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Diffstat (limited to 'sysdeps/unix/sysv/linux/s390/mmap.S')
-rw-r--r--sysdeps/unix/sysv/linux/s390/mmap.S50
1 files changed, 31 insertions, 19 deletions
diff --git a/sysdeps/unix/sysv/linux/s390/mmap.S b/sysdeps/unix/sysv/linux/s390/mmap.S
index 0ba58ccf82..f9650e9f03 100644
--- a/sysdeps/unix/sysv/linux/s390/mmap.S
+++ b/sysdeps/unix/sysv/linux/s390/mmap.S
@@ -19,33 +19,45 @@
 
 #include <sysdep.h>
 
-	.text
+#define EINVAL  22
 
+	.text
 ENTRY(__mmap)
 	/* Save registers and setup stack frame.  */
 	stm     %r6,%r15,24(%r15)
 	lr      %r1,%r15
-	l       %r0,4(0,%r15)           /* load eos */
 	ahi     %r15,-120               /* buy stack space */
-	st      %r1,0(0,%r15)           /* store back chain */
-	st      %r0,4(0,%r15)           /* store eos */
+	st      %r1,0(%r15)             /* store back chain */
 
-	/* Store parameters on stack, because old_mmap
-	 * takes only one parameter: a pointer to the parameter area
+	/* Store parameters on stack, because old_mmap/mmap2
+	 * take only one parameter: a pointer to the parameter area
 	 */
-	mvc     0x74(4,%r15),216(%r15)  /* move 'offset'  */
-	st      %r6,0x70(0,%r15)        /* store 'fd'     */
-	st      %r5,0x6C(0,%r15)        /* store 'flags'  */
-	st      %r4,0x68(0,%r15)        /* store 'prot'   */
-	st      %r3,0x64(0,%r15)        /* store 'length' */
-	st      %r2,0x60(0,%r15)        /* store 'start'  */
-
-	la      %r2,0x60(0,%r15)        /* load address of parameter list */
-	/* Do the system call trap.  */
-	svc     SYS_ify(mmap)
-
-	l       %r15,0(0,%r15)          /* load back chain */
-	lm      %r6,%r15,24(%r15)       /* load registers */
+	st      %r6,0x70(%r15)          /* Store 'fd'.      */
+	st      %r5,0x6C(%r15)          /* Store 'flags'.   */
+	st      %r4,0x68(%r15)          /* Store 'prot'.    */
+	st      %r3,0x64(%r15)          /* Store 'length'.  */
+	st      %r2,0x60(%r15)          /* Store 'start'.   */
+	l       %r1,216(%r15)           /* Load offset.     */
+
+#ifdef __ASSUME_MMAP2_SYSCALL
+	/* I don't think it is worthwhile trying to use mmap2 whenever 
+	 * it is available.  Only use it when we are sure the syscall
+	 * exists.  */
+	tml     %r1,0x0fff              /* Offset page aligned ?  */
+	lhi     %r2,-EINVAL
+	jnz     1f                      /* No -> EINVAL.  */
+	srl     %r1,12                  /* mmap2 takes the offset in pages.  */
+	st      %r1,0x74(%r15)          /* Store page offset.  */
+	la      %r2,0x60(%r15)          /* Load address of parameter list.  */
+	svc     SYS_ify(mmap2)          /* Do the system call trap.  */
+#else	
+	st      %r1,0x74(%r15)          /* Store offset unmodified.  */
+	la      %r2,0x60(%r15)          /* Load address of parameter list.  */
+	svc     SYS_ify(mmap)           /* Do the system call trap.  */
+#endif
+
+1:	l       %r15,0(%r15)            /* Load back chain.  */
+	lm      %r6,%r15,24(%r15)       /* Load registers.  */
 
 	/* check gpr 2 for error */
 	lhi     %r0,-4096