[patch 01/11] PAT x86: Make acpi/other drivers map memory instead of assuming identity map
From: venkatesh . pallipadi
Date: Thu Jan 10 2008 - 13:55:49 EST
This series is heavily derived from the PAT patchset by Eric Biederman and
Andi Kleen.
http://www.firstfloor.org/pub/ak/x86_64/pat/
This patchset is a followup of "PAT support for X86_64"
http://www.ussg.iu.edu/hypermail/linux/kernel/0712.1/2268.html
Things changed from the above (Dec 13 2007) version:
* PAT mappings now used are - (0,WB) (1,WT) (2,WC) (3,UC).
* Covers both i386 and x86_64.
* Resolve the /sysfs issue by exporting wc and uc interfaces.
* Piggyback PAT initialization on existing MTRR initialization as they
have same setup rules.
* Avoid early table allocation problem for x86_64 by doing the reserved
region pruning later in the boot. Handle both memory identity mapping and
kernel test mapping.
* Handle fork() and /dev/mem mapping and unmapping cases.
This patch:
Some boot code has assumptions about entire memory being mapped in identity
mapping. Fix them to use some form of mapping instead. Places fixed below:
* Generic __acpi_map_table
* Looking for RSD PTR at boot time
* Looking for mp table
* get_bios_ebda and ebda size
* pci-calgary (Compile tested only. Will be great if someone who has this
hardware can verify that this change works fine)
(This patch is testable as a standalone patch)
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@xxxxxxxxx>
Signed-off-by: Suresh Siddha <suresh.b.siddha@xxxxxxxxx>
---
Patchset is against Ingo's x86 branch from 2 days ago. Will need some merging
effort with Andi's CPA changes and few other changes like pgtable.h unification.
Index: linux-2.6.git/arch/x86/kernel/acpi/boot.c
===================================================================
--- linux-2.6.git.orig/arch/x86/kernel/acpi/boot.c 2008-01-08 03:31:31.000000000 -0800
+++ linux-2.6.git/arch/x86/kernel/acpi/boot.c 2008-01-08 03:43:46.000000000 -0800
@@ -105,16 +105,20 @@
#ifdef CONFIG_X86_64
-/* rely on all ACPI tables being in the direct mapping */
char *__acpi_map_table(unsigned long phys_addr, unsigned long size)
{
if (!phys_addr || !size)
return NULL;
- if (phys_addr+size <= (end_pfn_map << PAGE_SHIFT) + PAGE_SIZE)
- return __va(phys_addr);
+ return early_ioremap(phys_addr, size);
+}
- return NULL;
+void __acpi_unmap_table(void * addr, unsigned long size)
+{
+ if (!addr || !size)
+ return;
+
+ early_iounmap(addr, size);
}
#else
@@ -158,6 +162,11 @@
return ((unsigned char *)base + offset);
}
+
+void __acpi_unmap_table(void * addr, unsigned long size)
+{
+}
+
#endif
#ifdef CONFIG_PCI_MMCONFIG
@@ -586,17 +595,23 @@
{
unsigned long offset = 0;
unsigned long sig_len = sizeof("RSD PTR ") - 1;
+ char * virt_addr;
+ virt_addr = __acpi_map_table(start, length);
+ if (!virt_addr)
+ return 0;
/*
* Scan all 16-byte boundaries of the physical memory region for the
* RSDP signature.
