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gmini-linux/fs/yaffs2/yaffs_guts.c

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/*
* YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
*
* Copyright (C) 2002-2011 Aleph One Ltd.
* for Toby Churchill Ltd and Brightstar Engineering
*
* Created by Charles Manning <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 "yaffs_guts.h"
#include "yaffs_getblockinfo.h"
#include "yaffs_tagscompat.h"
#include "yaffs_tagsmarshall.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"
#include "yaffs_attribs.h"
#include "yaffs_summary.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"
/* Forward declarations */
static int yaffs_wr_data_obj(struct yaffs_obj *in, int inode_chunk,
const u8 *buffer, int n_bytes, int use_reserve);
static void yaffs_fix_null_name(struct yaffs_obj *obj, YCHAR *name,
int buffer_size);
/* Function to calculate chunk and offset */
void yaffs_addr_to_chunk(struct yaffs_dev *dev, loff_t addr,
int *chunk_out, u32 *offset_out)
{
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 chunk_base;
chunk /= dev->chunk_div;
chunk_base = ((loff_t) chunk) * dev->data_bytes_per_chunk;
offset = (u32) (addr - chunk_base);
}
*chunk_out = chunk;
*offset_out = 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 inline u32 calc_shifts_ceiling(u32 x)
{
int extra_bits;
int shifts;
shifts = extra_bits = 0;
while (x > 1) {
if (x & 1)
extra_bits++;
x >>= 1;
shifts++;
}
if (extra_bits)
shifts++;
return shifts;
}
/* Function to return the number of shifts to get a 1 in bit 0
*/
static inline u32 calc_shifts(u32 x)
{
u32 shifts;
shifts = 0;
if (!x)
return 0;
while (!(x & 1)) {
x >>= 1;
shifts++;
}
return shifts;
}
/*
* Temporary buffer manipulations.
*/
static int yaffs_init_tmp_buffers(struct yaffs_dev *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].in_use = 0;
buf = kmalloc(dev->param.total_bytes_per_chunk, GFP_NOFS);
dev->temp_buffer[i].buffer = buf;
}
return buf ? YAFFS_OK : YAFFS_FAIL;
}
u8 *yaffs_get_temp_buffer(struct yaffs_dev * dev)
{
int i;
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].in_use == 0) {
dev->temp_buffer[i].in_use = 1;
return dev->temp_buffer[i].buffer;
}
}
yaffs_trace(YAFFS_TRACE_BUFFERS, "Out of temp buffers");
/*
* If we got here then we have to allocate an unmanaged one
* This is not good.
*/
dev->unmanaged_buffer_allocs++;
return kmalloc(dev->data_bytes_per_chunk, GFP_NOFS);
}
void yaffs_release_temp_buffer(struct yaffs_dev *dev, u8 *buffer)
{
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].in_use = 0;
return;
}
}
if (buffer) {
/* assume it is an unmanaged one. */
yaffs_trace(YAFFS_TRACE_BUFFERS,
"Releasing unmanaged temp buffer");
kfree(buffer);
dev->unmanaged_buffer_deallocs++;
}
}
/*
* Functions for robustisizing TODO
*
*/
static void yaffs_handle_chunk_wr_ok(struct yaffs_dev *dev, int nand_chunk,
const u8 *data,
const struct yaffs_ext_tags *tags)
{
(void) dev;
(void) nand_chunk;
(void) data;
(void) tags;
}
static void yaffs_handle_chunk_update(struct yaffs_dev *dev, int nand_chunk,
const struct yaffs_ext_tags *tags)
{
(void) dev;
(void) nand_chunk;
(void) tags;
}
void yaffs_handle_chunk_error(struct yaffs_dev *dev,
struct yaffs_block_info *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 */
yaffs_trace(YAFFS_TRACE_ALWAYS,
"yaffs: Block struck out");
}
}
}
static void yaffs_handle_chunk_wr_error(struct yaffs_dev *dev, int nand_chunk,
int erased_ok)
{
int flash_block = nand_chunk / dev->param.chunks_per_block;
struct yaffs_block_info *bi = yaffs_get_block_info(dev, flash_block);
yaffs_handle_chunk_error(dev, bi);
if (erased_ok) {
/* Was an actual write failure,
* so mark the block for retirement.*/
bi->needs_retiring = 1;
yaffs_trace(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,
"**>> Block %d needs retiring", flash_block);
}
/* Delete the chunk */
yaffs_chunk_del(dev, nand_chunk, 1, __LINE__);
yaffs_skip_rest_of_block(dev);
}
/*
* Verification code
*/
/*
* Simple hash function. Needs to have a reasonable spread
*/
static inline int yaffs_hash_fn(int n)
{
if (n < 0)
n = -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.
*/
struct yaffs_obj *yaffs_root(struct yaffs_dev *dev)
{
return dev->root_dir;
}
struct yaffs_obj *yaffs_lost_n_found(struct yaffs_dev *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 *dev, int nand_chunk)
{
int retval = YAFFS_OK;
u8 *data = yaffs_get_temp_buffer(dev);
struct 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) {
yaffs_trace(YAFFS_TRACE_NANDACCESS,
"Chunk %d not erased", nand_chunk);
retval = YAFFS_FAIL;
}
yaffs_release_temp_buffer(dev, data);
return retval;
}
static int yaffs_verify_chunk_written(struct yaffs_dev *dev,
int nand_chunk,
const u8 *data,
struct yaffs_ext_tags *tags)
{
int retval = YAFFS_OK;
struct yaffs_ext_tags temp_tags;
u8 *buffer = yaffs_get_temp_buffer(dev);
int result;
result = yaffs_rd_chunk_tags_nand(dev, nand_chunk, buffer, &temp_tags);
if (memcmp(buffer, data, dev->data_bytes_per_chunk) ||
temp_tags.obj_id != tags->obj_id ||
temp_tags.chunk_id != tags->chunk_id ||
temp_tags.n_bytes != tags->n_bytes)
retval = YAFFS_FAIL;
yaffs_release_temp_buffer(dev, buffer);
return retval;
}
int yaffs_check_alloc_available(struct yaffs_dev *dev, int n_chunks)
{
int reserved_chunks;
int reserved_blocks = dev->param.n_reserved_blocks;
int checkpt_blocks;
checkpt_blocks = yaffs_calc_checkpt_blocks_required(dev);
reserved_chunks =
(reserved_blocks + checkpt_blocks) * dev->param.chunks_per_block;
return (dev->n_free_chunks > (reserved_chunks + n_chunks));
}
static int yaffs_find_alloc_block(struct yaffs_dev *dev)
{
int i;
struct yaffs_block_info *bi;
if (dev->n_erased_blocks < 1) {
/* Hoosterman we've got a problem.
