offset = (__u32)(addr - chunkBase);
}
*chunkOut = chunk;
*offsetOut = offset;
}
/* Function to return the number of shifts for a power of 2 greater than or
* equal to the given number
* Note we don't try to cater for all possible numbers and this does not have to
* be hellishly efficient.
*/
static __u32 ShiftsGE(__u32 x)
{
int extraBits;
int nShifts;
nShifts = extraBits = 0;
while (x > 1) {
if (x & 1)
extraBits++;
x >>= 1;
nShifts++;
}
if (extraBits)
nShifts++;
return nShifts;
}
/* Function to return the number of shifts to get a 1 in bit 0
*/
static __u32 Shifts(__u32 x)
{
__u32 nShifts;
nShifts = 0;
if (!x)
return 0;
while (!(x&1)) {
x >>= 1;
nShifts++;
}
return nShifts;
}
/*
* Temporary buffer manipulations.
*/
static int yaffs_init_tmp_buffers(yaffs_dev_t *dev)
{
int i;
__u8 *buf = (__u8 *)1;
memset(dev->temp_buffer, 0, sizeof(dev->temp_buffer));
for (i = 0; buf && i < YAFFS_N_TEMP_BUFFERS; i++) {
dev->temp_buffer[i].line = 0; /* not in use */
dev->temp_buffer[i].buffer = buf =
YMALLOC_DMA(dev->param.total_bytes_per_chunk);
}
return buf ? YAFFS_OK : YAFFS_FAIL;
}
__u8 *yaffs_get_temp_buffer(yaffs_dev_t *dev, int line_no)
{
int i, j;
dev->temp_in_use++;
if (dev->temp_in_use > dev->max_temp)
dev->max_temp = dev->temp_in_use;
for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++) {
if (dev->temp_buffer[i].line == 0) {
dev->temp_buffer[i].line = line_no;
if ((i + 1) > dev->max_temp) {
dev->max_temp = i + 1;
for (j = 0; j <= i; j++)
dev->temp_buffer[j].max_line =
dev->temp_buffer[j].line;
}
return dev->temp_buffer[i].buffer;
}
}
T(YAFFS_TRACE_BUFFERS,
(TSTR("Out of temp buffers at line %d, other held by lines:"),
line_no));
for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++)
T(YAFFS_TRACE_BUFFERS, (TSTR(" %d "), dev->temp_buffer[i].line));
T(YAFFS_TRACE_BUFFERS, (TSTR(" " TENDSTR)));
/*
* If we got here then we have to allocate an unmanaged one
* This is not good.
*/
dev->unmanaged_buffer_allocs++;
return YMALLOC(dev->data_bytes_per_chunk);
}
void yaffs_release_temp_buffer(yaffs_dev_t *dev, __u8 *buffer,
int line_no)
{
int i;
dev->temp_in_use--;
for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++) {
if (dev->temp_buffer[i].buffer == buffer) {
dev->temp_buffer[i].line = 0;
return;
}
}
if (buffer) {
/* assume it is an unmanaged one. */
T(YAFFS_TRACE_BUFFERS,
(TSTR("Releasing unmanaged temp buffer in line %d" TENDSTR),
line_no));
YFREE(buffer);
dev->unmanaged_buffer_deallocs++;
}
}
/*
* Determine if we have a managed buffer.
*/
int yaffs_is_managed_tmp_buffer(yaffs_dev_t *dev, const __u8 *buffer)
{
int i;
for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++) {
if (dev->temp_buffer[i].buffer == buffer)
return 1;
}
for (i = 0; i < dev->param.n_caches; i++) {
if (dev->cache[i].data == buffer)
return 1;
}
if (buffer == dev->checkpt_buffer)
return 1;
T(YAFFS_TRACE_ALWAYS,
(TSTR("yaffs: unmaged buffer detected.\n" TENDSTR)));
return 0;
}
/*
* Verification code
*/
/*
* Simple hash function. Needs to have a reasonable spread
*/
static Y_INLINE int yaffs_hash_fn(int n)
{
n = abs(n);
return n % YAFFS_NOBJECT_BUCKETS;
}
/*
* Access functions to useful fake objects.
* Note that root might have a presence in NAND if permissions are set.
*/
yaffs_obj_t *yaffs_root(yaffs_dev_t *dev)
{
return dev->root_dir;
}
yaffs_obj_t *yaffs_lost_n_found(yaffs_dev_t *dev)
{
return dev->lost_n_found;
}
/*
* Erased NAND checking functions
*/
int yaffs_check_ff(__u8 *buffer, int n_bytes)
{
/* Horrible, slow implementation */
while (n_bytes--) {
if (*buffer != 0xFF)
return 0;
buffer++;
}
return 1;
}
static int yaffs_check_chunk_erased(struct yaffs_dev_s *dev,
int nand_chunk)
{
int retval = YAFFS_OK;
__u8 *data = yaffs_get_temp_buffer(dev, __LINE__);
yaffs_ext_tags tags;
int result;
result = yaffs_rd_chunk_tags_nand(dev, nand_chunk, data, &tags);
if (tags.ecc_result > YAFFS_ECC_RESULT_NO_ERROR)
retval = YAFFS_FAIL;
if (!yaffs_check_ff(data, dev->data_bytes_per_chunk) || tags.chunk_used) {
T(YAFFS_TRACE_NANDACCESS,
(TSTR("Chunk %d not erased" TENDSTR), nand_chunk));
retval = YAFFS_FAIL;
}
yaffs_release_temp_buffer(dev, data, __LINE__);
return retval;
}
static int yaffs_verify_chunk_written(yaffs_dev_t *dev,
int nand_chunk,
const __u8 *data,
yaffs_ext_tags *tags)
{
int retval = YAFFS_OK;
yaffs_ext_tags tempTags;
__u8 *buffer = yaffs_get_temp_buffer(dev,__LINE__);
int result;
result = yaffs_rd_chunk_tags_nand(dev,nand_chunk,buffer,&tempTags);
if(memcmp(buffer,data,dev->data_bytes_per_chunk) ||
tempTags.obj_id != tags->obj_id ||
tempTags.chunk_id != tags->chunk_id ||
tempTags.n_bytes != tags->n_bytes)
retval = YAFFS_FAIL;
yaffs_release_temp_buffer(dev, buffer, __LINE__);
return retval;
}
static int yaffs_write_new_chunk(struct yaffs_dev_s *dev,
const __u8 *data,
yaffs_ext_tags *tags,
int useReserve)
{
int attempts = 0;
int writeOk = 0;
int chunk;
yaffs2_checkpt_invalidate(dev);
do {
yaffs_block_info_t *bi = 0;
int erasedOk = 0;
chunk = yaffs_alloc_chunk(dev, useReserve, &bi);
if (chunk < 0) {
/* no space */
break;
}
/* First check this chunk is erased, if it needs
* checking. The checking policy (unless forced
* always on) is as follows:
*
* Check the first page we try to write in a block.
* If the check passes then we don't need to check any
* more. If the check fails, we check again...
* If the block has been erased, we don't need to check.
*
* However, if the block has been prioritised for gc,
* then we think there might be something odd about
* this block and stop using it.
*
* Rationale: We should only ever see chunks that have
* not been erased if there was a partially written
* chunk due to power loss. This checking policy should
* catch that case with very few checks and thus save a
* lot of checks that are most likely not needed.
*
* Mods to the above
* If an erase check fails or the write fails we skip the
* rest of the block.
*/
/* let's give it a try */
attempts++;
if(dev->param.always_check_erased)
bi->skip_erased_check = 0;
if (!bi->skip_erased_check) {
erasedOk = yaffs_check_chunk_erased(dev, chunk);
if (erasedOk != YAFFS_OK) {
T(YAFFS_TRACE_ERROR,
(TSTR("**>> yaffs chunk %d was not erased"
TENDSTR), chunk));
/* If not erased, delete this one,
* skip rest of block and
* try another chunk */
yaffs_chunk_del(dev,chunk,1,__LINE__);
yaffs_skip_rest_of_block(dev);
continue;
}
}
writeOk = yaffs_wr_chunk_tags_nand(dev, chunk,
data, tags);
if(!bi->skip_erased_check)
writeOk = yaffs_verify_chunk_written(dev, chunk, data, tags);
if (writeOk != YAFFS_OK) {
/* Clean up aborted write, skip to next block and
* try another chunk */
yaffs_handle_chunk_wr_error(dev, chunk, erasedOk);
continue;
}
bi->skip_erased_check = 1;
/* Copy the data into the robustification buffer */
yaffs_handle_chunk_wr_ok(dev, chunk, data, tags);
} while (writeOk != YAFFS_OK &&
(yaffs_wr_attempts <= 0 || attempts <= yaffs_wr_attempts));
if (!writeOk)
chunk = -1;
if (attempts > 1) {
T(YAFFS_TRACE_ERROR,
(TSTR("**>> yaffs write required %d attempts" TENDSTR),
attempts));
dev->n_retired_writes += (attempts - 1);
}
return chunk;
}
/*
* Block retiring for handling a broken block.
