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-rw-r--r--drivers/dma-buf/Kconfig11
-rw-r--r--drivers/dma-buf/Makefile1
-rw-r--r--drivers/dma-buf/sync_file.c395
3 files changed, 407 insertions, 0 deletions
diff --git a/drivers/dma-buf/Kconfig b/drivers/dma-buf/Kconfig
new file mode 100644
index 000000000000..9824bc4addf8
--- /dev/null
+++ b/drivers/dma-buf/Kconfig
@@ -0,0 +1,11 @@
+menu "DMABUF options"
+
+config SYNC_FILE
+ bool "sync_file support for fences"
+ default n
+ select ANON_INODES
+ select DMA_SHARED_BUFFER
+ ---help---
+ This option enables the fence framework synchronization to export
+ sync_files to userspace that can represent one or more fences.
+endmenu
diff --git a/drivers/dma-buf/Makefile b/drivers/dma-buf/Makefile
index 57a675f90cd0..4a424eca75ed 100644
--- a/drivers/dma-buf/Makefile
+++ b/drivers/dma-buf/Makefile
@@ -1 +1,2 @@
obj-y := dma-buf.o fence.o reservation.o seqno-fence.o
+obj-$(CONFIG_SYNC_FILE) += sync_file.o
diff --git a/drivers/dma-buf/sync_file.c b/drivers/dma-buf/sync_file.c
new file mode 100644
index 000000000000..f08cf2d8309e
--- /dev/null
+++ b/drivers/dma-buf/sync_file.c
@@ -0,0 +1,395 @@
+/*
+ * drivers/dma-buf/sync_file.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/export.h>
+#include <linux/file.h>
+#include <linux/fs.h>
+#include <linux/kernel.h>
+#include <linux/poll.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+#include <linux/anon_inodes.h>
+#include <linux/sync_file.h>
+#include <uapi/linux/sync_file.h>
+
+static const struct file_operations sync_file_fops;
+
+static struct sync_file *sync_file_alloc(int size)
+{
+ struct sync_file *sync_file;
+
+ sync_file = kzalloc(size, GFP_KERNEL);
+ if (!sync_file)
+ return NULL;
+
+ sync_file->file = anon_inode_getfile("sync_file", &sync_file_fops,
+ sync_file, 0);
+ if (IS_ERR(sync_file->file))
+ goto err;
+
+ kref_init(&sync_file->kref);
+
+ init_waitqueue_head(&sync_file->wq);
+
+ return sync_file;
+
+err:
+ kfree(sync_file);
+ return NULL;
+}
+
+static void fence_check_cb_func(struct fence *f, struct fence_cb *cb)
+{
+ struct sync_file_cb *check;
+ struct sync_file *sync_file;
+
+ check = container_of(cb, struct sync_file_cb, cb);
+ sync_file = check->sync_file;
+
+ if (atomic_dec_and_test(&sync_file->status))
+ wake_up_all(&sync_file->wq);
+}
+
+/**
+ * sync_file_create() - creates a sync file
+ * @fence: fence to add to the sync_fence
+ *
+ * Creates a sync_file containg @fence. Once this is called, the sync_file
+ * takes ownership of @fence. The sync_file can be released with
+ * fput(sync_file->file). Returns the sync_file or NULL in case of error.
+ */
+struct sync_file *sync_file_create(struct fence *fence)
+{
+ struct sync_file *sync_file;
+
+ sync_file = sync_file_alloc(offsetof(struct sync_file, cbs[1]));
+ if (!sync_file)
+ return NULL;
+
+ sync_file->num_fences = 1;
+ atomic_set(&sync_file->status, 1);
+ snprintf(sync_file->name, sizeof(sync_file->name), "%s-%s%d-%d",
+ fence->ops->get_driver_name(fence),
+ fence->ops->get_timeline_name(fence), fence->context,
+ fence->seqno);
+
+ sync_file->cbs[0].fence = fence;
+ sync_file->cbs[0].sync_file = sync_file;
+ if (fence_add_callback(fence, &sync_file->cbs[0].cb,
+ fence_check_cb_func))
+ atomic_dec(&sync_file->status);
+
+ return sync_file;
+}
+EXPORT_SYMBOL(sync_file_create);
+
+/**
+ * sync_file_fdget() - get a sync_file from an fd
+ * @fd: fd referencing a fence
+ *
+ * Ensures @fd references a valid sync_file, increments the refcount of the
+ * backing file. Returns the sync_file or NULL in case of error.
