diff options
Diffstat (limited to 'drivers/infiniband/hw/usnic/usnic_uiom.c')
-rw-r--r-- | drivers/infiniband/hw/usnic/usnic_uiom.c | 618 |
1 files changed, 618 insertions, 0 deletions
diff --git a/drivers/infiniband/hw/usnic/usnic_uiom.c b/drivers/infiniband/hw/usnic/usnic_uiom.c new file mode 100644 index 000000000..9dd39daa6 --- /dev/null +++ b/drivers/infiniband/hw/usnic/usnic_uiom.c @@ -0,0 +1,618 @@ +/* + * 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/signal.h> +#include <linux/sched/mm.h> +#include <linux/hugetlb.h> +#include <linux/iommu.h> +#include <linux/workqueue.h> +#include <linux/list.h> +#include <linux/pci.h> +#include <rdma/ib_verbs.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); +} + +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; +} + +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 (!PageDirty(page) && dirty) + set_page_dirty_lock(page); + put_page(page); + usnic_dbg("pa: %pa\n", &pa); + } + kfree(chunk); + } +} + +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; + unsigned int gup_flags; + + /* + * If the combination of the addr and size requested for this memory + * region causes an integer overflow, return error. + */ + if (((addr + size) < addr) || PAGE_ALIGN(addr + size) < (addr + size)) + return -EINVAL; + + if (!size) + return -EINVAL; + + 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(¤t->mm->mmap_sem); + + locked = npages + current->mm->pinned_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; + gup_flags = FOLL_WRITE; + gup_flags |= (writable) ? 0 : FOLL_FORCE; + cur_base = addr & PAGE_MASK; + ret = 0; + + while (npages) { + ret = get_user_pages_longterm(cur_base, + min_t(unsigned long, npages, + PAGE_SIZE / sizeof(struct page *)), + gup_flags, 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->pinned_vm = locked; + + up_write(¤t->mm->mmap_sem); + free_page((unsigned long) page_list); + return ret; +} + +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; + } + } +} + +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->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); +} + +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; +} + +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->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->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); +} + +void usnic_uiom_reg_release(struct usnic_uiom_reg *uiomr, + struct ib_ucontext *ucontext) +{ + struct task_struct *task; + struct mm_struct *mm; + unsigned long diff; + + __usnic_uiom_reg_release(uiomr->pd, uiomr, 1); + + task = get_pid_task(ucontext->tgid, PIDTYPE_PID); + if (!task) + goto out; + mm = get_task_mm(task); + put_task_struct(task); + if (!mm) + goto out; + + 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 (ucontext->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); + + mm->pinned_vm -= diff; + up_write(&mm->mmap_sem); + mmput(mm); +out: + kfree(uiomr); +} + +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; +} + +void usnic_uiom_dealloc_pd(struct usnic_uiom_pd *pd) +{ + iommu_domain_free(pd->domain); + kfree(pd); +} + +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; +} + +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); +} + +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; +} + +void usnic_uiom_free_dev_list(struct device **devs) +{ + kfree(devs); +} + +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; +} + +void usnic_uiom_fini(void) +{ + flush_workqueue(usnic_uiom_wq); + destroy_workqueue(usnic_uiom_wq); +} |