*/
static void yaffs_retire_block(yaffs_dev_t *dev, int flash_block)
{
yaffs_block_info_t *bi = yaffs_get_block_info(dev, flash_block);
yaffs2_checkpt_invalidate(dev);
yaffs2_clear_oldest_dirty_seq(dev,bi);
if (yaffs_mark_bad(dev, flash_block) != YAFFS_OK) {
if (yaffs_erase_block(dev, flash_block) != YAFFS_OK) {
T(YAFFS_TRACE_ALWAYS, (TSTR(
"yaffs: Failed to mark bad and erase block %d"
TENDSTR), flash_block));
} else {
yaffs_ext_tags tags;
int chunk_id = flash_block * dev->param.chunks_per_block;
__u8 *buffer = yaffs_get_temp_buffer(dev, __LINE__);
memset(buffer, 0xff, dev->data_bytes_per_chunk);
yaffs_init_tags(&tags);
tags.seq_number = YAFFS_SEQUENCE_BAD_BLOCK;
if (dev->param.write_chunk_tags_fn(dev, chunk_id -
dev->chunk_offset, buffer, &tags) != YAFFS_OK)
T(YAFFS_TRACE_ALWAYS, (TSTR("yaffs: Failed to "
TCONT("write bad block marker to block %d")
TENDSTR), flash_block));
yaffs_release_temp_buffer(dev, buffer, __LINE__);
}
}
bi->block_state = YAFFS_BLOCK_STATE_DEAD;
bi->gc_prioritise = 0;
bi->needs_retiring = 0;
dev->n_retired_blocks++;
}
/*
* Functions for robustisizing TODO
*
*/
static void yaffs_handle_chunk_wr_ok(yaffs_dev_t *dev, int nand_chunk,
const __u8 *data,
const yaffs_ext_tags *tags)
{
dev=dev;
nand_chunk=nand_chunk;
data=data;
tags=tags;
}
static void yaffs_handle_chunk_update(yaffs_dev_t *dev, int nand_chunk,
const yaffs_ext_tags *tags)
{
dev=dev;
nand_chunk=nand_chunk;
tags=tags;
}
void yaffs_handle_chunk_error(yaffs_dev_t *dev, yaffs_block_info_t *bi)
{
if (!bi->gc_prioritise) {
bi->gc_prioritise = 1;
dev->has_pending_prioritised_gc = 1;
bi->chunk_error_strikes++;
if (bi->chunk_error_strikes > 3) {
bi->needs_retiring = 1; /* Too many stikes, so retire this */
T(YAFFS_TRACE_ALWAYS, (TSTR("yaffs: Block struck out" TENDSTR)));
}
}
}
static void yaffs_handle_chunk_wr_error(yaffs_dev_t *dev, int nand_chunk,
int erasedOk)
{
int flash_block = nand_chunk / dev->param.chunks_per_block;
yaffs_block_info_t *bi = yaffs_get_block_info(dev, flash_block);
yaffs_handle_chunk_error(dev, bi);
if (erasedOk) {
/* Was an actual write failure, so mark the block for retirement */
bi->needs_retiring = 1;
T(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,
(TSTR("**>> Block %d needs retiring" TENDSTR), flash_block));
}
/* Delete the chunk */
yaffs_chunk_del(dev, nand_chunk, 1, __LINE__);
yaffs_skip_rest_of_block(dev);
}
/*---------------- Name handling functions ------------*/
static __u16 yaffs_calc_name_sum(const YCHAR *name)
{
__u16 sum = 0;
__u16 i = 1;
const YUCHAR *bname = (const YUCHAR *) name;
if (bname) {
while ((*bname) && (i < (YAFFS_MAX_NAME_LENGTH/2))) {
#ifdef CONFIG_YAFFS_CASE_INSENSITIVE
sum += yaffs_toupper(*bname) * i;
#else
sum += (*bname) * i;
#endif
i++;
bname++;
}
}
return sum;
}
void yaffs_set_obj_name(yaffs_obj_t *obj, const YCHAR *name)
{
#ifdef CONFIG_YAFFS_SHORT_NAMES_IN_RAM
memset(obj->short_name, 0, sizeof(YCHAR) * (YAFFS_SHORT_NAME_LENGTH+1));
if (name && yaffs_strnlen(name,YAFFS_SHORT_NAME_LENGTH+1) <= YAFFS_SHORT_NAME_LENGTH)
yaffs_strcpy(obj->short_name, name);
else
obj->short_name[0] = _Y('\0');
#endif
obj->sum = yaffs_calc_name_sum(name);
}
void yaffs_set_obj_name_from_oh(yaffs_obj_t *obj, const yaffs_obj_header *oh)
{
#ifdef CONFIG_YAFFS_AUTO_UNICODE
YCHAR tmpName[YAFFS_MAX_NAME_LENGTH+1];
memset(tmpName,0,sizeof(tmpName));
yaffs_load_name_from_oh(obj->my_dev,tmpName,oh->name,YAFFS_MAX_NAME_LENGTH+1);
yaffs_set_obj_name(obj,tmpName);
#else
yaffs_set_obj_name(obj,oh->name);
#endif
}
/*-------------------- TNODES -------------------
* List of spare tnodes
* The list is hooked together using the first pointer
* in the tnode.
*/
yaffs_tnode_t *yaffs_get_tnode(yaffs_dev_t *dev)
{
yaffs_tnode_t *tn = yaffs_alloc_raw_tnode(dev);
if (tn){
memset(tn, 0, dev->tnode_size);
dev->n_tnodes++;
}
dev->checkpoint_blocks_required = 0; /* force recalculation*/
return tn;
}
/* FreeTnode frees up a tnode and puts it back on the free list */
static void yaffs_free_tnode(yaffs_dev_t *dev, yaffs_tnode_t *tn)
{
yaffs_free_raw_tnode(dev,tn);
dev->n_tnodes--;
dev->checkpoint_blocks_required = 0; /* force recalculation*/
}
static void yaffs_deinit_tnodes_and_objs(yaffs_dev_t *dev)
{
yaffs_deinit_raw_tnodes_and_objs(dev);
dev->n_obj = 0;
dev->n_tnodes = 0;
}
void yaffs_load_tnode_0(yaffs_dev_t *dev, yaffs_tnode_t *tn, unsigned pos,
unsigned val)
{
__u32 *map = (__u32 *)tn;
__u32 bitInMap;
__u32 bitInWord;
__u32 wordInMap;
__u32 mask;
pos &= YAFFS_TNODES_LEVEL0_MASK;
val >>= dev->chunk_grp_bits;
bitInMap = pos * dev->tnode_width;
wordInMap = bitInMap / 32;
bitInWord = bitInMap & (32 - 1);
mask = dev->tnode_mask << bitInWord;
map[wordInMap] &= ~mask;
map[wordInMap] |= (mask & (val << bitInWord));
if (dev->tnode_width > (32 - bitInWord)) {
bitInWord = (32 - bitInWord);
wordInMap++;;
mask = dev->tnode_mask >> (/*dev->tnode_width -*/ bitInWord);
map[wordInMap] &= ~mask;
map[wordInMap] |= (mask & (val >> bitInWord));
}
}
__u32 yaffs_get_group_base(yaffs_dev_t *dev, yaffs_tnode_t *tn,
unsigned pos)
{
__u32 *map = (__u32 *)tn;
__u32 bitInMap;
__u32 bitInWord;
__u32 wordInMap;
__u32 val;
pos &= YAFFS_TNODES_LEVEL0_MASK;
bitInMap = pos * dev->tnode_width;
wordInMap = bitInMap / 32;
bitInWord = bitInMap & (32 - 1);
val = map[wordInMap] >> bitInWord;
if (dev->tnode_width > (32 - bitInWord)) {
bitInWord = (32 - bitInWord);
wordInMap++;;
val |= (map[wordInMap] << bitInWord);
}
val &= dev->tnode_mask;
val <<= dev->chunk_grp_bits;
return val;
}
/* ------------------- End of individual tnode manipulation -----------------*/
/* ---------Functions to manipulate the look-up tree (made up of tnodes) ------
* The look up tree is represented by the top tnode and the number of top_level
* in the tree. 0 means only the level 0 tnode is in the tree.
*/
/* FindLevel0Tnode finds the level 0 tnode, if one exists. */
yaffs_tnode_t *yaffs_find_tnode_0(yaffs_dev_t *dev,
yaffs_file_s *file_struct,
__u32 chunk_id)
{
yaffs_tnode_t *tn = file_struct->top;
__u32 i;
int requiredTallness;
int level = file_struct->top_level;
dev=dev;
/* Check sane level and chunk Id */
if (level < 0 || level > YAFFS_TNODES_MAX_LEVEL)
return NULL;
if (chunk_id > YAFFS_MAX_CHUNK_ID)
return NULL;
/* First check we're tall enough (ie enough top_level) */
i = chunk_id >> YAFFS_TNODES_LEVEL0_BITS;
requiredTallness = 0;
while (i) {
i >>= YAFFS_TNODES_INTERNAL_BITS;
requiredTallness++;
}
if (requiredTallness > file_struct->top_level)
return NULL; /* Not tall enough, so we can't find it */
/* Traverse down to level 0 */
while (level > 0 && tn) {
tn = tn->internal[(chunk_id >>
(YAFFS_TNODES_LEVEL0_BITS +
(level - 1) *
YAFFS_TNODES_INTERNAL_BITS)) &
YAFFS_TNODES_INTERNAL_MASK];
level--;
}
return tn;
}
/* AddOrFindLevel0Tnode finds the level 0 tnode if it exists, otherwise first expands the tree.
* This happens in two steps:
* 1. If the tree isn't tall enough, then make it taller.
* 2. Scan down the tree towards the level 0 tnode adding tnodes if required.
*
* Used when modifying the tree.
*
* If the tn argument is NULL, then a fresh tnode will be added otherwise the specified tn will
* be plugged into the ttree.
*/
yaffs_tnode_t *yaffs_add_find_tnode_0(yaffs_dev_t *dev,
yaffs_file_s *file_struct,
__u32 chunk_id,
yaffs_tnode_t *passed_tn)
{
int requiredTallness;
int i;
int l;
yaffs_tnode_t *tn;
__u32 x;
/* Check sane level and page Id */
if (file_struct->top_level < 0 || file_struct->top_level > YAFFS_TNODES_MAX_LEVEL)
return NULL;
if (chunk_id > YAFFS_MAX_CHUNK_ID)
return NULL;
/* First check we're tall enough (ie enough top_level) */
x = chunk_id >> YAFFS_TNODES_LEVEL0_BITS;
requiredTallness = 0;
while (x) {
x >>= YAFFS_TNODES_INTERNAL_BITS;
requiredTallness++;
}
if (requiredTallness > file_struct->top_level) {
/* Not tall enough, gotta make the tree taller */
for (i = file_struct->top_level; i < requiredTallness; i++) {
tn = yaffs_get_tnode(dev);
if (tn) {
tn->internal[0] = file_struct->top;
file_struct->top = tn;
file_struct->top_level++;
} else {
T(YAFFS_TRACE_ERROR,
(TSTR("yaffs: no more tnodes" TENDSTR)));
return NULL;
}
}
}
/* Traverse down to level 0, adding anything we need */
l = file_struct->top_level;
tn = file_struct->top;
if (l > 0) {
while (l > 0 && tn) {
x = (chunk_id >>
(YAFFS_TNODES_LEVEL0_BITS +
(l - 1) * YAFFS_TNODES_INTERNAL_BITS)) &
YAFFS_TNODES_INTERNAL_MASK;
if ((l > 1) && !tn->internal[x]) {
/* Add missing non-level-zero tnode */
tn->internal[x] = yaffs_get_tnode(dev);
if(!tn->internal[x])
return NULL;
} else if (l == 1) {
/* Looking from level 1 at level 0 */
if (passed_tn) {
/* If we already have one, then release it.*/
if (tn->internal[x])
yaffs_free_tnode(dev, tn->internal[x]);
tn->internal[x] = passed_tn;
} else if (!tn->internal[x]) {
/* Don't have one, none passed in */
tn->internal[x] = yaffs_get_tnode(dev);
if(!tn->internal[x])
return NULL;
}
}
tn = tn->internal[x];
l--;
}
} else {
/* top is level 0 */
if (passed_tn) {
memcpy(tn, passed_tn, (dev->tnode_width * YAFFS_NTNODES_LEVEL0)/8);
yaffs_free_tnode(dev, passed_tn);
}
}
return tn;
}
static int yaffs_find_chunk_in_group(yaffs_dev_t *dev, int theChunk,
yaffs_ext_tags *tags, int obj_id,
int inode_chunk)
{
int j;
for (j = 0; theChunk && j < dev->chunk_grp_size; j++) {
if (yaffs_check_chunk_bit(dev, theChunk / dev->param.chunks_per_block,
theChunk % dev->param.chunks_per_block)) {
if(dev->chunk_grp_size == 1)
return theChunk;
else {
yaffs_rd_chunk_tags_nand(dev, theChunk, NULL,
tags);
if (yaffs_tags_match(tags, obj_id, inode_chunk)) {
/* found it; */
return theChunk;
}
}
}
theChunk++;
}
return -1;
}
#if 0
/* Experimental code not being used yet. Might speed up file deletion */
/* DeleteWorker scans backwards through the tnode tree and deletes all the
* chunks and tnodes in the file.
* Returns 1 if the tree was deleted.
* Returns 0 if it stopped early due to hitting the limit and the delete is incomplete.
