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![xinhui pan](/assets/img/avatar_default.png)
Need get the new fence when we replace the old one.
Fixes: 047a1b877e
("dma-buf & drm/amdgpu: remove dma_resv workaround")
Signed-off-by: xinhui pan <xinhui.pan@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220707080241.20060-1-xinhui.pan@amd.com
Signed-off-by: Christian König <christian.koenig@amd.com>
773 lines
21 KiB
C
773 lines
21 KiB
C
// SPDX-License-Identifier: MIT
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/*
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* Copyright (C) 2012-2014 Canonical Ltd (Maarten Lankhorst)
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*
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* Based on bo.c which bears the following copyright notice,
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* but is dual licensed:
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*
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* Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA
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* All Rights Reserved.
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*
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* Permission is hereby granted, free of charge, to any person obtaining a
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* copy of this software and associated documentation files (the
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* "Software"), to deal in the Software without restriction, including
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* without limitation the rights to use, copy, modify, merge, publish,
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* distribute, sub license, and/or sell copies of the Software, and to
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* permit persons to whom the Software is furnished to do so, subject to
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* the following conditions:
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*
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* The above copyright notice and this permission notice (including the
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* next paragraph) shall be included in all copies or substantial portions
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* of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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* FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
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* THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
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* DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
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* OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
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* USE OR OTHER DEALINGS IN THE SOFTWARE.
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*
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**************************************************************************/
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/*
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* Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
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*/
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#include <linux/dma-resv.h>
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#include <linux/dma-fence-array.h>
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#include <linux/export.h>
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#include <linux/mm.h>
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#include <linux/sched/mm.h>
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#include <linux/mmu_notifier.h>
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#include <linux/seq_file.h>
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/**
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* DOC: Reservation Object Overview
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*
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* The reservation object provides a mechanism to manage a container of
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* dma_fence object associated with a resource. A reservation object
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* can have any number of fences attaches to it. Each fence carries an usage
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* parameter determining how the operation represented by the fence is using the
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* resource. The RCU mechanism is used to protect read access to fences from
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* locked write-side updates.
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*
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* See struct dma_resv for more details.
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*/
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DEFINE_WD_CLASS(reservation_ww_class);
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EXPORT_SYMBOL(reservation_ww_class);
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/* Mask for the lower fence pointer bits */
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#define DMA_RESV_LIST_MASK 0x3
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struct dma_resv_list {
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struct rcu_head rcu;
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u32 num_fences, max_fences;
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struct dma_fence __rcu *table[];
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};
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/* Extract the fence and usage flags from an RCU protected entry in the list. */
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static void dma_resv_list_entry(struct dma_resv_list *list, unsigned int index,
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struct dma_resv *resv, struct dma_fence **fence,
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enum dma_resv_usage *usage)
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{
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long tmp;
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tmp = (long)rcu_dereference_check(list->table[index],
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resv ? dma_resv_held(resv) : true);
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*fence = (struct dma_fence *)(tmp & ~DMA_RESV_LIST_MASK);
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if (usage)
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*usage = tmp & DMA_RESV_LIST_MASK;
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}
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/* Set the fence and usage flags at the specific index in the list. */
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static void dma_resv_list_set(struct dma_resv_list *list,
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unsigned int index,
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struct dma_fence *fence,
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enum dma_resv_usage usage)
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{
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long tmp = ((long)fence) | usage;
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RCU_INIT_POINTER(list->table[index], (struct dma_fence *)tmp);
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}
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/*
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* Allocate a new dma_resv_list and make sure to correctly initialize
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* max_fences.
