Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S936136AbZDIQim (ORCPT ); Thu, 9 Apr 2009 12:38:42 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S935573AbZDIQa1 (ORCPT ); Thu, 9 Apr 2009 12:30:27 -0400 Received: from victor.provo.novell.com ([137.65.250.26]:38177 "EHLO victor.provo.novell.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S935571AbZDIQaO (ORCPT ); Thu, 9 Apr 2009 12:30:14 -0400 From: Gregory Haskins Subject: [RFC PATCH v2 18/19] vbus: add a userspace connector To: linux-kernel@vger.kernel.org Cc: agraf@suse.de, pmullaney@novell.com, pmorreale@novell.com, anthony@codemonkey.ws, rusty@rustcorp.com.au, netdev@vger.kernel.org, kvm@vger.kernel.org, avi@redhat.com, bhutchings@solarflare.com, andi@firstfloor.org, gregkh@suse.de, herber@gondor.apana.org.au, chrisw@sous-sol.org, shemminger@vyatta.com Date: Thu, 09 Apr 2009 12:32:16 -0400 Message-ID: <20090409163215.32740.10903.stgit@dev.haskins.net> In-Reply-To: <20090409155200.32740.19358.stgit@dev.haskins.net> References: <20090409155200.32740.19358.stgit@dev.haskins.net> User-Agent: StGIT/0.14.3 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 14863 Lines: 630 This allows userspace applications to access vbus devices Signed-off-by: Gregory Haskins --- include/linux/vbus.h | 4 include/linux/vbus_client.h | 2 include/linux/vbus_userspace.h | 48 ++++ kernel/vbus/Kconfig | 10 + kernel/vbus/Makefile | 2 kernel/vbus/userspace-client.c | 485 ++++++++++++++++++++++++++++++++++++++++ 6 files changed, 550 insertions(+), 1 deletions(-) create mode 100644 include/linux/vbus_userspace.h create mode 100644 kernel/vbus/userspace-client.c diff --git a/include/linux/vbus.h b/include/linux/vbus.h index 04db4ff..f967e59 100644 --- a/include/linux/vbus.h +++ b/include/linux/vbus.h @@ -23,6 +23,8 @@ #ifndef _LINUX_VBUS_H #define _LINUX_VBUS_H +#ifdef __KERNEL__ + #ifdef CONFIG_VBUS #include @@ -159,4 +161,6 @@ int vbus_notifier_unregister(struct vbus *vbus, struct notifier_block *nb); #endif /* CONFIG_VBUS */ +#endif /* __KERNEL__ */ + #endif /* _LINUX_VBUS_H */ diff --git a/include/linux/vbus_client.h b/include/linux/vbus_client.h index 62dab78..4c82822 100644 --- a/include/linux/vbus_client.h +++ b/include/linux/vbus_client.h @@ -35,7 +35,7 @@ #ifndef _LINUX_VBUS_CLIENT_H #define _LINUX_VBUS_CLIENT_H -#include +#include #include struct vbus_deviceopen { diff --git a/include/linux/vbus_userspace.h b/include/linux/vbus_userspace.h new file mode 100644 index 0000000..0b78686 --- /dev/null +++ b/include/linux/vbus_userspace.h @@ -0,0 +1,48 @@ +/* + * Copyright 2009 Novell. All Rights Reserved. + * + * Virtual-Bus + * + * Author: + * Gregory Haskins + * + * This file is free software; you can redistribute it and/or modify + * it under the terms of version 2 of the GNU General Public License + * 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. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software Foundation, + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA. + */ + +#ifndef _LINUX_VBUS_USERSPACE_H +#define _LINUX_VBUS_USERSPACE_H + +#include +#include +#include + +#define VBUS_USERSPACE_ABI_MAGIC 0x4fa23b58 +#define VBUS_USERSPACE_ABI_VERSION 1 + +struct vbus_userspace_busopen { + __u32 magic; + __u32 version; + __u64 capabilities; +}; + +#define VBUS_IOCTL_MAGIC 'v' + +#define VBUS_BUSOPEN _IOWR(VBUS_IOCTL_MAGIC, 0x00, struct vbus_userspace_busopen) +#define VBUS_DEVICEOPEN _IOWR(VBUS_IOCTL_MAGIC, 0x01, struct vbus_deviceopen) +#define VBUS_DEVICECLOSE _IOWR(VBUS_IOCTL_MAGIC, 0x02, __u64) +#define VBUS_DEVICECALL _IOWR(VBUS_IOCTL_MAGIC, 0x03, struct vbus_devicecall) +#define VBUS_DEVICESHM _IOWR(VBUS_IOCTL_MAGIC, 