/* * This file is provided under a dual BSD/GPLv2 license. When using or * redistributing this file, you may do so under either license. * * GPL LICENSE SUMMARY * * Copyright(c) 2012 Intel Corporation. All rights reserved. * * This program is free software; you can redistribute it and/or modify * it under the terms of version 2 of the GNU General Public License as * published by the Free Software Foundation. * * BSD LICENSE * * Copyright(c) 2012 Intel Corporation. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * * Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * Redistributions in binary form must reproduce the above copy * notice, this list of conditions and the following disclaimer in * the documentation and/or other materials provided with the * distribution. * * Neither the name of Intel Corporation nor the names of its * contributors may be used to endorse or promote products derived * from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. * * Intel PCIe NTB Linux driver * * Contact Information: * Jon Mason */ #include #include #include #include #include #include #include #include #include #include #include #include #include "ntb_hw.h" #define NTB_TRANSPORT_VERSION 3 static unsigned int transport_mtu = 0x401E; module_param(transport_mtu, uint, 0644); MODULE_PARM_DESC(transport_mtu, "Maximum size of NTB transport packets"); static unsigned char max_num_clients; module_param(max_num_clients, byte, 0644); MODULE_PARM_DESC(max_num_clients, "Maximum number of NTB transport clients"); static unsigned int copy_bytes = 1024; module_param(copy_bytes, uint, 0644); MODULE_PARM_DESC(copy_bytes, "Threshold under which NTB will use the CPU to copy instead of DMA"); struct ntb_queue_entry { /* ntb_queue list reference */ struct list_head entry; /* pointers to data to be transfered */ void *cb_data; void *buf; unsigned int len; unsigned int flags; struct ntb_transport_qp *qp; union { struct ntb_payload_header __iomem *tx_hdr; struct ntb_payload_header *rx_hdr; }; unsigned int index; }; struct ntb_rx_info { unsigned int entry; }; struct ntb_transport_qp { struct ntb_transport *transport; struct ntb_device *ndev; void *cb_data; struct dma_chan *dma_chan; bool client_ready; bool qp_link; u8 qp_num; /* Only 64 QP's are allowed. 0-63 */ struct ntb_rx_info __iomem *rx_info; struct ntb_rx_info *remote_rx_info; void (*tx_handler) (struct ntb_transport_qp *qp, void *qp_data, void *data, int len); struct list_head tx_free_q; spinlock_t ntb_tx_free_q_lock; void __iomem *tx_mw; dma_addr_t tx_mw_phys; unsigned int tx_index; unsigned int tx_max_entry; unsigned int tx_max_frame; void (*rx_handler) (struct ntb_transport_qp *qp, void *qp_data, void *data, int len); struct tasklet_struct rx_work; struct list_head rx_pend_q; struct list_head rx_free_q; spinlock_t ntb_rx_pend_q_lock; spinlock_t ntb_rx_free_q_lock; void *rx_buff; unsigned int rx_index; unsigned int rx_max_entry; unsigned int rx_max_frame; dma_cookie_t last_cookie; void (*event_handler) (void *data, int status); struct delayed_work link_work; struct work_struct link_cleanup; struct dentry *debugfs_dir; struct dentry *debugfs_stats; /* Stats */ u64 rx_bytes; u64 rx_pkts; u64 rx_ring_empty; u64 rx_err_no_buf; u64 rx_err_oflow; u64 rx_err_ver; u64 rx_memcpy; u64 rx_async; u64 tx_bytes; u64 tx_pkts; u64 tx_ring_full; u64 tx_err_no_buf; u64 tx_memcpy; u64 tx_async; }; struct ntb_transport_mw { size_t size; void *virt_addr; dma_addr_t dma_addr; }; struct ntb_transport_client_dev { struct list_head entry; struct device dev; }; struct ntb_transport { struct list_head entry; struct list_head client_devs; struct ntb_device *ndev; struct ntb_transport_mw *mw; struct ntb_transport_qp *qps; unsigned int max_qps; unsigned long qp_bitmap; bool transport_link; struct delayed_work link_work; struct work_struct link_cleanup; }; enum { DESC_DONE_FLAG = 1 << 0, LINK_DOWN_FLAG = 1 << 1, }; struct ntb_payload_header { unsigned int ver; unsigned int len; unsigned int flags; }; enum { VERSION = 0, QP_LINKS, NUM_QPS, NUM_MWS, MW0_SZ_HIGH, MW0_SZ_LOW, MW1_SZ_HIGH, MW1_SZ_LOW, MAX_SPAD, }; #define QP_TO_MW(ndev, qp) ((qp) % ntb_max_mw(ndev)) #define NTB_QP_DEF_NUM_ENTRIES 100 #define NTB_LINK_DOWN_TIMEOUT 10 static int ntb_match_bus(struct device *dev, struct device_driver *drv) { return !strncmp(dev_name(dev), drv->name, strlen(drv->name)); } static int ntb_client_probe(struct device *dev) { const struct ntb_client *drv = container_of(dev->driver, struct ntb_client, driver); struct pci_dev *pdev = container_of(dev->parent, struct pci_dev, dev); int rc = -EINVAL; get_device(dev); if (drv && drv->probe) rc = drv->probe(pdev); if (rc) put_device(dev); return rc; } static int ntb_client_remove(struct device *dev) { const struct ntb_client *drv = container_of(dev->driver, struct ntb_client, driver); struct pci_dev *pdev = container_of(dev->parent, struct pci_dev, dev); if (drv && drv->remove) drv->remove(pdev); put_device(dev); return 0; } static struct bus_type ntb_bus_type = { .name = "ntb_bus", .match = ntb_match_bus, .probe = ntb_client_probe, .remove = ntb_client_remove, }; static LIST_HEAD(ntb_transport_list); static