From: Sjur Braendeland Date: Tue, 30 Mar 2010 13:56:26 +0000 (+0000) Subject: net-caif: add CAIF socket implementation X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=e6f95ec8db312491235b4f06343fbd991a82ce20;p=GitHub%2FLineageOS%2Fandroid_kernel_motorola_exynos9610.git net-caif: add CAIF socket implementation Implementation of CAIF sockets for protocol and address family PF_CAIF and AF_CAIF. CAIF socket is connection oriented implementing SOCK_SEQPACKET and SOCK_STREAM interface with supporting blocking and non-blocking mode. Signed-off-by: Sjur Braendeland Signed-off-by: David S. Miller --- diff --git a/net/caif/caif_socket.c b/net/caif/caif_socket.c new file mode 100644 index 000000000000..cdf62b9fefac --- /dev/null +++ b/net/caif/caif_socket.c @@ -0,0 +1,1391 @@ +/* + * Copyright (C) ST-Ericsson AB 2010 + * Author: Sjur Brendeland sjur.brandeland@stericsson.com + * Per Sigmond per.sigmond@stericsson.com + * License terms: GNU General Public License (GPL) version 2 + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include +#include +#include + +MODULE_LICENSE("GPL"); + +#define CHNL_SKT_READ_QUEUE_HIGH 200 +#define CHNL_SKT_READ_QUEUE_LOW 100 + +static int caif_sockbuf_size = 40000; +static atomic_t caif_nr_socks = ATOMIC_INIT(0); + +#define CONN_STATE_OPEN_BIT 1 +#define CONN_STATE_PENDING_BIT 2 +#define CONN_STATE_PEND_DESTROY_BIT 3 +#define CONN_REMOTE_SHUTDOWN_BIT 4 + +#define TX_FLOW_ON_BIT 1 +#define RX_FLOW_ON_BIT 2 + +#define STATE_IS_OPEN(cf_sk) test_bit(CONN_STATE_OPEN_BIT,\ + (void *) &(cf_sk)->conn_state) +#define STATE_IS_REMOTE_SHUTDOWN(cf_sk) test_bit(CONN_REMOTE_SHUTDOWN_BIT,\ + (void *) &(cf_sk)->conn_state) +#define STATE_IS_PENDING(cf_sk) test_bit(CONN_STATE_PENDING_BIT,\ + (void *) &(cf_sk)->conn_state) +#define STATE_IS_PENDING_DESTROY(cf_sk) test_bit(CONN_STATE_PEND_DESTROY_BIT,\ + (void *) &(cf_sk)->conn_state) + +#define SET_STATE_PENDING_DESTROY(cf_sk) set_bit(CONN_STATE_PEND_DESTROY_BIT,\ + (void *) &(cf_sk)->conn_state) +#define SET_STATE_OPEN(cf_sk) set_bit(CONN_STATE_OPEN_BIT,\ + (void *) &(cf_sk)->conn_state) +#define SET_STATE_CLOSED(cf_sk) clear_bit(CONN_STATE_OPEN_BIT,\ + (void *) &(cf_sk)->conn_state) +#define SET_PENDING_ON(cf_sk) set_bit(CONN_STATE_PENDING_BIT,\ + (void *) &(cf_sk)->conn_state) +#define SET_PENDING_OFF(cf_sk) clear_bit(CONN_STATE_PENDING_BIT,\ + (void *) &(cf_sk)->conn_state) +#define SET_REMOTE_SHUTDOWN(cf_sk) set_bit(CONN_REMOTE_SHUTDOWN_BIT,\ + (void *) &(cf_sk)->conn_state) + +#define SET_REMOTE_SHUTDOWN_OFF(dev) clear_bit(CONN_REMOTE_SHUTDOWN_BIT,\ + (void *) &(dev)->conn_state) +#define RX_FLOW_IS_ON(cf_sk) test_bit(RX_FLOW_ON_BIT,\ + (void *) &(cf_sk)->flow_state) +#define TX_FLOW_IS_ON(cf_sk) test_bit(TX_FLOW_ON_BIT,\ + (void *) &(cf_sk)->flow_state) + +#define SET_RX_FLOW_OFF(cf_sk) clear_bit(RX_FLOW_ON_BIT,\ + (void *) &(cf_sk)->flow_state) +#define SET_RX_FLOW_ON(cf_sk) set_bit(RX_FLOW_ON_BIT,\ + (void *) &(cf_sk)->flow_state) +#define SET_TX_FLOW_OFF(cf_sk) clear_bit(TX_FLOW_ON_BIT,\ + (void *) &(cf_sk)->flow_state) +#define SET_TX_FLOW_ON(cf_sk) set_bit(TX_FLOW_ON_BIT,\ + (void *) &(cf_sk)->flow_state) + +#define SKT_READ_FLAG 0x01 +#define SKT_WRITE_FLAG 0x02 +static struct dentry *debugfsdir; +#include + +#ifdef CONFIG_DEBUG_FS +struct debug_fs_counter { + atomic_t num_open; + atomic_t num_close; + atomic_t num_init; + atomic_t num_init_resp; + atomic_t num_init_fail_resp; + atomic_t num_deinit; + atomic_t num_deinit_resp; + atomic_t num_remote_shutdown_ind; + atomic_t num_tx_flow_off_ind; + atomic_t num_tx_flow_on_ind; + atomic_t num_rx_flow_off; + atomic_t num_rx_flow_on; + atomic_t skb_in_use; + atomic_t skb_alloc; + atomic_t skb_free; +}; +static struct debug_fs_counter cnt; +#define dbfs_atomic_inc(v) atomic_inc(v) +#define dbfs_atomic_dec(v) atomic_dec(v) +#else +#define dbfs_atomic_inc(v) +#define dbfs_atomic_dec(v) +#endif + +/* The AF_CAIF socket */ +struct caifsock { + /* NOTE: sk has to be the first member */ + struct sock sk; + struct cflayer layer; + char name[CAIF_LAYER_NAME_SZ]; + u32 conn_state; + u32 flow_state; + struct cfpktq *pktq; + int file_mode; + struct caif_connect_request conn_req; + int read_queue_len; + /* protect updates of read_queue_len */ + spinlock_t read_queue_len_lock; + struct dentry *debugfs_socket_dir; +}; + +static void drain_queue(struct caifsock *cf_sk); + +/* Packet Receive Callback function called from CAIF Stack */ +static int caif_sktrecv_cb(struct cflayer *layr, struct cfpkt *pkt) +{ + struct caifsock *cf_sk; + int read_queue_high; + cf_sk = container_of(layr, struct caifsock, layer); + + if (!STATE_IS_OPEN(cf_sk)) { + /*FIXME: This should be allowed finally!