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-rw-r--r--mm/Kconfig3
-rw-r--r--mm/Makefile2
-rw-r--r--mm/memblock.c541
3 files changed, 546 insertions, 0 deletions
diff --git a/mm/Kconfig b/mm/Kconfig
index 527136b22384..f4e516e9c37c 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -128,6 +128,9 @@ config SPARSEMEM_VMEMMAP
pfn_to_page and page_to_pfn operations. This is the most
efficient option when sufficient kernel resources are available.
+config HAVE_MEMBLOCK
+ boolean
+
# eventually, we can have this option just 'select SPARSEMEM'
config MEMORY_HOTPLUG
bool "Allow for memory hot-add"
diff --git a/mm/Makefile b/mm/Makefile
index 8982504bd03b..34b2546a9e37 100644
--- a/mm/Makefile
+++ b/mm/Makefile
@@ -15,6 +15,8 @@ obj-y := bootmem.o filemap.o mempool.o oom_kill.o fadvise.o \
$(mmu-y)
obj-y += init-mm.o
+obj-$(CONFIG_HAVE_MEMBLOCK) += memblock.o
+
obj-$(CONFIG_BOUNCE) += bounce.o
obj-$(CONFIG_SWAP) += page_io.o swap_state.o swapfile.o thrash.o
obj-$(CONFIG_HAS_DMA) += dmapool.o
diff --git a/mm/memblock.c b/mm/memblock.c
new file mode 100644
index 000000000000..3024eb30fc27
--- /dev/null
+++ b/mm/memblock.c
@@ -0,0 +1,541 @@
+/*
+ * Procedures for maintaining information about logical memory blocks.
+ *
+ * Peter Bergner, IBM Corp. June 2001.
+ * Copyright (C) 2001 Peter Bergner.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/bitops.h>
+#include <linux/memblock.h>
+
+#define MEMBLOCK_ALLOC_ANYWHERE 0
+
+struct memblock memblock;
+
+static int memblock_debug;
+
+static int __init early_memblock(char *p)
+{
+ if (p && strstr(p, "debug"))
+ memblock_debug = 1;
+ return 0;
+}
+early_param("memblock", early_memblock);
+
+static void memblock_dump(struct memblock_region *region, char *name)
+{
+ unsigned long long base, size;
+ int i;
+
+ pr_info(" %s.cnt = 0x%lx\n", name, region->cnt);
+
+ for (i = 0; i < region->cnt; i++) {
+ base = region->region[i].base;
+ size = region->region[i].size;
+
+ pr_info(" %s[0x%x]\t0x%016llx - 0x%016llx, 0x%llx bytes\n",
+ name, i, base, base + size - 1, size);
+ }
+}
+
+void memblock_dump_all(void)
+{
+ if (!memblock_debug)
+ return;
+
+ pr_info("MEMBLOCK configuration:\n");
+ pr_info(" rmo_size = 0x%llx\n", (unsigned long long)memblock.rmo_size);
+ pr_info(" memory.size = 0x%llx\n", (unsigned long long)memblock.memory.size);
+
+ memblock_dump(&memblock.memory, "memory");
+ memblock_dump(&memblock.reserved, "reserved");
+}
+
+static unsigned long memblock_addrs_overlap(u64 base1, u64 size1, u64 base2,
+ u64 size2)
+{
+ return ((base1 < (base2 + size2)) && (base2 < (base1 + size1)));
+}
+
+static long memblock_addrs_adjacent(u64 base1, u64 size1, u64 base2, u64 size2)
+{
+ if (base2 == base1 + size1)
+ return 1;
+ else if (base1 == base2 + size2)
+ return -1;
+
+ return 0;
+}
+
+static long memblock_regions_adjacent(struct memblock_region *rgn,
+ unsigned long r1, unsigned long r2)
+{
+ u64 base1 = rgn->region[r1].base;
+ u64 size1 = rgn->region[r1].size;
+ u64 base2 = rgn->region[r2].base;
+ u64 size2 = rgn->region[r2].size;
+
+ return memblock_addrs_adjacent(base1, size1, base2, size2);
+}
+
+static void memblock_remove_region(struct memblock_region *rgn, unsigned long r)
+{
+ unsigned long i;
+
+ for (i = r; i < rgn->cnt - 1; i++) {
+ rgn->region[i].base = rgn->region[i + 1].base;
+ rgn->region[i].size = rgn->region[i + 1].size;
+ }
+ rgn->cnt--;
+}
+
+/* Assumption: base addr of region 1 < base addr of region 2 */
+static void memblock_coalesce_regions(struct memblock_region *rgn,
+ unsigned long r1, unsigned long r2)
+{
+ rgn->region[r1].size += rgn->region[r2].size;
+ memblock_remove_region(rgn, r2);
+}
+
+void __init memblock_init(void)
+{
+ /* Create a dummy zero size MEMBLOCK which will get coalesced away later.
