From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.3 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6B51BC54E4B for ; Tue, 12 May 2020 04:17:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3B78820730 for ; Tue, 12 May 2020 04:17:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1589257050; bh=9nZObMtiSqGbLsDXcwbdsv1VkgpqhzXRBE6FnvrYmHk=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=XlzZ2kqBg2qe6rO2/OJy5VEM3IGM+JTqRJo/JgNngf+fh7Y+HpKxt8ijhAxz8oCDe hu3/opZiWge6NNPF8MqAsfuqMbg5JgT+qTMZoE/PvXZ9+Iklb5JgpVmp8eGpAjittc qA6BFQCE98SDW5xV/+VgDaOZCTfh4CKCNl0QkHR8= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726027AbgELER3 (ORCPT ); Tue, 12 May 2020 00:17:29 -0400 Received: from mail-pj1-f66.google.com ([209.85.216.66]:35478 "EHLO mail-pj1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725776AbgELER2 (ORCPT ); Tue, 12 May 2020 00:17:28 -0400 Received: by mail-pj1-f66.google.com with SMTP id ms17so8763205pjb.0; Mon, 11 May 2020 21:17:26 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=3kzLridzmuQvWW32kza8p9BBRXJ+XCKQASu0Ns/21q4=; b=G0yVAHFDhDhTBNRNJYELAgEURO7bFjo72lO8BT1V2j4U7shi+VEptKErPbs4YjXtF2 AR6nv9tsJa+B/NbGVyRRtGndlTtyX/XJHguZgx4C2j4eZs0lsd3eRaj5o7w3drVCqcfL eL4UN2GbuLu4DybRmnaHt5bVRJ7LQNzs+x30CU1KszQnUmrsY2Hp2AQNfoh2j7Y/uyWb ZO6ci7ZimDj3ZuPJ6B2OfQ5Yp3dzxUp6tGoXz5hXHABEOCh6ADLq8UyD60/H4DbSrPCB OsWVe0IAvs3v8tyLGPYiILDNe+Md0SAFjuMV+IdIGpXUyda8SvEOxoTAEUYQ8D56Xk5B oyvA== X-Gm-Message-State: AGi0PuY01eOAWu0Ag5iZT11OwyUENcnoSxt57im/TNn7M8lEZZy6S9Ia KPePaF5KKQVwBo0lJzl6fELVuoU+ X-Google-Smtp-Source: APiQypK0/C6xxdyvM3mkNy3jWZx+woseH5MpEDJrEcS3lXjoSwts/uf7XCdQbIQN2zgYlzvfry4JVw== X-Received: by 2002:a17:90a:ba88:: with SMTP id t8mr25155525pjr.182.1589257046205; Mon, 11 May 2020 21:17:26 -0700 (PDT) Received: from localhost ([2601:647:5b00:1161:a4cc:eef9:fbc0:2781]) by smtp.gmail.com with ESMTPSA id a30sm9280110pgm.44.2020.05.11.21.17.24 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 11 May 2020 21:17:25 -0700 (PDT) Date: Mon, 11 May 2020 21:16:34 -0700 From: Moritz Fischer To: Xu Yilun Cc: mdf@kernel.org, linux-fpga@vger.kernel.org, linux-kernel@vger.kernel.org, trix@redhat.com, bhu@redhat.com, Luwei Kang , Wu Hao Subject: Re: [PATCH v5 3/7] fpga: dfl: introduce interrupt trigger setting API Message-ID: <20200512041634.GC110219@epycbox.lan> References: <1587370303-25568-1-git-send-email-yilun.xu@intel.com> <1587370303-25568-4-git-send-email-yilun.xu@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1587370303-25568-4-git-send-email-yilun.xu@intel.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Apr 20, 2020 at 04:11:39PM +0800, Xu Yilun wrote: > FPGA user applications may be interested in interrupts generated by > DFL features. For example, users can implement their own FPGA > logics with interrupts enabled in AFU (Accelerated Function Unit, > dynamic region of DFL based FPGA). So user applications need to be > notified to handle these interrupts. > > In order to allow userspace applications to monitor interrupts, > driver requires userspace to provide eventfds as interrupt > notification channels. Applications then poll/select on the eventfds > to get notified. > > This patch introduces a generic helper functions to do eventfds binding > with given interrupts. > > Sub feature drivers are expected to use XXX_GET_IRQ_NUM to query irq > info, and XXX_SET_IRQ to set eventfds for interrupts. This patch also > introduces helper functions for these 2 ioctls. > > Signed-off-by: Luwei Kang > Signed-off-by: Wu Hao > Signed-off-by: Xu Yilun > Acked-by: Wu Hao > ---- > v2: use unsigned int instead of int for irq array indexes in > dfl_fpga_set_irq_triggers() > Improves comments for NULL fds param in dfl_fpga_set_irq_triggers() > v3: Improve comments of dfl_fpga_set_irq_triggers() > refines code for dfl_fpga_set_irq_triggers, delete local variable j > v4: Introduce 2 helper functions to help handle the XXX_GET_IRQ_NUM & > XXX_SET_IRQ ioctls for sub feature