*/ + pr_debug("CAIF: %s(): called after close request\n", __func__); + cfpkt_destroy(pkt); + return 0; + } + /* NOTE: This function may be called in Tasklet context! */ + + /* The queue has its own lock */ + cfpkt_queue(cf_sk->pktq, pkt, 0); + + spin_lock(&cf_sk->read_queue_len_lock); + cf_sk->read_queue_len++; + + read_queue_high = (cf_sk->read_queue_len > CHNL_SKT_READ_QUEUE_HIGH); + spin_unlock(&cf_sk->read_queue_len_lock); + + if (RX_FLOW_IS_ON(cf_sk) && read_queue_high) { + dbfs_atomic_inc(&cnt.num_rx_flow_off); + SET_RX_FLOW_OFF(cf_sk); + + /* Send flow off (NOTE: must not sleep) */ + pr_debug("CAIF: %s():" + " sending flow OFF (queue len = %d)\n", + __func__, + cf_sk->read_queue_len); + caif_assert(cf_sk->layer.dn); + caif_assert(cf_sk->layer.dn->ctrlcmd); + + (void) cf_sk->layer.dn->modemcmd(cf_sk->layer.dn, + CAIF_MODEMCMD_FLOW_OFF_REQ); + } + + /* Signal reader that data is available. */ + + wake_up_interruptible(cf_sk->sk.sk_sleep); + + return 0; +} + +/* Packet Flow Control Callback function called from CAIF */ +static void caif_sktflowctrl_cb(struct cflayer *layr, + enum caif_ctrlcmd flow, + int phyid) +{ + struct caifsock *cf_sk; + + /* NOTE: This function may be called in Tasklet context! */ + pr_debug("CAIF: %s(): flowctrl func called: %s.\n", + __func__, + flow == CAIF_CTRLCMD_FLOW_ON_IND ? "ON" : + flow == CAIF_CTRLCMD_FLOW_OFF_IND ? "OFF" : + flow == CAIF_CTRLCMD_INIT_RSP ? "INIT_RSP" : + flow == CAIF_CTRLCMD_DEINIT_RSP ? "DEINIT_RSP" : + flow == CAIF_CTRLCMD_INIT_FAIL_RSP ? "INIT_FAIL_RSP" : + flow == + CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND ? "REMOTE_SHUTDOWN" : + "UKNOWN CTRL COMMAND"); + + if (layr == NULL) + return; + + cf_sk = container_of(layr, struct caifsock, layer); + + switch (flow) { + case CAIF_CTRLCMD_FLOW_ON_IND: + dbfs_atomic_inc(&cnt.num_tx_flow_on_ind); + /* Signal reader that data is available. */ + SET_TX_FLOW_ON(cf_sk); + wake_up_interruptible(cf_sk->sk.sk_sleep); + break; + + case CAIF_CTRLCMD_FLOW_OFF_IND: + dbfs_atomic_inc(&cnt.num_tx_flow_off_ind); + SET_TX_FLOW_OFF(cf_sk); + break; + + case CAIF_CTRLCMD_INIT_RSP: + dbfs_atomic_inc(&cnt.num_init_resp); + /* Signal reader that data is available. */ + caif_assert(STATE_IS_OPEN(cf_sk)); + SET_PENDING_OFF(cf_sk); + SET_TX_FLOW_ON(cf_sk); + wake_up_interruptible(cf_sk->sk.sk_sleep); + break; + + case CAIF_CTRLCMD_DEINIT_RSP: + dbfs_atomic_inc(&cnt.num_deinit_resp); + caif_assert(!STATE_IS_OPEN(cf_sk)); + SET_PENDING_OFF(cf_sk); + if (!STATE_IS_PENDING_DESTROY(cf_sk)) { + if (cf_sk->sk.sk_sleep != NULL) + wake_up_interruptible(cf_sk->sk.sk_sleep); + } + dbfs_atomic_inc(&cnt.num_deinit); + sock_put(&cf_sk->sk); + break; + + case CAIF_CTRLCMD_INIT_FAIL_RSP: + dbfs_atomic_inc(&cnt.num_init_fail_resp); + caif_assert(STATE_IS_OPEN(cf_sk)); + SET_STATE_CLOSED(cf_sk); + SET_PENDING_OFF(cf_sk); + SET_TX_FLOW_OFF(cf_sk); + wake_up_interruptible(cf_sk->sk.sk_sleep); + break; + + case CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND: + dbfs_atomic_inc(&cnt.num_remote_shutdown_ind); + SET_REMOTE_SHUTDOWN(cf_sk); + /* Use sk_shutdown to indicate remote shutdown indication */ + cf_sk->sk.sk_shutdown |= RCV_SHUTDOWN; + cf_sk->file_mode = 0; + wake_up_interruptible(cf_sk->sk.sk_sleep); + break; + + default: + pr_debug("CAIF: %s(): Unexpected flow command %d\n", + __func__, flow); + } +} + +static void skb_destructor(struct sk_buff *skb) +{ + dbfs_atomic_inc(&cnt.skb_free); + dbfs_atomic_dec(&cnt.skb_in_use); +} + + +static int caif_recvmsg(struct kiocb *iocb, struct socket *sock, + struct msghdr *m, size_t buf_len, int flags) + +{ + struct sock *sk = sock->sk; + struct caifsock *cf_sk = container_of(sk, struct caifsock, sk); + struct cfpkt *pkt = NULL; + size_t len; + int result; + struct sk_buff *skb; + ssize_t ret = -EIO; + int read_queue_low; + + if (cf_sk == NULL) { + pr_debug("CAIF: %s(): private_data not set!\n", + __func__); + ret = -EBADFD; + goto read_error; + } + + /* Don't do multiple iovec entries yet */ + if (m->msg_iovlen != 1) + return -EOPNOTSUPP; + + if (unlikely(!buf_len)) + return -EINVAL; + + lock_sock(&(cf_sk->sk)); + + caif_assert(cf_sk->pktq); + + if (!STATE_IS_OPEN(cf_sk)) { + /* Socket is closed or closing. */ + if (!STATE_IS_PENDING(cf_sk)) { + pr_debug("CAIF: %s(): socket is closed (by remote)\n", + __func__); + ret = -EPIPE; + } else { + pr_debug("CAIF: %s(): socket is closing..