Hi Rob, On Mon, Aug 02, 2021 at 08:55:57AM -0600, Rob Herring wrote: > On Mon, Aug 2, 2021 at 12:37 AM Mike Rapoport <rppt@xxxxxxxxxx> wrote: > > > > From: Mike Rapoport <rppt@xxxxxxxxxxxxx> > > > > 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@xxxxxxxxxxxxx> > > --- > > v2: don't change error message in arm::reserve_crashkernel(), per Russell > > v1: https://lore.kernel.org/lkml/20210730104039.7047-1-rppt@xxxxxxxxxx > > > > 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) { > > If this is true and start is non-zero, then you need an > memblock_free(). However, since the range is equal to the size, then > that can never happen and just checking !start is sufficient. Agree. Will update. > > 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; > > It all works out to the same size, but it doesn't make sense that > crash_base and crash_size are long long and crash_max is long. Indeed, thanks. > > 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; > > We've lost the alignment check. > > Perhaps memblock_phys_alloc_range() should check that the start > matches the alignment. That would simplify the return handling as it > seems NULL is not the only error case. We only lost pr_warn() about the alignment check. When crash_base != 0, we are trying to allocate the exact [base, base + size) region aligned at 2M. If it is free we get the address, if not we get 0. > > - } > > + /* 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/x86/realmode/init.c b/arch/x86/realmode/init.c > > index 6534c92d0f83..31b5856010cb 100644 > > --- a/arch/x86/realmode/init.c > > +++ b/arch/x86/realmode/init.c > > @@ -28,7 +28,7 @@ void __init reserve_real_mode(void) > > WARN_ON(slab_is_available()); > > > > /* Has to be under 1M so we can execute real-mode AP code. */ > > - mem = memblock_find_in_range(0, 1<<20, size, PAGE_SIZE); > > + mem = memblock_phys_alloc_range(size, PAGE_SIZE, 0, 1<<20); > > if (!mem) > > pr_info("No sub-1M memory is available for the trampoline\n"); > > else > > Don't you need to drop the memblock_reserve() after this? Nope, it reserves the entire first 1M, which is more than we allocated here. The call to memblock_reserve() in memblock_phys_alloc_range() will be redundant here, but IMHO it's clearer this way. -- Sincerely yours, Mike.
