This patch implements the virtual GEM driver with PRIME sharing which allows vgem to import a gem object from other drivers for the purpose of mmap-ing them to userspace. The mmap is done using the mmap operation exported by other drivers.
v2: remove platform_device and do not attach to dma bufs
Reviewed-by: Stéphane Marchesin marcheu@chromium.org Signed-off-by: Adam Jackson ajax@redhat.com Signed-off-by: Ben Widawsky ben@bwidawsk.net Signed-off-by: Zach Reizner zachr@google.com --- drivers/gpu/drm/Kconfig | 9 + drivers/gpu/drm/Makefile | 1 + drivers/gpu/drm/vgem/Makefile | 4 + drivers/gpu/drm/vgem/vgem_dma_buf.c | 96 +++++++++ drivers/gpu/drm/vgem/vgem_drv.c | 390 ++++++++++++++++++++++++++++++++++++ drivers/gpu/drm/vgem/vgem_drv.h | 57 ++++++ 6 files changed, 557 insertions(+) create mode 100644 drivers/gpu/drm/vgem/Makefile create mode 100644 drivers/gpu/drm/vgem/vgem_dma_buf.c create mode 100644 drivers/gpu/drm/vgem/vgem_drv.c create mode 100644 drivers/gpu/drm/vgem/vgem_drv.h
diff --git a/drivers/gpu/drm/Kconfig b/drivers/gpu/drm/Kconfig index 308c104..b58f667 100644 --- a/drivers/gpu/drm/Kconfig +++ b/drivers/gpu/drm/Kconfig @@ -164,6 +164,15 @@ config DRM_SAVAGE Choose this option if you have a Savage3D/4/SuperSavage/Pro/Twister chipset. If M is selected the module will be called savage.
+config DRM_VGEM + tristate "Virtual GEM provider" + depends on DRM + help + Choose this option to get a virtual graphics memory manager, + as used by Mesa's software renderer for enhanced performance. + If M is selected the module will be called vgem. + + source "drivers/gpu/drm/exynos/Kconfig"
source "drivers/gpu/drm/rockchip/Kconfig" diff --git a/drivers/gpu/drm/Makefile b/drivers/gpu/drm/Makefile index 2c239b9..7d4944e 100644 --- a/drivers/gpu/drm/Makefile +++ b/drivers/gpu/drm/Makefile @@ -48,6 +48,7 @@ obj-$(CONFIG_DRM_SIS) += sis/ obj-$(CONFIG_DRM_SAVAGE)+= savage/ obj-$(CONFIG_DRM_VMWGFX)+= vmwgfx/ obj-$(CONFIG_DRM_VIA) +=via/ +obj-$(CONFIG_DRM_VGEM) += vgem/ obj-$(CONFIG_DRM_NOUVEAU) +=nouveau/ obj-$(CONFIG_DRM_EXYNOS) +=exynos/ obj-$(CONFIG_DRM_ROCKCHIP) +=rockchip/ diff --git a/drivers/gpu/drm/vgem/Makefile b/drivers/gpu/drm/vgem/Makefile new file mode 100644 index 0000000..1055cb7 --- /dev/null +++ b/drivers/gpu/drm/vgem/Makefile @@ -0,0 +1,4 @@ +ccflags-y := -Iinclude/drm +vgem-y := vgem_drv.o vgem_dma_buf.o + +obj-$(CONFIG_DRM_VGEM) += vgem.o diff --git a/drivers/gpu/drm/vgem/vgem_dma_buf.c b/drivers/gpu/drm/vgem/vgem_dma_buf.c new file mode 100644 index 0000000..3ea6bd2 --- /dev/null +++ b/drivers/gpu/drm/vgem/vgem_dma_buf.c @@ -0,0 +1,96 @@ +/* + * Copyright © 2012 Intel Corporation + * Copyright © 2014 The Chromium OS Authors + * + * 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 + * THE AUTHORS OR COPYRIGHT HOLDERS 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: + * Ben Widawsky ben@bwidawsk.net + * + */ + +#include <linux/dma-buf.h> +#include "vgem_drv.h" + +#define VGEM_FD_PERMS 0600 + +struct sg_table *vgem_gem_prime_get_sg_table(struct drm_gem_object *gobj) +{ + struct drm_vgem_gem_object *obj = to_vgem_bo(gobj); + BUG_ON(obj->pages == NULL); + + return drm_prime_pages_to_sg(obj->pages, obj->base.size / PAGE_SIZE); +} + +int vgem_gem_prime_pin(struct drm_gem_object *gobj) +{ + struct drm_vgem_gem_object *obj = to_vgem_bo(gobj); + return vgem_gem_get_pages(obj); +} + +void vgem_gem_prime_unpin(struct drm_gem_object *gobj) +{ + struct drm_vgem_gem_object *obj = to_vgem_bo(gobj); + vgem_gem_put_pages(obj); +} + +void *vgem_gem_prime_vmap(struct drm_gem_object *gobj) +{ + struct drm_vgem_gem_object *obj = to_vgem_bo(gobj); + BUG_ON(obj->pages == NULL); + + return