From 716ca530e1c4515d8683c9d5be3d56b301758b66 Mon Sep 17 00:00:00 2001 From: James <> Date: Wed, 4 Nov 2015 11:49:21 +0000 Subject: trunk-47381 --- .../generic/files/fs/yaffs2/yaffs_allocator.c | 357 +++++++++++++++++++++ 1 file changed, 357 insertions(+) create mode 100644 target/linux/generic/files/fs/yaffs2/yaffs_allocator.c (limited to 'target/linux/generic/files/fs/yaffs2/yaffs_allocator.c') diff --git a/target/linux/generic/files/fs/yaffs2/yaffs_allocator.c b/target/linux/generic/files/fs/yaffs2/yaffs_allocator.c new file mode 100644 index 0000000..c8f2861 --- /dev/null +++ b/target/linux/generic/files/fs/yaffs2/yaffs_allocator.c @@ -0,0 +1,357 @@ +/* + * 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 + * + * 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); + } +} + -- cgit v1.2.3