net/smc: add SMC-D support in data transfer

The data transfer and CDC message headers differ in SMC-R and SMC-D.
This patch adds support for the SMC-D data transfer to the existing SMC
code. It consists of the following:

* SMC-D CDC support
* SMC-D tx support
* SMC-D rx support

The CDC header is stored at the beginning of the receive buffer. Thus, a
rx_offset variable is added for the CDC header offset within the buffer
(0 for SMC-R).

Signed-off-by: Hans Wippel <hwippel@linux.ibm.com>
Signed-off-by: Ursula Braun <ubraun@linux.ibm.com>
Suggested-by: Thomas Richter <tmricht@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Hans Wippel 2018-06-28 19:05:10 +02:00 committed by David S. Miller
parent c758dfddc1
commit be244f28d2
8 changed files with 308 additions and 56 deletions

View File

@ -183,6 +183,11 @@ struct smc_connection {
spinlock_t acurs_lock; /* protect cursors */
#endif
struct work_struct close_work; /* peer sent some closing */
struct tasklet_struct rx_tsklet; /* Receiver tasklet for SMC-D */
u8 rx_off; /* receive offset:
* 0 for SMC-R, 32 for SMC-D
*/
u64 peer_token; /* SMC-D token of peer */
};
struct smc_sock { /* smc sock container */

View File

@ -117,7 +117,7 @@ int smc_cdc_msg_send(struct smc_connection *conn,
return rc;
}
int smc_cdc_get_slot_and_msg_send(struct smc_connection *conn)
static int smcr_cdc_get_slot_and_msg_send(struct smc_connection *conn)
{
struct smc_cdc_tx_pend *pend;
struct smc_wr_buf *wr_buf;
@ -130,6 +130,21 @@ int smc_cdc_get_slot_and_msg_send(struct smc_connection *conn)
return smc_cdc_msg_send(conn, wr_buf, pend);
}
int smc_cdc_get_slot_and_msg_send(struct smc_connection *conn)
{
int rc;
if (conn->lgr->is_smcd) {
spin_lock_bh(&conn->send_lock);
rc = smcd_cdc_msg_send(conn);
spin_unlock_bh(&conn->send_lock);
} else {
rc = smcr_cdc_get_slot_and_msg_send(conn);
}
return rc;
}
static bool smc_cdc_tx_filter(struct smc_wr_tx_pend_priv *tx_pend,
unsigned long data)
{
@ -157,6 +172,45 @@ void smc_cdc_tx_dismiss_slots(struct smc_connection *conn)
(unsigned long)conn);
}
/* Send a SMC-D CDC header.
* This increments the free space available in our send buffer.
* Also update the confirmed receive buffer with what was sent to the peer.
*/
int smcd_cdc_msg_send(struct smc_connection *conn)
{
struct smc_sock *smc = container_of(conn, struct smc_sock, conn);
struct smcd_cdc_msg cdc;
int rc, diff;
memset(&cdc, 0, sizeof(cdc));
cdc.common.type = SMC_CDC_MSG_TYPE;
cdc.prod_wrap = conn->local_tx_ctrl.prod.wrap;
cdc.prod_count = conn->local_tx_ctrl.prod.count;
cdc.cons_wrap = conn->local_tx_ctrl.cons.wrap;
cdc.cons_count = conn->local_tx_ctrl.cons.count;
cdc.prod_flags = conn->local_tx_ctrl.prod_flags;
cdc.conn_state_flags = conn->local_tx_ctrl.conn_state_flags;
rc = smcd_tx_ism_write(conn, &cdc, sizeof(cdc), 0, 1);
if (rc)
return rc;
smc_curs_write(&conn->rx_curs_confirmed,
smc_curs_read(&conn->local_tx_ctrl.cons, conn), conn);
/* Calculate transmitted data and increment free send buffer space */
diff = smc_curs_diff(conn->sndbuf_desc->len, &conn->tx_curs_fin,
&conn->tx_curs_sent);
/* increased by confirmed number of bytes */
smp_mb__before_atomic();
atomic_add(diff, &conn->sndbuf_space);
/* guarantee 0 <= sndbuf_space <= sndbuf_desc->len */
smp_mb__after_atomic();
smc_curs_write(&conn->tx_curs_fin,
smc_curs_read(&conn->tx_curs_sent, conn), conn);
smc_tx_sndbuf_nonfull(smc);
return rc;
}
/********************************* receive ***********************************/
static inline bool smc_cdc_before(u16 seq1, u16 seq2)
@ -178,7 +232,7 @@ static void smc_cdc_handle_urg_data_arrival(struct smc_sock *smc,
if (!sock_flag(&smc->sk, SOCK_URGINLINE))
/* we'll skip the urgent byte, so don't account for it */
(*diff_prod)--;
base = (char *)conn->rmb_desc->cpu_addr;
base = (char *)conn->rmb_desc->cpu_addr + conn->rx_off;
if (conn->urg_curs.count)
conn->urg_rx_byte = *(base + conn->urg_curs.count - 1);
else
@ -276,6 +330,34 @@ static void smc_cdc_msg_recv(struct smc_sock *smc, struct smc_cdc_msg *cdc)
sock_put(&smc->sk); /* no free sk in softirq-context */
}
/* Schedule a tasklet for this connection. Triggered from the ISM device IRQ
* handler to indicate update in the DMBE.
*
* Context:
* - tasklet context
*/
static void smcd_cdc_rx_tsklet(unsigned long data)
{
struct smc_connection *conn = (struct smc_connection *)data;
struct smcd_cdc_msg cdc;
struct smc_sock *smc;
if (!conn)
return;
memcpy(&cdc, conn->rmb_desc->cpu_addr, sizeof(cdc));
smc = container_of(conn, struct smc_sock, conn);
smc_cdc_msg_recv(smc, (struct smc_cdc_msg *)&cdc);
}
/* Initialize receive tasklet. Called from ISM device IRQ handler to start
* receiver side.
*/
void smcd_cdc_rx_init(struct smc_connection *conn)
{
tasklet_init(&conn->rx_tsklet, smcd_cdc_rx_tsklet, (unsigned long)conn);
}
/***************************** init, exit, misc ******************************/
static void smc_cdc_rx_handler(struct ib_wc *wc, void *buf)

