mirror of https://gitee.com/openkylin/linux.git
839 lines
24 KiB
C
839 lines
24 KiB
C
/*
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* Copyright (c) 2014 Mellanox Technologies. All rights reserved.
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*
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* This software is available to you under a choice of one of two
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* licenses. You may choose to be licensed under the terms of the GNU
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* General Public License (GPL) Version 2, available from the file
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* COPYING in the main directory of this source tree, or the
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* OpenIB.org BSD license below:
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*
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* Redistribution and use in source and binary forms, with or
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* without modification, are permitted provided that the following
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* conditions are met:
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*
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* - Redistributions of source code must retain the above
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* copyright notice, this list of conditions and the following
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* disclaimer.
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*
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* - Redistributions in binary form must reproduce the above
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* copyright notice, this list of conditions and the following
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* disclaimer in the documentation and/or other materials
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* provided with the distribution.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
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* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
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* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
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* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
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* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
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* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
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* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
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* SOFTWARE.
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*/
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#include <linux/types.h>
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#include <linux/sched.h>
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#include <linux/sched/mm.h>
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#include <linux/sched/task.h>
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#include <linux/pid.h>
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#include <linux/slab.h>
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#include <linux/export.h>
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#include <linux/vmalloc.h>
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#include <linux/hugetlb.h>
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#include <linux/interval_tree.h>
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#include <linux/pagemap.h>
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#include <rdma/ib_verbs.h>
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#include <rdma/ib_umem.h>
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#include <rdma/ib_umem_odp.h>
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#include "uverbs.h"
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static void ib_umem_notifier_start_account(struct ib_umem_odp *umem_odp)
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{
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mutex_lock(&umem_odp->umem_mutex);
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if (umem_odp->notifiers_count++ == 0)
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/*
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* Initialize the completion object for waiting on
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* notifiers. Since notifier_count is zero, no one should be
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* waiting right now.
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*/
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reinit_completion(&umem_odp->notifier_completion);
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mutex_unlock(&umem_odp->umem_mutex);
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}
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static void ib_umem_notifier_end_account(struct ib_umem_odp *umem_odp)
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{
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mutex_lock(&umem_odp->umem_mutex);
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/*
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* This sequence increase will notify the QP page fault that the page
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* that is going to be mapped in the spte could have been freed.
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*/
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++umem_odp->notifiers_seq;
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if (--umem_odp->notifiers_count == 0)
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complete_all(&umem_odp->notifier_completion);
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mutex_unlock(&umem_odp->umem_mutex);
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}
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static void ib_umem_notifier_release(struct mmu_notifier *mn,
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struct mm_struct *mm)
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{
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struct ib_ucontext_per_mm *per_mm =
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container_of(mn, struct ib_ucontext_per_mm, mn);
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struct rb_node *node;
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down_read(&per_mm->umem_rwsem);
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if (!per_mm->active)
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goto out;
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for (node = rb_first_cached(&per_mm->umem_tree); node;
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node = rb_next(node)) {
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struct ib_umem_odp *umem_odp =
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rb_entry(node, struct ib_umem_odp, interval_tree.rb);
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/*
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* Increase the number of notifiers running, to prevent any
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* further fault handling on this MR.
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*/
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ib_umem_notifier_start_account(umem_odp);
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complete_all(&umem_odp->notifier_completion);
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umem_odp->umem.context->invalidate_range(
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umem_odp, ib_umem_start(umem_odp),
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ib_umem_end(umem_odp));
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}
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out:
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up_read(&per_mm->umem_rwsem);
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}
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static int invalidate_range_start_trampoline(struct ib_umem_odp *item,
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u64 start, u64 end, void *cookie)
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{
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ib_umem_notifier_start_account(item);
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item->umem.context->invalidate_range(item, start, end);
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return 0;
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}
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static int ib_umem_notifier_invalidate_range_start(struct mmu_notifier *mn,
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const struct mmu_notifier_range *range)
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{
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struct ib_ucontext_per_mm *per_mm =
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container_of(mn, struct ib_ucontext_per_mm, mn);
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int rc;
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if (mmu_notifier_range_blockable(range))
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down_read(&per_mm->umem_rwsem);
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else if (!down_read_trylock(&per_mm->umem_rwsem))
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return -EAGAIN;
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if (!per_mm->active) {
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up_read(&per_mm->umem_rwsem);
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/*
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* At this point active is permanently set and visible to this
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* CPU without a lock, that fact is relied on to skip the unlock
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* in range_end.
