From patchwork Mon Aug 21 12:30:49 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kefeng Wang X-Patchwork-Id: 1823626 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=lists.ozlabs.org (client-ip=2404:9400:2:0:216:3eff:fee1:b9f1; helo=lists.ozlabs.org; envelope-from=linuxppc-dev-bounces+incoming=patchwork.ozlabs.org@lists.ozlabs.org; receiver=patchwork.ozlabs.org) Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2404:9400:2:0:216:3eff:fee1:b9f1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (secp384r1)) (No client certificate requested) by legolas.ozlabs.org (Postfix) with ESMTPS id 4RTss95Prsz1ybW for ; Mon, 21 Aug 2023 22:55:25 +1000 (AEST) Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4RTss91ZJMz3bwL for ; Mon, 21 Aug 2023 22:55:25 +1000 (AEST) X-Original-To: linuxppc-dev@lists.ozlabs.org Delivered-To: linuxppc-dev@lists.ozlabs.org Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=huawei.com (client-ip=45.249.212.187; helo=szxga01-in.huawei.com; envelope-from=wangkefeng.wang@huawei.com; receiver=lists.ozlabs.org) Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4RTsrw64SPz30hn for ; Mon, 21 Aug 2023 22:55:12 +1000 (AEST) Received: from dggpemm100001.china.huawei.com (unknown [172.30.72.56]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4RTsF23D6sztShV; Mon, 21 Aug 2023 20:27:34 +0800 (CST) Received: from localhost.localdomain (10.175.112.125) by dggpemm100001.china.huawei.com (7.185.36.93) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.31; Mon, 21 Aug 2023 20:31:15 +0800 From: Kefeng Wang To: Andrew Morton , Subject: [PATCH rfc v2 03/10] x86: mm: use try_vma_locked_page_fault() Date: Mon, 21 Aug 2023 20:30:49 +0800 Message-ID: <20230821123056.2109942-4-wangkefeng.wang@huawei.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20230821123056.2109942-1-wangkefeng.wang@huawei.com> References: <20230821123056.2109942-1-wangkefeng.wang@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.175.112.125] X-ClientProxiedBy: dggems705-chm.china.huawei.com (10.3.19.182) To dggpemm100001.china.huawei.com (7.185.36.93) X-CFilter-Loop: Reflected 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: Kefeng Wang , x86@kernel.org, loongarch@lists.linux.dev, Peter Zijlstra , Catalin Marinas , Dave Hansen , "H . Peter Anvin" , WANG Xuerui , Will Deacon , Alexander Gordeev , linux-s390@vger.kernel.org, Huacai Chen , Russell King , willy@infradead.org, Ingo Molnar , Gerald Schaefer , Christian Borntraeger , Albert Ou , Vasily Gorbik , Heiko Carstens , Nicholas Piggin , Borislav Petkov , Andy Lutomirski , Paul Walmsley , Thomas Gleixner , surenb@google.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-ri scv@lists.infradead.org, Palmer Dabbelt , Sven Schnelle , linuxppc-dev@lists.ozlabs.org Errors-To: linuxppc-dev-bounces+incoming=patchwork.ozlabs.org@lists.ozlabs.org Sender: "Linuxppc-dev" Use new try_vma_locked_page_fault() helper to simplify code. No functional change intended. Signed-off-by: Kefeng Wang --- arch/x86/mm/fault.c | 55 +++++++++++++++++++-------------------------- 1 file changed, 23 insertions(+), 32 deletions(-) diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index ab778eac1952..3edc9edc0b28 100644 --- a/arch/x86/mm/fault.c +++ b/arch/x86/mm/fault.c @@ -1227,6 +1227,13 @@ do_kern_addr_fault(struct pt_regs *regs, unsigned long hw_error_code, } NOKPROBE_SYMBOL(do_kern_addr_fault); +#ifdef CONFIG_PER_VMA_LOCK +bool arch_vma_access_error(struct vm_area_struct *vma, struct vm_fault *vmf) +{ + return access_error(vmf->fault_code, vma); +} +#endif + /* * Handle faults in the user portion of the address space. Nothing in here * should check X86_PF_USER without a specific justification: for almost @@ -1241,13 +1248,13 @@ void do_user_addr_fault(struct pt_regs *regs, unsigned long address) { struct vm_area_struct *vma; - struct task_struct *tsk; - struct mm_struct *mm; + struct mm_struct *mm = current->mm; vm_fault_t fault; - unsigned int flags = FAULT_FLAG_DEFAULT; - - tsk = current; - mm = tsk->mm; + struct vm_fault vmf = { + .real_address = address, + .fault_code = error_code, + .flags = FAULT_FLAG_DEFAULT + }; if (unlikely((error_code & (X86_PF_USER | X86_PF_INSTR)) == X86_PF_INSTR)) { /* @@ -1311,7 +1318,7 @@ void do_user_addr_fault(struct pt_regs *regs, */ if (user_mode(regs)) { local_irq_enable(); - flags |= FAULT_FLAG_USER; + vmf.flags |= FAULT_FLAG_USER; } else { if (regs->flags & X86_EFLAGS_IF) local_irq_enable(); @@ -1326,11 +1333,11 @@ void do_user_addr_fault(struct pt_regs *regs, * maybe_mkwrite() can create a proper shadow stack PTE. */ if (error_code & X86_PF_SHSTK) - flags |= FAULT_FLAG_WRITE; + vmf.flags |= FAULT_FLAG_WRITE; if (error_code & X86_PF_WRITE) - flags |= FAULT_FLAG_WRITE; + vmf.flags |= FAULT_FLAG_WRITE; if (error_code & X86_PF_INSTR) - flags |= FAULT_FLAG_INSTRUCTION; + vmf.flags |= FAULT_FLAG_INSTRUCTION; #ifdef CONFIG_X86_64 /* @@ -1350,26 +1357,11 @@ void do_user_addr_fault(struct pt_regs *regs, } #endif - if (!(flags & FAULT_FLAG_USER)) - goto lock_mmap; - - vma = lock_vma_under_rcu(mm, address); - if (!vma) - goto lock_mmap; - - if (unlikely(access_error(error_code, vma))) { - vma_end_read(vma); - goto lock_mmap; - } - fault = handle_mm_fault(vma, address, flags | FAULT_FLAG_VMA_LOCK, regs); - if (!(fault & (VM_FAULT_RETRY | VM_FAULT_COMPLETED))) - vma_end_read(vma); - - if (!(fault & VM_FAULT_RETRY)) { - count_vm_vma_lock_event(VMA_LOCK_SUCCESS); + fault = try_vma_locked_page_fault(&vmf); + if (fault == VM_FAULT_NONE) + goto retry; + if (!(fault & VM_FAULT_RETRY)) goto done; - } - count_vm_vma_lock_event(VMA_LOCK_RETRY); /* Quick path to respond to signals */ if (fault_signal_pending(fault, regs)) { @@ -1379,7 +1371,6 @@ void do_user_addr_fault(struct pt_regs *regs, ARCH_DEFAULT_PKEY); return; } -lock_mmap: retry: vma = lock_mm_and_find_vma(mm, address, regs); @@ -1410,7 +1401,7 @@ void do_user_addr_fault(struct pt_regs *regs, * userland). The return to userland is identified whenever * FAULT_FLAG_USER|FAULT_FLAG_KILLABLE are both set in flags. */ - fault = handle_mm_fault(vma, address, flags, regs); + fault = handle_mm_fault(vma, address, vmf.flags, regs); if (fault_signal_pending(fault, regs)) { /* @@ -1434,7 +1425,7 @@ void do_user_addr_fault(struct pt_regs *regs, * that we made any progress. Handle this case first. */ if (unlikely(fault & VM_FAULT_RETRY)) { - flags |= FAULT_FLAG_TRIED; + vmf.flags |= FAULT_FLAG_TRIED; goto retry; }