[PATCH RFC 10/10] net: replace page_frag with page_frag_cache

From: Yunsheng Lin
Date: Thu Mar 28 2024 - 09:43:56 EST

Use the newly introduced prepare/commit API to replace
page_frag with page_frag_cache for sk_page_frag().

Signed-off-by: Yunsheng Lin <linyunsheng@xxxxxxxxxx>
---
drivers/net/tun.c | 36 ++++++-----
include/linux/sched.h | 5 +-
include/net/sock.h | 7 ++-
kernel/exit.c | 3 +-
kernel/fork.c | 2 +-
net/core/skbuff.c | 29 +++++----
net/core/skmsg.c | 24 +++++---
net/core/sock.c | 24 ++++----
net/ipv4/ip_output.c | 37 ++++++-----
net/ipv4/tcp.c | 33 +++++-----
net/ipv4/tcp_output.c | 30 +++++----
net/ipv6/ip6_output.c | 37 ++++++-----
net/kcm/kcmsock.c | 28 ++++-----
net/mptcp/protocol.c | 72 ++++++++++++++--------
net/tls/tls_device.c | 139 ++++++++++++++++++++++++------------------
15 files changed, 290 insertions(+), 216 deletions(-)

diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index 0b3f21cba552..a1c9b51e146b 100644
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c
@@ -1598,10 +1598,11 @@ static bool tun_can_build_skb(struct tun_struct *tun, struct tun_file *tfile,
}

static struct sk_buff *__tun_build_skb(struct tun_file *tfile,
- struct page_frag *alloc_frag, char *buf,
+ struct page_frag_cache *alloc_frag,
+ char *buf, unsigned int offset,
int buflen, int len, int pad)
{
- struct sk_buff *skb = build_skb(buf, buflen);
+ struct sk_buff *skb = build_skb(buf + offset, buflen);

if (!skb)
return ERR_PTR(-ENOMEM);
@@ -1609,9 +1610,7 @@ static struct sk_buff *__tun_build_skb(struct tun_file *tfile,
skb_reserve(skb, pad);
skb_put(skb, len);
skb_set_owner_w(skb, tfile->socket.sk);
-
- get_page(alloc_frag->page);
- alloc_frag->offset += buflen;
+ page_frag_alloc_commit(alloc_frag, offset, buflen);

return skb;
}
@@ -1660,9 +1659,10 @@ static struct sk_buff *tun_build_skb(struct tun_struct *tun,
struct virtio_net_hdr *hdr,
int len, int *skb_xdp)
{
- struct page_frag *alloc_frag = &current->task_frag;
+ struct page_frag_cache *alloc_frag = &current->task_frag;
struct bpf_prog *xdp_prog;
int buflen = SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
+ unsigned int offset, size;
char *buf;
size_t copied;
int pad = TUN_RX_PAD;
@@ -1675,14 +1675,13 @@ static struct sk_buff *tun_build_skb(struct tun_struct *tun,
buflen += SKB_DATA_ALIGN(len + pad);
rcu_read_unlock();

- alloc_frag->offset = ALIGN((u64)alloc_frag->offset, SMP_CACHE_BYTES);
- if (unlikely(!skb_page_frag_refill(buflen, alloc_frag, GFP_KERNEL)))
+ size = buflen;
+ buf = page_frag_alloc_prepare_align(alloc_frag, &offset, &size,
+ SMP_CACHE_BYTES, GFP_KERNEL);
+ if (unlikely(!buf))
return ERR_PTR(-ENOMEM);

- buf = (char *)page_address(alloc_frag->page) + alloc_frag->offset;
- copied = copy_page_from_iter(alloc_frag->page,
- alloc_frag->offset + pad,
- len, from);
+ copied = copy_from_iter(buf + offset + pad, len, from);
if (copied != len)
return ERR_PTR(-EFAULT);

@@ -1692,8 +1691,8 @@ static struct sk_buff *tun_build_skb(struct tun_struct *tun,
*/
if (hdr->gso_type || !xdp_prog) {
*skb_xdp = 1;
- return __tun_build_skb(tfile, alloc_frag, buf, buflen, len,
- pad);
+ return __tun_build_skb(tfile, alloc_frag, buf, offset, buflen,
+ len, pad);
}

*skb_xdp = 0;
@@ -1710,13 +1709,12 @@ static struct sk_buff *tun_build_skb(struct tun_struct *tun,

act = bpf_prog_run_xdp(xdp_prog, &xdp);
if (act == XDP_REDIRECT || act == XDP_TX) {
- get_page(alloc_frag->page);
- alloc_frag->offset += buflen;
+ page_frag_alloc_commit(alloc_frag, offset, buflen);
}
err = tun_xdp_act(tun, xdp_prog, &xdp, act);
if (err < 0) {
if (act == XDP_REDIRECT || act == XDP_TX)
- put_page(alloc_frag->page);
+ page_frag_free_va(buf);
goto out;
}

@@ -1731,8 +1729,8 @@ static struct sk_buff *tun_build_skb(struct tun_struct *tun,
rcu_read_unlock();
local_bh_enable();

- return __tun_build_skb(tfile, alloc_frag, buf, buflen, len, pad);
-
+ return __tun_build_skb(tfile, alloc_frag, buf, offset, buflen, len,
+ pad);
out:
rcu_read_unlock();
local_bh_enable();
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 3c2abbc587b4..436642be0867 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -35,7 +35,7 @@
#include <linux/sched/types.h>
#include <linux/signal_types.h>
#include <linux/syscall_user_dispatch_types.h>
-#include <linux/mm_types_task.h>
+#include <linux/mm_types.h>
#include <linux/task_io_accounting.h>
#include <linux/posix-timers_types.h>
#include <linux/restart_block.h>
@@ -45,6 +45,7 @@
#include <linux/rv.h>
#include <linux/livepatch_sched.h>
#include <linux/uidgid_types.h>
+#include <linux/page_frag_cache.h>
#include <asm/kmap_size.h>