\n", __func__); + ret = -EBADF; + } + goto read_error; + } + /* Socket is open or opening. */ + if (STATE_IS_PENDING(cf_sk)) { + pr_debug("CAIF: %s(): socket is opening...\n", __func__); + + if (flags & MSG_DONTWAIT) { + /* We can't block. */ + pr_debug("CAIF: %s():state pending and MSG_DONTWAIT\n", + __func__); + ret = -EAGAIN; + goto read_error; + } + + /* + * Blocking mode; state is pending and we need to wait + * for its conclusion. + */ + release_sock(&cf_sk->sk); + + result = + wait_event_interruptible(*cf_sk->sk.sk_sleep, + !STATE_IS_PENDING(cf_sk)); + + lock_sock(&(cf_sk->sk)); + + if (result == -ERESTARTSYS) { + pr_debug("CAIF: %s(): wait_event_interruptible" + " woken by a signal (1)", __func__); + ret = -ERESTARTSYS; + goto read_error; + } + } + + if (STATE_IS_REMOTE_SHUTDOWN(cf_sk) || + !STATE_IS_OPEN(cf_sk) || + STATE_IS_PENDING(cf_sk)) { + + pr_debug("CAIF: %s(): socket closed\n", + __func__); + ret = -ESHUTDOWN; + goto read_error; + } + + /* + * Block if we don't have any received buffers. + * The queue has its own lock. + */ + while ((pkt = cfpkt_qpeek(cf_sk->pktq)) == NULL) { + + if (flags & MSG_DONTWAIT) { + pr_debug("CAIF: %s(): MSG_DONTWAIT\n", __func__); + ret = -EAGAIN; + goto read_error; + } + trace_printk("CAIF: %s() wait_event\n", __func__); + + /* Let writers in. */ + release_sock(&cf_sk->sk); + + /* Block reader until data arrives or socket is closed. */ + if (wait_event_interruptible(*cf_sk->sk.sk_sleep, + cfpkt_qpeek(cf_sk->pktq) + || STATE_IS_REMOTE_SHUTDOWN(cf_sk) + || !STATE_IS_OPEN(cf_sk)) == + -ERESTARTSYS) { + pr_debug("CAIF: %s():" + " wait_event_interruptible woken by " + "a signal, signal_pending(current) = %d\n", + __func__, + signal_pending(current)); + return -ERESTARTSYS; + } + + trace_printk("CAIF: %s() awake\n", __func__); + if (STATE_IS_REMOTE_SHUTDOWN(cf_sk)) { + pr_debug("CAIF: %s(): " + "received remote_shutdown indication\n", + __func__); + ret = -ESHUTDOWN; + goto read_error_no_unlock; + } + + /* I want to be alone on cf_sk (except status and queue). */ + lock_sock(&(cf_sk->sk)); + + if (!STATE_IS_OPEN(cf_sk)) { + /* Someone closed the link, report error. */ + pr_debug("CAIF: %s(): remote end shutdown!\n", + __func__); + ret = -EPIPE; + goto read_error; + } + } + + /* The queue has its own lock. */ + len = cfpkt_getlen(pkt); + + /* Check max length that can be copied. */ + if (len <= buf_len) + pkt = cfpkt_dequeue(cf_sk->pktq); + else { + pr_debug("CAIF: %s(): user buffer too small (%ld,%ld)\n", + __func__, (long) len, (long) buf_len); + if (sock->type == SOCK_SEQPACKET) { + ret = -EMSGSIZE; + goto read_error; + } + len = buf_len; + } + + + spin_lock(&cf_sk->read_queue_len_lock); + cf_sk->read_queue_len--; + read_queue_low = (cf_sk->read_queue_len < CHNL_SKT_READ_QUEUE_LOW); + spin_unlock(&cf_sk->read_queue_len_lock); + + if (!RX_FLOW_IS_ON(cf_sk) && read_queue_low) { + dbfs_atomic_inc(&cnt.num_rx_flow_on); + SET_RX_FLOW_ON(cf_sk); + + /* Send flow on. */ + pr_debug("CAIF: %s(): sending flow ON (queue len = %d)\n", + __func__, cf_sk->read_queue_len); + caif_assert(cf_sk->layer.dn); + caif_assert(cf_sk->layer.dn->ctrlcmd); + (void) cf_sk->layer.dn->modemcmd(cf_sk->layer.dn, + CAIF_MODEMCMD_FLOW_ON_REQ); + + caif_assert(cf_sk->read_queue_len >= 0); + } + + skb = cfpkt_tonative(pkt); + result = skb_copy_datagram_iovec(skb, 0, m->msg_iov, len); + skb_pull(skb, len); + + if (result) { + pr_debug("CAIF: %s(): copy to_iovec failed\n", __func__); + cfpkt_destroy(pkt); + ret = -EFAULT; + goto read_error; + } + + /* Free packet and remove from queue */ + if (skb->len == 0) + skb_free_datagram(sk, skb); + + /* Let the others in. */ + release_sock(&cf_sk->sk); + return len; + +read_error: + release_sock(&cf_sk->sk); +read_error_no_unlock: + return ret; +} + +/* Send a signal as a consequence of sendmsg, sendto or caif_sendmsg. */ +static int caif_sendmsg(struct kiocb *kiocb, struct socket *sock, + struct msghdr *msg, size_t len) +{ + + struct sock *sk = sock->sk; + struct caifsock *cf_sk = container_of(sk, struct caifsock, sk); + size_t payload_size = msg->msg_iov->iov_len; + struct cfpkt *pkt = NULL; + struct caif_payload_info info; + unsigned char *txbuf; + ssize_t ret = -EIO; + int result; + struct sk_buff *skb; + caif_assert(msg->msg_iovlen == 1); + + if (cf_sk == NULL) { + pr_debug("CAIF: %s(): private_data not set!\n", + __func__); + ret = -EBADFD; + goto write_error_no_unlock; + } + + if (unlikely(msg->msg_iov->iov_base == NULL)) { + pr_warning("CAIF: %s(): Buffer is NULL.