linux-kernel - [PATCH 02/33] powerpc/legacy_serial: cache serial port and info in add_legacy

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20250611100319.186924-3-jirislaby@kernel.org>
Date: Wed, 11 Jun 2025 12:02:48 +0200
From: "Jiri Slaby (SUSE)" <jirislaby@...nel.org>
To: gregkh@...uxfoundation.org
Cc: linux-serial@...r.kernel.org,
	linux-kernel@...r.kernel.org,
	"Jiri Slaby (SUSE)" <jirislaby@...nel.org>,
	Madhavan Srinivasan <maddy@...ux.ibm.com>,
	Michael Ellerman <mpe@...erman.id.au>,
	Nicholas Piggin <npiggin@...il.com>,
	Christophe Leroy <christophe.leroy@...roup.eu>,
	linuxppc-dev@...ts.ozlabs.org
Subject: [PATCH 02/33] powerpc/legacy_serial: cache serial port and info in add_legacy_port()

Caching the port and info in local variables makes the code more compact
and easier to understand.

Signed-off-by: Jiri Slaby (SUSE) <jirislaby@...nel.org>
Cc: Madhavan Srinivasan <maddy@...ux.ibm.com>
Cc: Michael Ellerman <mpe@...erman.id.au>
Cc: Nicholas Piggin <npiggin@...il.com>
Cc: Christophe Leroy <christophe.leroy@...roup.eu>
Cc: linuxppc-dev@...ts.ozlabs.org
---
 arch/powerpc/kernel/legacy_serial.c | 52 ++++++++++++++---------------
 1 file changed, 26 insertions(+), 26 deletions(-)

diff --git a/arch/powerpc/kernel/legacy_serial.c b/arch/powerpc/kernel/legacy_serial.c
index 1da2f6e7d2a1..d9080189c28c 100644
--- a/arch/powerpc/kernel/legacy_serial.c
+++ b/arch/powerpc/kernel/legacy_serial.c
@@ -77,6 +77,8 @@ static int __init add_legacy_port(struct device_node *np, int want_index,
 				  phys_addr_t taddr, unsigned long irq,
 				  upf_t flags, int irq_check_parent)
 {
+	struct plat_serial8250_port *legacy_port;
+	struct legacy_serial_info *legacy_info;
 	const __be32 *clk, *spd, *rs;
 	u32 clock = BASE_BAUD * 16;
 	u32 shift = 0;
@@ -110,16 +112,17 @@ static int __init add_legacy_port(struct device_node *np, int want_index,
 	if (index >= legacy_serial_count)
 		legacy_serial_count = index + 1;
 
+	legacy_port = &legacy_serial_ports[index];
+	legacy_info = &legacy_serial_infos[index];
+
 	/* Check if there is a port who already claimed our slot */
-	if (legacy_serial_infos[index].np != NULL) {
+	if (legacy_info->np != NULL) {
 		/* if we still have some room, move it, else override */
 		if (legacy_serial_count < MAX_LEGACY_SERIAL_PORTS) {
 			printk(KERN_DEBUG "Moved legacy port %d -> %d\n",
 			       index, legacy_serial_count);
-			legacy_serial_ports[legacy_serial_count] =
-				legacy_serial_ports[index];
-			legacy_serial_infos[legacy_serial_count] =
-				legacy_serial_infos[index];
+			legacy_serial_ports[legacy_serial_count] = *legacy_port;
+			legacy_serial_infos[legacy_serial_count] = *legacy_info;
 			legacy_serial_count++;
 		} else {
 			printk(KERN_DEBUG "Replacing legacy port %d\n", index);
@@ -127,36 +130,33 @@ static int __init add_legacy_port(struct device_node *np, int want_index,
 	}
 
 	/* Now fill the entry */
-	memset(&legacy_serial_ports[index], 0,
-	       sizeof(struct plat_serial8250_port));
+	memset(legacy_port, 0, sizeof(*legacy_port));
 	if (iotype == UPIO_PORT)
-		legacy_serial_ports[index].iobase = base;
+		legacy_port->iobase = base;
 	else
-		legacy_serial_ports[index].mapbase = base;
-
-	legacy_serial_ports[index].iotype = iotype;
-	legacy_serial_ports[index].uartclk = clock;
-	legacy_serial_ports[index].irq = irq;
-	legacy_serial_ports[index].flags = flags;
-	legacy_serial_ports[index].regshift = shift;
-	legacy_serial_infos[index].taddr = taddr;
-	legacy_serial_infos[index].np = of_node_get(np);
-	legacy_serial_infos[index].clock = clock;
-	legacy_serial_infos[index].speed = spd ? be32_to_cpup(spd) : 0;
-	legacy_serial_infos[index].irq_check_parent = irq_check_parent;
+		legacy_port->mapbase = base;
+
+	legacy_port->iotype = iotype;
+	legacy_port->uartclk = clock;
+	legacy_port->irq = irq;
+	legacy_port->flags = flags;
+	legacy_port->regshift = shift;
+	legacy_info->taddr = taddr;
+	legacy_info->np = of_node_get(np);
+	legacy_info->clock = clock;
+	legacy_info->speed = spd ? be32_to_cpup(spd) : 0;
+	legacy_info->irq_check_parent = irq_check_parent;
 
 	if (iotype == UPIO_TSI) {
-		legacy_serial_ports[index].serial_in = tsi_serial_in;
-		legacy_serial_ports[index].serial_out = tsi_serial_out;
+		legacy_port->serial_in = tsi_serial_in;
+		legacy_port->serial_out = tsi_serial_out;
 	}
 
-	printk(KERN_DEBUG "Found legacy serial port %d for %pOF\n",
-	       index, np);
+	printk(KERN_DEBUG "Found legacy serial port %d for %pOF\n", index, np);
 	printk(KERN_DEBUG "  %s=%llx, taddr=%llx, irq=%lx, clk=%d, speed=%d\n",
 	       (iotype == UPIO_PORT) ? "port" : "mem",
 	       (unsigned long long)base, (unsigned long long)taddr, irq,
-	       legacy_serial_ports[index].uartclk,
-	       legacy_serial_infos[index].speed);
+	       legacy_port->uartclk, legacy_info->speed);
 
 	return index;
 }
-- 
2.49.0