[PATCH v2 28/37] powerpc/nohash: Add _PAGE_WRITE to supplement _PAGE_RW
From: Christophe Leroy <hidden>
Date: 2023-09-25 18:35:02
Also in:
lkml
Subsystem:
linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Madhavan Srinivasan, Michael Ellerman, Linus Torvalds
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 <redacted>
---
arch/powerpc/include/asm/nohash/32/pte-40x.h | 2 ++
arch/powerpc/include/asm/nohash/32/pte-44x.h | 2 ++
arch/powerpc/include/asm/nohash/32/pte-85xx.h | 2 ++
arch/powerpc/include/asm/nohash/64/pgtable.h | 2 +-
arch/powerpc/include/asm/nohash/pgtable.h | 9 ++++++---
arch/powerpc/include/asm/nohash/pte-e500.h | 2 ++
arch/powerpc/kernel/head_40x.S | 12 ++++++------
arch/powerpc/kernel/head_44x.S | 4 ++--
arch/powerpc/kernel/head_85xx.S | 2 +-
arch/powerpc/mm/nohash/e500.c | 4 ++--
10 files changed, 26 insertions(+), 15 deletions(-)
diff --git a/arch/powerpc/include/asm/nohash/32/pte-40x.h b/arch/powerpc/include/asm/nohash/32/pte-40x.h
index 0b4e5f8ce3e8..e28ef0f5781e 100644
--- a/arch/powerpc/include/asm/nohash/32/pte-40x.h
+++ b/arch/powerpc/include/asm/nohash/32/pte-40x.h@@ -49,6 +49,8 @@ #define _PAGE_EXEC 0x200 /* hardware: EX permission */ #define _PAGE_ACCESSED 0x400 /* software: R: page referenced */ +#define _PAGE_WRITE _PAGE_RW + /* No page size encoding in the linux PTE */ #define _PAGE_PSIZE 0
diff --git a/arch/powerpc/include/asm/nohash/32/pte-44x.h b/arch/powerpc/include/asm/nohash/32/pte-44x.h
index b7ed13cee137..fc0c075006ea 100644
--- a/arch/powerpc/include/asm/nohash/32/pte-44x.h
+++ b/arch/powerpc/include/asm/nohash/32/pte-44x.h@@ -75,6 +75,8 @@ #define _PAGE_NO_CACHE 0x00000400 /* H: I bit */ #define _PAGE_WRITETHRU 0x00000800 /* H: W bit */ +#define _PAGE_WRITE _PAGE_RW + /* No page size encoding in the linux PTE */ #define _PAGE_PSIZE 0
diff --git a/arch/powerpc/include/asm/nohash/32/pte-85xx.h b/arch/powerpc/include/asm/nohash/32/pte-85xx.h
index 16451df5ddb0..462acf69e302 100644
--- a/arch/powerpc/include/asm/nohash/32/pte-85xx.h
+++ b/arch/powerpc/include/asm/nohash/32/pte-85xx.h@@ -31,6 +31,8 @@ #define _PAGE_WRITETHRU 0x00400 /* H: W bit */ #define _PAGE_SPECIAL 0x00800 /* S: Special page */ +#define _PAGE_WRITE _PAGE_RW + #define _PAGE_KERNEL_RO 0 #define _PAGE_KERNEL_ROX _PAGE_EXEC #define _PAGE_KERNEL_RW (_PAGE_DIRTY | _PAGE_RW)
diff --git a/arch/powerpc/include/asm/nohash/64/pgtable.h b/arch/powerpc/include/asm/nohash/64/pgtable.h
index 36b9bad428cc..2202c78730e8 100644
--- a/arch/powerpc/include/asm/nohash/64/pgtable.h
