From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8DEAC3537FB for ; Fri, 4 Sep 2026 13:18:16 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788527899; cv=none; b=qdp/3DaroEl0OBN0panRiQSZDzipo9zmhVaFHCu3ZLYmkvF/6/k13ixXyNONVUNo4lc4MZeG4jnaZnrU1g4VpicDApjd553EjmvFA2WBgVP5yrfWOhByw0bSSkkABdkOwupYYp1tgizUjYke2HyFufmYy6AK7SfszTE7/IML4W8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788527899; c=relaxed/simple; bh=YbUMkZUBwGeCT1r3KFxf3rMkd8Zto7/aTC3CD1SFDQc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=k/uTbWD8RnKOMcQqLPFbeHW1Atnqoo78eyVc9bIcz8YEbbemMBL8R27Hpa7serDzEQTWhSMCwp3EponsdFO5hwRGk5d7Ed8L/9nqtLLZJJPe9kY2SHp/dp3ubbtJpn5mvzwnVDxyt0ec+Xw6pKvP+Cdp8+pg24byqKtxfD64UQ4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=YRVpG+7m; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="YRVpG+7m" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4A1231F00A3F; Fri, 4 Sep 2026 13:18:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1788527894; bh=bxuM8/MHbuTZO1Qu0wEHqkb39aVANKDgTYnt52w4BbM=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=YRVpG+7mvNQwQVDMn7Cm7uSFjUuydj0QTwph7BRjWfga7olugGe+CFPjFmlLNCxdD GwDtcG/jgyw2Qth0TXZ9U7wbAX02Jagw8eSi57wET5Y3Aw2lPp32BvRISXNxPPgm3x SPNsjqBtImvCRML7f/19YU6mo7An53i4C2znx1lkv/zwDFcIV4G5deMG5fIzBkYWYx eTCKfW/VVNrkk4Gdt4M+mf5l6RRcrBx+jv12kE2Rd890aHALYHxPRgOQ7BiIxNjLGs WIXcrXHWh0GrRL8Wlg12Dbidpw33ZNKZF5vYbsYVgWaxiR/g0+MvW4Y4nu9A9XzlN9 30847PWqszG8Q== From: Sasha Levin To: stable@vger.kernel.org Cc: "Vishal Moola (Oracle)" , Oscar Salvador , "Matthew Wilcox (Oracle)" , Muchun Song , Andrew Morton , Sasha Levin Subject: [PATCH 6.6.y 3/6] hugetlb: convert hugetlb_wp() to use struct vm_fault Date: Fri, 4 Sep 2026 09:18:06 -0400 Message-ID: <20260904131809.503371-3-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260904131809.503371-1-sashal@kernel.org> References: <2026090314-mumps-septum-7049@gregkh> <20260904131809.503371-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: "Vishal Moola (Oracle)" [ Upstream commit bd722058e34de4857bc554e786b7f41c747ad894 ] hugetlb_wp() can use the struct vm_fault passed in from hugetlb_fault(). This alleviates the stack by consolidating 5 variables into a single struct. [vishal.moola@gmail.com: simplify hugetlb_wp() arguments] Link: https://lkml.kernel.org/r/ZhQtoFNZBNwBCeXn@fedora Link: https://lkml.kernel.org/r/20240401202651.31440-4-vishal.moola@gmail.com Signed-off-by: Vishal Moola (Oracle) Reviewed-by: Oscar Salvador Cc: Matthew Wilcox (Oracle) Cc: Muchun Song Signed-off-by: Andrew Morton Stable-dep-of: e87df0d5d696 ("mm/page_vma_mapped: use huge_ptep_get() for hugetlb") Signed-off-by: Sasha Levin --- mm/hugetlb.c | 65 ++++++++++++++++++++++++++-------------------------- 1 file changed, 33 insertions(+), 32 deletions(-) diff --git a/mm/hugetlb.c b/mm/hugetlb.c index a9757b11b7c49..271f42eb53ac9 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -5563,18 +5563,18 @@ static void unmap_ref_private(struct mm_struct *mm, struct