1/* 2 * Copyright (c) 2006, 2007 QLogic Corporation. All rights reserved. 3 * Copyright (c) 2003, 2004, 2005, 2006 PathScale, Inc. All rights reserved. 4 * 5 * This software is available to you under a choice of one of two 6 * licenses. You may choose to be licensed under the terms of the GNU 7 * General Public License (GPL) Version 2, available from the file 8 * COPYING in the main directory of this source tree, or the 9 * OpenIB.org BSD license below: 10 * 11 * Redistribution and use in source and binary forms, with or 12 * without modification, are permitted provided that the following 13 * conditions are met: 14 * 15 * - Redistributions of source code must retain the above 16 * copyright notice, this list of conditions and the following 17 * disclaimer. 18 * 19 * - Redistributions in binary form must reproduce the above 20 * copyright notice, this list of conditions and the following 21 * disclaimer in the documentation and/or other materials 22 * provided with the distribution. 23 * 24 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 25 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 26 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 27 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS 28 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN 29 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN 30 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 31 * SOFTWARE. 32 */ 33 34#include <linux/mm.h> 35#include <linux/device.h> 36#include <linux/slab.h> 37#include <linux/sched.h> 38 39#include "ipath_kernel.h" 40 41static void __ipath_release_user_pages(struct page **p, size_t num_pages, 42 int dirty) 43{ 44 size_t i; 45 46 for (i = 0; i < num_pages; i++) { 47 ipath_cdbg(MM, "%lu/%lu put_page %p\n", (unsigned long) i, 48 (unsigned long) num_pages, p[i]); 49 if (dirty) 50 set_page_dirty_lock(p[i]); 51 put_page(p[i]); 52 } 53} 54 55/* call with current->mm->mmap_sem held */ 56static int __get_user_pages(unsigned long start_page, size_t num_pages, 57 struct page **p, struct vm_area_struct **vma) 58{ 59 unsigned long lock_limit; 60 size_t got; 61 int ret; 62 63 lock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; 64 65 if (num_pages > lock_limit) { 66 ret = -ENOMEM; 67 goto bail; 68 } 69 70 ipath_cdbg(VERBOSE, "pin %lx pages from vaddr %lx\n", 71 (unsigned long) num_pages, start_page); 72 73 for (got = 0; got < num_pages; got += ret) { 74 ret = get_user_pages(current, current->mm, 75 start_page + got * PAGE_SIZE, 76 num_pages - got, 1, 1, 77 p + got, vma); 78 if (ret < 0) 79 goto bail_release; 80 } 81 82 current->mm->locked_vm += num_pages; 83 84 ret = 0; 85 goto bail; 86 87bail_release: 88 __ipath_release_user_pages(p, got, 0); 89bail: 90 return ret; 91} 92 93dma_addr_t ipath_map_page(struct pci_dev *hwdev, struct page *page, 94 unsigned long offset, size_t size, int direction) 95{ 96 dma_addr_t phys; 97 98 phys = pci_map_page(hwdev, page, offset, size, direction); 99 100 if (phys == 0) { 101 pci_unmap_page(hwdev, phys, size, direction); 102 phys = pci_map_page(hwdev, page, offset, size, direction); 103 } 104 105 return phys; 106} 107 108/** 109 * ipath_map_single - a safety wrapper around pci_map_single() 110 * 111 * Same idea as ipath_map_page(). 112 */ 113dma_addr_t ipath_map_single(struct pci_dev *hwdev, void *ptr, size_t size, 114 int direction) 115{ 116 dma_addr_t phys; 117 118 phys = pci_map_single(hwdev, ptr, size, direction); 119 120 if (phys == 0) { 121 pci_unmap_single(hwdev, phys, size, direction); 122 phys = pci_map_single(hwdev, ptr, size, direction); 123 } 124 125 return phys; 126} 127 128/** 129 * ipath_get_user_pages - lock user pages into memory 130 * @start_page: the start page 131 * @num_pages: the number of pages 132 * @p: the output page structures 133 * 134 * This function takes a given start page (page aligned user virtual 135 * address) and pins it and the following specified number of pages. For 136 * now, num_pages is always 1, but that will probably change at some point 137 * (because caller is doing expected sends on a single virtually contiguous 138 * buffer, so we can do all pages at once). 139 */ 140int ipath_get_user_pages(unsigned long start_page, size_t num_pages, 141 struct page **p) 142{ 143 int ret; 144 145 down_write(¤t->mm->mmap_sem); 146 147 ret = __get_user_pages(start_page, num_pages, p, NULL); 148 149 up_write(¤t->mm->mmap_sem); 150 151 return ret; 152} 153 154void ipath_release_user_pages(struct page **p, size_t num_pages) 155{ 156 down_write(¤t->mm->mmap_sem); 157 158 __ipath_release_user_pages(p, num_pages, 1); 159 160 current->mm->locked_vm -= num_pages; 161 162 up_write(¤t->mm->mmap_sem); 163} 164 165struct ipath_user_pages_work { 166 struct work_struct work; 167 struct mm_struct *mm; 168 unsigned long num_pages; 169}; 170 171static void user_pages_account(struct work_struct *_work) 172{ 173 struct ipath_user_pages_work *work = 174 container_of(_work, struct ipath_user_pages_work, work); 175 176 down_write(&work->mm->mmap_sem); 177 work->mm->locked_vm -= work->num_pages; 178 up_write(&work->mm->mmap_sem); 179 mmput(work->mm); 180 kfree(work); 181} 182 183void ipath_release_user_pages_on_close(struct page **p, size_t num_pages) 184{ 185 struct ipath_user_pages_work *work; 186 struct mm_struct *mm; 187 188 __ipath_release_user_pages(p, num_pages, 1); 189 190 mm = get_task_mm(current); 191 if (!mm) 192 return; 193 194 work = kmalloc(sizeof(*work), GFP_KERNEL); 195 if (!work) 196 goto bail_mm; 197 198 INIT_WORK(&work->work, user_pages_account); 199 work->mm = mm; 200 work->num_pages = num_pages; 201 202 schedule_work(&work->work); 203 return; 204 205bail_mm: 206 mmput(mm); 207 return; 208} 209