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-rw-r--r--net/core/skmsg.c802
1 files changed, 802 insertions, 0 deletions
diff --git a/net/core/skmsg.c b/net/core/skmsg.c
new file mode 100644
index 000000000000..56a99d0c9aa0
--- /dev/null
+++ b/net/core/skmsg.c
@@ -0,0 +1,802 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2017 - 2018 Covalent IO, Inc. http://covalent.io */
+
+#include <linux/skmsg.h>
+#include <linux/skbuff.h>
+#include <linux/scatterlist.h>
+
+#include <net/sock.h>
+#include <net/tcp.h>
+
+static bool sk_msg_try_coalesce_ok(struct sk_msg *msg, int elem_first_coalesce)
+{
+ if (msg->sg.end > msg->sg.start &&
+ elem_first_coalesce < msg->sg.end)
+ return true;
+
+ if (msg->sg.end < msg->sg.start &&
+ (elem_first_coalesce > msg->sg.start ||
+ elem_first_coalesce < msg->sg.end))
+ return true;
+
+ return false;
+}
+
+int sk_msg_alloc(struct sock *sk, struct sk_msg *msg, int len,
+ int elem_first_coalesce)
+{
+ struct page_frag *pfrag = sk_page_frag(sk);
+ int ret = 0;
+
+ len -= msg->sg.size;
+ while (len > 0) {
+ struct scatterlist *sge;
+ u32 orig_offset;
+ int use, i;
+
+ if (!sk_page_frag_refill(sk, pfrag))
+ return -ENOMEM;
+
+ orig_offset = pfrag->offset;
+ use = min_t(int, len, pfrag->size - orig_offset);
+ if (!sk_wmem_schedule(sk, use))
+ return -ENOMEM;
+
+ i = msg->sg.end;
+ sk_msg_iter_var_prev(i);
+ sge = &msg->sg.data[i];
+
+ if (sk_msg_try_coalesce_ok(msg, elem_first_coalesce) &&
+ sg_page(sge) == pfrag->page &&
+ sge->offset + sge->length == orig_offset) {
+ sge->length += use;
+ } else {
+ if (sk_msg_full(msg)) {
+ ret = -ENOSPC;
+ break;
+ }
+
+ sge = &msg->sg.data[msg->sg.end];
+ sg_unmark_end(sge);
+ sg_set_page(sge, pfrag->page, use, orig_offset);
+ get_page(pfrag->page);
+ sk_msg_iter_next(msg, end);
+ }
+
+ sk_mem_charge(sk, use);
+ msg->sg.size += use;
+ pfrag->offset += use;
+ len -= use;
+ }
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(sk_msg_alloc);
+
+int sk_msg_clone(struct sock *sk, struct sk_msg *dst, struct sk_msg *src,
+ u32 off, u32 len)
+{
+ int i = src->sg.start;
+ struct scatterlist *sge = sk_msg_elem(src, i);
+ u32 sge_len, sge_off;
+
+ if (sk_msg_full(dst))
+ return -ENOSPC;
+
+ while (off) {
+ if (sge->length > off)
+ break;
+ off -= sge->length;
+ sk_msg_iter_var_next(i);
+ if (i == src->sg.end && off)
+ return -ENOSPC;
+ sge = sk_msg_elem(src, i);
+ }
+
+ while (len) {
+ sge_len = sge->length - off;
+ sge_off = sge->offset + off;
+ if (sge_len > len)
+ sge_len = len;
+ off = 0;
+ len -= sge_len;
+ sk_msg_page_add(dst, sg_page(sge), sge_len, sge_off);
+ sk_mem_charge(sk, sge_len);
+ sk_msg_iter_var_next(i);
+ if (i == src->sg.end && len)
+ return -ENOSPC;
+ sge = sk_msg_elem(src, i);
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(sk_msg_clone);
+
+void sk_msg_return_zero(struct sock *sk, struct sk_msg *msg, int bytes)
+{
+ int i = msg->sg.start;
+
+ do {
+ struct scatterlist *sge = sk_msg_elem(msg, i);
+
+ if (bytes < sge->length) {
+ sge->length -= bytes;
+ sge->offset += bytes;
+ sk_mem_uncharge(sk, bytes);
+ break;
+ }
+
+ sk_mem_uncharge(sk, sge->length);
+ bytes -= sge->length;