vm_area_struct *vma, * cannot race with other handlers or page migration. * Keep the pte_same checks anyway to make transition from the mutex easier. */ -static vm_fault_t hugetlb_wp(struct mm_struct *mm, struct vm_area_struct *vma, - unsigned long address, pte_t *ptep, unsigned int flags, - struct folio *pagecache_folio, spinlock_t *ptl) +static vm_fault_t hugetlb_wp(struct folio *pagecache_folio, + struct vm_fault *vmf) { - const bool unshare = flags & FAULT_FLAG_UNSHARE; - pte_t pte = huge_ptep_get(ptep); + struct vm_area_struct *vma = vmf->vma; + struct mm_struct *mm = vma->vm_mm; + const bool unshare = vmf->flags & FAULT_FLAG_UNSHARE; + pte_t pte = huge_ptep_get(vmf->pte); struct hstate *h = hstate_vma(vma); struct folio *old_folio; struct folio *new_folio; int outside_reserve = 0; vm_fault_t ret = 0; - unsigned long haddr = address & huge_page_mask(h); struct mmu_notifier_range range; /* @@ -5597,7 +5597,7 @@ static vm_fault_t hugetlb_wp(struct mm_struct *mm, struct vm_area_struct *vma, /* Let's take out MAP_SHARED mappings first. */ if (vma->vm_flags & VM_MAYSHARE) { - set_huge_ptep_writable(vma, haddr, ptep); + set_huge_ptep_writable(vma, vmf->address, vmf->pte); return 0; } @@ -5614,7 +5614,7 @@ static vm_fault_t hugetlb_wp(struct mm_struct *mm, struct vm_area_struct *vma, if (!PageAnonExclusive(&old_folio->page)) page_move_anon_rmap(&old_folio->page, vma); if (likely(!unshare)) - set_huge_ptep_writable(vma, haddr, ptep); + set_huge_ptep_writable(vma, vmf->address, vmf->pte); delayacct_wpcopy_end(); return 0; @@ -5641,8 +5641,8 @@ static vm_fault_t hugetlb_wp(struct mm_struct *mm, struct vm_area_struct *vma, * Drop page table lock as buddy allocator may be called. It will * be acquired again before returning to the caller, as expected. */ - spin_unlock(ptl); - new_folio = alloc_hugetlb_folio(vma, haddr, outside_reserve); + spin_unlock(vmf->ptl); + new_folio = alloc_hugetlb_folio(vma, vmf->address, outside_reserve); if (IS_ERR(new_folio)) { /* @@ -5667,19 +5667,21 @@ static vm_fault_t hugetlb_wp(struct mm_struct *mm, struct vm_area_struct *vma, * * Reacquire both after unmap operation. */ - idx = vma_hugecache_offset(h, vma, haddr); + idx = vma_hugecache_offset(h, vma, vmf->address); hash = hugetlb_fault_mutex_hash(mapping, idx); hugetlb_vma_unlock_read(vma); mutex_unlock(&hugetlb_fault_mutex_table[hash]); - unmap_ref_private(mm, vma, &old_folio->page, haddr); + unmap_ref_private(mm, vma, &old_folio->page, + vmf->address); mutex_lock(&hugetlb_fault_mutex_table[hash]); hugetlb_vma_lock_read(vma); - spin_lock(ptl); - ptep = hugetlb_walk(vma, haddr, huge_page_size(h)); - if (likely(ptep && - pte_same(huge_ptep_get(ptep), pte))) + spin_lock(vmf->ptl); + vmf->pte = hugetlb_walk(vma, vmf->address, + huge_page_size(h)); + if (likely(vmf->pte && + pte_same(huge_ptep_get(vmf->pte), pte))) goto retry_avoidcopy; /* * race occurs while re-acquiring page table @@ -5702,37 +5704,38 @@ static vm_fault_t hugetlb_wp(struct mm_struct *mm, struct