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*/
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return 0;
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}
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rc = rbt_ib_umem_for_each_in_range(&per_mm->umem_tree, range->start,
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range->end,
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invalidate_range_start_trampoline,
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mmu_notifier_range_blockable(range),
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NULL);
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if (rc)
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up_read(&per_mm->umem_rwsem);
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return rc;
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}
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static int invalidate_range_end_trampoline(struct ib_umem_odp *item, u64 start,
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u64 end, void *cookie)
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{
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ib_umem_notifier_end_account(item);
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return 0;
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}
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static void ib_umem_notifier_invalidate_range_end(struct mmu_notifier *mn,
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const struct mmu_notifier_range *range)
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{
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struct ib_ucontext_per_mm *per_mm =
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container_of(mn, struct ib_ucontext_per_mm, mn);
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if (unlikely(!per_mm->active))
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return;
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rbt_ib_umem_for_each_in_range(&per_mm->umem_tree, range->start,
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range->end,
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invalidate_range_end_trampoline, true, NULL);
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up_read(&per_mm->umem_rwsem);
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}
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static const struct mmu_notifier_ops ib_umem_notifiers = {
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.release = ib_umem_notifier_release,
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.invalidate_range_start = ib_umem_notifier_invalidate_range_start,
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.invalidate_range_end = ib_umem_notifier_invalidate_range_end,
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};
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static void remove_umem_from_per_mm(struct ib_umem_odp *umem_odp)
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{
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struct ib_ucontext_per_mm *per_mm = umem_odp->per_mm;
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down_write(&per_mm->umem_rwsem);
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interval_tree_remove(&umem_odp->interval_tree, &per_mm->umem_tree);
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complete_all(&umem_odp->notifier_completion);
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up_write(&per_mm->umem_rwsem);
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}
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static struct ib_ucontext_per_mm *alloc_per_mm(struct ib_ucontext *ctx,
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struct mm_struct *mm)
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{
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struct ib_ucontext_per_mm *per_mm;
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int ret;
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per_mm = kzalloc(sizeof(*per_mm), GFP_KERNEL);
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if (!per_mm)
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return ERR_PTR(-ENOMEM);
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per_mm->context = ctx;
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per_mm->mm = mm;
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per_mm->umem_tree = RB_ROOT_CACHED;
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init_rwsem(&per_mm->umem_rwsem);
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per_mm->active = true;
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rcu_read_lock();
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per_mm->tgid = get_task_pid(current->group_leader, PIDTYPE_PID);
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rcu_read_unlock();
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WARN_ON(mm != current->mm);
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per_mm->mn.ops = &ib_umem_notifiers;
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ret = mmu_notifier_register(&per_mm->mn, per_mm->mm);
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if (ret) {
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dev_err(&ctx->device->dev,
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"Failed to register mmu_notifier %d\n", ret);
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goto out_pid;
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}
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list_add(&per_mm->ucontext_list, &ctx->per_mm_list);
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return per_mm;
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out_pid:
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put_pid(per_mm->tgid);
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kfree(per_mm);
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return ERR_PTR(ret);
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}
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static struct ib_ucontext_per_mm *get_per_mm(struct ib_umem_odp *umem_odp)
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{
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struct ib_ucontext *ctx = umem_odp->umem.context;
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struct ib_ucontext_per_mm *per_mm;
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lockdep_assert_held(&ctx->per_mm_list_lock);
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/*
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* Generally speaking we expect only one or two per_mm in this list,
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* so no reason to optimize this search today.