+ sge->length = 0;
+ sge->offset = 0;
+ sk_msg_iter_var_next(i);
+ } while (bytes && i != msg->sg.end);
+ msg->sg.start = i;
+}
+EXPORT_SYMBOL_GPL(sk_msg_return_zero);
+
+void sk_msg_return(struct sock *sk, struct sk_msg *msg, int bytes)
+{
+ int i = msg->sg.start;
+
+ do {
+ struct scatterlist *sge = &msg->sg.data[i];
+ int uncharge = (bytes < sge->length) ? bytes : sge->length;
+
+ sk_mem_uncharge(sk, uncharge);
+ bytes -= uncharge;
+ sk_msg_iter_var_next(i);
+ } while (i != msg->sg.end);
+}
+EXPORT_SYMBOL_GPL(sk_msg_return);
+
+static int sk_msg_free_elem(struct sock *sk, struct sk_msg *msg, u32 i,
+ bool charge)
+{
+ struct scatterlist *sge = sk_msg_elem(msg, i);
+ u32 len = sge->length;
+
+ if (charge)
+ sk_mem_uncharge(sk, len);
+ if (!msg->skb)
+ put_page(sg_page(sge));
+ memset(sge, 0, sizeof(*sge));
+ return len;
+}
+
+static int __sk_msg_free(struct sock *sk, struct sk_msg *msg, u32 i,
+ bool charge)
+{
+ struct scatterlist *sge = sk_msg_elem(msg, i);
+ int freed = 0;
+
+ while (msg->sg.size) {
+ msg->sg.size -= sge->length;
+ freed += sk_msg_free_elem(sk, msg, i, charge);
+ sk_msg_iter_var_next(i);
+ sk_msg_check_to_free(msg, i, msg->sg.size);
+ sge = sk_msg_elem(msg, i);
+ }
+ if (msg->skb)
+ consume_skb(msg->skb);
+ sk_msg_init(msg);
+ return freed;
+}
+
+int sk_msg_free_nocharge(struct sock *sk, struct sk_msg *msg)
+{
+ return __sk_msg_free(sk, msg, msg->sg.start, false);
+}
+EXPORT_SYMBOL_GPL(sk_msg_free_nocharge);
+
+int sk_msg_free(struct sock *sk, struct sk_msg *msg)
+{
+ return __sk_msg_free(sk, msg, msg->sg.start, true);
+}
+EXPORT_SYMBOL_GPL(sk_msg_free);
+
+static void __sk_msg_free_partial(struct sock *sk, struct sk_msg *msg,
+ u32 bytes, bool charge)
+{
+ struct scatterlist *sge;
+ u32 i = msg->sg.start;
+
+ while (bytes) {
+ sge = sk_msg_elem(msg, i);
+ if (!sge->length)
+ break;
+ if (bytes < sge->length) {
+ if (charge)
+ sk_mem_uncharge(sk, bytes);
+ sge->length -= bytes;
+ sge->offset += bytes;
+ msg->sg.size -= bytes;
+ break;
+ }
+
+ msg->sg.size -= sge->length;
+ bytes -= sge->length;
+ sk_msg_free_elem(sk, msg, i, charge);
+ sk_msg_iter_var_next(i);
+ sk_msg_check_to_free(msg, i, bytes);
+ }
+ msg->sg.start = i;
+}
+
+void sk_msg_free_partial(struct sock *sk, struct sk_msg *msg, u32 bytes)
+{
+ __sk_msg_free_partial(sk, msg, bytes, true);
+}
+EXPORT_SYMBOL_GPL(sk_msg_free_partial);
+
+void sk_msg_free_partial_nocharge(struct sock *sk, struct sk_msg *msg,
+ u32 bytes)
+{
+ __sk_msg_free_partial(sk, msg, bytes, false);
+}
+
+void sk_msg_trim(struct sock *sk, struct sk_msg *msg, int len)
+{
+ int trim = msg->sg.size - len;
+ u32 i = msg->sg.end;
+
+ if (trim <= 0) {
+ WARN_ON(trim < 0);
+ return;
+ }
+
+ sk_msg_iter_var_prev(i);
+ msg->sg.size = len;
+ while (msg->sg.data[i].length &&
+ trim >= msg->sg.data[i].length) {
+ trim -= msg->sg.data[i].length;
+ sk_msg_free_elem(sk, msg, i, true);
+ sk_msg_iter_var_prev(i);
+ if (!trim)
+ goto out;
+ }
+
+ msg->sg.data[i].length -= trim;
+ sk_mem_uncharge(sk, trim);
+out:
+ /* If we trim data before curr pointer update copybreak and current
+ * so that any future copy operations start at new copy location.
