Variable PTE_FILE_MAX_BITS

[Pete Zaitcev]

Andrew,

would you be so kind to take this and forward to Linus?
I think this segment of the code is your brainchild.

On sparc, the PTE_FILE_MAX_BITS is variable (Worse, actually...
we change all occurences in kernel text segment to correct value
at boot time.) This should not harm other arches, because
gcc is capable to optimize constant conditions.

-- Pete

--- linux-2.5.66-bk11/mm/fremap.c	2003-04-05 13:26:24.000000000 -0800
+++ linux-2.5.66-bk11-sparc/mm/fremap.c	2003-04-05 13:28:22.000000000 -0800
@@ -136,10 +136,10 @@
 		return err;
 
 	/* Can we represent this offset inside this architecture's pte's? */
-#if PTE_FILE_MAX_BITS < BITS_PER_LONG
-	if (pgoff + (size >> PAGE_SHIFT) >= (1UL << PTE_FILE_MAX_BITS))
-		return err;
-#endif
+	/* This needs to be evaluated at runtime on some platforms */
+	if (PTE_FILE_MAX_BITS < BITS_PER_LONG)
+		if (pgoff + (size >> PAGE_SHIFT) >= (1UL << PTE_FILE_MAX_BITS))
+			return err;
 
 	down_read(&mm->mmap_sem);