From patchwork Tue Sep 22 02:31:39 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kent Gibson X-Patchwork-Id: 293422 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=-12.6 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT 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 1B6CEC4346E for ; Tue, 22 Sep 2020 02:35:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CD5112076E for ; Tue, 22 Sep 2020 02:35:37 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="J2mnH+1f" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729892AbgIVCfh (ORCPT ); Mon, 21 Sep 2020 22:35:37 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40526 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729870AbgIVCfg (ORCPT ); Mon, 21 Sep 2020 22:35:36 -0400 Received: from mail-pf1-x441.google.com (mail-pf1-x441.google.com [IPv6:2607:f8b0:4864:20::441]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DC679C061755; Mon, 21 Sep 2020 19:35:36 -0700 (PDT) Received: by mail-pf1-x441.google.com with SMTP id d9so11082455pfd.3; Mon, 21 Sep 2020 19:35:36 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=IEu7cL8AbWFB73T0YWP13NUyvMyAQFOwhfMAXVqx2jE=; b=J2mnH+1f0AYe6lzV+GL43lcdlHhCePCCXZKIh4Fg61K97F5M/GelrDAHdMnLFoMGdx mmbIwzJyXk93YldUMkQLu+1YTzizGu8zPUZJ5jD8z1Sbfuo+R5q61kVKr8V8rcSP4e2y 9LGDxJCjIHmXtdBUCwiDbtx8FnTm511VAx5Sx2GPT3nY6zCSPz1CohNPle3k0movz594 uTA4uW07aa72CuWSEBhgsoCk6s27oothvCfL26Cxs6MZPRhPz2ElQbmGIKMpGPzU6bLc zBv/dx/KFL7JIvTU2slPxuiGMRmACkr+fcR7fNHmgVctfZOmvTtr/kn+lgUdOPN+iH+3 HEAQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=IEu7cL8AbWFB73T0YWP13NUyvMyAQFOwhfMAXVqx2jE=; b=oEFMaolkhG52/E9PQjS7JmL9AtZm5RBptbqQi2pk3Gni+Cx9bBMXjppye7dOLBsLhX AVbbwDuhuKzEF14IT6HKZ+olqiYipm5MsREoceROT7RIn0JSAnLUjL3txA7qlaCaDTRD /dznxbJ0vXEiaP0CTcjo+neRFmEYr7cZ5BkZuYde4G3TluZdacEWRM8Gjt23Q3s6+D5/ Hn+Eb45/f2ftk8QyII39/c9Uj9R9oI5f2ke2beAimQHWhbqwL1EsdjyRHAG/+dPDhUzA oA3bUwERYljI3JDiTUi26O0zJIi8yegFsIXbB7vAcS0k7Qdd9jcOJv7Tmc+E/PBpFGBR xAaA== X-Gm-Message-State: AOAM533fYnCVvjubTdd9i7YEQ6NCLgFm3VVn0rwuMIdEYQDBpaHJaHNZ Zmv5KcrpvUNCa5RWxB4CDg2sJT7/2cmQEQ== X-Google-Smtp-Source: ABdhPJwmf48Fc5gLzKDsSf7HOUF6lpAyjzQ9OY+ifcgP6Xhsh4RHySJsPzlBYenymSmLh1pOgYZI5A== X-Received: by 2002:a63:4611:: with SMTP id t17mr1831158pga.225.1600742135840; Mon, 21 Sep 2020 19:35:35 -0700 (PDT) Received: from sol.lan (106-69-189-59.dyn.iinet.net.au. [106.69.189.59]) by smtp.gmail.com with ESMTPSA id j19sm13321390pfi.51.2020.09.21.19.35.32 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 21 Sep 2020 19:35:35 -0700 (PDT) From: Kent Gibson To: linux-kernel@vger.kernel.org, linux-gpio@vger.kernel.org, bgolaszewski@baylibre.com, linus.walleij@linaro.org, andy.shevchenko@gmail.com Cc: arnd@arndb.de, Kent Gibson Subject: [PATCH v9 08/20] gpiolib: cdev: support GPIO_V2_GET_LINEINFO_IOCTL and GPIO_V2_GET_LINEINFO_WATCH_IOCTL Date: Tue, 22 Sep 2020 10:31:39 +0800 Message-Id: <20200922023151.387447-9-warthog618@gmail.com> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200922023151.387447-1-warthog618@gmail.com> References: <20200922023151.387447-1-warthog618@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-gpio@vger.kernel.org