/* * Copyright (c) 2006, 2007 QLogic Corporation. All rights reserved. * Copyright (c) 2003, 2004, 2005, 2006 PathScale, Inc. All rights reserved. * * This software is available to you under a choice of one of two * licenses. You may choose to be licensed under the terms of the GNU * General Public License (GPL) Version 2, available from the file * COPYING in the main directory of this source tree, or the * OpenIB.org BSD license below: * * Redistribution and use in source and binary forms, with or * without modification, are permitted provided that the following * conditions are met: * * - Redistributions of source code must retain the above * copyright notice, this list of conditions and the following * disclaimer. * * - Redistributions in binary form must reproduce the above * copyright notice, this list of conditions and the following * disclaimer in the documentation and/or other materials * provided with the distribution. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE * SOFTWARE. */ #include <linux/mm.h> #include <linux/device.h> #include <linux/slab.h> #include <linux/sched.h> #include "ipath_kernel.h" static void __ipath_release_user_pages(struct page **p, size_t num_pages, int dirty) { size_t i; for (i = 0; i < num_pages; i++) { ipath_cdbg(MM, "%lu/%lu put_page %p\n", (unsigned long) i, (unsigned long) num_pages, p[i]); if (dirty) set_page_dirty_lock(p[i]); put_page(p[i]); } } /* call with current->mm->mmap_sem held */ static int __ipath_get_user_pages(unsigned long start_page, size_t num_pages, struct page **p, struct vm_area_struct **vma) { unsigned long lock_limit; size_t got; int ret; lock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; if (num_pages > lock_limit) { ret = -ENOMEM; goto bail; } ipath_cdbg(VERBOSE, "pin %lx pages from vaddr %lx\n", (unsigned long) num_pages, start_page); for (got = 0; got < num_pages; got += ret) { ret = get_user_pages(current, current->mm, start_page + got * PAGE_SIZE, num_pages - got, 1, 1, p + got, vma); if (ret < 0) goto bail_release; } current->mm->pinned_vm += num_pages; ret = 0; goto bail; bail_release: __ipath_release_user_pages(p, got, 0); bail: return ret; } /** * ipath_map_page - a safety wrapper around pci_map_page() * * A dma_addr of all 0's is interpreted by the chip as "disabled". * Unfortunately, it can also be a valid dma_addr returned on some * architectures. * * The powerpc iommu assigns dma_addrs in ascending order, so we don't * have to bother with retries or mapping a dummy page to insure we * don't just get the same mapping again. * * I'm sure we won't be so lucky with other iommu's, so FIXME. */ dma_addr_t ipath_map_page(struct pci_dev *hwdev, struct page *page, unsigned long offset, size_t size, int direction) { dma_addr_t phys; phys = pci_map_page(hwdev, page, offset, size, direction); if (phys == 0) { pci_unmap_page(hwdev, phys, size, direction); phys = pci_map_page(hwdev, page, offset, size, direction); /* * FIXME: If we get 0 again, we should keep this page, * map another, then free the 0 page. */ } return phys; } /** * ipath_map_single - a safety wrapper around pci_map_single() * * Same idea as ipath_map_page(). */ dma_addr_t ipath_map_single(struct pci_dev *hwdev, void *ptr, size_t size, int direction) { dma_addr_t phys; phys = pci_map_single(hwdev, ptr, size, direction); if (phys == 0) { pci_unmap_single(hwdev, phys, size, direction); phys = pci_map_single(hwdev, ptr, size, direction); /* * FIXME: If we get 0 again, we should keep this page, * map another, then free the 0 page. */ } return phys; } /** * ipath_get_user_pages - lock user pages into memory * @start_page: the start page * @num_pages: the number of pages * @p: the output page structures * * This function takes a given start page (page aligned user virtual * address) and pins it and the following specified number of pages. For * now, num_pages is always 1, but that will probably change at some point * (because caller is doing expected sends on a single virtually contiguous * buffer, so we can do all pages at once). */ int ipath_get_user_pages(unsigned long start_page, size_t num_pages, struct page **p) { int ret; down_write(¤t->mm->mmap_sem); ret = __ipath_get_user_pages(start_page, num_pages, p, NULL); up_write(¤t->mm->mmap_sem); return ret; } void ipath_release_user_pages(struct page **p, size_t num_pages) { down_write(¤t->mm->mmap_sem); __ipath_release_user_pages(p, num_pages, 1); current->mm->pinned_vm -= num_pages; up_write(¤t->mm->mmap_sem); } struct ipath_user_pages_work { struct work_struct work; struct mm_struct *mm; unsigned long num_pages; }; static void user_pages_account(struct work_struct *_work) { struct ipath_user_pages_work *work = container_of(_work, struct ipath_user_pages_work, work); down_write(&work->mm->mmap_sem); work->mm->pinned_vm -= work->num_pages; up_write(&work->mm->mmap_sem); mmput(work->mm); kfree(work); } void ipath_release_user_pages_on_close(struct page **p, size_t num_pages) { struct ipath_user_pages_work *work; struct mm_struct *mm; __ipath_release_user_pages(p, num_pages, 1); mm = get_task_mm(current); if (!mm) return; work = kmalloc(sizeof(*work), GFP_KERNEL); if (!work) goto bail_mm; INIT_WORK(&work->work, user_pages_account); work->mm = mm; work->num_pages = num_pages; queue_work(ib_wq, &work->work); return; bail_mm: mmput(mm); return; }