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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?D7i9q7GnDxnwcsHk/I/MPSJJ5cAv8h9CL94aKKtFDidJMUuDCLS2vRsSC22O?= =?us-ascii?Q?oOy6kzwLekfH9ftNsL1bPxY9ixr9tt7fh7N0+vaHiR031lhP33/b9wcsoy9N?= =?us-ascii?Q?bKjgL5ENs5HztQp/l4+RwZ19eWc4x1ZCEr+VSoce3hxLwAnxoWbW9OPkT43w?= =?us-ascii?Q?XxMUkckfblE37xZqmUuofN6x3M1fAlyJ/ACkjYi/PXiO0EWG4w29mu7ejHXH?= =?us-ascii?Q?NL7D+U1ke+k0On6waNtxiYuPUqBbP3oQtFMAxVADlQW+SJJ/sAxYW7iYEZZo?= =?us-ascii?Q?7g5+vOWUD6XZDpEOKP3QwnlUBLsdRlTPxFoUhNUi5djYDLwIvnHUCuWmevMe?= =?us-ascii?Q?bXvfgYsB0VoZarUqcDCushC12EtSF1ETILPmGwgKc6aThi6H+jxCIhmLWDVF?= =?us-ascii?Q?QVWYSbJ5GJcNUriokPOmYxEHbQZEx25+cXjbNlyFMZuuJH4tDd76WFswu/aF?= =?us-ascii?Q?E8yKmQRp+S+9cUHJpBFsw7Ov4VtXVZvAJfhb8G4IzG3hNztdeE18ZNIP+7ki?= =?us-ascii?Q?FajAy5+6NT7igeEwjyNFncGY/WhIOyeMIYznfD3A4NIF1WCKmv7IjatJXJEX?= =?us-ascii?Q?Bv/hbhNvmp8LZbPFtWb9wXdjWSOuohzNTqWzd+eEFIKfy/DnjWb/MDEgt5JO?= =?us-ascii?Q?CXLoc/ZYqm2oZbQDvbzVIr3fc5sIfBqgXXexp7286y0vFcEkGrkHJ3gg5BRh?= =?us-ascii?Q?VfmRfFiAG8ru7z3LeYsBtaX4oMEfZUoppPN4Rz6xbBEVNG1uuMSXo+NUaTjC?= =?us-ascii?Q?NGjwKJjMQoRuF99sM/mF6TLeS4J6Yw04O7hKKoJeRPCQvlPHln5KokHIlwUG?= =?us-ascii?Q?uSRnO6F1FkGkwRvdwmgP9OXwaTWaOTDRf5nBgs1DF+hoR7Vn6wW4RZ4Cxubp?= =?us-ascii?Q?Mq+Cua5I5IXaoxTJQCMA37oM4eES4mNlBtjc8/h3gMjT7IdyUe0VC6Duuc5L?= =?us-ascii?Q?qSUWRRIaMqfrqzZAxMtrOukuV+dAlJ4Bo5+56da6eTwDhrc254DdzxZSLeGl?= =?us-ascii?Q?ljStafeYjmahlF9VmahLhexJT/d5Lpp+1v7uVbpGLuXD/wEuVAvJkCxBVpx3?= =?us-ascii?Q?L7e5ZQ0QuQJEvIl6tVLhF6Iqt+vdyTDwt3E/OJMLKPNBLEfMlJq7oT0bZ5Uz?= =?us-ascii?Q?t6au8HHXbUIibN0Etmg9Y5upSCVKplICLW6ceXBE7L7997n9zsW4KYH3rgc0?= =?us-ascii?Q?UDL/J9xhvlP50VbTjBg9js835SO/N+n7MsuKP/hU6QacZL9T3ZcmBznqnKq5?= =?us-ascii?Q?D1rkUEEW9GO6Bvfrbkvc1p/NWdzh1eYyvEitJPdhLannMSK0yi6DSEInSQP5?= =?us-ascii?Q?h0vxoxsyvdC08cZkg1Y4POGN9F7Q5xW1zfa0Na+2Ex/Ux5g5xa2pSJnnfJny?= =?us-ascii?Q?Rj5SROYOkNYuFCsdVWaZi0TxxO7ErotzohjnxU7c94/fMVVH87CpjbU3/HvS?= =?us-ascii?Q?z+DzHj7vkhw3dHiapmHKvq716YmSdym81u93bAEQl/mpSPkDarw4Hhf642LK?= =?us-ascii?Q?TOqzsCb7GiqrW8tD66RyXpLEfPGJmOWo6hXYxTmO+V8PjEYCTQ2JlcrFLrqD?= =?us-ascii?Q?iPxi9U6uFtWGksDgvLpZD4Syx/L7b+D2lCBSAcFI?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 74b87056-eaae-4aad-104c-08db74050758 X-MS-Exchange-CrossTenant-AuthSource: LV2PR12MB5869.