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*/
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static struct dma_resv_list *dma_resv_list_alloc(unsigned int max_fences)
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{
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struct dma_resv_list *list;
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list = kmalloc(struct_size(list, table, max_fences), GFP_KERNEL);
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if (!list)
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return NULL;
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list->max_fences = (ksize(list) - offsetof(typeof(*list), table)) /
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sizeof(*list->table);
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return list;
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}
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/* Free a dma_resv_list and make sure to drop all references. */
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static void dma_resv_list_free(struct dma_resv_list *list)
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{
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unsigned int i;
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if (!list)
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return;
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for (i = 0; i < list->num_fences; ++i) {
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struct dma_fence *fence;
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dma_resv_list_entry(list, i, NULL, &fence, NULL);
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dma_fence_put(fence);
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}
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kfree_rcu(list, rcu);
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}
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/**
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* dma_resv_init - initialize a reservation object
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* @obj: the reservation object
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*/
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void dma_resv_init(struct dma_resv *obj)
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{
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ww_mutex_init(&obj->lock, &reservation_ww_class);
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RCU_INIT_POINTER(obj->fences, NULL);
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}
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EXPORT_SYMBOL(dma_resv_init);
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/**
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* dma_resv_fini - destroys a reservation object
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* @obj: the reservation object
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*/
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void dma_resv_fini(struct dma_resv *obj)
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{
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/*
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* This object should be dead and all references must have
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* been released to it, so no need to be protected with rcu.
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*/
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dma_resv_list_free(rcu_dereference_protected(obj->fences, true));
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ww_mutex_destroy(&obj->lock);
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}
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EXPORT_SYMBOL(dma_resv_fini);
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/* Dereference the fences while ensuring RCU rules */
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static inline struct dma_resv_list *dma_resv_fences_list(struct dma_resv *obj)
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{
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return rcu_dereference_check(obj->fences, dma_resv_held(obj));
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}
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/**
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* dma_resv_reserve_fences - Reserve space to add fences to a dma_resv object.
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* @obj: reservation object
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* @num_fences: number of fences we want to add
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*
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* Should be called before dma_resv_add_fence(). Must be called with @obj
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* locked through dma_resv_lock().
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*
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* Note that the preallocated slots need to be re-reserved if @obj is unlocked
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* at any time before calling dma_resv_add_fence(). This is validated when
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* CONFIG_DEBUG_MUTEXES is enabled.
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*
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* RETURNS
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* Zero for success, or -errno
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*/
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int dma_resv_reserve_fences(struct dma_resv *obj, unsigned int num_fences)
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{
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struct dma_resv_list *old, *new;
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unsigned int i, j, k, max;
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dma_resv_assert_held(obj);
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old = dma_resv_fences_list(obj);
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if (old && old->max_fences) {
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if ((old->num_fences + num_fences) <= old->max_fences)
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return 0;
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max = max(old->num_fences + num_fences, old->max_fences * 2);
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} else {
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max = max(4ul, roundup_pow_of_two(num_fences));
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}
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new = dma_resv_list_alloc(max);
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if (!new)
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return -ENOMEM;
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/*
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* no need to bump fence refcounts, rcu_read access
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* requires the use of kref_get_unless_zero, and the
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* references from the old struct are carried over to
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* the new.
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*/
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for (i = 0, j = 0, k = max; i < (old ? old->num_fences : 0); ++i) {
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enum dma_resv_usage usage;
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struct dma_fence *fence;
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dma_resv_list_entry(old, i, obj, &fence, &usage);
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if (dma_fence_is_signaled(fence))
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RCU_INIT_POINTER(new->table[--k], fence);
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else
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dma_resv_list_set(new, j++, fence, usage);
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}
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new->num_fences = j;
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/*
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* We are not changing the effective set of fences here so can
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* merely update the pointer to the new array; both existing
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* readers and new readers will see exactly the same set of
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* active (unsignaled) fences. Individual fences and the
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* old array are protected by RCU and so will not vanish under
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* the gaze of the rcu_read_lock() readers.
