1 files changed, 509 insertions, 0 deletions

diff --git a/lib/lmb.c b/lib/lmb.c
new file mode 100644
index 000000000000..83287d3869a3
--- /dev/null
+++ b/lib/lmb.c
@@ -0,0 +1,509 @@
+/*
+ * 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/lmb.h>
+
+#define LMB_ALLOC_ANYWHERE      0
+
+struct lmb lmb;
+
+void lmb_dump_all(void)
+{
+#ifdef DEBUG
+        unsigned long i;
+
+        pr_debug("lmb_dump_all:\n");
+        pr_debug("    memory.cnt                  = 0x%lx\n", lmb.memory.cnt);
+        pr_debug("    memory.size                 = 0x%llx\n",
+            (unsigned long long)lmb.memory.size);
+        for (i=0; i < lmb.memory.cnt ;i++) {
+                pr_debug("    memory.region[0x%x].base       = 0x%llx\n",
+                    i, (unsigned long long)lmb.memory.region[i].base);
+                pr_debug("                    .size     = 0x%llx\n",
+                    (unsigned long long)lmb.memory.region[i].size);
+        }
+
+        pr_debug("    reserved.cnt        = 0x%lx\n", lmb.reserved.cnt);
+        pr_debug("    reserved.size       = 0x%lx\n", lmb.reserved.size);
+        for (i=0; i < lmb.reserved.cnt ;i++) {
+                pr_debug("    reserved.region[0x%x].base       = 0x%llx\n",
+                    i, (unsigned long long)lmb.reserved.region[i].base);
+                pr_debug("                    .size     = 0x%llx\n",
+                    (unsigned long long)lmb.reserved.region[i].size);
+        }
+#endif /* DEBUG */
+}
+
+static unsigned long lmb_addrs_overlap(u64 base1, u64 size1, u64 base2,
+                                        u64 size2)
+{
+        return ((base1 < (base2 + size2)) && (base2 < (base1 + size1)));
+}
+
+static long lmb_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 lmb_regions_adjacent(struct lmb_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 lmb_addrs_adjacent(base1, size1, base2, size2);
+}
+
+static void lmb_remove_region(struct lmb_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 lmb_coalesce_regions(struct lmb_region *rgn,
+                unsigned long r1, unsigned long r2)
+{
+        rgn->region[r1].size += rgn->region[r2].size;
+        lmb_remove_region(rgn, r2);
+}
+
+void __init lmb_init(void)
+{
+        /* Create a dummy zero size LMB which will get coalesced away later.
+         * This simplifies the lmb_add() code below...
+         */
+        lmb.memory.region[0].base = 0;
+        lmb.memory.region[0].size = 0;
+        lmb.memory.cnt = 1;
+
+        /* Ditto. */
+        lmb.reserved.region[0].base = 0;
+        lmb.reserved.region[0].size = 0;
+        lmb.reserved.cnt = 1;
+}
+
+void __init lmb_analyze(void)
+{
+        int i;
+
+        lmb.memory.size = 0;
+
+        for (i = 0; i < lmb.memory.cnt; i++)
+                lmb.memory.size += lmb.memory.region[i].size;
+}
+
+static long lmb_add_region(struct lmb_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 LMB 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 = lmb_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) && lmb_regions_adjacent(rgn, i, i+1)) {
+                lmb_coalesce_regions(rgn, i, i+1);
+                coalesced++;
+        }
+
+        if (coalesced)
+                return coalesced;
+        if (rgn->cnt >= MAX_LMB_REGIONS)
+                return -1;
+
+        /* Couldn't coalesce the LMB, 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 lmb_add(u64 base, u64 size)
+{
+        struct lmb_region *_rgn = &lmb.memory;
+
+        /* On pSeries LPAR systems, the first LMB is our RMO region. */
+        if (base == 0)
+                lmb.rmo_size = size;
+
+        return lmb_add_region(_rgn, base, size);
+
+}
+
+long lmb_remove(u64 base, u64 size)
+{
+        struct lmb_region *rgn = &(lmb.memory);
+        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)) {
+                lmb_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 lmb_add_region(rgn, end, rgnend - end);
+}
+
+long __init lmb_reserve(u64 base, u64 size)
+{
+        struct lmb_region *_rgn = &lmb.reserved;
+
+        BUG_ON(0 == size);
+
+        return lmb_add_region(_rgn, base, size);
+}
+
+long __init lmb_overlaps_region(struct lmb_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 (lmb_addrs_overlap(base, size, rgnbase, rgnsize))
+                        break;
+        }
+
+        return (i < rgn->cnt) ? i : -1;
+}
+
+static u64 lmb_align_down(u64 addr, u64 size)
+{
+        return addr & ~(size - 1);
+}
+
+static u64 lmb_align_up(u64 addr, u64 size)
+{
+        return (addr + (size - 1)) & ~(size - 1);
+}
+
+static u64 __init lmb_alloc_nid_unreserved(u64 start, u64 end,
+                                           u64 size, u64 align)
+{
+        u64 base, res_base;
+        long j;
+
+        base = lmb_align_down((end - size), align);
+        while (start <= base) {
+                j = lmb_overlaps_region(&lmb.reserved, base, size);
+                if (j < 0) {
+                        /* this area isn't reserved, take it */
+                        if (lmb_add_region(&lmb.reserved, base,
+                                           lmb_align_up(size, align)) < 0)
+                                base = ~(u64)0;
+                        return base;
+                }
+                res_base = lmb.reserved.region[j].base;
+                if (res_base < size)
+                        break;
+                base = lmb_align_down(res_base - size, align);
