1 files changed, 141 insertions, 44 deletions

diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c
index d9a181351332..6cf5c71c431f 100644
--- a/arch/powerpc/mm/numa.c
+++ b/arch/powerpc/mm/numa.c
@@ -89,6 +89,46 @@ static int __cpuinit fake_numa_create_new_node(unsigned long end_pfn,
         return 0;
 }
 
+/*
+ * get_active_region_work_fn - A helper function for get_node_active_region
+ *      Returns datax set to the start_pfn and end_pfn if they contain
+ *      the initial value of datax->start_pfn between them
+ * @start_pfn: start page(inclusive) of region to check
+ * @end_pfn: end page(exclusive) of region to check
+ * @datax: comes in with ->start_pfn set to value to search for and
+ *      goes out with active range if it contains it
+ * Returns 1 if search value is in range else 0
+ */
+static int __init get_active_region_work_fn(unsigned long start_pfn,
+                                        unsigned long end_pfn, void *datax)
+{
+        struct node_active_region *data;
+        data = (struct node_active_region *)datax;
+
+        if (start_pfn <= data->start_pfn && end_pfn > data->start_pfn) {
+                data->start_pfn = start_pfn;
+                data->end_pfn = end_pfn;
+                return 1;
+        }
+        return 0;
+
+}
+
+/*
+ * get_node_active_region - Return active region containing start_pfn
+ * @start_pfn: The page to return the region for.
+ * @node_ar: Returned set to the active region containing start_pfn
+ */
+static void __init get_node_active_region(unsigned long start_pfn,
+                       struct node_active_region *node_ar)
+{
+        int nid = early_pfn_to_nid(start_pfn);
+
+        node_ar->nid = nid;
+        node_ar->start_pfn = start_pfn;
+        work_with_active_regions(nid, get_active_region_work_fn, node_ar);
+}
+
 static void __cpuinit map_cpu_to_node(int cpu, int node)
 {
         numa_cpu_lookup_table[cpu] = node;
@@ -150,6 +190,21 @@ static const int *of_get_associativity(struct device_node *dev)
         return of_get_property(dev, "ibm,associativity", NULL);
 }
 
+/*
+ * Returns the property linux,drconf-usable-memory if
+ * it exists (the property exists only in kexec/kdump kernels,
+ * added by kexec-tools)
+ */
+static const u32 *of_get_usable_memory(struct device_node *memory)
+{
+        const u32 *prop;
+        u32 len;
+        prop = of_get_property(memory, "linux,drconf-usable-memory", &len);
+        if (!prop || len < sizeof(unsigned int))
+                return 0;
+        return prop;
+}
+
 /* Returns nid in the range [0..MAX_NUMNODES-1], or -1 if no useful numa
  * info is found.
  */
@@ -487,14 +542,29 @@ static unsigned long __init numa_enforce_memory_limit(unsigned long start,
 }
 
 /*
+ * Reads the counter for a given entry in
+ * linux,drconf-usable-memory property
+ */
+static inline int __init read_usm_ranges(const u32 **usm)
+{
+        /*
+         * For each lmb in ibm,dynamic-memory a corresponding
+         * entry in linux,drconf-usable-memory property contains
+         * a counter followed by that many (base, size) duple.
+         * read the counter from linux,drconf-usable-memory
+         */
+        return read_n_cells(n_mem_size_cells, usm);
+}
+
+/*
  * Extract NUMA information from the ibm,dynamic-reconfiguration-memory
  * node.  This assumes n_mem_{addr,size}_cells have been set.
  */
 static void __init parse_drconf_memory(struct device_node *memory)
 {
-        const u32 *dm;
-        unsigned int n, rc;
-        unsigned long lmb_size, size;
+        const u32 *dm, *usm;
+        unsigned int n, rc, ranges, is_kexec_kdump = 0;
+        unsigned long lmb_size, base, size, sz;
         int nid;
         struct assoc_arrays aa;
 
@@ -510,6 +580,11 @@ static void __init parse_drconf_memory(struct device_node *memory)
         if (rc)
                 return;
 
+        /* check if this is a kexec/kdump kernel */
+        usm = of_get_usable_memory(memory);
+        if (usm != NULL)
+                is_kexec_kdump = 1;
+
         for (; n != 0; --n) {
                 struct of_drconf_cell drmem;
 
@@ -521,21 +596,31 @@ static void __init parse_drconf_memory(struct device_node *memory)
                     || !(drmem.flags & DRCONF_MEM_ASSIGNED))
                         continue;
 
-                nid = of_drconf_to_nid_single(&drmem, &aa);
+                base = drmem.base_addr;
+                size = lmb_size;
+                ranges = 1;
 
