drm/radeon: introduce kernel modesetting for radeon hardware

Add kernel modesetting support to radeon driver, use the ttm memory
manager to manage memory and DRM/GEM to provide userspace API.
In order to avoid backward compatibility issue and to allow clean
design and code the radeon kernel modesetting use different code path
than old radeon/drm driver.

When kernel modesetting is enabled the IOCTL of radeon/drm
driver are considered as invalid and an error message is printed
in the log and they return failure.

KMS enabled userspace will use new API to talk with the radeon/drm
driver. The new API provide functions to create/destroy/share/mmap
buffer object which are then managed by the kernel memory manager
(here TTM). In order to submit command to the GPU the userspace
provide a buffer holding the command stream, along this buffer
userspace have to provide a list of buffer object used by the
command stream. The kernel radeon driver will then place buffer
in GPU accessible memory and will update command stream to reflect
the position of the different buffers.

The kernel will also perform security check on command stream
provided by the user, we want to catch and forbid any illegal use
of the GPU such as DMA into random system memory or into memory
not owned by the process supplying the command stream. This part
of the code is still incomplete and this why we propose that patch
as a staging driver addition, future security might forbid current
experimental userspace to run.

This code support the following hardware : R1XX,R2XX,R3XX,R4XX,R5XX
(radeon up to X1950). Works is underway to provide support for R6XX,
R7XX and newer hardware (radeon from HD2XXX to HD4XXX).

Authors:
    Jerome Glisse <jglisse@redhat.com>
    Dave Airlie <airlied@redhat.com>
    Alex Deucher <alexdeucher@gmail.com>

Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Alex Deucher <alexdeucher@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

