net/smc: implement DMB-related operations of loopback-ism

This implements DMB (un)registration and data move operations of
loopback-ism device.

Signed-off-by: Wen Gu <guwen@linux.alibaba.com>
Reviewed-by: Wenjia Zhang <wenjia@linux.ibm.com>
Reviewed-and-tested-by: Jan Karcher <jaka@linux.ibm.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
This commit is contained in:
Wen Gu 2024-04-28 14:07:31 +08:00 committed by Paolo Abeni
parent 45783ee85b
commit f7a22071db
2 changed files with 139 additions and 3 deletions

View File

@ -15,10 +15,12 @@
#include <linux/types.h>
#include <net/smc.h>
#include "smc_cdc.h"
#include "smc_ism.h"
#include "smc_loopback.h"
#define SMC_LO_V2_CAPABLE 0x1 /* loopback-ism acts as ISMv2 */
#define SMC_DMA_ADDR_INVALID (~(dma_addr_t)0)
static const char smc_lo_dev_name[] = "loopback-ism";
static struct smc_lo_dev *lo_dev;
@ -48,6 +50,125 @@ static int smc_lo_query_rgid(struct smcd_dev *smcd, struct smcd_gid *rgid,
return 0;
}
static int smc_lo_register_dmb(struct smcd_dev *smcd, struct smcd_dmb *dmb,
void *client_priv)
{
struct smc_lo_dmb_node *dmb_node, *tmp_node;
struct smc_lo_dev *ldev = smcd->priv;
int sba_idx, rc;
/* check space for new dmb */
for_each_clear_bit(sba_idx, ldev->sba_idx_mask, SMC_LO_MAX_DMBS) {
if (!test_and_set_bit(sba_idx, ldev->sba_idx_mask))
break;
}
if (sba_idx == SMC_LO_MAX_DMBS)
return -ENOSPC;
dmb_node = kzalloc(sizeof(*dmb_node), GFP_KERNEL);
if (!dmb_node) {
rc = -ENOMEM;
goto err_bit;
}
dmb_node->sba_idx = sba_idx;
dmb_node->len = dmb->dmb_len;
dmb_node->cpu_addr = kzalloc(dmb_node->len, GFP_KERNEL |
__GFP_NOWARN | __GFP_NORETRY |
__GFP_NOMEMALLOC);
if (!dmb_node->cpu_addr) {
rc = -ENOMEM;
goto err_node;
}
dmb_node->dma_addr = SMC_DMA_ADDR_INVALID;
again:
/* add new dmb into hash table */
get_random_bytes(&dmb_node->token, sizeof(dmb_node->token));
write_lock_bh(&ldev->dmb_ht_lock);
hash_for_each_possible(ldev->dmb_ht, tmp_node, list, dmb_node->token) {
if (tmp_node->token == dmb_node->token) {
write_unlock_bh(&ldev->dmb_ht_lock);
goto again;
}
}
hash_add(ldev->dmb_ht, &dmb_node->list, dmb_node->token);
write_unlock_bh(&ldev->dmb_ht_lock);
dmb->sba_idx = dmb_node->sba_idx;
dmb->dmb_tok = dmb_node->token;
dmb->cpu_addr = dmb_node->cpu_addr;
dmb->dma_addr = dmb_node->dma_addr;
dmb->dmb_len = dmb_node->len;
return 0;
err_node:
kfree(dmb_node);
err_bit:
clear_bit(sba_idx, ldev->sba_idx_mask);
return rc;
}
static int smc_lo_unregister_dmb(struct smcd_dev *smcd, struct smcd_dmb *dmb)
{
struct smc_lo_dmb_node *dmb_node = NULL, *tmp_node;
struct smc_lo_dev *ldev = smcd->priv;
/* remove dmb from hash table */
write_lock_bh(&ldev->dmb_ht_lock);
hash_for_each_possible(ldev->dmb_ht, tmp_node, list, dmb->dmb_tok) {
if (tmp_node->token == dmb->dmb_tok) {
dmb_node = tmp_node;
break;
}
}
if (!dmb_node) {
write_unlock_bh(&ldev->dmb_ht_lock);
return -EINVAL;
}
hash_del(&dmb_node->list);
write_unlock_bh(&ldev->dmb_ht_lock);
clear_bit(dmb_node->sba_idx, ldev->sba_idx_mask);
kfree(dmb_node->cpu_addr);
kfree(dmb_node);
return 0;
}
static int smc_lo_move_data(struct smcd_dev *smcd, u64 dmb_tok,
unsigned int idx, bool sf, unsigned int offset,
void *data, unsigned int size)
{
struct smc_lo_dmb_node *rmb_node = NULL, *tmp_node;
struct smc_lo_dev *ldev = smcd->priv;
struct smc_connection *conn;
read_lock_bh(&ldev->dmb_ht_lock);
hash_for_each_possible(ldev->dmb_ht, tmp_node, list, dmb_tok) {
if (tmp_node->token == dmb_tok) {
rmb_node = tmp_node;
break;
}
}
if (!rmb_node) {
read_unlock_bh(&ldev->dmb_ht_lock);
return -EINVAL;
}
memcpy((char *)rmb_node->cpu_addr + offset, data, size);
read_unlock_bh(&ldev->dmb_ht_lock);
if (sf) {
conn = smcd->conn[rmb_node->sba_idx];
if (conn && !conn->killed)
tasklet_schedule(&conn->rx_tsklet);
else
return -EPIPE;
}
return 0;
}
static int smc_lo_supports_v2(void)
{
return SMC_LO_V2_CAPABLE;
@ -74,14 +195,14 @@ static struct device *smc_lo_get_dev(struct smcd_dev *smcd)
static const struct smcd_ops lo_ops = {
.query_remote_gid = smc_lo_query_rgid,
.register_dmb = NULL,
.unregister_dmb = NULL,
.register_dmb = smc_lo_register_dmb,
.unregister_dmb = smc_lo_unregister_dmb,
.add_vlan_id = NULL,
.del_vlan_id = NULL,
.set_vlan_required = NULL,
.reset_vlan_required = NULL,
.signal_event = NULL,
.move_data = NULL,
.move_data = smc_lo_move_data,
.supports_v2 = smc_lo_supports_v2,
.get_local_gid = smc_lo_get_local_gid,
.get_chid = smc_lo_get_chid,
@ -146,6 +267,8 @@ static void smcd_lo_unregister_dev(struct smc_lo_dev *ldev)
static int smc_lo_dev_init(struct smc_lo_dev *ldev)
{
smc_lo_generate_ids(ldev);
rwlock_init(&ldev->dmb_ht_lock);
hash_init(ldev->dmb_ht);
return smcd_lo_register_dev(ldev);
}

View File

@ -20,13 +20,26 @@
#if IS_ENABLED(CONFIG_SMC_LO)
#define SMC_LO_MAX_DMBS 5000
#define SMC_LO_DMBS_HASH_BITS 12
#define SMC_LO_RESERVED_CHID 0xFFFF
struct smc_lo_dmb_node {
struct hlist_node list;
u64 token;
u32 len;
u32 sba_idx;
void *cpu_addr;
dma_addr_t dma_addr;
};
struct smc_lo_dev {
struct smcd_dev *smcd;
struct device dev;
u16 chid;
struct smcd_gid local_gid;
rwlock_t dmb_ht_lock;
DECLARE_BITMAP(sba_idx_mask, SMC_LO_MAX_DMBS);
DECLARE_HASHTABLE(dmb_ht, SMC_LO_DMBS_HASH_BITS);
};
int smc_loopback_init(void);