* [Qemu-devel] [PATCH v2 1/6] qcow2: Use negated overflow check mask
2013-10-10 9:09 [Qemu-devel] [PATCH v2 0/6] Configure metadata overlap checks at runtime Max Reitz
@ 2013-10-10 9:09 ` Max Reitz
2013-10-10 9:09 ` [Qemu-devel] [PATCH v2 2/6] qcow2: Make overlap check mask variable Max Reitz
` (5 subsequent siblings)
6 siblings, 0 replies; 8+ messages in thread
From: Max Reitz @ 2013-10-10 9:09 UTC (permalink / raw)
To: qemu-devel; +Cc: Kevin Wolf, Stefan Hajnoczi, Max Reitz
In qcow2_check_metadata_overlap and qcow2_pre_write_overlap_check,
change the parameter signifying the checks to perform from its current
positive form to a negative one, i.e., it will no longer explicitly
specify every check to perform but rather a mask of checks not to
perform.
Signed-off-by: Max Reitz <mreitz@redhat.com>
---
block/qcow2-cache.c | 8 +++-----
block/qcow2-cluster.c | 16 +++++++---------
block/qcow2-refcount.c | 22 ++++++++++------------
block/qcow2-snapshot.c | 12 +++++-------
block/qcow2.c | 5 ++---
block/qcow2.h | 4 ++--
6 files changed, 29 insertions(+), 38 deletions(-)
diff --git a/block/qcow2-cache.c b/block/qcow2-cache.c
index 40a5a3f..8ecbb5b 100644
--- a/block/qcow2-cache.c
+++ b/block/qcow2-cache.c
@@ -115,15 +115,13 @@ static int qcow2_cache_entry_flush(BlockDriverState *bs, Qcow2Cache *c, int i)
}
if (c == s->refcount_block_cache) {
- ret = qcow2_pre_write_overlap_check(bs,
- QCOW2_OL_DEFAULT & ~QCOW2_OL_REFCOUNT_BLOCK,
+ ret = qcow2_pre_write_overlap_check(bs, QCOW2_OL_REFCOUNT_BLOCK,
c->entries[i].offset, s->cluster_size);
} else if (c == s->l2_table_cache) {
- ret = qcow2_pre_write_overlap_check(bs,
- QCOW2_OL_DEFAULT & ~QCOW2_OL_ACTIVE_L2,
+ ret = qcow2_pre_write_overlap_check(bs, QCOW2_OL_ACTIVE_L2,
c->entries[i].offset, s->cluster_size);
} else {
- ret = qcow2_pre_write_overlap_check(bs, QCOW2_OL_DEFAULT,
+ ret = qcow2_pre_write_overlap_check(bs, 0,
c->entries[i].offset, s->cluster_size);
}
diff --git a/block/qcow2-cluster.c b/block/qcow2-cluster.c
index 0fd26bb..0348b97 100644
--- a/block/qcow2-cluster.c
+++ b/block/qcow2-cluster.c
@@ -83,8 +83,8 @@ int qcow2_grow_l1_table(BlockDriverState *bs, uint64_t min_size,
/* the L1 position has not yet been updated, so these clusters must
* indeed be completely free */
- ret = qcow2_pre_write_overlap_check(bs, QCOW2_OL_DEFAULT,
- new_l1_table_offset, new_l1_size2);
+ ret = qcow2_pre_write_overlap_check(bs, 0, new_l1_table_offset,
+ new_l1_size2);
if (ret < 0) {
goto fail;
}
@@ -160,8 +160,7 @@ int qcow2_write_l1_entry(BlockDriverState *bs, int l1_index)
buf[i] = cpu_to_be64(s->l1_table[l1_start_index + i]);
}
- ret = qcow2_pre_write_overlap_check(bs,
- QCOW2_OL_DEFAULT & ~QCOW2_OL_ACTIVE_L1,
+ ret = qcow2_pre_write_overlap_check(bs, QCOW2_OL_ACTIVE_L1,
s->l1_table_offset + 8 * l1_start_index, sizeof(buf));
if (ret < 0) {
return ret;
@@ -396,7 +395,7 @@ static int coroutine_fn copy_sectors(BlockDriverState *bs,
&s->aes_encrypt_key);
}
- ret = qcow2_pre_write_overlap_check(bs, QCOW2_OL_DEFAULT,
+ ret = qcow2_pre_write_overlap_check(bs, 0,
cluster_offset + n_start * BDRV_SECTOR_SIZE, n * BDRV_SECTOR_SIZE);
if (ret < 0) {
goto out;
@@ -1604,8 +1603,7 @@ static int expand_zero_clusters_in_l1(BlockDriverState *bs, uint64_t *l1_table,
}
}
