Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752083AbaFFQjm (ORCPT ); Fri, 6 Jun 2014 12:39:42 -0400 Received: from mail-pd0-f174.google.com ([209.85.192.174]:64180 "EHLO mail-pd0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751624AbaFFQjk (ORCPT ); Fri, 6 Jun 2014 12:39:40 -0400 MIME-Version: 1.0 X-Originating-IP: [2a01:e35:2434:4600:61b0:c77e:e905:5cc9] In-Reply-To: <1402002841.9207.260.camel@ul30vt.home> References: <1401987808-23596-1-git-send-email-a.motakis@virtualopensystems.com> <1401987808-23596-11-git-send-email-a.motakis@virtualopensystems.com> <1402002841.9207.260.camel@ul30vt.home> From: Antonios Motakis Date: Fri, 6 Jun 2014 18:39:19 +0200 Message-ID: Subject: Re: [RFC PATCH v6 10/20] vfio/platform: return info for device and its memory mapped IO regions To: Alex Williamson Cc: kvm-arm , Linux IOMMU , VirtualOpenSystems Technical Team , alvise rigo , KVM devel mailing list , Christoffer Dall , Will Deacon , Kim Phillips , Stuart Yoder , Eric Auger , Catalin Marinas , Mark Rutland , Vladimir Murzin , open list Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jun 5, 2014 at 11:14 PM, Alex Williamson wrote: > On Thu, 2014-06-05 at 19:03 +0200, Antonios Motakis wrote: >> A VFIO userspace driver will start by opening the VFIO device >> that corresponds to an IOMMU group, and will use the ioctl interface >> to get the basic device info, such as number of memory regions and >> interrupts, and their properties. >> >> This patch enables the IOCTLs: >> - VFIO_DEVICE_GET_INFO >> - VFIO_DEVICE_GET_REGION_INFO >> >> IRQ info is provided by one of the latter patches. >> >> Signed-off-by: Antonios Motakis >> --- >> drivers/vfio/platform/vfio_platform.c | 79 +++++++++++++++++++++++++-- >> drivers/vfio/platform/vfio_platform_private.h | 17 ++++++ >> 2 files changed, 90 insertions(+), 6 deletions(-) >> >> diff --git a/drivers/vfio/platform/vfio_platform.c b/drivers/vfio/platform/vfio_platform.c >> index 1df76d8..eeaebc4 100644 >> --- a/drivers/vfio/platform/vfio_platform.c >> +++ b/drivers/vfio/platform/vfio_platform.c >> @@ -34,17 +34,66 @@ >> #define DRIVER_AUTHOR "Antonios Motakis " >> #define DRIVER_DESC "VFIO for platform devices - User Level meta-driver" >> >> +static int vfio_platform_regions_init(struct vfio_platform_device *vdev) >> +{ >> + int cnt = 0, i; >> + >> + while (platform_get_resource(vdev->pdev, IORESOURCE_MEM, cnt)) >> + cnt++; >> + >> + vdev->region = kzalloc(sizeof(struct vfio_platform_region) * cnt, >> + GFP_KERNEL); >> + if (!vdev->region) >> + return -ENOMEM; >> + >> + for (i = 0; i < cnt; i++) { >> + struct resource *res = >> + platform_get_resource(vdev->pdev, IORESOURCE_MEM, i); >> + >> + if (!res) >> + goto err; >> + >> + vdev->region[i].addr = res->start; >> + vdev->region[i].size = resource_size(res); >> + vdev->region[i].flags = 0; >> + } >> + >> + vdev->num_regions = cnt; >> + >> + return 0; >> +err: >> + kfree(vdev->region); >> + return -EINVAL; >> +} >> + >> +static void vfio_platform_regions_cleanup(struct vfio_platform_device *vdev) >> +{ >> + vdev->num_regions = 0; >> + kfree(vdev->region); >> +} >> + >> static void