Adding upstream version 4.19.249.upstream/4.19.249upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 357 insertions, 0 deletions

diff --git a/drivers/infiniband/hw/hfi1/mmu_rb.c b/drivers/infiniband/hw/hfi1/mmu_rb.c
new file mode 100644
index 000000000..e1c7996c0
--- /dev/null
+++ b/drivers/infiniband/hw/hfi1/mmu_rb.c
@@ -0,0 +1,357 @@
+/*
+ * Copyright(c) 2016 - 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/list.h>
+#include <linux/rculist.h>
+#include <linux/mmu_notifier.h>
+#include <linux/interval_tree_generic.h>
+
+#include "mmu_rb.h"
+#include "trace.h"
+
+struct mmu_rb_handler {
+	struct mmu_notifier mn;
+	struct rb_root_cached root;
+	void *ops_arg;
+	spinlock_t lock;        /* protect the RB tree */
+	struct mmu_rb_ops *ops;
+	struct mm_struct *mm;
+	struct list_head lru_list;
+	struct work_struct del_work;
+	struct list_head del_list;
+	struct workqueue_struct *wq;
+};
+
+static unsigned long mmu_node_start(struct mmu_rb_node *);
+static unsigned long mmu_node_last(struct mmu_rb_node *);
+static int mmu_notifier_range_start(struct mmu_notifier *,
+				     struct mm_struct *,
+				     unsigned long, unsigned long, bool);
+static struct mmu_rb_node *__mmu_rb_search(struct mmu_rb_handler *,
+					   unsigned long, unsigned long);
+static void do_remove(struct mmu_rb_handler *handler,
+		      struct list_head *del_list);
+static void handle_remove(struct work_struct *work);
+
+static const struct mmu_notifier_ops mn_opts = {
+	.flags = MMU_INVALIDATE_DOES_NOT_BLOCK,
+	.invalidate_range_start = mmu_notifier_range_start,
+};
+
+INTERVAL_TREE_DEFINE(struct mmu_rb_node, node, unsigned long, __last,
+		     mmu_node_start, mmu_node_last, static, __mmu_int_rb);
+
+static unsigned long mmu_node_start(struct mmu_rb_node *node)
+{
+	return node->addr & PAGE_MASK;
+}
+
+static unsigned long mmu_node_last(struct mmu_rb_node *node)
+{
+	return PAGE_ALIGN(node->addr + node->len) - 1;
+}
+
+int hfi1_mmu_rb_register(void *ops_arg, struct mm_struct *mm,
+			 struct mmu_rb_ops *ops,
+			 struct workqueue_struct *wq,
+			 struct mmu_rb_handler **handler)
+{
+	struct mmu_rb_handler *handlr;
+	int ret;
+
+	handlr = kmalloc(sizeof(*handlr), GFP_KERNEL);
+	if (!handlr)
+		return -ENOMEM;
+
+	handlr->root = RB_ROOT_CACHED;
+	handlr->ops = ops;
+	handlr->ops_arg = ops_arg;
+	INIT_HLIST_NODE(&handlr->mn.hlist);
+	spin_lock_init(&handlr->lock);
+	handlr->mn.ops = &mn_opts;
+	handlr->mm = mm;
+	INIT_WORK(&handlr->del_work, handle_remove);
+	INIT_LIST_HEAD(&handlr->del_list);
+	INIT_LIST_HEAD(&handlr->lru_list);
+	handlr->wq = wq;
+
+	ret = mmu_notifier_register(&handlr->mn, handlr->mm);
+	if (ret) {
+		kfree(handlr);
+		return ret;
+	}
+
+	*handler = handlr;
+	return 0;
+}
+
+void hfi1_mmu_rb_unregister(struct mmu_rb_handler *handler)
+{
+	struct mmu_rb_node *rbnode;
+	struct rb_node *node;
+	unsigned long flags;
+	struct list_head del_list;
+
+	/* Unregister first so we don't get any more notifications. */
+	mmu_notifier_unregister(&handler->mn, handler->mm);
+
+	/*
+	 * Make sure the wq delete handler is finished running.  It will not
+	 * be triggered once the mmu notifiers are unregistered above.
