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| void yaffs_update_dirty_dirs(struct yaffs_dev *dev)
{
........
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);
if (obj->dirty)
yaffs_update_oh(obj, NULL, 0, 0, 0, NULL);
}
}
int yaffs_update_oh(struct yaffs_obj \*in, const YCHAR \*name, int force,int is_shrink, int shadows, struct yaffs_xattr_mod *xmod)
{
strcpy(old_name, _Y("silly old name"));
if (in->fake && in != dev->root_dir && !force && !xmod)
return ret_val;
yaffs_check_gc(dev, 0);
yaffs_check_obj_details_loaded(in);
buffer = yaffs_get_temp_buffer(in->my_dev);
oh = (struct yaffs_obj_hdr *)buffer;
prev_chunk_id = in->hdr_chunk;
if (prev_chunk_id > 0) {
result = yaffs_rd_chunk_tags_nand(dev, prev_chunk_id,buffer, &old_tags);
if (result == YAFFS_OK) {
yaffs_verify_oh(in, oh, &old_tags, 0);
memcpy(old_name, oh->name, sizeof(oh->name));
memset(oh, 0xff, sizeof(*oh));
}
} 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;
yaffs_load_attribs_oh(oh, in);
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 (prev_chunk_id > 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:
break;
case YAFFS_OBJECT_TYPE_FILE:
if (oh->parent_obj_id != YAFFS_OBJECTID_DELETED &&
oh->parent_obj_id != YAFFS_OBJECTID_UNLINKED)
file_size = in->variant.file_variant.stored_size;
yaffs_oh_size_load(dev, oh, file_size, 0);
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");
strncpy(oh->alias, alias, YAFFS_MAX_ALIAS_LENGTH);
oh->alias[YAFFS_MAX_ALIAS_LENGTH] = 0;
break;
}
if (xmod)
yaffs_apply_xattrib_mod(in, (char *)buffer, xmod);
memset(&new_tags, 0, sizeof(new_tags));
in->serial++;
new_tags.chunk_id = 0;
new_tags.obj_id = in->obj_id;
new_tags.serial_number = in->serial;
new_tags.extra_available = 1;
new_tags.extra_parent_id = oh->parent_obj_id;
new_tags.extra_file_size = file_size;
new_tags.extra_is_shrink = oh->is_shrink;
new_tags.extra_equiv_id = oh->equiv_id;
new_tags.extra_shadows = (oh->shadows_obj > 0) ? 1 : 0;
new_tags.extra_obj_type = in->variant_type;
yaffs_do_endian_oh(dev, oh);
yaffs_verify_oh(in, oh, &new_tags, 1);
new_chunk_id = yaffs_write_new_chunk(dev, buffer, &new_tags,(prev_chunk_id > 0) ? 1 : 0);
if (buffer) yaffs_release_temp_buffer(dev, buffer);
if (new_chunk_id < 0) return new_chunk_id;
in->hdr_chunk = new_chunk_id;
if (prev_chunk_id > 0) yaffs_chunk_del(dev, prev_chunk_id, 1, __LINE__);
if (!yaffs_obj_cache_dirty(in))
in->dirty = 0;
if (is_shrink) {
bi = yaffs_get_block_info(in->my_dev, new_chunk_id / in->my_dev->param.chunks_per_block);
bi->has_shrink_hdr = 1;
}
return new_chunk_id;
}
紧急程度计算方法见yaffs_bg_gc_urgency函数如下：
static unsigned yaffs_bg_gc_urgency(struct yaffs_dev *dev)
{
unsigned erased_chunks = dev->n_erased_blocks * dev->param.chunks_per_block;
struct yaffs_linux_context *context = yaffs_dev_to_lc(dev);
unsigned scattered = 0;
if (erased_chunks < dev->n_free_chunks) scattered = (dev->n_free_chunks - erased_chunks);
if (!context->bg_running)
return 0;
else if (scattered < (dev->param.chunks_per_block * 2))
return 0;
else if (erased_chunks > dev->n_free_chunks / 2)
return 0;
else if (erased_chunks > dev->n_free_chunks / 4)
return 1;
else
return 2;
}
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