fs/yaffs2/yaffs_allocator.c - u-boot - Git at Google

 /*
  * 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 "yaffs_allocator.h"
 #include "yaffs_guts.h"
 #include "yaffs_trace.h"
 #include "yportenv.h"

 /*
  * Each entry in yaffs_tnode_list and yaffs_obj_list hold blocks
  * of approx 100 objects that are themn allocated singly.
  * This is basically a simplified slab allocator.
  *
  * We don't use the Linux slab allocator because slab does not allow
  * us to dump all the objects in one hit when we do a umount and tear
  * down  all the tnodes and objects. slab requires that we first free
  * the individual objects.
  *
  * Once yaffs has been mainlined I shall try to motivate for a change
  * to slab to provide the extra features we need here.
  */

 struct yaffs_tnode_list {
 	struct yaffs_tnode_list *next;
 	struct yaffs_tnode *tnodes;
 };

 struct yaffs_obj_list {
 	struct yaffs_obj_list *next;
 	struct yaffs_obj *objects;
 };

 struct yaffs_allocator {
 	int n_tnodes_created;
 	struct yaffs_tnode *free_tnodes;
 	int n_free_tnodes;
 	struct yaffs_tnode_list *alloc_tnode_list;

 	int n_obj_created;
 	struct list_head free_objs;
 	int n_free_objects;

 	struct yaffs_obj_list *allocated_obj_list;
 };

 static void yaffs_deinit_raw_tnodes(struct yaffs_dev *dev)
 {
 	struct yaffs_allocator *allocator =
 	    (struct yaffs_allocator *)dev->allocator;
 	struct yaffs_tnode_list *tmp;

 	if (!allocator) {
 		BUG();
 		return;
 	}

 	while (allocator->alloc_tnode_list) {
 		tmp = allocator->alloc_tnode_list->next;

 		kfree(allocator->alloc_tnode_list->tnodes);
 		kfree(allocator->alloc_tnode_list);
 		allocator->alloc_tnode_list = tmp;
 	}

 	allocator->free_tnodes = NULL;
 	allocator->n_free_tnodes = 0;
 	allocator->n_tnodes_created = 0;
 }

 static void yaffs_init_raw_tnodes(struct yaffs_dev *dev)
 {
 	struct yaffs_allocator *allocator = dev->allocator;

 	if (!allocator) {
 		BUG();
 		return;
 	}

 	allocator->alloc_tnode_list = NULL;
 	allocator->free_tnodes = NULL;
 	allocator->n_free_tnodes = 0;
 	allocator->n_tnodes_created = 0;
 }

 static int yaffs_create_tnodes(struct yaffs_dev *dev, int n_tnodes)
 {
 	struct yaffs_allocator *allocator =
 	    (struct yaffs_allocator *)dev->allocator;
 	int i;
 	struct yaffs_tnode *new_tnodes;
 	u8 *mem;
 	struct yaffs_tnode *curr;
 	struct yaffs_tnode *next;
 	struct yaffs_tnode_list *tnl;

 	if (!allocator) {
 		BUG();
 		return YAFFS_FAIL;
 	}

 	if (n_tnodes < 1)
 		return YAFFS_OK;

 	/* make these things */
 	new_tnodes = kmalloc(n_tnodes * dev->tnode_size, GFP_NOFS);
 	mem = (u8 *) new_tnodes;

 	if (!new_tnodes) {
 		yaffs_trace(YAFFS_TRACE_ERROR,
 			"yaffs: Could not allocate Tnodes");
 		return YAFFS_FAIL;
 	}

 	/* New hookup for wide tnodes */
 	for (i = 0; i < n_tnodes - 1; i++) {
 		curr = (struct yaffs_tnode *)&mem[i * dev->tnode_size];
 		next = (struct yaffs_tnode *)&mem[(i + 1) * dev->tnode_size];
 		curr->internal[0] = next;
 	}

 	curr = (struct yaffs_tnode *)&mem[(n_tnodes - 1) * dev->tnode_size];
 	curr->internal[0] = allocator->free_tnodes;
 	allocator->free_tnodes = (struct yaffs_tnode *)mem;

 	allocator->n_free_tnodes += n_tnodes;
 	allocator->n_tnodes_created += n_tnodes;

