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authorJoerg Roedel <jroedel@suse.de>2014-07-21 12:26:58 +0200
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>2014-07-29 01:47:44 +0200
commit07a338236fdcd6caf41541dcdf879f5758020ab1 (patch)
treefd6dadad36b3c75547ca33e0006a0a00d212fe75
parentf469f02dc6fa67f6c6a7d91400d08b9339147aed (diff)
downloadop-kernel-dev-07a338236fdcd6caf41541dcdf879f5758020ab1.zip
op-kernel-dev-07a338236fdcd6caf41541dcdf879f5758020ab1.tar.gz
PM / Hibernate: Add memory_rtree_find_bit function
Add a function to find a bit in the radix tree for a given pfn. Also add code to the memory bitmap wrapper functions to use the radix tree together with the existing memory bitmap implementation. On read accesses compare the results of both bitmaps to make sure the radix tree behaves the same way. Signed-off-by: Joerg Roedel <jroedel@suse.de> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
-rw-r--r--kernel/power/snapshot.c84
1 files changed, 81 insertions, 3 deletions
diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c
index 5a0eafd..0b7f934 100644
--- a/kernel/power/snapshot.c
+++ b/kernel/power/snapshot.c
@@ -720,6 +720,56 @@ static int memory_bm_find_bit(struct memory_bitmap *bm, unsigned long pfn,
return 0;
}
+/*
+ * memory_rtree_find_bit - Find the bit for pfn in the memory
+ * bitmap
+ *
+ * Walks the radix tree to find the page which contains the bit for
+ * pfn and returns the bit position in **addr and *bit_nr.
+ */
+static int memory_rtree_find_bit(struct memory_bitmap *bm, unsigned long pfn,
+ void **addr, unsigned int *bit_nr)
+{
+ struct mem_zone_bm_rtree *curr, *zone;
+ struct rtree_node *node;
+ int i, block_nr;
+
+ zone = NULL;
+
+ /* Find the right zone */
+ list_for_each_entry(curr, &bm->zones, list) {
+ if (pfn >= curr->start_pfn && pfn < curr->end_pfn) {
+ zone = curr;
+ break;
+ }
+ }
+
+ if (!zone)
+ return -EFAULT;
+
+ /*
+ * We have a zone. Now walk the radix tree to find the leave
+ * node for our pfn.
+ */
+ node = zone->rtree;
+ block_nr = (pfn - zone->start_pfn) >> BM_BLOCK_SHIFT;
+
+ for (i = zone->levels; i > 0; i--) {
+ int index;
+
+ index = block_nr >> ((i - 1) * BM_RTREE_LEVEL_SHIFT);
+ index &= BM_RTREE_LEVEL_MASK;
+ BUG_ON(node->data[index] == 0);
+ node = (struct rtree_node *)node->data[index];
+ }
+
+ /* Set return values */
+ *addr = node->data;
+ *bit_nr = (pfn - zone->start_pfn) & BM_BLOCK_MASK;
+
+ return 0;
+}
+
static void memory_bm_set_bit(struct memory_bitmap *bm, unsigned long pfn)
{
void *addr;
@@ -729,6 +779,10 @@ static void memory_bm_set_bit(struct memory_bitmap *bm, unsigned long pfn)
error = memory_bm_find_bit(bm, pfn, &addr, &bit);
BUG_ON(error);
set_bit(bit, addr);
+
+ error = memory_rtree_find_bit(bm, pfn, &addr, &bit);
+ BUG_ON(error);
+ set_bit(bit, addr);
}
static int mem_bm_set_bit_check(struct memory_bitmap *bm, unsigned long pfn)
@@ -740,6 +794,13 @@ static int mem_bm_set_bit_check(struct memory_bitmap *bm, unsigned long pfn)
error = memory_bm_find_bit(bm, pfn, &addr, &bit);
if (!error)
set_bit(bit, addr);
+ else
+ return error;
+
+ error = memory_rtree_find_bit(bm, pfn, &addr, &bit);
+ if (!error)
+ set_bit(bit, addr);
+
return error;
}
@@ -752,25 +813,42 @@ static void memory_bm_clear_bit(struct memory_bitmap *bm, unsigned long pfn)
error = memory_bm_find_bit(bm, pfn, &addr, &bit);
BUG_ON(error);
clear_bit(bit, addr);
+
+ error = memory_rtree_find_bit(bm, pfn, &addr, &bit);
+ BUG_ON(error);
+ clear_bit(bit, addr);
}
static int memory_bm_test_bit(struct memory_bitmap *bm, unsigned long pfn)
{
void *addr;
unsigned int bit;
- int error;
+ int error, error2;
+ int v;
error = memory_bm_find_bit(bm, pfn, &addr, &bit);
BUG_ON(error);
- return test_bit(bit, addr);
+ v = test_bit(bit, addr);
+
+ error2 = memory_rtree_find_bit(bm, pfn, &addr, &bit);
+ BUG_ON(error2);
+
+ WARN_ON_ONCE(v != test_bit(bit, addr));
+
+ return v;
}
static bool memory_bm_pfn_present(struct memory_bitmap *bm, unsigned long pfn)
{
void *addr;
unsigned int bit;
+ int present;
+
+ present = !memory_bm_find_bit(bm, pfn, &addr, &bit);
+
+ WARN_ON_ONCE(present != !memory_rtree_find_bit(bm, pfn, &addr, &bit));
- return !memory_bm_find_bit(bm, pfn, &addr, &bit);
+ return present;
}
/**
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