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authorSimon Rettberg2019-09-03 19:28:47 +0200
committerSimon Rettberg2019-09-03 19:28:47 +0200
commit4578e890e44e55c71736e77ca92ce5a2a5d3bc9a (patch)
tree7c1ed4720326d628c6cb6b68160576c4a6a0f08d /src/server/image.c
parent[SERVER] Move signal init to uplink_init (diff)
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[SERVER] Fix image_updateCachemap()
Diffstat (limited to 'src/server/image.c')
-rw-r--r--src/server/image.c12
1 files changed, 8 insertions, 4 deletions
diff --git a/src/server/image.c b/src/server/image.c
index b349058..484a28f 100644
--- a/src/server/image.c
+++ b/src/server/image.c
@@ -126,11 +126,15 @@ void image_updateCachemap(dnbd3_image_t *image, uint64_t start, uint64_t end, co
fb |= bit_mask;
}
// Last byte
- for ( pos = lastByteInMap << 15; pos < end; pos += DNBD3_BLOCK_SIZE ) {
- const int map_x = (pos >> 12) & 7; // mod 8
- const uint8_t bit_mask = (uint8_t)( 1 << map_x );
- lb |= bit_mask;
+ if ( lastByteInMap != firstByteInMap ) {
+ for ( pos = lastByteInMap << 15; pos < end; pos += DNBD3_BLOCK_SIZE ) {
+ assert( lastByteInMap == (pos >> 15) );
+ const int map_x = (pos >> 12) & 7; // mod 8
+ const uint8_t bit_mask = (uint8_t)( 1 << map_x );
+ lb |= bit_mask;
+ }
}
+ atomic_thread_fence( memory_order_acquire );
if ( set ) {
uint8_t fo = atomic_fetch_or_explicit( &cache->map[firstByteInMap], fb, memory_order_relaxed );
uint8_t lo = atomic_fetch_or_explicit( &cache->map[lastByteInMap], lb, memory_order_relaxed );