Re: [PATCH v2] memblock: make memblock_find_in_range method private

Nick Kossifidis
2021-08-07T23:40:10Z

Στις 2021-08-02 09:37, Mike Rapoport έγραψε:
> From: Mike Rapoport <rppt@linux.ibm.com>
>
> There are a lot of uses of memblock_find_in_range() along with
> memblock_reserve() from the times memblock allocation APIs did not
> exist.
>
> memblock_find_in_range() is the very core of memblock allocations, so
> any
> future changes to its internal behaviour would mandate updates of all
> the
> users outside memblock.
>
> Replace the calls to memblock_find_in_range() with an equivalent calls
> to
> memblock_phys_alloc() and memblock_phys_alloc_range() and make
> memblock_find_in_range() private method of memblock.
>
> This simplifies the callers, ensures that (unlikely) errors in
> memblock_reserve() are handled and improves maintainability of
> memblock_find_in_range().
>
> Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
> ---
> v2: don't change error message in arm::reserve_crashkernel(), per
> Russell
> v1: https://lore.kernel.org/lkml/20210730104039.7047-1-rppt@kernel.org
>
> arch/arm/kernel/setup.c | 18 +++++--------
> arch/arm64/kvm/hyp/reserved_mem.c | 9 +++----
> arch/arm64/mm/init.c | 36 ++++++++-----------------
> arch/mips/kernel/setup.c | 14 +++++-----
> arch/riscv/mm/init.c | 44 ++++++++++---------------------
> arch/s390/kernel/setup.c | 10 ++++---
> arch/x86/kernel/aperture_64.c | 5 ++--
> arch/x86/mm/init.c | 21 +++++++++------
> arch/x86/mm/numa.c | 5 ++--
> arch/x86/mm/numa_emulation.c | 5 ++--
> arch/x86/realmode/init.c | 2 +-
> drivers/acpi/tables.c | 5 ++--
> drivers/base/arch_numa.c | 5 +---
> drivers/of/of_reserved_mem.c | 12 ++++++---
> include/linux/memblock.h | 2 --
> mm/memblock.c | 2 +-
> 16 files changed, 78 insertions(+), 117 deletions(-)
>
> diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c
> index f97eb2371672..67f5421b2af7 100644
> --- a/arch/arm/kernel/setup.c
> +++ b/arch/arm/kernel/setup.c
> @@ -1012,31 +1012,25 @@ static void __init reserve_crashkernel(void)
> unsigned long long lowmem_max = __pa(high_memory - 1) + 1;
> if (crash_max > lowmem_max)
> crash_max = lowmem_max;
> - crash_base = memblock_find_in_range(CRASH_ALIGN, crash_max,
> - crash_size, CRASH_ALIGN);
> +
> + crash_base = memblock_phys_alloc_range(crash_size, CRASH_ALIGN,
> + CRASH_ALIGN, crash_max);
> if (!crash_base) {
> pr_err("crashkernel reservation failed - No suitable area
> found.\n");
> return;
> }
> } else {
> + unsigned long long crash_max = crash_base + crash_size;
> unsigned long long start;
>
> - start = memblock_find_in_range(crash_base,
> - crash_base + crash_size,
> - crash_size, SECTION_SIZE);
> + start = memblock_phys_alloc_range(crash_size, SECTION_SIZE,
> + crash_base, crash_max);
> if (start != crash_base) {
> pr_err("crashkernel reservation failed - memory is in use.\n");
> return;
> }
> }
>
> - ret = memblock_reserve(crash_base, crash_size);
> - if (ret < 0) {
> - pr_warn("crashkernel reservation failed - memory is in use
> (0x%lx)\n",
> - (unsigned long)crash_base);
> - return;
> - }
> -
> pr_info("Reserving %ldMB of memory at %ldMB for crashkernel (System
> RAM: %ldMB)\n",
> (unsigned long)(crash_size >> 20),
> (unsigned long)(crash_base >> 20),
> diff --git a/arch/arm64/kvm/hyp/reserved_mem.c
> b/arch/arm64/kvm/hyp/reserved_mem.c
> index d654921dd09b..578670e3f608 100644
> --- a/arch/arm64/kvm/hyp/reserved_mem.c
> +++ b/arch/arm64/kvm/hyp/reserved_mem.c
> @@ -92,12 +92,10 @@ void __init kvm_hyp_reserve(void)
> * this is unmapped from the host stage-2, and fallback to PAGE_SIZE.
