/* * Copyright 2014 Advanced Micro Devices, Inc. * All Rights Reserved. * * Permission is hereby granted, free of charge, to any person obtaining a * copy of this software and associated documentation files (the * "Software"), to deal in the Software without restriction, including * without limitation the rights to use, copy, modify, merge, publish, * distribute, sub license, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so, subject to * the following conditions: * * 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 NON-INFRINGEMENT. IN NO EVENT SHALL * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS 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. * * The above copyright notice and this permission notice (including the * next paragraph) shall be included in all copies or substantial portions * of the Software. * *//* * Authors: *    Christian König <christian.koenig@amd.com> */ /** * DOC: MMU Notifier * * For coherent userptr handling registers an MMU notifier to inform the driver * about updates on the page tables of a process. * * When somebody tries to invalidate the page tables we block the update until * all operations on the pages in question are completed, then those pages are * marked as accessed and also dirty if it wasn't a read only access. * * New command submissions using the userptrs in question are delayed until all * page table invalidation are completed and we once more see a coherent process * address space. */ #include <linux/firmware.h>#include <linux/module.h>#include <drm/drm.h> #include "amdgpu.h"#include "amdgpu_amdkfd.h" /** * struct amdgpu_mn_node * * @it: interval node defining start-last of the affected address range * @bos: list of all BOs in the affected address range * * Manages all BOs which are affected of a certain range of address space. */struct amdgpu_mn_node {	struct interval_tree_node	it;	struct list_head		bos;}; /** * amdgpu_mn_destroy - destroy the HMM mirror * * @work: previously sheduled work item * * Lazy destroys the notifier from a work item */static void amdgpu_mn_destroy(struct work_struct *work){	struct amdgpu_mn *amn = container_of(work, struct amdgpu_mn, work);	struct amdgpu_device *adev = amn->adev;	struct amdgpu_mn_node *node, *next_node;	struct amdgpu_bo *bo, *next_bo; 	mutex_lock(&adev->mn_lock);	down_write(&amn->lock);	hash_del(&amn->node);	rbtree_postorder_for_each_entry_safe(node, next_node,					     &amn->objects.rb_root, it.rb) {		list_for_each_entry_safe(bo, next_bo, &node->bos, mn_list) {			bo->mn = NULL;			list_del_init(&bo->mn_list);		}		kfree(node);	}	up_write(&amn->lock);	mutex_unlock(&adev->mn_lock); 	hmm_mirror_unregister(&amn->mirror);	kfree(amn);} /** * amdgpu_hmm_mirror_release - callback to notify about mm destruction * * @mirror: the HMM mirror (mm) this callback is about * * Shedule a work item to lazy destroy HMM mirror. */static void amdgpu_hmm_mirror_release(struct hmm_mirror *mirror){	struct amdgpu_mn *amn = container_of(mirror, struct amdgpu_mn, mirror); 	INIT_WORK(&amn->work, amdgpu_mn_destroy);	schedule_work(&amn->work);} /** * amdgpu_mn_lock - take the write side lock for this notifier * * @mn: our notifier */void amdgpu_mn_lock(struct amdgpu_mn *mn){	if (mn)		down_write(&mn->lock);} /** * amdgpu_mn_unlock - drop the write side lock for this notifier * * @mn: our notifier */void amdgpu_mn_unlock(struct amdgpu_mn *mn){	if (mn)		up_write(&mn->lock);} /** * amdgpu_mn_read_lock - take the read side lock for this notifier * * @amn: our notifier */static int amdgpu_mn_read_lock(struct amdgpu_mn *amn, bool blockable){	if (blockable)		down_read(&amn->lock);	else if (!down_read_trylock(&amn->lock))		return -EAGAIN; 	return 0;} /** * amdgpu_mn_read_unlock - drop the read side lock for this notifier * * @amn: our notifier */static void amdgpu_mn_read_unlock(struct amdgpu_mn *amn){	up_read(&amn->lock);} /** * amdgpu_mn_invalidate_node - unmap all BOs of a node * * @node: the node with the BOs to unmap * @start: start of address range affected * @end: end of address range affected * * Block for operations on BOs to finish and mark pages as accessed and * potentially dirty. */static void amdgpu_mn_invalidate_node(struct amdgpu_mn_node *node,				      unsigned long start,				      unsigned long end){	struct amdgpu_bo *bo;	long r; 	list_for_each_entry(bo, &node->bos, mn_list) { 		if (!amdgpu_ttm_tt_affect_userptr(bo->tbo.ttm, start, end))			continue; 		r = reservation_object_wait_timeout_rcu(bo->tbo.resv,			true, false, MAX_SCHEDULE_TIMEOUT);		if (r <= 0)			DRM_ERROR("(%ld) failed to wait for user bo\n", r);	}} /** * amdgpu_mn_sync_pagetables_gfx - callback to notify about mm change * * @mirror: the hmm_mirror (mm) is about to update * @update: the update start, end address * * Block for operations on BOs to finish and mark pages as accessed and * potentially dirty. */static int amdgpu_mn_sync_pagetables_gfx(struct hmm_mirror *mirror,			const struct hmm_update *update){	struct amdgpu_mn *amn = container_of(mirror, struct amdgpu_mn, mirror);	unsigned long start = update->start;	unsigned long end = update->end;	bool blockable = update->blockable;	struct interval_tree_node *it; 	/* notification is exclusive, but interval is inclusive */	end -= 1; 	/* TODO we should be able to split locking for interval tree and	 * amdgpu_mn_invalidate_node	 */	if (amdgpu_mn_read_lock(amn, blockable))		return -EAGAIN; 	it = interval_tree_iter_first(&amn->objects, start, end);	while (it) {		struct amdgpu_mn_node *node; 		if (!blockable) {			amdgpu_mn_read_unlock(amn);			return -EAGAIN;		} 		node = container_of(it, struct amdgpu_mn_node, it);		it = interval_tree_iter_next(it, start, end); 		amdgpu_mn_invalidate_node(node, start, end);	} 	amdgpu_mn_read_unlock(amn); 	return 0;} /** * amdgpu_mn_sync_pagetables_hsa - callback to notify about mm change * * @mirror: the hmm_mirror (mm) is about to update * @update: the update start, end address * * We temporarily evict all BOs between start and end. This * necessitates evicting all user-mode queues of the process. The BOs * are restorted in amdgpu_mn_invalidate_range_end_hsa. */static int amdgpu_mn_sync_pagetables_hsa(struct hmm_mirror *mirror,			const struct hmm_update *update){	struct amdgpu_mn *amn = container_of(mirror, struct amdgpu_mn, mirror);	unsigned long start = update->start;	unsigned long end = update->end;	bool blockable = update->blockable;	struct interval_tree_node *it; 	/* notification is exclusive, but interval is inclusive */	end -= 1; 	if (amdgpu_mn_read_lock(amn, blockable))		return -EAGAIN; 	it = interval_tree_iter_first(&amn->objects, start, end);	while (it) {		struct amdgpu_mn_node *node;		struct amdgpu_bo *bo; 		if (!blockable) {			amdgpu_mn_read_unlock(amn);			return -EAGAIN;		} 		node = container_of(it, struct amdgpu_mn_node, it);		it = interval_tree_iter_next(it, start, end); 		list_for_each_entry(bo, &node->bos, mn_list) {			struct kgd_mem *mem = bo->kfd_bo; 			if (amdgpu_ttm_tt_affect_userptr(bo->tbo.ttm,							 start, end))				amdgpu_amdkfd_evict_userptr(mem, amn->mm);		}	} 	amdgpu_mn_read_unlock(amn); 	return 0;} /* Low bits of any reasonable mm pointer will be unused due to struct * alignment. Use these bits to make a unique key from the mm pointer * and notifier type. */#define AMDGPU_MN_KEY(mm, type) ((unsigned long)(mm) + (type)) static struct hmm_mirror_ops amdgpu_hmm_mirror_ops[] = {	[AMDGPU_MN_TYPE_GFX] = {		.sync_cpu_device_pagetables = amdgpu_mn_sync_pagetables_gfx,		.release = amdgpu_hmm_mirror_release	},	[AMDGPU_MN_TYPE_HSA] = {		.sync_cpu_device_pagetables = amdgpu_mn_sync_pagetables_hsa,		.release = amdgpu_hmm_mirror_release	},}; /** * amdgpu_mn_get - create HMM mirror context * * @adev: amdgpu device pointer * @type: type of MMU notifier context * * Creates