From patchwork Thu Apr 5 15:51:51 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kevin Wolf X-Patchwork-Id: 151210 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id 2B316B7085 for ; Sat, 7 Apr 2012 02:34:53 +1000 (EST) Received: from localhost ([::1]:33335 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1SFpP3-00051k-SB for incoming@patchwork.ozlabs.org; Thu, 05 Apr 2012 12:19:17 -0400 Received: from eggs.gnu.org ([208.118.235.92]:49955) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1SFpOw-00051e-VO for qemu-devel@nongnu.org; Thu, 05 Apr 2012 12:19:12 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1SFpOu-0005du-TO for qemu-devel@nongnu.org; Thu, 05 Apr 2012 12:19:10 -0400 Received: from mx1.redhat.com ([209.132.183.28]:58560) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1SFpOu-0005db-LM for qemu-devel@nongnu.org; Thu, 05 Apr 2012 12:19:08 -0400 Received: from int-mx11.intmail.prod.int.phx2.redhat.com (int-mx11.intmail.prod.int.phx2.redhat.com [10.5.11.24]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id q35Fn4rT021571 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Thu, 5 Apr 2012 11:49:04 -0400 Received: from dhcp-5-188.str.redhat.com (vpn1-4-41.ams2.redhat.com [10.36.4.41]) by int-mx11.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id q35FmiHR007630; Thu, 5 Apr 2012 11:49:03 -0400 From: Kevin Wolf To: anthony@codemonkey.ws Date: Thu, 5 Apr 2012 17:51:51 +0200 Message-Id: <1333641144-13612-14-git-send-email-kwolf@redhat.com> In-Reply-To: <1333641144-13612-1-git-send-email-kwolf@redhat.com> References: <1333641144-13612-1-git-send-email-kwolf@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.24 X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 209.132.183.28 Cc: kwolf@redhat.com, qemu-devel@nongnu.org Subject: [Qemu-devel] [PATCH 13/46] qdev: add blocksize property type X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org From: Stefan Hajnoczi Storage interfaces like virtio-blk can be configured with block size information so that the guest can take advantage of efficient I/O request sizes. According to the SCSI Block Commands (SBC) standard a device's block size is "almost always greater than one byte and may be a multiple of 512 bytes". QEMU currently has a 512 byte minimum block size because the block layer functions work at that granularity. Furthermore, the block size should be a power of 2 because QEMU calculates bitmasks from the value. Introduce a "blocksize" property type so devices can enforce these constraints on block size values. If the constraints are relaxed in the future then this property can be updated. Introduce the new PropertyValueNotPowerOf2 QError so QMP clients know exactly why a block size value was rejected. Signed-off-by: Stefan Hajnoczi Reviewed-by: Paolo Bonzini Signed-off-by: Kevin Wolf --- hw/qdev-properties.c | 46 ++++++++++++++++++++++++++++++++++++++++++++++ hw/qdev.h | 3 +++ qerror.c | 5 +++++ qerror.h | 4 ++++ 4 files changed, 58 insertions(+), 0 deletions(-) diff --git a/hw/qdev-properties.c b/hw/qdev-properties.c index bff9152..98dd06a 100644 --- a/hw/qdev-properties.c +++ b/hw/qdev-properties.c @@ -877,6 +877,52 @@ PropertyInfo qdev_prop_pci_devfn = { .max = 0xFFFFFFFFULL, }; +/* --- blocksize --- */ + +static void set_blocksize(Object *obj, Visitor *v, void *opaque, + const char *name, Error **errp) +{ + DeviceState *dev = DEVICE(obj); + Property *prop = opaque; + int16_t *ptr = qdev_get_prop_ptr(dev, prop); + Error *local_err = NULL; + int64_t value; + + if (dev->state != DEV_STATE_CREATED) { + error_set(errp, QERR_PERMISSION_DENIED); + return; + } + + visit_type_int(v, &value, name, &local_err); + if (local_err) { + error_propagate(errp, local_err); + return; + } + if (value < prop->info->min || value > prop->info->max) { + error_set(errp, QERR_PROPERTY_VALUE_OUT_OF_RANGE, + dev->id?:"", name, value, prop->info->min, + prop->info->max); + return; + } + + /* We rely on power-of-2 blocksizes for bitmasks */ + if ((value & (value - 1)) != 0) { + error_set(errp, QERR_PROPERTY_VALUE_NOT_POWER_OF_2, + dev->id?:"", name, value); + return; + } + + *ptr = value; +} + +PropertyInfo qdev_prop_blocksize = { + .name = "blocksize", + .get = get_int16, + .set = set_blocksize, + .min = 512, + .max = 65024, +}; + /* --- public helpers --- */ static Property *qdev_prop_walk(Property *props, const char *name) diff --git a/hw/qdev.h b/hw/qdev.h index a8df42f..1c10960 100644 --- a/hw/qdev.h +++ b/hw/qdev.h @@ -223,6 +223,7 @@ extern PropertyInfo qdev_prop_drive; extern PropertyInfo qdev_prop_netdev; extern PropertyInfo qdev_prop_vlan; extern PropertyInfo qdev_prop_pci_devfn; +extern PropertyInfo qdev_prop_blocksize; #define DEFINE_PROP(_name, _state, _field, _prop, _type) { \ .name = (_name), \ @@ -284,6 +285,8 @@ extern PropertyInfo qdev_prop_pci_devfn; #define DEFINE_PROP_LOSTTICKPOLICY(_n, _s, _f, _d) \ DEFINE_PROP_DEFAULT(_n, _s, _f, _d, qdev_prop_losttickpolicy, \ LostTickPolicy) +#define DEFINE_PROP_BLOCKSIZE(_n, _s, _f, _d) \ + DEFINE_PROP_DEFAULT(_n, _s, _f, _d, qdev_prop_blocksize, uint16_t) #define DEFINE_PROP_END_OF_LIST() \ {} diff --git a/qerror.c b/qerror.c index 1f565fc..96fbe71 100644 --- a/qerror.c +++ b/qerror.c @@ -241,6 +241,11 @@ static const QErrorStringTable qerror_table[] = { .desc = "Property '%(device).%(property)' can't find value '%(value)'", }, { + .error_fmt = QERR_PROPERTY_VALUE_NOT_POWER_OF_2, + .desc = "Property '%(device).%(property)' doesn't take " + "value '%(value)', it's not a power of 2", + }, + { .error_fmt = QERR_PROPERTY_VALUE_OUT_OF_RANGE, .desc = "Property '%(device).%(property)' doesn't take " "value %(value) (minimum: %(min), maximum: %(max))", diff --git a/qerror.h b/qerror.h index e16f9c2..5c23c1f 100644 --- a/qerror.h +++ b/qerror.h @@ -202,6 +202,10 @@ QError *qobject_to_qerror(const QObject *obj); #define QERR_PROPERTY_VALUE_NOT_FOUND \ "{ 'class': 'PropertyValueNotFound', 'data': { 'device': %s, 'property': %s, 'value': %s } }" +#define QERR_PROPERTY_VALUE_NOT_POWER_OF_2 \ + "{ 'class': 'PropertyValueNotPowerOf2', 'data': { " \ + "'device': %s, 'property': %s, 'value': %"PRId64" } }" + #define QERR_PROPERTY_VALUE_OUT_OF_RANGE \ "{ 'class': 'PropertyValueOutOfRange', 'data': { 'device': %s, 'property': %s, 'value': %"PRId64", 'min': %"PRId64", 'max': %"PRId64" } }"