Merge tag 'loongarch-fixes-6.6-3' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson

Pull LoongArch fixes from Huacai ChenL
 "Fix 4-level pagetable building, disable WUC for pgprot_writecombine()
  like ioremap_wc(), use correct annotation for exception handlers, and
  a trivial cleanup"

* tag 'loongarch-fixes-6.6-3' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson:
  LoongArch: Disable WUC for pgprot_writecombine() like ioremap_wc()
  LoongArch: Replace kmap_atomic() with kmap_local_page() in copy_user_highpage()
  LoongArch: Export symbol invalid_pud_table for modules building
  LoongArch: Use SYM_CODE_* to annotate exception handlers

Author: torvalds

arch/loongarch/include/asm/io.h

@@ -52,10 +52,9 @@ static inline void __iomem *ioremap_prot(phys_addr_t offset, unsigned long size,
  * @offset:    bus address of the memory
  * @size:      size of the resource to map
  */
-extern pgprot_t pgprot_wc;
-
 #define ioremap_wc(offset, size)	\
-	ioremap_prot((offset), (size), pgprot_val(pgprot_wc))
+	ioremap_prot((offset), (size),	\
+		pgprot_val(wc_enabled ? PAGE_KERNEL_WUC : PAGE_KERNEL_SUC))
 
 #define ioremap_cache(offset, size)	\
 	ioremap_prot((offset), (size), pgprot_val(PAGE_KERNEL))

arch/loongarch/include/asm/linkage.h

@@ -33,4 +33,12 @@
 	.cfi_endproc;					\
 	SYM_END(name, SYM_T_FUNC)
 
+#define SYM_CODE_START(name)				\
+	SYM_START(name, SYM_L_GLOBAL, SYM_A_ALIGN)	\
+	.cfi_startproc;
+
+#define SYM_CODE_END(name)				\
+	.cfi_endproc;					\
+	SYM_END(name, SYM_T_NONE)
+
 #endif

arch/loongarch/include/asm/pgtable-bits.h

@@ -105,13 +105,15 @@ static inline pgprot_t pgprot_noncached(pgprot_t _prot)
 	return __pgprot(prot);
 }
 
+extern bool wc_enabled;
+
 #define pgprot_writecombine pgprot_writecombine
 
 static inline pgprot_t pgprot_writecombine(pgprot_t _prot)
 {
 	unsigned long prot = pgprot_val(_prot);
 
-	prot = (prot & ~_CACHE_MASK) | _CACHE_WUC;
+	prot = (prot & ~_CACHE_MASK) | (wc_enabled ? _CACHE_WUC : _CACHE_SUC);
 
 	return __pgprot(prot);
 }

arch/loongarch/kernel/entry.S

@@ -18,7 +18,7 @@
 	.text
 	.cfi_sections	.debug_frame
 	.align	5
-SYM_FUNC_START(handle_syscall)
+SYM_CODE_START(handle_syscall)
 	csrrd		t0, PERCPU_BASE_KS
 	la.pcrel	t1, kernelsp
 	add.d		t1, t1, t0
@@ -71,7 +71,7 @@ SYM_FUNC_START(handle_syscall)
 	bl		do_syscall
 
 	RESTORE_ALL_AND_RET
-SYM_FUNC_END(handle_syscall)
+SYM_CODE_END(handle_syscall)
 _ASM_NOKPROBE(handle_syscall)
 
 SYM_CODE_START(ret_from_fork)

arch/loongarch/kernel/genex.S

@@ -31,7 +31,7 @@ SYM_FUNC_START(__arch_cpu_idle)
 1:	jr	ra
 SYM_FUNC_END(__arch_cpu_idle)
 
-SYM_FUNC_START(handle_vint)
+SYM_CODE_START(handle_vint)
 	BACKUP_T0T1
 	SAVE_ALL
 	la_abs	t1, __arch_cpu_idle
@@ -46,11 +46,11 @@ SYM_FUNC_START(handle_vint)
 	la_abs	t0, do_vint
 	jirl	ra, t0, 0
 	RESTORE_ALL_AND_RET
-SYM_FUNC_END(handle_vint)
+SYM_CODE_END(handle_vint)
 
-SYM_FUNC_START(except_vec_cex)
+SYM_CODE_START(except_vec_cex)
 	b	cache_parity_error
-SYM_FUNC_END(except_vec_cex)
+SYM_CODE_END(except_vec_cex)
 
