From patchwork Tue May 19 00:21:21 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: John Hubbard X-Patchwork-Id: 11556541 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 38386618 for ; Tue, 19 May 2020 00:21:33 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id EF39A20715 for ; Tue, 19 May 2020 00:21:32 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=nvidia.com header.i=@nvidia.com header.b="bSQ34rpR" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org EF39A20715 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=nvidia.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 13041900002; Mon, 18 May 2020 20:21:30 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id 0822B900003; Mon, 18 May 2020 20:21:30 -0400 (EDT) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id DF003900005; Mon, 18 May 2020 20:21:29 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0132.hostedemail.com [216.40.44.132]) by kanga.kvack.org (Postfix) with ESMTP id B50A3900003 for ; Mon, 18 May 2020 20:21:29 -0400 (EDT) Received: from smtpin06.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id 784CE8248076 for ; Tue, 19 May 2020 00:21:29 +0000 (UTC) X-FDA: 76831564698.06.body95_6443f9bab343b X-Spam-Summary: 1,0,0,,d41d8cd98f00b204,jhubbard@nvidia.com,,RULES_HIT:30003:30012:30034:30051:30054:30064:30070:30074,0,RBL:216.228.121.143:@nvidia.com:.lbl8.mailshell.net-62.18.0.100 64.10.201.10,CacheIP:none,Bayesian:0.5,0.5,0.5,Netcheck:none,DomainCache:0,MSF:not bulk,SPF:ft,MSBL:0,DNSBL:neutral,Custom_rules:0:0:0,LFtime:23,LUA_SUMMARY:none X-HE-Tag: body95_6443f9bab343b X-Filterd-Recvd-Size: 7475 Received: from hqnvemgate24.nvidia.com (hqnvemgate24.nvidia.com [216.228.121.143]) by imf13.hostedemail.com (Postfix) with ESMTP for ; Tue, 19 May 2020 00:21:28 +0000 (UTC) Received: from hqpgpgate101.nvidia.com (Not Verified[216.228.121.13]) by hqnvemgate24.nvidia.com (using TLS: TLSv1.2, DES-CBC3-SHA) id ; Mon, 18 May 2020 17:19:06 -0700 Received: from hqmail.nvidia.com ([172.20.161.6]) by hqpgpgate101.nvidia.com (PGP Universal service); Mon, 18 May 2020 17:21:27 -0700 X-PGP-Universal: processed; by hqpgpgate101.nvidia.com on Mon, 18 May 2020 17:21:27 -0700 Received: from HQMAIL101.nvidia.com (172.20.187.10) by HQMAIL111.nvidia.com (172.20.187.18) with Microsoft SMTP Server (TLS) id 15.0.1473.3; Tue, 19 May 2020 00:21:27 +0000 Received: from rnnvemgw01.nvidia.com (10.128.109.123) by HQMAIL101.nvidia.com (172.20.187.10) with Microsoft SMTP Server (TLS) id 15.0.1473.3 via Frontend Transport; Tue, 19 May 2020 00:21:27 +0000 Received: from sandstorm.nvidia.com (Not Verified[10.2.55.90]) by rnnvemgw01.nvidia.com with Trustwave SEG (v7,5,8,10121) id ; Mon, 18 May 2020 17:21:26 -0700 From: John Hubbard To: Andrew Morton CC: Souptick Joarder , Matthew Wilcox , Jani Nikula , "Joonas Lahtinen" , Rodrigo Vivi , David Airlie , Daniel Vetter , Chris Wilson , Tvrtko Ursulin , Matthew Auld , , , LKML , , John Hubbard Subject: [PATCH 1/4] mm/gup: move __get_user_pages_fast() down a few lines in gup.c Date: Mon, 18 May 2020 17:21:21 -0700 Message-ID: <20200519002124.2025955-2-jhubbard@nvidia.com> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200519002124.2025955-1-jhubbard@nvidia.com> References: <20200519002124.2025955-1-jhubbard@nvidia.com> MIME-Version: 1.0 X-NVConfidentiality: public DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nvidia.com; s=n1; t=1589847546; bh=rovyqRvoWmUY8LZ787X+YkZeUTez+YCYnMbA60VZKSY=; h=X-PGP-Universal:From:To:CC:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:MIME-Version:X-NVConfidentiality: Content-Transfer-Encoding:Content-Type; b=bSQ34rpRpEOByCzljfvC/zfc+UVQ2Rn8RyR8bdgPZR2DNTrpl8PkavKtjTEuscWrd JXJB008sQjaDiHiaipNpC7QRm3/xF0SR7xUuIz6f9FUne9lgD47lmRB40+OWyCy5gj mF7WTWbg/vfo7D17F9f2Roho+MrbfURPvNvvYVUNF6lX7Al0oraHZhMjiWHn6zqjaF ExjbImR95YFfmlP/Z8W7f1wb8ABXmC9OpXQZQ1kUxMifYC1qqdbjdcl7fq2CScM3uw X1hIFk76ZaYn5DST5AfgzCqeXzXV2vhyorhVCH1kG+7fccAblz6n8S/vtBqYbpRiGb 5JsazZgU3xcrw== 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: This is in order to avoid a forward declaration