LoongArch: Adjust system call for 32BIT/64BIT

Adjust system call for both 32BIT and 64BIT, including: add the uapi
unistd_{32,64}.h and syscall_table_{32,64}.h inclusion, add sys_mmap2()
definition, change the system call entry routines, etc.

Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

Author: chenhuacai

arch/loongarch/include/asm/Kbuild

@@ -1,4 +1,5 @@
 # SPDX-License-Identifier: GPL-2.0
+syscall-y += syscall_table_32.h
 syscall-y += syscall_table_64.h
 generated-y += orc_hash.h
 

arch/loongarch/include/uapi/asm/Kbuild

@@ -1,2 +1,3 @@
 # SPDX-License-Identifier: GPL-2.0
+syscall-y += unistd_32.h
 syscall-y += unistd_64.h

arch/loongarch/include/uapi/asm/unistd.h

@@ -1,3 +1,9 @@
 /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
 
+#include <asm/bitsperlong.h>
+
+#if __BITS_PER_LONG == 32
+#include <asm/unistd_32.h>
+#else
 #include <asm/unistd_64.h>
+#endif

arch/loongarch/kernel/Makefile.syscalls

@@ -1,4 +1,5 @@
 # SPDX-License-Identifier: GPL-2.0
 
 # No special ABIs on loongarch so far
+syscall_abis_32 +=
 syscall_abis_64 +=

arch/loongarch/kernel/entry.S

@@ -23,24 +23,24 @@ SYM_CODE_START(handle_syscall)
 	UNWIND_HINT_UNDEFINED
 	csrrd		t0, PERCPU_BASE_KS
 	la.pcrel	t1, kernelsp
-	add.d		t1, t1, t0
+	PTR_ADD		t1, t1, t0
 	move		t2, sp
-	ld.d		sp, t1, 0
+	PTR_L		sp, t1, 0
 
-	addi.d		sp, sp, -PT_SIZE
+	PTR_ADDI	sp, sp, -PT_SIZE
 	cfi_st		t2, PT_R3
 	cfi_rel_offset	sp, PT_R3
-	st.d		zero, sp, PT_R0
+	LONG_S		zero, sp, PT_R0
 	csrrd		t2, LOONGARCH_CSR_PRMD
-	st.d		t2, sp, PT_PRMD
+	LONG_S		t2, sp, PT_PRMD
 	csrrd		t2, LOONGARCH_CSR_CRMD
-	st.d		t2, sp, PT_CRMD
+	LONG_S		t2, sp, PT_CRMD
 	csrrd		t2, LOONGARCH_CSR_EUEN
-	st.d		t2, sp, PT_EUEN
+	LONG_S		t2, sp, PT_EUEN
 	csrrd		t2, LOONGARCH_CSR_ECFG
-	st.d		t2, sp, PT_ECFG
+	LONG_S		t2, sp, PT_ECFG
 	csrrd		t2, LOONGARCH_CSR_ESTAT
-	st.d		t2, sp, PT_ESTAT
+	LONG_S		t2, sp, PT_ESTAT
 	cfi_st		ra, PT_R1
 	cfi_st		a0, PT_R4
 	cfi_st		a1, PT_R5
@@ -51,7 +51,7 @@ SYM_CODE_START(handle_syscall)
 	cfi_st		a6, PT_R10
 	cfi_st		a7, PT_R11
 	csrrd		ra, LOONGARCH_CSR_ERA
-	st.d		ra, sp, PT_ERA
+	LONG_S		ra, sp, PT_ERA
 	cfi_rel_offset	ra, PT_ERA
 
 	cfi_st		tp, PT_R2
@@ -67,7 +67,7 @@ SYM_CODE_START(handle_syscall)
 #endif
 
 	move		u0, t0
-	li.d		tp, ~_THREAD_MASK
+	LONG_LI		tp, ~_THREAD_MASK
 	and		tp, tp, sp
 
 	move		a0, sp

arch/loongarch/kernel/syscall.c

@@ -34,9 +34,22 @@ SYSCALL_DEFINE6(mmap, unsigned long, addr, unsigned long, len, unsigned long,
 	return ksys_mmap_pgoff(addr, len, prot, flags, fd, offset >> PAGE_SHIFT);
 }
 
+SYSCALL_DEFINE6(mmap2, unsigned long, addr, unsigned long, len, unsigned long,
+		 prot, unsigned long, flags, unsigned long, fd, unsigned long, offset)
+{
+	if (offset & (~PAGE_MASK >> 12))
+		return -EINVAL;
+
+	return ksys_mmap_pgoff(addr, len, prot, flags, fd, offset >> (PAGE_SHIFT - 12));
+}
+
 void *sys_call_table[__NR_syscalls] = {
 	[0 ... __NR_syscalls - 1] = sys_ni_syscall,
+#ifdef CONFIG_32BIT
+#include <asm/syscall_table_32.h>
+#else
 #include <asm/syscall_table_64.h>
+#endif
 };
 
 typedef long (*sys_call_fn)(unsigned long, unsigned long,