From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932292AbeCPUg0 (ORCPT ); Fri, 16 Mar 2018 16:36:26 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:42922 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752568AbeCPUf7 (ORCPT ); Fri, 16 Mar 2018 16:35:59 -0400 From: jglisse@redhat.com To: linux-mm@kvack.org Cc: Andrew Morton , linux-kernel@vger.kernel.org, =?UTF-8?q?J=C3=A9r=C3=B4me=20Glisse?= , Evgeny Baskakov , Ralph Campbell , Mark Hairgrove , John Hubbard Subject: [PATCH 13/14] mm/hmm: change hmm_vma_fault() to allow write fault on page basis Date: Fri, 16 Mar 2018 16:35:51 -0400 Message-Id: <20180316203552.4155-4-jglisse@redhat.com> In-Reply-To: <20180316203552.4155-1-jglisse@redhat.com> References: <20180316203552.4155-1-jglisse@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Jérôme Glisse This change hmm_vma_fault() to not take a global write fault flag for a range but instead rely on caller to populate HMM pfns array with proper fault flag ie HMM_PFN_VALID if driver want read fault for that address or HMM_PFN_VALID and HMM_PFN_WRITE for write. Moreover by setting HMM_PFN_DEVICE_PRIVATE the device driver can ask for device private memory to be migrated back to system memory through page fault. This is more flexible API and it better reflects how device handles and reports fault. Signed-off-by: Jérôme Glisse Cc: Evgeny Baskakov Cc: Ralph Campbell Cc: Mark Hairgrove Cc: John Hubbard --- include/linux/hmm.h | 2 +- mm/hmm.c | 150 +++++++++++++++++++++++++++++++++++++++++----------- 2 files changed, 119 insertions(+), 33 deletions(-) diff --git a/include/linux/hmm.h b/include/linux/hmm.h index 78018b3e7a9f..ee758c4e4bec 100644 --- a/include/linux/hmm.h +++ b/include/linux/hmm.h @@ -317,7 +317,7 @@ bool hmm_vma_range_done(struct hmm_range *range); * * See the function description in mm/hmm.c for further documentation. */ -int hmm_vma_fault(struct hmm_range *range, bool write, bool block); +int hmm_vma_fault(struct hmm_range *range, bool block); #endif /* IS_ENABLED(CONFIG_HMM_MIRROR) */ diff --git a/mm/hmm.c b/mm/hmm.c index 40aaa757f262..0ea530d0fd1d 100644 --- a/mm/hmm.c +++ b/mm/hmm.c @@ -256,12 +256,10 @@ struct hmm_vma_walk { unsigned long last; bool fault; bool block; - bool write; }; -static int hmm_vma_do_fault(struct mm_walk *walk, - unsigned long addr, - uint64_t *pfn) +static int hmm_vma_do_fault(struct mm_walk *walk, unsigned long addr, + bool write_fault, uint64_t *pfn) { unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_REMOTE; struct hmm_vma_walk *hmm_vma_walk = walk->private; @@ -269,7 +267,7 @@ static int hmm_vma_do_fault(struct mm_walk *walk, int r; flags |= hmm_vma_walk->block ? 