Re: [Qemu-devel] [PULLv4 27/32] slirp: improve send_packet() callback
Philippe Mathieu-Daudé, le jeu. 07 févr. 2019 19:31:49 +0100, a ecrit:
> > +if (ret < 0) {
> > +g_critical("Failed to send packet, ret: %ld", (long) ret);
>
> From the v3 discussion [*] I thought send_packet() would return a
> gssize, then we'd use G_GSSIZE_FORMAT here (and similarly use gssize
> instead ssize_t in this series).
> Anyway your fix is simpler.
That was the idea of my fix, yes :)
Samuel
Re: [Qemu-devel] [PULLv4 27/32] slirp: improve send_packet() callback
Hi Samuel,
On 2/7/19 3:03 PM, Samuel Thibault wrote:
> From: Marc-André Lureau
>
> Use a more descriptive name for the callback.
>
> Reuse the SlirpWriteCb type. Wrap it to check that all data has been written.
>
> Return a ssize_t for potential error handling and data-loss reporting.
>
> Signed-off-by: Marc-André Lureau
> Signed-off-by: Samuel Thibault
> ---
> include/net/net.h | 2 +-
> net/net.c | 4 ++--
> net/slirp.c | 9 +
> slirp/libslirp.h | 11 +++
> slirp/ncsi.c | 2 +-
> slirp/slirp.c | 18 +++---
> slirp/slirp.h | 2 ++
> 7 files changed, 33 insertions(+), 15 deletions(-)
>
> diff --git a/include/net/net.h b/include/net/net.h
> index 643295d163..075cc01267 100644
> --- a/include/net/net.h
> +++ b/include/net/net.h
> @@ -146,7 +146,7 @@ ssize_t qemu_sendv_packet(NetClientState *nc, const
> struct iovec *iov,
>int iovcnt);
> ssize_t qemu_sendv_packet_async(NetClientState *nc, const struct iovec *iov,
> int iovcnt, NetPacketSent *sent_cb);
> -void qemu_send_packet(NetClientState *nc, const uint8_t *buf, int size);
> +ssize_t qemu_send_packet(NetClientState *nc, const uint8_t *buf, int size);
> ssize_t qemu_send_packet_raw(NetClientState *nc, const uint8_t *buf, int
> size);
> ssize_t qemu_send_packet_async(NetClientState *nc, const uint8_t *buf,
> int size, NetPacketSent *sent_cb);
> diff --git a/net/net.c b/net/net.c
> index 3acbdccd61..5dcff7fe2a 100644
> --- a/net/net.c
> +++ b/net/net.c
> @@ -668,9 +668,9 @@ ssize_t qemu_send_packet_async(NetClientState *sender,
> buf, size, sent_cb);
> }
>
> -void qemu_send_packet(NetClientState *nc, const uint8_t *buf, int size)
> +ssize_t qemu_send_packet(NetClientState *nc, const uint8_t *buf, int size)
> {
> -qemu_send_packet_async(nc, buf, size, NULL);
> +return qemu_send_packet_async(nc, buf, size, NULL);
> }
>
> ssize_t qemu_send_packet_raw(NetClientState *nc, const uint8_t *buf, int
> size)
> diff --git a/net/slirp.c b/net/slirp.c
> index 7b4f9f5c5e..664ff1c002 100644
> --- a/net/slirp.c
> +++ b/net/slirp.c
> @@ -108,11 +108,12 @@ static void slirp_smb_cleanup(SlirpState *s);
> static inline void slirp_smb_cleanup(SlirpState *s) { }
> #endif
>
> -static void net_slirp_output(void *opaque, const uint8_t *pkt, int pkt_len)
> +static ssize_t net_slirp_send_packet(const void *pkt, size_t pkt_len,
> + void *opaque)
> {
> SlirpState *s = opaque;
>
> -qemu_send_packet(&s->nc, pkt, pkt_len);
> +return qemu_send_packet(&s->nc, pkt, pkt_len);
> }
>
> static ssize_t net_slirp_receive(NetClientState *nc, const uint8_t *buf,
> size_t size)
> @@ -197,7 +198,7 @@ static void net_slirp_unregister_poll_fd(int fd)
> }
>
> static const SlirpCb slirp_cb = {
> -.output = net_slirp_output,