*/
static int yaffs_del_worker(yaffs_obj_t *in, yaffs_tnode_t *tn, __u32 level,
int chunk_offset, int *limit)
{
int i;
int inode_chunk;
int theChunk;
yaffs_ext_tags tags;
int foundChunk;
yaffs_dev_t *dev = in->my_dev;
int allDone = 1;
if (tn) {
if (level > 0) {
for (i = YAFFS_NTNODES_INTERNAL - 1; allDone && i >= 0;
i--) {
if (tn->internal[i]) {
if (limit && (*limit) < 0) {
allDone = 0;
} else {
allDone =
yaffs_del_worker(in,
tn->
internal
[i],
level -
1,
(chunk_offset
<<
YAFFS_TNODES_INTERNAL_BITS)
+ i,
limit);
}
if (allDone) {
yaffs_free_tnode(dev,
tn->
internal[i]);
tn->internal[i] = NULL;
}
}
}
return (allDone) ? 1 : 0;
} else if (level == 0) {
int hitLimit = 0;
for (i = YAFFS_NTNODES_LEVEL0 - 1; i >= 0 && !hitLimit;
i--) {
theChunk = yaffs_get_group_base(dev, tn, i);
if (theChunk) {
inode_chunk = (chunk_offset <<
YAFFS_TNODES_LEVEL0_BITS) + i;
foundChunk =
yaffs_find_chunk_in_group(dev,
theChunk,
&tags,
in->obj_id,
inode_chunk);
if (foundChunk > 0) {
yaffs_chunk_del(dev,
foundChunk, 1,
__LINE__);
in->n_data_chunks--;
if (limit) {
*limit = *limit - 1;
if (*limit <= 0)
hitLimit = 1;
}
}
yaffs_load_tnode_0(dev, tn, i, 0);
}
}
return (i < 0) ? 1 : 0;
}
}
return 1;
}
#endif
static void yaffs_soft_del_chunk(yaffs_dev_t *dev, int chunk)
{
yaffs_block_info_t *theBlock;
unsigned block_no;
T(YAFFS_TRACE_DELETION, (TSTR("soft delete chunk %d" TENDSTR), chunk));
block_no = chunk / dev->param.chunks_per_block;
theBlock = yaffs_get_block_info(dev, block_no);
if (theBlock) {
theBlock->soft_del_pages++;
dev->n_free_chunks++;
yaffs2_update_oldest_dirty_seq(dev, block_no, theBlock);
}
}
/* SoftDeleteWorker scans backwards through the tnode tree and soft deletes all the chunks in the file.
* All soft deleting does is increment the block's softdelete count and pulls the chunk out
* of the tnode.
* Thus, essentially this is the same as DeleteWorker except that the chunks are soft deleted.
*/
static int yaffs_soft_del_worker(yaffs_obj_t *in, yaffs_tnode_t *tn,
__u32 level, int chunk_offset)
{
int i;
int theChunk;
int allDone = 1;
yaffs_dev_t *dev = in->my_dev;
if (tn) {
if (level > 0) {
for (i = YAFFS_NTNODES_INTERNAL - 1; allDone && i >= 0;
i--) {
if (tn->internal[i]) {
allDone =
yaffs_soft_del_worker(in,
tn->
internal[i],
level - 1,
(chunk_offset
<<
YAFFS_TNODES_INTERNAL_BITS)
+ i);
if (allDone) {
yaffs_free_tnode(dev,
tn->
internal[i]);
tn->internal[i] = NULL;
} else {
/* Hoosterman... how could this happen? */
}
}
}
return (allDone) ? 1 : 0;
} else if (level == 0) {
for (i = YAFFS_NTNODES_LEVEL0 - 1; i >= 0; i--) {
theChunk = yaffs_get_group_base(dev, tn, i);
if (theChunk) {
/* Note this does not find the real chunk, only the chunk group.
* We make an assumption that a chunk group is not larger than
* a block.
*/
yaffs_soft_del_chunk(dev, theChunk);
yaffs_load_tnode_0(dev, tn, i, 0);
}
}
return 1;
}
}
return 1;
}
static void yaffs_soft_del_file(yaffs_obj_t *obj)
{
if (obj->deleted &&
obj->variant_type == YAFFS_OBJECT_TYPE_FILE && !obj->soft_del) {
if (obj->n_data_chunks <= 0) {
/* Empty file with no duplicate object headers, just delete it immediately */
yaffs_free_tnode(obj->my_dev,
obj->variant.file_variant.top);
obj->variant.file_variant.top = NULL;
T(YAFFS_TRACE_TRACING,
(TSTR("yaffs: Deleting empty file %d" TENDSTR),
obj->obj_id));
yaffs_generic_obj_del(obj);
} else {
yaffs_soft_del_worker(obj,
obj->variant.file_variant.top,
obj->variant.file_variant.
top_level, 0);
obj->soft_del = 1;
}
}
}
/* Pruning removes any part of the file structure tree that is beyond the
* bounds of the file (ie that does not point to chunks).
*
* A file should only get pruned when its size is reduced.
*
* Before pruning, the chunks must be pulled from the tree and the
* level 0 tnode entries must be zeroed out.
* Could also use this for file deletion, but that's probably better handled
* by a special case.
*
* This function is recursive. For levels > 0 the function is called again on
* any sub-tree. For level == 0 we just check if the sub-tree has data.
* If there is no data in a subtree then it is pruned.
*/
static yaffs_tnode_t *yaffs_prune_worker(yaffs_dev_t *dev, yaffs_tnode_t *tn,
__u32 level, int del0)
{
int i;
int hasData;
if (tn) {
hasData = 0;
if(level > 0){
for (i = 0; i < YAFFS_NTNODES_INTERNAL; i++) {
if (tn->internal[i]) {
tn->internal[i] =
yaffs_prune_worker(dev, tn->internal[i],
level - 1,
(i == 0) ? del0 : 1);
}
if (tn->internal[i])
hasData++;
}
} else {
int tnode_size_u32 = dev->tnode_size/sizeof(__u32);
__u32 *map = (__u32 *)tn;
for(i = 0; !hasData && i < tnode_size_u32; i++){
if(map[i])
hasData++;
}
}
if (hasData == 0 && del0) {
/* Free and return NULL */
yaffs_free_tnode(dev, tn);
tn = NULL;
}
}
return tn;
}
static int yaffs_prune_tree(yaffs_dev_t *dev,
yaffs_file_s *file_struct)
{
int i;
int hasData;
int done = 0;
yaffs_tnode_t *tn;
if (file_struct->top_level > 0) {
file_struct->top =
yaffs_prune_worker(dev, file_struct->top, file_struct->top_level, 0);
/* Now we have a tree with all the non-zero branches NULL but the height
* is the same as it was.
* Let's see if we can trim internal tnodes to shorten the tree.
* We can do this if only the 0th element in the tnode is in use
* (ie all the non-zero are NULL)
*/
while (file_struct->top_level && !done) {
tn = file_struct->top;
hasData = 0;
for (i = 1; i < YAFFS_NTNODES_INTERNAL; i++) {
if (tn->internal[i])
hasData++;
}
if (!hasData) {
file_struct->top = tn->internal[0];
file_struct->top_level--;
yaffs_free_tnode(dev, tn);
} else {
done = 1;
}
}
}
return YAFFS_OK;
}
/*-------------------- End of File Structure functions.-------------------*/
/* AllocateEmptyObject gets us a clean Object. Tries to make allocate more if we run out */
static yaffs_obj_t *yaffs_alloc_empty_obj(yaffs_dev_t *dev)
{
yaffs_obj_t *obj = yaffs_alloc_raw_obj(dev);
if (obj) {
dev->n_obj++;
/* Now sweeten it up... */
memset(obj, 0, sizeof(yaffs_obj_t));
obj->being_created = 1;
obj->my_dev = dev;
obj->hdr_chunk = 0;
obj->variant_type = YAFFS_OBJECT_TYPE_UNKNOWN;
YINIT_LIST_HEAD(&(obj->hard_links));
YINIT_LIST_HEAD(&(obj->hash_link));
YINIT_LIST_HEAD(&obj->siblings);
/* Now make the directory sane */
if (dev->root_dir) {
obj->parent = dev->root_dir;
ylist_add(&(obj->siblings), &dev->root_dir->variant.dir_variant.children);
}
/* Add it to the lost and found directory.
* NB Can't put root or lostNFound in lostNFound so
* check if lostNFound exists first
*/
if (dev->lost_n_found)
yaffs_add_obj_to_dir(dev->lost_n_found, obj);
obj->being_created = 0;
}
dev->checkpoint_blocks_required = 0; /* force recalculation*/
return obj;
}
static yaffs_obj_t *yaffs_create_fake_dir(yaffs_dev_t *dev, int number,
__u32 mode)
{
yaffs_obj_t *obj =
yaffs_new_obj(dev, number, YAFFS_OBJECT_TYPE_DIRECTORY);
if (obj) {
obj->fake = 1; /* it is fake so it might have no NAND presence... */
obj->rename_allowed = 0; /* ... and we're not allowed to rename it... */
obj->unlink_allowed = 0; /* ... or unlink it */
obj->deleted = 0;
obj->unlinked = 0;
obj->yst_mode = mode;
obj->my_dev = dev;
obj->hdr_chunk = 0; /* Not a valid chunk. */
}
return obj;
}
static void yaffs_unhash_obj(yaffs_obj_t *obj)
{
int bucket;
yaffs_dev_t *dev = obj->my_dev;
/* If it is still linked into the bucket list, free from the list */
if (!ylist_empty(&obj->hash_link)) {
ylist_del_init(&obj->hash_link);
bucket = yaffs_hash_fn(obj->obj_id);
dev->obj_bucket[bucket].count--;
}
}
/* FreeObject frees up a Object and puts it back on the free list */
static void yaffs_free_obj(yaffs_obj_t *obj)
{
yaffs_dev_t *dev = obj->my_dev;
T(YAFFS_TRACE_OS, (TSTR("FreeObject %p inode %p"TENDSTR), obj, obj->my_inode));
if (!obj)
YBUG();
if (obj->parent)
YBUG();
if (!ylist_empty(&obj->siblings))
YBUG();
if (obj->my_inode) {
/* We're still hooked up to a cached inode.
* Don't delete now, but mark for later deletion
*/
obj->defered_free = 1;
return;
}
yaffs_unhash_obj(obj);
yaffs_free_raw_obj(dev,obj);
dev->n_obj--;
dev->checkpoint_blocks_required = 0; /* force recalculation*/
}
void yaffs_handle_defered_free(yaffs_obj_t *obj)
{
if (obj->defered_free)
yaffs_free_obj(obj);
}
static void yaffs_init_tnodes_and_objs(yaffs_dev_t *dev)
{
int i;
dev->n_obj = 0;
dev->n_tnodes = 0;
yaffs_init_raw_tnodes_and_objs(dev);
for (i = 0; i < YAFFS_NOBJECT_BUCKETS; i++) {
YINIT_LIST_HEAD(&dev->obj_bucket[i].list);
dev->obj_bucket[i].count = 0;
}
}
static int yaffs_find_nice_bucket(yaffs_dev_t *dev)
{
int i;
int l = 999;
int lowest = 999999;
/* Search for the shortest list or one that
* isn't too long.