 	/* Now add this bunch of tnodes to a list for freeing up.
 	 * NB If we can't add this to the management list it isn't fatal
 	 * but it just means we can't free this bunch of tnodes later.
 	 */
 	tnl = kmalloc(sizeof(struct yaffs_tnode_list), GFP_NOFS);
 	if (!tnl) {
 		yaffs_trace(YAFFS_TRACE_ERROR,
 			"Could not add tnodes to management list");
 		return YAFFS_FAIL;
 	} else {
 		tnl->tnodes = new_tnodes;
 		tnl->next = allocator->alloc_tnode_list;
 		allocator->alloc_tnode_list = tnl;
 	}

 	yaffs_trace(YAFFS_TRACE_ALLOCATE, "Tnodes added");

 	return YAFFS_OK;
 }

 struct yaffs_tnode *yaffs_alloc_raw_tnode(struct yaffs_dev *dev)
 {
 	struct yaffs_allocator *allocator =
 	    (struct yaffs_allocator *)dev->allocator;
 	struct yaffs_tnode *tn = NULL;

 	if (!allocator) {
 		BUG();
 		return NULL;
 	}

 	/* If there are none left make more */
 	if (!allocator->free_tnodes)
 		yaffs_create_tnodes(dev, YAFFS_ALLOCATION_NTNODES);

 	if (allocator->free_tnodes) {
 		tn = allocator->free_tnodes;
 		allocator->free_tnodes = allocator->free_tnodes->internal[0];
 		allocator->n_free_tnodes--;
 	}

 	return tn;
 }

 /* FreeTnode frees up a tnode and puts it back on the free list */
 void yaffs_free_raw_tnode(struct yaffs_dev *dev, struct yaffs_tnode *tn)
 {
 	struct yaffs_allocator *allocator = dev->allocator;

 	if (!allocator) {
 		BUG();
 		return;
 	}

 	if (tn) {
 		tn->internal[0] = allocator->free_tnodes;
 		allocator->free_tnodes = tn;
 		allocator->n_free_tnodes++;
 	}
 	dev->checkpoint_blocks_required = 0;	/* force recalculation */
 }

 /*--------------- yaffs_obj alloaction ------------------------
  *
  * Free yaffs_objs are stored in a list using obj->siblings.
  * The blocks of allocated objects are stored in a linked list.
  */

 static void yaffs_init_raw_objs(struct yaffs_dev *dev)
 {
 	struct yaffs_allocator *allocator = dev->allocator;

 	if (!allocator) {
 		BUG();
 		return;
 	}

 	allocator->allocated_obj_list = NULL;
 	INIT_LIST_HEAD(&allocator->free_objs);
 	allocator->n_free_objects = 0;
 }

 static void yaffs_deinit_raw_objs(struct yaffs_dev *dev)
 {
 	struct yaffs_allocator *allocator = dev->allocator;
 	struct yaffs_obj_list *tmp;

 	if (!allocator) {
 		BUG();
 		return;
 	}

 	while (allocator->allocated_obj_list) {
 		tmp = allocator->allocated_obj_list->next;
 		kfree(allocator->allocated_obj_list->objects);
 		kfree(allocator->allocated_obj_list);
 		allocator->allocated_obj_list = tmp;
 	}

 	INIT_LIST_HEAD(&allocator->free_objs);
 	allocator->n_free_objects = 0;
 	allocator->n_obj_created = 0;
 }

 static int yaffs_create_free_objs(struct yaffs_dev *dev, int n_obj)
 {
 	struct yaffs_allocator *allocator = dev->allocator;
 	int i;
 	struct yaffs_obj *new_objs;
 	struct yaffs_obj_list *list;

 	if (!allocator) {
 		BUG();
 		return YAFFS_FAIL;
 	}

 	if (n_obj < 1)
 		return YAFFS_OK;

 	/* make these things */
 	new_objs = kmalloc(n_obj * sizeof(struct yaffs_obj), GFP_NOFS);
 	list = kmalloc(sizeof(struct yaffs_obj_list), GFP_NOFS);

 	if (!new_objs || !list) {
 		kfree(new_objs);
 		new_objs = NULL;
 		kfree(list);
 		list = NULL;
 		yaffs_trace(YAFFS_TRACE_ALLOCATE,
 			"Could not allocate more objects");
 		return YAFFS_FAIL;
 	}

