[PATCH v2] memblock: make memblock_find_in_range method private

From: Mike Rapoport
Date: Mon Aug 02 2021 - 02:38:01 EST

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) {
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);
diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c
index ff0f9e838916..3d9efee0f43c 100644
--- a/arch/s390/kernel/setup.c
+++ b/arch/s390/kernel/setup.c
@@ -626,8 +626,9 @@ static void __init reserve_crashkernel(void)
return;
}
low = crash_base ?: low;
- crash_base = memblock_find_in_range(low, high, crash_size,
- KEXEC_CRASH_MEM_ALIGN);
+ crash_base = memblock_phys_alloc_range(crash_size,
+ KEXEC_CRASH_MEM_ALIGN,
+ low, high);
}

if (!crash_base) {
@@ -636,14 +637,15 @@ static void __init reserve_crashkernel(void)
return;
}

- if (register_memory_notifier(&kdump_mem_nb))
+ if (register_memory_notifier(&kdump_mem_nb)) {
+ memblock_free(crash_base, crash_size);
return;
+ }

if (!OLDMEM_BASE && MACHINE_IS_VM)
diag10_range(PFN_DOWN(crash_base), PFN_DOWN(crash_size));
crashk_res.start = crash_base;
crashk_res.end = crash_base + crash_size - 1;
- memblock_remove(crash_base, crash_size);
pr_info("Reserving %lluMB of memory at %lluMB "
"for crashkernel (System RAM: %luMB)\n",
crash_size >> 20, crash_base >> 20,
diff --git a/arch/x86/kernel/aperture_64.c b/arch/x86/kernel/aperture_64.c
index 294ed4392a0e..10562885f5fc 100644
--- a/arch/x86/kernel/aperture_64.c
+++ b/arch/x86/kernel/aperture_64.c
@@ -109,14 +109,13 @@ static u32 __init allocate_aperture(void)
* memory. Unfortunately we cannot move it up because that would
* make the IOMMU useless.
*/
- addr = memblock_find_in_range(GART_MIN_ADDR, GART_MAX_ADDR,
- aper_size, aper_size);
+ addr = memblock_phys_alloc_range(aper_size, aper_size,
+ GART_MIN_ADDR, GART_MAX_ADDR);
if (!addr) {
pr_err("Cannot allocate aperture memory hole [mem %#010lx-%#010lx] (%uKB)\n",
addr, addr + aper_size - 1, aper_size >> 10);
return 0;
}
- memblock_reserve(addr, aper_size);
pr_info("Mapping aperture over RAM [mem %#010lx-%#010lx] (%uKB)\n",
addr, addr + aper_size - 1, aper_size >> 10);
register_nosave_region(addr >> PAGE_SHIFT,
diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c
index 75ef19aa8903..1152a29ce109 100644
--- a/arch/x86/mm/init.c
+++ b/arch/x86/mm/init.c
@@ -26,6 +26,7 @@
#include <asm/pti.h>
#include <asm/text-patching.h>
#include <asm/memtype.h>
+#include <xen/xen.h>

/*
* We need to define the tracepoints somewhere, and tlb.c
@@ -127,14 +128,12 @@ __ref void *alloc_low_pages(unsigned int num)
unsigned long ret = 0;

if (min_pfn_mapped < max_pfn_mapped) {
- ret = memblock_find_in_range(
+ ret = memblock_phys_alloc_range(
+ PAGE_SIZE * num, PAGE_SIZE,
min_pfn_mapped << PAGE_SHIFT,
- max_pfn_mapped << PAGE_SHIFT,
- PAGE_SIZE * num , PAGE_SIZE);
+ max_pfn_mapped << PAGE_SHIFT);
}
- if (ret)
- memblock_reserve(ret, PAGE_SIZE * num);
- else if (can_use_brk_pgt)
+ if (!ret && can_use_brk_pgt)
ret = __pa(extend_brk(PAGE_SIZE * num, PAGE_SIZE));

if (!ret)
@@ -610,9 +609,15 @@ static void __init memory_map_top_down(unsigned long map_start,
unsigned long addr;
unsigned long mapped_ram_size = 0;

+ real_end = ALIGN_DOWN(map_end, PMD_SIZE);
+
/* xen has big range in reserved near end of ram, skip it at first.*/
- addr = memblock_find_in_range(map_start, map_end, PMD_SIZE, PMD_SIZE);
- real_end = addr + PMD_SIZE;
+ if (xen_domain()) {
+ addr = memblock_phys_alloc_range(PMD_SIZE, PMD_SIZE,
+ map_start, map_end);
+ memblock_free(addr, PMD_SIZE);
+ real_end = addr + PMD_SIZE;
+ }

/* step_size need to be small so pgt_buf from BRK could cover it */
step_size = PMD_SIZE;
diff --git a/arch/x86/mm/numa.c b/arch/x86/mm/numa.c
index e94da744386f..a1b5c71099e6 100644
--- a/arch/x86/mm/numa.c
+++ b/arch/x86/mm/numa.c
@@ -376,15 +376,14 @@ static int __init numa_alloc_distance(void)
cnt++;
size = cnt * cnt * sizeof(numa_distance[0]);