+        }
+
+        return ~(u64)0;
+}
+
+static u64 __init lmb_alloc_nid_region(struct lmb_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 = lmb_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 = lmb_alloc_nid_unreserved(start, this_end,
+                                                           size, align);
+                        if (ret != ~(u64)0)
+                                return ret;
+                }
+                start = this_end;
+        }
+
+        return ~(u64)0;
+}
+
+u64 __init lmb_alloc_nid(u64 size, u64 align, int nid,
+                         u64 (*nid_range)(u64 start, u64 end, int *nid))
+{
+        struct lmb_region *mem = &lmb.memory;
+        int i;
+
+        for (i = 0; i < mem->cnt; i++) {
+                u64 ret = lmb_alloc_nid_region(&mem->region[i],
+                                               nid_range,
+                                               size, align, nid);
+                if (ret != ~(u64)0)
+                        return ret;
+        }
+
+        return lmb_alloc(size, align);
+}
+
+u64 __init lmb_alloc(u64 size, u64 align)
+{
+        return lmb_alloc_base(size, align, LMB_ALLOC_ANYWHERE);
+}
+
+u64 __init lmb_alloc_base(u64 size, u64 align, u64 max_addr)
+{
+        u64 alloc;
+
+        alloc = __lmb_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 __lmb_alloc_base(u64 size, u64 align, u64 max_addr)
+{
+        long i, j;
+        u64 base = 0;
+        u64 res_base;
+
+        BUG_ON(0 == size);
+
+        /* On some platforms, make sure we allocate lowmem */
+        /* Note that LMB_REAL_LIMIT may be LMB_ALLOC_ANYWHERE */
+        if (max_addr == LMB_ALLOC_ANYWHERE)
+                max_addr = LMB_REAL_LIMIT;
+
+        for (i = lmb.memory.cnt - 1; i >= 0; i--) {
+                u64 lmbbase = lmb.memory.region[i].base;
+                u64 lmbsize = lmb.memory.region[i].size;
+
+                if (lmbsize < size)
+                        continue;
+                if (max_addr == LMB_ALLOC_ANYWHERE)
+                        base = lmb_align_down(lmbbase + lmbsize - size, align);
+                else if (lmbbase < max_addr) {
+                        base = min(lmbbase + lmbsize, max_addr);
+                        base = lmb_align_down(base - size, align);
+                } else
+                        continue;
+
+                while (base && lmbbase <= base) {
+                        j = lmb_overlaps_region(&lmb.reserved, base, size);
+                        if (j < 0) {
+                                /* this area isn't reserved, take it */
+                                if (lmb_add_region(&lmb.reserved, base,
+                                                   lmb_align_up(size, align)) < 0)
+                                        return 0;
+                                return base;
+                        }
+                        res_base = lmb.reserved.region[j].base;
+                        if (res_base < size)
+                                break;
+                        base = lmb_align_down(res_base - size, align);
+                }
+        }
+        return 0;
+}
+
+/* You must call lmb_analyze() before this. */
+u64 __init lmb_phys_mem_size(void)
+{
+        return lmb.memory.size;
+}
+
+u64 __init lmb_end_of_DRAM(void)
+{
+        int idx = lmb.memory.cnt - 1;
+
+        return (lmb.memory.region[idx].base + lmb.memory.region[idx].size);
+}
+
+/* You must call lmb_analyze() after this. */
+void __init lmb_enforce_memory_limit(u64 memory_limit)
+{
+        unsigned long i;
+        u64 limit;
+        struct lmb_property *p;
+
+        if (!memory_limit)
+                return;
+
+        /* Truncate the lmb regions to satisfy the memory limit. */
+        limit = memory_limit;
+        for (i = 0; i < lmb.memory.cnt; i++) {
+                if (limit > lmb.memory.region[i].size) {
+                        limit -= lmb.memory.region[i].size;
+                        continue;
+                }
+
+                lmb.memory.region[i].size = limit;
+                lmb.memory.cnt = i + 1;
+                break;
+        }
+
+        if (lmb.memory.region[0].size < lmb.rmo_size)
+                lmb.rmo_size = lmb.memory.region[0].size;
+
+        /* And truncate any reserves above the limit also. */
+        for (i = 0; i < lmb.reserved.cnt; i++) {
+                p = &lmb.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) {
+                        lmb_remove_region(&lmb.reserved, i);
+                        i--;
+                }
+        }
+}
+
+int __init lmb_is_reserved(u64 addr)
+{
+        int i;
+
+        for (i = 0; i < lmb.reserved.cnt; i++) {
+                u64 upper = lmb.reserved.region[i].base +
+                        lmb.reserved.region[i].size - 1;
+                if ((addr >= lmb.reserved.region[i].base) && (addr <= upper))
+                        return 1;
+        }
+        return 0;
+}
+
+/*
+ * Given a <base, len>, find which memory regions belong to this range.
+ * Adjust the request and return a contiguous chunk.
+ */
+int lmb_find(struct lmb_property *res)
+{
+        int i;
+        u64 rstart, rend;
+
+        rstart = res->base;
+        rend = rstart + res->size - 1;
+
+        for (i = 0; i < lmb.memory.cnt; i++) {
+                u64 start = lmb.memory.region[i].base;
+                u64 end = start + lmb.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;
+}