From patchwork Mon Jul 6 13:26:26 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Philippe_Mathieu-Daud=C3=A9?= X-Patchwork-Id: 11645769 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id B8A6513B4 for ; Mon, 6 Jul 2020 13:28:33 +0000 (UTC) Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 9172120702 for ; Mon, 6 Jul 2020 13:28:33 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="PlGM7K2N" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9172120702 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=amsat.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=xen-devel-bounces@lists.xenproject.org Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1jsR8r-00037l-65; Mon, 06 Jul 2020 13:26:41 +0000 Received: from us1-rack-iad1.inumbo.com ([172.99.69.81]) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1jsR8q-00036i-5w for xen-devel@lists.xenproject.org; Mon, 06 Jul 2020 13:26:40 +0000 X-Inumbo-ID: 4ec70d86-bf8c-11ea-bb8b-bc764e2007e4 Received: from mail-wm1-x344.google.com (unknown [2a00:1450:4864:20::344]) by us1-rack-iad1.inumbo.com (Halon) with ESMTPS id 4ec70d86-bf8c-11ea-bb8b-bc764e2007e4; Mon, 06 Jul 2020 13:26:33 +0000 (UTC) Received: by mail-wm1-x344.google.com with SMTP id j18so39340130wmi.3 for ; Mon, 06 Jul 2020 06:26:33 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=am5VN7/n2uE761M3Be1VEooh2n0rBobtAPOGmP3qI4M=; b=PlGM7K2N9i/6GjPrNncv7DxyXCLNbt7NBGOom7aipSBKKp5prlHJhp+HFPsFuT4+is xseCSUB/jgvFhr3ULyxOwZdS9u0bk3Wwu9+YTHByX2wlHB71sQivtYCnoRIvFt2KY3uf fN4I4vvRh1d8nRqWcB8UklaPnOBI/51LHmUjaSDGrHwDIlgzALaxwhtH31OD6oSKnhZD r0Xi5YaZiwHwhZTwvQu2XwsVQ7cjbKYhMwVJrzc9WJii2XY3MFJNKMfCBYF/noAuJjgo T8mULoejBWDQVOgUE6fIPARLJ+vYQMu6ou6bP2zwbFHxoiRiXgo3x3KzgTiRV19hr3QV 3Mmw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:from:to:cc:subject:date:message-id :in-reply-to:references:mime-version:content-transfer-encoding; bh=am5VN7/n2uE761M3Be1VEooh2n0rBobtAPOGmP3qI4M=; b=szhSuiOwhImdXWjpaKugBgwse1x9GMYGEk4ZOrEiFyZUN7xpdSlbI+wUEyzMqSyFjD aVmLNDXDE99vIA0F7BEnprqzKBJ5em77XOGwZ1Ef9FcdbqzLp6cwg4pwKOSx0ddrVUP5 6YiExWQKS9qzuAmlhqMffotK1iTtUi4Ns1v5LHcBgw2/KHGCgvxoG53h3l+PdXn0xtB/ b5aLWq28NmWNIUTlegH9IN35VnnuDLR8l9qxJB/PKLDse6ZU1Du8tns/IariHXYl0Qg8 2K7j/OQDIbt4NuVe1NC+2boRtAFnPtjDL9eLX4naRj3lFmQrUaSQpB1M+GmF7hMYQVM5 Li6A== X-Gm-Message-State: AOAM532iwGo515bzDCPkRdXZhyAN6vJBX4JBLRp/TVs6YE5kDfc+FCuR tRocxKTF8m5ef61xSNfif5A= X-Google-Smtp-Source: ABdhPJx9IhLPFnhwHRB01b+AXuniNDNUxthdSjEywHNwuq58/NRF/JoFZuUsEzKmhlDAFVaeOqBIOw== X-Received: by 2002:a7b:c0c9:: with SMTP id s9mr46471167wmh.166.1594041992205; Mon, 06 Jul 2020 06:26:32 -0700 (PDT) Received: from localhost.localdomain (138.red-83-57-170.dynamicip.rima-tde.net. [83.57.170.138]) by smtp.gmail.com with ESMTPSA id w2sm24447004wrs.77.2020.07.06.06.26.30 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 06 Jul 2020 06:26:31 -0700 (PDT) From: =?utf-8?q?Philippe_Mathieu-Daud=C3=A9?= To: Markus Armbruster , qemu-devel@nongnu.org Subject: [RFC PATCH 2/2] block/block-backend: Let blk_attach_dev() provide helpful error Date: Mon, 6 Jul 2020 15:26:26 +0200 Message-Id: <20200706132626.22133-3-f4bug@amsat.org> X-Mailer: git-send-email 2.21.3 In-Reply-To: <20200706132626.22133-1-f4bug@amsat.org> References: <20200706132626.22133-1-f4bug@amsat.org> MIME-Version: 1.0 X-BeenThere: xen-devel@lists.xenproject.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Cc: Fam Zheng , Kevin Wolf , Stefano Stabellini , =?utf-8?q?Daniel_P=2E_Berrang?= =?utf-8?q?=C3=A9?= , Eduardo Habkost , qemu-block@nongnu.org, Paul Durrant , Laurent Vivier , Max Reitz , Paolo Bonzini , Anthony Perard , xen-devel@lists.xenproject.org, John Snow , =?utf-8?q?Philippe_Mathieu-Daud=C3=A9?