MIPS: SMP: Constify smp ops

smp_ops providers do not modify their ops structures, so they should be
made const for robustness. Since currently the MIPS kernel is not mapped
with memory protection, this does not in itself provide any security
benefit, but it still makes sense to make this change.

There are also slight code size efficincies from the structure being
made read-only, saving 128 bytes of kernel text on a
pistachio_defconfig.
Before:
   text	   data	    bss	    dec	    hex	filename
7187239	1772752	 470224	9430215	 8fe4c7	vmlinux
After:
   text	   data	    bss	    dec	    hex	filename
7187111	1772752	 470224	9430087	 8fe447	vmlinux

Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Marcin Nowakowski <marcin.nowakowski@imgtec.com>
Cc: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Kevin Cernekee <cernekee@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Doug Ledford <dledford@redhat.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Joe Perches <joe@perches.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Steven J. Hill <steven.hill@cavium.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16784/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

diff --git a/arch/mips/cavium-octeon/smp.c b/arch/mips/cavium-octeon/smp.c
index 3de786545ded10ac64f5fa77d2025fa3a9955fd9..163663a5363de3dc455751ddc4d2f6dda19782c9 100644 (file)
--- a/arch/mips/cavium-octeon/smp.c
+++ b/arch/mips/cavium-octeon/smp.c
@@ -408,7 +408,7 @@ late_initcall(register_cavium_notifier);
 
 #endif /* CONFIG_HOTPLUG_CPU */
 
-struct plat_smp_ops octeon_smp_ops = {
+const struct plat_smp_ops octeon_smp_ops = {
        .send_ipi_single        = octeon_send_ipi_single,
        .send_ipi_mask          = octeon_send_ipi_mask,
        .init_secondary         = octeon_init_secondary,
@@ -485,7 +485,7 @@ static void octeon_78xx_send_ipi_mask(const struct cpumask *mask,
                octeon_78xx_send_ipi_single(cpu, action);
 }
 
-static struct plat_smp_ops octeon_78xx_smp_ops = {
+static const struct plat_smp_ops octeon_78xx_smp_ops = {
        .send_ipi_single        = octeon_78xx_send_ipi_single,
        .send_ipi_mask          = octeon_78xx_send_ipi_mask,
        .init_secondary         = octeon_init_secondary,
@@ -501,7 +501,7 @@ static struct plat_smp_ops octeon_78xx_smp_ops = {
 
 void __init octeon_setup_smp(void)
 {
-       struct plat_smp_ops *ops;
+       const struct plat_smp_ops *ops;
 
        if (octeon_has_feature(OCTEON_FEATURE_CIU3))
                ops = &octeon_78xx_smp_ops;

diff --git a/arch/mips/fw/arc/init.c b/arch/mips/fw/arc/init.c
index 629b24db0d3a1f46a94d5ec402965e133a51c98d..008555969534236082ea61b1ecab5d627ff7a6d0 100644 (file)
--- a/arch/mips/fw/arc/init.c
+++ b/arch/mips/fw/arc/init.c
@@ -51,7 +51,7 @@ void __init prom_init(void)
 #endif
 #ifdef CONFIG_SGI_IP27
        {
-               extern struct plat_smp_ops ip27_smp_ops;
+               extern const struct plat_smp_ops ip27_smp_ops;
 
                register_smp_ops(&ip27_smp_ops);
        }

diff --git a/arch/mips/include/asm/bmips.h b/arch/mips/include/asm/bmips.h
index a92aee7b977acb56539f74f7f9db2d9d0c1291a5..b3e2975f83d36e021a57988672ef26c09701f879 100644 (file)
--- a/arch/mips/include/asm/bmips.h
+++ b/arch/mips/include/asm/bmips.h
@@ -48,8 +48,8 @@
 #include <asm/r4kcache.h>
 #include <asm/smp-ops.h>
 
-extern struct plat_smp_ops bmips43xx_smp_ops;
-extern struct plat_smp_ops bmips5000_smp_ops;
+extern const struct plat_smp_ops bmips43xx_smp_ops;
+extern const struct plat_smp_ops bmips5000_smp_ops;
 
 static inline int register_bmips_smp_ops(void)
 {

diff --git a/arch/mips/include/asm/mach-loongson64/loongson.h b/arch/mips/include/asm/mach-loongson64/loongson.h
index c68c0cc879c6b22756c0f20ea66d469ee56969b1..d0ae5d55413b68f48c8aaa3703bdb3217c9919c1 100644 (file)
--- a/arch/mips/include/asm/mach-loongson64/loongson.h
+++ b/arch/mips/include/asm/mach-loongson64/loongson.h
@@ -26,7 +26,7 @@ extern void mach_prepare_shutdown(void);
 /* environment arguments from bootloader */
 extern u32 cpu_clock_freq;
 extern u32 memsize, highmemsize;
-extern struct plat_smp_ops loongson3_smp_ops;
+extern const struct plat_smp_ops loongson3_smp_ops;
 