/* task_struct member predeclarations (sorted alphabetically): */
@@ -1338,7 +1339,7 @@ struct task_struct {
/* Cache last used pipe for splice(): */
struct pipe_inode_info *splice_pipe;

- struct page_frag task_frag;
+ struct page_frag_cache task_frag;

#ifdef CONFIG_TASK_DELAY_ACCT
struct task_delay_info *delays;
diff --git a/include/net/sock.h b/include/net/sock.h
index 20df93699b60..9d8fb8df1ce9 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -461,7 +461,7 @@ struct sock {
struct sk_buff_head sk_write_queue;
u32 sk_dst_pending_confirm;
u32 sk_pacing_status; /* see enum sk_pacing */
- struct page_frag sk_frag;
+ struct page_frag_cache sk_frag;
struct timer_list sk_timer;

unsigned long sk_pacing_rate; /* bytes per second */
@@ -2560,7 +2560,7 @@ static inline void sk_stream_moderate_sndbuf(struct sock *sk)
* Return: a per task page_frag if context allows that,
* otherwise a per socket one.
*/
-static inline struct page_frag *sk_page_frag(struct sock *sk)
+static inline struct page_frag_cache *sk_page_frag(struct sock *sk)
{
if (sk->sk_use_task_frag)
return &current->task_frag;
@@ -2568,7 +2568,8 @@ static inline struct page_frag *sk_page_frag(struct sock *sk)
return &sk->sk_frag;
}

-bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag);
+void *sk_page_frag_alloc_prepare(struct sock *sk, struct page_frag_cache *pfrag,
+ unsigned int *size, unsigned int *offset);

/*
* Default write policy as shown to user space via poll/select/SIGIO
diff --git a/kernel/exit.c b/kernel/exit.c
index 41a12630cbbc..8203275fd5ff 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -913,8 +913,7 @@ void __noreturn do_exit(long code)
if (tsk->splice_pipe)
free_pipe_info(tsk->splice_pipe);

- if (tsk->task_frag.page)
- put_page(tsk->task_frag.page);
+ page_frag_cache_drain(&tsk->task_frag);

exit_task_stack_account(tsk);

diff --git a/kernel/fork.c b/kernel/fork.c
index 39a5046c2f0b..8e5abc30c47a 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -1158,10 +1158,10 @@ static struct task_struct *dup_task_struct(struct task_struct *orig, int node)
tsk->btrace_seq = 0;
#endif
tsk->splice_pipe = NULL;
- tsk->task_frag.page = NULL;
tsk->wake_q.next = NULL;
tsk->worker_private = NULL;

+ page_frag_cache_init(&tsk->task_frag);
kcov_task_init(tsk);
kmsan_task_create(tsk);
kmap_local_fork(tsk);
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index e6bc0dec7463..88da8c52a121 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -3017,23 +3017,24 @@ static void sock_spd_release(struct splice_pipe_desc *spd, unsigned int i)
put_page(spd->pages[i]);
}

-static struct page *linear_to_page(struct page *page, unsigned int *len,
- unsigned int *offset,
- struct sock *sk)
+static struct page *linear_to_page(struct page_frag_cache *pfrag,
+ struct page *page, unsigned int *offset,
+ unsigned int *len, struct sock *sk)
{
- struct page_frag *pfrag = sk_page_frag(sk);
+ unsigned int new_len, new_offset;
+ void *va;

- if (!sk_page_frag_refill(sk, pfrag))
+ va = sk_page_frag_alloc_prepare(sk, pfrag, &new_offset, &new_len);
+ if (!va)
return NULL;

- *len = min_t(unsigned int, *len, pfrag->size - pfrag->offset);
+ *len = min_t(unsigned int, *len, new_len);

- memcpy(page_address(pfrag->page) + pfrag->offset,
+ memcpy(va + new_offset,
page_address(page) + *offset, *len);
- *offset = pfrag->offset;
- pfrag->offset += *len;
+ *offset = new_offset;

- return pfrag->page;
+ return virt_to_page(va);
}

static bool spd_can_coalesce(const struct splice_pipe_desc *spd,
@@ -3055,19 +3056,23 @@ static bool spd_fill_page(struct splice_pipe_desc *spd,
bool linear,
struct sock *sk)
{
+ struct page_frag_cache *pfrag = sk_page_frag(sk);
+
if (unlikely(spd->nr_pages == MAX_SKB_FRAGS))
return true;

if (linear) {
- page = linear_to_page(page, len, &offset, sk);
+ page = linear_to_page(pfrag, page, &offset, len, sk);
if (!page)
return true;
}
if (spd_can_coalesce(spd, page, offset)) {
spd->partial[spd->nr_pages - 1].len += *len;
+ page_frag_alloc_commit_noref(pfrag, offset, *len);
return false;
}
- get_page(page);
+
+ page_frag_alloc_commit(pfrag, offset, *len);
spd->pages[spd->nr_pages] = page;
spd->partial[spd->nr_pages].len = *len;
spd->partial[spd->nr_pages].offset = offset;
diff --git a/net/core/skmsg.c b/net/core/skmsg.c
index 4d75ef9d24bf..b843083bdd4e 100644
--- a/net/core/skmsg.c
+++ b/net/core/skmsg.c
@@ -27,23 +27,26 @@ static bool sk_msg_try_coalesce_ok(struct sk_msg *msg, int elem_first_coalesce)
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);
+ struct page_frag_cache *pfrag = sk_page_frag(sk);
u32 osize = msg->sg.size;
int ret = 0;

len -= msg->sg.size;
while (len > 0) {
+ unsigned int frag_offset, frag_len;
struct scatterlist *sge;
- u32 orig_offset;
+ struct page *page;
int use, i;
+ void *va;

