From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 9BEBBC6379F for ; Mon, 13 Feb 2023 15:14:40 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 0C27410E60E; Mon, 13 Feb 2023 15:14:40 +0000 (UTC) Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by gabe.freedesktop.org (Postfix) with ESMTPS id 6ED7110E60E; Mon, 13 Feb 2023 15:14:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1676301258; x=1707837258; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=vYK+VzdGsyMdBFhy4eGViVnwSU0vUHFt71pZ3T0a0KY=; b=jKE6aa/HpFZzxkv0n9DTGbT3k2jzoRgMlvz3/WUo8MVU/wjuJRvnv5Z8 VpZa/iiW3ezs5Zy7sAmSY+KU5evrnwHS8gQD52h0RxHm1rnjWH3K/3WyD ING+RmKqw6RZBhwkYmdkmNXCEmaDW/5CvEBd+stOAHXpb7aw1Cz7XSjIT OF6S28b/5YknRdjBbaMeb7uVltDDmWt4QTA/5gSdXZwu484kzpxfCbd/6 kE4TEJOmk1SEWRM76vNQNQyy+MoiNUwiXOPetNZXrd4O2nuBMzP7lzome RIxq+9ZHJHpXkUFHCOcwTLzfAXo/59cMPh8R6XRwVvt7ZPKqjNXETSrhJ g==; X-IronPort-AV: E=McAfee;i="6500,9779,10620"; a="318931671" X-IronPort-AV: E=Sophos;i="5.97,294,1669104000"; d="scan'208";a="318931671" Received: from orsmga001.jf.intel.com ([10.7.209.18]) by orsmga101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Feb 2023 07:14:02 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6500,9779,10620"; a="701289695" X-IronPort-AV: E=Sophos;i="5.97,294,1669104000"; d="scan'208";a="701289695" Received: from 984fee00a4c6.jf.intel.com ([10.165.58.231]) by orsmga001.jf.intel.com with ESMTP; 13 Feb 2023 07:14:02 -0800 From: Yi Liu To: joro@8bytes.org, alex.williamson@redhat.com, jgg@nvidia.com, kevin.tian@intel.com, robin.murphy@arm.com Date: Mon, 13 Feb 2023 07:13:47 -0800 Message-Id: <20230213151348.56451-15-yi.l.liu@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230213151348.56451-1-yi.l.liu@intel.com> References: <20230213151348.56451-1-yi.l.liu@intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Subject: [Intel-gfx] [PATCH v3 14/15] vfio: Add ioctls for device cdev using iommufd X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-s390@vger.kernel.org, yi.l.liu@intel.com, yi.y.sun@linux.intel.com, kvm@vger.kernel.org, mjrosato@linux.ibm.com, jasowang@redhat.com, cohuck@redhat.com, peterx@redhat.com, eric.auger@redhat.com, nicolinc@nvidia.com, shameerali.kolothum.thodi@huawei.com, suravee.suthikulpanit@amd.com, chao.p.peng@linux.intel.com, lulu@redhat.com, intel-gvt-dev@lists.freedesktop.org, intel-gfx@lists.freedesktop.org Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" This adds three vfio device ioctls for userspace using iommufd to set up secure DMA context for device access. VFIO_DEVICE_BIND_IOMMUFD: bind device to an iommufd, hence gain DMA control provided by the iommufd. open_device op is called after bind_iommufd op. VFIO no iommu mode is indicated by passing a negative iommufd value. VFIO_DEVICE_ATTACH_IOMMUFD_PT: attach device to IOAS, hw_pagetable managed by iommufd. Attach can be undo by VFIO_DEVICE_DETACH_IOMMUFD_PT or device fd close. VFIO_DEVICE_DETACH_IOMMUFD_PT: detach device from the current attached IOAS or hw_pagetable managed by iommufd. Signed-off-by: Yi Liu --- drivers/vfio/device_cdev.c | 200 +++++++++++++++++++++++++++++++++++++ drivers/vfio/group.c | 27 +++++ drivers/vfio/vfio.h | 35 ++++++- drivers/vfio/vfio_main.c | 38 ++++++- include/linux/iommufd.h | 6 ++ include/uapi/linux/vfio.h | 86 ++++++++++++++++ 6 files changed, 387 insertions(+), 5 deletions(-) diff --git a/drivers/vfio/device_cdev.c b/drivers/vfio/device_cdev.c index 07869fde1c0c..e5297bf99cc4 100644 --- a/drivers/vfio/device_cdev.c +++ b/drivers/vfio/device_cdev.c @@ -3,6 +3,7 @@ * Copyright (c) 2023 Intel Corporation. */ #include +#include #include "vfio.h" @@ -46,6 +47,205 @@ int vfio_device_fops_open(struct inode *inode, struct file *filep) return ret; } +static void vfio_device_get_kvm_safe(struct vfio_device_file *df) +{ + spin_lock(&df->kvm_ref_lock); + if (!df->kvm) + goto unlock; + + _vfio_device_get_kvm_safe(df->device, df->kvm); + +unlock: + spin_unlock(&df->kvm_ref_lock); +} + +void vfio_device_cdev_close(struct vfio_device_file *df) +{ + struct vfio_device *device = df->device; + + mutex_lock(&device->dev_set->lock); + if (!device->open_count) { + mutex_unlock(&device->dev_set->lock); + return; + } + vfio_device_close(df); + vfio_device_put_kvm(device); + mutex_unlock(&device->dev_set->lock); + vfio_device_release_group(device); +} + +long vfio_device_ioctl_bind_iommufd(struct vfio_device_file *df, + unsigned long arg) +{ + struct vfio_device *device = df->device; + struct vfio_device_bind_iommufd