View File

@ -50,6 +50,20 @@ struct smc_cdc_msg {
u8 reserved[18];
} __packed; /* format defined in RFC7609 */
/* CDC message for SMC-D */
struct smcd_cdc_msg {
struct smc_wr_rx_hdr common; /* Type = 0xFE */
u8 res1[7];
u16 prod_wrap;
u32 prod_count;
u8 res2[2];
u16 cons_wrap;
u32 cons_count;
struct smc_cdc_producer_flags prod_flags;
struct smc_cdc_conn_state_flags conn_state_flags;
u8 res3[8];
} __packed;
static inline bool smc_cdc_rxed_any_close(struct smc_connection *conn)
{
return conn->local_rx_ctrl.conn_state_flags.peer_conn_abort ||
@ -204,9 +218,9 @@ static inline void smc_cdc_cursor_to_host(union smc_host_cursor *local,
smc_curs_write(local, smc_curs_read(&temp, conn), conn);
}
static inline void smc_cdc_msg_to_host(struct smc_host_cdc_msg *local,
struct smc_cdc_msg *peer,
struct smc_connection *conn)
static inline void smcr_cdc_msg_to_host(struct smc_host_cdc_msg *local,
struct smc_cdc_msg *peer,
struct smc_connection *conn)
{
local->common.type = peer->common.type;
local->len = peer->len;
@ -218,6 +232,27 @@ static inline void smc_cdc_msg_to_host(struct smc_host_cdc_msg *local,
local->conn_state_flags = peer->conn_state_flags;
}
static inline void smcd_cdc_msg_to_host(struct smc_host_cdc_msg *local,
struct smcd_cdc_msg *peer)
{
local->prod.wrap = peer->prod_wrap;
local->prod.count = peer->prod_count;
local->cons.wrap = peer->cons_wrap;
local->cons.count = peer->cons_count;
local->prod_flags = peer->prod_flags;
local->conn_state_flags = peer->conn_state_flags;
}
static inline void smc_cdc_msg_to_host(struct smc_host_cdc_msg *local,
struct smc_cdc_msg *peer,
struct smc_connection *conn)
{
if (conn->lgr->is_smcd)
smcd_cdc_msg_to_host(local, (struct smcd_cdc_msg *)peer);
else
smcr_cdc_msg_to_host(local, peer, conn);
}
struct smc_cdc_tx_pend;
int smc_cdc_get_free_slot(struct smc_connection *conn,
@ -227,6 +262,8 @@ void smc_cdc_tx_dismiss_slots(struct smc_connection *conn);
int smc_cdc_msg_send(struct smc_connection *conn, struct smc_wr_buf *wr_buf,
struct smc_cdc_tx_pend *pend);
int smc_cdc_get_slot_and_msg_send(struct smc_connection *conn);
int smcd_cdc_msg_send(struct smc_connection *conn);
int smc_cdc_init(void) __init;
void smcd_cdc_rx_init(struct smc_connection *conn);
#endif /* SMC_CDC_H */

