1 files changed, 228 insertions, 4 deletions

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index f9e4e647d7e8..c3f6f851f76e 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -80,8 +80,9 @@ int sysctl_lowmem_reserve_ratio[MAX_NR_ZONES-1] = {
          256,
 #endif
 #ifdef CONFIG_HIGHMEM
-         32
+         32,
 #endif
+         32,
 };
 
 EXPORT_SYMBOL(totalram_pages);
@@ -95,8 +96,9 @@ static char * const zone_names[MAX_NR_ZONES] = {
 #endif
          "Normal",
 #ifdef CONFIG_HIGHMEM
-         "HighMem"
+         "HighMem",
 #endif
+         "Movable",
 };
 
 int min_free_kbytes = 1024;
@@ -134,6 +136,12 @@ static unsigned long __meminitdata dma_reserve;
   static unsigned long __meminitdata node_boundary_start_pfn[MAX_NUMNODES];
   static unsigned long __meminitdata node_boundary_end_pfn[MAX_NUMNODES];
 #endif /* CONFIG_MEMORY_HOTPLUG_RESERVE */
+  unsigned long __initdata required_kernelcore;
+  unsigned long __initdata zone_movable_pfn[MAX_NUMNODES];
+
+  /* movable_zone is the "real" zone pages in ZONE_MOVABLE are taken from */
+  int movable_zone;
+  EXPORT_SYMBOL(movable_zone);
 #endif /* CONFIG_ARCH_POPULATES_NODE_MAP */
 
 #if MAX_NUMNODES > 1
@@ -1480,7 +1488,7 @@ unsigned int nr_free_buffer_pages(void)
  */
 unsigned int nr_free_pagecache_pages(void)
 {
-        return nr_free_zone_pages(gfp_zone(GFP_HIGHUSER));
+        return nr_free_zone_pages(gfp_zone(GFP_HIGHUSER_MOVABLE));
 }
 
 static inline void show_node(struct zone *zone)
@@ -2667,6 +2675,63 @@ void __meminit get_pfn_range_for_nid(unsigned int nid,
 }
 
 /*
+ * This finds a zone that can be used for ZONE_MOVABLE pages. The
+ * assumption is made that zones within a node are ordered in monotonic
+ * increasing memory addresses so that the "highest" populated zone is used
+ */
+void __init find_usable_zone_for_movable(void)
+{
+        int zone_index;
+        for (zone_index = MAX_NR_ZONES - 1; zone_index >= 0; zone_index--) {
+                if (zone_index == ZONE_MOVABLE)
+                        continue;
+
+                if (arch_zone_highest_possible_pfn[zone_index] >
+                                arch_zone_lowest_possible_pfn[zone_index])
+                        break;
+        }
+
+        VM_BUG_ON(zone_index == -1);
+        movable_zone = zone_index;
+}
+
+/*
+ * The zone ranges provided by the architecture do not include ZONE_MOVABLE
+ * because it is sized independant of architecture. Unlike the other zones,
+ * the starting point for ZONE_MOVABLE is not fixed. It may be different
+ * in each node depending on the size of each node and how evenly kernelcore
+ * is distributed. This helper function adjusts the zone ranges
+ * provided by the architecture for a given node by using the end of the
+ * highest usable zone for ZONE_MOVABLE. This preserves the assumption that
+ * zones within a node are in order of monotonic increases memory addresses
+ */
+void __meminit adjust_zone_range_for_zone_movable(int nid,
+                                        unsigned long zone_type,
+                                        unsigned long node_start_pfn,
+                                        unsigned long node_end_pfn,
+                                        unsigned long *zone_start_pfn,
+                                        unsigned long *zone_end_pfn)
+{
+        /* Only adjust if ZONE_MOVABLE is on this node */
+        if (zone_movable_pfn[nid]) {
+                /* Size ZONE_MOVABLE */
+                if (zone_type == ZONE_MOVABLE) {
+                        *zone_start_pfn = zone_movable_pfn[nid];
+                        *zone_end_pfn = min(node_end_pfn,
+                                arch_zone_highest_possible_pfn[movable_zone]);
+
+                /* Adjust for ZONE_MOVABLE starting within this range */
+                } else if (*zone_start_pfn < zone_movable_pfn[nid] &&
+                                *zone_end_pfn > zone_movable_pfn[nid]) {
+                        *zone_end_pfn = zone_movable_pfn[nid];
+
+                /* Check if this whole range is within ZONE_MOVABLE */
+                } else if (*zone_start_pfn >= zone_movable_pfn[nid])
+                        *zone_start_pfn = *zone_end_pfn;
+        }
+}
+
+/*
  * Return the number of pages a zone spans in a node, including holes
  * present_pages = zone_spanned_pages_in_node() - zone_absent_pages_in_node()
  */
@@ -2681,6 +2746,9 @@ static unsigned long __meminit zone_spanned_pages_in_node(int nid,
         get_pfn_range_for_nid(nid, &node_start_pfn, &node_end_pfn);
         zone_start_pfn = arch_zone_lowest_possible_pfn[zone_type];
         zone_end_pfn = arch_zone_highest_possible_pfn[zone_type];
+        adjust_zone_range_for_zone_movable(nid, zone_type,
+                                node_start_pfn, node_end_pfn,
+                                &zone_start_pfn, &zone_end_pfn);
 
