From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f198.google.com (mail-pf0-f198.google.com [209.85.192.198]) by kanga.kvack.org (Postfix) with ESMTP id 336936B0006 for ; Wed, 20 Jun 2018 18:09:33 -0400 (EDT) Received: by mail-pf0-f198.google.com with SMTP id g20-v6so462814pfi.2 for ; Wed, 20 Jun 2018 15:09:33 -0700 (PDT) Received: from mga01.intel.com (mga01.intel.com. [192.55.52.88]) by mx.google.com with ESMTPS id r10-v6si3395620pfe.121.2018.06.20.15.09.31 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 20 Jun 2018 15:09:31 -0700 (PDT) From: Rick Edgecombe Subject: [PATCH 1/3] vmalloc: Add __vmalloc_node_try_addr function Date: Wed, 20 Jun 2018 15:09:28 -0700 Message-Id: <1529532570-21765-2-git-send-email-rick.p.edgecombe@intel.com> In-Reply-To: <1529532570-21765-1-git-send-email-rick.p.edgecombe@intel.com> References: <1529532570-21765-1-git-send-email-rick.p.edgecombe@intel.com> Sender: owner-linux-mm@kvack.org List-ID: To: tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com, x86@kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, kernel-hardening@lists.openwall.com Cc: kristen.c.accardi@intel.com, dave.hansen@intel.com, arjan.van.de.ven@intel.com, Rick Edgecombe Create __vmalloc_node_try_addr function that tries to allocate at a specific address. The implementation relies on __vmalloc_node_range for the bulk of the work. To keep this function from spamming the logs when an allocation failure is fails, __vmalloc_node_range is changed to only warn when __GFP_NOWARN is not set. This behavior is consistent with this flags interpretation in alloc_vmap_area. Signed-off-by: Rick Edgecombe --- include/linux/vmalloc.h | 3 +++ mm/vmalloc.c | 41 +++++++++++++++++++++++++++++++++++++++-- 2 files changed, 42 insertions(+), 2 deletions(-) diff --git a/include/linux/vmalloc.h b/include/linux/vmalloc.h index 398e9c9..6eaa896 100644 --- a/include/linux/vmalloc.h +++ b/include/linux/vmalloc.h @@ -82,6 +82,9 @@ extern void *__vmalloc_node_range(unsigned long size, unsigned long align, unsigned long start, unsigned long end, gfp_t gfp_mask, pgprot_t prot, unsigned long vm_flags, int node, const void *caller); +extern void *__vmalloc_node_try_addr(unsigned long addr, unsigned long size, + gfp_t gfp_mask, pgprot_t prot, unsigned long vm_flags, + int node, const void *caller); #ifndef CONFIG_MMU extern void *__vmalloc_node_flags(unsigned long size, int node, gfp_t flags); static inline void *__vmalloc_node_flags_caller(unsigned long size, int node, diff --git a/mm/vmalloc.c b/mm/vmalloc.c index cfea25b..9e0820c9 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -1710,6 +1710,42 @@ static void *__vmalloc_area_node(struct vm_struct *area, gfp_t gfp_mask, } /** + * __vmalloc_try_addr - try to alloc at a specific address + * @addr: address to try + * @size: size to try + * @gfp_mask: flags for the page level allocator + * @prot: protection mask for the allocated pages + * @vm_flags: additional vm area flags (e.g. %VM_NO_GUARD) + * @node: node to use for allocation or NUMA_NO_NODE + * @caller: caller's return address + * + * Try to allocate at the specific address. If it succeeds the address is + * returned. If it fails NULL is returned. It may trigger TLB flushes. + */ +void *__vmalloc_node_try_addr(unsigned long addr, unsigned long size, + gfp_t gfp_mask, pgprot_t prot, unsigned long vm_flags, + int node, const void *caller) +{ + unsigned long addr_end; + unsigned long vsize = PAGE_ALIGN(size); + + if (!vsize || (vsize >> PAGE_SHIFT) > totalram_pages) + return NULL; + + if (!(vm_flags & VM_NO_GUARD)) + vsize += PAGE_SIZE; + + addr_end = addr + vsize; + + if (addr > addr_end) + return NULL; + + return __vmalloc_node_range(size, 1, addr, addr_end, + gfp_mask | __GFP_NOWARN, prot, vm_flags, node, + caller); +} + +/** * __vmalloc_node_range - allocate virtually contiguous memory * @size: allocation size * @align: desired alignment @@ -1759,8 +1795,9 @@ void *__vmalloc_node_range(unsigned long size, unsigned long align, return addr; fail: - warn_alloc(gfp_mask, NULL, - "vmalloc: allocation failure: %lu bytes", real_size); + if (!(gfp_mask & __GFP_NOWARN)) + warn_alloc(gfp_mask, NULL, + "vmalloc: allocation failure: %lu bytes", real_size); return NULL; } -- 2.7.4