Patchwork [3/3] blockdev: flip default cache mode from writethrough to writeback

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Submitter Paolo Bonzini
Date Aug. 9, 2012, 2:07 p.m.
Message ID <1344521241-22897-4-git-send-email-pbonzini@redhat.com>
Download mbox | patch
Permalink /patch/176119/
State New
Headers show

Comments

Paolo Bonzini - Aug. 9, 2012, 2:07 p.m.
Now all major device models (IDE, SCSI, virtio) can choose between
writethrough and writeback at run-time, and virtio will even revert
to writethrough if the guest is not capable of sending flushes.  So
we can change the default to writeback at last.

Tested, for lack of a better idea, with a breakpoint on bdrv_open
and all cache choices one by one.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 blockdev.c | 1 +
 1 file modificato, 1 inserzione(+)

Patch

diff --git a/blockdev.c b/blockdev.c
index 8669142..7c83baa 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -377,6 +377,7 @@  DriveInfo *drive_init(QemuOpts *opts, int default_to_scsi)
 	}
     }
 
+    bdrv_flags |= BDRV_O_CACHE_WB;
     if ((buf = qemu_opt_get(opts, "cache")) != NULL) {
         if (bdrv_parse_cache_flags(buf, &bdrv_flags) != 0) {
             error_report("invalid cache option");