From patchwork Wed May 8 14:43:25 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "kirill.shutemov@linux.intel.com" X-Patchwork-Id: 10936037 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 7BBEE924 for ; Wed, 8 May 2019 14:52:16 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 6CA872880C for ; Wed, 8 May 2019 14:52:16 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 6AA5A28A26; Wed, 8 May 2019 14:52:16 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 9ED392899D for ; Wed, 8 May 2019 14:52:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728695AbfEHOwJ (ORCPT ); Wed, 8 May 2019 10:52:09 -0400 Received: from mga01.intel.com ([192.55.52.88]:9094 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728088AbfEHOoj (ORCPT ); Wed, 8 May 2019 10:44:39 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga006.fm.intel.com ([10.253.24.20]) by fmsmga101.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 08 May 2019 07:44:38 -0700 X-ExtLoop1: 1 Received: from black.fi.intel.com ([10.237.72.28]) by fmsmga006.fm.intel.com with ESMTP; 08 May 2019 07:44:34 -0700 Received: by black.fi.intel.com (Postfix, from userid 1000) id CB0B2355; Wed, 8 May 2019 17:44:28 +0300 (EEST) From: "Kirill A. Shutemov" To: Andrew Morton , x86@kernel.org, Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , Borislav Petkov , Peter Zijlstra , Andy Lutomirski , David Howells Cc: Kees Cook , Dave Hansen , Kai Huang , Jacob Pan , Alison Schofield , linux-mm@kvack.org, kvm@vger.kernel.org, keyrings@vger.kernel.org, linux-kernel@vger.kernel.org, "Kirill A. Shutemov" Subject: [PATCH, RFC 05/62] mm/page_alloc: Handle allocation for encrypted memory Date: Wed, 8 May 2019 17:43:25 +0300 Message-Id: <20190508144422.13171-6-kirill.shutemov@linux.intel.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190508144422.13171-1-kirill.shutemov@linux.intel.com> References: <20190508144422.13171-1-kirill.shutemov@linux.intel.com> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP For encrypted memory, we need to allocate pages for a specific encryption KeyID. There are two cases when we need to allocate a page for encryption: - Allocation for an encrypted VMA; - Allocation for migration of encrypted page; The first case can be covered within alloc_page_vma(). We know KeyID from the VMA. The second case requires few new page allocation routines that would allocate the page for a specific KeyID. An encrypted page has to be cleared after KeyID set. This is handled in prep_encrypted_page() that will be provided by arch-specific code. Any custom allocator that dials with encrypted pages has to call prep_encrypted_page() too. See compaction_alloc() for instance. Signed-off-by: Kirill A. Shutemov --- include/linux/gfp.h | 45 ++++++++++++++++++++++++++++++++----- include/linux/migrate.h | 14 +++++++++--- mm/compaction.c | 3 +++ mm/mempolicy.c | 27 ++++++++++++++++------ mm/migrate.c | 4 ++-- mm/page_alloc.c | 50 +++++++++++++++++++++++++++++++++++++++++ 6 files changed, 126 insertions(+), 17 deletions(-) diff --git a/include/linux/gfp.h b/include/linux/gfp.h index b101aa294157..1716dbe587c9 100644 --- a/include/linux/gfp.h +++ b/include/linux/gfp.h @@ -463,16 +463,43 @@ static inline void arch_free_page(struct page *page, int order) { } static inline void arch_alloc_page(struct page *page, int order) { } #endif +#ifndef prep_encrypted_page +static inline void prep_encrypted_page(struct page *page, int order, + int keyid, bool zero) +{ +} +#endif + +/* + * Encrypted page has to be cleared once keyid is set, not on allocation. + */ +static inline bool deferred_page_zero(int keyid, gfp_t *gfp_mask) +{ + if (keyid && (*gfp_mask & __GFP_ZERO)) { + *gfp_mask &= ~__GFP_ZERO; + return true; + } + + return false; +} + struct page * __alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order, int preferred_nid, nodemask_t *nodemask); +struct page * +__alloc_pages_nodemask_keyid(gfp_t gfp_mask, unsigned int order, + int preferred_nid, nodemask_t *nodemask, int keyid); + static inline struct page * __alloc_pages(gfp_t gfp_mask, unsigned int order, int preferred_nid) { return __alloc_pages_nodemask(gfp_mask, order, preferred_nid, NULL); } +struct page *__alloc_pages_node_keyid(int nid, int keyid, + gfp_t gfp_mask, unsigned int order); + /* * Allocate pages, preferring the node given as nid. The node must be valid and * online. For more general interface, see alloc_pages_node(). @@ -500,6 +527,19 @@ static inline struct page *alloc_pages_node(int nid, gfp_t gfp_mask, return __alloc_pages_node(nid, gfp_mask, order); } +static inline struct page *alloc_pages_node_keyid(int nid, int keyid, + gfp_t gfp_mask, unsigned int order) +{ + if (nid == NUMA_NO_NODE) + nid = numa_mem_id(); + + return __alloc_pages_node_keyid(nid, keyid, gfp_mask, order); +} + +extern struct page *alloc_pages_vma(gfp_t gfp_mask, int order, + struct vm_area_struct *vma, unsigned long addr, + int node, bool hugepage); + #ifdef CONFIG_NUMA extern struct page *alloc_pages_current(gfp_t gfp_mask, unsigned order); @@ -508,14 +548,9 @@ alloc_pages(gfp_t gfp_mask, unsigned int order) { return alloc_pages_current(gfp_mask, order); } -extern struct page *alloc_pages_vma(gfp_t gfp_mask, int order, - struct vm_area_struct *vma, unsigned long addr, - int node, bool hugepage); #else #define alloc_pages(gfp_mask, order) \ alloc_pages_node(numa_node_id(), gfp_mask, order) -#define alloc_pages_vma(gfp_mask, order, vma, addr, node, false)\ - alloc_pages(gfp_mask, order) #endif #define alloc_page(gfp_mask) alloc_pages(gfp_mask, 0) #define alloc_page_vma(gfp_mask, vma, addr) \ diff --git a/include/linux/migrate.h b/include/linux/migrate.h index e13d9bf2f9a5..a6e068762d08 100644 --- a/include/linux/migrate.h +++ b/include/linux/migrate.h @@ -38,9 +38,16 @@ static inline struct page *new_page_nodemask(struct page *page, unsigned int order = 0; struct page *new_page = NULL; - if (PageHuge(page)) + if (PageHuge(page)) { + /* + * HugeTLB doesn't support encryption. We shouldn't see + * such pages. + */ + if (WARN_ON_ONCE(page_keyid(page))) + return NULL; return alloc_huge_page_nodemask(page_hstate(compound_head(page)), preferred_nid, nodemask); + } if (PageTransHuge(page)) { gfp_mask |= GFP_TRANSHUGE; @@ -50,8 +57,9 @@ static inline struct page *new_page_nodemask(struct page *page, if (PageHighMem(page) || (zone_idx(page_zone(page)) == ZONE_MOVABLE)) gfp_mask |= __GFP_HIGHMEM; - new_page = __alloc_pages_nodemask(gfp_mask, order, - preferred_nid, nodemask); + /* Allocate a page with the same KeyID as the source page */ + new_page = __alloc_pages_nodemask_keyid(gfp_mask, order, + preferred_nid, nodemask, page_keyid(page)); if (new_page && PageTransHuge(new_page)) prep_transhuge_page(new_page); diff --git a/mm/compaction.c b/mm/compaction.c index 3319e0872d01..559b8bd6d245 100644 --- a/mm/compaction.c +++ b/mm/compaction.c @@ -1557,6 +1557,9 @@ static struct page *compaction_alloc(struct page *migratepage, list_del(&freepage->lru); cc->nr_freepages--; + /* Prepare the page using the same KeyID as the source page */ + if (freepage) + prep_encrypted_page(freepage, 0, page_keyid(migratepage), false); return freepage; } diff --git a/mm/mempolicy.c b/mm/mempolicy.c index 14b18449c623..5cad39fb7b35 100644 --- a/mm/mempolicy.c +++ b/mm/mempolicy.c @@ -961,22 +961,29 @@ static void migrate_page_add(struct page *page, struct list_head *pagelist, /* page allocation callback for NUMA node migration */ struct page *alloc_new_node_page(struct page *page, unsigned long node) { - if (PageHuge(page)) + if (PageHuge(page)) { + /* + * HugeTLB doesn't support encryption. We shouldn't see + * such pages. + */ + if (WARN_ON_ONCE(page_keyid(page))) + return NULL; return alloc_huge_page_node(page_hstate(compound_head(page)), node); - else if (PageTransHuge(page)) { + } else if (PageTransHuge(page)) { struct page *thp; - thp = alloc_pages_node(node, + thp = alloc_pages_node_keyid(node, page_keyid(page), (GFP_TRANSHUGE | __GFP_THISNODE), HPAGE_PMD_ORDER); if (!thp) return NULL; prep_transhuge_page(thp); return thp; - } else - return __alloc_pages_node(node, GFP_HIGHUSER_MOVABLE | - __GFP_THISNODE, 0); + } else { + return __alloc_pages_node_keyid(node, page_keyid(page), + GFP_HIGHUSER_MOVABLE | __GFP_THISNODE, 0); + } } /* @@ -2053,9 +2060,13 @@ alloc_pages_vma(gfp_t gfp, int order, struct vm_area_struct *vma, { struct mempolicy *pol; struct page *page; - int preferred_nid; + bool deferred_zero; + int keyid, preferred_nid; nodemask_t *nmask; + keyid = vma_keyid(vma); + deferred_zero = deferred_page_zero(keyid, &gfp); + pol = get_vma_policy(vma, addr); if (pol->mode == MPOL_INTERLEAVE) { @@ -2097,6 +2108,8 @@ alloc_pages_vma(gfp_t gfp, int order, struct vm_area_struct *vma, page = __alloc_pages_nodemask(gfp, order, preferred_nid, nmask); mpol_cond_put(pol); out: + if (page) + prep_encrypted_page(page, order, keyid, deferred_zero); return page; } diff --git a/mm/migrate.c b/mm/migrate.c index 663a5449367a..04b36a56865d 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -1880,7 +1880,7 @@ static struct page *alloc_misplaced_dst_page(struct page *page, int nid = (int) data; struct page *newpage; - newpage = __alloc_pages_node(nid, + newpage = __alloc_pages_node_keyid(nid, page_keyid(page), (GFP_HIGHUSER_MOVABLE | __GFP_THISNODE | __GFP_NOMEMALLOC | __GFP_NORETRY | __GFP_NOWARN) & @@ -2006,7 +2006,7 @@ int migrate_misplaced_transhuge_page(struct mm_struct *mm, int page_lru = page_is_file_cache(page); unsigned long start = address & HPAGE_PMD_MASK; - new_page = alloc_pages_node(node, + new_page = alloc_pages_node_keyid(node, page_keyid(page), (GFP_TRANSHUGE_LIGHT | __GFP_THISNODE), HPAGE_PMD_ORDER); if (!new_page) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index c02cff1ed56e..ab1d8661aa87 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -3930,6 +3930,41 @@ should_compact_retry(struct alloc_context *ac, unsigned int order, int alloc_fla } #endif /* CONFIG_COMPACTION */ +#ifndef CONFIG_NUMA +struct page *alloc_pages_vma(gfp_t gfp_mask, int order, + struct vm_area_struct *vma, unsigned long addr, + int node, bool hugepage) +{ + struct page *page; + bool deferred_zero; + int keyid = vma_keyid(vma); + + deferred_zero = deferred_page_zero(keyid, &gfp_mask); + page = alloc_pages(gfp_mask, order); + if (page) + prep_encrypted_page(page, order, keyid, deferred_zero); + + return page; +} +#endif + +struct page * __alloc_pages_node_keyid(int nid, int keyid, + gfp_t gfp_mask, unsigned int order) +{ + struct page *page; + bool deferred_zero; + + VM_BUG_ON(nid < 0 || nid >= MAX_NUMNODES); + VM_WARN_ON(!node_online(nid)); + + deferred_zero = deferred_page_zero(keyid, &gfp_mask); + page = __alloc_pages(gfp_mask, order, nid); + if (page) + prep_encrypted_page(page, order, keyid, deferred_zero); + + return page; +} + #ifdef CONFIG_LOCKDEP static struct lockdep_map __fs_reclaim_map = STATIC_LOCKDEP_MAP_INIT("fs_reclaim", &__fs_reclaim_map); @@ -4645,6 +4680,21 @@ __alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order, int preferred_nid, } EXPORT_SYMBOL(__alloc_pages_nodemask); +struct page * +__alloc_pages_nodemask_keyid(gfp_t gfp_mask, unsigned int order, + int preferred_nid, nodemask_t *nodemask, int keyid) +{ + struct page *page; + bool deferred_zero; + + deferred_zero = deferred_page_zero(keyid, &gfp_mask); + page = __alloc_pages_nodemask(gfp_mask, order, preferred_nid, nodemask); + if (page) + prep_encrypted_page(page, order, keyid, deferred_zero); + return page; +} +EXPORT_SYMBOL(__alloc_pages_nodemask_keyid); + /* * Common helper functions. Never use with __GFP_HIGHMEM because the returned * address cannot represent highmem pages. Use alloc_pages and then kmap if