*/
for (i = 0; i < 10 && lowest > 4; i++) {
dev->bucket_finder++;
dev->bucket_finder %= YAFFS_NOBJECT_BUCKETS;
if (dev->obj_bucket[dev->bucket_finder].count < lowest) {
lowest = dev->obj_bucket[dev->bucket_finder].count;
l = dev->bucket_finder;
}
}
return l;
}
static int yaffs_new_obj_id(yaffs_dev_t *dev)
{
int bucket = yaffs_find_nice_bucket(dev);
/* Now find an object value that has not already been taken
* by scanning the list.
*/
int found = 0;
struct ylist_head *i;
__u32 n = (__u32) bucket;
/* yaffs_check_obj_hash_sane(); */
while (!found) {
found = 1;
n += YAFFS_NOBJECT_BUCKETS;
if (1 || dev->obj_bucket[bucket].count > 0) {
ylist_for_each(i, &dev->obj_bucket[bucket].list) {
/* If there is already one in the list */
if (i && ylist_entry(i, yaffs_obj_t,
hash_link)->obj_id == n) {
found = 0;
}
}
}
}
return n;
}
static void yaffs_hash_obj(yaffs_obj_t *in)
{
int bucket = yaffs_hash_fn(in->obj_id);
yaffs_dev_t *dev = in->my_dev;
ylist_add(&in->hash_link, &dev->obj_bucket[bucket].list);
dev->obj_bucket[bucket].count++;
}
yaffs_obj_t *yaffs_find_by_number(yaffs_dev_t *dev, __u32 number)
{
int bucket = yaffs_hash_fn(number);
struct ylist_head *i;
yaffs_obj_t *in;
ylist_for_each(i, &dev->obj_bucket[bucket].list) {
/* Look if it is in the list */
if (i) {
in = ylist_entry(i, yaffs_obj_t, hash_link);
if (in->obj_id == number) {
/* Don't tell the VFS about this one if it is defered free */
if (in->defered_free)
return NULL;
return in;
}
}
}
return NULL;
}
yaffs_obj_t *yaffs_new_obj(yaffs_dev_t *dev, int number,
yaffs_obj_type type)
{
yaffs_obj_t *theObject=NULL;
yaffs_tnode_t *tn = NULL;
if (number < 0)
number = yaffs_new_obj_id(dev);
if (type == YAFFS_OBJECT_TYPE_FILE) {
tn = yaffs_get_tnode(dev);
if (!tn)
return NULL;
}
theObject = yaffs_alloc_empty_obj(dev);
if (!theObject){
if(tn)
yaffs_free_tnode(dev,tn);
return NULL;
}
if (theObject) {
theObject->fake = 0;
theObject->rename_allowed = 1;
theObject->unlink_allowed = 1;
theObject->obj_id = number;
yaffs_hash_obj(theObject);
theObject->variant_type = type;
#ifdef CONFIG_YAFFS_WINCE
yfsd_win_file_time_now(theObject->win_atime);
theObject->win_ctime[0] = theObject->win_mtime[0] =
theObject->win_atime[0];
theObject->win_ctime[1] = theObject->win_mtime[1] =
theObject->win_atime[1];
#else
theObject->yst_atime = theObject->yst_mtime =
theObject->yst_ctime = Y_CURRENT_TIME;
#endif
switch (type) {
case YAFFS_OBJECT_TYPE_FILE:
theObject->variant.file_variant.file_size = 0;
theObject->variant.file_variant.scanned_size = 0;
theObject->variant.file_variant.shrink_size = 0xFFFFFFFF; /* max __u32 */
theObject->variant.file_variant.top_level = 0;
theObject->variant.file_variant.top = tn;
break;
case YAFFS_OBJECT_TYPE_DIRECTORY:
YINIT_LIST_HEAD(&theObject->variant.dir_variant.
children);
YINIT_LIST_HEAD(&theObject->variant.dir_variant.
dirty);
break;
case YAFFS_OBJECT_TYPE_SYMLINK:
case YAFFS_OBJECT_TYPE_HARDLINK:
case YAFFS_OBJECT_TYPE_SPECIAL:
/* No action required */
break;
case YAFFS_OBJECT_TYPE_UNKNOWN:
/* todo this should not happen */
break;
}
}
return theObject;
}
yaffs_obj_t *yaffs_find_or_create_by_number(yaffs_dev_t *dev,
int number,
yaffs_obj_type type)
{
yaffs_obj_t *theObject = NULL;
if (number > 0)
theObject = yaffs_find_by_number(dev, number);
if (!theObject)
theObject = yaffs_new_obj(dev, number, type);
return theObject;
}
YCHAR *yaffs_clone_str(const YCHAR *str)
{
YCHAR *newStr = NULL;
int len;
if (!str)
str = _Y("");
len = yaffs_strnlen(str,YAFFS_MAX_ALIAS_LENGTH);
newStr = YMALLOC((len + 1) * sizeof(YCHAR));
if (newStr){
yaffs_strncpy(newStr, str,len);
newStr[len] = 0;
}
return newStr;
}
/*
* Mknod (create) a new object.
* equiv_obj only has meaning for a hard link;
* aliasString only has meaning for a symlink.
* rdev only has meaning for devices (a subset of special objects)
*/
static yaffs_obj_t *yaffs_create_obj(yaffs_obj_type type,
yaffs_obj_t *parent,
const YCHAR *name,
__u32 mode,
__u32 uid,
__u32 gid,
yaffs_obj_t *equiv_obj,
const YCHAR *aliasString, __u32 rdev)
{
yaffs_obj_t *in;
YCHAR *str = NULL;
yaffs_dev_t *dev = parent->my_dev;
/* Check if the entry exists. If it does then fail the call since we don't want a dup.*/
if (yaffs_find_by_name(parent, name))
return NULL;
if (type == YAFFS_OBJECT_TYPE_SYMLINK) {
str = yaffs_clone_str(aliasString);
if (!str)
return NULL;
}
in = yaffs_new_obj(dev, -1, type);
if (!in){
if(str)
YFREE(str);
return NULL;
}
if (in) {
in->hdr_chunk = 0;
in->valid = 1;
in->variant_type = type;
in->yst_mode = mode;
#ifdef CONFIG_YAFFS_WINCE
yfsd_win_file_time_now(in->win_atime);
in->win_ctime[0] = in->win_mtime[0] = in->win_atime[0];
in->win_ctime[1] = in->win_mtime[1] = in->win_atime[1];
#else
in->yst_atime = in->yst_mtime = in->yst_ctime = Y_CURRENT_TIME;
in->yst_rdev = rdev;
in->yst_uid = uid;
in->yst_gid = gid;
#endif
in->n_data_chunks = 0;
yaffs_set_obj_name(in, name);
in->dirty = 1;
yaffs_add_obj_to_dir(parent, in);
in->my_dev = parent->my_dev;
switch (type) {
case YAFFS_OBJECT_TYPE_SYMLINK:
in->variant.symlink_variant.alias = str;
break;
case YAFFS_OBJECT_TYPE_HARDLINK:
in->variant.hardlink_variant.equiv_obj =
equiv_obj;
in->variant.hardlink_variant.equiv_id =
equiv_obj->obj_id;
ylist_add(&in->hard_links, &equiv_obj->hard_links);
break;
case YAFFS_OBJECT_TYPE_FILE:
case YAFFS_OBJECT_TYPE_DIRECTORY:
case YAFFS_OBJECT_TYPE_SPECIAL:
case YAFFS_OBJECT_TYPE_UNKNOWN:
/* do nothing */
break;
}
if (yaffs_update_oh(in, name, 0, 0, 0, NULL) < 0) {
/* Could not create the object header, fail the creation */
yaffs_del_obj(in);
in = NULL;
}
yaffs_update_parent(parent);
}
return in;
}
yaffs_obj_t *yaffs_create_file(yaffs_obj_t *parent, const YCHAR *name,
__u32 mode, __u32 uid, __u32 gid)
{
return yaffs_create_obj(YAFFS_OBJECT_TYPE_FILE, parent, name, mode,
uid, gid, NULL, NULL, 0);
}
yaffs_obj_t *yaffs_create_dir(yaffs_obj_t *parent, const YCHAR *name,
__u32 mode, __u32 uid, __u32 gid)
{
return yaffs_create_obj(YAFFS_OBJECT_TYPE_DIRECTORY, parent, name,
mode, uid, gid, NULL, NULL, 0);
}
yaffs_obj_t *yaffs_create_special(yaffs_obj_t *parent, const YCHAR *name,
__u32 mode, __u32 uid, __u32 gid, __u32 rdev)
{
return yaffs_create_obj(YAFFS_OBJECT_TYPE_SPECIAL, parent, name, mode,
uid, gid, NULL, NULL, rdev);
}
yaffs_obj_t *yaffs_create_symlink(yaffs_obj_t *parent, const YCHAR *name,
__u32 mode, __u32 uid, __u32 gid,
const YCHAR *alias)
{
return yaffs_create_obj(YAFFS_OBJECT_TYPE_SYMLINK, parent, name, mode,
uid, gid, NULL, alias, 0);
}
/* yaffs_link_obj returns the object id of the equivalent object.*/
yaffs_obj_t *yaffs_link_obj(yaffs_obj_t *parent, const YCHAR *name,
yaffs_obj_t *equiv_obj)
{
/* Get the real object in case we were fed a hard link as an equivalent object */
equiv_obj = yaffs_get_equivalent_obj(equiv_obj);
if (yaffs_create_obj
(YAFFS_OBJECT_TYPE_HARDLINK, parent, name, 0, 0, 0,
equiv_obj, NULL, 0)) {
return equiv_obj;
} else {
return NULL;
}
}
static int yaffs_change_obj_name(yaffs_obj_t *obj, yaffs_obj_t *new_dir,
const YCHAR *new_name, int force, int shadows)
{
int unlinkOp;
int deleteOp;
yaffs_obj_t *existingTarget;
if (new_dir == NULL)
new_dir = obj->parent; /* use the old directory */
if (new_dir->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY) {
T(YAFFS_TRACE_ALWAYS,
(TSTR
("tragedy: yaffs_change_obj_name: new_dir is not a directory"
TENDSTR)));
YBUG();
}
/* TODO: Do we need this different handling for YAFFS2 and YAFFS1?? */
// if (obj->my_dev->param.is_yaffs2)
unlinkOp = (new_dir == obj->my_dev->unlinked_dir);
/* else
unlinkOp = (new_dir == obj->my_dev->unlinked_dir
&& obj->variant_type == YAFFS_OBJECT_TYPE_FILE); */
deleteOp = (new_dir == obj->my_dev->del_dir);
existingTarget = yaffs_find_by_name(new_dir, new_name);
/* If the object is a file going into the unlinked directory,
* then it is OK to just stuff it in since duplicate names are allowed.
* else only proceed if the new name does not exist and if we're putting
* it into a directory.
