From patchwork series 426252

https://patchwork.ozlabs.org//project/linuxppc-dev/list/?series=426252
linuxppc · Oct 2, 2024 · b13bd84 · b13bd84
1 parent 7beb771
commit b13bd84
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Showing 11 changed files with 39 additions and 38 deletions.
diff --git a/arch/powerpc/include/asm/vdso/getrandom.h b/arch/powerpc/include/asm/vdso/getrandom.h
@@ -7,6 +7,8 @@
 
 #ifndef __ASSEMBLY__
 
+#include <asm/vdso_datapage.h>
+
 static __always_inline int do_syscall_3(const unsigned long _r0, const unsigned long _r3,
 					const unsigned long _r4, const unsigned long _r5)
 {
@@ -43,11 +45,20 @@ static __always_inline ssize_t getrandom_syscall(void *buffer, size_t len, unsig
 
 static __always_inline struct vdso_rng_data *__arch_get_vdso_rng_data(void)
 {
-	return NULL;
+	struct vdso_arch_data *data;
+
+	asm(
+		"	bcl	20, 31, .+4\n"
+		"0:	mflr	%0\n"
+		"	addis	%0, %0, (_vdso_datapage - 0b)@ha\n"
+		"	addi	%0, %0, (_vdso_datapage - 0b)@l\n"
+	: "=r" (data) :: "lr");
+
+	return &data->rng_data;
 }
 
 ssize_t __c_kernel_getrandom(void *buffer, size_t len, unsigned int flags, void *opaque_state,
-			     size_t opaque_len, const struct vdso_rng_data *vd);
+			     size_t opaque_len);
 
 #endif /* !__ASSEMBLY__ */
 

diff --git a/arch/powerpc/include/asm/vdso_datapage.h b/arch/powerpc/include/asm/vdso_datapage.h
@@ -82,8 +82,9 @@ struct vdso_arch_data {
 	__u32 syscall_map[SYSCALL_MAP_SIZE];	/* Map of syscalls  */
 	__u32 compat_syscall_map[SYSCALL_MAP_SIZE];	/* Map of compat syscalls */
 
-	struct vdso_data data[CS_BASES];
 	struct vdso_rng_data rng_data;
+
+	struct vdso_data data[CS_BASES] __aligned(1 << CONFIG_PAGE_SHIFT);
 };
 
 #else /* CONFIG_PPC64 */
@@ -95,8 +96,9 @@ struct vdso_arch_data {
 	__u64 tb_ticks_per_sec;		/* Timebase tics / sec		0x38 */
 	__u32 syscall_map[SYSCALL_MAP_SIZE]; /* Map of syscalls */
 	__u32 compat_syscall_map[0];	/* No compat syscalls on PPC32 */
-	struct vdso_data data[CS_BASES];
 	struct vdso_rng_data rng_data;
+
+	struct vdso_data data[CS_BASES] __aligned(1 << CONFIG_PAGE_SHIFT);
 };
 
 #endif /* CONFIG_PPC64 */
@@ -105,29 +107,17 @@ extern struct vdso_arch_data *vdso_data;
 
 #else /* __ASSEMBLY__ */
 
-.macro get_datapage ptr
+.macro get_datapage ptr offset=0
 	bcl	20, 31, .+4
 999:
 	mflr	\ptr
-	addis	\ptr, \ptr, (_vdso_datapage - 999b)@ha
-	addi	\ptr, \ptr, (_vdso_datapage - 999b)@l
+	addis	\ptr, \ptr, (_vdso_datapage - 999b + \offset)@ha
+	addi	\ptr, \ptr, (_vdso_datapage - 999b + \offset)@l
 .endm
 