* Can't get space to gc
*/
yaffs_trace(YAFFS_TRACE_ERROR,
"yaffs tragedy: no more erased blocks");
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--;
yaffs_trace(YAFFS_TRACE_ALLOCATE,
"Allocated block %d, seq %d, %d left" ,
dev->alloc_block_finder, dev->seq_number,
dev->n_erased_blocks);
return dev->alloc_block_finder;
}
}
yaffs_trace(YAFFS_TRACE_ALWAYS,
"yaffs tragedy: no more erased blocks, but there should have been %d",
dev->n_erased_blocks);
return -1;
}
static int yaffs_alloc_chunk(struct yaffs_dev *dev, int use_reserver,
struct yaffs_block_info **block_ptr)
{
int ret_val;
struct yaffs_block_info *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 (!use_reserver && !yaffs_check_alloc_available(dev, 1)) {
/* No space unless we're allowed to use the reserve. */
return -1;
}
if (dev->n_erased_blocks < dev->param.n_reserved_blocks
&& dev->alloc_page == 0)
yaffs_trace(YAFFS_TRACE_ALLOCATE, "Allocating reserve");
/* Next page please.... */
if (dev->alloc_block >= 0) {
bi = yaffs_get_block_info(dev, dev->alloc_block);
ret_val = (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 (block_ptr)
*block_ptr = bi;
return ret_val;
}
yaffs_trace(YAFFS_TRACE_ERROR,
"!!!!!!!!! Allocator out !!!!!!!!!!!!!!!!!");
return -1;
}
static int yaffs_get_erased_chunks(struct yaffs_dev *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(struct yaffs_dev *dev)
{
struct yaffs_block_info *bi;
if (dev->alloc_block > 0) {
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_write_new_chunk(struct yaffs_dev *dev,
const u8 *data,
struct yaffs_ext_tags *tags, int use_reserver)
{
int attempts = 0;
int write_ok = 0;
int chunk;
yaffs2_checkpt_invalidate(dev);
do {
struct yaffs_block_info *bi = 0;
int erased_ok = 0;
chunk = yaffs_alloc_chunk(dev, use_reserver, &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) {
erased_ok = yaffs_check_chunk_erased(dev, chunk);
if (erased_ok != YAFFS_OK) {
yaffs_trace(YAFFS_TRACE_ERROR,
"**>> yaffs chunk %d was not erased",
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;
}
}
write_ok = yaffs_wr_chunk_tags_nand(dev, chunk, data, tags);
if (!bi->skip_erased_check)
write_ok =
yaffs_verify_chunk_written(dev, chunk, data, tags);
if (write_ok != YAFFS_OK) {
/* Clean up aborted write, skip to next block and
* try another chunk */
yaffs_handle_chunk_wr_error(dev, chunk, erased_ok);
continue;
}
bi->skip_erased_check = 1;
/* Copy the data into the robustification buffer */
yaffs_handle_chunk_wr_ok(dev, chunk, data, tags);
} while (write_ok != YAFFS_OK &&
(yaffs_wr_attempts <= 0 || attempts <= yaffs_wr_attempts));
if (!write_ok)
chunk = -1;
if (attempts > 1) {
yaffs_trace(YAFFS_TRACE_ERROR,
"**>> yaffs write required %d attempts",
attempts);
dev->n_retried_writes += (attempts - 1);
}
return chunk;
}
/*
* Block retiring for handling a broken block.
*/
static void yaffs_retire_block(struct yaffs_dev *dev, int flash_block)
{
struct yaffs_block_info *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) {
yaffs_trace(YAFFS_TRACE_ALWAYS,
"yaffs: Failed to mark bad and erase block %d",
flash_block);
} else {
struct yaffs_ext_tags tags;
int chunk_id =
flash_block * dev->param.chunks_per_block;
u8 *buffer = yaffs_get_temp_buffer(dev);
memset(buffer, 0xff, dev->data_bytes_per_chunk);
memset(&tags, 0, sizeof(tags));
tags.seq_number = YAFFS_SEQUENCE_BAD_BLOCK;
if (dev->tagger.write_chunk_tags_fn(dev, chunk_id -
dev->chunk_offset,
buffer,
&tags) != YAFFS_OK)
yaffs_trace(YAFFS_TRACE_ALWAYS,
"yaffs: Failed to write bad block marker to block %d",
flash_block);
yaffs_release_temp_buffer(dev, buffer);
}
}
bi->block_state = YAFFS_BLOCK_STATE_DEAD;
bi->gc_prioritise = 0;
bi->needs_retiring = 0;
dev->n_retired_blocks++;
}
/*---------------- Name handling functions ------------*/
static u16 yaffs_calc_name_sum(const YCHAR *name)
{
u16 sum = 0;
u16 i = 1;
if (!name)
return 0;
while ((*name) && i < (YAFFS_MAX_NAME_LENGTH / 2)) {
/* 0x1f mask is case insensitive */
sum += ((*name) & 0x1f) * i;
i++;
name++;
}
return sum;
}
void yaffs_set_obj_name(struct yaffs_obj *obj, const YCHAR * name)
{
memset(obj->short_name, 0, sizeof(obj->short_name));
if (name && !name[0]) {
yaffs_fix_null_name(obj, obj->short_name,
YAFFS_SHORT_NAME_LENGTH);
name = obj->short_name;
} else if (name &&
strnlen(name, YAFFS_SHORT_NAME_LENGTH + 1) <=
YAFFS_SHORT_NAME_LENGTH) {
strcpy(obj->short_name, name);
}
obj->sum = yaffs_calc_name_sum(name);
}
void yaffs_set_obj_name_from_oh(struct yaffs_obj *obj,
const struct yaffs_obj_hdr *oh)
{
#ifdef CONFIG_YAFFS_AUTO_UNICODE
YCHAR tmp_name[YAFFS_MAX_NAME_LENGTH + 1];
memset(tmp_name, 0, sizeof(tmp_name));
yaffs_load_name_from_oh(obj->my_dev, tmp_name, oh->name,
YAFFS_MAX_NAME_LENGTH + 1);
yaffs_set_obj_name(obj, tmp_name);
#else
yaffs_set_obj_name(obj, oh->name);
#endif
}
loff_t yaffs_max_file_size(struct yaffs_dev *dev)
{
if(sizeof(loff_t) < 8)
return YAFFS_MAX_FILE_SIZE_32;
else
return ((loff_t) YAFFS_MAX_CHUNK_ID) * dev->data_bytes_per_chunk;
}
/*-------------------- TNODES -------------------
* List of spare tnodes
* The list is hooked together using the first pointer
* in the tnode.
*/
struct yaffs_tnode *yaffs_get_tnode(struct yaffs_dev *dev)
{
struct yaffs_tnode *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(struct yaffs_dev *dev, struct yaffs_tnode *tn)
{
yaffs_free_raw_tnode(dev, tn);
dev->n_tnodes--;
dev->checkpoint_blocks_required = 0; /* force recalculation */
}
static void yaffs_deinit_tnodes_and_objs(struct yaffs_dev *dev)
{
yaffs_deinit_raw_tnodes_and_objs(dev);
dev->n_obj = 0;
dev->n_tnodes = 0;
}
static void yaffs_load_tnode_0(struct yaffs_dev *dev, struct yaffs_tnode *tn,
unsigned pos, unsigned val)
{
u32 *map = (u32 *) tn;
u32 bit_in_map;
u32 bit_in_word;
u32 word_in_map;
u32 mask;
pos &= YAFFS_TNODES_LEVEL0_MASK;
val >>= dev->chunk_grp_bits;
bit_in_map = pos * dev->tnode_width;
word_in_map = bit_in_map / 32;
bit_in_word = bit_in_map & (32 - 1);
mask = dev->tnode_mask << bit_in_word;
map[word_in_map] &= ~mask;
map[word_in_map] |= (mask & (val << bit_in_word));
if (dev->tnode_width > (32 - bit_in_word)) {
bit_in_word = (32 - bit_in_word);
word_in_map++;
mask =
dev->tnode_mask >> bit_in_word;
map[word_in_map] &= ~mask;
map[word_in_map] |= (mask & (val >> bit_in_word));
}
}
u32 yaffs_get_group_base(struct yaffs_dev *dev, struct yaffs_tnode *tn,
unsigned pos)
{
u32 *map = (u32 *) tn;
u32 bit_in_map;
u32 bit_in_word;
u32 word_in_map;
u32 val;
pos &= YAFFS_TNODES_LEVEL0_MASK;
bit_in_map = pos * dev->tnode_width;
word_in_map = bit_in_map / 32;
bit_in_word = bit_in_map & (32 - 1);
val = map[word_in_map] >> bit_in_word;
if (dev->tnode_width > (32 - bit_in_word)) {
bit_in_word = (32 - bit_in_word);
word_in_map++;
val |= (map[word_in_map] << bit_in_word);
}
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. */
struct yaffs_tnode *yaffs_find_tnode_0(struct yaffs_dev *dev,
struct yaffs_file_var *file_struct,
u32 chunk_id)
{
struct yaffs_tnode *tn = file_struct->top;
u32 i;
int required_depth;
int level = file_struct->top_level;
(void) 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;
required_depth = 0;
while (i) {
i >>= YAFFS_TNODES_INTERNAL_BITS;
required_depth++;
}
if (required_depth > 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;
}
/* add_find_tnode_0 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.
