drm/xen: Major refactoring towards upstream

Signed-off-by: Oleksandr Andrushchenko <[email protected]>

drivers/gpu/drm/xen/Kconfig

@@ -5,6 +5,10 @@ config DRM_XEN
 	  Choose this option if you want to enable DRM support
 	  for Xen.
 
+choice
+	prompt "DRM driver sub-type selection"
+	depends on DRM_XEN
+
 config DRM_XEN_FRONTEND
 	tristate "Front-end paravirtualized driver for Xen guest OS"
 	depends on DRM_XEN
@@ -60,3 +64,6 @@ config DRM_XEN_ZCOPY_CMA
 	  This is only available for built-in driver, because
 	  there is a dependency on DMA ops which are only available
 	  for built-in code.
+
+endchoice
+

drivers/gpu/drm/xen/Makefile

@@ -2,15 +2,18 @@
 # Makefile for the drm device driver.  This driver provides support for the
 # Direct Rendering Infrastructure (DRI) in XFree86 4.1.0 and higher.
 
-drm_xen_front-objs := xen_drm_front.o xen_drm_drv.o xen_drm_kms.o xen_drm_crtc.o \
-		  xen_drm_timer.o xen_drm_shbuf.o
+drm_xen_front-objs := xen_drm_front.o xen_drm_front_drv.o xen_drm_front_kms.o \
+		      xen_drm_front_crtc.o xen_drm_front_timer.o xen_drm_front_shbuf.o \
+		      xen_drm_balloon.o xen_drm_front_evtchnl.o xen_drm_front_cfg.o
 
-ifneq ($(CONFIG_DRM_XEN_FRONTEND_CMA),y)
-	drm_xen_front-objs += xen_drm_gem.o
+ifeq ($(CONFIG_DRM_XEN_FRONTEND_CMA),y)
+       drm_xen_front-objs += xen_drm_front_gem_cma.o
+else
+       drm_xen_front-objs += xen_drm_front_gem.o
 endif
 
 obj-$(CONFIG_DRM_XEN_FRONTEND) += drm_xen_front.o
 
-drm_xen_zcopy-objs := xen_drm_zcopy_drv.o
+drm_xen_zcopy-objs := xen_drm_zcopy_drv.o xen_drm_balloon.o
 
