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- /*
- * 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;
- }
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