+ * This simplifies the memblock_add() code below...
+ */
+ memblock.memory.region[0].base = 0;
+ memblock.memory.region[0].size = 0;
+ memblock.memory.cnt = 1;
+
+ /* Ditto. */
+ memblock.reserved.region[0].base = 0;
+ memblock.reserved.region[0].size = 0;
+ memblock.reserved.cnt = 1;
+}
+
+void __init memblock_analyze(void)
+{
+ int i;
+
+ memblock.memory.size = 0;
+
+ for (i = 0; i < memblock.memory.cnt; i++)
+ memblock.memory.size += memblock.memory.region[i].size;
+}
+
+static long memblock_add_region(struct memblock_region *rgn, u64 base, u64 size)
+{
+ unsigned long coalesced = 0;
+ long adjacent, i;
+
+ if ((rgn->cnt == 1) && (rgn->region[0].size == 0)) {
+ rgn->region[0].base = base;
+ rgn->region[0].size = size;
+ return 0;
+ }
+
+ /* First try and coalesce this MEMBLOCK with another. */
+ for (i = 0; i < rgn->cnt; i++) {
+ u64 rgnbase = rgn->region[i].base;
+ u64 rgnsize = rgn->region[i].size;
+
+ if ((rgnbase == base) && (rgnsize == size))
+ /* Already have this region, so we're done */
+ return 0;
+
+ adjacent = memblock_addrs_adjacent(base, size, rgnbase, rgnsize);
+ if (adjacent > 0) {
+ rgn->region[i].base -= size;
+ rgn->region[i].size += size;
+ coalesced++;
+ break;
+ } else if (adjacent < 0) {
+ rgn->region[i].size += size;
+ coalesced++;
+ break;
+ }
+ }
+
+ if ((i < rgn->cnt - 1) && memblock_regions_adjacent(rgn, i, i+1)) {
+ memblock_coalesce_regions(rgn, i, i+1);
+ coalesced++;
+ }
+
+ if (coalesced)
+ return coalesced;
+ if (rgn->cnt >= MAX_MEMBLOCK_REGIONS)
+ return -1;
+
+ /* Couldn't coalesce the MEMBLOCK, so add it to the sorted table. */
+ for (i = rgn->cnt - 1; i >= 0; i--) {
+ if (base < rgn->region[i].base) {
+ rgn->region[i+1].base = rgn->region[i].base;
+ rgn->region[i+1].size = rgn->region[i].size;
+ } else {
+ rgn->region[i+1].base = base;
+ rgn->region[i+1].size = size;
+ break;
+ }
+ }
+
+ if (base < rgn->region[0].base) {
+ rgn->region[0].base = base;
+ rgn->region[0].size = size;
+ }
+ rgn->cnt++;
+
+ return 0;
+}
+
+long memblock_add(u64 base, u64 size)
+{
+ struct memblock_region *_rgn = &memblock.memory;
+
+ /* On pSeries LPAR systems, the first MEMBLOCK is our RMO region. */
+ if (base == 0)
+ memblock.rmo_size = size;
+
+ return memblock_add_region(_rgn, base, size);
+
+}
+
+static long __memblock_remove(struct memblock_region *rgn, u64 base, u64 size)
+{
+ u64 rgnbegin, rgnend;
+ u64 end = base + size;
+ int i;
+
+ rgnbegin = rgnend = 0; /* supress gcc warnings */
+
+ /* Find the region where (base, size) belongs to */
+ for (i=0; i < rgn->cnt; i++) {
+ rgnbegin = rgn->region[i].base;
+ rgnend = rgnbegin + rgn->region[i].size;
+
+ if ((rgnbegin <= base) && (end <= rgnend))
+ break;
+ }
+
+ /* Didn't find the region */
+ if (i == rgn->cnt)
+ return -1;
+
+ /* Check to see if we are removing entire region */
+ if ((rgnbegin == base) && (rgnend == end)) {
+ memblock_remove_region(rgn, i);
+ return 0;
+ }
+
+ /* Check to see if region is matching at the front */
+ if (rgnbegin == base) {
+ rgn->region[i].base = end;
+ rgn->region[i].size -= size;
+ return 0;
+ }
+
+ /* Check to see if the region is matching at the end */
+ if (rgnend == end) {
+ rgn->region[i].size -= size;
+ return 0;
+ }
+
+ /*
+ * We need to split the entry - adjust the current one to the
+ * beginging of the hole and add the region after hole.
