| Message ID | 1475900595-8375-4-git-send-email-bjorn.andersson@linaro.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 10/08/2016 06:23 AM, Bjorn Andersson wrote: > This driver allows rpmsg instances to expose access to rpmsg endpoints > to user space processes. It provides a control interface, allowing > userspace to export endpoints and an endpoint interface for each exposed > endpoint. > > The implementation is based on prior art by Texas Instrument, Google, > PetaLogix and was derived from a FreeRTOS performance statistics driver > written by Michal Simek. > > The control interface provides a "create endpoint" ioctl, which is fed a > name, source and destination address. The three values are used to > create the endpoint, in a backend-specific way, and a rpmsg endpoint > device is created - with the three parameters are available in sysfs for > udev usage. > > E.g. to create an endpoint device for one of the Qualcomm SMD channel > related to DIAG one would issue: > > struct rpmsg_endpoint_info info = { "DIAG_CNTL", 0, 0 }; > int fd = open("/dev/rpmsg_ctrl0", O_RDWR); > ioctl(fd, RPMSG_CREATE_EPT_IOCTL, &info); > > Each created endpoint device shows up as an individual character device > in /dev, allowing permission to be controlled on a per-endpoint basis. > The rpmsg endpoint will be created and destroyed following the opening > and closing of the endpoint device, allowing rpmsg backends to open and > close the physical channel, if supported by the wire protocol. > > Cc: Marek Novak <marek.novak@nxp.com> > Cc: Matteo Sartori <matteo.sartori@t3lab.it> > Cc: Michal Simek <monstr@monstr.eu> > Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org> > --- > Documentation/ioctl/ioctl-number.txt | 1 + > drivers/rpmsg/Makefile | 2 +- > drivers/rpmsg/rpmsg_char.c | 576 +++++++++++++++++++++++++++++++++++ > drivers/rpmsg/rpmsg_internal.h | 2 + > include/uapi/linux/rpmsg.h | 35 +++ > 5 files changed, 615 insertions(+), 1 deletion(-) > create mode 100644 drivers/rpmsg/rpmsg_char.c > create mode 100644 include/uapi/linux/rpmsg.h > > diff --git a/Documentation/ioctl/ioctl-number.txt b/Documentation/ioctl/ioctl-number.txt > index 81c7f2bb7daf..08244bea5048 100644 > --- a/Documentation/ioctl/ioctl-number.txt > +++ b/Documentation/ioctl/ioctl-number.txt > @@ -321,6 +321,7 @@ Code Seq#(hex) Include File Comments > 0xB1 00-1F PPPoX <mailto:mostrows@styx.uwaterloo.ca> > 0xB3 00 linux/mmc/ioctl.h > 0xB4 00-0F linux/gpio.h <mailto:linux-gpio@vger.kernel.org> > +0xB5 00-0F uapi/linux/rpmsg.h <mailto:linux-remoteproc@vger.kernel.org> > 0xC0 00-0F linux/usb/iowarrior.h > 0xCA 00-0F uapi/misc/cxl.h > 0xCA 80-8F uapi/scsi/cxlflash_ioctl.h > diff --git a/drivers/rpmsg/Makefile b/drivers/rpmsg/Makefile > index ae9c9132cf76..5daf1209b77d 100644 > --- a/drivers/rpmsg/Makefile > +++ b/drivers/rpmsg/Makefile > @@ -1,3 +1,3 @@ > -obj-$(CONFIG_RPMSG) += rpmsg_core.o > +obj-$(CONFIG_RPMSG) += rpmsg_core.o rpmsg_char.o Hi Bjorn, Could you please create a dedicated Kconfig entry for this new interface? This should be an option like i2C_dev. Regards, Loic > obj-$(CONFIG_RPMSG_QCOM_SMD) += qcom_smd.o > obj-$(CONFIG_RPMSG_VIRTIO) += virtio_rpmsg_bus.o > diff --git a/drivers/rpmsg/rpmsg_char.c b/drivers/rpmsg/rpmsg_char.c > new file mode 100644 > index 000000000000..a398a63e8d44 > --- /dev/null > +++ b/drivers/rpmsg/rpmsg_char.c > @@ -0,0 +1,576 @@ > +/* > + * Copyright (c) 2016, Linaro Ltd. > + * Copyright (c) 2012, Michal Simek <monstr@monstr.eu> > + * Copyright (c) 2012, PetaLogix > + * Copyright (c) 2011, Texas Instruments, Inc. > + * Copyright (c) 2011, Google, Inc. > + * > + * Based on rpmsg performance statistics driver by Michal Simek, which in turn > + * was based on TI & Google OMX rpmsg driver. > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License version 2 and > + * only version 2 as published by the Free Software Foundation. > + * > + * This program is distributed in the hope that it will be useful, > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > + * GNU General Public License for more details. > + */ > +#include <linux/cdev.h> > +#include <linux/device.h> > +#include <linux/fs.h> > +#include <linux/idr.h> > +#include <linux/kernel.h> > +#include <linux/module.h> > +#include <linux/rpmsg.h> > +#include <linux/skbuff.h> > +#include <linux/slab.h> > +#include <linux/uaccess.h> > +#include <uapi/linux/rpmsg.h> > + > +#include "rpmsg_internal.h" > + > +#define RPMSG_DEV_MAX 256 > + > +static dev_t rpmsg_major; > +static struct class *rpmsg_class; > + > +static DEFINE_IDA(rpmsg_ctrl_ida); > +static DEFINE_IDA(rpmsg_ept_ida); > +static DEFINE_IDA(rpmsg_minor_ida); > + > +#define dev_to_eptdev(dev) container_of(dev, struct