0x04, struct vbus_deviceshm) +#define VBUS_SHMSIGNAL _IOWR(VBUS_IOCTL_MAGIC, 0x05, __u64) + +#endif /* _LINUX_VBUS_USERSPACE_H */ diff --git a/kernel/vbus/Kconfig b/kernel/vbus/Kconfig index 3ce0adc..b894dd1 100644 --- a/kernel/vbus/Kconfig +++ b/kernel/vbus/Kconfig @@ -25,6 +25,16 @@ config VBUS_DEVICES source "drivers/vbus/devices/Kconfig" +config VBUS_USERSPACE + tristate "Virtual-Bus userspace client support" + depends on VBUS + default y + help + Provides facilities for userspace applications to access virtual- + bus objects. + + If unsure, say N + config VBUS_DRIVERS tristate "VBUS Driver support" select IOQ diff --git a/kernel/vbus/Makefile b/kernel/vbus/Makefile index 45f6503..61d0371 100644 --- a/kernel/vbus/Makefile +++ b/kernel/vbus/Makefile @@ -4,3 +4,5 @@ obj-$(CONFIG_VBUS) += shm-ioq.o vbus-proxy-objs += proxy.o obj-$(CONFIG_VBUS_DRIVERS) += vbus-proxy.o +vbus-userspace-objs += userspace-client.o +obj-$(CONFIG_VBUS_USERSPACE) += vbus-userspace.o diff --git a/kernel/vbus/userspace-client.c b/kernel/vbus/userspace-client.c new file mode 100644 index 0000000..b2fe447 --- /dev/null +++ b/kernel/vbus/userspace-client.c @@ -0,0 +1,485 @@ +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include + +#include "vbus.h" + +MODULE_AUTHOR("Gregory Haskins"); +MODULE_LICENSE("GPL"); + +struct userspace_chardev; + +struct userspace_signal { + struct userspace_chardev *cd; + struct vbus_shm *shm; + struct shm_signal signal; + struct list_head list; + int signaled; + int prio; + u64 cookie; +}; + +struct userspace_shm { + struct vbus_shm shm; +}; + +struct userspace_chardev { + spinlock_t lock; + int opened; + struct vbus_memctx *ctx; + struct vbus_client *client; + struct list_head signal_list; + wait_queue_head_t wq; + struct vbus *vbus; +}; + +static long +_busopen(struct userspace_chardev *cd, struct vbus_userspace_busopen *args) +{ + if (cd->opened) + return -EINVAL; + + if (args->magic != VBUS_USERSPACE_ABI_MAGIC) + return -EINVAL; + + if (args->version != VBUS_USERSPACE_ABI_VERSION) + return -EINVAL; + + /* + * We have no extended capabilities yet, so we dont care if they set + * any option bits. Just clear them all. + */ + args->capabilities = 0; + + cd->opened = 1; + + return 0; +} + +static long +_deviceopen(struct userspace_chardev *cd, struct vbus_deviceopen *args) +{ + struct vbus_client *c = cd->client; + + return c->ops->deviceopen(c, cd->ctx, args->devid, args->version, + &args->handle); +} + +static long +_deviceclose(struct userspace_chardev *cd, unsigned long devh) +{ + struct vbus_client *c = cd->client; + + return c->ops->deviceclose(c, devh); +} + +static long +_devicecall(struct userspace_chardev *cd, struct vbus_devicecall *args) +{ + struct vbus_client *c = cd->client; + + return c->ops->devicecall(c, args->devh, args->func, + (void *)args->datap, + args->len, args->flags); +} + +static void* +userspace_vmap(__u64 addr, size_t len) +{ + struct page **page_list; + void *ptr = NULL; + unsigned long base; + off_t offset; + size_t npages; + int ret; + + base = (unsigned long)addr & PAGE_MASK; + offset = (unsigned long)addr & ~PAGE_MASK; + npages = PAGE_ALIGN(len + offset) >> PAGE_SHIFT; + + if (npages > (PAGE_SIZE / sizeof(struct page *))) + return NULL; + + page_list = (struct page **) __get_free_page(GFP_KERNEL); + if (!page_list) + return NULL; + + down_write(¤t->mm->mmap_sem); + + ret = get_user_pages(current, current->mm, base, npages, + 1, 0, page_list, NULL); + if (ret < 0) + goto out; + + ptr = vmap(page_list, npages, VM_MAP, PAGE_KERNEL); + if (ptr) + current->mm->locked_vm += npages; + +out: + up_write(¤t->mm->mmap_sem); + free_page((unsigned long)page_list); + + return ptr+offset; +} + +static struct userspace_signal *to_userspace(struct shm_signal *signal) +{ + return container_of(signal, struct userspace_signal, signal); +} + +static int +userspace_signal_inject(struct shm_signal *signal) +{ + struct userspace_signal *_signal = to_userspace(signal); + struct userspace_chardev *cd = _signal->cd; + unsigned long flags; + + spin_lock_irqsave(&cd->lock, flags); + + if (!