| Message ID | 1349876922-11907-1-git-send-email-ian.campbell@citrix.com |
|---|---|
| State | Accepted, archived |
| Delegated to: | David Miller |
| Headers | show |
On Wed, Oct 10, 2012 at 02:48:42PM +0100, Ian Campbell wrote: > An SKB paged fragment can consist of a compound page with order > 0. > However the netchannel protocol deals only in PAGE_SIZE frames. > > Handle this in netbk_gop_frag_copy and xen_netbk_count_skb_slots by > iterating over the frames which make up the page. > > Signed-off-by: Ian Campbell <ian.campbell@citrix.com> > Cc: Eric Dumazet <eric.dumazet@gmail.com> > Cc: Konrad Rzeszutek Wilk <konrad@kernel.org> Tested-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> > Cc: Sander Eikelenboom <linux@eikelenboom.it> > --- > v2: Only move to next frame if there is data remaining. > --- > drivers/net/xen-netback/netback.c | 40 ++++++++++++++++++++++++++++++++---- > 1 files changed, 35 insertions(+), 5 deletions(-) > > diff --git a/drivers/net/xen-netback/netback.c b/drivers/net/xen-netback/netback.c > index 4ebfcf3..f2d6b78 100644 > --- a/drivers/net/xen-netback/netback.c > +++ b/drivers/net/xen-netback/netback.c > @@ -335,21 +335,35 @@ unsigned int xen_netbk_count_skb_slots(struct xenvif *vif, struct sk_buff *skb) > > for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { > unsigned long size = skb_frag_size(&skb_shinfo(skb)->frags[i]); > + unsigned long offset = skb_shinfo(skb)->frags[i].page_offset; > unsigned long bytes; > + > + offset &= ~PAGE_MASK; > + > while (size > 0) { > + BUG_ON(offset >= PAGE_SIZE); > BUG_ON(copy_off > MAX_BUFFER_OFFSET); > > - if (start_new_rx_buffer(copy_off, size, 0)) { > + bytes = PAGE_SIZE - offset; > + > + if (bytes > size) > + bytes = size; > + > + if (start_new_rx_buffer(copy_off, bytes, 0)) { > count++; > copy_off = 0; > } > > - bytes = size; > if (copy_off + bytes > MAX_BUFFER_OFFSET) > bytes = MAX_BUFFER_OFFSET - copy_off; > > copy_off += bytes; > + > + offset += bytes; > size -= bytes; > + > + if (offset == PAGE_SIZE) > + offset = 0; > } > } > return count; > @@ -403,14 +417,24 @@ static void netbk_gop_frag_copy(struct xenvif *vif, struct sk_buff *skb, > unsigned long bytes; > > /* Data must not cross a page boundary. */ > - BUG_ON(size + offset > PAGE_SIZE); > + BUG_ON(size + offset > PAGE_SIZE<<compound_order(page)); > > meta = npo->meta + npo->meta_prod - 1; > > + /* Skip unused frames from start of page */ > + page += offset >> PAGE_SHIFT; > + offset &= ~PAGE_MASK; > + > while (size > 0) { > + BUG_ON(offset >= PAGE_SIZE); > BUG_ON(npo->copy_off > MAX_BUFFER_OFFSET); > > - if (start_new_rx_buffer(npo->copy_off, size, *head)) { > + bytes = PAGE_SIZE - offset; > + > + if (bytes > size) > + bytes = size; > + > + if (start_new_rx_buffer(npo->copy_off, bytes, *head)) { > /* > * Netfront requires there to be some data in the head > * buffer. > @@ -420,7 +444,6 @@ static void netbk_gop_frag_copy(struct xenvif *vif, struct sk_buff *skb, > meta = get_next_rx_buffer(vif, npo); > } > > - bytes = size; > if (npo->copy_off + bytes > MAX_BUFFER_OFFSET) > bytes = MAX_BUFFER_OFFSET - npo->copy_off; > > @@ -453,6 +476,13 @@ static void netbk_gop_frag_copy(struct xenvif *vif, struct sk_buff *skb, > offset += bytes; > size -= bytes; > > + /* Next frame */ > + if (offset == PAGE_SIZE && size) { > + BUG_ON(!PageCompound(page)); > + page++; > + offset = 0; > + } > + > /* Leave a gap for the GSO descriptor. */ > if (*head && skb_shinfo(skb)->gso_size && !vif->gso_prefix) > vif->rx.req_cons++; > -- > 1.7.2.5 > > > _______________________________________________ > Xen-devel mailing list > Xen-devel@lists.xen.org > http://lists.xen.org/xen-devel > -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
