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authorPaolo Bonzini <pbonzini@redhat.com>2012-06-06 00:04:55 +0200
committerKevin Wolf <kwolf@redhat.com>2012-06-15 14:03:43 +0200
commit6af4e9ead4ec9491259c9861b1b35f9abee24a66 (patch)
treee73675471adb5001272bbfcbab116da8d8acf829 /block/qcow2-cache.c
parent7cdd481cdf15d610f83e38f15c7e7979420c6ac0 (diff)
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qcow2: always operate caches in writeback mode
Writethrough does not need special-casing anymore in the qcow2 caches. The block layer adds flushes after every guest-initiated data write, and these will also flush the qcow2 caches to the OS. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Diffstat (limited to 'block/qcow2-cache.c')
-rw-r--r--block/qcow2-cache.c25
1 files changed, 2 insertions, 23 deletions
diff --git a/block/qcow2-cache.c b/block/qcow2-cache.c
index 710d4b1..2d4322a 100644
--- a/block/qcow2-cache.c
+++ b/block/qcow2-cache.c
@@ -40,11 +40,9 @@ struct Qcow2Cache {
struct Qcow2Cache* depends;
int size;
bool depends_on_flush;
- bool writethrough;
};
-Qcow2Cache *qcow2_cache_create(BlockDriverState *bs, int num_tables,
- bool writethrough)
+Qcow2Cache *qcow2_cache_create(BlockDriverState *bs, int num_tables)
{
BDRVQcowState *s = bs->opaque;
Qcow2Cache *c;
@@ -53,7 +51,6 @@ Qcow2Cache *qcow2_cache_create(BlockDriverState *bs, int num_tables,
c = g_malloc0(sizeof(*c));
c->size = num_tables;
c->entries = g_malloc0(sizeof(*c->entries) * num_tables);
- c->writethrough = writethrough;
for (i = 0; i < c->size; i++) {
c->entries[i].table = qemu_blockalign(bs, s->cluster_size);
@@ -307,12 +304,7 @@ found:
*table = NULL;
assert(c->entries[i].ref >= 0);
-
- if (c->writethrough) {
- return qcow2_cache_entry_flush(bs, c, i);
- } else {
- return 0;
- }
+ return 0;
}
void qcow2_cache_entry_mark_dirty(Qcow2Cache *c, void *table)
@@ -329,16 +321,3 @@ void qcow2_cache_entry_mark_dirty(Qcow2Cache *c, void *table)
found:
c->entries[i].dirty = true;
}
-
-bool qcow2_cache_set_writethrough(BlockDriverState *bs, Qcow2Cache *c,
- bool enable)
-{
- bool old = c->writethrough;
-
- if (!old && enable) {
- qcow2_cache_flush(bs, c);
- }
-
- c->writethrough = enable;
- return old;
-}