From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from foss.arm.com ([217.140.110.172]:59548 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726011AbhAMHDE (ORCPT ); Wed, 13 Jan 2021 02:03:04 -0500 Subject: Re: [PATCH V2 3/3] s390/mm: Define arch_get_mappable_range() References: <1608218912-28932-1-git-send-email-anshuman.khandual@arm.com> <1608218912-28932-4-git-send-email-anshuman.khandual@arm.com> <87ae0b7c-0e95-6068-900e-d813a53f2732@redhat.com> From: Anshuman Khandual Message-ID: <1efac09f-3eea-51fd-7754-98659a5e0054@arm.com> Date: Wed, 13 Jan 2021 12:32:34 +0530 MIME-Version: 1.0 In-Reply-To: <87ae0b7c-0e95-6068-900e-d813a53f2732@redhat.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit List-ID: To: David Hildenbrand , linux-mm@kvack.org, akpm@linux-foundation.org, hca@linux.ibm.com, catalin.marinas@arm.com Cc: linux-arm-kernel@lists.infradead.org, linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org, Vasily Gorbik , Will Deacon , Ard Biesheuvel , Mark Rutland On 1/11/21 4:10 PM, David Hildenbrand wrote: > On 17.12.20 16:28, Anshuman Khandual wrote: >> This overrides arch_get_mappabble_range() on s390 platform which will be >> used with recently added generic framework. It modifies the existing range >> check in vmem_add_mapping() using arch_get_mappable_range(). It also adds a >> VM_BUG_ON() check that would ensure that memhp_range_allowed() has already >> been called on the hotplug path. >> >> Cc: Heiko Carstens >> Cc: Vasily Gorbik >> Cc: David Hildenbrand >> Cc: linux-s390@vger.kernel.org >> Cc: linux-kernel@vger.kernel.org >> Acked-by: Heiko Carstens >> Signed-off-by: Anshuman Khandual >> --- >> arch/s390/mm/init.c | 1 + >> arch/s390/mm/vmem.c | 15 ++++++++++++++- >> 2 files changed, 15 insertions(+), 1 deletion(-) >> >> diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c >> index 77767850d0d0..e0e78234ae57 100644 >> --- a/arch/s390/mm/init.c >> +++ b/arch/s390/mm/init.c >> @@ -291,6 +291,7 @@ int arch_add_memory(int nid, u64 start, u64 size, >> if (WARN_ON_ONCE(params->pgprot.pgprot != PAGE_KERNEL.pgprot)) >> return -EINVAL; >> >> + VM_BUG_ON(!memhp_range_allowed(start, size, 1)); > > s/1/true/ Sure, will do. > >> rc = vmem_add_mapping(start, size); >> if (rc) >> return rc; >> diff --git a/arch/s390/mm/vmem.c b/arch/s390/mm/vmem.c >> index b239f2ba93b0..e10e563ad2b4 100644 >> --- a/arch/s390/mm/vmem.c >> +++ b/arch/s390/mm/vmem.c >> @@ -4,6 +4,7 @@ >> * Author(s): Heiko Carstens >> */ >> >> +#include >> #include >> #include >> #include >> @@ -532,11 +533,23 @@ void vmem_remove_mapping(unsigned long start, unsigned long size) >> mutex_unlock(&vmem_mutex); >> } >> >> +struct range arch_get_mappable_range(void) >> +{ >> + struct range memhp_range; >> + >> + memhp_range.start = 0; >> + memhp_range.end = VMEM_MAX_PHYS; > > s/ / / > > IIRC, the range is inclusive? "VMEM_MAX_PHYS - 1" then, and adjust the > check below. Right, the memory range is inclusive at both ends. Hence will update the code here. diff --git a/arch/s390/mm/vmem.c b/arch/s390/mm/vmem.c index 21cabe3473d7..afc39ff1cc8d 100644 --- a/arch/s390/mm/vmem.c +++ b/arch/s390/mm/vmem.c @@ -538,7 +538,7 @@ struct range arch_get_mappable_range(void) struct range memhp_range; memhp_range.start = 0; - memhp_range.end = VMEM_MAX_PHYS; + memhp_range.end = VMEM_MAX_PHYS - 1; return memhp_range; } @@ -549,7 +549,7 @@ int vmem_add_mapping(unsigned long start, unsigned long size) range = arch_get_mappable_range(); if (start < range.start || - start + size > range.end || + start + size > range.end + 1 || start + size < start) return -ERANGE; (start + size - 1) is valid only when it is upto the inclusive range.end value.