= Errors-To: xen-devel-bounces@lists.xenproject.org Sender: "Xen-devel" Let blk_attach_dev() take an Error* object to return helpful information. Adapt the callers. $ qemu-system-arm -M n800 qemu-system-arm: sd_init failed: cannot attach blk 'sd0' to device 'sd-card' because it is already attached by device 'omap2-mmc' Drive 'sd0' is already in use because it has been automatically connected to another device (did you need 'if=none' in the drive options?) Signed-off-by: Philippe Mathieu-Daudé --- RFC: I'm not sure the error API is correctly used in set_drive_helper(). include/sysemu/block-backend.h | 2 +- block/block-backend.c | 11 ++++++++++- hw/block/fdc.c | 4 +--- hw/block/swim.c | 4 +--- hw/block/xen-block.c | 5 +++-- hw/core/qdev-properties-system.c | 17 ++++++++++------- hw/ide/qdev.c | 4 +--- hw/scsi/scsi-disk.c | 4 +--- 8 files changed, 28 insertions(+), 23 deletions(-) diff --git a/include/sysemu/block-backend.h b/include/sysemu/block-backend.h index 8203d7f6f9..118fbad0b4 100644 --- a/include/sysemu/block-backend.h +++ b/include/sysemu/block-backend.h @@ -113,7 +113,7 @@ BlockDeviceIoStatus blk_iostatus(const BlockBackend *blk); void blk_iostatus_disable(BlockBackend *blk); void blk_iostatus_reset(BlockBackend *blk); void blk_iostatus_set_err(BlockBackend *blk, int error); -int blk_attach_dev(BlockBackend *blk, DeviceState *dev); +int blk_attach_dev(BlockBackend *blk, DeviceState *dev, Error **errp); void blk_detach_dev(BlockBackend *blk, DeviceState *dev); DeviceState *blk_get_attached_dev(BlockBackend *blk); char *blk_get_attached_dev_id(BlockBackend *blk); diff --git a/block/block-backend.c b/block/block-backend.c index 23caa45e6a..29480a121d 100644 --- a/block/block-backend.c +++ b/block/block-backend.c @@ -882,12 +882,21 @@ void blk_get_perm(BlockBackend *blk, uint64_t *perm, uint64_t *shared_perm) /* * Attach device model @dev to @blk. + * + * @blk: Block backend + * @dev: Device to attach the block backend to + * @errp: pointer to NULL initialized error object + * * Return 0 on success, -EBUSY when a device model is attached already. */ -int blk_attach_dev(BlockBackend *blk, DeviceState *dev) +int blk_attach_dev(BlockBackend *blk, DeviceState *dev, Error **errp) { trace_blk_attach_dev(blk_name(blk), object_get_typename(OBJECT(dev))); if (blk->dev) { + error_setg(errp, "cannot attach blk '%s' to device '%s' because it is " + "already attached by device '%s'", + blk_name(blk), object_get_typename(OBJECT(dev)), + object_get_typename(OBJECT(blk->dev))); return -EBUSY; } diff --git a/hw/block/fdc.c b/hw/block/fdc.c index 3425d56e2a..5765b5d4f2 100644 --- a/hw/block/fdc.c +++ b/hw/block/fdc.c @@ -519,7 +519,6 @@ static void floppy_drive_realize(DeviceState *qdev, Error **errp) FloppyBus *bus = FLOPPY_BUS(qdev->parent_bus); FDrive *drive; bool read_only; - int ret; if (dev->unit == -1) { for (dev->unit = 0; dev->unit < MAX_FD; dev->unit++) { @@ -545,8 +544,7 @@ static void floppy_drive_realize(DeviceState *qdev, Error **errp) if (!dev->conf.blk) { /* Anonymous BlockBackend for an empty drive */ dev->conf.blk = blk_new(qemu_get_aio_context(), 0, BLK_PERM_ALL); - ret = blk_attach_dev(dev->conf.blk, qdev); - assert(ret == 0); + blk_attach_dev(dev->conf.blk, qdev, &error_abort); /* Don't take write permissions on an empty drive to allow attaching a * read-only node later */ diff --git a/hw/block/swim.c b/hw/block/swim.c index 74f56e8f46..2f1ecd0bb2 100644 --- a/hw/block/swim.c +++ b/hw/block/swim.c @@ -159,7 +159,6 @@ static void swim_drive_realize(DeviceState *qdev, Error **errp) SWIMDrive *dev = SWIM_DRIVE(qdev); SWIMBus *bus = SWIM_BUS(qdev->parent_bus); FDrive *drive; - int ret; if (dev->unit == -1) { for (dev->unit = 0; dev->unit < SWIM_MAX_FD; dev->unit++) { @@ -185,8 +184,7 @@ static void swim_drive_realize(DeviceState *qdev, Error **errp) if (!dev->conf.blk) { /* Anonymous BlockBackend for an empty drive */ dev->conf.blk = blk_new(qemu_get_aio_context(), 0, BLK_PERM_ALL); - ret = blk_attach_dev(dev->conf.blk, qdev); - assert(ret == 0); + blk_attach_dev(dev->conf.blk, qdev, &error_abort); } if (!blkconf_blocksizes(&dev->conf, errp)) { diff --git a/hw/block/xen-block.c b/hw/block/xen-block.c index 1b7bc5de08..81650208dc 100644 --- a/hw/block/xen-block.c +++ b/hw/block/xen-block.c @@ -616,14 +616,15 @@ static void xen_cdrom_realize(XenBlockDevice *blockdev, Error **errp) blockdev->device_type = "cdrom"; if (!conf->blk) { + Error *local_err = NULL; int rc; /* Set up an empty drive */ conf->blk = blk_new(qemu_get_aio_context(), 0, BLK_PERM_ALL); - rc = blk_attach_dev(conf->blk, DEVICE(blockdev)); + rc = blk_attach_dev(conf->blk, DEVICE(blockdev), &local_err); if (!rc) { - error_setg_errno(errp, -rc, "failed to create drive"); + error_propagate_prepend(errp, local_err, "failed to create drive"); return; } } diff --git a/hw/core/qdev-properties-system.c b/hw/core/qdev-properties-system.c index 38b0c9f09b..26dc9f1779 100644 --- a/hw/core/qdev-properties-system.c +++ b/hw/core/qdev-properties-system.c @@ -139,18 +139,21 @@ static void set_drive_helper(Object *obj, Visitor *v, const char *name, object_get_typename(OBJECT(dev)), prop->name, str); goto fail; } - if (blk_attach_dev(blk, dev) < 0) { + if (blk_attach_dev(blk, dev, &local_err) < 0) { DriveInfo *dinfo = blk_legacy_dinfo(blk); if (dinfo && dinfo->type != IF_NONE) { - error_setg(errp, "Drive '%s' is already in use because " - "it has been automatically connected to another " - "device (did you need 'if=none' in the drive options?)", - str); + error_append_hint(&local_err, + "Drive '%s' is already in use because it has " + "been automatically connected to another device " + "(did you need 'if=none' in the drive options?)" + "\n", str); } else { - error_setg(errp, "Drive '%s' is already in use by another device", - str); + error_append_hint(&local_err, + "Drive '%s' is already in use by another device", + str); } + error_propagate(errp, local_err); goto fail; } diff --git a/hw/ide/qdev.c b/hw/ide/qdev.c index f68fbee93d..b36499c9ee 100644 --- a/hw/ide/qdev.c +++ b/hw/ide/qdev.c @@ -165,7 +165,6 @@ static void ide_dev_initfn(IDEDevice *dev, IDEDriveKind kind, Error **errp) { IDEBus *bus = DO_UPCAST(IDEBus, qbus, dev->qdev.parent_bus); IDEState *s = bus->ifs + dev->unit; - int ret; if (!dev->conf.blk) { if (kind != IDE_CD) { @@ -174,8 +173,7 @@ static void ide_dev_initfn(IDEDevice *dev, IDEDriveKind kind, Error **errp) } else { /* Anonymous BlockBackend for an empty drive */ dev->conf.blk = blk_new(qemu_get_aio_context(), 0, BLK_PERM_ALL); - ret = blk_attach_dev(dev->conf.blk, &dev->qdev); - assert(ret == 0); + blk_attach_dev(dev->conf.blk, &dev->qdev, &error_abort); } } diff --git a/hw/scsi/scsi-disk.c b/hw/scsi/scsi-disk.c index 8ce68a9dd6..92350642c7 100644 --- a/hw/scsi/scsi-disk.c +++ b/hw/scsi/scsi-disk.c @@ -2451,14 +2451,12 @@ static void scsi_cd_realize(SCSIDevice *dev, Error **errp) { SCSIDiskState *s = DO_UPCAST(SCSIDiskState, qdev, dev); AioContext *ctx; - int ret; if (!dev->conf.blk) { /* Anonymous BlockBackend for an empty drive. As we put it into * dev->conf, qdev takes care of detaching on unplug. */ dev->conf.blk = blk_new(qemu_get_aio_context(), 0, BLK_PERM_ALL); - ret = blk_attach_dev(dev->conf.blk, &dev->qdev); - assert(ret == 0); + blk_attach_dev(dev->conf.blk, &dev->qdev, &error_abort); } ctx = blk_get_aio_context(dev->conf.blk);