> */
> hyp_mem_size = hyp_mem_pages << PAGE_SHIFT;
> - hyp_mem_base = memblock_find_in_range(0, memblock_end_of_DRAM(),
> - ALIGN(hyp_mem_size, PMD_SIZE),
> - PMD_SIZE);
> + hyp_mem_base = memblock_phys_alloc(ALIGN(hyp_mem_size, PMD_SIZE),
> + PMD_SIZE);
> if (!hyp_mem_base)
> - hyp_mem_base = memblock_find_in_range(0, memblock_end_of_DRAM(),
> - hyp_mem_size, PAGE_SIZE);
> + hyp_mem_base = memblock_phys_alloc(hyp_mem_size, PAGE_SIZE);
> else
> hyp_mem_size = ALIGN(hyp_mem_size, PMD_SIZE);
>
> @@ -105,7 +103,6 @@ void __init kvm_hyp_reserve(void)
> kvm_err("Failed to reserve hyp memory\n");
> return;
> }
> - memblock_reserve(hyp_mem_base, hyp_mem_size);
>
> kvm_info("Reserved %lld MiB at 0x%llx\n", hyp_mem_size >> 20,
> hyp_mem_base);
> diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
> index 8490ed2917ff..d566478a06dd 100644
> --- a/arch/arm64/mm/init.c
> +++ b/arch/arm64/mm/init.c
> @@ -74,6 +74,7 @@ phys_addr_t arm64_dma_phys_limit __ro_after_init;
> static void __init reserve_crashkernel(void)
> {
> unsigned long long crash_base, crash_size;
> + unsigned long crash_max = arm64_dma_phys_limit;
> int ret;
>
> ret = parse_crashkernel(boot_command_line, memblock_phys_mem_size(),
> @@ -84,33 +85,18 @@ static void __init reserve_crashkernel(void)
>
> crash_size = PAGE_ALIGN(crash_size);
>
> - if (crash_base == 0) {
> - /* Current arm64 boot protocol requires 2MB alignment */
> - crash_base = memblock_find_in_range(0, arm64_dma_phys_limit,
> - crash_size, SZ_2M);
> - if (crash_base == 0) {
> - pr_warn("cannot allocate crashkernel (size:0x%llx)\n",
> - crash_size);
> - return;
> - }
> - } else {
> - /* User specifies base address explicitly. */
> - if (!memblock_is_region_memory(crash_base, crash_size)) {
> - pr_warn("cannot reserve crashkernel: region is not memory\n");
> - return;
> - }
> + /* User specifies base address explicitly. */
> + if (crash_base)
> + crash_max = crash_base + crash_size;
>
> - if (memblock_is_region_reserved(crash_base, crash_size)) {
> - pr_warn("cannot reserve crashkernel: region overlaps reserved
> memory\n");
> - return;
> - }
> -
> - if (!IS_ALIGNED(crash_base, SZ_2M)) {
> - pr_warn("cannot reserve crashkernel: base address is not 2MB
> aligned\n");
> - return;
> - }
> + /* Current arm64 boot protocol requires 2MB alignment */
> + crash_base = memblock_phys_alloc_range(crash_size, SZ_2M,
> + crash_base, crash_max);
> + if (!crash_base) {
> + pr_warn("cannot allocate crashkernel (size:0x%llx)\n",
> + crash_size);
> + return;
> }
> - memblock_reserve(crash_base, crash_size);
>
> pr_info("crashkernel reserved: 0x%016llx - 0x%016llx (%lld MB)\n",
> crash_base, crash_base + crash_size, crash_size >> 20);
> diff --git a/arch/mips/kernel/setup.c b/arch/mips/kernel/setup.c
> index 23a140327a0b..f979adfd4fc2 100644
> --- a/arch/mips/kernel/setup.c
> +++ b/arch/mips/kernel/setup.c
> @@ -452,8 +452,9 @@ static void __init mips_parse_crashkernel(void)