0 : FAULT_FLAG_ALLOW_RETRY; - flags |= hmm_vma_walk->write ? FAULT_FLAG_WRITE : 0; + flags |= write_fault ? FAULT_FLAG_WRITE : 0; r = handle_mm_fault(vma, addr, flags); if (r & VM_FAULT_RETRY) return -EBUSY; @@ -301,15 +299,17 @@ static int hmm_pfns_bad(unsigned long addr, * hmm_vma_walk_hole() - handle a range back by no pmd or no pte * @start: range virtual start address (inclusive) * @end: range virtual end address (exclusive) + * @fault: should we fault or not ? + * @write_fault: write fault ? * @walk: mm_walk structure * Returns: 0 on success, -EAGAIN after page fault, or page fault error * * This is an helper call whenever pmd_none() or pte_none() returns true * or when there is no directory covering the range. */ -static int hmm_vma_walk_hole(unsigned long addr, - unsigned long end, - struct mm_walk *walk) +static int hmm_vma_walk_hole_(unsigned long addr, unsigned long end, + bool fault, bool write_fault, + struct mm_walk *walk) { struct hmm_vma_walk *hmm_vma_walk = walk->private; struct hmm_range *range = hmm_vma_walk->range; @@ -320,16 +320,89 @@ static int hmm_vma_walk_hole(unsigned long addr, i = (addr - range->start) >> PAGE_SHIFT; for (; addr < end; addr += PAGE_SIZE, i++) { pfns[i] = 0; - if (hmm_vma_walk->fault) { + if (fault || write_fault) { int ret; - ret = hmm_vma_do_fault(walk, addr, &pfns[i]); + ret = hmm_vma_do_fault(walk, addr, write_fault, + &pfns[i]); if (ret != -EAGAIN) return ret; } } - return hmm_vma_walk->fault ? -EAGAIN : 0; + return (fault || write_fault) ? -EAGAIN : 0; +} + +static inline void hmm_pte_need_fault(const struct hmm_vma_walk *hmm_vma_walk, + uint64_t pfns, uint64_t cpu_flags, + bool *fault, bool *write_fault) +{ + *fault = *write_fault = false; + if (!hmm_vma_walk->fault) + return; + + /* We aren't ask to do anything ... */ + if (!(pfns & HMM_PFN_VALID)) + return; + /* If CPU page table is not valid then we need to fault */ + *fault = cpu_flags & HMM_PFN_VALID; + /* Need to write fault ? */ + if ((pfns & HMM_PFN_WRITE) && !(cpu_flags & HMM_PFN_WRITE)) { + *fault = *write_fault = false; + return; + } + /* Do we fault on device memory ? */ + if ((pfns & HMM_PFN_DEVICE_PRIVATE) && + (cpu_flags & HMM_PFN_DEVICE_PRIVATE)) { + *write_fault = pfns & HMM_PFN_WRITE; + *fault = true; + } +} + +static void hmm_range_need_fault(const struct hmm_vma_walk *hmm_vma_walk, + const uint64_t *pfns, unsigned long npages, + uint64_t cpu_flags, bool *fault, + bool *write_fault) +{ + unsigned long i; + + if (!hmm_vma_walk->fault) { + *fault = *write_fault = false; + return; + } + + for (i = 0; i < npages; ++i) { + hmm_pte_need_fault(hmm_vma_walk, pfns[i], cpu_flags, + fault, write_fault); + if ((*fault) || (*write_fault)) + return; + } +} + +static int hmm_vma_walk_hole(unsigned long addr, unsigned long end, + struct mm_walk *walk) +{ + struct hmm_vma_walk *hmm_vma_walk = walk->private; + struct hmm_range *range = hmm_vma_walk->range; + bool fault, write_fault; + unsigned long i, npages; + uint64_t *pfns; + + i = (addr - range->start) >> PAGE_SHIFT; + npages = (end - addr) >> PAGE_SHIFT; + pfns = &range->pfns[i]; + hmm_range_need_fault(hmm_vma_walk, pfns, npages, + 0, &fault, &write_fault); + return hmm_vma_walk_hole_(addr, end, fault, write_fault, walk); +} + +static inline uint64_t pmd_to_hmm_pfn_flags(pmd_t pmd) +{ + if (pmd_protnone(pmd)) + return 0; + return pmd_write(pmd) ? HMM_PFN_VALID | + HMM_PFN_WRITE : + HMM_PFN_VALID; } static int hmm_vma_handle_pmd(struct mm_walk *walk, @@ -339,14 +412,17 @@ static int hmm_vma_handle_pmd(struct mm_walk *walk, pmd_t pmd) { struct hmm_vma_walk *hmm_vma_walk = walk->private; - unsigned long pfn, i; - uint64_t flag = 0; + unsigned long pfn, npages, i; + uint64_t flag = 0, cpu_flags; + bool fault, write_fault; - if (pmd_protnone(pmd)) - return hmm_vma_walk_hole(addr, end, walk); + npages = (end - addr) >> PAGE_SHIFT; + cpu_flags = pmd_to_hmm_pfn_flags(pmd); + hmm_range_need_fault(hmm_vma_walk, pfns, npages, cpu_flags, + &fault, &write_fault); - if ((hmm_vma_walk->fault & hmm_vma_walk->write) && !pmd_write(pmd)) - return hmm_vma_walk_hole(addr, end, walk); + if (pmd_protnone(pmd) || fault || write_fault) + return hmm_vma_walk_hole_(addr, end, fault, write_fault, walk); pfn = pmd_pfn(pmd) + pte_index(addr); flag |= pmd_write(pmd) ? HMM_PFN_WRITE : 0; @@ -356,19 +432,33 @@ static int hmm_vma_handle_pmd(struct mm_walk *walk, return 0; } +static inline uint64_t pte_to_hmm_pfn_flags(pte_t pte) +{ + if (pte_none(pte) || !pte_present(pte)) + return 0; + return pte_write(pte) ? HMM_PFN_VALID | + HMM_PFN_WRITE : + HMM_PFN_VALID; +} + static int hmm_vma_handle_pte(struct mm_walk *walk, unsigned long addr, unsigned long end, pmd_t *pmdp, pte_t *ptep, uint64_t *pfns) { struct hmm_vma_walk *hmm_vma_walk = walk->private; struct vm_area_struct *vma = walk->vma; + bool fault, write_fault; + uint64_t cpu_flags; pte_t pte = *ptep; *pfns = 0; + cpu_flags = pte_to_hmm_pfn_flags(pte); + hmm_pte_need_fault(hmm_vma_walk, *pfns, cpu_flags, + &fault, &write_fault); if (pte_none(pte)) { *pfns = 0; - if (hmm_vma_walk->fault) + if (fault || write_fault) goto fault; return 0; } @@ -377,7 +467,7 @@ static int hmm_vma_handle_pte(struct mm_walk *walk, unsigned long addr, swp_entry_t entry = pte_to_swp_entry(pte); if (!non_swap_entry(entry)) { - if (hmm_vma_walk->fault) + if (fault || write_fault) goto fault; return 0; } @@ -387,21 +477,20 @@ static int hmm_vma_handle_pte(struct mm_walk *walk, unsigned long addr, * device and report anything else as error. */ if (is_device_private_entry(entry)) { + cpu_flags = HMM_PFN_VALID | HMM_PFN_DEVICE_PRIVATE; + cpu_flags |= is_write_device_private_entry(entry) ? + HMM_PFN_WRITE : 0; *pfns = hmm_pfn_from_pfn(swp_offset(entry)); - if (is_write_device_private_entry(entry)) { - *pfns |= HMM_PFN_WRITE; - } else if ((hmm_vma_walk->fault & hmm_vma_walk->write)) - goto fault; *pfns |= HMM_PFN_DEVICE_PRIVATE; return 0; } if (is_migration_entry(entry)) { - if (hmm_vma_walk->fault) { + if (fault || write_fault) { pte_unmap(ptep); hmm_vma_walk->last = addr; migration_entry_wait(vma->vm_mm, - pmdp, addr); + pmdp, addr); return -EAGAIN; } return 0; @@ -412,17 +501,16 @@ static int hmm_vma_handle_pte(struct mm_walk *walk, unsigned long addr, return -EFAULT; } - if ((hmm_vma_walk->fault & hmm_vma_walk->write) && !pte_write(pte)) + if (fault || write_fault) goto fault; - *pfns = hmm_pfn_from_pfn(pte_pfn(pte)); - *pfns |= pte_write(pte) ? HMM_PFN_WRITE : 0; + *pfns = hmm_pfn_from_pfn(pte_pfn(pte)) | cpu_flags; return 0; fault: pte_unmap(ptep); /* Fault all pages in range if ask for */ - return hmm_vma_walk_hole(addr, end, walk); + return hmm_vma_walk_hole_(addr, end, fault, write_fault, walk); } static int hmm_vma_walk_pmd(pmd_t *pmdp, @@ -642,7 +730,6 @@ EXPORT_SYMBOL(hmm_vma_range_done); /* * hmm_vma_fault() - try to fault some address in a virtual address range * @range: range being faulted and all needed informations - * @write: is it a write fault * @block: allow blocking on fault (if true it sleeps and do not drop mmap_sem) * Returns: 0 success, error otherwise (-EAGAIN means mmap_sem have been drop) * @@ -684,7 +771,7 @@ EXPORT_SYMBOL(hmm_vma_range_done); * * YOU HAVE BEEN WARNED ! */ -int hmm_vma_fault(struct hmm_range *range, bool write, bool block) +int hmm_vma_fault(struct hmm_range *range, bool block) { struct vm_area_struct *vma = range->vma; unsigned long start = range->start; @@ -732,7 +819,6 @@ int hmm_vma_fault(struct hmm_range *range, bool write, bool block) } hmm_vma_walk.fault = true; - hmm_vma_walk.write = write; hmm_vma_walk.block = block; hmm_vma_walk.range = range; mm_walk.private = &hmm_vma_walk; -- 2.14.3 From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qt0-f200.google.com (mail-qt0-f200.google.com [209.85.216.200]) by kanga.kvack.org (Postfix) with ESMTP id 8A0A36B026A for ; Fri, 16 Mar 2018 16:35:59 -0400 (EDT) Received: by mail-qt0-f200.google.com with SMTP id z1so7424767qtz.12 for ; Fri, 16 Mar 2018 13:35:59 -0700 (PDT) Received: from mx1.redhat.com (mx3-rdu2.redhat.com. [66.187.233.73]) by mx.google.com with ESMTPS id n66si8280922qkl.46.2018.03.16.13.35.58 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 16 Mar 2018 13:35:58 -0700 (PDT) From: jglisse@redhat.com Subject: [PATCH 13/14] mm/hmm: change hmm_vma_fault() to allow write fault on page basis Date: Fri, 16 Mar 2018 16:35:51 -0400 Message-Id: <20180316203552.4155-4-jglisse@redhat.com> In-Reply-To: <20180316203552.4155-1-jglisse@redhat.com> References: <20180316203552.4155-1-jglisse@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: owner-linux-mm@kvack.org List-ID: To: linux-mm@kvack.org Cc: Andrew Morton , linux-kernel@vger.kernel.org, =?UTF-8?q?J=C3=A9r=C3=B4me=20Glisse?= , Evgeny Baskakov , Ralph Campbell , Mark Hairgrove , John Hubbard From: JA(C)rA'me Glisse This change hmm_vma_fault() to not take a global write fault flag for a range but instead rely on caller to populate HMM pfns array with proper fault flag ie HMM_PFN_VALID if driver want read fault for that address or HMM_PFN_VALID and HMM_PFN_WRITE for write. Moreover by setting HMM_PFN_DEVICE_PRIVATE the device driver can ask for device private memory to be migrated back to system memory through page fault. This is more flexible API and it better reflects how device handles and reports