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*/
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list_for_each_entry(per_mm, &ctx->per_mm_list, ucontext_list) {
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if (per_mm->mm == umem_odp->umem.owning_mm)
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return per_mm;
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}
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return alloc_per_mm(ctx, umem_odp->umem.owning_mm);
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}
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static void free_per_mm(struct rcu_head *rcu)
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{
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kfree(container_of(rcu, struct ib_ucontext_per_mm, rcu));
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}
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static void put_per_mm(struct ib_umem_odp *umem_odp)
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{
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struct ib_ucontext_per_mm *per_mm = umem_odp->per_mm;
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struct ib_ucontext *ctx = umem_odp->umem.context;
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bool need_free;
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mutex_lock(&ctx->per_mm_list_lock);
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umem_odp->per_mm = NULL;
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per_mm->odp_mrs_count--;
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need_free = per_mm->odp_mrs_count == 0;
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if (need_free)
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list_del(&per_mm->ucontext_list);
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mutex_unlock(&ctx->per_mm_list_lock);
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if (!need_free)
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return;
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/*
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* NOTE! mmu_notifier_unregister() can happen between a start/end
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* callback, resulting in an start/end, and thus an unbalanced
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* lock. This doesn't really matter to us since we are about to kfree
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* the memory that holds the lock, however LOCKDEP doesn't like this.
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*/
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down_write(&per_mm->umem_rwsem);
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per_mm->active = false;
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up_write(&per_mm->umem_rwsem);
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WARN_ON(!RB_EMPTY_ROOT(&per_mm->umem_tree.rb_root));
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mmu_notifier_unregister_no_release(&per_mm->mn, per_mm->mm);
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put_pid(per_mm->tgid);
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mmu_notifier_call_srcu(&per_mm->rcu, free_per_mm);
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}
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static inline int ib_init_umem_odp(struct ib_umem_odp *umem_odp,
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struct ib_ucontext_per_mm *per_mm)
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{
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struct ib_ucontext *ctx = umem_odp->umem.context;
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int ret;
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umem_odp->umem.is_odp = 1;
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if (!umem_odp->is_implicit_odp) {
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size_t pages = ib_umem_odp_num_pages(umem_odp);
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if (!pages)
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return -EINVAL;
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/*
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* Note that the representation of the intervals in the
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* interval tree considers the ending point as contained in
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* the interval, while the function ib_umem_end returns the
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* first address which is not contained in the umem.
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*/
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umem_odp->interval_tree.start = ib_umem_start(umem_odp);
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umem_odp->interval_tree.last = ib_umem_end(umem_odp) - 1;
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umem_odp->page_list = vzalloc(
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array_size(sizeof(*umem_odp->page_list), pages));
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if (!umem_odp->page_list)
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return -ENOMEM;
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umem_odp->dma_list =
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vzalloc(array_size(sizeof(*umem_odp->dma_list), pages));
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if (!umem_odp->dma_list) {
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ret = -ENOMEM;
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goto out_page_list;
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}
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}
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mutex_lock(&ctx->per_mm_list_lock);
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if (!per_mm) {
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per_mm = get_per_mm(umem_odp);
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if (IS_ERR(per_mm)) {
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ret = PTR_ERR(per_mm);
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goto out_unlock;
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}
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}
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umem_odp->per_mm = per_mm;
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per_mm->odp_mrs_count++;
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mutex_unlock(&ctx->per_mm_list_lock);
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mutex_init(&umem_odp->umem_mutex);
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init_completion(&umem_odp->notifier_completion);
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if (!umem_odp->is_implicit_odp) {
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down_write(&per_mm->umem_rwsem);
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interval_tree_insert(&umem_odp->interval_tree,
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&per_mm->umem_tree);
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up_write(&per_mm->umem_rwsem);
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}
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mmgrab(umem_odp->umem.owning_mm);
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return 0;
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out_unlock:
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mutex_unlock(&ctx->per_mm_list_lock);
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vfree(umem_odp->dma_list);
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out_page_list:
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vfree(umem_odp->page_list);
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return ret;
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}
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/**
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* ib_umem_odp_alloc_implicit - Allocate a parent implicit ODP umem
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*
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* Implicit ODP umems do not have a VA range and do not have any page lists.
