Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752576AbbDBCa4 (ORCPT ); Wed, 1 Apr 2015 22:30:56 -0400 Received: from mail-pa0-f45.google.com ([209.85.220.45]:33208 "EHLO mail-pa0-f45.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751521AbbDBCay (ORCPT ); Wed, 1 Apr 2015 22:30:54 -0400 Message-ID: <551CA9D7.2060804@ozlabs.ru> Date: Thu, 02 Apr 2015 13:30:47 +1100 From: Alexey Kardashevskiy User-Agent: Mozilla/5.0 (X11; Linux i686 on x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.5.0 MIME-Version: 1.0 To: Alex Williamson CC: linuxppc-dev@lists.ozlabs.org, Benjamin Herrenschmidt , Paul Mackerras , linux-kernel@vger.kernel.org Subject: Re: [PATCH kernel v7 04/31] vfio: powerpc/spapr: Use it_page_size References: <1427468115-2224-1-git-send-email-aik@ozlabs.ru> <1427468115-2224-5-git-send-email-aik@ozlabs.ru> <1427924904.5567.303.camel@redhat.com> In-Reply-To: <1427924904.5567.303.camel@redhat.com> Content-Type: text/plain; charset=koi8-r; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2463 Lines: 68 On 04/02/2015 08:48 AM, Alex Williamson wrote: > On Sat, 2015-03-28 at 01:54 +1100, Alexey Kardashevskiy wrote: >> This makes use of the it_page_size from the iommu_table struct >> as page size can differ. >> >> This replaces missing IOMMU_PAGE_SHIFT macro in commented debug code >> as recently introduced IOMMU_PAGE_XXX macros do not include >> IOMMU_PAGE_SHIFT. >> >> Signed-off-by: Alexey Kardashevskiy >> Reviewed-by: David Gibson >> --- >> drivers/vfio/vfio_iommu_spapr_tce.c | 26 +++++++++++++------------- >> 1 file changed, 13 insertions(+), 13 deletions(-) >> >> diff --git a/drivers/vfio/vfio_iommu_spapr_tce.c b/drivers/vfio/vfio_iommu_spapr_tce.c >> index f835e63..8bbee22 100644 >> --- a/drivers/vfio/vfio_iommu_spapr_tce.c >> +++ b/drivers/vfio/vfio_iommu_spapr_tce.c >> @@ -91,7 +91,7 @@ static int tce_iommu_enable(struct tce_container *container) >> * enforcing the limit based on the max that the guest can map. >> */ >> down_write(¤t->mm->mmap_sem); >> - npages = (tbl->it_size << IOMMU_PAGE_SHIFT_4K) >> PAGE_SHIFT; >> + npages = (tbl->it_size << tbl->it_page_shift) >> PAGE_SHIFT; >> locked = current->mm->locked_vm + npages; >> lock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; >> if (locked > lock_limit && !capable(CAP_IPC_LOCK)) { >> @@ -120,7 +120,7 @@ static void tce_iommu_disable(struct tce_container *container) >> >> down_write(¤t->mm->mmap_sem); >> current->mm->locked_vm -= (container->tbl->it_size << >> - IOMMU_PAGE_SHIFT_4K) >> PAGE_SHIFT; >> + container->tbl->it_page_shift) >> PAGE_SHIFT; >> up_write(¤t->mm->mmap_sem); >> } >> >> @@ -222,7 +222,7 @@ static long tce_iommu_build(struct tce_container *container, >> tce, ret); >> break; >> } >> - tce += IOMMU_PAGE_SIZE_4K; >> + tce += IOMMU_PAGE_SIZE(tbl); > > > Is PAGE_SIZE ever smaller than IOMMU_PAGE_SIZE(tbl)? IOW, can the page > we got from get_user_pages_fast() ever not completely fill the tce > entry? Yes. IOMMU_PAGE_SIZE is 4K/64K/16M (16M is with huge pages enabled in QEMU with -mempath), PAGE_SIZE is 4K/64K (normally 64K). > (Have I asked this before? Sorry if so) :) -- Alexey -- 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/