fault. Signed-off-by: JA(C)rA'me Glisse Cc: Evgeny Baskakov Cc: Ralph Campbell Cc: Mark Hairgrove Cc: John Hubbard --- include/linux/hmm.h | 2 +- mm/hmm.c | 150 +++++++++++++++++++++++++++++++++++++++++----------- 2 files changed, 119 insertions(+), 33 deletions(-) diff --git a/include/linux/hmm.h b/include/linux/hmm.h index 78018b3e7a9f..ee758c4e4bec 100644 --- a/include/linux/hmm.h +++ b/include/linux/hmm.h @@ -317,7 +317,7 @@ bool hmm_vma_range_done(struct hmm_range *range); * * See the function description in mm/hmm.c for further documentation. */ -int hmm_vma_fault(struct hmm_range *range, bool write, bool block); +int hmm_vma_fault(struct hmm_range *range, bool block); #endif /* IS_ENABLED(CONFIG_HMM_MIRROR) */ diff --git a/mm/hmm.c b/mm/hmm.c index 40aaa757f262..0ea530d0fd1d 100644 --- a/mm/hmm.c +++ b/mm/hmm.c @@ -256,12 +256,10 @@ struct hmm_vma_walk { unsigned long last; bool fault; bool block; - bool write; }; -static int hmm_vma_do_fault(struct mm_walk *walk, - unsigned long addr, - uint64_t *pfn) +static int hmm_vma_do_fault(struct mm_walk *walk, unsigned long addr, + bool write_fault, uint64_t *pfn) { unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_REMOTE; struct hmm_vma_walk *hmm_vma_walk = walk->private; @@ -269,7 +267,7 @@ static int hmm_vma_do_fault(struct mm_walk *walk, int r; flags |= hmm_vma_walk->block ? 0 : FAULT_FLAG_ALLOW_RETRY; - flags |= hmm_vma_walk->write ? FAULT_FLAG_WRITE : 0; + flags |= write_fault ? FAULT_FLAG_WRITE : 0; r = handle_mm_fault(vma, addr, flags); if (r & VM_FAULT_RETRY) return -EBUSY; @@ -301,15 +299,17 @@ static int hmm_pfns_bad(unsigned long addr, * hmm_vma_walk_hole() - handle a range back by no pmd or no pte * @start: range virtual start address (inclusive) * @end: range virtual end address (exclusive) + * @fault: should we fault or not ? + * @write_fault: write fault ? * @walk: mm_walk structure * Returns: 0 on success, -EAGAIN after page fault, or page fault error * * This is an helper call whenever pmd_none() or pte_none() returns true * or when there is no directory covering the range. */ -static int hmm_vma_walk_hole(unsigned long addr, - unsigned long end, - struct mm_walk *walk) +static int hmm_vma_walk_hole_(unsigned long addr, unsigned long end, + bool fault, bool write_fault, + struct mm_walk *walk) { struct hmm_vma_walk *hmm_vma_walk = walk->private; struct hmm_range *range = hmm_vma_walk->range; @@ -320,16 +320,89 @@ static int hmm_vma_walk_hole(unsigned long addr, i = (addr - range->start) >> PAGE_SHIFT; for (; addr < end; addr += PAGE_SIZE, i++) { pfns[i] = 0; - if (hmm_vma_walk->fault) { + if (fault || write_fault) { int ret; - ret = hmm_vma_do_fault(walk, addr, &pfns[i]); + ret = hmm_vma_do_fault(walk, addr, write_fault, + &pfns[i]); if (ret != -EAGAIN) return ret; } } - return hmm_vma_walk->fault ? -EAGAIN : 0; + return (fault || write_fault) ? -EAGAIN : 0; +} + +static inline void hmm_pte_need_fault(const struct hmm_vma_walk *hmm_vma_walk, + uint64_t pfns, uint64_t cpu_flags, + bool *fault, bool *write_fault) +{ + *fault = *write_fault = false; + if (!hmm_vma_walk->fault) + return; + + /* We aren't ask to do anything ... */ + if (!