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*/
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rcu_assign_pointer(obj->fences, new);
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if (!old)
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return 0;
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/* Drop the references to the signaled fences */
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for (i = k; i < max; ++i) {
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struct dma_fence *fence;
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fence = rcu_dereference_protected(new->table[i],
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dma_resv_held(obj));
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dma_fence_put(fence);
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}
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kfree_rcu(old, rcu);
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return 0;
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}
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EXPORT_SYMBOL(dma_resv_reserve_fences);
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#ifdef CONFIG_DEBUG_MUTEXES
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/**
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* dma_resv_reset_max_fences - reset fences for debugging
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* @obj: the dma_resv object to reset
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*
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* Reset the number of pre-reserved fence slots to test that drivers do
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* correct slot allocation using dma_resv_reserve_fences(). See also
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* &dma_resv_list.max_fences.
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*/
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void dma_resv_reset_max_fences(struct dma_resv *obj)
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{
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struct dma_resv_list *fences = dma_resv_fences_list(obj);
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dma_resv_assert_held(obj);
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/* Test fence slot reservation */
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if (fences)
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fences->max_fences = fences->num_fences;
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}
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EXPORT_SYMBOL(dma_resv_reset_max_fences);
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#endif
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/**
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* dma_resv_add_fence - Add a fence to the dma_resv obj
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* @obj: the reservation object
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* @fence: the fence to add
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* @usage: how the fence is used, see enum dma_resv_usage
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*
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* Add a fence to a slot, @obj must be locked with dma_resv_lock(), and
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* dma_resv_reserve_fences() has been called.
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*
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* See also &dma_resv.fence for a discussion of the semantics.
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*/
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void dma_resv_add_fence(struct dma_resv *obj, struct dma_fence *fence,
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enum dma_resv_usage usage)
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{
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struct dma_resv_list *fobj;
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struct dma_fence *old;
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unsigned int i, count;
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dma_fence_get(fence);
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dma_resv_assert_held(obj);
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/* Drivers should not add containers here, instead add each fence
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* individually.
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*/
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WARN_ON(dma_fence_is_container(fence));
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fobj = dma_resv_fences_list(obj);
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count = fobj->num_fences;
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for (i = 0; i < count; ++i) {
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enum dma_resv_usage old_usage;
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dma_resv_list_entry(fobj, i, obj, &old, &old_usage);
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if ((old->context == fence->context && old_usage >= usage) ||
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dma_fence_is_signaled(old)) {
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dma_resv_list_set(fobj, i, fence, usage);
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dma_fence_put(old);
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return;
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}
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}
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BUG_ON(fobj->num_fences >= fobj->max_fences);
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count++;
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dma_resv_list_set(fobj, i, fence, usage);
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/* pointer update must be visible before we extend the num_fences */
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smp_store_mb(fobj->num_fences, count);
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}
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EXPORT_SYMBOL(dma_resv_add_fence);
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/**
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* dma_resv_replace_fences - replace fences in the dma_resv obj
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* @obj: the reservation object
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* @context: the context of the fences to replace
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* @replacement: the new fence to use instead
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* @usage: how the new fence is used, see enum dma_resv_usage
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*
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* Replace fences with a specified context with a new fence. Only valid if the
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* operation represented by the original fence has no longer access to the
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* resources represented by the dma_resv object when the new fence completes.
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*
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* And example for using this is replacing a preemption fence with a page table
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* update fence which makes the resource inaccessible.
