// SPDX-License-Identifier: GPL-2.0-or-later
/*
* rio_cm - RapidIO Channelized Messaging Driver
*
* Copyright 2013-2016 Integrated Device Technology, Inc.
* Copyright (c) 2015, Prodrive Technologies
* Copyright (c) 2015, RapidIO Trade Association
*/
#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;
struct rio_channel *new_ch;
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);
ch = NULL;
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_put_new_ch;
}
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_new_ch:
spin_lock_bh(&idr_lock);
idr_remove(&ch_idr, new_ch->id);
spin_unlock_bh(&idr_lock);
riocm_put_channel(new_ch);
err_put:
if (ch)
riocm_put_channel(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)
return -EINVAL;
if (!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;
if (copy_from_user(&msg, arg, sizeof(msg)))
return -EFAULT;
if (msg.size > RIO_MAX_MSG_SIZE)
return -EINVAL;
buf = memdup_user((void __user *)(uintptr_t)msg.msg, msg.size);
if (IS_ERR(buf))
return PTR_ERR(buf);
ret = riocm_ch_send(msg.ch_num, buf, msg.size);
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");
if (!cm->rx_wq) {
riocm_error("failed to allocate IBMBOX_%d on %s",
cmbox, mport->name);
rio_release_outb_mbox(mport, cmbox);
kfree(cm);
return -ENOMEM;
}
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;
LIST_HEAD(list);
riocm_debug(EXIT, ".");
/*
* If there are any channels left in connected state send
* close notification to the connection partner.
* First build a list of channels that require a closing
* notification because function riocm_send_close() should
* be called outside of spinlock protected code.
*/
spin_lock_bh(&idr_lock);
idr_for_each_entry(&ch_idr, ch, i) {
if (ch->state == RIO_CM_CONNECTED) {
riocm_debug(EXIT, "close ch %d", ch->id);
idr_remove(&ch_idr, ch->id);
list_add(&ch->ch_node, &list);
}
}
spin_unlock_bh(&idr_lock);
list_for_each_entry(ch, &list, ch_node)
riocm_send_close(ch);
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);