int ntb_bus_init(struct ntb_transport *nt) { if (list_empty(&ntb_transport_list)) { int rc = bus_register(&ntb_bus_type); if (rc) return rc; } list_add(&nt->entry, &ntb_transport_list); return 0; } static void ntb_bus_remove(struct ntb_transport *nt) { struct ntb_transport_client_dev *client_dev, *cd; list_for_each_entry_safe(client_dev, cd, &nt->client_devs, entry) { dev_err(client_dev->dev.parent, "%s still attached to bus, removing\n", dev_name(&client_dev->dev)); list_del(&client_dev->entry); device_unregister(&client_dev->dev); } list_del(&nt->entry); if (list_empty(&ntb_transport_list)) bus_unregister(&ntb_bus_type); } static void ntb_client_release(struct device *dev) { struct ntb_transport_client_dev *client_dev; client_dev = container_of(dev, struct ntb_transport_client_dev, dev); kfree(client_dev); } /** * ntb_unregister_client_dev - Unregister NTB client device * @device_name: Name of NTB client device * * Unregister an NTB client device with the NTB transport layer */ void ntb_unregister_client_dev(char *device_name) { struct ntb_transport_client_dev *client, *cd; struct ntb_transport *nt; list_for_each_entry(nt, &ntb_transport_list, entry) list_for_each_entry_safe(client, cd, &nt->client_devs, entry) if (!strncmp(dev_name(&client->dev), device_name, strlen(device_name))) { list_del(&client->entry); device_unregister(&client->dev); } } EXPORT_SYMBOL_GPL(ntb_unregister_client_dev); /** * ntb_register_client_dev - Register NTB client device * @device_name: Name of NTB client device * * Register an NTB client device with the NTB transport layer */ int ntb_register_client_dev(char *device_name) { struct ntb_transport_client_dev *client_dev; struct ntb_transport *nt; int rc, i = 0; if (list_empty(&ntb_transport_list)) return -ENODEV; list_for_each_entry(nt, &ntb_transport_list, entry) { struct device *dev; client_dev = kzalloc(sizeof(struct ntb_transport_client_dev), GFP_KERNEL); if (!client_dev) { rc = -ENOMEM; goto err; } dev = &client_dev->dev; /* setup and register client devices */ dev_set_name(dev, "%s%d", device_name, i); dev->bus = &ntb_bus_type; dev->release = ntb_client_release; dev->parent = &ntb_query_pdev(nt->ndev)->dev; rc = device_register(dev); if (rc) { kfree(client_dev); goto err; } list_add_tail(&client_dev->entry, &nt->client_devs); i++; } return 0; err: ntb_unregister_client_dev(device_name); return rc; } EXPORT_SYMBOL_GPL(ntb_register_client_dev); /** * ntb_register_client - Register NTB client driver * @drv: NTB client driver to be registered * * Register an NTB client driver with the NTB transport layer * * RETURNS: An appropriate -ERRNO error value on error, or zero for success. */ int ntb_register_client(struct ntb_client *drv) { drv->driver.bus = &ntb_bus_type; if (list_empty(&ntb_transport_list)) return -ENODEV; return driver_register(&drv->driver); } EXPORT_SYMBOL_GPL(ntb_register_client); /** * ntb_unregister_client - Unregister NTB client driver * @drv: NTB client driver to be unregistered * * Unregister an NTB client driver with the NTB transport layer * * RETURNS: An appropriate -ERRNO error value on error, or zero for success. */ void ntb_unregister_client(struct ntb_client *drv) { driver_unregister(&drv->driver); } EXPORT_SYMBOL_GPL(ntb_unregister_client); static ssize_t debugfs_read(struct file *filp, char __user *ubuf, size_t count, loff_t *offp) { struct ntb_transport_qp *qp; char *buf; ssize_t ret, out_offset, out_count; out_count = 1000; buf = kmalloc(out_count, GFP_KERNEL); if (!buf) return -ENOMEM; qp = filp->private_data; out_offset = 0; out_offset += snprintf(buf + out_offset, out_count - out_offset, "NTB QP stats\n"); out_offset += snprintf(buf + out_offset, out_count - out_offset, "rx_bytes - \t%llu\n", qp->rx_bytes); out_offset += snprintf(buf + out_offset, out_count - out_offset, "rx_pkts - \t%llu\n", qp->rx_pkts); out_offset += snprintf(buf + out_offset, out_count - out_offset, "rx_memcpy - \t%llu\n", qp->rx_memcpy); out_offset += snprintf(buf + out_offset, out_count - out_offset, "rx_async - \t%llu\n", qp->rx_async); out_offset += snprintf(buf + out_offset, out_count - out_offset, "rx_ring_empty - %llu\n", qp->rx_ring_empty); out_offset += snprintf(buf + out_offset, out_count - out_offset, "rx_err_no_buf - %llu\n", qp->rx_err_no_buf); out_offset += snprintf(buf + out_offset, out_count - out_offset, "rx_err_oflow - \t%llu\n", qp->rx_err_oflow); out_offset += snprintf(buf + out_offset, out_count - out_offset, "rx_err_ver - \t%llu\n", qp->rx_err_ver); out_offset += snprintf(buf + out_offset, out_count - out_offset, "rx_buff - \t%p\n", qp->rx_buff); out_offset += snprintf(buf + out_offset, out_count - out_offset, "rx_index - \t%u\n", qp->rx_index); out_offset += snprintf(buf + out_offset, out_count - out_offset, "rx_max_entry - \t%u\n", qp->rx_max_entry); out_offset += snprintf(buf + out_offset, out_count - out_offset, "tx_bytes - \t%llu\n", qp->tx_bytes); out_offset += snprintf(buf + out_offset, out_count - out_offset, "tx_pkts - \t%llu\n", qp->tx_pkts); out_offset += snprintf(buf + out_offset, out_count - out_offset, "tx_memcpy - \t%llu\n", qp->tx_memcpy); out_offset += snprintf(buf + out_offset, out_count - out_offset, "tx_async - \t%llu\n", qp->tx_async); out_offset += snprintf(buf + out_offset, out_count - out_offset, "tx_ring_full - \t%llu\n", qp->tx_ring_full); out_offset += snprintf(buf + out_offset, out_count - out_offset, "tx_err_no_buf - %llu\n", qp->tx_err_no_buf); out_offset += snprintf(buf + out_offset, out_count - out_offset, "tx_mw - \t%p\n", qp->tx_mw); out_offset += snprintf(buf + out_offset, out_count - out_offset, "tx_index - \t%u\n", qp->tx_index); out_offset += snprintf(buf + out_offset, out_count - out_offset, "tx_max_entry - \t%u\n", qp->tx_max_entry); out_offset += snprintf(buf + out_offset, out_count - out_offset, "\nQP Link %s\n", (qp->qp_link == NTB_LINK_UP) ? "Up" : "Down"); if (out_offset > out_count) out_offset = out_count; ret = simple_read_from_buffer(ubuf, count, offp, buf, out_offset); kfree(buf); return ret; } static const struct file_operations ntb_qp_debugfs_stats = { .owner = THIS_MODULE, .open = simple_open, .read = debugfs_read, }; static void ntb_list_add(spinlock_t *lock, struct list_head *entry, struct list_head *list) { unsigned long flags; spin_lock_irqsave(lock, flags); list_add_tail(entry, list); spin_unlock_irqrestore(lock, flags); } static struct ntb_queue_entry *ntb_list_rm(spinlock_t *lock, struct list_head *list) { struct ntb_queue_entry *entry; unsigned long flags; spin_lock_irqsave(lock, flags); if (list_empty(list)) { entry = NULL; goto out; } entry = list_first_entry(list, struct ntb_queue_entry, entry); list_del(&entry->entry); out: spin_unlock_irqrestore(lock, flags); return entry; } static void ntb_transport_setup_qp_mw(struct ntb_transport *nt, unsigned int qp_num) { struct ntb_transport_qp *qp = &nt->qps[qp_num]; unsigned int rx_size, num_qps_mw; u8 mw_num, mw_max; unsigned int i; mw_max = ntb_max_mw(nt->ndev); mw_num = QP_TO_MW(nt->ndev, qp_num); WARN_ON(nt->mw[mw_num].virt_addr == NULL); if (nt->max_qps % mw_max && mw_num < nt->max_qps % mw_max) num_qps_mw = nt->max_qps / mw_max + 1; else num_qps_mw = nt->max_qps / mw_max; rx_size = (unsigned int) nt->mw[mw_num].size / num_qps_mw; qp->rx_buff = nt->mw[mw_num].virt_addr + qp_num / mw_max * rx_size; rx_size -= sizeof(struct ntb_rx_info); qp->remote_rx_info = qp->rx_buff + rx_size; /* Due to housekeeping, there must be atleast 2 buffs */ qp->rx_max_frame = min(transport_mtu, rx_size / 2); qp->rx_max_entry = rx_size / qp->rx_max_frame; qp->rx_index = 0; qp->remote_rx_info->entry = qp->rx_max_entry - 1; /* setup the hdr offsets with 0's */ for (i = 0; i < qp->rx_max_entry; i++) { void *offset = qp->rx_buff + qp->rx_max_frame * (i + 1) - sizeof(struct ntb_payload_header); memset(offset, 0, sizeof(struct ntb_payload_header)); } qp->rx_pkts = 0; qp->tx_pkts = 0; qp->tx_index = 0; } static void ntb_free_mw(struct ntb_transport *nt, int num_mw) { struct ntb_transport_mw *mw = &nt->mw[num_mw]; struct pci_dev *pdev = ntb_query_pdev(nt->ndev); if (!mw->virt_addr) return; dma_free_coherent(&pdev->dev, mw->size, mw->virt_addr, mw->dma_addr); mw->virt_addr = NULL; } static int ntb_set_mw(struct ntb_transport *nt, int num_mw, unsigned int size) { struct ntb_transport_mw *mw = &nt->mw[num_mw]; struct pci_dev *pdev = ntb_query_pdev(nt->ndev); /* No need to re-setup */ if (mw->size == ALIGN(size, 4096)) return 0; if (mw->size != 0) ntb_free_mw(nt, num_mw); /* Alloc memory for receiving data. Must be 4k aligned */ mw->size = ALIGN(size, 4096); mw->virt_addr = dma_alloc_coherent(&pdev->dev, mw->size, &mw->dma_addr, GFP_KERNEL); if (!mw->virt_addr) { mw->size = 0; dev_err(&pdev->dev, "Unable to allocate MW buffer of size %d\n", (int) mw->size); return -ENOMEM; } /* Notify HW the memory location of the receive buffer */ ntb_set_mw_addr(nt->ndev, num_mw, mw->dma_addr); return 0; } static void ntb_qp_link_cleanup(struct work_struct *work) { struct ntb_transport_qp *qp = container_of(work, struct ntb_transport_qp, link_cleanup); struct ntb_transport *nt = qp->transport; struct pci_dev *pdev = ntb_query_pdev(nt->ndev); if (qp->qp_link == NTB_LINK_DOWN) { cancel_delayed_work_sync(&qp->link_work); return; } if (qp->event_handler) qp->event_handler(qp->cb_data, NTB_LINK_DOWN); dev_info(&pdev->dev, "qp %d: Link Down\n", qp->qp_num); qp->qp_link = NTB_LINK_DOWN; if (nt->transport_link == NTB_LINK_UP) schedule_delayed_work(&qp->link_work, msecs_to_jiffies(NTB_LINK_DOWN_TIMEOUT)); } static void ntb_qp_link_down(struct ntb_transport_qp *qp) { schedule_work(&qp->link_cleanup); } static void ntb_transport_link_cleanup(struct work_struct *work) { struct ntb_transport *nt = container_of(work, struct ntb_transport, link_cleanup); int i; if (nt->transport_link == NTB_LINK_DOWN) cancel_delayed_work_sync(&nt->link_work); else nt->transport_link = NTB_LINK_DOWN; /* Pass along the info to any clients */ for (i = 0; i < nt->max_qps; i++) if (!test_bit(i, &nt->qp_bitmap)) ntb_qp_link_down(&nt->qps[i]); /* The scratchpad registers keep the values if the remote side * goes down, blast them now to give them a sane value the next * time they are accessed */ for (i = 0; i < MAX_SPAD; i++) ntb_write_local_spad(nt->ndev, i, 0); } static void