From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id BEE3CC433DF for ; Tue, 2 Jun 2020 04:52:25 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 74DB62074B for ; Tue, 2 Jun 2020 04:52:25 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="y0ocCMkR" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 74DB62074B Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 19115280063; Tue, 2 Jun 2020 00:52:25 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 11B49280012; Tue, 2 Jun 2020 00:52:25 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id F2395280063; Tue, 2 Jun 2020 00:52:24 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0133.hostedemail.com [216.40.44.133]) by kanga.kvack.org (Postfix) with ESMTP id D547A280012 for ; Tue, 2 Jun 2020 00:52:24 -0400 (EDT) Received: from smtpin28.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id A596582499B9 for ; Tue, 2 Jun 2020 04:52:24 +0000 (UTC) X-FDA: 76883050608.28.lip17_4f2da07eefe3a Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin28.hostedemail.com (Postfix) with ESMTP id 78DEC6D7D for ; Tue, 2 Jun 2020 04:52:24 +0000 (UTC) X-HE-Tag: lip17_4f2da07eefe3a X-Filterd-Recvd-Size: 11221 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf12.hostedemail.com (Postfix) with ESMTP for ; Tue, 2 Jun 2020 04:52:23 +0000 (UTC) Received: from localhost.localdomain (c-73-231-172-41.hsd1.ca.comcast.net [73.231.172.41]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id A853C207FB; Tue, 2 Jun 2020 04:52:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1591073543; bh=35AcUUrbuWFpLjUrqMgI8tAc9TH96sfxWCLCB/n+3ZI=; h=Date:From:To:Subject:In-Reply-To:From; b=y0ocCMkREUsl2HE1f4PTRZiIu9I84o+x277DQ2Z/19hBQHhSz9AR0++Zl6yiNQ9Qh Yzeq2ECbiwGhHOrm+PaIPvntEV56QxxF3xMPpXbI/c3c2Bb84CLqXf26U5ixYa5Aos H9QMuoIwuqaTCl4rkD9cVGg2NjXSiGjSnmXMow/w= Date: Mon, 01 Jun 2020 21:52:22 -0700 From: Andrew Morton To: akpm@linux-foundation.org, arnd@arndb.de, dave.hansen@linux.intel.com, hch@lst.de, hpa@zytor.com, jroedel@suse.de, linux-mm@kvack.org, luto@kernel.org, mhocko@kernel.org, mingo@elte.hu, mm-commits@vger.kernel.org, peterz@infradead.org, rjw@rjwysocki.net, rostedt@goodmis.org, tglx@linutronix.de, torvalds@linux-foundation.org, vbabka@suse.cz, willy@infradead.org Subject: [patch 119/128] mm/vmalloc: track which page-table levels were modified Message-ID: <20200602045222.HAMCKSe8o%akpm@linux-foundation.org> In-Reply-To: <20200601214457.919c35648e96a2b46b573fe1@linux-foundation.org> User-Agent: s-nail v14.8.16 X-Rspamd-Queue-Id: 78DEC6D7D X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam01 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: From: Joerg Roedel Subject: mm/vmalloc: track which page-table levels were modified Track at which levels in the page-table entries were modified by vmap/vunmap. After the page-table has been modified, use that information do decide whether the new arch_sync_kernel_mappings() needs to be called. [akpm@linux-foundation.org: map_kernel_range_noflush() needs the arch_sync_kernel_mappings() call] Link: http://lkml.kernel.org/r/20200515140023.25469-3-joro@8bytes.org Signed-off-by: Joerg Roedel Acked-by: Andy Lutomirski Acked-by: Peter Zijlstra (Intel) Cc: Arnd Bergmann Cc: Christoph Hellwig Cc: Dave Hansen Cc: "H . Peter Anvin" Cc: Ingo Molnar Cc: Matthew Wilcox (Oracle) Cc: Michal Hocko Cc: "Rafael J. Wysocki" Cc: Steven Rostedt (VMware) Cc: Thomas Gleixner Cc: Vlastimil Babka Signed-off-by: Andrew Morton --- include/linux/vmalloc.h | 16 ++++++ mm/vmalloc.c | 95 +++++++++++++++++++++++++++----------- 2 files changed, 85 insertions(+), 26 deletions(-) --- a/include/linux/vmalloc.h~mm-vmalloc-track-which-page-table-levels-were-modified +++ a/include/linux/vmalloc.h @@ -134,6 +134,22 @@ void vmalloc_sync_mappings(void); void vmalloc_sync_unmappings(void); /* + * Architectures can set this mask to a combination of PGTBL_P?D_MODIFIED values + * and let generic vmalloc and ioremap code know when arch_sync_kernel_mappings() + * needs to be called. + */ +#ifndef ARCH_PAGE_TABLE_SYNC_MASK +#define ARCH_PAGE_TABLE_SYNC_MASK 0 +#endif + +/* + * There is no default implementation for arch_sync_kernel_mappings(). It is + * relied upon the compiler to optimize calls out if ARCH_PAGE_TABLE_SYNC_MASK + * is 0. + */ +void arch_sync_kernel_mappings(unsigned long start, unsigned long end); + +/* * Lowlevel-APIs (not for driver use!) */ --- a/mm/vmalloc.c~mm-vmalloc-track-which-page-table-levels-were-modified +++ a/mm/vmalloc.c @@ -69,7 +69,8 @@ static void free_work(struct work_struct /*** Page table manipulation functions ***/ -static void vunmap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end) +static void vunmap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, + pgtbl_mod_mask *mask) { pte_t *pte; @@ -78,59 +79,81 @@ static void vunmap_pte_range(pmd_t *pmd, pte_t ptent = ptep_get_and_clear(&init_mm, addr, pte); WARN_ON(!pte_none(ptent) && !pte_present(ptent)); } while (pte++, addr += PAGE_SIZE, addr != end); + *mask |= PGTBL_PTE_MODIFIED; } -static void vunmap_pmd_range(pud_t *pud, unsigned long addr, unsigned long end) +static void vunmap_pmd_range(pud_t *pud, unsigned long addr, unsigned long end, + pgtbl_mod_mask *mask) { pmd_t *pmd; unsigned long next; + int cleared; pmd = pmd_offset(pud, addr); do { next = pmd_addr_end(addr, end); - if (pmd_clear_huge(pmd)) + + cleared = pmd_clear_huge(pmd); + if (cleared || pmd_bad(*pmd)) + *mask |= PGTBL_PMD_MODIFIED; + + if (cleared) continue; if (pmd_none_or_clear_bad(pmd)) continue; - vunmap_pte_range(pmd, addr, next); + vunmap_pte_range(pmd, addr, next, mask); } while (pmd++, addr = next, addr != end); } -static void vunmap_pud_range(p4d_t *p4d, unsigned long addr, unsigned long end) +static void vunmap_pud_range(p4d_t *p4d, unsigned long addr, unsigned long end, + pgtbl_mod_mask *mask) { pud_t *pud; unsigned long next; + int cleared; pud = pud_offset(p4d, addr); do { next = pud_addr_end(addr, end); - if (pud_clear_huge(pud)) + + cleared = pud_clear_huge(pud); + if (cleared || pud_bad(*pud)) + *mask |= PGTBL_PUD_MODIFIED; + + if (cleared) continue; if (pud_none_or_clear_bad(pud)) continue; - vunmap_pmd_range(pud, addr, next); + vunmap_pmd_range(pud, addr, next, mask); } while (pud++, addr = next, addr != end); } -static void vunmap_p4d_range(pgd_t *pgd, unsigned long addr, unsigned long end) +static void vunmap_p4d_range(pgd_t *pgd, unsigned long addr, unsigned long end, + pgtbl_mod_mask *mask) { p4d_t *p4d; unsigned long next; + int cleared; p4d = p4d_offset(pgd, addr); do { next = p4d_addr_end(addr, end); - if (p4d_clear_huge(p4d)) + + cleared = p4d_clear_huge(p4d); + if (cleared || p4d_bad(*p4d)) + *mask |= PGTBL_P4D_MODIFIED; + + if (cleared) continue; if (p4d_none_or_clear_bad(p4d)) continue; - vunmap_pud_range(p4d, addr, next); + vunmap_pud_range(p4d, addr, next, mask); } while (p4d++, addr = next, addr != end); } /** * unmap_kernel_range_noflush - unmap kernel VM area - * @addr: start of the VM area to unmap + * @start: start of the VM area to unmap * @size: size of the VM area to unmap * * Unmap PFN_UP(@size) pages at @addr. The VM area @addr and @size specify @@ -141,24 +164,33 @@ static void vunmap_p4d_range(pgd_t *pgd, * for calling flush_cache_vunmap() on to-be-mapped areas before calling this * function and flush_tlb_kernel_range() after. */ -void unmap_kernel_range_noflush(unsigned long addr, unsigned long size) +void unmap_kernel_range_noflush(unsigned long start, unsigned long size) { - unsigned