From 1d422bdcb24419c7a22809e13c2c89a9fef416ac Mon Sep 17 00:00:00 2001
From: Kevin Wolf <kwolf@redhat.com>
Date: Fri, 22 Jan 2010 14:47:46 -0200
Subject: [PATCH 10/10] qcow2: Don't ignore qcow2_alloc_clusters return value

RH-Author: Kevin Wolf <kwolf@redhat.com>
Message-id: <1264171666-30186-3-git-send-email-kwolf@redhat.com>
Patchwork-id: 6550
O-Subject: [RHEL-5.5 KVM PATCH v2 10/10] qcow2: Don't ignore
	qcow2_alloc_clusters return value
Bugzilla: 537077
RH-Acked-by: Juan Quintela <quintela@redhat.com>
RH-Acked-by: Gleb Natapov <gleb@redhat.com>
RH-Acked-by: Markus Armbruster <armbru@redhat.com>

Bugzilla: 537077
Upstream status: Submitted

Now that qcow2_alloc_clusters can return error codes, we must handle them in
the callers of qcow2_alloc_clusters.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
---
 qemu/block-qcow2.c |   42 +++++++++++++++++++++++++++++++++++++-----
 1 files changed, 37 insertions(+), 5 deletions(-)

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
---
 qemu/block-qcow2.c |   42 +++++++++++++++++++++++++++++++++++++-----
 1 files changed, 37 insertions(+), 5 deletions(-)

diff --git a/qemu/block-qcow2.c b/qemu/block-qcow2.c
index 20cb9e5..6d7c89e 100644
--- a/qemu/block-qcow2.c
+++ b/qemu/block-qcow2.c
@@ -539,7 +539,7 @@ static int grow_l1_table(BlockDriverState *bs, int min_size)
     BDRVQcowState *s = bs->opaque;
     int new_l1_size, new_l1_size2, ret, i;
     uint64_t *new_l1_table;
-    uint64_t new_l1_table_offset;
+    int64_t new_l1_table_offset;
     uint8_t data[12];
 
     new_l1_size = s->l1_size;
@@ -560,6 +560,10 @@ static int grow_l1_table(BlockDriverState *bs, int min_size)
 
     /* write new table (align to cluster) */
     new_l1_table_offset = alloc_clusters(bs, new_l1_size2);
+    if (new_l1_table_offset < 0) {
+        qemu_free(new_l1_table);
+        return new_l1_table_offset;
+    }
 
     for(i = 0; i < s->l1_size; i++)
         new_l1_table[i] = cpu_to_be64(new_l1_table[i]);
@@ -693,13 +697,17 @@ static uint64_t *l2_allocate(BlockDriverState *bs, int l1_index)
     BDRVQcowState *s = bs->opaque;
     int min_index;
     uint64_t old_l2_offset;
-    uint64_t *l2_table, l2_offset;
+    uint64_t *l2_table;
+    int64_t l2_offset;
 
     old_l2_offset = s->l1_table[l1_index];
 
     /* allocate a new l2 entry */
 
     l2_offset = alloc_clusters(bs, s->l2_size * sizeof(uint64_t));
+    if (l2_offset < 0) {
+        return NULL;
+    }
 
     /* update the L1 entry */
 
@@ -967,7 +975,8 @@ static uint64_t alloc_compressed_cluster_offset(BlockDriverState *bs,
 {
     BDRVQcowState *s = bs->opaque;
     int l2_index, ret;
-    uint64_t l2_offset, *l2_table, cluster_offset;
+    uint64_t l2_offset, *l2_table;
+    int64_t cluster_offset;
     int nb_csectors;
 
     ret = get_cluster_table(bs, offset, &l2_table, &l2_offset, &l2_index);
@@ -983,6 +992,10 @@ static uint64_t alloc_compressed_cluster_offset(BlockDriverState *bs,
         free_any_clusters(bs, cluster_offset, 1);
 
     cluster_offset = alloc_bytes(bs, compressed_size);
+    if (cluster_offset < 0) {
+        return 0;
+    }
+
     nb_csectors = ((cluster_offset + compressed_size - 1) >> 9) -
                   (cluster_offset >> 9);
 
@@ -1122,7 +1135,8 @@ static int alloc_cluster_offset(BlockDriverState *bs, uint64_t offset,
 {
     BDRVQcowState *s = bs->opaque;
     int l2_index, ret;
-    uint64_t l2_offset, *l2_table, cluster_offset;
+    uint64_t l2_offset, *l2_table;
+    int64_t cluster_offset;
     int nb_clusters, i = 0;
 
     ret = get_cluster_table(bs, offset, &l2_table, &l2_offset, &l2_index);
@@ -1176,6 +1190,9 @@ static int alloc_cluster_offset(BlockDriverState *bs, uint64_t offset,
     /* allocate a new cluster */
 
     cluster_offset = alloc_clusters(bs, nb_clusters * s->cluster_size);
+    if (cluster_offset < 0) {
+        return cluster_offset;
+    }
 
     /* save info needed for meta data update */
     m->offset = offset;
@@ -2200,6 +2217,9 @@ static int qcow_write_snapshots(BlockDriverState *bs)
 
     snapshots_offset = alloc_clusters(bs, snapshots_size);
     offset = snapshots_offset;
+    if (offset < 0) {
+        return offset;
+    }
 
     for(i = 0; i < s->nb_snapshots; i++) {
         sn = s->snapshots + i;
@@ -2297,6 +2317,7 @@ static int qcow_snapshot_create(BlockDriverState *bs,
     QCowSnapshot *snapshots1, sn1, *sn = &sn1;
     int i, ret;
     uint64_t *l1_table = NULL;
+    int64_t l1_table_offset;
 
     memset(sn, 0, sizeof(*sn));
 
@@ -2325,7 +2346,12 @@ static int qcow_snapshot_create(BlockDriverState *bs,
         goto fail;
 
     /* create the L1 table of the snapshot */
-    sn->l1_table_offset = alloc_clusters(bs, s->l1_size * sizeof(uint64_t));
+    l1_table_offset = alloc_clusters(bs, s->l1_size * sizeof(uint64_t));
+    if (l1_table_offset < 0) {
+        goto fail;
+    }
+
+    sn->l1_table_offset = l1_table_offset;
     sn->l1_size = s->l1_size;
 
     l1_table = qemu_malloc(s->l1_size * sizeof(uint64_t));
@@ -2601,6 +2627,9 @@ static int64_t alloc_bytes(BlockDriverState *bs, int size)
     assert(size > 0 && size <= s->cluster_size);
     if (s->free_byte_offset == 0) {
         s->free_byte_offset = alloc_clusters(bs, s->cluster_size);
+        if (s->free_byte_offset < 0) {
+            return s->free_byte_offset;
+        }
     }
  redo:
     free_in_cluster = s->cluster_size -
@@ -2616,6 +2645,9 @@ static int64_t alloc_bytes(BlockDriverState *bs, int size)
             update_cluster_refcount(bs, offset >> s->cluster_bits, 1);
     } else {
         offset = alloc_clusters(bs, s->cluster_size);
+        if (offset < 0) {
+            return offset;
+        }
         cluster_offset = s->free_byte_offset & ~(s->cluster_size - 1);
         if ((cluster_offset + s->cluster_size) == offset) {
             /* we are lucky: contiguous data */
-- 
1.6.3.rc4.29.g8146