From ae94da898133947c2d1f005da10838478e4548db Mon Sep 17 00:00:00 2001 From: Mike Kravetz Date: Wed, 3 Jun 2020 16:00:34 -0700 Subject: hugetlbfs: add arch_hugetlb_valid_size Patch series "Clean up hugetlb boot command line processing", v4. Longpeng(Mike) reported a weird message from hugetlb command line processing and proposed a solution [1]. While the proposed patch does address the specific issue, there are other related issues in command line processing. As hugetlbfs evolved, updates to command line processing have been made to meet immediate needs and not necessarily in a coordinated manner. The result is that some processing is done in arch specific code, some is done in arch independent code and coordination is problematic. Semantics can vary between architectures. The patch series does the following: - Define arch specific arch_hugetlb_valid_size routine used to validate passed huge page sizes. - Move hugepagesz= command line parsing out of arch specific code and into an arch independent routine. - Clean up command line processing to follow desired semantics and document those semantics. [1] https://lore.kernel.org/linux-mm/20200305033014.1152-1-longpeng2@huawei.com This patch (of 3): The architecture independent routine hugetlb_default_setup sets up the default huge pages size. It has no way to verify if the passed value is valid, so it accepts it and attempts to validate at a later time. This requires undocumented cooperation between the arch specific and arch independent code. For architectures that support more than one huge page size, provide a routine arch_hugetlb_valid_size to validate a huge page size. hugetlb_default_setup can use this to validate passed values. arch_hugetlb_valid_size will also be used in a subsequent patch to move processing of the "hugepagesz=" in arch specific code to a common routine in arch independent code. Signed-off-by: Mike Kravetz Signed-off-by: Andrew Morton Acked-by: Gerald Schaefer [s390] Acked-by: Will Deacon Cc: Catalin Marinas Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: Paul Walmsley Cc: Palmer Dabbelt Cc: Albert Ou Cc: Heiko Carstens Cc: Vasily Gorbik Cc: Christian Borntraeger Cc: David S. Miller Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Dave Hansen Cc: Jonathan Corbet Cc: Longpeng Cc: Christophe Leroy Cc: Randy Dunlap Cc: Mina Almasry Cc: Peter Xu Cc: Nitesh Narayan Lal Cc: Anders Roxell Cc: "Aneesh Kumar K.V" Cc: Qian Cai Cc: Stephen Rothwell Link: http://lkml.kernel.org/r/20200428205614.246260-1-mike.kravetz@oracle.com Link: http://lkml.kernel.org/r/20200428205614.246260-2-mike.kravetz@oracle.com Link: http://lkml.kernel.org/r/20200417185049.275845-1-mike.kravetz@oracle.com Link: http://lkml.kernel.org/r/20200417185049.275845-2-mike.kravetz@oracle.com Signed-off-by: Linus Torvalds --- arch/s390/mm/hugetlbpage.c | 16 ++++++++++++---- 1 file changed, 12 insertions(+), 4 deletions(-) (limited to 'arch/s390') diff --git a/arch/s390/mm/hugetlbpage.c b/arch/s390/mm/hugetlbpage.c index 4632d4e26b66..2f2b6b5b3d29 100644 --- a/arch/s390/mm/hugetlbpage.c +++ b/arch/s390/mm/hugetlbpage.c @@ -254,16 +254,24 @@ follow_huge_pud(struct mm_struct *mm, unsigned long address, return pud_page(*pud) + ((address & ~PUD_MASK) >> PAGE_SHIFT); } +bool __init arch_hugetlb_valid_size(unsigned long size) +{ + if (MACHINE_HAS_EDAT1 && size == PMD_SIZE) + return true; + else if (MACHINE_HAS_EDAT2 && size == PUD_SIZE) + return true; + else + return false; +} + static __init int setup_hugepagesz(char *opt) { unsigned long size; char *string = opt; size = memparse(opt, &opt); - if (MACHINE_HAS_EDAT1 && size == PMD_SIZE) { - hugetlb_add_hstate(PMD_SHIFT - PAGE_SHIFT); - } else if (MACHINE_HAS_EDAT2 && size == PUD_SIZE) { - hugetlb_add_hstate(PUD_SHIFT - PAGE_SHIFT); + if (arch_hugetlb_valid_size(size)) { + hugetlb_add_hstate(ilog2(size) - PAGE_SHIFT); } else { hugetlb_bad_size(); pr_err("hugepagesz= specifies an unsupported page size %s\n", -- cgit v1.2.3