+++ b/arch/powerpc/include/asm/nohash/64/pgtable.h@@ -149,7 +149,7 @@ static inline void p4d_set(p4d_t *p4dp, unsigned long val) static inline void huge_ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr, pte_t *ptep) { - pte_update(mm, addr, ptep, _PAGE_RW, 0, 1); + pte_update(mm, addr, ptep, _PAGE_WRITE, 0, 1); } #define __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH
diff --git a/arch/powerpc/include/asm/nohash/pgtable.h b/arch/powerpc/include/asm/nohash/pgtable.h
index 200f2dbf48e2..ee677162f9e6 100644
--- a/arch/powerpc/include/asm/nohash/pgtable.h
+++ b/arch/powerpc/include/asm/nohash/pgtable.h@@ -84,7 +84,7 @@ static inline int ptep_test_and_clear_young(struct vm_area_struct *vma, 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); } #endif #define __HAVE_ARCH_PTEP_SET_WRPROTECT
@@ -123,6 +123,9 @@ static inline void __ptep_set_access_flags(struct vm_area_struct *vma, #ifndef pte_mkwrite_novma static inline pte_t pte_mkwrite_novma(pte_t pte) { + /* + * write implies read, hence set both + */ return __pte(pte_val(pte) | _PAGE_RW); } #endif
@@ -140,7 +143,7 @@ static inline pte_t pte_mkyoung(pte_t pte) #ifndef pte_wrprotect static inline pte_t pte_wrprotect(pte_t pte) { - return __pte(pte_val(pte) & ~_PAGE_RW); + return __pte(pte_val(pte) & ~_PAGE_WRITE); } #endif
@@ -154,7 +157,7 @@ static inline pte_t pte_mkexec(pte_t pte) #ifndef pte_write static inline int pte_write(pte_t pte) { - return pte_val(pte) & _PAGE_RW; + return pte_val(pte) & _PAGE_WRITE; } #endif #ifndef pte_read
diff --git a/arch/powerpc/include/asm/nohash/pte-e500.h b/arch/powerpc/include/asm/nohash/pte-e500.h
index 9f9e3f02d414..b775c7d465a4 100644
--- a/arch/powerpc/include/asm/nohash/pte-e500.h
+++ b/arch/powerpc/include/asm/nohash/pte-e500.h@@ -55,6 +55,8 @@ #define _PAGE_KERNEL_ROX (_PAGE_BAP_SR | _PAGE_BAP_SX) #define _PAGE_USER (_PAGE_BAP_UR | _PAGE_BAP_SR) /* Can be read */ +#define _PAGE_WRITE _PAGE_RW + #define _PAGE_SPECIAL _PAGE_SW0 /* Base page size */
diff --git a/arch/powerpc/kernel/head_40x.S b/arch/powerpc/kernel/head_40x.S
index b32e7b2ebdcf..9f92f5c5e6aa 100644
--- a/arch/powerpc/kernel/head_40x.S
+++ b/arch/powerpc/kernel/head_40x.S@@ -316,9 +316,9 @@ _ASM_NOKPROBE_SYMBOL(\name\()_virt) andc. r9, r9, r11 /* Check permission */ bne 5f - rlwinm r9, r11, 1, _PAGE_RW /* dirty => rw */ - and r9, r9, r11 /* hwwrite = dirty & rw */ - rlwimi r11, r9, 0, _PAGE_RW /* replace rw by hwwrite */ + rlwinm r9, r11, 1, _PAGE_WRITE /* dirty => w */ + and r9, r9, r11 /* hwwrite = dirty & w */ + rlwimi r11, r9, 0, _PAGE_WRITE /* replace w by hwwrite */ /* Create TLB tag. This is the faulting address plus a static * set of bits. These are size, valid, E, U0.