ntb_transport_event_callback(void *data, enum ntb_hw_event event) { struct ntb_transport *nt = data; switch (event) { case NTB_EVENT_HW_LINK_UP: schedule_delayed_work(&nt->link_work, 0); break; case NTB_EVENT_HW_LINK_DOWN: schedule_work(&nt->link_cleanup); break; default: BUG(); } } static void ntb_transport_link_work(struct work_struct *work) { struct ntb_transport *nt = container_of(work, struct ntb_transport, link_work.work); struct ntb_device *ndev = nt->ndev; struct pci_dev *pdev = ntb_query_pdev(ndev); u32 val; int rc, i; /* send the local info, in the opposite order of the way we read it */ for (i = 0; i < ntb_max_mw(ndev); i++) { rc = ntb_write_remote_spad(ndev, MW0_SZ_HIGH + (i * 2), ntb_get_mw_size(ndev, i) >> 32); if (rc) { dev_err(&pdev->dev, "Error writing %u to remote spad %d\n", (u32)(ntb_get_mw_size(ndev, i) >> 32), MW0_SZ_HIGH + (i * 2)); goto out; } rc = ntb_write_remote_spad(ndev, MW0_SZ_LOW + (i * 2), (u32) ntb_get_mw_size(ndev, i)); if (rc) { dev_err(&pdev->dev, "Error writing %u to remote spad %d\n", (u32) ntb_get_mw_size(ndev, i), MW0_SZ_LOW + (i * 2)); goto out; } } rc = ntb_write_remote_spad(ndev, NUM_MWS, ntb_max_mw(ndev)); if (rc) { dev_err(&pdev->dev, "Error writing %x to remote spad %d\n", ntb_max_mw(ndev), NUM_MWS); goto out; } rc = ntb_write_remote_spad(ndev, NUM_QPS, nt->max_qps); if (rc) { dev_err(&pdev->dev, "Error writing %x to remote spad %d\n", nt->max_qps, NUM_QPS); goto out; } rc = ntb_write_remote_spad(ndev, VERSION, NTB_TRANSPORT_VERSION); if (rc) { dev_err(&pdev->dev, "Error writing %x to remote spad %d\n", NTB_TRANSPORT_VERSION, VERSION); goto out; } /* Query the remote side for its info */ rc = ntb_read_remote_spad(ndev, VERSION, &val); if (rc) { dev_err(&pdev->dev, "Error reading remote spad %d\n", VERSION); goto out; } if (val != NTB_TRANSPORT_VERSION) goto out; dev_dbg(&pdev->dev, "Remote version = %d\n", val); rc = ntb_read_remote_spad(ndev, NUM_QPS, &val); if (rc) { dev_err(&pdev->dev, "Error reading remote spad %d\n", NUM_QPS); goto out; } if (val != nt->max_qps) goto out; dev_dbg(&pdev->dev, "Remote max number of qps = %d\n", val); rc = ntb_read_remote_spad(ndev, NUM_MWS, &val); if (rc) { dev_err(&pdev->dev, "Error reading remote spad %d\n", NUM_MWS); goto out; } if (val != ntb_max_mw(ndev)) goto out; dev_dbg(&pdev->dev, "Remote number of mws = %d\n", val); for (i = 0; i < ntb_max_mw(ndev); i++) { u64 val64; rc = ntb_read_remote_spad(ndev, MW0_SZ_HIGH + (i * 2), &val); if (rc) { dev_err(&pdev->dev, "Error reading remote spad %d\n", MW0_SZ_HIGH + (i * 2)); goto out1; } val64 = (u64) val << 32; rc = ntb_read_remote_spad(ndev, MW0_SZ_LOW + (i * 2), &val); if (rc) { dev_err(&pdev->dev, "Error reading remote spad %d\n", MW0_SZ_LOW + (i * 2)); goto out1; } val64 |= val; dev_dbg(&pdev->dev, "Remote MW%d size = %llu\n", i, val64); rc = ntb_set_mw(nt, i, val64); if (rc) goto out1; } nt->transport_link = NTB_LINK_UP; for (i = 0; i < nt->max_qps; i++) { struct ntb_transport_qp *qp = &nt->qps[i]; ntb_transport_setup_qp_mw(nt, i); if (qp->client_ready == NTB_LINK_UP) schedule_delayed_work(&qp->link_work, 0); } return; out1: for (i = 0; i < ntb_max_mw(ndev); i++) ntb_free_mw(nt, i); out: if (ntb_hw_link_status(ndev)) schedule_delayed_work(&nt->link_work, msecs_to_jiffies(NTB_LINK_DOWN_TIMEOUT)); } static void ntb_qp_link_work(struct work_struct *work) { struct ntb_transport_qp *qp = container_of(work, struct ntb_transport_qp, link_work.work); struct pci_dev *pdev = ntb_query_pdev(qp->ndev); struct ntb_transport *nt = qp->transport; int rc, val; WARN_ON(nt->transport_link != NTB_LINK_UP); rc = ntb_read_local_spad(nt->ndev, QP_LINKS, &val); if (rc) { dev_err(&pdev->dev, "Error reading spad %d\n", QP_LINKS); return; } rc = ntb_write_remote_spad(nt->ndev, QP_LINKS, val | 1 << qp->qp_num); if (rc) dev_err(&pdev->dev, "Error writing %x to remote spad %d\n", val | 1 << qp->qp_num, QP_LINKS); /* query remote spad for qp ready bits */ rc = ntb_read_remote_spad(nt->ndev, QP_LINKS, &val); if (rc) dev_err(&pdev->dev, "Error reading remote spad %d\n", QP_LINKS); dev_dbg(&pdev->dev, "Remote QP link status = %x\n", val); /* See if the remote side is up */ if (1 << qp->qp_num & val) { qp->qp_link = NTB_LINK_UP; dev_info(&pdev->dev, "qp %d: Link Up\n", qp->qp_num); if (qp->event_handler) qp->event_handler(qp->cb_data, NTB_LINK_UP); } else if (nt->transport_link == NTB_LINK_UP) schedule_delayed_work(&qp->link_work, msecs_to_jiffies(NTB_LINK_DOWN_TIMEOUT)); } static int ntb_transport_init_queue(struct ntb_transport *nt, unsigned int qp_num) { struct ntb_transport_qp *qp; unsigned int num_qps_mw, tx_size; u8 mw_num, mw_max; u64 qp_offset; mw_max = ntb_max_mw(nt->ndev); mw_num = QP_TO_MW(nt->ndev, qp_num); qp = &nt->qps[qp_num]; qp->qp_num = qp_num; qp->transport = nt; qp->ndev = nt->ndev; qp->qp_link = NTB_LINK_DOWN; qp->client_ready = NTB_LINK_DOWN; qp->event_handler = NULL; if (nt->max_qps % mw_max && mw_num < nt->max_qps % mw_max) num_qps_mw = nt->max_qps / mw_max + 1; else num_qps_mw = nt->max_qps / mw_max; tx_size = (unsigned int) ntb_get_mw_size(qp->ndev, mw_num) / num_qps_mw; qp_offset = qp_num / mw_max * tx_size; qp->tx_mw = ntb_get_mw_vbase(nt->ndev, mw_num) + qp_offset; if (!qp->tx_mw) return -EINVAL; qp->tx_mw_phys = ntb_get_mw_base(qp->ndev, mw_num) + qp_offset; if (!qp->tx_mw_phys) return -EINVAL; tx_size -= sizeof(struct ntb_rx_info); qp->rx_info = qp->tx_mw + tx_size; /* Due to housekeeping, there must be atleast 2 buffs */ qp->tx_max_frame = min(transport_mtu, tx_size / 2); qp->tx_max_entry = tx_size / qp->tx_max_frame; if (ntb_query_debugfs(nt->ndev)) { char debugfs_name[4]; snprintf(debugfs_name, 4, "qp%d", qp_num); qp->debugfs_dir = debugfs_create_dir(debugfs_name, ntb_query_debugfs(nt->ndev)); qp->debugfs_stats = debugfs_create_file("stats", S_IRUSR, qp->debugfs_dir, qp, &ntb_qp_debugfs_stats); } INIT_DELAYED_WORK(&qp->link_work, ntb_qp_link_work); INIT_WORK(&qp->link_cleanup, ntb_qp_link_cleanup); spin_lock_init(&qp->ntb_rx_pend_q_lock); spin_lock_init(&qp->ntb_rx_free_q_lock); spin_lock_init(&qp->ntb_tx_free_q_lock); INIT_LIST_HEAD(&qp->rx_pend_q); INIT_LIST_HEAD(&qp->rx_free_q); INIT_LIST_HEAD(&qp->tx_free_q); return 0; } int ntb_transport_init(struct pci_dev *pdev) { struct ntb_transport *nt; int rc, i; nt = kzalloc(sizeof(struct ntb_transport), GFP_KERNEL); if (!nt) return -ENOMEM; nt->ndev = ntb_register_transport(pdev, nt); if (!nt->ndev) { rc = -EIO; goto err; } nt->mw = kcalloc(ntb_max_mw(nt->ndev), sizeof(struct ntb_transport_mw), GFP_KERNEL); if (!nt->mw) { rc = -ENOMEM; goto err1; } if (max_num_clients) nt->max_qps = min(ntb_max_cbs(nt->ndev), max_num_clients); else nt->max_qps = min(ntb_max_cbs(nt->ndev), ntb_max_mw(nt->ndev)); nt->qps = kcalloc(nt->max_qps, sizeof(struct ntb_transport_qp), GFP_KERNEL); if (!nt->qps) { rc = -ENOMEM; goto err2; } nt->qp_bitmap = ((u64) 1 << nt->max_qps) - 1; for (i = 0; i < nt->max_qps; i++) { rc = ntb_transport_init_queue(nt, i); if (rc) goto err3; } INIT_DELAYED_WORK(&nt->link_work, ntb_transport_link_work); INIT_WORK(&nt->link_cleanup, ntb_transport_link_cleanup); rc = ntb_register_event_callback(nt->ndev, ntb_transport_event_callback); if (rc) goto err3; INIT_LIST_HEAD(&nt->client_devs); rc = ntb_bus_init(nt); if (rc) goto err4; if (ntb_hw_link_status(nt->ndev)) schedule_delayed_work(&nt->link_work, 0); return 0; err4: ntb_unregister_event_callback(nt->ndev); err3: kfree(nt->qps); err2: kfree(nt->mw); err1: ntb_unregister_transport(nt->ndev); err: kfree(nt); return rc; } void ntb_transport_free(void *transport) { struct ntb_transport *nt = transport; struct ntb_device *ndev = nt->ndev; int i; nt->transport_link = NTB_LINK_DOWN; /* verify that all the qp's are freed */ for (i = 0; i < nt->max_qps; i++) { if (!test_bit(i, &nt->qp_bitmap)) ntb_transport_free_queue(&nt->qps[i]); debugfs_remove_recursive(nt->qps[i].debugfs_dir); } ntb_bus_remove(nt); cancel_delayed_work_sync(&nt->link_work); ntb_unregister_event_callback(ndev); for (i = 0; i < ntb_max_mw(ndev); i++) ntb_free_mw(nt, i); kfree(nt->qps); kfree(nt->mw); ntb_unregister_transport(ndev); kfree(nt); } static void ntb_rx_copy_callback(void *data) { struct ntb_queue_entry *entry = data; struct ntb_transport_qp *qp = entry->qp; void *cb_data = entry->cb_data; unsigned int len = entry->len; struct ntb_payload_header *hdr = entry->rx_hdr; /* Ensure that the data is fully copied out before clearing the flag */ wmb(); hdr->flags = 0; iowrite32(entry->index, &qp->rx_info->entry); ntb_list_add(&qp->ntb_rx_free_q_lock, &entry->entry, &qp->rx_free_q); if (qp->rx_handler && qp->client_ready == NTB_LINK_UP) qp->rx_handler(qp, qp->cb_data, cb_data, len); } static void ntb_memcpy_rx(struct ntb_queue_entry *entry, void *offset) { void *buf = entry->buf; size_t len = entry->len; memcpy(buf, offset, len); ntb_rx_copy_callback(entry); } static void ntb_async_rx(struct ntb_queue_entry *entry, void *offset, size_t len) { struct dma_async_tx_descriptor *txd; struct ntb_transport_qp *qp = entry->qp; struct dma_chan *chan = qp->dma_chan; struct dma_device *device; size_t pay_off, buff_off; dma_addr_t src, dest; dma_cookie_t cookie; void *buf = entry->buf; unsigned long flags; entry->len = len; if (!chan) goto err; if (len < copy_bytes) goto err1; device = chan->device; pay_off = (size_t) offset & ~PAGE_MASK; buff_off = (size_t) buf & ~PAGE_MASK; if (!is_dma_copy_aligned(device, pay_off, buff_off, len)) goto err1; dest = dma_map_single(device->dev, buf, len, DMA_FROM_DEVICE); if (dma_mapping_error(device->dev, dest)) goto err1; src = dma_map_single(device->dev, offset, len, DMA_TO_DEVICE); if (dma_mapping_error(device->dev, src)) goto err2; flags = DMA_COMPL_DEST_UNMAP_SINGLE | DMA_COMPL_SRC_UNMAP_SINGLE | DMA_PREP_INTERRUPT; txd = device->device_prep_dma_memcpy(chan, dest, src, len, flags); if (!txd) goto err3; txd->callback = ntb_rx_copy_callback; txd->callback_param = entry; cookie = dmaengine_submit(txd); if (dma_submit_error(cookie)) goto err3; qp->last_cookie = cookie; qp->rx_async++; return; err3: dma_unmap_single(device->dev, src, len, DMA_TO_DEVICE); err2: dma_unmap_single(device->dev, dest, len, DMA_FROM_DEVICE); err1: /* If the callbacks come out of order, the writing of the index to the * last completed will be out of order. This may result in the * receive stalling forever. */ dma_sync_wait(chan, qp->last_cookie); err: ntb_memcpy_rx(entry, offset); qp->rx_memcpy++; } static int ntb_process_rxc(struct ntb_transport_qp *qp) { struct ntb_payload_header *hdr; struct ntb_queue_entry *entry; void *offset; offset = qp->rx_buff + qp->rx_max_frame * qp->rx_index; hdr = offset + qp->rx_max_frame - sizeof(struct ntb_payload_header); entry = ntb_list_rm(&qp->ntb_rx_pend_q_lock, &qp->rx_pend_q); if (!entry) { dev_dbg(&ntb_query_pdev(qp->ndev)->dev, "no buffer - HDR ver %u, len %d, flags %x\n", hdr->ver, hdr->len, hdr->flags); qp->rx_err_no_buf++; return -ENOMEM; } if (!