[PATCH v1 12/30] powerpc/vdso: Replace vdso_base by vdso

From: Christophe Leroy
Date: Sun Sep 27 2020 - 05:16:57 EST


All other architectures but s390 use a void pointer named 'vdso'
to reference the VDSO mapping.

In a following patch, the VDSO data page will be put in front of
text, vdso_base will then not anymore point to VDSO text.

To avoid confusion between vdso_base and VDSO text, rename vdso_base
into vdso and make it a void __user *.

Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxxxxxx>
---
arch/powerpc/include/asm/book3s/32/mmu-hash.h | 2 +-
arch/powerpc/include/asm/book3s/64/mmu.h | 2 +-
arch/powerpc/include/asm/elf.h | 2 +-
arch/powerpc/include/asm/mmu_context.h | 6 ++++--
arch/powerpc/include/asm/nohash/32/mmu-40x.h | 2 +-
arch/powerpc/include/asm/nohash/32/mmu-44x.h | 2 +-
arch/powerpc/include/asm/nohash/32/mmu-8xx.h | 2 +-
arch/powerpc/include/asm/nohash/mmu-book3e.h | 2 +-
arch/powerpc/kernel/signal_32.c | 8 ++++----
arch/powerpc/kernel/signal_64.c | 4 ++--
arch/powerpc/kernel/vdso.c | 8 ++++----
arch/powerpc/perf/callchain_32.c | 8 ++++----
arch/powerpc/perf/callchain_64.c | 4 ++--
13 files changed, 27 insertions(+), 25 deletions(-)

diff --git a/arch/powerpc/include/asm/book3s/32/mmu-hash.h b/arch/powerpc/include/asm/book3s/32/mmu-hash.h
index 2e277ca0170f..331187661236 100644
--- a/arch/powerpc/include/asm/book3s/32/mmu-hash.h
+++ b/arch/powerpc/include/asm/book3s/32/mmu-hash.h
@@ -90,7 +90,7 @@ struct hash_pte {

typedef struct {
unsigned long id;
- unsigned long vdso_base;
+ void __user *vdso;
} mm_context_t;

void update_bats(void);
diff --git a/arch/powerpc/include/asm/book3s/64/mmu.h b/arch/powerpc/include/asm/book3s/64/mmu.h
index ddc414ab3c4d..fc6cb6a712c7 100644
--- a/arch/powerpc/include/asm/book3s/64/mmu.h
+++ b/arch/powerpc/include/asm/book3s/64/mmu.h
@@ -111,7 +111,7 @@ typedef struct {

struct hash_mm_context *hash_context;

- unsigned long vdso_base;
+ void __user *vdso;
/*
* pagetable fragment support
*/
diff --git a/arch/powerpc/include/asm/elf.h b/arch/powerpc/include/asm/elf.h
index 53ed2ca40151..4ecc372c408e 100644
--- a/arch/powerpc/include/asm/elf.h
+++ b/arch/powerpc/include/asm/elf.h
@@ -169,7 +169,7 @@ do { \
NEW_AUX_ENT(AT_DCACHEBSIZE, dcache_bsize); \
NEW_AUX_ENT(AT_ICACHEBSIZE, icache_bsize); \
NEW_AUX_ENT(AT_UCACHEBSIZE, ucache_bsize); \
- VDSO_AUX_ENT(AT_SYSINFO_EHDR, current->mm->context.vdso_base); \
+ VDSO_AUX_ENT(AT_SYSINFO_EHDR, (unsigned long)current->mm->context.vdso);\
ARCH_DLINFO_CACHE_GEOMETRY; \
} while (0)

diff --git a/arch/powerpc/include/asm/mmu_context.h b/arch/powerpc/include/asm/mmu_context.h
index e02aa793420b..d54358cb5be1 100644
--- a/arch/powerpc/include/asm/mmu_context.h
+++ b/arch/powerpc/include/asm/mmu_context.h
@@ -262,8 +262,10 @@ extern void arch_exit_mmap(struct mm_struct *mm);
static inline void arch_unmap(struct mm_struct *mm,
unsigned long start, unsigned long end)
{
- if (start <= mm->context.vdso_base && mm->context.vdso_base < end)
- mm->context.vdso_base = 0;
+ unsigned long vdso_base = (unsigned long)mm->context.vdso;
+
+ if (start <= vdso_base && vdso_base < end)
+ mm->context.vdso = NULL;
}

