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 2D31A3D566D; Tue, 28 Apr 2026 23:25:21 +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=1777418721; cv=none; b=X+caBavdoBO9Lh6PoLWKAl47tuDDPvbZ0JNKsvKYVU29YhX754YEedOCGVw642Gy8DCszopJ5P60LJHp8w72sTRqGSBkEVVdJMLfPpzW/KMyG1+qQSiHjudachT0WQZmhI+6GHL2V/iMUzi+1oW1Zb4O1SUe3yo4Vjf5qNK7rSM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777418721; c=relaxed/simple; bh=mwkgk7A8hFc2PxDEeFm6pEnfqmPWkj5TqPujEB8TS+w=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=rjzWPcDimGquQOfZQRExnfazXdqwA/KflBsdJGYZrPa56Br/P3QoKD8GE446bKdpgw3cjkRJxByXUQqptMBgai1vA0I7zMpQuODiPx4yHytF1qffQ/VoDS+aH2tvn/gb6D+J6t6QhCz+q+xdmRqrumW7d1Ctqwt1bCGnpmNNIh4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Rp401V6E; 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="Rp401V6E" Received: by smtp.kernel.org (Postfix) with ESMTPS id 10E47C2BCC9; Tue, 28 Apr 2026 23:25:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1777418721; bh=mwkgk7A8hFc2PxDEeFm6pEnfqmPWkj5TqPujEB8TS+w=; h=From:Date:Subject:References:In-Reply-To:To:Cc:Reply-To:From; b=Rp401V6ECX1gEsLEV0pf4PelPwAttxOwivufPzzsFK8aTbzDeJ9a6Ak/BWLzVv9Ax M2SbzjBE6/+Q3tz6O7UJEhputyg261KcRHxp6J2LFGYIXNg35pTo+Q4IATJNrSk7Wd tVMCESXsE0P6tZQWNpba/YRrlPnOu+4D+J4TF04k0nnxvZr3K0ryvTsCxLFx1A7UlF xa7pxZ/W94Iztd6sNrmUhPjcW6gHXjeelgo0gKZJWCCqS0D1AlM7Ggt56J6b5xafmm KDVOc/SlT7c2EXDB3SNaKZOnTTxlMj3tExcjxTWpwpiH15g+jKzMl8b6gtybuKbLYx Tv+4jjYPfb3Jw== 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 0740BFF887E; Tue, 28 Apr 2026 23:25:21 +0000 (UTC) From: Ackerley Tng via B4 Relay Date: Tue, 28 Apr 2026 16:25:41 -0700 Subject: [PATCH RFC v5 46/53] KVM: selftests: Provide function to look up guest_memfd details from gpa Precedence: bulk X-Mailing-List: linux-trace-kernel@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: <20260428-gmem-inplace-conversion-v5-46-d8608ccfca22@google.com> References: <20260428-gmem-inplace-conversion-v5-0-d8608ccfca22@google.com> In-Reply-To: <20260428-gmem-inplace-conversion-v5-0-d8608ccfca22@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, 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=1777418714; l=3877; i=ackerleytng@google.com; s=20260225; h=from:subject:message-id; bh=Xc+MUzeFyBLqIxQeeove1J/69O/NRCP9DFI9k+NHIr0=; b=W1wuVqqKA/T+YKlV9bCqGjI4UHZ9nsom3khaNv6fjoqr4kJjIUCGS7SXpK1EaP4DvoNqg9660 JNsOz0AnsxQDhxWPEMKtEImjgwdIt1LCW9dYvUMi4MOuu95MmbCZLK2 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 | 34 ++++++++++++++++---------- 2 files changed, 24 insertions(+), 13 deletions(-) diff --git a/tools/testing/selftests/kvm/include/kvm_util.h b/tools/testing/selftests/kvm/include/kvm_util.h index 62d917a2d2b19..7de88cbdfd2b8 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..12e031a8fc20d 100644 --- a/tools/testing/selftests/kvm/lib/kvm_util.c +++ b/tools/testing/selftests/kvm/lib/kvm_util.c @@ -1283,27 +1283,19 @@ 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; 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 +1632,22 @@ 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) { -- 2.54.0.545.g6539524ca2-goog