vm_area_struct *vma, goto out_release_all; } - if (copy_user_large_folio(new_folio, old_folio, address, vma)) { + if (copy_user_large_folio(new_folio, old_folio, vmf->real_address, vma)) { ret = VM_FAULT_HWPOISON_LARGE; goto out_release_all; } __folio_mark_uptodate(new_folio); - mmu_notifier_range_init(&range, MMU_NOTIFY_CLEAR, 0, mm, haddr, - haddr + huge_page_size(h)); + mmu_notifier_range_init(&range, MMU_NOTIFY_CLEAR, 0, mm, vmf->address, + vmf->address + huge_page_size(h)); mmu_notifier_invalidate_range_start(&range); /* * Retake the page table lock to check for racing updates * before the page tables are altered */ - spin_lock(ptl); - ptep = hugetlb_walk(vma, haddr, huge_page_size(h)); - if (likely(ptep && pte_same(huge_ptep_get(ptep), pte))) { + spin_lock(vmf->ptl); + vmf->pte = hugetlb_walk(vma, vmf->address, huge_page_size(h)); + if (likely(vmf->pte && pte_same(huge_ptep_get(vmf->pte), pte))) { pte_t newpte = make_huge_pte(vma, &new_folio->page, !unshare); /* Break COW or unshare */ - huge_ptep_clear_flush(vma, haddr, ptep); + huge_ptep_clear_flush(vma, vmf->address, vmf->pte); page_remove_rmap(&old_folio->page, vma, true); - hugepage_add_new_anon_rmap(new_folio, vma, haddr); + hugepage_add_new_anon_rmap(new_folio, vma, vmf->address); if (huge_pte_uffd_wp(pte)) newpte = huge_pte_mkuffd_wp(newpte); - set_huge_pte_at(mm, haddr, ptep, newpte, huge_page_size(h)); + set_huge_pte_at(mm, vmf->address, vmf->pte, newpte, + huge_page_size(h)); folio_set_hugetlb_migratable(new_folio); /* Make the old page be freed below */ new_folio = old_folio; } - spin_unlock(ptl); + spin_unlock(vmf->ptl); mmu_notifier_invalidate_range_end(&range); out_release_all: /* @@ -5740,12 +5743,12 @@ static vm_fault_t hugetlb_wp(struct mm_struct *mm, struct vm_area_struct *vma, * unshare) */ if (new_folio != old_folio) - restore_reserve_on_error(h, vma, haddr, new_folio); + restore_reserve_on_error(h, vma, vmf->address, new_folio); folio_put(new_folio); out_release_old: folio_put(old_folio); - spin_lock(ptl); /* Caller expects lock to be held */ + spin_lock(vmf->ptl); /* Caller expects lock to be held */ delayacct_wpcopy_end(); return ret; @@ -6030,8 +6033,7 @@ static vm_fault_t hugetlb_no_page(struct address_space *mapping, hugetlb_count_add(pages_per_huge_page(h), mm); if ((vmf->flags & FAULT_FLAG_WRITE) && !(vma->vm_flags & VM_SHARED)) { /* Optimization, do the COW without a second fault */ - ret = hugetlb_wp(mm, vma, vmf->real_address, vmf->pte, - vmf->flags, folio, vmf->ptl); + ret = hugetlb_wp(folio, vmf); } spin_unlock(vmf->ptl); @@ -6242,8 +6244,7 @@ vm_fault_t hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma, if (flags & (FAULT_FLAG_WRITE|FAULT_FLAG_UNSHARE)) { if (!huge_pte_write(vmf.orig_pte)) { - ret = hugetlb_wp(mm, vma, address, vmf.pte, flags, - pagecache_folio, vmf.ptl); + ret = hugetlb_wp(pagecache_folio, &vmf); goto out_put_page; } else if (likely(flags & FAULT_FLAG_WRITE)) { vmf.orig_pte = huge_pte_mkdirty(vmf.orig_pte); -- 2.53.0