of internal_get_user_pages_fast(), in the next patch. This is code movement only--all generated code should be identical. Signed-off-by: John Hubbard --- mm/gup.c | 112 +++++++++++++++++++++++++++---------------------------- 1 file changed, 56 insertions(+), 56 deletions(-) diff --git a/mm/gup.c b/mm/gup.c index 50cd9323efff..4502846d57f9 100644 --- a/mm/gup.c +++ b/mm/gup.c @@ -2666,62 +2666,6 @@ static bool gup_fast_permitted(unsigned long start, unsigned long end) } #endif -/* - * Like get_user_pages_fast() except it's IRQ-safe in that it won't fall back to - * the regular GUP. - * Note a difference with get_user_pages_fast: this always returns the - * number of pages pinned, 0 if no pages were pinned. - * - * If the architecture does not support this function, simply return with no - * pages pinned. - */ -int __get_user_pages_fast(unsigned long start, int nr_pages, int write, - struct page **pages) -{ - unsigned long len, end; - unsigned long flags; - int nr_pinned = 0; - /* - * Internally (within mm/gup.c), gup fast variants must set FOLL_GET, - * because gup fast is always a "pin with a +1 page refcount" request. - */ - unsigned int gup_flags = FOLL_GET; - - if (write) - gup_flags |= FOLL_WRITE; - - start = untagged_addr(start) & PAGE_MASK; - len = (unsigned long) nr_pages << PAGE_SHIFT; - end = start + len; - - if (end <= start) - return 0; - if (unlikely(!access_ok((void __user *)start, len))) - return 0; - - /* - * Disable interrupts. We use the nested form as we can already have - * interrupts disabled by get_futex_key. - * - * With interrupts disabled, we block page table pages from being - * freed from under us. See struct mmu_table_batch comments in - * include/asm-generic/tlb.h for more details. - * - * We do not adopt an rcu_read_lock(.) here as we also want to - * block IPIs that come from THPs splitting. - */ - - if (IS_ENABLED(CONFIG_HAVE_FAST_GUP) && - gup_fast_permitted(start, end)) { - local_irq_save(flags); - gup_pgd_range(start, end, gup_flags, pages, &nr_pinned); - local_irq_restore(flags); - } - - return nr_pinned; -} -EXPORT_SYMBOL_GPL(__get_user_pages_fast); - static int __gup_longterm_unlocked(unsigned long start, int nr_pages, unsigned int gup_flags, struct page **pages) { @@ -2794,6 +2738,62 @@ static int internal_get_user_pages_fast(unsigned long start, int nr_pages, return ret; } +/* + * Like get_user_pages_fast() except it's IRQ-safe in that it won't fall back to + * the regular GUP. + * Note a difference with get_user_pages_fast: this always returns the + * number of pages pinned, 0 if no pages were pinned. + * + * If the architecture does not support this function, simply return with no + * pages pinned. + */ +int __get_user_pages_fast(unsigned long start, int nr_pages, int write, + struct page **pages) +{ + unsigned long len, end; + unsigned long flags; + int nr_pinned = 0; + /* + * Internally (within mm/gup.c), gup fast variants must set FOLL_GET, + * because gup fast is always a "pin with a +1 page refcount" request. + */ + unsigned int gup_flags = FOLL_GET; + + if (write) + gup_flags |= FOLL_WRITE; + + start = untagged_addr(start) & PAGE_MASK; + len = (unsigned long) nr_pages << PAGE_SHIFT; + end = start + len; + + if (end <= start) + return 0; + if (unlikely(!access_ok((void __user *)start, len))) + return 0; + + /* + * Disable interrupts. We use the nested form as we can already have + * interrupts disabled by get_futex_key. + * + * With interrupts disabled, we block page table pages from being + * freed from under us. See struct mmu_table_batch comments in + * include/asm-generic/tlb.h for more details. + * + * We do not adopt an rcu_read_lock(.) here as we also want to + * block IPIs that come from THPs splitting. + */ + + if (IS_ENABLED(CONFIG_HAVE_FAST_GUP) && + gup_fast_permitted(start, end)) { + local_irq_save(flags); + gup_pgd_range(start, end, gup_flags, pages, &nr_pinned); + local_irq_restore(flags); + } + + return nr_pinned; +} +EXPORT_SYMBOL_GPL(__get_user_pages_fast); + /** * get_user_pages_fast() - pin user pages in memory * @start: starting user address