Rename e820_mapped to e820_any_mapped since it tests if any part
of the range is mapped according to the type. Later steps will introduce
e820_all_mapped which will check if the entire range is mapped with the type.
Both have their merit.
Signed-off-by: Arjan van de Ven <[email protected]>
---
arch/x86_64/kernel/aperture.c | 2 +-
arch/x86_64/kernel/e820.c | 2 +-
arch/x86_64/mm/init.c | 2 +-
include/asm-x86_64/e820.h | 2 +-
4 files changed, 4 insertions(+), 4 deletions(-)
Index: linux-2.6.16-mmconfig/arch/x86_64/kernel/aperture.c
===================================================================
--- linux-2.6.16-mmconfig.orig/arch/x86_64/kernel/aperture.c
+++ linux-2.6.16-mmconfig/arch/x86_64/kernel/aperture.c
@@ -80,7 +80,7 @@ static int __init aperture_valid(char *n
printk("Aperture from %s beyond 4GB. Ignoring.\n",name);
return 0;
}
- if (e820_mapped(aper_base, aper_base + aper_size, E820_RAM)) {
+ if (e820_any_mapped(aper_base, aper_base + aper_size, E820_RAM)) {
printk("Aperture from %s pointing to e820 RAM. Ignoring.\n",name);
return 0;
}
Index: linux-2.6.16-mmconfig/arch/x86_64/kernel/e820.c
===================================================================
--- linux-2.6.16-mmconfig.orig/arch/x86_64/kernel/e820.c
+++ linux-2.6.16-mmconfig/arch/x86_64/kernel/e820.c
@@ -80,7 +80,7 @@ static inline int bad_addr(unsigned long
return 0;
}
-int __init e820_mapped(unsigned long start, unsigned long end, unsigned type)
+int __init e820_any_mapped(unsigned long start, unsigned long end, unsigned type)
{
int i;
for (i = 0; i < e820.nr_map; i++) {
Index: linux-2.6.16-mmconfig/arch/x86_64/mm/init.c
===================================================================
--- linux-2.6.16-mmconfig.orig/arch/x86_64/mm/init.c
+++ linux-2.6.16-mmconfig/arch/x86_64/mm/init.c
@@ -277,7 +277,7 @@ static void __meminit phys_pud_init(pud_
if (paddr >= end)
break;
- if (!after_bootmem && !e820_mapped(paddr, paddr+PUD_SIZE, 0)) {
+ if (!after_bootmem && !e820_any_mapped(paddr, paddr+PUD_SIZE, 0)) {
set_pud(pud, __pud(0));
continue;
}
Index: linux-2.6.16-mmconfig/include/asm-x86_64/e820.h
===================================================================
--- linux-2.6.16-mmconfig.orig/include/asm-x86_64/e820.h
+++ linux-2.6.16-mmconfig/include/asm-x86_64/e820.h
@@ -47,7 +47,7 @@ extern void contig_e820_setup(void);
extern unsigned long e820_end_of_ram(void);
extern void e820_reserve_resources(void);
extern void e820_print_map(char *who);
-extern int e820_mapped(unsigned long start, unsigned long end, unsigned type);
+extern int e820_any_mapped(unsigned long start, unsigned long end, unsigned type);
extern void e820_bootmem_free(pg_data_t *pgdat, unsigned long start,unsigned long end);
extern void e820_setup_gap(void);
Introduce a e820_all_mapped() function which checks if the entire
range <start,end> is mapped with type. This is done by moving the local
start variable to the end of each known-good region; if at the end
of the function the start address is still before end, there must be
a part that's not of the correct type; otherwise it's a good region.
Signed-off-by: Arjan van de Ven <[email protected]>
---
arch/x86_64/kernel/e820.c | 32 ++++++++++++++++++++++++++++++++
include/asm-x86_64/e820.h | 1 +
2 files changed, 33 insertions(+)
Index: linux-2.6.16-mmconfig/arch/x86_64/kernel/e820.c
===================================================================
--- linux-2.6.16-mmconfig.orig/arch/x86_64/kernel/e820.c
+++ linux-2.6.16-mmconfig/arch/x86_64/kernel/e820.c
@@ -80,6 +80,9 @@ static inline int bad_addr(unsigned long
return 0;
}
+/*
+ * This function checks if any part of the range <start,end> is mapped with type.
