+++ /dev/null
-/*
- * drivers/dma-buf/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/file.h>
-#include <linux/fs.h>
-#include <linux/uaccess.h>
-#include <linux/slab.h>
-#include <linux/sync_file.h>
-
-#include "sync_debug.h"
-
-#define CREATE_TRACE_POINTS
-#include "trace/sync.h"
-
-struct sw_sync_create_fence_data {
- __u32 value;
- char name[32];
- __s32 fence; /* fd of new fence */
-};
-
-#define SW_SYNC_IOC_MAGIC 'W'
-
-#define SW_SYNC_IOC_CREATE_FENCE _IOWR(SW_SYNC_IOC_MAGIC, 0,\
- struct sw_sync_create_fence_data)
-#define SW_SYNC_IOC_INC _IOW(SW_SYNC_IOC_MAGIC, 1, __u32)
-
-static const struct fence_ops timeline_fence_ops;
-
-static inline struct sync_pt *fence_to_sync_pt(struct fence *fence)
-{
- if (fence->ops != &timeline_fence_ops)
- return NULL;
- return container_of(fence, struct sync_pt, base);
-}
-
-/**
- * sync_timeline_create() - creates a sync object
- * @name: sync_timeline name
- *
- * Creates a new sync_timeline. Returns the sync_timeline object or NULL in
- * case of error.
- */
-struct sync_timeline *sync_timeline_create(const char *name)
-{
- struct sync_timeline *obj;
-
- obj = kzalloc(sizeof(*obj), GFP_KERNEL);
- if (!obj)
- return NULL;
-
- kref_init(&obj->kref);
- obj->context = fence_context_alloc(1);
- strlcpy(obj->name, name, sizeof(obj->name));
-
- INIT_LIST_HEAD(&obj->child_list_head);
- INIT_LIST_HEAD(&obj->active_list_head);
- spin_lock_init(&obj->child_list_lock);
-
- sync_timeline_debug_add(obj);
-
- return obj;
-}
-
-static void sync_timeline_free(struct kref *kref)
-{
- struct sync_timeline *obj =
- container_of(kref, struct sync_timeline, kref);
-
- sync_timeline_debug_remove(obj);
-
- kfree(obj);
-}
-
-static void sync_timeline_get(struct sync_timeline *obj)
-{
- kref_get(&obj->kref);
-}
-
-static void sync_timeline_put(struct sync_timeline *obj)
-{
- kref_put(&obj->kref, sync_timeline_free);
-}
-
-/**
- * sync_timeline_signal() - signal a status change on a sync_timeline
- * @obj: sync_timeline to signal
- * @inc: num to increment on timeline->value
- *
- * A sync implementation should call this any time one of it's fences
- * has signaled or has an error condition.
- */
-static void sync_timeline_signal(struct sync_timeline *obj, unsigned int inc)
-{
- unsigned long flags;
- struct sync_pt *pt, *next;
-
- trace_sync_timeline(obj);
-
- spin_lock_irqsave(&obj->child_list_lock, flags);
-
- obj->value += inc;
-
- list_for_each_entry_safe(pt, next, &obj->active_list_head,
- active_list) {
- if (fence_is_signaled_locked(&pt->base))
- list_del_init(&pt->active_list);
- }
-
- spin_unlock_irqrestore(&obj->child_list_lock, flags);
-}
-
-/**
- * sync_pt_create() - creates a sync pt
- * @parent: fence's parent sync_timeline
- * @size: size to allocate for this pt
- * @inc: value of the fence
- *
- * Creates a new sync_pt as a child of @parent. @size bytes will be
- * allocated allowing for implementation specific data to be kept after
- * the generic sync_timeline struct. Returns the sync_pt object or
- * NULL in case of error.