1 files changed, 249 insertions, 0 deletions

diff --git a/drivers/gpu/drm/radeon/radeon_cs.c b/drivers/gpu/drm/radeon/radeon_cs.c
new file mode 100644
index 0000000..b843f9b
--- /dev/null
+++ b/drivers/gpu/drm/radeon/radeon_cs.c
@@ -0,0 +1,249 @@
+/*
+ * Copyright 2008 Jerome Glisse.
+ * All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * PRECISION INSIGHT AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ *
+ * Authors:
+ *    Jerome Glisse <glisse@freedesktop.org>
+ */
+#include "drmP.h"
+#include "radeon_drm.h"
+#include "radeon_reg.h"
+#include "radeon.h"
+
+void r100_cs_dump_packet(struct radeon_cs_parser *p,
+			 struct radeon_cs_packet *pkt);
+
+int radeon_cs_parser_relocs(struct radeon_cs_parser *p)
+{
+	struct drm_device *ddev = p->rdev->ddev;
+	struct radeon_cs_chunk *chunk;
+	unsigned i, j;
+	bool duplicate;
+
+	if (p->chunk_relocs_idx == -1) {
+		return 0;
+	}
+	chunk = &p->chunks[p->chunk_relocs_idx];
+	/* FIXME: we assume that each relocs use 4 dwords */
+	p->nrelocs = chunk->length_dw / 4;
+	p->relocs_ptr = kcalloc(p->nrelocs, sizeof(void *), GFP_KERNEL);
+	if (p->relocs_ptr == NULL) {
+		return -ENOMEM;
+	}
+	p->relocs = kcalloc(p->nrelocs, sizeof(struct radeon_cs_reloc), GFP_KERNEL);
+	if (p->relocs == NULL) {
+		return -ENOMEM;
+	}
+	for (i = 0; i < p->nrelocs; i++) {
+		struct drm_radeon_cs_reloc *r;
+
+		duplicate = false;
+		r = (struct drm_radeon_cs_reloc *)&chunk->kdata[i*4];
+		for (j = 0; j < p->nrelocs; j++) {
+			if (r->handle == p->relocs[j].handle) {
+				p->relocs_ptr[i] = &p->relocs[j];
+				duplicate = true;
+				break;
+			}
+		}
+		if (!duplicate) {
+			p->relocs[i].gobj = drm_gem_object_lookup(ddev,
+								  p->filp,
+								  r->handle);
+			if (p->relocs[i].gobj == NULL) {
+				DRM_ERROR("gem object lookup failed 0x%x\n",
+					  r->handle);
+				return -EINVAL;
+			}
+			p->relocs_ptr[i] = &p->relocs[i];
+			p->relocs[i].robj = p->relocs[i].gobj->driver_private;
+			p->relocs[i].lobj.robj = p->relocs[i].robj;
+			p->relocs[i].lobj.rdomain = r->read_domains;
+			p->relocs[i].lobj.wdomain = r->write_domain;
+			p->relocs[i].handle = r->handle;
+			p->relocs[i].flags = r->flags;
+			INIT_LIST_HEAD(&p->relocs[i].lobj.list);
+			radeon_object_list_add_object(&p->relocs[i].lobj,
+						      &p->validated);
+		}
+	}
+	return radeon_object_list_validate(&p->validated, p->ib->fence);
+}
+
+int radeon_cs_parser_init(struct radeon_cs_parser *p, void *data)
+{
+	struct drm_radeon_cs *cs = data;
+	uint64_t *chunk_array_ptr;
+	unsigned size, i;
+
+	if (!cs->num_chunks) {
+		return 0;
+	}
+	/* get chunks */
+	INIT_LIST_HEAD(&p->validated);
+	p->idx = 0;
+	p->chunk_ib_idx = -1;
+	p->chunk_relocs_idx = -1;
+	p->chunks_array = kcalloc(cs->num_chunks, sizeof(uint64_t), GFP_KERNEL);
+	if (p->chunks_array == NULL) {
+		return -ENOMEM;
+	}
+	chunk_array_ptr = (uint64_t *)(unsigned long)(cs->chunks);
+	if (DRM_COPY_FROM_USER(p->chunks_array, chunk_array_ptr,
+			       sizeof(uint64_t)*cs->num_chunks)) {
+		return -EFAULT;
+	}
+	p->nchunks = cs->num_chunks;
+	p->chunks = kcalloc(p->nchunks, sizeof(struct radeon_cs_chunk), GFP_KERNEL);
+	if (p->chunks == NULL) {
+		return -ENOMEM;
+	}
+	for (i = 0; i < p->nchunks; i++) {
+		struct drm_radeon_cs_chunk __user **chunk_ptr = NULL;
+		struct drm_radeon_cs_chunk user_chunk;
+		uint32_t __user *cdata;
+
+		chunk_ptr = (void __user*)(unsigned long)p->chunks_array[i];
+		if (DRM_COPY_FROM_USER(&user_chunk, chunk_ptr,
+				       sizeof(struct drm_radeon_cs_chunk))) {