vmap(obj->pages, obj->base.size / PAGE_SIZE, 0, PAGE_KERNEL); +} + +void vgem_gem_prime_vunmap(struct drm_gem_object *obj, void *vaddr) +{ + vunmap(vaddr); +} + +struct drm_gem_object *vgem_gem_prime_import(struct drm_device *dev, + struct dma_buf *dma_buf) +{ + struct drm_vgem_gem_object *obj = NULL; + int ret; + + obj = kzalloc(sizeof(*obj), GFP_KERNEL); + if (obj == NULL) { + ret = -ENOMEM; + goto fail; + } + + ret = drm_gem_object_init(dev, &obj->base, dma_buf->size); + if (ret) { + ret = -ENOMEM; + goto fail_free; + } + + get_dma_buf(dma_buf); + + obj->base.dma_buf = dma_buf; + obj->use_dma_buf = true; + + return &obj->base; + +fail_free: + kfree(obj); +fail: + return ERR_PTR(ret); +} diff --git a/drivers/gpu/drm/vgem/vgem_drv.c b/drivers/gpu/drm/vgem/vgem_drv.c new file mode 100644 index 0000000..e20f4a4 --- /dev/null +++ b/drivers/gpu/drm/vgem/vgem_drv.c @@ -0,0 +1,390 @@ +/* + * Copyright 2011 Red Hat, Inc. + * Copyright © 2014 The Chromium OS Authors + * + * 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 + * on the rights to use, copy, modify, merge, publish, distribute, sub + * license, and/or sell copies of the Software, and to permit persons to whom + * them 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 MERCHANTIBILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS 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: + * Adam Jackson ajax@redhat.com + * Ben Widawsky ben@bwidawsk.net + */ + +/** + * This is vgem, a (non-hardware-backed) GEM service. This is used by Mesa's + * software renderer and the X server for efficient buffer sharing. + */ + +#include <linux/module.h> +#include <linux/ramfs.h> +#include <linux/shmem_fs.h> +#include <linux/dma-buf.h> +#include "vgem_drv.h" + +#define DRIVER_NAME "vgem" +#define DRIVER_DESC "Virtual GEM provider" +#define DRIVER_DATE "20120112" +#define DRIVER_MAJOR 1 +#define DRIVER_MINOR 0 + +void vgem_gem_put_pages(struct drm_vgem_gem_object *obj) +{ + int num_pages = obj->base.size / PAGE_SIZE; + int i; + + for (i = 0; i < num_pages; i++) { + if (obj->pages[i] == NULL) + break; + page_cache_release(obj->pages[i]); + } + + drm_free_large(obj->pages); + obj->pages = NULL; +} + +static void vgem_gem_free_object(struct drm_gem_object *obj) +{ + struct drm_vgem_gem_object *vgem_obj = to_vgem_bo(obj); + + drm_gem_free_mmap_offset(obj); + + if (vgem_obj->use_dma_buf && obj->dma_buf) { + dma_buf_put(obj->dma_buf); + obj->dma_buf = NULL; + } + + drm_gem_object_release(obj); + + if (vgem_obj->pages) + vgem_gem_put_pages(vgem_obj); + + vgem_obj->pages = NULL; + + kfree(vgem_obj); +} + +int vgem_gem_get_pages(struct drm_vgem_gem_object *obj) +{ + struct address_space *mapping; + gfp_t gfpmask = GFP_KERNEL; + int num_pages, i, ret = 0; + + if (obj->pages || obj->use_dma_buf) + return 0; + + num_pages = obj->base.size / PAGE_SIZE; + obj->pages = drm_malloc_ab(num_pages, sizeof(struct page *)); + if (obj->pages == NULL) + return -ENOMEM; + + mapping = obj->base.filp->f_path.dentry->d_inode->i_mapping; + gfpmask |= mapping_gfp_mask(mapping); + + for (i = 0; i < num_pages; i++) { + struct page *page; + obj->pages[i] = NULL; + page = shmem_read_mapping_page_gfp(mapping, i, gfpmask); + if (IS_ERR(page)) { + ret = PTR_ERR(page); + goto err_out; + } + obj->pages[i] = page; + } + + return ret; + +err_out: + vgem_gem_put_pages(obj); + return ret; +} + +static int vgem_gem_fault(struct vm_area_struct *vma, struct vm_fault *vmf) +{ + struct drm_vgem_gem_object *obj = vma->vm_private_data; + struct drm_device *dev = obj->base.dev; + loff_t num_pages; + pgoff_t page_offset; + int ret; + + /* We don't use vmf->pgoff since that has