Re: [PATCH 04/21] MIPS memblock: Alter user-defined memory parameter parser

[Marcin Nowakowski]

Hi Serge,

On 19.12.2016 03:07, Serge Semin wrote:

Both new memblock and boot_mem_map subsystems need to be fully
cleared before a new memory region is added. So the early parser is
correspondingly modified.

Signed-off-by: Serge Semin <fancer.lan...@gmail.com>
---
 arch/mips/kernel/setup.c | 67 +++++++++++++++++-------------
 1 file changed, 37 insertions(+), 30 deletions(-)

diff --git a/arch/mips/kernel/setup.c b/arch/mips/kernel/setup.c
index 9da6f8a..789aafe 100644
--- a/arch/mips/kernel/setup.c
+++ b/arch/mips/kernel/setup.c
@@ -229,6 +229,43 @@ static void __init print_memory_map(void)
 }

 /*
+ * Parse "mem=size@start" parameter rewriting a defined memory map
+ * We look for mem=size@start, where start and size are "value[KkMm]"
+ */
+static int __init early_parse_mem(char *p)
+{
+       static int usermem;

usermem variable seems unnecessary now and could easily be removed?

+       phys_addr_t start, size;
+
+       start = PHYS_OFFSET;
+       size = memparse(p, &p);
+       if (*p == '@')
+               start = memparse(p + 1, &p);
+
+       /*
+        * If a user specifies memory size, we blow away any automatically
+        * generated regions.
+        */
+       if (usermem == 0) {
+               phys_addr_t ram_start = memblock_start_of_DRAM();
+               phys_addr_t ram_end = memblock_end_of_DRAM() - ram_start;
+
+               pr_notice("Discard memory layout %pa - %pa",
+                         &ram_start, &ram_end);

missing \n in printk

+               memblock_remove(ram_start, ram_end - ram_start);
+               boot_mem_map.nr_map = 0;
+               usermem = 1;
+       }
+       pr_notice("Add userdefined memory region %08zx @ %pa",
+                 (size_t)size, &start);

ditto

+       add_memory_region(start, size, BOOT_MEM_RAM);
+       return 0;
+}
+early_param("mem", early_parse_mem);
+
+/*
  * Manage initrd
  */
 #ifdef CONFIG_BLK_DEV_INITRD
@@ -613,31 +650,6 @@ static void __init bootmem_init(void)
  * initialization hook for anything else was introduced.
  */

-static int usermem __initdata;
-
-static int __init early_parse_mem(char *p)
-{
-       phys_addr_t start, size;
-
-       /*
-        * If a user specifies memory size, we
-        * blow away any automatically generated
-        * size.
-        */
-       if (usermem == 0) {
-               boot_mem_map.nr_map = 0;
-               usermem = 1;
-       }
-       start = 0;
-       size = memparse(p, &p);
-       if (*p == '@')
-               start = memparse(p + 1, &p);
-
-       add_memory_region(start, size, BOOT_MEM_RAM);
-       return 0;
-}
-early_param("mem", early_parse_mem);
-
 #ifdef CONFIG_PROC_VMCORE
 unsigned long setup_elfcorehdr, setup_elfcorehdr_size;
 static int __init early_parse_elfcorehdr(char *p)
@@ -797,11 +809,6 @@ static void __init arch_mem_init(char **cmdline_p)

        parse_early_param();

-       if (usermem) {
-               pr_info("User-defined physical RAM map:\n");
-               print_memory_map();
-       }
-
        bootmem_init();
 #ifdef CONFIG_PROC_VMCORE
        if (setup_elfcorehdr && setup_elfcorehdr_size) {

Regards,
Marcin