ibft: Update iBFT handling for v1.03 of the spec.

- Use struct acpi_table_ibft instead of struct ibft_table_header
- Don't do reserve_ibft_region() on UEFI machines (section 1.4.3.1)
- If ibft_addr isn't initialized when ibft_init() is called, check for
  ACPI-based tables.
- Fix compiler error when CONFIG_ACPI is not defined.

Signed-off-by: Konrad Rzeszutek Wilk <konrad@kernel.org>
Signed-off-by: Peter Jones <pjones@redhat.com>
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>

drivers/firmware/iscsi_ibft_find.c

@@ -1,5 +1,5 @@
 /*
- *  Copyright 2007 Red Hat, Inc.
+ *  Copyright 2007-2010 Red Hat, Inc.
  *  by Peter Jones <pjones@redhat.com>
  *  Copyright 2007 IBM, Inc.
  *  by Konrad Rzeszutek <konradr@linux.vnet.ibm.com>
@@ -22,6 +22,7 @@
 #include <linux/blkdev.h>
 #include <linux/ctype.h>
 #include <linux/device.h>
+#include <linux/efi.h>
 #include <linux/err.h>
 #include <linux/init.h>
 #include <linux/limits.h>
@@ -30,13 +31,15 @@
 #include <linux/stat.h>
 #include <linux/string.h>
 #include <linux/types.h>
+#include <linux/acpi.h>
+#include <linux/iscsi_ibft.h>
 
 #include <asm/mmzone.h>
 
 /*
  * Physical location of iSCSI Boot Format Table.
  */
-struct ibft_table_header *ibft_addr;
+struct acpi_table_ibft *ibft_addr;
 EXPORT_SYMBOL_GPL(ibft_addr);
 
 #define IBFT_SIGN "iBFT"
@@ -46,6 +49,13 @@ EXPORT_SYMBOL_GPL(ibft_addr);
 #define VGA_MEM 0xA0000 /* VGA buffer */
 #define VGA_SIZE 0x20000 /* 128kB */
 
+#ifdef CONFIG_ACPI
+static int __init acpi_find_ibft(struct acpi_table_header *header)
+{
+	ibft_addr = (struct acpi_table_ibft *)header;
+	return 0;
+}
+#endif /* CONFIG_ACPI */
 
 /*
  * Routine used to find the iSCSI Boot Format Table. The logical
@@ -59,6 +69,11 @@ unsigned long __init find_ibft_region(unsigned long *sizep)
 
 	ibft_addr = NULL;
 
+	/* iBFT 1.03 section 1.4.3.1 mandates that UEFI machines will
+	 * only use ACPI for this */
+	if (efi_enabled)
+		return 0;
+
 	for (pos = IBFT_START; pos < IBFT_END; pos += 16) {
 		/* The table can't be inside the VGA BIOS reserved space,
 		 * so skip that area */
@@ -72,14 +87,24 @@ unsigned long __init find_ibft_region(unsigned long *sizep)
 			/* if the length of the table extends past 1M,
 			 * the table cannot be valid. */
 			if (pos + len <= (IBFT_END-1)) {
-				ibft_addr = (struct ibft_table_header *)virt;
+				ibft_addr = (struct acpi_table_ibft *)virt;
 				break;
 			}
 		}
 	}
+#ifdef CONFIG_ACPI
+	/*
+	 * One spec says "IBFT", the other says "iBFT". We have to check
+	 * for both.
+	 */
+	if (!ibft_addr)
+		acpi_table_parse(ACPI_SIG_IBFT, acpi_find_ibft);
+	if (!ibft_addr)
+		acpi_table_parse("iBFT", acpi_find_ibft);
+#endif /* CONFIG_ACPI */
 	if (ibft_addr) {
-		*sizep = PAGE_ALIGN(len);
-		return pos;
+		*sizep = PAGE_ALIGN(ibft_addr->header.length);
+		return (u64)isa_virt_to_bus(ibft_addr);
 	}
 
 	*sizep = 0;