(hdr->flags & DESC_DONE_FLAG)) { ntb_list_add(&qp->ntb_rx_pend_q_lock, &entry->entry, &qp->rx_pend_q); qp->rx_ring_empty++; return -EAGAIN; } if (hdr->ver != (u32) qp->rx_pkts) { dev_dbg(&ntb_query_pdev(qp->ndev)->dev, "qp %d: version mismatch, expected %llu - got %u\n", qp->qp_num, qp->rx_pkts, hdr->ver); ntb_list_add(&qp->ntb_rx_pend_q_lock, &entry->entry, &qp->rx_pend_q); qp->rx_err_ver++; return -EIO; } if (hdr->flags & LINK_DOWN_FLAG) { ntb_qp_link_down(qp); goto err; } dev_dbg(&ntb_query_pdev(qp->ndev)->dev, "rx offset %u, ver %u - %d payload received, buf size %d\n", qp->rx_index, hdr->ver, hdr->len, entry->len); qp->rx_bytes += hdr->len; qp->rx_pkts++; if (hdr->len > entry->len) { qp->rx_err_oflow++; dev_dbg(&ntb_query_pdev(qp->ndev)->dev, "RX overflow! Wanted %d got %d\n", hdr->len, entry->len); goto err; } entry->index = qp->rx_index; entry->rx_hdr = hdr; ntb_async_rx(entry, offset, hdr->len); out: qp->rx_index++; qp->rx_index %= qp->rx_max_entry; return 0; err: ntb_list_add(&qp->ntb_rx_pend_q_lock, &entry->entry, &qp->rx_pend_q); /* Ensure that the data is fully copied out before clearing the flag */ wmb(); hdr->flags = 0; iowrite32(qp->rx_index, &qp->rx_info->entry); goto out; } static void ntb_transport_rx(unsigned long data) { struct ntb_transport_qp *qp = (struct ntb_transport_qp *)data; int rc, i; /* Limit the number of packets processed in a single interrupt to * provide fairness to others */ for (i = 0; i < qp->rx_max_entry; i++) { rc = ntb_process_rxc(qp); if (rc) break; } if (qp->dma_chan) dma_async_issue_pending(qp->dma_chan); } static void ntb_transport_rxc_db(void *data, int db_num) { struct ntb_transport_qp *qp = data; dev_dbg(&ntb_query_pdev(qp->ndev)->dev, "%s: doorbell %d received\n", __func__, db_num); tasklet_schedule(&qp->rx_work); } static void ntb_tx_copy_callback(void *data) { struct ntb_queue_entry *entry = data; struct ntb_transport_qp *qp = entry->qp; struct ntb_payload_header __iomem *hdr = entry->tx_hdr; /* Ensure that the data is fully copied out before setting the flags */ wmb(); iowrite32(entry->flags | DESC_DONE_FLAG, &hdr->flags); ntb_ring_doorbell(qp->ndev, qp->qp_num); /* The entry length can only be zero if the packet is intended to be a * "link down" or similar. Since no payload is being sent in these * cases, there is nothing to add to the completion queue. */ if (entry->len > 0) { qp->tx_bytes += entry->len; if (qp->tx_handler) qp->tx_handler(qp, qp->cb_data, entry->cb_data, entry->len); } ntb_list_add(&qp->ntb_tx_free_q_lock, &entry->entry, &qp->tx_free_q); } static void ntb_memcpy_tx(struct ntb_queue_entry *entry, void __iomem *offset) { memcpy_toio(offset, entry->buf, entry->len); ntb_tx_copy_callback(entry); } static void ntb_async_tx(struct ntb_transport_qp *qp, struct ntb_queue_entry *entry) { struct ntb_payload_header __iomem *hdr; struct dma_async_tx_descriptor *txd; struct dma_chan *chan = qp->dma_chan; struct dma_device *device; size_t dest_off, buff_off; dma_addr_t src, dest; dma_cookie_t cookie; void __iomem *offset; size_t len = entry->len; void *buf = entry->buf; unsigned long flags; offset = qp->tx_mw + qp->tx_max_frame * qp->tx_index; hdr = offset + qp->tx_max_frame - sizeof(struct ntb_payload_header); entry->tx_hdr = hdr; iowrite32(entry->len, &hdr->len); iowrite32((u32) qp->tx_pkts, &hdr->ver); if (!chan) goto err; if (len < copy_bytes) goto err; device = chan->device; dest = qp->tx_mw_phys + qp->tx_max_frame * qp->tx_index; buff_off = (size_t) buf & ~PAGE_MASK; dest_off = (size_t) dest & ~PAGE_MASK; if (!is_dma_copy_aligned(device, buff_off, dest_off, len)) goto err; src = dma_map_single(device->dev, buf, len, DMA_TO_DEVICE); if (dma_mapping_error(device->dev, src)) goto err; flags = DMA_COMPL_SRC_UNMAP_SINGLE | DMA_PREP_INTERRUPT; txd = device->device_prep_dma_memcpy(chan, dest, src, len, flags); if (!txd) goto err1; txd->callback = ntb_tx_copy_callback; txd->callback_param = entry; cookie = dmaengine_submit(txd); if (dma_submit_error(cookie)) goto err1; dma_async_issue_pending(chan); qp->tx_async++; return; err1: dma_unmap_single(device->dev, src, len, DMA_TO_DEVICE); err: ntb_memcpy_tx(entry, offset); qp->tx_memcpy++; } static int ntb_process_tx(struct ntb_transport_qp *qp, struct ntb_queue_entry *entry) { dev_dbg(&ntb_query_pdev(qp->ndev)->dev, "%lld - tx %u, entry len %d flags %x buff %p\n", qp->tx_pkts, qp->tx_index, entry->len, entry->flags, entry->buf); if (qp->tx_index == qp->remote_rx_info->entry) { qp->tx_ring_full++; return -EAGAIN; } if (entry->len > qp->tx_max_frame - sizeof(struct ntb_payload_header)) { if (qp->tx_handler) qp->tx_handler(qp->cb_data, qp, NULL, -EIO); ntb_list_add(&qp->ntb_tx_free_q_lock, &entry->entry, &qp->tx_free_q); return 0; } ntb_async_tx(qp, entry); qp->tx_index++; qp->tx_index %= qp->tx_max_entry; qp->tx_pkts++; return 0; } static void ntb_send_link_down(struct ntb_transport_qp *qp) { struct pci_dev *pdev = ntb_query_pdev(qp->ndev); struct ntb_queue_entry *entry; int i, rc; if (qp->qp_link == NTB_LINK_DOWN) return; qp->qp_link = NTB_LINK_DOWN; dev_info(&pdev->dev, "qp %d: Link Down\n", qp->qp_num); for (i = 0; i < NTB_LINK_DOWN_TIMEOUT; i++) { entry = ntb_list_rm(&qp->ntb_tx_free_q_lock, &qp->tx_free_q); if (entry) break; msleep(100); } if (!entry) return; entry->cb_data = NULL; entry->buf = NULL; entry->len = 0; entry->flags = LINK_DOWN_FLAG; rc = ntb_process_tx(qp, entry); if (rc) dev_err(&pdev->dev, "ntb: QP%d unable to send linkdown msg\n", qp->qp_num); } /** * ntb_transport_create_queue - Create a new NTB transport layer queue * @rx_handler: receive callback function * @tx_handler: transmit callback function * @event_handler: event callback function * * Create a new NTB transport layer queue and provide the queue with a callback * routine for both transmit and receive. The receive callback routine will be * used to pass up data when the transport has received it on the queue. The * transmit callback routine will be called when the transport has completed the * transmission of the data on the queue and the data is ready to be freed. * * RETURNS: pointer to newly created ntb_queue, NULL on error. */ struct ntb_transport_qp * ntb_transport_create_queue(void *data, struct pci_dev *pdev, const struct ntb_queue_handlers *handlers) { struct ntb_queue_entry *entry; struct ntb_transport_qp *qp; struct ntb_transport *nt; unsigned int free_queue; int rc, i; nt = ntb_find_transport(pdev); if (!nt) goto err; free_queue = ffs(nt->qp_bitmap); if (!free_queue) goto err; /* decrement free_queue to make it zero based */ free_queue--; clear_bit(free_queue, &nt->qp_bitmap); qp = &nt->qps[free_queue]; qp->cb_data = data; qp->rx_handler = handlers->rx_handler; qp->tx_handler = handlers->tx_handler; qp->event_handler = handlers->event_handler; qp->dma_chan = dma_find_channel(DMA_MEMCPY); if (!qp->dma_chan) dev_info(&pdev->dev, "Unable to allocate DMA channel, using CPU instead\n"); else dmaengine_get(); for (i = 0; i < NTB_QP_DEF_NUM_ENTRIES; i++) { entry = kzalloc(sizeof(struct ntb_queue_entry), GFP_ATOMIC); if (!entry) goto err1; entry->qp = qp; ntb_list_add(&qp->ntb_rx_free_q_lock, &entry->entry, &qp->rx_free_q); } for (i = 0; i < NTB_QP_DEF_NUM_ENTRIES; i++) { entry = kzalloc(sizeof(struct ntb_queue_entry), GFP_ATOMIC); if (!entry) goto err2; entry->qp = qp; ntb_list_add(&qp->ntb_tx_free_q_lock, &entry->entry, &qp->tx_free_q); } tasklet_init(&qp->rx_work, ntb_transport_rx, (unsigned long) qp); rc = ntb_register_db_callback(qp->ndev, free_queue, qp, ntb_transport_rxc_db); if (rc) goto err3; dev_info(&pdev->dev, "NTB Transport QP %d created\n", qp->qp_num); return qp; err3: tasklet_disable(&qp->rx_work); err2: while ((entry = ntb_list_rm(&qp->ntb_tx_free_q_lock, &qp->tx_free_q))) kfree(entry); err1: while ((entry = ntb_list_rm(&qp->ntb_rx_free_q_lock, &qp->rx_free_q))) kfree(entry); set_bit(free_queue, &nt->qp_bitmap); err: return NULL; } EXPORT_SYMBOL_GPL(ntb_transport_create_queue); /** * ntb_transport_free_queue - Frees NTB transport queue * @qp: NTB queue to be freed * * Frees NTB transport queue */ void ntb_transport_free_queue(struct ntb_transport_qp *qp) { struct pci_dev *pdev; struct ntb_queue_entry *entry; if (!qp) return; pdev = ntb_query_pdev(qp->ndev); if (qp->dma_chan) { struct dma_chan *chan = qp->dma_chan; /* Putting the dma_chan to NULL will force any new traffic to be * processed by the CPU instead of the DAM engine */ qp->dma_chan = NULL; /* Try to be nice and wait for any queued DMA engine * transactions to process before smashing it with a rock */ dma_sync_wait(chan, qp->last_cookie); dmaengine_terminate_all(chan); dmaengine_put(); } ntb_unregister_db_callback(qp->ndev, qp->qp_num); tasklet_disable(&qp->rx_work); cancel_delayed_work_sync(&qp->link_work); while ((entry = ntb_list_rm(&qp->ntb_rx_free_q_lock, &qp->rx_free_q))) kfree(entry); while ((entry = ntb_list_rm(&qp->ntb_rx_pend_q_lock, &qp->rx_pend_q))) { dev_warn(&pdev->dev, "Freeing item from a non-empty queue\n"); kfree(entry); } while ((entry = ntb_list_rm(&qp->ntb_tx_free_q_lock, &qp->tx_free_q))) kfree(entry); set_bit(qp->qp_num, &qp->transport->qp_bitmap); dev_info(&pdev->dev, "NTB Transport QP %d freed\n", qp->qp_num); } EXPORT_SYMBOL_GPL(ntb_transport_free_queue); /** * ntb_transport_rx_remove - Dequeues enqueued rx packet * @qp: NTB queue to be freed * @len: pointer to variable to write enqueued buffers length * * Dequeues unused buffers from receive queue. Should only be used during * shutdown of qp. * * RETURNS: NULL error value on error, or void* for success. */ void *ntb_transport_rx_remove(struct ntb_transport_qp *qp, unsigned int *len) { struct ntb_queue_entry *entry; void *buf; if (!qp || qp->client_ready == NTB_LINK_UP) return NULL; entry = ntb_list_rm(&qp->ntb_rx_pend_q_lock, &qp->rx_pend_q); if (!entry) return NULL; buf = entry->cb_data; *len = entry->len; ntb_list_add(&qp->ntb_rx_free_q_lock, &entry->entry, &qp->rx_free_q); return buf; } EXPORT_SYMBOL_GPL(ntb_transport_rx_remove); /** * ntb_transport_rx_enqueue - Enqueue a new NTB queue entry * @qp: NTB transport layer queue the entry is to be enqueued on * @cb: per buffer pointer for callback function to use * @data: pointer to data buffer that incoming packets will be copied into * @len: length of the data buffer * * Enqueue a new receive buffer onto the transport queue into which a NTB * payload can be received into. * * RETURNS: An appropriate -ERRNO error value on error, or zero for success. */ int ntb_transport_rx_enqueue(struct ntb_transport_qp *qp, void *cb, void *data, unsigned int len) { struct ntb_queue_entry *entry; if (!qp) return -EINVAL; entry = ntb_list_rm(&qp->ntb_rx_free_q_lock, &qp->rx_free_q); if (!entry) return -ENOMEM; entry->cb_data = cb; entry->buf = data; entry->len = len; ntb_list_add(&qp->ntb_rx_pend_q_lock, &entry->entry, &qp->rx_pend_q); return 0; } EXPORT_SYMBOL_GPL(ntb_transport_rx_enqueue); /** * ntb_transport_tx_enqueue - Enqueue a new NTB queue entry * @qp: NTB transport layer queue the entry is to be enqueued on * @cb: per buffer pointer for callback function to use * @data: pointer to data buffer that will be sent * @len: length of the data buffer * * Enqueue a new transmit buffer onto the transport queue from which a NTB * payload will be transmitted. This assumes that a lock is behing held to * serialize access to the qp. * * RETURNS: An appropriate -ERRNO error value on error, or zero for success. */ int ntb_transport_tx_enqueue(struct ntb_transport_qp *qp, void *cb, void *data, unsigned int len) { struct ntb_queue_entry *entry; int rc; if (!qp || qp->qp_link != NTB_LINK_UP || !len) return -EINVAL; entry = ntb_list_rm(&qp->ntb_tx_free_q_lock, &qp->tx_free_q); if (!entry) { qp->tx_err_no_buf++; return -ENOMEM; } entry->cb_data = cb; entry->buf = data; entry->len = len; entry->flags = 0; rc = ntb_process_tx(qp, entry); if (rc) ntb_list_add(&qp->ntb_tx_free_q_lock, &entry->entry, &qp->tx_free_q); return rc; } EXPORT_SYMBOL_GPL(ntb_transport_tx_enqueue); /** * ntb_transport_link_up - Notify NTB transport of client readiness to use queue * @qp: NTB transport layer queue to be enabled * * Notify NTB transport layer of client readiness to use queue */ void ntb_transport_link_up(struct ntb_transport_qp *qp) { if (!qp) return; qp->client_ready = NTB_LINK_UP; if (qp->transport->transport_link == NTB_LINK_UP) schedule_delayed_work(&qp->link_work, 0); } EXPORT_SYMBOL_GPL(ntb_transport_link_up); /** * ntb_transport_link_down - Notify NTB transport to no longer enqueue data * @qp: NTB transport layer queue to be disabled * * Notify NTB transport layer of client's desire to no longer receive data on * transport queue specified. It is the client's responsibility to ensure all * entries on queue are purged or otherwise handled appropraitely. */ void ntb_transport_link_down(struct ntb_transport_qp *qp) { struct pci_dev *pdev; int rc, val; if (!qp) return; pdev = ntb_query_pdev(qp->ndev); qp->client_ready = NTB_LINK_DOWN; rc = ntb_read_local_spad(qp->ndev, QP_LINKS, &val); if (rc) { dev_err(&pdev->dev, "Error reading spad %d\n", QP_LINKS); return; } rc = ntb_write_remote_spad(qp->ndev, QP_LINKS, val & ~(1 << qp->qp_num)); if (rc) dev_err(&pdev->dev, "Error writing %x to remote spad %d\n", val & ~(1 << qp->qp_num), QP_LINKS); if (qp->qp_link == NTB_LINK_UP) ntb_send_link_down(qp); else cancel_delayed_work_sync(&qp->link_work); } EXPORT_SYMBOL_GPL(ntb_transport_link_down); /** * ntb_transport_link_query - Query transport link state * @qp: NTB transport layer queue to be queried * * Query connectivity to the remote system of the NTB transport queue * * RETURNS: true for link up or false for link down */ bool ntb_transport_link_query(struct ntb_transport_qp *qp) { if (!qp) return false; return qp->qp_link == NTB_LINK_UP; } EXPORT_SYMBOL_GPL(ntb_transport_link_query); /** * ntb_transport_qp_num - Query the qp number * @qp: NTB transport layer queue to be queried * * Query qp number of the NTB transport queue * * RETURNS: a zero based number specifying the qp number */ unsigned char ntb_transport_qp_num(struct ntb_transport_qp *qp) { if (!qp) return 0; return qp->qp_num; } EXPORT_SYMBOL_GPL(ntb_transport_qp_num); /** * ntb_transport_max_size - Query the max payload size of a qp * @qp: NTB transport layer queue to be queried * * Query the maximum payload size permissible on the given qp * * RETURNS: the max payload size of a qp */ unsigned int ntb_transport_max_size(struct ntb_transport_qp *qp) { unsigned int max; if (!qp) return 0; if (!qp->dma_chan) return qp->tx_max_frame - sizeof(struct ntb_payload_header); /* If DMA engine usage is possible, try to find the max size for that */ max = qp->tx_max_frame - sizeof(struct ntb_payload_header); max -= max % (1 << qp->dma_chan->device->copy_align); return max; } EXPORT_SYMBOL_GPL(ntb_transport_max_size);