(pfns & HMM_PFN_VALID)) + return; + /* If CPU page table is not valid then we need to fault */ + *fault = cpu_flags & HMM_PFN_VALID; + /* Need to write fault ? */ + if ((pfns & HMM_PFN_WRITE) && !(cpu_flags & HMM_PFN_WRITE)) { + *fault = *write_fault = false; + return; + } + /* Do we fault on device memory ? */ + if ((pfns & HMM_PFN_DEVICE_PRIVATE) && + (cpu_flags & HMM_PFN_DEVICE_PRIVATE)) { + *write_fault = pfns & HMM_PFN_WRITE; + *fault = true; + } +} + +static void hmm_range_need_fault(const struct hmm_vma_walk *hmm_vma_walk, + const uint64_t *pfns, unsigned long npages, + uint64_t cpu_flags, bool *fault, + bool *write_fault) +{ + unsigned long i; + + if (!hmm_vma_walk->fault) { + *fault = *write_fault = false; + return; + } + + for (i = 0; i < npages; ++i) { + hmm_pte_need_fault(hmm_vma_walk, pfns[i], cpu_flags, + fault, write_fault); + if ((*fault) || (*write_fault)) + return; + } +} + +static int hmm_vma_walk_hole(unsigned long addr, unsigned long end, + struct mm_walk *walk) +{ + struct hmm_vma_walk *hmm_vma_walk = walk->private; + struct hmm_range *range = hmm_vma_walk->range; + bool fault, write_fault; + unsigned long i, npages; + uint64_t *pfns; + + i = (addr - range->start) >> PAGE_SHIFT; + npages = (end - addr) >> PAGE_SHIFT; + pfns = &range->pfns[i]; + hmm_range_need_fault(hmm_vma_walk, pfns, npages, + 0, &fault, &write_fault); + return hmm_vma_walk_hole_(addr, end, fault, write_fault, walk); +} + +static inline uint64_t pmd_to_hmm_pfn_flags(pmd_t pmd) +{ + if (pmd_protnone(pmd)) + return 0; + return pmd_write(pmd) ? HMM_PFN_VALID | + HMM_PFN_WRITE : + HMM_PFN_VALID; } static int hmm_vma_handle_pmd(struct mm_walk *walk, @@ -339,14 +412,17 @@ static int hmm_vma_handle_pmd(struct mm_walk *walk, pmd_t pmd) { struct hmm_vma_walk *hmm_vma_walk = walk->private; - unsigned long pfn, i; - uint64_t flag = 0; + unsigned long pfn, npages, i; + uint64_t flag = 0, cpu_flags; + bool fault, write_fault; - if (pmd_protnone(pmd)) - return hmm_vma_walk_hole(addr, end, walk); + npages = (end - addr) >> PAGE_SHIFT; + cpu_flags = pmd_to_hmm_pfn_flags(pmd); + hmm_range_need_fault(hmm_vma_walk, pfns, npages, cpu_flags, + &fault, &write_fault); - if ((hmm_vma_walk->fault & hmm_vma_walk->write) && !pmd_write(pmd)) - return hmm_vma_walk_hole(addr, end, walk); + if (pmd_protnone(pmd) || fault || write_fault) + return hmm_vma_walk_hole_(addr, end, fault, write_fault, walk); pfn = pmd_pfn(pmd) + pte_index(addr); flag |= pmd_write(pmd) ? HMM_PFN_WRITE : 0; @@ -356,19 +432,33 @@ static int hmm_vma_handle_pmd(struct mm_walk *walk, return 0; } +static inline uint64_t pte_to_hmm_pfn_flags(pte_t pte) +{ + if (pte_none(pte) || !pte_present(pte)) + return 0; + return pte_write(pte) ? HMM_PFN_VALID | + HMM_PFN_WRITE : + HMM_PFN_VALID; +} + static int hmm_vma_handle_pte(struct mm_walk *walk, unsigned long