mm: add wrapper function for writing word to kernel text space
Adds a function to encapsulate the locking, removal of write-protection,
word write, cache flush and invalidate and restoration
of write protection. This is a convenience function for callers
needing to update a word in kernel text space.
Change-Id: I9832f0ff659ddc62c55819af5318c94b70f5c11c
Signed-off-by: Neil Leeder <nleeder@codeaurora.org>
diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c
index 84a7e5c..0f79b76 100644
--- a/arch/arm/mm/mmu.c
+++ b/arch/arm/mm/mmu.c
@@ -1124,6 +1124,20 @@
}
#endif
+void mem_text_write_kernel_word(unsigned long *addr, unsigned long word)
+{
+ unsigned long flags;
+
+ mem_text_writeable_spinlock(&flags);
+ mem_text_address_writeable((unsigned long)addr);
+ *addr = word;
+ flush_icache_range((unsigned long)addr,
+ ((unsigned long)addr + sizeof(long)));
+ mem_text_address_restore();
+ mem_text_writeable_spinunlock(&flags);
+}
+EXPORT_SYMBOL(mem_text_write_kernel_word);
+
static void __init map_lowmem(void)
{
struct memblock_region *reg;