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authorAl Viro <viro@zeniv.linux.org.uk>2013-02-24 02:17:03 -0500
committerAl Viro <viro@zeniv.linux.org.uk>2013-03-03 22:58:46 -0500
commit19f4fc3aee180000fe45952691bbe69dde1d9e95 (patch)
tree195578ae347797f6aeb66f237aeea7e0eae9847c
parent7d197ed4a68e76000070979563051e08bf6fc0aa (diff)
downloadlwn-19f4fc3aee180000fe45952691bbe69dde1d9e95.tar.gz
lwn-19f4fc3aee180000fe45952691bbe69dde1d9e95.zip
convert sendfile{,64} to COMPAT_SYSCALL_DEFINE
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
-rw-r--r--arch/mips/kernel/linux32.c20
-rw-r--r--arch/mips/kernel/scall64-n32.S2
-rw-r--r--arch/mips/kernel/scall64-o32.S2
-rw-r--r--arch/parisc/kernel/sys_parisc32.c19
-rw-r--r--arch/parisc/kernel/syscall_table.S4
-rw-r--r--arch/powerpc/include/asm/systbl.h4
-rw-r--r--arch/powerpc/kernel/sys_ppc32.c18
-rw-r--r--arch/s390/kernel/compat_linux.c42
-rw-r--r--arch/s390/kernel/compat_linux.h4
-rw-r--r--arch/s390/kernel/compat_wrapper.S14
-rw-r--r--arch/s390/kernel/syscalls.S4
-rw-r--r--arch/sparc/kernel/sys32.S1
-rw-r--r--arch/sparc/kernel/systbls_64.S2
-rw-r--r--arch/x86/ia32/sys_ia32.c20
-rw-r--r--arch/x86/include/asm/sys_ia32.h1
-rw-r--r--arch/x86/syscalls/syscall_32.tbl2
-rw-r--r--fs/compat.c22
-rw-r--r--fs/read_write.c44
-rw-r--r--fs/read_write.h2
-rw-r--r--include/linux/compat.h2
20 files changed, 54 insertions, 175 deletions
diff --git a/arch/mips/kernel/linux32.c b/arch/mips/kernel/linux32.c
index 8eeee1c860c0..b0cc2a7df59f 100644
--- a/arch/mips/kernel/linux32.c
+++ b/arch/mips/kernel/linux32.c
@@ -226,26 +226,6 @@ SYSCALL_DEFINE1(32_personality, unsigned long, personality)
return ret;
}
-SYSCALL_DEFINE4(32_sendfile, long, out_fd, long, in_fd,
- compat_off_t __user *, offset, s32, count)
-{
- mm_segment_t old_fs = get_fs();
- int ret;
- off_t of;
-
- if (offset && get_user(of, offset))
- return -EFAULT;
-
- set_fs(KERNEL_DS);
- ret = sys_sendfile(out_fd, in_fd, offset ? (off_t __user *)&of : NULL, count);
- set_fs(old_fs);
-
- if (offset && put_user(of, offset))
- return -EFAULT;
-
- return ret;
-}
-
asmlinkage ssize_t sys32_readahead(int fd, u32 pad0, u64 a2, u64 a3,
size_t count)
{
diff --git a/arch/mips/kernel/scall64-n32.S b/arch/mips/kernel/scall64-n32.S
index 693d60b0855f..9b4df498fc5b 100644
--- a/arch/mips/kernel/scall64-n32.S
+++ b/arch/mips/kernel/scall64-n32.S
@@ -143,7 +143,7 @@ EXPORT(sysn32_call_table)
PTR compat_sys_setitimer
PTR sys_alarm
PTR sys_getpid
- PTR sys_32_sendfile
+ PTR compat_sys_sendfile
PTR sys_socket /* 6040 */
PTR sys_connect
PTR sys_accept
diff --git a/arch/mips/kernel/scall64-o32.S b/arch/mips/kernel/scall64-o32.S
index af8887f779f1..c1a70e805751 100644
--- a/arch/mips/kernel/scall64-o32.S
+++ b/arch/mips/kernel/scall64-o32.S
@@ -399,7 +399,7 @@ sys_call_table:
PTR sys_capget
PTR sys_capset /* 4205 */
PTR compat_sys_sigaltstack
- PTR sys_32_sendfile
+ PTR compat_sys_sendfile
PTR sys_ni_syscall
PTR sys_ni_syscall
PTR sys_mips_mmap2 /* 4210 */
diff --git a/arch/parisc/kernel/sys_parisc32.c b/arch/parisc/kernel/sys_parisc32.c
index 051c8b90231f..035ab3f94814 100644
--- a/arch/parisc/kernel/sys_parisc32.c
+++ b/arch/parisc/kernel/sys_parisc32.c
@@ -60,25 +60,6 @@ asmlinkage long sys32_unimplemented(int r26, int r25, int r24, int r23,
return -ENOSYS;
}
-/* Note: it is necessary to treat out_fd and in_fd as unsigned ints, with the
- * corresponding cast to a signed int to insure that the proper conversion
- * (sign extension) between the register representation of a signed int (msr in
- * 32-bit mode) and the register representation of a signed int (msr in 64-bit
- * mode) is performed.
