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author | Christian König <christian.koenig@amd.com> | 2019-08-11 10:06:32 +0200 |
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committer | Christian König <christian.koenig@amd.com> | 2019-08-13 09:09:30 +0200 |
commit | 52791eeec1d9f4a7e7fe08aaba0b1553149d93bc (patch) | |
tree | ea1ff9cb7040e20e2cedad4ca8f7d2994ce3d0a8 /drivers/dma-buf/reservation.c | |
parent | 5d344f58da760b226562e7d5199fb73294eb93fa (diff) | |
download | linux-52791eeec1d9f4a7e7fe08aaba0b1553149d93bc.tar.bz2 |
dma-buf: rename reservation_object to dma_resv
Be more consistent with the naming of the other DMA-buf objects.
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/323401/
Diffstat (limited to 'drivers/dma-buf/reservation.c')
-rw-r--r-- | drivers/dma-buf/reservation.c | 610 |
1 files changed, 0 insertions, 610 deletions
diff --git a/drivers/dma-buf/reservation.c b/drivers/dma-buf/reservation.c deleted file mode 100644 index f7f4a0858c2a..000000000000 --- a/drivers/dma-buf/reservation.c +++ /dev/null @@ -1,610 +0,0 @@ -/* - * Copyright (C) 2012-2014 Canonical Ltd (Maarten Lankhorst) - * - * Based on bo.c which bears the following copyright notice, - * but is dual licensed: - * - * Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA - * 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 above copyright notice and this permission notice (including the - * next paragraph) shall be included in all copies or substantial portions - * of the Software. - * - * 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. - * - **************************************************************************/ -/* - * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com> - */ - -#include <linux/reservation.h> -#include <linux/export.h> - -/** - * DOC: Reservation Object Overview - * - * The reservation object provides a mechanism to manage shared and - * exclusive fences associated with a buffer. A reservation object - * can have attached one exclusive fence (normally associated with - * write operations) or N shared fences (read operations). The RCU - * mechanism is used to protect read access to fences from locked - * write-side updates. - */ - -DEFINE_WD_CLASS(reservation_ww_class); -EXPORT_SYMBOL(reservation_ww_class); - -/** - * reservation_object_list_alloc - allocate fence list - * @shared_max: number of fences we need space for - * - * Allocate a new reservation_object_list and make sure to correctly initialize - * shared_max. - */ -static struct reservation_object_list * -reservation_object_list_alloc(unsigned int shared_max) -{ - struct reservation_object_list *list; - - list = kmalloc(offsetof(typeof(*list), shared[shared_max]), GFP_KERNEL); - if (!list) - return NULL; - - list->shared_max = (ksize(list) - offsetof(typeof(*list), shared)) / - sizeof(*list->shared); - - return list; -} - -/** - * reservation_object_list_free - free fence list - * @list: list to free - * - * Free a reservation_object_list and make sure to drop all references. - */ -static void reservation_object_list_free(struct reservation_object_list *list) -{ - unsigned int i; - - if (!list) - return; - - for (i = 0; i < list->shared_count; ++i) - dma_fence_put(rcu_dereference_protected(list->shared[i], true)); - - kfree_rcu(list, rcu); -} - -/** - * reservation_object_init - initialize a reservation object - * @obj: the reservation object - */ -void reservation_object_init(struct reservation_object *obj) -{ - ww_mutex_init(&obj->lock, &reservation_ww_class); - RCU_INIT_POINTER(obj->fence, NULL); - RCU_INIT_POINTER(obj->fence_excl, NULL); -} -EXPORT_SYMBOL(reservation_object_init); - -/** - * reservation_object_fini - destroys a reservation object - * @obj: the reservation object - */ -void reservation_object_fini(struct reservation_object *obj) -{ - struct reservation_object_list *fobj; - struct dma_fence *excl; - - /* - * This object should be dead and all references must have - * been released to