 #include <asm/asm-offsets.h>
 #include <asm/page.h>
 
-.macro get_realdatapage ptr scratch
-	get_datapage \ptr
-#ifdef CONFIG_TIME_NS
-	lwz	\scratch, VDSO_CLOCKMODE_OFFSET(\ptr)
-	xoris	\scratch, \scratch, VDSO_CLOCKMODE_TIMENS@h
-	xori	\scratch, \scratch, VDSO_CLOCKMODE_TIMENS@l
-	cntlzw	\scratch, \scratch
-	rlwinm	\scratch, \scratch, PAGE_SHIFT - 5, 1 << PAGE_SHIFT
-	add	\ptr, \ptr, \scratch
-#endif
-.endm
-
 #endif /* __ASSEMBLY__ */
 
 #endif /* __KERNEL__ */

diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c
@@ -335,7 +335,6 @@ int main(void)
 
 	/* datapage offsets for use by vdso */
 	OFFSET(VDSO_DATA_OFFSET, vdso_arch_data, data);
-	OFFSET(VDSO_RNG_DATA_OFFSET, vdso_arch_data, rng_data);
 	OFFSET(CFG_TB_TICKS_PER_SEC, vdso_arch_data, tb_ticks_per_sec);
 #ifdef CONFIG_PPC64
 	OFFSET(CFG_ICACHE_BLOCKSZ, vdso_arch_data, icache_block_size);

diff --git a/arch/powerpc/kernel/vdso.c b/arch/powerpc/kernel/vdso.c
@@ -48,12 +48,13 @@ long sys_ni_syscall(void);
  */
 static union {
 	struct vdso_arch_data	data;
-	u8			page[PAGE_SIZE];
+	u8			page[2 * PAGE_SIZE];
 } vdso_data_store __page_aligned_data;
 struct vdso_arch_data *vdso_data = &vdso_data_store.data;
 
 enum vvar_pages {
-	VVAR_DATA_PAGE_OFFSET,
+	VVAR_BASE_PAGE_OFFSET,
+	VVAR_TIME_PAGE_OFFSET,
 	VVAR_TIMENS_PAGE_OFFSET,
 	VVAR_NR_PAGES,
 };
@@ -119,7 +120,7 @@ static struct vm_special_mapping vdso64_spec __ro_after_init = {
 #ifdef CONFIG_TIME_NS
 struct vdso_data *arch_get_vdso_data(void *vvar_page)
 {
-	return ((struct vdso_arch_data *)vvar_page)->data;
+	return vvar_page;
 }
 
 /*
@@ -153,11 +154,14 @@ static vm_fault_t vvar_fault(const struct vm_special_mapping *sm,
 	unsigned long pfn;
 
 	switch (vmf->pgoff) {
-	case VVAR_DATA_PAGE_OFFSET:
+	case VVAR_BASE_PAGE_OFFSET:
+		pfn = virt_to_pfn(vdso_data);
+		break;
+	case VVAR_TIME_PAGE_OFFSET:
 		if (timens_page)
 			pfn = page_to_pfn(timens_page);
 		else
-			pfn = virt_to_pfn(vdso_data);
+			pfn = virt_to_pfn(vdso_data->data);
 		break;
 #ifdef CONFIG_TIME_NS
 	case VVAR_TIMENS_PAGE_OFFSET:
@@ -170,7 +174,7 @@ static vm_fault_t vvar_fault(const struct vm_special_mapping *sm,
 		 */
 		if (!timens_page)
 			return VM_FAULT_SIGBUS;
-		pfn = virt_to_pfn(vdso_data);
+		pfn = virt_to_pfn(vdso_data->data);
 		break;
 #endif /* CONFIG_TIME_NS */
 	default:

diff --git a/arch/powerpc/kernel/vdso/cacheflush.S b/arch/powerpc/kernel/vdso/cacheflush.S
@@ -30,7 +30,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_COHERENT_ICACHE)
 #ifdef CONFIG_PPC64
 	mflr	r12
   .cfi_register lr,r12
-	get_realdatapage	r10, r11
+	get_datapage	r10
 	mtlr	r12
   .cfi_restore	lr
 #endif