- */
-asmlinkage long sys32_sendfile(u32 out_fd, u32 in_fd,
- compat_off_t __user *offset, compat_size_t count)
-{
- return compat_sys_sendfile((int)out_fd, (int)in_fd, offset, count);
-}
-
-asmlinkage long sys32_sendfile64(u32 out_fd, u32 in_fd,
- compat_loff_t __user *offset, compat_size_t count)
-{
- return sys_sendfile64((int)out_fd, (int)in_fd,
- (loff_t __user *)offset, count);
-}
-
asmlinkage long sys32_semctl(int semid, int semnum, int cmd, union semun arg)
{
union semun u;
diff --git a/arch/parisc/kernel/syscall_table.S b/arch/parisc/kernel/syscall_table.S
index f57dc137b8dd..f232672a9e20 100644
--- a/arch/parisc/kernel/syscall_table.S
+++ b/arch/parisc/kernel/syscall_table.S
@@ -198,7 +198,7 @@
ENTRY_SAME(madvise)
ENTRY_SAME(clone_wrapper) /* 120 */
ENTRY_SAME(setdomainname)
- ENTRY_DIFF(sendfile)
+ ENTRY_COMP(sendfile)
/* struct sockaddr... */
ENTRY_SAME(recvfrom)
/* struct timex contains longs */
@@ -304,7 +304,7 @@
ENTRY_SAME(gettid)
ENTRY_OURS(readahead)
ENTRY_SAME(tkill)
- ENTRY_DIFF(sendfile64)
+ ENTRY_COMP(sendfile64)
ENTRY_COMP(futex) /* 210 */
ENTRY_COMP(sched_setaffinity)
ENTRY_COMP(sched_getaffinity)
diff --git a/arch/powerpc/include/asm/systbl.h b/arch/powerpc/include/asm/systbl.h
index 535b6d8a41cc..634db7d2dc92 100644
--- a/arch/powerpc/include/asm/systbl.h
+++ b/arch/powerpc/include/asm/systbl.h
@@ -190,7 +190,7 @@ SYSCALL_SPU(getcwd)
SYSCALL_SPU(capget)
SYSCALL_SPU(capset)
COMPAT_SYS(sigaltstack)
-SYSX_SPU(sys_sendfile,compat_sys_sendfile_wrapper,sys_sendfile)
+COMPAT_SYS_SPU(sendfile)
SYSCALL(ni_syscall)
SYSCALL(ni_syscall)
PPC_SYS(vfork)
@@ -230,7 +230,7 @@ COMPAT_SYS_SPU(sched_setaffinity)
COMPAT_SYS_SPU(sched_getaffinity)
SYSCALL(ni_syscall)
SYSCALL(ni_syscall)
-SYSX(sys_ni_syscall,compat_sys_sendfile64_wrapper,sys_sendfile64)
+SYS32ONLY(sendfile64)
COMPAT_SYS_SPU(io_setup)
SYSCALL_SPU(io_destroy)
COMPAT_SYS_SPU(io_getevents)
diff --git a/arch/powerpc/kernel/sys_ppc32.c b/arch/powerpc/kernel/sys_ppc32.c
index d0bafc0cdf06..6e7c2509bd2d 100644
--- a/arch/powerpc/kernel/sys_ppc32.c
+++ b/arch/powerpc/kernel/sys_ppc32.c
@@ -128,24 +128,6 @@ long compat_sys_ipc(u32 call, u32 first, u32 second, u32 third, compat_uptr_t pt
}
#endif
-/* Note: it is necessary to treat out_fd and in_fd as unsigned ints,
- * with the corresponding cast to a signed int to insure that the
- * proper conversion (sign extension) between the register representation of a signed int (msr in 32-bit mode)
- * and the register representation of a signed int (msr in 64-bit mode) is performed.