- ret = qcow2_pre_write_overlap_check(bs, QCOW2_OL_DEFAULT,
- offset, s->cluster_size);
+ ret = qcow2_pre_write_overlap_check(bs, 0, offset, s->cluster_size);
if (ret < 0) {
if (!preallocated) {
qcow2_free_clusters(bs, offset, s->cluster_size,
@@ -1661,8 +1659,8 @@ static int expand_zero_clusters_in_l1(BlockDriverState *bs, uint64_t *l1_table,
}
} else {
if (l2_dirty) {
- ret = qcow2_pre_write_overlap_check(bs, QCOW2_OL_DEFAULT &
- ~(QCOW2_OL_INACTIVE_L2 | QCOW2_OL_ACTIVE_L2), l2_offset,
+ ret = qcow2_pre_write_overlap_check(bs,
+ QCOW2_OL_INACTIVE_L2 | QCOW2_OL_ACTIVE_L2, l2_offset,
s->cluster_size);
if (ret < 0) {
goto fail;
diff --git a/block/qcow2-refcount.c b/block/qcow2-refcount.c
index 4ef6899..988644a 100644
--- a/block/qcow2-refcount.c
+++ b/block/qcow2-refcount.c
@@ -1311,9 +1311,8 @@ static int check_oflag_copied(BlockDriverState *bs, BdrvCheckResult *res,
}
if (l2_dirty) {
- ret = qcow2_pre_write_overlap_check(bs,
- QCOW2_OL_DEFAULT & ~QCOW2_OL_ACTIVE_L2, l2_offset,
- s->cluster_size);
+ ret = qcow2_pre_write_overlap_check(bs, QCOW2_OL_ACTIVE_L2,
+ l2_offset, s->cluster_size);
if (ret < 0) {
fprintf(stderr, "ERROR: Could not write L2 table; metadata "
"overlap check failed: %s\n", strerror(-ret));
@@ -1354,8 +1353,7 @@ static int write_reftable_entry(BlockDriverState *bs, int rt_index)
buf[i] = cpu_to_be64(s->refcount_table[rt_start_index + i]);
}
- ret = qcow2_pre_write_overlap_check(bs,
- QCOW2_OL_DEFAULT & ~QCOW2_OL_REFCOUNT_TABLE,
+ ret = qcow2_pre_write_overlap_check(bs, QCOW2_OL_REFCOUNT_TABLE,
s->refcount_table_offset + rt_start_index * sizeof(uint64_t),
sizeof(buf));
if (ret < 0) {
@@ -1406,8 +1404,7 @@ static int64_t realloc_refcount_block(BlockDriverState *bs, int reftable_index,
/* new block has not yet been entered into refcount table, therefore it is
* no refcount block yet (regarding this check) */
- ret = qcow2_pre_write_overlap_check(bs, QCOW2_OL_DEFAULT, new_offset,
- s->cluster_size);
+ ret = qcow2_pre_write_overlap_check(bs, 0, new_offset, s->cluster_size);
if (ret < 0) {
fprintf(stderr, "Could not write refcount block; metadata overlap "
"check failed: %s\n", strerror(-ret));
@@ -1639,8 +1636,8 @@ fail:
* looking for overlaps with important metadata sections (L1/L2 tables etc.),
* i.e. a sanity check without relying on the refcount tables.
*
- * The chk parameter specifies exactly what checks to perform (being a bitmask
- * of QCow2MetadataOverlap values).
+ * The ign parameter specifies what checks not to perform (being a bitmask of
+ * QCow2MetadataOverlap values), i.e., what sections to ignore.
*
* Returns:
* - 0 if writing to this offset will not affect the mentioned metadata
@@ -1648,10 +1645,11 @@ fail:
* - a negative value (-errno) indicating an error while performing a check,
* e.g. when bdrv_read failed on QCOW2_OL_INACTIVE_L2
*/
-int qcow2_check_metadata_overlap(BlockDriverState *bs, int chk, int64_t offset,
+int qcow2_check_metadata_overlap(BlockDriverState *bs, int ign, int64_t offset,
int64_t size)
{
BDRVQcowState *s = bs->opaque;
+ int chk = QCOW2_OL_DEFAULT & ~ign;
int i, j;
if (!size) {
@@ -1767,10 +1765,10 @@ static const char *metadata_ol_names[] = {
* Returns 0 if there were neither overlaps nor errors while checking for
* overlaps; or a negative value (-errno) on error.
