| Message ID | 20180406013628.25900-1-jcmvbkbc@gmail.com |
|---|---|
| State | New |
| Headers | show |
| Series | [v4] linux-user: fix preadv/pwritev offsets | expand |
Le 06/04/2018 à 03:36, Max Filippov a écrit : > 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 <jcmvbkbc@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(-) > Reviewed-by: Laurent Vivier <laurent@vivier.eu>
On 04/06/2018 11:36 AM, Max Filippov wrote: > +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; Use uint64_t instead of unsigned long long. > + > + *hlow = (unsigned long)off; > + *hhigh = (unsigned long)((off >> HOST_LONG_BITS / 2) >> > + HOST_LONG_BITS / 2); The casts here are unnecessary and are implied by the assignment. Otherwise, Reviewed-by: Richard Henderson <richard.henderson@linaro.org> r~
On Mon, Apr 9, 2018 at 5:23 PM, Richard Henderson <richard.henderson@linaro.org> wrote: > On 04/06/2018 11:36 AM, Max Filippov wrote: >> +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; > > Use uint64_t instead of unsigned long long. Ok. >> + >> + *hlow = (unsigned long)off; >> + *hhigh = (unsigned long)((off >> HOST_LONG_BITS / 2) >> >> + HOST_LONG_BITS / 2); > > The casts here are unnecessary and are implied by the assignment. Did that to avoid value truncation warning. Will drop. > Otherwise, > Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
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);
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 <jcmvbkbc@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(-)