yaffs: Clean up as per Ryan's comments
[yaffs2.git] / yaffs_allocator.c
index c0513d5..695c254 100644 (file)
@@ -1,5 +1,5 @@
 /*
- * YAFFS: Yet another Flash File System . A NAND-flash specific file system.
+ * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
  *
  * Copyright (C) 2002-2010 Aleph One Ltd.
  *   for Toby Churchill Ltd and Brightstar Engineering
  * Created by Charles Manning <charles@aleph1.co.uk>
  *
  * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU Lesser General Public License version 2.1 as
+ * it under the terms of the GNU General Public License version 2 as
  * published by the Free Software Foundation.
- *
- * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
  */
 
-
 #include "yaffs_allocator.h"
 #include "yaffs_guts.h"
 #include "yaffs_trace.h"
 #include "yportenv.h"
 
-#ifdef CONFIG_YAFFS_YMALLOC_ALLOCATOR
-
-void yaffs_deinit_raw_tnodes_and_objs(yaffs_dev_t *dev)
-{
-       dev = dev;
-}
-
-void yaffs_init_raw_tnodes_and_objs(yaffs_dev_t *dev)
-{
-       dev = dev;
-}
-
-yaffs_tnode_t *yaffs_alloc_raw_tnode(yaffs_dev_t *dev)
-{
-       return (yaffs_tnode_t *)YMALLOC(dev->tnode_size);
-}
-
-void yaffs_free_raw_tnode(yaffs_dev_t *dev, yaffs_tnode_t *tn)
-{
-       dev = dev;
-       YFREE(tn);
-}
-
-void yaffs_init_raw_objs(yaffs_dev_t *dev)
-{
-       dev = dev;
-}
-
-void yaffs_deinit_raw_objs(yaffs_dev_t *dev)
-{
-       dev = dev;
-}
-
-yaffs_obj_t *yaffs_alloc_raw_obj(yaffs_dev_t *dev)
-{
-       dev = dev;
-       return (yaffs_obj_t *) YMALLOC(sizeof(yaffs_obj_t));
-}
-
-
-void yaffs_free_raw_obj(yaffs_dev_t *dev, yaffs_obj_t *obj)
-{
-
-       dev = dev;
-       YFREE(obj);
-}
-
-#else
+/*
+ * 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;
-       yaffs_tnode_t *tnodes;
+       struct yaffs_tnode *tnodes;
 };
 
-typedef struct yaffs_tnode_list yaffs_tnodelist_t;
-
-struct yaffs_obj_tList_struct {
-       yaffs_obj_t *objects;
-       struct yaffs_obj_tList_struct *next;
+struct yaffs_obj_list {
+       struct yaffs_obj_list *next;
+       struct yaffs_obj *objects;
 };
 
-typedef struct yaffs_obj_tList_struct yaffs_obj_tList;
-
+struct yaffs_allocator {
+       int n_tnodes_created;
+       struct yaffs_tnode *free_tnodes;
+       int n_free_tnodes;
+       struct yaffs_tnode_list *alloc_tnode_list;
 
-struct yaffs_AllocatorStruct {
-       int n_tnodesCreated;
-       yaffs_tnode_t *freeTnodes;
-       int nFreeTnodes;
-       yaffs_tnodelist_t *allocatedTnodeList;
+       int n_obj_created;
+       struct list_head free_objs;
+       int n_free_objects;
 
-       int n_objCreated;
-       yaffs_obj_t *freeObjects;
-       int nFreeObjects;
-
-       yaffs_obj_tList *allocatedObjectList;
+       struct yaffs_obj_list *allocated_obj_list;
 };
 
-typedef struct yaffs_AllocatorStruct yaffs_Allocator;
-
-
-static void yaffs_deinit_raw_tnodes(yaffs_dev_t *dev)
+static void yaffs_deinit_raw_tnodes(struct yaffs_dev *dev)
 {
+       struct yaffs_allocator *allocator =
+           (struct yaffs_allocator *)dev->allocator;
+       struct yaffs_tnode_list *tmp;
 
