Re: [PATCH v4 1/2] arm64: Get rid of __early_init_dt_declare_initrd()

From: Florian Fainelli
Date: Mon Oct 29 2018 - 12:51:52 EST


Hi Mike,

On 10/27/18 2:13 AM, Mike Rapoport wrote:
> Hi Florian,
>
> On Fri, Oct 26, 2018 at 03:39:50PM -0700, Florian Fainelli wrote:
>> ARM64 is the only architecture that re-defines
>> __early_init_dt_declare_initrd() in order for that function to populate
>> initrd_start/initrd_end with physical addresses instead of virtual
>> addresses. Instead of having an override, just get rid of that
>> implementation and perform the virtual to physical conversion of these
>> addresses in arm64_memblock_init() where relevant.
>>
>> Signed-off-by: Florian Fainelli <f.fainelli@xxxxxxxxx>
>> ---
>> arch/arm64/include/asm/memory.h | 8 --------
>> arch/arm64/mm/init.c | 26 ++++++++++++++++----------
>> 2 files changed, 16 insertions(+), 18 deletions(-)
>>
>> diff --git a/arch/arm64/include/asm/memory.h b/arch/arm64/include/asm/memory.h
>> index b96442960aea..dc3ca21ba240 100644
>> --- a/arch/arm64/include/asm/memory.h
>> +++ b/arch/arm64/include/asm/memory.h
>> @@ -168,14 +168,6 @@
>> #define IOREMAP_MAX_ORDER (PMD_SHIFT)
>> #endif
>>
>> -#ifdef CONFIG_BLK_DEV_INITRD
>> -#define __early_init_dt_declare_initrd(__start, __end) \
>> - do { \
>> - initrd_start = (__start); \
>> - initrd_end = (__end); \
>> - } while (0)
>> -#endif
>> -
>> #ifndef __ASSEMBLY__
>>
>> #include <linux/bitops.h>
>> diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
>> index 3cf87341859f..98ff0f7a0f7a 100644
>> --- a/arch/arm64/mm/init.c
>> +++ b/arch/arm64/mm/init.c
>> @@ -364,6 +364,9 @@ static void __init fdt_enforce_memory_region(void)
>> void __init arm64_memblock_init(void)
>> {
>> const s64 linear_region_size = -(s64)PAGE_OFFSET;
>> + unsigned long __maybe_unused phys_initrd_size;
>> + u64 __maybe_unused phys_initrd_start;
>> + u64 __maybe_unused base, size;
>>
>> /* Handle linux,usable-memory-range property */
>> fdt_enforce_memory_region();
>> @@ -414,8 +417,11 @@ void __init arm64_memblock_init(void)
>> * initrd to become inaccessible via the linear mapping.
>> * Otherwise, this is a no-op
>> */
>> - u64 base = initrd_start & PAGE_MASK;
>> - u64 size = PAGE_ALIGN(initrd_end) - base;
>> + phys_initrd_start = __pa(initrd_start);
>> + phys_initrd_size = __pa(initrd_end) - phys_initrd_start;
>
> If initrd_{start,end} are defined by the command line they already would be
> physical addresses.

Yes indeed.

>
>> +
>> + base = phys_initrd_start & PAGE_MASK;
>> + size = PAGE_ALIGN(phys_initrd_size);
>>
>> /*
>> * We can only add back the initrd memory if we don't end up
>> @@ -459,15 +465,15 @@ void __init arm64_memblock_init(void)
>> * pagetables with memblock.
>> */
>> memblock_reserve(__pa_symbol(_text), _end - _text);
>> -#ifdef CONFIG_BLK_DEV_INITRD
>> - if (initrd_start) {
>> - memblock_reserve(initrd_start, initrd_end - initrd_start);
>> -
>> - /* the generic initrd code expects virtual addresses */
>> - initrd_start = __phys_to_virt(initrd_start);
>> - initrd_end = __phys_to_virt(initrd_end);
>> + if (IS_ENABLED(CONFIG_BLK_DEV_INITRD) && initrd_start) {
>> + memblock_reserve(phys_initrd_start, phys_initrd_size);
>
> this is not needed, as we do memblock_reserve() for the same area earlier.

Humm, yes, actually we made sure before that we called
memblock_reserve() against a properly page aligned region, unlike the
one below.

>
> What do you think of my version (below)?

Looks good to me, thanks for making those fixes, I will send that
shortly along with patch #2 if that sounds reasonable to you.