         /* Check that this node has pages within the zone's required range */
         if (zone_end_pfn < node_start_pfn || zone_start_pfn > node_end_pfn)
@@ -2771,6 +2839,9 @@ static unsigned long __meminit zone_absent_pages_in_node(int nid,
         zone_end_pfn = min(arch_zone_highest_possible_pfn[zone_type],
                                                         node_end_pfn);
 
+        adjust_zone_range_for_zone_movable(nid, zone_type,
+                        node_start_pfn, node_end_pfn,
+                        &zone_start_pfn, &zone_end_pfn);
         return __absent_pages_in_range(nid, zone_start_pfn, zone_end_pfn);
 }
 
@@ -3148,6 +3219,122 @@ unsigned long __init find_max_pfn_with_active_regions(void)
         return max_pfn;
 }
 
+/*
+ * Find the PFN the Movable zone begins in each node. Kernel memory
+ * is spread evenly between nodes as long as the nodes have enough
+ * memory. When they don't, some nodes will have more kernelcore than
+ * others
+ */
+void __init find_zone_movable_pfns_for_nodes(unsigned long *movable_pfn)
+{
+        int i, nid;
+        unsigned long usable_startpfn;
+        unsigned long kernelcore_node, kernelcore_remaining;
+        int usable_nodes = num_online_nodes();
+
+        /* If kernelcore was not specified, there is no ZONE_MOVABLE */
+        if (!required_kernelcore)
+                return;
+
+        /* usable_startpfn is the lowest possible pfn ZONE_MOVABLE can be at */
+        find_usable_zone_for_movable();
+        usable_startpfn = arch_zone_lowest_possible_pfn[movable_zone];
+
+restart:
+        /* Spread kernelcore memory as evenly as possible throughout nodes */
+        kernelcore_node = required_kernelcore / usable_nodes;
+        for_each_online_node(nid) {
+                /*
+                 * Recalculate kernelcore_node if the division per node
+                 * now exceeds what is necessary to satisfy the requested
+                 * amount of memory for the kernel
+                 */
+                if (required_kernelcore < kernelcore_node)
+                        kernelcore_node = required_kernelcore / usable_nodes;
+
+                /*
+                 * As the map is walked, we track how much memory is usable
+                 * by the kernel using kernelcore_remaining. When it is
+                 * 0, the rest of the node is usable by ZONE_MOVABLE
+                 */
+                kernelcore_remaining = kernelcore_node;
+
+                /* Go through each range of PFNs within this node */
+                for_each_active_range_index_in_nid(i, nid) {
+                        unsigned long start_pfn, end_pfn;
+                        unsigned long size_pages;
+
+                        start_pfn = max(early_node_map[i].start_pfn,
+                                                zone_movable_pfn[nid]);
+                        end_pfn = early_node_map[i].end_pfn;
+                        if (start_pfn >= end_pfn)
+                                continue;
+
+                        /* Account for what is only usable for kernelcore */
+                        if (start_pfn < usable_startpfn) {
+                                unsigned long kernel_pages;
+                                kernel_pages = min(end_pfn, usable_startpfn)
+                                                                - start_pfn;
+
+                                kernelcore_remaining -= min(kernel_pages,
+                                                        kernelcore_remaining);
+                                required_kernelcore -= min(kernel_pages,
+                                                        required_kernelcore);
+
+                                /* Continue if range is now fully accounted */
+                                if (end_pfn <= usable_startpfn) {
+
+                                        /*
+                                         * Push zone_movable_pfn to the end so
+                                         * that if we have to rebalance
+                                         * kernelcore across nodes, we will
+                                         * not double account here
+                                         */
+                                        zone_movable_pfn[nid] = end_pfn;
+                                        continue;
+                                }
+                                start_pfn = usable_startpfn;
+                        }
+
+                        /*
+                         * The usable PFN range for ZONE_MOVABLE is from
+                         * start_pfn->end_pfn. Calculate size_pages as the
+                         * number of pages used as kernelcore
+                         */
+                        size_pages = end_pfn - start_pfn;
+                        if (size_pages > kernelcore_remaining)
+                                size_pages = kernelcore_remaining;
+                        zone_movable_pfn[nid] = start_pfn + size_pages;
+
+                        /*
+                         * Some kernelcore has been met, update counts and
+                         * break if the kernelcore for this node has been
+                         * satisified
+                         */
+                        required_kernelcore -= min(required_kernelcore,
+                                                                size_pages);
+                        kernelcore_remaining -= size_pages;
+                        if (!kernelcore_remaining)
+                                break;
+                }
+        }
+
+        /*
+         * If there is still required_kernelcore, we do another pass with one
+         * less node in the count. This will push zone_movable_pfn[nid] further
+         * along on the nodes that still have memory until kernelcore is
+         * satisified
+         */
+        usable_nodes--;
+        if (usable_nodes && required_kernelcore > usable_nodes)
+                goto restart;
+
+        /* Align start of ZONE_MOVABLE on all nids to MAX_ORDER_NR_PAGES */
+        for (nid = 0; nid < MAX_NUMNODES; nid++)
+                zone_movable_pfn[nid] =
+                        roundup(zone_movable_pfn[nid], MAX_ORDER_NR_PAGES);
+}
+
 /**
  * free_area_init_nodes - Initialise all pg_data_t and zone data
  * @max_zone_pfn: an array of max PFNs for each zone
@@ -3177,19 +3364,37 @@ void __init free_area_init_nodes(unsigned long *max_zone_pfn)
         arch_zone_lowest_possible_pfn[0] = find_min_pfn_with_active_regions();
         arch_zone_highest_possible_pfn[0] = max_zone_pfn[0];
         for (i = 1; i < MAX_NR_ZONES; i++) {
+                if (i == ZONE_MOVABLE)
+                        continue;
                 arch_zone_lowest_possible_pfn[i] =
                         arch_zone_highest_possible_pfn[i-1];
                 arch_zone_highest_possible_pfn[i] =
                         max(max_zone_pfn[i], arch_zone_lowest_possible_pfn[i]);
         }
+        arch_zone_lowest_possible_pfn[ZONE_MOVABLE] = 0;
+        arch_zone_highest_possible_pfn[ZONE_MOVABLE] = 0;
+
+        /* Find the PFNs that ZONE_MOVABLE begins at in each node */
+        memset(zone_movable_pfn, 0, sizeof(zone_movable_pfn));
+        find_zone_movable_pfns_for_nodes(zone_movable_pfn);
 
