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Release 4.7 drivers/infiniband/hw/usnic/usnic_uiom.c

/*
 * Copyright (c) 2005 Topspin Communications.  All rights reserved.
 * Copyright (c) 2005 Mellanox Technologies. All rights reserved.
 * Copyright (c) 2013 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
 * 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/dma-mapping.h>
#include <linux/sched.h>
#include <linux/hugetlb.h>
#include <linux/iommu.h>
#include <linux/workqueue.h>
#include <linux/list.h>
#include <linux/pci.h>

#include "usnic_log.h"
#include "usnic_uiom.h"
#include "usnic_uiom_interval_tree.h"


static struct workqueue_struct *usnic_uiom_wq;


#define USNIC_UIOM_PAGE_CHUNK						\
	((PAGE_SIZE - offsetof(struct usnic_uiom_chunk, page_list))     /\
        ((void *) &((struct usnic_uiom_chunk *) 0)->page_list[1] -      \
        (void *) &((struct usnic_uiom_chunk *) 0)->page_list[0]))


static void usnic_uiom_reg_account(struct work_struct *work) { struct usnic_uiom_reg *umem = container_of(work, struct usnic_uiom_reg, work); down_write(&umem->mm->mmap_sem); umem->mm->locked_vm -= umem->diff; up_write(&umem->mm->mmap_sem); mmput(umem->mm); kfree(umem); }

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static int usnic_uiom_dma_fault(struct iommu_domain *domain, struct device *dev, unsigned long iova, int flags, void *token) { usnic_err("Device %s iommu fault domain 0x%pK va 0x%lx flags 0x%x\n", dev_name(dev), domain, iova, flags); return -ENOSYS; }

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static void usnic_uiom_put_pages(struct list_head *chunk_list, int dirty) { struct usnic_uiom_chunk *chunk, *tmp; struct page *page; struct scatterlist *sg; int i; dma_addr_t pa; list_for_each_entry_safe(chunk, tmp, chunk_list, list) { for_each_sg(chunk->page_list, sg, chunk->nents, i) { page = sg_page(sg); pa = sg_phys(sg); if (dirty) set_page_dirty_lock(page); put_page(page); usnic_dbg("pa: %pa\n", &pa); } kfree(chunk); } }

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static int usnic_uiom_get_pages(unsigned long addr, size_t size, int writable, int dmasync, struct list_head *chunk_list) { struct page **page_list; struct scatterlist *sg; struct usnic_uiom_chunk *chunk; unsigned long locked; unsigned long lock_limit; unsigned long cur_base; unsigned long npages; int ret; int off; int i; int flags; dma_addr_t pa; if (!can_do_mlock()) return -EPERM; INIT_LIST_HEAD(chunk_list); page_list = (struct page **) __get_free_page(GFP_KERNEL); if (!page_list) return -ENOMEM; npages = PAGE_ALIGN(size + (addr & ~PAGE_MASK)) >> PAGE_SHIFT; down_write(&current->mm->mmap_sem); locked = npages + current->mm->locked_vm; lock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; if ((locked > lock_limit) && !capable(CAP_IPC_LOCK)) { ret = -ENOMEM; goto out; } flags = IOMMU_READ | IOMMU_CACHE; flags |= (writable) ? IOMMU_WRITE : 0; cur_base = addr & PAGE_MASK; ret = 0; while (npages) { ret = get_user_pages(cur_base, min_t(unsigned long, npages, PAGE_SIZE / sizeof(struct page *)), 1, !writable, page_list, NULL); if (ret < 0) goto out; npages -= ret; off = 0; while (ret) { chunk = kmalloc(sizeof(*chunk) + sizeof(struct scatterlist) * min_t(int, ret, USNIC_UIOM_PAGE_CHUNK), GFP_KERNEL); if (!chunk) { ret = -ENOMEM; goto out; } chunk->nents = min_t(int, ret, USNIC_UIOM_PAGE_CHUNK); sg_init_table(chunk->page_list, chunk->nents); for_each_sg(chunk->page_list, sg, chunk->nents, i) { sg_set_page(sg, page_list[i + off], PAGE_SIZE, 0); pa = sg_phys(sg); usnic_dbg("va: 0x%lx pa: %pa\n", cur_base + i*PAGE_SIZE, &pa); } cur_base += chunk->nents * PAGE_SIZE; ret -= chunk->nents; off += chunk->nents; list_add_tail(&chunk->list, chunk_list); } ret = 0; } out: if (ret < 0) usnic_uiom_put_pages(chunk_list, 0); else current->mm->locked_vm = locked; up_write(&current->mm->mmap_sem); free_page((unsigned long) page_list); return ret; }