_signal->signaled) { + _signal->signaled = 1; + list_add_tail(&_signal->list, &cd->signal_list); + wake_up_interruptible(&cd->wq); + } + + spin_unlock_irqrestore(&cd->lock, flags); + + return 0; +} + +static void +userspace_signal_release(struct shm_signal *signal) +{ + struct userspace_signal *_signal = to_userspace(signal); + + vbus_shm_put(_signal->shm); + kfree(_signal); +} + +static struct shm_signal_ops userspace_signal_ops = { + .inject = userspace_signal_inject, + .release = userspace_signal_release, +}; + +static long +userspace_signal_alloc(struct vbus_shm *shm, + u32 offset, u32 prio, u64 cookie, + struct userspace_signal **usignal) +{ + struct userspace_signal *_signal; + struct shm_signal *signal; + struct shm_signal_desc *desc; + int ret = -EINVAL; + + _signal = kzalloc(sizeof(*_signal), GFP_KERNEL); + if (!_signal) + return -ENOMEM; + + desc = (struct shm_signal_desc *)(shm->ptr + offset); + + if (desc->magic != SHM_SIGNAL_MAGIC) + goto out; + + if (desc->ver != SHM_SIGNAL_VER) + goto out; + + signal = &_signal->signal; + + shm_signal_init(signal); + + signal->locale = shm_locality_south; + signal->ops = &userspace_signal_ops; + signal->desc = desc; + + _signal->shm = shm; + _signal->prio = prio; + _signal->cookie = cookie; + vbus_shm_get(shm); /* dropped when the signal is released */ + + *usignal = _signal; + + return 0; + +out: + kfree(_signal); + + return ret; +} + +static void +userspace_shm_release(struct vbus_shm *shm) +{ + struct userspace_shm *_shm = container_of(shm, struct userspace_shm, + shm); + + /* FIXME: do we need to adjust current->mm->locked_vm? */ + vunmap((void *)((unsigned long)shm->ptr & PAGE_MASK)); + kfree(_shm); +} + +static struct vbus_shm_ops userspace_shm_ops = { + .release = userspace_shm_release, +}; + +static int +userspace_shm_map(struct userspace_chardev *cd, + __u64 ptr, __u32 len, + struct userspace_shm **ushm) +{ + struct userspace_shm *_shm; + struct vbus_shm *shm; + void *vmap; + + _shm = kzalloc(sizeof(*_shm), GFP_KERNEL); + if (!_shm) + return -ENOMEM; + + shm = &_shm->shm; + + vmap = userspace_vmap(ptr, len); + if (!vmap) { + kfree(_shm); + return -EFAULT; + } + + vbus_shm_init(shm, &userspace_shm_ops, vmap, len); + + *ushm = _shm; + + return 0; +} + +static long +_deviceshm(struct userspace_chardev *cd, struct vbus_deviceshm *args) +{ + struct vbus_client *c = cd->client; + struct userspace_signal *_signal = NULL; + struct shm_signal *signal = NULL; + struct userspace_shm *_shm; + u64 handle; + long ret; + + ret = userspace_shm_map(cd, args->datap, args->len, &_shm); + if (ret < 0) + return ret; + + /* + * Establishing a signal is optional + */ + if (args->signal.offset != -1) { + ret = userspace_signal_alloc(&_shm->shm, + args->signal.offset, + args->signal.prio, + args->signal.cookie, + &_signal); + if (ret < 0) + goto out; + + _signal->cd = cd; + signal = &_signal->signal; + } + + ret = c->ops->deviceshm(c, args->devh, args->id, + &_shm->shm, signal, + args->flags, &handle); + if (ret < 0) + goto out; + + args->handle = handle; + + return 0; + +out: + if (signal) + shm_signal_put(signal); + + vbus_shm_put(&_shm->shm); + return ret; +} + +static long +_shmsignal(struct userspace_chardev *cd, unsigned long