- if (!sk_page_frag_refill(sk, pfrag)) {
+ va = sk_page_frag_alloc_prepare(sk, pfrag, &frag_offset,
+ &frag_len);
+ if (!va) {
ret = -ENOMEM;
goto msg_trim;
}

- orig_offset = pfrag->offset;
- use = min_t(int, len, pfrag->size - orig_offset);
+ use = min_t(int, len, frag_len);
if (!sk_wmem_schedule(sk, use)) {
ret = -ENOMEM;
goto msg_trim;
@@ -53,10 +56,12 @@ int sk_msg_alloc(struct sock *sk, struct sk_msg *msg, int len,
sk_msg_iter_var_prev(i);
sge = &msg->sg.data[i];

+ page = virt_to_page(va);
if (sk_msg_try_coalesce_ok(msg, elem_first_coalesce) &&
- sg_page(sge) == pfrag->page &&
- sge->offset + sge->length == orig_offset) {
+ sg_page(sge) == page &&
+ sge->offset + sge->length == frag_offset) {
sge->length += use;
+ page_frag_alloc_commit_noref(pfrag, frag_offset, use);
} else {
if (sk_msg_full(msg)) {
ret = -ENOSPC;
@@ -65,14 +70,13 @@ int sk_msg_alloc(struct sock *sk, struct sk_msg *msg, int len,

sge = &msg->sg.data[msg->sg.end];
sg_unmark_end(sge);
- sg_set_page(sge, pfrag->page, use, orig_offset);
- get_page(pfrag->page);
+ sg_set_page(sge, page, use, frag_offset);
+ page_frag_alloc_commit(pfrag, frag_offset, use);
sk_msg_iter_next(msg, end);
}

sk_mem_charge(sk, use);
msg->sg.size += use;
- pfrag->offset += use;
len -= use;
}

diff --git a/net/core/sock.c b/net/core/sock.c
index 43bf3818c19e..e10247783ada 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -2191,10 +2191,7 @@ static void __sk_destruct(struct rcu_head *head)
pr_debug("%s: optmem leakage (%d bytes) detected\n",
__func__, atomic_read(&sk->sk_omem_alloc));

- if (sk->sk_frag.page) {
- put_page(sk->sk_frag.page);
- sk->sk_frag.page = NULL;
- }
+ page_frag_cache_drain(&sk->sk_frag);

/* We do not need to acquire sk->sk_peer_lock, we are the last user. */
put_cred(sk->sk_peer_cred);
@@ -2936,16 +2933,21 @@ bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp)
}
EXPORT_SYMBOL(skb_page_frag_refill);

-bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag)
+void *sk_page_frag_alloc_prepare(struct sock *sk, struct page_frag_cache *pfrag,
+ unsigned int *offset, unsigned int *size)
{
- if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation)))
- return true;
+ void *va;
+
+ *size = 32U;
+ va = page_frag_alloc_prepare(pfrag, offset, size, sk->sk_allocation);
+ if (likely(va))
+ return va;

sk_enter_memory_pressure(sk);
sk_stream_moderate_sndbuf(sk);
- return false;
+ return NULL;
}
-EXPORT_SYMBOL(sk_page_frag_refill);
+EXPORT_SYMBOL(sk_page_frag_alloc_prepare);

void __lock_sock(struct sock *sk)
__releases(&sk->sk_lock.slock)
@@ -3479,8 +3481,8 @@ void sock_init_data_uid(struct socket *sock, struct sock *sk, kuid_t uid)
sk->sk_error_report = sock_def_error_report;
sk->sk_destruct = sock_def_destruct;

- sk->sk_frag.page = NULL;
- sk->sk_frag.offset = 0;
+ page_frag_cache_init(&sk->sk_frag);
+
sk->sk_peek_off = -1;

sk->sk_peer_pid = NULL;
diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c
index 1fe794967211..2e96bf6935e1 100644
--- a/net/ipv4/ip_output.c
+++ b/net/ipv4/ip_output.c
@@ -952,7 +952,7 @@ static int __ip_append_data(struct sock *sk,
struct flowi4 *fl4,
struct sk_buff_head *queue,
struct inet_cork *cork,
- struct page_frag *pfrag,
+ struct page_frag_cache *pfrag,
int getfrag(void *from, char *to, int offset,
int len, int odd, struct sk_buff *skb),
void *from, int length, int transhdrlen,
@@ -1228,31 +1228,40 @@ static int __ip_append_data(struct sock *sk,
wmem_alloc_delta += copy;
} else if (!zc) {
int i = skb_shinfo(skb)->nr_frags;
+ unsigned int frag_offset, frag_size;
+ struct page *page;
+ void *va;

err = -ENOMEM;
- if (!sk_page_frag_refill(sk, pfrag))
+ va = sk_page_frag_alloc_prepare(sk, pfrag, &frag_offset,
+ &frag_size);
+ if (!va)
goto error;