 /* loongson-specific command line, env and memory initialization */
 extern void __init prom_init_memory(void);

diff --git a/arch/mips/include/asm/netlogic/common.h b/arch/mips/include/asm/netlogic/common.h
index e0717d10e650fd0ebcbf734bf7f59ddb0954cc50..a6e6cbebe046e9631055ef3fdaa65ea720b71730 100644 (file)
--- a/arch/mips/include/asm/netlogic/common.h
+++ b/arch/mips/include/asm/netlogic/common.h
@@ -84,7 +84,7 @@ nlm_set_nmi_handler(void *handler)
  */
 void nlm_init_boot_cpu(void);
 unsigned int nlm_get_cpu_frequency(void);
-extern struct plat_smp_ops nlm_smp_ops;
+extern const struct plat_smp_ops nlm_smp_ops;
 extern char nlm_reset_entry[], nlm_reset_entry_end[];
 
 /* SWIOTLB */

diff --git a/arch/mips/include/asm/smp-ops.h b/arch/mips/include/asm/smp-ops.h
index db7c322f057f936d9c658498a5e7d397303efb09..38859e7b1f1f7124e7b81691c8f92033f5dd8587 100644 (file)
--- a/arch/mips/include/asm/smp-ops.h
+++ b/arch/mips/include/asm/smp-ops.h
@@ -35,11 +35,11 @@ struct plat_smp_ops {
 #endif
 };
 
-extern void register_smp_ops(struct plat_smp_ops *ops);
+extern void register_smp_ops(const struct plat_smp_ops *ops);
 
 static inline void plat_smp_setup(void)
 {
-       extern struct plat_smp_ops *mp_ops;     /* private */
+       extern const struct plat_smp_ops *mp_ops;       /* private */
 
        mp_ops->smp_setup();
 }
@@ -57,7 +57,7 @@ static inline void plat_smp_setup(void)
        /* UP, nothing to do ...  */
 }
 
-static inline void register_smp_ops(struct plat_smp_ops *ops)
+static inline void register_smp_ops(const struct plat_smp_ops *ops)
 {
 }
 
@@ -66,7 +66,7 @@ static inline void register_smp_ops(struct plat_smp_ops *ops)
 static inline int register_up_smp_ops(void)
 {
 #ifdef CONFIG_SMP_UP
-       extern struct plat_smp_ops up_smp_ops;
+       extern const struct plat_smp_ops up_smp_ops;
 
        register_smp_ops(&up_smp_ops);
 
@@ -79,7 +79,7 @@ static inline int register_up_smp_ops(void)
 static inline int register_cmp_smp_ops(void)
 {
 #ifdef CONFIG_MIPS_CMP
-       extern struct plat_smp_ops cmp_smp_ops;
+       extern const struct plat_smp_ops cmp_smp_ops;
 
        if (!mips_cm_present())
                return -ENODEV;
@@ -95,7 +95,7 @@ static inline int register_cmp_smp_ops(void)
 static inline int register_vsmp_smp_ops(void)
 {
 #ifdef CONFIG_MIPS_MT_SMP
-       extern struct plat_smp_ops vsmp_smp_ops;
+       extern const struct plat_smp_ops vsmp_smp_ops;
 
        register_smp_ops(&vsmp_smp_ops);
 

diff --git a/arch/mips/include/asm/smp.h b/arch/mips/include/asm/smp.h
index bab3d41e5987eea7c56af1e08563d65461eb61fb..9e494f8d9c03a13325bc135725ebfec45c01e24c 100644 (file)
--- a/arch/mips/include/asm/smp.h
+++ b/arch/mips/include/asm/smp.h
@@ -58,7 +58,7 @@ extern void calculate_cpu_foreign_map(void);
  */
 static inline void smp_send_reschedule(int cpu)
 {
-       extern struct plat_smp_ops *mp_ops;     /* private */
+       extern const struct plat_smp_ops *mp_ops;       /* private */
 