handle) +{ + struct vbus_client *c = cd->client; + + return c->ops->shmsignal(c, handle); +} + +static int +vbus_chardev_open(struct inode *inode, struct file *filp) +{ + struct vbus *vbus = task_vbus_get(current); + struct vbus_client *client; + struct vbus_memctx *ctx; + struct userspace_chardev *cd; + + if (!vbus) + return -EPERM; + + client = vbus_client_attach(vbus); + vbus_put(vbus); + if (!client) + return -ENOMEM; + + ctx = task_memctx_alloc(current); + if (!ctx) { + vbus_client_put(client); + return -ENOMEM; + } + + cd = kzalloc(sizeof(*cd), GFP_KERNEL); + if (!cd) { + vbus_memctx_put(ctx); + vbus_client_put(client); + return -ENOMEM; + } + + spin_lock_init(&cd->lock); + cd->opened = 0; + cd->client = client; + cd->ctx = ctx; + + INIT_LIST_HEAD(&cd->signal_list); + init_waitqueue_head(&cd->wq); + + filp->private_data = cd; + + return 0; +} + +static long +vbus_chardev_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg) +{ + struct userspace_chardev *cd = filp->private_data; + + if (!cd->opened && ioctl != VBUS_BUSOPEN) + return -EINVAL; + + switch (ioctl) { + case VBUS_BUSOPEN: + return _busopen(cd, (struct vbus_userspace_busopen *)arg); + case VBUS_DEVICEOPEN: + return _deviceopen(cd, (struct vbus_deviceopen *)arg); + case VBUS_DEVICECLOSE: + return _deviceclose(cd, *(__u64 *)arg); + case VBUS_DEVICECALL: + return _devicecall(cd, (struct vbus_devicecall *)arg); + case VBUS_DEVICESHM: + return _deviceshm(cd, (struct vbus_deviceshm *)arg); + case VBUS_SHMSIGNAL: + return _shmsignal(cd, *(__u64 *)arg); + default: + return -EINVAL; + } +} + +static ssize_t +vbus_chardev_read(struct file *filp, char __user *buf, size_t len, + loff_t *ppos) +{ + DEFINE_WAIT(wait); + struct userspace_chardev *cd = filp->private_data; + ssize_t bytes = 0; + int count, i; + __u64 __user *p = (__u64 __user *)buf; + unsigned long flags; + + count = len/sizeof(__u64); + + if (!count) + return -EINVAL; + + spin_lock_irqsave(&cd->lock, flags); + + for (;;) { + prepare_to_wait(&cd->wq, &wait, TASK_INTERRUPTIBLE); + + if (!list_empty(&cd->signal_list)) + break; + + if (signal_pending(current)) { + finish_wait(&cd->wq, &wait); + spin_unlock_irqrestore(&cd->lock, flags); + return -EINTR; + } + + spin_unlock_irqrestore(&cd->lock, flags); + schedule(); + spin_lock_irqsave(&cd->lock, flags); + } + + finish_wait(&cd->wq, &wait); + + for (i = 0; i < count; i++) { + struct userspace_signal *_signal; + __u64 cookie; + + if (list_empty(&cd->signal_list)) + break; + + _signal = list_first_entry(&cd->signal_list, + struct userspace_signal, list); + + _signal->signaled = 0; + list_del(&_signal->list); + + cookie = _signal->cookie; + + put_user(cookie, p++); + + bytes += sizeof(cookie); + } + + spin_unlock_irqrestore(&cd->lock, flags); + + return bytes; +} + +static int +vbus_chardev_release(struct inode *inode, struct file *filp) +{ + struct userspace_chardev *cd = filp->private_data; + + vbus_memctx_put(cd->ctx); + vbus_client_put(cd->client); + kfree(cd); + + return 0; +} + +static const struct file_operations vbus_chardev_ops = { + .open = vbus_chardev_open, + .read = vbus_chardev_read, + .unlocked_ioctl = vbus_chardev_ioctl, + .compat_ioctl = vbus_chardev_ioctl, + .release = vbus_chardev_release, +}; + +static struct miscdevice vbus_chardev = { + MISC_DYNAMIC_MINOR, + "vbus", + &vbus_chardev_ops, +}; + +static int __init +vbus_userspace_init(void) +{ + return misc_register(&vbus_chardev); +} + +static void __exit +vbus_userspace_cleanup(void) +{ + misc_deregister(&vbus_chardev); +} + +module_init(vbus_userspace_init); +module_exit(vbus_userspace_cleanup); -- 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/