> +.send_packet = net_slirp_send_packet,
> .guest_error = net_slirp_guest_error,
> .clock_get_ns = net_slirp_clock_get_ns,
> .timer_new = net_slirp_timer_new,
> @@ -780,7 +781,7 @@ static void guestfwd_read(void *opaque, const uint8_t
> *buf, int size)
> slirp_socket_recv(fwd->slirp, fwd->server, fwd->port, buf, size);
> }
>
> -static int guestfwd_write(const void *buf, size_t len, void *chr)
> +static ssize_t guestfwd_write(const void *buf, size_t len, void *chr)
> {
> return qemu_chr_fe_write_all(chr, buf, len);
> }
> diff --git a/slirp/libslirp.h b/slirp/libslirp.h
> index 02cbec9f8b..8e5d4ed11b 100644
> --- a/slirp/libslirp.h
> +++ b/slirp/libslirp.h
> @@ -15,7 +15,7 @@
>
> typedef struct Slirp Slirp;
>
> -typedef int (*SlirpWriteCb)(const void *buf, size_t len, void *opaque);
> +typedef ssize_t (*SlirpWriteCb)(const void *buf, size_t len, void *opaque);
> typedef void (*SlirpTimerCb)(void *opaque);
>
> /*
> @@ -23,10 +23,13 @@ typedef void (*SlirpTimerCb)(void *opaque);
> */
> typedef struct SlirpCb {
> /*
> - * Send an ethernet frame to the guest network. The opaque parameter
> - * is the one given to slirp_init().
> + * Send an ethernet frame to the guest network. The opaque
> + * parameter is the one given to slirp_init(). The function
> + * doesn't need to send all the data and may return + * buffering is done on libslirp side, so the data will be dropped
> + * in this case). <0 reports an IO error.
> */
> -void (*output)(void *opaque, const uint8_t *pkt, int pkt_len);
> +SlirpWriteCb send_packet;
> /* Print a message for an error due to guest misbehavior. */
> void (*guest_error)(const char *msg);
> /* Return the virtual clock value in nanoseconds */
> diff --git a/slirp/ncsi.c b/slirp/ncsi.c
> index 327f17543c..359f52c284 100644
> --- a/slirp/ncsi.c
> +++ b/slirp/ncsi.c
> @@ -162,5 +162,5 @@ void ncsi_input(Slirp *slirp, const uint8_t *pkt, int
> pkt_len)
> *pchecksu
[Qemu-devel] [PULLv4 27/32] slirp: improve send_packet() callback
From: Marc-André Lureau
Use a more descriptive name for the callback.
Reuse the SlirpWriteCb type. Wrap it to check that all data has been written.
Return a ssize_t for potential error handling and data-loss reporting.
Signed-off-by: Marc-André Lureau
Signed-off-by: Samuel Thibault
---
include/net/net.h | 2 +-
net/net.c | 4 ++--
net/slirp.c | 9 +
slirp/libslirp.h | 11 +++
slirp/ncsi.c | 2 +-
slirp/slirp.c | 18 +++---
slirp/slirp.h | 2 ++
7 files changed, 33 insertions(+), 15 deletions(-)
diff --git a/include/net/net.h b/include/net/net.h
index 643295d163..075cc01267 100644
--- a/include/net/net.h
+++ b/include/net/net.h
@@ -146,7 +146,7 @@ ssize_t qemu_sendv_packet(NetClientState *nc, const struct
iovec *iov,
int iovcnt);
ssize_t qemu_sendv_packet_async(NetClientState *nc, const struct iovec *iov,
int iovcnt, NetPacketSent *sent_cb);
-void qemu_send_packet(NetClientState *nc, const uint8_t *buf, int size);
+ssize_t qemu_send_packet(NetClientState *nc, const uint8_t *buf, int size);
ssize_t qemu_send_packet_raw(NetClientState *nc, const uint8_t *buf, int size);
ssize_t qemu_send_packet_async(NetClientState *nc, const uint8_t *buf,
int size, NetPacketSent *sent_cb);
diff --git a/net/net.c b/net/net.c
index 3acbdccd61..5dcff7fe2a 100644
