125 lines
4.3 KiB
Diff
125 lines
4.3 KiB
Diff
From ad6ee8430287f4d453bdbe0870c897f3568cb50f Mon Sep 17 00:00:00 2001
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From: Thomas Gleixner <tglx@linutronix.de>
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Date: Thu, 14 Sep 2023 20:43:38 +0206
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Subject: [PATCH 047/196] serial: atmel: Use port lock wrappers
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When a serial port is used for kernel console output, then all
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modifications to the UART registers which are done from other contexts,
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e.g. getty, termios, are interference points for the kernel console.
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So far this has been ignored and the printk output is based on the
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principle of hope. The rework of the console infrastructure which aims to
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support threaded and atomic consoles, requires to mark sections which
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modify the UART registers as unsafe. This allows the atomic write function
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to make informed decisions and eventually to restore operational state. It
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also allows to prevent the regular UART code from modifying UART registers
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while printk output is in progress.
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All modifications of UART registers are guarded by the UART port lock,
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which provides an obvious synchronization point with the console
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infrastructure.
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To avoid adding this functionality to all UART drivers, wrap the
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spin_[un]lock*() invocations for uart_port::lock into helper functions
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which just contain the spin_[un]lock*() invocations for now. In a
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subsequent step these helpers will gain the console synchronization
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mechanisms.
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Converted with coccinelle. No functional change.
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Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
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Signed-off-by: John Ogness <john.ogness@linutronix.de>
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Link: https://lore.kernel.org/r/20230914183831.587273-22-john.ogness@linutronix.de
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Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
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---
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drivers/tty/serial/atmel_serial.c | 24 ++++++++++++------------
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1 file changed, 12 insertions(+), 12 deletions(-)
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diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c
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index 88cdafa5ac54..1946fafc3f3e 100644
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--- a/drivers/tty/serial/atmel_serial.c
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+++ b/drivers/tty/serial/atmel_serial.c
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@@ -861,7 +861,7 @@ static void atmel_complete_tx_dma(void *arg)
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struct dma_chan *chan = atmel_port->chan_tx;
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unsigned long flags;
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- spin_lock_irqsave(&port->lock, flags);
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+ uart_port_lock_irqsave(port, &flags);
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if (chan)
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dmaengine_terminate_all(chan);
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@@ -893,7 +893,7 @@ static void atmel_complete_tx_dma(void *arg)
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atmel_port->tx_done_mask);
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}
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- spin_unlock_irqrestore(&port->lock, flags);
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+ uart_port_unlock_irqrestore(port, flags);
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}
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static void atmel_release_tx_dma(struct uart_port *port)
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@@ -1711,9 +1711,9 @@ static void atmel_tasklet_rx_func(struct tasklet_struct *t)
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struct uart_port *port = &atmel_port->uart;
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/* The interrupt handler does not take the lock */
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- spin_lock(&port->lock);
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+ uart_port_lock(port);
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atmel_port->schedule_rx(port);
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- spin_unlock(&port->lock);
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+ uart_port_unlock(port);
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}
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static void atmel_tasklet_tx_func(struct tasklet_struct *t)
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@@ -1723,9 +1723,9 @@ static void atmel_tasklet_tx_func(struct tasklet_struct *t)
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struct uart_port *port = &atmel_port->uart;
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/* The interrupt handler does not take the lock */
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- spin_lock(&port->lock);
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+ uart_port_lock(port);
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atmel_port->schedule_tx(port);
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- spin_unlock(&port->lock);
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+ uart_port_unlock(port);
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}
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static void atmel_init_property(struct atmel_uart_port *atmel_port,
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@@ -2175,7 +2175,7 @@ static void atmel_set_termios(struct uart_port *port,
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} else
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mode |= ATMEL_US_PAR_NONE;
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- spin_lock_irqsave(&port->lock, flags);
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+ uart_port_lock_irqsave(port, &flags);
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port->read_status_mask = ATMEL_US_OVRE;
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if (termios->c_iflag & INPCK)
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@@ -2377,22 +2377,22 @@ static void atmel_set_termios(struct uart_port *port,
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else
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atmel_disable_ms(port);
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- spin_unlock_irqrestore(&port->lock, flags);
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+ uart_port_unlock_irqrestore(port, flags);
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}
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static void atmel_set_ldisc(struct uart_port *port, struct ktermios *termios)
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{
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if (termios->c_line == N_PPS) {
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port->flags |= UPF_HARDPPS_CD;
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- spin_lock_irq(&port->lock);
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+ uart_port_lock_irq(port);
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atmel_enable_ms(port);
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- spin_unlock_irq(&port->lock);
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+ uart_port_unlock_irq(port);
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} else {
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port->flags &= ~UPF_HARDPPS_CD;
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if (!UART_ENABLE_MS(port, termios->c_cflag)) {
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- spin_lock_irq(&port->lock);
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+ uart_port_lock_irq(port);
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atmel_disable_ms(port);
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- spin_unlock_irq(&port->lock);
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+ uart_port_unlock_irq(port);
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}
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}
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}
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--
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2.43.2
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