coh901318: don't open-code simple_read_from_buffer()

... and BTW, failing copy_to_user() means EFAULT, not EINVAL

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro 2013-07-16 17:58:45 +04:00
parent badcf2b7b8
commit 5d30b4274f

View File

@ -1339,15 +1339,14 @@ static int coh901318_debugfs_read(struct file *file, char __user *buf,
{
u64 started_channels = debugfs_dma_base->pm.started_channels;
int pool_count = debugfs_dma_base->pool.debugfs_pool_counter;
int i;
int ret = 0;
char *dev_buf;
char *tmp;
int dev_size;
int ret;
int i;
dev_buf = kmalloc(4*1024, GFP_KERNEL);
if (dev_buf == NULL)
goto err_kmalloc;
return -ENOMEM;
tmp = dev_buf;
tmp += sprintf(tmp, "DMA -- enabled dma channels\n");
@ -1357,26 +1356,11 @@ static int coh901318_debugfs_read(struct file *file, char __user *buf,
tmp += sprintf(tmp, "channel %d\n", i);
tmp += sprintf(tmp, "Pool alloc nbr %d\n", pool_count);
dev_size = tmp - dev_buf;
/* No more to read if offset != 0 */
if (*f_pos > dev_size)
goto out;
if (count > dev_size - *f_pos)
count = dev_size - *f_pos;
if (copy_to_user(buf, dev_buf + *f_pos, count))
ret = -EINVAL;
ret = count;
*f_pos += count;
out:
ret = simple_read_from_buffer(buf, count, f_pos, dev_buf,
tmp - dev_buf);
kfree(dev_buf);
return ret;
err_kmalloc:
return 0;
}
static const struct file_operations coh901318_debugfs_status_operations = {