+ * However trimed data that has not yet been used in a copy op
+ * does not require an update.
+ */
+ if (msg->sg.curr >= i) {
+ msg->sg.curr = i;
+ msg->sg.copybreak = msg->sg.data[i].length;
+ }
+ sk_msg_iter_var_next(i);
+ msg->sg.end = i;
+}
+EXPORT_SYMBOL_GPL(sk_msg_trim);
+
+int sk_msg_zerocopy_from_iter(struct sock *sk, struct iov_iter *from,
+ struct sk_msg *msg, u32 bytes)
+{
+ int i, maxpages, ret = 0, num_elems = sk_msg_elem_used(msg);
+ const int to_max_pages = MAX_MSG_FRAGS;
+ struct page *pages[MAX_MSG_FRAGS];
+ ssize_t orig, copied, use, offset;
+
+ orig = msg->sg.size;
+ while (bytes > 0) {
+ i = 0;
+ maxpages = to_max_pages - num_elems;
+ if (maxpages == 0) {
+ ret = -EFAULT;
+ goto out;
+ }
+
+ copied = iov_iter_get_pages(from, pages, bytes, maxpages,
+ &offset);
+ if (copied <= 0) {
+ ret = -EFAULT;
+ goto out;
+ }
+
+ iov_iter_advance(from, copied);
+ bytes -= copied;
+ msg->sg.size += copied;
+
+ while (copied) {
+ use = min_t(int, copied, PAGE_SIZE - offset);
+ sg_set_page(&msg->sg.data[msg->sg.end],
+ pages[i], use, offset);
+ sg_unmark_end(&msg->sg.data[msg->sg.end]);
+ sk_mem_charge(sk, use);
+
+ offset = 0;
+ copied -= use;
+ sk_msg_iter_next(msg, end);
+ num_elems++;
+ i++;
+ }
+ /* When zerocopy is mixed with sk_msg_*copy* operations we
+ * may have a copybreak set in this case clear and prefer
+ * zerocopy remainder when possible.
+ */
+ msg->sg.copybreak = 0;
+ msg->sg.curr = msg->sg.end;
+ }
+out:
+ /* Revert iov_iter updates, msg will need to use 'trim' later if it
+ * also needs to be cleared.