\n", __func__); + ret = -EINVAL; + goto write_error_no_unlock; + } + + if (payload_size > CAIF_MAX_PAYLOAD_SIZE) { + pr_debug("CAIF: %s(): buffer too long\n", __func__); + if (sock->type == SOCK_SEQPACKET) { + ret = -EINVAL; + goto write_error_no_unlock; + } + payload_size = CAIF_MAX_PAYLOAD_SIZE; + } + + /* I want to be alone on cf_sk (except status and queue) */ + lock_sock(&(cf_sk->sk)); + + caif_assert(cf_sk->pktq); + + if (!STATE_IS_OPEN(cf_sk)) { + /* Socket is closed or closing */ + if (!STATE_IS_PENDING(cf_sk)) { + pr_debug("CAIF: %s(): socket is closed (by remote)\n", + __func__); + ret = -EPIPE; + } else { + pr_debug("CAIF: %s(): socket is closing...\n", + __func__); + ret = -EBADF; + } + goto write_error; + } + + /* Socket is open or opening */ + if (STATE_IS_PENDING(cf_sk)) { + pr_debug("CAIF: %s(): socket is opening...\n", __func__); + + if (msg->msg_flags & MSG_DONTWAIT) { + /* We can't block */ + trace_printk("CAIF: %s():state pending:" + "state=MSG_DONTWAIT\n", __func__); + ret = -EAGAIN; + goto write_error; + } + /* Let readers in */ + release_sock(&cf_sk->sk); + + /* + * Blocking mode; state is pending and we need to wait + * for its conclusion. + */ + result = + wait_event_interruptible(*cf_sk->sk.sk_sleep, + !STATE_IS_PENDING(cf_sk)); + /* I want to be alone on cf_sk (except status and queue) */ + lock_sock(&(cf_sk->sk)); + + if (result == -ERESTARTSYS) { + pr_debug("CAIF: %s(): wait_event_interruptible" + " woken by a signal (1)", __func__); + ret = -ERESTARTSYS; + goto write_error; + } + } + if (STATE_IS_REMOTE_SHUTDOWN(cf_sk) || + !STATE_IS_OPEN(cf_sk) || + STATE_IS_PENDING(cf_sk)) { + + pr_debug("CAIF: %s(): socket closed\n", + __func__); + ret = -ESHUTDOWN; + goto write_error; + } + + if (!TX_FLOW_IS_ON(cf_sk)) { + + /* Flow is off. Check non-block flag */ + if (msg->msg_flags & MSG_DONTWAIT) { + trace_printk("CAIF: %s(): MSG_DONTWAIT and tx flow off", + __func__); + ret = -EAGAIN; + goto write_error; + } + + /* release lock before waiting */ + release_sock(&cf_sk->sk); + + /* Wait until flow is on or socket is closed */ + if (wait_event_interruptible(*cf_sk->sk.sk_sleep, + TX_FLOW_IS_ON(cf_sk) + || !STATE_IS_OPEN(cf_sk) + || STATE_IS_REMOTE_SHUTDOWN(cf_sk) + ) == -ERESTARTSYS) { + pr_debug("CAIF: %s():" + " wait_event_interruptible woken by a signal", + __func__); + ret = -ERESTARTSYS; + goto write_error_no_unlock; + } + + /* I want to be alone on cf_sk (except status and queue) */ + lock_sock(&(cf_sk->sk)); + + if (!STATE_IS_OPEN(cf_sk)) { + /* someone closed the link, report error */ + pr_debug("CAIF: %s(): remote end shutdown!\n", + __func__); + ret = -EPIPE; + goto write_error; + } + + if (STATE_IS_REMOTE_SHUTDOWN(cf_sk)) { + pr_debug("CAIF: %s(): " + "received remote_shutdown indication\n", + __func__); + ret = -ESHUTDOWN; + goto write_error; + } + } + + pkt = cfpkt_create(payload_size); + skb = (struct sk_buff *)pkt; + skb->destructor = skb_destructor; + skb->sk = sk; + dbfs_atomic_inc(&cnt.skb_alloc); + dbfs_atomic_inc(&cnt.skb_in_use); + if (cfpkt_raw_append(pkt, (void **) &txbuf, payload_size) < 0) { + pr_debug("CAIF: %s(): cfpkt_raw_append failed\n", __func__); + cfpkt_destroy(pkt); + ret = -EINVAL; + goto write_error; + } + + /* Copy data into buffer. */ + if (copy_from_user(txbuf, msg->msg_iov->iov_base, payload_size)) { + pr_debug("CAIF: %s(): copy_from_user returned non zero.\n", + __func__); + cfpkt_destroy(pkt); + ret = -EINVAL; + goto write_error; + } + memset(&info, 0, sizeof(info)); + + /* Send the packet down the stack. */ + caif_assert(cf_sk->layer.dn); + caif_assert(cf_sk->layer.dn->transmit); + + do { + ret = cf_sk->layer.dn->transmit(cf_sk->layer.dn, pkt); + + if (likely((ret >= 0) || (ret != -EAGAIN))) + break; + + /* EAGAIN - retry */ + if (msg->msg_flags & MSG_DONTWAIT) { + pr_debug("CAIF: %s(): NONBLOCK and transmit failed," + " error = %ld\n", __func__, (long) ret); + ret = -EAGAIN; + goto write_error; + } + + /* Let readers in */ + release_sock(&cf_sk->sk); + + /* Wait until flow is on or socket is closed */ + if (wait_event_interruptible(*cf_sk->sk.sk_sleep, + TX_FLOW_IS_ON(cf_sk) + || !STATE_IS_OPEN(cf_sk) + || STATE_IS_REMOTE_SHUTDOWN(cf_sk) + ) == -ERESTARTSYS) { + pr_debug("CAIF: %s(): wait_event_interruptible" + " woken by a signal", __func__); + ret = -ERESTARTSYS; + goto write_error_no_unlock; + } + + /* I want to be alone on cf_sk (except status and queue) */ + lock_sock(&(cf_sk->sk)); + + } while (ret == -EAGAIN); + + if (ret < 0) { + cfpkt_destroy(pkt); + pr_debug("CAIF: %s(): transmit failed, error = %ld\n", + __func__, (long) ret); + + goto write_error; + } + + release_sock(&cf_sk->sk); + return