+ */
+static struct sync_file *sync_file_fdget(int fd)
+{
+ struct file *file = fget(fd);
+
+ if (!file)
+ return NULL;
+
+ if (file->f_op != &sync_file_fops)
+ goto err;
+
+ return file->private_data;
+
+err:
+ fput(file);
+ return NULL;
+}
+
+static void sync_file_add_pt(struct sync_file *sync_file, int *i,
+ struct fence *fence)
+{
+ sync_file->cbs[*i].fence = fence;
+ sync_file->cbs[*i].sync_file = sync_file;
+
+ if (!fence_add_callback(fence, &sync_file->cbs[*i].cb,
+ fence_check_cb_func)) {
+ fence_get(fence);
+ (*i)++;
+ }
+}
+
+/**
+ * sync_file_merge() - merge two sync_files
+ * @name: name of new fence
+ * @a: sync_file a
+ * @b: sync_file b
+ *
+ * Creates a new sync_file which contains copies of all the fences in both
+ * @a and @b. @a and @b remain valid, independent sync_file. Returns the
+ * new merged sync_file or NULL in case of error.
+ */
+static struct sync_file *sync_file_merge(const char *name, struct sync_file *a,
+ struct sync_file *b)
+{
+ int num_fences = a->num_fences + b->num_fences;
+ struct sync_file *sync_file;
+ int i, i_a, i_b;
+ unsigned long size = offsetof(struct sync_file, cbs[num_fences]);
+
+ sync_file = sync_file_alloc(size);
+ if (!sync_file)
+ return NULL;
+
+ atomic_set(&sync_file->status, num_fences);
+
+ /*
+ * Assume sync_file a and b are both ordered and have no
+ * duplicates with the same context.
+ *
+ * If a sync_file can only be created with sync_file_merge
+ * and sync_file_create, this is a reasonable assumption.
+ */
+ for (i = i_a = i_b = 0; i_a < a->num_fences && i_b < b->num_fences; ) {
+ struct fence *pt_a = a->cbs[i_a].fence;
+ struct fence *pt_b = b->cbs[i_b].fence;
+
+ if (pt_a->context < pt_b->context) {
+ sync_file_add_pt(sync_file, &i, pt_a);
+
+ i_a++;
+ } else if (pt_a->context > pt_b->context) {
+ sync_file_add_pt(sync_file, &i, pt_b);
+
+ i_b++;
+ } else {
+ if (pt_a->seqno - pt_b->seqno <= INT_MAX)
+ sync_file_add_pt(sync_file, &i, pt_a);
+ else
+ sync_file_add_pt(sync_file, &i, pt_b);
+
+ i_a++;
+ i_b++;
+ }
+ }
+
+ for (; i_a < a->num_fences; i_a++)
+ sync_file_add_pt(sync_file, &i, a->cbs[i_a].fence);
+
+ for (; i_b < b->num_fences; i_b++)
+ sync_file_add_pt(sync_file, &i, b->cbs[i_b].fence);
+
+ if (num_fences > i)
+ atomic_sub(num_fences - i, &sync_file->status);
+ sync_file->num_fences = i;
+
+ strlcpy(sync_file->name, name, sizeof(sync_file->name));
+ return sync_file;
+}
+
+static void sync_file_free(struct kref *kref)
+{
+ struct sync_file *sync_file = container_of(kref, struct sync_file,
+ kref);
+ int i;
+
+ for (i = 0; i < sync_file->num_fences; ++i) {
+ fence_remove_callback(sync_file->cbs[i].fence,
+ &sync_file->cbs[i].cb);
+ fence_put(sync_file->cbs[i].fence);
+ }
+
+ kfree(sync_file);
+}
+
+static int sync_file_release(struct inode *inode, struct file *file)
+{
+ struct sync_file *sync_file = file->private_data;
+
+ kref_put(&sync_file->kref, sync_file_free);
+ return 0;
+}
+
+static unsigned int sync_file_poll(struct file *file, poll_table *wait)
+{
+ struct sync_file *sync_file = file->private_data;
+ int status;
+
+ poll_wait(file, &sync_file->wq, wait);
+
+ status = atomic_read(&sync_file->status);
+
+ if (!status)
+ return POLLIN;
+ if (status < 0)
+ return POLLERR;
+ return 0;
+}
+
+static long sync_file_ioctl_merge(struct sync_file *sync_file,
+ unsigned long arg)
+{
+ int fd = get_unused_fd_flags(O_CLOEXEC);