*/
struct yaffs_tnode *yaffs_add_find_tnode_0(struct yaffs_dev *dev,
struct yaffs_file_var *file_struct,
u32 chunk_id,
struct yaffs_tnode *passed_tn)
{
int required_depth;
int i;
int l;
struct yaffs_tnode *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;
required_depth = 0;
while (x) {
x >>= YAFFS_TNODES_INTERNAL_BITS;
required_depth++;
}
if (required_depth > file_struct->top_level) {
/* Not tall enough, gotta make the tree taller */
for (i = file_struct->top_level; i < required_depth; i++) {
tn = yaffs_get_tnode(dev);
if (tn) {
tn->internal[0] = file_struct->top;
file_struct->top = tn;
file_struct->top_level++;
} else {
yaffs_trace(YAFFS_TRACE_ERROR,
"yaffs: no more tnodes");
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, 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_tags_match(const struct yaffs_ext_tags *tags, int obj_id,
int chunk_obj)
{
return (tags->chunk_id == chunk_obj &&
tags->obj_id == obj_id &&
!tags->is_deleted) ? 1 : 0;
}
static int yaffs_find_chunk_in_group(struct yaffs_dev *dev, int the_chunk,
struct yaffs_ext_tags *tags, int obj_id,
int inode_chunk)
{
int j;
for (j = 0; the_chunk && j < dev->chunk_grp_size; j++) {
if (yaffs_check_chunk_bit
(dev, the_chunk / dev->param.chunks_per_block,
the_chunk % dev->param.chunks_per_block)) {
if (dev->chunk_grp_size == 1)
return the_chunk;
else {
yaffs_rd_chunk_tags_nand(dev, the_chunk, NULL,
tags);
if (yaffs_tags_match(tags,
obj_id, inode_chunk)) {
/* found it; */
return the_chunk;
}
}
}
the_chunk++;
}
return -1;
}
static int yaffs_find_chunk_in_file(struct yaffs_obj *in, int inode_chunk,
struct yaffs_ext_tags *tags)
{
/*Get the Tnode, then get the level 0 offset chunk offset */
struct yaffs_tnode *tn;
int the_chunk = -1;
struct yaffs_ext_tags local_tags;
int ret_val = -1;
struct yaffs_dev *dev = in->my_dev;
if (!tags) {
/* Passed a NULL, so use our own tags space */
tags = &local_tags;
}
tn = yaffs_find_tnode_0(dev, &in->variant.file_variant, inode_chunk);
if (!tn)
return ret_val;
the_chunk = yaffs_get_group_base(dev, tn, inode_chunk);
ret_val = yaffs_find_chunk_in_group(dev, the_chunk, tags, in->obj_id,
inode_chunk);
return ret_val;
}
static int yaffs_find_del_file_chunk(struct yaffs_obj *in, int inode_chunk,
struct yaffs_ext_tags *tags)
{
/* Get the Tnode, then get the level 0 offset chunk offset */
struct yaffs_tnode *tn;
int the_chunk = -1;
struct yaffs_ext_tags local_tags;
struct yaffs_dev *dev = in->my_dev;
int ret_val = -1;
if (!tags) {
/* Passed a NULL, so use our own tags space */
tags = &local_tags;
}
tn = yaffs_find_tnode_0(dev, &in->variant.file_variant, inode_chunk);
if (!tn)
return ret_val;
the_chunk = yaffs_get_group_base(dev, tn, inode_chunk);
ret_val = yaffs_find_chunk_in_group(dev, the_chunk, tags, in->obj_id,
inode_chunk);
/* Delete the entry in the filestructure (if found) */
if (ret_val != -1)
yaffs_load_tnode_0(dev, tn, inode_chunk, 0);
return ret_val;
}
int yaffs_put_chunk_in_file(struct yaffs_obj *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.
*/
struct yaffs_tnode *tn;
struct yaffs_dev *dev = in->my_dev;
int existing_cunk;
struct yaffs_ext_tags existing_tags;
struct yaffs_ext_tags new_tags;
unsigned existing_serial, new_serial;
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) {
yaffs_trace(YAFFS_TRACE_ERROR,
"yaffs tragedy:attempt to put data chunk into a non-file"
);
BUG();
}
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;
existing_cunk = 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
* 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 (existing_cunk > 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.
* 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, &new_tags);
/* Do a proper find */
existing_cunk =
yaffs_find_chunk_in_file(in, inode_chunk,
&existing_tags);
}
if (existing_cunk <= 0) {
/*Hoosterman - how did this happen? */
yaffs_trace(YAFFS_TRACE_ERROR,
"yaffs tragedy: existing chunk < 0 in scan"
);
}
/* NB The deleted flags should be false, otherwise
* the chunks will not be loaded during a scan
*/
if (in_scan > 0) {
new_serial = new_tags.serial_number;
existing_serial = existing_tags.serial_number;
}
if ((in_scan > 0) &&
(existing_cunk <= 0 ||
((existing_serial + 1) & 3) == new_serial)) {
/* Forward scanning.
* Use new
* Delete the old one and drop through to
* update the tnode
*/
yaffs_chunk_del(dev, existing_cunk, 1,
__LINE__);
} else {
/* Backward scanning or we want to use the
* existing one
* 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 (existing_cunk == 0)
in->n_data_chunks++;
yaffs_load_tnode_0(dev, tn, inode_chunk, nand_chunk);
return YAFFS_OK;
}
static void yaffs_soft_del_chunk(struct yaffs_dev *dev, int chunk)
{
struct yaffs_block_info *the_block;
unsigned block_no;
yaffs_trace(YAFFS_TRACE_DELETION, "soft delete chunk %d", chunk);
block_no = chunk / dev->param.chunks_per_block;
the_block = yaffs_get_block_info(dev, block_no);
if (the_block) {
the_block->soft_del_pages++;
dev->n_free_chunks++;
yaffs2_update_oldest_dirty_seq(dev, block_no, the_block);
}
}
/* 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(struct yaffs_obj *in, struct yaffs_tnode *tn,
u32 level, int chunk_offset)
{
int i;
int the_chunk;
int all_done = 1;
struct yaffs_dev *dev = in->my_dev;
if (!tn)
return 1;
if (level > 0) {
for (i = YAFFS_NTNODES_INTERNAL - 1;
all_done && i >= 0;
i--) {
if (tn->internal[i]) {
all_done =
yaffs_soft_del_worker(in,
tn->internal[i],
level - 1,
(chunk_offset <<
YAFFS_TNODES_INTERNAL_BITS)
+ i);
if (all_done) {
yaffs_free_tnode(dev,
tn->internal[i]);
tn->internal[i] = NULL;
} else {
/* Can this happen? */
}
}
}
return (all_done) ? 1 : 0;
}
/* level 0 */
for (i = YAFFS_NTNODES_LEVEL0 - 1; i >= 0; i--) {
the_chunk = yaffs_get_group_base(dev, tn, i);
if (the_chunk) {
yaffs_soft_del_chunk(dev, the_chunk);
yaffs_load_tnode_0(dev, tn, i, 0);
}
}
return 1;
}
static void yaffs_remove_obj_from_dir(struct yaffs_obj *obj)
{
struct yaffs_dev *dev = obj->my_dev;
struct yaffs_obj *parent;
yaffs_verify_obj_in_dir(obj);
parent = obj->parent;
yaffs_verify_dir(parent);
if (dev && dev->param.remove_obj_fn)
dev->param.remove_obj_fn(obj);
list_del_init(&obj->siblings);
obj->parent = NULL;
yaffs_verify_dir(parent);
}
void yaffs_add_obj_to_dir(struct yaffs_obj *directory, struct yaffs_obj *obj)
{
if (!directory) {
yaffs_trace(YAFFS_TRACE_ALWAYS,
"tragedy: Trying to add an object to a null pointer directory"
);
BUG();
return;
}
if (directory->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY) {
yaffs_trace(YAFFS_TRACE_ALWAYS,
"tragedy: Trying to add an object to a non-directory"
);
BUG();
}
if (obj->siblings.prev == NULL) {
/* Not initialised */
BUG();
}
yaffs_verify_dir(directory);
yaffs_remove_obj_from_dir(obj);
/* Now add it */
list_add(&obj->siblings, &directory->variant.dir_variant.children);
obj->parent = directory;
if (directory == obj->my_dev->unlinked_dir
|| directory == obj->my_dev->del_dir) {
obj->unlinked = 1;
obj->my_dev->n_unlinked_files++;
obj->rename_allowed = 0;
}
yaffs_verify_dir(directory);
yaffs_verify_obj_in_dir(obj);
}
static int yaffs_change_obj_name(struct yaffs_obj *obj,
struct yaffs_obj *new_dir,
const YCHAR *new_name, int force, int shadows)
{
int unlink_op;
int del_op;
struct yaffs_obj *existing_target;
if (new_dir == NULL)
new_dir = obj->parent; /* use the old directory */
if (new_dir->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY) {
yaffs_trace(YAFFS_TRACE_ALWAYS,
"tragedy: yaffs_change_obj_name: new_dir is not a directory"
);
BUG();
}
unlink_op = (new_dir == obj->my_dev->unlinked_dir);
del_op = (new_dir == obj->my_dev->del_dir);
existing_target = 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 OK.
