A preparation to add x86 32-bit native syscall support for the nolibc
build. On x86 32-bit, the __NR_mmap maps to sys_old_mmap:
long sys_old_mmap(struct mmap_arg_struct __user *arg);
which only receives one argument and is not suitable with the canonical
mmap() definition we use. As such, use __NR_mmap2 that maps to
sys_mmap_pgoff:
long sys_mmap_pgoff(unsigned long addr, unsigned long len,
unsigned long prot, unsigned long flags,
unsigned long fd, unsigned long pgoff);
Note: For __NR_mmap2, the offset must be shifted-right by 12-bit.
Co-authored-by: Alviro Iskandar Setiawan <alviro.iskandar@xxxxxxxxxxx>
Signed-off-by: Alviro Iskandar Setiawan <alviro.iskandar@xxxxxxxxxxx>
Signed-off-by: Ammar Faizi <ammarfaizi2@xxxxxxxxxxx>
---
src/arch/syscall-defs.h | 11 +++++++++--
1 file changed, 9 insertions(+), 2 deletions(-)
diff --git a/src/arch/syscall-defs.h b/src/arch/syscall-defs.h
index f79f56a..1e8ae1b 100644
--- a/src/arch/syscall-defs.h
+++ b/src/arch/syscall-defs.h
@@ -6,8 +6,15 @@
static inline void *__sys_mmap(void *addr, size_t length, int prot, int flags,
int fd, off_t offset)
{
- return (void *) __do_syscall6(__NR_mmap, addr, length, prot, flags, fd,
- offset);
+ int nr;
+
+#if defined(__i386__)
+ nr = __NR_mmap2;
+ offset >>= 12;
+#else
+ nr = __NR_mmap;
+#endif
+ return (void *) __do_syscall6(nr, addr, length, prot, flags, fd, offset);
}
static inline int __sys_munmap(void *addr, size_t length)
--
Ammar Faizi
