1/** 2 * Copyright (C) 2008, Creative Technology Ltd. All Rights Reserved. 3 * 4 * This source file is released under GPL v2 license (no other versions). 5 * See the COPYING file included in the main directory of this source 6 * distribution for the license terms and conditions. 7 * 8 * @File ctvmem.c 9 * 10 * @Brief 11 * This file contains the implementation of virtual memory management object 12 * for card device. 13 * 14 * @Author Liu Chun 15 * @Date Apr 1 2008 16 */ 17 18#include "ctvmem.h" 19#include "ctatc.h" 20#include <linux/slab.h> 21#include <linux/mm.h> 22#include <linux/io.h> 23#include <sound/pcm.h> 24 25#define CT_PTES_PER_PAGE (CT_PAGE_SIZE / sizeof(void *)) 26#define CT_ADDRS_PER_PAGE (CT_PTES_PER_PAGE * CT_PAGE_SIZE) 27 28/* * 29 * Find or create vm block based on requested @size. 30 * @size must be page aligned. 31 * */ 32static struct ct_vm_block * 33get_vm_block(struct ct_vm *vm, unsigned int size, struct ct_atc *atc) 34{ 35 struct ct_vm_block *block = NULL, *entry; 36 struct list_head *pos; 37 38 size = CT_PAGE_ALIGN(size); 39 if (size > vm->size) { 40 dev_err(atc->card->dev, 41 "Fail! No sufficient device virtual memory space available!\n"); 42 return NULL; 43 } 44 45 mutex_lock(&vm->lock); 46 list_for_each(pos, &vm->unused) { 47 entry = list_entry(pos, struct ct_vm_block, list); 48 if (entry->size >= size) 49 break; /* found a block that is big enough */ 50 } 51 if (pos == &vm->unused) 52 goto out; 53 54 if (entry->size == size) { 55 /* Move the vm node from unused list to used list directly */ 56 list_move(&entry->list, &vm->used); 57 vm->size -= size; 58 block = entry; 59 goto out; 60 } 61 62 block = kzalloc(sizeof(*block), GFP_KERNEL); 63 if (!block) 64 goto out; 65 66 block->addr = entry->addr; 67 block->size = size; 68 list_add(&block->list, &vm->used); 69 entry->addr += size; 70 entry->size -= size; 71 vm->size -= size; 72 73 out: 74 mutex_unlock(&vm->lock); 75 return block; 76} 77 78static void put_vm_block(struct ct_vm *vm, struct ct_vm_block *block) 79{ 80 struct ct_vm_block *entry, *pre_ent; 81 struct list_head *pos, *pre; 82 83 block->size = CT_PAGE_ALIGN(block->size); 84 85 mutex_lock(&vm->lock); 86 list_del(&block->list); 87 vm->size += block->size; 88 89 list_for_each(pos, &vm->unused) { 90 entry = list_entry(pos, struct ct_vm_block, list); 91 if (entry->addr >= (block->addr + block->size)) 92 break; /* found a position */ 93 } 94 if (pos == &vm->unused) { 95 list_add_tail(&block->list, &vm->unused); 96 entry = block; 97 } else { 98 if ((block->addr + block->size) == entry->addr) { 99 entry->addr = block->addr; 100 entry->size += block->size; 101 kfree(block); 102 } else { 103 __list_add(&block->list, pos->prev, pos); 104 entry = block; 105 } 106 } 107 108 pos = &entry->list; 109 pre = pos->prev; 110 while (pre != &vm->unused) { 111 entry = list_entry(pos, struct ct_vm_block, list); 112 pre_ent = list_entry(pre, struct ct_vm_block, list); 113 if ((pre_ent->addr + pre_ent->size) > entry->addr) 114 break; 115 116 pre_ent->size += entry->size; 117 list_del(pos); 118 kfree(entry); 119 pos = pre; 120 pre = pos->prev; 121 } 122 mutex_unlock(&vm->lock); 123} 124 125/* Map host addr (kmalloced/vmalloced) to device logical addr. */ 126static struct ct_vm_block * 127ct_vm_map(struct ct_vm *vm, struct snd_pcm_substream *substream, int size) 128{ 129 struct ct_vm_block *block; 130 unsigned int pte_start; 131 unsigned i, pages; 132 unsigned long *ptp; 133 struct ct_atc *atc = snd_pcm_substream_chip(substream); 134 135 block = get_vm_block(vm, size, atc); 136 if (block == NULL) { 137 dev_err(atc->card->dev, 138 "No virtual memory block that is big enough to allocate!\n"); 139 return NULL; 140 } 141 142 ptp = (unsigned long *)vm->ptp[0].area; 143 pte_start = (block->addr >> CT_PAGE_SHIFT); 144 pages = block->size >> CT_PAGE_SHIFT; 145 for (i = 0; i < pages; i++) { 146 unsigned long addr; 147 addr = snd_pcm_sgbuf_get_addr(substream, i << CT_PAGE_SHIFT); 148 ptp[pte_start + i] = addr; 149 } 150 151 block->size = size; 152 return block; 153} 154 155static void ct_vm_unmap(struct ct_vm *vm, struct ct_vm_block *block) 156{ 157 /* do unmapping */ 158 put_vm_block(vm, block); 159} 160 161/* * 162 * return the host physical addr of the @index-th device 163 * page table page on success, or ~0UL on failure. 164 * The first returned ~0UL indicates the termination. 165 * */ 166static dma_addr_t 167ct_get_ptp_phys(struct ct_vm *vm, int index) 168{ 169 dma_addr_t addr; 170 171 addr = (index >= CT_PTP_NUM) ? ~0UL : vm->ptp[index].addr; 172 173 return addr; 174} 175 176int ct_vm_create(struct ct_vm **rvm, struct pci_dev *pci) 177{ 178 struct ct_vm *vm; 179 struct ct_vm_block *block; 180 int i, err = 0; 181 182 *rvm = NULL; 183 184 vm = kzalloc(sizeof(*vm), GFP_KERNEL); 185 if (!vm) 186 return -ENOMEM; 187 188 mutex_init(&vm->lock); 189 190 /* Allocate page table pages */ 191 for (i = 0; i < CT_PTP_NUM; i++) { 192 err = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, 193 snd_dma_pci_data(pci), 194 PAGE_SIZE, &vm->ptp[i]); 195 if (err < 0) 196 break; 197 } 198 if (err < 0) { 199 /* no page table pages are allocated */ 200 ct_vm_destroy(vm); 201 return -ENOMEM; 202 } 203 vm->size = CT_ADDRS_PER_PAGE * i; 204 vm->map = ct_vm_map; 205 vm->unmap = ct_vm_unmap; 206 vm->get_ptp_phys = ct_get_ptp_phys; 207 INIT_LIST_HEAD(&vm->unused); 208 INIT_LIST_HEAD(&vm->used); 209 block = kzalloc(sizeof(*block), GFP_KERNEL); 210 if (NULL != block) { 211 block->addr = 0; 212 block->size = vm->size; 213 list_add(&block->list, &vm->unused); 214 } 215 216 *rvm = vm; 217 return 0; 218} 219 220/* The caller must ensure no mapping pages are being used 221 * by hardware before calling this function */ 222void ct_vm_destroy(struct ct_vm *vm) 223{ 224 int i; 225 struct list_head *pos; 226 struct ct_vm_block *entry; 227 228 /* free used and unused list nodes */ 229 while (!list_empty(&vm->used)) { 230 pos = vm->used.next; 231 list_del(pos); 232 entry = list_entry(pos, struct ct_vm_block, list); 233 kfree(entry); 234 } 235 while (!list_empty(&vm->unused)) { 236 pos = vm->unused.next; 237 list_del(pos); 238 entry = list_entry(pos, struct ct_vm_block, list); 239 kfree(entry); 240 } 241 242 /* free allocated page table pages */ 243 for (i = 0; i < CT_PTP_NUM; i++) 244 snd_dma_free_pages(&vm->ptp[i]); 245 246 vm->size = 0; 247 248 kfree(vm); 249} 250