 	/* Hook them into the free list */
 	for (i = 0; i < n_obj; i++)
 		list_add(&new_objs[i].siblings, &allocator->free_objs);

 	allocator->n_free_objects += n_obj;
 	allocator->n_obj_created += n_obj;

 	/* Now add this bunch of Objects to a list for freeing up. */

 	list->objects = new_objs;
 	list->next = allocator->allocated_obj_list;
 	allocator->allocated_obj_list = list;

 	return YAFFS_OK;
 }

 struct yaffs_obj *yaffs_alloc_raw_obj(struct yaffs_dev *dev)
 {
 	struct yaffs_obj *obj = NULL;
 	struct list_head *lh;
 	struct yaffs_allocator *allocator = dev->allocator;

 	if (!allocator) {
 		BUG();
 		return obj;
 	}

 	/* If there are none left make more */
 	if (list_empty(&allocator->free_objs))
 		yaffs_create_free_objs(dev, YAFFS_ALLOCATION_NOBJECTS);

 	if (!list_empty(&allocator->free_objs)) {
 		lh = allocator->free_objs.next;
 		obj = list_entry(lh, struct yaffs_obj, siblings);
 		list_del_init(lh);
 		allocator->n_free_objects--;
 	}

 	return obj;
 }

 void yaffs_free_raw_obj(struct yaffs_dev *dev, struct yaffs_obj *obj)
 {

 	struct yaffs_allocator *allocator = dev->allocator;

 	if (!allocator) {
 		BUG();
 		return;
 	}

 	/* Link into the free list. */
 	list_add(&obj->siblings, &allocator->free_objs);
 	allocator->n_free_objects++;
 }

 void yaffs_deinit_raw_tnodes_and_objs(struct yaffs_dev *dev)
 {

 	if (!dev->allocator) {
 		BUG();
 		return;
 	}

 	yaffs_deinit_raw_tnodes(dev);
 	yaffs_deinit_raw_objs(dev);
 	kfree(dev->allocator);
 	dev->allocator = NULL;
 }

 void yaffs_init_raw_tnodes_and_objs(struct yaffs_dev *dev)
 {
 	struct yaffs_allocator *allocator;

 	if (dev->allocator) {
 		BUG();
 		return;
 	}

 	allocator = kmalloc(sizeof(struct yaffs_allocator), GFP_NOFS);
 	if (allocator) {
 		dev->allocator = allocator;
 		yaffs_init_raw_tnodes(dev);
 		yaffs_init_raw_objs(dev);
 	}
 }
	/*
	* 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 "yaffs_allocator.h"
	#include "yaffs_guts.h"
	#include "yaffs_trace.h"
	#include "yportenv.h"

	/*
	* Each entry in yaffs_tnode_list and yaffs_obj_list hold blocks
	* of approx 100 objects that are themn allocated singly.
	* This is basically a simplified slab allocator.
	*
	* We don't use the Linux slab allocator because slab does not allow
	* us to dump all the objects in one hit when we do a umount and tear
	* down all the tnodes and objects. slab requires that we first free
	* the individual objects.
	*
	* Once yaffs has been mainlined I shall try to motivate for a change
	* to slab to provide the extra features we need here.
	*/

	struct yaffs_tnode_list {
	struct yaffs_tnode_list *next;
	struct yaffs_tnode *tnodes;
	};

	struct yaffs_obj_list {
	struct yaffs_obj_list *next;
	struct yaffs_obj *objects;
	};

	struct yaffs_allocator {
	int n_tnodes_created;
	struct yaffs_tnode *free_tnodes;
	int n_free_tnodes;
	struct yaffs_tnode_list *alloc_tnode_list;

	int n_obj_created;
	struct list_head free_objs;
	int n_free_objects;

	struct yaffs_obj_list *allocated_obj_list;
	};

	static void yaffs_deinit_raw_tnodes(struct yaffs_dev *dev)
	{
	struct yaffs_allocator *allocator =
	(struct yaffs_allocator *)dev->allocator;
	struct yaffs_tnode_list *tmp;

	if (!allocator) {
	BUG();
	return;
	}

	while (allocator->alloc_tnode_list) {
	tmp = allocator->alloc_tnode_list->next;

	kfree(allocator->alloc_tnode_list->tnodes);
	kfree(allocator->alloc_tnode_list);
	allocator->alloc_tnode_list = tmp;
	}