>
>> + /*
>> + * initrd_below_start_ok can be changed by
>> + * __early_init_dt_declare_initrd(), set it back to what
>> + * we want here.
>> + */
>> + initrd_below_start_ok = 0;
>> }
>> -#endif
>>
>> early_init_fdt_scan_reserved_mem();
>>
>> --
>> 2.17.1
>>
>
> From 0e5661c6f1ac2d4b08a55d38c6bc224c187af14f Mon Sep 17 00:00:00 2001
> From: Florian Fainelli <f.fainelli@xxxxxxxxx>
> Date: Sat, 27 Oct 2018 12:04:58 +0300
> Subject: [PATCH] arm64: Get rid of __early_init_dt_declare_initrd()
>
> ARM64 is the only architecture that re-defines
> __early_init_dt_declare_initrd() in order for that function to populate
> initrd_start/initrd_end with physical addresses instead of virtual
> addresses. Instead of having an override, just get rid of that
> implementation and perform the virtual to physical conversion of these
> addresses in arm64_memblock_init() where relevant.
>
> Signed-off-by: Florian Fainelli <f.fainelli@xxxxxxxxx>
> Signed-off-by: Mike Rapoport <rppt@xxxxxxxxxxxxx>
> ---
> arch/arm64/include/asm/memory.h | 8 --------
> arch/arm64/mm/init.c | 40 +++++++++++++++++++++++++---------------
> 2 files changed, 25 insertions(+), 23 deletions(-)
>
> diff --git a/arch/arm64/include/asm/memory.h b/arch/arm64/include/asm/memory.h
> index b9644296..dc3ca21 100644
> --- a/arch/arm64/include/asm/memory.h
> +++ b/arch/arm64/include/asm/memory.h
> @@ -168,14 +168,6 @@
> #define IOREMAP_MAX_ORDER (PMD_SHIFT)
> #endif
>
> -#ifdef CONFIG_BLK_DEV_INITRD
> -#define __early_init_dt_declare_initrd(__start, __end) \
> - do { \
> - initrd_start = (__start); \
> - initrd_end = (__end); \
> - } while (0)
> -#endif
> -
> #ifndef __ASSEMBLY__
>
> #include <linux/bitops.h>
> diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
> index 9d9582c..dd665be3 100644
> --- a/arch/arm64/mm/init.c
> +++ b/arch/arm64/mm/init.c
> @@ -61,6 +61,8 @@
> s64 memstart_addr __ro_after_init = -1;
> phys_addr_t arm64_dma_phys_limit __ro_after_init;
>
> +static phys_addr_t phys_initrd_start, phys_initrd_end;
> +
> #ifdef CONFIG_BLK_DEV_INITRD
> static int __init early_initrd(char *p)
> {
> @@ -71,8 +73,8 @@ static int __init early_initrd(char *p)
> if (*endp == ',') {
> size = memparse(endp + 1, NULL);
>
> - initrd_start = start;
> - initrd_end = start + size;
> + phys_initrd_start = start;
> + phys_initrd_end = start + size;
> }
> return 0;
> }
> @@ -363,6 +365,7 @@ static void __init fdt_enforce_memory_region(void)
> void __init arm64_memblock_init(void)
> {
> const s64 linear_region_size = -(s64)PAGE_OFFSET;
> + u64 __maybe_unused base, size;
>
> /* Handle linux,usable-memory-range property */
> fdt_enforce_memory_region();
> @@ -407,14 +410,23 @@ void __init arm64_memblock_init(void)
> memblock_add(__pa_symbol(_text), (u64)(_end - _text));
> }
>
> - if (IS_ENABLED(CONFIG_BLK_DEV_INITRD) && initrd_start) {
> + if (IS_ENABLED(CONFIG_BLK_DEV_INITRD) &&
> + (initrd_start || phys_initrd_start)) {
> /*
> * Add back the memory we just removed if it results in the
> * initrd to become inaccessible via the linear mapping.
> * Otherwise, this is a no-op
> */
> - u64 base = initrd_start & PAGE_MASK;
> - u64 size = PAGE_ALIGN(initrd_end) - base;
> + if (phys_initrd_start) {
> + initrd_start = __phys_to_virt(phys_initrd_start);
> + initrd_end = __phys_to_virt(phys_initrd_end);
> + } else if (initrd_start) {
> + phys_initrd_start = __pa(initrd_start);
> + phys_initrd_end = __pa(initrd_end);
> + }
> +
> + base = phys_initrd_start & PAGE_MASK;
> + size = PAGE_ALIGN(phys_initrd_end - phys_initrd_start);
>
> /*
> * We can only add back the initrd memory if we don't end up
> @@ -433,6 +445,13 @@ void __init arm64_memblock_init(void)
> memblock_remove(base, size); /* clear MEMBLOCK_ flags */
> memblock_add(base, size);
> memblock_reserve(base, size);
> +
> + /*
> + * initrd_below_start_ok can be changed by
> + * __early_init_dt_declare_initrd(), set it back to what
> + * we want here.
> + */
> + initrd_below_start_ok = 0;
> }
> }
>
> @@ -454,19 +473,10 @@ void __init arm64_memblock_init(void)
> }
>
> /*
> - * Register the kernel text, kernel data, initrd, and initial
> + * Register the kernel text, kernel data and initial
> * pagetables with memblock.
> */
> memblock_reserve(__pa_symbol(_text), _end - _text);
> -#ifdef CONFIG_BLK_DEV_INITRD
> - if (initrd_start) {
> - memblock_reserve(initrd_start, initrd_end - initrd_start);
> -
> - /* the generic initrd code expects virtual addresses */
> - initrd_start = __phys_to_virt(initrd_start);
> - initrd_end = __phys_to_virt(initrd_end);
> - }
> -#endif
>
> early_init_fdt_scan_reserved_mem();
>
>


--
Florian