#ifndef __MAC802154_DRIVER_OPS
#define __MAC802154_DRIVER_OPS

#include <linux/types.h>
#include <linux/rtnetlink.h>

#include <net/mac802154.h>

#include "ieee802154_i.h"
#include "trace.h"

static inline int
drv_xmit_async(struct ieee802154_local *local, struct sk_buff *skb)
{
	return local->ops->xmit_async(&local->hw, skb);
}

static inline int
drv_xmit_sync(struct ieee802154_local *local, struct sk_buff *skb)
{
	might_sleep();

	return local->ops->xmit_sync(&local->hw, skb);
}

static inline int drv_start(struct ieee802154_local *local)
{
	int ret;

	might_sleep();

	trace_802154_drv_start(local);
	local->started = true;
	smp_mb();
	ret = local->ops->start(&local->hw);
	trace_802154_drv_return_int(local, ret);
	return ret;
}

static inline void drv_stop(struct ieee802154_local *local)
{
	might_sleep();

	trace_802154_drv_stop(local);
	local->ops->stop(&local->hw);
	trace_802154_drv_return_void(local);

	/* sync away all work on the tasklet before clearing started */
	tasklet_disable(&local->tasklet);
	tasklet_enable(&local->tasklet);

	barrier();

	local->started = false;
}

static inline int
drv_set_channel(struct ieee802154_local *local, u8 page, u8 channel)
{
	int ret;

	might_sleep();

	trace_802154_drv_set_channel(local, page, channel);
	ret = local->ops->set_channel(&local->hw, page, channel);
	trace_802154_drv_return_int(local, ret);
	return ret;
}

static inline int drv_set_tx_power(struct ieee802154_local *local, s32 mbm)
{
	int ret;

	might_sleep();

	if (!local->ops->set_txpower) {
		WARN_ON(1);
		return -EOPNOTSUPP;
	}

	trace_802154_drv_set_tx_power(local, mbm);
	ret = local->ops->set_txpower(&local->hw, mbm);
	trace_802154_drv_return_int(local, ret);
	return ret;
}

static inline int drv_set_cca_mode(struct ieee802154_local *local,
				   const struct wpan_phy_cca *cca)
{
	int ret;

	might_sleep();

	if (!local->ops->set_cca_mode) {
		WARN_ON(1);
		return -EOPNOTSUPP;
	}

	trace_802154_drv_set_cca_mode(local, cca);
	ret = local->ops->set_cca_mode(&local->hw, cca);
	trace_802154_drv_return_int(local, ret);
	return ret;
}

static inline int drv_set_lbt_mode(struct ieee802154_local *local, bool mode)
{
	int ret;

	might_sleep();

	if (!local->ops->set_lbt) {
		WARN_ON(1);
		return -EOPNOTSUPP;
	}

	trace_802154_drv_set_lbt_mode(local, mode);
	ret = local->ops->set_lbt(&local->hw, mode);
	trace_802154_drv_return_int(local, ret);
	return ret;
}

static inline int
drv_set_cca_ed_level(struct ieee802154_local *local, s32 mbm)
{
	int ret;

	might_sleep();

	if (!local->ops->set_cca_ed_level) {
		WARN_ON(1);
		return -EOPNOTSUPP;
	}

	trace_802154_drv_set_cca_ed_level(local, mbm);
	ret = local->ops->set_cca_ed_level(&local->hw, mbm);
	trace_802154_drv_return_int(local, ret);
	return ret;
}

static inline int drv_set_pan_id(struct ieee802154_local *local, __le16 pan_id)
{
	struct ieee802154_hw_addr_filt filt;
	int ret;

	might_sleep();

	if (!local->ops->set_hw_addr_filt) {
		WARN_ON(1);
		return -EOPNOTSUPP;
	}

	filt.pan_id = pan_id;

	trace_802154_drv_set_pan_id(local, pan_id);
	ret = local->ops->set_hw_addr_filt(&local->hw, &filt,
					    IEEE802154_AFILT_PANID_CHANGED);
	trace_802154_drv_return_int(local, ret);
	return ret;
}

static inline int
drv_set_extended_addr(struct ieee802154_local *local, __le64 extended_addr)
{
	struct ieee802154_hw_addr_filt filt;
	int ret;

	might_sleep();

	if (!local->ops->set_hw_addr_filt) {
		WARN_ON(1);
		return -EOPNOTSUPP;
	}

	filt.ieee_addr = extended_addr;

	trace_802154_drv_set_extended_addr(local, extended_addr);
	ret = local->ops->set_hw_addr_filt(&local->hw, &filt,
					    IEEE802154_AFILT_IEEEADDR_CHANGED);
	trace_802154_drv_return_int(local, ret);
	return ret;
}

static inline int
drv_set_short_addr(struct ieee802154_local *local, __le16 short_addr)
{
	struct ieee802154_hw_addr_filt filt;
	int ret;

	might_sleep();

	if (!local->ops->set_hw_addr_filt) {
		WARN_ON(1);
		return -EOPNOTSUPP;
	}

	filt.short_addr = short_addr;

	trace_802154_drv_set_short_addr(local, short_addr);
	ret = local->ops->set_hw_addr_filt(&local->hw, &filt,
					    IEEE802154_AFILT_SADDR_CHANGED);
	trace_802154_drv_return_int(local, ret);
	return ret;
}

