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author | Paolo Bonzini <pbonzini@redhat.com> | 2011-11-29 12:42:20 +0100 |
---|---|---|
committer | Kevin Wolf <kwolf@redhat.com> | 2014-01-24 17:40:02 +0100 |
commit | c25f53b06eba1575d5d0e92a0132455c97825b83 (patch) | |
tree | cf2b0c8ed726159431608cf097f9c89d022104aa /block/raw-win32.c | |
parent | 1b7fd729559c6d3b273303aa48bc653ceef08747 (diff) | |
download | hqemu-c25f53b06eba1575d5d0e92a0132455c97825b83.zip hqemu-c25f53b06eba1575d5d0e92a0132455c97825b83.tar.gz |
raw: Probe required direct I/O alignment
Add a bs->request_alignment field that contains the required
offset/length alignment for I/O requests and fill it in the raw block
drivers. Use ioctls if possible, else see what alignment it takes for
O_DIRECT to succeed.
While at it, also expose the memory alignment requirements, which may be
(and in practice are) different from the disk alignment requirements.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Diffstat (limited to 'block/raw-win32.c')
-rw-r--r-- | block/raw-win32.c | 41 |
1 files changed, 41 insertions, 0 deletions
diff --git a/block/raw-win32.c b/block/raw-win32.c index ce314fd..beb7f23 100644 --- a/block/raw-win32.c +++ b/block/raw-win32.c @@ -202,6 +202,35 @@ static int set_sparse(int fd) NULL, 0, NULL, 0, &returned, NULL); } +static void raw_probe_alignment(BlockDriverState *bs) +{ + BDRVRawState *s = bs->opaque; + DWORD sectorsPerCluster, freeClusters, totalClusters, count; + DISK_GEOMETRY_EX dg; + BOOL status; + + if (s->type == FTYPE_CD) { + bs->request_alignment = 2048; + return; + } + if (s->type == FTYPE_HARDDISK) { + status = DeviceIoControl(s->hfile, IOCTL_DISK_GET_DRIVE_GEOMETRY_EX, + NULL, 0, &dg, sizeof(dg), &count, NULL); + if (status != 0) { + bs->request_alignment = dg.Geometry.BytesPerSector; + return; + } + /* try GetDiskFreeSpace too */ + } + + if (s->drive_path[0]) { + GetDiskFreeSpace(s->drive_path, §orsPerCluster, + &dg.Geometry.BytesPerSector, + &freeClusters, &totalClusters); + bs->request_alignment = dg.Geometry.BytesPerSector; + } +} + static void raw_parse_flags(int flags, int *access_flags, DWORD *overlapped) { assert(access_flags != NULL); @@ -269,6 +298,17 @@ static int raw_open(BlockDriverState *bs, QDict *options, int flags, } } + if (filename[0] && filename[1] == ':') { + snprintf(s->drive_path, sizeof(s->drive_path), "%c:\\", filename[0]); + } else if (filename[0] == '\\' && filename[1] == '\\') { + s->drive_path[0] = 0; + } else { + /* Relative path. */ + char buf[MAX_PATH]; + GetCurrentDirectory(MAX_PATH, buf); + snprintf(s->drive_path, sizeof(s->drive_path), "%c:\\", buf[0]); + } + s->hfile = CreateFile(filename, access_flags, FILE_SHARE_READ, NULL, OPEN_EXISTING, overlapped, NULL); @@ -293,6 +333,7 @@ static int raw_open(BlockDriverState *bs, QDict *options, int flags, s->aio = aio; } + raw_probe_alignment(bs); ret = 0; fail: qemu_opts_del(opts); |