View File

@ -281,10 +281,12 @@ void smc_conn_free(struct smc_connection *conn)
{
if (!conn->lgr)
return;
if (conn->lgr->is_smcd)
if (conn->lgr->is_smcd) {
smc_ism_unset_conn(conn);
else
tasklet_kill(&conn->rx_tsklet);
} else {
smc_cdc_tx_dismiss_slots(conn);
}
smc_lgr_unregister_conn(conn);
smc_buf_unuse(conn);
}
@ -324,10 +326,13 @@ static void smcr_buf_free(struct smc_link_group *lgr, bool is_rmb,
static void smcd_buf_free(struct smc_link_group *lgr, bool is_dmb,
struct smc_buf_desc *buf_desc)
{
if (is_dmb)
if (is_dmb) {
/* restore original buf len */
buf_desc->len += sizeof(struct smcd_cdc_msg);
smc_ism_unregister_dmb(lgr->smcd, buf_desc);
else
} else {
kfree(buf_desc->cpu_addr);
}
kfree(buf_desc);
}
@ -632,6 +637,10 @@ create:
conn->local_tx_ctrl.common.type = SMC_CDC_MSG_TYPE;
conn->local_tx_ctrl.len = SMC_WR_TX_SIZE;
conn->urg_state = SMC_URG_READ;
if (is_smcd) {
conn->rx_off = sizeof(struct smcd_cdc_msg);
smcd_cdc_rx_init(conn); /* init tasklet for this conn */
}
#ifndef KERNEL_HAS_ATOMIC64
spin_lock_init(&conn->acurs_lock);
#endif
@ -776,8 +785,9 @@ static struct smc_buf_desc *smcd_new_buf_create(struct smc_link_group *lgr,
kfree(buf_desc);
return ERR_PTR(-EAGAIN);
}
memset(buf_desc->cpu_addr, 0, bufsize);
buf_desc->len = bufsize;
buf_desc->pages = virt_to_page(buf_desc->cpu_addr);
/* CDC header stored in buf. So, pretend it was smaller */
buf_desc->len = bufsize - sizeof(struct smcd_cdc_msg);
} else {
buf_desc->cpu_addr = kzalloc(bufsize, GFP_KERNEL |
__GFP_NOWARN | __GFP_NORETRY |
@ -854,7 +864,8 @@ static int __smc_buf_create(struct smc_sock *smc, bool is_smcd, bool is_rmb)
conn->rmbe_size_short = bufsize_short;
smc->sk.sk_rcvbuf = bufsize * 2;
atomic_set(&conn->bytes_to_rcv, 0);
conn->rmbe_update_limit = smc_rmb_wnd_update_limit(bufsize);
conn->rmbe_update_limit =
smc_rmb_wnd_update_limit(buf_desc->len);
if (is_smcd)
smc_ism_set_conn(conn); /* map RMB/smcd_dev to conn */
} else {