*/
-int qcow2_pre_write_overlap_check(BlockDriverState *bs, int chk, int64_t offset,
+int qcow2_pre_write_overlap_check(BlockDriverState *bs, int ign, int64_t offset,
int64_t size)
{
- int ret = qcow2_check_metadata_overlap(bs, chk, offset, size);
+ int ret = qcow2_check_metadata_overlap(bs, ign, offset, size);
if (ret < 0) {
return ret;
diff --git a/block/qcow2-snapshot.c b/block/qcow2-snapshot.c
index 884b06d..3529c68 100644
--- a/block/qcow2-snapshot.c
+++ b/block/qcow2-snapshot.c
@@ -192,8 +192,7 @@ static int qcow2_write_snapshots(BlockDriverState *bs)
/* The snapshot list position has not yet been updated, so these clusters
* must indeed be completely free */
- ret = qcow2_pre_write_overlap_check(bs, QCOW2_OL_DEFAULT, offset,
- snapshots_size);
+ ret = qcow2_pre_write_overlap_check(bs, 0, offset, snapshots_size);
if (ret < 0) {
goto fail;
}
@@ -395,8 +394,8 @@ int qcow2_snapshot_create(BlockDriverState *bs, QEMUSnapshotInfo *sn_info)
l1_table[i] = cpu_to_be64(s->l1_table[i]);
}
- ret = qcow2_pre_write_overlap_check(bs, QCOW2_OL_DEFAULT,
- sn->l1_table_offset, s->l1_size * sizeof(uint64_t));
+ ret = qcow2_pre_write_overlap_check(bs, 0, sn->l1_table_offset,
+ s->l1_size * sizeof(uint64_t));
if (ret < 0) {
goto fail;
}
@@ -521,9 +520,8 @@ int qcow2_snapshot_goto(BlockDriverState *bs, const char *snapshot_id)
goto fail;
}
- ret = qcow2_pre_write_overlap_check(bs,
- QCOW2_OL_DEFAULT & ~QCOW2_OL_ACTIVE_L1,
- s->l1_table_offset, cur_l1_bytes);
+ ret = qcow2_pre_write_overlap_check(bs, QCOW2_OL_ACTIVE_L1,
+ s->l1_table_offset, cur_l1_bytes);
if (ret < 0) {
goto fail;
}
diff --git a/block/qcow2.c b/block/qcow2.c
index b2489fb..28dc560 100644
--- a/block/qcow2.c
+++ b/block/qcow2.c
@@ -965,7 +965,7 @@ static coroutine_fn int qcow2_co_writev(BlockDriverState *bs,
cur_nr_sectors * 512);
}
- ret = qcow2_pre_write_overlap_check(bs, QCOW2_OL_DEFAULT,
+ ret = qcow2_pre_write_overlap_check(bs, 0,
cluster_offset + index_in_cluster * BDRV_SECTOR_SIZE,
cur_nr_sectors * BDRV_SECTOR_SIZE);
if (ret < 0) {
@@ -1751,8 +1751,7 @@ static int qcow2_write_compressed(BlockDriverState *bs, int64_t sector_num,
}
cluster_offset &= s->cluster_offset_mask;
- ret = qcow2_pre_write_overlap_check(bs, QCOW2_OL_DEFAULT,
- cluster_offset, out_len);
+ ret = qcow2_pre_write_overlap_check(bs, 0, cluster_offset, out_len);
if (ret < 0) {
goto fail;
}
diff --git a/block/qcow2.h b/block/qcow2.h
index 455e38d..8692011 100644
--- a/block/qcow2.h
+++ b/block/qcow2.h
@@ -433,9 +433,9 @@ int qcow2_check_refcounts(BlockDriverState *bs, BdrvCheckResult *res,
void qcow2_process_discards(BlockDriverState *bs, int ret);
-int qcow2_check_metadata_overlap(BlockDriverState *bs, int chk, int64_t offset,
+int qcow2_check_metadata_overlap(BlockDriverState *bs, int ign, int64_t offset,
int64_t size);
-int qcow2_pre_write_overlap_check(BlockDriverState *bs, int chk, int64_t offset,
+int qcow2_pre_write_overlap_check(BlockDriverState *bs, int ign, int64_t offset,
int64_t size);
/* qcow2-cluster.c functions */
--
1.8.3.1
^ permalink raw reply related [flat|nested] 8+ messages in thread* [Qemu-devel] [PATCH v2 3/6] qcow2: Add overlap-check options
2013-10-10 9:09 [Qemu-devel] [PATCH v2 0/6] Configure metadata overlap checks at runtime Max Reitz
2013-10-10 9:09 ` [Qemu-devel] [PATCH v2 1/6] qcow2: Use negated overflow check mask Max Reitz
2013-10-10 9:09 ` [Qemu-devel] [PATCH v2 2/6] qcow2: Make overlap check mask variable Max Reitz
@ 2013-10-10 9:09 ` Max Reitz
2013-10-10 9:09 ` [Qemu-devel] [PATCH v2 4/6] qcow2: Array assigning options to OL check bits Max Reitz
` (3 subsequent siblings)
6 siblings, 0 replies; 8+ messages in thread
From: Max Reitz @ 2013-10-10 9:09 UTC (permalink / raw)
To: qemu-devel; +Cc: Kevin Wolf, Stefan Hajnoczi, Max Reitz
Add runtime options to tune the overlap checks to be performed before
write accesses.