rpmsg_eptdev, dev) > +#define cdev_to_eptdev(i_cdev) container_of(i_cdev, struct rpmsg_eptdev, cdev) > + > +#define dev_to_ctrldev(dev) container_of(dev, struct rpmsg_ctrldev, dev) > +#define cdev_to_ctrldev(i_cdev) container_of(i_cdev, struct rpmsg_ctrldev, cdev) > + > +struct rpmsg_ctrldev { > + struct rpmsg_device *rpdev; > + struct cdev cdev; > + struct device dev; > +}; > + > +struct rpmsg_eptdev { > + struct device dev; > + struct cdev cdev; > + > + struct rpmsg_device *rpdev; > + struct rpmsg_channel_info chinfo; > + > + struct mutex ept_lock; > + struct rpmsg_endpoint *ept; > + > + spinlock_t queue_lock; > + struct sk_buff_head queue; > + wait_queue_head_t readq; > +}; > + > +static int rpmsg_eptdev_destroy(struct rpmsg_eptdev *eptdev); > + > + > +static int rpmsg_cdev_register(struct device *dev, > + struct cdev *cdev, > + const struct file_operations *fops, > + dev_t *assigned_devt) > +{ > + dev_t devt; > + int ret; > + > + ret = ida_simple_get(&rpmsg_minor_ida, 0, 0, GFP_KERNEL); > + if (ret < 0) > + return ret; > + > + devt = MKDEV(MAJOR(rpmsg_major), ret); > + > + cdev_init(cdev, fops); > + cdev->owner = THIS_MODULE; > + ret = cdev_add(cdev, devt, 1); > + if (ret < 0) { > + dev_err(dev, "cdev_add failed: %d\n", ret); > + ida_simple_remove(&rpmsg_minor_ida, MINOR(devt)); > + return ret; > + } > + > + *assigned_devt = devt; > + return 0; > +} > + > +static int rpmsg_ept_cb(struct rpmsg_device *rpdev, void *buf, int len, > + void *priv, u32 addr) > +{ > + struct rpmsg_eptdev *eptdev = priv; > + struct sk_buff *skb; > + > + skb = alloc_skb(len, GFP_ATOMIC); > + if (!skb) > + return -ENOMEM; > + > + memcpy(skb_put(skb, len), buf, len); > + > + spin_lock(&eptdev->queue_lock); > + skb_queue_tail(&eptdev->queue, skb); > + spin_unlock(&eptdev->queue_lock); > + > + /* wake up any blocking processes, waiting for new data */ > + wake_up_interruptible(&eptdev->readq); > + > + return 0; > +} > + > +static int rpmsg_eptdev_open(struct inode *inode, struct file *filp) > +{ > + struct rpmsg_eptdev *eptdev = cdev_to_eptdev(inode->i_cdev); > + struct rpmsg_endpoint *ept; > + struct rpmsg_device *rpdev = eptdev->rpdev; > + struct device *dev = &eptdev->dev; > + > + get_device(dev); > + > + ept = rpmsg_create_ept(rpdev, rpmsg_ept_cb, eptdev, eptdev->chinfo); > + if (!ept) { > + dev_err(dev, "failed to open %s\n", eptdev->chinfo.name); > + put_device(dev); > + return -EINVAL; > + } > + > + eptdev->ept = ept; > + filp->private_data = eptdev; > + > + return 0; > +} > + > +static int rpmsg_eptdev_release(struct inode *inode, struct file *filp) > +{ > + struct rpmsg_eptdev *eptdev = cdev_to_eptdev(inode->i_cdev); > + struct device *dev = &eptdev->dev; > + struct sk_buff *skb; > + > + /* Close the endpoint, if it's not already destroyed by the parent */ > + if (eptdev->ept) > + rpmsg_destroy_ept(eptdev->ept); > + > + /* Discard all SKBs */ > + while (!skb_queue_empty(&eptdev->queue)) { > + skb = skb_dequeue(&eptdev->queue); > + kfree_skb(skb); > + } > + > + put_device(dev); > + > + return 0; > +} > + > +static long rpmsg_eptdev_ioctl(struct file *fp, unsigned int cmd, > + unsigned long arg) > +{ > + struct rpmsg_eptdev *eptdev = fp->private_data; > + > + if (cmd != RPMSG_DESTROY_EPT_IOCTL) > + return -EINVAL; > + > + return rpmsg_eptdev_destroy(eptdev); > +} > + > +static ssize_t rpmsg_eptdev_read(struct file *filp, char __user *buf, > + size_t count, loff_t *f_pos) > +{ > + struct rpmsg_eptdev *eptdev = filp->private_data; > + unsigned long flags; > + struct sk_buff *skb; > + int use; > + > + spin_lock_irqsave(&eptdev->queue_lock, flags); > + > + /* Wait for data in the queue */ > + if (skb_queue_empty(&eptdev->queue)) { > + spin_unlock_irqrestore(&eptdev->queue_lock, flags); > + > + if (filp->f_flags & O_NONBLOCK) > + return -EAGAIN; > + > + /* Wait until we get data or the endpoint goes away */ > + if (wait_event_interruptible(eptdev->readq, > + !skb_queue_empty(&eptdev->queue) || > + !eptdev->ept)) > + return -ERESTARTSYS; > + > + /* We lost the endpoint while waiting */ > + if (!eptdev->ept) > + return -EPIPE; > + > + spin_lock_irqsave(&eptdev->queue_lock, flags); > + } > + > + skb = skb_dequeue(&eptdev->queue); > + if (!skb) > + return -EFAULT; > + > + spin_unlock_irqrestore(&eptdev->queue_lock, flags); > + > + use = min_t(size_t, count, skb->len); > + if (copy_to_user(buf, skb->data, use)) > + use = -EFAULT; > + > + kfree_skb(skb); > + > + return use; > +} > + > +static ssize_t rpmsg_eptdev_write(struct file *filp, const char __user *buf, > + size_t count, loff_t *f_pos) > +{ > + struct rpmsg_eptdev *eptdev = filp->private_data; > + void *kbuf; > + int ret; > + > + kbuf = kzalloc(count, GFP_KERNEL); > + if (!kbuf) > + return -ENOMEM; > + > + if (copy_from_user(kbuf, buf, count)) { > + ret = -EFAULT; > + goto free_kbuf; > + } > + > + if (mutex_lock_interruptible(&eptdev->ept_lock)) { > + ret = -ERESTARTSYS; > + goto free_kbuf; > + } > + > + if (!eptdev->ept) { > + ret = -EPIPE; > + goto unlock_eptdev; > + } > + > + if (filp->f_flags & O_NONBLOCK) > + ret = rpmsg_trysend(eptdev->ept, kbuf, count); > + else > + ret = rpmsg_send(eptdev->ept, kbuf, count); > + > +unlock_eptdev: > + mutex_unlock(&eptdev->ept_lock); > + > +free_kbuf: > + kfree(kbuf); > + return ret; > +} > + > +static const struct file_operations rpmsg_eptdev_fops = { > + .owner = THIS_MODULE, > + .open = rpmsg_eptdev_open, > + .release = rpmsg_eptdev_release, > + .read = rpmsg_eptdev_read, > + .write = rpmsg_eptdev_write, > + .unlocked_ioctl = rpmsg_eptdev_ioctl, > +}; > + > +static ssize_t name_show(struct device *dev, struct device_attribute *attr, > + char *buf) > +{ > + struct rpmsg_eptdev *eptdev = dev_get_drvdata(dev); > + > + return sprintf(buf, "%s\n", eptdev->chinfo.name); > +} > +static DEVICE_ATTR_RO(name); > + > +static ssize_t src_show(struct device *dev, struct device_attribute *attr, > + char *buf) > +{ > + struct rpmsg_eptdev *eptdev = dev_get_drvdata(dev); > + > + return sprintf(buf, "%d\n", eptdev->chinfo.src); > +} > +static DEVICE_ATTR_RO(src); > + > +static ssize_t dst_show(struct device *dev, struct device_attribute *attr, > + char *buf) > +{ > + struct rpmsg_eptdev *eptdev = dev_get_drvdata(dev); > + > + return sprintf(buf, "%d\n", eptdev->chinfo.dst); > +} > +static DEVICE_ATTR_RO(dst); > + > +static struct attribute *rpmsg_eptdev_attrs[] = { > + &dev_attr_name.attr, > + &dev_attr_src.attr, > + &dev_attr_dst.attr, > + NULL > +}; > +ATTRIBUTE_GROUPS(rpmsg_eptdev); > + > +static void rpmsg_eptdev_release_device(struct device *dev) > +{ > + struct rpmsg_eptdev *eptdev = dev_to_eptdev(dev); > + > + ida_simple_remove(&rpmsg_minor_ida, MINOR(eptdev->dev.devt)); > + kfree(eptdev); > +} > + > +static int rpmsg_eptdev_create(struct rpmsg_ctrldev *ctrldev, > + struct rpmsg_channel_info chinfo) > +{ > + struct rpmsg_device *rpdev = ctrldev->rpdev; > + struct rpmsg_eptdev *eptdev; > + struct device *dev; > + int ret; > + int id; > + > + eptdev = kzalloc(sizeof(*eptdev), GFP_KERNEL); > + if (!eptdev) > + return -ENOMEM; > + > + eptdev->rpdev = rpdev; > + eptdev->chinfo = chinfo; > + > + mutex_init(&eptdev->ept_lock); > + spin_lock_init(&eptdev->queue_lock); > + skb_queue_head_init(&eptdev->queue); > + init_waitqueue_head(&eptdev->readq); > + > + id = ida_simple_get(&rpmsg_ept_ida, 0, 0, GFP_KERNEL); > + if (id < 0) { > + kfree(eptdev); > + return id; > + } > + > + dev = &eptdev->dev; > + device_initialize(dev); > + dev->class = rpmsg_class; > + dev->id = id; > + dev->parent = &ctrldev->dev; > + dev->release = rpmsg_eptdev_release_device; > + dev->groups = rpmsg_eptdev_groups; > + dev_set_name(dev, "rpmsg%d", id); > + dev_set_drvdata(dev, eptdev); > + > + ret = rpmsg_cdev_register(dev, &eptdev->cdev, > + &rpmsg_eptdev_fops, &dev->devt); > + if (ret) { > + dev_err(dev, "cdev_add failed: %d\n", ret); > + goto out; > + } > + > + ret = device_add(dev); > + if (ret) { > + dev_err(dev, "device_register failed: %d\n", ret); > + goto out; > + } > + > +out: > + if (ret < 0) > + put_device(dev); > + > + return ret; > +} > + > +static int rpmsg_eptdev_destroy(struct rpmsg_eptdev *eptdev) > +{ > + struct rpmsg_endpoint *ept = eptdev->ept; > + > + mutex_lock(&eptdev->ept_lock); > + eptdev->ept = NULL; > + mutex_unlock(&eptdev->ept_lock); > + > + rpmsg_destroy_ept(ept); > + > + /* wake up any blocking processes */ > + wake_up_interruptible(&eptdev->readq); > + > + cdev_del(&eptdev->cdev); > + device_del(&eptdev->dev); > + put_device(&eptdev->dev); > + > + return 0; > +} > + > +static int rpmsg_ctrldev_open(struct inode *inode, struct file *filp) > +{ > + struct rpmsg_ctrldev *ctrldev = cdev_to_ctrldev(inode->i_cdev); > + > + get_device(&ctrldev->rpdev->dev); > + filp->private_data = ctrldev; > + > + return 0; > +} > + > +static int rpmsg_ctrldev_release(struct inode *inode, struct file *filp) > +{ > + struct rpmsg_ctrldev *ctrldev = cdev_to_ctrldev(inode->i_cdev); > + > + put_device(&ctrldev->rpdev->dev); > + > + return 0; > +} > + > +static long rpmsg_ctrldev_ioctl(struct file *fp, unsigned int cmd, > + unsigned long arg) > +{ > + struct rpmsg_ctrldev *ctrldev = fp->private_data; > + void __user *argp = (void __user *)arg; > + struct rpmsg_endpoint_info eptinfo; > + struct rpmsg_channel_info chinfo; > + > + if (cmd != RPMSG_CREATE_EPT_IOCTL) > + return -EINVAL; > + > + if (copy_from_user(&eptinfo, argp, sizeof(eptinfo))) > + return -EFAULT; > + > + memcpy(chinfo.name, eptinfo.name, RPMSG_NAME_SIZE); > + chinfo.name[RPMSG_NAME_SIZE-1] = '\0'; > + chinfo.src = eptinfo.src; > + chinfo.dst = eptinfo.dst; > + > + return rpmsg_eptdev_create(ctrldev, chinfo); > +}; > + > +static const struct file_operations rpmsg_ctrldev_fops = { > + .owner = THIS_MODULE, > + .open = rpmsg_ctrldev_open, > + .release = rpmsg_ctrldev_release, > + .unlocked_ioctl = rpmsg_ctrldev_ioctl, > +}; > + > +static void rpmsg_chrdev_release_device(struct device *dev) > +{ > + struct rpmsg_ctrldev *ctrldev = dev_to_ctrldev(dev); > + > + ida_simple_remove(&rpmsg_ctrl_ida, MINOR(dev->devt)); > + cdev_del(&ctrldev->cdev); > + kfree(ctrldev); > +} > + > +static int rpmsg_chrdev_probe(struct rpmsg_device *rpdev) > +{ > + struct rpmsg_ctrldev *ctrldev; > + struct device *dev; > + int ret; > + int id; > + > + ctrldev = kzalloc(sizeof(*ctrldev), GFP_KERNEL); > + if (!ctrldev) > + return -ENOMEM; > + > + dev = &ctrldev->dev; > + > + ctrldev->rpdev = rpdev; > + > + id = ida_simple_get(&rpmsg_ctrl_ida, 0, 0, GFP_KERNEL); > + if (id < 0) { > + kfree(ctrldev); > + return id; > + } > + > + device_initialize(dev); > + dev->parent = &rpdev->dev; > + dev->class = rpmsg_class; > + dev->release = rpmsg_chrdev_release_device; > + dev_set_name(&ctrldev->dev, "rpmsg_ctrl%d", id); > + > + ret = rpmsg_cdev_register(dev, &ctrldev->cdev, > + &rpmsg_ctrldev_fops, &dev->devt); > + if (ret < 0) { > + put_device(dev); > + return ret; > + } > + > + ret = device_add(dev); > + if (ret) { > + dev_err(&rpdev->dev, "device_register failed: %d\n", ret); > + put_device(dev); > + } > + > + dev_set_drvdata(&rpdev->dev, ctrldev); > + > + return ret; > +} > + > +static int _rpmsg_eptdev_destroy(struct device *dev, void *data) > +{ > + struct rpmsg_eptdev *eptdev = dev_to_eptdev(dev); > + > + return rpmsg_eptdev_destroy(eptdev); > +} > + > +static void rpmsg_chrdev_remove(struct rpmsg_device *rpdev) > +{ > + struct rpmsg_ctrldev *ctrldev = dev_get_drvdata(&rpdev->dev); > + int ret; > + > + /* Destroy all endpoints */ > + ret = device_for_each_child(&ctrldev->dev, NULL, _rpmsg_eptdev_destroy); > + if (ret) > + dev_warn(&rpdev->dev, "failed to nuke endpoints: %d\n", ret); > + > + device_del(&ctrldev->dev); > + put_device(&ctrldev->dev); > +} > + > +static struct rpmsg_driver rpmsg_chrdev_driver = { > + .probe = rpmsg_chrdev_probe, > + .remove = rpmsg_chrdev_remove, > + .drv = { > + .name = "rpmsg_chrdev", > + }, > +}; > + > +/** > + * rpmsg_chrdev_register_device() - register chrdev device based on rpdev > + * @rpdev: prepared rpdev to be used for creating endpoints > + * > + * This function wraps rpmsg_register_device() preparing the rpdev for use as > + * basis for the rpmsg chrdev. > + */ > +int rpmsg_chrdev_register_device(struct rpmsg_device *rpdev) > +{ > + strcpy(rpdev->id.name, "rpmsg_chrdev"); > + rpdev->driver_override = "rpmsg_chrdev"; > + > + return rpmsg_register_device(rpdev); > +} > +EXPORT_SYMBOL(rpmsg_chrdev_register_device); > + > +static int rpmsg_char_init(void) > +{ > + int ret; > + > + ret = alloc_chrdev_region(&rpmsg_major, 0, RPMSG_DEV_MAX, "rpmsg"); > + if (ret < 0) { > + pr_err("rpmsg: failed to allocate char dev region\n"); > + return ret; > + } > + > + rpmsg_class = class_create(THIS_MODULE, "rpmsg"); > + if (IS_ERR(rpmsg_class)) { > + pr_err("failed to create rpmsg class\n"); > + ret = PTR_ERR(rpmsg_class); > + goto unregister_chrdev; > + } > + > + ret = register_rpmsg_driver(&rpmsg_chrdev_driver); > + if (ret < 0) { > + pr_err("rpmsgchr: failed to register rpmsg driver\n"); > + goto destroy_class; > + } > + > + return 0; > + > +destroy_class: > + class_destroy(rpmsg_class); > + > +unregister_chrdev: > + unregister_chrdev_region(rpmsg_major, RPMSG_DEV_MAX); > + > + return ret; > +} > +postcore_initcall(rpmsg_char_init); > + > +static void rpmsg_chrdev_exit(void) > +{ > + unregister_rpmsg_driver(&rpmsg_chrdev_driver); > + unregister_chrdev_region(rpmsg_major, RPMSG_DEV_MAX); > +} > +module_exit(rpmsg_chrdev_exit); > diff --git a/drivers/rpmsg/rpmsg_internal.h b/drivers/rpmsg/rpmsg_internal.h > index 8075a20f919b..53d300eacc1c 100644 > --- a/drivers/rpmsg/rpmsg_internal.h > +++ b/drivers/rpmsg/rpmsg_internal.h > @@ -79,4 +79,6 @@ int rpmsg_unregister_device(struct device *parent, > struct device *rpmsg_find_device(struct device *parent, > struct rpmsg_channel_info *chinfo); > > +int rpmsg_chrdev_register_device(struct rpmsg_device *rpdev); > + > #endif > diff --git a/include/uapi/linux/rpmsg.h b/include/uapi/linux/rpmsg.h > new file mode 100644 > index 000000000000..dedc226e0d3f > --- /dev/null > +++ b/include/uapi/linux/rpmsg.h > @@ -0,0 +1,35 @@ > +/* > + * Copyright (c) 2016, Linaro Ltd. > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License