From patchwork Fri May 7 00:02:32 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ralph Campbell X-Patchwork-Id: 97546 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by demeter.kernel.org (8.14.3/8.14.3) with ESMTP id o470UFms016682 for ; Fri, 7 May 2010 00:31:46 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752835Ab0EGACd (ORCPT ); Thu, 6 May 2010 20:02:33 -0400 Received: from vpn.pathscale.com ([198.186.3.75]:51956 "HELO mx.mv.qlogic.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with SMTP id S1752305Ab0EGACc (ORCPT ); Thu, 6 May 2010 20:02:32 -0400 Received: from chromite.mv.qlogic.com (chromite.mv.qlogic.com [10.29.2.82]) by mx.mv.qlogic.com (Postfix) with ESMTP id 9C5F1949C01A; Thu, 6 May 2010 17:02:32 -0700 (PDT) Received: from chromite.mv.qlogic.com (localhost.localdomain [127.0.0.1]) by chromite.mv.qlogic.com (Postfix) with ESMTP id 9C6EB142961; Thu, 6 May 2010 17:02:32 -0700 (PDT) From: Ralph Campbell Subject: [PATCH v3 42/52] IB/qib: Add qib_user_pages.c To: Roland Dreier Cc: linux-rdma@vger.kernel.org Date: Thu, 06 May 2010 17:02:32 -0700 Message-ID: <20100507000232.3441.59249.stgit@chromite.mv.qlogic.com> In-Reply-To: <20100506235849.3441.85930.stgit@chromite.mv.qlogic.com> References: <20100506235849.3441.85930.stgit@chromite.mv.qlogic.com> User-Agent: StGIT/0.14.3 MIME-Version: 1.0 Sender: linux-rdma-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org X-Greylist: IP, sender and recipient auto-whitelisted, not delayed by milter-greylist-4.2.3 (demeter.kernel.org [140.211.167.41]); Fri, 07 May 2010 00:31:48 +0000 (UTC) diff --git a/drivers/infiniband/hw/qib/qib_user_pages.c b/drivers/infiniband/hw/qib/qib_user_pages.c new file mode 100644 index 0000000..d7a26c1 --- /dev/null +++ b/drivers/infiniband/hw/qib/qib_user_pages.c @@ -0,0 +1,157 @@ +/* + * Copyright (c) 2006, 2007, 2008, 2009 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 +#include + +#include "qib.h" + +static void __qib_release_user_pages(struct page **p, size_t num_pages, + int dirty) +{ + size_t i; + + for (i = 0; i < num_pages; i++) { + if (dirty) + set_page_dirty_lock(p[i]); + put_page(p[i]); + } +} + +/* + * Call with current->mm->mmap_sem held. + */ +static int __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 && !capable(CAP_IPC_LOCK)) { + ret = -ENOMEM; + goto bail; + } + + 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->locked_vm += num_pages; + + ret = 0; + goto bail; + +bail_release: + __qib_release_user_pages(p, got, 0); +bail: + return ret; +} + +/** + * qib_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 qib_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; +} + +/** + * qib_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 qib_get_user_pages(unsigned long start_page, size_t num_pages, + struct page **p) +{ + int ret; + + down_write(¤t->mm->mmap_sem); + + ret = __get_user_pages(start_page, num_pages, p, NULL); + + up_write(¤t->mm->mmap_sem); + + return ret; +} + +void qib_release_user_pages(struct page **p, size_t num_pages) +{ + if (current->mm) /* during close after signal, mm can be NULL */ + down_write(¤t->mm->mmap_sem); + + __qib_release_user_pages(p, num_pages, 1); + + if (current->mm) { + current->mm->locked_vm -= num_pages; + up_write(¤t->mm->mmap_sem); + } +}