drivers. > v5: Some minor fix for Hao's comments > --- > drivers/fpga/dfl.c | 156 ++++++++++++++++++++++++++++++++++++++++++ > drivers/fpga/dfl.h | 17 +++++ > include/uapi/linux/fpga-dfl.h | 13 ++++ > 3 files changed, 186 insertions(+) > > diff --git a/drivers/fpga/dfl.c b/drivers/fpga/dfl.c > index b49fbed..208d8f0 100644 > --- a/drivers/fpga/dfl.c > +++ b/drivers/fpga/dfl.c > @@ -10,7 +10,9 @@ > * Wu Hao > * Xiao Guangrong > */ > +#include > #include > +#include > > #include "dfl.h" > > @@ -534,6 +536,7 @@ static int build_info_commit_dev(struct build_feature_devs_info *binfo) > unsigned int i; > > /* save resource information for each feature */ > + feature->dev = fdev; > feature->id = finfo->fid; > feature->resource_index = index; > feature->ioaddr = finfo->ioaddr; > @@ -1395,6 +1398,159 @@ int dfl_fpga_cdev_config_ports_vf(struct dfl_fpga_cdev *cdev, int num_vfs) > } > EXPORT_SYMBOL_GPL(dfl_fpga_cdev_config_ports_vf); > > +static irqreturn_t dfl_irq_handler(int irq, void *arg) > +{ > + struct eventfd_ctx *trigger = arg; > + > + eventfd_signal(trigger, 1); > + return IRQ_HANDLED; > +} > + > +static int do_set_irq_trigger(struct dfl_feature *feature, unsigned int idx, > + int fd) > +{ > + struct platform_device *pdev = feature->dev; > + struct eventfd_ctx *trigger; > + int irq, ret; > + > + if (idx >= feature->nr_irqs) > + return -EINVAL; > + > + irq = feature->irq_ctx[idx].irq; > + > + if (feature->irq_ctx[idx].trigger) { > + free_irq(irq, feature->irq_ctx[idx].trigger); > + kfree(feature->irq_ctx[idx].name); > + eventfd_ctx_put(feature->irq_ctx[idx].trigger); > + feature->irq_ctx[idx].trigger = NULL; > + } > + > + if (fd < 0) > + return 0; > + > + feature->irq_ctx[idx].name = > + kasprintf(GFP_KERNEL, "fpga-irq[%u](%s-%llx)", idx, > + dev_name(&pdev->dev), > + (unsigned long long)feature->id); > + if (!feature->irq_ctx[idx].name) > + return -ENOMEM; > + > + trigger = eventfd_ctx_fdget(fd); > + if (IS_ERR(trigger)) { > + ret = PTR_ERR(trigger); > + goto free_name; > + } > + > + ret = request_irq(irq, dfl_irq_handler, 0, > + feature->irq_ctx[idx].name, trigger); > + if (!ret) { > + feature->irq_ctx[idx].trigger = trigger; > + return ret; > + } > + > + eventfd_ctx_put(trigger); > +free_name: > + kfree(feature->irq_ctx[idx].name); > + > + return ret; > +} > + > +/** > + * dfl_fpga_set_irq_triggers - set eventfd triggers for dfl feature interrupts > + * > + * @feature: dfl sub feature. > + * @start: start of irq index in this dfl sub feature. > + * @count: number of irqs. > + * @fds: eventfds to bind with irqs. unbind related irq if fds[n] is negative. > + * unbind "count" specified number of irqs if fds ptr is NULL. > + * > + * Bind given eventfds with irqs in this dfl sub feature. Unbind related irq if > + * fds[n] is negative. Unbind "count" specified number of irqs if fds ptr is > + * NULL. > + * > + * Return: 0 on success, negative error code otherwise. > + */ > +int dfl_fpga_set_irq_triggers(struct dfl_feature *feature, unsigned int start, > + unsigned int count, int32_t *fds) > +{ > + unsigned int i; > + int ret = 0; > + > + if (start + count < start || start + count > feature->nr_irqs) > + return -EINVAL; Up to you, but have you considered to break up the condition above into two if () ? > + > + for (i = 0; i < count; i++) { > + int fd = fds ? fds[i] : -1; > + > + ret = do_set_irq_trigger(feature, start + i, fd); > + if (ret) { > + while (i--) > + do_set_irq_trigger(feature, start + i, -1); > + break; > + } > + } > + > + return ret; > +} > +EXPORT_SYMBOL_GPL(dfl_fpga_set_irq_triggers); > + > +/** > + * dfl_feature_ioctl_get_num_irqs - dfl feature _GET_IRQ_NUM ioctl interface. > + * @pdev: the feature device which has the sub feature > + * @feature: the dfl sub feature > + * @arg: ioctl argument > + * > + * Return: 0 on success, negative error code otherwise. > + */ > +long dfl_feature_ioctl_get_num_irqs(struct platform_device *pdev, > + struct dfl_feature *feature, > + unsigned