+ */
+ rgn->region[i].size = base - rgn->region[i].base;
+ return memblock_add_region(rgn, end, rgnend - end);
+}
+
+long memblock_remove(u64 base, u64 size)
+{
+ return __memblock_remove(&memblock.memory, base, size);
+}
+
+long __init memblock_free(u64 base, u64 size)
+{
+ return __memblock_remove(&memblock.reserved, base, size);
+}
+
+long __init memblock_reserve(u64 base, u64 size)
+{
+ struct memblock_region *_rgn = &memblock.reserved;
+
+ BUG_ON(0 == size);
+
+ return memblock_add_region(_rgn, base, size);
+}
+
+long memblock_overlaps_region(struct memblock_region *rgn, u64 base, u64 size)
+{
+ unsigned long i;
+
+ for (i = 0; i < rgn->cnt; i++) {
+ u64 rgnbase = rgn->region[i].base;
+ u64 rgnsize = rgn->region[i].size;
+ if (memblock_addrs_overlap(base, size, rgnbase, rgnsize))
+ break;
+ }
+
+ return (i < rgn->cnt) ? i : -1;
+}
+
+static u64 memblock_align_down(u64 addr, u64 size)
+{
+ return addr & ~(size - 1);
+}
+
+static u64 memblock_align_up(u64 addr, u64 size)
+{
+ return (addr + (size - 1)) & ~(size - 1);
+}
+
+static u64 __init memblock_alloc_nid_unreserved(u64 start, u64 end,
+ u64 size, u64 align)
+{
+ u64 base, res_base;
+ long j;
+
+ base = memblock_align_down((end - size), align);
+ while (start <= base) {
+ j = memblock_overlaps_region(&memblock.reserved, base, size);
+ if (j < 0) {
+ /* this area isn't reserved, take it */
+ if (memblock_add_region(&memblock.reserved, base, size) < 0)
+ base = ~(u64)0;
+ return base;
+ }
+ res_base = memblock.reserved.region[j].base;
+ if (res_base < size)
+ break;
+ base = memblock_align_down(res_base - size, align);
+ }
+
+ return ~(u64)0;
+}
+
+static u64 __init memblock_alloc_nid_region(struct memblock_property *mp,
+ u64 (*nid_range)(u64, u64, int *),
+ u64 size, u64 align, int nid)
+{
+ u64 start, end;
+
+ start = mp->base;
+ end = start + mp->size;
+
+ start = memblock_align_up(start, align);
+ while (start < end) {
+ u64 this_end;
+ int this_nid;
+
+ this_end = nid_range(start, end, &this_nid);
+ if (this_nid == nid) {
+ u64 ret = memblock_alloc_nid_unreserved(start, this_end,
+ size, align);
+ if (ret != ~(u64)0)
+ return ret;
+ }
+ start = this_end;
+ }
+
+ return ~(u64)0;
+}
+
+u64 __init memblock_alloc_nid(u64 size, u64 align, int nid,
+ u64 (*nid_range)(u64 start, u64 end, int *nid))
+{
+ struct memblock_region *mem = &memblock.memory;
+ int i;
+
+ BUG_ON(0 == size);
+
+ size = memblock_align_up(size, align);
+
+ for (i = 0; i < mem->cnt; i++) {
+ u64 ret = memblock_alloc_nid_region(&mem->region[i],
+ nid_range,
+ size, align, nid);
+ if (ret != ~(u64)0)
+ return ret;
+ }
+
+ return memblock_alloc(size, align);
+}
+
+u64 __init memblock_alloc(u64 size, u64 align)
+{
+ return memblock_alloc_base(size, align, MEMBLOCK_ALLOC_ANYWHERE);
+}
+
+u64 __init memblock_alloc_base(u64 size, u64 align, u64 max_addr)
+{
+ u64 alloc;
+
+ alloc = __memblock_alloc_base(size, align, max_addr);
+
+ if (alloc == 0)
+ panic("ERROR: Failed to allocate 0x%llx bytes below 0x%llx.\n",
+ (unsigned long long) size, (unsigned long long) max_addr);
+
+ return alloc;
+}
+
+u64 __init __memblock_alloc_base(u64 size, u64 align, u64 max_addr)
+{
+ long i, j;
+ u64 base = 0;
+ u64 res_base;
+
+ BUG_ON(0 == size);
+
+ size = memblock_align_up(size, align);
+
+ /* On some platforms, make sure we allocate lowmem */
+ /* Note that MEMBLOCK_REAL_LIMIT may be MEMBLOCK_ALLOC_ANYWHERE */
+ if (max_addr == MEMBLOCK_ALLOC_ANYWHERE)
+ max_addr = MEMBLOCK_REAL_LIMIT;
