Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751858AbbHLS4Y (ORCPT ); Wed, 12 Aug 2015 14:56:24 -0400 Received: from mx1.redhat.com ([209.132.183.28]:57112 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751717AbbHLS4V (ORCPT ); Wed, 12 Aug 2015 14:56:21 -0400 Message-ID: <1439405780.4023.527.camel@redhat.com> Subject: Re: [PATCH v3 03/10] VFIO: platform: single handler using function pointer From: Alex Williamson To: Eric Auger Cc: eric.auger@st.com, linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org, christoffer.dall@linaro.org, marc.zyngier@arm.com, feng.wu@intel.com, linux-kernel@vger.kernel.org, patches@linaro.org, pbonzini@redhat.com Date: Wed, 12 Aug 2015 12:56:20 -0600 In-Reply-To: <1439212864-12954-4-git-send-email-eric.auger@linaro.org> References: <1439212864-12954-1-git-send-email-eric.auger@linaro.org> <1439212864-12954-4-git-send-email-eric.auger@linaro.org> Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3282 Lines: 99 On Mon, 2015-08-10 at 15:20 +0200, Eric Auger wrote: > A single handler now is registered whatever the use case: automasked > or not. A function pointer is set according to the wished behavior > and the handler calls this function. > > The irq lock is taken/released in the root handler. eventfd_signal can > be called in regions not allowed to sleep. > > Signed-off-by: Eric Auger > > --- > > v4: creation > --- > drivers/vfio/platform/vfio_platform_irq.c | 21 +++++++++++++++------ > drivers/vfio/platform/vfio_platform_private.h | 1 + > 2 files changed, 16 insertions(+), 6 deletions(-) > > diff --git a/drivers/vfio/platform/vfio_platform_irq.c b/drivers/vfio/platform/vfio_platform_irq.c > index 40f057a..b31b1f0 100644 > --- a/drivers/vfio/platform/vfio_platform_irq.c > +++ b/drivers/vfio/platform/vfio_platform_irq.c > @@ -148,11 +148,8 @@ static int vfio_platform_set_irq_unmask(struct vfio_platform_device *vdev, > static irqreturn_t vfio_automasked_irq_handler(int irq, void *dev_id) > { > struct vfio_platform_irq *irq_ctx = dev_id; > - unsigned long flags; > int ret = IRQ_NONE; > > - spin_lock_irqsave(&irq_ctx->lock, flags); > - > if (!irq_ctx->masked) { > ret = IRQ_HANDLED; > > @@ -161,8 +158,6 @@ static irqreturn_t vfio_automasked_irq_handler(int irq, void *dev_id) > irq_ctx->masked = true; > } > > - spin_unlock_irqrestore(&irq_ctx->lock, flags); > - > if (ret == IRQ_HANDLED) > eventfd_signal(irq_ctx->trigger, 1); Has this been run with lockdep to check whether this is safe to call with spinlock_irqsave held? > > @@ -178,6 +173,19 @@ static irqreturn_t vfio_irq_handler(int irq, void *dev_id) > return IRQ_HANDLED; > } > > +static irqreturn_t vfio_handler(int irq, void *dev_id) > +{ > + struct vfio_platform_irq *irq_ctx = dev_id; > + unsigned long flags; > + irqreturn_t ret; > + > + spin_lock_irqsave(&irq_ctx->lock, flags); > + ret = irq_ctx->handler(irq, dev_id); > + spin_unlock_irqrestore(&irq_ctx->lock, flags); > + > + return ret; > +} > + > static void vfio_platform_irq_bypass_stop(struct irq_bypass_producer *prod) > { > } > @@ -229,9 +237,10 @@ static int vfio_set_trigger(struct vfio_platform_device *vdev, int index, > } > > irq->trigger = trigger; > + irq->handler = handler; > > irq_set_status_flags(irq->hwirq, IRQ_NOAUTOEN); > - ret = request_irq(irq->hwirq, handler, 0, irq->name, irq); > + ret = request_irq(irq->hwirq, vfio_handler, 0, irq->name, irq); > if (ret) { > kfree(irq->name); > eventfd_ctx_put(trigger); > diff --git a/drivers/vfio/platform/vfio_platform_private.h b/drivers/vfio/platform/vfio_platform_private.h > index 8b4f814..f848a6b 100644 > --- a/drivers/vfio/platform/vfio_platform_private.h > +++ b/drivers/vfio/platform/vfio_platform_private.h > @@ -40,6 +40,7 @@ struct vfio_platform_irq { > struct virqfd *mask; > struct irq_bypass_producer producer; > bool forwarded; > + irqreturn_t (*handler)(int irq, void *dev_id); > }; > > struct vfio_platform_region { -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/