From ac3d5ac277352fe6e27809286768e9f1f8aa388d Mon Sep 17 00:00:00 2001 From: Paul Durrant Date: Mon, 23 Dec 2013 09:27:17 +0000 Subject: xen-netback: fix guest-receive-side array sizes The sizes chosen for the metadata and grant_copy_op arrays on the guest receive size are wrong; - The meta array is needlessly twice the ring size, when we only ever consume a single array element per RX ring slot - The grant_copy_op array is way too small. It's sized based on a bogus assumption: that at most two copy ops will be used per ring slot. This may have been true at some point in the past but it's clear from looking at start_new_rx_buffer() that a new ring slot is only consumed if a frag would overflow the current slot (plus some other conditions) so the actual limit is MAX_SKB_FRAGS grant_copy_ops per ring slot. This patch fixes those two sizing issues and, because grant_copy_ops grows so much, it pulls it out into a separate chunk of vmalloc()ed memory. Signed-off-by: Paul Durrant Acked-by: Wei Liu Cc: Ian Campbell Cc: David Vrabel Signed-off-by: David S. Miller --- drivers/net/xen-netback/interface.c | 10 ++++++++++ 1 file changed, 10 insertions(+) (limited to 'drivers/net/xen-netback/interface.c') diff --git a/drivers/net/xen-netback/interface.c b/drivers/net/xen-netback/interface.c index 870f1fa5837..34ca4e58a43 100644 --- a/drivers/net/xen-netback/interface.c +++ b/drivers/net/xen-netback/interface.c @@ -307,6 +307,15 @@ struct xenvif *xenvif_alloc(struct device *parent, domid_t domid, SET_NETDEV_DEV(dev, parent); vif = netdev_priv(dev); + + vif->grant_copy_op = vmalloc(sizeof(struct gnttab_copy) * + MAX_GRANT_COPY_OPS); + if (vif->grant_copy_op == NULL) { + pr_warn("Could not allocate grant copy space for %s\n", name); + free_netdev(dev); + return ERR_PTR(-ENOMEM); + } + vif->domid = domid; vif->handle = handle; vif->can_sg = 1; @@ -487,6 +496,7 @@ void xenvif_free(struct xenvif *vif) unregister_netdev(vif->dev); + vfree(vif->grant_copy_op); free_netdev(vif->dev); module_put(THIS_MODULE); -- cgit v1.2.3-70-g09d2 From f35f76ee76df008131bbe01a2297de0c55ee2297 Mon Sep 17 00:00:00 2001 From: Josh Boyer Date: Sun, 5 Jan 2014 10:24:01 -0500 Subject: xen-netback: Include header for vmalloc Commit ac3d5ac27735 ("xen-netback: fix guest-receive-side array sizes") added calls to vmalloc and vfree in the interface.c file without including . This causes build failures if the -Werror=implicit-function-declaration flag is passed. Signed-off-by: Josh Boyer Acked-by: Wei Liu Signed-off-by: David S. Miller --- drivers/net/xen-netback/interface.c | 1 + 1 file changed, 1 insertion(+) (limited to 'drivers/net/xen-netback/interface.c') diff --git a/drivers/net/xen-netback/interface.c b/drivers/net/xen-netback/interface.c index 34ca4e58a43..fff8cddfed8 100644 --- a/drivers/net/xen-netback/interface.c +++ b/drivers/net/xen-netback/interface.c @@ -34,6 +34,7 @@ #include #include #include +#include #include #include -- cgit v1.2.3-70-g09d2