*/
if ((unlinkOp ||
deleteOp ||
force ||
(shadows > 0) ||
!existingTarget) &&
new_dir->variant_type == YAFFS_OBJECT_TYPE_DIRECTORY) {
yaffs_set_obj_name(obj, new_name);
obj->dirty = 1;
yaffs_add_obj_to_dir(new_dir, obj);
if (unlinkOp)
obj->unlinked = 1;
/* If it is a deletion then we mark it as a shrink for gc purposes. */
if (yaffs_update_oh(obj, new_name, 0, deleteOp, shadows, NULL) >= 0)
return YAFFS_OK;
}
return YAFFS_FAIL;
}
int yaffs_rename_obj(yaffs_obj_t *old_dir, const YCHAR *old_name,
yaffs_obj_t *new_dir, const YCHAR *new_name)
{
yaffs_obj_t *obj = NULL;
yaffs_obj_t *existingTarget = NULL;
int force = 0;
int result;
yaffs_dev_t *dev;
if (!old_dir || old_dir->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY)
YBUG();
if (!new_dir || new_dir->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY)
YBUG();
dev = old_dir->my_dev;
#ifdef CONFIG_YAFFS_CASE_INSENSITIVE
/* Special case for case insemsitive systems (eg. WinCE).
* While look-up is case insensitive, the name isn't.
* Therefore we might want to change x.txt to X.txt
*/
if (old_dir == new_dir && yaffs_strcmp(old_name, new_name) == 0)
force = 1;
#endif
if(yaffs_strnlen(new_name,YAFFS_MAX_NAME_LENGTH+1) > YAFFS_MAX_NAME_LENGTH)
/* ENAMETOOLONG */
return YAFFS_FAIL;
obj = yaffs_find_by_name(old_dir, old_name);
if (obj && obj->rename_allowed) {
/* Now do the handling for an existing target, if there is one */
existingTarget = yaffs_find_by_name(new_dir, new_name);
if (existingTarget &&
existingTarget->variant_type == YAFFS_OBJECT_TYPE_DIRECTORY &&
!ylist_empty(&existingTarget->variant.dir_variant.children)) {
/* There is a target that is a non-empty directory, so we fail */
return YAFFS_FAIL; /* EEXIST or ENOTEMPTY */
} else if (existingTarget && existingTarget != obj) {
/* Nuke the target first, using shadowing,
* but only if it isn't the same object.
*
* Note we must disable gc otherwise it can mess up the shadowing.
*
*/
dev->gc_disable=1;
yaffs_change_obj_name(obj, new_dir, new_name, force,
existingTarget->obj_id);
existingTarget->is_shadowed = 1;
yaffs_unlink_obj(existingTarget);
dev->gc_disable=0;
}
result = yaffs_change_obj_name(obj, new_dir, new_name, 1, 0);
yaffs_update_parent(old_dir);
if(new_dir != old_dir)
yaffs_update_parent(new_dir);
return result;
}
return YAFFS_FAIL;
}
/*------------------------- Block Management and Page Allocation ----------------*/
static int yaffs_init_blocks(yaffs_dev_t *dev)
{
int nBlocks = dev->internal_end_block - dev->internal_start_block + 1;
dev->block_info = NULL;
dev->chunk_bits = NULL;
dev->alloc_block = -1; /* force it to get a new one */
/* If the first allocation strategy fails, thry the alternate one */
dev->block_info = YMALLOC(nBlocks * sizeof(yaffs_block_info_t));
if (!dev->block_info) {
dev->block_info = YMALLOC_ALT(nBlocks * sizeof(yaffs_block_info_t));
dev->block_info_alt = 1;
} else
dev->block_info_alt = 0;
if (dev->block_info) {
/* Set up dynamic blockinfo stuff. */
dev->chunk_bit_stride = (dev->param.chunks_per_block + 7) / 8; /* round up bytes */
dev->chunk_bits = YMALLOC(dev->chunk_bit_stride * nBlocks);
if (!dev->chunk_bits) {
dev->chunk_bits = YMALLOC_ALT(dev->chunk_bit_stride * nBlocks);
dev->chunk_bits_alt = 1;
} else
dev->chunk_bits_alt = 0;
}
if (dev->block_info && dev->chunk_bits) {
memset(dev->block_info, 0, nBlocks * sizeof(yaffs_block_info_t));
memset(dev->chunk_bits, 0, dev->chunk_bit_stride * nBlocks);
return YAFFS_OK;
}
return YAFFS_FAIL;
}
static void yaffs_deinit_blocks(yaffs_dev_t *dev)
{
if (dev->block_info_alt && dev->block_info)
YFREE_ALT(dev->block_info);
else if (dev->block_info)
YFREE(dev->block_info);
dev->block_info_alt = 0;
dev->block_info = NULL;
if (dev->chunk_bits_alt && dev->chunk_bits)
YFREE_ALT(dev->chunk_bits);
else if (dev->chunk_bits)
YFREE(dev->chunk_bits);
dev->chunk_bits_alt = 0;
dev->chunk_bits = NULL;
}
void yaffs_block_became_dirty(yaffs_dev_t *dev, int block_no)
{
yaffs_block_info_t *bi = yaffs_get_block_info(dev, block_no);
int erasedOk = 0;
/* If the block is still healthy erase it and mark as clean.
* If the block has had a data failure, then retire it.
*/
T(YAFFS_TRACE_GC | YAFFS_TRACE_ERASE,
(TSTR("yaffs_block_became_dirty block %d state %d %s"TENDSTR),
block_no, bi->block_state, (bi->needs_retiring) ? "needs retiring" : ""));
yaffs2_clear_oldest_dirty_seq(dev,bi);
bi->block_state = YAFFS_BLOCK_STATE_DIRTY;
/* If this is the block being garbage collected then stop gc'ing this block */
if(block_no == dev->gc_block)
dev->gc_block = 0;
/* If this block is currently the best candidate for gc then drop as a candidate */
if(block_no == dev->gc_dirtiest){
dev->gc_dirtiest = 0;
dev->gc_pages_in_use = 0;
}
if (!bi->needs_retiring) {
yaffs2_checkpt_invalidate(dev);
erasedOk = yaffs_erase_block(dev, block_no);
if (!erasedOk) {
dev->n_erase_failures++;
T(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,
(TSTR("**>> Erasure failed %d" TENDSTR), block_no));
}
}
if (erasedOk &&
((yaffs_trace_mask & YAFFS_TRACE_ERASE) || !yaffs_skip_verification(dev))) {
int i;
for (i = 0; i < dev->param.chunks_per_block; i++) {
if (!yaffs_check_chunk_erased
(dev, block_no * dev->param.chunks_per_block + i)) {
T(YAFFS_TRACE_ERROR,
(TSTR
(">>Block %d erasure supposedly OK, but chunk %d not erased"
TENDSTR), block_no, i));
}
}
}
if (erasedOk) {
/* Clean it up... */
bi->block_state = YAFFS_BLOCK_STATE_EMPTY;
bi->seq_number = 0;
dev->n_erased_blocks++;
bi->pages_in_use = 0;
bi->soft_del_pages = 0;
bi->has_shrink_hdr = 0;
bi->skip_erased_check = 1; /* This is clean, so no need to check */
bi->gc_prioritise = 0;
yaffs_clear_chunk_bits(dev, block_no);
T(YAFFS_TRACE_ERASE,
(TSTR("Erased block %d" TENDSTR), block_no));
} else {
dev->n_free_chunks -= dev->param.chunks_per_block; /* We lost a block of free space */
yaffs_retire_block(dev, block_no);
T(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,
(TSTR("**>> Block %d retired" TENDSTR), block_no));
}
}
static int yaffs_find_alloc_block(yaffs_dev_t *dev)
{
int i;
yaffs_block_info_t *bi;
if (dev->n_erased_blocks < 1) {
/* Hoosterman we've got a problem.
* Can't get space to gc
*/
T(YAFFS_TRACE_ERROR,
(TSTR("yaffs tragedy: no more erased blocks" TENDSTR)));
return -1;
}
/* Find an empty block. */
for (i = dev->internal_start_block; i <= dev->internal_end_block; i++) {
dev->alloc_block_finder++;
if (dev->alloc_block_finder < dev->internal_start_block
|| dev->alloc_block_finder > dev->internal_end_block) {
dev->alloc_block_finder = dev->internal_start_block;
}
bi = yaffs_get_block_info(dev, dev->alloc_block_finder);
if (bi->block_state == YAFFS_BLOCK_STATE_EMPTY) {
bi->block_state = YAFFS_BLOCK_STATE_ALLOCATING;
dev->seq_number++;
bi->seq_number = dev->seq_number;
dev->n_erased_blocks--;
T(YAFFS_TRACE_ALLOCATE,
(TSTR("Allocated block %d, seq %d, %d left" TENDSTR),
dev->alloc_block_finder, dev->seq_number,
dev->n_erased_blocks));
return dev->alloc_block_finder;
}
}
T(YAFFS_TRACE_ALWAYS,
(TSTR
("yaffs tragedy: no more erased blocks, but there should have been %d"
TENDSTR), dev->n_erased_blocks));
return -1;
}
/*
* Check if there's space to allocate...
* Thinks.... do we need top make this ths same as yaffs_get_free_chunks()?
*/
int yaffs_check_alloc_available(yaffs_dev_t *dev, int n_chunks)
{
int reservedChunks;
int reservedBlocks = dev->param.n_reserved_blocks;
int checkpointBlocks;
checkpointBlocks = yaffs_calc_checkpt_blocks_required(dev);
reservedChunks = ((reservedBlocks + checkpointBlocks) * dev->param.chunks_per_block);
return (dev->n_free_chunks > (reservedChunks + n_chunks));
}
static int yaffs_alloc_chunk(yaffs_dev_t *dev, int useReserve,
yaffs_block_info_t **blockUsedPtr)
{
int retVal;
yaffs_block_info_t *bi;
if (dev->alloc_block < 0) {
/* Get next block to allocate off */
dev->alloc_block = yaffs_find_alloc_block(dev);
dev->alloc_page = 0;
}
if (!useReserve && !yaffs_check_alloc_available(dev, 1)) {
/* Not enough space to allocate unless we're allowed to use the reserve. */
return -1;
}
if (dev->n_erased_blocks < dev->param.n_reserved_blocks
&& dev->alloc_page == 0) {
T(YAFFS_TRACE_ALLOCATE, (TSTR("Allocating reserve" TENDSTR)));
}
/* Next page please.... */
if (dev->alloc_block >= 0) {
bi = yaffs_get_block_info(dev, dev->alloc_block);
retVal = (dev->alloc_block * dev->param.chunks_per_block) +
dev->alloc_page;
bi->pages_in_use++;
yaffs_set_chunk_bit(dev, dev->alloc_block,
dev->alloc_page);
dev->alloc_page++;
dev->n_free_chunks--;
/* If the block is full set the state to full */
if (dev->alloc_page >= dev->param.chunks_per_block) {
bi->block_state = YAFFS_BLOCK_STATE_FULL;
dev->alloc_block = -1;
}
if (blockUsedPtr)
*blockUsedPtr = bi;
return retVal;
}
T(YAFFS_TRACE_ERROR,
(TSTR("!!!!!!!!! Allocator out !!!!!!!!!!!!!!!!!" TENDSTR)));
return -1;
}
static int yaffs_get_erased_chunks(yaffs_dev_t *dev)
{
int n;
n = dev->n_erased_blocks * dev->param.chunks_per_block;
if (dev->alloc_block > 0)
n += (dev->param.chunks_per_block - dev->alloc_page);
return n;
}
/*
* yaffs_skip_rest_of_block() skips over the rest of the allocation block
* if we don't want to write to it.