the fake offset */ + page_offset = ((unsigned long)vmf->virtual_address - vma->vm_start) >> + PAGE_SHIFT; + + num_pages = DIV_ROUND_UP(obj->base.size, PAGE_SIZE); + + if (page_offset > num_pages) + return VM_FAULT_SIGBUS; + + mutex_lock(&dev->struct_mutex); + + ret = vm_insert_page(vma, (unsigned long)vmf->virtual_address, + obj->pages[page_offset]); + + mutex_unlock(&dev->struct_mutex); + switch (ret) { + case 0: + return VM_FAULT_NOPAGE; + case -ENOMEM: + return VM_FAULT_OOM; + case -EBUSY: + return VM_FAULT_RETRY; + case -EFAULT: + case -EINVAL: + return VM_FAULT_SIGBUS; + default: + WARN_ON(1); + return VM_FAULT_SIGBUS; + } +} + +static struct vm_operations_struct vgem_gem_vm_ops = { + .fault = vgem_gem_fault, + .open = drm_gem_vm_open, + .close = drm_gem_vm_close, +}; + +/* ioctls */ + +static struct drm_gem_object *vgem_gem_create(struct drm_device *dev, + struct drm_file *file, + unsigned int *handle, + unsigned long size) +{ + struct drm_vgem_gem_object *obj; + struct drm_gem_object *gem_object; + int err; + + size = roundup(size, PAGE_SIZE); + + obj = kzalloc(sizeof(*obj), GFP_KERNEL); + if (!obj) + return ERR_PTR(-ENOMEM); + + gem_object = &obj->base; + + err = drm_gem_object_init(dev, gem_object, size); + if (err) + goto out; + + err = drm_gem_handle_create(file, gem_object, handle); + if (err) + goto handle_out; + + drm_gem_object_unreference_unlocked(gem_object); + + return gem_object; + +handle_out: + drm_gem_object_release(gem_object); +out: + kfree(obj); + return ERR_PTR(err); +} + +static int vgem_gem_dumb_create(struct drm_file *file, struct drm_device *dev, + struct drm_mode_create_dumb *args) +{ + struct drm_gem_object *gem_object; + uint64_t size; + + size = args->height * args->width * DIV_ROUND_UP(args->bpp, 8); + if (size == 0) + return -EINVAL; + + gem_object = vgem_gem_create(dev, file, &args->handle, size); + + if (IS_ERR(gem_object)) { + DRM_DEBUG_DRIVER("object creation failed\n"); + return PTR_ERR(gem_object); + } + + args->size = gem_object->size; + args->pitch = args->width; + + DRM_DEBUG_DRIVER("Created object of size %lld\n", size); + + return 0; +} + +int vgem_gem_dumb_map(struct drm_file *file, struct drm_device *dev, + uint32_t handle, uint64_t *offset) +{ + int ret = 0; + struct drm_gem_object *obj; + + mutex_lock(&dev->struct_mutex); + obj = drm_gem_object_lookup(dev, file, handle); + if (!obj) { + ret = -ENOENT; + goto unlock; + } + + if (!drm_vma_node_has_offset(&obj->vma_node)) { + ret = drm_gem_create_mmap_offset(obj); + if (ret) + goto unref; + } + + BUG_ON(!obj->filp); + + obj->filp->private_data = obj; + + ret = vgem_gem_get_pages(to_vgem_bo(obj)); + if (ret) + goto fail_get_pages; + + *offset = drm_vma_node_offset_addr(&obj->vma_node); + + goto unref; + +fail_get_pages: + drm_gem_free_mmap_offset(obj); +unref: + drm_gem_object_unreference(obj); +unlock: + mutex_unlock(&dev->struct_mutex); + return ret; +} + +int vgem_drm_gem_mmap(struct file *filp, struct vm_area_struct *vma) +{ + struct drm_file *priv = filp->private_data; + struct drm_device *dev = priv->minor->dev; + struct drm_vma_offset_node *node; + struct drm_gem_object *obj; + struct drm_vgem_gem_object *vgem_obj; + int ret = 0; + + mutex_lock(&dev->struct_mutex); + + node = drm_vma_offset_exact_lookup(dev->vma_offset_manager, + vma->vm_pgoff, + vma_pages(vma)); + if (!node) { + ret = -EINVAL; + goto out_unlock; + } else if (!drm_vma_node_is_allowed(node, filp)) { + ret = -EACCES; + goto out_unlock; + } + + obj = container_of(node, struct drm_gem_object, vma_node); + + vgem_obj = to_vgem_bo(obj); + + if (obj->dma_buf && vgem_obj->use_dma_buf) { + ret = dma_buf_mmap(obj->dma_buf, vma, 