-       yaffs_Allocator *allocator = (yaffs_Allocator *)dev->allocator;
-
-       yaffs_tnodelist_t *tmp;
-
-       if(!allocator){
-               YBUG();
+       if (!allocator) {
+               BUG();
                return;
        }
 
-       while (allocator->allocatedTnodeList) {
-               tmp = allocator->allocatedTnodeList->next;
-
-               YFREE(allocator->allocatedTnodeList->tnodes);
-               YFREE(allocator->allocatedTnodeList);
-               allocator->allocatedTnodeList = tmp;
+       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->freeTnodes = NULL;
-       allocator->nFreeTnodes = 0;
-       allocator->n_tnodesCreated = 0;
+       allocator->free_tnodes = NULL;
+       allocator->n_free_tnodes = 0;
+       allocator->n_tnodes_created = 0;
 }
 
-static void yaffs_init_raw_tnodes(yaffs_dev_t *dev)
+static void yaffs_init_raw_tnodes(struct yaffs_dev *dev)
 {
-       yaffs_Allocator *allocator = dev->allocator;
-
-       if(allocator){
-               allocator->allocatedTnodeList = NULL;
-               allocator->freeTnodes = NULL;
-               allocator->nFreeTnodes = 0;
-               allocator->n_tnodesCreated = 0;
-       } else
-               YBUG();
+       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(yaffs_dev_t *dev, int n_tnodes)
+static int yaffs_create_tnodes(struct yaffs_dev *dev, int n_tnodes)
 {
-       yaffs_Allocator *allocator = (yaffs_Allocator *)dev->allocator;
+       struct yaffs_allocator *allocator =
+           (struct yaffs_allocator *)dev->allocator;
        int i;
-       yaffs_tnode_t *newTnodes;
-       __u8 *mem;
-       yaffs_tnode_t *curr;
-       yaffs_tnode_t *next;
-       yaffs_tnodelist_t *tnl;
-
-       if(!allocator){
-               YBUG();
+       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;
 
-       newTnodes = YMALLOC(n_tnodes * dev->tnode_size);
-       mem = (__u8 *)newTnodes;
-
-       if (!newTnodes) {
-               T(YAFFS_TRACE_ERROR,
-                       (TSTR("yaffs: Could not allocate Tnodes" TENDSTR)));
+       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 = (yaffs_tnode_t *) &mem[i * dev->tnode_size];
-               next = (yaffs_tnode_t *) &mem[(i+1) * dev->tnode_size];
+               curr = (struct yaffs_tnode *)&mem[i * dev->tnode_size];
+               next = (struct yaffs_tnode *)&mem[(i + 1) * dev->tnode_size];
                curr->internal[0] = next;
        }
 
-       curr = (yaffs_tnode_t *) &mem[(n_tnodes - 1) * dev->tnode_size];
-       curr->internal[0] = allocator->freeTnodes;
-       allocator->freeTnodes = (yaffs_tnode_t *)mem;
+       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->nFreeTnodes += n_tnodes;
-       allocator->n_tnodesCreated += n_tnodes;
+       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 = YMALLOC(sizeof(yaffs_tnodelist_t));
+       tnl = kmalloc(sizeof(struct yaffs_tnode_list), GFP_NOFS);
        if (!tnl) {
-               T(YAFFS_TRACE_ERROR,
-                 (TSTR
-                  ("yaffs: Could not add tnodes to management list" TENDSTR)));
-                  return YAFFS_FAIL;
+               yaffs_trace(YAFFS_TRACE_ERROR,
+                       "Could not add tnodes to management list");
+               return YAFFS_FAIL;
        } else {
-               tnl->tnodes = newTnodes;
-               tnl->next = allocator->allocatedTnodeList;
-               allocator->allocatedTnodeList = tnl;
+               tnl->tnodes = new_tnodes;
+               tnl->next = allocator->alloc_tnode_list;
+               allocator->alloc_tnode_list = tnl;
        }
 