static inline int
drv_set_pan_coord(struct ieee802154_local *local, bool is_coord)
{
	struct ieee802154_hw_addr_filt filt;
	int ret;

	might_sleep();

	if (!local->ops->set_hw_addr_filt) {
		WARN_ON(1);
		return -EOPNOTSUPP;
	}

	filt.pan_coord = is_coord;

	trace_802154_drv_set_pan_coord(local, is_coord);
	ret = local->ops->set_hw_addr_filt(&local->hw, &filt,
					    IEEE802154_AFILT_PANC_CHANGED);
	trace_802154_drv_return_int(local, ret);
	return ret;
}

static inline int
drv_set_csma_params(struct ieee802154_local *local, u8 min_be, u8 max_be,
		    u8 max_csma_backoffs)
{
	int ret;

	might_sleep();

	if (!local->ops->set_csma_params) {
		WARN_ON(1);
		return -EOPNOTSUPP;
	}

	trace_802154_drv_set_csma_params(local, min_be, max_be,
					 max_csma_backoffs);
	ret = local->ops->set_csma_params(&local->hw, min_be, max_be,
					   max_csma_backoffs);
	trace_802154_drv_return_int(local, ret);
	return ret;
}

static inline int
drv_set_max_frame_retries(struct ieee802154_local *local, s8 max_frame_retries)
{
	int ret;

	might_sleep();

	if (!local->ops->set_frame_retries) {
		WARN_ON(1);
		return -EOPNOTSUPP;
	}

	trace_802154_drv_set_max_frame_retries(local, max_frame_retries);
	ret = local->ops->set_frame_retries(&local->hw, max_frame_retries);
	trace_802154_drv_return_int(local, ret);
	return ret;
}

static inline int
drv_set_promiscuous_mode(struct ieee802154_local *local, bool on)
{
	int ret;

	might_sleep();

	if (!local->ops->set_promiscuous_mode) {
		WARN_ON(1);
		return -EOPNOTSUPP;
	}

	trace_802154_drv_set_promiscuous_mode(local, on);
	ret = local->ops->set_promiscuous_mode(&local->hw, on);
	trace_802154_drv_return_int(local, ret);
	return ret;
}

#endif /* __MAC802154_DRIVER_OPS */
='commit-subject'>percpu-refcount: fix reference leak during percpu-atomic transition</div><div class='commit-msg'>percpu_ref_tryget() and percpu_ref_tryget_live() should return
"true" IFF they acquire a reference. But the return value from
atomic_long_inc_not_zero() is a long and may have high bits set,
e.g. PERCPU_COUNT_BIAS, and the return value of the tryget routines
is bool so the reference may actually be acquired but the routines
return "false" which results in a reference leak since the caller
assumes it does not need to do a corresponding percpu_ref_put().

This was seen when performing CPU hotplug during I/O, as hangs in
blk_mq_freeze_queue_wait where percpu_ref_kill (blk_mq_freeze_queue_start)
raced with percpu_ref_tryget (blk_mq_timeout_work).
Sample stack trace:

__switch_to+0x2c0/0x450
__schedule+0x2f8/0x970
schedule+0x48/0xc0
blk_mq_freeze_queue_wait+0x94/0x120
blk_mq_queue_reinit_work+0xb8/0x180
blk_mq_queue_reinit_prepare+0x84/0xa0
cpuhp_invoke_callback+0x17c/0x600
cpuhp_up_callbacks+0x58/0x150
_cpu_up+0xf0/0x1c0
do_cpu_up+0x120/0x150
cpu_subsys_online+0x64/0xe0
device_online+0xb4/0x120
online_store+0xb4/0xc0
dev_attr_store+0x68/0xa0
sysfs_kf_write+0x80/0xb0
kernfs_fop_write+0x17c/0x250
__vfs_write+0x6c/0x1e0
vfs_write+0xd0/0x270
SyS_write+0x6c/0x110
system_call+0x38/0xe0

Examination of the queue showed a single reference (no PERCPU_COUNT_BIAS,
and __PERCPU_REF_DEAD, __PERCPU_REF_ATOMIC set) and no requests.
However, conditions at the time of the race are count of PERCPU_COUNT_BIAS + 0
and __PERCPU_REF_DEAD and __PERCPU_REF_ATOMIC set.

The fix is to make the tryget routines use an actual boolean internally instead
of the atomic long result truncated to a int.

Fixes: e625305b3907 percpu-refcount: make percpu_ref based on longs instead of ints
Link: https://bugzilla.kernel.org/show_bug.cgi?id=190751
Signed-off-by: Douglas Miller &lt;dougmill@linux.vnet.ibm.com&gt;
Reviewed-by: Jens Axboe &lt;axboe@fb.com&gt;
Signed-off-by: Tejun Heo &lt;tj@kernel.org&gt;
Fixes: e625305b3907 ("percpu-refcount: make percpu_ref based on longs instead of ints")
Cc: stable@vger.kernel.org # v3.18+
</div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?id=966d2b04e070bc040319aaebfec09e0144dc3341'>Diffstat</a> (limited to 'include/crypto/internal')</div><table summary='diffstat' class='diffstat'>