From 81454b8405f24df8b24984698d62c5f560d01fe3 Mon Sep 17 00:00:00 2001 From: Sebastian Andrzej Siewior Date: Wed, 20 Jun 2018 21:36:48 +0200 Subject: [PATCH] zd1211rw: use irqsave() in USB's complete callback The USB completion callback does not disable interrupts while acquiring the lock. We want to remove the local_irq_disable() invocation from __usb_hcd_giveback_urb() and therefore it is required for the callback handler to disable the interrupts while acquiring the lock. The callback may be invoked either in IRQ or BH context depending on the USB host controller. Use the _irqsave() variant of the locking primitives. Cc: Daniel Drake Cc: Ulrich Kunitz Cc: Kalle Valo Cc: "David S. Miller" Cc: linux-wireless@vger.kernel.org Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Kalle Valo --- drivers/net/wireless/zydas/zd1211rw/zd_usb.c | 21 ++++++++++++--------- 1 file changed, 12 insertions(+), 9 deletions(-) diff --git a/drivers/net/wireless/zydas/zd1211rw/zd_usb.c b/drivers/net/wireless/zydas/zd1211rw/zd_usb.c index c30bf11..c2cda3a 100644 --- a/drivers/net/wireless/zydas/zd1211rw/zd_usb.c +++ b/drivers/net/wireless/zydas/zd1211rw/zd_usb.c @@ -371,25 +371,27 @@ static inline void handle_regs_int_override(struct urb *urb) { struct zd_usb *usb = urb->context; struct zd_usb_interrupt *intr = &usb->intr; + unsigned long flags; - spin_lock(&intr->lock); + spin_lock_irqsave(&intr->lock, flags); if (atomic_read(&intr->read_regs_enabled)) { atomic_set(&intr->read_regs_enabled, 0); intr->read_regs_int_overridden = 1; complete(&intr->read_regs.completion); } - spin_unlock(&intr->lock); + spin_unlock_irqrestore(&intr->lock, flags); } static inline void handle_regs_int(struct urb *urb) { struct zd_usb *usb = urb->context; struct zd_usb_interrupt *intr = &usb->intr; + unsigned long flags; int len; u16 int_num; ZD_ASSERT(in_interrupt()); - spin_lock(&intr->lock); + spin_lock_irqsave(&intr->lock, flags); int_num = le16_to_cpu(*(__le16 *)(urb->transfer_buffer+2)); if (int_num == CR_INTERRUPT) { @@ -425,7 +427,7 @@ static inline void handle_regs_int(struct urb *urb) } out: - spin_unlock(&intr->lock); + spin_unlock_irqrestore(&intr->lock, flags); /* CR_INTERRUPT might override read_reg too. */ if (int_num == CR_INTERRUPT && atomic_read(&intr->read_regs_enabled)) @@ -665,6 +667,7 @@ static void rx_urb_complete(struct urb *urb) struct zd_usb_rx *rx; const u8 *buffer; unsigned int length; + unsigned long flags; switch (urb->status) { case 0: @@ -693,14 +696,14 @@ static void rx_urb_complete(struct urb *urb) /* If there is an old first fragment, we don't care. */ dev_dbg_f(urb_dev(urb), "*** first fragment ***\n"); ZD_ASSERT(length <= ARRAY_SIZE(rx->fragment)); - spin_lock(&rx->lock); + spin_lock_irqsave(&rx->lock, flags); memcpy(rx->fragment, buffer, length); rx->fragment_length = length; - spin_unlock(&rx->lock); + spin_unlock_irqrestore(&rx->lock, flags); goto resubmit; } - spin_lock(&rx->lock); + spin_lock_irqsave(&rx->lock, flags); if (rx->fragment_length > 0) { /* We are on a second fragment, we believe */ ZD_ASSERT(length + rx->fragment_length <= @@ -710,9 +713,9 @@ static void rx_urb_complete(struct urb *urb) handle_rx_packet(usb, rx->fragment, rx->fragment_length + length); rx->fragment_length = 0; - spin_unlock(&rx->lock); + spin_unlock_irqrestore(&rx->lock, flags); } else { - spin_unlock(&rx->lock); + spin_unlock_irqrestore(&rx->lock, flags); handle_rx_packet(usb, buffer, length); } -- 2.7.4