payload_size; + +write_error: + release_sock(&cf_sk->sk); +write_error_no_unlock: + return ret; +} + +static unsigned int caif_poll(struct file *file, struct socket *sock, + poll_table *wait) +{ + struct sock *sk = sock->sk; + struct caifsock *cf_sk = container_of(sk, struct caifsock, sk); + u32 mask = 0; + poll_wait(file, sk->sk_sleep, wait); + lock_sock(&(cf_sk->sk)); + if (!STATE_IS_OPEN(cf_sk)) { + if (!STATE_IS_PENDING(cf_sk)) + mask |= POLLHUP; + } else { + if (cfpkt_qpeek(cf_sk->pktq) != NULL) + mask |= (POLLIN | POLLRDNORM); + if (TX_FLOW_IS_ON(cf_sk)) + mask |= (POLLOUT | POLLWRNORM); + } + release_sock(&cf_sk->sk); + trace_printk("CAIF: %s(): poll mask=0x%04x\n", + __func__, mask); + return mask; +} + +static void drain_queue(struct caifsock *cf_sk) +{ + struct cfpkt *pkt = NULL; + + /* Empty the queue */ + do { + /* The queue has its own lock */ + if (!cf_sk->pktq) + break; + + pkt = cfpkt_dequeue(cf_sk->pktq); + if (!pkt) + break; + pr_debug("CAIF: %s(): freeing packet from read queue\n", + __func__); + cfpkt_destroy(pkt); + + } while (1); + + cf_sk->read_queue_len = 0; +} + +static int setsockopt(struct socket *sock, + int lvl, int opt, char __user *ov, unsigned int ol) +{ + struct sock *sk = sock->sk; + struct caifsock *cf_sk = container_of(sk, struct caifsock, sk); + int prio, linksel; + struct ifreq ifreq; + + if (STATE_IS_OPEN(cf_sk)) { + pr_debug("CAIF: %s(): setsockopt " + "cannot be done on a connected socket\n", + __func__); + return -ENOPROTOOPT; + } + switch (opt) { + case CAIFSO_LINK_SELECT: + if (ol < sizeof(int)) { + pr_debug("CAIF: %s(): setsockopt" + " CAIFSO_CHANNEL_CONFIG bad size\n", __func__); + return -EINVAL; + } + if (lvl != SOL_CAIF) + goto bad_sol; + if (copy_from_user(&linksel, ov, sizeof(int))) + return -EINVAL; + lock_sock(&(cf_sk->sk)); + cf_sk->conn_req.link_selector = linksel; + release_sock(&cf_sk->sk); + return 0; + + case SO_PRIORITY: + if (lvl != SOL_SOCKET) + goto bad_sol; + if (ol < sizeof(int)) { + pr_debug("CAIF: %s(): setsockopt" + " SO_PRIORITY bad size\n", __func__); + return -EINVAL; + } + if (copy_from_user(&prio, ov, sizeof(int))) + return -EINVAL; + lock_sock(&(cf_sk->sk)); + cf_sk->conn_req.priority = prio; + pr_debug("CAIF: %s(): Setting sockopt priority=%d\n", __func__, + cf_sk->conn_req.priority); + release_sock(&cf_sk->sk); + return 0; + + case SO_BINDTODEVICE: + if (lvl != SOL_SOCKET) + goto bad_sol; + if (ol < sizeof(struct ifreq)) { + pr_debug("CAIF: %s(): setsockopt" + " SO_PRIORITY bad size\n", __func__); + return -EINVAL; + } + if (copy_from_user(&ifreq, ov, sizeof(ifreq))) + return -EFAULT; + lock_sock(&(cf_sk->sk)); + strncpy(cf_sk->conn_req.link_name, ifreq.ifr_name, + sizeof(cf_sk->conn_req.link_name)); + cf_sk->conn_req.link_name + [sizeof(cf_sk->conn_req.link_name)-1] = 0; + release_sock(&cf_sk->sk); + return 0; + + case CAIFSO_REQ_PARAM: + if (lvl != SOL_CAIF) + goto bad_sol; + if (cf_sk->sk.sk_protocol != CAIFPROTO_UTIL) + return -ENOPROTOOPT; + if (ol > sizeof(cf_sk->conn_req.param.data)) + goto req_param_bad_size; + + lock_sock(&(cf_sk->sk)); + cf_sk->conn_req.param.size = ol; + if (copy_from_user(&cf_sk->conn_req.param.data, ov, ol)) { + release_sock(&cf_sk->sk); +req_param_bad_size: + pr_debug("CAIF: %s(): setsockopt" + " CAIFSO_CHANNEL_CONFIG bad size\n", __func__); + return -EINVAL; + } + + release_sock(&cf_sk->sk); + return 0; + + default: + pr_debug("CAIF: %s(): unhandled option %d\n", __func__, opt); + return -EINVAL; + } + + return 0; +bad_sol: + pr_debug("CAIF: %s(): setsockopt bad level\n", __func__); + return -ENOPROTOOPT; + +} + +static int caif_connect(struct socket *sock, struct sockaddr *uservaddr, + int sockaddr_len, int flags) +{ + struct caifsock *cf_sk = NULL; + int result = -1; + int mode = 0; + int ret = -EIO; + struct sock *sk = sock->sk; + BUG_ON(sk == NULL); + + cf_sk = container_of(sk, struct caifsock, sk); + + trace_printk("CAIF: %s(): cf_sk=%p OPEN=%d, TX_FLOW=%d, RX_FLOW=%d\n", + __func__, cf_sk, + STATE_IS_OPEN(cf_sk), + TX_FLOW_IS_ON(cf_sk), RX_FLOW_IS_ON(cf_sk)); + + + if (sock->type == SOCK_SEQPACKET || sock->type == SOCK_STREAM) + sock->state = SS_CONNECTING; + else + goto out; + + /* I want to be alone on cf_sk (except status and queue) */ + lock_sock(&(cf_sk->sk)); + + if (sockaddr_len != sizeof(struct sockaddr_caif)) { + pr_debug("CAIF: %s(): Bad address len (%ld,%lu)\n", + __func__, (long) sockaddr_len, + (long unsigned) sizeof(struct sockaddr_caif)); + ret = -EINVAL; + goto open_error; + } + + if (uservaddr->sa_family != AF_CAIF) { + pr_debug("CAIF: %s(): Bad address family (%d)\n", + __func__, uservaddr->sa_family); + ret = -EAFNOSUPPORT; + goto open_error; + } + + memcpy(&cf_sk->conn_req.sockaddr, uservaddr, + sizeof(struct sockaddr_caif)); + + dbfs_atomic_inc(&cnt.num_open); + mode = SKT_READ_FLAG | SKT_WRITE_FLAG; + + /* If socket is not open, make sure socket is in fully closed state */ + if (!STATE_IS_OPEN(cf_sk)) { + /* Has link close response been received (if we ever sent it)?