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*/
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void dma_resv_replace_fences(struct dma_resv *obj, uint64_t context,
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struct dma_fence *replacement,
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enum dma_resv_usage usage)
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{
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struct dma_resv_list *list;
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unsigned int i;
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dma_resv_assert_held(obj);
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list = dma_resv_fences_list(obj);
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for (i = 0; list && i < list->num_fences; ++i) {
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struct dma_fence *old;
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dma_resv_list_entry(list, i, obj, &old, NULL);
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if (old->context != context)
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continue;
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dma_resv_list_set(list, i, dma_fence_get(replacement), usage);
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dma_fence_put(old);
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}
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}
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EXPORT_SYMBOL(dma_resv_replace_fences);
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/* Restart the unlocked iteration by initializing the cursor object. */
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static void dma_resv_iter_restart_unlocked(struct dma_resv_iter *cursor)
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{
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cursor->index = 0;
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cursor->num_fences = 0;
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cursor->fences = dma_resv_fences_list(cursor->obj);
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if (cursor->fences)
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cursor->num_fences = cursor->fences->num_fences;
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cursor->is_restarted = true;
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}
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/* Walk to the next not signaled fence and grab a reference to it */
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static void dma_resv_iter_walk_unlocked(struct dma_resv_iter *cursor)
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{
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if (!cursor->fences)
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return;
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do {
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/* Drop the reference from the previous round */
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dma_fence_put(cursor->fence);
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if (cursor->index >= cursor->num_fences) {
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cursor->fence = NULL;
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break;
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}
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dma_resv_list_entry(cursor->fences, cursor->index++,
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cursor->obj, &cursor->fence,
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&cursor->fence_usage);
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cursor->fence = dma_fence_get_rcu(cursor->fence);
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if (!cursor->fence) {
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dma_resv_iter_restart_unlocked(cursor);
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continue;
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}
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if (!dma_fence_is_signaled(cursor->fence) &&
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cursor->usage >= cursor->fence_usage)
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break;
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} while (true);
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}
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/**
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* dma_resv_iter_first_unlocked - first fence in an unlocked dma_resv obj.
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* @cursor: the cursor with the current position
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*
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* Subsequent fences are iterated with dma_resv_iter_next_unlocked().
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*
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* Beware that the iterator can be restarted. Code which accumulates statistics
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* or similar needs to check for this with dma_resv_iter_is_restarted(). For
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* this reason prefer the locked dma_resv_iter_first() whenver possible.
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*
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* Returns the first fence from an unlocked dma_resv obj.
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*/
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struct dma_fence *dma_resv_iter_first_unlocked(struct dma_resv_iter *cursor)
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{
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rcu_read_lock();
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do {
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dma_resv_iter_restart_unlocked(cursor);
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dma_resv_iter_walk_unlocked(cursor);
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} while (dma_resv_fences_list(cursor->obj) != cursor->fences);
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rcu_read_unlock();
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return cursor->fence;
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}
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EXPORT_SYMBOL(dma_resv_iter_first_unlocked);
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/**
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* dma_resv_iter_next_unlocked - next fence in an unlocked dma_resv obj.
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* @cursor: the cursor with the current position
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*
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* Beware that the iterator can be restarted. Code which accumulates statistics
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* or similar needs to check for this with dma_resv_iter_is_restarted(). For
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* this reason prefer the locked dma_resv_iter_next() whenver possible.
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*
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* Returns the next fence from an unlocked dma_resv obj.
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*/
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struct dma_fence *dma_resv_iter_next_unlocked(struct dma_resv_iter *cursor)
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{
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bool restart;
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rcu_read_lock();
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cursor->is_restarted = false;
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restart = dma_resv_fences_list(cursor->obj) != cursor->fences;
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do {
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if (restart)
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dma_resv_iter_restart_unlocked(cursor);
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dma_resv_iter_walk_unlocked(cursor);
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restart = true;
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} while (dma_resv_fences_list(cursor->obj) != cursor->fences);
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rcu_read_unlock();
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return cursor->fence;
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}
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EXPORT_SYMBOL(dma_resv_iter_next_unlocked);
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/**
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* dma_resv_iter_first - first fence from a locked dma_resv object
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* @cursor: cursor to record the current position
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*
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* Subsequent fences are iterated with dma_resv_iter_next_unlocked().
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*
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* Return the first fence in the dma_resv object while holding the
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* &dma_resv.lock.