*/
for (offset = 0; offset < length; offset += 16) {
- if (strncmp((char *)(phys_to_virt(start) + offset), "RSD PTR ", sig_len))
+ if (strncmp(virt_addr + offset, "RSD PTR ", sig_len))
continue;
+ __acpi_unmap_table(virt_addr, length);
return (start + offset);
}
+ __acpi_unmap_table(virt_addr, length);
return 0;
}
Index: linux-2.6.git/drivers/acpi/osl.c
===================================================================
--- linux-2.6.git.orig/drivers/acpi/osl.c 2008-01-08 03:31:31.000000000 -0800
+++ linux-2.6.git/drivers/acpi/osl.c 2008-01-08 03:43:46.000000000 -0800
@@ -231,6 +231,8 @@
{
if (acpi_gbl_permanent_mmap) {
iounmap(virt);
+ } else {
+ __acpi_unmap_table(virt, size);
}
}
EXPORT_SYMBOL_GPL(acpi_os_unmap_memory);
Index: linux-2.6.git/include/linux/acpi.h
===================================================================
--- linux-2.6.git.orig/include/linux/acpi.h 2008-01-08 03:31:38.000000000 -0800
+++ linux-2.6.git/include/linux/acpi.h 2008-01-08 03:43:46.000000000 -0800
@@ -79,6 +79,7 @@
typedef int (*acpi_table_entry_handler) (struct acpi_subtable_header *header, const unsigned long end);
char * __acpi_map_table (unsigned long phys_addr, unsigned long size);
+void __acpi_unmap_table (void * addr, unsigned long size);
unsigned long acpi_find_rsdp (void);
int acpi_boot_init (void);
int acpi_boot_table_init (void);
Index: linux-2.6.git/arch/x86/kernel/mpparse_64.c
===================================================================
--- linux-2.6.git.orig/arch/x86/kernel/mpparse_64.c 2008-01-08 03:31:31.000000000 -0800
+++ linux-2.6.git/arch/x86/kernel/mpparse_64.c 2008-01-08 03:43:46.000000000 -0800
@@ -29,6 +29,7 @@
#include <asm/io_apic.h>
#include <asm/proto.h>
#include <asm/acpi.h>
+#include <asm/bios_ebda.h>
/* Have we found an MP table */
int smp_found_config;
@@ -535,9 +536,12 @@
static int __init smp_scan_config (unsigned long base, unsigned long length)
{
extern void __bad_mpf_size(void);
- unsigned int *bp = phys_to_virt(base);
+ unsigned int *bp = (unsigned int *)__acpi_map_table(base, length);
struct intel_mp_floating *mpf;
+ if (!bp)
+ return 0;
+
Dprintk("Scan SMP from %p for %ld bytes.\n", bp,length);
if (sizeof(*mpf) != 16)
__bad_mpf_size();
@@ -555,11 +559,13 @@
if (mpf->mpf_physptr)
reserve_bootmem_generic(mpf->mpf_physptr, PAGE_SIZE);
mpf_found = mpf;
+ __acpi_unmap_table((char *)bp, length);
return 1;
}
bp += 4;
length -= 16;
}
+ __acpi_unmap_table((char *)bp, length);
return 0;
}
@@ -592,11 +598,11 @@
* should be fixed.
*/
- address = *(unsigned short *)phys_to_virt(0x40E);
- address <<= 4;
- if (smp_scan_config(address, 0x1000))
+ address = get_bios_ebda();
+ if (address && smp_scan_config(address, 0x1000))
return;
+
/* If we have come this far, we did not find an MP table */
printk(KERN_INFO "No mptable found.\n");
}
Index: linux-2.6.git/arch/x86/mm/init_64.c
===================================================================
--- linux-2.6.git.orig/arch/x86/mm/init_64.c 2008-01-08 03:41:30.000000000 -0800
+++ linux-2.6.git/arch/x86/mm/init_64.c 2008-01-08 03:43:46.000000000 -0800
@@ -208,7 +208,7 @@
}
/* Must run before zap_low_mappings */
-__meminit void *early_ioremap(unsigned long addr, unsigned long size)
+void *early_ioremap(unsigned long addr, unsigned long size)
{
unsigned long vaddr;
pmd_t *pmd, *last_pmd;
@@ -237,7 +237,7 @@
}
/* To avoid virtual aliases later */
-__meminit void early_iounmap(void *addr, unsigned long size)
+void early_iounmap(void *addr, unsigned long size)
{
unsigned long vaddr;
pmd_t *pmd;
Index: linux-2.6.git/include/asm-x86/rio.h
===================================================================
--- linux-2.6.git.orig/include/asm-x86/rio.h 2008-01-08 03:41:30.000000000 -0800
+++ linux-2.6.git/include/asm-x86/rio.h 2008-01-08 03:43:46.000000000 -0800
@@ -8,6 +8,8 @@
#ifndef __ASM_RIO_H
#define __ASM_RIO_H
+#include <asm/bios_ebda.h>
+
#define RIO_TABLE_VERSION 3
struct rio_table_hdr {
@@ -60,15 +62,4 @@
ALT_CALGARY = 5, /* Second Planar Calgary */
};
-/*
- * there is a real-mode segmented pointer pointing to the
- * 4K EBDA area at 0x40E.
