From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752490AbeBSKFz convert rfc822-to-8bit (ORCPT ); Mon, 19 Feb 2018 05:05:55 -0500 Received: from lhrrgout.huawei.com ([194.213.3.17]:26627 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752370AbeBSKFw (ORCPT ); Mon, 19 Feb 2018 05:05:52 -0500 From: Shameerali Kolothum Thodi To: Alex Williamson CC: "eric.auger@redhat.com" , "pmorel@linux.vnet.ibm.com" , "kvm@vger.kernel.org" , "linux-kernel@vger.kernel.org" , Linuxarm , John Garry , "xuwei (O)" Subject: RE: [PATCH v3 5/6] vfio/type1: Add IOVA range capability support Thread-Topic: [PATCH v3 5/6] vfio/type1: Add IOVA range capability support Thread-Index: AQHTpkH2bkEz1obYekandfuFFj5ANaOniSiAgAP7prA= Date: Mon, 19 Feb 2018 10:05:40 +0000 Message-ID: <5FC3163CFD30C246ABAA99954A238FA838648B26@FRAEML521-MBX.china.huawei.com> References: <20180215094504.4972-1-shameerali.kolothum.thodi@huawei.com> <20180215094504.4972-6-shameerali.kolothum.thodi@huawei.com> <20180216151223.381bfcf9@w520.home> In-Reply-To: <20180216151223.381bfcf9@w520.home> Accept-Language: en-GB, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.202.227.237] Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 8BIT MIME-Version: 1.0 X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > -----Original Message----- > From: Alex Williamson [mailto:alex.williamson@redhat.com] > Sent: Friday, February 16, 2018 10:12 PM > To: Shameerali Kolothum Thodi > Cc: eric.auger@redhat.com; pmorel@linux.vnet.ibm.com; > kvm@vger.kernel.org; linux-kernel@vger.kernel.org; Linuxarm > ; John Garry ; xuwei (O) > > Subject: Re: [PATCH v3 5/6] vfio/type1: Add IOVA range capability support > > On Thu, 15 Feb 2018 09:45:03 +0000 > Shameer Kolothum wrote: > > > This allows the user-space to retrieve the supported IOVA > > range(s), excluding any reserved regions. The implementation > > is based on capability chains, added to VFIO_IOMMU_GET_INFO ioctl. > > > > Signed-off-by: Shameer Kolothum > > --- > > drivers/vfio/vfio_iommu_type1.c | 92 > +++++++++++++++++++++++++++++++++++++++++ > > include/uapi/linux/vfio.h | 23 +++++++++++ > > 2 files changed, 115 insertions(+) > > > > diff --git a/drivers/vfio/vfio_iommu_type1.c > b/drivers/vfio/vfio_iommu_type1.c > > index dae01c5..21e575c 100644 > > --- a/drivers/vfio/vfio_iommu_type1.c > > +++ b/drivers/vfio/vfio_iommu_type1.c > > @@ -1925,6 +1925,68 @@ static int > vfio_domains_have_iommu_cache(struct vfio_iommu *iommu) > > return ret; > > } > > > > +static int vfio_add_iova_cap(struct vfio_info_cap *caps, > > + struct vfio_iommu_type1_info_cap_iova_range *cap_iovas, > > + size_t size) > > +{ > > + struct vfio_info_cap_header *header; > > + struct vfio_iommu_type1_info_cap_iova_range *iova_cap; > > + > > + header = vfio_info_cap_add(caps, size, > > + > VFIO_IOMMU_TYPE1_INFO_CAP_IOVA_RANGE, 1); > > + if (IS_ERR(header)) > > + return PTR_ERR(header); > > + > > + iova_cap = container_of(header, > > + struct vfio_iommu_type1_info_cap_iova_range, > header); > > + iova_cap->nr_iovas = cap_iovas->nr_iovas; > > + memcpy(iova_cap->iova_ranges, cap_iovas->iova_ranges, > > + cap_iovas->nr_iovas * sizeof(*cap_iovas->iova_ranges)); > > + return 0; > > +} > > + > > +static int vfio_build_iommu_iova_caps(struct vfio_iommu *iommu, > > + struct vfio_info_cap *caps) > > +{ > > + struct vfio_iommu_type1_info_cap_iova_range *cap_iovas; > > + struct vfio_iova *iova; > > + size_t size; > > + int iovas = 0, i = 0, ret; > > + > > + mutex_lock(&iommu->lock); > > + > > + list_for_each_entry(iova, &iommu->iova_list, list) > > + iovas++; > > + > > + if (!iovas) { > > + ret = -EINVAL; > > + goto out_unlock; > > + } > > + > > + size = sizeof(*cap_iovas) + (iovas * sizeof(*cap_iovas->iova_ranges)); > > + > > + cap_iovas = kzalloc(size, GFP_KERNEL); > > + if (!cap_iovas) { > > + ret = -ENOMEM; > > + goto out_unlock; > > + } > > + > > + cap_iovas->nr_iovas = iovas; > > + > > + list_for_each_entry(iova, &iommu->iova_list, list) { > > + cap_iovas->iova_ranges[i].start = iova->start; > > + cap_iovas->iova_ranges[i].end = iova->end; > > + i++; > > + } > > + > > + ret = vfio_add_iova_cap(caps, cap_iovas, size); > > + > > + kfree(cap_iovas); > > +out_unlock: > > + mutex_unlock(&iommu->lock); > > + return ret; > > +} > > + > > static long vfio_iommu_type1_ioctl(void *iommu_data, > > unsigned int cmd, unsigned long arg) > > { > > @@ -1946,6 +2008,8 @@ static long vfio_iommu_type1_ioctl(void > *iommu_data, > > } > > } else if (cmd == VFIO_IOMMU_GET_INFO) { > > struct vfio_iommu_type1_info info; > > + struct vfio_info_cap caps = { .buf = NULL, .size = 0 }; > > + int ret; > > > > minsz = offsetofend(struct vfio_iommu_type1_info, > iova_pgsizes); > > > > @@ -1959,6 +2023,34 @@ static long vfio_iommu_type1_ioctl(void > *iommu_data, > > > > info.iova_pgsizes = vfio_pgsize_bitmap(iommu); > > > > + if (info.argsz == minsz) > > + goto done; > > I don't think the above branch should exist, we want to tell the user > via argsz and flags that capabilities exist even if they only passed > the previous structure size through. Ok. I will remove this. > > + > > + ret = vfio_build_iommu_iova_caps(iommu, &caps); > > + if (ret) > > + return ret; > > + > > + if (caps.size) { > > + info.flags |= VFIO_IOMMU_INFO_CAPS; > > + minsz = offsetofend(struct vfio_iommu_type1_info, > > + cap_offset); > > Only update minsz if this is within the provided argsz. Ok. > > + if (info.argsz < sizeof(info) + caps.size) { > > + info.argsz = sizeof(info) + caps.size; > > + info.cap_offset = 0; > > IOW, if cap_offset doesn't get copied to the user, that's ok, we've > provided them the flag and argsz they need to recognize it's there and > call with a sufficient buffer next time. Ok. I will change the logic here. Thanks, Shameer > > + } else { > > + vfio_info_cap_shift(&caps, sizeof(info)); > > + if (copy_to_user((void __user *)arg + > > + sizeof(info), caps.buf, > > + caps.size)) { > > + kfree(caps.buf); > > + return -EFAULT; > > + } > > + info.cap_offset = sizeof(info); > > + } > > + > > + kfree(caps.buf); > > + } > > +done: > > return copy_to_user((void __user *)arg, &info, minsz) ? > > -EFAULT : 0; > > > > diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h > > index c743721..46b49e9 100644 > > --- a/include/uapi/linux/vfio.h > > +++ b/include/uapi/linux/vfio.h > > @@ -589,7 +589,30 @@ struct vfio_iommu_type1_info { > > __u32 argsz; > > __u32 flags; > > #define VFIO_IOMMU_INFO_PGSIZES (1 << 0) /* supported page sizes info */ > > +#define VFIO_IOMMU_INFO_CAPS (1 << 1) /* Info supports caps */ > > __u64 iova_pgsizes; /* Bitmap of supported page sizes */ > > + __u32 cap_offset; /* Offset within info struct of first cap */ > > +}; > > + > > +/* > > + * The IOVA capability allows to report the valid IOVA range(s) > > + * excluding any reserved regions associated with dev group. Any dma > > + * map attempt outside the valid iova range will return error. > > + * > > + * The structures below define version 1 of this capability. > > + */ > > +#define VFIO_IOMMU_TYPE1_INFO_CAP_IOVA_RANGE 1 > > + > > +struct vfio_iova_range { > > + __u64 start; > > + __u64 end; > > +}; > > + > > +struct vfio_iommu_type1_info_cap_iova_range { > > + struct vfio_info_cap_header header; > > + __u32 nr_iovas; > > + __u32 reserved; > > + struct vfio_iova_range iova_ranges[]; > > }; > > > > #define VFIO_IOMMU_GET_INFO _IO(VFIO_TYPE, VFIO_BASE + 12)