*/ + if (STATE_IS_PENDING(cf_sk)) { + /* + * Still waiting for close response from remote. + * If opened non-blocking, report "would block" + */ + if (flags & O_NONBLOCK) { + pr_debug("CAIF: %s(): O_NONBLOCK" + " && close pending\n", __func__); + ret = -EAGAIN; + goto open_error; + } + + pr_debug("CAIF: %s(): Wait for close response" + " from remote...\n", __func__); + + release_sock(&cf_sk->sk); + + /* + * Blocking mode; close is pending and we need to wait + * for its conclusion. + */ + result = + wait_event_interruptible(*cf_sk->sk.sk_sleep, + !STATE_IS_PENDING(cf_sk)); + + lock_sock(&(cf_sk->sk)); + if (result == -ERESTARTSYS) { + pr_debug("CAIF: %s(): wait_event_interruptible" + "woken by a signal (1)", __func__); + ret = -ERESTARTSYS; + goto open_error; + } + } + } + + /* socket is now either closed, pending open or open */ + if (STATE_IS_OPEN(cf_sk) && !STATE_IS_PENDING(cf_sk)) { + /* Open */ + pr_debug("CAIF: %s(): Socket is already opened (cf_sk=%p)" + " check access f_flags = 0x%x file_mode = 0x%x\n", + __func__, cf_sk, mode, cf_sk->file_mode); + + } else { + /* We are closed or pending open. + * If closed: send link setup + * If pending open: link setup already sent (we could have been + * interrupted by a signal last time) + */ + if (!STATE_IS_OPEN(cf_sk)) { + /* First opening of file; connect lower layers: */ + /* Drain queue (very unlikely) */ + drain_queue(cf_sk); + + cf_sk->layer.receive = caif_sktrecv_cb; + SET_STATE_OPEN(cf_sk); + SET_PENDING_ON(cf_sk); + + /* Register this channel. */ + result = + caif_connect_client(&cf_sk->conn_req, + &cf_sk->layer); + if (result < 0) { + pr_debug("CAIF: %s(): can't register channel\n", + __func__); + ret = -EIO; + SET_STATE_CLOSED(cf_sk); + SET_PENDING_OFF(cf_sk); + goto open_error; + } + dbfs_atomic_inc(&cnt.num_init); + } + + /* If opened non-blocking, report "success". + */ + if (flags & O_NONBLOCK) { + pr_debug("CAIF: %s(): O_NONBLOCK success\n", + __func__); + ret = -EINPROGRESS; + cf_sk->sk.sk_err = -EINPROGRESS; + goto open_error; + } + + trace_printk("CAIF: %s(): Wait for connect response\n", + __func__); + + /* release lock before waiting */ + release_sock(&cf_sk->sk); + + result = + wait_event_interruptible(*cf_sk->sk.sk_sleep, + !STATE_IS_PENDING(cf_sk)); + + lock_sock(&(cf_sk->sk)); + + if (result == -ERESTARTSYS) { + pr_debug("CAIF: %s(): wait_event_interruptible" + "woken by a signal (2)", __func__); + ret = -ERESTARTSYS; + goto open_error; + } + + if (!STATE_IS_OPEN(cf_sk)) { + /* Lower layers said "no" */ + pr_debug("CAIF: %s(): Closed received\n", __func__); + ret = -EPIPE; + goto open_error; + } + + trace_printk("CAIF: %s(): Connect received\n", __func__); + } + /* Open is ok */ + cf_sk->file_mode |= mode; + + trace_printk("CAIF: %s(): Connected - file mode = %x\n", + __func__, cf_sk->file_mode); + + release_sock(&cf_sk->sk); + return 0; +open_error: + sock->state = SS_UNCONNECTED; + release_sock(&cf_sk->sk); +out: + return ret; +} + +static int caif_shutdown(struct socket *sock, int how) +{ + struct caifsock *cf_sk = NULL; + int result = 0; + int tx_flow_state_was_on; + struct sock *sk = sock->sk; + + trace_printk("CAIF: %s(): enter\n", __func__); + pr_debug("f_flags=%x\n", sock->file->f_flags); + + if (how != SHUT_RDWR) + return -EOPNOTSUPP; + + cf_sk = container_of(sk, struct caifsock, sk); + if (cf_sk == NULL) { + pr_debug("CAIF: %s(): COULD NOT FIND SOCKET\n", __func__); + return -EBADF; + } + + /* I want to be alone on cf_sk (except status queue) */ + lock_sock(&(cf_sk->sk)); + sock_hold(&cf_sk->sk); + + /* IS_CLOSED have double meaning: + * 1) Spontanous Remote Shutdown Request. + * 2) Ack on a channel teardown(disconnect) + * Must clear bit in case we previously received + * remote shudown request. + */ + if (STATE_IS_OPEN(cf_sk) && !STATE_IS_PENDING(cf_sk)) { + SET_STATE_CLOSED(cf_sk); + SET_PENDING_ON(cf_sk); + tx_flow_state_was_on = TX_FLOW_IS_ON(cf_sk); + SET_TX_FLOW_OFF(cf_sk); + + /* Hold the socket until DEINIT_RSP is received */ + sock_hold(&cf_sk->sk); + result = caif_disconnect_client(&cf_sk->layer); + + if (result < 0) { + pr_debug("CAIF: %s(): " + "caif_disconnect_client() failed\n", + __func__); + SET_STATE_CLOSED(cf_sk); + SET_PENDING_OFF(cf_sk); + SET_TX_FLOW_OFF(cf_sk); + release_sock(&cf_sk->sk); + sock_put(&cf_sk->sk); + return -EIO; + } + + } + if (STATE_IS_REMOTE_SHUTDOWN(cf_sk)) { + SET_PENDING_OFF(cf_sk); + SET_REMOTE_SHUTDOWN_OFF(cf_sk); + } + + /* + * Socket is no longer in state pending close, + * and we can release the reference. + */ + + dbfs_atomic_inc(&cnt.num_close); + drain_queue(cf_sk); + SET_RX_FLOW_ON(cf_sk); + cf_sk->file_mode = 0; + sock_put(&cf_sk->sk); + release_sock(&cf_sk->sk); + if (!result && (sock->file->f_flags & O_NONBLOCK)) { + pr_debug("nonblocking shutdown returing -EAGAIN\n"); + return -EAGAIN; + } else + return result; +} + +static ssize_t caif_sock_no_sendpage(struct socket *sock, + struct page *page, + int offset, size_t size, int flags) +{ + return -EOPNOTSUPP; +} + +/* This function is called as part of close. */ +static int caif_release(struct socket *sock) +{ + struct sock *sk = sock->sk; + struct caifsock *cf_sk = NULL; + int res; + caif_assert(sk != NULL); + cf_sk = container_of(sk, struct caifsock, sk); + + if (cf_sk->debugfs_socket_dir != NULL) + debugfs_remove_recursive(cf_sk->debugfs_socket_dir); + + res = caif_shutdown(sock, SHUT_RDWR); + if (res && res != -EINPROGRESS) + return res; + + /* + * FIXME: Shutdown should probably be possible to do async + * without flushing queues, allowing reception of frames while + * waiting for DEINIT_IND. + * Release should always block, to allow secure decoupling of + * CAIF stack. + */ + if (!(sock->file->f_flags & O_NONBLOCK)) { + res = wait_event_interruptible(*cf_sk->sk.sk_sleep, + !STATE_IS_PENDING(cf_sk)); + + if (res == -ERESTARTSYS) { + pr_debug("CAIF: %s(): wait_event_interruptible" + "woken by a signal (1)", __func__); + } + } + lock_sock(&(cf_sk->sk)); + + sock->sk = NULL; + + /* Detach the socket from its process context by making it orphan. */ + sock_orphan(sk); + + /* + * Setting SHUTDOWN_MASK means that both send and receive are shutdown + * for the socket. + */ + sk->sk_shutdown = SHUTDOWN_MASK; + + /* + * Set the socket state to closed, the TCP_CLOSE macro is used when + * closing any socket. + */ + + /* Flush out this sockets receive queue. */ + drain_queue(cf_sk); + + /* Finally release the socket. */ + SET_STATE_PENDING_DESTROY(cf_sk); + + release_sock(&cf_sk->sk); + + sock_put(sk); + + /* + * The rest of the cleanup will be handled from the + * caif_sock_destructor + */ + return res; +} + +static const struct proto_ops caif_ops = { + .family = PF_CAIF, + .owner = THIS_MODULE, + .release = caif_release, + .bind = sock_no_bind, + .connect = caif_connect, + .socketpair = sock_no_socketpair, + .accept = sock_no_accept, + .getname = sock_no_getname, + .poll = caif_poll, + .ioctl = sock_no_ioctl, + .listen = sock_no_listen, + .shutdown = caif_shutdown, + .setsockopt = setsockopt, + .getsockopt = sock_no_getsockopt, + .sendmsg = caif_sendmsg, + .recvmsg = caif_recvmsg, + .mmap = sock_no_mmap, + .sendpage = caif_sock_no_sendpage, +}; + +/* This function is called when a socket is finally destroyed. */ +static void caif_sock_destructor(struct sock *sk) +{ + struct caifsock *cf_sk = NULL; + cf_sk = container_of(sk, struct caifsock, sk); + /* Error checks. */ + caif_assert(!atomic_read(&sk->sk_wmem_alloc)); + caif_assert(sk_unhashed(sk)); + caif_assert(!sk->sk_socket); + if (!sock_flag(sk, SOCK_DEAD)) { + pr_debug("CAIF: %s(): 0x%p", __func__, sk); + return; + } + + if (STATE_IS_OPEN(cf_sk)) { + pr_debug("CAIF: %s(): socket is opened (cf_sk=%p)" + " file_mode = 0x%x\n", __func__, + cf_sk, cf_sk->file_mode); + return; + } + drain_queue(cf_sk); + kfree(cf_sk->pktq); + + trace_printk("CAIF: %s(): caif_sock_destructor: Removing socket %s\n", + __func__, cf_sk->name); + atomic_dec(&caif_nr_socks); +} + +static int caif_create(struct net *net, struct socket *sock, int protocol, + int kern) +{ + struct sock *sk = NULL; + struct caifsock *cf_sk = NULL; + int result = 0; + static struct proto prot = {.name = "PF_CAIF", + .owner = THIS_MODULE, + .obj_size = sizeof(struct caifsock), + }; + + /* + * The sock->type specifies the socket type to use. + * in SEQPACKET mode packet boundaries are enforced. + */ + if (sock->type != SOCK_SEQPACKET && sock->type != SOCK_STREAM) + return -ESOCKTNOSUPPORT; + + if (net != &init_net) + return -EAFNOSUPPORT; + + if (protocol < 0 || protocol >= CAIFPROTO_MAX) + return -EPROTONOSUPPORT; + /* + * Set the socket state to unconnected. The socket state is really + * not used at all in the net/core or socket.c