version 2 and > + * only version 2 as published by the Free Software Foundation. > + * > + * This program is distributed in the hope that it will be useful, > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > + * GNU General Public License for more details. > + */ > + > +#ifndef _UAPI_RPMSG_H_ > +#define _UAPI_RPMSG_H_ > + > +#include <linux/ioctl.h> > +#include <linux/types.h> > + > +/** > + * struct rpmsg_endpoint_info - endpoint info representation > + * @name: name of service > + * @src: local address > + * @dst: destination address > + */ > +struct rpmsg_endpoint_info { > + char name[32]; > + __u32 src; > + __u32 dst; > +}; > + > +#define RPMSG_CREATE_EPT_IOCTL _IOW(0xb5, 0x1, struct rpmsg_endpoint_info) > +#define RPMSG_DESTROY_EPT_IOCTL _IO(0xb5, 0x2) > + > +#endif >
On Tue 11 Oct 00:46 PDT 2016, loic pallardy wrote: > On 10/08/2016 06:23 AM, Bjorn Andersson wrote: [..] > >diff --git a/drivers/rpmsg/Makefile b/drivers/rpmsg/Makefile > >index ae9c9132cf76..5daf1209b77d 100644 > >--- a/drivers/rpmsg/Makefile > >+++ b/drivers/rpmsg/Makefile > >@@ -1,3 +1,3 @@ > >-obj-$(CONFIG_RPMSG) += rpmsg_core.o > >+obj-$(CONFIG_RPMSG) += rpmsg_core.o rpmsg_char.o > Hi Bjorn, > > Could you please create a dedicated Kconfig entry for this new interface? > This should be an option like i2C_dev. > No problem, I'll do that. Regards, Bjorn
diff --git a/Documentation/ioctl/ioctl-number.txt b/Documentation/ioctl/ioctl-number.txt index 81c7f2bb7daf..08244bea5048 100644 --- a/Documentation/ioctl/ioctl-number.txt +++ b/Documentation/ioctl/ioctl-number.txt @@ -321,6 +321,7 @@ Code Seq#(hex) Include File Comments 0xB1 00-1F PPPoX <mailto:mostrows@styx.uwaterloo.ca> 0xB3 00 linux/mmc/ioctl.h 0xB4 00-0F linux/gpio.h <mailto:linux-gpio@vger.kernel.org> +0xB5 00-0F uapi/linux/rpmsg.h <mailto:linux-remoteproc@vger.kernel.org> 0xC0 00-0F linux/usb/iowarrior.h 0xCA 00-0F uapi/misc/cxl.h 0xCA 80-8F uapi/scsi/cxlflash_ioctl.h diff --git a/drivers/rpmsg/Makefile b/drivers/rpmsg/Makefile index ae9c9132cf76..5daf1209b77d 100644 --- a/drivers/rpmsg/Makefile +++ b/drivers/rpmsg/Makefile @@ -1,3 +1,3 @@ -obj-$(CONFIG_RPMSG) += rpmsg_core.o +obj-$(CONFIG_RPMSG) += rpmsg_core.o rpmsg_char.o obj-$(CONFIG_RPMSG_QCOM_SMD) += qcom_smd.o obj-$(CONFIG_RPMSG_VIRTIO) += virtio_rpmsg_bus.o diff --git a/drivers/rpmsg/rpmsg_char.c b/drivers/rpmsg/rpmsg_char.c new file mode 100644 index 000000000000..a398a63e8d44 --- /dev/null +++ b/drivers/rpmsg/rpmsg_char.c @@ -0,0 +1,576 @@ +/* + * Copyright (c) 2016, Linaro Ltd. + * Copyright (c) 2012, Michal Simek <monstr@monstr.eu> + * Copyright (c) 2012, PetaLogix + * Copyright (c) 2011, Texas Instruments, Inc. + * Copyright (c) 2011, Google, Inc. + * + * Based on rpmsg performance statistics driver by Michal Simek, which in turn + * was based on TI & Google OMX rpmsg driver. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 and + * only version 2 as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ +#include <linux/cdev.h> +#include <linux/device.h> +#include <linux/fs.h> +#include <linux/idr.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/rpmsg.h> +#include <linux/skbuff.h> +#include <linux/slab.h> +#include <linux/uaccess.h> +#include <uapi/linux/rpmsg.h> + +#include "rpmsg_internal.h" + +#define RPMSG_DEV_MAX 256 + +static dev_t rpmsg_major; +static struct class *rpmsg_class; + +static DEFINE_IDA(rpmsg_ctrl_ida); +static DEFINE_IDA(rpmsg_ept_ida); +static DEFINE_IDA(rpmsg_minor_ida); + +#define dev_to_eptdev(dev) container_of(dev, struct rpmsg_eptdev, dev) +#define cdev_to_eptdev(i_cdev) container_of(i_cdev, struct rpmsg_eptdev, cdev) + +#define dev_to_ctrldev(dev) container_of(dev, struct rpmsg_ctrldev, dev) +#define cdev_to_ctrldev(i_cdev) container_of(i_cdev, struct rpmsg_ctrldev, cdev) + +struct rpmsg_ctrldev { + struct rpmsg_device *rpdev; + struct cdev cdev; + struct device dev; +}; + +struct rpmsg_eptdev { + struct device dev; + struct cdev cdev; + + struct rpmsg_device *rpdev; + struct rpmsg_channel_info chinfo; + + struct mutex ept_lock; + struct rpmsg_endpoint *ept; + + spinlock_t queue_lock; + struct sk_buff_head queue; + wait_queue_head_t readq; +}; + +static int rpmsg_eptdev_destroy(struct rpmsg_eptdev *eptdev); + + +static int rpmsg_cdev_register(struct device *dev, + struct cdev *cdev, + const struct file_operations *fops, + dev_t *assigned_devt) +{ + dev_t devt; + int ret; + + ret = ida_simple_get(&rpmsg_minor_ida, 0, 0, GFP_KERNEL); + if (ret < 0) + return ret; + + devt = MKDEV(MAJOR(rpmsg_major), ret); + + cdev_init(cdev, fops); + cdev->owner = THIS_MODULE; + ret = cdev_add(cdev, devt, 1); + if (ret < 0) { + dev_err(dev, "cdev_add failed: %d\n", ret); + ida_simple_remove(&rpmsg_minor_ida, MINOR(devt)); + return