From 8f6fd83c6c5ec66a4a70c728535ddcdfef4f3697 Mon Sep 17 00:00:00 2001 From: Bob Copeland Date: Wed, 2 Mar 2016 10:09:19 -0500 Subject: rhashtable: accept GFP flags in rhashtable_walk_init In certain cases, the 802.11 mesh pathtable code wants to iterate over all of the entries in the forwarding table from the receive path, which is inside an RCU read-side critical section. Enable walks inside atomic sections by allowing GFP_ATOMIC allocations for the walker state. Change all existing callsites to pass in GFP_KERNEL. Acked-by: Thomas Graf Signed-off-by: Bob Copeland [also adjust gfs2/glock.c and rhashtable tests] Signed-off-by: Johannes Berg --- net/sctp/proc.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'net/sctp/proc.c') diff --git a/net/sctp/proc.c b/net/sctp/proc.c index 5cfac8d5d3b3..6d45d53321e6 100644 --- a/net/sctp/proc.c +++ b/net/sctp/proc.c @@ -319,7 +319,8 @@ static int sctp_transport_walk_start(struct seq_file *seq) struct sctp_ht_iter *iter = seq->private; int err; - err = rhashtable_walk_init(&sctp_transport_hashtable, &iter->hti); + err = rhashtable_walk_init(&sctp_transport_hashtable, &iter->hti, + GFP_KERNEL); if (err) return err; -- cgit v1.2.3 From 626d16f50f39bb9c44f98fd256cae2b864900a01 Mon Sep 17 00:00:00 2001 From: Xin Long Date: Thu, 14 Apr 2016 15:35:31 +0800 Subject: sctp: export some apis or variables for sctp_diag and reuse some for proc For some main variables in sctp.ko, we couldn't export it to other modules, so we have to define some api to access them. It will include sctp transport and endpoint's traversal. There are some transport traversal functions for sctp_diag, we can also use it for sctp_proc. cause they have the similar situation to traversal transport. v2->v3: - rhashtable_walk_init need the parameter gfp, because of recent upstrem update Signed-off-by: Xin Long Signed-off-by: David S. Miller --- include/net/sctp/sctp.h | 13 +++++ net/sctp/proc.c | 81 +++++++------------------------ net/sctp/socket.c | 125 ++++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 156 insertions(+), 63 deletions(-) (limited to 'net/sctp/proc.c') diff --git a/include/net/sctp/sctp.h b/include/net/sctp/sctp.h index 268b10058ef5..3f1c0ff7d4b6 100644 --- a/include/net/sctp/sctp.h +++ b/include/net/sctp/sctp.h @@ -116,6 +116,19 @@ extern struct percpu_counter sctp_sockets_allocated; int sctp_asconf_mgmt(struct sctp_sock *, struct sctp_sockaddr_entry *); struct sk_buff *sctp_skb_recv_datagram(struct sock *, int, int, int *); +int sctp_transport_walk_start(struct rhashtable_iter *iter); +void sctp_transport_walk_stop(struct rhashtable_iter *iter); +struct sctp_transport *sctp_transport_get_next(struct net *net, + struct rhashtable_iter *iter); +struct sctp_transport *sctp_transport_get_idx(struct net *net, + struct rhashtable_iter *iter, int pos); +int sctp_transport_lookup_process(int (*cb)(struct sctp_transport *, void *), + struct net *net, + const union sctp_addr *laddr, + const union sctp_addr *paddr, void *p); +int sctp_for_each_transport(int (*cb)(struct sctp_transport *, void *), + struct net *net, int pos, void *p); +int sctp_for_each_endpoint(int (*cb)(struct sctp_endpoint *, void *), void *p); int sctp_get_sctp_info(struct sock *sk, struct sctp_association *asoc, struct sctp_info *info); diff --git a/net/sctp/proc.c b/net/sctp/proc.c index 6d45d53321e6..dd8492f0037d 100644 --- a/net/sctp/proc.c +++ b/net/sctp/proc.c @@ -282,81 +282,31 @@ struct sctp_ht_iter { struct rhashtable_iter hti; }; -static struct sctp_transport *sctp_transport_get_next(struct seq_file *seq) -{ - struct sctp_ht_iter *iter = seq->private; - struct sctp_transport *t; - - t = rhashtable_walk_next(&iter->hti); - for (; t; t = rhashtable_walk_next(&iter->hti)) { - if (IS_ERR(t)) { - if (PTR_ERR(t) == -EAGAIN) - continue; - break; - } - - if (net_eq(sock_net(t->asoc->base.sk), seq_file_net(seq)) && - t->asoc->peer.primary_path == t) - break; - } - - return t; -} - -static struct sctp_transport *sctp_transport_get_idx(struct seq_file *seq, - loff_t pos) -{ - void *obj = SEQ_START_TOKEN; - - while (pos && (obj = sctp_transport_get_next(seq)) && !IS_ERR(obj)) - pos--; - - return obj; -} - -static int sctp_transport_walk_start(struct seq_file *seq) -{ - struct sctp_ht_iter *iter = seq->private; - int err; - - err = rhashtable_walk_init(&sctp_transport_hashtable, &iter->hti, - GFP_KERNEL); - if (err) - return err; - - err = rhashtable_walk_start(&iter->hti); - - return err == -EAGAIN ? 0 : err; -} - -static void sctp_transport_walk_stop(struct seq_file *seq) -{ - struct sctp_ht_iter *iter = seq->private; - - rhashtable_walk_stop(&iter->hti); - rhashtable_walk_exit(&iter->hti); -} - static void *sctp_assocs_seq_start(struct seq_file *seq, loff_t *pos) { - int err = sctp_transport_walk_start(seq); + struct sctp_ht_iter *iter = seq->private; + int err = sctp_transport_walk_start(&iter->hti); if (err) return ERR_PTR(err); - return sctp_transport_get_idx(seq, *pos); + return sctp_transport_get_idx(seq_file_net(seq), &iter->hti, *pos); } static void sctp_assocs_seq_stop(struct seq_file *seq, void *v) { - sctp_transport_walk_stop(seq); + struct sctp_ht_iter *iter = seq->private; + + sctp_transport_walk_stop(&iter->hti); } static void *sctp_assocs_seq_next(struct seq_file *seq, void *v, loff_t *pos) { + struct sctp_ht_iter *iter = seq->private; + ++*pos; - return sctp_transport_get_next(seq); + return sctp_transport_get_next(seq_file_net(seq), &iter->hti); } /* Display sctp associations (/proc/net/sctp/assocs). */ @@ -458,24 +408,29 @@ void sctp_assocs_proc_exit(struct net *net) static void *sctp_remaddr_seq_start(struct seq_file *seq, loff_t *pos) { - int err = sctp_transport_walk_start(seq); + struct sctp_ht_iter *iter = seq->private; + int err = sctp_transport_walk_start(&iter->hti); if (err) return ERR_PTR(err); - return sctp_transport_get_idx(seq, *pos); + return sctp_transport_get_idx(seq_file_net(seq), &iter->hti, *pos); } static void *sctp_remaddr_seq_next(struct seq_file *seq, void *v, loff_t *pos) { + struct sctp_ht_iter *iter = seq->private; + ++*pos; - return sctp_transport_get_next(seq); + return sctp_transport_get_next(seq_file_net(seq), &iter->hti); } static void sctp_remaddr_seq_stop(struct seq_file *seq, void *v) { - sctp_transport_walk_stop(seq); + struct sctp_ht_iter *iter = seq->private; + + sctp_transport_walk_stop(&iter->hti); } static