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authorLinus Torvalds <torvalds@linux-foundation.org>2020-06-02 15:04:15 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2020-06-02 15:04:15 -0700
commitfaa392181a0bd42c5478175cef601adeecdc91b6 (patch)
treee020e1142e34786676d0cd40f539bccdbb66099e /drivers/dma-buf
parentcfa3b8068b09f25037146bfd5eed041b78878bee (diff)
parent9ca1f474cea0edc14a1d7ec933e5472c0ff115d3 (diff)
Merge tag 'drm-next-2020-06-02' of git://anongit.freedesktop.org/drm/drm
Pull drm updates from Dave Airlie: "Highlights: - Core DRM had a lot of refactoring around managed drm resources to make drivers simpler. - Intel Tigerlake support is on by default - amdgpu now support p2p PCI buffer sharing and encrypted GPU memory Details: core: - uapi: error out EBUSY when existing master - uapi: rework SET/DROP MASTER permission handling - remove drm_pci.h - drm_pci* are now legacy - introduced managed DRM resources - subclassing support for drm_framebuffer - simple encoder helper - edid improvements - vblank + writeback documentation improved - drm/mm - optimise tree searches - port drivers to use devm_drm_dev_alloc dma-buf: - add flag for p2p buffer support mst: - ACT timeout improvements - remove drm_dp_mst_has_audio - don't use 2nd TX slot - spec recommends against it bridge: - dw-hdmi various improvements - chrontel ch7033 support - fix stack issues with old gcc hdmi: - add unpack function for drm infoframe fbdev: - misc fbdev driver fixes i915: - uapi: global sseu pinning - uapi: OA buffer polling - uapi: remove generated perf code - uapi: per-engine default property values in sysfs - Tigerlake GEN12 enabled. - Lots of gem refactoring - Tigerlake enablement patches - move to drm_device logging - Icelake gamma HW readout - push MST link retrain to hotplug work - bandwidth atomic helpers - ICL fixes - RPS/GT refactoring - Cherryview full-ppgtt support - i915 locking guidelines documented - require linear fb stride to be 512 multiple on gen9 - Tigerlake SAGV support amdgpu: - uapi: encrypted GPU memory handling - uapi: add MEM_SYNC IB flag - p2p dma-buf support - export VRAM dma-bufs - FRU chip access support - RAS/SR-IOV updates - Powerplay locking fixes - VCN DPG (powergating) enablement - GFX10 clockgating fixes - DC fixes - GPU reset fixes - navi SDMA fix - expose FP16 for modesetting - DP 1.4 compliance fixes - gfx10 soft recovery - Improved Critical Thermal Faults handling - resizable BAR on gmc10 amdkfd: - uapi: GWS resource management - track GPU memory per process - report PCI domain in topology radeon: - safe reg list generator fixes nouveau: - HD audio fixes on recent systems - vGPU detection (fail probe if we're on one, for now) - Interlaced mode fixes (mostly avoidance on Turing, which doesn't support it) - SVM improvements/fixes - NVIDIA format modifier support - Misc other fixes. adv7511: - HDMI SPDIF support ast: - allocate crtc state size - fix double assignment - fix suspend bochs: - drop connector register cirrus: - move to tiny drivers. exynos: - fix imported dma-buf mapping - enable runtime PM - fixes and cleanups mediatek: - DPI pin mode swap - config mipi_tx current/impedance lima: - devfreq + cooling device support - task handling improvements - runtime PM support pl111: - vexpress init improvements - fix module auto-load rcar-du: - DT bindings conversion to YAML - Planes zpos sanity check and fix - MAINTAINERS entry for LVDS panel driver mcde: - fix return value mgag200: - use managed config init stm: - read endpoints from DT vboxvideo: - use PCI managed functions - drop WC mtrr vkms: - enable cursor by default rockchip: - afbc support virtio: - various cleanups qxl: - fix cursor notify port hisilicon: - 128-byte stride alignment fix sun4i: - improved format handling" * tag 'drm-next-2020-06-02' of git://anongit.freedesktop.org/drm/drm: (1401 commits) drm/amd/display: Fix potential integer wraparound resulting in a hang drm/amd/display: drop cursor position check in atomic test drm/amdgpu: fix device attribute node create failed with multi gpu drm/nouveau: use correct conflicting framebuffer API drm/vblank: Fix -Wformat compile warnings on some arches drm/amdgpu: Sync with VM root BO when switching VM to CPU update mode drm/amd/display: Handle GPU reset for DC block drm/amdgpu: add apu flags (v2) drm/amd/powerpay: Disable gfxoff when setting manual mode on picasso and raven drm/amdgpu: fix pm sysfs node handling (v2) drm/amdgpu: move gpu_info parsing after common early init drm/amdgpu: move discovery gfx config fetching drm/nouveau/dispnv50: fix runtime pm imbalance on error drm/nouveau: fix runtime pm imbalance on error drm/nouveau: fix runtime pm imbalance on error drm/nouveau/debugfs: fix runtime pm imbalance on error drm/nouveau/nouveau/hmm: fix migrate zero page to GPU drm/nouveau/nouveau/hmm: fix nouveau_dmem_chunk allocations drm/nouveau/kms/nv50-: Share DP SST mode_valid() handling with MST drm/nouveau/kms/nv50-: Move 8BPC limit for MST into nv50_mstc_get_modes() ...
