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 v3->v4:
- recombine offset into unsigned long long and split it into two longs.
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 | 24 ++++++++++++++++++++++--
1 file changed, 22 insertions(+), 2 deletions(-)
diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index 5ef517613577..eb9a31f1e092 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -3386,6 +3386,20 @@ 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)
+{
+ unsigned long long off = tlow |
+ ((unsigned long long)thigh << TARGET_LONG_BITS / 2) <<
+ TARGET_LONG_BITS / 2;
+
+ *hlow = (unsigned long)off;
+ *hhigh = (unsigned long)((off >> HOST_LONG_BITS / 2) >>
+ HOST_LONG_BITS / 2);
+}
+
static struct iovec *lock_iovec(int type, abi_ulong target_addr,
abi_ulong count, int copy)
{
@@ -10449,7 +10463,10 @@ 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 +10479,10 @@ 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