*/
void yaffs_skip_rest_of_block(yaffs_dev_t *dev)
{
if(dev->alloc_block > 0){
yaffs_block_info_t *bi = yaffs_get_block_info(dev, dev->alloc_block);
if(bi->block_state == YAFFS_BLOCK_STATE_ALLOCATING){
bi->block_state = YAFFS_BLOCK_STATE_FULL;
dev->alloc_block = -1;
}
}
}
static int yaffs_gc_block(yaffs_dev_t *dev, int block,
int wholeBlock)
{
int oldChunk;
int newChunk;
int mark_flash;
int retVal = YAFFS_OK;
int i;
int isCheckpointBlock;
int matchingChunk;
int maxCopies;
int chunksBefore = yaffs_get_erased_chunks(dev);
int chunksAfter;
yaffs_ext_tags tags;
yaffs_block_info_t *bi = yaffs_get_block_info(dev, block);
yaffs_obj_t *object;
isCheckpointBlock = (bi->block_state == YAFFS_BLOCK_STATE_CHECKPOINT);
T(YAFFS_TRACE_TRACING,
(TSTR("Collecting block %d, in use %d, shrink %d, wholeBlock %d" TENDSTR),
block,
bi->pages_in_use,
bi->has_shrink_hdr,
wholeBlock));
/*yaffs_verify_free_chunks(dev); */
if(bi->block_state == YAFFS_BLOCK_STATE_FULL)
bi->block_state = YAFFS_BLOCK_STATE_COLLECTING;
bi->has_shrink_hdr = 0; /* clear the flag so that the block can erase */
dev->gc_disable = 1;
if (isCheckpointBlock ||
!yaffs_still_some_chunks(dev, block)) {
T(YAFFS_TRACE_TRACING,
(TSTR
("Collecting block %d that has no chunks in use" TENDSTR),
block));
yaffs_block_became_dirty(dev, block);
} else {
__u8 *buffer = yaffs_get_temp_buffer(dev, __LINE__);
yaffs_verify_blk(dev, bi, block);
maxCopies = (wholeBlock) ? dev->param.chunks_per_block : 5;
oldChunk = block * dev->param.chunks_per_block + dev->gc_chunk;
for (/* init already done */;
retVal == YAFFS_OK &&
dev->gc_chunk < dev->param.chunks_per_block &&
(bi->block_state == YAFFS_BLOCK_STATE_COLLECTING) &&
maxCopies > 0;
dev->gc_chunk++, oldChunk++) {
if (yaffs_check_chunk_bit(dev, block, dev->gc_chunk)) {
/* This page is in use and might need to be copied off */
maxCopies--;
mark_flash = 1;
yaffs_init_tags(&tags);
yaffs_rd_chunk_tags_nand(dev, oldChunk,
buffer, &tags);
object =
yaffs_find_by_number(dev,
tags.obj_id);
T(YAFFS_TRACE_GC_DETAIL,
(TSTR
("Collecting chunk in block %d, %d %d %d " TENDSTR),
dev->gc_chunk, tags.obj_id, tags.chunk_id,
tags.n_bytes));
if (object && !yaffs_skip_verification(dev)) {
if (tags.chunk_id == 0)
matchingChunk = object->hdr_chunk;
else if (object->soft_del)
matchingChunk = oldChunk; /* Defeat the test */
else
matchingChunk = yaffs_find_chunk_in_file(object, tags.chunk_id, NULL);
if (oldChunk != matchingChunk)
T(YAFFS_TRACE_ERROR,
(TSTR("gc: page in gc mismatch: %d %d %d %d"TENDSTR),
oldChunk, matchingChunk, tags.obj_id, tags.chunk_id));
}
if (!object) {
T(YAFFS_TRACE_ERROR,
(TSTR
("page %d in gc has no object: %d %d %d "
TENDSTR), oldChunk,
tags.obj_id, tags.chunk_id, tags.n_bytes));
}
if (object &&
object->deleted &&
object->soft_del &&
tags.chunk_id != 0) {
/* Data chunk in a soft deleted file, throw it away
* It's a soft deleted data chunk,
* No need to copy this, just forget about it and
* fix up the object.
*/
/* Free chunks already includes softdeleted chunks.
* How ever this chunk is going to soon be really deleted
* which will increment free chunks.
* We have to decrement free chunks so this works out properly.
*/
dev->n_free_chunks--;
bi->soft_del_pages--;
object->n_data_chunks--;
if (object->n_data_chunks <= 0) {
/* remeber to clean up the object */
dev->gc_cleanup_list[dev->n_clean_ups] =
tags.obj_id;
dev->n_clean_ups++;
}
mark_flash = 0;
} else if (0) {
/* Todo object && object->deleted && object->n_data_chunks == 0 */
/* Deleted object header with no data chunks.
* Can be discarded and the file deleted.
*/
object->hdr_chunk = 0;
yaffs_free_tnode(object->my_dev,
object->variant.
file_variant.top);
object->variant.file_variant.top = NULL;
yaffs_generic_obj_del(object);
} else if (object) {
/* It's either a data chunk in a live file or
* an ObjectHeader, so we're interested in it.
* NB Need to keep the ObjectHeaders of deleted files
* until the whole file has been deleted off
*/
tags.serial_number++;
dev->n_gc_copies++;
if (tags.chunk_id == 0) {
/* It is an object Id,
* We need to nuke the shrinkheader flags first
* Also need to clean up shadowing.
* We no longer want the shrinkHeader flag since its work is done
* and if it is left in place it will mess up scanning.
*/
yaffs_obj_header *oh;
oh = (yaffs_obj_header *)buffer;
oh->is_shrink = 0;
tags.extra_is_shrink = 0;
oh->shadows_obj = 0;
oh->inband_shadowed_obj_id = 0;
tags.extra_shadows = 0;
/* Update file size */
if(object->variant_type == YAFFS_OBJECT_TYPE_FILE){
oh->file_size = object->variant.file_variant.file_size;
tags.extra_length = oh->file_size;
}
yaffs_verify_oh(object, oh, &tags, 1);
newChunk =
yaffs_write_new_chunk(dev,(__u8 *) oh, &tags, 1);
} else
newChunk =
yaffs_write_new_chunk(dev, buffer, &tags, 1);
if (newChunk < 0) {
retVal = YAFFS_FAIL;
} else {
/* Ok, now fix up the Tnodes etc. */
if (tags.chunk_id == 0) {
/* It's a header */
object->hdr_chunk = newChunk;
object->serial = tags.serial_number;
} else {
/* It's a data chunk */
int ok;
ok = yaffs_put_chunk_in_file
(object,
tags.chunk_id,
newChunk, 0);
}
}
}
if (retVal == YAFFS_OK)
yaffs_chunk_del(dev, oldChunk, mark_flash, __LINE__);
}
}
yaffs_release_temp_buffer(dev, buffer, __LINE__);
}
yaffs_verify_collected_blk(dev, bi, block);
if (bi->block_state == YAFFS_BLOCK_STATE_COLLECTING) {
/*
* The gc did not complete. Set block state back to FULL
* because checkpointing does not restore gc.
*/
bi->block_state = YAFFS_BLOCK_STATE_FULL;
} else {
/* The gc completed. */
/* Do any required cleanups */
for (i = 0; i < dev->n_clean_ups; i++) {
/* Time to delete the file too */
object =
yaffs_find_by_number(dev,
dev->gc_cleanup_list[i]);
if (object) {
yaffs_free_tnode(dev,
object->variant.file_variant.
top);
object->variant.file_variant.top = NULL;
T(YAFFS_TRACE_GC,
(TSTR
("yaffs: About to finally delete object %d"
TENDSTR), object->obj_id));
yaffs_generic_obj_del(object);
object->my_dev->n_deleted_files--;
}
}
chunksAfter = yaffs_get_erased_chunks(dev);
if (chunksBefore >= chunksAfter) {
T(YAFFS_TRACE_GC,
(TSTR
("gc did not increase free chunks before %d after %d"
TENDSTR), chunksBefore, chunksAfter));
}
dev->gc_block = 0;
dev->gc_chunk = 0;
dev->n_clean_ups = 0;
}
dev->gc_disable = 0;
return retVal;
}
/*
* FindBlockForgarbageCollection is used to select the dirtiest block (or close enough)
* for garbage collection.
*/
static unsigned yaffs_find_gc_block(yaffs_dev_t *dev,
int aggressive,
int background)
{
int i;
int iterations;
unsigned selected = 0;
int prioritised = 0;
int prioritisedExists = 0;
yaffs_block_info_t *bi;
int threshold;
/* First let's see if we need to grab a prioritised block */
if (dev->has_pending_prioritised_gc && !aggressive) {
dev->gc_dirtiest = 0;
bi = dev->block_info;
for (i = dev->internal_start_block;
i <= dev->internal_end_block && !selected;
i++) {
if (bi->gc_prioritise) {
prioritisedExists = 1;
if (bi->block_state == YAFFS_BLOCK_STATE_FULL &&
yaffs_block_ok_for_gc(dev, bi)) {
selected = i;
prioritised = 1;
}
}
bi++;
}
/*
* If there is a prioritised block and none was selected then
* this happened because there is at least one old dirty block gumming
* up the works. Let's gc the oldest dirty block.
*/
if(prioritisedExists &&
!selected &&
dev->oldest_dirty_block > 0)
selected = dev->oldest_dirty_block;
if (!prioritisedExists) /* None found, so we can clear this */
dev->has_pending_prioritised_gc = 0;
}
/* If we're doing aggressive GC then we are happy to take a less-dirty block, and
* search harder.
* else (we're doing a leasurely gc), then we only bother to do this if the
* block has only a few pages in use.
*/
if (!selected){
int pagesUsed;
int nBlocks = dev->internal_end_block - dev->internal_start_block + 1;
if (aggressive){
threshold = dev->param.chunks_per_block;
iterations = nBlocks;
} else {
int maxThreshold;
if(background)
maxThreshold = dev->param.chunks_per_block/2;
else
maxThreshold = dev->param.chunks_per_block/8;
if(maxThreshold < YAFFS_GC_PASSIVE_THRESHOLD)
maxThreshold = YAFFS_GC_PASSIVE_THRESHOLD;
threshold = background ?
(dev->gc_not_done + 2) * 2 : 0;
if(threshold <YAFFS_GC_PASSIVE_THRESHOLD)
threshold = YAFFS_GC_PASSIVE_THRESHOLD;
if(threshold > maxThreshold)
threshold = maxThreshold;
iterations = nBlocks / 16 + 1;
if (iterations > 100)
iterations = 100;
}
for (i = 0;
i < iterations &&
(dev->gc_dirtiest < 1 ||
dev->gc_pages_in_use > YAFFS_GC_GOOD_ENOUGH);
i++) {
dev->gc_block_finder++;
if (dev->gc_block_finder < dev->internal_start_block ||
dev->gc_block_finder > dev->internal_end_block)
dev->gc_block_finder = dev->internal_start_block;
bi = yaffs_get_block_info(dev, dev->gc_block_finder);
pagesUsed = bi->pages_in_use - bi->soft_del_pages;
if (bi->block_state == YAFFS_BLOCK_STATE_FULL &&
pagesUsed < dev->param.chunks_per_block &&
(dev->gc_dirtiest < 1 || pagesUsed < dev->gc_pages_in_use) &&
yaffs_block_ok_for_gc(dev, bi)) {
dev->gc_dirtiest = dev->gc_block_finder;
dev->gc_pages_in_use = pagesUsed;
}
}
if(dev->gc_dirtiest > 0 && dev->gc_pages_in_use <= threshold)
selected = dev->gc_dirtiest;
}
/*
* If nothing has been selected for a while, try selecting the oldest dirty
* because that's gumming up the works.