From: Ian Campbell <ian.campbell@citrix.com> Date: Wed, 10 Oct 2012 14:48:42 +0100 > An SKB paged fragment can consist of a compound page with order > 0. > However the netchannel protocol deals only in PAGE_SIZE frames. > > Handle this in netbk_gop_frag_copy and xen_netbk_count_skb_slots by > iterating over the frames which make up the page. > > Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Applied. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/net/xen-netback/netback.c b/drivers/net/xen-netback/netback.c index 4ebfcf3..f2d6b78 100644 --- a/drivers/net/xen-netback/netback.c +++ b/drivers/net/xen-netback/netback.c @@ -335,21 +335,35 @@ unsigned int xen_netbk_count_skb_slots(struct xenvif *vif, struct sk_buff *skb) for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { unsigned long size = skb_frag_size(&skb_shinfo(skb)->frags[i]); + unsigned long offset = skb_shinfo(skb)->frags[i].page_offset; unsigned long bytes; + + offset &= ~PAGE_MASK; + while (size > 0) { + BUG_ON(offset >= PAGE_SIZE); BUG_ON(copy_off > MAX_BUFFER_OFFSET); - if (start_new_rx_buffer(copy_off, size, 0)) { + bytes = PAGE_SIZE - offset; + + if (bytes > size) + bytes = size; + + if (start_new_rx_buffer(copy_off, bytes, 0)) { count++; copy_off = 0; } - bytes = size; if (copy_off + bytes > MAX_BUFFER_OFFSET) bytes = MAX_BUFFER_OFFSET - copy_off; copy_off += bytes; + + offset += bytes; size -= bytes; + + if (offset == PAGE_SIZE) + offset = 0; } } return count; @@ -403,14 +417,24 @@ static void netbk_gop_frag_copy(struct xenvif *vif, struct sk_buff *skb, unsigned long bytes; /* Data must not cross a page boundary. */ - BUG_ON(size + offset > PAGE_SIZE); + BUG_ON(size + offset > PAGE_SIZE<<compound_order(page)); meta = npo->meta + npo->meta_prod - 1; + /* Skip unused frames from start of page */ + page += offset >> PAGE_SHIFT; + offset &= ~PAGE_MASK; + while (size > 0) { + BUG_ON(offset >= PAGE_SIZE); BUG_ON(npo->copy_off > MAX_BUFFER_OFFSET); - if (start_new_rx_buffer(npo->copy_off, size, *head)) { + bytes = PAGE_SIZE - offset; + + if (bytes > size) + bytes = size; + + if (start_new_rx_buffer(npo->copy_off, bytes, *head)) { /* * Netfront requires there to be some data in the head * buffer. @@ -420,7 +444,6 @@ static void netbk_gop_frag_copy(struct xenvif *vif, struct sk_buff *skb, meta = get_next_rx_buffer(vif, npo); } - bytes = size; if (npo->copy_off + bytes > MAX_BUFFER_OFFSET) bytes = MAX_BUFFER_OFFSET - npo->copy_off; @@ -453,6 +476,13 @@ static void netbk_gop_frag_copy(struct xenvif *vif, struct sk_buff *skb, offset += bytes; size -= bytes; + /* Next frame */ + if (offset == PAGE_SIZE && size) { + BUG_ON(!PageCompound(page)); + page++; + offset = 0; + } + /* Leave a gap for the GSO descriptor. */ if (*head && skb_shinfo(skb)->gso_size && !vif->gso_prefix) vif->rx.req_cons++;
An SKB paged fragment can consist of a compound page with order > 0. However the netchannel protocol deals only in PAGE_SIZE frames. Handle this in netbk_gop_frag_copy and xen_netbk_count_skb_slots by iterating over the frames which make up the page. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Konrad Rzeszutek Wilk <konrad@kernel.org> Cc: Sander Eikelenboom <linux@eikelenboom.it> --- v2: Only move to next frame if there is data remaining. --- drivers/net/xen-netback/netback.c | 40 ++++++++++++++++++++++++++++++++---- 1 files changed, 35 insertions(+), 5 deletions(-)