- */
-asmlinkage long compat_sys_sendfile_wrapper(u32 out_fd, u32 in_fd,
- compat_off_t __user *offset, u32 count)
-{
- return compat_sys_sendfile((int)out_fd, (int)in_fd, offset, count);
-}
-
-asmlinkage long compat_sys_sendfile64_wrapper(u32 out_fd, u32 in_fd,
- compat_loff_t __user *offset, u32 count)
-{
- return sys_sendfile((int)out_fd, (int)in_fd,
- (off_t __user *)offset, count);
-}
-
unsigned long compat_sys_mmap2(unsigned long addr, size_t len,
unsigned long prot, unsigned long flags,
unsigned long fd, unsigned long pgoff)
diff --git a/arch/s390/kernel/compat_linux.c b/arch/s390/kernel/compat_linux.c
index 19f26de27fae..fbd29c70a297 100644
--- a/arch/s390/kernel/compat_linux.c
+++ b/arch/s390/kernel/compat_linux.c
@@ -373,48 +373,6 @@ asmlinkage compat_ssize_t sys32_readahead(int fd, u32 offhi, u32 offlo, s32 coun
return sys_readahead(fd, ((loff_t)AA(offhi) << 32) | AA(offlo), count);
}
-asmlinkage long sys32_sendfile(int out_fd, int in_fd, compat_off_t __user *offset, size_t count)
-{
- mm_segment_t old_fs = get_fs();
- int ret;
- off_t of;
-
- if (offset && get_user(of, offset))
- return -EFAULT;
-
- set_fs(KERNEL_DS);
- ret = sys_sendfile(out_fd, in_fd,
- offset ? (off_t __force __user *) &of : NULL, count);
- set_fs(old_fs);
-
- if (offset && put_user(of, offset))
- return -EFAULT;
-
- return ret;
-}
-
-asmlinkage long sys32_sendfile64(int out_fd, int in_fd,
- compat_loff_t __user *offset, s32 count)
-{
- mm_segment_t old_fs = get_fs();
- int ret;
- loff_t lof;
-
- if (offset && get_user(lof, offset))
- return -EFAULT;
-
- set_fs(KERNEL_DS);
- ret = sys_sendfile64(out_fd, in_fd,
- offset ? (loff_t __force __user *) &lof : NULL,
- count);
- set_fs(old_fs);
-
- if (offset && put_user(lof, offset))
- return -EFAULT;
-
- return ret;
-}
-
struct stat64_emu31 {
unsigned long long st_dev;
unsigned int __pad1;
diff --git a/arch/s390/kernel/compat_linux.h b/arch/s390/kernel/compat_linux.h
index 00d92a5a6f6c..bce0b7aec8f9 100644
--- a/arch/s390/kernel/compat_linux.h
+++ b/arch/s390/kernel/compat_linux.h
@@ -106,10 +106,6 @@ long sys32_pread64(unsigned int fd, char __user *ubuf, size_t count,
long sys32_pwrite64(unsigned int fd, const char __user *ubuf,
size_t count, u32 poshi, u32 poslo);
compat_ssize_t sys32_readahead(int fd, u32 offhi, u32 offlo, s32 count);
-long sys32_sendfile(int out_fd, int in_fd, compat_off_t __user *offset,
- size_t count);
-long sys32_sendfile64(int out_fd, int in_fd, compat_loff_t __user *offset,
- s32 count);
long sys32_stat64(const char __user * filename, struct stat64_emu31 __user * statbuf);
long sys32_lstat64(const char __user * filename,
struct stat64_emu31 __user * statbuf);
diff --git a/arch/s390/kernel/compat_wrapper.S b/arch/s390/kernel/compat_wrapper.S
index 626cc6f0f446..a1dda9c67efe 100644
--- a/arch/s390/kernel/compat_wrapper.S
+++ b/arch/s390/kernel/compat_wrapper.S
