AuxXxilium/linux_dsm_epyc7002
1
0
Fork 0
mirror of https://github.com/AuxXxilium/linux_dsm_epyc7002.git synced 2024-11-24 04:20:53 +07:00
Code Issues Actions Packages Projects Releases Wiki Activity

Drivers: hv: fcopy: restore correct transfer length

Browse Source 
Till recently the expected length of bytes read by the
daemon did depend on the context. It was either hv_start_fcopy or
hv_do_fcopy. The daemon had a buffer size of two pages, which was much
larger than needed.

Now the expected length of bytes read by the
daemon changed slightly. For START_FILE_COPY it is still the size of
hv_start_fcopy.  But for WRITE_TO_FILE and the other operations it is as
large as the buffer that arrived via vmbus. In case of WRITE_TO_FILE
that is slightly larger than a struct hv_do_fcopy. Since the buffer in
the daemon was still larger everything was fine.

Currently, the daemon reads only what is actually needed.
The new buffer layout is as large as a struct hv_do_fcopy, for the
WRITE_TO_FILE operation. Since the kernel expects a slightly larger
size, hvt_op_read will return -EINVAL because the daemon will read
slightly less than expected. Address this by restoring the expected
buffer size in case of WRITE_TO_FILE.

Fixes: 'c7e490fc23eb ("Drivers: hv: fcopy: convert to hv_utils_transport")'
Fixes: '3f2baa8a7d2e ("Tools: hv: update buffer handling in hv_fcopy_daemon")'

Signed-off-by: Olaf Hering <olaf@aepfle.de>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Olaf Hering 2017-09-21 23:41:48 -07:00 committed by Greg Kroah-Hartman
parent 33c150c2ee
commit 549e658a09
1 changed files with 4 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
drivers/hv/hv_fcopy.c
View File

@ -170,6 +170,10 @@ static void fcopy_send_data(struct work_struct *dummy)
out_src = smsg_out;
break;
case WRITE_TO_FILE:
out_src = fcopy_transaction.fcopy_msg;
out_len = sizeof(struct hv_do_fcopy);
break;
default:
out_src = fcopy_transaction.fcopy_msg;
out_len = fcopy_transaction.recv_len;