ret; + } + + *assigned_devt = devt; + return 0; +} + +static int rpmsg_ept_cb(struct rpmsg_device *rpdev, void *buf, int len, + void *priv, u32 addr) +{ + struct rpmsg_eptdev *eptdev = priv; + struct sk_buff *skb; + + skb = alloc_skb(len, GFP_ATOMIC); + if (!skb) + return -ENOMEM; + + memcpy(skb_put(skb, len), buf, len); + + spin_lock(&eptdev->queue_lock); + skb_queue_tail(&eptdev->queue, skb); + spin_unlock(&eptdev->queue_lock); + + /* wake up any blocking processes, waiting for new data */ + wake_up_interruptible(&eptdev->readq); + + return 0; +} + +static int rpmsg_eptdev_open(struct inode *inode, struct file *filp) +{ + struct rpmsg_eptdev *eptdev = cdev_to_eptdev(inode->i_cdev); + struct rpmsg_endpoint *ept; + struct rpmsg_device *rpdev = eptdev->rpdev; + struct device *dev = &eptdev->dev; + + get_device(dev); + + ept = rpmsg_create_ept(rpdev, rpmsg_ept_cb, eptdev, eptdev->chinfo); + if (!ept) { + dev_err(dev, "failed to open %s\n", eptdev->chinfo.name); + put_device(dev); + return -EINVAL; + } + + eptdev->ept = ept; + filp->private_data = eptdev; + + return 0; +} + +static int rpmsg_eptdev_release(struct inode *inode, struct file *filp) +{ + struct rpmsg_eptdev *eptdev = cdev_to_eptdev(inode->i_cdev); + struct device *dev = &eptdev->dev; + struct sk_buff *skb; + + /* Close the endpoint, if it's not already destroyed by the parent */ + if (eptdev->ept) + rpmsg_destroy_ept(eptdev->ept); + + /* Discard all SKBs */ + while (!skb_queue_empty(&eptdev->queue)) { + skb = skb_dequeue(&eptdev->queue); + kfree_skb(skb); + } + + put_device(dev); + + return 0; +} + +static long rpmsg_eptdev_ioctl(struct file *fp, unsigned int cmd, + unsigned long arg) +{ + struct rpmsg_eptdev *eptdev = fp->private_data; + + if (cmd != RPMSG_DESTROY_EPT_IOCTL) + return -EINVAL; + + return rpmsg_eptdev_destroy(eptdev); +} + +static ssize_t rpmsg_eptdev_read(struct file *filp, char __user *buf, + size_t count, loff_t *f_pos) +{ + struct rpmsg_eptdev *eptdev = filp->private_data; + unsigned long flags; + struct sk_buff *skb; + int use; + + spin_lock_irqsave(&eptdev->queue_lock, flags); + + /* Wait for data in the queue */ + if (skb_queue_empty(&eptdev->queue)) { + spin_unlock_irqrestore(&eptdev->queue_lock, flags); + + if (filp->f_flags & O_NONBLOCK) + return -EAGAIN; + + /* Wait until we get data or the endpoint goes away */ + if (wait_event_interruptible(eptdev->readq, + !skb_queue_empty(&eptdev->queue) || + !eptdev->ept)) + return -ERESTARTSYS; + + /* We lost the endpoint while waiting */ + if (!eptdev->ept) + return -EPIPE; + + spin_lock_irqsave(&eptdev->queue_lock, flags); + } + + skb = skb_dequeue(&eptdev->queue); + if (!skb) + return -EFAULT; + + spin_unlock_irqrestore(&eptdev->queue_lock, flags); + + use = min_t(size_t, count, skb->len); + if (copy_to_user(buf, skb->data, use)) + use = -EFAULT; + + kfree_skb(skb); + + return use; +} + +static ssize_t rpmsg_eptdev_write(struct file *filp, const char __user *buf, + size_t count, loff_t *f_pos) +{ + struct rpmsg_eptdev *eptdev = filp->private_data; + void *kbuf; + int ret; + + kbuf = kzalloc(count, GFP_KERNEL); + if (!kbuf) + return -ENOMEM; + + if (copy_from_user(kbuf, buf, count)) { + ret = -EFAULT; + goto free_kbuf; + } + + if (mutex_lock_interruptible(&eptdev->ept_lock)) { + ret = -ERESTARTSYS; + goto free_kbuf; + } + + if (!eptdev->ept) { + ret = -EPIPE; + goto unlock_eptdev; + } + + if (filp->f_flags & O_NONBLOCK) + ret = rpmsg_trysend(eptdev->ept, kbuf, count); + else + ret = rpmsg_send(eptdev->ept, kbuf, count); + +unlock_eptdev: + mutex_unlock(&eptdev->ept_lock); + +free_kbuf: + kfree(kbuf); + return ret; +} + +static const struct file_operations rpmsg_eptdev_fops = { + .owner = THIS_MODULE, + .open = rpmsg_eptdev_open, + .release = rpmsg_eptdev_release, + .read = rpmsg_eptdev_read, + .write = rpmsg_eptdev_write, + .unlocked_ioctl = rpmsg_eptdev_ioctl, +}; + +static ssize_t name_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct rpmsg_eptdev *eptdev = dev_get_drvdata(dev); + + return sprintf(buf, "%s\n", eptdev->chinfo.name); +} +static DEVICE_ATTR_RO(name); + +static ssize_t src_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct rpmsg_eptdev *eptdev = dev_get_drvdata(dev); + + return sprintf(buf, "%d\n", eptdev->chinfo.src); +} +static DEVICE_ATTR_RO(src); + +static ssize_t dst_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct rpmsg_eptdev *eptdev = dev_get_drvdata(dev); + + return sprintf(buf, "%d\n", eptdev->chinfo.dst); +} +static DEVICE_ATTR_RO(dst); + +static struct attribute *rpmsg_eptdev_attrs[] = { + &dev_attr_name.attr, + &dev_attr_src.attr, + &dev_attr_dst.attr, + NULL +}; +ATTRIBUTE_GROUPS(rpmsg_eptdev); + +static void