--- a/net/net.c
+++ b/net/net.c
@@ -668,9 +668,9 @@ ssize_t qemu_send_packet_async(NetClientState *sender,
buf, size, sent_cb);
}
-void qemu_send_packet(NetClientState *nc, const uint8_t *buf, int size)
+ssize_t qemu_send_packet(NetClientState *nc, const uint8_t *buf, int size)
{
-qemu_send_packet_async(nc, buf, size, NULL);
+return qemu_send_packet_async(nc, buf, size, NULL);
}
ssize_t qemu_send_packet_raw(NetClientState *nc, const uint8_t *buf, int size)
diff --git a/net/slirp.c b/net/slirp.c
index 7b4f9f5c5e..664ff1c002 100644
--- a/net/slirp.c
+++ b/net/slirp.c
@@ -108,11 +108,12 @@ static void slirp_smb_cleanup(SlirpState *s);
static inline void slirp_smb_cleanup(SlirpState *s) { }
#endif
-static void net_slirp_output(void *opaque, const uint8_t *pkt, int pkt_len)
+static ssize_t net_slirp_send_packet(const void *pkt, size_t pkt_len,
+ void *opaque)
{
SlirpState *s = opaque;
-qemu_send_packet(&s->nc, pkt, pkt_len);
+return qemu_send_packet(&s->nc, pkt, pkt_len);
}
static ssize_t net_slirp_receive(NetClientState *nc, const uint8_t *buf,
size_t size)
@@ -197,7 +198,7 @@ static void net_slirp_unregister_poll_fd(int fd)
}
static const SlirpCb slirp_cb = {
-.output = net_slirp_output,
+.send_packet = net_slirp_send_packet,
.guest_error = net_slirp_guest_error,
.clock_get_ns = net_slirp_clock_get_ns,
.timer_new = net_slirp_timer_new,
@@ -780,7 +781,7 @@ static void guestfwd_read(void *opaque, const uint8_t *buf,
int size)
slirp_socket_recv(fwd->slirp, fwd->server, fwd->port, buf, size);
}
-static int guestfwd_write(const void *buf, size_t len, void *chr)
+static ssize_t guestfwd_write(const void *buf, size_t len, void *chr)
{
return qemu_chr_fe_write_all(chr, buf, len);
}
diff --git a/slirp/libslirp.h b/slirp/libslirp.h
index 02cbec9f8b..8e5d4ed11b 100644
--- a/slirp/libslirp.h
+++ b/slirp/libslirp.h
@@ -15,7 +15,7 @@
typedef struct Slirp Slirp;
-typedef int (*SlirpWriteCb)(const void *buf, size_t len, void *opaque);
+typedef ssize_t (*SlirpWriteCb)(const void *buf, size_t len, void *opaque);
typedef void (*SlirpTimerCb)(void *opaque);
/*
@@ -23,10 +23,13 @@ typedef void (*SlirpTimerCb)(void *opaque);
*/
typedef struct SlirpCb {
/*
- * Send an ethernet frame to the guest network. The opaque parameter
- * is the one given to slirp_init().
+ * Send an ethernet frame to the guest network. The opaque
+ * parameter is the one given to slirp_init(). The function
+ * doesn't need to send all the data and may return cb->output(slirp->opaque, ncsi_reply, ETH_HLEN + ncsi_rsp_len);
+slirp_send_packet_all(slirp, ncsi_reply, ETH_HLEN + ncsi_rsp_len);
}
diff --git a/slirp/slirp.c b/slirp/slirp.c
index 3304c83001..2bc53e3e12 100644
--- a/slirp/slirp.c
+++ b/slirp/slirp.c
@@ -800,7 +800,7 @@ static void arp_input(Slirp *slirp, const uint8_t *pkt, int
pkt_len)
rah->ar_sip = ah->ar_tip;
memcpy(rah->ar_tha, ah->ar_sha, ETH_ALEN);
rah->ar_tip = ah->ar_sip;
-slirp->cb->output(slirp->opaque, arp_reply, sizeof(arp_reply));
+slirp_send_packet_all(slirp, arp_reply, sizeof(arp_reply));
}
break;
case ARPOP_REPLY:
@@ -900,7 +900,7 @@ static int if_encap4(Slirp *slirp, struct mbuf *ifm, struct
ethhdr *eh,
/* target IP */
rah->ar_tip = iph->ip_dst.s_addr;
slirp->client_ipaddr = iph->ip_dst;
-slirp