+ */
+ if (ret)
+ iov_iter_revert(from, msg->sg.size - orig);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(sk_msg_zerocopy_from_iter);
+
+int sk_msg_memcopy_from_iter(struct sock *sk, struct iov_iter *from,
+ struct sk_msg *msg, u32 bytes)
+{
+ int ret = -ENOSPC, i = msg->sg.curr;
+ struct scatterlist *sge;
+ u32 copy, buf_size;
+ void *to;
+
+ do {
+ sge = sk_msg_elem(msg, i);
+ /* This is possible if a trim operation shrunk the buffer */
+ if (msg->sg.copybreak >= sge->length) {
+ msg->sg.copybreak = 0;
+ sk_msg_iter_var_next(i);
+ if (i == msg->sg.end)
+ break;
+ sge = sk_msg_elem(msg, i);
+ }
+
+ buf_size = sge->length - msg->sg.copybreak;
+ copy = (buf_size > bytes) ? bytes : buf_size;
+ to = sg_virt(sge) + msg->sg.copybreak;
+ msg->sg.copybreak += copy;
+ if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY)
+ ret = copy_from_iter_nocache(to, copy, from);
+ else
+ ret = copy_from_iter(to, copy, from);
+ if (ret != copy) {
+ ret = -EFAULT;
+ goto out;
+ }
+ bytes -= copy;
+ if (!bytes)
+ break;
+ msg->sg.copybreak = 0;
+ sk_msg_iter_var_next(i);
+ } while (i != msg->sg.end);
+out:
+ msg->sg.curr = i;
+ return ret;
+}
+EXPORT_SYMBOL_GPL(sk_msg_memcopy_from_iter);
+
+static int sk_psock_skb_ingress(struct sk_psock *psock, struct sk_buff *skb)
+{
+ struct sock *sk = psock->sk;
+ int copied = 0, num_sge;
+ struct sk_msg *msg;
+
+ msg = kzalloc(sizeof(*msg), __GFP_NOWARN | GFP_ATOMIC);
+ if (unlikely(!msg))
+ return -EAGAIN;
+ if (!sk_rmem_schedule(sk, skb, skb->len)) {
+ kfree(msg);
+ return -EAGAIN;
+ }
+
+ sk_msg_init(msg);
+ num_sge = skb_to_sgvec(skb, msg->sg.data, 0, skb->len);
+ if (unlikely(num_sge < 0)) {
+ kfree(msg);
+ return num_sge;
+ }
+
+ sk_mem_charge(sk, skb->len);
+ copied = skb->len;
+ msg->sg.start = 0;
+ msg->sg.end = num_sge == MAX_MSG_FRAGS ? 0 : num_sge;
+ msg->skb = skb;
+
+ sk_psock_queue_msg(psock, msg);
+ sk->sk_data_ready(sk);
+ return copied;
+}
+
+static int sk_psock_handle_skb(struct sk_psock *psock, struct sk_buff *skb,
+ u32 off, u32 len, bool ingress)
+{
+ if (ingress)
+ return sk_psock_skb_ingress(psock, skb);
+ else
+ return skb_send_sock_locked(psock->sk, skb, off, len);
+}
+
+static void sk_psock_backlog(struct work_struct *work)
+{
+ struct sk_psock *psock = container_of(work, struct sk_psock, work);
+ struct sk_psock_work_state *state = &psock->work_state;
+ struct sk_buff *skb;
+ bool ingress;
+ u32 len, off;
+ int ret;
+
+ /* Lock sock to avoid losing sk_socket during loop. */
+ lock_sock(psock->sk);
+ if (state->skb) {
+ skb = state->skb;
+ len = state->len;
+ off = state->off;
+ state->skb = NULL;
+ goto start;
+ }
+
+ while ((skb = skb_dequeue(&psock->ingress_skb))) {
+ len = skb->len;
+ off = 0;
+start:
+ ingress = tcp_skb_bpf_ingress(skb);
+ do {
+ ret = -EIO;
+ if (likely(psock->sk->sk_socket))
+ ret = sk_psock_handle_skb(psock, skb, off,