Diffstat (limited to 'drivers/dma-buf')
-rw-r--r--drivers/dma-buf/Makefile3
-rw-r--r--drivers/dma-buf/dma-buf.c2
-rw-r--r--drivers/dma-buf/dma-fence-chain.c10
-rw-r--r--drivers/dma-buf/dma-fence.c2
-rw-r--r--drivers/dma-buf/selftests.h1
-rw-r--r--drivers/dma-buf/st-dma-fence-chain.c715
6 files changed, 730 insertions, 3 deletions
diff --git a/drivers/dma-buf/Makefile b/drivers/dma-buf/Makefile
index 9c190026bfab..995e05f609ff 100644
--- a/drivers/dma-buf/Makefile
+++ b/drivers/dma-buf/Makefile
@@ -9,6 +9,7 @@ obj-$(CONFIG_UDMABUF) += udmabuf.o
dmabuf_selftests-y := \
selftest.o \
- st-dma-fence.o
+ st-dma-fence.o \
+ st-dma-fence-chain.o
obj-$(CONFIG_DMABUF_SELFTESTS) += dmabuf_selftests.o
diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c
index 07df88f2e305..01ce125f8e8d 100644
--- a/drivers/dma-buf/dma-buf.c
+++ b/drivers/dma-buf/dma-buf.c
@@ -691,6 +691,8 @@ dma_buf_dynamic_attach(struct dma_buf *dmabuf, struct device *dev,
attach->dev = dev;
attach->dmabuf = dmabuf;
+ if (importer_ops)
+ attach->peer2peer = importer_ops->allow_peer2peer;
attach->importer_ops = importer_ops;
attach->importer_priv = importer_priv;
diff --git a/drivers/dma-buf/dma-fence-chain.c b/drivers/dma-buf/dma-fence-chain.c
index 44a741677d25..c435bbba851c 100644
--- a/drivers/dma-buf/dma-fence-chain.c
+++ b/drivers/dma-buf/dma-fence-chain.c
@@ -62,7 +62,8 @@ struct dma_fence *dma_fence_chain_walk(struct dma_fence *fence)
replacement = NULL;
}
- tmp = cmpxchg((void **)&chain->prev, (void *)prev, (void *)replacement);
+ tmp = cmpxchg((struct dma_fence __force **)&chain->prev,
+ prev, replacement);
if (tmp == prev)
dma_fence_put(tmp);
else
@@ -98,6 +99,12 @@ int dma_fence_chain_find_seqno(struct dma_fence **pfence, uint64_t seqno)
return -EINVAL;
dma_fence_chain_for_each(*pfence, &chain->base) {
+ if ((*pfence)->seqno < seqno) { /* already signaled */
+ dma_fence_put(*pfence);
+ *pfence = NULL;
+ break;
+ }
+
if ((*pfence)->context != chain->base.context ||
to_dma_fence_chain(*pfence)->prev_seqno < seqno)
break;
@@ -221,6 +228,7 @@ EXPORT_SYMBOL(dma_fence_chain_ops);
* @chain: the chain node to initialize
* @prev: the previous fence
* @fence: the current fence
+ * @seqno: the sequence number (syncpt) of the fence within the chain
*
* Initialize a new chain node and either start a new chain or add the node to
* the existing chain of the previous fence.
