[13/20] qcow2: Support external data file in qemu-img check
diff mbox series

Message ID 20190227172256.30368-14-kwolf@redhat.com
State New
Headers show
Series
  • qcow2: External data files
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Commit Message

Kevin Wolf Feb. 27, 2019, 5:22 p.m. UTC
For external data files, data clusters must be excluded from the
refcount calculations. Instead, an implicit refcount of 1 is assumed for
the COPIED flag.

Compressed clusters and internal snapshots are incompatible with
external data files, so print an error if they are in use for images
with an external data file.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
---
 block/qcow2-refcount.c | 41 ++++++++++++++++++++++++++++++-----------
 1 file changed, 30 insertions(+), 11 deletions(-)

Patch
diff mbox series

diff --git a/block/qcow2-refcount.c b/block/qcow2-refcount.c
index df73580e5d..e0fe322500 100644
--- a/block/qcow2-refcount.c
+++ b/block/qcow2-refcount.c
@@ -1605,6 +1605,13 @@  static int check_refcounts_l2(BlockDriverState *bs, BdrvCheckResult *res,
                 res->corruptions++;
             }
 
+            if (has_data_file(bs)) {
+                fprintf(stderr, "ERROR compressed cluster %d with data file, "
+                        "entry=0x%" PRIx64 "\n", i, l2_entry);
+                res->corruptions++;
+                break;
+            }
+
             /* Mark cluster as used */
             nb_csectors = ((l2_entry >> s->csize_shift) &
                            s->csize_mask) + 1;
@@ -1695,11 +1702,13 @@  static int check_refcounts_l2(BlockDriverState *bs, BdrvCheckResult *res,
             }
 
             /* Mark cluster as used */
-            ret = qcow2_inc_refcounts_imrt(bs, res,
-                                           refcount_table, refcount_table_size,
-                                           offset, s->cluster_size);
-            if (ret < 0) {
-                goto fail;
+            if (!has_data_file(bs)) {
+                ret = qcow2_inc_refcounts_imrt(bs, res, refcount_table,
+                                               refcount_table_size,
+                                               offset, s->cluster_size);
+                if (ret < 0) {
+                    goto fail;
+                }
             }
             break;
         }
@@ -1884,12 +1893,16 @@  static int check_oflag_copied(BlockDriverState *bs, BdrvCheckResult *res,
 
             if (cluster_type == QCOW2_CLUSTER_NORMAL ||
                 cluster_type == QCOW2_CLUSTER_ZERO_ALLOC) {
-                ret = qcow2_get_refcount(bs,
-                                         data_offset >> s->cluster_bits,
-                                         &refcount);
-                if (ret < 0) {
-                    /* don't print message nor increment check_errors */
-                    continue;
+                if (has_data_file(bs)) {
+                    refcount = 1;
+                } else {
+                    ret = qcow2_get_refcount(bs,
+                                             data_offset >> s->cluster_bits,
+                                             &refcount);
+                    if (ret < 0) {
+                        /* don't print message nor increment check_errors */
+                        continue;
+                    }
                 }
                 if ((refcount == 1) != ((l2_entry & QCOW_OFLAG_COPIED) != 0)) {
                     fprintf(stderr, "%s OFLAG_COPIED data cluster: "
@@ -2083,6 +2096,12 @@  static int calculate_refcounts(BlockDriverState *bs, BdrvCheckResult *res,
     }
 
     /* snapshots */
+    if (has_data_file(bs) && s->nb_snapshots) {
+        fprintf(stderr, "ERROR %d snapshots in image with data file\n",
+                s->nb_snapshots);
+        res->corruptions++;
+    }
+
     for (i = 0; i < s->nb_snapshots; i++) {
         sn = s->snapshots + i;
         if (offset_into_cluster(s, sn->l1_table_offset)) {