        mp_ops->send_ipi_single(cpu, SMP_RESCHEDULE_YOURSELF);
 }
@@ -66,14 +66,14 @@ static inline void smp_send_reschedule(int cpu)
 #ifdef CONFIG_HOTPLUG_CPU
 static inline int __cpu_disable(void)
 {
-       extern struct plat_smp_ops *mp_ops;     /* private */
+       extern const struct plat_smp_ops *mp_ops;       /* private */
 
        return mp_ops->cpu_disable();
 }
 
 static inline void __cpu_die(unsigned int cpu)
 {
-       extern struct plat_smp_ops *mp_ops;     /* private */
+       extern const struct plat_smp_ops *mp_ops;       /* private */
 
        mp_ops->cpu_die(cpu);
 }
@@ -97,14 +97,14 @@ int mips_smp_ipi_free(const struct cpumask *mask);
 
 static inline void arch_send_call_function_single_ipi(int cpu)
 {
-       extern struct plat_smp_ops *mp_ops;     /* private */
+       extern const struct plat_smp_ops *mp_ops;       /* private */
 
        mp_ops->send_ipi_mask(cpumask_of(cpu), SMP_CALL_FUNCTION);
 }
 
 static inline void arch_send_call_function_ipi_mask(const struct cpumask *mask)
 {
-       extern struct plat_smp_ops *mp_ops;     /* private */
+       extern const struct plat_smp_ops *mp_ops;       /* private */
 
        mp_ops->send_ipi_mask(mask, SMP_CALL_FUNCTION);
 }

diff --git a/arch/mips/kernel/smp-bmips.c b/arch/mips/kernel/smp-bmips.c
index 1b070a76fcdd4c2e5f62a84bfff8e40ad0a8721b..f86d755e3d758da0d8942bda263f36cdc4d3fe48 100644 (file)
--- a/arch/mips/kernel/smp-bmips.c
+++ b/arch/mips/kernel/smp-bmips.c
@@ -409,7 +409,7 @@ void __ref play_dead(void)
 
 #endif /* CONFIG_HOTPLUG_CPU */
 
-struct plat_smp_ops bmips43xx_smp_ops = {
+const struct plat_smp_ops bmips43xx_smp_ops = {
        .smp_setup              = bmips_smp_setup,
        .prepare_cpus           = bmips_prepare_cpus,
        .boot_secondary         = bmips_boot_secondary,
@@ -423,7 +423,7 @@ struct plat_smp_ops bmips43xx_smp_ops = {
 #endif
 };
 
-struct plat_smp_ops bmips5000_smp_ops = {
+const struct plat_smp_ops bmips5000_smp_ops = {
        .smp_setup              = bmips_smp_setup,
        .prepare_cpus           = bmips_prepare_cpus,
        .boot_secondary         = bmips_boot_secondary,

diff --git a/arch/mips/kernel/smp-cmp.c b/arch/mips/kernel/smp-cmp.c
index 76923349b4fe16135a97247734a9d803788ae5ca..1acffdee88f451797916cca970a41eb0d85c52f6 100644 (file)
--- a/arch/mips/kernel/smp-cmp.c
+++ b/arch/mips/kernel/smp-cmp.c
@@ -148,7 +148,7 @@ void __init cmp_prepare_cpus(unsigned int max_cpus)
 
 }
 
-struct plat_smp_ops cmp_smp_ops = {
+const struct plat_smp_ops cmp_smp_ops = {
        .send_ipi_single        = mips_smp_send_ipi_single,
        .send_ipi_mask          = mips_smp_send_ipi_mask,
        .init_secondary         = cmp_init_secondary,

diff --git a/arch/mips/kernel/smp-cps.c b/arch/mips/kernel/smp-cps.c
index f832e99ad4c3879052d924c88750c79c97dc0f78..a6b8700563c7fe2660a0deedec631136afb21c77 100644 (file)
--- a/arch/mips/kernel/smp-cps.c
+++ b/arch/mips/kernel/smp-cps.c
@@ -571,7 +571,7 @@ static void cps_cpu_die(unsigned int cpu)
 
 #endif /* CONFIG_HOTPLUG_CPU */
 
-static struct plat_smp_ops cps_smp_ops = {
+static const struct plat_smp_ops cps_smp_ops = {
        .smp_setup              = cps_smp_setup,
        .prepare_cpus           = cps_prepare_cpus,
        .boot_secondary         = cps_boot_secondary,
@@ -587,7 +587,7 @@ static struct plat_smp_ops cps_smp_ops = {
 
 bool mips_cps_smp_in_use(void)
 {
-       extern struct plat_smp_ops *mp_ops;
+       extern const struct plat_smp_ops *mp_ops;
        return mp_ops == &cps_smp_ops;
 }
 

diff --git a/arch/mips/kernel/smp-mt.c b/arch/mips/kernel/smp-mt.c
index ed6b4df583ea0d420e9db7c75267fa419a4c4c8f..004ff5e8a820fca5208a64d73de1847d4f93e09d 100644 (file)
--- a/arch/mips/kernel/smp-mt.c
+++ b/arch/mips/kernel/smp-mt.c
@@ -239,7 +239,7 @@ static void __init vsmp_prepare_cpus(unsigned int max_cpus)
        mips_mt_set_cpuoptions();
 }
 