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* They exist only to hold the per_mm reference to help the driver create
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* children umems.
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*
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* @udata: udata from the syscall being used to create the umem
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* @access: ib_reg_mr access flags
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*/
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struct ib_umem_odp *ib_umem_odp_alloc_implicit(struct ib_udata *udata,
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int access)
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{
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struct ib_ucontext *context =
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container_of(udata, struct uverbs_attr_bundle, driver_udata)
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->context;
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struct ib_umem *umem;
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struct ib_umem_odp *umem_odp;
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int ret;
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if (access & IB_ACCESS_HUGETLB)
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return ERR_PTR(-EINVAL);
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if (!context)
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return ERR_PTR(-EIO);
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if (WARN_ON_ONCE(!context->invalidate_range))
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return ERR_PTR(-EINVAL);
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umem_odp = kzalloc(sizeof(*umem_odp), GFP_KERNEL);
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if (!umem_odp)
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return ERR_PTR(-ENOMEM);
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umem = &umem_odp->umem;
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umem->context = context;
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umem->writable = ib_access_writable(access);
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umem->owning_mm = current->mm;
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umem_odp->is_implicit_odp = 1;
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umem_odp->page_shift = PAGE_SHIFT;
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ret = ib_init_umem_odp(umem_odp, NULL);
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if (ret) {
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kfree(umem_odp);
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return ERR_PTR(ret);
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}
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return umem_odp;
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}
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EXPORT_SYMBOL(ib_umem_odp_alloc_implicit);
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/**
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* ib_umem_odp_alloc_child - Allocate a child ODP umem under an implicit
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* parent ODP umem
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*
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* @root: The parent umem enclosing the child. This must be allocated using
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* ib_alloc_implicit_odp_umem()
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* @addr: The starting userspace VA
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* @size: The length of the userspace VA
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*/
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struct ib_umem_odp *ib_umem_odp_alloc_child(struct ib_umem_odp *root,
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unsigned long addr, size_t size)
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{
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/*
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* Caller must ensure that root cannot be freed during the call to
|
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* ib_alloc_odp_umem.
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*/
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struct ib_umem_odp *odp_data;
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struct ib_umem *umem;
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int ret;
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|
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if (WARN_ON(!root->is_implicit_odp))
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return ERR_PTR(-EINVAL);
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|
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odp_data = kzalloc(sizeof(*odp_data), GFP_KERNEL);
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if (!odp_data)
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return ERR_PTR(-ENOMEM);
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umem = &odp_data->umem;
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umem->context = root->umem.context;
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umem->length = size;
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umem->address = addr;
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umem->writable = root->umem.writable;
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umem->owning_mm = root->umem.owning_mm;
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odp_data->page_shift = PAGE_SHIFT;
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ret = ib_init_umem_odp(odp_data, root->per_mm);
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if (ret) {
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kfree(odp_data);
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return ERR_PTR(ret);
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}
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return odp_data;
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}
|
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EXPORT_SYMBOL(ib_umem_odp_alloc_child);
|
|
|
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/**
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* ib_umem_odp_get - Create a umem_odp for a userspace va
|
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*
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* @udata: userspace context to pin memory for
|
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* @addr: userspace virtual address to start at
|
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* @size: length of region to pin
|
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* @access: IB_ACCESS_xxx flags for memory being pinned
|
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*
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* The driver should use when the access flags indicate ODP memory. It avoids
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* pinning, instead, stores the mm for future page fault handling in
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* conjunction with MMU notifiers.