addr, unsigned long end, pmd_t *pmdp, pte_t *ptep, uint64_t *pfns) { struct hmm_vma_walk *hmm_vma_walk = walk->private; struct vm_area_struct *vma = walk->vma; + bool fault, write_fault; + uint64_t cpu_flags; pte_t pte = *ptep; *pfns = 0; + cpu_flags = pte_to_hmm_pfn_flags(pte); + hmm_pte_need_fault(hmm_vma_walk, *pfns, cpu_flags, + &fault, &write_fault); if (pte_none(pte)) { *pfns = 0; - if (hmm_vma_walk->fault) + if (fault || write_fault) goto fault; return 0; } @@ -377,7 +467,7 @@ static int hmm_vma_handle_pte(struct mm_walk *walk, unsigned long addr, swp_entry_t entry = pte_to_swp_entry(pte); if (!non_swap_entry(entry)) { - if (hmm_vma_walk->fault) + if (fault || write_fault) goto fault; return 0; } @@ -387,21 +477,20 @@ static int hmm_vma_handle_pte(struct mm_walk *walk, unsigned long addr, * device and report anything else as error. */ if (is_device_private_entry(entry)) { + cpu_flags = HMM_PFN_VALID | HMM_PFN_DEVICE_PRIVATE; + cpu_flags |= is_write_device_private_entry(entry) ? + HMM_PFN_WRITE : 0; *pfns = hmm_pfn_from_pfn(swp_offset(entry)); - if (is_write_device_private_entry(entry)) { - *pfns |= HMM_PFN_WRITE; - } else if ((hmm_vma_walk->fault & hmm_vma_walk->write)) - goto fault; *pfns |= HMM_PFN_DEVICE_PRIVATE; return 0; } if (is_migration_entry(entry)) { - if (hmm_vma_walk->fault) { + if (fault || write_fault) { pte_unmap(ptep); hmm_vma_walk->last = addr; migration_entry_wait(vma->vm_mm, - pmdp, addr); + pmdp, addr); return -EAGAIN; } return 0; @@ -412,17 +501,16 @@ static int hmm_vma_handle_pte(struct mm_walk *walk, unsigned long addr, return -EFAULT; } - if ((hmm_vma_walk->fault & hmm_vma_walk->write) && !pte_write(pte)) + if (fault || write_fault) goto fault; - *pfns = hmm_pfn_from_pfn(pte_pfn(pte)); - *pfns |= pte_write(pte) ? HMM_PFN_WRITE : 0; + *pfns = hmm_pfn_from_pfn(pte_pfn(pte)) | cpu_flags; return 0; fault: pte_unmap(ptep); /* Fault all pages in range if ask for */ - return hmm_vma_walk_hole(addr, end, walk); + return hmm_vma_walk_hole_(addr, end, fault, write_fault, walk); } static int hmm_vma_walk_pmd(pmd_t *pmdp, @@ -642,7 +730,6 @@ EXPORT_SYMBOL(hmm_vma_range_done); /* * hmm_vma_fault() - try to fault some address in a virtual address range * @range: range being faulted and all needed informations - * @write: is it a write fault * @block: allow blocking on fault (if true it sleeps and do not drop mmap_sem) * Returns: 0 success, error otherwise (-EAGAIN means mmap_sem have been drop) * @@ -684,7 +771,7 @@ EXPORT_SYMBOL(hmm_vma_range_done); * * YOU HAVE BEEN WARNED ! */ -int hmm_vma_fault(struct hmm_range *range, bool write, bool block) +int hmm_vma_fault(struct hmm_range *range, bool block) { struct vm_area_struct *vma = range->vma; unsigned long start = range->start; @@ -732,7 +819,6 @@ int hmm_vma_fault(struct hmm_range *range, bool write, bool block) } hmm_vma_walk.fault = true; - hmm_vma_walk.write = write; hmm_vma_walk.block = block; hmm_vma_walk.range = range; mm_walk.private = &hmm_vma_walk; -- 2.14.3