-                fake_numa_create_new_node(
-                                ((drmem.base_addr + lmb_size) >> PAGE_SHIFT),
+                if (is_kexec_kdump) {
+                        ranges = read_usm_ranges(&usm);
+                        if (!ranges) /* there are no (base, size) duple */
+                                continue;
+                }
+                do {
+                        if (is_kexec_kdump) {
+                                base = read_n_cells(n_mem_addr_cells, &usm);
+                                size = read_n_cells(n_mem_size_cells, &usm);
+                        }
+                        nid = of_drconf_to_nid_single(&drmem, &aa);
+                        fake_numa_create_new_node(
+                                ((base + size) >> PAGE_SHIFT),
                                            &nid);
-
-                node_set_online(nid);
-
-                size = numa_enforce_memory_limit(drmem.base_addr, lmb_size);
-                if (!size)
-                        continue;
-
-                add_active_range(nid, drmem.base_addr >> PAGE_SHIFT,
-                                 (drmem.base_addr >> PAGE_SHIFT)
-                                 + (size >> PAGE_SHIFT));
+                        node_set_online(nid);
+                        sz = numa_enforce_memory_limit(base, size);
+                        if (sz)
+                                add_active_range(nid, base >> PAGE_SHIFT,
+                                                 (base >> PAGE_SHIFT)
+                                                 + (sz >> PAGE_SHIFT));
+                } while (--ranges);
         }
 }
 
@@ -837,38 +922,50 @@ void __init do_init_bootmem(void)
                                   start_pfn, end_pfn);
 
                 free_bootmem_with_active_regions(nid, end_pfn);
+        }
 
-                /* Mark reserved regions on this node */
-                for (i = 0; i < lmb.reserved.cnt; i++) {
-                        unsigned long physbase = lmb.reserved.region[i].base;
-                        unsigned long size = lmb.reserved.region[i].size;
-                        unsigned long start_paddr = start_pfn << PAGE_SHIFT;
-                        unsigned long end_paddr = end_pfn << PAGE_SHIFT;
-
-                        if (early_pfn_to_nid(physbase >> PAGE_SHIFT) != nid &&
-                            early_pfn_to_nid((physbase+size-1) >> PAGE_SHIFT) != nid)
-                                continue;
-
-                        if (physbase < end_paddr &&
-                            (physbase+size) > start_paddr) {
-                                /* overlaps */
-                                if (physbase < start_paddr) {
-                                        size -= start_paddr - physbase;
-                                        physbase = start_paddr;
-                                }
-
-                                if (size > end_paddr - physbase)
-                                        size = end_paddr - physbase;
-
-                                dbg("reserve_bootmem %lx %lx\n", physbase,
-                                    size);
-                                reserve_bootmem_node(NODE_DATA(nid), physbase,
-                                                     size, BOOTMEM_DEFAULT);
-                        }
+        /* Mark reserved regions */
+        for (i = 0; i < lmb.reserved.cnt; i++) {
+                unsigned long physbase = lmb.reserved.region[i].base;
+                unsigned long size = lmb.reserved.region[i].size;
+                unsigned long start_pfn = physbase >> PAGE_SHIFT;
+                unsigned long end_pfn = ((physbase + size) >> PAGE_SHIFT);
+                struct node_active_region node_ar;
+
+                get_node_active_region(start_pfn, &node_ar);
+                while (start_pfn < end_pfn) {
+                        /*
+                         * if reserved region extends past active region
+                         * then trim size to active region
+                         */
+                        if (end_pfn > node_ar.end_pfn)
+                                size = (node_ar.end_pfn << PAGE_SHIFT)
+                                        - (start_pfn << PAGE_SHIFT);
+                        dbg("reserve_bootmem %lx %lx nid=%d\n", physbase, size,
+                                node_ar.nid);
+                        reserve_bootmem_node(NODE_DATA(node_ar.nid), physbase,
+                                                size, BOOTMEM_DEFAULT);
+                        /*
+                         * if reserved region is contained in the active region
+                         * then done.
+                         */
+                        if (end_pfn <= node_ar.end_pfn)
+                                break;
+
+                        /*
+                         * reserved region extends past the active region
+                         *   get next active region that contains this
+                         *   reserved region
+                         */
+                        start_pfn = node_ar.end_pfn;
+                        physbase = start_pfn << PAGE_SHIFT;
+                        get_node_active_region(start_pfn, &node_ar);
                 }
 
-                sparse_memory_present_with_active_regions(nid);
         }
+
+        for_each_online_node(nid)
+                sparse_memory_present_with_active_regions(nid);
 }
 
 void __init paging_init(void)