+ page = virt_to_page(va);
skb_zcopy_downgrade_managed(skb);
- if (!skb_can_coalesce(skb, i, pfrag->page,
- pfrag->offset)) {
+ copy = min_t(int, copy, frag_size);
+ if (getfrag(from, va + frag_offset, offset, copy,
+ skb->len, skb) < 0)
+ goto error_efault;
+
+ if (!skb_can_coalesce(skb, i, page, frag_offset)) {
err = -EMSGSIZE;
if (i == MAX_SKB_FRAGS)
goto error;

- __skb_fill_page_desc(skb, i, pfrag->page,
- pfrag->offset, 0);
+ __skb_fill_page_desc(skb, i, page, frag_offset,
+ copy);
skb_shinfo(skb)->nr_frags = ++i;
- get_page(pfrag->page);
+ page_frag_alloc_commit(pfrag, frag_offset,
+ copy);
+ } else {
+ skb_frag_size_add(
+ &skb_shinfo(skb)->frags[i - 1], copy);
+ page_frag_alloc_commit_noref(pfrag, frag_offset,
+ copy);
}
- copy = min_t(int, copy, pfrag->size - pfrag->offset);
- if (getfrag(from,
- page_address(pfrag->page) + pfrag->offset,
- offset, copy, skb->len, skb) < 0)
- goto error_efault;

- pfrag->offset += copy;
- skb_frag_size_add(&skb_shinfo(skb)->frags[i - 1], copy);
skb_len_add(skb, copy);
wmem_alloc_delta += copy;
} else {
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index d20b62d52171..7f01d1a1e0ee 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -1177,13 +1177,17 @@ int tcp_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t size)
if (zc == 0) {
bool merge = true;
int i = skb_shinfo(skb)->nr_frags;
- struct page_frag *pfrag = sk_page_frag(sk);
+ struct page_frag_cache *pfrag = sk_page_frag(sk);
+ unsigned int offset, size;
+ struct page *page;
+ void *va;

- if (!sk_page_frag_refill(sk, pfrag))
+ va = sk_page_frag_alloc_prepare(sk, pfrag, &offset, &size);
+ if (!va)
goto wait_for_space;

- if (!skb_can_coalesce(skb, i, pfrag->page,
- pfrag->offset)) {
+ page = virt_to_page(va);
+ if (!skb_can_coalesce(skb, i, page, offset)) {
if (i >= READ_ONCE(sysctl_max_skb_frags)) {
tcp_mark_push(tp, skb);
goto new_segment;
@@ -1191,7 +1195,7 @@ int tcp_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t size)
merge = false;
}

- copy = min_t(int, copy, pfrag->size - pfrag->offset);
+ copy = min_t(int, copy, size);

if (unlikely(skb_zcopy_pure(skb) || skb_zcopy_managed(skb))) {
if (tcp_downgrade_zcopy_pure(sk, skb))
@@ -1203,22 +1207,19 @@ int tcp_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t size)
if (!copy)
goto wait_for_space;

- err = skb_copy_to_page_nocache(sk, &msg->msg_iter, skb,
- pfrag->page,
- pfrag->offset,
- copy);
+ err = skb_copy_to_va_nocache(sk, &msg->msg_iter, skb,
+ va + offset, copy);
if (err)
goto do_error;

/* Update the skb. */
if (merge) {
skb_frag_size_add(&skb_shinfo(skb)->frags[i - 1], copy);
+ page_frag_alloc_commit_noref(pfrag, offset, copy);
} else {
- skb_fill_page_desc(skb, i, pfrag->page,
- pfrag->offset, copy);
- page_ref_inc(pfrag->page);
+ skb_fill_page_desc(skb, i, page, offset, copy);
+ page_frag_alloc_commit(pfrag, offset, copy);
}
- pfrag->offset += copy;
} else if (zc == MSG_ZEROCOPY) {
/* First append to a fragless skb builds initial
* pure zerocopy skb
@@ -3099,11 +3100,7 @@ int tcp_disconnect(struct sock *sk, int flags)

WARN_ON(inet->inet_num && !icsk->icsk_bind_hash);

- if (sk->sk_frag.page) {
- put_page(sk->sk_frag.page);
- sk->sk_frag.page = NULL;
- sk->sk_frag.offset = 0;
- }
+ page_frag_cache_drain(&sk->sk_frag);
sk_error_report(sk);
return 0;
}
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index e3167ad96567..b41293981066 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -3927,9 +3927,12 @@ static int tcp_send_syn_data(struct sock *sk, struct sk_buff *syn)
struct inet_connection_sock *icsk = inet_csk(sk);
struct tcp_sock *tp = tcp_sk(sk);
struct tcp_fastopen_request *fo = tp->fastopen_req;
- struct page_frag *pfrag = sk_page_frag(sk);
+ struct page_frag_cache *pfrag = sk_page_frag(sk);
+ unsigned int offset, size;
struct sk_buff *syn_data;
int space, err = 0;
+ struct page *page;
+ void *va;

tp->rx_opt.mss_clamp = tp->advmss; /* If MSS is not cached */
if (!tcp_fastopen_cookie_check(sk, &tp->rx_opt.mss_clamp, &fo->cookie))
@@ -3948,30 +3951,33 @@ static int tcp_send_syn_data(struct sock *sk, struct sk_buff *syn)

space = min_t(size_t, space, fo->size);