View File

@ -302,5 +302,13 @@ EXPORT_SYMBOL_GPL(smcd_handle_event);
*/
void smcd_handle_irq(struct smcd_dev *smcd, unsigned int dmbno)
{
struct smc_connection *conn = NULL;
unsigned long flags;
spin_lock_irqsave(&smcd->lock, flags);
conn = smcd->conn[dmbno];
if (conn)
tasklet_schedule(&conn->rx_tsklet);
spin_unlock_irqrestore(&smcd->lock, flags);
}
EXPORT_SYMBOL_GPL(smcd_handle_irq);

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@ -305,7 +305,7 @@ int smc_rx_recvmsg(struct smc_sock *smc, struct msghdr *msg,
target = sock_rcvlowat(sk, flags & MSG_WAITALL, len);
/* we currently use 1 RMBE per RMB, so RMBE == RMB base addr */
rcvbuf_base = conn->rmb_desc->cpu_addr;
rcvbuf_base = conn->rx_off + conn->rmb_desc->cpu_addr;
do { /* while (read_remaining) */
if (read_done >= target || (pipe && read_done))

View File

@ -24,6 +24,7 @@
#include "smc.h"
#include "smc_wr.h"
#include "smc_cdc.h"
#include "smc_ism.h"
#include "smc_tx.h"
#define SMC_TX_WORK_DELAY HZ
@ -250,6 +251,24 @@ out_err:
/***************************** sndbuf consumer *******************************/
/* sndbuf consumer: actual data transfer of one target chunk with ISM write */
int smcd_tx_ism_write(struct smc_connection *conn, void *data, size_t len,
u32 offset, int signal)
{
struct smc_ism_position pos;
int rc;
memset(&pos, 0, sizeof(pos));
pos.token = conn->peer_token;
pos.index = conn->peer_rmbe_idx;
pos.offset = conn->tx_off + offset;
pos.signal = signal;
rc = smc_ism_write(conn->lgr->smcd, &pos, data, len);
if (rc)
conn->local_tx_ctrl.conn_state_flags.peer_conn_abort = 1;
return rc;
}
/* sndbuf consumer: actual data transfer of one target chunk with RDMA write */
static int smc_tx_rdma_write(struct smc_connection *conn, int peer_rmbe_offset,
int num_sges, struct ib_sge sges[])
@ -297,21 +316,104 @@ static inline void smc_tx_advance_cursors(struct smc_connection *conn,
smc_curs_add(conn->sndbuf_desc->len, sent, len);
}
/* SMC-R helper for smc_tx_rdma_writes() */
static int smcr_tx_rdma_writes(struct smc_connection *conn, size_t len,
size_t src_off, size_t src_len,
size_t dst_off, size_t dst_len)
{
dma_addr_t dma_addr =
sg_dma_address(conn->sndbuf_desc->sgt[SMC_SINGLE_LINK].sgl);
struct smc_link *link = &conn->lgr->lnk[SMC_SINGLE_LINK];
int src_len_sum = src_len, dst_len_sum = dst_len;
struct ib_sge sges[SMC_IB_MAX_SEND_SGE];
int sent_count = src_off;
int srcchunk, dstchunk;
int num_sges;
int rc;
for (dstchunk = 0; dstchunk < 2; dstchunk++) {
num_sges = 0;
for (srcchunk = 0; srcchunk < 2; srcchunk++) {
sges[srcchunk].addr = dma_addr + src_off;
sges[srcchunk].length = src_len;
sges[srcchunk].lkey = link->roce_pd->local_dma_lkey;
num_sges++;
src_off += src_len;
if (src_off >= conn->sndbuf_desc->len)
src_off -= conn->sndbuf_desc->len;
/* modulo in send ring */
if (src_len_sum == dst_len)
break; /* either on 1st or 2nd iteration */
/* prepare next (== 2nd) iteration */
src_len = dst_len - src_len; /* remainder */
src_len_sum += src_len;