	allocator->free_tnodes = NULL;
	allocator->n_free_tnodes = 0;
	allocator->n_tnodes_created = 0;
	}

	static void yaffs_init_raw_tnodes(struct yaffs_dev *dev)
	{
	struct yaffs_allocator *allocator = dev->allocator;

	if (!allocator) {
	BUG();
	return;
	}

	allocator->alloc_tnode_list = NULL;
	allocator->free_tnodes = NULL;
	allocator->n_free_tnodes = 0;
	allocator->n_tnodes_created = 0;
	}

	static int yaffs_create_tnodes(struct yaffs_dev *dev, int n_tnodes)
	{
	struct yaffs_allocator *allocator =
	(struct yaffs_allocator *)dev->allocator;
	int i;
	struct yaffs_tnode *new_tnodes;
	u8 *mem;
	struct yaffs_tnode *curr;
	struct yaffs_tnode *next;
	struct yaffs_tnode_list *tnl;

	if (!allocator) {
	BUG();
	return YAFFS_FAIL;
	}

	if (n_tnodes < 1)
	return YAFFS_OK;

	/* make these things */
	new_tnodes = kmalloc(n_tnodes * dev->tnode_size, GFP_NOFS);
	mem = (u8 *) new_tnodes;

	if (!new_tnodes) {
	yaffs_trace(YAFFS_TRACE_ERROR,
	"yaffs: Could not allocate Tnodes");
	return YAFFS_FAIL;
	}

	/* New hookup for wide tnodes */
	for (i = 0; i < n_tnodes - 1; i++) {
	curr = (struct yaffs_tnode )&mem[i dev->tnode_size];
	next = (struct yaffs_tnode )&mem[(i + 1) dev->tnode_size];
	curr->internal[0] = next;
	}

	curr = (struct yaffs_tnode )&mem[(n_tnodes - 1) dev->tnode_size];
	curr->internal[0] = allocator->free_tnodes;
	allocator->free_tnodes = (struct yaffs_tnode *)mem;

	allocator->n_free_tnodes += n_tnodes;
	allocator->n_tnodes_created += n_tnodes;

	/* Now add this bunch of tnodes to a list for freeing up.
	* NB If we can't add this to the management list it isn't fatal
	* but it just means we can't free this bunch of tnodes later.
	*/
	tnl = kmalloc(sizeof(struct yaffs_tnode_list), GFP_NOFS);
	if (!tnl) {
	yaffs_trace(YAFFS_TRACE_ERROR,
	"Could not add tnodes to management list");
	return YAFFS_FAIL;
	} else {
	tnl->tnodes = new_tnodes;
	tnl->next = allocator->alloc_tnode_list;
	allocator->alloc_tnode_list = tnl;
	}

	yaffs_trace(YAFFS_TRACE_ALLOCATE, "Tnodes added");

	return YAFFS_OK;
	}

	struct yaffs_tnode yaffs_alloc_raw_tnode(struct yaffs_dev dev)
	{
	struct yaffs_allocator *allocator =
	(struct yaffs_allocator *)dev->allocator;
	struct yaffs_tnode *tn = NULL;

	if (!allocator) {
	BUG();
	return NULL;
	}

	/* If there are none left make more */
	if (!allocator->free_tnodes)
	yaffs_create_tnodes(dev, YAFFS_ALLOCATION_NTNODES);

	if (allocator->free_tnodes) {
	tn = allocator->free_tnodes;
	allocator->free_tnodes = allocator->free_tnodes->internal[0];
	allocator->n_free_tnodes--;
	}

	return tn;
	}

	/* FreeTnode frees up a tnode and puts it back on the free list */
	void yaffs_free_raw_tnode(struct yaffs_dev dev, struct yaffs_tnode tn)
	{
	struct yaffs_allocator *allocator = dev->allocator;

	if (!allocator) {
	BUG();
	return;
	}

	if (tn) {
	tn->internal[0] = allocator->free_tnodes;
	allocator->free_tnodes = tn;
	allocator->n_free_tnodes++;
	}
	dev->checkpoint_blocks_required = 0; /* force recalculation */
	}