+			return -EFAULT;
+		}
+		p->chunks[i].chunk_id = user_chunk.chunk_id;
+		if (p->chunks[i].chunk_id == RADEON_CHUNK_ID_RELOCS) {
+			p->chunk_relocs_idx = i;
+		}
+		if (p->chunks[i].chunk_id == RADEON_CHUNK_ID_IB) {
+			p->chunk_ib_idx = i;
+		}
+		p->chunks[i].length_dw = user_chunk.length_dw;
+		cdata = (uint32_t *)(unsigned long)user_chunk.chunk_data;
+
+		p->chunks[i].kdata = NULL;
+		size = p->chunks[i].length_dw * sizeof(uint32_t);
+		p->chunks[i].kdata = kzalloc(size, GFP_KERNEL);
+		if (p->chunks[i].kdata == NULL) {
+			return -ENOMEM;
+		}
+		if (DRM_COPY_FROM_USER(p->chunks[i].kdata, cdata, size)) {
+			return -EFAULT;
+		}
+	}
+	if (p->chunks[p->chunk_ib_idx].length_dw > (16 * 1024)) {
+		DRM_ERROR("cs IB too big: %d\n",
+			  p->chunks[p->chunk_ib_idx].length_dw);
+		return -EINVAL;
+	}
+	return 0;
+}
+
+/**
+ * cs_parser_fini() - clean parser states
+ * @parser:	parser structure holding parsing context.
+ * @error:	error number
+ *
+ * If error is set than unvalidate buffer, otherwise just free memory
+ * used by parsing context.
+ **/
+static void radeon_cs_parser_fini(struct radeon_cs_parser *parser, int error)
+{
+	unsigned i;
+
+	if (error) {
+		radeon_object_list_unvalidate(&parser->validated);
+	} else {
+		radeon_object_list_clean(&parser->validated);
+	}
+	for (i = 0; i < parser->nrelocs; i++) {
+		if (parser->relocs[i].gobj) {
+			mutex_lock(&parser->rdev->ddev->struct_mutex);
+			drm_gem_object_unreference(parser->relocs[i].gobj);
+			mutex_unlock(&parser->rdev->ddev->struct_mutex);
+		}
+	}
+	kfree(parser->relocs);
+	kfree(parser->relocs_ptr);
+	for (i = 0; i < parser->nchunks; i++) {
+		kfree(parser->chunks[i].kdata);
+	}
+	kfree(parser->chunks);
+	kfree(parser->chunks_array);
+	radeon_ib_free(parser->rdev, &parser->ib);
+}
+
+int radeon_cs_ioctl(struct drm_device *dev, void *data, struct drm_file *filp)
+{
+	struct radeon_device *rdev = dev->dev_private;
+	struct radeon_cs_parser parser;
+	struct radeon_cs_chunk *ib_chunk;
+	int r;
+
+	mutex_lock(&rdev->cs_mutex);
+	if (rdev->gpu_lockup) {
+		mutex_unlock(&rdev->cs_mutex);
+		return -EINVAL;
+	}
+	/* initialize parser */
+	memset(&parser, 0, sizeof(struct radeon_cs_parser));
+	parser.filp = filp;
+	parser.rdev = rdev;
+	r = radeon_cs_parser_init(&parser, data);
+	if (r) {
+		DRM_ERROR("Failed to initialize parser !\n");
+		radeon_cs_parser_fini(&parser, r);
+		mutex_unlock(&rdev->cs_mutex);
+		return r;
+	}
+	r =  radeon_ib_get(rdev, &parser.ib);
+	if (r) {
+		DRM_ERROR("Failed to get ib !\n");
+		radeon_cs_parser_fini(&parser, r);
+		mutex_unlock(&rdev->cs_mutex);
+		return r;
+	}
+	r = radeon_cs_parser_relocs(&parser);
+	if (r) {
+		DRM_ERROR("Failed to parse relocation !\n");
+		radeon_cs_parser_fini(&parser, r);
+		mutex_unlock(&rdev->cs_mutex);
+		return r;
+	}
+	/* Copy the packet into the IB, the parser will read from the
+	 * input memory (cached) and write to the IB (which can be
+	 * uncached). */
+	ib_chunk = &parser.chunks[parser.chunk_ib_idx];
+	parser.ib->length_dw = ib_chunk->length_dw;
+	memcpy((void *)parser.ib->ptr, ib_chunk->kdata, ib_chunk->length_dw*4);
+	r = radeon_cs_parse(&parser);
+	if (r) {
+		DRM_ERROR("Invalid command stream !\n");
+		radeon_cs_parser_fini(&parser, r);
+		mutex_unlock(&rdev->cs_mutex);
+		return r;
+	}
+	r = radeon_ib_schedule(rdev, parser.ib);
+	if (r) {
+		DRM_ERROR("Faild to schedule IB !\n");
+	}
+	radeon_cs_parser_fini(&parser, r);
+	mutex_unlock(&rdev->cs_mutex);
+	return r;
+}