0); + goto out_unlock; + } + + if (!obj->dev->driver->gem_vm_ops) { + ret = -EINVAL; + goto out_unlock; + } + + vma->vm_flags |= VM_IO | VM_MIXEDMAP | VM_DONTEXPAND | VM_DONTDUMP; + vma->vm_ops = obj->dev->driver->gem_vm_ops; + vma->vm_private_data = vgem_obj; + vma->vm_page_prot = + pgprot_writecombine(vm_get_page_prot(vma->vm_flags)); + + mutex_unlock(&dev->struct_mutex); + drm_gem_vm_open(vma); + return ret; + +out_unlock: + mutex_unlock(&dev->struct_mutex); + + return ret; +} + + +static struct drm_ioctl_desc vgem_ioctls[] = { +}; + +static const struct file_operations vgem_driver_fops = { + .owner = THIS_MODULE, + .open = drm_open, + .mmap = vgem_drm_gem_mmap, + .poll = drm_poll, + .read = drm_read, + .unlocked_ioctl = drm_ioctl, + .release = drm_release, +}; + +static struct drm_driver vgem_driver = { + .driver_features = DRIVER_GEM | DRIVER_PRIME, + .gem_free_object = vgem_gem_free_object, + .gem_vm_ops = &vgem_gem_vm_ops, + .ioctls = vgem_ioctls, + .fops = &vgem_driver_fops, + .dumb_create = vgem_gem_dumb_create, + .dumb_map_offset = vgem_gem_dumb_map, + .prime_handle_to_fd = drm_gem_prime_handle_to_fd, + .prime_fd_to_handle = drm_gem_prime_fd_to_handle, + .gem_prime_export = drm_gem_prime_export, + .gem_prime_import = vgem_gem_prime_import, + .gem_prime_pin = vgem_gem_prime_pin, + .gem_prime_unpin = vgem_gem_prime_unpin, + .gem_prime_get_sg_table = vgem_gem_prime_get_sg_table, + .gem_prime_vmap = vgem_gem_prime_vmap, + .gem_prime_vunmap = vgem_gem_prime_vunmap, + .name = DRIVER_NAME, + .desc = DRIVER_DESC, + .date = DRIVER_DATE, + .major = DRIVER_MAJOR, + .minor = DRIVER_MINOR, +}; + +struct drm_device *vgem_device; + +static int __init vgem_init(void) +{ + int ret; + + vgem_device = drm_dev_alloc(&vgem_driver, NULL); + if (!vgem_device) { + ret = -ENOMEM; + goto out; + } + + ret = drm_dev_register(vgem_device, 0); + + if (ret) + goto out_unref; + + return 0; + +out_unref: + drm_dev_unref(vgem_device); +out: + return ret; +} + +static void __exit vgem_exit(void) +{ + drm_dev_unregister(vgem_device); + drm_dev_unref(vgem_device); +} + +module_init(vgem_init); +module_exit(vgem_exit); + +MODULE_AUTHOR("Red Hat, Inc."); +MODULE_DESCRIPTION(DRIVER_DESC); +MODULE_LICENSE("GPL and additional rights"); diff --git a/drivers/gpu/drm/vgem/vgem_drv.h b/drivers/gpu/drm/vgem/vgem_drv.h new file mode 100644 index 0000000..57ab4d8 --- /dev/null +++ b/drivers/gpu/drm/vgem/vgem_drv.h @@ -0,0 +1,57 @@ +/* + * Copyright © 2012 Intel Corporation + * Copyright © 2014 The Chromium OS Authors + * + * 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 + * THE AUTHORS OR COPYRIGHT HOLDERS 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: + * Ben Widawsky ben@bwidawsk.net + * + */ + +#ifndef _VGEM_DRV_H_ +#define _VGEM_DRV_H_ + +#include <drm/drmP.h> +#include <drm/drm_gem.h> + +#define to_vgem_bo(x) container_of(x, struct drm_vgem_gem_object, base) +struct drm_vgem_gem_object { + struct drm_gem_object base; + struct page **pages; + bool use_dma_buf; +}; + +/* vgem_drv.c */ +extern void vgem_gem_put_pages(struct drm_vgem_gem_object *obj); +extern int vgem_gem_get_pages(struct drm_vgem_gem_object *obj); + +/* vgem_dma_buf.c */ +extern struct sg_table *vgem_gem_prime_get_sg_table( + struct drm_gem_object *gobj); +extern int vgem_gem_prime_pin(struct drm_gem_object *gobj); +extern void vgem_gem_prime_unpin(struct drm_gem_object *gobj); +extern void *vgem_gem_prime_vmap(struct drm_gem_object *gobj); +extern void vgem_gem_prime_vunmap(struct drm_gem_object *obj, void *vaddr); +extern struct drm_gem_object *vgem_gem_prime_import(struct drm_device *dev, + struct dma_buf *dma_buf); + + +#endif