Commit a3353ec3 authored by Jakub Kicinski's avatar Jakub Kicinski Committed by David S. Miller
Browse files

netdevsim: move max vf config to dev 



max_vfs is a strange little beast because the file
hangs off of nsim's debugfs, but it configures a field
in the bus device. Move it to dev.c, let's look at it
as if the device driver was imposing VF limit based
on FW info (like pci_sriov_set_totalvfs()).

Again, when moving refactor the function not to hold
the vfs lock pointlessly while parsing the input.
Wrap the access from the read side in READ_ONCE()
to appease concurrency checkers. Do not check if
return value from snprintf() is negative...

Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 1c401078

drivers/net/netdevsim/bus.c

+0 −75
Original line number Diff line number Diff line
@@ -57,81 +57,6 @@ static struct device_attribute nsim_bus_dev_numvfs_attr = 
	__ATTR(sriov_numvfs, 0664, nsim_bus_dev_numvfs_show,

	       nsim_bus_dev_numvfs_store);



ssize_t nsim_bus_dev_max_vfs_read(struct file *file,

				  char __user *data,

				  size_t count, loff_t *ppos)

{

	struct nsim_dev *nsim_dev = file->private_data;

	struct nsim_bus_dev *nsim_bus_dev = nsim_dev->nsim_bus_dev;

	char buf[11];

	ssize_t len;



	len = snprintf(buf, sizeof(buf), "%u\n", nsim_bus_dev->max_vfs);

	if (len < 0)

		return len;



	return simple_read_from_buffer(data, count, ppos, buf, len);

}



ssize_t nsim_bus_dev_max_vfs_write(struct file *file,

				   const char __user *data,

				   size_t count, loff_t *ppos)

{

	struct nsim_dev *nsim_dev = file->private_data;

	struct nsim_bus_dev *nsim_bus_dev = nsim_dev->nsim_bus_dev;

	struct nsim_vf_config *vfconfigs;

	ssize_t ret;

	char buf[10];

	u32 val;



	if (*ppos != 0)

		return 0;



	if (count >= sizeof(buf))

		return -ENOSPC;



	mutex_lock(&nsim_dev->vfs_lock);

	/* Reject if VFs are configured */

	if (nsim_bus_dev->num_vfs) {

		ret = -EBUSY;

		goto unlock;

	}



	ret = copy_from_user(buf, data, count);

	if (ret) {

		ret = -EFAULT;

		goto unlock;

	}



	buf[count] = '\0';

	ret = kstrtouint(buf, 10, &val);

	if (ret) {

		ret = -EIO;

		goto unlock;

	}



	/* max_vfs limited by the maximum number of provided port indexes */

	if (val > NSIM_DEV_VF_PORT_INDEX_MAX - NSIM_DEV_VF_PORT_INDEX_BASE) {

		ret = -ERANGE;

		goto unlock;

	}



	vfconfigs = kcalloc(val, sizeof(struct nsim_vf_config), GFP_KERNEL | __GFP_NOWARN);

	if (!vfconfigs) {

		ret = -ENOMEM;

		goto unlock;

	}



	kfree(nsim_dev->vfconfigs);

	nsim_dev->vfconfigs = vfconfigs;

	nsim_bus_dev->max_vfs = val;

	*ppos += count;

	ret = count;

unlock:

	mutex_unlock(&nsim_dev->vfs_lock);

	return ret;

}



static ssize_t

new_port_store(struct device *dev, struct device_attribute *attr,

	       const char *buf, size_t count)

drivers/net/netdevsim/dev.c

+64 −0
Original line number Diff line number Diff line
@@ -227,6 +227,70 @@ static const struct file_operations nsim_dev_trap_fa_cookie_fops = { 
	.owner = THIS_MODULE,

};



static ssize_t nsim_bus_dev_max_vfs_read(struct file *file, char __user *data,

					 size_t count, loff_t *ppos)

{

	struct nsim_dev *nsim_dev = file->private_data;

	char buf[11];

	ssize_t len;



	len = scnprintf(buf, sizeof(buf), "%u\n",

			READ_ONCE(nsim_dev->nsim_bus_dev->max_vfs));



	return simple_read_from_buffer(data, count, ppos, buf, len);

}



static ssize_t nsim_bus_dev_max_vfs_write(struct file *file,

					  const char __user *data,

					  size_t count, loff_t *ppos)

{

	struct nsim_vf_config *vfconfigs;

	struct nsim_dev *nsim_dev;

	char buf[10];

	ssize_t ret;

	u32 val;



	if (*ppos != 0)

		return 0;



	if (count >= sizeof(buf))

		return -ENOSPC;



	ret = copy_from_user(buf, data, count);

	if (ret)

		return -EFAULT;

	buf[count] = '\0';



	ret = kstrtouint(buf, 10, &val);

	if (ret)

		return -EINVAL;



	/* max_vfs limited by the maximum number of provided port indexes */

	if (val > NSIM_DEV_VF_PORT_INDEX_MAX - NSIM_DEV_VF_PORT_INDEX_BASE)

		return -ERANGE;



	vfconfigs = kcalloc(val, sizeof(struct nsim_vf_config),

			    GFP_KERNEL | __GFP_NOWARN);

	if (!vfconfigs)

		return -ENOMEM;



	nsim_dev = file->private_data;

	mutex_lock(&nsim_dev->vfs_lock);

	/* Reject if VFs are configured */

	if (nsim_dev_get_vfs(nsim_dev)) {

		ret = -EBUSY;

	} else {

		swap(nsim_dev->vfconfigs, vfconfigs);

		WRITE_ONCE(nsim_dev->nsim_bus_dev->max_vfs, val);

		*ppos += count;

		ret = count;

	}

	mutex_unlock(&nsim_dev->vfs_lock);



	kfree(vfconfigs);

	return ret;

}



static const struct file_operations nsim_dev_max_vfs_fops = {

	.open = simple_open,

	.read = nsim_bus_dev_max_vfs_read,

drivers/net/netdevsim/netdevsim.h

+0 −7
Original line number Diff line number Diff line
@@ -317,13 +317,6 @@ void nsim_fib_destroy(struct devlink *devlink, struct nsim_fib_data *fib_data); 
u64 nsim_fib_get_val(struct nsim_fib_data *fib_data,

		     enum nsim_resource_id res_id, bool max);



ssize_t nsim_bus_dev_max_vfs_read(struct file *file,

				  char __user *data,

				  size_t count, loff_t *ppos);

ssize_t nsim_bus_dev_max_vfs_write(struct file *file,

				   const char __user *data,

				   size_t count, loff_t *ppos);



static inline bool nsim_dev_port_is_pf(struct nsim_dev_port *nsim_dev_port)

{

	return nsim_dev_port->port_type == NSIM_DEV_PORT_TYPE_PF;