+ len, ingress);
+ if (ret <= 0) {
+ if (ret == -EAGAIN) {
+ state->skb = skb;
+ state->len = len;
+ state->off = off;
+ goto end;
+ }
+ /* Hard errors break pipe and stop xmit. */
+ sk_psock_report_error(psock, ret ? -ret : EPIPE);
+ sk_psock_clear_state(psock, SK_PSOCK_TX_ENABLED);
+ kfree_skb(skb);
+ goto end;
+ }
+ off += ret;
+ len -= ret;
+ } while (len);
+
+ if (!ingress)
+ kfree_skb(skb);
+ }
+end:
+ release_sock(psock->sk);
+}
+
+struct sk_psock *sk_psock_init(struct sock *sk, int node)
+{
+ struct sk_psock *psock = kzalloc_node(sizeof(*psock),
+ GFP_ATOMIC | __GFP_NOWARN,
+ node);
+ if (!psock)
+ return NULL;
+
+ psock->sk = sk;
+ psock->eval = __SK_NONE;
+
+ INIT_LIST_HEAD(&psock->link);
+ spin_lock_init(&psock->link_lock);
+
+ INIT_WORK(&psock->work, sk_psock_backlog);
+ INIT_LIST_HEAD(&psock->ingress_msg);
+ skb_queue_head_init(&psock->ingress_skb);
+
+ sk_psock_set_state(psock, SK_PSOCK_TX_ENABLED);
+ refcount_set(&psock->refcnt, 1);
+
+ rcu_assign_sk_user_data(sk, psock);
+ sock_hold(sk);
+
+ return psock;
+}
+EXPORT_SYMBOL_GPL(sk_psock_init);
+
+struct sk_psock_link *sk_psock_link_pop(struct sk_psock *psock)
+{
+ struct sk_psock_link *link;
+
+ spin_lock_bh(&psock->link_lock);
+ link = list_first_entry_or_null(&psock->link, struct sk_psock_link,
+ list);
+ if (link)
+ list_del(&link->list);
+ spin_unlock_bh(&psock->link_lock);
+ return link;
+}
+
+void __sk_psock_purge_ingress_msg(struct sk_psock *psock)
+{
+ struct sk_msg *msg, *tmp;
+
+ list_for_each_entry_safe(msg, tmp, &psock->ingress_msg, list) {
+ list_del(&msg->list);
+ sk_msg_free(psock->sk, msg);
+ kfree(msg);
+ }
+}
+
+static void sk_psock_zap_ingress(struct sk_psock *psock)
+{
+ __skb_queue_purge(&psock->ingress_skb);
+ __sk_psock_purge_ingress_msg(psock);
+}
+
+static void sk_psock_link_destroy(struct sk_psock *psock)
+{
+ struct sk_psock_link *link, *tmp;
+
+ list_for_each_entry_safe(link, tmp, &psock->link, list) {
+ list_del(&link->list);
+ sk_psock_free_link(link);
+ }
+}
+
+static void sk_psock_destroy_deferred(struct work_struct *gc)
+{
+ struct sk_psock *psock = container_of(gc, struct sk_psock, gc);
+
+ /* No sk_callback_lock since already detached. */
+ if (psock->parser.enabled)
+ strp_done(&psock->parser.strp);
+
+ cancel_work_sync(&psock->work);
+
+ psock_progs_drop(&psock->progs);
+
+ sk_psock_link_destroy(psock);
+ sk_psock_cork_free(psock);
+ sk_psock_zap_ingress(psock);
+
+ if (psock->sk_redir)
+ sock_put(psock->sk_redir);
+ sock_put(psock->sk);
+ kfree(psock);
+}
+
+void sk_psock_destroy(struct rcu_head *rcu)
+{
+ struct sk_psock *psock = container_of(rcu, struct sk_psock, rcu);
+
+ INIT_WORK(&psock->gc, sk_psock_destroy_deferred);
+ schedule_work(&psock->gc);
+}
+EXPORT_SYMBOL_GPL(sk_psock_destroy);
+
+void sk_psock_drop(struct sock *sk, struct sk_psock *psock)