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*/
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struct ib_umem_odp *ib_umem_odp_get(struct ib_udata *udata, unsigned long addr,
|
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size_t size, int access)
|
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{
|
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struct ib_umem_odp *umem_odp;
|
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struct ib_ucontext *context;
|
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struct mm_struct *mm;
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int ret;
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|
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if (!udata)
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return ERR_PTR(-EIO);
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|
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context = container_of(udata, struct uverbs_attr_bundle, driver_udata)
|
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->context;
|
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if (!context)
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return ERR_PTR(-EIO);
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|
|
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if (WARN_ON_ONCE(!(access & IB_ACCESS_ON_DEMAND)) ||
|
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WARN_ON_ONCE(!context->invalidate_range))
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return ERR_PTR(-EINVAL);
|
|
|
|
umem_odp = kzalloc(sizeof(struct ib_umem_odp), GFP_KERNEL);
|
|
if (!umem_odp)
|
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return ERR_PTR(-ENOMEM);
|
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|
|
umem_odp->umem.context = context;
|
|
umem_odp->umem.length = size;
|
|
umem_odp->umem.address = addr;
|
|
umem_odp->umem.writable = ib_access_writable(access);
|
|
umem_odp->umem.owning_mm = mm = current->mm;
|
|
|
|
umem_odp->page_shift = PAGE_SHIFT;
|
|
if (access & IB_ACCESS_HUGETLB) {
|
|
struct vm_area_struct *vma;
|
|
struct hstate *h;
|
|
|
|
down_read(&mm->mmap_sem);
|
|
vma = find_vma(mm, ib_umem_start(umem_odp));
|
|
if (!vma || !is_vm_hugetlb_page(vma)) {
|
|
up_read(&mm->mmap_sem);
|
|
ret = -EINVAL;
|
|
goto err_free;
|
|
}
|
|
h = hstate_vma(vma);
|
|
umem_odp->page_shift = huge_page_shift(h);
|
|
up_read(&mm->mmap_sem);
|
|
}
|
|
|
|
ret = ib_init_umem_odp(umem_odp, NULL);
|
|
if (ret)
|
|
goto err_free;
|
|
return umem_odp;
|
|
|
|
err_free:
|
|
kfree(umem_odp);
|
|
return ERR_PTR(ret);
|
|
}
|
|
EXPORT_SYMBOL(ib_umem_odp_get);
|
|
|
|
void ib_umem_odp_release(struct ib_umem_odp *umem_odp)
|
|
{
|
|
/*
|
|
* Ensure that no more pages are mapped in the umem.
|
|
*
|
|
* It is the driver's responsibility to ensure, before calling us,
|
|
* that the hardware will not attempt to access the MR any more.
|
|
*/
|
|
if (!umem_odp->is_implicit_odp) {
|
|
ib_umem_odp_unmap_dma_pages(umem_odp, ib_umem_start(umem_odp),
|
|
ib_umem_end(umem_odp));
|
|
remove_umem_from_per_mm(umem_odp);
|
|
vfree(umem_odp->dma_list);
|
|
vfree(umem_odp->page_list);
|
|
}
|
|
put_per_mm(umem_odp);
|
|
}
|
|
|
|
/*
|
|
* Map for DMA and insert a single page into the on-demand paging page tables.
|
|
*
|
|
* @umem: the umem to insert the page to.
|
|
* @page_index: index in the umem to add the page to.
|
|
* @page: the page struct to map and add.
|
|
* @access_mask: access permissions needed for this page.
|
|
* @current_seq: sequence number for synchronization with invalidations.
|
|
* the sequence number is taken from
|
|
* umem_odp->notifiers_seq.
|
|
*
|
|
* The function returns -EFAULT if the DMA mapping operation fails. It returns
|
|
* -EAGAIN if a concurrent invalidation prevents us from updating the page.
|
|
*
|
|
* The page is released via put_user_page even if the operation failed. For
|
|
* on-demand pinning, the page is released whenever it isn't stored in the
|
|
* umem.
|
|
*/
|
|
static int ib_umem_odp_map_dma_single_page(
|
|
struct ib_umem_odp *umem_odp,
|
|
int page_index,
|
|
struct page *page,
|
|
u64 access_mask,
|
|
unsigned long current_seq)
|
|
{
|
|
struct ib_ucontext *context = umem_odp->umem.context;
|
|
struct ib_device *dev = context->device;
|
|
dma_addr_t dma_addr;
|
|
int remove_existing_mapping = 0;
|
|
int ret = 0;
|
|
|
|
/*
|
|
* Note: we avoid writing if seq is different from the initial seq, to
|
|
* handle case of a racing notifier. This check also allows us to bail
|
|
* early if we have a notifier running in parallel with us.
