> -----Original Message-----
> From: Boris Pismenny <bor...@mellanox.com>
> Sent: Tuesday, February 26, 2019 7:43 PM
> To: Vakul Garg <vakul.g...@nxp.com>; Aviad Yehezkel
> <avia...@mellanox.com>; davejwat...@fb.com;
> john.fastab...@gmail.com; dan...@iogearbox.net; netdev@vger.kernel.org
> Cc: Eran Ben Elisha <era...@mellanox.com>
> Subject: Re: [PATCH net 2/4] tls: Fix write space handling
>
>
>
> On 2/26/2019 2:49 PM, Vakul Garg wrote:
> >
> >
> >> -----Original Message-----
> >> From: Boris Pismenny <bor...@mellanox.com>
> >> Sent: Tuesday, February 26, 2019 5:43 PM
> >> To: avia...@mellanox.com; davejwat...@fb.com;
> >> john.fastab...@gmail.com; dan...@iogearbox.net; Vakul Garg
> >> <vakul.g...@nxp.com>; netdev@vger.kernel.org
> >> Cc: era...@mellanox.com; bor...@mellanox.com
> >> Subject: [PATCH net 2/4] tls: Fix write space handling
> >>
> >> TLS device cannot use the sw context. This patch returns the original
> >> tls device write space handler and moves the sw/device specific
> >> portions to the relevant files.
> >>
> >> Fixes: a42055e8d2c3 ("net/tls: Add support for async encryption of
> >> records for performance")
> >> Signed-off-by: Boris Pismenny <bor...@mellanox.com>
> >> Reviewed-by: Eran Ben Elisha <era...@mellanox.com>
> >> ---
> >> include/net/tls.h | 3 +++
> >> net/tls/tls_device.c | 16 ++++++++++++++++
> >> net/tls/tls_main.c | 17 +++++++++--------
> >> net/tls/tls_sw.c | 15 +++++++++++++++
> >> 4 files changed, 43 insertions(+), 8 deletions(-)
> >>
> >> diff --git a/include/net/tls.h b/include/net/tls.h index
> >> a528a082da73..9d7c53737b13 100644
> >> --- a/include/net/tls.h
> >> +++ b/include/net/tls.h
> >> @@ -519,6 +519,9 @@ static inline bool tls_sw_has_ctx_tx(const struct
> >> sock
> >> *sk)
> >> return !!tls_sw_ctx_tx(ctx);
> >> }
> >>
> >> +int tls_sw_write_space(struct sock *sk, struct tls_context *ctx);
> >> +int tls_device_write_space(struct sock *sk, struct tls_context
> >> +*ctx);
> >> +
> >> static inline struct tls_offload_context_rx *
> >> tls_offload_ctx_rx(const struct tls_context *tls_ctx)
> >> {
> >> diff --git a/net/tls/tls_device.c b/net/tls/tls_device.c index
> >> 3e5e8e021a87..e8988b3f3236 100644
> >> --- a/net/tls/tls_device.c
> >> +++ b/net/tls/tls_device.c
> >> @@ -546,6 +546,22 @@ static int tls_device_push_pending_record(struct
> >> sock *sk, int flags)
> >> return tls_push_data(sk, &msg_iter, 0, flags,
> >> TLS_RECORD_TYPE_DATA);
> >> }
> >>
> >> +int tls_device_write_space(struct sock *sk, struct tls_context *ctx)
> >> +{
> >> + int rc = 0;
> >> +
> >> + if (!sk->sk_write_pending && tls_is_partially_sent_record(ctx)) {
> >> + gfp_t sk_allocation = sk->sk_allocation;
> >> +
> >> + sk->sk_allocation = GFP_ATOMIC;
> >> + rc = tls_push_partial_record(sk, ctx,
> >> + MSG_DONTWAIT |
> >> MSG_NOSIGNAL);
> >> + sk->sk_allocation = sk_allocation;
> >> + }
> >> +
> >> + return rc;
> >> +}
> >> +
> >> void handle_device_resync(struct sock *sk, u32 seq, u64 rcd_sn)
> >> {