+
+ for (i = memblock.memory.cnt - 1; i >= 0; i--) {
+ u64 memblockbase = memblock.memory.region[i].base;
+ u64 memblocksize = memblock.memory.region[i].size;
+
+ if (memblocksize < size)
+ continue;
+ if (max_addr == MEMBLOCK_ALLOC_ANYWHERE)
+ base = memblock_align_down(memblockbase + memblocksize - size, align);
+ else if (memblockbase < max_addr) {
+ base = min(memblockbase + memblocksize, max_addr);
+ base = memblock_align_down(base - size, align);
+ } else
+ continue;
+
+ while (base && memblockbase <= base) {
+ j = memblock_overlaps_region(&memblock.reserved, base, size);
+ if (j < 0) {
+ /* this area isn't reserved, take it */
+ if (memblock_add_region(&memblock.reserved, base, size) < 0)
+ return 0;
+ return base;
+ }
+ res_base = memblock.reserved.region[j].base;
+ if (res_base < size)
+ break;
+ base = memblock_align_down(res_base - size, align);
+ }
+ }
+ return 0;
+}
+
+/* You must call memblock_analyze() before this. */
+u64 __init memblock_phys_mem_size(void)
+{
+ return memblock.memory.size;
+}
+
+u64 memblock_end_of_DRAM(void)
+{
+ int idx = memblock.memory.cnt - 1;
+
+ return (memblock.memory.region[idx].base + memblock.memory.region[idx].size);
+}
+
+/* You must call memblock_analyze() after this. */
+void __init memblock_enforce_memory_limit(u64 memory_limit)
+{
+ unsigned long i;
+ u64 limit;
+ struct memblock_property *p;
+
+ if (!memory_limit)
+ return;
+
+ /* Truncate the memblock regions to satisfy the memory limit. */
+ limit = memory_limit;
+ for (i = 0; i < memblock.memory.cnt; i++) {
+ if (limit > memblock.memory.region[i].size) {
+ limit -= memblock.memory.region[i].size;
+ continue;
+ }
+
+ memblock.memory.region[i].size = limit;
+ memblock.memory.cnt = i + 1;
+ break;
+ }
+
+ if (memblock.memory.region[0].size < memblock.rmo_size)
+ memblock.rmo_size = memblock.memory.region[0].size;
+
+ memory_limit = memblock_end_of_DRAM();
+
+ /* And truncate any reserves above the limit also. */
+ for (i = 0; i < memblock.reserved.cnt; i++) {
+ p = &memblock.reserved.region[i];
+
+ if (p->base > memory_limit)
+ p->size = 0;
+ else if ((p->base + p->size) > memory_limit)
+ p->size = memory_limit - p->base;
+
+ if (p->size == 0) {
+ memblock_remove_region(&memblock.reserved, i);
+ i--;
+ }
+ }
+}
+
+int __init memblock_is_reserved(u64 addr)
+{
+ int i;
+
+ for (i = 0; i < memblock.reserved.cnt; i++) {
+ u64 upper = memblock.reserved.region[i].base +
+ memblock.reserved.region[i].size - 1;
+ if ((addr >= memblock.reserved.region[i].base) && (addr <= upper))
+ return 1;
+ }
+ return 0;
+}
+
+int memblock_is_region_reserved(u64 base, u64 size)
+{
+ return memblock_overlaps_region(&memblock.reserved, base, size);
+}
+
+/*
+ * Given a <base, len>, find which memory regions belong to this range.
+ * Adjust the request and return a contiguous chunk.
+ */
+int memblock_find(struct memblock_property *res)
+{
+ int i;
+ u64 rstart, rend;
+
+ rstart = res->base;
+ rend = rstart + res->size - 1;
+
+ for (i = 0; i < memblock.memory.cnt; i++) {
+ u64 start = memblock.memory.region[i].base;
+ u64 end = start + memblock.memory.region[i].size - 1;
+
+ if (start > rend)
+ return -1;
+
+ if ((end >= rstart) && (start < rend)) {
+ /* adjust the request */
+ if (rstart < start)
+ rstart = start;
+ if (rend > end)
+ rend = end;
+ res->base = rstart;
+ res->size = rend - rstart + 1;
+ return 0;
+ }
+ }
+ return -1;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-21 06:15:21 +0000