+	 */
+	flush_work(&handler->del_work);
+
+	INIT_LIST_HEAD(&del_list);
+
+	spin_lock_irqsave(&handler->lock, flags);
+	while ((node = rb_first_cached(&handler->root))) {
+		rbnode = rb_entry(node, struct mmu_rb_node, node);
+		rb_erase_cached(node, &handler->root);
+		/* move from LRU list to delete list */
+		list_move(&rbnode->list, &del_list);
+	}
+	spin_unlock_irqrestore(&handler->lock, flags);
+
+	do_remove(handler, &del_list);
+
+	kfree(handler);
+}
+
+int hfi1_mmu_rb_insert(struct mmu_rb_handler *handler,
+		       struct mmu_rb_node *mnode)
+{
+	struct mmu_rb_node *node;
+	unsigned long flags;
+	int ret = 0;
+
+	trace_hfi1_mmu_rb_insert(mnode->addr, mnode->len);
+	spin_lock_irqsave(&handler->lock, flags);
+	node = __mmu_rb_search(handler, mnode->addr, mnode->len);
+	if (node) {
+		ret = -EINVAL;
+		goto unlock;
+	}
+	__mmu_int_rb_insert(mnode, &handler->root);
+	list_add(&mnode->list, &handler->lru_list);
+
+	ret = handler->ops->insert(handler->ops_arg, mnode);
+	if (ret) {
+		__mmu_int_rb_remove(mnode, &handler->root);
+		list_del(&mnode->list); /* remove from LRU list */
+	}
+unlock:
+	spin_unlock_irqrestore(&handler->lock, flags);
+	return ret;
+}
+
+/* Caller must hold handler lock */
+static struct mmu_rb_node *__mmu_rb_search(struct mmu_rb_handler *handler,
+					   unsigned long addr,
+					   unsigned long len)
+{
+	struct mmu_rb_node *node = NULL;
+
+	trace_hfi1_mmu_rb_search(addr, len);
+	if (!handler->ops->filter) {
+		node = __mmu_int_rb_iter_first(&handler->root, addr,
+					       (addr + len) - 1);
+	} else {
+		for (node = __mmu_int_rb_iter_first(&handler->root, addr,
+						    (addr + len) - 1);
+		     node;
+		     node = __mmu_int_rb_iter_next(node, addr,
+						   (addr + len) - 1)) {
+			if (handler->ops->filter(node, addr, len))
+				return node;
+		}
+	}
+	return node;
+}
+
+bool hfi1_mmu_rb_remove_unless_exact(struct mmu_rb_handler *handler,
+				     unsigned long addr, unsigned long len,
+				     struct mmu_rb_node **rb_node)
+{
+	struct mmu_rb_node *node;
+	unsigned long flags;
+	bool ret = false;
+
+	spin_lock_irqsave(&handler->lock, flags);
+	node = __mmu_rb_search(handler, addr, len);
+	if (node) {
+		if (node->addr == addr && node->len == len)
+			goto unlock;
+		__mmu_int_rb_remove(node, &handler->root);
+		list_del(&node->list); /* remove from LRU list */
+		ret = true;
+	}
+unlock:
+	spin_unlock_irqrestore(&handler->lock, flags);
+	*rb_node = node;
+	return ret;
+}
+
+void hfi1_mmu_rb_evict(struct mmu_rb_handler *handler, void *evict_arg)
+{
+	struct mmu_rb_node *rbnode, *ptr;
+	struct list_head del_list;
+	unsigned long flags;
+	bool stop = false;
+
+	INIT_LIST_HEAD(&del_list);
+
+	spin_lock_irqsave(&handler->lock, flags);
+	list_for_each_entry_safe_reverse(rbnode, ptr, &handler->lru_list,
+					 list) {
+		if (handler->ops->evict(handler->ops_arg, rbnode, evict_arg,
+					&stop)) {
+			__mmu_int_rb_remove(rbnode, &handler->root);
+			/* move from LRU list to delete list */
+			list_move(&rbnode->list, &del_list);
+		}
+		if (stop)
+			break;
+	}
+	spin_unlock_irqrestore(&handler->lock, flags);
+
+	while (!list_empty(&del_list)) {
+		rbnode = list_first_entry(&del_list, struct mmu_rb_node, list);
+		list_del(&rbnode->list);
+		handler->ops->remove(handler->ops_arg, rbnode);
+	}
+}
+
+/*
+ * It is up to the caller to ensure that this function does not race with the
+ * mmu invalidate notifier which may be calling the users remove callback on
+ * 'node'.