+ */
int __init e820_any_mapped(unsigned long start, unsigned long end, unsigned type)
{
int i;
@@ -94,6 +97,35 @@ int __init e820_any_mapped(unsigned long
return 0;
}
+/*
+ * This function checks if the entire range <start,end> is mapped with type.
+ *
+ * Note: this function only works correct if the e820 table is sorted and
+ * not-overlapping, which is the case
+ */
+int __init e820_all_mapped(unsigned long start, unsigned long end, unsigned type)
+{
+ int i;
+ for (i = 0; i < e820.nr_map; i++) {
+ struct e820entry *ei = &e820.map[i];
+ if (type && ei->type != type)
+ continue;
+ /* is the region (part) in overlap with the current region ?*/
+ if (ei->addr >= end || ei->addr + ei->size <= start)
+ continue;
+
+ /* if the region is at the beginning of <start,end> we move
+ * start to the end of the region since it's ok until there
+ */
+ if (ei->addr <= start)
+ start = ei->addr + ei->size;
+ /* if start is now at or beyond end, we're done, full coverage */
+ if (start >= end)
+ return 1; /* we're done */
+ }
+ return 0;
+}
+
/*
* Find a free area in a specific range.
*/
Index: linux-2.6.16-mmconfig/include/asm-x86_64/e820.h
===================================================================
--- linux-2.6.16-mmconfig.orig/include/asm-x86_64/e820.h
+++ linux-2.6.16-mmconfig/include/asm-x86_64/e820.h
@@ -48,6 +48,7 @@ extern unsigned long e820_end_of_ram(voi
extern void e820_reserve_resources(void);
extern void e820_print_map(char *who);
extern int e820_any_mapped(unsigned long start, unsigned long end, unsigned type);
+extern int e820_all_mapped(unsigned long start, unsigned long end, unsigned type);
extern void e820_bootmem_free(pg_data_t *pgdat, unsigned long start,unsigned long end);
extern void e820_setup_gap(void);
This patch introduces a user for the e820_all_mapped function:
There have been several machines that don't have a working MMCONFIG, often
because of a buggy MCFG table in the ACPI bios. This patch adds a simple
sanity check that detects a whole bunch of these cases, and when it detects
it, linux now boots rather than crash-and-burns. The accuracy of this
detection can in principle be improved if there was a "is this entire range
in e820 with THIS attribute", but no such function exist and the complexity
needed for this is not really worth it; this simple check already catches
most cases anyway.
Signed-off-by: Arjan van de Ven <[email protected]>
---
arch/x86_64/pci/mmconfig.c | 10 ++++++++++
1 file changed, 10 insertions(+)
Index: linux-2.6.16-mmconfig/arch/x86_64/pci/mmconfig.c
===================================================================
--- linux-2.6.16-mmconfig.orig/arch/x86_64/pci/mmconfig.c
+++ linux-2.6.16-mmconfig/arch/x86_64/pci/mmconfig.c
@@ -9,6 +9,8 @@
#include <linux/init.h>
#include <linux/acpi.h>
#include <linux/bitmap.h>
+#include <asm/e820.h>
+
#include "pci.h"
#define MMCONFIG_APER_SIZE (256*1024*1024)
@@ -161,6 +163,14 @@ void __init pci_mmcfg_init(void)
(pci_mmcfg_config[0].base_address == 0))
return;
+ if (!e820_all_mapped(pci_mmcfg_config[0].base_address,
+ pci_mmcfg_config[0].base_address + MMCONFIG_APER_SIZE,
+ E820_RESERVED)) {
+ printk(KERN_INFO "PCI: BIOS Bug: MCFG area is not E820-reserved\n");
+ printk(KERN_INFO "PCI: Not using MMCONFIG.\n");
+ return;
+ }
+
/* RED-PEN i386 doesn't do _nocache right now */
pci_mmcfg_virt = kmalloc(sizeof(*pci_mmcfg_virt) * pci_mmcfg_config_num, GFP_KERNEL);
if (pci_mmcfg_virt == NULL) {
---
arch/i386/kernel/setup.c | 30 ++++++++++++++++++++++++++++++
arch/i386/pci/mmconfig.c | 12 ++++++++++++
include/asm-i386/e820.h | 3 +++
3 files changed, 45 insertions(+)
Index: linux-2.6.16-mmconfig/arch/i386/kernel/setup.c
===================================================================
--- linux-2.6.16-mmconfig.orig/arch/i386/kernel/setup.c
+++ linux-2.6.16-mmconfig/arch/i386/kernel/setup.c
@@ -991,6 +991,36 @@ void __init find_max_pfn(void)
}
/*
+ * This function checks if the entire range <start,end> is mapped with type.
