[PATCH 1/4] serial: pch: replace __get_free_page() with kmalloc()

[Mike Rapoport (Microsoft)]

pch_uart_init_port() allocates a staging buffer for non-DMA receive path
using __get_free_page().

This buffer can be allocated with kmalloc() as there's nothing special
about it to go directly to the page allocator.

kmalloc() provides a better API that does not require ugly casts and
kfree() does not need to know the size of the freed object.

Replace use of __get_free_page() with kmalloc() and free_page() with
kfree().

Link: https://lore.kernel.org/all/635405e4-9423-4a25-a6e7-e03c8ea0bcbe@xxxxxxxxxx
Signed-off-by: Mike Rapoport (Microsoft) <rppt@xxxxxxxxxx>
---
 drivers/tty/serial/pch_uart.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/tty/serial/pch_uart.c b/drivers/tty/serial/pch_uart.c
index 6729d8e83c3c..07d8cdb58912 100644
--- a/drivers/tty/serial/pch_uart.c
+++ b/drivers/tty/serial/pch_uart.c
@@ -1655,7 +1655,7 @@ static struct eg20t_port *pch_uart_init_port(struct pci_dev *pdev,
 	if (priv == NULL)
 		goto init_port_alloc_err;
 
-	rxbuf = (unsigned char *)__get_free_page(GFP_KERNEL);
+	rxbuf = kmalloc(PAGE_SIZE, GFP_KERNEL);
 	if (!rxbuf)
 		goto init_port_free_txbuf;
 
@@ -1728,7 +1728,7 @@ static struct eg20t_port *pch_uart_init_port(struct pci_dev *pdev,
 #ifdef CONFIG_SERIAL_PCH_UART_CONSOLE
 	pch_uart_ports[board->line_no] = NULL;
 #endif
-	free_page((unsigned long)rxbuf);
+	kfree(rxbuf);
 init_port_free_txbuf:
 	kfree(priv);
 init_port_alloc_err:
@@ -1743,7 +1743,7 @@ static void pch_uart_exit_port(struct eg20t_port *priv)
 	snprintf(name, sizeof(name), "uart%d_regs", priv->port.line);
 	debugfs_lookup_and_remove(name, NULL);
 	uart_remove_one_port(&pch_uart_driver, &priv->port);
-	free_page((unsigned long)priv->rxbuf.buf);
+	kfree(priv->rxbuf.buf);
 }
 
 static void pch_uart_pci_remove(struct pci_dev *pdev)

-- 
2.53.0