[linuxsh-dev] pread/pwrite fix for SH-4

[SUGIOKA T. <su...@it...>]

Hi, all.

Currently, pread/pwrite system call do not work on SH-4.

This is caused by mismatch of calling convention.
(see glibc-2.2.5/sysdeps/unix/sysv/linux/pread.c)
glibc invokes pread system call with 5 long arguments,
but sys_pread takes 3 longs and 1 long long. These are
different on SH-4. (otherwise same on SH-3)

I have attached the patch which I'll commit if no one has any objections.

Index: arch/sh/kernel/entry.S
===================================================================
RCS file: /cvsroot/linuxsh/linux/arch/sh/kernel/entry.S,v
retrieving revision 1.1.1.1.2.11
diff -u -r1.1.1.1.2.11 entry.S
--- arch/sh/kernel/entry.S	1 Oct 2002 00:43:32 -0000	1.1.1.1.2.11
+++ arch/sh/kernel/entry.S	31 Oct 2002 15:14:18 -0000
@@ -1147,8 +1147,13 @@
 	.long SYMBOL_NAME(sys_rt_sigtimedwait)
 	.long SYMBOL_NAME(sys_rt_sigqueueinfo)
 	.long SYMBOL_NAME(sys_rt_sigsuspend)
+#ifdef __SH4__
+	.long SYMBOL_NAME(sh4_sys_pread)	/* 180 */
+	.long SYMBOL_NAME(sh4_sys_pwrite)
+#else
 	.long SYMBOL_NAME(sys_pread)		/* 180 */
 	.long SYMBOL_NAME(sys_pwrite)
+#endif
 	.long SYMBOL_NAME(sys_chown16)
 	.long SYMBOL_NAME(sys_getcwd)
 	.long SYMBOL_NAME(sys_capget)
Index: arch/sh/kernel/sys_sh.c
===================================================================
RCS file: /cvsroot/linuxsh/linux/arch/sh/kernel/sys_sh.c,v
retrieving revision 1.1.1.1
diff -u -r1.1.1.1 sys_sh.c
--- arch/sh/kernel/sys_sh.c	15 Oct 2001 20:44:53 -0000	1.1.1.1
+++ arch/sh/kernel/sys_sh.c	31 Oct 2002 15:14:18 -0000
@@ -84,6 +84,30 @@
 			addr = COLOUR_ALIGN(addr);
 	}
 }
+
+asmlinkage ssize_t sh4_sys_pread(unsigned int fd, char * buf,
+			     size_t count, unsigned long pos0, unsigned long pos1)
+{
+extern asmlinkage ssize_t sys_pread(unsigned int fd, char * buf,
+			     size_t count, loff_t pos);
+#ifdef __LITTLE_ENDIAN__
+	return sys_pread(fd, buf, count, (loff_t)pos0 | ((loff_t)pos1 << 32));
+#else
+	return sys_pread(fd, buf, count, (loff_t)pos1 | ((loff_t)pos0 << 32));
+#endif
+}
+
+asmlinkage ssize_t sh4_sys_pwrite(unsigned int fd, const char * buf,
+			      size_t count, unsigned long pos0, unsigned long pos1)
+{
+extern asmlinkage ssize_t sys_pwrite(unsigned int fd, char * buf,
+			     size_t count, loff_t pos);
+#ifdef __LITTLE_ENDIAN__
+	return sys_pwrite(fd, buf, count, (loff_t)pos0 | ((loff_t)pos1 << 32));
+#else
+	return sys_pwrite(fd, buf, count, (loff_t)pos1 | ((loff_t)pos0 << 32));
+#endif
+}
 #endif
 
 static inline long

----
SUGIOKA Toshinobu