 obj-$(CONFIG_DRM_XEN_ZCOPY) += drm_xen_zcopy.o

drivers/gpu/drm/xen/xen_drm_balloon.c

@@ -0,0 +1,154 @@
+/*
+ *  Xen para-virtual DRM device
+ *
+ *   This program is free software; you can redistribute it and/or modify
+ *   it under the terms of the GNU General Public License as published by
+ *   the Free Software Foundation; either version 2 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ *
+ * Copyright (C) 2016-2017 EPAM Systems Inc.
+ *
+ * Author: Oleksandr Andrushchenko <[email protected]>
+ */
+
+#include <drm/drmP.h>
+
+#if defined(CONFIG_DRM_XEN_ZCOPY_CMA)
+#include <asm/xen/hypercall.h>
+#include <xen/interface/memory.h>
+#include <xen/page.h>
+#else
+#include <xen/balloon.h>
+#endif
+
+#include "xen_drm_balloon.h"
+
+#if defined(CONFIG_DRM_XEN_ZCOPY_CMA)
+int xen_drm_ballooned_pages_alloc(struct device *dev,
+	struct xen_drm_balloon *obj, int num_pages, struct page **pages)
+{
+	xen_pfn_t *frame_list;
+	size_t size;
+	int i, ret;
+	dma_addr_t dev_addr, cpu_addr;
+	void *vaddr = NULL;
+	struct xen_memory_reservation reservation = {
+		.address_bits = 0,
+		.extent_order = 0,
+		.domid        = DOMID_SELF
+	};
+
+	size = num_pages * PAGE_SIZE;
+	DRM_DEBUG("Ballooning out %d pages, size %zu\n", num_pages, size);
+	frame_list = kcalloc(num_pages, sizeof(*frame_list), GFP_KERNEL);
+	if (!frame_list)
+		return -ENOMEM;
+
+	vaddr = dma_alloc_wc(dev, size, &dev_addr, GFP_KERNEL | __GFP_NOWARN);
+	if (!vaddr) {
+		DRM_ERROR("Failed to allocate DMA buffer with size %zu\n",
+			size);
+		ret = -ENOMEM;
+		goto fail;
+	}
+
+	cpu_addr = dev_addr;
+	for (i = 0; i < num_pages; i++) {
+		pages[i] = pfn_to_page(__phys_to_pfn(cpu_addr));
+		/* XENMEM_populate_physmap requires a PFN based on Xen
+		 * granularity.
+		 */
+		frame_list[i] = page_to_xen_pfn(pages[i]);
+		cpu_addr += PAGE_SIZE;
+	}
+	set_xen_guest_handle(reservation.extent_start, frame_list);
+	reservation.nr_extents = num_pages;
+	/* rc will hold number of pages processed */
+	ret = HYPERVISOR_memory_op(XENMEM_decrease_reservation, &reservation);
+	if (ret <= 0) {
+		DRM_ERROR("Failed to balloon out %d pages (%d), retrying\n",
+			num_pages, ret);
+		WARN_ON(ret != num_pages);
+		ret = -EFAULT;
+		goto fail;
+	}
+
+	obj->vaddr = vaddr;
+	obj->dev_bus_addr = dev_addr;
+	kfree(frame_list);
+	return 0;
+
+fail:
+	if (vaddr)
+		dma_free_wc(dev, size, vaddr, dev_addr);
+	kfree(frame_list);
+	return ret;
+}
+
+void xen_drm_ballooned_pages_free(struct device *dev,
+	struct xen_drm_balloon *obj, int num_pages, struct page **pages)
+{
+	xen_pfn_t *frame_list;
+	int i, ret;
+	size_t size;
+	struct xen_memory_reservation reservation = {
+		.address_bits = 0,
+		.extent_order = 0,
+		.domid        = DOMID_SELF
+	};
+
+	if (!pages)
+		return;
+
+	if (!obj->vaddr)
+		return;
+
+	frame_list = kcalloc(num_pages, sizeof(*frame_list), GFP_KERNEL);
+	if (!frame_list) {
+		DRM_ERROR("Failed to balloon in %d pages\n", num_pages);
+		return;
+	}
+
+	DRM_DEBUG("Ballooning in %d pages\n", num_pages);
+	size = num_pages * PAGE_SIZE;
+	for (i = 0; i < num_pages; i++) {
+		/*
+		 * XENMEM_populate_physmap requires a PFN based on Xen
+		 * granularity.
+		 */
+		frame_list[i] = page_to_xen_pfn(pages[i]);
+	}
+	set_xen_guest_handle(reservation.extent_start, frame_list);
+	reservation.nr_extents = num_pages;
+	/* rc will hold number of pages processed */
+	ret = HYPERVISOR_memory_op(XENMEM_populate_physmap, &reservation);
+	if (ret <= 0) {
+		DRM_ERROR("Failed to balloon in %d pages\n", num_pages);
+		WARN_ON(ret != num_pages);
+	}
+
+	if (obj->vaddr)
+		dma_free_wc(dev, size, obj->vaddr, obj->dev_bus_addr);
+
+	obj->vaddr = NULL;
+	obj->dev_bus_addr = 0;
+	kfree(frame_list);
+}
+#else
+int xen_drm_ballooned_pages_alloc(struct device *dev,
+	struct xen_drm_balloon *obj, int num_pages, struct page **pages)
+{
+	return alloc_xenballooned_pages(num_pages, pages);
+}
+
+void xen_drm_ballooned_pages_free(struct device *dev,
+	struct xen_drm_balloon *obj, int num_pages, struct page **pages)
+{
+	free_xenballooned_pages(num_pages, pages);
+}
+#endif /* defined(CONFIG_DRM_XEN_ZCOPY_CMA) */

drivers/gpu/drm/xen/xen_drm_balloon.h

@@ -0,0 +1,36 @@
+/*
+ *  Xen para-virtual DRM device
+ *
+ *   This program is free software; you can redistribute it and/or modify
+ *   it under the terms of the GNU General Public License as published by
+ *   the Free Software Foundation; either version 2 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ *
+ * Copyright (C) 2016-2017 EPAM Systems Inc.
+ *
+ * Author: Oleksandr Andrushchenko <[email protected]>
+ */
+
+#ifndef __XEN_DRM_BALLOON_H_
+#define __XEN_DRM_BALLOON_H_
+
+#define GRANT_INVALID_REF	0
+
+#include <linux/types.h>
+
+struct xen_drm_balloon {
+	void *vaddr;
+	dma_addr_t dev_bus_addr;
+};
+
+int xen_drm_ballooned_pages_alloc(struct device *dev,
+	struct xen_drm_balloon *obj, int num_pages, struct page **pages);
+void xen_drm_ballooned_pages_free(struct device *dev,
+	struct xen_drm_balloon *obj,int num_pages, struct page **pages);
+
+#endif /* __XEN_DRM_BALLOON_H_ */