> >> struct tls_context *tls_ctx = tls_get_ctx(sk); diff --git
> >> a/net/tls/tls_main.c b/net/tls/tls_main.c index
> >> 7e05af75536d..11c1980a75cb 100644
> >> --- a/net/tls/tls_main.c
> >> +++ b/net/tls/tls_main.c
> >> @@ -212,7 +212,7 @@ int tls_push_partial_record(struct sock *sk,
> >> struct tls_context *ctx,
> >> static void tls_write_space(struct sock *sk)
> >> {
> >> struct tls_context *ctx = tls_get_ctx(sk);
> >> - struct tls_sw_context_tx *tx_ctx = tls_sw_ctx_tx(ctx);
> >> + int rc;
> >>
> >> /* If in_tcp_sendpages call lower protocol write space handler
> >> * to ensure we wake up any waiting operations there. For example
> >> @@ -223,14 +223,15 @@ static void tls_write_space(struct sock *sk)
> >> return;
> >> }
> >>
> >> - /* Schedule the transmission if tx list is ready */
> >> - if (is_tx_ready(tx_ctx) && !sk->sk_write_pending) {
> >> - /* Schedule the transmission */
> >> - if (!test_and_set_bit(BIT_TX_SCHEDULED, &tx_ctx-
> >>> tx_bitmask))
> >> - schedule_delayed_work(&tx_ctx->tx_work.work, 0);
> >> - }
> >> +#ifdef CONFIG_TLS_DEVICE
> >> + if (ctx->tx_conf == TLS_HW)
> >> + rc = tls_device_write_space(sk, ctx);
> >> + else
> >> +#endif
> >> + rc = tls_sw_write_space(sk, ctx);
> >>
> >> - ctx->sk_write_space(sk);
> >> + if (!rc)
> >
> > Why do we need to check 'rc'?
> >
> > If it is required, then ' ctx->sk_write_space(sk)' can move to
> > tls_device_write_space() since tls_sw_write_space() always returns '0'.
> >
>
> It is not necessary in the software code path due to the delayed work that is
> there. But, we need in the device flow. I'll move it there.
>
Removal of ctx->sk_write_space(sk) has broken software code flow.
The ktls send stops and user space application waits infinitely.
When tls_write_space() gets invoked tcp has been able to transmit some data.
Shouldn't we unconditionally call ctx->sk_write_space() in order to inform
user space application about availability of buffer space?
Please advise. I would submit the patch.
>
> >> + ctx->sk_write_space(sk);
> >> }
> >>
> >> static void tls_ctx_free(struct tls_context *ctx)
> >> diff --git a/net/tls/tls_sw.c b/net/tls/tls_sw.c
> >> index 1cc830582fa8..4afa67b00aaf 100644
> >> --- a/net/tls/tls_sw.c
> >> +++ b/net/tls/tls_sw.c
> >> @@ -2126,6 +2126,21 @@ static void tx_work_handler(struct
> work_struct
> >> *work)
> >> release_sock(sk);
> >> }
> >>
> >> +int tls_sw_write_space(struct sock *sk, struct tls_context *ctx)
> >> +{
> >> + struct tls_sw_context_tx *tx_ctx = tls_sw_ctx_tx(ctx);
> >> +
> >> + /* Schedule the transmission if tx list is ready */
> >> + if (is_tx_ready(tx_ctx) && !sk->sk_write_pending) {
> >> + /* Schedule the transmission */
> >> + if (!test_and_set_bit(BIT_TX_SCHEDULED,
> >> + &tx_ctx->tx_bitmask))
> >> + schedule_delayed_work(&tx_ctx->tx_work.work, 0);
> >> + }
> >> +
> >> + return 0;
> >> +}
> >> +
> >> int tls_set_sw_offload(struct sock *sk, struct tls_context *ctx, int tx)
> >> {
> >> struct tls_context *tls_ctx = tls_get_ctx(sk);
> >> --
> >> 2.12.2
> >
