diff options
| -rw-r--r-- | drivers/infiniband/core/uverbs_mem.c | 221 |
1 files changed, 221 insertions, 0 deletions
diff --git a/drivers/infiniband/core/uverbs_mem.c b/drivers/infiniband/core/uverbs_mem.c new file mode 100644 index 00000000000..ed550f6595b --- /dev/null +++ b/drivers/infiniband/core/uverbs_mem.c @@ -0,0 +1,221 @@ +/* + * Copyright (c) 2005 Topspin Communications. All rights reserved. + * Copyright (c) 2005 Cisco Systems. 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. + * + * $Id: uverbs_mem.c 2743 2005-06-28 22:27:59Z roland $ + */ + +#include <linux/mm.h> +#include <linux/dma-mapping.h> + +#include "uverbs.h" + +struct ib_umem_account_work { + struct work_struct work; + struct mm_struct *mm; + unsigned long diff; +}; + + +static void __ib_umem_release(struct ib_device *dev, struct ib_umem *umem, int dirty) +{ + struct ib_umem_chunk *chunk, *tmp; + int i; + + list_for_each_entry_safe(chunk, tmp, &umem->chunk_list, list) { + dma_unmap_sg(dev->dma_device, chunk->page_list, + chunk->nents, DMA_BIDIRECTIONAL); + for (i = 0; i < chunk->nents; ++i) { + if (umem->writable && dirty) + set_page_dirty_lock(chunk->page_list[i].page); + put_page(chunk->page_list[i].page); + } + + kfree(chunk); + } +} + +int ib_umem_get(struct ib_device *dev, struct ib_umem *mem, + void *addr, size_t size, int write) +{ + struct page **page_list; + struct ib_umem_chunk *chunk; + unsigned long locked; + unsigned long lock_limit; + unsigned long cur_base; + unsigned long npages; + int ret = 0; + int off; + int i; + + if (!can_do_mlock()) + return -EPERM; + + page_list = (struct page **) __get_free_page(GFP_KERNEL); + if (!page_list) + return -ENOMEM; + + mem->user_base = (unsigned long) addr; + mem->length = size; + mem->offset = (unsigned long) addr & ~PAGE_MASK; + mem->page_size = PAGE_SIZE; + mem->writable = write; + + INIT_LIST_HEAD(&mem->chunk_list); + + npages = PAGE_ALIGN(size + mem->offset) >> PAGE_SHIFT; + + down_write(¤t->mm->mmap_sem); + + locked = npages + current->mm->locked_vm; + lock_limit = current->signal->rlim[RLIMIT_MEMLOCK].rlim_cur >> PAGE_SHIFT; + + if ((locked > lock_limit) && !capable(CAP_IPC_LOCK)) { + ret = -ENOMEM; + goto out; + } + + cur_base = (unsigned long) addr & PAGE_MASK; + + while (npages) { + ret = get_user_pages(current, current->mm, cur_base, + min_t(int, npages, + PAGE_SIZE / sizeof (struct page *)), + 1, !write, page_list, NULL); + + if (ret < 0) + goto out; + + cur_base += ret * PAGE_SIZE; + npages -= ret; + + off = 0; + + while (ret) { + chunk = kmalloc(sizeof *chunk + sizeof (struct scatterlist) * + min_t(int, ret, IB_UMEM_MAX_PAGE_CHUNK), + GFP_KERNEL); + if (!chunk) { + ret = -ENOMEM; + goto out; + } + + chunk->nents = min_t(int, ret, IB_UMEM_MAX_PAGE_CHUNK); + for (i = 0; i < chunk->nents; ++i) { + chunk->page_list[i].page = page_list[i + off]; + chunk->page_list[i].offset = 0; + chunk->page_list[i].length = PAGE_SIZE; + } + + chunk->nmap = dma_map_sg(dev->dma_device, + &chunk->page_list[0], + chunk->nents, + DMA_BIDIRECTIONAL); + if (chunk->nmap <= 0) { + for (i = 0; i < chunk->nents; ++i) + put_page(chunk->page_list[i].page); + kfree(chunk); + + ret = -ENOMEM; + goto out; + } + + ret -= chunk->nents; + off += chunk->nents; + list_add_tail(&chunk->list, &mem->chunk_list); + } + + ret = 0; + } + +out: + if (ret < 0) + __ib_umem_release(dev, mem, 0); + else + current->mm->locked_vm = locked; + + up_write(¤t->mm->mmap_sem); + free_page((unsigned long) page_list); + + return ret; +} + +void ib_umem_release(struct ib_device *dev, struct ib_umem *umem) +{ + __ib_umem_release(dev, umem, 1); + + down_write(¤t->mm->mmap_sem); + current->mm->locked_vm -= + PAGE_ALIGN(umem->length + umem->offset) >> PAGE_SHIFT; + up_write(¤t->mm->mmap_sem); +} + +static void ib_umem_account(void *work_ptr) +{ + struct ib_umem_account_work *work = work_ptr; + + down_write(&work->mm->mmap_sem); + work->mm->locked_vm -= work->diff; + up_write(&work->mm->mmap_sem); + mmput(work->mm); + kfree(work); +} + +void ib_umem_release_on_close(struct ib_device *dev, struct ib_umem *umem) +{ + struct ib_umem_account_work *work; + struct mm_struct *mm; + + __ib_umem_release(dev, umem, 1); + + mm = get_task_mm(current); + if (!mm) + return; + + /* + * We may be called with the mm's mmap_sem already held. This + * can happen when a userspace munmap() is the call that drops + * the last reference to our file and calls our release + * method. If there are memory regions to destroy, we'll end + * up here and not be able to take the mmap_sem. Therefore we + * defer the vm_locked accounting to the system workqueue. + */ + + work = kmalloc(sizeof *work, GFP_KERNEL); + if (!work) + return; + + INIT_WORK(&work->work, ib_umem_account, work); + work->mm = mm; + work->diff = PAGE_ALIGN(umem->length + umem->offset) >> PAGE_SHIFT; + + schedule_work(&work->work); +} |