From patchwork Tue Feb 11 21:43:28 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kevin Wolf X-Patchwork-Id: 13970755 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 30118C0219B for ; Tue, 11 Feb 2025 21:48:37 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1thy6N-0002jT-I2; Tue, 11 Feb 2025 16:47:31 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1thy3k-00089E-Fe for qemu-devel@nongnu.org; Tue, 11 Feb 2025 16:44:48 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1thy3g-0005aB-WB for qemu-devel@nongnu.org; Tue, 11 Feb 2025 16:44:47 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1739310282; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=EQGiwTCHjvG0hJog8XC9+JXJepkNrNsdabgIXvuqv1g=; b=PvLOIBdLWjoDHdM5okSlkNVlwZW05oHMRXaTZf4ihkzul+hpizJoZlayIPcW3ZW0KozDN9 qG570BBZDl77ccCm/ocOv5GDgfBPVFbQ9XAA42W1ujZNlk7FKsswNoyoh4mYH3EVOcjBRl CZPKsjE7YacJSmlOnX2ZiTB1QqyqJv8= Received: from mx-prod-mc-05.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-591-vZ7AGSsxMHCCLTBQoS_rVw-1; Tue, 11 Feb 2025 16:44:39 -0500 X-MC-Unique: vZ7AGSsxMHCCLTBQoS_rVw-1 X-Mimecast-MFC-AGG-ID: vZ7AGSsxMHCCLTBQoS_rVw Received: from mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.17]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 5A80A19560A7; Tue, 11 Feb 2025 21:44:38 +0000 (UTC) Received: from merkur.redhat.com (unknown [10.44.32.210]) by mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 0B89E195608D; Tue, 11 Feb 2025 21:44:35 +0000 (UTC) From: Kevin Wolf To: qemu-block@nongnu.org Cc: kwolf@redhat.com, hreitz@redhat.com, pbonzini@redhat.com, manos.pitsidianakis@linaro.org, qemu-devel@nongnu.org, qemu-rust@nongnu.org Subject: [PATCH 11/11] rust/block: Add format probing Date: Tue, 11 Feb 2025 22:43:28 +0100 Message-ID: <20250211214328.640374-12-kwolf@redhat.com> In-Reply-To: <20250211214328.640374-1-kwolf@redhat.com> References: <20250211214328.640374-1-kwolf@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.0 on 10.30.177.17 Received-SPF: pass client-ip=170.10.129.124; envelope-from=kwolf@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -35 X-Spam_score: -3.6 X-Spam_bar: --- X-Spam_report: (-3.6 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-1.54, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H5=0.001, RCVD_IN_MSPIKE_WL=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, RCVD_IN_VALIDITY_SAFE_BLOCKED=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=unavailable autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org This adds format probing both to the BlockDriver trait and the bochs-rs block driver. With this, bochs-rs achieves feature parity with its C counterpart. Its probe function returns a higher priority so that it is preferred when both drivers are available. Signed-off-by: Kevin Wolf --- rust/block/src/bochs.rs | 20 ++++++++++++++++++++ rust/block/src/driver.rs | 26 +++++++++++++++++++++++++- 2 files changed, 45 insertions(+), 1 deletion(-) diff --git a/rust/block/src/bochs.rs b/rust/block/src/bochs.rs index 388ac5ef03..bccc55ead9 100644 --- a/rust/block/src/bochs.rs +++ b/rust/block/src/bochs.rs @@ -186,6 +186,26 @@ pub async fn new(file: BdrvChild) -> io::Result { impl BlockDriver for BochsImage { type Options = bindings::BlockdevOptionsGenericFormat; + fn probe(buf: &[u8], _filename: &str) -> u16 { + let header = match BochsHeader::from_byte_slice(buf) { + Some(header) => header, + None => return 0, + }; + + if header.magic != HEADER_MAGIC + || header.imgtype != HEADER_TYPE_REDOLOG + || header.subtype != HEADER_SUBTYPE_GROWING + { + return 0; + } + + // This driver is better than the C one which returns 100, give it priority + match header.version { + HEADER_VERSION | HEADER_V1 => 200, + _ => 0, + } + } + unsafe fn parse_options( v: &mut bindings::Visitor, opts: &mut *mut Self::Options, diff --git a/rust/block/src/driver.rs b/rust/block/src/driver.rs index 740e9266aa..727d13b751 100644 --- a/rust/block/src/driver.rs +++ b/rust/block/src/driver.rs @@ -6,7 +6,7 @@ use qemu_api::bindings; use qemu_api::futures::qemu_co_run_future; use std::cmp::min; -use std::ffi::c_void; +use std::ffi::{c_void, CStr}; use std::io::{self, Error, ErrorKind}; use std::mem::MaybeUninit; use std::ptr; @@ -65,6 +65,16 @@ unsafe fn open( errp: *mut *mut bindings::Error, ) -> std::os::raw::c_int; + /// Returns the image format probing priority of this block driver for disk images starting + /// with the byte sequence in `buf`. Probing selects the driver that returns the highest + /// number. + /// + /// If the driver doesn't support images starting with `buf`, 0 is returned. + fn probe(buf: &[u8], filename: &str) -> u16 { + let _ = (buf, filename); + 0 + } + /// Returns the size of the image in bytes fn size(&self) -> u64; @@ -156,6 +166,19 @@ pub async fn read_uninit( } } +#[doc(hidden)] +pub unsafe extern "C" fn bdrv_probe( + buf: *const u8, + buf_size: std::os::raw::c_int, + filename: *const std::os::raw::c_char, +) -> std::os::raw::c_int { + let buf = unsafe { std::slice::from_raw_parts(buf, buf_size as usize) }; + match unsafe { CStr::from_ptr(filename) }.to_str() { + Ok(filename) => D::probe(buf, filename).into(), + Err(_) => 0, + } +} + #[doc(hidden)] pub unsafe extern "C" fn bdrv_open( bs: *mut bindings::BlockDriverState, @@ -266,6 +289,7 @@ macro_rules! block_driver { ::qemu_api::bindings::BlockDriver { format_name: ::qemu_api::c_str!($fmtname).as_ptr(), instance_size: ::std::mem::size_of::<$typ>() as i32, + bdrv_probe: Some($crate::driver::bdrv_probe::<$typ>), bdrv_open: Some($crate::driver::bdrv_open::<$typ>), bdrv_close: Some($crate::driver::bdrv_close::<$typ>), bdrv_co_preadv_part: Some($crate::driver::bdrv_co_preadv_part::<$typ>),