+ int err;
+ struct sync_file *fence2, *fence3;
+ struct sync_merge_data data;
+
+ if (fd < 0)
+ return fd;
+
+ if (copy_from_user(&data, (void __user *)arg, sizeof(data))) {
+ err = -EFAULT;
+ goto err_put_fd;
+ }
+
+ if (data.flags || data.pad) {
+ err = -EINVAL;
+ goto err_put_fd;
+ }
+
+ fence2 = sync_file_fdget(data.fd2);
+ if (!fence2) {
+ err = -ENOENT;
+ goto err_put_fd;
+ }
+
+ data.name[sizeof(data.name) - 1] = '\0';
+ fence3 = sync_file_merge(data.name, sync_file, fence2);
+ if (!fence3) {
+ err = -ENOMEM;
+ goto err_put_fence2;
+ }
+
+ data.fence = fd;
+ if (copy_to_user((void __user *)arg, &data, sizeof(data))) {
+ err = -EFAULT;
+ goto err_put_fence3;
+ }
+
+ fd_install(fd, fence3->file);
+ fput(fence2->file);
+ return 0;
+
+err_put_fence3:
+ fput(fence3->file);
+
+err_put_fence2:
+ fput(fence2->file);
+
+err_put_fd:
+ put_unused_fd(fd);
+ return err;
+}
+
+static void sync_fill_fence_info(struct fence *fence,
+ struct sync_fence_info *info)
+{
+ strlcpy(info->obj_name, fence->ops->get_timeline_name(fence),
+ sizeof(info->obj_name));
+ strlcpy(info->driver_name, fence->ops->get_driver_name(fence),
+ sizeof(info->driver_name));
+ if (fence_is_signaled(fence))
+ info->status = fence->status >= 0 ? 1 : fence->status;
+ else
+ info->status = 0;
+ info->timestamp_ns = ktime_to_ns(fence->timestamp);
+}
+
+static long sync_file_ioctl_fence_info(struct sync_file *sync_file,
+ unsigned long arg)
+{
+ struct sync_file_info info;
+ struct sync_fence_info *fence_info = NULL;
+ __u32 size;
+ int ret, i;
+
+ if (copy_from_user(&info, (void __user *)arg, sizeof(info)))
+ return -EFAULT;
+
+ if (info.flags || info.pad)
+ return -EINVAL;
+
+ /*
+ * Passing num_fences = 0 means that userspace doesn't want to
+ * retrieve any sync_fence_info. If num_fences = 0 we skip filling
+ * sync_fence_info and return the actual number of fences on
+ * info->num_fences.
+ */
+ if (!info.num_fences)
+ goto no_fences;
+
+ if (info.num_fences < sync_file->num_fences)
+ return -EINVAL;
+
+ size = sync_file->num_fences * sizeof(*fence_info);
+ fence_info = kzalloc(size, GFP_KERNEL);
+ if (!fence_info)
+ return -ENOMEM;
+
+ for (i = 0; i < sync_file->num_fences; ++i)
+ sync_fill_fence_info(sync_file->cbs[i].fence, &fence_info[i]);
+
+ if (copy_to_user(u64_to_user_ptr(info.sync_fence_info), fence_info,
+ size)) {
+ ret = -EFAULT;
+ goto out;
+ }
+
+no_fences:
+ strlcpy(info.name, sync_file->name, sizeof(info.name));
+ info.status = atomic_read(&sync_file->status);
+ if (info.status >= 0)
+ info.status = !info.status;
+
+ info.num_fences = sync_file->num_fences;
+
+ if (copy_to_user((void __user *)arg, &info, sizeof(info)))
+ ret = -EFAULT;
+ else
+ ret = 0;
+
+out:
+ kfree(fence_info);
+
+ return ret;
+}
+
+static long sync_file_ioctl(struct file *file, unsigned int cmd,
+ unsigned long arg)
+{
+ struct sync_file *sync_file = file->private_data;
+
+ switch (cmd) {
+ case SYNC_IOC_MERGE:
+ return sync_file_ioctl_merge(sync_file, arg);
+
+ case SYNC_IOC_FILE_INFO:
+ return sync_file_ioctl_fence_info(sync_file, arg);
+
+ default:
+ return -ENOTTY;
+ }
+}
+
+static const struct file_operations sync_file_fops = {
+ .release = sync_file_release,
+ .poll = sync_file_poll,
+ .unlocked_ioctl = sync_file_ioctl,
+ .compat_ioctl = sync_file_ioctl,
+};
+
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-22 20:18:41 +0000