rpmsg_eptdev_release_device(struct device *dev) +{ + struct rpmsg_eptdev *eptdev = dev_to_eptdev(dev); + + ida_simple_remove(&rpmsg_minor_ida, MINOR(eptdev->dev.devt)); + kfree(eptdev); +} + +static int rpmsg_eptdev_create(struct rpmsg_ctrldev *ctrldev, + struct rpmsg_channel_info chinfo) +{ + struct rpmsg_device *rpdev = ctrldev->rpdev; + struct rpmsg_eptdev *eptdev; + struct device *dev; + int ret; + int id; + + eptdev = kzalloc(sizeof(*eptdev), GFP_KERNEL); + if (!eptdev) + return -ENOMEM; + + eptdev->rpdev = rpdev; + eptdev->chinfo = chinfo; + + mutex_init(&eptdev->ept_lock); + spin_lock_init(&eptdev->queue_lock); + skb_queue_head_init(&eptdev->queue); + init_waitqueue_head(&eptdev->readq); + + id = ida_simple_get(&rpmsg_ept_ida, 0, 0, GFP_KERNEL); + if (id < 0) { + kfree(eptdev); + return id; + } + + dev = &eptdev->dev; + device_initialize(dev); + dev->class = rpmsg_class; + dev->id = id; + dev->parent = &ctrldev->dev; + dev->release = rpmsg_eptdev_release_device; + dev->groups = rpmsg_eptdev_groups; + dev_set_name(dev, "rpmsg%d", id); + dev_set_drvdata(dev, eptdev); + + ret = rpmsg_cdev_register(dev, &eptdev->cdev, + &rpmsg_eptdev_fops, &dev->devt); + if (ret) { + dev_err(dev, "cdev_add failed: %d\n", ret); + goto out; + } + + ret = device_add(dev); + if (ret) { + dev_err(dev, "device_register failed: %d\n", ret); + goto out; + } + +out: + if (ret < 0) + put_device(dev); + + return ret; +} + +static int rpmsg_eptdev_destroy(struct rpmsg_eptdev *eptdev) +{ + struct rpmsg_endpoint *ept = eptdev->ept; + + mutex_lock(&eptdev->ept_lock); + eptdev->ept = NULL; + mutex_unlock(&eptdev->ept_lock); + + rpmsg_destroy_ept(ept); + + /* wake up any blocking processes */ + wake_up_interruptible(&eptdev->readq); + + cdev_del(&eptdev->cdev); + device_del(&eptdev->dev); + put_device(&eptdev->dev); + + return 0; +} + +static int rpmsg_ctrldev_open(struct inode *inode, struct file *filp) +{ + struct rpmsg_ctrldev *ctrldev = cdev_to_ctrldev(inode->i_cdev); + + get_device(&ctrldev->rpdev->dev); + filp->private_data = ctrldev; + + return 0; +} + +static int rpmsg_ctrldev_release(struct inode *inode, struct file *filp) +{ + struct rpmsg_ctrldev *ctrldev = cdev_to_ctrldev(inode->i_cdev); + + put_device(&ctrldev->rpdev->dev); + + return 0; +} + +static long rpmsg_ctrldev_ioctl(struct file *fp, unsigned int cmd, + unsigned long arg) +{ + struct rpmsg_ctrldev *ctrldev = fp->private_data; + void __user *argp = (void __user *)arg; + struct rpmsg_endpoint_info eptinfo; + struct rpmsg_channel_info chinfo; + + if (cmd != RPMSG_CREATE_EPT_IOCTL) + return -EINVAL; + + if (copy_from_user(&eptinfo, argp, sizeof(eptinfo))) + return -EFAULT; + + memcpy(chinfo.name, eptinfo.name, RPMSG_NAME_SIZE); + chinfo.name[RPMSG_NAME_SIZE-1] = '\0'; + chinfo.src = eptinfo.src; + chinfo.dst = eptinfo.dst; + + return rpmsg_eptdev_create(ctrldev, chinfo); +}; + +static const struct file_operations rpmsg_ctrldev_fops = { + .owner = THIS_MODULE, + .open = rpmsg_ctrldev_open, + .release = rpmsg_ctrldev_release, + .unlocked_ioctl = rpmsg_ctrldev_ioctl, +}; + +static void rpmsg_chrdev_release_device(struct device *dev) +{ + struct rpmsg_ctrldev *ctrldev = dev_to_ctrldev(dev); + + ida_simple_remove(&rpmsg_ctrl_ida, MINOR(dev->devt)); + cdev_del(&ctrldev->cdev); + kfree(ctrldev); +} + +static int rpmsg_chrdev_probe(struct rpmsg_device *rpdev) +{ + struct rpmsg_ctrldev *ctrldev; + struct device *dev; + int ret; + int id; + + ctrldev = kzalloc(sizeof(*ctrldev), GFP_KERNEL); + if (!ctrldev) + return -ENOMEM; + + dev = &ctrldev->dev; + + ctrldev->rpdev = rpdev; + + id = ida_simple_get(&rpmsg_ctrl_ida, 0, 0, GFP_KERNEL); + if (id < 0) { + kfree(ctrldev); + return id; + } + + device_initialize(dev); + dev->parent = &rpdev->dev; + dev->class = rpmsg_class; + dev->release = rpmsg_chrdev_release_device; + dev_set_name(&ctrldev->dev, "rpmsg_ctrl%d", id); + + ret = rpmsg_cdev_register(dev, &ctrldev->cdev, + &rpmsg_ctrldev_fops, &dev->devt); + if (ret < 0) { + put_device(dev); + return ret; + } + + ret = device_add(dev); + if (ret) { + dev_err(&rpdev->dev, "device_register failed: %d\n", ret); + put_device(dev); + } + + dev_set_drvdata(&rpdev->dev, ctrldev); + + return ret; +} + +static int _rpmsg_eptdev_destroy(struct device *dev, void *data) +{ + struct rpmsg_eptdev *eptdev = dev_to_eptdev(dev); + + return rpmsg_eptdev_destroy(eptdev); +} + +static void rpmsg_chrdev_remove(struct rpmsg_device *rpdev) +{ + struct rpmsg_ctrldev *ctrldev = dev_get_drvdata(&rpdev->dev); + int ret; + + /* Destroy all endpoints */ + ret = device_for_each_child(&ctrldev->dev, NULL, _rpmsg_eptdev_destroy); + if (ret) + dev_warn(&rpdev->dev, "failed to nuke endpoints: %d\n", ret); + + device_del(&ctrldev->dev); + put_device(&ctrldev->dev); +} + +static struct rpmsg_driver rpmsg_chrdev_driver = { + .probe = rpmsg_chrdev_probe, + .remove = rpmsg_chrdev_remove, + .drv = { + .name = "rpmsg_chrdev", + }, +}; + +/** + * rpmsg_chrdev_register_device() - register chrdev device based on rpdev + * @rpdev: prepared rpdev to be used for creating endpoints + * + * This function wraps rpmsg_register_device() preparing the rpdev for use as + * basis for the rpmsg chrdev. + */ +int rpmsg_chrdev_register_device(struct rpmsg_device *rpdev) +{ + strcpy(rpdev->id.name, "rpmsg_chrdev"); + rpdev->driver_override = "rpmsg_chrdev"; + + return rpmsg_register_device(rpdev); +} +EXPORT_SYMBOL(rpmsg_chrdev_register_device); + +static int rpmsg_char_init(void) +{ + int ret; + + ret = alloc_chrdev_region(&rpmsg_major, 0, RPMSG_DEV_MAX, "rpmsg"); + if (ret < 0) { + pr_err("rpmsg: failed to allocate char dev region\n"); + return ret; + } + + rpmsg_class = class_create(THIS_MODULE, "rpmsg"); + if (IS_ERR(rpmsg_class)) { + pr_err("failed to create rpmsg class\n"); + ret = PTR_ERR(rpmsg_class); + goto unregister_chrdev; + } + + ret = register_rpmsg_driver(&rpmsg_chrdev_driver); + if (ret < 0) { + pr_err("rpmsgchr: failed to register rpmsg driver\n"); + goto destroy_class; + } + + return 0; + +destroy_class: + class_destroy(rpmsg_class); + +unregister_chrdev: + unregister_chrdev_region(rpmsg_major, RPMSG_DEV_MAX); + + return ret; +} +postcore_initcall(rpmsg_char_init); + +static void rpmsg_chrdev_exit(void) +{ + unregister_rpmsg_driver(&rpmsg_chrdev_driver); + unregister_chrdev_region(rpmsg_major, RPMSG_DEV_MAX); +} +module_exit(rpmsg_chrdev_exit); diff --git a/drivers/rpmsg/rpmsg_internal.h b/drivers/rpmsg/rpmsg_internal.h index 8075a20f919b..53d300eacc1c 100644 --- a/drivers/rpmsg/rpmsg_internal.h +++ b/drivers/rpmsg/rpmsg_internal.h @@ -79,4 +79,6 @@ int rpmsg_unregister_device(struct device *parent, struct device *rpmsg_find_device(struct device *parent, struct rpmsg_channel_info *chinfo); +int rpmsg_chrdev_register_device(struct rpmsg_device *rpdev); + #endif diff --git a/include/uapi/linux/rpmsg.h b/include/uapi/linux/rpmsg.h new file mode 100644 index 000000000000..dedc226e0d3f --- /dev/null +++ b/include/uapi/linux/rpmsg.h @@ -0,0 +1,35 @@ +/* + * Copyright (c) 2016, Linaro Ltd. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 and + * only version 2 as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#ifndef _UAPI_RPMSG_H_ +#define _UAPI_RPMSG_H_ + +#include <linux/ioctl.h> +#include <linux/types.h> + +/** + * struct rpmsg_endpoint_info - endpoint info representation + * @name: name of service + * @src: local address + * @dst: destination address + */ +struct rpmsg_endpoint_info { + char name[32]; + __u32 src; + __u32 dst; +}; + +#define RPMSG_CREATE_EPT_IOCTL _IOW(0xb5, 0x1, struct rpmsg_endpoint_info) +#define RPMSG_DESTROY_EPT_IOCTL _IO(0xb5, 0x2) + +#endif
This driver allows rpmsg instances to expose access to rpmsg endpoints to user space processes. It provides a control interface, allowing userspace to export endpoints and an endpoint interface for each exposed endpoint. The implementation is based on prior art by Texas Instrument, Google, PetaLogix and was derived from a FreeRTOS performance statistics driver written by Michal Simek. The control interface provides a "create endpoint" ioctl, which is fed a name, source and destination address. The three values are used to create the endpoint, in a backend-specific way, and a rpmsg endpoint device is created - with the three parameters are available in sysfs for udev usage. E.g. to create an endpoint device for one of the Qualcomm SMD channel related to DIAG one would issue: struct rpmsg_endpoint_info info = { "DIAG_CNTL", 0, 0 }; int fd = open("/dev/rpmsg_ctrl0", O_RDWR); ioctl(fd, RPMSG_CREATE_EPT_IOCTL, &info); Each created endpoint device shows up as an individual character device in /dev, allowing permission to be controlled on a per-endpoint basis. The rpmsg endpoint will be created and destroyed following the opening and closing of the endpoint device, allowing rpmsg backends to open and close the physical channel, if supported by the wire protocol. Cc: Marek Novak <marek.novak@nxp.com> Cc: Matteo Sartori <matteo.sartori@t3lab.it> Cc: Michal Simek <monstr@monstr.eu> Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org> --- Documentation/ioctl/ioctl-number.txt | 1 + drivers/rpmsg/Makefile | 2 +- drivers/rpmsg/rpmsg_char.c | 576 +++++++++++++++++++++++++++++++++++ drivers/rpmsg/rpmsg_internal.h | 2 + include/uapi/linux/rpmsg.h | 35 +++ 5 files changed, 615 insertions(+), 1 deletion(-) create mode 100644 drivers/rpmsg/rpmsg_char.c create mode 100644 include/uapi/linux/rpmsg.h