diff options
| author | aliguori <aliguori@c046a42c-6fe2-441c-8c8c-71466251a162> | 2008-10-14 14:42:54 +0000 |
|---|---|---|
| committer | aliguori <aliguori@c046a42c-6fe2-441c-8c8c-71466251a162> | 2008-10-14 14:42:54 +0000 |
| commit | 9f7965c7e965c8b80da27048017a360b3c57c4af (patch) | |
| tree | 9a7b218b7a7b590fe926f1c282dfa0916f19092c /block-raw-win32.c | |
| parent | eeb438c1b84468e8faa7e69bec86b78b45f2347f (diff) | |
Expand cache= option and use write-through caching by default
This patch changes the cache= option to accept none, writeback, or writethough
to control the host page cache behavior. By default, writethrough caching is
now used which internally is implemented by using O_DSYNC to open the disk
images. When using -snapshot, writeback is used by default since data integrity
it not at all an issue.
cache=none has the same behavior as cache=off previously. The later syntax is
still supported by now deprecated. I also cleaned up the O_DIRECT
implementation to avoid many of the #ifdefs.
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5485 c046a42c-6fe2-441c-8c8c-71466251a162
Diffstat (limited to 'block-raw-win32.c')
| -rw-r--r-- | block-raw-win32.c | 8 |
1 files changed, 6 insertions, 2 deletions
diff --git a/block-raw-win32.c b/block-raw-win32.c index fd4a9e3a4c..892f2d1e5a 100644 --- a/block-raw-win32.c +++ b/block-raw-win32.c @@ -104,8 +104,10 @@ static int raw_open(BlockDriverState *bs, const char *filename, int flags) #else overlapped = FILE_ATTRIBUTE_NORMAL; #endif - if (flags & BDRV_O_DIRECT) + if ((flags & BDRV_O_NOCACHE)) overlapped |= FILE_FLAG_NO_BUFFERING | FILE_FLAG_WRITE_THROUGH; + else if (!(flags & BDRV_O_CACHE_WB)) + overlapped |= FILE_FLAG_WRITE_THROUGH; s->hfile = CreateFile(filename, access_flags, FILE_SHARE_READ, NULL, create_flags, overlapped, NULL); @@ -440,8 +442,10 @@ static int hdev_open(BlockDriverState *bs, const char *filename, int flags) #else overlapped = FILE_ATTRIBUTE_NORMAL; #endif - if (flags & BDRV_O_DIRECT) + if ((flags & BDRV_O_NOCACHE)) overlapped |= FILE_FLAG_NO_BUFFERING | FILE_FLAG_WRITE_THROUGH; + else if (!(flags & BDRV_O_CACHE_WB)) + overlapped |= FILE_FLAG_WRITE_THROUGH; s->hfile = CreateFile(filename, access_flags, FILE_SHARE_READ, NULL, create_flags, overlapped, NULL); |