|
|
*/
|
|
if (ib_umem_mmu_notifier_retry(umem_odp, current_seq)) {
|
|
ret = -EAGAIN;
|
|
goto out;
|
|
}
|
|
if (!(umem_odp->dma_list[page_index])) {
|
|
dma_addr =
|
|
ib_dma_map_page(dev, page, 0, BIT(umem_odp->page_shift),
|
|
DMA_BIDIRECTIONAL);
|
|
if (ib_dma_mapping_error(dev, dma_addr)) {
|
|
ret = -EFAULT;
|
|
goto out;
|
|
}
|
|
umem_odp->dma_list[page_index] = dma_addr | access_mask;
|
|
umem_odp->page_list[page_index] = page;
|
|
umem_odp->npages++;
|
|
} else if (umem_odp->page_list[page_index] == page) {
|
|
umem_odp->dma_list[page_index] |= access_mask;
|
|
} else {
|
|
pr_err("error: got different pages in IB device and from get_user_pages. IB device page: %p, gup page: %p\n",
|
|
umem_odp->page_list[page_index], page);
|
|
/* Better remove the mapping now, to prevent any further
|
|
* damage. */
|
|
remove_existing_mapping = 1;
|
|
}
|
|
|
|
out:
|
|
put_user_page(page);
|
|
|
|
if (remove_existing_mapping) {
|
|
ib_umem_notifier_start_account(umem_odp);
|
|
context->invalidate_range(
|
|
umem_odp,
|
|
ib_umem_start(umem_odp) +
|
|
(page_index << umem_odp->page_shift),
|
|
ib_umem_start(umem_odp) +
|
|
((page_index + 1) << umem_odp->page_shift));
|
|
ib_umem_notifier_end_account(umem_odp);
|
|
ret = -EAGAIN;
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* ib_umem_odp_map_dma_pages - Pin and DMA map userspace memory in an ODP MR.
|
|
*
|
|
* Pins the range of pages passed in the argument, and maps them to
|
|
* DMA addresses. The DMA addresses of the mapped pages is updated in
|
|
* umem_odp->dma_list.
|
|
*
|
|
* Returns the number of pages mapped in success, negative error code
|
|
* for failure.
|
|
* An -EAGAIN error code is returned when a concurrent mmu notifier prevents
|
|
* the function from completing its task.
|
|
* An -ENOENT error code indicates that userspace process is being terminated
|
|
* and mm was already destroyed.
|
|
* @umem_odp: the umem to map and pin
|
|
* @user_virt: the address from which we need to map.
|
|
* @bcnt: the minimal number of bytes to pin and map. The mapping might be
|
|
* bigger due to alignment, and may also be smaller in case of an error
|
|
* pinning or mapping a page. The actual pages mapped is returned in
|
|
* the return value.
|
|
* @access_mask: bit mask of the requested access permissions for the given
|
|
* range.
|
|
* @current_seq: the MMU notifiers sequance value for synchronization with
|
|
* invalidations. the sequance number is read from
|
|
* umem_odp->notifiers_seq before calling this function
|
|
*/
|
|
int ib_umem_odp_map_dma_pages(struct ib_umem_odp *umem_odp, u64 user_virt,
|
|
u64 bcnt, u64 access_mask,
|
|
unsigned long current_seq)
|
|
{
|
|
struct task_struct *owning_process = NULL;
|
|
struct mm_struct *owning_mm = umem_odp->umem.owning_mm;
|
|
struct page **local_page_list = NULL;
|
|
u64 page_mask, off;
|
|
int j, k, ret = 0, start_idx, npages = 0;
|
|
unsigned int flags = 0, page_shift;
|
|
phys_addr_t p = 0;
|
|
|
|
if (access_mask == 0)
|
|
return -EINVAL;
|
|
|
|
if (user_virt < ib_umem_start(umem_odp) ||
|
|
user_virt + bcnt > ib_umem_end(umem_odp))
|
|
return -EFAULT;
|
|
|
|
local_page_list = (struct page **)__get_free_page(GFP_KERNEL);
|
|
if (!local_page_list)
|
|
return -ENOMEM;
|
|
|
|
page_shift = umem_odp->page_shift;
|
|
page_mask = ~(BIT(page_shift) - 1);
|
|
off = user_virt & (~page_mask);
|
|
user_virt = user_virt & page_mask;
|
|
bcnt += off; /* Charge for the first page offset as well. */
|
|
|
|
/*
|
|
* owning_process is allowed to be NULL, this means somehow the mm is
|
|
* existing beyond the lifetime of the originating process.. Presumably
|
|
* mmget_not_zero will fail in this case.
