diff options
Diffstat (limited to 'drivers/rapidio/rio_cm.c')
| -rw-r--r-- | drivers/rapidio/rio_cm.c | 2366 |
1 files changed, 2366 insertions, 0 deletions
diff --git a/drivers/rapidio/rio_cm.c b/drivers/rapidio/rio_cm.c new file mode 100644 index 000000000000..cecc15a880de --- /dev/null +++ b/drivers/rapidio/rio_cm.c @@ -0,0 +1,2366 @@ +/* + * rio_cm - RapidIO Channelized Messaging Driver + * + * Copyright 2013-2016 Integrated Device Technology, Inc. + * Copyright (c) 2015, Prodrive Technologies + * Copyright (c) 2015, RapidIO Trade Association + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. + * + * THIS PROGRAM IS DISTRIBUTED IN THE HOPE THAT IT WILL BE USEFUL, + * BUT WITHOUT ANY WARRANTY; WITHOUT EVEN THE IMPLIED WARRANTY OF + * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. SEE THE + * GNU GENERAL PUBLIC LICENSE FOR MORE DETAILS. + */ + +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/dma-mapping.h> +#include <linux/delay.h> +#include <linux/sched.h> +#include <linux/rio.h> +#include <linux/rio_drv.h> +#include <linux/slab.h> +#include <linux/idr.h> +#include <linux/interrupt.h> +#include <linux/cdev.h> +#include <linux/fs.h> +#include <linux/poll.h> +#include <linux/reboot.h> +#include <linux/bitops.h> +#include <linux/printk.h> +#include <linux/rio_cm_cdev.h> + +#define DRV_NAME "rio_cm" +#define DRV_VERSION "1.0.0" +#define DRV_AUTHOR "Alexandre Bounine <alexandre.bounine@idt.com>" +#define DRV_DESC "RapidIO Channelized Messaging Driver" +#define DEV_NAME "rio_cm" + +/* Debug output filtering masks */ +enum { + DBG_NONE = 0, + DBG_INIT = BIT(0), /* driver init */ + DBG_EXIT = BIT(1), /* driver exit */ + DBG_MPORT = BIT(2), /* mport add/remove */ + DBG_RDEV = BIT(3), /* RapidIO device add/remove */ + DBG_CHOP = BIT(4), /* channel operations */ + DBG_WAIT = BIT(5), /* waiting for events */ + DBG_TX = BIT(6), /* message TX */ + DBG_TX_EVENT = BIT(7), /* message TX event */ + DBG_RX_DATA = BIT(8), /* inbound data messages */ + DBG_RX_CMD = BIT(9), /* inbound REQ/ACK/NACK messages */ + DBG_ALL = ~0, +}; + +#ifdef DEBUG +#define riocm_debug(level, fmt, arg...) \ + do { \ + if (DBG_##level & dbg_level) \ + pr_debug(DRV_NAME ": %s " fmt "\n", \ + __func__, ##arg); \ + } while (0) +#else +#define riocm_debug(level, fmt, arg...) \ + no_printk(KERN_DEBUG pr_fmt(DRV_NAME fmt "\n"), ##arg) +#endif + +#define riocm_warn(fmt, arg...) \ + pr_warn(DRV_NAME ": %s WARNING " fmt "\n", __func__, ##arg) + +#define riocm_error(fmt, arg...) \ + pr_err(DRV_NAME ": %s ERROR " fmt "\n", __func__, ##arg) + + +static int cmbox = 1; +module_param(cmbox, int, S_IRUGO); +MODULE_PARM_DESC(cmbox, "RapidIO Mailbox number (default 1)"); + +static int chstart = 256; +module_param(chstart, int, S_IRUGO); +MODULE_PARM_DESC(chstart, + "Start channel number for dynamic allocation (default 256)"); + +#ifdef DEBUG +static u32 dbg_level = DBG_NONE; +module_param(dbg_level, uint, S_IWUSR | S_IRUGO); +MODULE_PARM_DESC(dbg_level, "Debugging output level (default 0 = none)"); +#endif + +MODULE_AUTHOR(DRV_AUTHOR); +MODULE_DESCRIPTION(DRV_DESC); +MODULE_LICENSE("GPL"); +MODULE_VERSION(DRV_VERSION); + +#define RIOCM_TX_RING_SIZE 128 +#define RIOCM_RX_RING_SIZE 128 +#define RIOCM_CONNECT_TO 3 /* connect response TO (in sec) */ + +#define RIOCM_MAX_CHNUM 0xffff /* Use full range of u16 field */ +#define RIOCM_CHNUM_AUTO 0 +#define RIOCM_MAX_EP_COUNT 0x10000 /* Max number of endpoints */ + +enum rio_cm_state { + RIO_CM_IDLE, + RIO_CM_CONNECT, + RIO_CM_CONNECTED, + RIO_CM_DISCONNECT, + RIO_CM_CHAN_BOUND, + RIO_CM_LISTEN, + RIO_CM_DESTROYING, +}; + +enum rio_cm_pkt_type { + RIO_CM_SYS = 0xaa, + RIO_CM_CHAN = 0x55, +}; + +enum rio_cm_chop { + CM_CONN_REQ, + CM_CONN_ACK, + CM_CONN_CLOSE, + CM_DATA_MSG, +}; + +struct rio_ch_base_bhdr { + u32 src_id; + u32 dst_id; +#define RIO_HDR_LETTER_MASK 0xffff0000 +#define RIO_HDR_MBOX_MASK 0x0000ffff + u8 src_mbox; + u8 dst_mbox; + u8 type; +} __attribute__((__packed__)); + +struct rio_ch_chan_hdr { + struct rio_ch_base_bhdr bhdr; + u8 ch_op; + u16 dst_ch; + u16 src_ch; + u16 msg_len; + u16 rsrvd; +} __attribute__((__packed__)); + +struct tx_req { + struct list_head node; + struct rio_dev *rdev; + void *buffer; + size_t len; +}; + +struct cm_dev { + struct list_head list; + struct rio_mport *mport; + void *rx_buf[RIOCM_RX_RING_SIZE]; + int rx_slots; + struct mutex rx_lock; + + void *tx_buf[RIOCM_TX_RING_SIZE]; + int tx_slot; + int tx_cnt; + int tx_ack_slot; + struct list_head tx_reqs; + spinlock_t tx_lock; + + struct list_head peers; + u32 npeers; + struct workqueue_struct *rx_wq; + struct work_struct rx_work; +}; + +struct chan_rx_ring { + void *buf[RIOCM_RX_RING_SIZE]; + int head; + int tail; + int count; + + /* Tracking RX buffers reported to upper level */ + void *inuse[RIOCM_RX_RING_SIZE]; + int inuse_cnt; +}; + +struct rio_channel { + u16 id; /* local channel ID */ + struct kref ref; /* channel refcount */ + struct file *filp; + struct cm_dev *cmdev; /* associated CM device object */ + struct rio_dev *rdev; /* remote RapidIO device */ + enum rio_cm_state state; + int error; + spinlock_t lock; + void *context; + u32 loc_destid; /* local destID */ + u32 rem_destid; /* remote destID */ + u16 rem_channel; /* remote channel ID */ + struct list_head accept_queue; + struct list_head ch_node; + struct completion comp; + struct completion comp_close; + struct chan_rx_ring rx_ring; +}; + +struct cm_peer { + struct list_head node; + struct rio_dev *rdev; +}; + +struct rio_cm_work { + struct work_struct work; + struct cm_dev *cm; + void *data; +}; + +struct conn_req { + struct list_head node; + u32 destid; /* requester destID */ + u16 chan; /* requester channel ID */ + struct cm_dev *cmdev; +}; + +/* + * A channel_dev structure represents a CM_CDEV + * @cdev Character device + * @dev Associated device object + */ +struct channel_dev { + struct cdev cdev; + struct device *dev; +}; + +static struct rio_channel *riocm_ch_alloc(u16 ch_num); +static void riocm_ch_free(struct kref *ref); +static int riocm_post_send(struct cm_dev *cm, struct rio_dev *rdev, + void *buffer, size_t len); +static int riocm_ch_close(struct rio_channel *ch); + +static DEFINE_SPINLOCK(idr_lock); +static DEFINE_IDR(ch_idr); + +static LIST_HEAD(cm_dev_list); +static DECLARE_RWSEM(rdev_sem); + +static struct class *dev_class; +static unsigned int dev_major; +static unsigned int dev_minor_base; +static dev_t dev_number; +static struct channel_dev riocm_cdev; + +#define is_msg_capable(src_ops, dst_ops) \ + ((src_ops & RIO_SRC_OPS_DATA_MSG) && \ + (dst_ops & RIO_DST_OPS_DATA_MSG)) +#define dev_cm_capable(dev) \ + is_msg_capable(dev->src_ops, dev->dst_ops) + +static int riocm_cmp(struct rio_channel *ch, enum rio_cm_state cmp) +{ + int ret; + + spin_lock_bh(&ch->lock); + ret = (ch->state == cmp); + spin_unlock_bh(&ch->lock); + return ret; +} + +static int riocm_cmp_exch(struct rio_channel *ch, + enum rio_cm_state cmp, enum rio_cm_state exch) +{ + int ret; + + spin_lock_bh(&ch->lock); + ret = (ch->state == cmp); + if (ret) + ch->state = exch; + spin_unlock_bh(&ch->lock); + return ret; +} + +static enum rio_cm_state riocm_exch(struct rio_channel *ch, + enum rio_cm_state exch) +{ + enum rio_cm_state old; + + spin_lock_bh(&ch->lock); + old = ch->state; + ch->state = exch; + spin_unlock_bh(&ch->lock); + return old; +} + +static struct rio_channel *riocm_get_channel(u16 nr) +{ + struct rio_channel *ch; + + spin_lock_bh(&idr_lock); + ch = idr_find(&ch_idr, nr); + if (ch) + kref_get(&ch->ref); + spin_unlock_bh(&idr_lock); + return ch; +} + +static void riocm_put_channel(struct rio_channel *ch) +{ + kref_put(&ch->ref, riocm_ch_free); +} + +static void *riocm_rx_get_msg(struct cm_dev *cm) +{ + void *msg; + int i; + + msg = rio_get_inb_message(cm->mport, cmbox); + if (msg) { + for (i = 0; i < RIOCM_RX_RING_SIZE; i++) { + if (cm->rx_buf[i] == msg) { + cm->rx_buf[i] = NULL; + cm->rx_slots++; + break; + } + } + + if (i == RIOCM_RX_RING_SIZE) + riocm_warn("no record for buffer 0x%p", msg); + } + + return msg; +} + +/* + * riocm_rx_fill - fills a ring of receive buffers for given cm device + * @cm: cm_dev object + * @nent: max number of entries to fill + * + * Returns: none + */ +static void riocm_rx_fill(struct cm_dev *cm, int nent) +{ + int i; + + if (cm->rx_slots == 0) + return; + + for (i = 0; i < RIOCM_RX_RING_SIZE && cm->rx_slots && nent; i++) { + if (cm->rx_buf[i] == NULL) { + cm->rx_buf[i] = kmalloc(RIO_MAX_MSG_SIZE, GFP_KERNEL); + if (cm->rx_buf[i] == NULL) + break; + rio_add_inb_buffer(cm->mport, cmbox, cm->rx_buf[i]); + cm->rx_slots--; + nent--; + } + } +} + +/* + * riocm_rx_free - frees all receive buffers associated with given cm device + * @cm: cm_dev object + * + * Returns: none + */ +static void riocm_rx_free(struct cm_dev *cm) +{ + int i; + + for (i = 0; i < RIOCM_RX_RING_SIZE; i++) { + if (cm->rx_buf[i] != NULL) { + kfree(cm->rx_buf[i]); + cm->rx_buf[i] = NULL; + } + } +} + +/* + * riocm_req_handler - connection request handler + * @cm: cm_dev object + * @req_data: pointer to the request packet + * + * Returns: 0 if success, or + * -EINVAL if channel is not in correct state, + * -ENODEV if cannot find a channel with specified ID, + * -ENOMEM if unable to allocate memory to store the request + */ +static int riocm_req_handler(struct cm_dev *cm, void *req_data) +{ + struct rio_channel *ch; + struct conn_req *req; + struct rio_ch_chan_hdr *hh = req_data; + u16 chnum; + + chnum = ntohs(hh->dst_ch); + + ch = riocm_get_channel(chnum); + + if (!ch) + return -ENODEV; + + if (ch->state != RIO_CM_LISTEN) { + riocm_debug(RX_CMD, "channel %d is not in listen state", chnum); + riocm_put_channel(ch); + return -EINVAL; + } + + req = kzalloc(sizeof(*req), GFP_KERNEL); + if (!req) { + riocm_put_channel(ch); + return -ENOMEM; + } + + req->destid = ntohl(hh->bhdr.src_id); + req->chan = ntohs(hh->src_ch); + req->cmdev = cm; + + spin_lock_bh(&ch->lock); + list_add_tail(&req->node, &ch->accept_queue); + spin_unlock_bh(&ch->lock); + complete(&ch->comp); + riocm_put_channel(ch); + + return 0; +} + +/* + * riocm_resp_handler - response to connection request handler + * @resp_data: pointer to the response packet + * + * Returns: 0 if success, or + * -EINVAL if channel is not in correct state, + * -ENODEV if cannot find a channel with specified ID, + */ +static int riocm_resp_handler(void *resp_data) +{ + struct rio_channel *ch; + struct rio_ch_chan_hdr *hh = resp_data; + u16 chnum; + + chnum = ntohs(hh->dst_ch); + ch = riocm_get_channel(chnum); + if (!ch) + return -ENODEV; + + if (ch->state != RIO_CM_CONNECT) { + riocm_put_channel(ch); + return -EINVAL; + } + + riocm_exch(ch, RIO_CM_CONNECTED); + ch->rem_channel = ntohs(hh->src_ch); + complete(&ch->comp); + riocm_put_channel(ch); + + return 0; +} + +/* + * riocm_close_handler - channel close request handler + * @req_data: pointer to the request packet + * + * Returns: 0 if success, or + * -ENODEV if cannot find a channel with specified ID, + * + error codes returned by riocm_ch_close. + */ +static int riocm_close_handler(void *data) +{ + struct rio_channel *ch; + struct rio_ch_chan_hdr *hh = data; + int ret; + + riocm_debug(RX_CMD, "for ch=%d", ntohs(hh->dst_ch)); + + spin_lock_bh(&idr_lock); + ch = idr_find(&ch_idr, ntohs(hh->dst_ch)); + if (!ch) { + spin_unlock_bh(&idr_lock); + return -ENODEV; + } + idr_remove(&ch_idr, ch->id); + spin_unlock_bh(&idr_lock); + + riocm_exch(ch, RIO_CM_DISCONNECT); + + ret = riocm_ch_close(ch); + if (ret) + riocm_debug(RX_CMD, "riocm_ch_close() returned %d", ret); + + return 0; +} + +/* + * rio_cm_handler - function that services request (non-data) packets + * @cm: cm_dev object + * @data: pointer to the packet + */ +static void rio_cm_handler(struct cm_dev *cm, void *data) +{ + struct rio_ch_chan_hdr *hdr; + + if (!rio_mport_is_running(cm->mport)) + goto out; + + hdr = data; + + riocm_debug(RX_CMD, "OP=%x for ch=%d from %d", + hdr->ch_op, ntohs(hdr->dst_ch), ntohs(hdr->src_ch)); + + switch (hdr->ch_op) { + case CM_CONN_REQ: + riocm_req_handler(cm, data); + break; + case CM_CONN_ACK: + riocm_resp_handler(data); + break; + case CM_CONN_CLOSE: + riocm_close_handler(data); + break; + default: + riocm_error("Invalid packet header"); + break; + } +out: + kfree(data); +} + +/* + * rio_rx_data_handler - received data packet handler + * @cm: cm_dev object + * @buf: data packet + * + * Returns: 0 if success, or + * -ENODEV if cannot find a channel with specified ID, + * -EIO if channel is not in CONNECTED state, + * -ENOMEM if channel RX queue is full (packet discarded) + */ +static int rio_rx_data_handler(struct cm_dev *cm, void *buf) +{ + struct rio_ch_chan_hdr *hdr; + struct rio_channel *ch; + + hdr = buf; + + riocm_debug(RX_DATA, "for ch=%d", ntohs(hdr->dst_ch)); + + ch = riocm_get_channel(ntohs(hdr->dst_ch)); + if (!ch) { + /* Discard data message for non-existing channel */ + kfree(buf); + return -ENODEV; + } + + /* Place pointer to the buffer into channel's RX queue */ + spin_lock(&ch->lock); + + if (ch->state != RIO_CM_CONNECTED) { + /* Channel is not ready to receive data, discard a packet */ + riocm_debug(RX_DATA, "ch=%d is in wrong state=%d", + ch->id, ch->state); + spin_unlock(&ch->lock); + kfree(buf); + riocm_put_channel(ch); + return -EIO; + } + + if (ch->rx_ring.count == RIOCM_RX_RING_SIZE) { + /* If RX ring is full, discard a packet */ + riocm_debug(RX_DATA, "ch=%d is full", ch->id); + spin_unlock(&ch->lock); + kfree(buf); + riocm_put_channel(ch); + return -ENOMEM; + } + + ch->rx_ring.buf[ch->rx_ring.head] = buf; + ch->rx_ring.head++; + ch->rx_ring.count++; + ch->rx_ring.head %= RIOCM_RX_RING_SIZE; + + complete(&ch->comp); + + spin_unlock(&ch->lock); + riocm_put_channel(ch); + + return 0; +} + +/* + * rio_ibmsg_handler - inbound message packet handler + */ +static void rio_ibmsg_handler(struct work_struct *work) +{ + struct cm_dev *cm = container_of(work, struct cm_dev, rx_work); + void *data; + struct rio_ch_chan_hdr *hdr; + + if (!rio_mport_is_running(cm->mport)) + return; + + while (1) { + mutex_lock(&cm->rx_lock); + data = riocm_rx_get_msg(cm); + if (data) + riocm_rx_fill(cm, 