int sctp_remaddr_seq_show(struct seq_file *seq, void *v) diff --git a/net/sctp/socket.c b/net/sctp/socket.c index cd0fb3bb493c..5e5bc08d2b25 100644 --- a/net/sctp/socket.c +++ b/net/sctp/socket.c @@ -4288,6 +4288,131 @@ int sctp_get_sctp_info(struct sock *sk, struct sctp_association *asoc, } EXPORT_SYMBOL_GPL(sctp_get_sctp_info); +/* use callback to avoid exporting the core structure */ +int sctp_transport_walk_start(struct rhashtable_iter *iter) +{ + int err; + + err = rhashtable_walk_init(&sctp_transport_hashtable, iter, + GFP_KERNEL); + if (err) + return err; + + err = rhashtable_walk_start(iter); + + return err == -EAGAIN ? 0 : err; +} + +void sctp_transport_walk_stop(struct rhashtable_iter *iter) +{ + rhashtable_walk_stop(iter); + rhashtable_walk_exit(iter); +} + +struct sctp_transport *sctp_transport_get_next(struct net *net, + struct rhashtable_iter *iter) +{ + struct sctp_transport *t; + + t = rhashtable_walk_next(iter); + for (; t; t = rhashtable_walk_next(iter)) { + if (IS_ERR(t)) { + if (PTR_ERR(t) == -EAGAIN) + continue; + break; + } + + if (net_eq(sock_net(t->asoc->base.sk), net) && + t->asoc->peer.primary_path == t) + break; + } + + return t; +} + +struct sctp_transport *sctp_transport_get_idx(struct net *net, + struct rhashtable_iter *iter, + int pos) +{ + void *obj = SEQ_START_TOKEN; + + while (pos && (obj = sctp_transport_get_next(net, iter)) && + !IS_ERR(obj)) + pos--; + + return obj; +} + +int sctp_for_each_endpoint(int (*cb)(struct sctp_endpoint *, void *), + void *p) { + int err = 0; + int hash = 0; + struct sctp_ep_common *epb; + struct sctp_hashbucket *head; + + for (head = sctp_ep_hashtable; hash < sctp_ep_hashsize; + hash++, head++) { + read_lock(&head->lock); + sctp_for_each_hentry(epb, &head->chain) { + err = cb(sctp_ep(epb), p); + if (err) + break; + } + read_unlock(&head->lock); + } + + return err; +} +EXPORT_SYMBOL_GPL(sctp_for_each_endpoint); + +int sctp_transport_lookup_process(int (*cb)(struct sctp_transport *, void *), + struct net *net, + const union sctp_addr *laddr, + const union sctp_addr *paddr, void *p) +{ + struct sctp_transport *transport; + int err = 0; + + rcu_read_lock(); + transport = sctp_addrs_lookup_transport(net, laddr, paddr); + if (!transport || !sctp_transport_hold(transport)) + goto out; + err = cb(transport, p); + sctp_transport_put(transport); + +out: + rcu_read_unlock(); + return err; +} +EXPORT_SYMBOL_GPL(sctp_transport_lookup_process); + +int sctp_for_each_transport(int (*cb)(struct sctp_transport *, void *), + struct net *net, int pos, void *p) { + struct rhashtable_iter hti; + int err = 0; + void *obj; + + if (sctp_transport_walk_start(&hti)) + goto out; + + sctp_transport_get_idx(net, &hti, pos); + obj = sctp_transport_get_next(net, &hti); + for (; obj && !IS_ERR(obj); obj = sctp_transport_get_next(net, &hti)) { + struct sctp_transport *transport = obj; + + if (!sctp_transport_hold(transport)) + continue; + err = cb(transport, p); + sctp_transport_put(transport); + if (err) + break; + } +out: + sctp_transport_walk_stop(&hti); + return err; +} +EXPORT_SYMBOL_GPL(sctp_for_each_transport); + /* 7.2.1 Association Status (SCTP_STATUS) * Applications