[PATCH v5 3/4] x86/boot: Get the max address from SRAT

From: Masayoshi Mizuma
Date: Fri Nov 15 2019 - 09:50:20 EST


From: Masayoshi Mizuma <m.mizuma@xxxxxxxxxxxxxx>

Get the max address from SRAT and write it into boot_params->max_addr.

Acked-by: Baoquan He <bhe@xxxxxxxxxx>
Signed-off-by: Masayoshi Mizuma <m.mizuma@xxxxxxxxxxxxxx>
---
arch/x86/boot/compressed/acpi.c | 33 +++++++++++++++++++++++++++------
1 file changed, 27 insertions(+), 6 deletions(-)

diff --git a/arch/x86/boot/compressed/acpi.c b/arch/x86/boot/compressed/acpi.c
index a0f81438a0fd..47db706656e0 100644
--- a/arch/x86/boot/compressed/acpi.c
+++ b/arch/x86/boot/compressed/acpi.c
@@ -362,17 +362,32 @@ static unsigned long get_acpi_srat_table(void)
return 0;
}

-static void subtable_parse(struct acpi_subtable_header *sub_table, int *num)
+/**
+ * subtable_parse - Cache the immovable memory regions into the
+ * immovable_mem array and update the index of the array.
+ *
+ * Return the end physical address of hotpluggable region.
+ * The system memory can be extended to the address by hotplug.
+ */
+static unsigned long subtable_parse(struct acpi_subtable_header *sub_table,
+ int *num)
{
struct acpi_srat_mem_affinity *ma;
+ unsigned long addr = 0;

ma = (struct acpi_srat_mem_affinity *)sub_table;

- if (!(ma->flags & ACPI_SRAT_MEM_HOT_PLUGGABLE) && ma->length) {
- immovable_mem[*num].start = ma->base_address;
- immovable_mem[*num].size = ma->length;
- (*num)++;
+ if (ma->length) {
+ if (ma->flags & ACPI_SRAT_MEM_HOT_PLUGGABLE)
+ addr = ma->base_address + ma->length;
+ else {
+ immovable_mem[*num].start = ma->base_address;
+ immovable_mem[*num].size = ma->length;
+ (*num)++;
+ }
}
+
+ return addr;
}

/**
@@ -391,6 +406,7 @@ int count_immovable_mem_regions(void)
struct acpi_subtable_header *sub_table;
struct acpi_table_header *table_header;
char arg[MAX_ACPI_ARG_LENGTH];
+ unsigned long max_addr = 0, addr;
int num = 0;

if (cmdline_find_option("acpi", arg, sizeof(arg)) == 3 &&
@@ -409,7 +425,9 @@ int count_immovable_mem_regions(void)
sub_table = (struct acpi_subtable_header *)table;
if (sub_table->type == ACPI_SRAT_TYPE_MEMORY_AFFINITY) {

- subtable_parse(sub_table, &num);
+ addr = subtable_parse(sub_table, &num);
+ if (addr > max_addr)
+ max_addr = addr;

if (num >= MAX_NUMNODES*2) {
debug_putstr("Too many immovable memory regions, aborting.\n");
@@ -418,6 +436,9 @@ int count_immovable_mem_regions(void)
}
table += sub_table->length;
}
+
+ boot_params->max_addr = max_addr;
+
return num;
}
#endif /* CONFIG_RANDOMIZE_BASE && CONFIG_MEMORY_HOTREMOVE */
--
2.20.1