* else only proceed if the new name does not exist and we're putting
* it into a directory.
*/
if (!(unlink_op || del_op || force ||
shadows > 0 || !existing_target) ||
new_dir->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY)
return YAFFS_FAIL;
yaffs_set_obj_name(obj, new_name);
obj->dirty = 1;
yaffs_add_obj_to_dir(new_dir, obj);
if (unlink_op)
obj->unlinked = 1;
/* If it is a deletion then we mark it as a shrink for gc */
if (yaffs_update_oh(obj, new_name, 0, del_op, shadows, NULL) >= 0)
return YAFFS_OK;
return YAFFS_FAIL;
}
/*------------------------ Short Operations Cache ------------------------------
* In many situations where there is no high level buffering 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 and the short op cache
* provides write buffering.
*
* There are a small number (~10) of cache chunks per device so that we don't
* need a very intelligent search.
*/
static int yaffs_obj_cache_dirty(struct yaffs_obj *obj)
{
struct yaffs_dev *dev = obj->my_dev;
int i;
struct yaffs_cache *cache;
int n_caches = obj->my_dev->param.n_caches;
for (i = 0; i < n_caches; i++) {
cache = &dev->cache[i];
if (cache->object == obj && cache->dirty)
return 1;
}
return 0;
}
static void yaffs_flush_file_cache(struct yaffs_obj *obj)
{
struct yaffs_dev *dev = obj->my_dev;
int lowest = -99; /* Stop compiler whining. */
int i;
struct yaffs_cache *cache;
int chunk_written = 0;
int n_caches = obj->my_dev->param.n_caches;
if (n_caches < 1)
return;
do {
cache = NULL;
/* Find the lowest dirty chunk for this object */
for (i = 0; i < n_caches; i++) {
if (dev->cache[i].object == obj &&
dev->cache[i].dirty) {
if (!cache ||
dev->cache[i].chunk_id < lowest) {
cache = &dev->cache[i];
lowest = cache->chunk_id;
}
}
}
if (cache && !cache->locked) {
/* Write it out and free it up */
chunk_written =
yaffs_wr_data_obj(cache->object,
cache->chunk_id,
cache->data,
cache->n_bytes, 1);
cache->dirty = 0;
cache->object = NULL;
}
} while (cache && chunk_written > 0);
if (cache)
/* Hoosterman, disk full while writing cache out. */
yaffs_trace(YAFFS_TRACE_ERROR,
"yaffs tragedy: no space during cache write");
}
/*yaffs_flush_whole_cache(dev)
*
*
*/
void yaffs_flush_whole_cache(struct yaffs_dev *dev)
{
struct yaffs_obj *obj;
int n_caches = dev->param.n_caches;
int i;
/* Find a dirty object in the cache and flush it...
* until there are no further dirty objects.
*/
do {
obj = NULL;
for (i = 0; i < n_caches && !obj; i++) {
if (dev->cache[i].object && dev->cache[i].dirty)
obj = dev->cache[i].object;
}
if (obj)
yaffs_flush_file_cache(obj);
} while (obj);
}
/* Grab us a cache chunk for use.
* First look for an empty one.
* Then look for the least recently used non-dirty one.
* Then look for the least recently used dirty one...., flush and look again.
*/
static struct yaffs_cache *yaffs_grab_chunk_worker(struct yaffs_dev *dev)
{
int i;
if (dev->param.n_caches > 0) {
for (i = 0; i < dev->param.n_caches; i++) {
if (!dev->cache[i].object)
return &dev->cache[i];
}
}
return NULL;
}
static struct yaffs_cache *yaffs_grab_chunk_cache(struct yaffs_dev *dev)
{
struct yaffs_cache *cache;
struct yaffs_obj *the_obj;
int usage;
int i;
int pushout;
if (dev->param.n_caches < 1)
return NULL;
/* Try find a non-dirty one... */
cache = yaffs_grab_chunk_worker(dev);
if (!cache) {
/* They were all dirty, find the LRU object and flush
* its cache, then find again.
* NB what's here is not very accurate,
* we actually flush the object with the LRU chunk.
*/
/* With locking we can't assume we can use entry zero,
* Set the_obj to a valid pointer for Coverity. */
the_obj = dev->cache[0].object;
usage = -1;
cache = NULL;
pushout = -1;
for (i = 0; i < dev->param.n_caches; i++) {
if (dev->cache[i].object &&
!dev->cache[i].locked &&
(dev->cache[i].last_use < usage ||
!cache)) {
usage = dev->cache[i].last_use;
the_obj = dev->cache[i].object;
cache = &dev->cache[i];
pushout = i;
}
}
if (!cache || cache->dirty) {
/* Flush and try again */
yaffs_flush_file_cache(the_obj);
cache = yaffs_grab_chunk_worker(dev);
}
}
return cache;
}
/* Find a cached chunk */
static struct yaffs_cache *yaffs_find_chunk_cache(const struct yaffs_obj *obj,
int chunk_id)
{
struct yaffs_dev *dev = obj->my_dev;
int i;
if (dev->param.n_caches < 1)
return NULL;
for (i = 0; i < dev->param.n_caches; i++) {
if (dev->cache[i].object == obj &&
dev->cache[i].chunk_id == chunk_id) {
dev->cache_hits++;
return &dev->cache[i];
}
}
return NULL;
}
/* Mark the chunk for the least recently used algorithym */
static void yaffs_use_cache(struct yaffs_dev *dev, struct yaffs_cache *cache,
int is_write)
{
int i;
if (dev->param.n_caches < 1)
return;
if (dev->cache_last_use < 0 ||
dev->cache_last_use > 100000000) {
/* Reset the cache usages */
for (i = 1; i < dev->param.n_caches; i++)
dev->cache[i].last_use = 0;
dev->cache_last_use = 0;
}
dev->cache_last_use++;
cache->last_use = dev->cache_last_use;
if (is_write)
cache->dirty = 1;
}
/* Invalidate a single cache page.
* Do this when a whole page gets written,
* ie the short cache for this page is no longer valid.
*/
static void yaffs_invalidate_chunk_cache(struct yaffs_obj *object, int chunk_id)
{
struct yaffs_cache *cache;
if (object->my_dev->param.n_caches > 0) {
cache = yaffs_find_chunk_cache(object, chunk_id);
if (cache)
cache->object = NULL;
}
}
/* Invalidate all the cache pages associated with this object
* Do this whenever ther file is deleted or resized.