         /* Print out the zone ranges */
         printk("Zone PFN ranges:\n");
-        for (i = 0; i < MAX_NR_ZONES; i++)
+        for (i = 0; i < MAX_NR_ZONES; i++) {
+                if (i == ZONE_MOVABLE)
+                        continue;
                 printk("  %-8s %8lu -> %8lu\n",
                                 zone_names[i],
                                 arch_zone_lowest_possible_pfn[i],
                                 arch_zone_highest_possible_pfn[i]);
+        }
+
+        /* Print out the PFNs ZONE_MOVABLE begins at in each node */
+        printk("Movable zone start PFN for each node\n");
+        for (i = 0; i < MAX_NUMNODES; i++) {
+                if (zone_movable_pfn[i])
+                        printk("  Node %d: %lu\n", i, zone_movable_pfn[i]);
+        }
 
         /* Print out the early_node_map[] */
         printk("early_node_map[%d] active PFN ranges\n", nr_nodemap_entries);
@@ -3206,6 +3411,25 @@ void __init free_area_init_nodes(unsigned long *max_zone_pfn)
                                 find_min_pfn_for_node(nid), NULL);
         }
 }
+
+/*
+ * kernelcore=size sets the amount of memory for use for allocations that
+ * cannot be reclaimed or migrated.
+ */
+int __init cmdline_parse_kernelcore(char *p)
+{
+        unsigned long long coremem;
+        if (!p)
+                return -EINVAL;
+
+        coremem = memparse(p, &p);
+        required_kernelcore = coremem >> PAGE_SHIFT;
+
+        /* Paranoid check that UL is enough for required_kernelcore */
+        WARN_ON((coremem >> PAGE_SHIFT) > ULONG_MAX);
+
+        return 0;
+}
 #endif /* CONFIG_ARCH_POPULATES_NODE_MAP */
 
 /**