[PATCH v4 2/4] x86/boot/KASLR: Switch to pass struct mem_vector to process_e820_entry()

From: Baoquan He
Date: Sun Jul 09 2017 - 08:38:19 EST


This makes process_e820_entry() be able to process any kind of memory
region.

Signed-off-by: Baoquan He <bhe@xxxxxxxxxx>
---
arch/x86/boot/compressed/kaslr.c | 25 ++++++++++++++-----------
1 file changed, 14 insertions(+), 11 deletions(-)

diff --git a/arch/x86/boot/compressed/kaslr.c b/arch/x86/boot/compressed/kaslr.c
index 1485f48aeda1..36ff9f729c43 100644
--- a/arch/x86/boot/compressed/kaslr.c
+++ b/arch/x86/boot/compressed/kaslr.c
@@ -479,31 +479,31 @@ static unsigned long slots_fetch_random(void)
return 0;
}

-static void process_e820_entry(struct boot_e820_entry *entry,
+static void process_e820_entry(struct mem_vector *entry,
unsigned long minimum,
unsigned long image_size)
{
struct mem_vector region, overlap;
struct slot_area slot_area;
unsigned long start_orig, end;
- struct boot_e820_entry cur_entry;
+ struct mem_vector cur_entry;

/* On 32-bit, ignore entries entirely above our maximum. */
- if (IS_ENABLED(CONFIG_X86_32) && entry->addr >= KERNEL_IMAGE_SIZE)
+ if (IS_ENABLED(CONFIG_X86_32) && entry->start >= KERNEL_IMAGE_SIZE)
return;

/* Ignore entries entirely below our minimum. */
- if (entry->addr + entry->size < minimum)
+ if (entry->start + entry->size < minimum)
return;

/* Ignore entries above memory limit */
- end = min(entry->size + entry->addr, mem_limit);
- if (entry->addr >= end)
+ end = min(entry->size + entry->start, mem_limit);
+ if (entry->start >= end)
return;
- cur_entry.addr = entry->addr;
- cur_entry.size = end - entry->addr;
+ cur_entry.start = entry->start;
+ cur_entry.size = end - entry->start;

- region.start = cur_entry.addr;
+ region.start = cur_entry.start;
region.size = cur_entry.size;

/* Give up if slot area array is full. */
@@ -518,7 +518,7 @@ static void process_e820_entry(struct boot_e820_entry *entry,
region.start = ALIGN(region.start, CONFIG_PHYSICAL_ALIGN);

/* Did we raise the address above this e820 region? */
- if (region.start > cur_entry.addr + cur_entry.size)
+ if (region.start > cur_entry.start + cur_entry.size)
return;

/* Reduce size by any delta from the original address. */
@@ -562,6 +562,7 @@ static void process_e820_entries(unsigned long minimum,
unsigned long image_size)
{
int i;
+ struct mem_vector region;
struct boot_e820_entry *entry;

/* Verify potential e820 positions, appending to slots list. */
@@ -570,7 +571,9 @@ static void process_e820_entries(unsigned long minimum,
/* Skip non-RAM entries. */
if (entry->type != E820_TYPE_RAM)
continue;
- process_e820_entry(entry, minimum, image_size);
+ region.start = entry->addr;
+ region.size = entry->size;
+ process_e820_entry(&region, minimum, image_size);
if (slot_area_index == MAX_SLOT_AREA) {
debug_putstr("Aborted e820 scan (slot_areas full)!\n");
break;
--
2.5.5