@@ -400,9 +400,9 @@ _ASM_NOKPROBE_SYMBOL(\name\()_virt) andc. r9, r9, r11 /* Check permission */ bne 5f - rlwinm r9, r11, 1, _PAGE_RW /* dirty => rw */ - and r9, r9, r11 /* hwwrite = dirty & rw */ - rlwimi r11, r9, 0, _PAGE_RW /* replace rw by hwwrite */ + rlwinm r9, r11, 1, _PAGE_WRITE /* dirty => w */ + and r9, r9, r11 /* hwwrite = dirty & w */ + rlwimi r11, r9, 0, _PAGE_WRITE /* replace w by hwwrite */ /* Create TLB tag. This is the faulting address plus a static * set of bits. These are size, valid, E, U0.
diff --git a/arch/powerpc/kernel/head_44x.S b/arch/powerpc/kernel/head_44x.S
index a3197c9f721c..858dabf84432 100644
--- a/arch/powerpc/kernel/head_44x.S
+++ b/arch/powerpc/kernel/head_44x.S@@ -342,7 +342,7 @@ interrupt_base: mtspr SPRN_MMUCR,r12 /* Mask of required permission bits. Note that while we - * do copy ESR:ST to _PAGE_RW position as trying to write + * do copy ESR:ST to _PAGE_WRITE position as trying to write * to an RO page is pretty common, we don't do it with * _PAGE_DIRTY. We could do it, but it's a fairly rare * event so I'd rather take the overhead when it happens
@@ -586,7 +586,7 @@ finish_tlb_load_44x: 4: mtspr SPRN_MMUCR,r12 /* Set MMUCR */ /* Mask of required permission bits. Note that while we - * do copy ESR:ST to _PAGE_RW position as trying to write + * do copy ESR:ST to _PAGE_WRITE position as trying to write * to an RO page is pretty common, we don't do it with * _PAGE_DIRTY. We could do it, but it's a fairly rare * event so I'd rather take the overhead when it happens
diff --git a/arch/powerpc/kernel/head_85xx.S b/arch/powerpc/kernel/head_85xx.S
index 97e9ea0c7297..594756a62c8e 100644
--- a/arch/powerpc/kernel/head_85xx.S
+++ b/arch/powerpc/kernel/head_85xx.S@@ -471,7 +471,7 @@ END_BTB_FLUSH_SECTION 4: /* Mask of required permission bits. Note that while we - * do copy ESR:ST to _PAGE_RW position as trying to write + * do copy ESR:ST to _PAGE_WRITE position as trying to write * to an RO page is pretty common, we don't do it with * _PAGE_DIRTY. We could do it, but it's a fairly rare * event so I'd rather take the overhead when it happens
diff --git a/arch/powerpc/mm/nohash/e500.c b/arch/powerpc/mm/nohash/e500.c
index 5b7d7a932bfd..921c3521ec11 100644
--- a/arch/powerpc/mm/nohash/e500.c
+++ b/arch/powerpc/mm/nohash/e500.c@@ -117,7 +117,7 @@ static void settlbcam(int index, unsigned long virt, phys_addr_t phys, TLBCAM[index].MAS2 |= (flags & _PAGE_ENDIAN) ? MAS2_E : 0; TLBCAM[index].MAS3 = (phys & MAS3_RPN) | MAS3_SR; - TLBCAM[index].MAS3 |= (flags & _PAGE_RW) ? MAS3_SW : 0; + TLBCAM[index].MAS3 |= (flags & _PAGE_WRITE) ? MAS3_SW : 0; if (mmu_has_feature(MMU_FTR_BIG_PHYS)) TLBCAM[index].MAS7 = (u64)phys >> 32;
@@ -125,7 +125,7 @@ static void settlbcam(int index, unsigned long virt, phys_addr_t phys, if (!is_kernel_addr(virt)) { TLBCAM[index].MAS3 |= MAS3_UR; TLBCAM[index].MAS3 |= (flags & _PAGE_EXEC) ? MAS3_UX : 0; - TLBCAM[index].MAS3 |= (flags & _PAGE_RW) ? MAS3_UW : 0; + TLBCAM[index].MAS3 |= (flags & _PAGE_WRITE) ? MAS3_UW : 0; } else { TLBCAM[index].MAS3 |= (flags & _PAGE_EXEC) ? MAS3_SX : 0; }
--
2.41.0