mptcp: protect the rx path with the msk socket spinlock
Such spinlock is currently used only to protect the 'owned'
flag inside the socket lock itself. With this patch, we extend
its scope to protect the whole msk receive path and
sk_forward_memory.
Given the above, we can always move data into the msk receive
queue (and OoO queue) from the subflow.
We leverage the previous commit, so that we need to acquire the
spinlock in the tx path only when moving fwd memory.
recvmsg() must now explicitly acquire the socket spinlock
when moving skbs out of sk_receive_queue. To reduce the number of
lock operations required we use a second rx queue and splice the
first into the latter in mptcp_lock_sock(). Additionally rmem
allocated memory is bulk-freed via release_cb()
Acked-by: Florian Westphal <fw@strlen.de>
Co-developed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h
index 4cf3550..fe2efd9 100644
--- a/net/mptcp/protocol.h
+++ b/net/mptcp/protocol.h
@@ -227,6 +227,7 @@ struct mptcp_sock {
unsigned long timer_ival;
u32 token;
int rmem_pending;
+ int rmem_released;
unsigned long flags;
bool can_ack;
bool fully_established;
@@ -238,6 +239,7 @@ struct mptcp_sock {
struct work_struct work;
struct sk_buff *ooo_last_skb;
struct rb_root out_of_order_queue;
+ struct sk_buff_head receive_queue;
struct list_head conn_list;
struct list_head rtx_queue;
struct mptcp_data_frag *first_pending;
@@ -267,6 +269,9 @@ struct mptcp_sock {
local_bh_enable(); \
} while (0)
+#define mptcp_data_lock(sk) spin_lock_bh(&(sk)->sk_lock.slock)
+#define mptcp_data_unlock(sk) spin_unlock_bh(&(sk)->sk_lock.slock)
+
#define mptcp_for_each_subflow(__msk, __subflow) \
list_for_each_entry(__subflow, &((__msk)->conn_list), node)