it, so no need to be protected with rcu. - */ - excl = rcu_dereference_protected(obj->fence_excl, 1); - if (excl) - dma_fence_put(excl); - - fobj = rcu_dereference_protected(obj->fence, 1); - reservation_object_list_free(fobj); - ww_mutex_destroy(&obj->lock); -} -EXPORT_SYMBOL(reservation_object_fini); - -/** - * reservation_object_reserve_shared - Reserve space to add shared fences to - * a reservation_object. - * @obj: reservation object - * @num_fences: number of fences we want to add - * - * Should be called before reservation_object_add_shared_fence(). Must - * be called with obj->lock held. - * - * RETURNS - * Zero for success, or -errno - */ -int reservation_object_reserve_shared(struct reservation_object *obj, - unsigned int num_fences) -{ - struct reservation_object_list *old, *new; - unsigned int i, j, k, max; - - reservation_object_assert_held(obj); - - old = reservation_object_get_list(obj); - - if (old && old->shared_max) { - if ((old->shared_count + num_fences) <= old->shared_max) - return 0; - else - max = max(old->shared_count + num_fences, - old->shared_max * 2); - } else { - max = 4; - } - - new = reservation_object_list_alloc(max); - if (!new) - return -ENOMEM; - - /* - * no need to bump fence refcounts, rcu_read access - * requires the use of kref_get_unless_zero, and the - * references from the old struct are carried over to - * the new. - */ - for (i = 0, j = 0, k = max; i < (old ? old->shared_count : 0); ++i) { - struct dma_fence *fence; - - fence = rcu_dereference_protected(old->shared[i], - reservation_object_held(obj)); - if (dma_fence_is_signaled(fence)) - RCU_INIT_POINTER(new->shared[--k], fence); - else - RCU_INIT_POINTER(new->shared[j++], fence); - } - new->shared_count = j; - - /* - * We are not changing the effective set of fences here so can - * merely update the pointer to the new array; both existing - * readers and new readers will see exactly the same set of - * active (unsignaled) shared fences. Individual fences and the - * old array are protected by RCU and so will not vanish under - * the gaze of the rcu_read_lock() readers. - */ - rcu_assign_pointer(obj->fence, new); - - if (!old) - return 0; - - /* Drop the references to the signaled fences */ - for (i = k; i < max; ++i) { - struct dma_fence *fence; - - fence = rcu_dereference_protected(new->shared[i], - reservation_object_held(obj)); - dma_fence_put(fence); - } - kfree_rcu(old, rcu); - - return 0; -} -EXPORT_SYMBOL(reservation_object_reserve_shared); - -/** - * reservation_object_add_shared_fence - Add a fence to a shared slot - * @obj: the reservation object - * @fence: the shared fence to add - * - * Add a fence to a shared slot, obj->lock must be held, and - * reservation_object_reserve_shared() has been called. - */ -void reservation_object_add_shared_fence(struct reservation_object *obj, - struct dma_fence *fence) -{ - struct reservation_object_list *fobj; - struct dma_fence *old; - unsigned int i, count; - - dma_fence_get(fence); - - reservation_object_assert_held(obj); - - fobj = reservation_object_get_list(obj); - count = fobj->shared_count; - - for (i = 0; i < count; ++i) { - - old = rcu_dereference_protected(fobj->shared[i], - reservation_object_held(obj)); - if (old->context == fence->context || - dma_fence_is_signaled(old)) - goto replace; - } - - BUG_ON(fobj->shared_count >= fobj->shared_max); - old = NULL; - count++; - -replace: - RCU_INIT_POINTER(fobj->shared[i], fence); - /* pointer update must be visible before we extend the shared_count */ - smp_store_mb(fobj->shared_count, count); - dma_fence_put(old); -} -EXPORT_SYMBOL(reservation_object_add_shared_fence); - -/** - * reservation_object_add_excl_fence - Add an exclusive fence. - * @obj: the reservation object - * @fence: the shared fence to add - * - * Add a fence to the exclusive slot. The obj->lock must be held. - */ -void reservation_object_add_excl_fence(struct reservation_object *obj, - struct dma_fence *fence) -{ - struct dma_fence *old_fence = reservation_object_get_excl(obj); - struct reservation_object_list *old; - u32 i = 0; - - reservation_object_assert_held(obj); - - old = reservation_object_get_list(obj); - if (old) - i = old->shared_count; - - if (fence) - dma_fence_get(fence); - - preempt_disable(); - rcu_assign_pointer(obj->fence_excl, fence); - /* pointer update must be visible before we modify the shared_count */ - if (old) - smp_store_mb(old->shared_count, 0); - preempt_enable(); - - /* inplace update, no shared fences */ - while (i--) - dma_fence_put(rcu_dereference_protected(old->shared[i], - reservation_object_held(obj))); - - dma_fence_put(old_fence); -} -EXPORT_SYMBOL(reservation_object_add_excl_fence); - -/** -* reservation_object_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 reservation_object_copy_fences(struct reservation_object *dst, - struct reservation_object *src) -{ - struct reservation_object_list *src_list, *dst_list; - struct dma_fence *old, *new; - unsigned int i, shared_count; - - reservation_object_assert_held(dst); - - rcu_read_lock(); - -retry: - reservation_object_fences(src, &new, &src_list, &shared_count); - if (shared_count) { - rcu_read_unlock(); - - dst_list = reservation_object_list_alloc(shared_count); - if (!dst_list) - return -ENOMEM; - - rcu_read_lock(); - reservation_object_fences(src, &new, &src_list, &shared_count); - if (!src_list || shared_count > dst_list->shared_max) { - kfree(dst_list); - goto retry; - } - - dst_list->shared_count = 0; - for (i = 0; i < shared_count; ++i) { - struct dma_fence *fence; - - fence = rcu_dereference(src_list->shared[i]); - if (test_bit(DMA_FENCE_FLAG_SIGNALED_BIT, - &fence->flags)) - continue; - - if (!dma_fence_get_rcu(fence)) { - reservation_object_list_free(dst_list); - goto retry; - } - - if (dma_fence_is_signaled(fence)) { - dma_fence_put(fence); - continue; - } - - rcu_assign_pointer(dst_list->shared[dst_list->shared_count++], fence); - } - } else { - dst_list = NULL; - } - - if (new && !dma_fence_get_rcu(new)) { - reservation_object_list_free(dst_list); - goto retry; - } - rcu_read_unlock(); - - src_list = reservation_object_get_list(dst); - old = reservation_object_get_excl(dst); - - preempt_disable(); - rcu_assign_pointer(dst->fence_excl, new); - rcu_assign_pointer(dst->fence, dst_list); - preempt_enable(); - - reservation_object_list_free(src_list); - dma_fence_put(old); - - return 0; -} -EXPORT_SYMBOL(reservation_object_copy_fences); - -/** - * reservation_object_get_fences_rcu - Get an object's shared and exclusive - * fences without update side lock held - * @obj: the reservation object - * @pfence_excl: the returned exclusive fence (or NULL) - * @pshared_count: the number of shared fences returned - * @pshared: the array of shared fence ptrs returned (array is krealloc'd to - * the required size, and must be freed by caller) - * - * Retrieve all fences from the reservation object. If the pointer for the - * exclusive fence is not specified the fence is put into the array of the - * shared fences as well. Returns either zero or -ENOMEM. - */ -int reservation_object_get_fences_rcu(struct reservation_object *obj, - struct dma_fence **pfence_excl, - unsigned *pshared_count, - struct dma_fence ***pshared) -{ - struct dma_fence **shared = NULL; - struct dma_fence *fence_excl; - unsigned int shared_count; - int ret = 1; - - do { - struct reservation_object_list *fobj; - unsigned int i; - size_t sz = 0; - - i = 0; - - rcu_read_lock(); - reservation_object_fences(obj, &fence_excl, &fobj, - &shared_count); - - if (fence_excl && !dma_fence_get_rcu(fence_excl)) - goto unlock; - - if (fobj) - sz += sizeof(*shared) * fobj->shared_max; - - if (!pfence_excl && fence_excl) - sz += sizeof(*shared); - - if (sz) { - struct dma_fence **nshared; - - nshared = krealloc(shared, sz, - GFP_NOWAIT | __GFP_NOWARN); - if (!nshared) { - rcu_read_unlock(); - - dma_fence_put(fence_excl); - fence_excl = NULL; - - nshared = krealloc(shared, sz, GFP_KERNEL); - if (nshared) { - shared = nshared; - continue; - } - - ret = -ENOMEM; - break; - } - shared = nshared; - for (i = 0; i < shared_count; ++i) { - shared[i] = rcu_dereference(fobj->shared[i]); - if (!dma_fence_get_rcu(shared[i])) - break; - } - } - - if (i != shared_count) { - while (i--) - dma_fence_put(shared[i]); - dma_fence_put(fence_excl); - goto unlock; - } - - ret = 0; -unlock: - rcu_read_unlock(); - } while (ret); - - if (pfence_excl) - *pfence_excl = fence_excl; - else if (fence_excl) - shared[++shared_count] = fence_excl; - - if (!shared_count) { - kfree(shared); - shared = NULL; - } - - *pshared_count = shared_count; - *pshared = shared; - return ret; -} -EXPORT_SYMBOL_GPL(reservation_object_get_fences_rcu); - -/** - * reservation_object_wait_timeout_rcu - Wait on reservation's objects - * shared and/or exclusive fences. - * @obj: the reservation object - * @wait_all: if true, wait on all fences, else wait on just exclusive fence - * @intr: if true, do interruptible wait - * @timeout: timeout value in jiffies or zero to return immediately - * - * RETURNS - * Returns -ERESTARTSYS if interrupted, 0 if the wait timed out, or - * greater than zer on success. - */ -long reservation_object_wait_timeout_rcu(struct reservation_object *obj, - bool wait_all, bool intr, - unsigned long timeout) -{ - struct reservation_object_list *fobj; - struct dma_fence *fence; - unsigned shared_count; - long ret = timeout ? timeout : 1; - int i; - -retry: - rcu_read_lock(); - i = -1; - - reservation_object_fences(obj, &fence, &fobj, &shared_count); - if (fence && !test_bit(DMA_FENCE_FLAG_SIGNALED_BIT, &fence->flags)) { - if (!dma_fence_get_rcu(fence)) - goto unlock_retry; - - if (dma_fence_is_signaled(fence)) { - dma_fence_put(fence); - fence = NULL; - } - - } else { - fence = NULL; - } - - if (wait_all) { - for (i = 0; !fence && i < shared_count; ++i) { - struct dma_fence *lfence = rcu_dereference(fobj->shared[i]); - - if (test_bit(DMA_FENCE_FLAG_SIGNALED_BIT, - &lfence->flags)) - continue; - - if (!dma_fence_get_rcu(lfence)) - goto unlock_retry; - - if (dma_fence_is_signaled(lfence)) { - dma_fence_put(lfence); - continue; - } - - fence = lfence; - break; - } - } - - rcu_read_unlock(); - if (fence) { - ret = dma_fence_wait_timeout(fence, intr, ret); - dma_fence_put(fence); - if (ret > 0 && wait_all && (i + 1 < shared_count)) - goto retry; - } - return ret; - -unlock_retry: - rcu_read_unlock(); - goto retry; -} -EXPORT_SYMBOL_GPL(reservation_object_wait_timeout_rcu); - - -static inline int -reservation_object_test_signaled_single(struct dma_fence *passed_fence) -{ - struct dma_fence *fence, *lfence = passed_fence; - int ret = 1; - - if (!test_bit(DMA_FENCE_FLAG_SIGNALED_BIT, &lfence->flags)) { - fence = dma_fence_get_rcu(lfence); - if (!fence) - return -1; - - ret = !!dma_fence_is_signaled(fence); - dma_fence_put(fence); - } - return ret; -} - -/** - * reservation_object_test_signaled_rcu - Test if a reservation object's - * fences have been signaled. - * @obj: the reservation object - * @test_all: if true, test all fences, otherwise only test the exclusive - * fence - * - * RETURNS - * true if all fences signaled, else false - */ -bool reservation_object_test_signaled_rcu(struct reservation_object *obj, - bool test_all) -{ - struct reservation_object_list *fobj; - struct dma_fence *fence_excl; - unsigned shared_count; - int ret; - - rcu_read_lock(); -retry: - ret = true; - - reservation_object_fences(obj, &fence_excl, &fobj, &shared_count); - if (test_all) { - unsigned i; - - for (i = 0; i < shared_count; ++i) { - struct dma_fence *fence = rcu_dereference(fobj->shared[i]); - - ret = reservation_object_test_signaled_single(fence); - if (ret < 0) - goto retry; - else if (!ret) - break; - } - } - - if (!shared_count && fence_excl) { - ret = reservation_object_test_signaled_single(fence_excl); - if (ret < 0) - goto retry; - } - - rcu_read_unlock(); - return ret; -} -EXPORT_SYMBOL_GPL(reservation_object_test_signaled_rcu); |