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*/
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struct dma_fence *dma_resv_iter_first(struct dma_resv_iter *cursor)
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{
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struct dma_fence *fence;
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dma_resv_assert_held(cursor->obj);
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cursor->index = 0;
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cursor->fences = dma_resv_fences_list(cursor->obj);
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fence = dma_resv_iter_next(cursor);
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cursor->is_restarted = true;
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return fence;
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}
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EXPORT_SYMBOL_GPL(dma_resv_iter_first);
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/**
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* dma_resv_iter_next - next fence from a locked dma_resv object
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* @cursor: cursor to record the current position
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*
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* Return the next fences from the dma_resv object while holding the
|
|
* &dma_resv.lock.
|
|
*/
|
|
struct dma_fence *dma_resv_iter_next(struct dma_resv_iter *cursor)
|
|
{
|
|
struct dma_fence *fence;
|
|
|
|
dma_resv_assert_held(cursor->obj);
|
|
|
|
cursor->is_restarted = false;
|
|
|
|
do {
|
|
if (!cursor->fences ||
|
|
cursor->index >= cursor->fences->num_fences)
|
|
return NULL;
|
|
|
|
dma_resv_list_entry(cursor->fences, cursor->index++,
|
|
cursor->obj, &fence, &cursor->fence_usage);
|
|
} while (cursor->fence_usage > cursor->usage);
|
|
|
|
return fence;
|
|
}
|
|
EXPORT_SYMBOL_GPL(dma_resv_iter_next);
|
|
|
|
/**
|
|
* dma_resv_copy_fences - Copy all fences from src to dst.
|
|
* @dst: the destination reservation object
|
|
* @src: the source reservation object
|
|
*
|
|
* Copy all fences from src to dst. dst-lock must be held.
|
|
*/
|
|
int dma_resv_copy_fences(struct dma_resv *dst, struct dma_resv *src)
|
|
{
|
|
struct dma_resv_iter cursor;
|
|
struct dma_resv_list *list;
|
|
struct dma_fence *f;
|
|
|
|
dma_resv_assert_held(dst);
|
|
|
|
list = NULL;
|
|
|
|
dma_resv_iter_begin(&cursor, src, DMA_RESV_USAGE_BOOKKEEP);
|
|
dma_resv_for_each_fence_unlocked(&cursor, f) {
|
|
|
|
if (dma_resv_iter_is_restarted(&cursor)) {
|
|
dma_resv_list_free(list);
|
|
|
|
list = dma_resv_list_alloc(cursor.num_fences);
|
|
if (!list) {
|
|
dma_resv_iter_end(&cursor);
|
|
return -ENOMEM;
|
|
}
|
|
list->num_fences = 0;
|
|
}
|
|
|
|
dma_fence_get(f);
|
|
dma_resv_list_set(list, list->num_fences++, f,
|
|
dma_resv_iter_usage(&cursor));
|
|
}
|
|
dma_resv_iter_end(&cursor);
|
|
|
|
list = rcu_replace_pointer(dst->fences, list, dma_resv_held(dst));
|
|
dma_resv_list_free(list);
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL(dma_resv_copy_fences);
|
|
|
|
/**
|
|
* dma_resv_get_fences - Get an object's fences
|
|
* fences without update side lock held
|
|
* @obj: the reservation object
|
|
* @usage: controls which fences to include, see enum dma_resv_usage.
|
|
* @num_fences: the number of fences returned
|
|
* @fences: the array of fence ptrs returned (array is krealloc'd to the
|
|
* required size, and must be freed by caller)
|
|
*
|
|
* Retrieve all fences from the reservation object.
|
|
* Returns either zero or -ENOMEM.
