int netfs_trans_send(struct netfs_trans *t, struct netfs_state *st)
{
int err;
struct msghdr msg;
BUG_ON(!t->iovec.iov_len);
BUG_ON(t->iovec.iov_len > 1024*1024*1024);
netfs_state_lock_send(st);
if (!st->socket) {
err = netfs_state_init(st);
if (err)
goto err_out_unlock_return;
}
msg.msg_iov = &t->iovec;
msg.msg_iovlen = 1;
msg.msg_name = NULL;
msg.msg_namelen = 0;
msg.msg_control = NULL;
msg.msg_controllen = 0;
msg.msg_flags = MSG_WAITALL;
if (t->attached_pages)
msg.msg_flags |= MSG_MORE;
err = kernel_sendmsg(st->socket, &msg, (struct kvec *)msg.msg_iov, 1, t->iovec.iov_len);
if (err <= 0) {
printk("%s: failed to send contig transaction: t: %p, gen: %u, size: %zu, err: %d.\n",
__func__, t, t->gen, t->iovec.iov_len, err);
if (err == 0)
err = -ECONNRESET;
goto err_out_unlock_return;
}
dprintk("%s: sent %s transaction: t: %p, gen: %u, size: %zu, page_num: %u.\n",
__func__, (t->page_num)?"partial":"full",
t, t->gen, t->iovec.iov_len, t->page_num);
err = 0;
if (t->attached_pages)
err = netfs_trans_send_pages(t, st);
err_out_unlock_return:
if (st->need_reset)
netfs_state_exit(st);
netfs_state_unlock_send(st);
dprintk("%s: t: %p, gen: %u, err: %d.\n",
__func__, t, t->gen, err);
t->result = err;
return err;
}
static int netfs_trans_send_pages(struct netfs_trans *t, struct netfs_state *st)
{
int err = 0;
unsigned int i, attached_pages = t->attached_pages, ci;
struct msghdr msg;
struct page **pages = (t->eng)?t->eng->pages:t->pages;
struct page *p;
unsigned int size;
msg.msg_name = NULL;
msg.msg_namelen = 0;
msg.msg_control = NULL;
msg.msg_controllen = 0;
msg.msg_flags = MSG_WAITALL | MSG_MORE;
ci = 0;
for (i=0; i<t->page_num; ++i) {
struct page *page = pages[ci];
struct netfs_cmd cmd;
struct iovec io;
p = t->pages[i];
if (!p)
continue;
size = page_private(p);
io.iov_base = &cmd;
io.iov_len = sizeof(struct netfs_cmd);
cmd.cmd = NETFS_WRITE_PAGE;
cmd.ext = 0;
cmd.id = 0;
cmd.size = size;
cmd.start = p->index;
cmd.start <<= PAGE_CACHE_SHIFT;
cmd.csize = 0;
cmd.cpad = 0;
cmd.iv = pohmelfs_gen_iv(t);
netfs_convert_cmd(&cmd);
msg.msg_iov = &io;
msg.msg_iovlen = 1;
msg.msg_flags = MSG_WAITALL | MSG_MORE;
err = kernel_sendmsg(st->socket, &msg, (struct kvec *)msg.msg_iov, 1, sizeof(struct netfs_cmd));
if (err <= 0) {
printk("%s: %d/%d failed to send transaction header: t: %p, gen: %u, err: %d.\n",
__func__, i, t->page_num, t, t->gen, err);
if (err == 0)
err = -ECONNRESET;
goto err_out;
}
msg.msg_flags = MSG_WAITALL | (attached_pages == 1 ? 0 :
MSG_MORE);
err = kernel_sendpage(st->socket, page, 0, size, msg.msg_flags);
if (err <= 0) {
printk("%s: %d/%d failed to send transaction page: t: %p, gen: %u, size: %u, err: %d.\n",
__func__, i, t->page_num, t, t->gen, size, err);
if (err == 0)
err = -ECONNRESET;
goto err_out;
}
dprintk("%s: %d/%d sent t: %p, gen: %u, page: %p/%p, size: %u.\n",
__func__, i, t->page_num, t, t->gen, page, p, size);
err = 0;
attached_pages--;
if (!attached_pages)
break;
ci++;
continue;
err_out:
printk("%s: t: %p, gen: %u, err: %d.\n", __func__, t, t->gen, err);
netfs_state_exit(st);
break;
}
return err;
}
static int pohmelfs_data_recv(struct netfs_state *st, void *data, unsigned int size)
{
unsigned int revents = 0;
unsigned int err_mask = POLLERR | POLLHUP | POLLRDHUP;
unsigned int mask = err_mask | POLLIN;
int err = 0;
while (size && !err) {
revents = netfs_state_poll(st);
if (!(revents & mask)) {
DEFINE_WAIT(wait);
for (;;) {
prepare_to_wait(&st->thread_wait, &wait, TASK_INTERRUPTIBLE);
if (kthread_should_stop())
break;
revents = netfs_state_poll(st);
if (revents & mask)
break;
if (signal_pending(current))
break;
schedule();
continue;
}
finish_wait(&st->thread_wait, &wait);
}
err = 0;
netfs_state_lock(st);
if (st->socket && (st->read_socket == st->socket) && (revents & POLLIN)) {
err = netfs_data_recv(st, data, size);
if (err > 0) {
data += err;
size -= err;
err = 0;
} else if (err == 0)
err = -ECONNRESET;
}
if (revents & err_mask) {
printk("%s: revents: %x, socket: %p, size: %u, err: %d.\n",
__func__, revents, st->socket, size, err);
err = -ECONNRESET;
}
netfs_state_unlock(st);
if (err < 0) {
if (netfs_state_trylock_send(st)) {
netfs_state_exit(st);
err = netfs_state_init(st);
if (!err)
err = -EAGAIN;
netfs_state_unlock_send(st);
} else {
st->need_reset = 1;
}
}
if (kthread_should_stop())
err = -ENODEV;
if (err)
printk("%s: socket: %p, read_socket: %p, revents: %x, rev_error: %d, "
"should_stop: %d, size: %u, err: %d.\n",
__func__, st->socket, st->read_socket,
revents, revents & err_mask, kthread_should_stop(), size, err);
}
return err;
}