diff options
Diffstat (limited to 'drivers/gpu/drm/i915/i915_vgpu.c')
| -rw-r--r-- | drivers/gpu/drm/i915/i915_vgpu.c | 178 |
1 files changed, 178 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/i915_vgpu.c b/drivers/gpu/drm/i915/i915_vgpu.c index 995a6003ed78..5eee75bff170 100644 --- a/drivers/gpu/drm/i915/i915_vgpu.c +++ b/drivers/gpu/drm/i915/i915_vgpu.c @@ -84,3 +84,181 @@ void i915_check_vgpu(struct drm_device *dev) dev_priv->vgpu.active = true; DRM_INFO("Virtual GPU for Intel GVT-g detected.\n"); } + +struct _balloon_info_ { + /* + * There are up to 2 regions per mappable/unmappable graphic + * memory that might be ballooned. Here, index 0/1 is for mappable + * graphic memory, 2/3 for unmappable graphic memory. + */ + struct drm_mm_node space[4]; +}; + +static struct _balloon_info_ bl_info; + +/** + * intel_vgt_deballoon - deballoon reserved graphics address trunks + * + * This function is called to deallocate the ballooned-out graphic memory, when + * driver is unloaded or when ballooning fails. + */ +void intel_vgt_deballoon(void) +{ + int i; + + DRM_DEBUG("VGT deballoon.\n"); + + for (i = 0; i < 4; i++) { + if (bl_info.space[i].allocated) + drm_mm_remove_node(&bl_info.space[i]); + } + + memset(&bl_info, 0, sizeof(bl_info)); +} + +static int vgt_balloon_space(struct drm_mm *mm, + struct drm_mm_node *node, + unsigned long start, unsigned long end) +{ + unsigned long size = end - start; + + if (start == end) + return -EINVAL; + + DRM_INFO("balloon space: range [ 0x%lx - 0x%lx ] %lu KiB.\n", + start, end, size / 1024); + + node->start = start; + node->size = size; + + return drm_mm_reserve_node(mm, node); +} + +/** + * intel_vgt_balloon - balloon out reserved graphics address trunks + * @dev: drm device + * + * This function is called at the initialization stage, to balloon out the + * graphic address space allocated to other vGPUs, by marking these spaces as + * reserved. The ballooning related knowledge(starting address and size of + * the mappable/unmappable graphic memory) is described in the vgt_if structure + * in a reserved mmio range. + * + * To give an example, the drawing below depicts one typical scenario after + * ballooning. Here the vGPU1 has 2 pieces of graphic address spaces ballooned + * out each for the mappable and the non-mappable part. From the vGPU1 point of + * view, the total size is the same as the physical one, with the start address + * of its graphic space being zero. Yet there are some portions ballooned out( + * the shadow part, which are marked as reserved by drm allocator). From the + * host point of view, the graphic address space is partitioned by multiple + * vGPUs in different VMs. + * + * vGPU1 view Host view + * 0 ------> +-----------+ +-----------+ + * ^ |///////////| | vGPU3 | + * | |///////////| +-----------+ + * | |///////////| | vGPU2 | + * | +-----------+ +-----------+ + * mappable GM | available | ==> | vGPU1 | + * | +-----------+ +-----------+ + * | |///////////| | | + * v |///////////| | Host | + * +=======+===========+ +===========+ + * ^ |///////////| | vGPU3 | + * | |///////////| +-----------+ + * | |///////////| | vGPU2 | + * | +-----------+ +-----------+ + * unmappable GM | available | ==> | vGPU1 | + * | +-----------+ +-----------+ + * | |///////////| | | + * | |///////////| | Host | + * v |///////////| | | + * total GM size ------> +-----------+ +-----------+ + * + * Returns: + * zero on success, non-zero if configuration invalid or ballooning failed + */ +int intel_vgt_balloon(struct drm_device *dev) +{ + struct drm_i915_private *dev_priv = to_i915(dev); + struct i915_address_space *ggtt_vm = &dev_priv->gtt.base; + unsigned long ggtt_vm_end = ggtt_vm->start + ggtt_vm->total; + + unsigned long mappable_base, mappable_size, mappable_end; + unsigned long unmappable_base, unmappable_size, unmappable_end; + int ret; + + mappable_base = I915_READ(vgtif_reg(avail_rs.mappable_gmadr.base)); + mappable_size = I915_READ(vgtif_reg(avail_rs.mappable_gmadr.size)); + unmappable_base = I915_READ(vgtif_reg(avail_rs.nonmappable_gmadr.base)); + unmappable_size = I915_READ(vgtif_reg(avail_rs.nonmappable_gmadr.size)); + + mappable_end = mappable_base + mappable_size; + unmappable_end = unmappable_base + unmappable_size; + + DRM_INFO("VGT ballooning configuration:\n"); + DRM_INFO("Mappable graphic memory: base 0x%lx size %ldKiB\n", + mappable_base, mappable_size / 1024); + DRM_INFO("Unmappable graphic memory: base 0x%lx size %ldKiB\n", + unmappable_base, unmappable_size / 1024); + + if (mappable_base < ggtt_vm->start || + mappable_end > dev_priv->gtt.mappable_end || + unmappable_base < dev_priv->gtt.mappable_end || + unmappable_end > ggtt_vm_end) { + DRM_ERROR("Invalid ballooning configuration!\n"); + return -EINVAL; + } + + /* Unmappable graphic memory ballooning */ + if (unmappable_base > dev_priv->gtt.mappable_end) { + ret = vgt_balloon_space(&ggtt_vm->mm, + &bl_info.space[2], + dev_priv->gtt.mappable_end, + unmappable_base); + + if (ret) + goto err; + } + + /* + * No need to partition out the last physical page, + * because it is reserved to the guard page. + */ + if (unmappable_end < ggtt_vm_end - PAGE_SIZE) { + ret = vgt_balloon_space(&ggtt_vm->mm, + &bl_info.space[3], + unmappable_end, + ggtt_vm_end - PAGE_SIZE); + if (ret) + goto err; + } + + /* Mappable graphic memory ballooning */ + if (mappable_base > ggtt_vm->start) { + ret = vgt_balloon_space(&ggtt_vm->mm, + &bl_info.space[0], + ggtt_vm->start, mappable_base); + + if (ret) + goto err; + } + + if (mappable_end < dev_priv->gtt.mappable_end) { + ret = vgt_balloon_space(&ggtt_vm->mm, + &bl_info.space[1], + mappable_end, + dev_priv->gtt.mappable_end); + + if (ret) + goto err; + } + + DRM_INFO("VGT balloon successfully\n"); + return 0; + +err: + DRM_ERROR("VGT balloon fail\n"); + intel_vgt_deballoon(); + return ret; +} |