Add support for GPIO_V2_GET_LINEINFO_IOCTL and GPIO_V2_GET_LINEINFO_WATCH_IOCTL. The core of this change is the event kfifo switching to contain struct gpioline_info_changed_v2, instead of v1 as v2 is richer. The two uAPI versions are mostly independent - other than where they both provide line info changes via reads on the chip fd. As the info change structs differ between v1 and v2, the infowatch implementation tracks which version of the infowatch ioctl, either GPIO_GET_LINEINFO_WATCH_IOCTL or GPIO_V2_GET_LINEINFO_WATCH_IOCTL, initiates the initial watch and returns the corresponding info change struct to the read. The version supported on that fd locks to that version on the first watch request, so subsequent watches from that process must use the same uAPI version. Signed-off-by: Kent Gibson --- Changes for v5: - as per cover letter Changes for v4: - replace strncpy with memcpy in gpio_v2_line_info_to_v1 drivers/gpio/gpiolib-cdev.c | 197 +++++++++++++++++++++++++++++++----- 1 file changed, 169 insertions(+), 28 deletions(-) diff --git a/drivers/gpio/gpiolib-cdev.c b/drivers/gpio/gpiolib-cdev.c index 7a3ed2617f74..d3857113f58c 100644 --- a/drivers/gpio/gpiolib-cdev.c +++ b/drivers/gpio/gpiolib-cdev.c @@ -181,7 +181,8 @@ static long linehandle_set_config(struct linehandle_state *lh, } blocking_notifier_call_chain(&desc->gdev->notifier, - GPIOLINE_CHANGED_CONFIG, desc); + GPIO_V2_LINE_CHANGED_CONFIG, + desc); } return 0; } @@ -353,7 +354,7 @@ static int linehandle_create(struct gpio_device *gdev, void __user *ip) } blocking_notifier_call_chain(&desc->gdev->notifier, - GPIOLINE_CHANGED_REQUESTED, desc); + GPIO_V2_LINE_CHANGED_REQUESTED, desc); dev_dbg(&gdev->dev, "registered chardev handle for line %d\n", offset); @@ -747,7 +748,7 @@ static int linereq_create(struct gpio_device *gdev, void __user *ip) } blocking_notifier_call_chain(&desc->gdev->notifier, - GPIOLINE_CHANGED_REQUESTED, desc); + GPIO_V2_LINE_CHANGED_REQUESTED, desc); dev_dbg(&gdev->dev, "registered chardev handle for line %d\n", offset); @@ -1094,7 +1095,7 @@ static int lineevent_create(struct gpio_device *gdev, void __user *ip) goto out_free_le; blocking_notifier_call_chain(&desc->gdev->notifier, - GPIOLINE_CHANGED_REQUESTED, desc); + GPIO_V2_LINE_CHANGED_REQUESTED, desc); irq = gpiod_to_irq(desc); if (irq <= 0) { @@ -1161,17 +1162,59 @@ static int lineevent_create(struct gpio_device *gdev, void __user *ip) return ret; } +static void gpio_v2_line_info_to_v1(struct gpio_v2_line_info *info_v2, + struct gpioline_info *info_v1) +{ + u64 flagsv2 = info_v2->flags; + + memcpy(info_v1->name, info_v2->name, sizeof(info_v1->name)); + memcpy(info_v1->consumer, info_v2->consumer, + sizeof(info_v1->consumer)); + info_v1->line_offset = info_v2->offset; + info_v1->flags = 0; + + if (flagsv2 & GPIO_V2_LINE_FLAG_USED) + info_v1->flags |= GPIOLINE_FLAG_KERNEL; + + if (flagsv2 & GPIO_V2_LINE_FLAG_OUTPUT) + info_v1->flags |= GPIOLINE_FLAG_IS_OUT; + + if (flagsv2 & GPIO_V2_LINE_FLAG_ACTIVE_LOW) + info_v1->flags |= GPIOLINE_FLAG_ACTIVE_LOW; + + if (flagsv2 & GPIO_V2_LINE_FLAG_OPEN_DRAIN) + info_v1->flags |= GPIOLINE_FLAG_OPEN_DRAIN; + if (flagsv2 & GPIO_V2_LINE_FLAG_OPEN_SOURCE) + info_v1->flags |= GPIOLINE_FLAG_OPEN_SOURCE; + + if (flagsv2 & GPIO_V2_LINE_FLAG_BIAS_PULL_UP) + info_v1->flags |= GPIOLINE_FLAG_BIAS_PULL_UP; + if (flagsv2 & GPIO_V2_LINE_FLAG_BIAS_PULL_DOWN) + info_v1->flags |= GPIOLINE_FLAG_BIAS_PULL_DOWN; + if (flagsv2 & GPIO_V2_LINE_FLAG_BIAS_DISABLED) + info_v1->flags |= GPIOLINE_FLAG_BIAS_DISABLE; +} + +static void gpio_v2_line_info_changed_to_v1( + struct gpio_v2_line_info_changed *lic_v2, + struct gpioline_info_changed *lic_v1) +{ + gpio_v2_line_info_to_v1(&lic_v2->info, &lic_v1->info); + lic_v1->timestamp = lic_v2->timestamp_ns; + lic_v1->event_type = lic_v2->event_type; +} + #endif /* CONFIG_GPIO_CDEV_V1 */ static void gpio_desc_to_lineinfo(struct gpio_desc *desc, - struct gpioline_info *info) + struct gpio_v2_line_info *info) { struct gpio_chip *gc = desc->gdev->chip; bool ok_for_pinctrl; unsigned long flags; memset(info, 0, sizeof(*info)); - info->line_offset = gpio_chip_hwgpio(desc); + info->offset = gpio_chip_hwgpio(desc); /* * This function takes a mutex so we must check this before taking @@ -1181,7 +1224,7 @@ static void gpio_desc_to_lineinfo(struct gpio_desc *desc, * lock common to both frameworks? */ ok_for_pinctrl = - pinctrl_gpio_can_use_line(gc->base + info->line_offset); + pinctrl_gpio_can_use_line(gc->base + info->offset); spin_lock_irqsave(&gpio_lock, flags); @@ -1202,23 +1245,27 @@ static void gpio_desc_to_lineinfo(struct gpio_desc *desc, test_bit(FLAG_EXPORT, &desc->flags) || test_bit(FLAG_SYSFS, &desc->flags) || !ok_for_pinctrl) - info->flags |= GPIOLINE_FLAG_KERNEL; + info->flags |= GPIO_V2_LINE_FLAG_USED; + if (test_bit(FLAG_IS_OUT, &desc->flags)) - info->flags |= GPIOLINE_FLAG_IS_OUT; + info->flags |= GPIO_V2_LINE_FLAG_OUTPUT; + else + info->flags |= GPIO_V2_LINE_FLAG_INPUT; + if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) - info->flags |= GPIOLINE_FLAG_ACTIVE_LOW; + info->flags |= GPIO_V2_LINE_FLAG_ACTIVE_LOW; + if (test_bit(FLAG_OPEN_DRAIN, &desc->flags)) - info->flags |= (GPIOLINE_FLAG_OPEN_DRAIN | - GPIOLINE_FLAG_IS_OUT); + info->flags |= GPIO_V2_LINE_FLAG_OPEN_DRAIN; if (test_bit(FLAG_OPEN_SOURCE, &desc->flags)) - info->flags |= (GPIOLINE_FLAG_OPEN_SOURCE | - GPIOLINE_FLAG_IS_OUT); + info->flags |= GPIO_V2_LINE_FLAG_OPEN_SOURCE; + if (test_bit(FLAG_BIAS_DISABLE, &desc->flags)) - info->flags |= GPIOLINE_FLAG_BIAS_DISABLE; + info->flags |= GPIO_V2_LINE_FLAG_BIAS_DISABLED; if (test_bit(FLAG_PULL_DOWN, &desc->flags)) - info->flags |= GPIOLINE_FLAG_BIAS_PULL_DOWN; + info->flags |= GPIO_V2_LINE_FLAG_BIAS_PULL_DOWN; if (test_bit(FLAG_PULL_UP, &desc->flags)) - info->flags |= GPIOLINE_FLAG_BIAS_PULL_UP; + info->flags |= GPIO_V2_LINE_FLAG_BIAS_PULL_UP; spin_unlock_irqrestore(&gpio_lock, flags); } @@ -1226,11 +1273,65 @@ static void gpio_desc_to_lineinfo(struct gpio_desc *desc, struct gpio_chardev_data { struct gpio_device *gdev; wait_queue_head_t wait; - DECLARE_KFIFO(events, struct gpioline_info_changed, 32); + DECLARE_KFIFO(events, struct gpio_v2_line_info_changed, 32); struct notifier_block