*/
if(!selected && dev->param.is_yaffs2 &&
dev->gc_not_done >= ( background ? 10 : 20)){
yaffs2_find_oldest_dirty_seq(dev);
if(dev->oldest_dirty_block > 0) {
selected = dev->oldest_dirty_block;
dev->gc_dirtiest = selected;
dev->oldest_dirty_gc_count++;
bi = yaffs_get_block_info(dev, selected);
dev->gc_pages_in_use = bi->pages_in_use - bi->soft_del_pages;
} else
dev->gc_not_done = 0;
}
if(selected){
T(YAFFS_TRACE_GC,
(TSTR("GC Selected block %d with %d free, prioritised:%d" TENDSTR),
selected,
dev->param.chunks_per_block - dev->gc_pages_in_use,
prioritised));
dev->n_gc_blocks++;
if(background)
dev->bg_gcs++;
dev->gc_dirtiest = 0;
dev->gc_pages_in_use = 0;
dev->gc_not_done = 0;
if(dev->refresh_skip > 0)
dev->refresh_skip--;
} else{
dev->gc_not_done++;
T(YAFFS_TRACE_GC,
(TSTR("GC none: finder %d skip %d threshold %d dirtiest %d using %d oldest %d%s" TENDSTR),
dev->gc_block_finder, dev->gc_not_done,
threshold,
dev->gc_dirtiest, dev->gc_pages_in_use,
dev->oldest_dirty_block,
background ? " bg" : ""));
}
return selected;
}
/* New garbage collector
* If we're very low on erased blocks then we do aggressive garbage collection
* otherwise we do "leasurely" garbage collection.
* Aggressive gc looks further (whole array) and will accept less dirty blocks.
* Passive gc only inspects smaller areas and will only accept more dirty blocks.
*
* The idea is to help clear out space in a more spread-out manner.
* Dunno if it really does anything useful.
*/
static int yaffs_check_gc(yaffs_dev_t *dev, int background)
{
int aggressive = 0;
int gcOk = YAFFS_OK;
int maxTries = 0;
int minErased;
int erasedChunks;
int checkpointBlockAdjust;
if(dev->param.gc_control &&
(dev->param.gc_control(dev) & 1) == 0)
return YAFFS_OK;
if (dev->gc_disable) {
/* Bail out so we don't get recursive gc */
return YAFFS_OK;
}
/* This loop should pass the first time.
* We'll only see looping here if the collection does not increase space.
*/
do {
maxTries++;
checkpointBlockAdjust = yaffs_calc_checkpt_blocks_required(dev);
minErased = dev->param.n_reserved_blocks + checkpointBlockAdjust + 1;
erasedChunks = dev->n_erased_blocks * dev->param.chunks_per_block;
/* If we need a block soon then do aggressive gc.*/
if (dev->n_erased_blocks < minErased)
aggressive = 1;
else {
if(!background && erasedChunks > (dev->n_free_chunks / 4))
break;
if(dev->gc_skip > 20)
dev->gc_skip = 20;
if(erasedChunks < dev->n_free_chunks/2 ||
dev->gc_skip < 1 ||
background)
aggressive = 0;
else {
dev->gc_skip--;
break;
}
}
dev->gc_skip = 5;
/* If we don't already have a block being gc'd then see if we should start another */
if (dev->gc_block < 1 && !aggressive) {
dev->gc_block = yaffs2_find_refresh_block(dev);
dev->gc_chunk = 0;
dev->n_clean_ups=0;
}
if (dev->gc_block < 1) {
dev->gc_block = yaffs_find_gc_block(dev, aggressive, background);
dev->gc_chunk = 0;
dev->n_clean_ups=0;
}
if (dev->gc_block > 0) {
dev->all_gcs++;
if (!aggressive)
dev->passive_gc_count++;
T(YAFFS_TRACE_GC,
(TSTR
("yaffs: GC erasedBlocks %d aggressive %d" TENDSTR),
dev->n_erased_blocks, aggressive));
gcOk = yaffs_gc_block(dev, dev->gc_block, aggressive);
}
if (dev->n_erased_blocks < (dev->param.n_reserved_blocks) && dev->gc_block > 0) {
T(YAFFS_TRACE_GC,
(TSTR
("yaffs: GC !!!no reclaim!!! erasedBlocks %d after try %d block %d"
TENDSTR), dev->n_erased_blocks, maxTries, dev->gc_block));
}
} while ((dev->n_erased_blocks < dev->param.n_reserved_blocks) &&
(dev->gc_block > 0) &&
(maxTries < 2));
return aggressive ? gcOk : YAFFS_OK;
}
/*
* yaffs_bg_gc()
* Garbage collects. Intended to be called from a background thread.
* Returns non-zero if at least half the free chunks are erased.
*/
int yaffs_bg_gc(yaffs_dev_t *dev, unsigned urgency)
{
int erasedChunks = dev->n_erased_blocks * dev->param.chunks_per_block;
T(YAFFS_TRACE_BACKGROUND, (TSTR("Background gc %u" TENDSTR),urgency));
yaffs_check_gc(dev, 1);
return erasedChunks > dev->n_free_chunks/2;
}
/*------------------------- TAGS --------------------------------*/
static int yaffs_tags_match(const yaffs_ext_tags *tags, int obj_id,
int chunkInObject)
{
return (tags->chunk_id == chunkInObject &&
tags->obj_id == obj_id && !tags->is_deleted) ? 1 : 0;
}
/*-------------------- Data file manipulation -----------------*/
static int yaffs_find_chunk_in_file(yaffs_obj_t *in, int inode_chunk,
yaffs_ext_tags *tags)
{
/*Get the Tnode, then get the level 0 offset chunk offset */
yaffs_tnode_t *tn;
int theChunk = -1;
yaffs_ext_tags localTags;
int retVal = -1;
yaffs_dev_t *dev = in->my_dev;
if (!tags) {
/* Passed a NULL, so use our own tags space */
tags = &localTags;
}
tn = yaffs_find_tnode_0(dev, &in->variant.file_variant, inode_chunk);
if (tn) {
theChunk = yaffs_get_group_base(dev, tn, inode_chunk);
retVal =
yaffs_find_chunk_in_group(dev, theChunk, tags, in->obj_id,
inode_chunk);
}
return retVal;
}
static int yaffs_find_del_file_chunk(yaffs_obj_t *in, int inode_chunk,
yaffs_ext_tags *tags)
{
/* Get the Tnode, then get the level 0 offset chunk offset */
yaffs_tnode_t *tn;
int theChunk = -1;
yaffs_ext_tags localTags;
yaffs_dev_t *dev = in->my_dev;
int retVal = -1;
if (!tags) {
/* Passed a NULL, so use our own tags space */
tags = &localTags;
}
tn = yaffs_find_tnode_0(dev, &in->variant.file_variant, inode_chunk);
if (tn) {
theChunk = yaffs_get_group_base(dev, tn, inode_chunk);
retVal =
yaffs_find_chunk_in_group(dev, theChunk, tags, in->obj_id,
inode_chunk);
/* Delete the entry in the filestructure (if found) */
if (retVal != -1)
yaffs_load_tnode_0(dev, tn, inode_chunk, 0);
}
return retVal;
}
int yaffs_put_chunk_in_file(yaffs_obj_t *in, int inode_chunk,
int nand_chunk, int in_scan)
{
/* NB in_scan is zero unless scanning.
* For forward scanning, in_scan is > 0;
* for backward scanning in_scan is < 0
*
* nand_chunk = 0 is a dummy insert to make sure the tnodes are there.
*/
yaffs_tnode_t *tn;
yaffs_dev_t *dev = in->my_dev;
int existingChunk;
yaffs_ext_tags existingTags;
yaffs_ext_tags newTags;
unsigned existingSerial, newSerial;
if (in->variant_type != YAFFS_OBJECT_TYPE_FILE) {
/* Just ignore an attempt at putting a chunk into a non-file during scanning
* If it is not during Scanning then something went wrong!
*/
if (!in_scan) {
T(YAFFS_TRACE_ERROR,
(TSTR
("yaffs tragedy:attempt to put data chunk into a non-file"
TENDSTR)));
YBUG();
}
yaffs_chunk_del(dev, nand_chunk, 1, __LINE__);
return YAFFS_OK;
}
tn = yaffs_add_find_tnode_0(dev,
&in->variant.file_variant,
inode_chunk,
NULL);
if (!tn)
return YAFFS_FAIL;
if(!nand_chunk)
/* Dummy insert, bail now */
return YAFFS_OK;
existingChunk = yaffs_get_group_base(dev, tn, inode_chunk);
if (in_scan != 0) {
/* If we're scanning then we need to test for duplicates
* NB This does not need to be efficient since it should only ever
* happen when the power fails during a write, then only one
* chunk should ever be affected.
*
* Correction for YAFFS2: This could happen quite a lot and we need to think about efficiency! TODO
* Update: For backward scanning we don't need to re-read tags so this is quite cheap.
*/
if (existingChunk > 0) {
/* NB Right now existing chunk will not be real chunk_id if the chunk group size > 1
* thus we have to do a FindChunkInFile to get the real chunk id.
*
* We have a duplicate now we need to decide which one to use:
*
* Backwards scanning YAFFS2: The old one is what we use, dump the new one.
* Forward scanning YAFFS2: The new one is what we use, dump the old one.
* YAFFS1: Get both sets of tags and compare serial numbers.
*/
if (in_scan > 0) {
/* Only do this for forward scanning */
yaffs_rd_chunk_tags_nand(dev,
nand_chunk,
NULL, &newTags);
/* Do a proper find */
existingChunk =
yaffs_find_chunk_in_file(in, inode_chunk,
&existingTags);
}
if (existingChunk <= 0) {
/*Hoosterman - how did this happen? */
T(YAFFS_TRACE_ERROR,
(TSTR
("yaffs tragedy: existing chunk < 0 in scan"
TENDSTR)));
}
/* NB The deleted flags should be false, otherwise the chunks will
* not be loaded during a scan
*/
if (in_scan > 0) {
newSerial = newTags.serial_number;
existingSerial = existingTags.serial_number;
}
if ((in_scan > 0) &&
(existingChunk <= 0 ||
((existingSerial + 1) & 3) == newSerial)) {
/* Forward scanning.
* Use new
* Delete the old one and drop through to update the tnode
*/
yaffs_chunk_del(dev, existingChunk, 1,
__LINE__);
} else {
/* Backward scanning or we want to use the existing one
* Use existing.