- if (space &&
- !skb_page_frag_refill(min_t(size_t, space, PAGE_SIZE),
- pfrag, sk->sk_allocation))
- goto fallback;
+ if (space) {
+ size = min_t(size_t, space, PAGE_SIZE);
+ va = page_frag_alloc_prepare(pfrag, &offset, &size,
+ sk->sk_allocation);
+ if (!va)
+ goto fallback;
+ }
+
syn_data = tcp_stream_alloc_skb(sk, sk->sk_allocation, false);
if (!syn_data)
goto fallback;
memcpy(syn_data->cb, syn->cb, sizeof(syn->cb));
if (space) {
- space = min_t(size_t, space, pfrag->size - pfrag->offset);
+ space = min_t(size_t, space, size);
space = tcp_wmem_schedule(sk, space);
}
if (space) {
- space = copy_page_from_iter(pfrag->page, pfrag->offset,
- space, &fo->data->msg_iter);
+ space = _copy_from_iter(va + offset, space,
+ &fo->data->msg_iter);
if (unlikely(!space)) {
tcp_skb_tsorted_anchor_cleanup(syn_data);
kfree_skb(syn_data);
goto fallback;
}
- skb_fill_page_desc(syn_data, 0, pfrag->page,
- pfrag->offset, space);
- page_ref_inc(pfrag->page);
- pfrag->offset += space;
+ page = virt_to_page(va);
+ skb_fill_page_desc(syn_data, 0, page, offset, space);
+ page_frag_alloc_commit(pfrag, offset, space);
skb_len_add(syn_data, space);
skb_zcopy_set(syn_data, fo->uarg, NULL);
}
diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
index b9dd3a66e423..c95dcb04c3b2 100644
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -1404,7 +1404,7 @@ static int __ip6_append_data(struct sock *sk,
struct sk_buff_head *queue,
struct inet_cork_full *cork_full,
struct inet6_cork *v6_cork,
- struct page_frag *pfrag,
+ struct page_frag_cache *pfrag,
int getfrag(void *from, char *to, int offset,
int len, int odd, struct sk_buff *skb),
void *from, size_t length, int transhdrlen,
@@ -1745,32 +1745,41 @@ static int __ip6_append_data(struct sock *sk,
copy = err;
wmem_alloc_delta += copy;
} else if (!zc) {
+ unsigned int frag_offset, frag_size;
int i = skb_shinfo(skb)->nr_frags;
+ struct page *page;
+ void *va;

err = -ENOMEM;
- if (!sk_page_frag_refill(sk, pfrag))
+ va = sk_page_frag_alloc_prepare(sk, pfrag, &frag_offset,
+ &frag_size);
+ if (!va)
goto error;

+ page = virt_to_page(va);
skb_zcopy_downgrade_managed(skb);
- if (!skb_can_coalesce(skb, i, pfrag->page,
- pfrag->offset)) {
+ copy = min_t(int, copy, frag_size);
+ if (getfrag(from, va + frag_offset, offset, copy,
+ skb->len, skb) < 0)
+ goto error_efault;
+
+ if (!skb_can_coalesce(skb, i, page, frag_offset)) {
err = -EMSGSIZE;
if (i == MAX_SKB_FRAGS)
goto error;

- __skb_fill_page_desc(skb, i, pfrag->page,
- pfrag->offset, 0);
+ __skb_fill_page_desc(skb, i, page, frag_offset,
+ copy);
skb_shinfo(skb)->nr_frags = ++i;
- get_page(pfrag->page);
+ page_frag_alloc_commit(pfrag, frag_offset,
+ copy);
+ } else {
+ skb_frag_size_add(
+ &skb_shinfo(skb)->frags[i - 1], copy);
+ page_frag_alloc_commit_noref(pfrag, frag_offset,
+ copy);
}
- copy = min_t(int, copy, pfrag->size - pfrag->offset);
- if (getfrag(from,
- page_address(pfrag->page) + pfrag->offset,
- offset, copy, skb->len, skb) < 0)
- goto error_efault;

- pfrag->offset += copy;
- skb_frag_size_add(&skb_shinfo(skb)->frags[i - 1], copy);
skb->len += copy;
skb->data_len += copy;
skb->truesize += copy;
diff --git a/net/kcm/kcmsock.c b/net/kcm/kcmsock.c
index 2f191e50d4fc..5e64ae32f760 100644
--- a/net/kcm/kcmsock.c
+++ b/net/kcm/kcmsock.c
@@ -803,13 +803,17 @@ static int kcm_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
while (msg_data_left(msg)) {
bool merge = true;
int i = skb_shinfo(skb)->nr_frags;
- struct page_frag *pfrag = sk_page_frag(sk);
+ struct page_frag_cache *pfrag = sk_page_frag(sk);
+ unsigned int offset, size;
+ struct page *page;
+ void *va;

- if (!sk_page_frag_refill(sk, pfrag))
+ va = sk_page_frag_alloc_prepare(sk, pfrag, &offset, &size);
+ if (!va)
goto wait_for_memory;

- if (!skb_can_coalesce(skb, i, pfrag->page,
- pfrag->offset)) {
+ page = virt_to_page(va);
+ if (!skb_can_coalesce(skb, i, page, offset)) {
if (i == MAX_SKB_FRAGS) {
struct sk_buff *tskb;

@@ -850,15 +854,12 @@ static int kcm_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
if (head != skb)
head->truesize += copy;
} else {
- copy = min_t(int, msg_data_left(msg),
- pfrag->size - pfrag->offset);
+ copy = min_t(int, msg_data_left(msg), size);
if (!sk_wmem_schedule(sk, copy))
goto wait_for_memory;

- err = skb_copy_to_page_nocache(sk, &msg->msg_iter, skb,
- pfrag->page,
- pfrag->offset,
- copy);
+ err = skb_copy_to_va_nocache(sk, &msg->msg_iter, skb,
+ va + offset, copy);
if (err)
goto out_error;