long end = addr + size; + unsigned long end = start + size; unsigned long next; pgd_t *pgd; + unsigned long addr = start; + pgtbl_mod_mask mask = 0; BUG_ON(addr >= end); + start = addr; pgd = pgd_offset_k(addr); do { next = pgd_addr_end(addr, end); + if (pgd_bad(*pgd)) + mask |= PGTBL_PGD_MODIFIED; if (pgd_none_or_clear_bad(pgd)) continue; - vunmap_p4d_range(pgd, addr, next); + vunmap_p4d_range(pgd, addr, next, &mask); } while (pgd++, addr = next, addr != end); + + if (mask & ARCH_PAGE_TABLE_SYNC_MASK) + arch_sync_kernel_mappings(start, end); } static int vmap_pte_range(pmd_t *pmd, unsigned long addr, - unsigned long end, pgprot_t prot, struct page **pages, int *nr) + unsigned long end, pgprot_t prot, struct page **pages, int *nr, + pgtbl_mod_mask *mask) { pte_t *pte; @@ -167,7 +199,7 @@ static int vmap_pte_range(pmd_t *pmd, un * callers keep track of where we're up to. */ - pte = pte_alloc_kernel(pmd, addr); + pte = pte_alloc_kernel_track(pmd, addr, mask); if (!pte) return -ENOMEM; do { @@ -180,55 +212,59 @@ static int vmap_pte_range(pmd_t *pmd, un set_pte_at(&init_mm, addr, pte, mk_pte(page, prot)); (*nr)++; } while (pte++, addr += PAGE_SIZE, addr != end); + *mask |= PGTBL_PTE_MODIFIED; return 0; } static int vmap_pmd_range(pud_t *pud, unsigned long addr, - unsigned long end, pgprot_t prot, struct page **pages, int *nr) + unsigned long end, pgprot_t prot, struct page **pages, int *nr, + pgtbl_mod_mask *mask) { pmd_t *pmd; unsigned long next; - pmd = pmd_alloc(&init_mm, pud, addr); + pmd = pmd_alloc_track(&init_mm, pud, addr, mask); if (!pmd) return -ENOMEM; do { next = pmd_addr_end(addr, end); - if (vmap_pte_range(pmd, addr, next, prot, pages, nr)) + if (vmap_pte_range(pmd, addr, next, prot, pages, nr, mask)) return -ENOMEM; } while (pmd++, addr = next, addr != end); return 0; } static int vmap_pud_range(p4d_t *p4d, unsigned long addr, - unsigned long end, pgprot_t prot, struct page **pages, int *nr) + unsigned long end, pgprot_t prot, struct page **pages, int *nr, + pgtbl_mod_mask *mask) { pud_t *pud; unsigned long next; - pud = pud_alloc(&init_mm, p4d, addr); + pud = pud_alloc_track(&init_mm, p4d, addr, mask); if (!pud) return -ENOMEM; do { next = pud_addr_end(addr, end); - if (vmap_pmd_range(pud, addr, next, prot, pages, nr)) + if (vmap_pmd_range(pud, addr, next, prot, pages, nr, mask)) return -ENOMEM; } while (pud++, addr = next, addr != end); return 0; } static int vmap_p4d_range(pgd_t *pgd, unsigned long addr, - unsigned long end, pgprot_t prot, struct page **pages, int *nr) + unsigned long end, pgprot_t prot, struct page **pages, int *nr, + pgtbl_mod_mask *mask) { p4d_t *p4d; unsigned long next; - p4d = p4d_alloc(&init_mm, pgd, addr); + p4d = p4d_alloc_track(&init_mm, pgd, addr, mask); if (!p4d) return -ENOMEM; do { next = p4d_addr_end(addr, end); - if (vmap_pud_range(p4d, addr, next, prot, pages, nr)) + if (vmap_pud_range(p4d, addr, next, prot, pages, nr, mask)) return -ENOMEM; } while (p4d++, addr = next, addr != end); return 0; @@ -255,21 +291,28 @@ static int vmap_p4d_range(pgd_t *pgd, un int map_kernel_range_noflush(unsigned long addr, unsigned long size, pgprot_t prot, struct page **pages) { + unsigned long start = addr; unsigned long end = addr + size; unsigned long next; pgd_t *pgd; int err = 0; int nr = 0; + pgtbl_mod_mask mask = 0; BUG_ON(addr >= end); pgd = pgd_offset_k(addr); do { next = pgd_addr_end(addr, end); - err = vmap_p4d_range(pgd, addr, next, prot, pages, &nr); + if (pgd_bad(*pgd)) + mask |= PGTBL_PGD_MODIFIED; + err = vmap_p4d_range(pgd, addr, next, prot, pages, &nr, &mask); if (err) return err; } while (pgd++, addr = next, addr != end); + if (mask & ARCH_PAGE_TABLE_SYNC_MASK) + arch_sync_kernel_mappings(start, end); + return 0; } _