@@ -666,13 +666,6 @@ ENTRY(sys32_capset_wrapper)
llgtr %r3,%r3 # const cap_user_data_t
jg sys_capset # branch to system call
-ENTRY(sys32_sendfile_wrapper)
- lgfr %r2,%r2 # int
- lgfr %r3,%r3 # int
- llgtr %r4,%r4 # __kernel_off_emu31_t *
- llgfr %r5,%r5 # size_t
- jg sys32_sendfile # branch to system call
-
#sys32_vfork_wrapper # done in vfork_glue
ENTRY(sys32_truncate64_wrapper)
@@ -1348,13 +1341,6 @@ ENTRY(sys32_readahead_wrapper)
lgfr %r5,%r5 # s32
jg sys32_readahead # branch to system call
-ENTRY(sys32_sendfile64_wrapper)
- lgfr %r2,%r2 # int
- lgfr %r3,%r3 # int
- llgtr %r4,%r4 # compat_loff_t *
- lgfr %r5,%r5 # s32
- jg sys32_sendfile64 # branch to system call
-
ENTRY(sys_tkill_wrapper)
lgfr %r2,%r2 # pid_t
lgfr %r3,%r3 # int
diff --git a/arch/s390/kernel/syscalls.S b/arch/s390/kernel/syscalls.S
index 2695bb89699e..5f3f7fbc5465 100644
--- a/arch/s390/kernel/syscalls.S
+++ b/arch/s390/kernel/syscalls.S
@@ -195,7 +195,7 @@ SYSCALL(sys_getcwd,sys_getcwd,sys32_getcwd_wrapper)
SYSCALL(sys_capget,sys_capget,sys32_capget_wrapper)
SYSCALL(sys_capset,sys_capset,sys32_capset_wrapper) /* 185 */
SYSCALL(sys_sigaltstack,sys_sigaltstack,compat_sys_sigaltstack)
-SYSCALL(sys_sendfile,sys_sendfile64,sys32_sendfile_wrapper)
+SYSCALL(sys_sendfile,sys_sendfile64,compat_sys_sendfile)
NI_SYSCALL /* streams1 */
NI_SYSCALL /* streams2 */
SYSCALL(sys_vfork,sys_vfork,sys_vfork) /* 190 */
@@ -231,7 +231,7 @@ SYSCALL(sys_madvise,sys_madvise,sys32_madvise_wrapper)
SYSCALL(sys_getdents64,sys_getdents64,sys32_getdents64_wrapper) /* 220 */
SYSCALL(sys_fcntl64,sys_ni_syscall,compat_sys_fcntl64_wrapper)
SYSCALL(sys_readahead,sys_readahead,sys32_readahead_wrapper)
-SYSCALL(sys_sendfile64,sys_ni_syscall,sys32_sendfile64_wrapper)
+SYSCALL(sys_sendfile64,sys_ni_syscall,compat_sys_sendfile64)
SYSCALL(sys_setxattr,sys_setxattr,sys32_setxattr_wrapper)
SYSCALL(sys_lsetxattr,sys_lsetxattr,sys32_lsetxattr_wrapper) /* 225 */
SYSCALL(sys_fsetxattr,sys_fsetxattr,sys32_fsetxattr_wrapper)
diff --git a/arch/sparc/kernel/sys32.S b/arch/sparc/kernel/sys32.S
index 240a3cecc11e..6c65d69c6635 100644
--- a/arch/sparc/kernel/sys32.S
+++ b/arch/sparc/kernel/sys32.S
@@ -46,7 +46,6 @@ SIGN1(sys32_io_submit, compat_sys_io_submit, %o1)
SIGN1(sys32_mq_open, compat_sys_mq_open, %o1)
SIGN1(sys32_select, compat_sys_select, %o0)
SIGN3(sys32_futex, compat_sys_futex, %o1, %o2, %o5)
-SIGN2(sys32_sendfile, compat_sys_sendfile, %o0, %o1)
SIGN1(sys32_recvfrom, compat_sys_recvfrom, %o0)
SIGN1(sys32_recvmsg, compat_sys_recvmsg, %o0)
SIGN1(sys32_sendmsg, compat_sys_sendmsg, %o0)
diff --git a/arch/sparc/kernel/systbls_64.S b/arch/sparc/kernel/systbls_64.S
index 088134834dab..a1444d0d08ee 100644
--- a/arch/sparc/kernel/systbls_64.S
+++ b/arch/sparc/kernel/systbls_64.S
@@ -25,7 +25,7 @@ sys_call_table32:
/*20*/ .word sys_getpid, sys_capget, sys_capset, sys_setuid16, sys_getuid16
/*25*/ .word sys32_vmsplice, compat_sys_ptrace, sys_alarm, compat_sys_sigaltstack, sys_pause