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static void usnic_uiom_unmap_sorted_intervals(struct list_head *intervals, struct usnic_uiom_pd *pd) { struct usnic_uiom_interval_node *interval, *tmp; long unsigned va, size; list_for_each_entry_safe(interval, tmp, intervals, link) { va = interval->start << PAGE_SHIFT; size = ((interval->last - interval->start) + 1) << PAGE_SHIFT; while (size > 0) { /* Workaround for RH 970401 */ usnic_dbg("va 0x%lx size 0x%lx", va, PAGE_SIZE); iommu_unmap(pd->domain, va, PAGE_SIZE); va += PAGE_SIZE; size -= PAGE_SIZE; } } }

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static void __usnic_uiom_reg_release(struct usnic_uiom_pd *pd, struct usnic_uiom_reg *uiomr, int dirty) { int npages; unsigned long vpn_start, vpn_last; struct usnic_uiom_interval_node *interval, *tmp; int writable = 0; LIST_HEAD(rm_intervals); npages = PAGE_ALIGN(uiomr->length + uiomr->offset) >> PAGE_SHIFT; vpn_start = (uiomr->va & PAGE_MASK) >> PAGE_SHIFT; vpn_last = vpn_start + npages - 1; spin_lock(&pd->lock); usnic_uiom_remove_interval(&pd->rb_root, vpn_start, vpn_last, &rm_intervals); usnic_uiom_unmap_sorted_intervals(&rm_intervals, pd); list_for_each_entry_safe(interval, tmp, &rm_intervals, link) { if (interval->flags & IOMMU_WRITE) writable = 1; list_del(&interval->link); kfree(interval); } usnic_uiom_put_pages(&uiomr->chunk_list, dirty & writable); spin_unlock(&pd->lock); }

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static int usnic_uiom_map_sorted_intervals(struct list_head *intervals, struct usnic_uiom_reg *uiomr) { int i, err; size_t size; struct usnic_uiom_chunk *chunk; struct usnic_uiom_interval_node *interval_node; dma_addr_t pa; dma_addr_t pa_start = 0; dma_addr_t pa_end = 0; long int va_start = -EINVAL; struct usnic_uiom_pd *pd = uiomr->pd; long int va = uiomr->va & PAGE_MASK; int flags = IOMMU_READ | IOMMU_CACHE; flags |= (uiomr->writable) ? IOMMU_WRITE : 0; chunk = list_first_entry(&uiomr->chunk_list, struct usnic_uiom_chunk, list); list_for_each_entry(interval_node, intervals, link) { iter_chunk: for (i = 0; i < chunk->nents; i++, va += PAGE_SIZE) { pa = sg_phys(&chunk->page_list[i]); if ((va >> PAGE_SHIFT) < interval_node->start) continue; if ((va >> PAGE_SHIFT) == interval_node->start) { /* First page of the interval */ va_start = va; pa_start = pa; pa_end = pa; } WARN_ON(va_start == -EINVAL); if ((pa_end + PAGE_SIZE != pa) && (pa != pa_start)) { /* PAs are not contiguous */ size = pa_end - pa_start + PAGE_SIZE; usnic_dbg("va 0x%lx pa %pa size 0x%zx flags 0x%x", va_start, &pa_start, size, flags); err = iommu_map(pd->domain, va_start, pa_start, size, flags); if (err) { usnic_err("Failed to map va 0x%lx pa %pa size 0x%zx with err %d\n", va_start, &pa_start, size, err); goto err_out; } va_start = va; pa_start = pa; pa_end = pa; } if ((va >> PAGE_SHIFT) == interval_node->last) { /* Last page of the interval */ size = pa - pa_start + PAGE_SIZE; usnic_dbg("va 0x%lx pa %pa size 0x%zx flags 0x%x\n", va_start, &pa_start, size, flags); err = iommu_map(pd->domain, va_start, pa_start, size, flags); if (err) { usnic_err("Failed to map va 0x%lx pa %pa size 0x%zx with err %d\n", va_start, &pa_start, size, err); goto err_out; } break; } if (pa != pa_start) pa_end += PAGE_SIZE; } if (i == chunk->nents) { /* * Hit last entry of the chunk, * hence advance to next chunk */ chunk = list_first_entry(&chunk->list, struct usnic_uiom_chunk, list); goto iter_chunk; } } return 0; err_out: usnic_uiom_unmap_sorted_intervals(intervals, pd); return err; }