*/
static void yaffs_invalidate_whole_cache(struct yaffs_obj *in)
{
int i;
struct yaffs_dev *dev = in->my_dev;
if (dev->param.n_caches > 0) {
/* Invalidate it. */
for (i = 0; i < dev->param.n_caches; i++) {
if (dev->cache[i].object == in)
dev->cache[i].object = NULL;
}
}
}
static void yaffs_unhash_obj(struct yaffs_obj *obj)
{
int bucket;
struct yaffs_dev *dev = obj->my_dev;
/* If it is still linked into the bucket list, free from the list */
if (!list_empty(&obj->hash_link)) {
list_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(struct yaffs_obj *obj)
{
struct yaffs_dev *dev;
if (!obj) {
BUG();
return;
}
dev = obj->my_dev;
yaffs_trace(YAFFS_TRACE_OS, "FreeObject %p inode %p",
obj, obj->my_inode);
if (obj->parent)
BUG();
if (!list_empty(&obj->siblings))
BUG();
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(struct yaffs_obj *obj)
{
if (obj->defered_free)
yaffs_free_obj(obj);
}
static int yaffs_generic_obj_del(struct yaffs_obj *in)
{
/* Iinvalidate the file's data in the cache, without flushing. */
yaffs_invalidate_whole_cache(in);
if (in->my_dev->param.is_yaffs2 && in->parent != in->my_dev->del_dir) {
/* Move to unlinked directory so we have a deletion record */
yaffs_change_obj_name(in, in->my_dev->del_dir, _Y("deleted"), 0,
0);
}
yaffs_remove_obj_from_dir(in);
yaffs_chunk_del(in->my_dev, in->hdr_chunk, 1, __LINE__);
in->hdr_chunk = 0;
yaffs_free_obj(in);
return YAFFS_OK;
}
static void yaffs_soft_del_file(struct yaffs_obj *obj)
{
if (!obj->deleted ||
obj->variant_type != YAFFS_OBJECT_TYPE_FILE ||
obj->soft_del)
return;
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;
yaffs_trace(YAFFS_TRACE_TRACING,
"yaffs: Deleting empty file %d",
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 struct yaffs_tnode *yaffs_prune_worker(struct yaffs_dev *dev,
struct yaffs_tnode *tn, u32 level,
int del0)
{
int i;
int has_data;
if (!tn)
return tn;
has_data = 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])
has_data++;
}
} else {
int tnode_size_u32 = dev->tnode_size / sizeof(u32);
u32 *map = (u32 *) tn;
for (i = 0; !has_data && i < tnode_size_u32; i++) {
if (map[i])
has_data++;
}
}
if (has_data == 0 && del0) {
/* Free and return NULL */
yaffs_free_tnode(dev, tn);
tn = NULL;
}
return tn;
}
static int yaffs_prune_tree(struct yaffs_dev *dev,
struct yaffs_file_var *file_struct)
{
int i;
int has_data;
int done = 0;
struct yaffs_tnode *tn;
if (file_struct->top_level < 1)
return YAFFS_OK;
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;
has_data = 0;
for (i = 1; i < YAFFS_NTNODES_INTERNAL; i++) {
if (tn->internal[i])
has_data++;
}
if (!has_data) {
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.-------------------*/
/* alloc_empty_obj gets us a clean Object.*/
static struct yaffs_obj *yaffs_alloc_empty_obj(struct yaffs_dev *dev)
{
struct yaffs_obj *obj = yaffs_alloc_raw_obj(dev);
if (!obj)
return obj;
dev->n_obj++;
/* Now sweeten it up... */
memset(obj, 0, sizeof(struct yaffs_obj));
obj->being_created = 1;
obj->my_dev = dev;
obj->hdr_chunk = 0;
obj->variant_type = YAFFS_OBJECT_TYPE_UNKNOWN;
INIT_LIST_HEAD(&(obj->hard_links));
INIT_LIST_HEAD(&(obj->hash_link));
INIT_LIST_HEAD(&obj->siblings);
/* Now make the directory sane */
if (dev->root_dir) {
obj->parent = dev->root_dir;
list_add(&(obj->siblings),
&dev->root_dir->variant.dir_variant.children);
}
/* Add it to the lost and found directory.
* NB Can't put root or lost-n-found in lost-n-found so
* check if lost-n-found 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 int yaffs_find_nice_bucket(struct yaffs_dev *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(struct yaffs_dev *dev)
{
int bucket = yaffs_find_nice_bucket(dev);
int found = 0;
struct list_head *i;
u32 n = (u32) bucket;
/* Now find an object value that has not already been taken
* by scanning the list.
*/
while (!found) {
found = 1;
n += YAFFS_NOBJECT_BUCKETS;
if (1 || dev->obj_bucket[bucket].count > 0) {
list_for_each(i, &dev->obj_bucket[bucket].list) {
/* If there is already one in the list */
if (i && list_entry(i, struct yaffs_obj,
hash_link)->obj_id == n) {
found = 0;
}
}
}
}
return n;
}
static void yaffs_hash_obj(struct yaffs_obj *in)
{
int bucket = yaffs_hash_fn(in->obj_id);
struct yaffs_dev *dev = in->my_dev;
list_add(&in->hash_link, &dev->obj_bucket[bucket].list);
dev->obj_bucket[bucket].count++;
}
struct yaffs_obj *yaffs_find_by_number(struct yaffs_dev *dev, u32 number)
{
int bucket = yaffs_hash_fn(number);
struct list_head *i;
struct yaffs_obj *in;
list_for_each(i, &dev->obj_bucket[bucket].list) {
/* Look if it is in the list */
in = list_entry(i, struct yaffs_obj, hash_link);
if (in->obj_id == number) {
/* Don't show if it is defered free */
if (in->defered_free)
return NULL;
return in;
}
}
return NULL;
}
static struct yaffs_obj *yaffs_new_obj(struct yaffs_dev *dev, int number,
enum yaffs_obj_type type)
{
struct yaffs_obj *the_obj = NULL;
struct yaffs_tnode *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;
}
the_obj = yaffs_alloc_empty_obj(dev);
if (!the_obj) {
if (tn)
yaffs_free_tnode(dev, tn);
return NULL;
}
the_obj->fake = 0;
the_obj->rename_allowed = 1;
the_obj->unlink_allowed = 1;
the_obj->obj_id = number;
yaffs_hash_obj(the_obj);
the_obj->variant_type = type;
yaffs_load_current_time(the_obj, 1, 1);
switch (type) {
case YAFFS_OBJECT_TYPE_FILE:
the_obj->variant.file_variant.file_size = 0;
the_obj->variant.file_variant.scanned_size = 0;
the_obj->variant.file_variant.shrink_size =
yaffs_max_file_size(dev);
the_obj->variant.file_variant.top_level = 0;
the_obj->variant.file_variant.top = tn;
break;
case YAFFS_OBJECT_TYPE_DIRECTORY:
INIT_LIST_HEAD(&the_obj->variant.dir_variant.children);
INIT_LIST_HEAD(&the_obj->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 the_obj;
}
static struct yaffs_obj *yaffs_create_fake_dir(struct yaffs_dev *dev,
int number, u32 mode)
{
struct yaffs_obj *obj =
yaffs_new_obj(dev, number, YAFFS_OBJECT_TYPE_DIRECTORY);
if (!obj)
return NULL;
obj->fake = 1; /* it is fake so it might not use NAND */
obj->rename_allowed = 0;
obj->unlink_allowed = 0;
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_init_tnodes_and_objs(struct yaffs_dev *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++) {
INIT_LIST_HEAD(&dev->obj_bucket[i].list);
dev->obj_bucket[i].count = 0;
}
}
struct yaffs_obj *yaffs_find_or_create_by_number(struct yaffs_dev *dev,
int number,
enum yaffs_obj_type type)
{
struct yaffs_obj *the_obj = NULL;
if (number > 0)
the_obj = yaffs_find_by_number(dev, number);
if (!the_obj)
the_obj = yaffs_new_obj(dev, number, type);
return the_obj;
}
YCHAR *yaffs_clone_str(const YCHAR *str)
{
YCHAR *new_str = NULL;
int len;
if (!str)
str = _Y("");
len = strnlen(str, YAFFS_MAX_ALIAS_LENGTH);
new_str = kmalloc((len + 1) * sizeof(YCHAR), GFP_NOFS);
if (new_str) {
strncpy(new_str, str, len);
new_str[len] = 0;
}
return new_str;
}
/*
*yaffs_update_parent() handles fixing a directories mtime and ctime when a new
* link (ie. name) is created or deleted in the directory.