/*30*/ .word compat_sys_utime, sys_lchown, sys_fchown, sys_access, sys_nice
- .word sys_chown, sys_sync, sys_kill, compat_sys_newstat, sys32_sendfile
+ .word sys_chown, sys_sync, sys_kill, compat_sys_newstat, compat_sys_sendfile
/*40*/ .word compat_sys_newlstat, sys_dup, sys_sparc_pipe, compat_sys_times, sys_getuid
.word sys_umount, sys_setgid16, sys_getgid16, sys_signal, sys_geteuid16
/*50*/ .word sys_getegid16, sys_acct, sys_nis_syscall, sys_getgid, compat_sys_ioctl
diff --git a/arch/x86/ia32/sys_ia32.c b/arch/x86/ia32/sys_ia32.c
index ad7a20cbc699..ad6ca0472722 100644
--- a/arch/x86/ia32/sys_ia32.c
+++ b/arch/x86/ia32/sys_ia32.c
@@ -194,26 +194,6 @@ asmlinkage long sys32_pwrite(unsigned int fd, const char __user *ubuf,
}
-asmlinkage long sys32_sendfile(int out_fd, int in_fd,
- compat_off_t __user *offset, s32 count)
-{
- mm_segment_t old_fs = get_fs();
- int ret;
- off_t of;
-
- if (offset && get_user(of, offset))
- return -EFAULT;
-
- set_fs(KERNEL_DS);
- ret = sys_sendfile(out_fd, in_fd, offset ? (off_t __user *)&of : NULL,
- count);
- set_fs(old_fs);
-
- if (offset && put_user(of, offset))
- return -EFAULT;
- return ret;
-}
-
/*
* Some system calls that need sign extended arguments. This could be
* done by a generic wrapper.
diff --git a/arch/x86/include/asm/sys_ia32.h b/arch/x86/include/asm/sys_ia32.h
index 8459efc39686..6d944e4bb524 100644
--- a/arch/x86/include/asm/sys_ia32.h
+++ b/arch/x86/include/asm/sys_ia32.h
@@ -41,7 +41,6 @@ asmlinkage long sys32_pread(unsigned int, char __user *, u32, u32, u32);
asmlinkage long sys32_pwrite(unsigned int, const char __user *, u32, u32, u32);
asmlinkage long sys32_personality(unsigned long);
-asmlinkage long sys32_sendfile(int, int, compat_off_t __user *, s32);
long sys32_kill(int, int);
long sys32_fadvise64_64(int, __u32, __u32, __u32, __u32, int);
diff --git a/arch/x86/syscalls/syscall_32.tbl b/arch/x86/syscalls/syscall_32.tbl
index e6d55f0064df..6a00b1257d68 100644
--- a/arch/x86/syscalls/syscall_32.tbl
+++ b/arch/x86/syscalls/syscall_32.tbl
@@ -193,7 +193,7 @@
184 i386 capget sys_capget
185 i386 capset sys_capset
186 i386 sigaltstack sys_sigaltstack compat_sys_sigaltstack
-187 i386 sendfile sys_sendfile sys32_sendfile
+187 i386 sendfile sys_sendfile compat_sys_sendfile
188 i386 getpmsg
189 i386 putpmsg
190 i386 vfork sys_vfork stub32_vfork
diff --git a/fs/compat.c b/fs/compat.c
index cc09312f9aed..2ae2a98891cd 100644
--- a/fs/compat.c
+++ b/fs/compat.c
@@ -1718,25 +1718,3 @@ COMPAT_SYSCALL_DEFINE3(open_by_handle_at, int, mountdirfd,
return do_handle_open(mountdirfd, handle, flags);
}
#endif
-
-#ifdef __ARCH_WANT_COMPAT_SYS_SENDFILE
-asmlinkage long compat_sys_sendfile(int out_fd, int in_fd,
- compat_off_t __user *offset, compat_size_t count)
-{
- loff_t pos;
- off_t off;
- ssize_t ret;
-
- if (offset) {
- if (unlikely(get_user(off, offset)))