-struct plat_smp_ops vsmp_smp_ops = {
+const struct plat_smp_ops vsmp_smp_ops = {
        .send_ipi_single        = mips_smp_send_ipi_single,
        .send_ipi_mask          = mips_smp_send_ipi_mask,
        .init_secondary         = vsmp_init_secondary,

diff --git a/arch/mips/kernel/smp-up.c b/arch/mips/kernel/smp-up.c
index 17878d71ef2bc9f5238c7062b0f09cd5d1ca644b..4cf015a624d14fac930f110f556bf312296fd0ad 100644 (file)
--- a/arch/mips/kernel/smp-up.c
+++ b/arch/mips/kernel/smp-up.c
@@ -63,7 +63,7 @@ static void up_cpu_die(unsigned int cpu)
 }
 #endif
 
-struct plat_smp_ops up_smp_ops = {
+const struct plat_smp_ops up_smp_ops = {
        .send_ipi_single        = up_send_ipi_single,
        .send_ipi_mask          = up_send_ipi_mask,
        .init_secondary         = up_init_secondary,

diff --git a/arch/mips/kernel/smp.c b/arch/mips/kernel/smp.c
index 6bace7695788fbc3b7663aeb353a08a3c45503af..20c1f9ac946af621b722d07e2c6bb5f3bb545bbc 100644 (file)
--- a/arch/mips/kernel/smp.c
+++ b/arch/mips/kernel/smp.c
@@ -146,10 +146,10 @@ void calculate_cpu_foreign_map(void)
                               &temp_foreign_map, &cpu_sibling_map[i]);
 }
 
-struct plat_smp_ops *mp_ops;
+const struct plat_smp_ops *mp_ops;
 EXPORT_SYMBOL(mp_ops);
 
-void register_smp_ops(struct plat_smp_ops *ops)
+void register_smp_ops(const struct plat_smp_ops *ops)
 {
        if (mp_ops)
                printk(KERN_WARNING "Overriding previously set SMP ops\n");

diff --git a/arch/mips/loongson64/loongson-3/smp.c b/arch/mips/loongson64/loongson-3/smp.c
index b7a355c3c40813b45aa29940471bfa7148aa643a..5b5a44f50b0b14992eff31a425e3193ea1c1f391 100644 (file)
--- a/arch/mips/loongson64/loongson-3/smp.c
+++ b/arch/mips/loongson64/loongson-3/smp.c
@@ -734,7 +734,7 @@ early_initcall(register_loongson3_notifier);
 
 #endif
 
-struct plat_smp_ops loongson3_smp_ops = {
+const struct plat_smp_ops loongson3_smp_ops = {
        .send_ipi_single = loongson3_send_ipi_single,
        .send_ipi_mask = loongson3_send_ipi_mask,
        .init_secondary = loongson3_init_secondary,

diff --git a/arch/mips/netlogic/common/smp.c b/arch/mips/netlogic/common/smp.c
index bddf1ef553a4f695d320d4f88eb7f28b079cec94..eac3f2950b144cb42f980a511d8373a6ac5b0d98 100644 (file)
--- a/arch/mips/netlogic/common/smp.c
+++ b/arch/mips/netlogic/common/smp.c
@@ -272,7 +272,7 @@ int nlm_wakeup_secondary_cpus(void)
        return 0;
 }
 
-struct plat_smp_ops nlm_smp_ops = {
+const struct plat_smp_ops nlm_smp_ops = {
        .send_ipi_single        = nlm_send_ipi_single,
        .send_ipi_mask          = nlm_send_ipi_mask,
        .init_secondary         = nlm_init_secondary,

diff --git a/arch/mips/paravirt/paravirt-smp.c b/arch/mips/paravirt/paravirt-smp.c
index 72eb1a56c64508c732ccf1d7965367b85cf1e867..b61b26ccf6019e8072d26ab6a822a16562957721 100644 (file)
--- a/arch/mips/paravirt/paravirt-smp.c
+++ b/arch/mips/paravirt/paravirt-smp.c
@@ -133,7 +133,7 @@ static void paravirt_prepare_cpus(unsigned int max_cpus)
        }
 }
 