}
rc = smc_tx_rdma_write(conn, dst_off, num_sges, sges);
if (rc)
return rc;
if (dst_len_sum == len)
break; /* either on 1st or 2nd iteration */
/* prepare next (== 2nd) iteration */
dst_off = 0; /* modulo offset in RMBE ring buffer */
dst_len = len - dst_len; /* remainder */
dst_len_sum += dst_len;
src_len = min_t(int, dst_len, conn->sndbuf_desc->len -
sent_count);
src_len_sum = src_len;
}
return 0;
}
/* SMC-D helper for smc_tx_rdma_writes() */
static int smcd_tx_rdma_writes(struct smc_connection *conn, size_t len,
size_t src_off, size_t src_len,
size_t dst_off, size_t dst_len)
{
int src_len_sum = src_len, dst_len_sum = dst_len;
int srcchunk, dstchunk;
int rc;
for (dstchunk = 0; dstchunk < 2; dstchunk++) {
for (srcchunk = 0; srcchunk < 2; srcchunk++) {
void *data = conn->sndbuf_desc->cpu_addr + src_off;
rc = smcd_tx_ism_write(conn, data, src_len, dst_off +
sizeof(struct smcd_cdc_msg), 0);
if (rc)
return rc;
dst_off += src_len;
src_off += src_len;
if (src_off >= conn->sndbuf_desc->len)
src_off -= conn->sndbuf_desc->len;
/* modulo in send ring */
if (src_len_sum == dst_len)
break; /* either on 1st or 2nd iteration */
/* prepare next (== 2nd) iteration */
src_len = dst_len - src_len; /* remainder */
src_len_sum += src_len;
}
if (dst_len_sum == len)
break; /* either on 1st or 2nd iteration */
/* prepare next (== 2nd) iteration */
dst_off = 0; /* modulo offset in RMBE ring buffer */
dst_len = len - dst_len; /* remainder */
dst_len_sum += dst_len;
src_len = min_t(int, dst_len, conn->sndbuf_desc->len - src_off);
src_len_sum = src_len;
}
return 0;
}
/* sndbuf consumer: prepare all necessary (src&dst) chunks of data transmit;
* usable snd_wnd as max transmit
*/
static int smc_tx_rdma_writes(struct smc_connection *conn)
{
size_t src_off, src_len, dst_off, dst_len; /* current chunk values */
size_t len, dst_len_sum, src_len_sum, dstchunk, srcchunk;
size_t len, src_len, dst_off, dst_len; /* current chunk values */
union smc_host_cursor sent, prep, prod, cons;
struct ib_sge sges[SMC_IB_MAX_SEND_SGE];
struct smc_link_group *lgr = conn->lgr;
struct smc_cdc_producer_flags *pflags;
int to_send, rmbespace;
struct smc_link *link;
dma_addr_t dma_addr;
int num_sges;
int rc;
/* source: sndbuf */
@ -341,7 +443,6 @@ static int smc_tx_rdma_writes(struct smc_connection *conn)
len = min(to_send, rmbespace);
/* initialize variables for first iteration of subsequent nested loop */
link = &lgr->lnk[SMC_SINGLE_LINK];
dst_off = prod.count;
if (prod.wrap == cons.wrap) {
/* the filled destination area is unwrapped,
@ -358,8 +459,6 @@ static int smc_tx_rdma_writes(struct smc_connection *conn)
*/
dst_len = len;
}
dst_len_sum = dst_len;
src_off = sent.count;
/* dst_len determines the maximum src_len */
if (sent.count + dst_len <= conn->sndbuf_desc->len) {
/* unwrapped src case: single chunk of entire dst_len */
@ -368,38 +467,15 @@ static int smc_tx_rdma_writes(struct smc_connection *conn)