bind; + struct iommufd_ctx *iommufd = NULL; + struct fd f; + unsigned long minsz; + int ret; + + minsz = offsetofend(struct vfio_device_bind_iommufd, out_devid); + + if (copy_from_user(&bind, (void __user *)arg, minsz)) + return -EFAULT; + + if (bind.argsz < minsz || bind.flags) + return -EINVAL; + + if (!device->ops->bind_iommufd) + return -ENODEV; + + ret = vfio_device_claim_group(device); + if (ret) + return ret; + + mutex_lock(&device->dev_set->lock); + /* + * If already been bound to an iommufd, or already set noiommu + * then fail it. + */ + if (df->iommufd || df->noiommu) { + ret = -EINVAL; + goto out_unlock; + } + + /* iommufd < 0 means noiommu mode */ + if (bind.iommufd < 0) { + if (!capable(CAP_SYS_RAWIO)) { + ret = -EPERM; + goto out_unlock; + } + df->noiommu = true; + } else { + f = fdget(bind.iommufd); + if (!f.file) { + ret = -EBADF; + goto out_unlock; + } + iommufd = iommufd_ctx_from_file(f.file); + if (IS_ERR(iommufd)) { + ret = PTR_ERR(iommufd); + goto out_put_file; + } + } + + /* + * Before the device open, get the KVM pointer currently + * associated with the device file (if there is) and obtain a + * reference. This reference is held until device closed. Save + * the pointer in the device for use by drivers. + */ + vfio_device_get_kvm_safe(df); + + df->iommufd = iommufd; + ret = vfio_device_open(df, &bind.out_devid, NULL); + if (ret) + goto out_put_kvm; + + ret = copy_to_user((void __user *)arg + + offsetofend(struct vfio_device_bind_iommufd, iommufd), + &bind.out_devid, + sizeof(bind.out_devid)) ? -EFAULT : 0; + if (ret) + goto out_close_device; + + if (iommufd) + fdput(f); + else if (df->noiommu) + dev_warn(device->dev, "vfio-noiommu device used by user " + "(%s:%d)\n", current->comm, task_pid_nr(current)); + mutex_unlock(&device->dev_set->lock); + return 0; + +out_close_device: + vfio_device_close(df); +out_put_kvm: + df->iommufd = NULL; + df->noiommu = false; + vfio_device_put_kvm(device); +out_put_file: + if (iommufd) + fdput(f); +out_unlock: + mutex_unlock(&device->dev_set->lock); + vfio_device_release_group(device); + return ret; +} + +int vfio_ioctl_device_attach(struct vfio_device_file *df, + void __user *arg) +{ + struct vfio_device *device = df->device; + struct vfio_device_attach_iommufd_pt attach; + unsigned long minsz; + int ret; + + minsz = offsetofend(struct vfio_device_attach_iommufd_pt, pt_id); + + if (copy_from_user(&attach, (void __user *)arg, minsz)) + return -EFAULT; + + if (attach.argsz < minsz || attach.flags || + attach.pt_id == IOMMUFD_INVALID_ID) + return -EINVAL; + + if (!device->ops->bind_iommufd) + return -ENODEV; + + mutex_lock(&device->dev_set->lock); + if (df->noiommu) { + ret = -EINVAL; + goto out_unlock; + } + + ret = device->ops->attach_ioas(device, &attach.pt_id); + if (ret) + goto out_unlock; + + ret = copy_to_user((void __user *)arg + + offsetofend(struct vfio_device_attach_iommufd_pt, flags), + &attach.pt_id, + sizeof(attach.pt_id)) ? -EFAULT : 0; + if (ret) + goto out_detach; + mutex_unlock(&device->dev_set->lock); + return 0; + +out_detach: + device->ops->detach_ioas(device); +out_unlock: + mutex_unlock(&device->dev_set->lock); + return ret; +} + +int vfio_ioctl_device_detach(struct vfio_device_file *df, + void __user *arg) +{ + struct vfio_device *device = df->device; + struct vfio_device_detach_iommufd_pt detach; + unsigned long minsz; + + minsz = offsetofend(struct vfio_device_detach_iommufd_pt, flags); + + if (copy_from_user(&detach, (void __user *)arg, minsz)) + return -EFAULT; + + if (detach.argsz < minsz || detach.flags) + return -EINVAL; + + if (!device->ops->bind_iommufd) + return -ENODEV; + + mutex_lock(&device->dev_set->lock); + if (df->noiommu) { + mutex_unlock(&device->dev_set->lock); + return -EINVAL; + } + device->ops->detach_ioas(device); + mutex_unlock(&device->dev_set->lock); + return 0; +} + static char *vfio_device_devnode(const struct device *dev, umode_t *mode) { return kasprintf(GFP_KERNEL, "vfio/devices/%s", dev_name(dev)); diff --git a/drivers/vfio/group.c b/drivers/vfio/group.c index f3f5f4589cdd..8ee06d8b17fa 100644 --- a/drivers/vfio/group.c +++ b/drivers/vfio/group.c @@ -381,6 +381,33 @@ static long vfio_group_fops_unl_ioctl(struct file *filep, } } +int vfio_device_claim_group(struct vfio_device *device) +{ + struct vfio_group *group = device->group; + int ret = 0; + + mutex_lock(&group->group_lock); + if (group->opened_file) { + ret = -EBUSY; + goto out_unlock; + } + + group->cdev_device_open_cnt++; + +out_unlock: + mutex_unlock(&group->group_lock); + return ret; +} + +void vfio_device_release_group(struct vfio_device *device) +{ + struct vfio_group *group = device->group; + + mutex_lock(&group->group_lock); + group->cdev_device_open_cnt--; + mutex_unlock(&group->group_lock); +} + static int vfio_group_fops_open(struct inode *inode, struct file *filep) { struct vfio_group *group = diff --git a/drivers/vfio/vfio.h b/drivers/vfio/vfio.h index be93a1c953f8..421492518ab5 100644 --- a/drivers/vfio/vfio.h +++ b/drivers/vfio/vfio.h @@ -23,7 +23,9 @@ struct vfio_device_file { bool access_granted; spinlock_t kvm_ref_lock; /* protect kvm field */ struct kvm *kvm; - struct iommufd_ctx *iommufd; /* protected by struct vfio_device_set::lock */ + /* protected by struct vfio_device_set::lock */ + struct iommufd_ctx *iommufd; + bool noiommu; }; void vfio_device_put_registration(struct vfio_device *device); @@ -89,6 +91,8 @@ struct vfio_group { unsigned int cdev_device_open_cnt; }; +int vfio_device_claim_group(struct vfio_device *device); +void vfio_device_release_group(struct vfio_device *device); int vfio_device_set_group(struct vfio_device *device, enum vfio_group_type type); void vfio_device_remove_group(struct vfio_device *device); @@ -247,6 +251,13 @@ static inline void vfio_iommufd_unbind(struct vfio_device *device) #if IS_ENABLED(CONFIG_VFIO_DEVICE_CDEV) void vfio_init_device_cdev(struct vfio_device *device); int vfio_device_fops_open(struct inode *inode, struct file *filep); +void vfio_device_cdev_close(struct vfio_device_file *df); +long vfio_device_ioctl_bind_iommufd(struct vfio_device_file *df, + unsigned long arg); +int vfio_ioctl_device_attach(struct vfio_device_file *df, + void __user *arg); +int vfio_ioctl_device_detach(struct vfio_device_file *df, + void __user *arg); int vfio_cdev_init(struct class *device_class); void vfio_cdev_cleanup(void); #else @@ -260,6 +271,28 @@ static inline int vfio_device_fops_open(struct inode *inode, return 0; } +static inline void vfio_device_cdev_close(struct vfio_device_file *df) +{ +} + +static inline long vfio_device_ioctl_bind_iommufd(struct vfio_device_file *df, + unsigned long arg) +{ + return -EOPNOTSUPP; +} + +static inline int vfio_ioctl_device_attach(struct vfio_device_file *df, + void __user *arg) +{ + return -EOPNOTSUPP; +} + +static inline int vfio_ioctl_device_detach(struct vfio_device_file *df, + void __user *arg) +{ + return -EOPNOTSUPP; +} + static inline int vfio_cdev_init(struct class *device_class) { return 0; diff --git a/drivers/vfio/vfio_main.c b/drivers/vfio/vfio_main.c index a7eb2727c613..933319083282 100644 --- a/drivers/vfio/vfio_main.c +++ b/drivers/vfio/vfio_main.c @@ -37,6 +37,7 @@ #include #include #include +#include #include "vfio.h" #define DRIVER_VERSION "0.3" @@ -441,16 +442,32 @@ static int vfio_device_first_open(struct vfio_device_file *df, { struct vfio_device *device = df->device; struct iommufd_ctx *iommufd = df->iommufd; - int ret; + int ret = 0; lockdep_assert_held(&device->dev_set->lock); + if (WARN_ON(iommufd && df->noiommu)) + return -EINVAL; + if (!try_module_get(device->dev->driver->owner)) return -ENODEV; + /* + * For group/container path, iommufd pointer is NULL when comes + * into this helper. Its noiommu support is in container.c. + * + * For iommufd compat mode, iommufd pointer here is a valid value. + * Its noiommu support is in vfio_iommufd_bind(). + * + * For device cdev path, iommufd pointer here is a valid value for + * normal cases, but it is NULL if it's noiommu. To differentiate + * the noiommu from the group/container path which also passes NULL + * iommufd pointer in, check df->noiommu which is set only in the + * cdev path. + */ if (iommufd) ret = vfio_iommufd_bind(device, iommufd, dev_id, pt_id); - else + else if (!df->noiommu) ret = vfio_device_group_use_iommu(device); if (ret) goto err_module_put; @@ -465,7 +482,7 @@ static int vfio_device_first_open(struct vfio_device_file *df, err_unuse_iommu: if (iommufd) vfio_iommufd_unbind(device); - else + else if (!df->noiommu) vfio_device_group_unuse_iommu(device); err_module_put: module_put(device->dev->driver->owner); @@ -483,7 +500,7 @@ static void vfio_device_last_close(struct vfio_device_file *df) device->ops->close_device(device); if (iommufd) vfio_iommufd_unbind(device); - else + else if (!df->noiommu) vfio_device_group_unuse_iommu(device); module_put(device->dev->driver->owner); } @@ -582,6 +599,8 @@ static int vfio_device_fops_release(struct inode *inode, struct file *filep) */ if (!df->is_cdev_device) vfio_device_group_close(df); + else + vfio_device_cdev_close(df); vfio_device_put_registration(device); @@ -1156,6 +1175,9 @@ static long vfio_device_fops_unl_ioctl(struct file *filep, bool access; int ret; + if (cmd == VFIO_DEVICE_BIND_IOMMUFD) + return vfio_device_ioctl_bind_iommufd(df, arg); + /* Paired with smp_store_release() in vfio_device_open() */ access = smp_load_acquire(&df->access_granted); if (!access) @@ -1170,6 +1192,14 @@ static long vfio_device_fops_unl_ioctl(struct file *filep, ret = vfio_ioctl_device_feature(device, (void __user *)arg); break; + case VFIO_DEVICE_ATTACH_IOMMUFD_PT: + ret = vfio_ioctl_device_attach(df, (void __user *)arg); + break; + + case VFIO_DEVICE_DETACH_IOMMUFD_PT: + ret = vfio_ioctl_device_detach(df, (void __user *)arg); + break; + default: if (unlikely(!device->ops->ioctl)) ret = -EINVAL; diff --git a/include/linux/iommufd.h b/include/linux/iommufd.h index 650d45629647..9672cf839687 100644 --- a/include/linux/iommufd.h +++ b/include/linux/iommufd.h @@ -17,6 +17,12 @@ struct iommufd_ctx; struct iommufd_access; struct file; +/* + * iommufd core init xarray with flags==XA_FLAGS_ALLOC1, so valid + * ID starts from 1. + */ +#define IOMMUFD_INVALID_ID 0 + struct iommufd_device *iommufd_device_bind(struct iommufd_ctx *ictx, struct device *dev, u32 *id); void iommufd_device_unbind(struct iommufd_device *idev); diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h index 0552e8dcf0cb..026af52cf22e 100644 --- a/include/uapi/linux/vfio.h +++ b/include/uapi/linux/vfio.h @@ -194,6 +194,92 @@ struct vfio_group_status { /* --------------- IOCTLs for DEVICE file descriptors --------------- */ +/* + * VFIO_DEVICE_BIND_IOMMUFD - _IOR(VFIO_TYPE, VFIO_BASE + 19, + * struct vfio_device_bind_iommufd) + * + * Bind a vfio_device to the specified iommufd. + * + * The user should provide a device cookie when calling this ioctl. The + * cookie is carried only in event e.g. I/O fault reported to userspace + * via iommufd. The user should use devid returned by this ioctl to mark + * the target device in other ioctls (e.g. capability query via iommufd). + * + * User is not allowed to access the device before the binding operation + * is completed. + * + * Unbind is automatically conducted when device fd is closed. + * + * @argsz: user filled size of this data. + * @flags: reserved for future extension. + * @dev_cookie: a per device cookie provided by userspace. + * @iommufd: iommufd to bind. a negative value means noiommu. + * @out_devid: the device id generated by this bind. + * + * Return: 0 on success, -errno on failure. + */ +struct vfio_device_bind_iommufd { + __u32 argsz; + __u32 flags; + __aligned_u64 dev_cookie; + __s32 iommufd; + __u32 out_devid; +}; + +#define VFIO_DEVICE_BIND_IOMMUFD _IO(VFIO_TYPE, VFIO_BASE + 19) + +/* + * VFIO_DEVICE_ATTACH_IOMMUFD_PT - _IOW(VFIO_TYPE, VFIO_BASE + 20, + * struct vfio_device_attach_iommufd_pt) + * + * Attach a vfio device to an iommufd address space specified by IOAS + * id or hw_pagetable (hwpt) id. + * + * Available only after a device has been bound to iommufd via + * VFIO_DEVICE_BIND_IOMMUFD + * + * Undo by VFIO_DEVICE_DETACH_IOMMUFD_PT or device fd close. + * + * @argsz: user filled size of this data. + * @flags: must be 0. + * @pt_id: Input the target id which can represent an ioas or a hwpt + * allocated via iommufd subsystem. + * Output the attached hwpt id which could be the specified + * hwpt itself or a hwpt automatically created for the + * specified ioas by kernel during the attachment. + * + * Return: 0 on success, -errno on failure. + */ +struct vfio_device_attach_iommufd_pt { + __u32 argsz; + __u32 flags; + __u32 pt_id; +}; + +#define VFIO_DEVICE_ATTACH_IOMMUFD_PT _IO(VFIO_TYPE, VFIO_BASE + 20) + +/* + * VFIO_DEVICE_DETACH_IOMMUFD_PT - _IOW(VFIO_TYPE, VFIO_BASE + 21, + * struct vfio_device_detach_iommufd_pt) + * + * Detach a vfio device from the iommufd address space it has been + * attached to. After it, device should be in a blocking DMA state. + * + * Available only after a device has been bound to iommufd via + * VFIO_DEVICE_BIND_IOMMUFD + * + * @argsz: user filled size of this data. + * @flags: must be 0. + * + * Return: 0 on success, -errno on failure. + */ +struct vfio_device_detach_iommufd_pt { + __u32 argsz; + __u32 flags; +}; + +#define VFIO_DEVICE_DETACH_IOMMUFD_PT _IO(VFIO_TYPE, VFIO_BASE + 21) + /** * VFIO_DEVICE_GET_INFO - _IOR(VFIO_TYPE, VFIO_BASE + 7, * struct vfio_device_info) -- 2.34.1 