drivers/net/netdevsim/dev.c

Source file repositories/reference/linux-study-clean/drivers/net/netdevsim/dev.c

File Facts

System
Linux kernel
Corpus path
drivers/net/netdevsim/dev.c
Extension
.c
Size
53430 bytes
Lines
1909
Domain
Driver Families
Bucket
drivers/net
Inferred role
Driver Families: operation-table or driver-model contract
Status
pattern implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

static const struct file_operations nsim_dev_take_snapshot_fops = {
	.open = simple_open,
	.write = nsim_dev_take_snapshot_write,
	.llseek = generic_file_llseek,
	.owner = THIS_MODULE,
};

static ssize_t nsim_dev_trap_fa_cookie_read(struct file *file,
					    char __user *data,
					    size_t count, loff_t *ppos)
{
	struct nsim_dev *nsim_dev = file->private_data;
	struct flow_action_cookie *fa_cookie;
	unsigned int buf_len;
	ssize_t ret;
	char *buf;

	spin_lock(&nsim_dev->fa_cookie_lock);
	fa_cookie = nsim_dev->fa_cookie;
	if (!fa_cookie) {
		ret = -EINVAL;
		goto errout;
	}
	buf_len = fa_cookie->cookie_len * 2;
	buf = kmalloc(buf_len, GFP_ATOMIC);
	if (!buf) {
		ret = -ENOMEM;
		goto errout;
	}
	bin2hex(buf, fa_cookie->cookie, fa_cookie->cookie_len);
	spin_unlock(&nsim_dev->fa_cookie_lock);

	ret = simple_read_from_buffer(data, count, ppos, buf, buf_len);

	kfree(buf);
	return ret;

errout:
	spin_unlock(&nsim_dev->fa_cookie_lock);
	return ret;
}

static ssize_t nsim_dev_trap_fa_cookie_write(struct file *file,
					     const char __user *data,
					     size_t count, loff_t *ppos)
{
	struct nsim_dev *nsim_dev = file->private_data;
	struct flow_action_cookie *fa_cookie;
	size_t cookie_len;
	ssize_t ret;
	char *buf;

	if (*ppos != 0)
		return -EINVAL;
	cookie_len = (count - 1) / 2;
	if ((count - 1) % 2)
		return -EINVAL;

	buf = memdup_user(data, count);
	if (IS_ERR(buf))
		return PTR_ERR(buf);

	fa_cookie = kmalloc(sizeof(*fa_cookie) + cookie_len,
			    GFP_KERNEL | __GFP_NOWARN);
	if (!fa_cookie) {
		ret = -ENOMEM;
		goto free_buf;
	}

	fa_cookie->cookie_len = cookie_len;
	ret = hex2bin(fa_cookie->cookie, buf, cookie_len);
	if (ret)
		goto free_fa_cookie;
	kfree(buf);

	spin_lock(&nsim_dev->fa_cookie_lock);
	kfree(nsim_dev->fa_cookie);
	nsim_dev->fa_cookie = fa_cookie;
	spin_unlock(&nsim_dev->fa_cookie_lock);

	return count;

free_fa_cookie:
	kfree(fa_cookie);
free_buf:
	kfree(buf);
	return ret;
}

static const struct file_operations nsim_dev_trap_fa_cookie_fops = {

Annotation

Implementation Notes