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linux-user: ppc64: use the correct values for F_*LK64s 

Qemu includes the glibc headers for the host defines and target headers are
part of the qemu source themselves. The glibc has the F_GETLK64, F_SETLK64
and F_SETLKW64 defined to 12, 13 and 14 for all archs in
sysdeps/unix/sysv/linux/bits/fcntl-linux.h. The linux kernel generic
definition for F_*LK is 5, 6 & 7 and F_*LK64* is 12,13, and 14 as seen in
include/uapi/asm-generic/fcntl.h. On 64bit machine, by default the kernel
assumes all F_*LK to 64bit calls and doesnt support use of F_*LK64* as
can be seen in include/linux/fcntl.h in linux source.

On x86_64 host, the values for F_*LK64* are set to 5, 6 and 7
explicitly in /usr/include/x86_64-linux-gnu/bits/fcntl.h by the glibc.
Whereas, a PPC64 host doesn't have such a definition in
/usr/include/powerpc64le-linux-gnu/bits/fcntl.h by the glibc. So,
the sources on PPC64 host sees the default value of F_*LK64*
as 12, 13 & 14(fcntl-linux.h).

Since the 64bit kernel doesnt support 12, 13 & 14; the glibc fcntl syscall
implementation(__libc_fcntl*(), __fcntl64_nocancel) does the F_*LK64* value
convertion back to F_*LK* values on PPC64 as seen in
sysdeps/unix/sysv/linux/powerpc/powerpc64/sysdep.h with FCNTL_ADJUST_CMD()
macro. Whereas on x86_64 host the values for F_*LK64* are set to 5, 6 and 7
and no adjustments are needed.

Since qemu doesnt use the glibc fcntl, but makes the safe_syscall* on its
own, the PPC64 qemu is calling the syscall with 12, 13, and 14(without
adjustment) and they all fail. The fcntl calls to F_GETLK/F_SETLK|W all
fail by all pplications run on PPC64 host user emulation.

The fix here could be to see why on PPC64 the glibc is still keeping
F_*LK64* different from F_*LK and why adjusting them to 5, 6 and 7 before
the syscall for PPC only. See if we can make the
/usr/include/powerpc64le-linux-gnu/bits/fcntl.h to have the values
5, 6 & 7 just like x86_64 and remove the adjustment code in glibc. That
way, qemu sources see the kernel supported values in glibc headers.

OR

On PPC64 host, qemu sources see both F_*LK & F_*LK64* as same and set to
12, 13 and 14 because __USE_FILE_OFFSET64 is defined in qemu
sources(also refer sysdeps/unix/sysv/linux/bits/fcntl-linux.h).
Do the value adjustment just like it is done by glibc source by using
F_GETLK value of 5. That way, we make the syscalls with the actual
supported values in Qemu. The patch is taking this approach.

Signed-off-by: Shivaprasad G Bhat <sbhat@linux.vnet.ibm.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <153148521235.87746.14142430397318741182.stgit@lep8c.aus.stglabs.ibm.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
This commit is contained in:
Shivaprasad G Bhat 2018-07-13 07:34:46 -05:00 committed by Laurent Vivier
parent 9277d81f5c
commit 4a5457616d
1 changed files with 79 additions and 45 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

124
linux-user/syscall.c
View File

@ -6545,63 +6545,97 @@ static int do_fork(CPUArchState *env, unsigned int flags, abi_ulong newsp,
/* warning : doesn't handle linux specific flags... */
static int target_to_host_fcntl_cmd(int cmd)
{
int ret;
switch(cmd) {
case TARGET_F_DUPFD:
case TARGET_F_GETFD:
case TARGET_F_SETFD:
case TARGET_F_GETFL:
case TARGET_F_SETFL:
return cmd;
case TARGET_F_GETLK:
return F_GETLK64;
case TARGET_F_SETLK:
return F_SETLK64;
case TARGET_F_SETLKW:
return F_SETLKW64;
case TARGET_F_GETOWN:
return F_GETOWN;
case TARGET_F_SETOWN:
return F_SETOWN;
case TARGET_F_GETSIG:
return F_GETSIG;
case TARGET_F_SETSIG:
return F_SETSIG;
case TARGET_F_DUPFD:
case TARGET_F_GETFD:
case TARGET_F_SETFD:
case TARGET_F_GETFL:
case TARGET_F_SETFL:
ret = cmd;
break;
case TARGET_F_GETLK:
ret = F_GETLK64;
break;
case TARGET_F_SETLK:
ret = F_SETLK64;
break;
case TARGET_F_SETLKW:
ret = F_SETLKW64;
break;
case TARGET_F_GETOWN:
ret = F_GETOWN;
break;
case TARGET_F_SETOWN:
ret = F_SETOWN;
break;
case TARGET_F_GETSIG:
ret = F_GETSIG;
break;
case TARGET_F_SETSIG:
ret = F_SETSIG;
break;
#if TARGET_ABI_BITS == 32
case TARGET_F_GETLK64:
return F_GETLK64;
case TARGET_F_SETLK64:
return F_SETLK64;
case TARGET_F_SETLKW64:
return F_SETLKW64;
case TARGET_F_GETLK64:
ret = F_GETLK64;
break;
case TARGET_F_SETLK64:
ret = F_SETLK64;
break;
case TARGET_F_SETLKW64:
ret = F_SETLKW64;
break;
#endif
case TARGET_F_SETLEASE:
return F_SETLEASE;
case TARGET_F_GETLEASE:
return F_GETLEASE;
case TARGET_F_SETLEASE:
ret = F_SETLEASE;
break;
case TARGET_F_GETLEASE:
ret = F_GETLEASE;
break;
#ifdef F_DUPFD_CLOEXEC
case TARGET_F_DUPFD_CLOEXEC:
return F_DUPFD_CLOEXEC;
case TARGET_F_DUPFD_CLOEXEC:
ret = F_DUPFD_CLOEXEC;
break;
#endif
case TARGET_F_NOTIFY:
return F_NOTIFY;
case TARGET_F_NOTIFY:
ret = F_NOTIFY;
break;
#ifdef F_GETOWN_EX
case TARGET_F_GETOWN_EX:
return F_GETOWN_EX;
case TARGET_F_GETOWN_EX:
ret = F_GETOWN_EX;
break;
#endif
#ifdef F_SETOWN_EX
case TARGET_F_SETOWN_EX:
return F_SETOWN_EX;
case TARGET_F_SETOWN_EX:
ret = F_SETOWN_EX;
break;
#endif
#ifdef F_SETPIPE_SZ
case TARGET_F_SETPIPE_SZ:
return F_SETPIPE_SZ;
case TARGET_F_GETPIPE_SZ:
return F_GETPIPE_SZ;
case TARGET_F_SETPIPE_SZ:
ret = F_SETPIPE_SZ;
break;
case TARGET_F_GETPIPE_SZ:
ret = F_GETPIPE_SZ;
break;
#endif
default:
return -TARGET_EINVAL;
default:
ret = -TARGET_EINVAL;
break;
}
return -TARGET_EINVAL;
#if defined(__powerpc64__)
/* On PPC64, glibc headers has the F_*LK* defined to 12, 13 and 14 and
* is not supported by kernel. The glibc fcntl call actually adjusts
* them to 5, 6 and 7 before making the syscall(). Since we make the
* syscall directly, adjust to what is supported by the kernel.
*/
if (ret >= F_GETLK64 && ret <= F_SETLKW64) {
ret -= F_GETLK64 - 5;
}
#endif
return ret;
}
#define FLOCK_TRANSTBL \