To support deferred initialization of page structs for preserved
pages, add an iterator of the memblock reserved list that can select or
exclude ranges based on memblock flags.

Signed-off-by: Anthony Yznaga <anthony.yzn...@oracle.com>
---
 include/linux/memblock.h | 10 ++++++++++
 mm/memblock.c            | 51 +++++++++++++++++++++++++++++++++++++++++++++++-
 2 files changed, 60 insertions(+), 1 deletion(-)

diff --git a/include/linux/memblock.h b/include/linux/memblock.h
index 27ab2b30ae1d..f348ebb750c9 100644
--- a/include/linux/memblock.h
+++ b/include/linux/memblock.h
@@ -145,6 +145,11 @@ void __next_mem_range_rev(u64 *idx, int nid, enum 
memblock_flags flags,
 void __next_reserved_mem_region(u64 *idx, phys_addr_t *out_start,
                                phys_addr_t *out_end);
 
+void __next_reserved_mem_range(u64 *idx, enum memblock_flags flags,
+                              enum memblock_flags exclflags,
+                              phys_addr_t *out_start, phys_addr_t *out_end,
+                              int *out_nid);
+
 void __memblock_free_late(phys_addr_t base, phys_addr_t size);
 
 /**
@@ -202,6 +207,11 @@ void __memblock_free_late(phys_addr_t base, phys_addr_t 
size);
             i != (u64)ULLONG_MAX;                                      \
             __next_reserved_mem_region(&i, p_start, p_end))
 
+#define for_each_reserved_mem_range(i, flags, exclflags, p_start, p_end, 
p_nid)\
+       for (i = 0UL, __next_reserved_mem_range(&i, flags, exclflags, p_start, 
p_end, p_nid);   \
+            i != (u64)ULLONG_MAX;                                      \
+            __next_reserved_mem_range(&i, flags, exclflags, p_start, p_end, 
p_nid))
+
 static inline bool memblock_is_hotpluggable(struct memblock_region *m)
 {
        return m->flags & MEMBLOCK_HOTPLUG;
diff --git a/mm/memblock.c b/mm/memblock.c
index 1a9a2055ed11..33597f352dc0 100644
--- a/mm/memblock.c
+++ b/mm/memblock.c
@@ -987,6 +987,55 @@ void __init_memblock __next_reserved_mem_region(u64 *idx,
        *idx = ULLONG_MAX;
 }
 
+/**
+ * __next_reserved_mem_range - next function for for_each_reserved_range()
+ * @idx: pointer to u64 loop variable
+ * @flags: pick blocks based on memory attributes
+ * @exclflags: exclude blocks based on memory attributes
+ * @out_start: ptr to phys_addr_t for start address of the range, can be %NULL
+ * @out_end: ptr to phys_addr_t for end address of the range, can be %NULL
+ * @out_nid: ptr to int for nid of the range, can be %NULL
+ *
+ * Iterate over all reserved memory ranges.
+ */
+void __init_memblock __next_reserved_mem_range(u64 *idx,
+                                          enum memblock_flags flags,
+                                          enum memblock_flags exclflags,
+                                          phys_addr_t *out_start,
+                                          phys_addr_t *out_end, int *out_nid)
+{
+       struct memblock_type *type = &memblock.reserved;
+       int _idx = *idx;
+
+       for (; _idx < type->cnt; _idx++) {
+               struct memblock_region *r = &type->regions[_idx];
+               phys_addr_t base = r->base;
+               phys_addr_t size = r->size;
+
+               /* skip preserved pages */
+               if ((exclflags & MEMBLOCK_PRESERVED) && 
memblock_is_preserved(r))
+                       continue;
+
+               /* skip non-preserved pages */
+               if ((flags & MEMBLOCK_PRESERVED) && !memblock_is_preserved(r))
+                       continue;
+
+               if (out_start)
+                       *out_start = base;
+               if (out_end)
+                       *out_end = base + size - 1;
+               if (out_nid)
+                       *out_nid = r->nid;
+
+               _idx++;
+               *idx = (u64)_idx;
+               return;
+       }
+
+       /* signal end of iteration */
+       *idx = ULLONG_MAX;
+}
+
 static bool should_skip_region(struct memblock_region *m, int nid, int flags)
 {
        int m_nid = memblock_get_region_node(m);
@@ -1011,7 +1060,7 @@ static bool should_skip_region(struct memblock_region *m, 
int nid, int flags)
 }
 
 /**
- * __next_mem_range - next function for for_each_free_mem_range() etc.
+ * __next__mem_range - next function for for_each_free_mem_range() etc.
  * @idx: pointer to u64 loop variable
  * @nid: node selector, %NUMA_NO_NODE for all nodes
  * @flags: pick from blocks based on memory attributes
-- 
2.13.3

Reply via email to