can retrieve current status information about an -- cgit v1.2.3 From b5e2f4e6998a2b999da8fa0290b692f0bd85c8b7 Mon Sep 17 00:00:00 2001 From: Xin Long Date: Thu, 14 Apr 2016 15:35:34 +0800 Subject: sctp: merge the seq_start/next/exits in remaddrs and assocs In sctp proc, these three functions in remaddrs and assocs are the same. we should merge them into one. Signed-off-by: Xin Long Signed-off-by: David S. Miller --- net/sctp/proc.c | 45 +++++++++------------------------------------ 1 file changed, 9 insertions(+), 36 deletions(-) (limited to 'net/sctp/proc.c') diff --git a/net/sctp/proc.c b/net/sctp/proc.c index dd8492f0037d..9fe139368ad7 100644 --- a/net/sctp/proc.c +++ b/net/sctp/proc.c @@ -282,7 +282,7 @@ struct sctp_ht_iter { struct rhashtable_iter hti; }; -static void *sctp_assocs_seq_start(struct seq_file *seq, loff_t *pos) +static void *sctp_transport_seq_start(struct seq_file *seq, loff_t *pos) { struct sctp_ht_iter *iter = seq->private; int err = sctp_transport_walk_start(&iter->hti); @@ -293,14 +293,14 @@ static void *sctp_assocs_seq_start(struct seq_file *seq, loff_t *pos) return sctp_transport_get_idx(seq_file_net(seq), &iter->hti, *pos); } -static void sctp_assocs_seq_stop(struct seq_file *seq, void *v) +static void sctp_transport_seq_stop(struct seq_file *seq, void *v) { struct sctp_ht_iter *iter = seq->private; sctp_transport_walk_stop(&iter->hti); } -static void *sctp_assocs_seq_next(struct seq_file *seq, void *v, loff_t *pos) +static void *sctp_transport_seq_next(struct seq_file *seq, void *v, loff_t *pos) { struct sctp_ht_iter *iter = seq->private; @@ -367,9 +367,9 @@ static int sctp_assocs_seq_show(struct seq_file *seq, void *v) } static const struct seq_operations sctp_assoc_ops = { - .start = sctp_assocs_seq_start, - .next = sctp_assocs_seq_next, - .stop = sctp_assocs_seq_stop, + .start = sctp_transport_seq_start, + .next = sctp_transport_seq_next, + .stop = sctp_transport_seq_stop, .show = sctp_assocs_seq_show, }; @@ -406,33 +406,6 @@ void sctp_assocs_proc_exit(struct net *net) remove_proc_entry("assocs", net->sctp.proc_net_sctp); } -static void *sctp_remaddr_seq_start(struct seq_file *seq, loff_t *pos) -{ - struct sctp_ht_iter *iter = seq->private; - int err = sctp_transport_walk_start(&iter->hti); - - if (err) - return ERR_PTR(err); - - return sctp_transport_get_idx(seq_file_net(seq), &iter->hti, *pos); -} - -static void *sctp_remaddr_seq_next(struct seq_file *seq, void *v, loff_t *pos) -{ - struct sctp_ht_iter *iter = seq->private; - - ++*pos; - - return sctp_transport_get_next(seq_file_net(seq), &iter->hti); -} - -static void sctp_remaddr_seq_stop(struct seq_file *seq, void *v) -{ - struct sctp_ht_iter *iter = seq->private; - - sctp_transport_walk_stop(&iter->hti); -} - static int sctp_remaddr_seq_show(struct seq_file *seq, void *v) { struct sctp_association *assoc; @@ -506,9 +479,9 @@ static int sctp_remaddr_seq_show(struct seq_file *seq, void *v) } static const struct seq_operations sctp_remaddr_ops = { - .start = sctp_remaddr_seq_start, - .next = sctp_remaddr_seq_next, - .stop = sctp_remaddr_seq_stop, + .start = sctp_transport_seq_start, + .next = sctp_transport_seq_next, + .stop = sctp_transport_seq_stop, .show = sctp_remaddr_seq_show, }; -- cgit v1.2.3 From 53fa10369c45a51947f06e8b622d2fa2cc64fda1 Mon Sep 17 00:00:00 2001 From: Xin Long Date: Thu, 14 Apr 2016 15:35:35 +0800 Subject: sctp: fix some rhashtable functions using in sctp proc/diag When rhashtable_walk_init return err, no release function should be called, and when rhashtable_walk_start return err, we should only invoke rhashtable_walk_exit to release the source. But now when sctp_transport_walk_start return err, we just call rhashtable_walk_stop/exit, and never care about if rhashtable_walk_init or start return err, which is so bad. We will fix it by calling rhashtable_walk_exit if rhashtable_walk_start return err in sctp_transport_walk_start, and if sctp_transport_walk_start return err, we do not need to call sctp_transport_walk_stop any more. For sctp proc, we will use 'iter->start_fail' to decide if we will call rhashtable_walk_stop/exit. Signed-off-by: Xin Long Signed-off-by: David S. Miller --- net/sctp/proc.c | 7 ++++++- net/sctp/socket.c | 15 ++++++++++----- 2 files changed, 16 insertions(+), 6 deletions(-) (limited to 'net/sctp/proc.c') diff --git a/net/sctp/proc.c b/net/sctp/proc.c index 9fe139368ad7..4cb5aedfe3ee 100644 --- a/net/sctp/proc.c +++ b/net/sctp/proc.c @@ -280,6 +280,7 @@ void sctp_eps_proc_exit(struct net *net) struct sctp_ht_iter { struct seq_net_private p; struct rhashtable_iter hti; + int start_fail; }; static void *sctp_transport_seq_start(struct seq_file *seq, loff_t *pos) @@ -287,8 +288,10 @@ static void *sctp_transport_seq_start(struct seq_file *seq, loff_t *pos) struct sctp_ht_iter *iter = seq->private; int err = sctp_transport_walk_start(&iter->hti); - if (err) + if (err) { + iter->start_fail = 1; return ERR_PTR(err); + } return sctp_transport_get_idx(seq_file_net(seq), &iter->hti, *pos); } @@ -297,6 +300,8 @@ static void sctp_transport_seq_stop(struct seq_file *seq, void *v) { struct sctp_ht_iter *iter = seq->private; + if (iter->start_fail) + return; sctp_transport_walk_stop(&iter->hti); } diff --git a/net/sctp/socket.c b/net/sctp/socket.c index 5e5bc08d2b25..777d0324594a 100644 --- a/net/sctp/socket.c +++ b/net/sctp/socket.c @@ -4299,8 +4299,12 @@ int sctp_transport_walk_start(struct rhashtable_iter *iter) return err; err = rhashtable_walk_start(iter); + if (err && err != -EAGAIN) { + rhashtable_walk_exit(iter); + return err; + } - return err == -EAGAIN ? 0 : err; + return 0; } void sctp_transport_walk_stop(struct rhashtable_iter *iter) @@ -4389,11 +4393,12 @@ EXPORT_SYMBOL_GPL(sctp_transport_lookup_process); int sctp_for_each_transport(int (*cb)(struct sctp_transport *, void *), struct net *net, int pos, void *p) { struct rhashtable_iter hti; - int err = 0; void *obj; + int err; - if (sctp_transport_walk_start(&hti)) - goto out; + err = sctp_transport_walk_start(&hti); + if (err) + return err; sctp_transport_get_idx(net, &hti, pos); obj = sctp_transport_get_next(net, &hti); @@ -4407,8 +4412,8 @@ int sctp_for_each_transport(int (*cb)(struct sctp_transport *, void *), if (err) break; } -out: sctp_transport_walk_stop(&hti); + return err; } EXPORT_SYMBOL_GPL(sctp_for_each_transport); -- cgit v1.2.3