#ifdef CONFIG_PPC_MEM_KEYS
diff --git a/arch/powerpc/include/asm/nohash/32/mmu-40x.h b/arch/powerpc/include/asm/nohash/32/mmu-40x.h
index 74f4edb5916e..8a8f13a22cf4 100644
--- a/arch/powerpc/include/asm/nohash/32/mmu-40x.h
+++ b/arch/powerpc/include/asm/nohash/32/mmu-40x.h
@@ -57,7 +57,7 @@
typedef struct {
unsigned int id;
unsigned int active;
- unsigned long vdso_base;
+ void __user *vdso;
} mm_context_t;

#endif /* !__ASSEMBLY__ */
diff --git a/arch/powerpc/include/asm/nohash/32/mmu-44x.h b/arch/powerpc/include/asm/nohash/32/mmu-44x.h
index 28aa3b339c5e..2d92a39d8f2e 100644
--- a/arch/powerpc/include/asm/nohash/32/mmu-44x.h
+++ b/arch/powerpc/include/asm/nohash/32/mmu-44x.h
@@ -108,7 +108,7 @@ extern unsigned int tlb_44x_index;
typedef struct {
unsigned int id;
unsigned int active;
- unsigned long vdso_base;
+ void __user *vdso;
} mm_context_t;

/* patch sites */
diff --git a/arch/powerpc/include/asm/nohash/32/mmu-8xx.h b/arch/powerpc/include/asm/nohash/32/mmu-8xx.h
index 1d9ac0f9c794..f0bd7f20c1e3 100644
--- a/arch/powerpc/include/asm/nohash/32/mmu-8xx.h
+++ b/arch/powerpc/include/asm/nohash/32/mmu-8xx.h
@@ -198,7 +198,7 @@ void mmu_pin_tlb(unsigned long top, bool readonly);
typedef struct {
unsigned int id;
unsigned int active;
- unsigned long vdso_base;
+ void __user *vdso;
void *pte_frag;
} mm_context_t;

diff --git a/arch/powerpc/include/asm/nohash/mmu-book3e.h b/arch/powerpc/include/asm/nohash/mmu-book3e.h
index b41004664312..e43a418d3ccd 100644
--- a/arch/powerpc/include/asm/nohash/mmu-book3e.h
+++ b/arch/powerpc/include/asm/nohash/mmu-book3e.h
@@ -238,7 +238,7 @@ extern unsigned int tlbcam_index;
typedef struct {
unsigned int id;
unsigned int active;
- unsigned long vdso_base;
+ void __user *vdso;
} mm_context_t;

/* Page size definitions, common between 32 and 64-bit
diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c
index 96950f189b5a..4dcc5e2659ce 100644
--- a/arch/powerpc/kernel/signal_32.c
+++ b/arch/powerpc/kernel/signal_32.c
@@ -785,9 +785,9 @@ int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
/* Save user registers on the stack */
frame = &rt_sf->uc.uc_mcontext;
addr = frame;
- if (vdso32_rt_sigtramp && tsk->mm->context.vdso_base) {
+ if (vdso32_rt_sigtramp && tsk->mm->context.vdso) {
sigret = 0;
- tramp = tsk->mm->context.vdso_base + vdso32_rt_sigtramp;
+ tramp = (unsigned long)tsk->mm->context.vdso + vdso32_rt_sigtramp;
} else {
sigret = __NR_rt_sigreturn;
tramp = (unsigned long) frame->tramp;
@@ -1247,9 +1247,9 @@ int handle_signal32(struct ksignal *ksig, sigset_t *oldset,
|| __put_user(ksig->sig, &sc->signal))
goto badframe;

- if (vdso32_sigtramp && tsk->mm->context.vdso_base) {
+ if (vdso32_sigtramp && tsk->mm->context.vdso) {
sigret = 0;
- tramp = tsk->mm->context.vdso_base + vdso32_sigtramp;
+ tramp = (unsigned long)tsk->mm->context.vdso + vdso32_sigtramp;
} else {
sigret = __NR_sigreturn;
tramp = (unsigned long) frame->mctx.tramp;
diff --git a/arch/powerpc/kernel/signal_64.c b/arch/powerpc/kernel/signal_64.c
index bfc939360bad..80ad09c8bc14 100644
--- a/arch/powerpc/kernel/signal_64.c
+++ b/arch/powerpc/kernel/signal_64.c
@@ -864,8 +864,8 @@ int handle_rt_signal64(struct ksignal *ksig, sigset_t *set,
tsk->thread.fp_state.fpscr = 0;

