From 46ebef51fd92f52ba7dca21d3c4332e4127de515 Mon Sep 17 00:00:00 2001 From: Christophe Leroy Date: Mon, 25 Sep 2023 20:31:47 +0200 Subject: [PATCH] powerpc/32s: Add _PAGE_WRITE to supplement _PAGE_RW Several places, _PAGE_RW maps to write permission and don't always imply read. To make it more clear, do as book3s/64 in commit c7d54842deb1 ("powerpc/mm: Use _PAGE_READ to indicate Read access") and use _PAGE_WRITE when more relevant. For the time being _PAGE_WRITE is equivalent to _PAGE_RW but that will change when _PAGE_READ gets added in following patches. Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://msgid.link/5798782869fe4d2698f104948dabd17657b89395.1695659959.git.christophe.leroy@csgroup.eu --- arch/powerpc/include/asm/book3s/32/pgtable.h | 15 ++++++++++++--- arch/powerpc/kernel/head_book3s_32.S | 6 +++--- arch/powerpc/mm/book3s32/hash_low.S | 12 ++++++------ arch/powerpc/mm/book3s32/mmu.c | 2 +- 4 files changed, 22 insertions(+), 13 deletions(-) diff --git a/arch/powerpc/include/asm/book3s/32/pgtable.h b/arch/powerpc/include/asm/book3s/32/pgtable.h index 80505915c77c..480ad6b4fd6f 100644 --- a/arch/powerpc/include/asm/book3s/32/pgtable.h +++ b/arch/powerpc/include/asm/book3s/32/pgtable.h @@ -31,6 +31,8 @@ #define _PAGE_RW 0x400 /* software: user write access allowed */ #define _PAGE_SPECIAL 0x800 /* software: Special page */ +#define _PAGE_WRITE _PAGE_RW + #ifdef CONFIG_PTE_64BIT /* We never clear the high word of the pte */ #define _PTE_NONE_MASK (0xffffffff00000000ULL | _PAGE_HASHPTE) @@ -347,7 +349,7 @@ static inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr, static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr, pte_t *ptep) { - pte_update(mm, addr, ptep, _PAGE_RW, 0, 0); + pte_update(mm, addr, ptep, _PAGE_WRITE, 0, 0); } static inline void __ptep_set_access_flags(struct vm_area_struct *vma, @@ -406,7 +408,11 @@ static inline pte_t pte_swp_clear_exclusive(pte_t pte) } /* Generic accessors to PTE bits */ -static inline int pte_write(pte_t pte) { return !!(pte_val(pte) & _PAGE_RW);} +static inline bool pte_write(pte_t pte) +{ + return !!(pte_val(pte) & _PAGE_WRITE); +} + static inline int pte_read(pte_t pte) { return 1; } static inline int pte_dirty(pte_t pte) { return !!(pte_val(pte) & _PAGE_DIRTY); } static inline int pte_young(pte_t pte) { return !!(pte_val(pte) & _PAGE_ACCESSED); } @@ -469,7 +475,7 @@ static inline pte_t pfn_pte(unsigned long pfn, pgprot_t pgprot) /* Generic modifiers for PTE bits */ static inline pte_t pte_wrprotect(pte_t pte) { - return __pte(pte_val(pte) & ~_PAGE_RW); + return __pte(pte_val(pte) & ~_PAGE_WRITE); } static inline pte_t pte_exprotect(pte_t pte) @@ -499,6 +505,9 @@ static inline pte_t pte_mkpte(pte_t pte) static inline pte_t pte_mkwrite_novma(pte_t pte) { + /* + * write implies read, hence set both + */ return __pte(pte_val(pte) | _PAGE_RW); } diff --git a/arch/powerpc/kernel/head_book3s_32.S b/arch/powerpc/kernel/head_book3s_32.S index 6764b98ca360..615d429d7bd1 100644 --- a/arch/powerpc/kernel/head_book3s_32.S +++ b/arch/powerpc/kernel/head_book3s_32.S @@ -503,9 +503,9 @@ DataLoadTLBMiss: andc. r1,r1,r0 /* check access & ~permission */ bne- DataAddressInvalid /* return