-       T(YAFFS_TRACE_ALLOCATE, (TSTR("yaffs: Tnodes added" TENDSTR)));
+       yaffs_trace(YAFFS_TRACE_ALLOCATE, "Tnodes added");
 
        return YAFFS_OK;
 }
 
-
-yaffs_tnode_t *yaffs_alloc_raw_tnode(yaffs_dev_t *dev)
+struct yaffs_tnode *yaffs_alloc_raw_tnode(struct yaffs_dev *dev)
 {
-       yaffs_Allocator *allocator = (yaffs_Allocator *)dev->allocator;
-       yaffs_tnode_t *tn = NULL;
+       struct yaffs_allocator *allocator =
+           (struct yaffs_allocator *)dev->allocator;
+       struct yaffs_tnode *tn = NULL;
 
-       if(!allocator){
-               YBUG();
+       if (!allocator) {
+               BUG();
                return NULL;
        }
 
        /* If there are none left make more */
-       if (!allocator->freeTnodes)
+       if (!allocator->free_tnodes)
                yaffs_create_tnodes(dev, YAFFS_ALLOCATION_NTNODES);
 
-       if (allocator->freeTnodes) {
-               tn = allocator->freeTnodes;
-               allocator->freeTnodes = allocator->freeTnodes->internal[0];
-               allocator->nFreeTnodes--;
+       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(yaffs_dev_t *dev, yaffs_tnode_t *tn)
+void yaffs_free_raw_tnode(struct yaffs_dev *dev, struct yaffs_tnode *tn)
 {
-       yaffs_Allocator *allocator = dev->allocator;
+       struct yaffs_allocator *allocator = dev->allocator;
 
-       if(!allocator){
-               YBUG();
+       if (!allocator) {
+               BUG();
                return;
        }
 
        if (tn) {
-               tn->internal[0] = allocator->freeTnodes;
-               allocator->freeTnodes = tn;
-               allocator->nFreeTnodes++;
+               tn->internal[0] = allocator->free_tnodes;
+               allocator->free_tnodes = tn;
+               allocator->n_free_tnodes++;
        }
-       dev->checkpoint_blocks_required = 0; /* force recalculation*/
+       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(yaffs_dev_t *dev)
+static void yaffs_init_raw_objs(struct yaffs_dev *dev)
 {
-       yaffs_Allocator *allocator = dev->allocator;
-
-       if(allocator) {
-               allocator->allocatedObjectList = NULL;
-               allocator->freeObjects = NULL;
-               allocator->nFreeObjects = 0;
-       } else
-               YBUG();
+       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(yaffs_dev_t *dev)
+static void yaffs_deinit_raw_objs(struct yaffs_dev *dev)
 {
-       yaffs_Allocator *allocator = dev->allocator;
-       yaffs_obj_tList *tmp;
+       struct yaffs_allocator *allocator = dev->allocator;
+       struct yaffs_obj_list *tmp;
 
-       if(!allocator){
-               YBUG();
+       if (!allocator) {
+               BUG();
                return;
        }
 
-       while (allocator->allocatedObjectList) {
-               tmp = allocator->allocatedObjectList->next;
-               YFREE(allocator->allocatedObjectList->objects);
-               YFREE(allocator->allocatedObjectList);
-
-               allocator->allocatedObjectList = tmp;
+       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;
        }
 
-       allocator->freeObjects = NULL;
-       allocator->nFreeObjects = 0;
-       allocator->n_objCreated = 0;
+       INIT_LIST_HEAD(&allocator->free_objs);
+       allocator->n_free_objects = 0;
+       allocator->n_obj_created = 0;
 }
 
-
-static int yaffs_create_free_objs(yaffs_dev_t *dev, int n_obj)
+static int yaffs_create_free_objs(struct yaffs_dev *dev, int n_obj)
 {
-       yaffs_Allocator *allocator = dev->allocator;
-
+       struct yaffs_allocator *allocator = dev->allocator;
        int i;
-       yaffs_obj_t *newObjects;
-       yaffs_obj_tList *list;
+       struct yaffs_obj *new_objs;
+       struct yaffs_obj_list *list;
 
-       if(!allocator){
-               YBUG();
+       if (!allocator) {
+               BUG();
                return YAFFS_FAIL;
        }
 
