Merge remote-tracking branch 'kwolf/tags/for-upstream' into staging
Block layer patches for 2.8.0-rc2
# gpg: Signature made Tue 29 Nov 2016 03:16:10 PM GMT
# gpg: using RSA key 0x7F09B272C88F2FD6
# gpg: Good signature from "Kevin Wolf <kwolf@redhat.com>"
# Primary key fingerprint: DC3D EB15 9A9A F95D 3D74 56FE 7F09 B272 C88F 2FD6
* kwolf/tags/for-upstream:
docs: Specify that cache-clean-interval is only supported in Linux
qcow2: Remove stale comment
qcow2: Allow 'cache-clean-interval' in Linux only
qcow2: Make qcow2_cache_table_release() work only in Linux
Message-id: 1480436227-2211-1-git-send-email-kwolf@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
diff --git a/block/qcow2-cache.c b/block/qcow2-cache.c
index 6eaefed..1d25147 100644
--- a/block/qcow2-cache.c
+++ b/block/qcow2-cache.c
@@ -22,7 +22,6 @@
* THE SOFTWARE.
*/
-/* Needed for CONFIG_MADVISE */
#include "qemu/osdep.h"
#include "block/block_int.h"
#include "qemu-common.h"
@@ -66,7 +65,8 @@
static void qcow2_cache_table_release(BlockDriverState *bs, Qcow2Cache *c,
int i, int num_tables)
{
-#if QEMU_MADV_DONTNEED != QEMU_MADV_INVALID
+/* Using MADV_DONTNEED to discard memory is a Linux-specific feature */
+#ifdef CONFIG_LINUX
BDRVQcow2State *s = bs->opaque;
void *t = qcow2_cache_get_table_addr(bs, c, i);
int align = getpagesize();
@@ -74,7 +74,7 @@
size_t offset = QEMU_ALIGN_UP((uintptr_t) t, align) - (uintptr_t) t;
size_t length = QEMU_ALIGN_DOWN(mem_size - offset, align);
if (length > 0) {
- qemu_madvise((uint8_t *) t + offset, length, QEMU_MADV_DONTNEED);
+ madvise((uint8_t *) t + offset, length, MADV_DONTNEED);
}
#endif
}
diff --git a/block/qcow2.c b/block/qcow2.c
index 7cfcd84..ed9e0f3 100644
--- a/block/qcow2.c
+++ b/block/qcow2.c
@@ -668,6 +668,14 @@
r->cache_clean_interval =
qemu_opt_get_number(opts, QCOW2_OPT_CACHE_CLEAN_INTERVAL,
s->cache_clean_interval);
+#ifndef CONFIG_LINUX
+ if (r->cache_clean_interval != 0) {
+ error_setg(errp, QCOW2_OPT_CACHE_CLEAN_INTERVAL
+ " not supported on this host");
+ ret = -EINVAL;
+ goto fail;
+ }
+#endif
if (r->cache_clean_interval > UINT_MAX) {
error_setg(errp, "Cache clean interval too big");
ret = -EINVAL;
diff --git a/docs/qcow2-cache.txt b/docs/qcow2-cache.txt
index 5bb0607..1fdd6f9 100644
--- a/docs/qcow2-cache.txt
+++ b/docs/qcow2-cache.txt
@@ -160,5 +160,6 @@
this feature.
Note that this functionality currently relies on the MADV_DONTNEED
-argument for madvise() to actually free the memory, so it is not
-useful in systems that don't follow that behavior.
+argument for madvise() to actually free the memory. This is a
+Linux-specific feature, so cache-clean-interval is not supported in
+other systems.
