[PATCH 24/25] arm64:ilp32: add vdso-ilp32 and use for signal return

Yury Norov
2016-05-06T14:00:22Z

Hello colleagues,

After all comments, VDSO fix looks like this for me.

Note I renamed Andrew's ZERO macro to DELOUSE, as
there already is __SC_DELOUSE which does the same,
but in C, not asm.

Like Bamvor, I'm not sure how we'd apply this patch -
standalone or meld to VDSO. I think, VDSO patch is too
big and bad-structurized, and if I find how to refactor
it, I'll incorporate this fix.

Signed-off-by: Yury Norov <ynorov@caviumnetworks.com>
---
arch/arm64/kernel/asm-offsets.c | 7 +++++++
arch/arm64/kernel/vdso-ilp32/vdso-ilp32.lds.S | 2 +-
arch/arm64/kernel/vdso/gettimeofday.S | 20 +++++++++++++++++---
3 files changed, 25 insertions(+), 4 deletions(-)

diff --git a/arch/arm64/kernel/asm-offsets.c b/arch/arm64/kernel/asm-offsets.c
index e229525..fcfd087 100644
--- a/arch/arm64/kernel/asm-offsets.c
+++ b/arch/arm64/kernel/asm-offsets.c
@@ -101,6 +101,13 @@ int main(void)
DEFINE(TSPEC_TV_SEC, offsetof(struct timespec, tv_sec));
DEFINE(TSPEC_TV_NSEC, offsetof(struct timespec, tv_nsec));
BLANK();
+#ifdef CONFIG_ARM64_ILP32
+ DEFINE(COMPAT_TVAL_TV_SEC, offsetof(struct compat_timeval, tv_sec));
+ DEFINE(COMPAT_TVAL_TV_USEC, offsetof(struct compat_timeval, tv_usec));
+ DEFINE(COMPAT_TSPEC_TV_SEC, offsetof(struct compat_timespec, tv_sec));
+ DEFINE(COMPAT_TSPEC_TV_NSEC, offsetof(struct compat_timespec, tv_nsec));
+ BLANK();
+#endif
DEFINE(TZ_MINWEST, offsetof(struct timezone, tz_minuteswest));
DEFINE(TZ_DSTTIME, offsetof(struct timezone, tz_dsttime));
BLANK();
diff --git a/arch/arm64/kernel/vdso-ilp32/vdso-ilp32.lds.S b/arch/arm64/kernel/vdso-ilp32/vdso-ilp32.lds.S
index ddc63fd..d182a8d 100644
--- a/arch/arm64/kernel/vdso-ilp32/vdso-ilp32.lds.S
+++ b/arch/arm64/kernel/vdso-ilp32/vdso-ilp32.lds.S
@@ -79,7 +79,7 @@ PHDRS
*/
VERSION
{
- LINUX_2.6 {
+ LINUX_2.6.39 {
global:
__kernel_rt_sigreturn;
__kernel_gettimeofday;
diff --git a/arch/arm64/kernel/vdso/gettimeofday.S b/arch/arm64/kernel/vdso/gettimeofday.S
index efa79e8..a2d8a70 100644
--- a/arch/arm64/kernel/vdso/gettimeofday.S
+++ b/arch/arm64/kernel/vdso/gettimeofday.S
@@ -25,6 +25,16 @@
#define NSEC_PER_SEC_LO16 0xca00
#define NSEC_PER_SEC_HI16 0x3b9a

+#ifdef __LP64__
+#define PTR_REG(n) x##n
+#define OFFSET(n) n
+#define DELOUSE(n)
+#else
+#define PTR_REG(n) w##n
+#define OFFSET(n) COMPAT_##n
+#define DELOUSE(n) mov w##n, w##n
+#endif
+
vdso_data .req x6
use_syscall .req w7
seqcnt .req w8
@@ -51,6 +61,8 @@ seqcnt .req w8
/* int __kernel_gettimeofday(struct timeval *tv, struct timezone *tz); */
ENTRY(__kernel_gettimeofday)
.cfi_startproc
+ DELOUSE(0)
+ DELOUSE(1)
mov x2, x30
.cfi_register x30, x2

@@ -68,7 +80,7 @@ ENTRY(__kernel_gettimeofday)
mov x13, #1000
lsl x13, x13, x12
udiv x11, x11, x13
- stp x10, x11, [x0, #TVAL_TV_SEC]
+ stp PTR_REG(10), PTR_REG(11), [x0, #OFFSET(TVAL_TV_SEC)]
2:
/* If tz is NULL, return 0. */
cbz x1, 3f
@@ -88,6 +100,7 @@ ENDPROC(__kernel_gettimeofday)
/* int __kernel_clock_gettime(clockid_t clock_id, struct timespec *tp); */
ENTRY(__kernel_clock_gettime)
.cfi_startproc
+ DELOUSE(1)
cmp w0, #CLOCK_REALTIME
ccmp w0, #CLOCK_MONOTONIC, #0x4, ne
b.ne 2f
@@ -159,7 +172,7 @@ ENTRY(__kernel_clock_gettime)

6: /* Store to the user timespec. */
lsr x11, x11, x12
- stp x10, x11, [x1, #TSPEC_TV_SEC]
+ stp PTR_REG(10), PTR_REG(11), [x1, #OFFSET(TSPEC_TV_SEC)]
mov x0, xzr
ret
7:
@@ -174,6 +187,7 @@ ENDPROC(__kernel_clock_gettime)
/* int __kernel_clock_getres(clockid_t clock_id, struct timespec *res); */
ENTRY(__kernel_clock_getres)
.cfi_startproc
+ DELOUSE(1)
cmp w0, #CLOCK_REALTIME
ccmp w0, #CLOCK_MONOTONIC, #0x4, ne
b.ne 1f
@@ -187,7 +201,7 @@ ENTRY(__kernel_clock_getres)
ldr x2, 6f
2:
cbz w1, 3f
- stp xzr, x2, [x1]
+ stp PTR_REG(zr), PTR_REG(2), [x1]

3: /* res == NULL. */
mov w0, wzr
--
2.5.0