@@ -866,13 +867,12 @@ static int kcm_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
if (merge) {
skb_frag_size_add(
&skb_shinfo(skb)->frags[i - 1], copy);
+ page_frag_alloc_commit_noref(pfrag, offset, copy);
} else {
- skb_fill_page_desc(skb, i, pfrag->page,
- pfrag->offset, copy);
- get_page(pfrag->page);
+ skb_fill_page_desc(skb, i, page, offset, copy);
+ page_frag_alloc_commit(pfrag, offset, copy);
}

- pfrag->offset += copy;
}

copied += copy;
diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c
index 3a1967bc7bad..7253e4950feb 100644
--- a/net/mptcp/protocol.c
+++ b/net/mptcp/protocol.c
@@ -957,17 +957,16 @@ static bool mptcp_skb_can_collapse_to(u64 write_seq,
}

/* we can append data to the given data frag if:
- * - there is space available in the backing page_frag
- * - the data frag tail matches the current page_frag free offset
+ * - the data frag tail matches the current page and offset
* - the data frag end sequence number matches the current write seq
*/
static bool mptcp_frag_can_collapse_to(const struct mptcp_sock *msk,
- const struct page_frag *pfrag,
+ const struct page *page,
+ const unsigned int offset,
const struct mptcp_data_frag *df)
{
- return df && pfrag->page == df->page &&
- pfrag->size - pfrag->offset > 0 &&
- pfrag->offset == (df->offset + df->data_len) &&
+ return df && page == df->page &&
+ offset == (df->offset + df->data_len) &&
df->data_seq + df->data_len == msk->write_seq;
}

@@ -1082,30 +1081,35 @@ static void mptcp_enter_memory_pressure(struct sock *sk)
/* ensure we get enough memory for the frag hdr, beyond some minimal amount of
* data
*/
-static bool mptcp_page_frag_refill(struct sock *sk, struct page_frag *pfrag)
+static void *mptcp_page_frag_alloc_prepare(struct sock *sk,
+ struct page_frag_cache *pfrag,
+ unsigned int *offset,
+ unsigned int *size)
{
- if (likely(skb_page_frag_refill(32U + sizeof(struct mptcp_data_frag),
- pfrag, sk->sk_allocation)))
- return true;
+ void *va;
+
+ va = page_frag_alloc_prepare(pfrag, offset, size, sk->sk_allocation);
+ if (likely(va))
+ return va;

mptcp_enter_memory_pressure(sk);
- return false;
+ return NULL;
}

static struct mptcp_data_frag *
-mptcp_carve_data_frag(const struct mptcp_sock *msk, struct page_frag *pfrag,
- int orig_offset)
+mptcp_carve_data_frag(const struct mptcp_sock *msk, struct page *page,
+ unsigned int orig_offset)
{
int offset = ALIGN(orig_offset, sizeof(long));
struct mptcp_data_frag *dfrag;

- dfrag = (struct mptcp_data_frag *)(page_to_virt(pfrag->page) + offset);
+ dfrag = (struct mptcp_data_frag *)(page_to_virt(page) + offset);
dfrag->data_len = 0;
dfrag->data_seq = msk->write_seq;
dfrag->overhead = offset - orig_offset + sizeof(struct mptcp_data_frag);
dfrag->offset = offset + sizeof(struct mptcp_data_frag);
dfrag->already_sent = 0;
- dfrag->page = pfrag->page;
+ dfrag->page = page;

return dfrag;
}
@@ -1788,7 +1792,7 @@ static u32 mptcp_send_limit(const struct sock *sk)
static int mptcp_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
{
struct mptcp_sock *msk = mptcp_sk(sk);
- struct page_frag *pfrag;
+ struct page_frag_cache *pfrag;
size_t copied = 0;
int ret = 0;
long timeo;
@@ -1827,9 +1831,12 @@ static int mptcp_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
while (msg_data_left(msg)) {
int total_ts, frag_truesize = 0;
struct mptcp_data_frag *dfrag;
- bool dfrag_collapsed;
- size_t psize, offset;
+ bool dfrag_collapsed = false;
+ unsigned int offset, size;
+ struct page *page;
+ size_t psize;
u32 copy_limit;
+ void *va;

/* ensure fitting the notsent_lowat() constraint */
copy_limit = mptcp_send_limit(sk);
@@ -1840,12 +1847,23 @@ static int mptcp_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
* page allocator
*/
dfrag = mptcp_pending_tail(sk);
- dfrag_collapsed = mptcp_frag_can_collapse_to(msk, pfrag, dfrag);
+ size = 32U;
+ va = mptcp_page_frag_alloc_prepare(sk, pfrag, &offset, &size);
+ if (!va)
+ goto wait_for_memory;
+
+ page = virt_to_page(va);
+ dfrag_collapsed = mptcp_frag_can_collapse_to(msk, page, offset,
+ dfrag);
if (!dfrag_collapsed) {
- if (!mptcp_page_frag_refill(sk, pfrag))
+ size = 32U + sizeof(struct mptcp_data_frag);
+ va = mptcp_page_frag_alloc_prepare(sk, pfrag, &offset,
+ &size);
+ if (!va)
goto wait_for_memory;

- dfrag = mptcp_carve_data_frag(msk, pfrag, pfrag->offset);
+ page = virt_to_page(va);
+ dfrag = mptcp_carve_data_frag(msk, page, offset);
frag_truesize = dfrag->overhead;
}