@@ -301,109 +255,103 @@ static int yaffs_create_free_objs(yaffs_dev_t *dev, int n_obj)
                return YAFFS_OK;
 
        /* make these things */
-       newObjects = YMALLOC(n_obj * sizeof(yaffs_obj_t));
-       list = YMALLOC(sizeof(yaffs_obj_tList));
-
-       if (!newObjects || !list) {
-               if (newObjects){
-                       YFREE(newObjects);
-                       newObjects = NULL;
-               }
-               if (list){
-                       YFREE(list);
-                       list = NULL;
-               }
-               T(YAFFS_TRACE_ALLOCATE,
-                 (TSTR("yaffs: Could not allocate more objects" TENDSTR)));
+       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 - 1; i++) {
-               newObjects[i].siblings.next =
-                               (struct ylist_head *)(&newObjects[i + 1]);
-       }
+       for (i = 0; i < n_obj; i++)
+               list_add(&new_objs[i].siblings, &allocator->free_objs);
 
-       newObjects[n_obj - 1].siblings.next = (void *)allocator->freeObjects;
-       allocator->freeObjects = newObjects;
-       allocator->nFreeObjects += n_obj;
-       allocator->n_objCreated += n_obj;
+       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 = newObjects;
-       list->next = allocator->allocatedObjectList;
-       allocator->allocatedObjectList = list;
+       list->objects = new_objs;
+       list->next = allocator->allocated_obj_list;
+       allocator->allocated_obj_list = list;
 
        return YAFFS_OK;
 }
 
-yaffs_obj_t *yaffs_alloc_raw_obj(yaffs_dev_t *dev)
+struct yaffs_obj *yaffs_alloc_raw_obj(struct yaffs_dev *dev)
 {
-       yaffs_obj_t *obj = NULL;
-       yaffs_Allocator *allocator = dev->allocator;
+       struct yaffs_obj *obj = NULL;
+       struct list_head *lh;
+       struct yaffs_allocator *allocator = dev->allocator;
 
-       if(!allocator) {
-               YBUG();
+       if (!allocator) {
+               BUG();
                return obj;
        }
 
        /* If there are none left make more */
-       if (!allocator->freeObjects)
+       if (list_empty(&allocator->free_objs))
                yaffs_create_free_objs(dev, YAFFS_ALLOCATION_NOBJECTS);
 
-       if (allocator->freeObjects) {
-               obj = allocator->freeObjects;
-               allocator->freeObjects =
-                       (yaffs_obj_t *) (allocator->freeObjects->siblings.next);
-               allocator->nFreeObjects--;
+       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(yaffs_dev_t *dev, yaffs_obj_t *obj)
+void yaffs_free_raw_obj(struct yaffs_dev *dev, struct yaffs_obj *obj)
 {
 
-       yaffs_Allocator *allocator = dev->allocator;
+       struct yaffs_allocator *allocator = dev->allocator;
 
-       if(!allocator)
-               YBUG();
-       else {
-               /* Link into the free list. */
-               obj->siblings.next = (struct ylist_head *)(allocator->freeObjects);
-               allocator->freeObjects = obj;
-               allocator->nFreeObjects++;
+       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(yaffs_dev_t *dev)
+void yaffs_deinit_raw_tnodes_and_objs(struct yaffs_dev *dev)
 {
-       if(dev->allocator){
-               yaffs_deinit_raw_tnodes(dev);
-               yaffs_deinit_raw_objs(dev);
-
-               YFREE(dev->allocator);
-               dev->allocator=NULL;
-       } else
-               YBUG();
+
+       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(yaffs_dev_t *dev)
+void yaffs_init_raw_tnodes_and_objs(struct yaffs_dev *dev)
 {
-       yaffs_Allocator *allocator;
-
-       if(!dev->allocator){
-               allocator = YMALLOC(sizeof(yaffs_Allocator));
-               if(allocator){
-                       dev->allocator = allocator;
-                       yaffs_init_raw_tnodes(dev);
-                       yaffs_init_raw_objs(dev);
-               }
-       } else
-               YBUG();
-}
+       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);
+       }
+}
 
-#endif