lineinfo_changed_nb; unsigned long *watched_lines; +#ifdef CONFIG_GPIO_CDEV_V1 + atomic_t watch_abi_version; +#endif }; +#ifdef CONFIG_GPIO_CDEV_V1 +static int lineinfo_ensure_abi_version(struct gpio_chardev_data *cdata, + unsigned int version) +{ + int abiv = atomic_read(&cdata->watch_abi_version); + + if (abiv == 0) { + atomic_cmpxchg(&cdata->watch_abi_version, 0, version); + abiv = atomic_read(&cdata->watch_abi_version); + } + if (abiv != version) + return -EPERM; + return 0; +} +#endif + +static int lineinfo_get(struct gpio_chardev_data *cdev, void __user *ip, + bool watch) +{ + struct gpio_desc *desc; + struct gpio_v2_line_info lineinfo; + + if (copy_from_user(&lineinfo, ip, sizeof(lineinfo))) + return -EFAULT; + + if (memchr_inv(lineinfo.padding, 0, sizeof(lineinfo.padding))) + return -EINVAL; + + desc = gpiochip_get_desc(cdev->gdev->chip, lineinfo.offset); + if (IS_ERR(desc)) + return PTR_ERR(desc); + + if (watch) { +#ifdef CONFIG_GPIO_CDEV_V1 + if (lineinfo_ensure_abi_version(cdev, 2)) + return -EPERM; +#endif + if (test_and_set_bit(lineinfo.offset, cdev->watched_lines)) + return -EBUSY; + } + gpio_desc_to_lineinfo(desc, &lineinfo); + + if (copy_to_user(ip, &lineinfo, sizeof(lineinfo))) { + if (watch) + clear_bit(lineinfo.offset, cdev->watched_lines); + return -EFAULT; + } + + return 0; +} + /* * gpio_ioctl() - ioctl handler for the GPIO chardev */ @@ -1240,7 +1341,6 @@ static long gpio_ioctl(struct file *file, unsigned int cmd, unsigned long arg) struct gpio_device *gdev = cdev->gdev; struct gpio_chip *gc = gdev->chip; void __user *ip = (void __user *)arg; - struct gpio_desc *desc; __u32 offset; /* We fail any subsequent ioctl():s when the chip is gone */ @@ -1263,7 +1363,9 @@ static long gpio_ioctl(struct file *file, unsigned int cmd, unsigned long arg) return 0; #ifdef CONFIG_GPIO_CDEV_V1 } else if (cmd == GPIO_GET_LINEINFO_IOCTL) { + struct gpio_desc *desc; struct gpioline_info lineinfo; + struct gpio_v2_line_info lineinfo_v2; if (copy_from_user(&lineinfo, ip, sizeof(lineinfo))) return -EFAULT; @@ -1273,7 +1375,8 @@ static long gpio_ioctl(struct file *file, unsigned int cmd, unsigned long arg) if (IS_ERR(desc)) return PTR_ERR(desc); - gpio_desc_to_lineinfo(desc, &lineinfo); + gpio_desc_to_lineinfo(desc, &lineinfo_v2); + gpio_v2_line_info_to_v1(&lineinfo_v2, &lineinfo); if (copy_to_user(ip, &lineinfo, sizeof(lineinfo))) return -EFAULT; @@ -1283,7 +1386,9 @@ static long gpio_ioctl(struct file *file, unsigned int cmd, unsigned long arg) } else if (cmd == GPIO_GET_LINEEVENT_IOCTL) { return lineevent_create(gdev, ip); } else if (cmd == GPIO_GET_LINEINFO_WATCH_IOCTL) { + struct gpio_desc *desc; struct gpioline_info lineinfo; + struct gpio_v2_line_info lineinfo_v2; if (copy_from_user(&lineinfo, ip, sizeof(lineinfo))) return -EFAULT; @@ -1293,10 +1398,14 @@ static long gpio_ioctl(struct file *file, unsigned int cmd, unsigned long arg) if (IS_ERR(desc)) return PTR_ERR(desc); + if (lineinfo_ensure_abi_version(cdev, 1)) + return -EPERM; + if (test_and_set_bit(lineinfo.line_offset, cdev->watched_lines)) return -EBUSY; - gpio_desc_to_lineinfo(desc, &lineinfo); + gpio_desc_to_lineinfo(desc, &lineinfo_v2); + gpio_v2_line_info_to_v1(&lineinfo_v2, &lineinfo); if (copy_to_user(ip, &lineinfo, sizeof(lineinfo))) { clear_bit(lineinfo.line_offset, cdev->watched_lines); @@ -1305,6 +1414,10 @@ static long gpio_ioctl(struct file *file, unsigned int cmd, unsigned long arg) return 0; #endif /* CONFIG_GPIO_CDEV_V1 */ + } else if (cmd == GPIO_V2_GET_LINEINFO_IOCTL || + cmd == GPIO_V2_GET_LINEINFO_WATCH_IOCTL) { + return lineinfo_get(cdev, ip, + cmd == GPIO_V2_GET_LINEINFO_WATCH_IOCTL); } else if (cmd == GPIO_V2_GET_LINE_IOCTL) { return linereq_create(gdev, ip); } else if (cmd == GPIO_GET_LINEINFO_UNWATCH_IOCTL) { @@ -1340,7 +1453,7 @@ static int lineinfo_changed_notify(struct notifier_block *nb, unsigned long action, void *data) { struct gpio_chardev_data *cdev = to_gpio_chardev_data(nb); - struct gpioline_info_changed chg; + struct gpio_v2_line_info_changed chg; struct gpio_desc *desc = data; int ret; @@ -1349,7 +1462,7 @@ static int lineinfo_changed_notify(struct notifier_block *nb, memset(&chg, 0, sizeof(chg)); chg.event_type = action; - chg.timestamp = ktime_get_ns(); + chg.timestamp_ns = ktime_get_ns(); gpio_desc_to_lineinfo(desc, &chg.info); ret = kfifo_in_spinlocked(&cdev->events, &chg, 1, &cdev->wait.lock); @@ -1380,12 +1493,16 @@ static ssize_t lineinfo_watch_read(struct file *file, char __user *buf, size_t count, loff_t *off) { struct gpio_chardev_data *cdev = file->private_data; - struct gpioline_info_changed event; + struct gpio_v2_line_info_changed event; ssize_t bytes_read = 0; int ret; + size_t event_size; - if (count < sizeof(event)) +#ifndef CONFIG_GPIO_CDEV_V1 + event_size = sizeof(struct gpio_v2_line_info_changed); + if (count < event_size) return -EINVAL; +#endif do { spin_lock(&cdev->wait.lock); @@ -1407,7 +1524,17 @@ static ssize_t lineinfo_watch_read(struct file *file, char __user *buf, return ret; } } - +#ifdef CONFIG_GPIO_CDEV_V1 + /* must be after kfifo check so watch_abi_version is set */ + if (atomic_read(&cdev->watch_abi_version) == 2) + event_size = sizeof(struct gpio_v2_line_info_changed); + else + event_size = sizeof(struct gpioline_info_changed); + if (count < event_size) { + spin_unlock(&cdev->wait.lock); + return -EINVAL; + } +#endif ret = kfifo_out(&cdev->events, &event, 1); spin_unlock(&cdev->wait.lock); if (ret != 1) { @@ -1416,9 +1543,23 @@ static ssize_t lineinfo_watch_read(struct file *file, char __user *buf, /* We should never get here. See lineevent_read(). */ } - if (copy_to_user(buf + bytes_read, &event, sizeof(event))) +#ifdef CONFIG_GPIO_CDEV_V1 + if (event_size == sizeof(struct gpio_v2_line_info_changed)) { + if (copy_to_user(buf + bytes_read, &event, event_size)) + return -EFAULT; + } else { + struct gpioline_info_changed event_v1; + + gpio_v2_line_info_changed_to_v1(&event, &event_v1); + if (copy_to_user(buf + bytes_read, &event_v1, + event_size)) + return -EFAULT; + } +#else + if (copy_to_user(buf + bytes_read, &event, event_size)) return -EFAULT; - bytes_read += sizeof(event); +#endif + bytes_read += event_size; } while (count >= bytes_read + sizeof(event)); return bytes_read;