@@ -1853,8 +1871,7 @@ static int mptcp_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
* memory accounting will prevent execessive memory usage
* anyway
*/
- offset = dfrag->offset + dfrag->data_len;
- psize = pfrag->size - offset;
+ psize = size - frag_truesize;
psize = min_t(size_t, psize, msg_data_left(msg));
psize = min_t(size_t, psize, copy_limit);
total_ts = psize + frag_truesize;
@@ -1863,7 +1880,7 @@ static int mptcp_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
goto wait_for_memory;

ret = do_copy_data_nocache(sk, psize, &msg->msg_iter,
- page_address(dfrag->page) + offset);
+ va + dfrag->offset + dfrag->data_len);
if (ret)
goto do_error;

@@ -1872,7 +1889,6 @@ static int mptcp_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
copied += psize;
dfrag->data_len += psize;
frag_truesize += psize;
- pfrag->offset += frag_truesize;
WRITE_ONCE(msk->write_seq, msk->write_seq + psize);

/* charge data on mptcp pending queue to the msk socket
@@ -1880,11 +1896,15 @@ static int mptcp_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
*/
sk_wmem_queued_add(sk, frag_truesize);
if (!dfrag_collapsed) {
- get_page(dfrag->page);
+ page_frag_alloc_commit(pfrag, offset, frag_truesize);
list_add_tail(&dfrag->list, &msk->rtx_queue);
if (!msk->first_pending)
WRITE_ONCE(msk->first_pending, dfrag);
+ } else {
+ page_frag_alloc_commit_noref(pfrag, offset,
+ frag_truesize);
}
+
pr_debug("msk=%p dfrag at seq=%llu len=%u sent=%u new=%d", msk,
dfrag->data_seq, dfrag->data_len, dfrag->already_sent,
!dfrag_collapsed);
diff --git a/net/tls/tls_device.c b/net/tls/tls_device.c
index bf8ed36b1ad6..af9cf86b727a 100644
--- a/net/tls/tls_device.c
+++ b/net/tls/tls_device.c
@@ -255,25 +255,43 @@ static void tls_device_resync_tx(struct sock *sk, struct tls_context *tls_ctx,
clear_bit_unlock(TLS_TX_SYNC_SCHED, &tls_ctx->flags);
}

-static void tls_append_frag(struct tls_record_info *record,
- struct page_frag *pfrag,
- int size)
+static void tls_append_pfrag(struct tls_record_info *record,
+ struct page_frag_cache *pfrag, struct page *page,
+ unsigned int offset, unsigned int size)
{
skb_frag_t *frag;

frag = &record->frags[record->num_frags - 1];
- if (skb_frag_page(frag) == pfrag->page &&
- skb_frag_off(frag) + skb_frag_size(frag) == pfrag->offset) {
+ if (skb_frag_page(frag) == page &&
+ skb_frag_off(frag) + skb_frag_size(frag) == offset) {
skb_frag_size_add(frag, size);
+ page_frag_alloc_commit_noref(pfrag, offset, size);
} else {
++frag;
- skb_frag_fill_page_desc(frag, pfrag->page, pfrag->offset,
- size);
+ skb_frag_fill_page_desc(frag, page, offset, size);
++record->num_frags;
- get_page(pfrag->page);
+ page_frag_alloc_commit(pfrag, offset, size);
+ }
+
+ record->len += size;
+}
+
+static void tls_append_page(struct tls_record_info *record, struct page *page,
+ unsigned int offset, unsigned int size)
+{
+ skb_frag_t *frag;
+
+ frag = &record->frags[record->num_frags - 1];
+ if (skb_frag_page(frag) == page &&
+ skb_frag_off(frag) + skb_frag_size(frag) == offset) {
+ skb_frag_size_add(frag, size);
+ } else {
+ ++frag;
+ skb_frag_fill_page_desc(frag, page, offset, size);
+ ++record->num_frags;
+ get_page(page);
}

- pfrag->offset += size;
record->len += size;
}

@@ -314,11 +332,13 @@ static int tls_push_record(struct sock *sk,
static void tls_device_record_close(struct sock *sk,
struct tls_context *ctx,
struct tls_record_info *record,
- struct page_frag *pfrag,
+ struct page_frag_cache *pfrag,
unsigned char record_type)
{
struct tls_prot_info *prot = &ctx->prot_info;
- struct page_frag dummy_tag_frag;
+ unsigned int offset, size;
+ struct page *page;
+ void *va;

/* append tag
* device will fill in the tag, we just need to append a placeholder
@@ -326,13 +346,14 @@ static void tls_device_record_close(struct sock *sk,
* increases frag count)
* if we can't allocate memory now use the dummy page
*/
- if (unlikely(pfrag->size - pfrag->offset < prot->tag_size) &&
- !skb_page_frag_refill(prot->tag_size, pfrag, sk->sk_allocation)) {
- dummy_tag_frag.page = dummy_page;
- dummy_tag_frag.offset = 0;
- pfrag = &dummy_tag_frag;
+ size = prot->tag_size;
+ va = page_frag_alloc_prepare(pfrag, &offset, &size, sk->sk_allocation);
+ if (unlikely(!va)) {
+ tls_append_page(record, dummy_page, 0, prot->tag_size);
+ } else {
+ page = virt_to_page(va);
+ tls_append_pfrag(record, pfrag, page, offset, prot->tag_size);
}
- tls_append_frag(record, pfrag, prot->tag_size);

/* fill prepend */
tls_fill_prepend(ctx, skb_frag_address(&record->frags[0]),
@@ -340,23 +361,34 @@ static void tls_device_record_close(struct sock *sk,
record_type);
}