but the + * initialization makes sure that sock->state is not uninitialized. + */ + sock->state = SS_UNCONNECTED; + + sk = sk_alloc(net, PF_CAIF, GFP_KERNEL, &prot); + if (!sk) + return -ENOMEM; + + cf_sk = container_of(sk, struct caifsock, sk); + + /* Store the protocol */ + sk->sk_protocol = (unsigned char) protocol; + + spin_lock_init(&cf_sk->read_queue_len_lock); + + /* Fill in some information concerning the misc socket. */ + snprintf(cf_sk->name, sizeof(cf_sk->name), "cf_sk%d", + atomic_read(&caif_nr_socks)); + + /* + * Lock in order to try to stop someone from opening the socket + * too early. + */ + lock_sock(&(cf_sk->sk)); + + /* Initialize the nozero default sock structure data. */ + sock_init_data(sock, sk); + sock->ops = &caif_ops; + sk->sk_destruct = caif_sock_destructor; + sk->sk_sndbuf = caif_sockbuf_size; + sk->sk_rcvbuf = caif_sockbuf_size; + + cf_sk->pktq = cfpktq_create(); + + if (!cf_sk->pktq) { + pr_err("CAIF: %s(): queue create failed.\n", __func__); + result = -ENOMEM; + release_sock(&cf_sk->sk); + goto err_failed; + } + cf_sk->layer.ctrlcmd = caif_sktflowctrl_cb; + SET_STATE_CLOSED(cf_sk); + SET_PENDING_OFF(cf_sk); + SET_TX_FLOW_OFF(cf_sk); + SET_RX_FLOW_ON(cf_sk); + + /* Set default options on configuration */ + cf_sk->conn_req.priority = CAIF_PRIO_NORMAL; + cf_sk->conn_req.link_selector = CAIF_LINK_HIGH_BANDW; + cf_sk->conn_req.protocol = protocol; + /* Increase the number of sockets created. */ + atomic_inc(&caif_nr_socks); + if (!IS_ERR(debugfsdir)) { + cf_sk->debugfs_socket_dir = + debugfs_create_dir(cf_sk->name, debugfsdir); + debugfs_create_u32("conn_state", S_IRUSR | S_IWUSR, + cf_sk->debugfs_socket_dir, &cf_sk->conn_state); + debugfs_create_u32("flow_state", S_IRUSR | S_IWUSR, + cf_sk->debugfs_socket_dir, &cf_sk->flow_state); + debugfs_create_u32("read_queue_len", S_IRUSR | S_IWUSR, + cf_sk->debugfs_socket_dir, + (u32 *) &cf_sk->read_queue_len); + debugfs_create_u32("identity", S_IRUSR | S_IWUSR, + cf_sk->debugfs_socket_dir, + (u32 *) &cf_sk->layer.id); + } + release_sock(&cf_sk->sk); + return 0; +err_failed: + sk_free(sk); + return result; +} + +static struct net_proto_family caif_family_ops = { + .family = PF_CAIF, + .create = caif_create, + .owner = THIS_MODULE, +}; + +static int af_caif_init(void) +{ + int err; + err = sock_register(&caif_family_ops); + + if (!err) + return err; + + return 0; +} + +static int __init caif_sktinit_module(void) +{ + int stat; +#ifdef CONFIG_DEBUG_FS + debugfsdir = debugfs_create_dir("chnl_skt", NULL); + if (!IS_ERR(debugfsdir)) { + debugfs_create_u32("skb_inuse", S_IRUSR | S_IWUSR, + debugfsdir, + (u32 *) &cnt.skb_in_use); + debugfs_create_u32("skb_alloc", S_IRUSR | S_IWUSR, + debugfsdir, + (u32 *) &cnt.skb_alloc); + debugfs_create_u32("skb_free", S_IRUSR | S_IWUSR, + debugfsdir, + (u32 *) &cnt.skb_free); + debugfs_create_u32("num_sockets", S_IRUSR | S_IWUSR, + debugfsdir, + (u32 *) &caif_nr_socks); + debugfs_create_u32("num_open", S_IRUSR | S_IWUSR, + debugfsdir, + (u32 *) &cnt.num_open); + debugfs_create_u32("num_close", S_IRUSR | S_IWUSR, + debugfsdir, + (u32 *) &cnt.num_close); + debugfs_create_u32("num_init", S_IRUSR | S_IWUSR, + debugfsdir, + (u32 *) &cnt.num_init); + debugfs_create_u32("num_init_resp", S_IRUSR | S_IWUSR, + debugfsdir, + (u32 *) &cnt.num_init_resp); + debugfs_create_u32("num_init_fail_resp", S_IRUSR | S_IWUSR, + debugfsdir, + (u32 *) &cnt.num_init_fail_resp); + debugfs_create_u32("num_deinit", S_IRUSR | S_IWUSR, + debugfsdir, + (u32 *) &cnt.num_deinit); + debugfs_create_u32("num_deinit_resp", S_IRUSR | S_IWUSR, + debugfsdir, + (u32 *) &cnt.num_deinit_resp); + debugfs_create_u32("num_remote_shutdown_ind", + S_IRUSR | S_IWUSR, debugfsdir, + (u32 *) &cnt.num_remote_shutdown_ind); + debugfs_create_u32("num_tx_flow_off_ind", S_IRUSR | S_IWUSR, + debugfsdir, + (u32 *) &cnt.num_tx_flow_off_ind); + debugfs_create_u32("num_tx_flow_on_ind", S_IRUSR | S_IWUSR, + debugfsdir, + (u32 *) &cnt.num_tx_flow_on_ind); + debugfs_create_u32("num_rx_flow_off", S_IRUSR | S_IWUSR, + debugfsdir, + (u32 *) &cnt.num_rx_flow_off); + debugfs_create_u32("num_rx_flow_on", S_IRUSR | S_IWUSR, + debugfsdir, + (u32 *) &cnt.num_rx_flow_on); + } +#endif + stat = af_caif_init(); + if (stat) { + pr_err("CAIF: %s(): Failed to initialize CAIF socket layer.", + __func__); + return stat; + } + return 0; +} + +static void __exit caif_sktexit_module(void) +{ + sock_unregister(PF_CAIF); + if (debugfsdir != NULL) + debugfs_remove_recursive(debugfsdir); +} + +module_init(caif_sktinit_module); +module_exit(caif_sktexit_module);