Re: [PATCH v15 5/6] x86/boot: Parse SRAT address from RSDP and store immovable memory

Chao Fan
2019-01-18T01:15:48Z

On Thu, Jan 17, 2019 at 04:27:51PM +0100, Borislav Petkov wrote:
>On Thu, Jan 17, 2019 at 11:20:27AM +0800, Chao Fan wrote:
>> I have changed as you suggested, looks clear without type cast, and
>> we need some variable as long to calculate the address, and at same
>> time as the struct pointer to find it's length, so I change as below,
>> and get_acpi_srat_table() return an unsigned long.
>> How do you think of that.
>>
>> int get_immovable_mem_num(void)
>
>I'd call that
>
>int count_immovable_mem_regions(void)
>
>or
>
>int enumerate_immovable_regions(void)
>
>or so and put a comment above it explaining what it does and what it
>returns.
>
>"mem_num" is not clear what it is.
>

Sounds good, I will rename it.

>> {
>> unsigned long table_addr, table_end, table;
>> struct acpi_table_header *table_header;
>> struct acpi_subtable_header *sub_table;
>> char arg[MAX_ACPI_ARG_LENGTH];
>> int num = 0;
>>
>> if (cmdline_find_option("acpi", arg, sizeof(arg)) == 3 &&
>> !strncmp(arg, "off", 3))
>> return;
>>
>> table_addr = get_acpi_srat_table();
>> if (!table_addr)
>> return;
>>
>> table_header = (struct acpi_table_header *)table_addr;
>> table_end = table_addr + table_header->length;
>> table = table_addr + sizeof(struct acpi_table_srat);
>>
>> while (table + sizeof(struct acpi_subtable_header) < table_end) {
>> sub_table = (struct acpi_subtable_header *)table;
>> if (sub_table->type == ACPI_SRAT_TYPE_MEMORY_AFFINITY) {
>> struct acpi_srat_mem_affinity *ma;
>>
>> ma = (struct acpi_srat_mem_affinity *)table;
>> if (!(ma->flags & ACPI_SRAT_MEM_HOT_PLUGGABLE)) {
>> immovable_mem[num].start = ma->base_address;
>> immovable_mem[num].size = ma->length;
>> num++;
>> }
>>
>> if (num >= MAX_NUMNODES*2) {
>> debug_putstr("Too many immovable memory regions, aborting.\n");
>> return 0;
>> }
>> }
>> table += sub_table->length;
>> }
>> return num;
>> }
>
>That looks clean.

Then I will change based on that.

Thanks,
Chao Fan

>
>Thx.
>
>--
>Regards/Gruss,
> Boris.
>
>Good mailing practices for 400: avoid top-posting and trim the reply.
>
>