|
|
*/
|
|
int dma_resv_get_fences(struct dma_resv *obj, enum dma_resv_usage usage,
|
|
unsigned int *num_fences, struct dma_fence ***fences)
|
|
{
|
|
struct dma_resv_iter cursor;
|
|
struct dma_fence *fence;
|
|
|
|
*num_fences = 0;
|
|
*fences = NULL;
|
|
|
|
dma_resv_iter_begin(&cursor, obj, usage);
|
|
dma_resv_for_each_fence_unlocked(&cursor, fence) {
|
|
|
|
if (dma_resv_iter_is_restarted(&cursor)) {
|
|
unsigned int count;
|
|
|
|
while (*num_fences)
|
|
dma_fence_put((*fences)[--(*num_fences)]);
|
|
|
|
count = cursor.num_fences + 1;
|
|
|
|
/* Eventually re-allocate the array */
|
|
*fences = krealloc_array(*fences, count,
|
|
sizeof(void *),
|
|
GFP_KERNEL);
|
|
if (count && !*fences) {
|
|
dma_resv_iter_end(&cursor);
|
|
return -ENOMEM;
|
|
}
|
|
}
|
|
|
|
(*fences)[(*num_fences)++] = dma_fence_get(fence);
|
|
}
|
|
dma_resv_iter_end(&cursor);
|
|
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(dma_resv_get_fences);
|
|
|
|
/**
|
|
* dma_resv_get_singleton - Get a single fence for all the fences
|
|
* @obj: the reservation object
|
|
* @usage: controls which fences to include, see enum dma_resv_usage.
|
|
* @fence: the resulting fence
|
|
*
|
|
* Get a single fence representing all the fences inside the resv object.
|
|
* Returns either 0 for success or -ENOMEM.
|
|
*
|
|
* Warning: This can't be used like this when adding the fence back to the resv
|
|
* object since that can lead to stack corruption when finalizing the
|
|
* dma_fence_array.
|
|
*
|
|
* Returns 0 on success and negative error values on failure.
|
|
*/
|
|
int dma_resv_get_singleton(struct dma_resv *obj, enum dma_resv_usage usage,
|
|
struct dma_fence **fence)
|
|
{
|
|
struct dma_fence_array *array;
|
|
struct dma_fence **fences;
|
|
unsigned count;
|
|
int r;
|
|
|
|
r = dma_resv_get_fences(obj, usage, &count, &fences);
|
|
if (r)
|
|
return r;
|
|
|
|
if (count == 0) {
|
|
*fence = NULL;
|
|
return 0;
|
|
}
|
|
|
|
if (count == 1) {
|
|
*fence = fences[0];
|
|
kfree(fences);
|
|
return 0;
|
|
}
|
|
|
|
array = dma_fence_array_create(count, fences,
|
|
dma_fence_context_alloc(1),
|
|
1, false);
|
|
if (!array) {
|
|
while (count--)
|
|
dma_fence_put(fences[count]);
|
|
kfree(fences);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
*fence = &array->base;
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(dma_resv_get_singleton);
|
|
|
|
/**
|
|
* dma_resv_wait_timeout - Wait on reservation's objects fences
|
|
* @obj: the reservation object
|
|
* @usage: controls which fences to include, see enum dma_resv_usage.
|
|
* @intr: if true, do interruptible wait
|
|
* @timeout: timeout value in jiffies or zero to return immediately
|
|
*
|
|
* Callers are not required to hold specific locks, but maybe hold
|
|
* dma_resv_lock() already
|
|
* RETURNS
|
|
* Returns -ERESTARTSYS if interrupted, 0 if the wait timed out, or
|
|
* greater than zer on success.
|
|
*/
|
|
long dma_resv_wait_timeout(struct dma_resv *obj, enum dma_resv_usage usage,
|
|
bool intr, unsigned long timeout)
|
|
{
|
|
long ret = timeout ? timeout : 1;
|
|
struct dma_resv_iter cursor;
|
|
struct dma_fence *fence;
|
|
|
|
dma_resv_iter_begin(&cursor, obj, usage);
|
|
dma_resv_for_each_fence_unlocked(&cursor, fence) {
|
|
|
|
ret = dma_fence_wait_timeout(fence, intr, ret);
|
|
if (ret <= 0) {
|
|
dma_resv_iter_end(&cursor);
|
|
return ret;
|
|
}
|
|
}
|
|
dma_resv_iter_end(&cursor);
|
|
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL_GPL(dma_resv_wait_timeout);
|
|
|
|
|
|
/**
|
|
* dma_resv_test_signaled - Test if a reservation object's fences have been
|
|
* signaled.
