From: Rob Clark robdclark@chromium.org
The motivation at this point is mainly native userspace mesa driver in a VM guest. The one remaining synchronous "hotpath" is buffer allocation, because guest needs to wait to know the bo's iova before it can start emitting cmdstream/state that references the new bo. By allocating the iova in the guest userspace, we no longer need to wait for a response from the host, but can just rely on the allocation request being processed before the cmdstream submission. Allocation faulures (OoM, etc) would just be treated as context-lost (ie. GL_GUILTY_CONTEXT_RESET) or subsequent allocations (or readpix, etc) can raise GL_OUT_OF_MEMORY.
Signed-off-by: Rob Clark robdclark@chromium.org --- drivers/gpu/drm/msm/adreno/adreno_gpu.c | 10 ++++++ drivers/gpu/drm/msm/msm_drv.c | 21 +++++++++++ drivers/gpu/drm/msm/msm_gem.c | 48 +++++++++++++++++++++++++ drivers/gpu/drm/msm/msm_gem.h | 8 +++++ drivers/gpu/drm/msm/msm_gem_vma.c | 2 ++ include/uapi/drm/msm_drm.h | 3 ++ 6 files changed, 92 insertions(+)
diff --git a/drivers/gpu/drm/msm/adreno/adreno_gpu.c b/drivers/gpu/drm/msm/adreno/adreno_gpu.c index 6385ab06632f..4caae0229518 100644 --- a/drivers/gpu/drm/msm/adreno/adreno_gpu.c +++ b/drivers/gpu/drm/msm/adreno/adreno_gpu.c @@ -281,6 +281,16 @@ int adreno_get_param(struct msm_gpu *gpu, struct msm_file_private *ctx, case MSM_PARAM_SUSPENDS: *value = gpu->suspend_count; return 0; + case MSM_PARAM_VA_START: + if (ctx->aspace == gpu->aspace) + return -EINVAL; + *value = ctx->aspace->va_start; + return 0; + case MSM_PARAM_VA_SIZE: + if (ctx->aspace == gpu->aspace) + return -EINVAL; + *value = ctx->aspace->va_size; + return 0; default: DBG("%s: invalid param: %u", gpu->name, param); return -EINVAL; diff --git a/drivers/gpu/drm/msm/msm_drv.c b/drivers/gpu/drm/msm/msm_drv.c index a5eed5738ac8..7394312cf075 100644 --- a/drivers/gpu/drm/msm/msm_drv.c +++ b/drivers/gpu/drm/msm/msm_drv.c @@ -719,6 +719,23 @@ static int msm_ioctl_gem_info_iova(struct drm_device *dev, return msm_gem_get_iova(obj, ctx->aspace, iova); }
+static int msm_ioctl_gem_info_set_iova(struct drm_device *dev, + struct drm_file *file, struct drm_gem_object *obj, + uint64_t iova) +{ + struct msm_drm_private *priv = dev->dev_private; + struct msm_file_private *ctx = file->driver_priv; + + if (!priv->gpu) + return -EINVAL; + + /* Only supported if per-process address space is supported: */ + if (priv->gpu->aspace == ctx->aspace) + return -EINVAL; + + return msm_gem_set_iova(obj, ctx->aspace, iova); +} + static int msm_ioctl_gem_info(struct drm_device *dev, void *data, struct drm_file *file) { @@ -733,6 +750,7 @@ static int msm_ioctl_gem_info(struct drm_device *dev, void *data, switch (args->info) { case MSM_INFO_GET_OFFSET: case MSM_INFO_GET_IOVA: + case MSM_INFO_SET_IOVA: /* value returned as immediate, not pointer, so len==0: */ if (args->len) return -EINVAL; @@ -757,6 +775,9 @@ static int msm_ioctl_gem_info(struct drm_device *dev, void *data, case MSM_INFO_GET_IOVA: ret = msm_ioctl_gem_info_iova(dev, file, obj, &args->value); break; + case MSM_INFO_SET_IOVA: + ret = msm_ioctl_gem_info_set_iova(dev, file, obj, args->value); + break; case MSM_INFO_SET_NAME: /* length check should leave room for terminating null: */ if (args->len >= sizeof(msm_obj->name)) { diff --git a/drivers/gpu/drm/msm/msm_gem.c b/drivers/gpu/drm/msm/msm_gem.c index bf4af17e2f1e..3122ba308f31 100644 --- a/drivers/gpu/drm/msm/msm_gem.c +++ b/drivers/gpu/drm/msm/msm_gem.c @@ -525,6 +525,54 @@ int msm_gem_get_iova(struct drm_gem_object *obj, return ret; }
