4.16-stable review patch. If anyone has any objections, please let me know.
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From: Chris Leech cleech@redhat.com
[ Upstream commit af17092810a887178195276255b7b31f8fbe7dbe ]
Instead of always multicasting responses, send a unicast netlink message directed at the correct pid. This will be needed if we ever want to support multiple userspace processes interacting with the kernel over iSCSI netlink simultaneously. Limitations can currently be seen if you attempt to run multiple iscsistart commands in parallel.
We've fixed up the userspace issues in iscsistart that prevented multiple instances from running, so now attempts to speed up booting by bringing up multiple iscsi sessions at once in the initramfs are just running into misrouted responses that this fixes.
Signed-off-by: Chris Leech cleech@redhat.com Reviewed-by: Lee Duncan lduncan@suse.com Signed-off-by: Martin K. Petersen martin.petersen@oracle.com Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/scsi/scsi_transport_iscsi.c | 29 ++++++++++++++++++----------- 1 file changed, 18 insertions(+), 11 deletions(-)
--- a/drivers/scsi/scsi_transport_iscsi.c +++ b/drivers/scsi/scsi_transport_iscsi.c @@ -2322,6 +2322,12 @@ iscsi_multicast_skb(struct sk_buff *skb, return nlmsg_multicast(nls, skb, 0, group, gfp); }
+static int +iscsi_unicast_skb(struct sk_buff *skb, u32 portid) +{ + return nlmsg_unicast(nls, skb, portid); +} + int iscsi_recv_pdu(struct iscsi_cls_conn *conn, struct iscsi_hdr *hdr, char *data, uint32_t data_size) { @@ -2524,14 +2530,11 @@ void iscsi_ping_comp_event(uint32_t host EXPORT_SYMBOL_GPL(iscsi_ping_comp_event);
static int -iscsi_if_send_reply(uint32_t group, int seq, int type, int done, int multi, - void *payload, int size) +iscsi_if_send_reply(u32 portid, int type, void *payload, int size) { struct sk_buff *skb; struct nlmsghdr *nlh; int len = nlmsg_total_size(size); - int flags = multi ? NLM_F_MULTI : 0; - int t = done ? NLMSG_DONE : type;
skb = alloc_skb(len, GFP_ATOMIC); if (!skb) { @@ -2539,10 +2542,9 @@ iscsi_if_send_reply(uint32_t group, int return -ENOMEM; }
- nlh = __nlmsg_put(skb, 0, 0, t, (len - sizeof(*nlh)), 0); - nlh->nlmsg_flags = flags; + nlh = __nlmsg_put(skb, 0, 0, type, (len - sizeof(*nlh)), 0); memcpy(nlmsg_data(nlh), payload, size); - return iscsi_multicast_skb(skb, group, GFP_ATOMIC); + return iscsi_unicast_skb(skb, portid); }
static int @@ -3470,6 +3472,7 @@ static int iscsi_if_recv_msg(struct sk_buff *skb, struct nlmsghdr *nlh, uint32_t *group) { int err = 0; + u32 portid; struct iscsi_uevent *ev = nlmsg_data(nlh); struct iscsi_transport *transport = NULL; struct iscsi_internal *priv; @@ -3490,10 +3493,12 @@ iscsi_if_recv_msg(struct sk_buff *skb, s if (!try_module_get(transport->owner)) return -EINVAL;
+ portid = NETLINK_CB(skb).portid; + switch (nlh->nlmsg_type) { case ISCSI_UEVENT_CREATE_SESSION: err = iscsi_if_create_session(priv, ep, ev, - NETLINK_CB(skb).portid, + portid, ev->u.c_session.initial_cmdsn, ev->u.c_session.cmds_max, ev->u.c_session.queue_depth); @@ -3506,7 +3511,7 @@ iscsi_if_recv_msg(struct sk_buff *skb, s }
err = iscsi_if_create_session(priv, ep, ev, - NETLINK_CB(skb).portid, + portid, ev->u.c_bound_session.initial_cmdsn, ev->u.c_bound_session.cmds_max, ev->u.c_bound_session.queue_depth); @@ -3664,6 +3669,8 @@ iscsi_if_recv_msg(struct sk_buff *skb, s static void iscsi_if_rx(struct sk_buff *skb) { + u32 portid = NETLINK_CB(skb).portid; + mutex_lock(&rx_queue_mutex); while (skb->len >= NLMSG_HDRLEN) { int err; @@ -3699,8 +3706,8 @@ iscsi_if_rx(struct sk_buff *skb) break; if (ev->type == ISCSI_UEVENT_GET_CHAP && !err) break; - err = iscsi_if_send_reply(group, nlh->nlmsg_seq, - nlh->nlmsg_type, 0, 0, ev, sizeof(*ev)); + err = iscsi_if_send_reply(portid, nlh->nlmsg_type, + ev, sizeof(*ev)); } while (err < 0 && err != -ECONNREFUSED && err != -ESRCH); skb_pull(skb, rlen); }