long arg) > +{ > + return put_user(feature->nr_irqs, (__u32 __user *)arg); > +} > +EXPORT_SYMBOL_GPL(dfl_feature_ioctl_get_num_irqs); > + > +/** > + * dfl_feature_ioctl_set_irq - dfl feature _SET_IRQ ioctl interface. > + * @pdev: the feature device which has the sub feature > + * @feature: the dfl sub feature > + * @arg: ioctl argument > + * > + * Return: 0 on success, negative error code otherwise. > + */ > +long dfl_feature_ioctl_set_irq(struct platform_device *pdev, > + struct dfl_feature *feature, > + unsigned long arg) > +{ > + struct dfl_feature_platform_data *pdata = dev_get_platdata(&pdev->dev); > + struct dfl_fpga_irq_set hdr; > + s32 *fds; > + long ret; > + > + if (!feature->nr_irqs) > + return -ENOENT; > + > + if (copy_from_user(&hdr, (void __user *)arg, sizeof(hdr))) > + return -EFAULT; > + > + if (!hdr.count || (hdr.start + hdr.count > feature->nr_irqs) || > + (hdr.start + hdr.count < hdr.start)) > + return -EINVAL; > + > + fds = memdup_user((void __user *)(arg + sizeof(hdr)), > + hdr.count * sizeof(s32)); > + if (IS_ERR(fds)) > + return PTR_ERR(fds); > + > + mutex_lock(&pdata->lock); > + ret = dfl_fpga_set_irq_triggers(feature, hdr.start, hdr.count, fds); > + mutex_unlock(&pdata->lock); > + > + kfree(fds); > + return ret; > +} > +EXPORT_SYMBOL_GPL(dfl_feature_ioctl_set_irq); > + > static void __exit dfl_fpga_exit(void) > { > dfl_chardev_uinit(); > diff --git a/drivers/fpga/dfl.h b/drivers/fpga/dfl.h > index 4bc165f..f7a8c59 100644 > --- a/drivers/fpga/dfl.h > +++ b/drivers/fpga/dfl.h > @@ -17,7 +17,9 @@ > #include > #include > #include > +#include > #include > +#include > #include > #include > #include > @@ -213,14 +215,19 @@ struct dfl_feature_driver { > * struct dfl_feature_irq_ctx - dfl private feature interrupt context > * > * @irq: Linux IRQ number of this interrupt. > + * @trigger: eventfd context to signal when interrupt happens. > + * @name: irq name needed when requesting irq. > */ > struct dfl_feature_irq_ctx { > int irq; > + struct eventfd_ctx *trigger; > + char *name; > }; > > /** > * struct dfl_feature - sub feature of the feature devices > * > + * @dev: ptr to pdev of the feature device which has the sub feature. > * @id: sub feature id. > * @resource_index: each sub feature has one mmio resource for its registers. > * this index is used to find its mmio resource from the > @@ -231,6 +238,7 @@ struct dfl_feature_irq_ctx { > * @ops: ops of this sub feature. > */ > struct dfl_feature { > + struct platform_device *dev; > u64 id; > int resource_index; > void __iomem *ioaddr; > @@ -506,4 +514,13 @@ int dfl_fpga_cdev_release_port(struct dfl_fpga_cdev *cdev, int port_id); > int dfl_fpga_cdev_assign_port(struct dfl_fpga_cdev *cdev, int port_id); > void dfl_fpga_cdev_config_ports_pf(struct dfl_fpga_cdev *cdev); > int dfl_fpga_cdev_config_ports_vf(struct dfl_fpga_cdev *cdev, int num_vf); > +int dfl_fpga_set_irq_triggers(struct dfl_feature *feature, unsigned int start, > + unsigned int count, int32_t *fds); > +long dfl_feature_ioctl_get_num_irqs(struct platform_device *pdev, > + struct dfl_feature *feature, > + unsigned long arg); > +long dfl_feature_ioctl_set_irq(struct platform_device *pdev, > + struct dfl_feature *feature, > + unsigned long arg); > + > #endif /* __FPGA_DFL_H */ > diff --git a/include/uapi/linux/fpga-dfl.h b/include/uapi/linux/fpga-dfl.h > index ec70a0746..7331350 100644 > --- a/include/uapi/linux/fpga-dfl.h > +++ b/include/uapi/linux/fpga-dfl.h > @@ -151,6 +151,19 @@ struct dfl_fpga_port_dma_unmap { > > #define DFL_FPGA_PORT_DMA_UNMAP _IO(DFL_FPGA_MAGIC, DFL_PORT_BASE + 4) > > +/** > + * struct dfl_fpga_irq_set - the argument for DFL_FPGA_XXX_SET_IRQ ioctl. > + * > + * @start: Index of the first irq. > + * @count: The number of eventfd handler. > + * @evtfds: Eventfd handlers. > + */ > +struct dfl_fpga_irq_set { > + __u32 start; > + __u32 count; > + __s32 evtfds[]; > +}; > + > /* IOCTLs for FME file descriptor */ > > /** > -- > 2.7.4 > Thanks, Moritz