From patchwork Tue Jun 11 14:40:48 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 1114064 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 45NZh651K2z9sBp for ; Wed, 12 Jun 2019 02:09:26 +1000 (AEST) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=infradead.org header.i=@infradead.org header.b="Qsrqx7Gj"; dkim-atps=neutral Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 45NZh63vySzDqdh for ; Wed, 12 Jun 2019 02:09:26 +1000 (AEST) X-Original-To: linuxppc-dev@lists.ozlabs.org Delivered-To: linuxppc-dev@lists.ozlabs.org Authentication-Results: lists.ozlabs.org; spf=none (mailfrom) smtp.mailfrom=bombadil.srs.infradead.org (client-ip=2607:7c80:54:e::133; helo=bombadil.infradead.org; envelope-from=batv+98d4ae9035936dc2f97b+5770+infradead.org+hch@bombadil.srs.infradead.org; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=infradead.org header.i=@infradead.org header.b="Qsrqx7Gj"; dkim-atps=neutral Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:e::133]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 45NXkt1LDkzDqVL for ; Wed, 12 Jun 2019 00:41:40 +1000 (AEST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender :Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From :Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help: List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=gzNr8cC+RcaEr7a/7B73Y02JTGGTEGr38/f2ngv8wBc=; b=Qsrqx7Gjl2GC8vf87J1kV0OBS9 Tt5zTsC9u5FMT4aBrJhjCtE6a9K5hEj6huEHcTGHIZTp0lPnrD3O3q6Taf6l5zAkrj04NvtpjMFZz QSbVSiRFTFj1K1DWEpoIo8npKLbZp/icZRb4FmghwPVhUl2hQQ3GZ8V/iVwFa0djVedxsNvetvYQ/ U8rrAK2RSgtkuzMw1qKgToiMIX3BNteGcXa0JARj45dk/04PT26mlULgR6rFGQSTQUrd9alXQpxPZ v2Ok1HiUy9mTgFSunZi7dGsxAIdFawyIN5trdPG1sAjbfv2nBSw2rK5taBkGiygEsnDU61sdcdRaz phR5Tu6w==; Received: from mpp-cp1-natpool-1-037.ethz.ch ([82.130.71.37] helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.92 #3 (Red Hat Linux)) id 1hahxZ-0005O7-RH; Tue, 11 Jun 2019 14:41:14 +0000 From: Christoph Hellwig To: Linus Torvalds , Paul Burton , James Hogan , Yoshinori Sato , Rich Felker , "David S. Miller" Subject: [PATCH 02/16] mm: simplify gup_fast_permitted Date: Tue, 11 Jun 2019 16:40:48 +0200 Message-Id: <20190611144102.8848-3-hch@lst.de> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190611144102.8848-1-hch@lst.de> References: <20190611144102.8848-1-hch@lst.de> MIME-Version: 1.0 X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-sh@vger.kernel.org, Andrey Konovalov , x86@kernel.org, linux-mips@vger.kernel.org, Nicholas Piggin , linux-kernel@vger.kernel.org, linux-mm@kvack.org, Khalid Aziz , Paul Mackerras , sparclinux@vger.kernel.org, linuxppc-dev@lists.ozlabs.org Errors-To: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org Sender: "Linuxppc-dev" Pass in the already calculated end value instead of recomputing it, and leave the end > start check in the callers instead of duplicating them in the arch code. Signed-off-by: Christoph Hellwig Reviewed-by: Jason Gunthorpe --- arch/s390/include/asm/pgtable.h | 8 +------- arch/x86/include/asm/pgtable_64.h | 8 +------- mm/gup.c | 17 +++++++---------- 3 files changed, 9 insertions(+), 24 deletions(-) diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h index 9f0195d5fa16..9b274fcaacb6 100644 --- a/arch/s390/include/asm/pgtable.h +++ b/arch/s390/include/asm/pgtable.h @@ -1270,14 +1270,8 @@ static inline pte_t *pte_offset(pmd_t *pmd, unsigned long address) #define pte_offset_map(pmd, address) pte_offset_kernel(pmd, address) #define pte_unmap(pte) do { } while (0) -static inline bool gup_fast_permitted(unsigned long start, int nr_pages) +static inline bool gup_fast_permitted(unsigned long start, unsigned long end) { - unsigned long len, end; - - len = (unsigned long) nr_pages << PAGE_SHIFT; - end = start + len; - if (end < start) - return false; return end <= current->mm->context.asce_limit; } #define gup_fast_permitted gup_fast_permitted diff --git a/arch/x86/include/asm/pgtable_64.h b/arch/x86/include/asm/pgtable_64.h index 0bb566315621..4990d26dfc73 100644 --- a/arch/x86/include/asm/pgtable_64.h +++ b/arch/x86/include/asm/pgtable_64.h @@ -259,14 +259,8 @@ extern void init_extra_mapping_uc(unsigned long phys, unsigned long size); extern void init_extra_mapping_wb(unsigned long phys, unsigned long size); #define gup_fast_permitted gup_fast_permitted -static inline bool gup_fast_permitted(unsigned long start, int nr_pages) +static inline bool gup_fast_permitted(unsigned long start, unsigned long end) { - unsigned long len, end; - - len = (unsigned long)nr_pages << PAGE_SHIFT; - end = start + len; - if (end < start) - return false; if (end >> __VIRTUAL_MASK_SHIFT) return false; return true; diff --git a/mm/gup.c b/mm/gup.c index 6bb521db67ec..3237f33792e6 100644 --- a/mm/gup.c +++ b/mm/gup.c @@ -2123,13 +2123,9 @@ static void gup_pgd_range(unsigned long addr, unsigned long end, * Check if it's allowed to use __get_user_pages_fast() for the range, or * we need to fall back to the slow version: */ -bool gup_fast_permitted(unsigned long start, int nr_pages) +static bool gup_fast_permitted(unsigned long start, unsigned long end) { - unsigned long len, end; - - len = (unsigned long) nr_pages << PAGE_SHIFT; - end = start + len; - return end >= start; + return true; } #endif @@ -2150,6 +2146,8 @@ int __get_user_pages_fast(unsigned long start, int nr_pages, int write, 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; @@ -2165,7 +2163,7 @@ int __get_user_pages_fast(unsigned long start, int nr_pages, int write, * block IPIs that come from THPs splitting. */ - if (gup_fast_permitted(start, nr_pages)) { + if (gup_fast_permitted(start, end)) { local_irq_save(flags); gup_pgd_range(start, end, write ? FOLL_WRITE : 0, pages, &nr); local_irq_restore(flags); @@ -2224,13 +2222,12 @@ int get_user_pages_fast(unsigned long start, int nr_pages, len = (unsigned long) nr_pages << PAGE_SHIFT; end = start + len; - if (nr_pages <= 0) + if (end <= start) return 0; - if (unlikely(!access_ok((void __user *)start, len))) return -EFAULT; - if (gup_fast_permitted(start, nr_pages)) { + if (gup_fast_permitted(start, end)) { local_irq_disable(); gup_pgd_range(addr, end, gup_flags, pages, &nr); local_irq_enable();