/* wrapped src case: 2 chunks of sum dst_len; start with 1st: */
src_len = conn->sndbuf_desc->len - sent.count;
}
src_len_sum = src_len;
dma_addr = sg_dma_address(conn->sndbuf_desc->sgt[SMC_SINGLE_LINK].sgl);
for (dstchunk = 0; dstchunk < 2; dstchunk++) {
num_sges = 0;
for (srcchunk = 0; srcchunk < 2; srcchunk++) {
sges[srcchunk].addr = dma_addr + src_off;
sges[srcchunk].length = src_len;
sges[srcchunk].lkey = link->roce_pd->local_dma_lkey;
num_sges++;
src_off += src_len;
if (src_off >= conn->sndbuf_desc->len)
src_off -= conn->sndbuf_desc->len;
/* modulo in send ring */
if (src_len_sum == dst_len)
break; /* either on 1st or 2nd iteration */
/* prepare next (== 2nd) iteration */
src_len = dst_len - src_len; /* remainder */
src_len_sum += src_len;
}
rc = smc_tx_rdma_write(conn, dst_off, num_sges, sges);
if (rc)
return rc;
if (dst_len_sum == len)
break; /* either on 1st or 2nd iteration */
/* prepare next (== 2nd) iteration */
dst_off = 0; /* modulo offset in RMBE ring buffer */
dst_len = len - dst_len; /* remainder */
dst_len_sum += dst_len;
src_len = min_t(int,
dst_len, conn->sndbuf_desc->len - sent.count);
src_len_sum = src_len;
}
if (conn->lgr->is_smcd)
rc = smcd_tx_rdma_writes(conn, len, sent.count, src_len,
dst_off, dst_len);
else
rc = smcr_tx_rdma_writes(conn, len, sent.count, src_len,
dst_off, dst_len);
if (rc)
return rc;
if (conn->urg_tx_pend && len == to_send)
pflags->urg_data_present = 1;
@ -420,7 +496,7 @@ static int smc_tx_rdma_writes(struct smc_connection *conn)
/* Wakeup sndbuf consumers from any context (IRQ or process)
* since there is more data to transmit; usable snd_wnd as max transmit
*/
int smc_tx_sndbuf_nonempty(struct smc_connection *conn)
static int smcr_tx_sndbuf_nonempty(struct smc_connection *conn)
{
struct smc_cdc_producer_flags *pflags;
struct smc_cdc_tx_pend *pend;
@ -467,6 +543,37 @@ out_unlock:
return rc;
}
static int smcd_tx_sndbuf_nonempty(struct smc_connection *conn)
{
struct smc_cdc_producer_flags *pflags = &conn->local_tx_ctrl.prod_flags;
int rc = 0;
spin_lock_bh(&conn->send_lock);
if (!pflags->urg_data_present)
rc = smc_tx_rdma_writes(conn);
if (!rc)
rc = smcd_cdc_msg_send(conn);
if (!rc && pflags->urg_data_present) {
pflags->urg_data_pending = 0;
pflags->urg_data_present = 0;
}
spin_unlock_bh(&conn->send_lock);
return rc;
}
int smc_tx_sndbuf_nonempty(struct smc_connection *conn)
{
int rc;
if (conn->lgr->is_smcd)
rc = smcd_tx_sndbuf_nonempty(conn);
else
rc = smcr_tx_sndbuf_nonempty(conn);
return rc;
}
/* Wakeup sndbuf consumers from process context
* since there is more data to transmit
*/

View File

@ -33,5 +33,7 @@ int smc_tx_sendmsg(struct smc_sock *smc, struct msghdr *msg, size_t len);
int smc_tx_sndbuf_nonempty(struct smc_connection *conn);
void smc_tx_sndbuf_nonfull(struct smc_sock *smc);
void smc_tx_consumer_update(struct smc_connection *conn, bool force);
int smcd_tx_ism_write(struct smc_connection *conn, void *data, size_t len,
u32 offset, int signal);
#endif /* SMC_TX_H */