+static int clear_iova(struct drm_gem_object *obj, + struct msm_gem_address_space *aspace) +{ + struct msm_gem_vma *vma = lookup_vma(obj, aspace); + + if (!vma) + return 0; + + if (vma->inuse) + return -EBUSY; + + msm_gem_purge_vma(vma->aspace, vma); + msm_gem_close_vma(vma->aspace, vma); + del_vma(vma); + + return 0; +} + +/* + * Get the requested iova but don't pin it. Fails if the requested iova is + * not available. Doesn't need a put because iovas are currently valid for + * the life of the object. + * + * Setting an iova of zero will clear the vma. + */ +int msm_gem_set_iova(struct drm_gem_object *obj, + struct msm_gem_address_space *aspace, uint64_t iova) +{ + int ret = 0; + + msm_gem_lock(obj); + if (!iova) { + ret = clear_iova(obj, aspace); + } else { + struct msm_gem_vma *vma; + vma = get_vma_locked(obj, aspace, iova, iova + obj->size); + if (IS_ERR(vma)) { + ret = PTR_ERR(vma); + } else if (GEM_WARN_ON(vma->iova != iova)) { + clear_iova(obj, aspace); + ret = -ENOSPC; + } + } + msm_gem_unlock(obj); + + return ret; +} + /* * Unpin a iova by updating the reference counts. The memory isn't actually * purged until something else (shrinker, mm_notifier, destroy, etc) decides diff --git a/drivers/gpu/drm/msm/msm_gem.h b/drivers/gpu/drm/msm/msm_gem.h index 38d66e1248b1..efa2e5c19f1e 100644 --- a/drivers/gpu/drm/msm/msm_gem.h +++ b/drivers/gpu/drm/msm/msm_gem.h @@ -38,6 +38,12 @@ struct msm_gem_address_space {
/* @faults: the number of GPU hangs associated with this address space */ int faults; + + /** @va_start: lowest possible address to allocate */ + uint64_t va_start; + + /** @va_size: the size of the address space (in bytes) */ + uint64_t va_size; };
struct msm_gem_address_space * @@ -144,6 +150,8 @@ struct msm_gem_vma *msm_gem_get_vma_locked(struct drm_gem_object *obj, struct msm_gem_address_space *aspace); int msm_gem_get_iova(struct drm_gem_object *obj, struct msm_gem_address_space *aspace, uint64_t *iova); +int msm_gem_set_iova(struct drm_gem_object *obj, + struct msm_gem_address_space *aspace, uint64_t iova); int msm_gem_get_and_pin_iova_range(struct drm_gem_object *obj, struct msm_gem_address_space *aspace, uint64_t *iova, u64 range_start, u64 range_end); diff --git a/drivers/gpu/drm/msm/msm_gem_vma.c b/drivers/gpu/drm/msm/msm_gem_vma.c index 6f9a402450f9..354f91aff573 100644 --- a/drivers/gpu/drm/msm/msm_gem_vma.c +++ b/drivers/gpu/drm/msm/msm_gem_vma.c @@ -182,6 +182,8 @@ msm_gem_address_space_create(struct msm_mmu *mmu, const char *name, spin_lock_init(&aspace->lock); aspace->name = name; aspace->mmu = mmu; + aspace->va_start = va_start; + aspace->va_size = size;
drm_mm_init(&aspace->mm, va_start, size);
diff --git a/include/uapi/drm/msm_drm.h b/include/uapi/drm/msm_drm.h index 794ad1948497..3c7b097c4e3d 100644 --- a/include/uapi/drm/msm_drm.h +++ b/include/uapi/drm/msm_drm.h @@ -84,6 +84,8 @@ struct drm_msm_timespec { #define MSM_PARAM_SYSPROF 0x0b /* WO: 1 preserves perfcntrs, 2 also disables suspend */ #define MSM_PARAM_COMM 0x0c /* WO: override for task->comm */ #define MSM_PARAM_CMDLINE 0x0d /* WO: override for task cmdline */ +#define MSM_PARAM_VA_START 0x0e /* RO: start of valid GPU iova range */ +#define MSM_PARAM_VA_SIZE 0x0f /* RO: size of valid GPU iova range (bytes) */
/* For backwards compat. The original support for preemption was based on * a single ring per priority level so # of priority levels equals the # @@ -135,6 +137,7 @@ struct drm_msm_gem_new { #define MSM_INFO_GET_IOVA 0x01 /* get iova, returned by value */ #define MSM_INFO_SET_NAME 0x02 /* set the debug name (by pointer) */ #define MSM_INFO_GET_NAME 0x03 /* get debug name, returned by pointer */ +#define MSM_INFO_SET_IOVA 0x04 /* set the iova, passed by value */
struct drm_msm_gem_info { __u32 handle; /* in */