+{
+ rcu_assign_sk_user_data(sk, NULL);
+ sk_psock_cork_free(psock);
+ sk_psock_restore_proto(sk, psock);
+
+ write_lock_bh(&sk->sk_callback_lock);
+ if (psock->progs.skb_parser)
+ sk_psock_stop_strp(sk, psock);
+ write_unlock_bh(&sk->sk_callback_lock);
+ sk_psock_clear_state(psock, SK_PSOCK_TX_ENABLED);
+
+ call_rcu_sched(&psock->rcu, sk_psock_destroy);
+}
+EXPORT_SYMBOL_GPL(sk_psock_drop);
+
+static int sk_psock_map_verd(int verdict, bool redir)
+{
+ switch (verdict) {
+ case SK_PASS:
+ return redir ? __SK_REDIRECT : __SK_PASS;
+ case SK_DROP:
+ default:
+ break;
+ }
+
+ return __SK_DROP;
+}
+
+int sk_psock_msg_verdict(struct sock *sk, struct sk_psock *psock,
+ struct sk_msg *msg)
+{
+ struct bpf_prog *prog;
+ int ret;
+
+ preempt_disable();
+ rcu_read_lock();
+ prog = READ_ONCE(psock->progs.msg_parser);
+ if (unlikely(!prog)) {
+ ret = __SK_PASS;
+ goto out;
+ }
+
+ sk_msg_compute_data_pointers(msg);
+ msg->sk = sk;
+ ret = BPF_PROG_RUN(prog, msg);
+ ret = sk_psock_map_verd(ret, msg->sk_redir);
+ psock->apply_bytes = msg->apply_bytes;
+ if (ret == __SK_REDIRECT) {
+ if (psock->sk_redir)
+ sock_put(psock->sk_redir);
+ psock->sk_redir = msg->sk_redir;
+ if (!psock->sk_redir) {
+ ret = __SK_DROP;
+ goto out;
+ }
+ sock_hold(psock->sk_redir);
+ }
+out:
+ rcu_read_unlock();
+ preempt_enable();
+ return ret;
+}
+EXPORT_SYMBOL_GPL(sk_psock_msg_verdict);
+
+static int sk_psock_bpf_run(struct sk_psock *psock, struct bpf_prog *prog,
+ struct sk_buff *skb)
+{
+ int ret;
+
+ skb->sk = psock->sk;
+ bpf_compute_data_end_sk_skb(skb);
+ preempt_disable();
+ ret = BPF_PROG_RUN(prog, skb);
+ preempt_enable();
+ /* strparser clones the skb before handing it to a upper layer,
+ * meaning skb_orphan has been called. We NULL sk on the way out
+ * to ensure we don't trigger a BUG_ON() in skb/sk operations
+ * later and because we are not charging the memory of this skb
+ * to any socket yet.
+ */
+ skb->sk = NULL;
+ return ret;
+}
+
+static struct sk_psock *sk_psock_from_strp(struct strparser *strp)
+{
+ struct sk_psock_parser *parser;
+
+ parser = container_of(strp, struct sk_psock_parser, strp);
+ return container_of(parser, struct sk_psock, parser);
+}
+
+static void sk_psock_verdict_apply(struct sk_psock *psock,
+ struct sk_buff *skb, int verdict)
+{
+ struct sk_psock *psock_other;
+ struct sock *sk_other;
+ bool ingress;
+
+ switch (verdict) {
+ case __SK_REDIRECT:
+ sk_other = tcp_skb_bpf_redirect_fetch(skb);
+ if (unlikely(!sk_other))
+ goto out_free;
+ psock_other = sk_psock(sk_other);
+ if (!psock_other || sock_flag(sk_other, SOCK_DEAD) ||
+ !sk_psock_test_state(psock_other, SK_PSOCK_TX_ENABLED))
+ goto out_free;
+ ingress = tcp_skb_bpf_ingress(skb);
+ if ((!ingress && sock_writeable(sk_other)) ||
+ (ingress &&
+ atomic_read(&sk_other->sk_rmem_alloc) <=
+ sk_other->sk_rcvbuf)) {
+ if (!ingress)