|
|
* @obj: the reservation object
|
|
* @usage: controls which fences to include, see enum dma_resv_usage.
|
|
*
|
|
* Callers are not required to hold specific locks, but maybe hold
|
|
* dma_resv_lock() already.
|
|
*
|
|
* RETURNS
|
|
*
|
|
* True if all fences signaled, else false.
|
|
*/
|
|
bool dma_resv_test_signaled(struct dma_resv *obj, enum dma_resv_usage usage)
|
|
{
|
|
struct dma_resv_iter cursor;
|
|
struct dma_fence *fence;
|
|
|
|
dma_resv_iter_begin(&cursor, obj, usage);
|
|
dma_resv_for_each_fence_unlocked(&cursor, fence) {
|
|
dma_resv_iter_end(&cursor);
|
|
return false;
|
|
}
|
|
dma_resv_iter_end(&cursor);
|
|
return true;
|
|
}
|
|
EXPORT_SYMBOL_GPL(dma_resv_test_signaled);
|
|
|
|
/**
|
|
* dma_resv_describe - Dump description of the resv object into seq_file
|
|
* @obj: the reservation object
|
|
* @seq: the seq_file to dump the description into
|
|
*
|
|
* Dump a textual description of the fences inside an dma_resv object into the
|
|
* seq_file.
|
|
*/
|
|
void dma_resv_describe(struct dma_resv *obj, struct seq_file *seq)
|
|
{
|
|
static const char *usage[] = { "kernel", "write", "read", "bookkeep" };
|
|
struct dma_resv_iter cursor;
|
|
struct dma_fence *fence;
|
|
|
|
dma_resv_for_each_fence(&cursor, obj, DMA_RESV_USAGE_READ, fence) {
|
|
seq_printf(seq, "\t%s fence:",
|
|
usage[dma_resv_iter_usage(&cursor)]);
|
|
dma_fence_describe(fence, seq);
|
|
}
|
|
}
|
|
EXPORT_SYMBOL_GPL(dma_resv_describe);
|
|
|
|
#if IS_ENABLED(CONFIG_LOCKDEP)
|
|
static int __init dma_resv_lockdep(void)
|
|
{
|
|
struct mm_struct *mm = mm_alloc();
|
|
struct ww_acquire_ctx ctx;
|
|
struct dma_resv obj;
|
|
struct address_space mapping;
|
|
int ret;
|
|
|
|
if (!mm)
|
|
return -ENOMEM;
|
|
|
|
dma_resv_init(&obj);
|
|
address_space_init_once(&mapping);
|
|
|
|
mmap_read_lock(mm);
|
|
ww_acquire_init(&ctx, &reservation_ww_class);
|
|
ret = dma_resv_lock(&obj, &ctx);
|
|
if (ret == -EDEADLK)
|
|
dma_resv_lock_slow(&obj, &ctx);
|
|
fs_reclaim_acquire(GFP_KERNEL);
|
|
/* for unmap_mapping_range on trylocked buffer objects in shrinkers */
|
|
i_mmap_lock_write(&mapping);
|
|
i_mmap_unlock_write(&mapping);
|
|
#ifdef CONFIG_MMU_NOTIFIER
|
|
lock_map_acquire(&__mmu_notifier_invalidate_range_start_map);
|
|
__dma_fence_might_wait();
|
|
lock_map_release(&__mmu_notifier_invalidate_range_start_map);
|
|
#else
|
|
__dma_fence_might_wait();
|
|
#endif
|
|
fs_reclaim_release(GFP_KERNEL);
|
|
ww_mutex_unlock(&obj.lock);
|
|
ww_acquire_fini(&ctx);
|
|
mmap_read_unlock(mm);
|
|
|
|
mmput(mm);
|
|
|
|
return 0;
|
|
}
|
|
subsys_initcall(dma_resv_lockdep);
|
|
#endif
|