if access not permitted */ /* Convert linux-style PTE to low word of PPC-style PTE */ - rlwinm r1,r0,32-9,30,30 /* _PAGE_RW -> PP msb */ + rlwinm r1,r0,32-9,30,30 /* _PAGE_WRITE -> PP msb */ rlwimi r0,r0,32-1,30,30 /* _PAGE_USER -> PP msb */ - rlwimi r1,r0,32-3,24,24 /* _PAGE_RW -> _PAGE_DIRTY */ + rlwimi r1,r0,32-3,24,24 /* _PAGE_WRITE -> _PAGE_DIRTY */ rlwimi r0,r0,32-1,31,31 /* _PAGE_USER -> PP lsb */ xori r1,r1,_PAGE_DIRTY /* clear dirty when not rw */ ori r1,r1,0xe04 /* clear out reserved bits */ @@ -689,7 +689,7 @@ hash_page_dsi: mfdar r4 mfsrr0 r5 mfsrr1 r9 - rlwinm r3, r3, 32 - 15, _PAGE_RW /* DSISR_STORE -> _PAGE_RW */ + rlwinm r3, r3, 32 - 15, _PAGE_WRITE /* DSISR_STORE -> _PAGE_WRITE */ bl hash_page mfspr r10, SPRN_SPRG_THREAD restore_regs_thread r10 diff --git a/arch/powerpc/mm/book3s32/hash_low.S b/arch/powerpc/mm/book3s32/hash_low.S index 8b804e1a9fa4..acb0584c174c 100644 --- a/arch/powerpc/mm/book3s32/hash_low.S +++ b/arch/powerpc/mm/book3s32/hash_low.S @@ -37,7 +37,7 @@ /* * Load a PTE into the hash table, if possible. * The address is in r4, and r3 contains an access flag: - * _PAGE_RW (0x400) if a write. + * _PAGE_WRITE (0x400) if a write. * r9 contains the SRR1 value, from which we use the MSR_PR bit. * SPRG_THREAD contains the physical address of the current task's thread. * @@ -113,15 +113,15 @@ _GLOBAL(hash_page) lwarx r6,0,r8 /* get linux-style pte, flag word */ #ifdef CONFIG_PPC_KUAP mfsrin r5,r4 - rlwinm r0,r9,28,_PAGE_RW /* MSR[PR] => _PAGE_RW */ - rlwinm r5,r5,12,_PAGE_RW /* Ks => _PAGE_RW */ + rlwinm r0,r9,28,_PAGE_WRITE /* MSR[PR] => _PAGE_WRITE */ + rlwinm r5,r5,12,_PAGE_WRITE /* Ks => _PAGE_WRITE */ andc r5,r5,r0 /* Ks & ~MSR[PR] */ - andc r5,r6,r5 /* Clear _PAGE_RW when Ks = 1 && MSR[PR] = 0 */ + andc r5,r6,r5 /* Clear _PAGE_WRITE when Ks = 1 && MSR[PR] = 0 */ andc. r5,r3,r5 /* check access & ~permission */ #else andc. r5,r3,r6 /* check access & ~permission */ #endif - rlwinm r0,r3,32-3,24,24 /* _PAGE_RW access -> _PAGE_DIRTY */ + rlwinm r0,r3,32-3,24,24 /* _PAGE_WRITE access -> _PAGE_DIRTY */ ori r0,r0,_PAGE_ACCESSED|_PAGE_HASHPTE #ifdef CONFIG_SMP bne- .Lhash_page_out /* return if access not permitted */ @@ -307,7 +307,7 @@ Hash_msk = (((1 << Hash_bits) - 1) * 64) __REF _GLOBAL(create_hpte) /* Convert linux-style PTE (r5) to low word of PPC-style PTE (r8) */ - rlwinm r8,r5,32-9,30,30 /* _PAGE_RW -> PP msb */ + rlwinm r8,r5,32-9,30,30 /* _PAGE_WRITE -> PP msb */ rlwinm r0,r5,32-6,30,30 /* _PAGE_DIRTY -> PP msb */ and r8,r8,r0 /* writable if _RW & _DIRTY */ rlwimi r5,r5,32-1,30,30 /* _PAGE_USER -> PP msb */ diff --git a/arch/powerpc/mm/book3s32/mmu.c b/arch/powerpc/mm/book3s32/mmu.c index d1041c946ce2..5445587bfe84 100644 --- a/arch/powerpc/mm/book3s32/mmu.c +++ b/arch/powerpc/mm/book3s32/mmu.c @@ -277,7 +277,7 @@ void __init setbat(int index, unsigned long virt, phys_addr_t phys, /* Do DBAT first */ wimgxpp = flags & (_PAGE_WRITETHRU | _PAGE_NO_CACHE | _PAGE_COHERENT | _PAGE_GUARDED); - wimgxpp |= (flags & _PAGE_RW)? BPP_RW: BPP_RX; + wimgxpp |= (flags & _PAGE_WRITE) ? BPP_RW : BPP_RX; bat[1].batu = virt | (bl << 2) | 2; /* Vs=1, Vp=0 */ bat[1].batl = BAT_PHYS_ADDR(phys) | wimgxpp; if (!is_kernel_addr(virt))