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Diffstat (limited to '')
| -rw-r--r-- | drivers/infiniband/hw/hfi1/user_pages.c | 137 |
1 files changed, 137 insertions, 0 deletions
diff --git a/drivers/infiniband/hw/hfi1/user_pages.c b/drivers/infiniband/hw/hfi1/user_pages.c new file mode 100644 index 000000000..e341e6dcc --- /dev/null +++ b/drivers/infiniband/hw/hfi1/user_pages.c @@ -0,0 +1,137 @@ +/* + * Copyright(c) 2015-2017 Intel Corporation. + * + * This file is provided under a dual BSD/GPLv2 license. When using or + * redistributing this file, you may do so under either license. + * + * GPL LICENSE SUMMARY + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of version 2 of the GNU General Public License as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * BSD LICENSE + * + * 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. + * - Neither the name of Intel Corporation nor the names of its + * contributors may be used to endorse or promote products derived + * from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + */ + +#include <linux/mm.h> +#include <linux/sched/signal.h> +#include <linux/device.h> +#include <linux/module.h> + +#include "hfi.h" + +static unsigned long cache_size = 256; +module_param(cache_size, ulong, S_IRUGO | S_IWUSR); +MODULE_PARM_DESC(cache_size, "Send and receive side cache size limit (in MB)"); + +/* + * Determine whether the caller can pin pages. + * + * This function should be used in the implementation of buffer caches. + * The cache implementation should call this function prior to attempting + * to pin buffer pages in order to determine whether they should do so. + * The function computes cache limits based on the configured ulimit and + * cache size. Use of this function is especially important for caches + * which are not limited in any other way (e.g. by HW resources) and, thus, + * could keeping caching buffers. + * + */ +bool hfi1_can_pin_pages(struct hfi1_devdata *dd, struct mm_struct *mm, + u32 nlocked, u32 npages) +{ + unsigned long ulimit = rlimit(RLIMIT_MEMLOCK), pinned, cache_limit, + size = (cache_size * (1UL << 20)); /* convert to bytes */ + unsigned int usr_ctxts = + dd->num_rcv_contexts - dd->first_dyn_alloc_ctxt; + bool can_lock = capable(CAP_IPC_LOCK); + + /* + * Calculate per-cache size. The calculation below uses only a quarter + * of the available per-context limit. This leaves space for other + * pinning. Should we worry about shared ctxts? + */ + cache_limit = (ulimit / usr_ctxts) / 4; + + /* If ulimit isn't set to "unlimited" and is smaller than cache_size. */ + if (ulimit != (-1UL) && size > cache_limit) + size = cache_limit; + + /* Convert to number of pages */ + size = DIV_ROUND_UP(size, PAGE_SIZE); + + down_read(&mm->mmap_sem); + pinned = mm->pinned_vm; + up_read(&mm->mmap_sem); + + /* First, check the absolute limit against all pinned pages. */ + if (pinned + npages >= ulimit && !can_lock) + return false; + + return ((nlocked + npages) <= size) || can_lock; +} + +int hfi1_acquire_user_pages(struct mm_struct *mm, unsigned long vaddr, size_t npages, + bool writable, struct page **pages) +{ + int ret; + + ret = get_user_pages_fast(vaddr, npages, writable, pages); + if (ret < 0) + return ret; + + down_write(&mm->mmap_sem); + mm->pinned_vm += ret; + up_write(&mm->mmap_sem); + + return ret; +} + +void hfi1_release_user_pages(struct mm_struct *mm, struct page **p, + size_t npages, bool dirty) +{ + size_t i; + + for (i = 0; i < npages; i++) { + if (dirty) + set_page_dirty_lock(p[i]); + put_page(p[i]); + } + + if (mm) { /* during close after signal, mm can be NULL */ + down_write(&mm->mmap_sem); + mm->pinned_vm -= npages; + up_write(&mm->mmap_sem); + } +} |