 	.macro	build_prep_badv
 	csrrd	t0, LOONGARCH_CSR_BADV
@@ -66,7 +66,7 @@ SYM_FUNC_END(except_vec_cex)
 
 	.macro	BUILD_HANDLER exception handler prep
 	.align	5
-	SYM_FUNC_START(handle_\exception)
+	SYM_CODE_START(handle_\exception)
 	666:
 	BACKUP_T0T1
 	SAVE_ALL
@@ -76,7 +76,7 @@ SYM_FUNC_END(except_vec_cex)
 	jirl	ra, t0, 0
 	668:
 	RESTORE_ALL_AND_RET
-	SYM_FUNC_END(handle_\exception)
+	SYM_CODE_END(handle_\exception)
 	SYM_DATA(unwind_hint_\exception, .word 668b - 666b)
 	.endm
 
@@ -93,7 +93,7 @@ SYM_FUNC_END(except_vec_cex)
 	BUILD_HANDLER watch watch none
 	BUILD_HANDLER reserved reserved none	/* others */
 
-SYM_FUNC_START(handle_sys)
+SYM_CODE_START(handle_sys)
 	la_abs	t0, handle_syscall
 	jr	t0
-SYM_FUNC_END(handle_sys)
+SYM_CODE_END(handle_sys)

arch/loongarch/kernel/setup.c

@@ -161,19 +161,19 @@ static void __init smbios_parse(void)
 }
 
 #ifdef CONFIG_ARCH_WRITECOMBINE
-pgprot_t pgprot_wc = PAGE_KERNEL_WUC;
+bool wc_enabled = true;
 #else
-pgprot_t pgprot_wc = PAGE_KERNEL_SUC;
+bool wc_enabled = false;
 #endif
 
-EXPORT_SYMBOL(pgprot_wc);
+EXPORT_SYMBOL(wc_enabled);
 
 static int __init setup_writecombine(char *p)
 {
 	if (!strcmp(p, "on"))
-		pgprot_wc = PAGE_KERNEL_WUC;
+		wc_enabled = true;
 	else if (!strcmp(p, "off"))
-		pgprot_wc = PAGE_KERNEL_SUC;
+		wc_enabled = false;
 	else
 		pr_warn("Unknown writecombine setting \"%s\".\n", p);
 

arch/loongarch/mm/init.c

@@ -43,11 +43,11 @@ void copy_user_highpage(struct page *to, struct page *from,
 {
 	void *vfrom, *vto;
 
-	vto = kmap_atomic(to);
-	vfrom = kmap_atomic(from);
+	vfrom = kmap_local_page(from);
+	vto = kmap_local_page(to);
 	copy_page(vto, vfrom);
-	kunmap_atomic(vfrom);
-	kunmap_atomic(vto);
+	kunmap_local(vfrom);
+	kunmap_local(vto);
 	/* Make sure this page is cleared on other CPU's too before using it */
 	smp_wmb();
 }
@@ -240,6 +240,7 @@ pgd_t swapper_pg_dir[_PTRS_PER_PGD] __section(".bss..swapper_pg_dir");
 pgd_t invalid_pg_dir[_PTRS_PER_PGD] __page_aligned_bss;
 #ifndef __PAGETABLE_PUD_FOLDED
 pud_t invalid_pud_table[PTRS_PER_PUD] __page_aligned_bss;
+EXPORT_SYMBOL(invalid_pud_table);
 #endif
 #ifndef __PAGETABLE_PMD_FOLDED
 pmd_t invalid_pmd_table[PTRS_PER_PMD] __page_aligned_bss;

arch/loongarch/mm/tlbex.S

@@ -17,21 +17,21 @@
 #define PTRS_PER_PTE_BITS	(PAGE_SHIFT - 3)
 
 	.macro tlb_do_page_fault, write
-	SYM_FUNC_START(tlb_do_page_fault_\write)
+	SYM_CODE_START(tlb_do_page_fault_\write)
 	SAVE_ALL
 	csrrd		a2, LOONGARCH_CSR_BADV
 	move		a0, sp
 	REG_S		a2, sp, PT_BVADDR
 	li.w		a1, \write
 	bl		do_page_fault
 	RESTORE_ALL_AND_RET
-	SYM_FUNC_END(tlb_do_page_fault_\write)
+	SYM_CODE_END(tlb_do_page_fault_\write)
 	.endm
 
 	tlb_do_page_fault 0
 	tlb_do_page_fault 1
 
-SYM_FUNC_START(handle_tlb_protect)
+SYM_CODE_START(handle_tlb_protect)
 	BACKUP_T0T1
 	SAVE_ALL
 	move		a0, sp
@@ -41,9 +41,9 @@ SYM_FUNC_START(handle_tlb_protect)
 	la_abs		t0, do_page_fault
 	jirl		ra, t0, 0
 	RESTORE_ALL_AND_RET
-SYM_FUNC_END(handle_tlb_protect)
+SYM_CODE_END(handle_tlb_protect)
 
