Re: [[Xen-devel] [PATCH net-next v3] xen-netfront: clean up code in xennet_release_rx_bufs

On 23/01/14 01:36, Annie Li wrote:

From: Annie Li <redacted>

This patch removes grant transfer code from netfront, and improves ending
grant acess mechanism since gnttab_end_foreign_access_ref may fail when
the grant entry is currently used for reading or writing.

* release grant reference and skb for tx/rx path, use get_page/put_page to
ensure page is released when grant access is completed successfully.
* change corresponding code in xen-blkfront/xen-tpmfront/xen-pcifront because
of code change for put_page in gnttab_end_foreign_access.
* clean up grant transfer code kept from old netfront(2.6.18) which grants
pages for access/map and transfer. But grant transfer is deprecated in current
netfront, so remove corresponding release code for transfer.

V3: Changes as suggestion from David Vrabel, ensure pages are not freed untill
grant acess is ended.

V2: improve patch comments.
Signed-off-by: Annie Li <redacted>
---
 drivers/block/xen-blkfront.c    |   25 ++++++++---
 drivers/char/tpm/xen-tpmfront.c |    7 +++-
 drivers/net/xen-netfront.c      |   93 ++++++++++++--------------------------
 drivers/pci/xen-pcifront.c      |    7 +++-
 drivers/xen/grant-table.c       |    4 +-
 5 files changed, 63 insertions(+), 73 deletions(-)

I don't understand why you've made all these unnecessary changes to the
other frontends and grant-table.c.

The xen-netfront.c changes are fine on their own.

David