diff --git a/drivers/dma-buf/dma-fence.c b/drivers/dma-buf/dma-fence.c
index 052a41e2451c..90edf2b281b0 100644
--- a/drivers/dma-buf/dma-fence.c
+++ b/drivers/dma-buf/dma-fence.c
@@ -106,7 +106,7 @@ EXPORT_SYMBOL(dma_fence_get_stub);
u64 dma_fence_context_alloc(unsigned num)
{
WARN_ON(!num);
- return atomic64_add_return(num, &dma_fence_context_counter) - num;
+ return atomic64_fetch_add(num, &dma_fence_context_counter);
}
EXPORT_SYMBOL(dma_fence_context_alloc);
diff --git a/drivers/dma-buf/selftests.h b/drivers/dma-buf/selftests.h
index 5320386f02e5..55918ef9adab 100644
--- a/drivers/dma-buf/selftests.h
+++ b/drivers/dma-buf/selftests.h
@@ -11,3 +11,4 @@
*/
selftest(sanitycheck, __sanitycheck__) /* keep first (igt selfcheck) */
selftest(dma_fence, dma_fence)
+selftest(dma_fence_chain, dma_fence_chain)
diff --git a/drivers/dma-buf/st-dma-fence-chain.c b/drivers/dma-buf/st-dma-fence-chain.c
new file mode 100644
index 000000000000..5d45ba7ba3cd
--- /dev/null
+++ b/drivers/dma-buf/st-dma-fence-chain.c
@@ -0,0 +1,715 @@
+// SPDX-License-Identifier: MIT
+
+/*
+ * Copyright © 2019 Intel Corporation
+ */
+
+#include <linux/delay.h>
+#include <linux/dma-fence.h>
+#include <linux/dma-fence-chain.h>
+#include <linux/kernel.h>
+#include <linux/kthread.h>
+#include <linux/mm.h>
+#include <linux/sched/signal.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/random.h>
+
+#include "selftest.h"
+
+#define CHAIN_SZ (4 << 10)
+
+static struct kmem_cache *slab_fences;
+
+static inline struct mock_fence {
+ struct dma_fence base;
+ spinlock_t lock;
+} *to_mock_fence(struct dma_fence *f) {
+ return container_of(f, struct mock_fence, base);
+}
+
+static const char *mock_name(struct dma_fence *f)
+{
+ return "mock";
+}
+
+static void mock_fence_release(struct dma_fence *f)
+{
+ kmem_cache_free(slab_fences, to_mock_fence(f));
+}
+
+static const struct dma_fence_ops mock_ops = {
+ .get_driver_name = mock_name,
+ .get_timeline_name = mock_name,
+ .release = mock_fence_release,
+};
+
+static struct dma_fence *mock_fence(void)
+{
+ struct mock_fence *f;
+
+ f = kmem_cache_alloc(slab_fences, GFP_KERNEL);
+ if (!f)
+ return NULL;
+
+ spin_lock_init(&f->lock);
+ dma_fence_init(&f->base, &mock_ops, &f->lock, 0, 0);
+
+ return &f->base;
+}
+
+static inline struct mock_chain {
+ struct dma_fence_chain base;
+} *to_mock_chain(struct dma_fence *f) {
+ return container_of(f, struct mock_chain, base.base);
+}
+
+static struct dma_fence *mock_chain(struct dma_fence *prev,
+ struct dma_fence *fence,
+ u64 seqno)
+{
+ struct mock_chain *f;
+
+ f = kmalloc(sizeof(*f), GFP_KERNEL);
+ if (!f)
+ return NULL;
+
+ dma_fence_chain_init(&f->base,
+ dma_fence_get(prev),
+ dma_fence_get(fence),
+ seqno);
+
+ return &f->base.base;
+}
+
+static int sanitycheck(void *arg)
+{
+ struct dma_fence *f, *chain;
+ int err = 0;
+
+ f = mock_fence();
+ if (!f)
+ return -ENOMEM;
+
+ chain = mock_chain(NULL, f, 1);
+ if (!chain)
+ err = -ENOMEM;
+
+ dma_fence_signal(f);
+ dma_fence_put(f);
+
+ dma_fence_put(chain);
