2008-10-09 08:17:32

by bibo, mao

Subject: [patch 0/1] remove existing enclosed mtrr region

Hi,
This patch is remove enclosed mtrr region when adding new region.

Signed-off-by: bibo mao <[email protected]>

thanks
bibo,mao


kernel/cpu/mtrr/main.c | 35 +++++++++++++++++++++++++++++++----
3 files changed, 31 insertions(+), 4 deletions(-)
---------------------------------------------------------------------------------------------------------------------

diff --git a/arch/x86/kernel/cpu/mtrr/main.c b/arch/x86/kernel/cpu/mtrr/main.c
index 6a1e278..6e212f3 100644
--- a/arch/x86/kernel/cpu/mtrr/main.c
+++ b/arch/x86/kernel/cpu/mtrr/main.c
@@ -303,7 +303,7 @@ static void set_mtrr(unsigned int reg, unsigned long base,
int mtrr_add_page(unsigned long base, unsigned long size,
unsigned int type, bool increment)
{
- int i, replace, error;
+ int i, j, replace, error;
mtrr_type ltype;
unsigned long lbase, lsize;

@@ -351,7 +351,7 @@ int mtrr_add_page(unsigned long base, unsigned long size,
if (base <= lbase && base + size - 1 >= lbase + lsize - 1) {
/* New region encloses an existing region */
if (type == ltype) {
- replace = replace == -1 ? i : -2;
+ replace = i;
continue;
}
else if (types_compatible(type, ltype))
@@ -391,6 +391,20 @@ int mtrr_add_page(unsigned long base, unsigned long size,
set_mtrr(replace, 0, 0, 0);
mtrr_usage_table[replace] = 0;
}
+
+ /* remove existing enclosed region */
+ for (j = 0; j < num_var_ranges; ++j) {
+ if (i == j)
+ continue;
+ mtrr_if->get(j, &lbase, &lsize, &ltype);
+ if (lsize && type == ltype && base <= lbase
+ && base + size - 1 >= lbase + lsize - 1) {
+ /* New region encloses an existing region */
+ mtrr_usage_table[i] += mtrr_usage_table[j];
+ set_mtrr(j, 0, 0, 0);
+ mtrr_usage_table[j]=0;
+ }
+ }
}
} else
printk(KERN_INFO "mtrr: no more MTRRs available\n");