From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 2FA884C0417; Thu, 7 May 2026 20:22:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778185373; cv=none; b=MUMRNutOtpd4xfp/r2gwsu1jZGV+lehvobere1Wo37LhMgWn+Y3U31KfB0g/DM2HSQb2a1Jog0DkThtz5u7qZZsL2k07HcddtsjuxkqeTOVX9L6aroiDk8qhIYEO8XcFjXdXaBGQ6Z+kfy7xGF5TdrG1YqLNJr7WdgszT1GQ79A= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778185373; c=relaxed/simple; bh=pPQQU8ZquGDc5woI3IF9NwZh3hDz8qw/u9ovucBYlww=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=QRYVCEsfyoHdHJU3/H0EYO7rzRaCr0tHDWiY99kxZ2J8JIv/lCDJD0l4bJZQHmOeHIAxEOVwDSDf94PwgYtWT9JyzI09mWskk8uvOjk1s2rKzCUMlejUhZtNEvsH39owDFZIj2go9F3rKClguBrO3mTj+of+/i1XV4ikBZuxcFE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=fzvd6/UO; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="fzvd6/UO" Received: by smtp.kernel.org (Postfix) with ESMTPS id 0BC11C2BCC9; Thu, 7 May 2026 20:22:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1778185373; bh=pPQQU8ZquGDc5woI3IF9NwZh3hDz8qw/u9ovucBYlww=; h=From:Date:Subject:References:In-Reply-To:To:Cc:Reply-To:From; b=fzvd6/UOn3T/sQehRfu+1lMd8kE9n73lEEL6XOkOJn2OyiAFD292zjr0Hx0ISuEpl FEcLEhNABOO5HT+hOJ54V6Bljg0KpG3TJzhP/BG7ebOVCk0/aLlVrH8rJBhZxr/2ji l+/vJ9w00FcIyinWGnP6tqOKvgoaSvIbh7UfKvngcnDKIklAj1zXiZWYH1D8Wab1Jp KsWdA3ZPm1ojAz14Jun7i8OPzrkKcoIuzKipxhgeVlgyh2cNStHWXVXZ0QQPHSuAVd f9AuSNEqOt9prvLkfim3can4AbVbHjYj/eXhAbgVTaxZr9ZN337uWeLoBhqqKB7jXS TyPq5jJxr7kmQ== Received: from aws-us-west-2-korg-lkml-1.web.codeaurora.org (localhost.localdomain [127.0.0.1]) by smtp.lore.kernel.org (Postfix) with ESMTP id E8E0ACD343F; Thu, 7 May 2026 20:22:52 +0000 (UTC) From: Ackerley Tng via B4 Relay Date: Thu, 07 May 2026 13:22:56 -0700 Subject: [PATCH v6 37/43] KVM: selftests: Provide function to look up guest_memfd details from gpa Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20260507-gmem-inplace-conversion-v6-37-91ab5a8b19a4@google.com> References: <20260507-gmem-inplace-conversion-v6-0-91ab5a8b19a4@google.com> In-Reply-To: <20260507-gmem-inplace-conversion-v6-0-91ab5a8b19a4@google.com> To: aik@amd.com, andrew.jones@linux.dev, binbin.wu@linux.intel.com, brauner@kernel.org, chao.p.peng@linux.intel.com, david@kernel.org, ira.weiny@intel.com, jmattson@google.com, jthoughton@google.com, michael.roth@amd.com, oupton@kernel.org, pankaj.gupta@amd.com, qperret@google.com, rick.p.edgecombe@intel.com, rientjes@google.com, shivankg@amd.com, steven.price@arm.com, tabba@google.com, willy@infradead.org, wyihan@google.com, yan.y.zhao@intel.com, forkloop@google.com, pratyush@kernel.org, suzuki.poulose@arm.com, aneesh.kumar@kernel.org, liam@infradead.org, Paolo Bonzini , Sean Christopherson , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Steven Rostedt , Masami Hiramatsu , Mathieu Desnoyers , Jonathan Corbet , Shuah Khan , Shuah Khan , Vishal Annapurve , Andrew Morton , Chris Li , Kairui Song , Kemeng Shi , Nhat Pham , Baoquan He , Barry Song , Axel Rasmussen , Yuanchu Xie , Wei Xu , Youngjun Park , Qi Zheng , Shakeel Butt , Kiryl Shutsemau , Jason Gunthorpe , Vlastimil Babka Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, linux-doc@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-mm@kvack.org, linux-coco@lists.linux.dev, Ackerley Tng X-Mailer: b4 0.14.3 X-Developer-Signature: v=1; a=ed25519-sha256; t=1778185365; l=3906; i=ackerleytng@google.com; s=20260225; h=from:subject:message-id; bh=xNCKakm4lqe+pmjFgVS7wo4ZhPYHCXdFbzSjFPcag4M=; b=UCt2SNnICZlnJSPZnLmK/7mEn5zP0XIxOF5nvBDiH6wNJ4ztx+HYJvK2CEx5QGGYLQYJg8mwK 4hprW9He5esBNRrL2NCxQ/In/x7MI0yA78dKT2W+HYPt+W/hGgOkwGp X-Developer-Key: i=ackerleytng@google.com; a=ed25519; pk=sAZDYXdm6Iz8FHitpHeFlCMXwabodTm7p8/3/8xUxuU= X-Endpoint-Received: by B4 Relay for