+
+ return err;
+}
+
+struct fence_chains {
+ unsigned int chain_length;
+ struct dma_fence **fences;
+ struct dma_fence **chains;
+
+ struct dma_fence *tail;
+};
+
+static uint64_t seqno_inc(unsigned int i)
+{
+ return i + 1;
+}
+
+static int fence_chains_init(struct fence_chains *fc, unsigned int count,
+ uint64_t (*seqno_fn)(unsigned int))
+{
+ unsigned int i;
+ int err = 0;
+
+ fc->chains = kvmalloc_array(count, sizeof(*fc->chains),
+ GFP_KERNEL | __GFP_ZERO);
+ if (!fc->chains)
+ return -ENOMEM;
+
+ fc->fences = kvmalloc_array(count, sizeof(*fc->fences),
+ GFP_KERNEL | __GFP_ZERO);
+ if (!fc->fences) {
+ err = -ENOMEM;
+ goto err_chains;
+ }
+
+ fc->tail = NULL;
+ for (i = 0; i < count; i++) {
+ fc->fences[i] = mock_fence();
+ if (!fc->fences[i]) {
+ err = -ENOMEM;
+ goto unwind;
+ }
+
+ fc->chains[i] = mock_chain(fc->tail,
+ fc->fences[i],
+ seqno_fn(i));
+ if (!fc->chains[i]) {
+ err = -ENOMEM;
+ goto unwind;
+ }
+
+ fc->tail = fc->chains[i];
+ }
+
+ fc->chain_length = i;
+ return 0;
+
+unwind:
+ for (i = 0; i < count; i++) {
+ dma_fence_put(fc->fences[i]);
+ dma_fence_put(fc->chains[i]);
+ }
+ kvfree(fc->fences);
+err_chains:
+ kvfree(fc->chains);
+ return err;
+}
+
+static void fence_chains_fini(struct fence_chains *fc)
+{
+ unsigned int i;
+
+ for (i = 0; i < fc->chain_length; i++) {
+ dma_fence_signal(fc->fences[i]);
+ dma_fence_put(fc->fences[i]);
+ }
+ kvfree(fc->fences);
+
+ for (i = 0; i < fc->chain_length; i++)
+ dma_fence_put(fc->chains[i]);
+ kvfree(fc->chains);
+}
+
+static int find_seqno(void *arg)
+{
+ struct fence_chains fc;
+ struct dma_fence *fence;
+ int err;
+ int i;
+
+ err = fence_chains_init(&fc, 64, seqno_inc);
+ if (err)
+ return err;
+
+ fence = dma_fence_get(fc.tail);
+ err = dma_fence_chain_find_seqno(&fence, 0);
+ dma_fence_put(fence);
+ if (err) {
+ pr_err("Reported %d for find_seqno(0)!\n", err);
+ goto err;
+ }
+
+ for (i = 0; i < fc.chain_length; i++) {
+ fence = dma_fence_get(fc.tail);
+ err = dma_fence_chain_find_seqno(&fence, i + 1);
+ dma_fence_put(fence);
+ if (err) {
+ pr_err("Reported %d for find_seqno(%d:%d)!\n",
+ err, fc.chain_length + 1, i + 1);
+ goto err;
+ }
+ if (fence != fc.chains[i]) {
+ pr_err("Incorrect fence reported by find_seqno(%d:%d)\n",
+ fc.chain_length + 1, i + 1);
+ err = -EINVAL;
+ goto err;
+ }
+
+ dma_fence_get(fence);
+ err = dma_fence_chain_find_seqno(&fence, i + 1);
+ dma_fence_put(fence);
+ if (err) {
+ pr_err("Error reported for finding self\n");
+ goto err;
+ }
+ if (fence != fc.chains[i]) {
+ pr_err("Incorrect fence reported by find self\n");
+ err = -EINVAL;
+ goto err;
+ }
+
+ dma_fence_get(fence);
+ err = dma_fence_chain_find_seqno(&fence, i + 2);
+ dma_fence_put(fence);
+ if (!err) {
+ pr_err("Error not reported for future fence: find_seqno(%d:%d)!\n",
+ i + 1, i + 2);
+ err = -EINVAL;
+ goto err;
+ }
+
+ dma_fence_get(fence);
+ err = dma_fence_chain_find_seqno(&fence, i);
+ dma_fence_put(fence);
+ if (err) {
+ pr_err("Error reported for previous fence!\n");