From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 90887C64ED6 for ; Mon, 13 Feb 2023 15:16:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230319AbjBMPQA (ORCPT ); Mon, 13 Feb 2023 10:16:00 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54540 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231130AbjBMPPp (ORCPT ); Mon, 13 Feb 2023 10:15:45 -0500 Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B23B41EBC6; Mon, 13 Feb 2023 07:15:19 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1676301319; x=1707837319; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=vYK+VzdGsyMdBFhy4eGViVnwSU0vUHFt71pZ3T0a0KY=; b=oAl9iiwZCsMHFMUpWHy2m0kOBem/+82MhJ+POWf2wyWDMcAdrZFaxJTO b2UGTj6pO5NoVphXHf1qvIPU2vhZG4I96RNXKnu9jH9TYyAf7sReWLd7x u5epR/lMByhKHnKtQBQB0l0iO7WVjY3ndgrdDvonusP9wjFxXlhqbItur YeiZRtotDC3m7heiTqPMfGaFNuZrW0QcAZy8zfK2Tu1pkLPKfc7oQxVGi JoveVLY0syTA0hoz5n62KQn2K1eLalcSJX7cSZ60I7uW8fG0R4fMemB72 zbi/fKhbqz75rAr4z8HpiZVgVyOAcxZ2PBXHXNOysUQq6q7U6BKIUCVGY Q==; X-IronPort-AV: E=McAfee;i="6500,9779,10620"; a="318931667" X-IronPort-AV: E=Sophos;i="5.97,294,1669104000"; d="scan'208";a="318931667" Received: from orsmga001.jf.intel.com ([10.7.209.18]) by orsmga101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Feb 2023 07:14:02 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6500,9779,10620"; a="701289695" X-IronPort-AV: E=Sophos;i="5.97,294,1669104000"; d="scan'208";a="701289695" Received: from 984fee00a4c6.jf.intel.com ([10.165.58.231]) by orsmga001.jf.intel.com with ESMTP; 13 Feb 2023 07:14:02 -0800 From: Yi Liu To: joro@8bytes.org, alex.williamson@redhat.com, jgg@nvidia.com, kevin.tian@intel.com, robin.murphy@arm.com Cc: cohuck@redhat.com, eric.auger@redhat.com, nicolinc@nvidia.com, kvm@vger.kernel.org, mjrosato@linux.ibm.com, chao.p.peng@linux.intel.com, yi.l.liu@intel.com, yi.y.sun@linux.intel.com, peterx@redhat.com, jasowang@redhat.com, shameerali.kolothum.thodi@huawei.com, lulu@redhat.com, suravee.suthikulpanit@amd.com, intel-gvt-dev@lists.freedesktop.org, intel-gfx@lists.freedesktop.org, linux-s390@vger.kernel.org Subject: [PATCH v3 14/15] vfio: Add ioctls for device cdev using iommufd Date: Mon, 13 Feb 2023 07:13:47 -0800 Message-Id: <20230213151348.56451-15-yi.l.liu@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230213151348.56451-1-yi.l.liu@intel.com> References: <20230213151348.56451-1-yi.l.liu@intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-s390@vger.kernel.org This adds three vfio device ioctls for userspace using iommufd to set up secure DMA context for device access. VFIO_DEVICE_BIND_IOMMUFD: bind device to an iommufd, hence gain DMA control provided by the iommufd. open_device op is called after bind_iommufd op. VFIO no iommu mode is indicated by passing a negative iommufd value. VFIO_DEVICE_ATTACH_IOMMUFD_PT: attach device to IOAS, hw_pagetable managed by iommufd. Attach can be undo by VFIO_DEVICE_DETACH_IOMMUFD_PT or device fd close. VFIO_DEVICE_DETACH_IOMMUFD_PT: detach device from the current attached IOAS or hw_pagetable managed by iommufd. Signed-off-by: Yi Liu --- drivers/vfio/device_cdev.c | 200 +++++++++++++++++++++++++++++++++++++ drivers/vfio/group.c | 27 +++++ drivers/vfio/vfio.h | 35 ++++++- drivers/vfio/vfio_main.c | 38 ++++++- include/linux/iommufd.h | 6 ++ include/uapi/linux/vfio.h | 86 ++++++++++++++++ 6 files changed, 387 insertions(+), 5 deletions(-) diff --git a/drivers/vfio/device_cdev.c b/drivers/vfio/device_cdev.c index 07869fde1c0c..e5297bf99cc4 100644 --- a/drivers/vfio/device_cdev.c +++ b/drivers/vfio/device_cdev.c @@ -3,6 +3,7 @@ * Copyright (c) 2023 Intel Corporation. */ #include +#include #include "vfio.h" @@ -46,6 +47,205 @@ int vfio_device_fops_open(struct inode *inode, struct file *filep) return ret; } +static void vfio_device_get_kvm_safe(struct vfio_device_file *df) +{ + spin_lock(&df->kvm_ref_lock); + if (!df->kvm) + goto unlock; + + _vfio_device_get_kvm_safe(df->device, df->kvm); + +unlock: + spin_unlock(&df->kvm_ref_lock); +} + +void vfio_device_cdev_close(struct vfio_device_file *df) +{ + struct vfio_device *device = df->device; + + mutex_lock(&device->dev_set->lock); + if (!device->open_count) { + mutex_unlock(&device->dev_set->lock); + return; + } + vfio_device_close(df); + vfio_device_put_kvm(device); + mutex_unlock(&device->dev_set->lock); + vfio_device_release_group(device); +} + +long vfio_device_ioctl_bind_iommufd(struct vfio_device_file *df, + unsigned long arg) +{ + struct vfio_device *device = df->device; + struct