net: Unmap fragment page once iterator is done

Callers of skb_seq_read() are currently forced to call skb_abort_seq_read()
even when consuming all the data because the last call to skb_seq_read (the
one that returns 0 to indicate the end) fails to unmap the last fragment page.

With this patch callers will be allowed to traverse the SKB data by calling
skb_prepare_seq_read() once and repeatedly calling skb_seq_read() as originally
intended (and documented in the original commit 677e90eda), that is, only call
skb_abort_seq_read() if the sequential read is actually aborted.

Signed-off-by: Wedson Almeida Filho <wedsonaf@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Wedson Almeida Filho 2013-06-23 23:33:48 -07:00 committed by David S. Miller
parent 7e2f934dc5
commit aeb193ea6c
3 changed files with 6 additions and 3 deletions

View File

@ -906,7 +906,6 @@ int iscsi_tcp_recv_skb(struct iscsi_conn *conn, struct sk_buff *skb,
ISCSI_DBG_TCP(conn, "no more data avail. Consumed %d\n",
consumed);
*status = ISCSI_TCP_SKB_DONE;
skb_abort_seq_read(&seq);
goto skb_done;
}
BUG_ON(segment->copied >= segment->size);

View File

@ -473,7 +473,6 @@ __be32 batadv_skb_crc32(struct sk_buff *skb, u8 *payload_ptr)
crc = crc32c(crc, data, len);
consumed += len;
}
skb_abort_seq_read(&st);
return htonl(crc);
}

View File

@ -2541,8 +2541,13 @@ unsigned int skb_seq_read(unsigned int consumed, const u8 **data,
unsigned int block_limit, abs_offset = consumed + st->lower_offset;
skb_frag_t *frag;
if (unlikely(abs_offset >= st->upper_offset))
if (unlikely(abs_offset >= st->upper_offset)) {
if (st->frag_data) {
kunmap_atomic(st->frag_data);
st->frag_data = NULL;
}
return 0;
}
next_skb:
block_limit = skb_headlen(st->cur_skb) + st->stepped_offset;