From 5dca6a1bb014875a17289fdaae8c31e0a3641c99 Mon Sep 17 00:00:00 2001 From: Yinghai Lu Date: Tue, 18 Mar 2008 16:44:19 -0700 Subject: [PATCH] x86: trim mtrr don't close gap for resource allocation. fix the bug reported here: http://bugzilla.kernel.org/show_bug.cgi?id=10232 use update_memory_range() instead of add_memory_range() directly to avoid closing the gap. ( the new code only affects and runs on systems where the MTRR workaround triggers. ) Signed-off-by: Yinghai Lu Signed-off-by: Ingo Molnar Signed-off-by: Thomas Gleixner --- arch/x86/kernel/cpu/mtrr/main.c | 3 ++- arch/x86/kernel/e820_32.c | 26 ++++++++++++++++++++++++++ arch/x86/kernel/e820_64.c | 27 +++++++++++++++++++++++++++ include/asm-x86/e820_32.h | 2 ++ include/asm-x86/e820_64.h | 2 ++ 5 files changed, 59 insertions(+), 1 deletion(-) diff --git a/arch/x86/kernel/cpu/mtrr/main.c b/arch/x86/kernel/cpu/mtrr/main.c index be83336fdd..a6450b3ae7 100644 --- a/arch/x86/kernel/cpu/mtrr/main.c +++ b/arch/x86/kernel/cpu/mtrr/main.c @@ -711,7 +711,8 @@ int __init mtrr_trim_uncached_memory(unsigned long end_pfn) trim_size = end_pfn; trim_size <<= PAGE_SHIFT; trim_size -= trim_start; - add_memory_region(trim_start, trim_size, E820_RESERVED); + update_memory_range(trim_start, trim_size, E820_RAM, + E820_RESERVED); update_e820(); return 1; } diff --git a/arch/x86/kernel/e820_32.c b/arch/x86/kernel/e820_32.c index 4e16ef4a26..80444c5c9b 100644 --- a/arch/x86/kernel/e820_32.c +++ b/arch/x86/kernel/e820_32.c @@ -749,6 +749,32 @@ static int __init parse_memmap(char *arg) return 0; } early_param("memmap", parse_memmap); +void __init update_memory_range(u64 start, u64 size, unsigned old_type, + unsigned new_type) +{ + int i; + + BUG_ON(old_type == new_type); + + for (i = 0; i < e820.nr_map; i++) { + struct e820entry *ei = &e820.map[i]; + u64 final_start, final_end; + if (ei->type != old_type) + continue; + /* totally covered? */ + if (ei->addr >= start && ei->size <= size) { + ei->type = new_type; + continue; + } + /* partially covered */ + final_start = max(start, ei->addr); + final_end = min(start + size, ei->addr + ei->size); + if (final_start >= final_end) + continue; + add_memory_region(final_start, final_end - final_start, + new_type); + } +} void __init update_e820(void) { u8 nr_map; diff --git a/arch/x86/kernel/e820_64.c b/arch/x86/kernel/e820_64.c index 9f65b4cc32..9be6971260 100644 --- a/arch/x86/kernel/e820_64.c +++ b/arch/x86/kernel/e820_64.c @@ -744,6 +744,33 @@ void __init finish_e820_parsing(void) } } +void __init update_memory_range(u64 start, u64 size, unsigned old_type, + unsigned new_type) +{ + int i; + + BUG_ON(old_type == new_type); + + for (i = 0; i < e820.nr_map; i++) { + struct e820entry *ei = &e820.map[i]; + u64 final_start, final_end; + if (ei->type != old_type) + continue; + /* totally covered? */ + if (ei->addr >= start && ei->size <= size) { + ei->type = new_type; + continue; + } + /* partially covered */ + final_start = max(start, ei->addr); + final_end = min(start + size, ei->addr + ei->size); + if (final_start >= final_end) + continue; + add_memory_region(final_start, final_end - final_start, + new_type); + } +} + void __init update_e820(void) { u8 nr_map; diff --git a/include/asm-x86/e820_32.h b/include/asm-x86/e820_32.h index f1da7ebd19..e7207a6de3 100644 --- a/include/asm-x86/e820_32.h +++ b/include/asm-x86/e820_32.h @@ -28,6 +28,8 @@ extern void find_max_pfn(void); extern void register_bootmem_low_pages(unsigned long max_low_pfn); extern void add_memory_region(unsigned long long start, unsigned long long size, int type); +extern void update_memory_range(u64 start, u64 size, unsigned old_type, + unsigned new_type); extern void e820_register_memory(void); extern void limit_regions(unsigned long long size); extern void print_memory_map(char *who); diff --git a/include/asm-x86/e820_64.h b/include/asm-x86/e820_64.h index a560c4f5d5..22ede73ae7 100644 --- a/include/asm-x86/e820_64.h +++ b/include/asm-x86/e820_64.h @@ -18,6 +18,8 @@ extern unsigned long find_e820_area(unsigned long start, unsigned long end, unsigned size, unsigned long align); extern void add_memory_region(unsigned long start, unsigned long size, int type); +extern void update_memory_range(u64 start, u64 size, unsigned old_type, + unsigned new_type); extern void setup_memory_region(void); extern void contig_e820_setup(void); extern unsigned long e820_end_of_ram(void); -- 2.39.5