*
* ie.
* create dir/a : update dir's mtime/ctime
* rm dir/a: update dir's mtime/ctime
* modify dir/a: don't update dir's mtimme/ctime
*
* This can be handled immediately or defered. Defering helps reduce the number
* of updates when many files in a directory are changed within a brief period.
*
* If the directory updating is defered then yaffs_update_dirty_dirs must be
* called periodically.
*/
static void yaffs_update_parent(struct yaffs_obj *obj)
{
struct yaffs_dev *dev;
if (!obj)
return;
dev = obj->my_dev;
obj->dirty = 1;
yaffs_load_current_time(obj, 0, 1);
if (dev->param.defered_dir_update) {
struct list_head *link = &obj->variant.dir_variant.dirty;
if (list_empty(link)) {
list_add(link, &dev->dirty_dirs);
yaffs_trace(YAFFS_TRACE_BACKGROUND,
"Added object %d to dirty directories",
obj->obj_id);
}
} else {
yaffs_update_oh(obj, NULL, 0, 0, 0, NULL);
}
}
void yaffs_update_dirty_dirs(struct yaffs_dev *dev)
{
struct list_head *link;
struct yaffs_obj *obj;
struct yaffs_dir_var *d_s;
union yaffs_obj_var *o_v;
yaffs_trace(YAFFS_TRACE_BACKGROUND, "Update dirty directories");
while (!list_empty(&dev->dirty_dirs)) {
link = dev->dirty_dirs.next;
list_del_init(link);
d_s = list_entry(link, struct yaffs_dir_var, dirty);
o_v = list_entry(d_s, union yaffs_obj_var, dir_variant);
obj = list_entry(o_v, struct yaffs_obj, variant);
yaffs_trace(YAFFS_TRACE_BACKGROUND, "Update directory %d",
obj->obj_id);
if (obj->dirty)
yaffs_update_oh(obj, NULL, 0, 0, 0, NULL);
}
}
/*
* Mknod (create) a new object.
* equiv_obj only has meaning for a hard link;
* alias_str only has meaning for a symlink.
* rdev only has meaning for devices (a subset of special objects)
*/
static struct yaffs_obj *yaffs_create_obj(enum yaffs_obj_type type,
struct yaffs_obj *parent,
const YCHAR *name,
u32 mode,
u32 uid,
u32 gid,
struct yaffs_obj *equiv_obj,
const YCHAR *alias_str, u32 rdev)
{
struct yaffs_obj *in;
YCHAR *str = NULL;
struct yaffs_dev *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(alias_str);
if (!str)
return NULL;
}
in = yaffs_new_obj(dev, -1, type);
if (!in) {
kfree(str);
return NULL;
}
in->hdr_chunk = 0;
in->valid = 1;
in->variant_type = type;
in->yst_mode = mode;
yaffs_attribs_init(in, gid, uid, rdev);
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;
list_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 */
yaffs_del_obj(in);
in = NULL;
}
if (in)
yaffs_update_parent(parent);
return in;
}
struct yaffs_obj *yaffs_create_file(struct yaffs_obj *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);
}
struct yaffs_obj *yaffs_create_dir(struct yaffs_obj *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);
}
struct yaffs_obj *yaffs_create_special(struct yaffs_obj *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);
}
struct yaffs_obj *yaffs_create_symlink(struct yaffs_obj *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.*/
struct yaffs_obj *yaffs_link_obj(struct yaffs_obj *parent, const YCHAR * name,
struct yaffs_obj *equiv_obj)
{
/* Get the real object in case we were fed a hard link obj */
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;
return NULL;
}
/*---------------------- Block Management and Page Allocation -------------*/
static void yaffs_deinit_blocks(struct yaffs_dev *dev)
{
if (dev->block_info_alt && dev->block_info)
vfree(dev->block_info);
else
kfree(dev->block_info);
dev->block_info_alt = 0;
dev->block_info = NULL;
if (dev->chunk_bits_alt && dev->chunk_bits)
vfree(dev->chunk_bits);
else
kfree(dev->chunk_bits);
dev->chunk_bits_alt = 0;
dev->chunk_bits = NULL;
}
static int yaffs_init_blocks(struct yaffs_dev *dev)
{
int n_blocks = 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 =
kmalloc(n_blocks * sizeof(struct yaffs_block_info), GFP_NOFS);
if (!dev->block_info) {
dev->block_info =
vmalloc(n_blocks * sizeof(struct yaffs_block_info));
dev->block_info_alt = 1;
} else {
dev->block_info_alt = 0;
}
if (!dev->block_info)
goto alloc_error;
/* Set up dynamic blockinfo stuff. Round up bytes. */
dev->chunk_bit_stride = (dev->param.chunks_per_block + 7) / 8;
dev->chunk_bits =
kmalloc(dev->chunk_bit_stride * n_blocks, GFP_NOFS);
if (!dev->chunk_bits) {
dev->chunk_bits =
vmalloc(dev->chunk_bit_stride * n_blocks);
dev->chunk_bits_alt = 1;
} else {
dev->chunk_bits_alt = 0;
}
if (!dev->chunk_bits)
goto alloc_error;
memset(dev->block_info, 0, n_blocks * sizeof(struct yaffs_block_info));
memset(dev->chunk_bits, 0, dev->chunk_bit_stride * n_blocks);
return YAFFS_OK;
alloc_error:
yaffs_deinit_blocks(dev);
return YAFFS_FAIL;
}
void yaffs_block_became_dirty(struct yaffs_dev *dev, int block_no)
{
struct yaffs_block_info *bi = yaffs_get_block_info(dev, block_no);
int erased_ok = 0;
int i;
/* If the block is still healthy erase it and mark as clean.
* If the block has had a data failure, then retire it.
*/
yaffs_trace(YAFFS_TRACE_GC | YAFFS_TRACE_ERASE,
"yaffs_block_became_dirty block %d state %d %s",
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 */
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);
erased_ok = yaffs_erase_block(dev, block_no);
if (!erased_ok) {
dev->n_erase_failures++;
yaffs_trace(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,
"**>> Erasure failed %d", block_no);
}
}
/* Verify erasure if needed */
if (erased_ok &&
((yaffs_trace_mask & YAFFS_TRACE_ERASE) ||
!yaffs_skip_verification(dev))) {
for (i = 0; i < dev->param.chunks_per_block; i++) {
if (!yaffs_check_chunk_erased(dev,
block_no * dev->param.chunks_per_block + i)) {
yaffs_trace(YAFFS_TRACE_ERROR,
">>Block %d erasure supposedly OK, but chunk %d not erased",
block_no, i);
}
}
}
if (!erased_ok) {
/* We lost a block of free space */
dev->n_free_chunks -= dev->param.chunks_per_block;
yaffs_retire_block(dev, block_no);
yaffs_trace(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,
"**>> Block %d retired", block_no);
return;
}
/* 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; /* Clean, so no need to check */
bi->gc_prioritise = 0;
bi->has_summary = 0;
yaffs_clear_chunk_bits(dev, block_no);
yaffs_trace(YAFFS_TRACE_ERASE, "Erased block %d", block_no);
}
static inline int yaffs_gc_process_chunk(struct yaffs_dev *dev,
struct yaffs_block_info *bi,
int old_chunk, u8 *buffer)
{
int new_chunk;
int mark_flash = 1;
struct yaffs_ext_tags tags;
struct yaffs_obj *object;
int matching_chunk;
int ret_val = YAFFS_OK;
memset(&tags, 0, sizeof(tags));
yaffs_rd_chunk_tags_nand(dev, old_chunk,
buffer, &tags);
object = yaffs_find_by_number(dev, tags.obj_id);
yaffs_trace(YAFFS_TRACE_GC_DETAIL,
"Collecting chunk in block %d, %d %d %d ",
dev->gc_chunk, tags.obj_id,
tags.chunk_id, tags.n_bytes);
if (object && !yaffs_skip_verification(dev)) {
if (tags.chunk_id == 0)
matching_chunk =
object->hdr_chunk;
else if (object->soft_del)
/* Defeat the test */
matching_chunk = old_chunk;
else
matching_chunk =
yaffs_find_chunk_in_file
(object, tags.chunk_id,
NULL);
if (old_chunk != matching_chunk)
yaffs_trace(YAFFS_TRACE_ERROR,
"gc: page in gc mismatch: %d %d %d %d",
old_chunk,
matching_chunk,
tags.obj_id,
tags.chunk_id);
}
if (!object) {
yaffs_trace(YAFFS_TRACE_ERROR,
"page %d in gc has no object: %d %d %d ",
old_chunk,
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 obj */
dev->gc_cleanup_list[dev->n_clean_ups] = tags.obj_id;
dev->n_clean_ups++;
}
mark_flash = 0;
} 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 since its
* work is done.