-static int tls_create_new_record(struct tls_offload_context_tx *offload_ctx,
- struct page_frag *pfrag,
+static int tls_create_new_record(struct sock *sk,
+ struct tls_offload_context_tx *offload_ctx,
+ struct page_frag_cache *pfrag,
size_t prepend_size)
{
struct tls_record_info *record;
+ unsigned int offset, size;
+ struct page *page;
skb_frag_t *frag;
+ void *va;
+
+ size = prepend_size;
+ va = page_frag_alloc_prepare(pfrag, &offset, &size, sk->sk_allocation);
+ if (!va) {
+ READ_ONCE(sk->sk_prot)->enter_memory_pressure(sk);
+ sk_stream_moderate_sndbuf(sk);
+ return -ENOMEM;
+ }

record = kmalloc(sizeof(*record), GFP_KERNEL);
if (!record)
return -ENOMEM;

+ page = virt_to_page(va);
frag = &record->frags[0];
- skb_frag_fill_page_desc(frag, pfrag->page, pfrag->offset,
- prepend_size);
+ skb_frag_fill_page_desc(frag, page, offset, prepend_size);

- get_page(pfrag->page);
- pfrag->offset += prepend_size;
+ page_frag_alloc_commit(pfrag, offset, prepend_size);

record->num_frags = 1;
record->len = prepend_size;
@@ -364,33 +396,21 @@ static int tls_create_new_record(struct tls_offload_context_tx *offload_ctx,
return 0;
}

-static int tls_do_allocation(struct sock *sk,
- struct tls_offload_context_tx *offload_ctx,
- struct page_frag *pfrag,
- size_t prepend_size)
+static void *tls_do_allocation(struct sock *sk,
+ struct tls_offload_context_tx *offload_ctx,
+ struct page_frag_cache *pfrag,
+ size_t prepend_size, unsigned int *offset,
+ unsigned int *size)
{
- int ret;
-
if (!offload_ctx->open_record) {
- if (unlikely(!skb_page_frag_refill(prepend_size, pfrag,
- sk->sk_allocation))) {
- READ_ONCE(sk->sk_prot)->enter_memory_pressure(sk);
- sk_stream_moderate_sndbuf(sk);
- return -ENOMEM;
- }
+ int ret;

- ret = tls_create_new_record(offload_ctx, pfrag, prepend_size);
+ ret = tls_create_new_record(sk, offload_ctx, pfrag, prepend_size);
if (ret)
- return ret;
-
- if (pfrag->size > pfrag->offset)
- return 0;
+ return NULL;
}

- if (!sk_page_frag_refill(sk, pfrag))
- return -ENOMEM;
-
- return 0;
+ return sk_page_frag_alloc_prepare(sk, pfrag, offset, size);
}

static int tls_device_copy_data(void *addr, size_t bytes, struct iov_iter *i)
@@ -427,8 +447,8 @@ static int tls_push_data(struct sock *sk,
struct tls_prot_info *prot = &tls_ctx->prot_info;
struct tls_offload_context_tx *ctx = tls_offload_ctx_tx(tls_ctx);
struct tls_record_info *record;
+ struct page_frag_cache *pfrag;
int tls_push_record_flags;
- struct page_frag *pfrag;
size_t orig_size = size;
u32 max_open_record_len;
bool more = false;
@@ -465,8 +485,13 @@ static int tls_push_data(struct sock *sk,
max_open_record_len = TLS_MAX_PAYLOAD_SIZE +
prot->prepend_size;
do {
- rc = tls_do_allocation(sk, ctx, pfrag, prot->prepend_size);
- if (unlikely(rc)) {
+ unsigned int frag_offset, frag_size;
+ struct page *page;
+ void *va;
+
+ va = tls_do_allocation(sk, ctx, pfrag, prot->prepend_size,
+ &frag_offset, &frag_size);
+ if (unlikely(!va)) {
rc = sk_stream_wait_memory(sk, &timeo);
if (!rc)
continue;
@@ -494,8 +519,7 @@ static int tls_push_data(struct sock *sk,

copy = min_t(size_t, size, max_open_record_len - record->len);
if (copy && (flags & MSG_SPLICE_PAGES)) {
- struct page_frag zc_pfrag;
- struct page **pages = &zc_pfrag.page;
+ struct page **pages = &page;
size_t off;

rc = iov_iter_extract_pages(iter, &pages,
@@ -507,24 +531,23 @@ static int tls_push_data(struct sock *sk,
}
copy = rc;

- if (WARN_ON_ONCE(!sendpage_ok(zc_pfrag.page))) {
+ if (WARN_ON_ONCE(!sendpage_ok(page))) {
iov_iter_revert(iter, copy);
rc = -EIO;
goto handle_error;
}

- zc_pfrag.offset = off;
- zc_pfrag.size = copy;
- tls_append_frag(record, &zc_pfrag, copy);
+ tls_append_page(record, page, off, copy);
} else if (copy) {
- copy = min_t(size_t, copy, pfrag->size - pfrag->offset);
+ copy = min_t(size_t, copy, frag_size);

- rc = tls_device_copy_data(page_address(pfrag->page) +
- pfrag->offset, copy,
- iter);
+ rc = tls_device_copy_data(va + frag_offset, copy, iter);
if (rc)
goto handle_error;
- tls_append_frag(record, pfrag, copy);
+
+ page = virt_to_page(va);
+ tls_append_pfrag(record, pfrag, page, frag_offset,
+ copy);
}

size -= copy;
--
2.33.0