I've implemented compat wrapper functions for the sys_io... set of
system calls for 32 bit emulation on s390. I think, these
wrapper functions will also be needed by architectures other than s390
(I found implementations for ppc64 and x86_64; compat_io_setup is
heavily based on the ppc64 implementation);
therefore I think they should be put into fs/compat.c.
Please verify/comment on the patch below. AFAICS they should do across
archs.
Regards,
Thomas.
diff -urN linux-2.6.0-test9/fs/compat.c linux-2.6.0-test9-compat-aio/fs/compat.c
--- linux-2.6.0-test9/fs/compat.c 2003-09-29 13:30:29.000000000 +0200
+++ linux-2.6.0-test9-compat-aio/fs/compat.c 2003-11-05 18:57:43.000000000 +0100
@@ -554,3 +554,88 @@
return compat_sys_fcntl64(fd, cmd, arg);
}
+/* posix aio functions: sys_io_... */
+extern asmlinkage long
+sys_io_setup(unsigned, aio_context_t *ctx);
+
+asmlinkage long
+sys32_io_setup(unsigned nr_events, compat_aio_context_t *ctx)
+{
+ aio_context_t kctx;
+ mm_segment_t old_fs;
+ long ret;
+
+ // ctx points to 4 byte area (u32) in userspace !
+ ret = get_user(kctx, ctx);
+ if (ret)
+ goto out;
+ old_fs = get_fs();
+ set_fs(KERNEL_DS);
+ ret = sys_io_setup(nr_events, &kctx);
+ set_fs(old_fs);
+ if (!ret)
+ ret = put_user(kctx, ctx);
+out:
+ return ret;
+}
+
+extern asmlinkage long
+sys_io_getevents(aio_context_t,long,long,struct io_event *,struct timespec *);
+
+asmlinkage long
+sys32_io_getevents(compat_aio_context_t ctx_id, long min_nr, long nr,
+ struct io_event *events,
+ struct compat_timespec *timeout)
+{
+ struct timespec ktimeout;
+ struct timespec *usr_timeout;
+ long ret;
+
+ ret = -EFAULT;
+ if ( get_compat_timespec(&ktimeout, timeout) )
+ goto out;
+ usr_timeout = compat_alloc_user_space(sizeof(*usr_timeout));
+ if ( copy_to_user(usr_timeout, &ktimeout, sizeof(ktimeout)) )
+ goto out;
+ ret = sys_io_getevents(ctx_id, min_nr, nr, events, usr_timeout);
+out:
+ return ret;
+}
+
+extern asmlinkage long
+sys_io_submit(aio_context_t, long, struct iocb __user **);
+
+static inline long
+get_64bit_user_ptr_array(long nr, u32 *ptr32, u64 *ptr64)
+{
+ u32 uptr;
+ long ret;
+
+ ret = -EFAULT;
+ int i;
+ for (i = 0; i < nr; ++i) {
+ if ( get_user(uptr, ptr32 + i) )
+ goto out;
+ if ( put_user((u64)compat_ptr(uptr), ptr64 + i) )
+ goto out;
+ }
+ ret = 0;
+out:
+ return ret;
+}
+
+asmlinkage long
+sys32_io_submit(compat_aio_context_t ctx_id, long nr, u32 *iocb)
+{
+ struct iocb **iocb64; //array of 64bit pointers in user space
+ long ret;
+
+ //alloc 64 bit pointer array in user space
+ iocb64 = compat_alloc_user_space(nr*sizeof(*iocb64));
+ ret = get_64bit_user_ptr_array(nr, (u32 *)iocb, (u64 *)iocb64);
+ if (ret)
+ goto out;
+ ret = sys_io_submit(ctx_id, nr, iocb64);
+out:
+ return ret;
+}
diff -urN linux-2.6.0-test9/include/linux/compat.h linux-2.6.0-test9-compat-aio/include/linux/compat.h
--- linux-2.6.0-test9/include/linux/compat.h 2003-10-09 19:19:51.000000000 +0200
+++ linux-2.6.0-test9-compat-aio/include/linux/compat.h 2003-11-04 15:46:54.000000000 +0100
@@ -97,5 +97,7 @@
char d_name[256];
};
+typedef unsigned int compat_aio_context_t;
+
#endif /* CONFIG_COMPAT */
#endif /* _LINUX_COMPAT_H */