- phys = memblock_find_in_range(0, PFN_PHYS(max_pfn_mapped),
- size, PAGE_SIZE);
+ phys = memblock_phys_alloc_range(size, PAGE_SIZE, 0,
+ PFN_PHYS(max_pfn_mapped));
if (!phys) {
pr_warn("Warning: can't allocate distance table!\n");
/* don't retry until explicitly reset */
numa_distance = (void *)1LU;
return -ENOMEM;
}
- memblock_reserve(phys, size);

numa_distance = __va(phys);
numa_distance_cnt = cnt;
diff --git a/arch/x86/mm/numa_emulation.c b/arch/x86/mm/numa_emulation.c
index 87d77cc52f86..737491b13728 100644
--- a/arch/x86/mm/numa_emulation.c
+++ b/arch/x86/mm/numa_emulation.c
@@ -447,13 +447,12 @@ void __init numa_emulation(struct numa_meminfo *numa_meminfo, int numa_dist_cnt)
if (numa_dist_cnt) {
u64 phys;

- phys = memblock_find_in_range(0, PFN_PHYS(max_pfn_mapped),
- phys_size, PAGE_SIZE);
+ phys = memblock_phys_alloc_range(phys_size, PAGE_SIZE, 0,
+ PFN_PHYS(max_pfn_mapped));
if (!phys) {
pr_warn("NUMA: Warning: can't allocate copy of distance table, disabling emulation\n");
goto no_emu;
}
- memblock_reserve(phys, phys_size);
phys_dist = __va(phys);

for (i = 0; i < numa_dist_cnt; i++)
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
diff --git a/drivers/acpi/tables.c b/drivers/acpi/tables.c
index a37a1532a575..f9383736fa0f 100644
--- a/drivers/acpi/tables.c
+++ b/drivers/acpi/tables.c
@@ -583,8 +583,8 @@ void __init acpi_table_upgrade(void)
}

acpi_tables_addr =
- memblock_find_in_range(0, ACPI_TABLE_UPGRADE_MAX_PHYS,
- all_tables_size, PAGE_SIZE);
+ memblock_phys_alloc_range(all_tables_size, PAGE_SIZE,
+ 0, ACPI_TABLE_UPGRADE_MAX_PHYS);
if (!acpi_tables_addr) {
WARN_ON(1);
return;
@@ -599,7 +599,6 @@ void __init acpi_table_upgrade(void)
* Both memblock_reserve and e820__range_add (via arch_reserve_mem_area)
* works fine.
*/
- memblock_reserve(acpi_tables_addr, all_tables_size);
arch_reserve_mem_area(acpi_tables_addr, all_tables_size);

/*
diff --git a/drivers/base/arch_numa.c b/drivers/base/arch_numa.c
index 4cc4e117727d..46c503486e96 100644
--- a/drivers/base/arch_numa.c
+++ b/drivers/base/arch_numa.c
@@ -279,13 +279,10 @@ static int __init numa_alloc_distance(void)
int i, j;

size = nr_node_ids * nr_node_ids * sizeof(numa_distance[0]);
- phys = memblock_find_in_range(0, PFN_PHYS(max_pfn),
- size, PAGE_SIZE);
+ phys = memblock_phys_alloc_range(size, PAGE_SIZE, 0, PFN_PHYS(max_pfn));
if (WARN_ON(!phys))
return -ENOMEM;

- memblock_reserve(phys, size);
-
numa_distance = __va(phys);
numa_distance_cnt = nr_node_ids;

diff --git a/drivers/of/of_reserved_mem.c b/drivers/of/of_reserved_mem.c
index fd3964d24224..59c1390cdf42 100644
--- a/drivers/of/of_reserved_mem.c
+++ b/drivers/of/of_reserved_mem.c
@@ -33,18 +33,22 @@ static int __init early_init_dt_alloc_reserved_memory_arch(phys_addr_t size,
phys_addr_t *res_base)
{
phys_addr_t base;
+ int err = 0;

end = !end ? MEMBLOCK_ALLOC_ANYWHERE : end;
align = !align ? SMP_CACHE_BYTES : align;
- base = memblock_find_in_range(start, end, size, align);
+ base = memblock_phys_alloc_range(size, align, start, end);
if (!base)
return -ENOMEM;

*res_base = base;
- if (nomap)
- return memblock_mark_nomap(base, size);
+ if (nomap) {
+ err = memblock_mark_nomap(base, size);
+ if (err)
+ memblock_free(base, size);
+ }

- return memblock_reserve(base, size);
+ return err;
}

/*
diff --git a/include/linux/memblock.h b/include/linux/memblock.h
index 4a53c3ca86bd..b066024c62e3 100644
--- a/include/linux/memblock.h
+++ b/include/linux/memblock.h
@@ -99,8 +99,6 @@ void memblock_discard(void);
static inline void memblock_discard(void) {}
#endif

-phys_addr_t memblock_find_in_range(phys_addr_t start, phys_addr_t end,
- phys_addr_t size, phys_addr_t align);
void memblock_allow_resize(void);
int memblock_add_node(phys_addr_t base, phys_addr_t size, int nid);
int memblock_add(phys_addr_t base, phys_addr_t size);
diff --git a/mm/memblock.c b/mm/memblock.c
index de7b553baa50..28a813d9e955 100644
--- a/mm/memblock.c
+++ b/mm/memblock.c
@@ -315,7 +315,7 @@ static phys_addr_t __init_memblock memblock_find_in_range_node(phys_addr_t size,
* Return:
* Found address on success, 0 on failure.
*/
-phys_addr_t __init_memblock memblock_find_in_range(phys_addr_t start,
+static phys_addr_t __init_memblock memblock_find_in_range(phys_addr_t start,
phys_addr_t end, phys_addr_t size,
phys_addr_t align)
{

base-commit: ff1176468d368232b684f75e82563369208bc371
--
2.28.0