From: Chen Hanxiao <chenhanxiao@gmail.com>

This patch adds support for getting the usage of
windows driver path.
The usage of fs stored as used_bytes and total_bytes.

Cc: Michael Roth <mdroth@linux.vnet.ibm.com>
Signed-off-by: Chen Hanxiao <chenhanxiao@gmail.com>
---
v2:
  unpack usage as used-bytes and total-bytes

 qga/commands-win32.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/qga/commands-win32.c b/qga/commands-win32.c
index 2d48394748..eff26c177e 100644
--- a/qga/commands-win32.c
+++ b/qga/commands-win32.c
@@ -670,6 +670,7 @@ static GuestFilesystemInfo *build_guest_fsinfo(char *guid, Error **errp)
     char fs_name[32];
     char vol_info[MAX_PATH+1];
     size_t len;
+    uint64_t i64FreeBytesToCaller, i64TotalBytes, i64FreeBytes;
     GuestFilesystemInfo *fs = NULL;
 
     GetVolumePathNamesForVolumeName(guid, (LPCH)&mnt, 0, &info_size);
@@ -699,10 +700,21 @@ static GuestFilesystemInfo *build_guest_fsinfo(char *guid, Error **errp)
     fs_name[sizeof(fs_name) - 1] = 0;
     fs = g_malloc(sizeof(*fs));
     fs->name = g_strdup(guid);
+    fs->has_total_bytes = false;
+    fs->has_used_bytes = false;
     if (len == 0) {
         fs->mountpoint = g_strdup("System Reserved");
     } else {
         fs->mountpoint = g_strndup(mnt_point, len);
+        if (GetDiskFreeSpaceEx(fs->mountpoint,
+                               (PULARGE_INTEGER) & i64FreeBytesToCaller,
+                               (PULARGE_INTEGER) & i64TotalBytes,
+                               (PULARGE_INTEGER) & i64FreeBytes)) {
+            fs->used_bytes = i64TotalBytes - i64FreeBytes;
+            fs->total_bytes = i64TotalBytes;
+            fs->has_total_bytes = true;
+            fs->has_used_bytes = true;
+        }
     }
     fs->type = g_strdup(fs_name);
     fs->disk = build_guest_disk_info(guid, errp);
-- 
2.17.0

On 06/01/2018 11:57 AM, Chen Hanxiao wrote:
> From: Chen Hanxiao <chenhanxiao@gmail.com>
> 
> This patch adds support for getting the usage of
> windows driver path.
> The usage of fs stored as used_bytes and total_bytes.
> 
> Cc: Michael Roth <mdroth@linux.vnet.ibm.com>
> Signed-off-by: Chen Hanxiao <chenhanxiao@gmail.com>
> ---
> v2:
>    unpack usage as used-bytes and total-bytes
> 

> @@ -699,10 +700,21 @@ static GuestFilesystemInfo *build_guest_fsinfo(char *guid, Error **errp)
>       fs_name[sizeof(fs_name) - 1] = 0;
>       fs = g_malloc(sizeof(*fs));
>       fs->name = g_strdup(guid);
> +    fs->has_total_bytes = false;
> +    fs->has_used_bytes = false;

Dead assignments.

>       if (len == 0) {
>           fs->mountpoint = g_strdup("System Reserved");
>       } else {
>           fs->mountpoint = g_strndup(mnt_point, len);
> +        if (GetDiskFreeSpaceEx(fs->mountpoint,
> +                               (PULARGE_INTEGER) & i64FreeBytesToCaller,
> +                               (PULARGE_INTEGER) & i64TotalBytes,
> +                               (PULARGE_INTEGER) & i64FreeBytes)) {
> +            fs->used_bytes = i64TotalBytes - i64FreeBytes;
> +            fs->total_bytes = i64TotalBytes;
> +            fs->has_total_bytes = true;
> +            fs->has_used_bytes = true;
> +        }

I'm less familiar with Windows API, so I won't give this R-b. But now 
that I read this patch, I do have a question: since both statvfs() and 
GetDiskFreeSpaceEx() give you free bytes rather than used bytes, and you 
had to perform a subtraction to report 'used-bytes' over QGA, would it 
make any more sense to instead report 'free-bytes' over QGA for less 
subtraction work on your end and so that the QGA interface is more 
similar to existing interfaces?

-- 
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3266
Virtualization:  qemu.org | libvirt.org

At 2018-06-02 01:15:14, "Eric Blake" <eblake@redhat.com> wrote:
>On 06/01/2018 11:57 AM, Chen Hanxiao wrote:
>> From: Chen Hanxiao <chenhanxiao@gmail.com>
...
>>           fs->mountpoint = g_strdup("System Reserved");
>>       } else {
>>           fs->mountpoint = g_strndup(mnt_point, len);
>> +        if (GetDiskFreeSpaceEx(fs->mountpoint,
>> +                               (PULARGE_INTEGER) & i64FreeBytesToCaller,
>> +                               (PULARGE_INTEGER) & i64TotalBytes,
>> +                               (PULARGE_INTEGER) & i64FreeBytes)) {
>> +            fs->used_bytes = i64TotalBytes - i64FreeBytes;
>> +            fs->total_bytes = i64TotalBytes;
>> +            fs->has_total_bytes = true;
>> +            fs->has_used_bytes = true;
>> +        }
>
>I'm less familiar with Windows API, so I won't give this R-b. But now 
>that I read this patch, I do have a question: since both statvfs() and 
>GetDiskFreeSpaceEx() give you free bytes rather than used bytes, and you 
>had to perform a subtraction to report 'used-bytes' over QGA, would it 
>make any more sense to instead report 'free-bytes' over QGA for less 
>subtraction work on your end and so that the QGA interface is more 
>similar to existing interfaces?
>


All build-in tools report used-bytes for linux and windows.

For windows, GetDiskFreeSpaceEx would tell total and free bytes,
used bytes is  total - free,  which is exactly same
from the view of disk properties.

But for linux, df(1) do some calculation for showing used-bytes and free-bytes.

df(1) takes f_blocks - f_bfree for 'Used' ,
which take 'Used' + 'Available'(f_bavail)  for non-root total, 
which is different from 'Size'(f_blocks);
Then calculate  'Use%' by Used / non-root-total.

If we want get what df(3) outputs, we must report more members of struct statvfs  from STATVFS(3) ,
which windows does not need it.
And client had to do some calculation with if-else dealing with data from windows/linux.

Customs usually take 'Use%' to monitor their disks,
so I think we should report nums that can easily get the right percentage of usage from it,
for both linux and windows.

Regards,
- Chen