vfio_platform_release(void *device_data) >> { >> + struct vfio_platform_device *vdev = device_data; >> + >> + vfio_platform_regions_cleanup(vdev); >> + >> module_put(THIS_MODULE); >> } >> >> static int vfio_platform_open(void *device_data) >> { >> + struct vfio_platform_device *vdev = device_data; >> + int ret; >> + >> if (!try_module_get(THIS_MODULE)) >> return -ENODEV; >> >> - return 0; >> + ret = vfio_platform_regions_init(vdev); >> + if (ret) >> + module_put(THIS_MODULE); >> + >> + return ret; > > The user can call VFIO_GROUP_GET_DEVICE_FD for a single device more than > once, vfio_pci maintains a reference count to make sure we only allocate > and initialize on the first open and cleanup on the last close. > Ack >> } >> >> static long vfio_platform_ioctl(void *device_data, >> @@ -65,18 +114,36 @@ static long vfio_platform_ioctl(void *device_data, >> return -EINVAL; >> >> info.flags = VFIO_DEVICE_FLAGS_PLATFORM; >> - info.num_regions = 0; >> + info.num_regions = vdev->num_regions; >> info.num_irqs = 0; >> >> return copy_to_user((void __user *)arg, &info, minsz); >> >> - } else if (cmd == VFIO_DEVICE_GET_REGION_INFO) >> - return -EINVAL; >> + } else if (cmd == VFIO_DEVICE_GET_REGION_INFO) { >> + struct vfio_region_info info; >> + >> + minsz = offsetofend(struct vfio_region_info, offset); >> + >> + if (copy_from_user(&info, (void __user *)arg, minsz)) >> + return -EFAULT; >> + >> + if (info.argsz < minsz) >> + return -EINVAL; >> + >> + if (info.index >= vdev->num_regions) >> + return -EINVAL; >> + >> + /* map offset to the physical address */ >> + info.offset = VFIO_PLATFORM_INDEX_TO_OFFSET(info.index); >> + info.size = vdev->region[info.index].size; >> + info.flags = vdev->region[info.index].flags; >> + >> + return copy_to_user((void __user *)arg, &info, minsz); >> >> - else if (cmd == VFIO_DEVICE_GET_IRQ_INFO) >> + } else if (cmd == VFIO_DEVICE_GET_IRQ_INFO) { >> return -EINVAL; >> >> - else if (cmd == VFIO_DEVICE_SET_IRQS) >> + } else if (cmd == VFIO_DEVICE_SET_IRQS) >> return -EINVAL; >> >> else if (cmd == VFIO_DEVICE_RESET) >> diff --git a/drivers/vfio/platform/vfio_platform_private.h b/drivers/vfio/platform/vfio_platform_private.h >> index 4ae88f8..3448f918 100644 >> --- a/drivers/vfio/platform/vfio_platform_private.h >> +++ b/drivers/vfio/platform/vfio_platform_private.h >> @@ -15,8 +15,25 @@ >> #ifndef VFIO_PLATFORM_PRIVATE_H >> #define VFIO_PLATFORM_PRIVATE_H >> >> +#define VFIO_PLATFORM_OFFSET_SHIFT 40 >> +#define VFIO_PLATFORM_OFFSET_MASK (((u64)(1) << VFIO_PLATFORM_OFFSET_SHIFT) - 1) >> + >> +#define VFIO_PLATFORM_OFFSET_TO_INDEX(off) \ >> + (off >> VFIO_PLATFORM_OFFSET_SHIFT) >> + >> +#define VFIO_PLATFORM_INDEX_TO_OFFSET(index) \ >> + ((u64)(index) << VFIO_PLATFORM_OFFSET_SHIFT) >> + >> +struct vfio_platform_region { >> + u64 addr; >> + resource_size_t size; >> + u32 flags; >> +}; >> + >> struct vfio_platform_device { >> struct platform_device *pdev; >> + struct vfio_platform_region *region; > > "regions" (plural) has slightly better consistency. Thanks, > Ack as well. -- Antonios Motakis Virtual Open Systems -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/