ackerleytng@google.com/20260225 with auth_id=649 X-Original-From: Ackerley Tng Reply-To: ackerleytng@google.com From: Ackerley Tng Introduce a new helper, kvm_gpa_to_guest_memfd(), to find the guest_memfd-related details of a memory region that contains a given guest physical address (GPA). The function returns the file descriptor for the memfd, the offset into the file that corresponds to the GPA, and the number of bytes remaining in the region from that GPA. kvm_gpa_to_guest_memfd() was factored out from vm_guest_mem_fallocate(); refactor vm_guest_mem_fallocate() to use the new helper. Signed-off-by: Ackerley Tng Co-developed-by: Sean Christopherson Signed-off-by: Sean Christopherson --- tools/testing/selftests/kvm/include/kvm_util.h | 3 +++ tools/testing/selftests/kvm/lib/kvm_util.c | 37 ++++++++++++++++---------- 2 files changed, 26 insertions(+), 14 deletions(-) diff --git a/tools/testing/selftests/kvm/include/kvm_util.h b/tools/testing/selftests/kvm/include/kvm_util.h index f7c49739e97b4..4ad184ce3df68 100644 --- a/tools/testing/selftests/kvm/include/kvm_util.h +++ b/tools/testing/selftests/kvm/include/kvm_util.h @@ -428,6 +428,9 @@ static inline void vm_enable_cap(struct kvm_vm *vm, u32 cap, u64 arg0) vm_ioctl(vm, KVM_ENABLE_CAP, &enable_cap); } +int kvm_gpa_to_guest_memfd(struct kvm_vm *vm, gpa_t gpa, off_t *fd_offset, + size_t *nr_bytes); + /* * KVM_SET_MEMORY_ATTRIBUTES{,2} overwrites _all_ attributes. These * flows need significant enhancements to support multiple attributes. diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c index 5e34593ad79c4..8ff09e179ff5c 100644 --- a/tools/testing/selftests/kvm/lib/kvm_util.c +++ b/tools/testing/selftests/kvm/lib/kvm_util.c @@ -1283,27 +1283,20 @@ void vm_guest_mem_fallocate(struct kvm_vm *vm, u64 base, u64 size, bool punch_hole) { const int mode = FALLOC_FL_KEEP_SIZE | (punch_hole ? FALLOC_FL_PUNCH_HOLE : 0); - struct userspace_mem_region *region; u64 end = base + size; - gpa_t gpa, len; off_t fd_offset; - int ret; + int fd, ret; + size_t len; + gpa_t gpa; for (gpa = base; gpa < end; gpa += len) { - u64 offset; - - region = userspace_mem_region_find(vm, gpa, gpa); - TEST_ASSERT(region && region->region.flags & KVM_MEM_GUEST_MEMFD, - "Private memory region not found for GPA 0x%lx", gpa); + fd = kvm_gpa_to_guest_memfd(vm, gpa, &fd_offset, &len); + len = min(end - gpa, len); - offset = gpa - region->region.guest_phys_addr; - fd_offset = region->region.guest_memfd_offset + offset; - len = min_t(u64, end - gpa, region->region.memory_size - offset); - - ret = fallocate(region->region.guest_memfd, mode, fd_offset, len); + ret = fallocate(fd, mode, fd_offset, len); TEST_ASSERT(!ret, "fallocate() failed to %s at %lx (len = %lu), fd = %d, mode = %x, offset = %lx", punch_hole ? "punch hole" : "allocate", gpa, len, - region->region.guest_memfd, mode, fd_offset); + fd, mode, fd_offset); } } @@ -1640,6 +1633,22 @@ void *addr_gpa2alias(struct kvm_vm *vm, gpa_t gpa) return (void *) ((uintptr_t) region->host_alias + offset); } +int kvm_gpa_to_guest_memfd(struct kvm_vm *vm, gpa_t gpa, off_t *fd_offset, + size_t *nr_bytes) +{ + struct userspace_mem_region *region; + gpa_t gpa_offset; + + region = userspace_mem_region_find(vm, gpa, gpa); + TEST_ASSERT(region && region->region.flags & KVM_MEM_GUEST_MEMFD, + "guest_memfd memory region not found for GPA 0x%lx", gpa); + + gpa_offset = gpa - region->region.guest_phys_addr; + *fd_offset = region->region.guest_memfd_offset + gpa_offset; + *nr_bytes = region->region.memory_size - gpa_offset; + return region->region.guest_memfd; +} + /* Create an interrupt controller chip for the specified VM. */ void vm_create_irqchip(struct kvm_vm *vm) { -- 2.54.0.563.g4f69b47b94-goog