/* Set up to return from userspace. */
- if (vdso64_rt_sigtramp && tsk->mm->context.vdso_base) {
- regs->nip = tsk->mm->context.vdso_base + vdso64_rt_sigtramp;
+ if (vdso64_rt_sigtramp && tsk->mm->context.vdso) {
+ regs->nip = (unsigned long)tsk->mm->context.vdso + vdso64_rt_sigtramp;
} else {
err |= setup_trampoline(__NR_rt_sigreturn, &frame->tramp[0]);
if (err)
diff --git a/arch/powerpc/kernel/vdso.c b/arch/powerpc/kernel/vdso.c
index 971764d5b85b..87b77b793029 100644
--- a/arch/powerpc/kernel/vdso.c
+++ b/arch/powerpc/kernel/vdso.c
@@ -123,7 +123,7 @@ static int vdso_mremap(const struct vm_special_mapping *sm, struct vm_area_struc
if (new_size != text_size + PAGE_SIZE)
return -EINVAL;

- current->mm->context.vdso_base = new_vma->vm_start;
+ current->mm->context.vdso = (void __user *)new_vma->vm_start;

return 0;
}
@@ -198,7 +198,7 @@ static int __arch_setup_additional_pages(struct linux_binprm *bprm, int uses_int
* install_special_mapping or the perf counter mmap tracking code
* will fail to recognise it as a vDSO.
*/
- current->mm->context.vdso_base = vdso_base;
+ mm->context.vdso = (void __user *)vdso_base;

/*
* our vma flags don't have VM_WRITE so by default, the process isn't
@@ -224,7 +224,7 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
struct mm_struct *mm = current->mm;
int rc;

- mm->context.vdso_base = 0;
+ mm->context.vdso = NULL;

if (!vdso_ready)
return 0;
@@ -234,7 +234,7 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)

rc = __arch_setup_additional_pages(bprm, uses_interp);
if (rc)
- mm->context.vdso_base = 0;
+ mm->context.vdso = NULL;

mmap_write_unlock(mm);
return rc;
diff --git a/arch/powerpc/perf/callchain_32.c b/arch/powerpc/perf/callchain_32.c
index 64e4013d8060..b32e94047fb9 100644
--- a/arch/powerpc/perf/callchain_32.c
+++ b/arch/powerpc/perf/callchain_32.c
@@ -59,8 +59,8 @@ static int is_sigreturn_32_address(unsigned int nip, unsigned int fp)
{
if (nip == fp + offsetof(struct signal_frame_32, mctx.mc_pad))
return 1;
- if (vdso32_sigtramp && current->mm->context.vdso_base &&
- nip == current->mm->context.vdso_base + vdso32_sigtramp)
+ if (vdso32_sigtramp && current->mm->context.vdso &&
+ nip == (unsigned long)current->mm->context.vdso + vdso32_sigtramp)
return 1;
return 0;
}
@@ -70,8 +70,8 @@ static int is_rt_sigreturn_32_address(unsigned int nip, unsigned int fp)
if (nip == fp + offsetof(struct rt_signal_frame_32,
uc.uc_mcontext.mc_pad))
return 1;
- if (vdso32_rt_sigtramp && current->mm->context.vdso_base &&
- nip == current->mm->context.vdso_base + vdso32_rt_sigtramp)
+ if (vdso32_rt_sigtramp && current->mm->context.vdso &&
+ nip == (unsigned long)current->mm->context.vdso + vdso32_rt_sigtramp)
return 1;
return 0;
}
diff --git a/arch/powerpc/perf/callchain_64.c b/arch/powerpc/perf/callchain_64.c
index fed90e827f3a..c4dfe3c2702b 100644
--- a/arch/powerpc/perf/callchain_64.c
+++ b/arch/powerpc/perf/callchain_64.c
@@ -67,8 +67,8 @@ static int is_sigreturn_64_address(unsigned long nip, unsigned long fp)
{
if (nip == fp + offsetof(struct signal_frame_64, tramp))
return 1;
- if (vdso64_rt_sigtramp && current->mm->context.vdso_base &&
- nip == current->mm->context.vdso_base + vdso64_rt_sigtramp)
+ if (vdso64_rt_sigtramp && current->mm->context.vdso &&
+ nip == (unsigned long)current->mm->context.vdso + vdso64_rt_sigtramp)
return 1;
return 0;
}
--
2.25.0