--- /dev/null
+/*
+ * 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);
+ }
+}
Code Review / kvmfornfv.git / blobdiff