-struct plat_smp_ops paravirt_smp_ops = {
+const struct plat_smp_ops paravirt_smp_ops = {
        .send_ipi_single        = paravirt_send_ipi_single,
        .send_ipi_mask          = paravirt_send_ipi_mask,
        .init_secondary         = paravirt_init_secondary,

diff --git a/arch/mips/paravirt/setup.c b/arch/mips/paravirt/setup.c
index cb8448b373a743f88f1e9a7ff6a592bf8f3b9bc0..d2ffec1409a734ac5d94bcb6513474c95ab8d46b 100644 (file)
--- a/arch/mips/paravirt/setup.c
+++ b/arch/mips/paravirt/setup.c
@@ -14,7 +14,7 @@
 #include <asm/smp-ops.h>
 #include <asm/time.h>
 
-extern struct plat_smp_ops paravirt_smp_ops;
+extern const struct plat_smp_ops paravirt_smp_ops;
 
 const char *get_system_type(void)
 {

diff --git a/arch/mips/sgi-ip27/ip27-smp.c b/arch/mips/sgi-ip27/ip27-smp.c
index 4cd47d23d81a76105b5a5fc21a768cc50d478879..85ee974a15825ee1398d5de0b87b4a1fba24bde9 100644 (file)
--- a/arch/mips/sgi-ip27/ip27-smp.c
+++ b/arch/mips/sgi-ip27/ip27-smp.c
@@ -231,7 +231,7 @@ static void __init ip27_prepare_cpus(unsigned int max_cpus)
        /* We already did everything necessary earlier */
 }
 
-struct plat_smp_ops ip27_smp_ops = {
+const struct plat_smp_ops ip27_smp_ops = {
        .send_ipi_single        = ip27_send_ipi_single,
        .send_ipi_mask          = ip27_send_ipi_mask,
        .init_secondary         = ip27_init_secondary,

diff --git a/arch/mips/sibyte/bcm1480/smp.c b/arch/mips/sibyte/bcm1480/smp.c
index d0e94ffcc1b8b8abb058920631c68b500efaa336..20091d5fe5a171a5732553dc34f6610d1707355f 100644 (file)
--- a/arch/mips/sibyte/bcm1480/smp.c
+++ b/arch/mips/sibyte/bcm1480/smp.c
@@ -157,7 +157,7 @@ static void __init bcm1480_prepare_cpus(unsigned int max_cpus)
 {
 }
 
-struct plat_smp_ops bcm1480_smp_ops = {
+const struct plat_smp_ops bcm1480_smp_ops = {
        .send_ipi_single        = bcm1480_send_ipi_single,
        .send_ipi_mask          = bcm1480_send_ipi_mask,
        .init_secondary         = bcm1480_init_secondary,

diff --git a/arch/mips/sibyte/common/cfe.c b/arch/mips/sibyte/common/cfe.c
index c1a11a11db7f71b0564d1195c9f95f1f556ebbbb..115399202eab18a252f8a304cfcf791836c3e95f 100644 (file)
--- a/arch/mips/sibyte/common/cfe.c
+++ b/arch/mips/sibyte/common/cfe.c
@@ -229,8 +229,8 @@ static int __init initrd_setup(char *str)
 
 #endif
 
-extern struct plat_smp_ops sb_smp_ops;
-extern struct plat_smp_ops bcm1480_smp_ops;
+extern const struct plat_smp_ops sb_smp_ops;
+extern const struct plat_smp_ops bcm1480_smp_ops;
 
 /*
  * prom_init is called just after the cpu type is determined, from setup_arch()

diff --git a/arch/mips/sibyte/sb1250/smp.c b/arch/mips/sibyte/sb1250/smp.c
index 0a4a2c3982d86dc6394b222c2632eace7cd83f56..46ce1298c27d3566e05e4612e046657a369daa1b 100644 (file)
--- a/arch/mips/sibyte/sb1250/smp.c
+++ b/arch/mips/sibyte/sb1250/smp.c
@@ -146,7 +146,7 @@ static void __init sb1250_prepare_cpus(unsigned int max_cpus)
 {
 }
 
-struct plat_smp_ops sb_smp_ops = {
+const struct plat_smp_ops sb_smp_ops = {
        .send_ipi_single        = sb1250_send_ipi_single,
        .send_ipi_mask          = sb1250_send_ipi_mask,
        .init_secondary         = sb1250_init_secondary,