	/*--------------- yaffs_obj alloaction ------------------------
	*
	* Free yaffs_objs are stored in a list using obj->siblings.
	* The blocks of allocated objects are stored in a linked list.
	*/

	static void yaffs_init_raw_objs(struct yaffs_dev *dev)
	{
	struct yaffs_allocator *allocator = dev->allocator;

	if (!allocator) {
	BUG();
	return;
	}

	allocator->allocated_obj_list = NULL;
	INIT_LIST_HEAD(&allocator->free_objs);
	allocator->n_free_objects = 0;
	}

	static void yaffs_deinit_raw_objs(struct yaffs_dev *dev)
	{
	struct yaffs_allocator *allocator = dev->allocator;
	struct yaffs_obj_list *tmp;

	if (!allocator) {
	BUG();
	return;
	}

	while (allocator->allocated_obj_list) {
	tmp = allocator->allocated_obj_list->next;
	kfree(allocator->allocated_obj_list->objects);
	kfree(allocator->allocated_obj_list);
	allocator->allocated_obj_list = tmp;
	}

	INIT_LIST_HEAD(&allocator->free_objs);
	allocator->n_free_objects = 0;
	allocator->n_obj_created = 0;
	}

	static int yaffs_create_free_objs(struct yaffs_dev *dev, int n_obj)
	{
	struct yaffs_allocator *allocator = dev->allocator;
	int i;
	struct yaffs_obj *new_objs;
	struct yaffs_obj_list *list;

	if (!allocator) {
	BUG();
	return YAFFS_FAIL;
	}

	if (n_obj < 1)
	return YAFFS_OK;

	/* make these things */
	new_objs = kmalloc(n_obj * sizeof(struct yaffs_obj), GFP_NOFS);
	list = kmalloc(sizeof(struct yaffs_obj_list), GFP_NOFS);

	if (!new_objs \|\| !list) {
	kfree(new_objs);
	new_objs = NULL;
	kfree(list);
	list = NULL;
	yaffs_trace(YAFFS_TRACE_ALLOCATE,
	"Could not allocate more objects");
	return YAFFS_FAIL;
	}

	/* Hook them into the free list */
	for (i = 0; i < n_obj; i++)
	list_add(&new_objs[i].siblings, &allocator->free_objs);

	allocator->n_free_objects += n_obj;
	allocator->n_obj_created += n_obj;

	/* Now add this bunch of Objects to a list for freeing up. */

	list->objects = new_objs;
	list->next = allocator->allocated_obj_list;
	allocator->allocated_obj_list = list;

	return YAFFS_OK;
	}

	struct yaffs_obj yaffs_alloc_raw_obj(struct yaffs_dev dev)
	{
	struct yaffs_obj *obj = NULL;
	struct list_head *lh;
	struct yaffs_allocator *allocator = dev->allocator;

	if (!allocator) {
	BUG();
	return obj;
	}

	/* If there are none left make more */
	if (list_empty(&allocator->free_objs))
	yaffs_create_free_objs(dev, YAFFS_ALLOCATION_NOBJECTS);

	if (!list_empty(&allocator->free_objs)) {
	lh = allocator->free_objs.next;
	obj = list_entry(lh, struct yaffs_obj, siblings);
	list_del_init(lh);
	allocator->n_free_objects--;
	}

	return obj;
	}

	void yaffs_free_raw_obj(struct yaffs_dev dev, struct yaffs_obj obj)
	{

	struct yaffs_allocator *allocator = dev->allocator;

	if (!allocator) {
	BUG();
	return;
	}

	/* Link into the free list. */
	list_add(&obj->siblings, &allocator->free_objs);
	allocator->n_free_objects++;
	}

	void yaffs_deinit_raw_tnodes_and_objs(struct yaffs_dev *dev)
	{

	if (!dev->allocator) {
	BUG();
	return;
	}

	yaffs_deinit_raw_tnodes(dev);
	yaffs_deinit_raw_objs(dev);
	kfree(dev->allocator);
	dev->allocator = NULL;
	}

	void yaffs_init_raw_tnodes_and_objs(struct yaffs_dev *dev)
	{
	struct yaffs_allocator *allocator;

	if (dev->allocator) {
	BUG();
	return;
	}

	allocator = kmalloc(sizeof(struct yaffs_allocator), GFP_NOFS);
	if (allocator) {
	dev->allocator = allocator;
	yaffs_init_raw_tnodes(dev);
	yaffs_init_raw_objs(dev);
	}
	}