diff --git a/drivers/gpu/drm/i915/gvt/aperture_gm.c b/drivers/gpu/drm/i915/gvt/aperture_gm.c index ca3d1925beda..7c9ec4f4f36c 100644 --- a/drivers/gpu/drm/i915/gvt/aperture_gm.c +++ b/drivers/gpu/drm/i915/gvt/aperture_gm.c @@ -173,8 +173,8 @@ static void free_vgpu_fence(struct intel_vgpu *vgpu) _clear_vgpu_fence(vgpu); for (i = 0; i < vgpu_fence_sz(vgpu); i++) { reg = vgpu->fence.regs[i]; - list_add_tail(®->link, - &dev_priv->mm.fence_list); + i915_unreserve_fence(reg); + vgpu->fence.regs[i] = NULL; } mutex_unlock(&dev_priv->drm.struct_mutex); @@ -187,24 +187,19 @@ static int alloc_vgpu_fence(struct intel_vgpu *vgpu) struct drm_i915_private *dev_priv = gvt->dev_priv; struct drm_i915_fence_reg *reg; int i; - struct list_head *pos, *q; intel_runtime_pm_get(dev_priv); /* Request fences from host */ mutex_lock(&dev_priv->drm.struct_mutex); - i = 0; - list_for_each_safe(pos, q, &dev_priv->mm.fence_list) { - reg = list_entry(pos, struct drm_i915_fence_reg, link); - if (reg->pin_count || reg->vma) - continue; - list_del(pos); + + for (i = 0; i < vgpu_fence_sz(vgpu); i++) { + reg = i915_reserve_fence(dev_priv); + if (IS_ERR(reg)) + goto out_free_fence; + vgpu->fence.regs[i] = reg; - if (++i == vgpu_fence_sz(vgpu)) - break; } - if (i != vgpu_fence_sz(vgpu)) - goto out_free_fence; _clear_vgpu_fence(vgpu); @@ -212,13 +207,14 @@ static int alloc_vgpu_fence(struct intel_vgpu *vgpu) intel_runtime_pm_put(dev_priv); return 0; out_free_fence: + gvt_vgpu_err("Failed to alloc fences\n"); /* Return fences to host, if fail */ for (i = 0; i < vgpu_fence_sz(vgpu); i++) { reg = vgpu->fence.regs[i]; if (!reg) continue; - list_add_tail(®->link, - &dev_priv->mm.fence_list); + i915_unreserve_fence(reg); + vgpu->fence.regs[i] = NULL; } mutex_unlock(&dev_priv->drm.struct_mutex); intel_runtime_pm_put(dev_priv); diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h index 38bd08f2539b..789f7502cd1f 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -3673,6 +3673,9 @@ i915_vm_to_ppgtt(struct i915_address_space *vm) /* i915_gem_fence_reg.c */ int __must_check i915_vma_get_fence(struct i915_vma *vma); int __must_check i915_vma_put_fence(struct i915_vma *vma); +struct drm_i915_fence_reg * +i915_reserve_fence(struct drm_i915_private *dev_priv); +void i915_unreserve_fence(struct drm_i915_fence_reg *fence); void i915_gem_revoke_fences(struct drm_i915_private *dev_priv); void i915_gem_restore_fences(struct drm_i915_private *dev_priv); diff --git a/drivers/gpu/drm/i915/i915_gem_fence_reg.c b/drivers/gpu/drm/i915/i915_gem_fence_reg.c index 5fe2cd8c8f28..2783d63bd1ad 100644 --- a/drivers/gpu/drm/i915/i915_gem_fence_reg.c +++ b/drivers/gpu/drm/i915/i915_gem_fence_reg.c @@ -359,6 +359,57 @@ i915_vma_get_fence(struct i915_vma *vma) return fence_update(fence, set); } +/** + * i915_reserve_fence - Reserve a fence for vGPU + * @dev_priv: i915 device private + * + * This function walks the fence regs looking for a free one and remove + * it from the fence_list. It is used to reserve fence for vGPU to use. + */ +struct drm_i915_fence_reg * +i915_reserve_fence(struct drm_i915_private *dev_priv) +{ + struct drm_i915_fence_reg *fence; + int count; + int ret; + + lockdep_assert_held(&dev_priv->drm.struct_mutex); + + /* Keep at least one fence available for the display engine. */ + count = 0; + list_for_each_entry(fence, &dev_priv->mm.fence_list, link) + count += !fence->pin_count; + if (count <= 1) + return ERR_PTR(-ENOSPC); + + fence = fence_find(dev_priv); + if (IS_ERR(fence)) + return fence; + + if (fence->vma) { + /* Force-remove fence from VMA */ + ret = fence_update(fence, NULL); + if (ret) + return ERR_PTR(ret); + } + + list_del(&fence->link); + return fence; +} + +/** + * i915_unreserve_fence - Reclaim a reserved fence + * @fence: the fence reg + * + * This function add a reserved fence register from vGPU to the fence_list. + */ +void i915_unreserve_fence(struct drm_i915_fence_reg *fence) +{ + lockdep_assert_held(&fence->i915->drm.struct_mutex); + + list_add(&fence->link, &fence->i915->mm.fence_list); +} + /** * i915_gem_revoke_fences - revoke fence state * @dev_priv: i915 device private