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struct usnic_uiom_reg *usnic_uiom_reg_get(struct usnic_uiom_pd *pd, unsigned long addr, size_t size, int writable, int dmasync) { struct usnic_uiom_reg *uiomr; unsigned long va_base, vpn_start, vpn_last; unsigned long npages; int offset, err; LIST_HEAD(sorted_diff_intervals); /* * Intel IOMMU map throws an error if a translation entry is * changed from read to write. This module may not unmap * and then remap the entry after fixing the permission * b/c this open up a small windows where hw DMA may page fault * Hence, make all entries to be writable. */ writable = 1; va_base = addr & PAGE_MASK; offset = addr & ~PAGE_MASK; npages = PAGE_ALIGN(size + offset) >> PAGE_SHIFT; vpn_start = (addr & PAGE_MASK) >> PAGE_SHIFT; vpn_last = vpn_start + npages - 1; uiomr = kmalloc(sizeof(*uiomr), GFP_KERNEL); if (!uiomr) return ERR_PTR(-ENOMEM); uiomr->va = va_base; uiomr->offset = offset; uiomr->length = size; uiomr->writable = writable; uiomr->pd = pd; err = usnic_uiom_get_pages(addr, size, writable, dmasync, &uiomr->chunk_list); if (err) { usnic_err("Failed get_pages vpn [0x%lx,0x%lx] err %d\n", vpn_start, vpn_last, err); goto out_free_uiomr; } spin_lock(&pd->lock); err = usnic_uiom_get_intervals_diff(vpn_start, vpn_last, (writable) ? IOMMU_WRITE : 0, IOMMU_WRITE, &pd->rb_root, &sorted_diff_intervals); if (err) { usnic_err("Failed disjoint interval vpn [0x%lx,0x%lx] err %d\n", vpn_start, vpn_last, err); goto out_put_pages; } err = usnic_uiom_map_sorted_intervals(&sorted_diff_intervals, uiomr); if (err) { usnic_err("Failed map interval vpn [0x%lx,0x%lx] err %d\n", vpn_start, vpn_last, err); goto out_put_intervals; } err = usnic_uiom_insert_interval(&pd->rb_root, vpn_start, vpn_last, (writable) ? IOMMU_WRITE : 0); if (err) { usnic_err("Failed insert interval vpn [0x%lx,0x%lx] err %d\n", vpn_start, vpn_last, err); goto out_unmap_intervals; } usnic_uiom_put_interval_set(&sorted_diff_intervals); spin_unlock(&pd->lock); return uiomr; out_unmap_intervals: usnic_uiom_unmap_sorted_intervals(&sorted_diff_intervals, pd); out_put_intervals: usnic_uiom_put_interval_set(&sorted_diff_intervals); out_put_pages: usnic_uiom_put_pages(&uiomr->chunk_list, 0); spin_unlock(&pd->lock); out_free_uiomr: kfree(uiomr); return ERR_PTR(err); }

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void usnic_uiom_reg_release(struct usnic_uiom_reg *uiomr, int closing) { struct mm_struct *mm; unsigned long diff; __usnic_uiom_reg_release(uiomr->pd, uiomr, 1); mm = get_task_mm(current); if (!mm) { kfree(uiomr); return; } diff = PAGE_ALIGN(uiomr->length + uiomr->offset) >> PAGE_SHIFT; /* * 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. In that case * we defer the vm_locked accounting to the system workqueue. */ if (closing) { if (!down_write_trylock(&mm->mmap_sem)) { INIT_WORK(&uiomr->work, usnic_uiom_reg_account); uiomr->mm = mm; uiomr->diff = diff; queue_work(usnic_uiom_wq, &uiomr->work); return; } } else down_write(&mm->mmap_sem); current->mm->locked_vm -= diff; up_write(&mm->mmap_sem); mmput(mm); kfree(uiomr); }