a HMM mirror context for current->mm. */struct amdgpu_mn *amdgpu_mn_get(struct amdgpu_device *adev,				enum amdgpu_mn_type type){	struct mm_struct *mm = current->mm;	struct amdgpu_mn *amn;	unsigned long key = AMDGPU_MN_KEY(mm, type);	int r; 	mutex_lock(&adev->mn_lock);	if (down_write_killable(&mm->mmap_sem)) {		mutex_unlock(&adev->mn_lock);		return ERR_PTR(-EINTR);	} 	hash_for_each_possible(adev->mn_hash, amn, node, key)		if (AMDGPU_MN_KEY(amn->mm, amn->type) == key)			goto release_locks; 	amn = kzalloc(sizeof(*amn), GFP_KERNEL);	if (!amn) {		amn = ERR_PTR(-ENOMEM);		goto release_locks;	} 	amn->adev = adev;	amn->mm = mm;	init_rwsem(&amn->lock);	amn->type = type;	amn->objects = RB_ROOT_CACHED; 	amn->mirror.ops = &amdgpu_hmm_mirror_ops[type];	r = hmm_mirror_register(&amn->mirror, mm);	if (r)		goto free_amn; 	hash_add(adev->mn_hash, &amn->node, AMDGPU_MN_KEY(mm, type)); release_locks:	up_write(&mm->mmap_sem);	mutex_unlock(&adev->mn_lock); 	return amn; free_amn:	up_write(&mm->mmap_sem);	mutex_unlock(&adev->mn_lock);	kfree(amn); 	return ERR_PTR(r);} /** * amdgpu_mn_register - register a BO for notifier updates * * @bo: amdgpu buffer object * @addr: userptr addr we should monitor * * Registers an HMM mirror for the given BO at the specified address. * Returns 0 on success, -ERRNO if anything goes wrong. */int amdgpu_mn_register(struct amdgpu_bo *bo, unsigned long addr){	unsigned long end = addr + amdgpu_bo_size(bo) - 1;	struct amdgpu_device *adev = amdgpu_ttm_adev(bo->tbo.bdev);	enum amdgpu_mn_type type =		bo->kfd_bo ? AMDGPU_MN_TYPE_HSA : AMDGPU_MN_TYPE_GFX;	struct amdgpu_mn *amn;	struct amdgpu_mn_node *node = NULL, *new_node;	struct list_head bos;	struct interval_tree_node *it; 	amn = amdgpu_mn_get(adev, type);	if (IS_ERR(amn))		return PTR_ERR(amn); 	new_node = kmalloc(sizeof(*new_node), GFP_KERNEL);	if (!new_node)		return -ENOMEM; 	INIT_LIST_HEAD(&bos); 	down_write(&amn->lock); 	while ((it = interval_tree_iter_first(&amn->objects, addr, end))) {		kfree(node);		node = container_of(it, struct amdgpu_mn_node, it);		interval_tree_remove(&node->it, &amn->objects);		addr = min(it->start, addr);		end = max(it->last, end);		list_splice(&node->bos, &bos);	} 	if (!node)		node = new_node;	else		kfree(new_node); 	bo->mn = amn; 	node->it.start = addr;	node->it.last = end;	INIT_LIST_HEAD(&node->bos);	list_splice(&bos, &node->bos);	list_add(&bo->mn_list, &node->bos); 	interval_tree_insert(&node->it, &amn->objects); 	up_write(&amn->lock); 	return 0;} /** * amdgpu_mn_unregister - unregister a BO for HMM mirror updates * * @bo: amdgpu buffer object * * Remove any registration of HMM mirror updates from the buffer object. */void amdgpu_mn_unregister(struct amdgpu_bo *bo){	struct amdgpu_device *adev = amdgpu_ttm_adev(bo->tbo.bdev);	struct amdgpu_mn *amn;	struct list_head *head; 	mutex_lock(&adev->mn_lock); 	amn = bo->mn;	if (amn == NULL) {		mutex_unlock(&adev->mn_lock);		return;	} 	down_write(&amn->lock); 	/* save the next list entry for later */	head = bo->mn_list.next; 	bo->mn = NULL;	list_del_init(&bo->mn_list); 	if (list_empty(head)) {		struct amdgpu_mn_node *node; 		node = container_of(head, struct amdgpu_mn_node, bos);		interval_tree_remove(&node->it, &amn->objects);		kfree(node);	} 	up_write(&amn->lock);	mutex_unlock(&adev->mn_lock);} /* flags used by HMM internal, not related to CPU/GPU PTE flags */static const uint64_t hmm_range_flags[HMM_PFN_FLAG_MAX] = {		(1 << 0), /* HMM_PFN_VALID */		(1 << 1), /* HMM_PFN_WRITE */		0 /* HMM_PFN_DEVICE_PRIVATE */}; static const uint64_t hmm_range_values[HMM_PFN_VALUE_MAX] = {		0xfffffffffffffffeUL, /* HMM_PFN_ERROR */		0, /* HMM_PFN_NONE */		0xfffffffffffffffcUL /* HMM_PFN_SPECIAL */}; void amdgpu_hmm_init_range(struct hmm_range *range){	if (range) {		range->flags = hmm_range_flags;		range->values = hmm_range_values;		range->pfn_shift = PAGE_SHIFT;		INIT_LIST_HEAD(&range->list);	}}