preadv/pwritev accept low and high parts of file offset in two separate
parameters. When host bitness doesn't match guest bitness these parts
must be appropriately recombined.
Introduce target_to_host_low_high that does this recombination and use
it in preadv/pwritev syscalls.
This fixes glibc testsuite test misc/tst-preadvwritev64.
Signed-off-by: Max Filippov <jcmvb...@gmail.com>
---
Changes v2->v3:
- rename helper to target_to_host_low_high;
- handle cases TARGET_LONG_BITS * 2 > HOST_LONG_BITS and
TARGET_LONG_BITS < 2 * HOST_LONG_BITS correctly.
Changes v1->v2:
- fix host high computation in TARGET_LONG_BITS > HOST_LONG_BITS case
linux-user/syscall.c | 34 ++++++++++++++++++++++++++++++++--
1 file changed, 32 insertions(+), 2 deletions(-)
diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index 5ef517613577..13ad572e0d3b 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -3386,6 +3386,30 @@ static abi_long do_getsockopt(int sockfd, int level, int
optname,
return ret;
}
+static void target_to_host_low_high(abi_ulong tlow,
+ abi_ulong thigh,
+ unsigned long *hlow,
+ unsigned long *hhigh)
+{
+#if TARGET_LONG_BITS == HOST_LONG_BITS
+ *hlow = tlow;
+ *hhigh = thigh;
+#elif TARGET_LONG_BITS < HOST_LONG_BITS
+ *hlow = tlow | (unsigned long)thigh << TARGET_LONG_BITS;
+#if TARGET_LONG_BITS * 2 <= HOST_LONG_BITS
+ *hhigh = 0;
+#else
+ *hhigh = (unsigned long)thigh >> (HOST_LONG_BITS - TARGET_LONG_BITS);
+#endif
+#else
+ *hlow = (unsigned long)tlow;
+ *hhigh = (unsigned long)(tlow >> HOST_LONG_BITS);
+#if TARGET_LONG_BITS < 2 * HOST_LONG_BITS
+ *hhigh |= (unsigned long)thigh << (TARGET_LONG_BITS - HOST_LONG_BITS);
+#endif
+#endif
+}
+
static struct iovec *lock_iovec(int type, abi_ulong target_addr,
abi_ulong count, int copy)
{
@@ -10449,7 +10473,10 @@ abi_long do_syscall(void *cpu_env, int num, abi_long
arg1,
{
struct iovec *vec = lock_iovec(VERIFY_WRITE, arg2, arg3, 0);
if (vec != NULL) {
- ret = get_errno(safe_preadv(arg1, vec, arg3, arg4, arg5));
+ unsigned long low, high;
+
+ target_to_host_low_high(arg4, arg5, &low, &high);
+ ret = get_errno(safe_preadv(arg1, vec, arg3, low, high));
unlock_iovec(vec, arg2, arg3, 1);
} else {
ret = -host_to_target_errno(errno);
@@ -10462,7 +10489,10 @@ abi_long do_syscall(void *cpu_env, int num, abi_long
arg1,
{
struct iovec *vec = lock_iovec(VERIFY_READ, arg2, arg3, 1);
if (vec != NULL) {
- ret = get_errno(safe_pwritev(arg1, vec, arg3, arg4, arg5));
+ unsigned long low, high;
+
+ target_to_host_low_high(arg4, arg5, &low, &high);
+ ret = get_errno(safe_pwritev(arg1, vec, arg3, low, high));
unlock_iovec(vec, arg2, arg3, 0);
} else {
ret = -host_to_target_errno(errno);
--
2.11.0
