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author | 2014-03-06 21:48:29 +0000 | |
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committer | 2014-03-07 15:56:35 -0500 | |
commit | e3377f36ca20a034dce56335dc9b89f41094d845 (patch) | |
tree | 2a2c0d898afae8176b1561a4480f454893fc24ef /sound | |
parent | xen-netback: Add stat counters for zerocopy (diff) | |
download | linux-dev-e3377f36ca20a034dce56335dc9b89f41094d845.tar.xz linux-dev-e3377f36ca20a034dce56335dc9b89f41094d845.zip |
xen-netback: Handle guests with too many frags
Xen network protocol had implicit dependency on MAX_SKB_FRAGS. Netback has to
handle guests sending up to XEN_NETBK_LEGACY_SLOTS_MAX slots. To achieve that:
- create a new skb
- map the leftover slots to its frags (no linear buffer here!)
- chain it to the previous through skb_shinfo(skb)->frag_list
- map them
- copy and coalesce the frags into a brand new one and send it to the stack
- unmap the 2 old skb's pages
It's also introduces new stat counters, which help determine how often the guest
sends a packet with more than MAX_SKB_FRAGS frags.
NOTE: if bisect brought you here, you should apply the series up until
"xen-netback: Timeout packets in RX path", otherwise malicious guests can block
other guests by not releasing their sent packets.
Signed-off-by: Zoltan Kiss <zoltan.kiss@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'sound')
0 files changed, 0 insertions, 0 deletions