ARM: KVM: Move the HYP code to its own section

In order to be able to spread the HYP code into multiple compilation
units, adopt a layout similar to that of arm64:
- the HYP text is emited in its own section (.hyp.text)
- two linker generated symbols are use to identify the boundaries
  of that section

No functionnal change.

Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

4 files changed, 19 insertions, 10 deletions

diff --git a/arch/arm/include/asm/kvm_asm.h b/arch/arm/include/asm/kvm_asm.h
index 194c91b610ff..fa2fd253974f 100644
--- a/arch/arm/include/asm/kvm_asm.h
+++ b/arch/arm/include/asm/kvm_asm.h
@@ -19,6 +19,8 @@
 #ifndef __ARM_KVM_ASM_H__
 #define __ARM_KVM_ASM_H__
 
+#include <asm/virt.h>
+
 /* 0 is reserved as an invalid value. */
 #define c0_MPIDR        1       /* MultiProcessor ID Register */
 #define c0_CSSELR       2       /* Cache Size Selection Register */
@@ -91,8 +93,8 @@ extern char __kvm_hyp_exit_end[];
 
 extern char __kvm_hyp_vector[];
 
-extern char __kvm_hyp_code_start[];
-extern char __kvm_hyp_code_end[];
+#define __kvm_hyp_code_start    __hyp_text_start
+#define __kvm_hyp_code_end      __hyp_text_end
 
 extern void __kvm_flush_vm_context(void);
 extern void __kvm_tlb_flush_vmid_ipa(struct kvm *kvm, phys_addr_t ipa);
diff --git a/arch/arm/include/asm/virt.h b/arch/arm/include/asm/virt.h
index 4371f45c5784..5fdbfea6defb 100644
--- a/arch/arm/include/asm/virt.h
+++ b/arch/arm/include/asm/virt.h
@@ -74,6 +74,10 @@ static inline bool is_hyp_mode_mismatched(void)
 {
         return !!(__boot_cpu_mode & BOOT_CPU_MODE_MISMATCH);
 }
+
+/* The section containing the hypervisor text */
+extern char __hyp_text_start[];
+extern char __hyp_text_end[];
 #endif
 
 #endif /* __ASSEMBLY__ */
diff --git a/arch/arm/kernel/vmlinux.lds.S b/arch/arm/kernel/vmlinux.lds.S
index 8b60fde5ce48..b4139cbbbdd9 100644
--- a/arch/arm/kernel/vmlinux.lds.S
+++ b/arch/arm/kernel/vmlinux.lds.S
@@ -18,6 +18,11 @@
         *(.proc.info.init)                                              \
         VMLINUX_SYMBOL(__proc_info_end) = .;
 
+#define HYPERVISOR_TEXT                                                 \
+        VMLINUX_SYMBOL(__hyp_text_start) = .;                           \
+        *(.hyp.text)                                                    \
+        VMLINUX_SYMBOL(__hyp_text_end) = .;
+
 #define IDMAP_TEXT                                                      \
         ALIGN_FUNCTION();                                               \
         VMLINUX_SYMBOL(__idmap_text_start) = .;                         \
@@ -108,6 +113,7 @@ SECTIONS
                         TEXT_TEXT
                         SCHED_TEXT
                         LOCK_TEXT
+                        HYPERVISOR_TEXT
                         KPROBES_TEXT
                         *(.gnu.warning)
                         *(.glue_7)
diff --git a/arch/arm/kvm/interrupts.S b/arch/arm/kvm/interrupts.S
index 900ef6dd8f72..9d9cb71df449 100644
--- a/arch/arm/kvm/interrupts.S
+++ b/arch/arm/kvm/interrupts.S
@@ -28,9 +28,7 @@
 #include "interrupts_head.S"
 
         .text
-
-__kvm_hyp_code_start:
-        .globl __kvm_hyp_code_start
+        .pushsection    .hyp.text, "ax"
 
 /********************************************************************
  * Flush per-VMID TLBs
@@ -314,8 +312,6 @@ THUMB(	orr	r2, r2, #PSR_T_BIT	)
         eret
 .endm
 
-        .text
-
         .align 5
 __kvm_hyp_vector:
         .globl __kvm_hyp_vector
@@ -511,10 +507,9 @@ hyp_fiq:
 
         .ltorg
 
-__kvm_hyp_code_end:
-        .globl  __kvm_hyp_code_end
+        .popsection
 
-        .section ".rodata"
+        .pushsection ".rodata"
 
 und_die_str:
         .ascii  "unexpected undefined exception in Hyp mode at: %#08x\n"
@@ -524,3 +519,5 @@ dabt_die_str:
         .ascii  "unexpected data abort in Hyp mode at: %#08x\n"
 svc_die_str:
         .ascii  "unexpected HVC/SVC trap in Hyp mode at: %#08x\n"
+
+        .popsection