- */
-static inline unsigned long get_bios_ebda(void)
-{
- unsigned long address = *(unsigned short *)phys_to_virt(0x40EUL);
- address <<= 4;
- return address;
-}
-
#endif /* __ASM_RIO_H */
Index: linux-2.6.git/arch/x86/kernel/mpparse_32.c
===================================================================
--- linux-2.6.git.orig/arch/x86/kernel/mpparse_32.c 2008-01-08 03:41:30.000000000 -0800
+++ linux-2.6.git/arch/x86/kernel/mpparse_32.c 2008-01-08 03:43:46.000000000 -0800
@@ -27,11 +27,11 @@
#include <asm/mtrr.h>
#include <asm/mpspec.h>
#include <asm/io_apic.h>
+#include <asm/bios_ebda.h>
#include <mach_apic.h>
#include <mach_apicdef.h>
#include <mach_mpparse.h>
-#include <bios_ebda.h>
/* Have we found an MP table */
int smp_found_config;
@@ -718,9 +718,12 @@
static int __init smp_scan_config (unsigned long base, unsigned long length)
{
- unsigned long *bp = phys_to_virt(base);
+ unsigned long *bp = (unsigned long *)__acpi_map_table(base, length);
struct intel_mp_floating *mpf;
+ if (!bp)
+ return 0;
+
Dprintk("Scan SMP from %p for %ld bytes.\n", bp,length);
if (sizeof(*mpf) != 16)
printk("Error: MPF size\n");
@@ -755,11 +758,13 @@
}
mpf_found = mpf;
+ __acpi_unmap_table((char *)bp, length);
return 1;
}
bp += 4;
length -= 16;
}
+ __acpi_unmap_table((char *)bp, length);
return 0;
}
Index: linux-2.6.git/arch/x86/kernel/pci-calgary_64.c
===================================================================
--- linux-2.6.git.orig/arch/x86/kernel/pci-calgary_64.c 2008-01-08 03:41:30.000000000 -0800
+++ linux-2.6.git/arch/x86/kernel/pci-calgary_64.c 2008-01-08 03:43:46.000000000 -0800
@@ -1180,6 +1180,7 @@
}
}
+ early_iounmap((void *)rio_table_hdr, sizeof(struct rio_table_hdr));
return 0;
error:
@@ -1188,6 +1189,7 @@
if (bus_info[bus].bbar)
iounmap(bus_info[bus].bbar);
+ early_iounmap((void *)rio_table_hdr, sizeof(struct rio_table_hdr));
return ret;
}
@@ -1337,7 +1339,8 @@
int bus;
void *tbl;
int calgary_found = 0;
- unsigned long ptr;
+ unsigned long addr;
+ unsigned short *ptr;
unsigned int offset, prev_offset;
int ret;
@@ -1356,7 +1359,9 @@
printk(KERN_DEBUG "Calgary: detecting Calgary via BIOS EBDA area\n");
- ptr = (unsigned long)phys_to_virt(get_bios_ebda());
+ addr = get_bios_ebda();
+ if (!addr)
+ return;
rio_table_hdr = NULL;
prev_offset = 0;
@@ -1366,14 +1371,22 @@
* Only parse up until the offset increases:
*/
while (offset > prev_offset) {
+ ptr = early_ioremap(addr + offset, 4);
+ if (!ptr)
+ break;
+
/* The block id is stored in the 2nd word */
- if (*((unsigned short *)(ptr + offset + 2)) == 0x4752){
+ if (ptr[1] == 0x4752){
+ early_iounmap(ptr, 4);
/* set the pointer past the offset & block id */
- rio_table_hdr = (struct rio_table_hdr *)(ptr + offset + 4);
+ ptr = early_ioremap(addr + offset + 4,
+ sizeof(struct rio_table_hdr));
+ rio_table_hdr = (struct rio_table_hdr *)ptr;
break;
}
prev_offset = offset;
- offset = *((unsigned short *)(ptr + offset));
+ offset = ptr[0];
+ early_iounmap(ptr, 4);
}
if (!rio_table_hdr) {
printk(KERN_DEBUG "Calgary: Unable to locate Rio Grande table "
@@ -1384,6 +1397,8 @@
ret = build_detail_arrays();
if (ret) {
printk(KERN_DEBUG "Calgary: build_detail_arrays ret %d\n", ret);
+ early_iounmap((void *)rio_table_hdr,
+ sizeof(struct rio_table_hdr));
return;
}
@@ -1423,6 +1438,10 @@
printk(KERN_INFO "PCI-DMA: Calgary TCE table spec is %d, "
"CONFIG_IOMMU_DEBUG is %s.\n", specified_table_size,
debugging ? "enabled" : "disabled");
+ /* rio_table_hdr will be unmapped in calgary_locate_bbars() */
+ } else {
+ early_iounmap((void *)rio_table_hdr,