1); + mutex_unlock(&cm->rx_lock); + + if (data == NULL) + break; + + hdr = data; + + if (hdr->bhdr.type != RIO_CM_CHAN) { + /* For now simply discard packets other than channel */ + riocm_error("Unsupported TYPE code (0x%x). Msg dropped", + hdr->bhdr.type); + kfree(data); + continue; + } + + /* Process a channel message */ + if (hdr->ch_op == CM_DATA_MSG) + rio_rx_data_handler(cm, data); + else + rio_cm_handler(cm, data); + } +} + +static void riocm_inb_msg_event(struct rio_mport *mport, void *dev_id, + int mbox, int slot) +{ + struct cm_dev *cm = dev_id; + + if (rio_mport_is_running(cm->mport) && !work_pending(&cm->rx_work)) + queue_work(cm->rx_wq, &cm->rx_work); +} + +/* + * rio_txcq_handler - TX completion handler + * @cm: cm_dev object + * @slot: TX queue slot + * + * TX completion handler also ensures that pending request packets are placed + * into transmit queue as soon as a free slot becomes available. This is done + * to give higher priority to request packets during high intensity data flow. + */ +static void rio_txcq_handler(struct cm_dev *cm, int slot) +{ + int ack_slot; + + /* ATTN: Add TX completion notification if/when direct buffer + * transfer is implemented. At this moment only correct tracking + * of tx_count is important. + */ + riocm_debug(TX_EVENT, "for mport_%d slot %d tx_cnt %d", + cm->mport->id, slot, cm->tx_cnt); + + spin_lock(&cm->tx_lock); + ack_slot = cm->tx_ack_slot; + + if (ack_slot == slot) + riocm_debug(TX_EVENT, "slot == ack_slot"); + + while (cm->tx_cnt && ((ack_slot != slot) || + (cm->tx_cnt == RIOCM_TX_RING_SIZE))) { + + cm->tx_buf[ack_slot] = NULL; + ++ack_slot; + ack_slot &= (RIOCM_TX_RING_SIZE - 1); + cm->tx_cnt--; + } + + if (cm->tx_cnt < 0 || cm->tx_cnt > RIOCM_TX_RING_SIZE) + riocm_error("tx_cnt %d out of sync", cm->tx_cnt); + + WARN_ON((cm->tx_cnt < 0) || (cm->tx_cnt > RIOCM_TX_RING_SIZE)); + + cm->tx_ack_slot = ack_slot; + + /* + * If there are pending requests, insert them into transmit queue + */ + if (!list_empty(&cm->tx_reqs) && (cm->tx_cnt < RIOCM_TX_RING_SIZE)) { + struct tx_req *req, *_req; + int rc; + + list_for_each_entry_safe(req, _req, &cm->tx_reqs, node) { + list_del(&req->node); + cm->tx_buf[cm->tx_slot] = req->buffer; + rc = rio_add_outb_message(cm->mport, req->rdev, cmbox, + req->buffer, req->len); + kfree(req->buffer); + kfree(req); + + ++cm->tx_cnt; + ++cm->tx_slot; + cm->tx_slot &= (RIOCM_TX_RING_SIZE - 1); + if (cm->tx_cnt == RIOCM_TX_RING_SIZE) + break; + } + } + + spin_unlock(&cm->tx_lock); +} + +static void riocm_outb_msg_event(struct rio_mport *mport, void *dev_id, + int mbox, int slot) +{ + struct cm_dev *cm = dev_id; + + if (cm && rio_mport_is_running(cm->mport)) + rio_txcq_handler(cm, slot); +} + +static int riocm_queue_req(struct cm_dev *cm, struct rio_dev *rdev, + void *buffer, size_t len) +{ + unsigned long flags; + struct tx_req *treq; + + treq = kzalloc(sizeof(*treq), GFP_KERNEL); + if (treq == NULL) + return -ENOMEM; + + treq->rdev = rdev; + treq->buffer = buffer; + treq->len = len; + + spin_lock_irqsave(&cm->tx_lock, flags); + list_add_tail(&treq->node, &cm->tx_reqs); + spin_unlock_irqrestore(&cm->tx_lock, flags); + return 0; +} + +/* + * riocm_post_send - helper function that places packet into msg TX queue + * @cm: cm_dev object + * @rdev: target RapidIO device object (required by outbound msg interface) + * @buffer: pointer to a packet buffer to send + * @len: length of data to transfer + * @req: request priority flag + * + * Returns: 0 if success, or error code otherwise. + */ +static int riocm_post_send(struct cm_dev *cm, struct rio_dev *rdev, + void *buffer, size_t len) +{ + int rc; + unsigned long flags; + + spin_lock_irqsave(&cm->tx_lock, flags); + + if (cm->mport == NULL) { + rc = -ENODEV; + goto err_out; + } + + if (cm->tx_cnt == RIOCM_TX_RING_SIZE) { + riocm_debug(TX, "Tx Queue is full"); + rc = -EBUSY; + goto err_out; + } + + cm->tx_buf[cm->tx_slot] = buffer; + rc = rio_add_outb_message(cm->mport, rdev, cmbox, buffer, len); + + riocm_debug(TX, "Add buf@%p destid=%x tx_slot=%d tx_cnt=%d", + buffer, rdev->destid, cm->tx_slot, cm->tx_cnt); + + ++cm->tx_cnt; + ++cm->tx_slot; + cm->tx_slot &= (RIOCM_TX_RING_SIZE - 1); + +err_out: + spin_unlock_irqrestore(&cm->tx_lock, flags); + return rc; +} + +/* + * riocm_ch_send - sends a data packet to a remote device + * @ch_id: local channel ID + * @buf: pointer to a data buffer to send (including CM header) + * @len: length of data to transfer (including CM header) + * + * ATTN: ASSUMES THAT THE HEADER SPACE IS RESERVED PART OF THE DATA PACKET + * + * Returns: 0 if success, or + * -EINVAL if one or more input parameters is/are not valid, + * -ENODEV if cannot find a channel with specified ID, + * -EAGAIN if a channel is not in CONNECTED state, + * + error codes returned by HW send routine. + */ +static int riocm_ch_send(u16 ch_id, void *buf, int len) +{ + struct rio_channel *ch; + struct rio_ch_chan_hdr *hdr; + int ret; + + if (buf == NULL || ch_id == 0 || len == 0 || len > RIO_MAX_MSG_SIZE) + return -EINVAL; + + ch = riocm_get_channel(ch_id); + if (!ch) { + riocm_error("%s(%d) ch_%d not found", current->comm, + task_pid_nr(current), ch_id); + return -ENODEV; + } + + if (!riocm_cmp(ch, RIO_CM_CONNECTED)) { + ret = -EAGAIN; + goto err_out; + } + + /* + * Fill buffer header section with corresponding channel data + */ + hdr = buf; + + hdr->bhdr.src_id = htonl(ch->loc_destid); + hdr->bhdr.dst_id = htonl(ch->rem_destid); + hdr->bhdr.src_mbox = cmbox; + hdr->bhdr.dst_mbox = cmbox; + hdr->bhdr.type = RIO_CM_CHAN; + hdr->ch_op = CM_DATA_MSG; + hdr->dst_ch = htons(ch->rem_channel); + hdr->src_ch = htons(ch->id); + hdr->msg_len = htons((u16)len); + + /* ATTN: the function call below relies on the fact that underlying + * HW-specific add_outb_message() routine copies TX data into its own + * internal transfer buffer (true for all RIONET compatible mport + * drivers). Must be reviewed if mport driver uses the buffer directly. + */ + + ret = riocm_post_send(ch->cmdev, ch->rdev, buf, len); + if (ret) + riocm_debug(TX, "ch %d send_err=%d", ch->id, ret); +err_out: + riocm_put_channel(ch); + return ret; +} + +static int riocm_ch_free_rxbuf(struct rio_channel *ch, void *buf) +{ + int i, ret = -EINVAL; + + spin_lock_bh(&ch->lock); + + for (i = 0; i < RIOCM_RX_RING_SIZE; i++) { + if (ch->rx_ring.inuse[i] == buf) { + ch->rx_ring.inuse[i] = NULL; + ch->rx_ring.inuse_cnt--; + ret = 0; + break; + } + } + + spin_unlock_bh(&ch->lock); + + if (!ret) + kfree(buf); + + return ret; +} + +/* + * riocm_ch_receive - fetch a data packet received for the specified channel + * @ch: local channel ID + * @buf: pointer to a packet buffer + * @timeout: timeout to wait for incoming packet (in jiffies) + * + * Returns: 0 and valid buffer pointer if success, or NULL pointer and one of: + * -EAGAIN if a channel is not in CONNECTED state, + * -ENOMEM if in-use tracking queue is full, + * -ETIME if wait timeout expired, + * -EINTR if wait was interrupted. + */ +static int riocm_ch_receive(struct rio_channel *ch, void **buf, long timeout) +{ + void *rxmsg = NULL; + int i, ret = 0; + long wret; + + if (!riocm_cmp(ch, RIO_CM_CONNECTED)) { + ret = -EAGAIN; + goto out; + } + + if (ch->rx_ring.inuse_cnt == RIOCM_RX_RING_SIZE) { + /* If we do not have entries to track buffers given to upper + * layer, reject request. + */ + ret = -ENOMEM; + goto out; + } + + wret = wait_for_completion_interruptible_timeout(&ch->comp, timeout); + + riocm_debug(WAIT, "wait on %d returned %ld", ch->id, wret); + + if (!wret) + ret = -ETIME; + else if (wret == -ERESTARTSYS) + ret = -EINTR; + else + ret = riocm_cmp(ch, RIO_CM_CONNECTED) ? 