vfio_device_bind_iommufd bind; + struct iommufd_ctx *iommufd = NULL; + struct fd f; + unsigned long minsz; + int ret; + + minsz = offsetofend(struct vfio_device_bind_iommufd, out_devid); + + if (copy_from_user(&bind, (void __user *)arg, minsz)) + return -EFAULT; + + if (bind.argsz < minsz || bind.flags) + return -EINVAL; + + if (!device->ops->bind_iommufd) + return -ENODEV; + + ret = vfio_device_claim_group(device); + if (ret) + return ret; + + mutex_lock(&device->dev_set->lock); + /* + * If already been bound to an iommufd, or already set noiommu + * then fail it. + */ + if (df->iommufd || df->noiommu) { + ret = -EINVAL; + goto out_unlock; + } + + /* iommufd < 0 means noiommu mode */ + if (bind.iommufd < 0) { + if (!capable(CAP_SYS_RAWIO)) { + ret = -EPERM; + goto out_unlock; + } + df->noiommu = true; + } else { + f = fdget(bind.iommufd); + if (!f.file) { + ret = -EBADF; + goto out_unlock; + } + iommufd = iommufd_ctx_from_file(f.file); + if (IS_ERR(iommufd)) { + ret = PTR_ERR(iommufd); + goto out_put_file; + } + } + + /* + * Before the device open, get the KVM pointer currently + * associated with the device file (if there is) and obtain a + * reference. This reference is held until device closed. Save + * the pointer in the device for use by drivers. + */ + vfio_device_get_kvm_safe(df); + + df->iommufd = iommufd; + ret = vfio_device_open(df, &bind.out_devid, NULL); + if (ret) + goto out_put_kvm; + + ret = copy_to_user((void __user *)arg + + offsetofend(struct vfio_device_bind_iommufd, iommufd), + &bind.out_devid, + sizeof(bind.out_devid)) ? -EFAULT : 0; + if (ret) + goto out_close_device; + + if (iommufd) + fdput(f); + else if (df->noiommu) + dev_warn(device->dev, "vfio-noiommu device used by user " + "(%s:%d)\n", current->comm, task_pid_nr(current)); + mutex_unlock(&device->dev_set->lock); + return 0; + +out_close_device: + vfio_device_close(df); +out_put_kvm: + df->iommufd = NULL; + df->noiommu = false; + vfio_device_put_kvm(device); +out_put_file: + if (iommufd) + fdput(f); +out_unlock: + mutex_unlock(&device->dev_set->lock); + vfio_device_release_group(device); + return ret; +} + +int vfio_ioctl_device_attach(struct vfio_device_file *df, + void __user *arg) +{ + struct vfio_device *device = df->device; + struct vfio_device_attach_iommufd_pt attach; + unsigned long minsz; + int ret; + + minsz = offsetofend(struct vfio_device_attach_iommufd_pt, pt_id); + + if (copy_from_user(&attach, (void __user *)arg, minsz)) + return -EFAULT; + + if (attach.argsz < minsz || attach.flags || + attach.pt_id == IOMMUFD_INVALID_ID) + return -EINVAL; + + if (!device->ops->bind_iommufd) + return -ENODEV; + + mutex_lock(&device->dev_set->lock); + if (df->noiommu) { + ret = -EINVAL; + goto out_unlock; + } + + ret = device->ops->attach_ioas(device, &attach.pt_id); + if (ret) + goto out_unlock; + + ret = copy_to_user((void __user *)arg + + offsetofend(struct vfio_device_attach_iommufd_pt, flags), + &attach.pt_id, + sizeof(attach.pt_id)) ? -EFAULT : 0; + if (ret) + goto out_detach; + mutex_unlock(&device->dev_set->lock); + return 0; + +out_detach: + device->ops->detach_ioas(device); +out_unlock: + mutex_unlock(&device->dev_set->lock); + return ret; +} + +int vfio_ioctl_device_detach(struct vfio_device_file *df, + void __user *arg) +{ + struct vfio_device *device = df->device; + struct vfio_device_detach_iommufd_pt detach; + unsigned long minsz; + + minsz = offsetofend(struct vfio_device_detach_iommufd_pt, flags); + + if (copy_from_user(&detach, (void __user *)arg, minsz)) + return -EFAULT; + + if (detach.argsz < minsz || detach.flags) + return -EINVAL; + + if (!device->ops->bind_iommufd) + return -ENODEV; + + mutex_lock(&device->dev_set->lock); + if (df->noiommu) { + mutex_unlock(&device->dev_set->lock); + return -EINVAL; + } + device->ops->detach_ioas(device); + mutex_unlock(&device->dev_set->lock); + return 0; +} + static char *vfio_device_devnode(const struct device *dev, umode_t *mode) { return kasprintf(GFP_KERNEL, "vfio/devices/%s", dev_name(dev)); diff --git a/drivers/vfio/group.c b/drivers/vfio/group.c index f3f5f4589cdd..8ee06d8b17fa 100644 --- a/drivers/vfio/group.c +++ b/drivers/vfio/group.c @@ -381,6 +381,33 @@ static long vfio_group_fops_unl_ioctl(struct file *filep, } } +int vfio_device_claim_group(struct vfio_device *device) +{ + struct vfio_group *group = device->group; + int ret = 0; + + mutex_lock(&group->group_lock); + if (group->opened_file) { + ret = -EBUSY; + goto out_unlock; + } + + group->cdev_device_open_cnt++; + +out_unlock: + mutex_unlock(&group->group_lock); + return ret; +} + +void vfio_device_release_group(struct vfio_device *device) +{ + struct vfio_group *group = device->group; + + mutex_lock(&group->group_lock); + group->cdev_device_open_cnt--; + mutex_unlock(&group->group_lock); +} + static int vfio_group_fops_open(struct inode *inode, struct file *filep) { struct vfio_group *group = diff --git a/drivers/vfio/vfio.h b/drivers/vfio/vfio.h index be93a1c953f8..421492518ab5 100644 --- a/drivers/vfio/vfio.h +++ b/drivers/vfio/vfio.h @@ -23,7 +23,9 @@ struct vfio_device_file { bool access_granted; spinlock_t kvm_ref_lock; /* protect kvm field */ struct kvm *kvm; - struct iommufd_ctx *iommufd; /* protected by struct vfio_device_set::lock */ + /* protected by struct vfio_device_set::lock */ + struct iommufd_ctx *iommufd; + bool noiommu; }; void vfio_device_put_registration(struct vfio_device *device); @@ -89,6 +91,8 @@ struct vfio_group { unsigned int cdev_device_open_cnt; }; +int vfio_device_claim_group(struct vfio_device *device); +void vfio_device_release_group(struct vfio_device *device); int vfio_device_set_group(struct vfio_device *device, enum vfio_group_type type); void vfio_device_remove_group(struct vfio_device *device); @@ -247,6 +251,13 @@ static inline void vfio_iommufd_unbind(struct vfio_device *device) #if IS_ENABLED(CONFIG_VFIO_DEVICE_CDEV) void vfio_init_device_cdev(struct vfio_device *device); int vfio_device_fops_open(struct inode *inode, struct file *filep); +void vfio_device_cdev_close(struct vfio_device_file *df); +long vfio_device_ioctl_bind_iommufd(struct vfio_device_file *df, + unsigned long arg); +int vfio_ioctl_device_attach(struct vfio_device_file *df, + void __user *arg); +int vfio_ioctl_device_detach(struct vfio_device_file *df, + void __user *arg); int vfio_cdev_init(struct class *device_class); void vfio_cdev_cleanup(void); #else @@ -260,6 +271,28 @@ static inline int vfio_device_fops_open(struct inode *inode, return 0; } +static inline void vfio_device_cdev_close(struct vfio_device_file *df) +{ +} + +static inline long vfio_device_ioctl_bind_iommufd(struct vfio_device_file *df, + unsigned long arg) +{ + return -EOPNOTSUPP; +} + +static inline int vfio_ioctl_device_attach(struct vfio_device_file *df, + void __user *arg) +{ + return -EOPNOTSUPP; +} + +static inline int vfio_ioctl_device_detach(struct vfio_device_file *df, + void __user *arg) +{ + return -EOPNOTSUPP; +} + static inline int vfio_cdev_init(struct class *device_class) { return 0; diff --git a/drivers/vfio/vfio_main.c b/drivers/vfio/vfio_main.c index a7eb2727c613..933319083282 100644 --- a/drivers/vfio/vfio_main.c +++ b/drivers/vfio/vfio_main.c @@ -37,6 +37,7 @@ #include #include #include +#include #include "vfio.h" #define DRIVER_VERSION "0.3" @@ -441,16 +442,32 @@ static int vfio_device_first_open(struct vfio_device_file *df, { struct vfio_device *device = df->device; struct iommufd_ctx *iommufd = df->iommufd; - int ret; + int ret = 0; lockdep_assert_held(&device->dev_set->lock); + if (WARN_ON(iommufd && df->noiommu)) + return -EINVAL; + if (!try_module_get(device->dev->driver->owner)) return -ENODEV; + /* + * For group/container path, iommufd pointer is NULL when comes + * into this helper. Its noiommu support is in container.c. + * + * For iommufd compat mode, iommufd pointer here is a valid value. + * Its noiommu support is in vfio_iommufd_bind(). + * + * For device cdev path, iommufd pointer here is a valid value for + * normal cases, but it is NULL if it's noiommu. To differentiate + * the noiommu from the group/container path which also passes NULL + * iommufd pointer in, check df->noiommu which is set only in the + * cdev path. + */ if (iommufd) ret = vfio_iommufd_bind(device, iommufd, dev_id, pt_id); - else + else if (!df->noiommu) ret = vfio_device_group_use_iommu(device); if (ret) goto err_module_put; @@ -465,7 +482,7 @@ static int vfio_device_first_open(struct vfio_device_file *df, err_unuse_iommu: if (iommufd) vfio_iommufd_unbind(device); - else + else if (!df->noiommu) vfio_device_group_unuse_iommu(device); err_module_put: module_put(device->dev->driver->owner); @@ -483,7 +500,7 @@ static void vfio_device_last_close(struct vfio_device_file *df) device->ops->close_device(device); if (iommufd) vfio_iommufd_unbind(device); - else + else if (!df->noiommu) vfio_device_group_unuse_iommu(device); module_put(device->dev->driver->owner); } @@ -582,6 +599,8 @@ static int vfio_device_fops_release(struct inode *inode, struct file *filep) */ if (!df->is_cdev_device) vfio_device_group_close(df); + else + vfio_device_cdev_close(df); vfio_device_put_registration(device); @@ -1156,6 +1175,9 @@ static long vfio_device_fops_unl_ioctl(struct file *filep, bool access; int ret; + if (cmd == VFIO_DEVICE_BIND_IOMMUFD) + return vfio_device_ioctl_bind_iommufd(df, arg); + /* Paired with smp_store_release() in vfio_device_open() */ access = smp_load_acquire(&df->access_granted); if (!access) @@ -1170,6 +1192,14 @@ static long vfio_device_fops_unl_ioctl(struct file *filep, ret = vfio_ioctl_device_feature(device, (void __user *)arg); break; + case VFIO_DEVICE_ATTACH_IOMMUFD_PT: + ret = vfio_ioctl_device_attach(df, (void __user *)arg); + break; + + case VFIO_DEVICE_DETACH_IOMMUFD_PT: + ret = vfio_ioctl_device_detach(df, (void __user *)arg); + break; + default: if (unlikely(!device->ops->ioctl)) ret = -EINVAL; diff --git a/include/linux/iommufd.h b/include/linux/iommufd.h index 650d45629647..9672cf839687 100644 --- a/include/linux/iommufd.h +++ b/include/linux/iommufd.h @@ -17,6 +17,12 @@ struct iommufd_ctx; struct iommufd_access; struct file; +/* + * iommufd core init xarray with flags==XA_FLAGS_ALLOC1, so valid + * ID starts from 1. + */ +#define IOMMUFD_INVALID_ID 0 + struct iommufd_device *iommufd_device_bind(struct iommufd_ctx *ictx, struct device *dev, u32 *id); void iommufd_device_unbind(struct iommufd_device *idev); diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h index 0552e8dcf0cb..026af52cf22e 100644 --- a/include/uapi/linux/vfio.h +++ b/include/uapi/linux/vfio.h @@ -194,6 +194,92 @@ struct vfio_group_status { /* --------------- IOCTLs for DEVICE file descriptors --------------- */ +/* + * VFIO_DEVICE_BIND_IOMMUFD - _IOR(VFIO_TYPE, VFIO_BASE + 19, + * struct vfio_device_bind_iommufd) + * + * Bind a vfio_device to the specified iommufd. + * + * The user should provide a device cookie when calling this ioctl. The + * cookie is carried only in event e.g. I/O fault reported to userspace + * via iommufd. The user should use devid returned by this ioctl to mark + * the target device in other ioctls (e.g. capability query via iommufd). + * + * User is not allowed to access the device before the binding operation + * is completed. + * + * Unbind is automatically conducted when device fd is closed. + * + * @argsz: user filled size of this data. + * @flags: reserved for future extension. + * @dev_cookie: a per device cookie provided by userspace. + * @iommufd: iommufd to bind. a negative value means noiommu. + * @out_devid: the device id generated by this bind. + * + * Return: 0 on success, -errno on failure. + */ +struct vfio_device_bind_iommufd { + __u32 argsz; + __u32 flags; + __aligned_u64 dev_cookie; + __s32 iommufd; + __u32 out_devid; +}; + +#define VFIO_DEVICE_BIND_IOMMUFD _IO(VFIO_TYPE, VFIO_BASE + 19) + +/* + * VFIO_DEVICE_ATTACH_IOMMUFD_PT - _IOW(VFIO_TYPE, VFIO_BASE + 20, + * struct vfio_device_attach_iommufd_pt) + * + * Attach a vfio device to an iommufd address space specified by IOAS + * id or hw_pagetable (hwpt) id. + * + * Available only after a device has been bound to iommufd via + * VFIO_DEVICE_BIND_IOMMUFD + * + * Undo by VFIO_DEVICE_DETACH_IOMMUFD_PT or device fd close. + * + * @argsz: user filled size of this data. + * @flags: must be 0. + * @pt_id: Input the target id which can represent an ioas or a hwpt + * allocated via iommufd subsystem. + * Output the attached hwpt id which could be the specified + * hwpt itself or a hwpt automatically created for the + * specified ioas by kernel during the attachment. + * + * Return: 0 on success, -errno on failure. + */ +struct vfio_device_attach_iommufd_pt { + __u32 argsz; + __u32 flags; + __u32 pt_id; +}; + +#define VFIO_DEVICE_ATTACH_IOMMUFD_PT _IO(VFIO_TYPE, VFIO_BASE + 20) + +/* + * VFIO_DEVICE_DETACH_IOMMUFD_PT - _IOW(VFIO_TYPE, VFIO_BASE + 21, + * struct vfio_device_detach_iommufd_pt) + * + * Detach a vfio device from the iommufd address space it has been + * attached to. After it, device should be in a blocking DMA state. + * + * Available only after a device has been bound to iommufd via + * VFIO_DEVICE_BIND_IOMMUFD + * + * @argsz: user filled size of this data. + * @flags: must be 0. + * + * Return: 0 on success, -errno on failure. + */ +struct vfio_device_detach_iommufd_pt { + __u32 argsz; + __u32 flags; +}; + +#define VFIO_DEVICE_DETACH_IOMMUFD_PT _IO(VFIO_TYPE, VFIO_BASE + 21) + /** * VFIO_DEVICE_GET_INFO - _IOR(VFIO_TYPE, VFIO_BASE + 7, * struct vfio_device_info) -- 2.34.1