Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754061AbdFMW31 (ORCPT ); Tue, 13 Jun 2017 18:29:27 -0400 Received: from mx1.redhat.com ([209.132.183.28]:46852 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753996AbdFMW3X (ORCPT ); Tue, 13 Jun 2017 18:29:23 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 46D437F342 Authentication-Results: ext-mx02.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx02.extmail.prod.ext.phx2.redhat.com; spf=pass smtp.mailfrom=alex.williamson@redhat.com DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.redhat.com 46D437F342 Date: Tue, 13 Jun 2017 16:29:13 -0600 From: Alex Williamson To: Xiaoguang Chen Cc: kraxel@redhat.com, chris@chris-wilson.co.uk, intel-gfx@lists.freedesktop.org, linux-kernel@vger.kernel.org, zhenyuw@linux.intel.com, zhiyuan.lv@intel.com, intel-gvt-dev@lists.freedesktop.org, zhi.a.wang@intel.com, kevin.tian@intel.com Subject: Re: [PATCH v8 6/6] drm/i915/gvt: Adding user interface for dma-buf Message-ID: <20170613162913.24404921@w520.home> In-Reply-To: <1496991042-2265-7-git-send-email-xiaoguang.chen@intel.com> References: <1496991042-2265-1-git-send-email-xiaoguang.chen@intel.com> <1496991042-2265-7-git-send-email-xiaoguang.chen@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.26]); Tue, 13 Jun 2017 22:29:17 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 13165 Lines: 418 On Fri, 9 Jun 2017 14:50:42 +0800 Xiaoguang Chen wrote: > User space should create the management fd for the dma-buf operation first. > Then user can query the plane information and create dma-buf if necessary > using the management fd. > > Signed-off-by: Xiaoguang Chen > Tested-by: Kechen Lu > --- > drivers/gpu/drm/i915/gvt/dmabuf.c | 37 ++++++++- > drivers/gpu/drm/i915/gvt/dmabuf.h | 5 ++ > drivers/gpu/drm/i915/gvt/gvt.c | 3 + > drivers/gpu/drm/i915/gvt/gvt.h | 5 ++ > drivers/gpu/drm/i915/gvt/hypercall.h | 3 + > drivers/gpu/drm/i915/gvt/kvmgt.c | 145 +++++++++++++++++++++++++++++++++++ > drivers/gpu/drm/i915/gvt/mpt.h | 30 ++++++++ > drivers/gpu/drm/i915/gvt/vgpu.c | 2 + > 8 files changed, 229 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/i915/gvt/dmabuf.c b/drivers/gpu/drm/i915/gvt/dmabuf.c > index c38ed8e9fc..1811abd 100644 > --- a/drivers/gpu/drm/i915/gvt/dmabuf.c > +++ b/drivers/gpu/drm/i915/gvt/dmabuf.c > @@ -81,6 +81,28 @@ static void intel_vgpu_gem_put_pages(struct drm_i915_gem_object *obj, > > static void intel_vgpu_gem_release(struct drm_i915_gem_object *obj) > { > + struct intel_vgpu_dmabuf_obj *dmabuf_obj; > + struct intel_vgpu_fb_info *fb_info; > + struct intel_vgpu *vgpu = NULL; unnecessary initialization > + struct list_head *pos; > + > + fb_info = (struct intel_vgpu_fb_info *)obj->gvt_info; > + if (WARN_ON(!fb_info && !fb_info->vgpu)) { || > + gvt_vgpu_err("gvt info is invalid\n"); > + goto out; > + } > + > + vgpu = fb_info->vgpu; > + list_for_each(pos, &vgpu->dmabuf_obj_list_head) { > + dmabuf_obj = container_of(pos, struct intel_vgpu_dmabuf_obj, > + list); > + if ((dmabuf_obj != NULL) && (dmabuf_obj->obj == obj)) { > + kfree(dmabuf_obj); > + break; Did we intend to remove it from the list? > + } > + } > + intel_gvt_hypervisor_put_vfio_device(vgpu); > +out: > kfree(obj->gvt_info); > } > > @@ -215,6 +237,7 @@ int intel_vgpu_create_dmabuf(struct intel_vgpu *vgpu, void *args) > struct vfio_vgpu_create_dmabuf *gvt_dmabuf = args; > struct intel_vgpu_fb_info *fb_info; > int ret; > + struct intel_vgpu_dmabuf_obj *dmabuf_obj; > > ret = intel_vgpu_get_plane_info(dev, vgpu, &gvt_dmabuf->plane_info, > gvt_dmabuf->plane_id); > @@ -237,6 +260,16 @@ int intel_vgpu_create_dmabuf(struct intel_vgpu *vgpu, void *args) > fb_info->vgpu = vgpu; > obj->gvt_info = fb_info; > > + dmabuf_obj = kmalloc(sizeof(*dmabuf_obj), GFP_KERNEL); > + if (!dmabuf_obj) { > + gvt_vgpu_err("alloc dmabuf_obj failed\n"); > + ret = -ENOMEM; > + goto out_free_info; > + } > + dmabuf_obj->obj = obj; > + INIT_LIST_HEAD(&dmabuf_obj->list); > + list_add_tail(&dmabuf_obj->list, &vgpu->dmabuf_obj_list_head); Does this list need protection? > + > dmabuf = i915_gem_prime_export(dev, &obj->base, DRM_CLOEXEC | DRM_RDWR); > > if (IS_ERR(dmabuf)) { > @@ -250,11 +283,13 @@ int intel_vgpu_create_dmabuf(struct intel_vgpu *vgpu, void *args) > gvt_vgpu_err("create dma-buf fd failed ret:%d\n", ret); > goto out_free; > } > - > + intel_gvt_hypervisor_get_vfio_device(vgpu); > gvt_dmabuf->fd = ret; > > return 0; > out_free: > + kfree(dmabuf_obj); > +out_free_info: > kfree(fb_info); > out: > i915_gem_object_put(obj); > diff --git a/drivers/gpu/drm/i915/gvt/dmabuf.h b/drivers/gpu/drm/i915/gvt/dmabuf.h > index 8be9979..cafa781 100644 > --- a/drivers/gpu/drm/i915/gvt/dmabuf.h > +++ b/drivers/gpu/drm/i915/gvt/dmabuf.h > @@ -31,6 +31,11 @@ struct intel_vgpu_fb_info { > uint32_t fb_size; > }; > > +struct intel_vgpu_dmabuf_obj { > + struct drm_i915_gem_object *obj; > + struct list_head list; > +}; > + > int intel_vgpu_query_plane(struct intel_vgpu *vgpu, void *args); > int intel_vgpu_create_dmabuf(struct intel_vgpu *vgpu, void *args); > > diff --git a/drivers/gpu/drm/i915/gvt/gvt.c b/drivers/gpu/drm/i915/gvt/gvt.c > index 2032917..d589830 100644 > --- a/drivers/gpu/drm/i915/gvt/gvt.c > +++ b/drivers/gpu/drm/i915/gvt/gvt.c > @@ -54,6 +54,9 @@ static const struct intel_gvt_ops intel_gvt_ops = { > .vgpu_reset = intel_gvt_reset_vgpu, > .vgpu_activate = intel_gvt_activate_vgpu, > .vgpu_deactivate = intel_gvt_deactivate_vgpu, > + .vgpu_query_plane = intel_vgpu_query_plane, > + .vgpu_create_dmabuf = intel_vgpu_create_dmabuf, > + > }; > > /** > diff --git a/drivers/gpu/drm/i915/gvt/gvt.h b/drivers/gpu/drm/i915/gvt/gvt.h > index 763a8c5..8f08c42 100644 > --- a/drivers/gpu/drm/i915/gvt/gvt.h > +++ b/drivers/gpu/drm/i915/gvt/gvt.h > @@ -185,8 +185,11 @@ struct intel_vgpu { > struct kvm *kvm; > struct work_struct release_work; > atomic_t released; > + struct vfio_device *vfio_device; > } vdev; > #endif > + atomic_t mgr_fd_opened; > + struct list_head dmabuf_obj_list_head; > }; > > struct intel_gvt_gm { > @@ -467,6 +470,8 @@ struct intel_gvt_ops { > void (*vgpu_reset)(struct intel_vgpu *); > void (*vgpu_activate)(struct intel_vgpu *); > void (*vgpu_deactivate)(struct intel_vgpu *); > + int (*vgpu_query_plane)(struct intel_vgpu *vgpu, void *); > + int (*vgpu_create_dmabuf)(struct intel_vgpu *vgpu, void *); > }; > > > diff --git a/drivers/gpu/drm/i915/gvt/hypercall.h b/drivers/gpu/drm/i915/gvt/hypercall.h > index 32c345c..8f29c23 100644 > --- a/drivers/gpu/drm/i915/gvt/hypercall.h > +++ b/drivers/gpu/drm/i915/gvt/hypercall.h > @@ -56,6 +56,9 @@ struct intel_gvt_mpt { > int (*set_trap_area)(unsigned long handle, u64 start, u64 end, > bool map); > int (*set_opregion)(void *vgpu); > + int (*get_vfio_device)(unsigned long handle); > + void (*put_vfio_device)(unsigned long handle); > + > }; > > extern struct intel_gvt_mpt xengt_mpt; > diff --git a/drivers/gpu/drm/i915/gvt/kvmgt.c b/drivers/gpu/drm/i915/gvt/kvmgt.c > index 6b4652a..e1d3492 100644 > --- a/drivers/gpu/drm/i915/gvt/kvmgt.c > +++ b/drivers/gpu/drm/i915/gvt/kvmgt.c > @@ -41,6 +41,7 @@ > #include > #include > #include > +#include > > #include "i915_drv.h" > #include "gvt.h" > @@ -523,6 +524,117 @@ static int kvmgt_set_opregion(void *p_vgpu) > return ret; > } > > +static int kvmgt_get_vfio_device(unsigned long handle) > +{ > + struct kvmgt_guest_info *info; > + struct intel_vgpu *vgpu; > + struct vfio_device *device; > + > + if (!handle_valid(handle)) > + return -ESRCH; > + > + info = (struct kvmgt_guest_info *)handle; > + vgpu = info->vgpu; > + > + device = vfio_device_get_from_dev(mdev_dev(vgpu->vdev.mdev)); > + if (device == NULL) > + return -ENODEV; > + vgpu->vdev.vfio_device = device; > + > + return 0; > +} > + > +static void kvmgt_put_vfio_device(unsigned long handle) > +{ > + struct kvmgt_guest_info *info; > + struct intel_vgpu *vgpu; > + > + if (!handle_valid(handle)) > + return; > + > + info = (struct kvmgt_guest_info *)handle; > + vgpu = info->vgpu; > + > + vfio_device_put(vgpu->vdev.vfio_device); > +} > + > +static int intel_vgpu_dmabuf_mgr_fd_mmap(struct file *file, > + struct vm_area_struct *vma) > +{ > + return -EPERM; > +} > + > +static int intel_vgpu_dmabuf_mgr_fd_release(struct inode *inode, > + struct file *filp) > +{ > + struct intel_vgpu *vgpu = filp->private_data; > + struct intel_vgpu_dmabuf_obj *obj; > + struct list_head *pos; > + > + if (WARN_ON(!vgpu->vdev.vfio_device)) Doesn't seem possible, however any kvmgt_put_vfio_device() call will set this regardless of whether that calling path retained the reference or failed and released it, so the way vfio_device is cached here is rather sketchy in general. > + return -ENODEV; > + > + list_for_each(pos, &vgpu->dmabuf_obj_list_head) { > + obj = container_of(pos, struct intel_vgpu_dmabuf_obj, list); > + if (WARN_ON(!obj)) > + return -ENODEV; > + i915_gem_object_put(obj->obj); > + } > + kvmgt_put_vfio_device(vgpu->handle); > + atomic_set(&vgpu->mgr_fd_opened, 0); > + > + return 0; > +} > + > +static long intel_vgpu_dmabuf_mgr_fd_ioctl(struct file *filp, > + unsigned int ioctl, unsigned long arg) > +{ > + struct intel_vgpu *vgpu = filp->private_data; > + int minsz; > + int ret = 0; > + > + if (ioctl == VFIO_DEVICE_QUERY_PLANE) { > + struct vfio_vgpu_query_plane plane_info; > + > + minsz = offsetofend(struct vfio_vgpu_query_plane, padding); > + if (copy_from_user(&plane_info, (void __user *)arg, minsz)) > + return -EFAULT; > + if (plane_info.argsz < minsz || plane_info.flags != 0) > + return -EINVAL; > + ret = intel_gvt_ops->vgpu_query_plane(vgpu, &plane_info); > + if (ret != 0) { > + gvt_vgpu_err("query plane failed:%d\n", ret); > + return -EINVAL; > + } > + return copy_to_user((void __user *)arg, &plane_info, minsz) ? > + -EFAULT : 0; > + } else if (ioctl == VFIO_DEVICE_CREATE_DMABUF) { > + struct vfio_vgpu_create_dmabuf dmabuf; > + > + minsz = offsetofend(struct vfio_vgpu_create_dmabuf, plane_id); > + if (copy_from_user(&dmabuf, (void __user *)arg, minsz)) > + return -EFAULT; > + if (dmabuf.argsz < minsz || dmabuf.flags != 0) > + return -EINVAL; > + > + ret = intel_gvt_ops->vgpu_create_dmabuf(vgpu, &dmabuf); > + if (ret != 0) > + return ret; > + > + return copy_to_user((void __user *)arg, &dmabuf, minsz) ? > + -EFAULT : 0; > + } else > + gvt_vgpu_err("unsupported mgr fd operation\n"); > + > + return -EINVAL; > +} > + > +static const struct file_operations intel_vgpu_dmabuf_mgr_fd_ops = { > + .release = intel_vgpu_dmabuf_mgr_fd_release, > + .unlocked_ioctl = intel_vgpu_dmabuf_mgr_fd_ioctl, > + .mmap = intel_vgpu_dmabuf_mgr_fd_mmap, > + .llseek = noop_llseek, > +}; > static int intel_vgpu_create(struct kobject *kobj, struct mdev_device *mdev) > { > struct intel_vgpu *vgpu = NULL; > @@ -1249,6 +1361,36 @@ static long intel_vgpu_ioctl(struct mdev_device *mdev, unsigned int cmd, > } else if (cmd == VFIO_DEVICE_RESET) { > intel_gvt_ops->vgpu_reset(vgpu); > return 0; > + } else if (cmd == VFIO_DEVICE_GET_FD) { > + int fd; > + u32 type; > + int ret; > + > + if (atomic_read(&vgpu->mgr_fd_opened)) { > + gvt_vgpu_err("mgr fd already opened\n"); > + return -EPERM; > + } Should check what's being asked for first, if other types are created that are not supported by kvmgt we should consistently return -EINVAL, not -EINVAL if DMABUF_MGR isn't already opened and -EPERM if it is. > + > + if (copy_from_user(&type, (void __user *)arg, sizeof(type))) > + return -EINVAL; > + if (type != VFIO_DEVICE_DMABUF_MGR_FD) > + return -EINVAL; > + > + ret = kvmgt_get_vfio_device(vgpu->handle); > + if (ret != 0) > + return ret; > + > + fd = anon_inode_getfd("intel-vgpu-dmabuf-mgr-fd", > + &intel_vgpu_dmabuf_mgr_fd_ops, > + vgpu, O_RDWR | O_CLOEXEC); > + if (fd < 0) { > + kvmgt_put_vfio_device(vgpu->handle); > + gvt_vgpu_err("create dmabuf mgr fd failed\n"); > + return -EINVAL; > + } > + atomic_inc(&vgpu->mgr_fd_opened); This doesn't seem like a super effective use of atomics, you could be sure to have only one open with a cmpxchg. > + > + return fd; > } > > return 0; > @@ -1612,6 +1754,9 @@ struct intel_gvt_mpt kvmgt_mpt = { > .write_gpa = kvmgt_write_gpa, > .gfn_to_mfn = kvmgt_gfn_to_pfn, > .set_opregion = kvmgt_set_opregion, > + .get_vfio_device = kvmgt_get_vfio_device, > + .put_vfio_device = kvmgt_put_vfio_device, > + > }; > EXPORT_SYMBOL_GPL(kvmgt_mpt); > > diff --git a/drivers/gpu/drm/i915/gvt/mpt.h b/drivers/gpu/drm/i915/gvt/mpt.h > index ab71300..1be961e 100644 > --- a/drivers/gpu/drm/i915/gvt/mpt.h > +++ b/drivers/gpu/drm/i915/gvt/mpt.h > @@ -308,4 +308,34 @@ static inline int intel_gvt_hypervisor_set_opregion(struct intel_vgpu *vgpu) > return intel_gvt_host.mpt->set_opregion(vgpu); > } > > +/** > + * intel_gvt_hypervisor_get_vfio_device - increase vfio device ref count > + * @vgpu: a vGPU > + * > + * Returns: > + * Zero on success, negative error code if failed. > + */ > +static inline int intel_gvt_hypervisor_get_vfio_device(struct intel_vgpu *vgpu) > +{ > + if (!intel_gvt_host.mpt->get_vfio_device) > + return 0; > + > + return intel_gvt_host.mpt->get_vfio_device(vgpu->handle); > +} > + > +/** > + * intel_gvt_hypervisor_put_vfio_device - decrease vfio device ref count > + * @vgpu: a vGPU > + * > + * Returns: > + * Zero on success, negative error code if failed. > + */ > +static inline void intel_gvt_hypervisor_put_vfio_device(struct intel_vgpu *vgpu) > +{ > + if (!intel_gvt_host.mpt->put_vfio_device) > + return; > + > + intel_gvt_host.mpt->put_vfio_device(vgpu->handle); > +} > + > #endif /* _GVT_MPT_H_ */ > diff --git a/drivers/gpu/drm/i915/gvt/vgpu.c b/drivers/gpu/drm/i915/gvt/vgpu.c > index 8e1d504..8747613 100644 > --- a/drivers/gpu/drm/i915/gvt/vgpu.c > +++ b/drivers/gpu/drm/i915/gvt/vgpu.c > @@ -346,6 +346,8 @@ static struct intel_vgpu *__intel_gvt_create_vgpu(struct intel_gvt *gvt, > vgpu->gvt = gvt; > vgpu->sched_ctl.weight = param->weight; > bitmap_zero(vgpu->tlb_handle_pending, I915_NUM_ENGINES); > + INIT_LIST_HEAD(&vgpu->dmabuf_obj_list_head); > + atomic_set(&vgpu->mgr_fd_opened, 0); > > intel_vgpu_init_cfg_space(vgpu, param->primary); >