- return -EFAULT;
- pos = off;
- ret = do_sendfile(out_fd, in_fd, &pos, count, MAX_NON_LFS);
- if (unlikely(put_user(pos, offset)))
- return -EFAULT;
- return ret;
- }
-
- return do_sendfile(out_fd, in_fd, NULL, count, 0);
-}
-#endif /* __ARCH_WANT_COMPAT_SYS_SENDFILE */
diff --git a/fs/read_write.c b/fs/read_write.c
index dcfd58d95f44..f738e4dccfab 100644
--- a/fs/read_write.c
+++ b/fs/read_write.c
@@ -853,8 +853,8 @@ SYSCALL_DEFINE5(pwritev, unsigned long, fd, const struct iovec __user *, vec,
return ret;
}
-ssize_t do_sendfile(int out_fd, int in_fd, loff_t *ppos, size_t count,
- loff_t max)
+static ssize_t do_sendfile(int out_fd, int in_fd, loff_t *ppos,
+ size_t count, loff_t max)
{
struct fd in, out;
struct inode *in_inode, *out_inode;
@@ -978,3 +978,43 @@ SYSCALL_DEFINE4(sendfile64, int, out_fd, int, in_fd, loff_t __user *, offset, si
return do_sendfile(out_fd, in_fd, NULL, count, 0);
}
+
+#ifdef CONFIG_COMPAT
+COMPAT_SYSCALL_DEFINE4(sendfile, int, out_fd, int, in_fd,
+ compat_off_t __user *, offset, compat_size_t, count)
+{
+ loff_t pos;
+ off_t off;
+ ssize_t ret;
+
+ if (offset) {
+ if (unlikely(get_user(off, offset)))
+ return -EFAULT;
+ pos = off;
+ ret = do_sendfile(out_fd, in_fd, &pos, count, MAX_NON_LFS);
+ if (unlikely(put_user(pos, offset)))
+ return -EFAULT;
+ return ret;
+ }
+
+ return do_sendfile(out_fd, in_fd, NULL, count, 0);
+}
+
+COMPAT_SYSCALL_DEFINE4(sendfile64, int, out_fd, int, in_fd,
+ compat_loff_t __user *, offset, compat_size_t, count)
+{
+ loff_t pos;
+ ssize_t ret;
+
+ if (offset) {
+ if (unlikely(copy_from_user(&pos, offset, sizeof(loff_t))))
+ return -EFAULT;
+ ret = do_sendfile(out_fd, in_fd, &pos, count, 0);
+ if (unlikely(put_user(pos, offset)))
+ return -EFAULT;
+ return ret;
+ }
+
+ return do_sendfile(out_fd, in_fd, NULL, count, 0);
+}
+#endif
diff --git a/fs/read_write.h b/fs/read_write.h
index d3e00ef67420..d07b954c6e0c 100644
--- a/fs/read_write.h
+++ b/fs/read_write.h
@@ -12,5 +12,3 @@ ssize_t do_sync_readv_writev(struct file *filp, const struct iovec *iov,
unsigned long nr_segs, size_t len, loff_t *ppos, iov_fn_t fn);
ssize_t do_loop_readv_writev(struct file *filp, struct iovec *iov,
unsigned long nr_segs, loff_t *ppos, io_fn_t fn);
-ssize_t do_sendfile(int out_fd, int in_fd, loff_t *ppos, size_t count,
- loff_t max);
diff --git a/include/linux/compat.h b/include/linux/compat.h
index 110132527e4c..ad299afcd488 100644
--- a/include/linux/compat.h
+++ b/include/linux/compat.h
@@ -670,6 +670,8 @@ asmlinkage ssize_t compat_sys_process_vm_writev(compat_pid_t pid,
asmlinkage long compat_sys_sendfile(int out_fd, int in_fd,
compat_off_t __user *offset, compat_size_t count);
+asmlinkage long compat_sys_sendfile64(int out_fd, int in_fd,
+ compat_loff_t __user *offset, compat_size_t count);
asmlinkage long compat_sys_sigaltstack(const compat_stack_t __user *uss_ptr,
compat_stack_t __user *uoss_ptr);