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 23 Jun 2023 16:15:15.1299 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: 5etcg6e6dK9zBPJg4LwANdRNShG4/iQSTNji5RkzHMndZaeNG6VQDDHKrdZQ3acS X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM4PR12MB5263 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Fri, Jun 02, 2023 at 05:16:47AM -0700, Yi Liu wrote: > This adds ioctl for userspace to bind device cdev fd to iommufd. > > 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. > > Tested-by: Yanting Jiang > Tested-by: Shameer Kolothum > Tested-by: Terrence Xu > Signed-off-by: Yi Liu > --- > drivers/vfio/device_cdev.c | 123 +++++++++++++++++++++++++++++++++++++ > drivers/vfio/vfio.h | 13 ++++ > drivers/vfio/vfio_main.c | 5 ++ > include/linux/vfio.h | 3 +- > include/uapi/linux/vfio.h | 27 ++++++++ > 5 files changed, 170 insertions(+), 1 deletion(-) > > diff --git a/drivers/vfio/device_cdev.c b/drivers/vfio/device_cdev.c > index 1c640016a824..a4498ddbe774 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" > > @@ -44,6 +45,128 @@ int vfio_device_fops_cdev_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) > + _vfio_device_get_kvm_safe(df->device, df->kvm); > + spin_unlock(&df->kvm_ref_lock); > +} I'm surprised symbol_get() can be called from a spinlock, but it sure looks like it can.. Also moving the if kvm is null test into _vfio_device_get_kvm_safe() will save a few lines. Also shouldn't be called _vfio_device... > +void vfio_df_cdev_close(struct vfio_device_file *df) > +{ > + struct vfio_device *device = df->device; > + > + /* > + * In the time of close, there is no contention with another one > + * changing this flag. So read df->access_granted without lock > + * and no smp_load_acquire() is ok. > + */ > + if (!df->access_granted) > + return; > + > + mutex_lock(&device->dev_set->lock); > + vfio_df_close(df); > + vfio_device_put_kvm(device); > + iommufd_ctx_put(df->iommufd); > + device->cdev_opened = false; > + mutex_unlock(&device->dev_set->lock); > + vfio_device_unblock_group(device); > +} Lets call this vfio_df_unbind_iommufd() and put it near vfio_df_ioctl_bind_iommufd() > static struct iommufd_ctx *vfio_get_iommufd_from_fd(int fd) This can probably be an iommufd function: iommufd_ctx_from_fd(int fd) > +long vfio_df_ioctl_bind_iommufd(struct vfio_device_file *df, > + struct vfio_device_bind_iommufd __user *arg) > +{ > + ret = copy_to_user(&arg->out_devid, &df->devid, > + sizeof(df->devid)) ? -EFAULT : 0; > + if (ret) > + goto out_close_device; > + > + /* > + * Paired with smp_load_acquire() in vfio_device_fops::ioctl/ > + * read/write/mmap > + */ > + smp_store_release(&df->access_granted, true); > + device->cdev_opened = true; Move the cdev_opened up above the release just for consistency. Jason