diff options
author | Erik Gilling <konkers@android.com> | 2013-03-01 00:42:58 (GMT) |
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committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-03-04 09:40:08 (GMT) |
commit | 9d1906e61dda982070e3910a04d9cce050f7f1a4 (patch) | |
tree | 2efc0efecd0afe6b35358ec35b9ce2e712259a24 /drivers/staging/android/sw_sync.c | |
parent | 7ad530bf2499c702a6dcbb279cf78b76845ed584 (diff) | |
download | linux-9d1906e61dda982070e3910a04d9cce050f7f1a4.tar.xz |
staging: sw_sync: Add cpu based sync driver
Adds a base sync driver that uses the cpu for serialization.
Cc: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Cc: Erik Gilling <konkers@android.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Rob Clark <robclark@gmail.com>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: dri-devel@lists.freedesktop.org
Cc: Android Kernel Team <kernel-team@android.com>
Signed-off-by: Erik Gilling <konkers@android.com>
[jstultz: Add commit message, whitespace fixes and move to
staging directory]
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/staging/android/sw_sync.c')
-rw-r--r-- | drivers/staging/android/sw_sync.c | 224 |
1 files changed, 224 insertions, 0 deletions
diff --git a/drivers/staging/android/sw_sync.c b/drivers/staging/android/sw_sync.c new file mode 100644 index 0000000..c27004c --- /dev/null +++ b/drivers/staging/android/sw_sync.c @@ -0,0 +1,224 @@ +/* + * drivers/base/sw_sync.c + * + * Copyright (C) 2012 Google, Inc. + * + * This software is licensed under the terms of the GNU General Public + * License version 2, as published by the Free Software Foundation, and + * may be copied, distributed, and modified under those terms. + * + * 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/kernel.h> +#include <linux/file.h> +#include <linux/fs.h> +#include <linux/miscdevice.h> +#include <linux/module.h> +#include <linux/syscalls.h> +#include <linux/uaccess.h> + +#include "sw_sync.h" + +static int sw_sync_cmp(u32 a, u32 b) +{ + if (a == b) + return 0; + + return ((s32)a - (s32)b) < 0 ? -1 : 1; +} + +struct sync_pt *sw_sync_pt_create(struct sw_sync_timeline *obj, u32 value) +{ + struct sw_sync_pt *pt; + + pt = (struct sw_sync_pt *) + sync_pt_create(&obj->obj, sizeof(struct sw_sync_pt)); + + pt->value = value; + + return (struct sync_pt *)pt; +} + +static struct sync_pt *sw_sync_pt_dup(struct sync_pt *sync_pt) +{ + struct sw_sync_pt *pt = (struct sw_sync_pt *) sync_pt; + struct sw_sync_timeline *obj = + (struct sw_sync_timeline *)sync_pt->parent; + + return (struct sync_pt *) sw_sync_pt_create(obj, pt->value); +} + +static int sw_sync_pt_has_signaled(struct sync_pt *sync_pt) +{ + struct sw_sync_pt *pt = (struct sw_sync_pt *)sync_pt; + struct sw_sync_timeline *obj = + (struct sw_sync_timeline *)sync_pt->parent; + + return sw_sync_cmp(obj->value, pt->value) >= 0; +} + +static int sw_sync_pt_compare(struct sync_pt *a, struct sync_pt *b) +{ + struct sw_sync_pt *pt_a = (struct sw_sync_pt *)a; + struct sw_sync_pt *pt_b = (struct sw_sync_pt *)b; + + return sw_sync_cmp(pt_a->value, pt_b->value); +} + +struct sync_timeline_ops sw_sync_timeline_ops = { + .driver_name = "sw_sync", + .dup = sw_sync_pt_dup, + .has_signaled = sw_sync_pt_has_signaled, + .compare = sw_sync_pt_compare, +}; + + +struct sw_sync_timeline *sw_sync_timeline_create(const char *name) +{ + struct sw_sync_timeline *obj = (struct sw_sync_timeline *) + sync_timeline_create(&sw_sync_timeline_ops, + sizeof(struct sw_sync_timeline), + name); + + return obj; +} + +void sw_sync_timeline_inc(struct sw_sync_timeline *obj, u32 inc) +{ + obj->value += inc; + + sync_timeline_signal(&obj->obj); +} + + +#ifdef CONFIG_SW_SYNC_USER +/* *WARNING* + * + * improper use of this can result in deadlocking kernel drivers from userspace. + */ + +/* opening sw_sync create a new sync obj */ +int sw_sync_open(struct inode *inode, struct file *file) +{ + struct sw_sync_timeline *obj; + char task_comm[TASK_COMM_LEN]; + + get_task_comm(task_comm, current); + + obj = sw_sync_timeline_create(task_comm); + if (obj == NULL) + return -ENOMEM; + + file->private_data = obj; + + return 0; +} + +int sw_sync_release(struct inode *inode, struct file *file) +{ + struct sw_sync_timeline *obj = file->private_data; + sync_timeline_destroy(&obj->obj); + return 0; +} + +long sw_sync_ioctl_create_fence(struct sw_sync_timeline *obj, unsigned long arg) +{ + int fd = get_unused_fd(); + int err; + struct sync_pt *pt; + struct sync_fence *fence; + struct sw_sync_create_fence_data data; + + if (copy_from_user(&data, (void __user *)arg, sizeof(data))) + return -EFAULT; + + pt = sw_sync_pt_create(obj, data.value); + if (pt == NULL) { + err = -ENOMEM; + goto err; + } + + data.name[sizeof(data.name) - 1] = '\0'; + fence = sync_fence_create(data.name, pt); + if (fence == NULL) { + sync_pt_free(pt); + err = -ENOMEM; + goto err; + } + + data.fence = fd; + if (copy_to_user((void __user *)arg, &data, sizeof(data))) { + sync_fence_put(fence); + err = -EFAULT; + goto err; + } + + sync_fence_install(fence, fd); + + return 0; + +err: + put_unused_fd(fd); + return err; +} + +long sw_sync_ioctl_inc(struct sw_sync_timeline *obj, unsigned long arg) +{ + u32 value; + + if (copy_from_user(&value, (void __user *)arg, sizeof(value))) + return -EFAULT; + + sw_sync_timeline_inc(obj, value); + + return 0; +} + +long sw_sync_ioctl(struct file *file, unsigned int cmd, unsigned long arg) +{ + struct sw_sync_timeline *obj = file->private_data; + + switch (cmd) { + case SW_SYNC_IOC_CREATE_FENCE: + return sw_sync_ioctl_create_fence(obj, arg); + + case SW_SYNC_IOC_INC: + return sw_sync_ioctl_inc(obj, arg); + + default: + return -ENOTTY; + } +} + +static const struct file_operations sw_sync_fops = { + .owner = THIS_MODULE, + .open = sw_sync_open, + .release = sw_sync_release, + .unlocked_ioctl = sw_sync_ioctl, +}; + +static struct miscdevice sw_sync_dev = { + .minor = MISC_DYNAMIC_MINOR, + .name = "sw_sync", + .fops = &sw_sync_fops, +}; + +int __init sw_sync_device_init(void) +{ + return misc_register(&sw_sync_dev); +} + +void __exit sw_sync_device_remove(void) +{ + misc_deregister(&sw_sync_dev); +} + +module_init(sw_sync_device_init); +module_exit(sw_sync_device_remove); + +#endif /* CONFIG_SW_SYNC_USER */ |