Files
android_kernel_xiaomi_sm8450/drivers/gpu/drm/panfrost/panfrost_gem.c
Rob Herring 7282f7645d drm/panfrost: Implement per FD address spaces
Up until now, a single shared GPU address space was used. This is not
ideal as there's no protection between processes and doesn't work for
supporting the same GPU/CPU VA feature. Most importantly, this will
hopefully mitigate Alyssa's fear of WebGL, whatever that is.

Most of the changes here are moving struct drm_mm and struct
panfrost_mmu objects from the per device struct to the per FD struct.
The critical function is panfrost_mmu_as_get() which handles allocating
and switching the h/w address spaces.

There's 3 states an AS can be in: free, allocated, and in use. When a
job runs, it requests an address space and then marks it not in use when
job is complete(but stays assigned). The first time thru, we find a free
AS in the alloc_mask and assign the AS to the FD. Then the next time
thru, we most likely already have our AS and we just mark it in use with
a ref count. We need a ref count because we have multiple job slots. If
the job/FD doesn't have an AS assigned and there are no free ones, then
we pick an allocated one not in use from our LRU list and switch the AS
from the old FD to the new one.

Cc: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Steven Price <steven.price@arm.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Acked-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Reviewed-by: Steven Price <steven.price@arm.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190813150115.30338-1-robh@kernel.org
2019-08-19 11:34:57 -05:00

189 lines
4.7 KiB
C

// SPDX-License-Identifier: GPL-2.0
/* Copyright 2019 Linaro, Ltd, Rob Herring <robh@kernel.org> */
#include <linux/err.h>
#include <linux/slab.h>
#include <linux/dma-buf.h>
#include <linux/dma-mapping.h>
#include <drm/panfrost_drm.h>
#include "panfrost_device.h"
#include "panfrost_gem.h"
#include "panfrost_mmu.h"
/* Called DRM core on the last userspace/kernel unreference of the
* BO.
*/
static void panfrost_gem_free_object(struct drm_gem_object *obj)
{
struct panfrost_gem_object *bo = to_panfrost_bo(obj);
struct panfrost_device *pfdev = obj->dev->dev_private;
if (bo->sgts) {
int i;
int n_sgt = bo->base.base.size / SZ_2M;
for (i = 0; i < n_sgt; i++) {
if (bo->sgts[i].sgl) {
dma_unmap_sg(pfdev->dev, bo->sgts[i].sgl,
bo->sgts[i].nents, DMA_BIDIRECTIONAL);
sg_free_table(&bo->sgts[i]);
}
}
kfree(bo->sgts);
}
mutex_lock(&pfdev->shrinker_lock);
if (!list_empty(&bo->base.madv_list))
list_del(&bo->base.madv_list);
mutex_unlock(&pfdev->shrinker_lock);
drm_gem_shmem_free_object(obj);
}
static int panfrost_gem_open(struct drm_gem_object *obj, struct drm_file *file_priv)
{
int ret;
size_t size = obj->size;
u64 align;
struct panfrost_gem_object *bo = to_panfrost_bo(obj);
unsigned long color = bo->noexec ? PANFROST_BO_NOEXEC : 0;
struct panfrost_file_priv *priv = file_priv->driver_priv;
/*
* Executable buffers cannot cross a 16MB boundary as the program
* counter is 24-bits. We assume executable buffers will be less than
* 16MB and aligning executable buffers to their size will avoid
* crossing a 16MB boundary.
*/
if (!bo->noexec)
align = size >> PAGE_SHIFT;
else
align = size >= SZ_2M ? SZ_2M >> PAGE_SHIFT : 0;
bo->mmu = &priv->mmu;
spin_lock(&priv->mm_lock);
ret = drm_mm_insert_node_generic(&priv->mm, &bo->node,
size >> PAGE_SHIFT, align, color, 0);
if (ret)
goto out;
if (!bo->is_heap) {
ret = panfrost_mmu_map(bo);
if (ret)
drm_mm_remove_node(&bo->node);
}
out:
spin_unlock(&priv->mm_lock);
return ret;
}
static void panfrost_gem_close(struct drm_gem_object *obj, struct drm_file *file_priv)
{
struct panfrost_gem_object *bo = to_panfrost_bo(obj);
struct panfrost_file_priv *priv = file_priv->driver_priv;
if (bo->is_mapped)
panfrost_mmu_unmap(bo);
spin_lock(&priv->mm_lock);
if (drm_mm_node_allocated(&bo->node))
drm_mm_remove_node(&bo->node);
spin_unlock(&priv->mm_lock);
}
static int panfrost_gem_pin(struct drm_gem_object *obj)
{
if (to_panfrost_bo(obj)->is_heap)
return -EINVAL;
return drm_gem_shmem_pin(obj);
}
static const struct drm_gem_object_funcs panfrost_gem_funcs = {
.free = panfrost_gem_free_object,
.open = panfrost_gem_open,
.close = panfrost_gem_close,
.print_info = drm_gem_shmem_print_info,
.pin = panfrost_gem_pin,
.unpin = drm_gem_shmem_unpin,
.get_sg_table = drm_gem_shmem_get_sg_table,
.vmap = drm_gem_shmem_vmap,
.vunmap = drm_gem_shmem_vunmap,
.vm_ops = &drm_gem_shmem_vm_ops,
};
/**
* panfrost_gem_create_object - Implementation of driver->gem_create_object.
* @dev: DRM device
* @size: Size in bytes of the memory the object will reference
*
* This lets the GEM helpers allocate object structs for us, and keep
* our BO stats correct.
*/
struct drm_gem_object *panfrost_gem_create_object(struct drm_device *dev, size_t size)
{
struct panfrost_gem_object *obj;
obj = kzalloc(sizeof(*obj), GFP_KERNEL);
if (!obj)
return NULL;
obj->base.base.funcs = &panfrost_gem_funcs;
return &obj->base.base;
}
struct panfrost_gem_object *
panfrost_gem_create_with_handle(struct drm_file *file_priv,
struct drm_device *dev, size_t size,
u32 flags,
uint32_t *handle)
{
int ret;
struct drm_gem_shmem_object *shmem;
struct panfrost_gem_object *bo;
/* Round up heap allocations to 2MB to keep fault handling simple */
if (flags & PANFROST_BO_HEAP)
size = roundup(size, SZ_2M);
shmem = drm_gem_shmem_create(dev, size);
if (IS_ERR(shmem))
return ERR_CAST(shmem);
bo = to_panfrost_bo(&shmem->base);
bo->noexec = !!(flags & PANFROST_BO_NOEXEC);
bo->is_heap = !!(flags & PANFROST_BO_HEAP);
/*
* Allocate an id of idr table where the obj is registered
* and handle has the id what user can see.
*/
ret = drm_gem_handle_create(file_priv, &shmem->base, handle);
/* drop reference from allocate - handle holds it now. */
drm_gem_object_put_unlocked(&shmem->base);
if (ret)
return ERR_PTR(ret);
return bo;
}
struct drm_gem_object *
panfrost_gem_prime_import_sg_table(struct drm_device *dev,
struct dma_buf_attachment *attach,
struct sg_table *sgt)
{
struct drm_gem_object *obj;
struct panfrost_gem_object *bo;
obj = drm_gem_shmem_prime_import_sg_table(dev, attach, sgt);
if (IS_ERR(obj))
return ERR_CAST(obj);
bo = to_panfrost_bo(obj);
bo->noexec = true;
return obj;
}