|
|
*/
|
|
owning_process = get_pid_task(umem_odp->per_mm->tgid, PIDTYPE_PID);
|
|
if (!owning_process || !mmget_not_zero(owning_mm)) {
|
|
ret = -EINVAL;
|
|
goto out_put_task;
|
|
}
|
|
|
|
if (access_mask & ODP_WRITE_ALLOWED_BIT)
|
|
flags |= FOLL_WRITE;
|
|
|
|
start_idx = (user_virt - ib_umem_start(umem_odp)) >> page_shift;
|
|
k = start_idx;
|
|
|
|
while (bcnt > 0) {
|
|
const size_t gup_num_pages = min_t(size_t,
|
|
(bcnt + BIT(page_shift) - 1) >> page_shift,
|
|
PAGE_SIZE / sizeof(struct page *));
|
|
|
|
down_read(&owning_mm->mmap_sem);
|
|
/*
|
|
* Note: this might result in redundent page getting. We can
|
|
* avoid this by checking dma_list to be 0 before calling
|
|
* get_user_pages. However, this make the code much more
|
|
* complex (and doesn't gain us much performance in most use
|
|
* cases).
|
|
*/
|
|
npages = get_user_pages_remote(owning_process, owning_mm,
|
|
user_virt, gup_num_pages,
|
|
flags, local_page_list, NULL, NULL);
|
|
up_read(&owning_mm->mmap_sem);
|
|
|
|
if (npages < 0) {
|
|
if (npages != -EAGAIN)
|
|
pr_warn("fail to get %zu user pages with error %d\n", gup_num_pages, npages);
|
|
else
|
|
pr_debug("fail to get %zu user pages with error %d\n", gup_num_pages, npages);
|
|
break;
|
|
}
|
|
|
|
bcnt -= min_t(size_t, npages << PAGE_SHIFT, bcnt);
|
|
mutex_lock(&umem_odp->umem_mutex);
|
|
for (j = 0; j < npages; j++, user_virt += PAGE_SIZE) {
|
|
if (user_virt & ~page_mask) {
|
|
p += PAGE_SIZE;
|
|
if (page_to_phys(local_page_list[j]) != p) {
|
|
ret = -EFAULT;
|
|
break;
|
|
}
|
|
put_user_page(local_page_list[j]);
|
|
continue;
|
|
}
|
|
|
|
ret = ib_umem_odp_map_dma_single_page(
|
|
umem_odp, k, local_page_list[j],
|
|
access_mask, current_seq);
|
|
if (ret < 0) {
|
|
if (ret != -EAGAIN)
|
|
pr_warn("ib_umem_odp_map_dma_single_page failed with error %d\n", ret);
|
|
else
|
|
pr_debug("ib_umem_odp_map_dma_single_page failed with error %d\n", ret);
|
|
break;
|
|
}
|
|
|
|
p = page_to_phys(local_page_list[j]);
|
|
k++;
|
|
}
|
|
mutex_unlock(&umem_odp->umem_mutex);
|
|
|
|
if (ret < 0) {
|
|
/*
|
|
* Release pages, remembering that the first page
|
|
* to hit an error was already released by
|
|
* ib_umem_odp_map_dma_single_page().