+ goto err;
+ }
+ if (i > 0 && fence != fc.chains[i - 1]) {
+ pr_err("Incorrect fence reported by find_seqno(%d:%d)\n",
+ i + 1, i);
+ err = -EINVAL;
+ goto err;
+ }
+ }
+
+err:
+ fence_chains_fini(&fc);
+ return err;
+}
+
+static int find_signaled(void *arg)
+{
+ struct fence_chains fc;
+ struct dma_fence *fence;
+ int err;
+
+ err = fence_chains_init(&fc, 2, seqno_inc);
+ if (err)
+ return err;
+
+ dma_fence_signal(fc.fences[0]);
+
+ fence = dma_fence_get(fc.tail);
+ err = dma_fence_chain_find_seqno(&fence, 1);
+ dma_fence_put(fence);
+ if (err) {
+ pr_err("Reported %d for find_seqno()!\n", err);
+ goto err;
+ }
+
+ if (fence && fence != fc.chains[0]) {
+ pr_err("Incorrect chain-fence.seqno:%lld reported for completed seqno:1\n",
+ fence->seqno);
+
+ dma_fence_get(fence);
+ err = dma_fence_chain_find_seqno(&fence, 1);
+ dma_fence_put(fence);
+ if (err)
+ pr_err("Reported %d for finding self!\n", err);
+
+ err = -EINVAL;
+ }
+
+err:
+ fence_chains_fini(&fc);
+ return err;
+}
+
+static int find_out_of_order(void *arg)
+{
+ struct fence_chains fc;
+ struct dma_fence *fence;
+ int err;
+
+ err = fence_chains_init(&fc, 3, seqno_inc);
+ if (err)
+ return err;
+
+ dma_fence_signal(fc.fences[1]);
+
+ fence = dma_fence_get(fc.tail);
+ err = dma_fence_chain_find_seqno(&fence, 2);
+ dma_fence_put(fence);
+ if (err) {
+ pr_err("Reported %d for find_seqno()!\n", err);
+ goto err;
+ }
+
+ if (fence && fence != fc.chains[1]) {
+ pr_err("Incorrect chain-fence.seqno:%lld reported for completed seqno:2\n",
+ fence->seqno);
+
+ dma_fence_get(fence);
+ err = dma_fence_chain_find_seqno(&fence, 2);
+ dma_fence_put(fence);
+ if (err)
+ pr_err("Reported %d for finding self!\n", err);
+
+ err = -EINVAL;
+ }
+
+err:
+ fence_chains_fini(&fc);
+ return err;
+}
+
+static uint64_t seqno_inc2(unsigned int i)
+{
+ return 2 * i + 2;
+}
+
+static int find_gap(void *arg)
+{
+ struct fence_chains fc;
+ struct dma_fence *fence;
+ int err;
+ int i;
+
+ err = fence_chains_init(&fc, 64, seqno_inc2);
+ if (err)
+ return err;
+
+ for (i = 0; i < fc.chain_length; i++) {
+ fence = dma_fence_get(fc.tail);
+ err = dma_fence_chain_find_seqno(&fence, 2 * i + 1);
+ dma_fence_put(fence);
+ if (err) {
+ pr_err("Reported %d for find_seqno(%d:%d)!\n",
+ err, fc.chain_length + 1, 2 * i + 1);
+ goto err;
+ }
+ if (fence != fc.chains[i]) {
+ pr_err("Incorrect fence.seqno:%lld reported by find_seqno(%d:%d)\n",
+ fence->seqno,
+ fc.chain_length + 1,
+ 2 * i + 1);
+ err = -EINVAL;
+ goto err;
+ }
+
+ dma_fence_get(fence);
+ err = dma_fence_chain_find_seqno(&fence, 2 * i + 2);
+ dma_fence_put(fence);
+ if (err) {
+ pr_err("Error reported for finding self\n");
+ goto err;
+ }
+ if (fence != fc.chains[i]) {
+ pr_err("Incorrect fence reported by find self\n");
+ err = -EINVAL;
+ goto err;
+ }
+ }
+
+err:
+ fence_chains_fini(&fc);
+ return err;
+}
+
+struct find_race {
+ struct fence_chains fc;
+ atomic_t children;
+};
+
+static int __find_race(void *arg)
+{
+ struct find_race *data = arg;
+ int err = 0;