0 : -ECONNRESET; + + if (ret) + goto out; + + spin_lock_bh(&ch->lock); + + rxmsg = ch->rx_ring.buf[ch->rx_ring.tail]; + ch->rx_ring.buf[ch->rx_ring.tail] = NULL; + ch->rx_ring.count--; + ch->rx_ring.tail++; + ch->rx_ring.tail %= RIOCM_RX_RING_SIZE; + ret = -ENOMEM; + + for (i = 0; i < RIOCM_RX_RING_SIZE; i++) { + if (ch->rx_ring.inuse[i] == NULL) { + ch->rx_ring.inuse[i] = rxmsg; + ch->rx_ring.inuse_cnt++; + ret = 0; + break; + } + } + + if (ret) { + /* We have no entry to store pending message: drop it */ + kfree(rxmsg); + rxmsg = NULL; + } + + spin_unlock_bh(&ch->lock); +out: + *buf = rxmsg; + return ret; +} + +/* + * riocm_ch_connect - sends a connect request to a remote device + * @loc_ch: local channel ID + * @cm: CM device to send connect request + * @peer: target RapidIO device + * @rem_ch: remote channel ID + * + * Returns: 0 if success, or + * -EINVAL if the channel is not in IDLE state, + * -EAGAIN if no connection request available immediately, + * -ETIME if ACK response timeout expired, + * -EINTR if wait for response was interrupted. + */ +static int riocm_ch_connect(u16 loc_ch, struct cm_dev *cm, + struct cm_peer *peer, u16 rem_ch) +{ + struct rio_channel *ch = NULL; + struct rio_ch_chan_hdr *hdr; + int ret; + long wret; + + ch = riocm_get_channel(loc_ch); + if (!ch) + return -ENODEV; + + if (!riocm_cmp_exch(ch, RIO_CM_IDLE, RIO_CM_CONNECT)) { + ret = -EINVAL; + goto conn_done; + } + + ch->cmdev = cm; + ch->rdev = peer->rdev; + ch->context = NULL; + ch->loc_destid = cm->mport->host_deviceid; + ch->rem_channel = rem_ch; + + /* + * Send connect request to the remote RapidIO device + */ + + hdr = kzalloc(sizeof(*hdr), GFP_KERNEL); + if (hdr == NULL) { + ret = -ENOMEM; + goto conn_done; + } + + hdr->bhdr.src_id = htonl(ch->loc_destid); + hdr->bhdr.dst_id = htonl(peer->rdev->destid); + hdr->bhdr.src_mbox = cmbox; + hdr->bhdr.dst_mbox = cmbox; + hdr->bhdr.type = RIO_CM_CHAN; + hdr->ch_op = CM_CONN_REQ; + hdr->dst_ch = htons(rem_ch); + hdr->src_ch = htons(loc_ch); + + /* ATTN: the function call below relies on the fact that underlying + * HW-specific add_outb_message() routine copies TX data into its + * internal transfer buffer. Must be reviewed if mport driver uses + * this buffer directly. + */ + ret = riocm_post_send(cm, peer->rdev, hdr, sizeof(*hdr)); + + if (ret != -EBUSY) { + kfree(hdr); + } else { + ret = riocm_queue_req(cm, peer->rdev, hdr, sizeof(*hdr)); + if (ret) + kfree(hdr); + } + + if (ret) { + riocm_cmp_exch(ch, RIO_CM_CONNECT, RIO_CM_IDLE); + goto conn_done; + } + + /* Wait for connect response from the remote device */ + wret = wait_for_completion_interruptible_timeout(&ch->comp, + RIOCM_CONNECT_TO * HZ); + riocm_debug(WAIT, "wait on %d returns %ld", ch->id, wret); + + if (!wret) + ret = -ETIME; + else if (wret == -ERESTARTSYS) + ret = -EINTR; + else + ret = riocm_cmp(ch, RIO_CM_CONNECTED) ? 0 : -1; + +conn_done: + riocm_put_channel(ch); + return ret; +} + +static int riocm_send_ack(struct rio_channel *ch) +{ + struct rio_ch_chan_hdr *hdr; + int ret; + + hdr = kzalloc(sizeof(*hdr), GFP_KERNEL); + if (hdr == NULL) + return -ENOMEM; + + hdr->bhdr.src_id = htonl(ch->loc_destid); + hdr->bhdr.dst_id = htonl(ch->rem_destid); + hdr->dst_ch = htons(ch->rem_channel); + hdr->src_ch = htons(ch->id); + hdr->bhdr.src_mbox = cmbox; + hdr->bhdr.dst_mbox = cmbox; + hdr->bhdr.type = RIO_CM_CHAN; + hdr->ch_op = CM_CONN_ACK; + + /* ATTN: the function call below relies on the fact that underlying + * add_outb_message() routine copies TX data into its internal transfer + * buffer. Review if switching to direct buffer version. + */ + ret = riocm_post_send(ch->cmdev, ch->rdev, hdr, sizeof(*hdr)); + + if (ret == -EBUSY && !riocm_queue_req(ch->cmdev, + ch->rdev, hdr, sizeof(*hdr))) + return 0; + kfree(hdr); + + if (ret) + riocm_error("send ACK to ch_%d on %s failed (ret=%d)", + ch->id, rio_name(ch->rdev), ret); + return ret; +} + +/* + * riocm_ch_accept - accept incoming connection request + * @ch_id: channel ID + * @new_ch_id: local mport device + * @timeout: wait timeout (if 0 non-blocking call, do not wait if connection + * request is not available). + * + * Returns: pointer to new channel struct if success, or error-valued pointer: + * -ENODEV - cannot find specified channel or mport, + * -EINVAL - the channel is not in IDLE state, + * -EAGAIN - no connection request available immediately (timeout=0), + * -ENOMEM - unable to allocate new channel, + * -ETIME - wait timeout expired, + * -EINTR - wait was interrupted. + */ +static struct rio_channel *riocm_ch_accept(u16 ch_id, u16 *new_ch_id, + long timeout) +{ + struct rio_channel *ch = NULL; + struct rio_channel *new_ch = NULL; + struct conn_req *req; + struct cm_peer *peer; + int found = 0; + int err = 0; + long wret; + + ch = riocm_get_channel(ch_id); + if (!ch) + return ERR_PTR(-EINVAL); + + if (!riocm_cmp(ch, RIO_CM_LISTEN)) { + err = -EINVAL; + goto err_put; + } + + /* Don't sleep if this is a non blocking call */ + if (!timeout) { + if (!try_wait_for_completion(&ch->comp)) { + err = -EAGAIN; + goto err_put; + } + } else { + riocm_debug(WAIT, "on %d", ch->id); + + wret = wait_for_completion_interruptible_timeout(&ch->comp, + timeout); + if (!wret) { + err = -ETIME; + goto err_put; + } else if (wret == -ERESTARTSYS) { + err = -EINTR; + goto err_put; + } + } + + spin_lock_bh(&ch->lock); + + if (ch->state != RIO_CM_LISTEN) { + err = -ECANCELED; + } else if (list_empty(&ch->accept_queue)) { + riocm_debug(WAIT, "on %d accept_queue is empty on completion", + ch->id); + err = -EIO; + } + + spin_unlock_bh(&ch->lock); + + if (err) { + riocm_debug(WAIT, "on %d returns %d", ch->id, err); + goto err_put; + } + + /* Create new channel for this connection */ + new_ch = riocm_ch_alloc(RIOCM_CHNUM_AUTO); + + if (IS_ERR(new_ch)) { + riocm_error("failed to get channel for new req (%ld)", + PTR_ERR(new_ch)); + err = -ENOMEM; + goto err_put; + } + + spin_lock_bh(&ch->lock); + + req = list_first_entry(&ch->accept_queue, struct conn_req, node); + list_del(&req->node); + new_ch->cmdev = ch->cmdev; + new_ch->loc_destid = ch->loc_destid; + new_ch->rem_destid = req->destid; + new_ch->rem_channel = req->chan; + + spin_unlock_bh(&ch->lock); + riocm_put_channel(ch); + kfree(req); + + down_read(&rdev_sem); + /* Find requester's device object */ + list_for_each_entry(peer, &new_ch->cmdev->peers, node) { + if (peer->rdev->destid == new_ch->rem_destid) { + riocm_debug(RX_CMD, "found matching device(%s)", + rio_name(peer->rdev)); + found = 1; + break; + } + } + up_read(&rdev_sem); + + if (!found) { + /* If peer device object not found, simply ignore the request */ + err = -ENODEV; + goto err_nodev; + } + + new_ch->rdev = peer->rdev; + new_ch->state = RIO_CM_CONNECTED; + spin_lock_init(&new_ch->lock); + + /* Acknowledge the connection request. */ + riocm_send_ack(new_ch); + + *new_ch_id = new_ch->id; + return new_ch; +err_put: + riocm_put_channel(ch); +err_nodev: + if (new_ch) { + spin_lock_bh(&idr_lock); + idr_remove(&ch_idr, new_ch->id); + spin_unlock_bh(&idr_lock); + riocm_put_channel(new_ch); + } + *new_ch_id = 0; + return ERR_PTR(err); +} + +/* + * riocm_ch_listen - puts a channel into LISTEN state + * @ch_id: channel ID + * + * Returns: 0 if success, or + * -EINVAL if the specified channel does not exists or + * is not in CHAN_BOUND state. + */ +static int riocm_ch_listen(u16 ch_id) +{ + struct rio_channel *ch = NULL; + int ret = 0; + + riocm_debug(CHOP, "(ch_%d)", ch_id); + + ch = riocm_get_channel(ch_id); + if (!ch || !riocm_cmp_exch(ch, RIO_CM_CHAN_BOUND, RIO_CM_LISTEN)) + ret = -EINVAL; + riocm_put_channel(ch); + return ret; +} + +/* + * riocm_ch_bind - associate a channel object and an mport device + * @ch_id: channel ID + * @mport_id: local mport device ID + * @context: pointer to the additional caller's context + * + * Returns: 0 if success, or + * -ENODEV if cannot find specified mport, + * -EINVAL if the specified channel does not exist or + * is not in IDLE state. + */ +static int riocm_ch_bind(u16 ch_id, u8 mport_id, void *context) +{ + struct rio_channel *ch = NULL; + struct cm_dev *cm; + int rc = -ENODEV; + + riocm_debug(CHOP, "ch_%d to mport_%d", ch_id, mport_id); + + /* Find matching cm_dev object */ + down_read(&rdev_sem); + list_for_each_entry(cm, &cm_dev_list, list) { + if ((cm->mport->id == mport_id) && + rio_mport_is_running(cm->mport)) { + rc = 0; + break; + } + } + + if (rc) + goto exit; + + ch = riocm_get_channel(ch_id); + if (!ch) { + rc = -EINVAL; + goto exit; + } + + spin_lock_bh(&ch->lock); + if (ch->state != RIO_CM_IDLE) { + spin_unlock_bh(&ch->lock); + rc = -EINVAL; + goto err_put; + } + + ch->cmdev = cm; + ch->loc_destid = cm->mport->host_deviceid; + ch->context = context; + ch->state = RIO_CM_CHAN_BOUND; + spin_unlock_bh(&ch->lock); +err_put: + riocm_put_channel(ch); +exit: + up_read(&rdev_sem); + return rc; +} + +/* + * riocm_ch_alloc - channel object allocation helper routine + * @ch_num: channel ID (1 ... RIOCM_MAX_CHNUM, 0 = automatic) + * + * Return value: pointer to newly created channel object, + * or error-valued pointer + */ +static struct rio_channel *riocm_ch_alloc(u16 ch_num) +{ + int id; + int start, end; + struct rio_channel *ch; + + ch = kzalloc(sizeof(*ch), GFP_KERNEL); + if (!ch) + return ERR_PTR(-ENOMEM); + + if (ch_num) { + /* If requested, try to obtain the specified channel ID */ + start = ch_num; + end = ch_num + 1; + } else { + /* Obtain channel ID from the dynamic allocation range */ + start = chstart; + end = RIOCM_MAX_CHNUM + 1; + } + + idr_preload(GFP_KERNEL); + spin_lock_bh(&idr_lock); + id = idr_alloc_cyclic(&ch_idr, ch, start, end, GFP_NOWAIT); + spin_unlock_bh(&idr_lock); + idr_preload_end(); + + if (id < 0) { + kfree(ch); + return ERR_PTR(id == -ENOSPC ? -EBUSY : id); + } + + ch->id = (u16)id; + ch->state = RIO_CM_IDLE; + spin_lock_init(&ch->lock); + INIT_LIST_HEAD(&ch->accept_queue); + INIT_LIST_HEAD(&ch->ch_node); + init_completion(&ch->comp); + init_completion(&ch->comp_close); + kref_init(&ch->ref); + ch->rx_ring.head = 0; + ch->rx_ring.tail = 0; + ch->rx_ring.count = 0; + ch->rx_ring.inuse_cnt = 0; + + return ch; +} + +/* + * riocm_ch_create - creates a new channel object and allocates ID for it + * @ch_num: channel ID (1 ... RIOCM_MAX_CHNUM, 0 = automatic) + * + * Allocates and initializes a new channel object. If the parameter ch_num > 0 + * and is within the valid range, riocm_ch_create tries to allocate the + * specified ID for the new channel. If ch_num = 0, channel ID will be assigned + * automatically from the range (chstart ... RIOCM_MAX_CHNUM). + * Module parameter 'chstart' defines start of an ID range available for dynamic + * allocation. Range below 'chstart' is reserved for pre-defined ID numbers. + * Available channel numbers are limited by 16-bit size of channel numbers used + * in the packet header. + * + * Return value: PTR to rio_channel structure if successful (with channel number + * updated via pointer) or error-valued pointer if error. + */ +static struct rio_channel *riocm_ch_create(u16 *ch_num) +{ + struct rio_channel *ch = NULL; + + ch = riocm_ch_alloc(*ch_num); + + if (IS_ERR(ch)) + riocm_debug(CHOP, "Failed to allocate channel %d (err=%ld)", + *ch_num, PTR_ERR(ch)); + else + *ch_num = ch->id; + + return ch; +} + +/* + * riocm_ch_free - channel object release routine + * @ref: pointer to a channel's kref structure + */ +static void riocm_ch_free(struct kref *ref) +{ + struct rio_channel *ch = container_of(ref, struct rio_channel, ref); + int i; + + riocm_debug(CHOP, "(ch_%d)", ch->id); + + if (ch->rx_ring.inuse_cnt) { + for (i = 0; + i < RIOCM_RX_RING_SIZE && ch->rx_ring.inuse_cnt; i++) { + if (ch->rx_ring.inuse[i] != NULL) { + kfree(ch->rx_ring.inuse[i]); + ch->rx_ring.inuse_cnt--; + } + } + } + + if (ch->rx_ring.count) + for (i = 0; i < RIOCM_RX_RING_SIZE && ch->rx_ring.count; i++) { + if (ch->rx_ring.buf[i] != NULL) { + kfree(ch->rx_ring.buf[i]); + ch->rx_ring.count--; + } + } + + complete(&ch->comp_close); +} + +static int riocm_send_close(struct rio_channel *ch) +{ + struct rio_ch_chan_hdr *hdr; + int ret; + + /* + * Send CH_CLOSE notification to the remote RapidIO device + */ + + hdr = kzalloc(sizeof(*hdr), GFP_KERNEL); + if (hdr == NULL) + return -ENOMEM; + + hdr->bhdr.src_id = htonl(ch->loc_destid); + hdr->bhdr.dst_id = htonl(ch->rem_destid); + hdr->bhdr.src_mbox = cmbox; + hdr->bhdr.dst_mbox = cmbox; + hdr->bhdr.type = RIO_CM_CHAN; + hdr->ch_op = CM_CONN_CLOSE; + hdr->dst_ch = htons(ch->rem_channel); + hdr->src_ch = htons(ch->id); + + /* ATTN: the function call below relies on the fact that underlying + * add_outb_message() routine copies TX data into its internal transfer + * buffer. Needs to be reviewed if switched to direct buffer mode. + */ + ret = riocm_post_send(ch->cmdev, ch->rdev, hdr, sizeof(*hdr)); + + if (ret == -EBUSY && !riocm_queue_req(ch->cmdev, ch->rdev, + hdr, sizeof(*hdr))) + return 0; + kfree(hdr); + + if (ret) + riocm_error("ch(%d) send CLOSE failed (ret=%d)", ch->id, ret); + + return ret; +} + +/* + * riocm_ch_close - closes a channel object with specified ID (by local request) + * @ch: channel to be closed + */ +static int riocm_ch_close(struct rio_channel *ch) +{ + unsigned long tmo = msecs_to_jiffies(3000); + enum rio_cm_state state; + long wret; + int ret = 0; + + riocm_debug(CHOP, "ch_%d by %s(%d)", + ch->id, current->comm, task_pid_nr(current)); + + state = riocm_exch(ch, RIO_CM_DESTROYING); + if (state == RIO_CM_CONNECTED) + riocm_send_close(ch); + + complete_all(&ch->comp); + + riocm_put_channel(ch); + wret = wait_for_completion_interruptible_timeout(&ch->comp_close, tmo); + + riocm_debug(WAIT, "wait on %d returns %ld", ch->id, wret); + + if (wret == 0) { + /* Timeout on wait occurred */ + riocm_debug(CHOP, "%s(%d) timed out waiting for ch %d", + current->comm, task_pid_nr(current), ch->id); + ret = -ETIMEDOUT; + } else if (wret == -ERESTARTSYS) { + /* Wait_for_completion was interrupted by a signal */ + riocm_debug(CHOP, "%s(%d) wait for ch %d was interrupted", + current->comm, task_pid_nr(current), ch->id); + ret = -EINTR; + } + + if (!ret) { + riocm_debug(CHOP, "ch_%d resources released", ch->id); + kfree(ch); + } else { + riocm_debug(CHOP, "failed to release ch_%d resources", ch->id); + } + + return ret; +} + +/* + * riocm_cdev_open() - Open character device + */ +static int riocm_cdev_open(struct inode *inode, struct file *filp) +{ + riocm_debug(INIT, "by %s(%d) filp=%p ", + current->comm, task_pid_nr(current), filp); + + if (list_empty(&cm_dev_list)) + return -ENODEV; + + return 0; +} + +/* + * riocm_cdev_release() - Release character device + */ +static int riocm_cdev_release(struct inode *inode, struct file *filp) +{ + struct rio_channel *ch, *_c; + unsigned int i; + LIST_HEAD(list); + + riocm_debug(EXIT, "by %s(%d) filp=%p", + current->comm, task_pid_nr(current), filp); + + /* Check if there are channels associated with this file descriptor */ + spin_lock_bh(&idr_lock); + idr_for_each_entry(&ch_idr, ch, i) { + if (ch && ch->filp == filp) { + riocm_debug(EXIT, "ch_%d not released by %s(%d)", + ch->id, current->comm, + task_pid_nr(current)); + idr_remove(&ch_idr, ch->id); + list_add(&ch->ch_node, &list); + } + } + spin_unlock_bh(&idr_lock); + + if (!list_empty(&list)) { + list_for_each_entry_safe(ch, _c, &list, ch_node) { + list_del(&ch->ch_node); + riocm_ch_close(ch); + } + } + + return 0; +} + +/* + * cm_ep_get_list_size() - Reports number of endpoints in the network + */ +static int cm_ep_get_list_size(void __user *arg) +{ + u32 __user *p = arg; + u32 mport_id; + u32 count = 0; + struct cm_dev *cm; + + if (get_user(mport_id, p)) + return -EFAULT; + if (mport_id >= RIO_MAX_MPORTS) + return -EINVAL; + + /* Find a matching cm_dev object */ + down_read(&rdev_sem); + list_for_each_entry(cm, &cm_dev_list, list) { + if (cm->mport->id == mport_id) { + count = cm->npeers; + up_read(&rdev_sem); + if (copy_to_user(arg, &count, sizeof(u32))) + return -EFAULT; + return 0; + } + } + up_read(&rdev_sem); + + return -ENODEV; +} + +/* + * cm_ep_get_list() - Returns list of attached endpoints + */ +static int cm_ep_get_list(void __user *arg) +{ + struct cm_dev *cm; + struct cm_peer *peer; + u32 info[2]; + void *buf; + u32 nent; + u32 *entry_ptr; + u32 i = 0; + int ret = 0; + + if (copy_from_user(&info, arg, sizeof(info))) + return -EFAULT; + + if (info[1] >= RIO_MAX_MPORTS || info[0] > RIOCM_MAX_EP_COUNT) + return -EINVAL; + + /* Find a matching cm_dev object */ + down_read(&rdev_sem); + list_for_each_entry(cm, &cm_dev_list, list) + if (cm->mport->id == (u8)info[1]) + goto found; + + up_read(&rdev_sem); + return -ENODEV; + +found: + nent = min(info[0], cm->npeers); + buf = kcalloc(nent + 2, sizeof(u32), GFP_KERNEL); + if (!buf) { + up_read(&rdev_sem); + return -ENOMEM; + } + + entry_ptr = (u32 *)((uintptr_t)buf + 2*sizeof(u32)); + + list_for_each_entry(peer, &cm->peers, node) { + *entry_ptr = (u32)peer->rdev->destid; + entry_ptr++; + if (++i == nent) + break; + } + up_read(&rdev_sem); + + ((u32 *)buf)[0] = i; /* report an updated number of entries */ + ((u32 *)buf)[1] = info[1]; /* put back an mport ID */ + if (copy_to_user(arg, buf, sizeof(u32) * (info[0] + 2))) + ret = -EFAULT; + + kfree(buf); + return ret; +} + +/* + * cm_mport_get_list() - Returns list of available local mport devices + */ +static int cm_mport_get_list(void __user *arg) +{ + int ret = 0; + u32 entries; + void *buf; + struct cm_dev *cm; + u32 *entry_ptr; + int count = 0; + + if (copy_from_user(&entries, arg, sizeof(entries))) + return -EFAULT; + if (entries == 0 || entries > RIO_MAX_MPORTS) + return -EINVAL; + buf = kcalloc(entries + 1, sizeof(u32), GFP_KERNEL); + if (!buf) + return -ENOMEM; + + /* Scan all registered cm_dev objects */ + entry_ptr = (u32 *)((uintptr_t)buf + sizeof(u32)); + down_read(&rdev_sem); + list_for_each_entry(cm, &cm_dev_list, list) { + if (count++ < entries) { + *entry_ptr = (cm->mport->id << 16) | + cm->mport->host_deviceid; + entry_ptr++; + } + } + up_read(&rdev_sem); + + *((u32 *)buf) = count; /* report a real number of entries */ + if (copy_to_user(arg, buf, sizeof(u32) * (count + 1))) + ret = -EFAULT; + + kfree(buf); + return ret; +} + +/* + * cm_chan_create() - Create a message exchange channel + */ +static int cm_chan_create(struct file *filp, void __user *arg) +{ + u16 __user *p = arg; + u16 ch_num; + struct rio_channel *ch; + + if (get_user(ch_num, p)) + return -EFAULT; + + riocm_debug(CHOP, "ch_%d requested by %s(%d)", + ch_num, current->comm, task_pid_nr(current)); + ch = riocm_ch_create(&ch_num); + if (IS_ERR(ch)) + return PTR_ERR(ch); + + ch->filp = filp; + riocm_debug(CHOP, "ch_%d created by %s(%d)", + ch_num, current->comm, task_pid_nr(current)); + return put_user(ch_num, p); +} + +/* + * cm_chan_close() - Close channel + * @filp: Pointer to file object + * @arg: Channel to close + */ +static int cm_chan_close(struct file *filp, void __user *arg) +{ + u16 __user *p = arg; + u16 ch_num; + struct rio_channel *ch; + + if (get_user(ch_num, p)) + return -EFAULT; + + riocm_debug(CHOP, "ch_%d by %s(%d)", + ch_num, current->comm, task_pid_nr(current)); + + spin_lock_bh(&idr_lock); + ch = idr_find(&ch_idr, ch_num); + if (!ch) { + spin_unlock_bh(&idr_lock); + return 0; + } + if (ch->filp != filp) { + spin_unlock_bh(&idr_lock); + return -EINVAL; + } + idr_remove(&ch_idr, ch->id); + spin_unlock_bh(&idr_lock); + + return riocm_ch_close(ch); +} + +/* + * cm_chan_bind() - Bind channel + * @arg: Channel number + */ +static int cm_chan_bind(void __user *arg) +{ + struct rio_cm_channel chan; + + if (copy_from_user(&chan, arg, sizeof(chan))) + return -EFAULT; + if (chan.mport_id >= RIO_MAX_MPORTS) + return -EINVAL; + + return riocm_ch_bind(chan.id, chan.mport_id, NULL); +} + +/* + * cm_chan_listen() - Listen on channel + * @arg: Channel number + */ +static int cm_chan_listen(void __user *arg) +{ + u16 __user *p = arg; + u16 ch_num; + + if (get_user(ch_num, p)) + return -EFAULT; + + return riocm_ch_listen(ch_num); +} + +/* + * cm_chan_accept() - Accept incoming connection + * @filp: Pointer to file object + * @arg: Channel number + */ +static int cm_chan_accept(struct file *filp, void __user *arg) +{ + struct rio_cm_accept param; + long accept_to; + struct rio_channel *ch; + + if (copy_from_user(¶m, arg, sizeof(param))) + return -EFAULT; + + riocm_debug(CHOP, "on ch_%d by %s(%d)", + param.ch_num, current->comm, task_pid_nr(current)); + + accept_to = param.wait_to ? + msecs_to_jiffies(param.wait_to) : 0; + + ch = riocm_ch_accept(param.ch_num, ¶m.ch_num, accept_to); + if (IS_ERR(ch)) + return PTR_ERR(ch); + ch->filp = filp; + + riocm_debug(CHOP, "new ch_%d for %s(%d)", + ch->id, current->comm, task_pid_nr(current)); + + if (copy_to_user(arg, ¶m, sizeof(param))) + return -EFAULT; + return 0; +} + +/* + * cm_chan_connect() - Connect on channel + * @arg: Channel information + */ +static int cm_chan_connect(void __user *arg) +{ + struct rio_cm_channel chan; + struct cm_dev *cm; + struct cm_peer *peer; + int ret = -ENODEV; + + if (copy_from_user(&chan, arg, sizeof(chan))) + return -EFAULT; + if (chan.mport_id >= RIO_MAX_MPORTS) + return -EINVAL; + + down_read(&rdev_sem); + + /* Find matching cm_dev object */ + list_for_each_entry(cm, &cm_dev_list, list) { + if (cm->mport->id == chan.mport_id) { + ret = 0; + break; + } + } + + if (ret) + goto err_out; + + if (chan.remote_destid >= RIO_ANY_DESTID(cm->mport->sys_size)) { + ret = -EINVAL; + goto err_out; + } + + /* Find corresponding RapidIO endpoint device object */ + ret = -ENODEV; + + list_for_each_entry(peer, &cm->peers, node) { + if (peer->rdev->destid == chan.remote_destid) { + ret = 0; + break; + } + } + + if (ret) + goto err_out; + + up_read(&rdev_sem); + + return riocm_ch_connect(chan.id, cm, peer, chan.remote_channel); +err_out: + up_read(&rdev_sem); + return ret; +} + +/* + * cm_chan_msg_send() - Send a message through channel + * @arg: Outbound message information + */ +static int cm_chan_msg_send(void __user *arg) +{ + struct rio_cm_msg msg; + void *buf; + int ret = 0; + + if (copy_from_user(&msg, arg, sizeof(msg))) + return -EFAULT; + if (msg.size > RIO_MAX_MSG_SIZE) + return -EINVAL; + + buf = kmalloc(msg.size, GFP_KERNEL); + if (!buf) + return -ENOMEM; + + if (copy_from_user(buf, (void __user *)(uintptr_t)msg.msg, msg.size)) { + ret = -EFAULT; + goto out; + } + + ret = riocm_ch_send(msg.ch_num, buf, msg.size); +out: + kfree(buf); + return ret; +} + +/* + * cm_chan_msg_rcv() - Receive a message through channel + * @arg: Inbound message information + */ +static int cm_chan_msg_rcv(void __user *arg) +{ + struct rio_cm_msg msg; + struct rio_channel *ch; + void *buf; + long rxto; + int ret = 0, msg_size; + + if (copy_from_user(&msg, arg, sizeof(msg))) + return -EFAULT; + + if (msg.ch_num == 0 || msg.size == 0) + return -EINVAL; + + ch = riocm_get_channel(msg.ch_num); + if (!ch) + return -ENODEV; + + rxto = msg.rxto ? msecs_to_jiffies(msg.rxto) : MAX_SCHEDULE_TIMEOUT; + + ret = riocm_ch_receive(ch, &buf, rxto); + if (ret) + goto out; + + msg_size = min(msg.size, (u16)(RIO_MAX_MSG_SIZE)); + + if (copy_to_user((void __user *)(uintptr_t)msg.msg, buf, msg_size)) + ret = -EFAULT; + + riocm_ch_free_rxbuf(ch, buf); +out: + riocm_put_channel(ch); + return ret; +} + +/* + * riocm_cdev_ioctl() - IOCTL requests handler + */ +static long +riocm_cdev_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) +{ + switch (cmd) { + case RIO_CM_EP_GET_LIST_SIZE: + return cm_ep_get_list_size((void __user *)arg); + case RIO_CM_EP_GET_LIST: + return cm_ep_get_list((void __user *)arg); + case RIO_CM_CHAN_CREATE: + return cm_chan_create(filp, (void __user *)arg); + case RIO_CM_CHAN_CLOSE: + return cm_chan_close(filp, (void __user *)arg); + case RIO_CM_CHAN_BIND: + return cm_chan_bind((void __user *)arg); + case RIO_CM_CHAN_LISTEN: + return cm_chan_listen((void __user *)arg); + case RIO_CM_CHAN_ACCEPT: + return cm_chan_accept(filp, (void __user *)arg); + case RIO_CM_CHAN_CONNECT: + return cm_chan_connect((void __user *)arg); + case RIO_CM_CHAN_SEND: + return cm_chan_msg_send((void __user *)arg); + case RIO_CM_CHAN_RECEIVE: + return cm_chan_msg_rcv((void __user *)arg); + case RIO_CM_MPORT_GET_LIST: + return cm_mport_get_list((void __user *)arg); + default: + break; + } + + return -EINVAL; +} + +static const struct file_operations riocm_cdev_fops = { + .owner = THIS_MODULE, + .open = riocm_cdev_open, + .release = riocm_cdev_release, + .unlocked_ioctl = riocm_cdev_ioctl, +}; + +/* + * riocm_add_dev - add new remote RapidIO device into channel management core + * @dev: device object associated with RapidIO device + * @sif: subsystem interface + * + * Adds the specified RapidIO device (if applicable) into peers list of + * the corresponding channel management device (cm_dev). + */ +static int riocm_add_dev(struct device *dev, struct subsys_interface *sif) +{ + struct cm_peer *peer; + struct rio_dev *rdev = to_rio_dev(dev); + struct cm_dev *cm; + + /* Check if the remote device has capabilities required to support CM */ + if (!dev_cm_capable(rdev)) + return 0; + + riocm_debug(RDEV, "(%s)", rio_name(rdev)); + + peer = kmalloc(sizeof(*peer), GFP_KERNEL); + if (!peer) + return -ENOMEM; + + /* Find a corresponding cm_dev object */ + down_write(&rdev_sem); + list_for_each_entry(cm, &cm_dev_list, list) { + if (cm->mport == rdev->net->hport) + goto found; + } + + up_write(&rdev_sem); + kfree(peer); + return -ENODEV; + +found: + peer->rdev = rdev; + list_add_tail(&peer->node, &cm->peers); + cm->npeers++; + + up_write(&rdev_sem); + return 0; +} + +/* + * riocm_remove_dev - remove remote RapidIO device from channel management core + * @dev: device object associated with RapidIO device + * @sif: subsystem interface + * + * Removes the specified RapidIO device (if applicable) from peers list of + * the corresponding channel management device (cm_dev). + */ +static void riocm_remove_dev(struct device *dev, struct subsys_interface *sif) +{ + struct rio_dev *rdev = to_rio_dev(dev); + struct cm_dev *cm; + struct cm_peer *peer; + struct rio_channel *ch, *_c; + unsigned int i; + bool found = false; + LIST_HEAD(list); + + /* Check if the remote device has capabilities required to support CM */ + if (!dev_cm_capable(rdev)) + return; + + riocm_debug(RDEV, "(%s)", rio_name(rdev)); + + /* Find matching cm_dev object */ + down_write(&rdev_sem); + list_for_each_entry(cm, &cm_dev_list, list) { + if (cm->mport == rdev->net->hport) { + found = true; + break; + } + } + + if (!found) { + up_write(&rdev_sem); + return; + } + + /* Remove remote device from the list of peers */ + found = false; + list_for_each_entry(peer, &cm->peers, node) { + if (peer->rdev == rdev) { + riocm_debug(RDEV, "removing peer %s", rio_name(rdev)); + found = true; + list_del(&peer->node); + cm->npeers--; + kfree(peer); + break; + } + } + + up_write(&rdev_sem); + + if (!found) + return; + + /* + * Release channels associated with this peer + */ + + spin_lock_bh(&idr_lock); + idr_for_each_entry(&ch_idr, ch, i) { + if (ch && ch->rdev == rdev) { + if (atomic_read(&rdev->state) != RIO_DEVICE_SHUTDOWN) + riocm_exch(ch, RIO_CM_DISCONNECT); + idr_remove(&ch_idr, ch->id); + list_add(&ch->ch_node, &list); + } + } + spin_unlock_bh(&idr_lock); + + if (!list_empty(&list)) { + list_for_each_entry_safe(ch, _c, &list, ch_node) { + list_del(&ch->ch_node); + riocm_ch_close(ch); + } + } +} + +/* + * riocm_cdev_add() - Create rio_cm char device + * @devno: device number assigned to device (MAJ + MIN) + */ +static int riocm_cdev_add(dev_t devno) +{ + int ret; + + cdev_init(&riocm_cdev.cdev, &riocm_cdev_fops); + riocm_cdev.cdev.owner = THIS_MODULE; + ret = cdev_add(&riocm_cdev.cdev, devno, 1); + if (ret < 0) { + riocm_error("Cannot register a device with error %d", ret); + return ret; + } + + riocm_cdev.dev = device_create(dev_class, NULL, devno, NULL, DEV_NAME); + if (IS_ERR(riocm_cdev.dev)) { + cdev_del(&riocm_cdev.cdev); + return PTR_ERR(riocm_cdev.dev); + } + + riocm_debug(MPORT, "Added %s cdev(%d:%d)", + DEV_NAME, MAJOR(devno), MINOR(devno)); + + return 0; +} + +/* + * riocm_add_mport - add new local mport device into channel management core + * @dev: device object associated with mport + * @class_intf: class interface + * + * When a new mport device is added, CM immediately reserves inbound and + * outbound RapidIO mailboxes that will be used. + */ +static int riocm_add_mport(struct device *dev, + struct class_interface *class_intf) +{ + int rc; + int i; + struct cm_dev *cm; + struct rio_mport *mport = to_rio_mport(dev); + + riocm_debug(MPORT, "add mport %s", mport->name); + + cm = kzalloc(sizeof(*cm), GFP_KERNEL); + if (!cm) + return -ENOMEM; + + cm->mport = mport; + + rc = rio_request_outb_mbox(mport, cm, cmbox, + RIOCM_TX_RING_SIZE, riocm_outb_msg_event); + if (rc) { + riocm_error("failed to allocate OBMBOX_%d on %s", + cmbox, mport->name); + kfree(cm); + return -ENODEV; + } + + rc = rio_request_inb_mbox(mport, cm, cmbox, + RIOCM_RX_RING_SIZE, riocm_inb_msg_event); + if (rc) { + riocm_error("failed to allocate IBMBOX_%d on %s", + cmbox, mport->name); + rio_release_outb_mbox(mport, cmbox); + kfree(cm); + return -ENODEV; + } + + /* + * Allocate and register inbound messaging buffers to be ready + * to receive channel and system management requests + */ + for (i = 0; i < RIOCM_RX_RING_SIZE; i++) + cm->rx_buf[i] = NULL; + + cm->rx_slots = RIOCM_RX_RING_SIZE; + mutex_init(&cm->rx_lock); + riocm_rx_fill(cm, RIOCM_RX_RING_SIZE); + cm->rx_wq = create_workqueue(DRV_NAME "/rxq"); + INIT_WORK(&cm->rx_work, rio_ibmsg_handler); + + cm->tx_slot = 0; + cm->tx_cnt = 0; + cm->tx_ack_slot = 0; + spin_lock_init(&cm->tx_lock); + + INIT_LIST_HEAD(&cm->peers); + cm->npeers = 0; + INIT_LIST_HEAD(&cm->tx_reqs); + + down_write(&rdev_sem); + list_add_tail(&cm->list, &cm_dev_list); + up_write(&rdev_sem); + + return 0; +} + +/* + * riocm_remove_mport - remove local mport device from channel management core + * @dev: device object associated with mport + * @class_intf: class interface + * + * Removes a local mport device from the list of registered devices that provide + * channel management services. Returns an error if the specified mport is not + * registered with the CM core. + */ +static void riocm_remove_mport(struct device *dev, + struct class_interface *class_intf) +{ + struct rio_mport *mport = to_rio_mport(dev); + struct cm_dev *cm; + struct cm_peer *peer, *temp; + struct rio_channel *ch, *_c; + unsigned int i; + bool found = false; + LIST_HEAD(list); + + riocm_debug(MPORT, "%s", mport->name); + + /* Find a matching cm_dev object */ + down_write(&rdev_sem); + list_for_each_entry(cm, &cm_dev_list, list) { + if (cm->mport == mport) { + list_del(&cm->list); + found = true; + break; + } + } + up_write(&rdev_sem); + if (!found) + return; + + flush_workqueue(cm->rx_wq); + destroy_workqueue(cm->rx_wq); + + /* Release channels bound to this mport */ + spin_lock_bh(&idr_lock); + idr_for_each_entry(&ch_idr, ch, i) { + if (ch->cmdev == cm) { + riocm_debug(RDEV, "%s drop ch_%d", + mport->name, ch->id); + idr_remove(&ch_idr, ch->id); + list_add(&ch->ch_node, &list); + } + } + spin_unlock_bh(&idr_lock); + + if (!list_empty(&list)) { + list_for_each_entry_safe(ch, _c, &list, ch_node) { + list_del(&ch->ch_node); + riocm_ch_close(ch); + } + } + + rio_release_inb_mbox(mport, cmbox); + rio_release_outb_mbox(mport, cmbox); + + /* Remove and free peer entries */ + if (!list_empty(&cm->peers)) + riocm_debug(RDEV, "ATTN: peer list not empty"); + list_for_each_entry_safe(peer, temp, &cm->peers, node) { + riocm_debug(RDEV, "removing peer %s", rio_name(peer->rdev)); + list_del(&peer->node); + kfree(peer); + } + + riocm_rx_free(cm); + kfree(cm); + riocm_debug(MPORT, "%s done", mport->name); +} + +static int rio_cm_shutdown(struct notifier_block *nb, unsigned long code, + void *unused) +{ + struct rio_channel *ch; + unsigned int i; + + riocm_debug(EXIT, "."); + + spin_lock_bh(&idr_lock); + idr_for_each_entry(&ch_idr, ch, i) { + riocm_debug(EXIT, "close ch %d", ch->id); + if (ch->state == RIO_CM_CONNECTED) + riocm_send_close(ch); + } + spin_unlock_bh(&idr_lock); + + return NOTIFY_DONE; +} + +/* + * riocm_interface handles addition/removal of remote RapidIO devices + */ +static struct subsys_interface riocm_interface = { + .name = "rio_cm", + .subsys = &rio_bus_type, + .add_dev = riocm_add_dev, + .remove_dev = riocm_remove_dev, +}; + +/* + * rio_mport_interface handles addition/removal local mport devices + */ +static struct class_interface rio_mport_interface __refdata = { + .class = &rio_mport_class, + .add_dev = riocm_add_mport, + .remove_dev = riocm_remove_mport, +}; + +static struct notifier_block rio_cm_notifier = { + .notifier_call = rio_cm_shutdown, +}; + +static int __init riocm_init(void) +{ + int ret; + + /* Create device class needed by udev */ + dev_class = class_create(THIS_MODULE, DRV_NAME); + if (IS_ERR(dev_class)) { + riocm_error("Cannot create " DRV_NAME " class"); + return PTR_ERR(dev_class); + } + + ret = alloc_chrdev_region(&dev_number, 0, 1, DRV_NAME); + if (ret) { + class_destroy(dev_class); + return ret; + } + + dev_major = MAJOR(dev_number); + dev_minor_base = MINOR(dev_number); + riocm_debug(INIT, "Registered class with %d major", dev_major); + + /* + * Register as rapidio_port class interface to get notifications about + * mport additions and removals. + */ + ret = class_interface_register(&rio_mport_interface); + if (ret) { + riocm_error("class_interface_register error: %d", ret); + goto err_reg; + } + + /* + * Register as RapidIO bus interface to get notifications about + * addition/removal of remote RapidIO devices. + */ + ret = subsys_interface_register(&riocm_interface); + if (ret) { + riocm_error("subsys_interface_register error: %d", ret); + goto err_cl; + } + + ret = register_reboot_notifier(&rio_cm_notifier); + if (ret) { + riocm_error("failed to register reboot notifier (err=%d)", ret); + goto err_sif; + } + + ret = riocm_cdev_add(dev_number); + if (ret) { + unregister_reboot_notifier(&rio_cm_notifier); + ret = -ENODEV; + goto err_sif; + } + + return 0; +err_sif: + subsys_interface_unregister(&riocm_interface); +err_cl: + class_interface_unregister(&rio_mport_interface); +err_reg: + unregister_chrdev_region(dev_number, 1); + class_destroy(dev_class); + return ret; +} + +static void __exit riocm_exit(void) +{ + riocm_debug(EXIT, "enter"); + unregister_reboot_notifier(&rio_cm_notifier); + subsys_interface_unregister(&riocm_interface); + class_interface_unregister(&rio_mport_interface); + idr_destroy(&ch_idr); + + device_unregister(riocm_cdev.dev); + cdev_del(&(riocm_cdev.cdev)); + + class_destroy(dev_class); + unregister_chrdev_region(dev_number, 1); +} + +late_initcall(riocm_init); +module_exit(riocm_exit); |