x86: avoid low BIOS area when allocating address space

This implements arch_remove_reservations() so allocate_resource() can
avoid any arch-specific reserved areas.  This currently just avoids the
BIOS area (the first 1MB), but could be used for E820 reserved areas if
that turns out to be necessary.

We previously avoided this area in pcibios_align_resource().  This patch
moves the test from that PCI-specific path to a generic path, so *all*
resource allocations will avoid this area.

Acked-by: H. Peter Anvin <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
Signed-off-by: Jesse Barnes <[email protected]>

diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
index 9e13763b609242e0c5429a364be461a7e8fc2594..1e994754d323f400b85c5d1d7350c6e52a702ff9 100644 (file)
--- a/arch/x86/kernel/Makefile
+++ b/arch/x86/kernel/Makefile
@@ -45,6 +45,7 @@ obj-y                 += pci-dma.o quirks.o i8237.o topology.o kdebugfs.o
 obj-y                  += alternative.o i8253.o pci-nommu.o hw_breakpoint.o
 obj-y                  += tsc.o io_delay.o rtc.o
 obj-y                  += pci-iommu_table.o
+obj-y                  += resource.o
 
 obj-$(CONFIG_X86_TRAMPOLINE)   += trampoline.o
 obj-y                          += process.o

diff --git a/arch/x86/kernel/resource.c b/arch/x86/kernel/resource.c
new file mode 100644 (file)
index 0000000..407a900
--- /dev/null
+++ b/arch/x86/kernel/resource.c
@@ -0,0 +1,11 @@
+#include <linux/ioport.h>
+#include <asm/e820.h>
+
+void arch_remove_reservations(struct resource *avail)
+{
+       /* Trim out BIOS area (low 1MB) */
+       if (avail->flags & IORESOURCE_MEM) {
+               if (avail->start < BIOS_END)
+                       avail->start = BIOS_END;
+       }
+}

diff --git a/arch/x86/pci/i386.c b/arch/x86/pci/i386.c
index 8379c2c3d076e8d2a7ee44c580af7fa06ad71d86..b1805b78842fec1efd9da3a1cebfca74c4b25371 100644 (file)
--- a/arch/x86/pci/i386.c
+++ b/arch/x86/pci/i386.c
@@ -72,9 +72,6 @@ pcibios_align_resource(void *data, const struct resource *res,
                        return start;
                if (start & 0x300)
                        start = (start + 0x3ff) & ~0x3ff;
-       } else if (res->flags & IORESOURCE_MEM) {
-               if (start < BIOS_END)
-                       start = BIOS_END;
        }
        return start;
 }