+
+ while (!kthread_should_stop()) {
+ struct dma_fence *fence = dma_fence_get(data->fc.tail);
+ int seqno;
+
+ seqno = prandom_u32_max(data->fc.chain_length) + 1;
+
+ err = dma_fence_chain_find_seqno(&fence, seqno);
+ if (err) {
+ pr_err("Failed to find fence seqno:%d\n",
+ seqno);
+ dma_fence_put(fence);
+ break;
+ }
+ if (!fence)
+ goto signal;
+
+ err = dma_fence_chain_find_seqno(&fence, seqno);
+ if (err) {
+ pr_err("Reported an invalid fence for find-self:%d\n",
+ seqno);
+ dma_fence_put(fence);
+ break;
+ }
+
+ if (fence->seqno < seqno) {
+ pr_err("Reported an earlier fence.seqno:%lld for seqno:%d\n",
+ fence->seqno, seqno);
+ err = -EINVAL;
+ dma_fence_put(fence);
+ break;
+ }
+
+ dma_fence_put(fence);
+
+signal:
+ seqno = prandom_u32_max(data->fc.chain_length - 1);
+ dma_fence_signal(data->fc.fences[seqno]);
+ cond_resched();
+ }
+
+ if (atomic_dec_and_test(&data->children))
+ wake_up_var(&data->children);
+ return err;
+}
+
+static int find_race(void *arg)
+{
+ struct find_race data;
+ int ncpus = num_online_cpus();
+ struct task_struct **threads;
+ unsigned long count;
+ int err;
+ int i;
+
+ err = fence_chains_init(&data.fc, CHAIN_SZ, seqno_inc);
+ if (err)
+ return err;
+
+ threads = kmalloc_array(ncpus, sizeof(*threads), GFP_KERNEL);
+ if (!threads) {
+ err = -ENOMEM;
+ goto err;
+ }
+
+ atomic_set(&data.children, 0);
+ for (i = 0; i < ncpus; i++) {
+ threads[i] = kthread_run(__find_race, &data, "dmabuf/%d", i);
+ if (IS_ERR(threads[i])) {
+ ncpus = i;
+ break;
+ }
+ atomic_inc(&data.children);
+ get_task_struct(threads[i]);
+ }
+
+ wait_var_event_timeout(&data.children,
+ !atomic_read(&data.children),
+ 5 * HZ);
+
+ for (i = 0; i < ncpus; i++) {
+ int ret;
+
+ ret = kthread_stop(threads[i]);
+ if (ret && !err)
+ err = ret;
+ put_task_struct(threads[i]);
+ }
+ kfree(threads);
+
+ count = 0;
+ for (i = 0; i < data.fc.chain_length; i++)
+ if (dma_fence_is_signaled(data.fc.fences[i]))
+ count++;
+ pr_info("Completed %lu cycles\n", count);
+
+err:
+ fence_chains_fini(&data.fc);
+ return err;
+}
+
+static int signal_forward(void *arg)
+{
+ struct fence_chains fc;
+ int err;
+ int i;
+
+ err = fence_chains_init(&fc, 64, seqno_inc);
+ if (err)
+ return err;
+
+ for (i = 0; i < fc.chain_length; i++) {
+ dma_fence_signal(fc.fences[i]);
+
+ if (!dma_fence_is_signaled(fc.chains[i])) {
+ pr_err("chain[%d] not signaled!\n", i);
+ err = -EINVAL;
+ goto err;
+ }
+
+ if (i + 1 < fc.chain_length &&
+ dma_fence_is_signaled(fc.chains[i + 1])) {
+ pr_err("chain[%d] is signaled!\n", i);
+ err = -EINVAL;
+ goto err;
+ }
+ }
+
+err:
+ fence_chains_fini(&fc);
+ return err;
+}
+
+static int signal_backward(void *arg)
+{
+ struct fence_chains fc;
+ int err;
+ int i;
+
+ err = fence_chains_init(&fc, 64, seqno_inc);
+ if (err)
+ return err;
+
+ for (i = fc.chain_length; i--; ) {
+ dma_fence_signal(fc.fences[i]);
+
+ if (i > 0 && dma_fence_is_signaled(fc.chains[i])) {
+ pr_err("chain[%d] is signaled!\n", i);
+ err = -EINVAL;
+ goto err;
+ }
+ }
+
