Tweak the bootmap setup code to be more conservative, and not assume

that we can throw the bootmap right after _end.  This allows strange
and useful things like embedding root ramdisks into the kernel using
linker scripts and symbol tweaks.  This patch also fixes the generic
initrd handling code that was commented out as broken.  Patch from
Justin.

1 files changed, 26 insertions, 22 deletions

diff --git a/arch/mips/kernel/setup.c b/arch/mips/kernel/setup.c
index 04f2ee113..4f12b01f5 100644
--- a/arch/mips/kernel/setup.c
+++ b/arch/mips/kernel/setup.c
@@ -461,11 +461,12 @@ void __init setup_arch(char **cmdline_p)
 	void momenco_ocelot_setup(void);
 	void nino_setup(void);
 
-#ifdef CONFIG_BLK_DEV_INITRD
+#ifdef CONFIG_NINO
 	extern void * __rd_start, * __rd_end;
 #endif
 	unsigned long bootmap_size;
-	unsigned long start_pfn, max_pfn;
+	unsigned long start_pfn, max_pfn, first_usable_pfn;
+
 	int i;
 
 	/* Save defaults for configuration-dependent routines.  */
@@ -582,6 +583,7 @@ void __init setup_arch(char **cmdline_p)
 
 	/* Find the highest page frame number we have available.  */
 	max_pfn = 0;
+	first_usable_pfn = -1UL;
 	for (i = 0; i < boot_mem_map.nr_map; i++) {
 		unsigned long start, end;
 
@@ -596,10 +598,17 @@ void __init setup_arch(char **cmdline_p)
 			continue;
 		if (end > max_pfn)
 			max_pfn = end;
+		if (start < first_usable_pfn) {
+			if (start > start_pfn) {
+				first_usable_pfn = start;
+			} else if (end > start_pfn) {
+				first_usable_pfn = start_pfn;
+			}
+		}
 	}
-
+	
 	/* Initialize the boot-time allocator.  */
-	bootmap_size = init_bootmem(start_pfn, max_pfn);
+	bootmap_size = init_bootmem(first_usable_pfn, max_pfn);
 
 	/*
 	 * Register fully available low RAM pages with the bootmem allocator.
@@ -643,7 +652,7 @@ void __init setup_arch(char **cmdline_p)
 	}
 
 	/* Reserve the bootmap memory.  */
-	reserve_bootmem(PFN_PHYS(start_pfn), bootmap_size);
+	reserve_bootmem(PFN_PHYS(first_usable_pfn), bootmap_size);
 
 #ifdef CONFIG_NINO
 	ROOT_DEV = MKDEV(RAMDISK_MAJOR, 0);
@@ -652,27 +661,22 @@ void __init setup_arch(char **cmdline_p)
 	initrd_below_start_ok = 1;
 #endif
 
-#if 0
 #ifdef CONFIG_BLK_DEV_INITRD
-#error "Fixme, I'm broken."
-	tmp = (((unsigned long)&_end + PAGE_SIZE-1) & PAGE_MASK) - 8;
-	if (tmp < (unsigned long)&_end)
-		tmp += PAGE_SIZE;
-	initrd_header = (unsigned long *)tmp;
-	if (initrd_header[0] == 0x494E5244) {
-		initrd_start = (unsigned long)&initrd_header[2];
-		initrd_end = initrd_start + initrd_header[1];
-		initrd_below_start_ok = 1;
-		if (initrd_end > memory_end) {
+	/* Board specific code should have set up initrd_start and initrd_end */
+	if (initrd_start) {
+		unsigned long initrd_size = ((unsigned char *)initrd_end) - ((unsigned char *)initrd_start); 
+		printk("Initial ramdisk at: 0x%p (%lu bytes)\n",
+		       (void *)initrd_start, 
+		       initrd_size);
+		if ((void *)initrd_end > phys_to_virt(PFN_PHYS(max_low_pfn))) {
 			printk("initrd extends beyond end of memory "
-			       "(0x%08lx > 0x%08lx)\ndisabling initrd\n",
-			       initrd_end,memory_end);
-			initrd_start = 0;
-		} else
-			*memory_start_p = initrd_end;
+			       "(0x%lx > 0x%p)\ndisabling initrd\n",
+			       initrd_end,
+			       phys_to_virt(PFN_PHYS(max_low_pfn)));
+			initrd_start = initrd_end = 0;
+		} 
 	}
 #endif /* CONFIG_BLK_DEV_INITRD  */
-#endif /* 0  */
 
 	paging_init();