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authorPeter Maydell <peter.maydell@linaro.org>2017-12-19 17:44:42 +0000
committerPeter Maydell <peter.maydell@linaro.org>2017-12-19 17:44:42 +0000
commit03c1c09d56bb242696fa07f9842b3a8f9fbcd46f (patch)
tree52ae405d1af375cee2d9b074366eddb71a2ca99c /util/hbitmap.c
parent062fcb27c4c1af6902f497ec9316c1c0ead90e81 (diff)
parent996922de45299878cdc4c15b72b19edf2bc618a4 (diff)
downloadfocaccia-qemu-03c1c09d56bb242696fa07f9842b3a8f9fbcd46f.tar.gz
focaccia-qemu-03c1c09d56bb242696fa07f9842b3a8f9fbcd46f.zip
Merge remote-tracking branch 'remotes/cody/tags/block-pull-request' into staging
# gpg: Signature made Mon 18 Dec 2017 21:05:53 GMT
# gpg:                using RSA key 0xBDBE7B27C0DE3057
# gpg: Good signature from "Jeffrey Cody <jcody@redhat.com>"
# gpg:                 aka "Jeffrey Cody <jeff@codyprime.org>"
# gpg:                 aka "Jeffrey Cody <codyprime@gmail.com>"
# Primary key fingerprint: 9957 4B4D 3474 90E7 9D98  D624 BDBE 7B27 C0DE 3057

* remotes/cody/tags/block-pull-request:
  block/curl: fix minor memory leaks
  block/curl: check error return of curl_global_init()
  block/sheepdog: code beautification
  block/sheepdog: remove spurious NULL check
  blockjob: kick jobs on set-speed
  backup: use copy_bitmap in incremental backup
  backup: simplify non-dirty bits progress processing
  backup: init copy_bitmap from sync_bitmap for incremental
  backup: move from done_bitmap to copy_bitmap
  hbitmap: add next_zero function

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Diffstat (limited to 'util/hbitmap.c')
-rw-r--r--util/hbitmap.c39
1 files changed, 39 insertions, 0 deletions
diff --git a/util/hbitmap.c b/util/hbitmap.c
index 2f9d0fdbd0..289778a55c 100644
--- a/util/hbitmap.c
+++ b/util/hbitmap.c
@@ -188,6 +188,45 @@ void hbitmap_iter_init(HBitmapIter *hbi, const HBitmap *hb, uint64_t first)
     }
 }
 
+int64_t hbitmap_next_zero(const HBitmap *hb, uint64_t start)
+{
+    size_t pos = (start >> hb->granularity) >> BITS_PER_LEVEL;
+    unsigned long *last_lev = hb->levels[HBITMAP_LEVELS - 1];
+    uint64_t sz = hb->sizes[HBITMAP_LEVELS - 1];
+    unsigned long cur = last_lev[pos];
+    unsigned start_bit_offset =
+            (start >> hb->granularity) & (BITS_PER_LONG - 1);
+    int64_t res;
+
+    cur |= (1UL << start_bit_offset) - 1;
+    assert((start >> hb->granularity) < hb->size);
+
+    if (cur == (unsigned long)-1) {
+        do {
+            pos++;
+        } while (pos < sz && last_lev[pos] == (unsigned long)-1);
+
+        if (pos >= sz) {
+            return -1;
+        }
+
+        cur = last_lev[pos];
+    }
+
+    res = (pos << BITS_PER_LEVEL) + ctol(cur);
+    if (res >= hb->size) {
+        return -1;
+    }
+
+    res = res << hb->granularity;
+    if (res < start) {
+        assert(((start - res) >> hb->granularity) == 0);
+        return start;
+    }
+
+    return res;
+}
+
 bool hbitmap_empty(const HBitmap *hb)
 {
     return hb->count == 0;