+ for (i = 0; i < fc.chain_length; i++) {
+ if (!dma_fence_is_signaled(fc.chains[i])) {
+ pr_err("chain[%d] was not signaled!\n", i);
+ err = -EINVAL;
+ goto err;
+ }
+ }
+
+err:
+ fence_chains_fini(&fc);
+ return err;
+}
+
+static int __wait_fence_chains(void *arg)
+{
+ struct fence_chains *fc = arg;
+
+ if (dma_fence_wait(fc->tail, false))
+ return -EIO;
+
+ return 0;
+}
+
+static int wait_forward(void *arg)
+{
+ struct fence_chains fc;
+ struct task_struct *tsk;
+ int err;
+ int i;
+
+ err = fence_chains_init(&fc, CHAIN_SZ, seqno_inc);
+ if (err)
+ return err;
+
+ tsk = kthread_run(__wait_fence_chains, &fc, "dmabuf/wait");
+ if (IS_ERR(tsk)) {
+ err = PTR_ERR(tsk);
+ goto err;
+ }
+ get_task_struct(tsk);
+ yield_to(tsk, true);
+
+ for (i = 0; i < fc.chain_length; i++)
+ dma_fence_signal(fc.fences[i]);
+
+ err = kthread_stop(tsk);
+ put_task_struct(tsk);
+
+err:
+ fence_chains_fini(&fc);
+ return err;
+}
+
+static int wait_backward(void *arg)
+{
+ struct fence_chains fc;
+ struct task_struct *tsk;
+ int err;
+ int i;
+
+ err = fence_chains_init(&fc, CHAIN_SZ, seqno_inc);
+ if (err)
+ return err;
+
+ tsk = kthread_run(__wait_fence_chains, &fc, "dmabuf/wait");
+ if (IS_ERR(tsk)) {
+ err = PTR_ERR(tsk);
+ goto err;
+ }
+ get_task_struct(tsk);
+ yield_to(tsk, true);
+
+ for (i = fc.chain_length; i--; )
+ dma_fence_signal(fc.fences[i]);
+
+ err = kthread_stop(tsk);
+ put_task_struct(tsk);
+
+err:
+ fence_chains_fini(&fc);
+ return err;
+}
+
+static void randomise_fences(struct fence_chains *fc)
+{
+ unsigned int count = fc->chain_length;
+
+ /* Fisher-Yates shuffle courtesy of Knuth */
+ while (--count) {
+ unsigned int swp;
+
+ swp = prandom_u32_max(count + 1);
+ if (swp == count)
+ continue;
+
+ swap(fc->fences[count], fc->fences[swp]);
+ }
+}
+
+static int wait_random(void *arg)
+{
+ struct fence_chains fc;
+ struct task_struct *tsk;
+ int err;
+ int i;
+
+ err = fence_chains_init(&fc, CHAIN_SZ, seqno_inc);
+ if (err)
+ return err;
+
+ randomise_fences(&fc);
+
+ tsk = kthread_run(__wait_fence_chains, &fc, "dmabuf/wait");
+ if (IS_ERR(tsk)) {
+ err = PTR_ERR(tsk);
+ goto err;
+ }
+ get_task_struct(tsk);
+ yield_to(tsk, true);
+
+ for (i = 0; i < fc.chain_length; i++)
+ dma_fence_signal(fc.fences[i]);
+
+ err = kthread_stop(tsk);
+ put_task_struct(tsk);
+
+err:
+ fence_chains_fini(&fc);
+ return err;
+}
+
+int dma_fence_chain(void)
+{
+ static const struct subtest tests[] = {
+ SUBTEST(sanitycheck),
+ SUBTEST(find_seqno),
+ SUBTEST(find_signaled),
+ SUBTEST(find_out_of_order),
+ SUBTEST(find_gap),
+ SUBTEST(find_race),
+ SUBTEST(signal_forward),
+ SUBTEST(signal_backward),
+ SUBTEST(wait_forward),
+ SUBTEST(wait_backward),
+ SUBTEST(wait_random),
+ };
+ int ret;
+
+ pr_info("sizeof(dma_fence_chain)=%zu\n",
+ sizeof(struct dma_fence_chain));
+
+ slab_fences = KMEM_CACHE(mock_fence,
+ SLAB_TYPESAFE_BY_RCU |
+ SLAB_HWCACHE_ALIGN);
+ if (!slab_fences)
+ return -ENOMEM;
+
+ ret = subtests(tests, NULL);
+
+ kmem_cache_destroy(slab_fences);
+ return ret;
+}