fix pread/pwrite syscall calling convention on sh

despite sh not generally using register-pair alignment for 64-bit
syscall arguments, there are arch-specific versions of the syscall
entry points for pread and pwrite which include a dummy argument for
alignment before the 64-bit offset argument.

3 files changed, 6 insertions, 2 deletions

diff --git a/src/internal/syscall.h b/src/internal/syscall.h
index ff3cf53a..6d378a81 100644
--- a/src/internal/syscall.h
+++ b/src/internal/syscall.h
@@ -12,6 +12,10 @@
 #define SYSCALL_MMAP2_UNIT 4096ULL
 #endif
 
+#ifndef __SYSCALL_LL_PRW
+#define __SYSCALL_LL_PRW(x) __SYSCALL_LL_O(x)
+#endif
+
 #ifndef __scc
 #define __scc(X) ((long) (X))
 typedef long syscall_arg_t;
diff --git a/src/unistd/pread.c b/src/unistd/pread.c
index 3d2799fd..5483eb9d 100644
--- a/src/unistd/pread.c
+++ b/src/unistd/pread.c
@@ -4,7 +4,7 @@
 
 ssize_t pread(int fd, void *buf, size_t size, off_t ofs)
 {
-	return syscall_cp(SYS_pread, fd, buf, size, __SYSCALL_LL_O(ofs));
+	return syscall_cp(SYS_pread, fd, buf, size, __SYSCALL_LL_PRW(ofs));
 }
 
 LFS64(pread);
diff --git a/src/unistd/pwrite.c b/src/unistd/pwrite.c
index bbe4c345..4bf3d7df 100644
--- a/src/unistd/pwrite.c
+++ b/src/unistd/pwrite.c
@@ -4,7 +4,7 @@
 
 ssize_t pwrite(int fd, const void *buf, size_t size, off_t ofs)
 {
-	return syscall_cp(SYS_pwrite, fd, buf, size, __SYSCALL_LL_O(ofs));
+	return syscall_cp(SYS_pwrite, fd, buf, size, __SYSCALL_LL_PRW(ofs));
 }
 
 LFS64(pwrite);