From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755659AbcC2A3a (ORCPT ); Mon, 28 Mar 2016 20:29:30 -0400 Received: from mga09.intel.com ([134.134.136.24]:5821 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753255AbcC2A3Z (ORCPT ); Mon, 28 Mar 2016 20:29:25 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.24,408,1455004800"; d="scan'208";a="677092770" Subject: [PATCH v3] x86, pmem: use memcpy_mcsafe() for memcpy_from_pmem() From: Dan Williams To: linux-nvdimm@ml01.01.org Cc: Ingo Molnar , Tony Luck , Thomas Gleixner , Peter Zijlstra , linux-kernel@vger.kernel.org, Andy Lutomirski , Borislav Petkov , Andrew Morton , Linus Torvalds , Ross Zwisler Date: Mon, 28 Mar 2016 17:28:45 -0700 Message-ID: <20160329002845.10978.8879.stgit@dwillia2-desk3.jf.intel.com> User-Agent: StGit/0.17.1-9-g687f MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Update the definition of memcpy_from_pmem() to return 0 or a negative error code. Implement x86/arch_memcpy_from_pmem() with memcpy_mcsafe(). Cc: Borislav Petkov Cc: Ingo Molnar Cc: Tony Luck Cc: Thomas Gleixner Cc: Andy Lutomirski Cc: Peter Zijlstra Cc: Andrew Morton Cc: Linus Torvalds Reviewed-by: Ross Zwisler Signed-off-by: Dan Williams --- arch/x86/include/asm/pmem.h | 9 +++++++++ drivers/nvdimm/pmem.c | 4 ++-- include/linux/pmem.h | 21 +++++++++++++++------ 3 files changed, 26 insertions(+), 8 deletions(-) diff --git a/arch/x86/include/asm/pmem.h b/arch/x86/include/asm/pmem.h index bf8b35d2035a..fbc5e92e1ecc 100644 --- a/arch/x86/include/asm/pmem.h +++ b/arch/x86/include/asm/pmem.h @@ -47,6 +47,15 @@ static inline void arch_memcpy_to_pmem(void __pmem *dst, const void *src, BUG(); } +static inline int arch_memcpy_from_pmem(void *dst, const void __pmem *src, + size_t n) +{ + if (static_cpu_has(X86_FEATURE_MCE_RECOVERY)) + return memcpy_mcsafe(dst, (void __force *) src, n); + memcpy(dst, (void __force *) src, n); + return 0; +} + /** * arch_wmb_pmem - synchronize writes to persistent memory * diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c index ca5721c306bb..cc31c6f1f88e 100644 --- a/drivers/nvdimm/pmem.c +++ b/drivers/nvdimm/pmem.c @@ -99,7 +99,7 @@ static int pmem_do_bvec(struct pmem_device *pmem, struct page *page, if (unlikely(bad_pmem)) rc = -EIO; else { - memcpy_from_pmem(mem + off, pmem_addr, len); + rc = memcpy_from_pmem(mem + off, pmem_addr, len); flush_dcache_page(page); } } else { @@ -295,7 +295,7 @@ static int pmem_rw_bytes(struct nd_namespace_common *ndns, if (unlikely(is_bad_pmem(&pmem->bb, offset / 512, sz_align))) return -EIO; - memcpy_from_pmem(buf, pmem->virt_addr + offset, size); + return memcpy_from_pmem(buf, pmem->virt_addr + offset, size); } else { memcpy_to_pmem(pmem->virt_addr + offset, buf, size); wmb_pmem(); diff --git a/include/linux/pmem.h b/include/linux/pmem.h index 3ec5309e29f3..cc948191a653 100644 --- a/include/linux/pmem.h +++ b/include/linux/pmem.h @@ -42,6 +42,12 @@ static inline void arch_memcpy_to_pmem(void __pmem *dst, const void *src, BUG(); } +static inline int arch_memcpy_from_pmem(void *dst, const void __pmem *src, + size_t n) +{ + BUG(); +} + static inline size_t arch_copy_from_iter_pmem(void __pmem *addr, size_t bytes, struct iov_iter *i) { @@ -66,14 +72,17 @@ static inline void arch_invalidate_pmem(void __pmem *addr, size_t size) #endif /* - * Architectures that define ARCH_HAS_PMEM_API must provide - * implementations for arch_memcpy_to_pmem(), arch_wmb_pmem(), - * arch_copy_from_iter_pmem(), arch_clear_pmem(), arch_wb_cache_pmem() - * and arch_has_wmb_pmem(). + * memcpy_from_pmem - read from persistent memory with error handling + * @dst: destination buffer + * @src: source buffer + * @size: transfer length + * + * Returns 0 on success negative error code on failure. */ -static inline void memcpy_from_pmem(void *dst, void __pmem const *src, size_t size) +static inline int memcpy_from_pmem(void *dst, void __pmem const *src, + size_t size) { - memcpy(dst, (void __force const *) src, size); + return arch_memcpy_from_pmem(dst, src, size); } static inline bool arch_has_pmem_api(void)