[PATCH] IPMI: reserve I/O ports separately

From: Corey Minyard <minyard@acm.org>

This patch is pretty important to get in for IPMI, new systems have been
changing the way ACPI and IPMI interact, and this works around the problems
for now.  This is a temporary fix until we get proper ACPI handling in
IPMI.

Fixed releasing already-allocated regions when a later request fails, and
forward-ported it to HEAD.

Some BIOSes reserve disjoint I/O regions in their ACPI tables for the IPMI
controller.  This causes problems when trying to register the entire I/O
region.  Therefore we must register each I/O port separately.
Signed-off-by: NJordan Hargrave <Jordan_Hargrave@dell.com>
Signed-off-by: NMatt Domsch <Matt_Domsch@dell.com>
Signed-off-by: NCorey Minyard <minyard@acm.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

drivers/char/ipmi/ipmi_si_intf.c

@@ -1184,20 +1184,20 @@ static void port_outl(struct si_sm_io *io, unsigned int offset,
 static void port_cleanup(struct smi_info *info)
 {
 	unsigned int addr = info->io.addr_data;
-	int          mapsize;
+	int          idx;
 
 	if (addr) {
-		mapsize = ((info->io_size * info->io.regspacing)
-			   - (info->io.regspacing - info->io.regsize));
-
-		release_region (addr, mapsize);
+	  	for (idx = 0; idx < info->io_size; idx++) {
+			release_region(addr + idx * info->io.regspacing,
+				       info->io.regsize);
+		}
 	}
 }
 
 static int port_setup(struct smi_info *info)
 {
 	unsigned int addr = info->io.addr_data;
-	int          mapsize;
+	int          idx;
 
 	if (!addr)
 		return -ENODEV;
@@ -1225,16 +1225,22 @@ static int port_setup(struct smi_info *info)
 		return -EINVAL;
 	}
 
-	/* Calculate the total amount of memory to claim.  This is an
-	 * unusual looking calculation, but it avoids claiming any
-	 * more memory than it has to.  It will claim everything
-	 * between the first address to the end of the last full
-	 * register. */
-	mapsize = ((info->io_size * info->io.regspacing)
-		   - (info->io.regspacing - info->io.regsize));
-
-	if (request_region(addr, mapsize, DEVICE_NAME) == NULL)
-		return -EIO;
+	/* Some BIOSes reserve disjoint I/O regions in their ACPI
+	 * tables.  This causes problems when trying to register the
+	 * entire I/O region.  Therefore we must register each I/O
+	 * port separately.
+	 */
+  	for (idx = 0; idx < info->io_size; idx++) {
+		if (request_region(addr + idx * info->io.regspacing,
+				   info->io.regsize, DEVICE_NAME) == NULL) {
+			/* Undo allocations */
+			while (idx--) {
+				release_region(addr + idx * info->io.regspacing,
+					       info->io.regsize);
+			}
+			return -EIO;
+		}
+	}
 	return 0;
 }