From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 5905C1A0BD9 for ; Tue, 3 Feb 2015 11:14:54 +1100 (AEDT) Message-ID: <1422922365.22865.448.camel@redhat.com> Subject: Re: [PATCH v3 08/24] powerpc/spapr: vfio: Switch from iommu_table to new powerpc_iommu From: Alex Williamson To: Alexey Kardashevskiy Date: Mon, 02 Feb 2015 17:12:45 -0700 In-Reply-To: <1422523325-1389-9-git-send-email-aik@ozlabs.ru> References: <1422523325-1389-1-git-send-email-aik@ozlabs.ru> <1422523325-1389-9-git-send-email-aik@ozlabs.ru> Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Cc: Alexander Graf , Gavin Shan , Alexander Gordeev , Paul Mackerras , linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Thu, 2015-01-29 at 20:21 +1100, Alexey Kardashevskiy wrote: > Modern IBM POWERPC systems support multiple (currently two) TCE tables > per IOMMU group (a.k.a. PE). This adds a powerpc_iommu container > for TCE tables. Right now just one table is supported. > > Signed-off-by: Alexey Kardashevskiy > --- > arch/powerpc/include/asm/iommu.h | 18 ++-- > arch/powerpc/kernel/eeh.c | 2 +- > arch/powerpc/kernel/iommu.c | 34 ++++---- > arch/powerpc/platforms/powernv/pci-ioda.c | 37 +++++--- > arch/powerpc/platforms/powernv/pci-p5ioc2.c | 16 ++-- > arch/powerpc/platforms/powernv/pci.c | 2 +- > arch/powerpc/platforms/powernv/pci.h | 4 +- > arch/powerpc/platforms/pseries/iommu.c | 9 +- > drivers/vfio/vfio_iommu_spapr_tce.c | 131 ++++++++++++++++++++-------- > 9 files changed, 170 insertions(+), 83 deletions(-) [snip] > diff --git a/drivers/vfio/vfio_iommu_spapr_tce.c b/drivers/vfio/vfio_iommu_spapr_tce.c > index 29d5708..28909e1 100644 > --- a/drivers/vfio/vfio_iommu_spapr_tce.c > +++ b/drivers/vfio/vfio_iommu_spapr_tce.c > @@ -84,7 +84,7 @@ static void decrement_locked_vm(long npages) > */ > struct tce_container { > struct mutex lock; > - struct iommu_table *tbl; > + struct iommu_group *grp; > bool enabled; > }; > > @@ -104,16 +104,40 @@ static bool tce_check_page_size(struct page *page, unsigned page_shift) > return false; > } > > +static struct iommu_table *spapr_tce_find_table( > + struct tce_container *container, > + phys_addr_t ioba) > +{ > + long i; > + struct iommu_table *ret = NULL; > + struct powerpc_iommu *iommu = iommu_group_get_iommudata(container->grp); > + > + mutex_lock(&container->lock); > + for (i = 0; i < POWERPC_IOMMU_MAX_TABLES; ++i) { > + struct iommu_table *tbl = &iommu->tables[i]; > + unsigned long entry = ioba >> tbl->it_page_shift; > + unsigned long start = tbl->it_offset; > + unsigned long end = start + tbl->it_size; > + > + if ((start <= entry) && (entry < end)) { > + ret = tbl; > + break; > + } > + } > + mutex_unlock(&container->lock); > + > + return ret; > +} > + > static int tce_iommu_enable(struct tce_container *container) > { > int ret = 0; > + struct powerpc_iommu *iommu; > + struct iommu_table *tbl; > > - if (!container->tbl) > + if (!container->grp) > return -ENXIO; > > - if (!current->mm) > - return -ESRCH; /* process exited */ > - > if (container->enabled) > return -EBUSY; > > @@ -142,7 +166,12 @@ static int tce_iommu_enable(struct tce_container *container) > * as this information is only available from KVM and VFIO is > * KVM agnostic. > */ > - ret = try_increment_locked_vm(IOMMU_TABLE_PAGES(container->tbl)); > + iommu = iommu_group_get_iommudata(container->grp); > + if (!iommu) > + return -EFAULT; > + > + tbl = &iommu->tables[0]; There should probably be a comment somewhere documenting that tables[0] is the small window and presumably [1] will be the DDW.