diff --git a/arch/powerpc/kernel/vdso/datapage.S b/arch/powerpc/kernel/vdso/datapage.S
@@ -28,7 +28,7 @@ V_FUNCTION_BEGIN(__kernel_get_syscall_map)
 	mflr	r12
   .cfi_register lr,r12
 	mr.	r4,r3
-	get_realdatapage	r3, r11
+	get_datapage	r3
 	mtlr	r12
 #ifdef __powerpc64__
 	addi	r3,r3,CFG_SYSCALL_MAP64
@@ -52,7 +52,7 @@ V_FUNCTION_BEGIN(__kernel_get_tbfreq)
   .cfi_startproc
 	mflr	r12
   .cfi_register lr,r12
-	get_realdatapage	r3, r11
+	get_datapage	r3
 #ifndef __powerpc64__
 	lwz	r4,(CFG_TB_TICKS_PER_SEC + 4)(r3)
 #endif

diff --git a/arch/powerpc/kernel/vdso/getrandom.S b/arch/powerpc/kernel/vdso/getrandom.S
@@ -31,8 +31,6 @@
 	PPC_STL		r2, PPC_MIN_STKFRM + STK_GOT(r1)
   .cfi_rel_offset r2, PPC_MIN_STKFRM + STK_GOT
 #endif
-	get_realdatapage	r8, r11
-	addi		r8, r8, VDSO_RNG_DATA_OFFSET
 	bl		CFUNC(DOTSYM(\funct))
 	PPC_LL		r0, PPC_MIN_STKFRM + PPC_LR_STKOFF(r1)
 #ifdef __powerpc64__

diff --git a/arch/powerpc/kernel/vdso/gettimeofday.S b/arch/powerpc/kernel/vdso/gettimeofday.S
@@ -32,11 +32,10 @@
 	PPC_STL		r2, PPC_MIN_STKFRM + STK_GOT(r1)
   .cfi_rel_offset r2, PPC_MIN_STKFRM + STK_GOT
 #endif
-	get_datapage	r5
 	.ifeq	\call_time
-	addi		r5, r5, VDSO_DATA_OFFSET
+		get_datapage	r5 VDSO_DATA_OFFSET
 	.else
-	addi		r4, r5, VDSO_DATA_OFFSET
+		get_datapage	r4 VDSO_DATA_OFFSET
 	.endif
 	bl		CFUNC(DOTSYM(\funct))
 	PPC_LL		r0, PPC_MIN_STKFRM + PPC_LR_STKOFF(r1)

diff --git a/arch/powerpc/kernel/vdso/vdso32.lds.S b/arch/powerpc/kernel/vdso/vdso32.lds.S
@@ -16,7 +16,7 @@ OUTPUT_ARCH(powerpc:common)
 
 SECTIONS
 {
-	PROVIDE(_vdso_datapage = . - 2 * PAGE_SIZE);
+	PROVIDE(_vdso_datapage = . - 3 * PAGE_SIZE);
 	. = SIZEOF_HEADERS;
 
 	.hash          	: { *(.hash) }			:text

diff --git a/arch/powerpc/kernel/vdso/vdso64.lds.S b/arch/powerpc/kernel/vdso/vdso64.lds.S
@@ -16,7 +16,7 @@ OUTPUT_ARCH(powerpc:common64)
 
 SECTIONS
 {
-	PROVIDE(_vdso_datapage = . - 2 * PAGE_SIZE);
+	PROVIDE(_vdso_datapage = . - 3 * PAGE_SIZE);
 	. = SIZEOF_HEADERS;
 
 	.hash		: { *(.hash) }			:text

diff --git a/arch/powerpc/kernel/vdso/vgetrandom.c b/arch/powerpc/kernel/vdso/vgetrandom.c
@@ -8,7 +8,7 @@
 #include <linux/types.h>
 
 ssize_t __c_kernel_getrandom(void *buffer, size_t len, unsigned int flags, void *opaque_state,
-			     size_t opaque_len, const struct vdso_rng_data *vd)
+			     size_t opaque_len)
 {
-	return __cvdso_getrandom_data(vd, buffer, len, flags, opaque_state, opaque_len);
+	return __cvdso_getrandom(buffer, len, flags, opaque_state, opaque_len);
 }