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 DA8DA357A4A; Mon, 31 Aug 2026 00:25:23 +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=1788135923; cv=none; b=XIa2kacywd1BUbyEEGm2mLLceDIz+8clZQLkhtnedwFMHpSugjSdX5BQ98Qoenmsj91Gh0cOkl1HGfMhQ+nQLLesMGLwF5yJ3aKV1ztqQq6+uwGEf5rHjz7uGooIS1/prDoIQ817Qht8ifRUIvMt/GmGhgmApKkVyhY2v0bcO50= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788135923; c=relaxed/simple; bh=tbu5H941T3WFmTkcFYkjGccJoW2TPAMlO8ekt00YDMs=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=R7UqODSwkaK/1lr+3pbiD42CQ0mZQoekKvm+NvhpKbkYWzNx/Q2ftd/Ub6UlvmsEMcepiILl8ISuuG6FqBKH1mzdHNvQXXMboKSmCjiNX0sa8FOeUb6b+j447speO/DaIgy53cHzdXiQ+nzuEHDdVewy8Ze3QSpotH4Kl9Hs+7E= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=qLdd0WYG; 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="qLdd0WYG" Received: by smtp.kernel.org (Postfix) with ESMTPS id B5432C2BCFF; Mon, 31 Aug 2026 00:25:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1788135923; bh=tbu5H941T3WFmTkcFYkjGccJoW2TPAMlO8ekt00YDMs=; h=From:Date:Subject:References:In-Reply-To:To:Cc:Reply-To:From; b=qLdd0WYG07wxjmoTmvbspYTXLe89JNFssEMi+/rkuZGYIRdzdKg7RubQxPC5eEDUl xWPTTAwNH4hVWxT3FqNU/Vbec3rXeaie2lyXwjrK+h4G9GHlzAc5jCWlFMnGfzYFP0 xRBQZUgqZqIdMbazPBh5dLiCtF3oFuLW1uPBIX7DgzhRL0FGgCACrjgUBx+J1jrhJU A5dwzkyx6yZuROIt8d5vl2jcvZdQ0M3L3hgfECB+WmB+Iq6k7EUx2kh2men14JXQEu Ejed8kqKvgMVxdfNM3soweAU5SAeUNYmfa5/nhl0TN563MUzz87i6EEZf477JX/bMa c+KgOuJdDlLtQ== 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 9B894C624C2; Mon, 31 Aug 2026 00:25:23 +0000 (UTC) From: Ackerley Tng via B4 Relay Date: Sun, 30 Aug 2026 17:25:41 -0700 Subject: [PATCH v12 40/45] 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: <20260830-gmem-inplace-conversion-v12-40-85e5fd25252a@google.com> References: <20260830-gmem-inplace-conversion-v12-0-85e5fd25252a@google.com> In-Reply-To: <20260830-gmem-inplace-conversion-v12-0-85e5fd25252a@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, 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, 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 , Barry Song , Axel Rasmussen , Yuanchu Xie , Wei Xu , Youngjun Park , Qi Zheng , Shakeel Butt , Kiryl Shutsemau , Baoquan He , Jason Gunthorpe , John Hubbard , Peter Xu , tarunsahu@google.com, Randy Dunlap , Lorenzo Stoakes , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Jason Gunthorpe , Fuad Tabba , Vlastimil Babka , Baoquan He 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=1788135916; l=3994; i=ackerleytng@google.com; s=20260225; h=from:subject:message-id; bh=aODtj3bXiyKjP4uoEZrBjbprOQXjj5kFxo+MyuHmpxU=; b=814LT748FADHWK7t5YnPGMVd2fhYxt4cbFtAGUXwoXEic+bZE3wurSvaMhHeph8EyNcGn/JJt Y4jxXfT+FFPDaK7q3wrjhxRlMZ2eNvl2G3nr6Qflsl9ATYEbd1JM9x1 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. Co-developed-by: Sean Christopherson Signed-off-by: Sean Christopherson Reviewed-by: Fuad Tabba Tested-by: Shivank Garg Signed-off-by: Ackerley Tng --- 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 3cfe243d7c8b0..795c9eb311071 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 b1456ed76e27e..1188d0a6c0a5f 100644 --- a/tools/testing/selftests/kvm/lib/kvm_util.c +++ b/tools/testing/selftests/kvm/lib/kvm_util.c @@ -1332,27 +1332,20 @@ 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); } } @@ -1689,6 +1682,22 @@ 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) { -- 2.55.0.897.gb25b4bd76c-goog