+ */
+void hfi1_mmu_rb_remove(struct mmu_rb_handler *handler,
+			struct mmu_rb_node *node)
+{
+	unsigned long flags;
+
+	/* Validity of handler and node pointers has been checked by caller. */
+	trace_hfi1_mmu_rb_remove(node->addr, node->len);
+	spin_lock_irqsave(&handler->lock, flags);
+	__mmu_int_rb_remove(node, &handler->root);
+	list_del(&node->list); /* remove from LRU list */
+	spin_unlock_irqrestore(&handler->lock, flags);
+
+	handler->ops->remove(handler->ops_arg, node);
+}
+
+static int mmu_notifier_range_start(struct mmu_notifier *mn,
+				     struct mm_struct *mm,
+				     unsigned long start,
+				     unsigned long end,
+				     bool blockable)
+{
+	struct mmu_rb_handler *handler =
+		container_of(mn, struct mmu_rb_handler, mn);
+	struct rb_root_cached *root = &handler->root;
+	struct mmu_rb_node *node, *ptr = NULL;
+	unsigned long flags;
+	bool added = false;
+
+	spin_lock_irqsave(&handler->lock, flags);
+	for (node = __mmu_int_rb_iter_first(root, start, end - 1);
+	     node; node = ptr) {
+		/* Guard against node removal. */
+		ptr = __mmu_int_rb_iter_next(node, start, end - 1);
+		trace_hfi1_mmu_mem_invalidate(node->addr, node->len);
+		if (handler->ops->invalidate(handler->ops_arg, node)) {
+			__mmu_int_rb_remove(node, root);
+			/* move from LRU list to delete list */
+			list_move(&node->list, &handler->del_list);
+			added = true;
+		}
+	}
+	spin_unlock_irqrestore(&handler->lock, flags);
+
+	if (added)
+		queue_work(handler->wq, &handler->del_work);
+
+	return 0;
+}
+
+/*
+ * Call the remove function for the given handler and the list.  This
+ * is expected to be called with a delete list extracted from handler.
+ * The caller should not be holding the handler lock.
+ */
+static void do_remove(struct mmu_rb_handler *handler,
+		      struct list_head *del_list)
+{
+	struct mmu_rb_node *node;
+
+	while (!list_empty(del_list)) {
+		node = list_first_entry(del_list, struct mmu_rb_node, list);
+		list_del(&node->list);
+		handler->ops->remove(handler->ops_arg, node);
+	}
+}
+
+/*
+ * Work queue function to remove all nodes that have been queued up to
+ * be removed.  The key feature is that mm->mmap_sem is not being held
+ * and the remove callback can sleep while taking it, if needed.
+ */
+static void handle_remove(struct work_struct *work)
+{
+	struct mmu_rb_handler *handler = container_of(work,
+						struct mmu_rb_handler,
+						del_work);
+	struct list_head del_list;
+	unsigned long flags;
+
+	/* remove anything that is queued to get removed */
+	spin_lock_irqsave(&handler->lock, flags);
+	list_replace_init(&handler->del_list, &del_list);
+	spin_unlock_irqrestore(&handler->lock, flags);
+
+	do_remove(handler, &del_list);
+}