+ *
+ * Note: this function only works correct if the e820 table is sorted and
+ * not-overlapping, which is the case
+ */
+int __init e820_all_mapped(unsigned long start, unsigned long end, unsigned type)
+{
+ int i;
+ for (i = 0; i < e820.nr_map; i++) {
+ struct e820entry *ei = &e820.map[i];
+ if (type && ei->type != type)
+ continue;
+ /* is the region (part) in overlap with the current region ?*/
+ if (ei->addr >= end || ei->addr + ei->size <= start)
+ continue;
+
+ /* if the region is at the beginning of <start,end> we move
+ * start to the end of the region since it's ok until there
+ */
+ if (ei->addr <= start)
+ start = ei->addr + ei->size;
+ /* if start is now at or beyond end, we're done, full coverage */
+ if (start >= end)
+ return 1; /* we're done */
+ }
+ return 0;
+}
+
+
+/*
* Determine low and high memory ranges:
*/
unsigned long __init find_max_low_pfn(void)
Index: linux-2.6.16-mmconfig/arch/i386/pci/mmconfig.c
===================================================================
--- linux-2.6.16-mmconfig.orig/arch/i386/pci/mmconfig.c
+++ linux-2.6.16-mmconfig/arch/i386/pci/mmconfig.c
@@ -12,6 +12,7 @@
#include <linux/pci.h>
#include <linux/init.h>
#include <linux/acpi.h>
+#include <asm/e820.h>
#include "pci.h"
#define mmcfg_virt_addr ((void __iomem *) fix_to_virt(FIX_PCIE_MCFG))
@@ -19,6 +20,9 @@
/* The base address of the last MMCONFIG device accessed */
static u32 mmcfg_last_accessed_device;
+#define MMCONFIG_APER_SIZE (256*1024*1024)
+
+
static DECLARE_BITMAP(fallback_slots, 32);
/*
@@ -183,6 +187,14 @@ void __init pci_mmcfg_init(void)
(pci_mmcfg_config[0].base_address == 0))
return;
+ if (!e820_all_mapped(pci_mmcfg_config[0].base_address,
+ pci_mmcfg_config[0].base_address + MMCONFIG_APER_SIZE,
+ E820_RESERVED)) {
+ printk(KERN_INFO "PCI: BIOS Bug: MCFG area is not E820-reserved\n");
+ printk(KERN_INFO "PCI: Not using MMCONFIG.\n");
+ return;
+ }
+
printk(KERN_INFO "PCI: Using MMCONFIG\n");
raw_pci_ops = &pci_mmcfg;
pci_probe = (pci_probe & ~PCI_PROBE_MASK) | PCI_PROBE_MMCONF;
Index: linux-2.6.16-mmconfig/include/asm-i386/e820.h
===================================================================
--- linux-2.6.16-mmconfig.orig/include/asm-i386/e820.h
+++ linux-2.6.16-mmconfig/include/asm-i386/e820.h
@@ -35,6 +35,9 @@ struct e820map {
};
extern struct e820map e820;
+
+extern int e820_all_mapped(unsigned long start, unsigned long end, unsigned type);
+
#endif/*!__ASSEMBLY__*/
#endif/*__E820_HEADER*/
On Saturday 25 March 2006 17:23, Arjan van de Ven wrote:
> Rename e820_mapped to e820_any_mapped since it tests if any part
> of the range is mapped according to the type. Later steps will introduce
> e820_all_mapped which will check if the entire range is mapped with the type.
> Both have their merit.
I merged it after fixing it all up. There were rejects. Merged the i386
changes with the x86-64 changes. And removed the bogus hunk in the MCFG
patch. Also some cosmetic changes to make the lines < 80 chars
Thanks,
-Andi