-SYM_FUNC_START(handle_tlb_load)
+SYM_CODE_START(handle_tlb_load)
 	csrwr		t0, EXCEPTION_KS0
 	csrwr		t1, EXCEPTION_KS1
 	csrwr		ra, EXCEPTION_KS2
@@ -187,16 +187,16 @@ nopage_tlb_load:
 	csrrd		ra, EXCEPTION_KS2
 	la_abs		t0, tlb_do_page_fault_0
 	jr		t0
-SYM_FUNC_END(handle_tlb_load)
+SYM_CODE_END(handle_tlb_load)
 
-SYM_FUNC_START(handle_tlb_load_ptw)
+SYM_CODE_START(handle_tlb_load_ptw)
 	csrwr		t0, LOONGARCH_CSR_KS0
 	csrwr		t1, LOONGARCH_CSR_KS1
 	la_abs		t0, tlb_do_page_fault_0
 	jr		t0
-SYM_FUNC_END(handle_tlb_load_ptw)
+SYM_CODE_END(handle_tlb_load_ptw)
 
-SYM_FUNC_START(handle_tlb_store)
+SYM_CODE_START(handle_tlb_store)
 	csrwr		t0, EXCEPTION_KS0
 	csrwr		t1, EXCEPTION_KS1
 	csrwr		ra, EXCEPTION_KS2
@@ -343,16 +343,16 @@ nopage_tlb_store:
 	csrrd		ra, EXCEPTION_KS2
 	la_abs		t0, tlb_do_page_fault_1
 	jr		t0
-SYM_FUNC_END(handle_tlb_store)
+SYM_CODE_END(handle_tlb_store)
 
-SYM_FUNC_START(handle_tlb_store_ptw)
+SYM_CODE_START(handle_tlb_store_ptw)
 	csrwr		t0, LOONGARCH_CSR_KS0
 	csrwr		t1, LOONGARCH_CSR_KS1
 	la_abs		t0, tlb_do_page_fault_1
 	jr		t0
-SYM_FUNC_END(handle_tlb_store_ptw)
+SYM_CODE_END(handle_tlb_store_ptw)
 
-SYM_FUNC_START(handle_tlb_modify)
+SYM_CODE_START(handle_tlb_modify)
 	csrwr		t0, EXCEPTION_KS0
 	csrwr		t1, EXCEPTION_KS1
 	csrwr		ra, EXCEPTION_KS2
@@ -497,16 +497,16 @@ nopage_tlb_modify:
 	csrrd		ra, EXCEPTION_KS2
 	la_abs		t0, tlb_do_page_fault_1
 	jr		t0
-SYM_FUNC_END(handle_tlb_modify)
+SYM_CODE_END(handle_tlb_modify)
 
-SYM_FUNC_START(handle_tlb_modify_ptw)
+SYM_CODE_START(handle_tlb_modify_ptw)
 	csrwr		t0, LOONGARCH_CSR_KS0
 	csrwr		t1, LOONGARCH_CSR_KS1
 	la_abs		t0, tlb_do_page_fault_1
 	jr		t0
-SYM_FUNC_END(handle_tlb_modify_ptw)
+SYM_CODE_END(handle_tlb_modify_ptw)
 
-SYM_FUNC_START(handle_tlb_refill)
+SYM_CODE_START(handle_tlb_refill)
 	csrwr		t0, LOONGARCH_CSR_TLBRSAVE
 	csrrd		t0, LOONGARCH_CSR_PGD
 	lddir		t0, t0, 3
@@ -521,4 +521,4 @@ SYM_FUNC_START(handle_tlb_refill)
 	tlbfill
 	csrrd		t0, LOONGARCH_CSR_TLBRSAVE
 	ertn
-SYM_FUNC_END(handle_tlb_refill)
+SYM_CODE_END(handle_tlb_refill)