* Also need to clean up
* shadowing.
*/
struct yaffs_obj_hdr *oh;
oh = (struct yaffs_obj_hdr *) 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) {
yaffs_oh_size_load(oh,
object->variant.file_variant.file_size);
tags.extra_file_size =
object->variant.file_variant.file_size;
}
yaffs_verify_oh(object, oh, &tags, 1);
new_chunk =
yaffs_write_new_chunk(dev, (u8 *) oh, &tags, 1);
} else {
new_chunk =
yaffs_write_new_chunk(dev, buffer, &tags, 1);
}
if (new_chunk < 0) {
ret_val = YAFFS_FAIL;
} else {
/* Now fix up the Tnodes etc. */
if (tags.chunk_id == 0) {
/* It's a header */
object->hdr_chunk = new_chunk;
object->serial = tags.serial_number;
} else {
/* It's a data chunk */
yaffs_put_chunk_in_file(object, tags.chunk_id,
new_chunk, 0);
}
}
}
if (ret_val == YAFFS_OK)
yaffs_chunk_del(dev, old_chunk, mark_flash, __LINE__);
return ret_val;
}
static int yaffs_gc_block(struct yaffs_dev *dev, int block, int whole_block)
{
int old_chunk;
int ret_val = YAFFS_OK;
int i;
int is_checkpt_block;
int max_copies;
int chunks_before = yaffs_get_erased_chunks(dev);
int chunks_after;
struct yaffs_block_info *bi = yaffs_get_block_info(dev, block);
is_checkpt_block = (bi->block_state == YAFFS_BLOCK_STATE_CHECKPOINT);
yaffs_trace(YAFFS_TRACE_TRACING,
"Collecting block %d, in use %d, shrink %d, whole_block %d",
block, bi->pages_in_use, bi->has_shrink_hdr,
whole_block);
/*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;
yaffs_summary_gc(dev, block);
if (is_checkpt_block || !yaffs_still_some_chunks(dev, block)) {
yaffs_trace(YAFFS_TRACE_TRACING,
"Collecting block %d that has no chunks in use",
block);
yaffs_block_became_dirty(dev, block);
} else {
u8 *buffer = yaffs_get_temp_buffer(dev);
yaffs_verify_blk(dev, bi, block);
max_copies = (whole_block) ? dev->param.chunks_per_block : 5;
old_chunk = block * dev->param.chunks_per_block + dev->gc_chunk;
for (/* init already done */ ;
ret_val == YAFFS_OK &&
dev->gc_chunk < dev->param.chunks_per_block &&
(bi->block_state == YAFFS_BLOCK_STATE_COLLECTING) &&
max_copies > 0;
dev->gc_chunk++, old_chunk++) {
if (yaffs_check_chunk_bit(dev, block, dev->gc_chunk)) {
/* Page is in use and might need to be copied */
max_copies--;
ret_val = yaffs_gc_process_chunk(dev, bi,
old_chunk, buffer);
}
}
yaffs_release_temp_buffer(dev, buffer);
}
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 */
struct yaffs_obj *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;
yaffs_trace(YAFFS_TRACE_GC,
"yaffs: About to finally delete object %d",
object->obj_id);
yaffs_generic_obj_del(object);
object->my_dev->n_deleted_files--;
}
}
chunks_after = yaffs_get_erased_chunks(dev);
if (chunks_before >= chunks_after)
yaffs_trace(YAFFS_TRACE_GC,
"gc did not increase free chunks before %d after %d",
chunks_before, chunks_after);
dev->gc_block = 0;
dev->gc_chunk = 0;
dev->n_clean_ups = 0;
}
dev->gc_disable = 0;
return ret_val;
}
/*
* find_gc_block() selects the dirtiest block (or close enough)
* for garbage collection.
*/
static unsigned yaffs_find_gc_block(struct yaffs_dev *dev,
int aggressive, int background)
{
int i;
int iterations;
unsigned selected = 0;
int prioritised = 0;
int prioritised_exist = 0;
struct yaffs_block_info *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) {
prioritised_exist = 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 (prioritised_exist &&
!selected && dev->oldest_dirty_block > 0)
selected = dev->oldest_dirty_block;
if (!prioritised_exist) /* 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 (leasurely gc), then we only bother to do this if the
* block has only a few pages in use.
*/
if (!selected) {
int pages_used;
int n_blocks =
dev->internal_end_block - dev->internal_start_block + 1;
if (aggressive) {
threshold = dev->param.chunks_per_block;
iterations = n_blocks;
} else {
int max_threshold;
if (background)
max_threshold = dev->param.chunks_per_block / 2;
else
max_threshold = dev->param.chunks_per_block / 8;
if (max_threshold < YAFFS_GC_PASSIVE_THRESHOLD)
max_threshold = 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 > max_threshold)
threshold = max_threshold;
iterations = n_blocks / 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);
pages_used = bi->pages_in_use - bi->soft_del_pages;
if (bi->block_state == YAFFS_BLOCK_STATE_FULL &&
pages_used < dev->param.chunks_per_block &&
(dev->gc_dirtiest < 1 ||
pages_used < dev->gc_pages_in_use) &&
yaffs_block_ok_for_gc(dev, bi)) {
dev->gc_dirtiest = dev->gc_block_finder;
dev->gc_pages_in_use = pages_used;
}
}
if (dev->gc_dirtiest > 0 && dev->gc_pages_in_use <= threshold)
selected = dev->gc_dirtiest;
}
/*
* If nothing has been selected for a while, try 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) {
yaffs_trace(YAFFS_TRACE_GC,
"GC Selected block %d with %d free, prioritised:%d",
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++;
yaffs_trace(YAFFS_TRACE_GC,
"GC none: finder %d skip %d threshold %d dirtiest %d using %d oldest %d%s",
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 only accepts 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(struct yaffs_dev *dev, int background)
{
int aggressive = 0;
int gc_ok = YAFFS_OK;
int max_tries = 0;
int min_erased;
int erased_chunks;
int checkpt_block_adjust;
if (dev->param.gc_control_fn &&
(dev->param.gc_control_fn(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.
* Only loops here if the collection does not increase space.