* Delete the new one and return early so that the tnode isn't changed
*/
yaffs_chunk_del(dev, nand_chunk, 1,
__LINE__);
return YAFFS_OK;
}
}
}
if (existingChunk == 0)
in->n_data_chunks++;
yaffs_load_tnode_0(dev, tn, inode_chunk, nand_chunk);
return YAFFS_OK;
}
static int yaffs_rd_data_obj(yaffs_obj_t *in, int inode_chunk,
__u8 *buffer)
{
int nand_chunk = yaffs_find_chunk_in_file(in, inode_chunk, NULL);
if (nand_chunk >= 0)
return yaffs_rd_chunk_tags_nand(in->my_dev, nand_chunk,
buffer, NULL);
else {
T(YAFFS_TRACE_NANDACCESS,
(TSTR("Chunk %d not found zero instead" TENDSTR),
nand_chunk));
/* get sane (zero) data if you read a hole */
memset(buffer, 0, in->my_dev->data_bytes_per_chunk);
return 0;
}
}
void yaffs_chunk_del(yaffs_dev_t *dev, int chunk_id, int mark_flash, int lyn)
{
int block;
int page;
yaffs_ext_tags tags;
yaffs_block_info_t *bi;
if (chunk_id <= 0)
return;
dev->n_deletions++;
block = chunk_id / dev->param.chunks_per_block;
page = chunk_id % dev->param.chunks_per_block;
if (!yaffs_check_chunk_bit(dev, block, page))
T(YAFFS_TRACE_VERIFY,
(TSTR("Deleting invalid chunk %d"TENDSTR),
chunk_id));
bi = yaffs_get_block_info(dev, block);
yaffs2_update_oldest_dirty_seq(dev, block, bi);
T(YAFFS_TRACE_DELETION,
(TSTR("line %d delete of chunk %d" TENDSTR), lyn, chunk_id));
if (!dev->param.is_yaffs2 && mark_flash &&
bi->block_state != YAFFS_BLOCK_STATE_COLLECTING) {
yaffs_init_tags(&tags);
tags.is_deleted = 1;
yaffs_wr_chunk_tags_nand(dev, chunk_id, NULL, &tags);
yaffs_handle_chunk_update(dev, chunk_id, &tags);
} else {
dev->n_unmarked_deletions++;
}
/* Pull out of the management area.
* If the whole block became dirty, this will kick off an erasure.
*/
if (bi->block_state == YAFFS_BLOCK_STATE_ALLOCATING ||
bi->block_state == YAFFS_BLOCK_STATE_FULL ||
bi->block_state == YAFFS_BLOCK_STATE_NEEDS_SCANNING ||
bi->block_state == YAFFS_BLOCK_STATE_COLLECTING) {
dev->n_free_chunks++;
yaffs_clear_chunk_bit(dev, block, page);
bi->pages_in_use--;
if (bi->pages_in_use == 0 &&
!bi->has_shrink_hdr &&
bi->block_state != YAFFS_BLOCK_STATE_ALLOCATING &&
bi->block_state != YAFFS_BLOCK_STATE_NEEDS_SCANNING) {
yaffs_block_became_dirty(dev, block);
}
}
}
static int yaffs_wr_data_obj(yaffs_obj_t *in, int inode_chunk,
const __u8 *buffer, int n_bytes,
int useReserve)
{
/* Find old chunk Need to do this to get serial number
* Write new one and patch into tree.
* Invalidate old tags.
*/
int prevChunkId;
yaffs_ext_tags prevTags;
int newChunkId;
yaffs_ext_tags newTags;
yaffs_dev_t *dev = in->my_dev;
yaffs_check_gc(dev,0);
/* Get the previous chunk at this location in the file if it exists.
* If it does not exist then put a zero into the tree. This creates
* the tnode now, rather than later when it is harder to clean up.
*/
prevChunkId = yaffs_find_chunk_in_file(in, inode_chunk, &prevTags);
if(prevChunkId < 1 &&
!yaffs_put_chunk_in_file(in, inode_chunk, 0, 0))
return 0;
/* Set up new tags */
yaffs_init_tags(&newTags);
newTags.chunk_id = inode_chunk;
newTags.obj_id = in->obj_id;
newTags.serial_number =
(prevChunkId > 0) ? prevTags.serial_number + 1 : 1;
newTags.n_bytes = n_bytes;
if (n_bytes < 1 || n_bytes > dev->param.total_bytes_per_chunk) {
T(YAFFS_TRACE_ERROR,
(TSTR("Writing %d bytes to chunk!!!!!!!!!" TENDSTR), n_bytes));
YBUG();
}
newChunkId =
yaffs_write_new_chunk(dev, buffer, &newTags,
useReserve);
if (newChunkId > 0) {
yaffs_put_chunk_in_file(in, inode_chunk, newChunkId, 0);
if (prevChunkId > 0)
yaffs_chunk_del(dev, prevChunkId, 1, __LINE__);
yaffs_verify_file_sane(in);
}
return newChunkId;
}
/* UpdateObjectHeader updates the header on NAND for an object.
* If name is not NULL, then that new name is used.
*/
int yaffs_update_oh(yaffs_obj_t *in, const YCHAR *name, int force,
int is_shrink, int shadows, yaffs_xattr_mod *xmod)
{
yaffs_block_info_t *bi;
yaffs_dev_t *dev = in->my_dev;
int prevChunkId;
int retVal = 0;
int result = 0;
int newChunkId;
yaffs_ext_tags newTags;
yaffs_ext_tags oldTags;
const YCHAR *alias = NULL;
__u8 *buffer = NULL;
YCHAR old_name[YAFFS_MAX_NAME_LENGTH + 1];
yaffs_obj_header *oh = NULL;
yaffs_strcpy(old_name, _Y("silly old name"));
if (!in->fake ||
in == dev->root_dir || /* The root_dir should also be saved */
force || xmod) {
yaffs_check_gc(dev,0);
yaffs_check_obj_details_loaded(in);
buffer = yaffs_get_temp_buffer(in->my_dev, __LINE__);
oh = (yaffs_obj_header *) buffer;
prevChunkId = in->hdr_chunk;
if (prevChunkId > 0) {
result = yaffs_rd_chunk_tags_nand(dev, prevChunkId,
buffer, &oldTags);
yaffs_verify_oh(in, oh, &oldTags, 0);
memcpy(old_name, oh->name, sizeof(oh->name));
memset(buffer, 0xFF, sizeof(yaffs_obj_header));
} else
memset(buffer, 0xFF, dev->data_bytes_per_chunk);
oh->type = in->variant_type;
oh->yst_mode = in->yst_mode;
oh->shadows_obj = oh->inband_shadowed_obj_id = shadows;
#ifdef CONFIG_YAFFS_WINCE
oh->win_atime[0] = in->win_atime[0];
oh->win_ctime[0] = in->win_ctime[0];
oh->win_mtime[0] = in->win_mtime[0];
oh->win_atime[1] = in->win_atime[1];
oh->win_ctime[1] = in->win_ctime[1];
oh->win_mtime[1] = in->win_mtime[1];
#else
oh->yst_uid = in->yst_uid;
oh->yst_gid = in->yst_gid;
oh->yst_atime = in->yst_atime;
oh->yst_mtime = in->yst_mtime;
oh->yst_ctime = in->yst_ctime;
oh->yst_rdev = in->yst_rdev;
#endif
if (in->parent)
oh->parent_obj_id = in->parent->obj_id;
else
oh->parent_obj_id = 0;
if (name && *name) {
memset(oh->name, 0, sizeof(oh->name));
yaffs_load_oh_from_name(dev,oh->name,name);
} else if (prevChunkId > 0)
memcpy(oh->name, old_name, sizeof(oh->name));
else
memset(oh->name, 0, sizeof(oh->name));
oh->is_shrink = is_shrink;
switch (in->variant_type) {
case YAFFS_OBJECT_TYPE_UNKNOWN:
/* Should not happen */
break;
case YAFFS_OBJECT_TYPE_FILE:
oh->file_size =
(oh->parent_obj_id == YAFFS_OBJECTID_DELETED
|| oh->parent_obj_id ==
YAFFS_OBJECTID_UNLINKED) ? 0 : in->variant.
file_variant.file_size;
break;
case YAFFS_OBJECT_TYPE_HARDLINK:
oh->equiv_id =
in->variant.hardlink_variant.equiv_id;
break;
case YAFFS_OBJECT_TYPE_SPECIAL:
/* Do nothing */
break;
case YAFFS_OBJECT_TYPE_DIRECTORY:
/* Do nothing */
break;
case YAFFS_OBJECT_TYPE_SYMLINK:
alias = in->variant.symlink_variant.alias;
if(!alias)
alias = _Y("no alias");
yaffs_strncpy(oh->alias,
alias,
YAFFS_MAX_ALIAS_LENGTH);
oh->alias[YAFFS_MAX_ALIAS_LENGTH] = 0;
break;
}
/* process any xattrib modifications */
if(xmod)
yaffs_apply_xattrib_mod(in, (char *)buffer, xmod);
/* Tags */
yaffs_init_tags(&newTags);
in->serial++;
newTags.chunk_id = 0;
newTags.obj_id = in->obj_id;
newTags.serial_number = in->serial;
/* Add extra info for file header */
newTags.extra_available = 1;
newTags.extra_parent_id = oh->parent_obj_id;
newTags.extra_length = oh->file_size;
newTags.extra_is_shrink = oh->is_shrink;
newTags.extra_equiv_id = oh->equiv_id;
newTags.extra_shadows = (oh->shadows_obj > 0) ? 1 : 0;
newTags.extra_obj_type = in->variant_type;
yaffs_verify_oh(in, oh, &newTags, 1);
/* Create new chunk in NAND */
newChunkId =
yaffs_write_new_chunk(dev, buffer, &newTags,
(prevChunkId > 0) ? 1 : 0);
if (newChunkId >= 0) {
in->hdr_chunk = newChunkId;
if (prevChunkId > 0) {
yaffs_chunk_del(dev, prevChunkId, 1,
__LINE__);
}
if (!yaffs_obj_cache_dirty(in))
in->dirty = 0;
/* If this was a shrink, then mark the block that the chunk lives on */
if (is_shrink) {
bi = yaffs_get_block_info(in->my_dev,
newChunkId / in->my_dev->param.chunks_per_block);
bi->has_shrink_hdr = 1;
}
}
retVal = newChunkId;
}
if (buffer)
yaffs_release_temp_buffer(dev, buffer, __LINE__);
return retVal;
}
/*------------------------ Short Operations Cache ----------------------------------------
* In many situations where there is no high level buffering (eg WinCE) a lot of
* reads might be short sequential reads, and a lot of writes may be short
* sequential writes. eg. scanning/writing a jpeg file.
* In these cases, a short read/write cache can provide a huge perfomance benefit
* with dumb-as-a-rock code.
* In Linux, the page cache provides read buffering aand the short op cache provides write
* buffering.
*
* There are a limited number (~10) of cache chunks per device so that we don't
* need a very intelligent search.
*/
static int yaffs_obj_cache_dirty(yaffs_obj_t *obj)
{
yaffs_dev_t *dev = obj->my_dev;
int i;
yaffs_cache_t *cache;
int nCaches = obj->my_dev->param.n_caches;
for (i = 0; i < nCaches; i++) {
cache = &dev->cache[i];
if (cache->object == obj &&
cache->dirty)
return 1;
}
return 0;
}
static void yaffs_flush_file_cache(yaffs_obj_t *obj)
{
yaffs_dev_t *dev = obj->my_dev;
int lowest = -99; /* Stop compiler whining. */
int i;
yaffs_cache_t *cache;
int chunkWritten = 0;