1/* 2 * SPU local store allocation routines 3 * 4 * Copyright 2007 Benjamin Herrenschmidt, IBM Corp. 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation; either version 2, or (at your option) 9 * any later version. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program; if not, write to the Free Software 18 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 19 */ 20 21#undef DEBUG 22 23#include <linux/kernel.h> 24#include <linux/mm.h> 25#include <linux/slab.h> 26#include <linux/vmalloc.h> 27 28#include <asm/spu.h> 29#include <asm/spu_csa.h> 30#include <asm/mmu.h> 31 32#include "spufs.h" 33 34static int spu_alloc_lscsa_std(struct spu_state *csa) 35{ 36 struct spu_lscsa *lscsa; 37 unsigned char *p; 38 39 lscsa = vmalloc(sizeof(struct spu_lscsa)); 40 if (!lscsa) 41 return -ENOMEM; 42 memset(lscsa, 0, sizeof(struct spu_lscsa)); 43 csa->lscsa = lscsa; 44 45 /* Set LS pages reserved to allow for user-space mapping. */ 46 for (p = lscsa->ls; p < lscsa->ls + LS_SIZE; p += PAGE_SIZE) 47 SetPageReserved(vmalloc_to_page(p)); 48 49 return 0; 50} 51 52static void spu_free_lscsa_std(struct spu_state *csa) 53{ 54 /* Clear reserved bit before vfree. */ 55 unsigned char *p; 56 57 if (csa->lscsa == NULL) 58 return; 59 60 for (p = csa->lscsa->ls; p < csa->lscsa->ls + LS_SIZE; p += PAGE_SIZE) 61 ClearPageReserved(vmalloc_to_page(p)); 62 63 vfree(csa->lscsa); 64} 65 66#ifdef CONFIG_SPU_FS_64K_LS 67 68#define SPU_64K_PAGE_SHIFT 16 69#define SPU_64K_PAGE_ORDER (SPU_64K_PAGE_SHIFT - PAGE_SHIFT) 70#define SPU_64K_PAGE_COUNT (1ul << SPU_64K_PAGE_ORDER) 71 72int spu_alloc_lscsa(struct spu_state *csa) 73{ 74 struct page **pgarray; 75 unsigned char *p; 76 int i, j, n_4k; 77 78 /* Check availability of 64K pages */ 79 if (!spu_64k_pages_available()) 80 goto fail; 81 82 csa->use_big_pages = 1; 83 84 pr_debug("spu_alloc_lscsa(csa=0x%p), trying to allocate 64K pages\n", 85 csa); 86 87 /* First try to allocate our 64K pages. We need 5 of them 88 * with the current implementation. In the future, we should try 89 * to separate the lscsa with the actual local store image, thus 90 * allowing us to require only 4 64K pages per context 91 */ 92 for (i = 0; i < SPU_LSCSA_NUM_BIG_PAGES; i++) { 93 csa->lscsa_pages[i] = alloc_pages(GFP_KERNEL, 94 SPU_64K_PAGE_ORDER); 95 if (csa->lscsa_pages[i] == NULL) 96 goto fail; 97 } 98 99 pr_debug(" success ! creating vmap...\n"); 100 101 /* Now we need to create a vmalloc mapping of these for the kernel 102 * and SPU context switch code to use. Currently, we stick to a 103 * normal kernel vmalloc mapping, which in our case will be 4K 104 */ 105 n_4k = SPU_64K_PAGE_COUNT * SPU_LSCSA_NUM_BIG_PAGES; 106 pgarray = kmalloc(sizeof(struct page *) * n_4k, GFP_KERNEL); 107 if (pgarray == NULL) 108 goto fail; 109 for (i = 0; i < SPU_LSCSA_NUM_BIG_PAGES; i++) 110 for (j = 0; j < SPU_64K_PAGE_COUNT; j++) 111 /* We assume all the struct page's are contiguous 112 * which should be hopefully the case for an order 4 113 * allocation.. 114 */ 115 pgarray[i * SPU_64K_PAGE_COUNT + j] = 116 csa->lscsa_pages[i] + j; 117 csa->lscsa = vmap(pgarray, n_4k, VM_USERMAP, PAGE_KERNEL); 118 kfree(pgarray); 119 if (csa->lscsa == NULL) 120 goto fail; 121 122 memset(csa->lscsa, 0, sizeof(struct spu_lscsa)); 123 124 for (p = csa->lscsa->ls; p < csa->lscsa->ls + LS_SIZE; p += PAGE_SIZE) 125 SetPageReserved(vmalloc_to_page(p)); 126 127 pr_debug(" all good !\n"); 128 129 return 0; 130fail: 131 pr_debug("spufs: failed to allocate lscsa 64K pages, falling back\n"); 132 spu_free_lscsa(csa); 133 return spu_alloc_lscsa_std(csa); 134} 135 136void spu_free_lscsa(struct spu_state *csa) 137{ 138 unsigned char *p; 139 int i; 140 141 if (!csa->use_big_pages) { 142 spu_free_lscsa_std(csa); 143 return; 144 } 145 csa->use_big_pages = 0; 146 147 if (csa->lscsa == NULL) 148 goto free_pages; 149 150 for (p = csa->lscsa->ls; p < csa->lscsa->ls + LS_SIZE; p += PAGE_SIZE) 151 ClearPageReserved(vmalloc_to_page(p)); 152 153 vunmap(csa->lscsa); 154 csa->lscsa = NULL; 155 156 free_pages: 157 158 for (i = 0; i < SPU_LSCSA_NUM_BIG_PAGES; i++) 159 if (csa->lscsa_pages[i]) 160 __free_pages(csa->lscsa_pages[i], SPU_64K_PAGE_ORDER); 161} 162 163#else /* CONFIG_SPU_FS_64K_LS */ 164 165int spu_alloc_lscsa(struct spu_state *csa) 166{ 167 return spu_alloc_lscsa_std(csa); 168} 169 170void spu_free_lscsa(struct spu_state *csa) 171{ 172 spu_free_lscsa_std(csa); 173} 174 175#endif /* !defined(CONFIG_SPU_FS_64K_LS) */ 176