|
|
*/
|
|
if (npages - (j + 1) > 0)
|
|
put_user_pages(&local_page_list[j+1],
|
|
npages - (j + 1));
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (ret >= 0) {
|
|
if (npages < 0 && k == start_idx)
|
|
ret = npages;
|
|
else
|
|
ret = k - start_idx;
|
|
}
|
|
|
|
mmput(owning_mm);
|
|
out_put_task:
|
|
if (owning_process)
|
|
put_task_struct(owning_process);
|
|
free_page((unsigned long)local_page_list);
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL(ib_umem_odp_map_dma_pages);
|
|
|
|
void ib_umem_odp_unmap_dma_pages(struct ib_umem_odp *umem_odp, u64 virt,
|
|
u64 bound)
|
|
{
|
|
int idx;
|
|
u64 addr;
|
|
struct ib_device *dev = umem_odp->umem.context->device;
|
|
|
|
virt = max_t(u64, virt, ib_umem_start(umem_odp));
|
|
bound = min_t(u64, bound, ib_umem_end(umem_odp));
|
|
/* Note that during the run of this function, the
|
|
* notifiers_count of the MR is > 0, preventing any racing
|
|
* faults from completion. We might be racing with other
|
|
* invalidations, so we must make sure we free each page only
|
|
* once. */
|
|
mutex_lock(&umem_odp->umem_mutex);
|
|
for (addr = virt; addr < bound; addr += BIT(umem_odp->page_shift)) {
|
|
idx = (addr - ib_umem_start(umem_odp)) >> umem_odp->page_shift;
|
|
if (umem_odp->page_list[idx]) {
|
|
struct page *page = umem_odp->page_list[idx];
|
|
dma_addr_t dma = umem_odp->dma_list[idx];
|
|
dma_addr_t dma_addr = dma & ODP_DMA_ADDR_MASK;
|
|
|
|
WARN_ON(!dma_addr);
|
|
|
|
ib_dma_unmap_page(dev, dma_addr,
|
|
BIT(umem_odp->page_shift),
|
|
DMA_BIDIRECTIONAL);
|
|
if (dma & ODP_WRITE_ALLOWED_BIT) {
|
|
struct page *head_page = compound_head(page);
|
|
/*
|
|
* set_page_dirty prefers being called with
|
|
* the page lock. However, MMU notifiers are
|
|
* called sometimes with and sometimes without
|
|
* the lock. We rely on the umem_mutex instead
|
|
* to prevent other mmu notifiers from
|
|
* continuing and allowing the page mapping to
|
|
* be removed.
|
|
*/
|
|
set_page_dirty(head_page);
|
|
}
|
|
umem_odp->page_list[idx] = NULL;
|
|
umem_odp->dma_list[idx] = 0;
|
|
umem_odp->npages--;
|
|
}
|
|
}
|
|
mutex_unlock(&umem_odp->umem_mutex);
|
|
}
|
|
EXPORT_SYMBOL(ib_umem_odp_unmap_dma_pages);
|
|
|
|
/* @last is not a part of the interval. See comment for function
|
|
* node_last.
|
|
*/
|
|
int rbt_ib_umem_for_each_in_range(struct rb_root_cached *root,
|
|
u64 start, u64 last,
|
|
umem_call_back cb,
|
|
bool blockable,
|
|
void *cookie)
|
|
{
|
|
int ret_val = 0;
|
|
struct interval_tree_node *node, *next;
|
|
struct ib_umem_odp *umem;
|
|
|
|
if (unlikely(start == last))
|
|
return ret_val;
|
|
|
|
for (node = interval_tree_iter_first(root, start, last - 1);
|
|
node; node = next) {
|
|
/* TODO move the blockable decision up to the callback */
|
|
if (!blockable)
|
|
return -EAGAIN;
|
|
next = interval_tree_iter_next(node, start, last - 1);
|
|
umem = container_of(node, struct ib_umem_odp, interval_tree);
|
|
ret_val = cb(umem, start, last, cookie) || ret_val;
|
|
}
|
|
|
|
return ret_val;
|
|
}
|