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struct usnic_uiom_pd *usnic_uiom_alloc_pd(void) { struct usnic_uiom_pd *pd; void *domain; pd = kzalloc(sizeof(*pd), GFP_KERNEL); if (!pd) return ERR_PTR(-ENOMEM); pd->domain = domain = iommu_domain_alloc(&pci_bus_type); if (!domain) { usnic_err("Failed to allocate IOMMU domain"); kfree(pd); return ERR_PTR(-ENOMEM); } iommu_set_fault_handler(pd->domain, usnic_uiom_dma_fault, NULL); spin_lock_init(&pd->lock); INIT_LIST_HEAD(&pd->devs); return pd; }

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void usnic_uiom_dealloc_pd(struct usnic_uiom_pd *pd) { iommu_domain_free(pd->domain); kfree(pd); }

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int usnic_uiom_attach_dev_to_pd(struct usnic_uiom_pd *pd, struct device *dev) { struct usnic_uiom_dev *uiom_dev; int err; uiom_dev = kzalloc(sizeof(*uiom_dev), GFP_ATOMIC); if (!uiom_dev) return -ENOMEM; uiom_dev->dev = dev; err = iommu_attach_device(pd->domain, dev); if (err) goto out_free_dev; if (!iommu_capable(dev->bus, IOMMU_CAP_CACHE_COHERENCY)) { usnic_err("IOMMU of %s does not support cache coherency\n", dev_name(dev)); err = -EINVAL; goto out_detach_device; } spin_lock(&pd->lock); list_add_tail(&uiom_dev->link, &pd->devs); pd->dev_cnt++; spin_unlock(&pd->lock); return 0; out_detach_device: iommu_detach_device(pd->domain, dev); out_free_dev: kfree(uiom_dev); return err; }

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Total159100.00%3100.00%


void usnic_uiom_detach_dev_from_pd(struct usnic_uiom_pd *pd, struct device *dev) { struct usnic_uiom_dev *uiom_dev; int found = 0; spin_lock(&pd->lock); list_for_each_entry(uiom_dev, &pd->devs, link) { if (uiom_dev->dev == dev) { found = 1; break; } } if (!found) { usnic_err("Unable to free dev %s - not found\n", dev_name(dev)); spin_unlock(&pd->lock); return; } list_del(&uiom_dev->link); pd->dev_cnt--; spin_unlock(&pd->lock); return iommu_detach_device(pd->domain, dev); }

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struct device **usnic_uiom_get_dev_list(struct usnic_uiom_pd *pd) { struct usnic_uiom_dev *uiom_dev; struct device **devs; int i = 0; spin_lock(&pd->lock); devs = kcalloc(pd->dev_cnt + 1, sizeof(*devs), GFP_ATOMIC); if (!devs) { devs = ERR_PTR(-ENOMEM); goto out; } list_for_each_entry(uiom_dev, &pd->devs, link) { devs[i++] = uiom_dev->dev; } out: spin_unlock(&pd->lock); return devs; }

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void usnic_uiom_free_dev_list(struct device **devs) { kfree(devs); }

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int usnic_uiom_init(char *drv_name) { if (!iommu_present(&pci_bus_type)) { usnic_err("IOMMU required but not present or enabled. USNIC QPs will not function w/o enabling IOMMU\n"); return -EPERM; } usnic_uiom_wq = create_workqueue(drv_name); if (!usnic_uiom_wq) { usnic_err("Unable to alloc wq for drv %s\n", drv_name); return -ENOMEM; } return 0; }

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void usnic_uiom_fini(void) { flush_workqueue(usnic_uiom_wq); destroy_workqueue(usnic_uiom_wq); }

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joerg roedeljoerg roedel30.12%114.29%
dan carpenterdan carpenter30.12%228.57%
fabio estevamfabio estevam10.04%114.29%
jeff squyresjeff squyres10.04%114.29%
Total2561100.00%7100.00%
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