*/
do {
max_tries++;
checkpt_block_adjust = yaffs_calc_checkpt_blocks_required(dev);
min_erased =
dev->param.n_reserved_blocks + checkpt_block_adjust + 1;
erased_chunks =
dev->n_erased_blocks * dev->param.chunks_per_block;
/* If we need a block soon then do aggressive gc. */
if (dev->n_erased_blocks < min_erased)
aggressive = 1;
else {
if (!background
&& erased_chunks > (dev->n_free_chunks / 4))
break;
if (dev->gc_skip > 20)
dev->gc_skip = 20;
if (erased_chunks < 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++;
yaffs_trace(YAFFS_TRACE_GC,
"yaffs: GC n_erased_blocks %d aggressive %d",
dev->n_erased_blocks, aggressive);
gc_ok = yaffs_gc_block(dev, dev->gc_block, aggressive);
}
if (dev->n_erased_blocks < (dev->param.n_reserved_blocks) &&
dev->gc_block > 0) {
yaffs_trace(YAFFS_TRACE_GC,
"yaffs: GC !!!no reclaim!!! n_erased_blocks %d after try %d block %d",
dev->n_erased_blocks, max_tries,
dev->gc_block);
}
} while ((dev->n_erased_blocks < dev->param.n_reserved_blocks) &&
(dev->gc_block > 0) && (max_tries < 2));
return aggressive ? gc_ok : 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(struct yaffs_dev *dev, unsigned urgency)
{
int erased_chunks = dev->n_erased_blocks * dev->param.chunks_per_block;
yaffs_trace(YAFFS_TRACE_BACKGROUND, "Background gc %u", urgency);
yaffs_check_gc(dev, 1);
return erased_chunks > dev->n_free_chunks / 2;
}
/*-------------------- Data file manipulation -----------------*/
static int yaffs_rd_data_obj(struct yaffs_obj *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 {
yaffs_trace(YAFFS_TRACE_NANDACCESS,
"Chunk %d not found zero instead",
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(struct yaffs_dev *dev, int chunk_id, int mark_flash,
int lyn)
{
int block;
int page;
struct yaffs_ext_tags tags;
struct yaffs_block_info *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))
yaffs_trace(YAFFS_TRACE_VERIFY,
"Deleting invalid chunk %d", chunk_id);
bi = yaffs_get_block_info(dev, block);
yaffs2_update_oldest_dirty_seq(dev, block, bi);
yaffs_trace(YAFFS_TRACE_DELETION,
"line %d delete of chunk %d",
lyn, chunk_id);
if (!dev->param.is_yaffs2 && mark_flash &&
bi->block_state != YAFFS_BLOCK_STATE_COLLECTING) {
memset(&tags, 0, sizeof(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_SCAN ||
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_SCAN) {
yaffs_block_became_dirty(dev, block);
}
}
}
static int yaffs_wr_data_obj(struct yaffs_obj *in, int inode_chunk,
const u8 *buffer, int n_bytes, int use_reserve)
{
/* Find old chunk Need to do this to get serial number
* Write new one and patch into tree.
* Invalidate old tags.
*/
int prev_chunk_id;
struct yaffs_ext_tags prev_tags;
int new_chunk_id;
struct yaffs_ext_tags new_tags;
struct yaffs_dev *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.
*/
prev_chunk_id = yaffs_find_chunk_in_file(in, inode_chunk, &prev_tags);
if (prev_chunk_id < 1 &&
!yaffs_put_chunk_in_file(in, inode_chunk, 0, 0))
return 0;
/* Set up new tags */
memset(&new_tags, 0, sizeof(new_tags));
new_tags.chunk_id = inode_chunk;
new_tags.obj_id = in->obj_id;
new_tags.serial_number =
(prev_chunk_id > 0) ? prev_tags.serial_number + 1 : 1;
new_tags.n_bytes = n_bytes;
if (n_bytes < 1 || n_bytes > dev->param.total_bytes_per_chunk) {
yaffs_trace(YAFFS_TRACE_ERROR,
"Writing %d bytes to chunk!!!!!!!!!",
n_bytes);
BUG();
}
new_chunk_id =
yaffs_write_new_chunk(dev, buffer, &new_tags, use_reserve);
if (new_chunk_id > 0) {
yaffs_put_chunk_in_file(in, inode_chunk, new_chunk_id, 0);
if (prev_chunk_id > 0)
yaffs_chunk_del(dev, prev_chunk_id, 1, __LINE__);
yaffs_verify_file_sane(in);
}
return new_chunk_id;
}
static int yaffs_do_xattrib_mod(struct yaffs_obj *obj, int set,
const YCHAR *name, const void *value, int size,
int flags)
{
struct yaffs_xattr_mod xmod;
int result;
xmod.set = set;
xmod.name = name;
xmod.data = value;
xmod.size = size;
xmod.flags = flags;
xmod.result = -ENOSPC;
result = yaffs_update_oh(obj, NULL, 0, 0, 0, &xmod);
if (result > 0)
return xmod.result;
else
return -ENOSPC;
}
static int yaffs_apply_xattrib_mod(struct yaffs_obj *obj, char *buffer,
struct yaffs_xattr_mod *xmod)
{
int retval = 0;
int x_offs = sizeof(struct yaffs_obj_hdr);
struct yaffs_dev *dev = obj->my_dev;
int x_size = dev->data_bytes_per_chunk - sizeof(struct yaffs_obj_hdr);
char *x_buffer = buffer + x_offs;
if (xmod->set)
retval =
nval_set(x_buffer, x_size, xmod->name, xmod->data,
xmod->size, xmod->flags);
else
retval = nval_del(x_buffer, x_size, xmod->name);
obj->has_xattr = nval_hasvalues(x_buffer, x_size);
obj->xattr_known = 1;
xmod->result = retval;
return retval;
}
static int yaffs_do_xattrib_fetch(struct yaffs_obj *obj, const YCHAR *name,
void *value, int size)
{
char *buffer = NULL;
int result;
struct yaffs_ext_tags tags;
struct yaffs_dev *dev = obj->my_dev;
int x_offs = sizeof(struct yaffs_obj_hdr);
int x_size = dev->data_bytes_per_chunk - sizeof(struct yaffs_obj_hdr);
char *x_buffer;
int retval = 0;
if (obj->hdr_chunk < 1)
return -ENODATA;
/* If we know that the object has no xattribs then don't do all the
* reading and parsing.
*/
if (obj->xattr_known && !obj->has_xattr) {
if (name)
return -ENODATA;
else
return 0;
}
buffer = (char *)yaffs_get_temp_buffer(dev);
if (!buffer)
return -ENOMEM;
result =
yaffs_rd_chunk_tags_nand(dev, obj->hdr_chunk, (u8 *) buffer, &tags);
if (result != YAFFS_OK)
retval = -ENOENT;
else {
x_buffer = buffer + x_offs;
if (!obj->xattr_known) {
obj->has_xattr = nval_hasvalues(x_buffer, x_size);
obj->xattr_known = 1;
}
if (name)
retval = nval_get(x_buffer, x_size, name, value, size);
else
retval = nval_list(x_buffer, x_size, value, size);
}
yaffs_release_temp_buffer(dev, (u8 *) buffer);
return retval;
}
int yaffs_set_xattrib(struct yaffs_obj *obj, const YCHAR * name,
const void *value, int size, int flags)
{
return yaffs_do_xattrib_mod(obj, 1, name, value, size, flags);
}
int yaffs_remove_xattrib(struct yaffs_obj *obj, const YCHAR * name)
{
return yaffs_do_xattrib_mod(obj, 0, name, NULL, 0, 0);
}
int yaffs_get_xattrib(struct yaffs_obj *obj, const YCHAR * name, void *value,
int size)
{
return yaffs_do_xattrib_fetch(obj, name, value, size);
}
int yaffs_list_xattrib(struct yaffs_obj *obj, char *buffer, int size)
{
return yaffs_do_xattrib_fetch(obj, NULL, buffer, size);
}
static void yaffs_check_obj_details_loaded(struct yaffs_obj *in)
{
u8 *buf;
struct yaffs_obj_hdr *oh;
struct yaffs_dev *dev;
struct yaffs_ext_tags tags;
int result;
int alloc_failed = 0;
if (!in || !in->lazy_loaded || in->hdr_chunk < 1)
return;
dev = in->my_dev;
in->lazy_loaded = 0;
buf = yaffs_get_temp_buffer(dev);
result = yaffs_rd_chunk_tags_nand(dev, in->hdr_chunk, buf, &tags);
oh = (struct yaffs_obj_hdr *)buf;
in->yst_mode = oh->yst_mode;
yaffs_load_attribs(in, oh);
yaffs_set_obj_name_from_oh(in, oh);
if (in->variant_type == YAFFS_OBJECT_TYPE_SYMLINK) {