Signed-off-by: Max Reitz <mreitz@redhat.com>
---
block/qcow2.c | 46 ++++++++++++++++++++++++++++++++++++++++++++++
block/qcow2.h | 9 +++++++++
2 files changed, 55 insertions(+)
diff --git a/block/qcow2.c b/block/qcow2.c
index 199ebf2..1e29bc8 100644
--- a/block/qcow2.c
+++ b/block/qcow2.c
@@ -354,6 +354,52 @@ static QemuOptsList qcow2_runtime_opts = {
.type = QEMU_OPT_BOOL,
.help = "Generate discard requests when other clusters are freed",
},
+ {
+ .name = QCOW2_OPT_OVERLAP,
+ .type = QEMU_OPT_STRING,
+ .help = "Selects which overlap checks to perform from a range of "
+ "templates (none, constant, cached, all)",
+ },
+ {
+ .name = QCOW2_OPT_OVERLAP_MAIN_HEADER,
+ .type = QEMU_OPT_BOOL,
+ .help = "Check for unintended writes into the main qcow2 header",
+ },
+ {
+ .name = QCOW2_OPT_OVERLAP_ACTIVE_L1,
+ .type = QEMU_OPT_BOOL,
+ .help = "Check for unintended writes into the active L1 table",
+ },
+ {
+ .name = QCOW2_OPT_OVERLAP_ACTIVE_L2,
+ .type = QEMU_OPT_BOOL,
+ .help = "Check for unintended writes into an active L2 table",
+ },
+ {
+ .name = QCOW2_OPT_OVERLAP_REFCOUNT_TABLE,
+ .type = QEMU_OPT_BOOL,
+ .help = "Check for unintended writes into the refcount table",
+ },
+ {
+ .name = QCOW2_OPT_OVERLAP_REFCOUNT_BLOCK,
+ .type = QEMU_OPT_BOOL,
+ .help = "Check for unintended writes into a refcount block",
+ },
+ {
+ .name = QCOW2_OPT_OVERLAP_SNAPSHOT_TABLE,
+ .type = QEMU_OPT_BOOL,
+ .help = "Check for unintended writes into the snapshot table",
+ },
+ {
+ .name = QCOW2_OPT_OVERLAP_INACTIVE_L1,
+ .type = QEMU_OPT_BOOL,
+ .help = "Check for unintended writes into an inactive L1 table",
+ },
+ {
+ .name = QCOW2_OPT_OVERLAP_INACTIVE_L2,
+ .type = QEMU_OPT_BOOL,
+ .help = "Check for unintended writes into an inactive L2 table",
+ },
{ /* end of list */ }
},
};
diff --git a/block/qcow2.h b/block/qcow2.h
index 6c85bb9..28ccc4a 100644
--- a/block/qcow2.h
+++ b/block/qcow2.h
@@ -63,6 +63,15 @@
#define QCOW2_OPT_DISCARD_REQUEST "pass-discard-request"
#define QCOW2_OPT_DISCARD_SNAPSHOT "pass-discard-snapshot"
#define QCOW2_OPT_DISCARD_OTHER "pass-discard-other"
+#define QCOW2_OPT_OVERLAP "overlap-check"
+#define QCOW2_OPT_OVERLAP_MAIN_HEADER "overlap-check.main-header"
+#define QCOW2_OPT_OVERLAP_ACTIVE_L1 "overlap-check.active-l1"
+#define QCOW2_OPT_OVERLAP_ACTIVE_L2 "overlap-check.active-l2"
+#define QCOW2_OPT_OVERLAP_REFCOUNT_TABLE "overlap-check.refcount-table"
+#define QCOW2_OPT_OVERLAP_REFCOUNT_BLOCK "overlap-check.refcount-block"
+#define QCOW2_OPT_OVERLAP_SNAPSHOT_TABLE "overlap-check.snapshot-table"
+#define QCOW2_OPT_OVERLAP_INACTIVE_L1 "overlap-check.inactive-l1"
+#define QCOW2_OPT_OVERLAP_INACTIVE_L2 "overlap-check.inactive-l2"
typedef struct QCowHeader {
uint32_t magic;
--
1.8.3.1
^ permalink raw reply related [flat|nested] 8+ messages in thread