+ skb_set_owner_w(skb, sk_other);
+ skb_queue_tail(&psock_other->ingress_skb, skb);
+ schedule_work(&psock_other->work);
+ break;
+ }
+ /* fall-through */
+ case __SK_DROP:
+ /* fall-through */
+ default:
+out_free:
+ kfree_skb(skb);
+ }
+}
+
+static void sk_psock_strp_read(struct strparser *strp, struct sk_buff *skb)
+{
+ struct sk_psock *psock = sk_psock_from_strp(strp);
+ struct bpf_prog *prog;
+ int ret = __SK_DROP;
+
+ rcu_read_lock();
+ prog = READ_ONCE(psock->progs.skb_verdict);
+ if (likely(prog)) {
+ skb_orphan(skb);
+ tcp_skb_bpf_redirect_clear(skb);
+ ret = sk_psock_bpf_run(psock, prog, skb);
+ ret = sk_psock_map_verd(ret, tcp_skb_bpf_redirect_fetch(skb));
+ }
+ rcu_read_unlock();
+ sk_psock_verdict_apply(psock, skb, ret);
+}
+
+static int sk_psock_strp_read_done(struct strparser *strp, int err)
+{
+ return err;
+}
+
+static int sk_psock_strp_parse(struct strparser *strp, struct sk_buff *skb)
+{
+ struct sk_psock *psock = sk_psock_from_strp(strp);
+ struct bpf_prog *prog;
+ int ret = skb->len;
+
+ rcu_read_lock();
+ prog = READ_ONCE(psock->progs.skb_parser);
+ if (likely(prog))
+ ret = sk_psock_bpf_run(psock, prog, skb);
+ rcu_read_unlock();
+ return ret;
+}
+
+/* Called with socket lock held. */
+static void sk_psock_data_ready(struct sock *sk)
+{
+ struct sk_psock *psock;
+
+ rcu_read_lock();
+ psock = sk_psock(sk);
+ if (likely(psock)) {
+ write_lock_bh(&sk->sk_callback_lock);
+ strp_data_ready(&psock->parser.strp);
+ write_unlock_bh(&sk->sk_callback_lock);
+ }
+ rcu_read_unlock();
+}
+
+static void sk_psock_write_space(struct sock *sk)
+{
+ struct sk_psock *psock;
+ void (*write_space)(struct sock *sk);
+
+ rcu_read_lock();
+ psock = sk_psock(sk);
+ if (likely(psock && sk_psock_test_state(psock, SK_PSOCK_TX_ENABLED)))
+ schedule_work(&psock->work);
+ write_space = psock->saved_write_space;
+ rcu_read_unlock();
+ write_space(sk);
+}
+
+int sk_psock_init_strp(struct sock *sk, struct sk_psock *psock)
+{
+ static const struct strp_callbacks cb = {
+ .rcv_msg = sk_psock_strp_read,
+ .read_sock_done = sk_psock_strp_read_done,
+ .parse_msg = sk_psock_strp_parse,
+ };
+
+ psock->parser.enabled = false;
+ return strp_init(&psock->parser.strp, sk, &cb);
+}
+
+void sk_psock_start_strp(struct sock *sk, struct sk_psock *psock)
+{
+ struct sk_psock_parser *parser = &psock->parser;
+
+ if (parser->enabled)
+ return;
+
+ parser->saved_data_ready = sk->sk_data_ready;
+ sk->sk_data_ready = sk_psock_data_ready;
+ sk->sk_write_space = sk_psock_write_space;
+ parser->enabled = true;
+}
+
+void sk_psock_stop_strp(struct sock *sk, struct sk_psock *psock)
+{
+ struct sk_psock_parser *parser = &psock->parser;
+
+ if (!parser->enabled)
+ return;
+
+ sk->sk_data_ready = parser->saved_data_ready;
+ parser->saved_data_ready = NULL;
+ strp_stop(&parser->strp);
+ parser->enabled = false;
+}