From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f201.google.com (mail-pl1-f201.google.com [209.85.214.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 16F9738E10D for ; Mon, 2 Feb 2026 22:31:11 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770071474; cv=none; b=oG+EDN6IxGDuXyWKOlcTvHWRZdbcSkDupOMKXHb3Zjs+mgqYaF+8gfBRdnKW/f5WTh/NiVaeeij+LhH6sDKRBuzBP/PoKhaX+QHn+oLhetqHxuzItuB3cMd3h59zsgAWEDNfyQz/5aWt0lFh94LaZShyBjtNHfDcojUP5Q5r/98= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770071474; c=relaxed/simple; bh=rhPa7e2nbHKPgcSIpSn/eTrXn9i9fhs462e3RBGjlu0=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=JHbHOIc+WJumKVaWqlteQkvtA4/C3kt5OKW+ukFzYXhEhLdNxqKMsAAKmx1wKQCaKTJn0PuoYrsRnk+vkD3LtuzeLKocL2h4kJBRcKGCCSpkH/MgH3JVjVNATACIMcCrBUuiNpYuDFdEOzg1MbTdgP7y33QayzGvvDQAzS8NA10= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--ackerleytng.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=WZlkgRE2; arc=none smtp.client-ip=209.85.214.201 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--ackerleytng.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="WZlkgRE2" Received: by mail-pl1-f201.google.com with SMTP id d9443c01a7336-2a784b2234dso137638515ad.1 for ; Mon, 02 Feb 2026 14:31:11 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1770071471; x=1770676271; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=+LasQi9MZpEXca97c2GcW0Xzf1pgBMgUd5URnFGTxTw=; b=WZlkgRE2RoL0usg+N0Dw6kSr0bsUsZF66bu/tmlIXch61TL0vpMH6l3jUkD3om6XeY falyvd9BwE3ihvPt6JeunSiFVSdxbu2hxJEHfFo96ZnvUlut2UjcSgqFZCA42eWt5Qrc Qh/DVrMMf2MobIcQxMJDa1O7EaVtXDnYB70Ac3cr0xQnLrDDkjyOa/m1Dw0ao3lxy/0k KN3h1cNqvLqT2EylIXSAlppNkWJUBPOxikvK6HVF2UGFn1k90R2AstiewidRb61A4RIK 94oesHS+Q8yCA6x+B+wpWQ/WYWATkurZljY6H0gz6j4n8ikzZYSp6HUFUkzh6cxIFNI5 Fb3A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1770071471; x=1770676271; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=+LasQi9MZpEXca97c2GcW0Xzf1pgBMgUd5URnFGTxTw=; b=Ue0gZwmTzkVVoQ1iXInAJiVrY4sAT/4aiX9pR8yZD7QuxWqiW7x8YSiycEM3vsZneN WP//qklQnJ5UI9+OFQtocSnv14+/YAYacUWzTtdRj6gWy4b3/ZAmu1gevXYZdcJm/l2P 3KDUtmCTKgkxmOPByXPxjNVavDOz2bTZ6RUT++3+tE987RaPl7OHNC91PHI0B7MdlLlh 0mIDf0c+kQg0b/u2+4aBhg0s3KdZBO+rHFpZJZQgd87UZcUQf5qe1ELQVf87YQCwcf/V GNvhsVyWLHMon0UH216M4sHFEv0FR9t6GQmkO7PZuRRhja5ROsiwp/CQcWVsEhllbN0l UyCg== X-Forwarded-Encrypted: i=1; AJvYcCUNPfww1s/TYzt4NpBFHTHQhbDQgfgLJ3/pyjC8XuqNL9D7+7SQ/d4MzKCp723Kyjcm2C5bCOCJffkDyEJcX9qPmu0=@vger.kernel.org X-Gm-Message-State: AOJu0YwY/eJihEqdwvH9RUBdhFnoN54ANtZITb9sr9Is93czmXMgX5A4 t4y00M3QsmnRvNZXQ7K3SINPJdoIN7A2omWIP1jFMvL8rG5K1db4q7Rb1R26VyR4pE5x0yQcLDY 8NtiTDhf9ePsFAi2xCFRtt/gzkA== X-Received: from pltg6.prod.google.com ([2002:a17:902:6b46:b0:29f:101f:a1d7]) (user=ackerleytng job=prod-delivery.src-stubby-dispatcher) by 2002:a17:903:2389:b0:29e:e925:1abb with SMTP id d9443c01a7336-2a8d96e3de3mr134547405ad.27.1770071471269; Mon, 02 Feb 2026 14:31:11 -0800 (PST) Date: Mon, 2 Feb 2026 14:30:08 -0800 In-Reply-To: Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: X-Mailer: git-send-email 2.53.0.rc1.225.gd81095ad13-goog Message-ID: <106c16f75862ed98989f1ae8ebaa06ecbc4a39d9.1770071243.git.ackerleytng@google.com> Subject: [RFC PATCH v2 30/37] KVM: selftests: Provide function to look up guest_memfd details from gpa From: Ackerley Tng To: kvm@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-trace-kernel@vger.kernel.org, x86@kernel.org Cc: aik@amd.com, andrew.jones@linux.dev, binbin.wu@linux.intel.com, bp@alien8.de, brauner@kernel.org, chao.p.peng@intel.com, chao.p.peng@linux.intel.com, chenhuacai@kernel.org, corbet@lwn.net, dave.hansen@linux.intel.com, david@kernel.org, hpa@zytor.com, ira.weiny@intel.com, jgg@nvidia.com, jmattson@google.com, jroedel@suse.de, jthoughton@google.com, maobibo@loongson.cn, mathieu.desnoyers@efficios.com, maz@kernel.org, mhiramat@kernel.org, michael.roth@amd.com, mingo@redhat.com, mlevitsk@redhat.com, oupton@kernel.org, pankaj.gupta@amd.com, pbonzini@redhat.com, prsampat@amd.com, qperret@google.com, ricarkol@google.com, rick.p.edgecombe@intel.com, rientjes@google.com, rostedt@goodmis.org, seanjc@google.com, shivankg@amd.com, shuah@kernel.org, steven.price@arm.com, tabba@google.com, tglx@linutronix.de, vannapurve@google.com, vbabka@suse.cz, willy@infradead.org, wyihan@google.com, yan.y.zhao@intel.com, Ackerley Tng Content-Type: text/plain; charset="UTF-8" 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 --- .../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 e767f9a99a7b..b370b70442e8 100644 --- a/tools/testing/selftests/kvm/include/kvm_util.h +++ b/tools/testing/selftests/kvm/include/kvm_util.h @@ -404,6 +404,9 @@ static inline void vm_enable_cap(struct kvm_vm *vm, uint32_t cap, uint64_t arg0) vm_ioctl(vm, KVM_ENABLE_CAP, &enable_cap); } +int kvm_gpa_to_guest_memfd(struct kvm_vm *vm, vm_paddr_t gpa, off_t *fd_offset, + uint64_t *nr_bytes); + /* * KVM_SET_MEMORY_ATTRIBUTES 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 4f464ad8dffd..61adfd7e623c 100644 --- a/tools/testing/selftests/kvm/lib/kvm_util.c +++ b/tools/testing/selftests/kvm/lib/kvm_util.c @@ -1258,27 +1258,19 @@ void vm_guest_mem_fallocate(struct kvm_vm *vm, uint64_t base, uint64_t size, bool punch_hole) { const int mode = FALLOC_FL_KEEP_SIZE | (punch_hole ? FALLOC_FL_PUNCH_HOLE : 0); - struct userspace_mem_region *region; uint64_t end = base + size; uint64_t gpa, len; off_t fd_offset; - int ret; + int fd, ret; for (gpa = base; gpa < end; gpa += len) { - uint64_t 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(uint64_t, 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); } } @@ -1684,6 +1676,22 @@ void *addr_gpa2alias(struct kvm_vm *vm, vm_paddr_t gpa) return (void *) ((uintptr_t) region->host_alias + offset); } +int kvm_gpa_to_guest_memfd(struct kvm_vm *vm, vm_paddr_t gpa, off_t *fd_offset, + uint64_t *nr_bytes) +{ + struct userspace_mem_region *region; + vm_paddr_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) { -- 2.53.0.rc1.225.gd81095ad13-goog