arm64/mm: export contpte symbols only to GPL users

Patch series "Address some contpte nits".

These 2 patches address some nits raised by Catalin late in the review cycle for
my contpte series [1].

[1] https://lore.kernel.org/linux-mm/20240215103205.2607016-1-ryan.roberts@arm.com/

This patch (of 2):

The contpte symbols must be exported since some of the public inline
ptep_* APIs are called from modules and these inlines now call the contpte
functions.  Originally they were exported as EXPORT_SYMBOL() for fear of
breaking out-of-tree modules.  But we subsequently concluded that
EXPORT_SYMBOL_GPL() should be safe since these functions are deeply core
mm routines, and any module operating at this level is not going to be
able to survive on EXPORT_SYMBOL alone.

Link: https://lkml.kernel.org/r/20240226120321.1055731-1-ryan.roberts@arm.com
Link: https://lore.kernel.org/linux-mm/f9fc2b31-11cb-4969-8961-9c89fea41b74@nvidia.com/
Link: https://lkml.kernel.org/r/20240226120321.1055731-2-ryan.roberts@arm.comSigned-off-by: Ryan Roberts <ryan.roberts@arm.com>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

arch/arm64/mm/contpte.c

@@ -135,7 +135,7 @@ void __contpte_try_fold(struct mm_struct *mm, unsigned long addr,
 	pte = pte_mkcont(pte);
 	contpte_convert(mm, addr, orig_ptep, pte);
 }
-EXPORT_SYMBOL(__contpte_try_fold);
+EXPORT_SYMBOL_GPL(__contpte_try_fold);
 
 void __contpte_try_unfold(struct mm_struct *mm, unsigned long addr,
 			pte_t *ptep, pte_t pte)
@@ -150,7 +150,7 @@ void __contpte_try_unfold(struct mm_struct *mm, unsigned long addr,
 	pte = pte_mknoncont(pte);
 	contpte_convert(mm, addr, ptep, pte);
 }
-EXPORT_SYMBOL(__contpte_try_unfold);
+EXPORT_SYMBOL_GPL(__contpte_try_unfold);
 
 pte_t contpte_ptep_get(pte_t *ptep, pte_t orig_pte)
 {
@@ -178,7 +178,7 @@ pte_t contpte_ptep_get(pte_t *ptep, pte_t orig_pte)
 
 	return orig_pte;
 }
-EXPORT_SYMBOL(contpte_ptep_get);
+EXPORT_SYMBOL_GPL(contpte_ptep_get);
 
 pte_t contpte_ptep_get_lockless(pte_t *orig_ptep)
 {
@@ -231,7 +231,7 @@ pte_t contpte_ptep_get_lockless(pte_t *orig_ptep)
 
 	return orig_pte;
 }
-EXPORT_SYMBOL(contpte_ptep_get_lockless);
+EXPORT_SYMBOL_GPL(contpte_ptep_get_lockless);
 
 void contpte_set_ptes(struct mm_struct *mm, unsigned long addr,
 					pte_t *ptep, pte_t pte, unsigned int nr)
@@ -274,7 +274,7 @@ void contpte_set_ptes(struct mm_struct *mm, unsigned long addr,
 
 	} while (addr != end);
 }
-EXPORT_SYMBOL(contpte_set_ptes);
+EXPORT_SYMBOL_GPL(contpte_set_ptes);
 
 void contpte_clear_full_ptes(struct mm_struct *mm, unsigned long addr,
 				pte_t *ptep, unsigned int nr, int full)
@@ -282,7 +282,7 @@ void contpte_clear_full_ptes(struct mm_struct *mm, unsigned long addr,
 	contpte_try_unfold_partial(mm, addr, ptep, nr);
 	__clear_full_ptes(mm, addr, ptep, nr, full);
 }
-EXPORT_SYMBOL(contpte_clear_full_ptes);
+EXPORT_SYMBOL_GPL(contpte_clear_full_ptes);
 
 pte_t contpte_get_and_clear_full_ptes(struct mm_struct *mm,
 				unsigned long addr, pte_t *ptep,
@@ -291,7 +291,7 @@ pte_t contpte_get_and_clear_full_ptes(struct mm_struct *mm,
 	contpte_try_unfold_partial(mm, addr, ptep, nr);
 	return __get_and_clear_full_ptes(mm, addr, ptep, nr, full);
 }
-EXPORT_SYMBOL(contpte_get_and_clear_full_ptes);
+EXPORT_SYMBOL_GPL(contpte_get_and_clear_full_ptes);
 
 int contpte_ptep_test_and_clear_young(struct vm_area_struct *vma,
 					unsigned long addr, pte_t *ptep)
@@ -316,7 +316,7 @@ int contpte_ptep_test_and_clear_young(struct vm_area_struct *vma,
 
 	return young;
 }
-EXPORT_SYMBOL(contpte_ptep_test_and_clear_young);
+EXPORT_SYMBOL_GPL(contpte_ptep_test_and_clear_young);
 
 int contpte_ptep_clear_flush_young(struct vm_area_struct *vma,
 					unsigned long addr, pte_t *ptep)
@@ -337,7 +337,7 @@ int contpte_ptep_clear_flush_young(struct vm_area_struct *vma,
 
 	return young;
 }
-EXPORT_SYMBOL(contpte_ptep_clear_flush_young);
+EXPORT_SYMBOL_GPL(contpte_ptep_clear_flush_young);
 
 void contpte_wrprotect_ptes(struct mm_struct *mm, unsigned long addr,
 					pte_t *ptep, unsigned int nr)
@@ -355,7 +355,7 @@ void contpte_wrprotect_ptes(struct mm_struct *mm, unsigned long addr,
 	contpte_try_unfold_partial(mm, addr, ptep, nr);
 	__wrprotect_ptes(mm, addr, ptep, nr);
 }
-EXPORT_SYMBOL(contpte_wrprotect_ptes);
+EXPORT_SYMBOL_GPL(contpte_wrprotect_ptes);
 
 int contpte_ptep_set_access_flags(struct vm_area_struct *vma,
 					unsigned long addr, pte_t *ptep,
@@ -401,4 +401,4 @@ int contpte_ptep_set_access_flags(struct vm_area_struct *vma,
 
 	return 1;
 }
-EXPORT_SYMBOL(contpte_ptep_set_access_flags);
+EXPORT_SYMBOL_GPL(contpte_ptep_set_access_flags);