+ sizeof(struct rio_table_hdr));
}
return;
@@ -1433,6 +1452,7 @@
if (info->tce_space)
free_tce_table(info->tce_space);
}
+ early_iounmap((void *)rio_table_hdr, sizeof(struct rio_table_hdr));
}
int __init calgary_iommu_init(void)
Index: linux-2.6.git/arch/x86/kernel/setup_32.c
===================================================================
--- linux-2.6.git.orig/arch/x86/kernel/setup_32.c 2008-01-08 03:41:30.000000000 -0800
+++ linux-2.6.git/arch/x86/kernel/setup_32.c 2008-01-08 03:43:46.000000000 -0800
@@ -61,7 +61,7 @@
#include <asm/io.h>
#include <asm/vmi.h>
#include <setup_arch.h>
-#include <bios_ebda.h>
+#include <asm/bios_ebda.h>
#include <asm/cacheflush.h>
/* This value is set up by the early boot code to point to the value
Index: linux-2.6.git/arch/x86/kernel/setup_64.c
===================================================================
--- linux-2.6.git.orig/arch/x86/kernel/setup_64.c 2008-01-08 03:41:30.000000000 -0800
+++ linux-2.6.git/arch/x86/kernel/setup_64.c 2008-01-08 03:47:57.000000000 -0800
@@ -62,6 +62,7 @@
#include <asm/sections.h>
#include <asm/dmi.h>
#include <asm/cacheflush.h>
+#include <asm/bios_ebda.h>
#include <asm/mce.h>
#include <asm/ds.h>
@@ -243,31 +244,36 @@
{}
#endif
-#define EBDA_ADDR_POINTER 0x40E
-
unsigned __initdata ebda_addr;
unsigned __initdata ebda_size;
static void discover_ebda(void)
{
+ unsigned short *ptr;
/*
* there is a real-mode segmented pointer pointing to the
* 4K EBDA area at 0x40E
*/
- ebda_addr = *(unsigned short *)__va(EBDA_ADDR_POINTER);
/*
* There can be some situations, like paravirtualized guests,
* in which there is no available ebda information. In such
* case, just skip it
*/
+
+ ebda_addr = get_bios_ebda();
if (!ebda_addr) {
ebda_size = 0;
return;
}
- ebda_addr <<= 4;
-
- ebda_size = *(unsigned short *)__va(ebda_addr);
+ ptr = (unsigned short *)__acpi_map_table(ebda_addr, 2);
+ if (!ptr) {
+ ebda_addr = 0;
+ ebda_size = 0;
+ return;
+ }
+ ebda_size = *(unsigned short *)ptr;
+ __acpi_unmap_table((char *)ptr, 2);
/* Round EBDA up to pages */
if (ebda_size == 0)
Index: linux-2.6.git/include/asm-x86/bios_ebda.h
===================================================================
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ linux-2.6.git/include/asm-x86/bios_ebda.h 2008-01-08 03:43:46.000000000 -0800
@@ -0,0 +1,26 @@
+
+#ifndef _BIOS_EBDA_H
+#define _BIOS_EBDA_H
+
+#include <linux/acpi.h>
+
+/*
+ * there is a real-mode segmented pointer pointing to the
+ * 4K EBDA area at 0x40E.
+ */
+static inline unsigned long get_bios_ebda(void)
+{
+ unsigned short *bp;
+ unsigned long address;
+ bp = (unsigned short *)__acpi_map_table(0x40EUL, 2);
+ if (!bp)
+ return 0;
+
+ address = *bp;
+ address <<= 4;
+ __acpi_unmap_table((char *)bp, 2);
+
+ return address;
+}
+
+#endif /* _MACH_BIOS_EBDA_H */
Index: linux-2.6.git/include/asm-x86/mach-default/bios_ebda.h
===================================================================
--- linux-2.6.git.orig/include/asm-x86/mach-default/bios_ebda.h 2008-01-08 03:31:38.000000000 -0800
+++ /dev/null 1970-01-01 00:00:00.000000000 +0000
@@ -1,15 +0,0 @@
-#ifndef _MACH_BIOS_EBDA_H
-#define _MACH_BIOS_EBDA_H
-
-/*
- * there is a real-mode segmented pointer pointing to the
- * 4K EBDA area at 0x40E.
- */
-static inline unsigned int get_bios_ebda(void)
-{
- unsigned int address = *(unsigned short *)phys_to_virt(0x40E);
- address <<= 4;
- return address; /* 0 means none */
-}
-
-#endif /* _MACH_BIOS_EBDA_H */
--
--
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