- */
-static struct sync_pt *sync_pt_create(struct sync_timeline *obj, int size,
- unsigned int value)
-{
- unsigned long flags;
- struct sync_pt *pt;
-
- if (size < sizeof(*pt))
- return NULL;
-
- pt = kzalloc(size, GFP_KERNEL);
- if (!pt)
- return NULL;
-
- spin_lock_irqsave(&obj->child_list_lock, flags);
- sync_timeline_get(obj);
- fence_init(&pt->base, &timeline_fence_ops, &obj->child_list_lock,
- obj->context, value);
- list_add_tail(&pt->child_list, &obj->child_list_head);
- INIT_LIST_HEAD(&pt->active_list);
- spin_unlock_irqrestore(&obj->child_list_lock, flags);
- return pt;
-}
-
-static const char *timeline_fence_get_driver_name(struct fence *fence)
-{
- return "sw_sync";
-}
-
-static const char *timeline_fence_get_timeline_name(struct fence *fence)
-{
- struct sync_timeline *parent = fence_parent(fence);
-
- return parent->name;
-}
-
-static void timeline_fence_release(struct fence *fence)
-{
- struct sync_pt *pt = fence_to_sync_pt(fence);
- struct sync_timeline *parent = fence_parent(fence);
- unsigned long flags;
-
- spin_lock_irqsave(fence->lock, flags);
- list_del(&pt->child_list);
- if (WARN_ON_ONCE(!list_empty(&pt->active_list)))
- list_del(&pt->active_list);
- spin_unlock_irqrestore(fence->lock, flags);
-
- sync_timeline_put(parent);
- fence_free(fence);
-}
-
-static bool timeline_fence_signaled(struct fence *fence)
-{
- struct sync_timeline *parent = fence_parent(fence);
-
- return (fence->seqno > parent->value) ? false : true;
-}
-
-static bool timeline_fence_enable_signaling(struct fence *fence)
-{
- struct sync_pt *pt = fence_to_sync_pt(fence);
- struct sync_timeline *parent = fence_parent(fence);
-
- if (timeline_fence_signaled(fence))
- return false;
-
- list_add_tail(&pt->active_list, &parent->active_list_head);
- return true;
-}
-
-static void timeline_fence_value_str(struct fence *fence,
- char *str, int size)
-{
- snprintf(str, size, "%d", fence->seqno);
-}
-
-static void timeline_fence_timeline_value_str(struct fence *fence,
- char *str, int size)
-{
- struct sync_timeline *parent = fence_parent(fence);
-
- snprintf(str, size, "%d", parent->value);
-}
-
-static const struct fence_ops timeline_fence_ops = {
- .get_driver_name = timeline_fence_get_driver_name,
- .get_timeline_name = timeline_fence_get_timeline_name,
- .enable_signaling = timeline_fence_enable_signaling,
- .signaled = timeline_fence_signaled,
- .wait = fence_default_wait,
- .release = timeline_fence_release,
- .fence_value_str = timeline_fence_value_str,
- .timeline_value_str = timeline_fence_timeline_value_str,
-};
-
-/*
- * *WARNING*
- *
- * improper use of this can result in deadlocking kernel drivers from userspace.
- */
-
-/* opening sw_sync create a new sync obj */
-static int sw_sync_debugfs_open(struct inode *inode, struct file *file)
-{
- struct sync_timeline *obj;
- char task_comm[TASK_COMM_LEN];
-
- get_task_comm(task_comm, current);
-
- obj = sync_timeline_create(task_comm);
- if (!obj)
- return -ENOMEM;
-
- file->private_data = obj;
-
- return 0;
-}
-
-static int sw_sync_debugfs_release(struct inode *inode, struct file *file)
-{
- struct sync_timeline *obj = file->private_data;
-
- smp_wmb();
-
- sync_timeline_put(obj);
- return 0;
-}
-
-static long sw_sync_ioctl_create_fence(struct sync_timeline *obj,
- unsigned long arg)
-{
- int fd = get_unused_fd_flags(O_CLOEXEC);
- int err;
- struct sync_pt *pt;
- struct sync_file *sync_file;
- struct sw_sync_create_fence_data data;
-
- if (fd < 0)
- return fd;
-
- if (copy_from_user(&data, (void __user *)arg, sizeof(data))) {
- err = -EFAULT;
- goto err;
- }
-
- pt = sync_pt_create(obj, sizeof(*pt), data.value);
- if (!pt) {
- err = -ENOMEM;
- goto err;
- }
-
- sync_file = sync_file_create(&pt->base);
- if (!sync_file) {
- fence_put(&pt->base);
- err = -ENOMEM;
- goto err;
- }
-
- data.fence = fd;
- if (copy_to_user((void __user *)arg, &data, sizeof(data))) {
- fput(sync_file->file);
- err = -EFAULT;
- goto err;
- }
-
- fd_install(fd, sync_file->file);
-
- return 0;
-
-err:
- put_unused_fd(fd);
- return err;
-}
-
-static long sw_sync_ioctl_inc(struct sync_timeline *obj, unsigned long arg)
-{
- u32 value;
-
- if (copy_from_user(&value, (void __user *)arg, sizeof(value)))
- return -EFAULT;
-
- sync_timeline_signal(obj, value);
-
- return 0;
-}
-
-static long sw_sync_ioctl(struct file *file, unsigned int cmd,
- unsigned long arg)
-{
- struct 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;
- }
-}
-
-const struct file_operations sw_sync_debugfs_fops = {
- .open = sw_sync_debugfs_open,
- .release = sw_sync_debugfs_release,
- .unlocked_ioctl = sw_sync_ioctl,
- .compat_ioctl = sw_sync_ioctl,
-};
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