> return;
>
> if (crash_base <= 0) {
> - crash_base = memblock_find_in_range(CRASH_ALIGN, CRASH_ADDR_MAX,
> - crash_size, CRASH_ALIGN);
> + crash_base = memblock_phys_alloc_range(crash_size, CRASH_ALIGN,
> + CRASH_ALIGN,
> + CRASH_ADDR_MAX);
> if (!crash_base) {
> pr_warn("crashkernel reservation failed - No suitable area
> found.\n");
> return;
> @@ -461,8 +462,9 @@ static void __init mips_parse_crashkernel(void)
> } else {
> unsigned long long start;
>
> - start = memblock_find_in_range(crash_base, crash_base + crash_size,
> - crash_size, 1);
> + start = memblock_phys_alloc_range(crash_size, 1,
> + crash_base,
> + crash_base + crash_size);
> if (start != crash_base) {
> pr_warn("Invalid memory region reserved for crash kernel\n");
> return;
> @@ -656,10 +658,6 @@ static void __init arch_mem_init(char **cmdline_p)
> mips_reserve_vmcore();
>
> mips_parse_crashkernel();
> -#ifdef CONFIG_KEXEC
> - if (crashk_res.start != crashk_res.end)
> - memblock_reserve(crashk_res.start, resource_size(&crashk_res));
> -#endif
> device_tree_init();
>
> /*
> diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
> index a14bf3910eec..88649337c568 100644
> --- a/arch/riscv/mm/init.c
> +++ b/arch/riscv/mm/init.c
> @@ -812,38 +812,22 @@ static void __init reserve_crashkernel(void)
>
> crash_size = PAGE_ALIGN(crash_size);
>
> - if (crash_base == 0) {
> - /*
> - * Current riscv boot protocol requires 2MB alignment for
> - * RV64 and 4MB alignment for RV32 (hugepage size)
> - */
> - crash_base = memblock_find_in_range(search_start, search_end,
> - crash_size, PMD_SIZE);
> -
> - if (crash_base == 0) {
> - pr_warn("crashkernel: couldn't allocate %lldKB\n",
> - crash_size >> 10);
> - return;
> - }
> - } else {
> - /* User specifies base address explicitly. */
> - if (!memblock_is_region_memory(crash_base, crash_size)) {
> - pr_warn("crashkernel: requested region is not memory\n");
> - return;
> - }
> -
> - if (memblock_is_region_reserved(crash_base, crash_size)) {
> - pr_warn("crashkernel: requested region is reserved\n");
> - return;
> - }
> -
> + if (crash_base) {
> + search_start = crash_base;
> + search_end = crash_base + crash_size;
> + }
>
> - if (!IS_ALIGNED(crash_base, PMD_SIZE)) {
> - pr_warn("crashkernel: requested region is misaligned\n");
> - return;
> - }
> + /*
> + * Current riscv boot protocol requires 2MB alignment for
> + * RV64 and 4MB alignment for RV32 (hugepage size)
> + */
> + crash_base = memblock_phys_alloc_range(crash_size, PMD_SIZE,
> + search_start, search_end);
> + if (crash_base == 0) {
> + pr_warn("crashkernel: couldn't allocate %lldKB\n",
> + crash_size >> 10);
> + return;
> }
> - memblock_reserve(crash_base, crash_size);
>
> pr_info("crashkernel: reserved 0x%016llx - 0x%016llx (%lld MB)\n",
> crash_base, crash_base + crash_size, crash_size >> 20);

For the riscv part:

Acked-by: Nick Kossifidis <mick@ics.forth.gr>