diff options
-rw-r--r-- | net/rds/iw.c | 333 | ||||
-rw-r--r-- | net/rds/iw.h | 395 | ||||
-rw-r--r-- | net/rds/iw_cm.c | 750 | ||||
-rw-r--r-- | net/rds/iw_rdma.c | 888 | ||||
-rw-r--r-- | net/rds/iw_recv.c | 869 | ||||
-rw-r--r-- | net/rds/iw_ring.c | 169 | ||||
-rw-r--r-- | net/rds/iw_send.c | 975 | ||||
-rw-r--r-- | net/rds/iw_stats.c | 95 | ||||
-rw-r--r-- | net/rds/iw_sysctl.c | 137 |
9 files changed, 4611 insertions, 0 deletions
diff --git a/net/rds/iw.c b/net/rds/iw.c new file mode 100644 index 0000000..1b56905 --- /dev/null +++ b/net/rds/iw.c @@ -0,0 +1,333 @@ +/* + * Copyright (c) 2006 Oracle. All rights reserved. + * + * This software is available to you under a choice of one of two + * licenses. You may choose to be licensed under the terms of the GNU + * General Public License (GPL) Version 2, available from the file + * COPYING in the main directory of this source tree, or the + * OpenIB.org BSD license below: + * + * 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 + * copyright notice, this list of conditions and the following + * disclaimer in the documentation and/or other materials + * provided with the distribution. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + * + */ +#include <linux/kernel.h> +#include <linux/in.h> +#include <linux/if.h> +#include <linux/netdevice.h> +#include <linux/inetdevice.h> +#include <linux/if_arp.h> +#include <linux/delay.h> + +#include "rds.h" +#include "iw.h" + +unsigned int fastreg_pool_size = RDS_FASTREG_POOL_SIZE; +unsigned int fastreg_message_size = RDS_FASTREG_SIZE + 1; /* +1 allows for unaligned MRs */ + +module_param(fastreg_pool_size, int, 0444); +MODULE_PARM_DESC(fastreg_pool_size, " Max number of fastreg MRs per device"); +module_param(fastreg_message_size, int, 0444); +MODULE_PARM_DESC(fastreg_message_size, " Max size of a RDMA transfer (fastreg MRs)"); + +struct list_head rds_iw_devices; + +DEFINE_SPINLOCK(iw_nodev_conns_lock); +LIST_HEAD(iw_nodev_conns); + +void rds_iw_add_one(struct ib_device *device) +{ + struct rds_iw_device *rds_iwdev; + struct ib_device_attr *dev_attr; + + /* Only handle iwarp devices */ + if (device->node_type != RDMA_NODE_RNIC) + return; + + dev_attr = kmalloc(sizeof *dev_attr, GFP_KERNEL); + if (!dev_attr) + return; + + if (ib_query_device(device, dev_attr)) { + rdsdebug("Query device failed for %s\n", device->name); + goto free_attr; + } + + rds_iwdev = kmalloc(sizeof *rds_iwdev, GFP_KERNEL); + if (!rds_iwdev) + goto free_attr; + + spin_lock_init(&rds_iwdev->spinlock); + + rds_iwdev->dma_local_lkey = !!(dev_attr->device_cap_flags & IB_DEVICE_LOCAL_DMA_LKEY); + rds_iwdev->max_wrs = dev_attr->max_qp_wr; + rds_iwdev->max_sge = min(dev_attr->max_sge, RDS_IW_MAX_SGE); + + rds_iwdev->page_shift = max(PAGE_SHIFT, ffs(dev_attr->page_size_cap) - 1); + + rds_iwdev->dev = device; + rds_iwdev->pd = ib_alloc_pd(device); + if (IS_ERR(rds_iwdev->pd)) + goto free_dev; + + if (!rds_iwdev->dma_local_lkey) { + if (device->node_type != RDMA_NODE_RNIC) { + rds_iwdev->mr = ib_get_dma_mr(rds_iwdev->pd, + IB_ACCESS_LOCAL_WRITE); + } else { + rds_iwdev->mr = ib_get_dma_mr(rds_iwdev->pd, + IB_ACCESS_REMOTE_READ | + IB_ACCESS_REMOTE_WRITE | + IB_ACCESS_LOCAL_WRITE); + } + if (IS_ERR(rds_iwdev->mr)) + goto err_pd; + } else + rds_iwdev->mr = NULL; + + rds_iwdev->mr_pool = rds_iw_create_mr_pool(rds_iwdev); + if (IS_ERR(rds_iwdev->mr_pool)) { + rds_iwdev->mr_pool = NULL; + goto err_mr; + } + + INIT_LIST_HEAD(&rds_iwdev->cm_id_list); + INIT_LIST_HEAD(&rds_iwdev->conn_list); + list_add_tail(&rds_iwdev->list, &rds_iw_devices); + + ib_set_client_data(device, &rds_iw_client, rds_iwdev); + + goto free_attr; + +err_mr: + if (rds_iwdev->mr) + ib_dereg_mr(rds_iwdev->mr); +err_pd: + ib_dealloc_pd(rds_iwdev->pd); +free_dev: + kfree(rds_iwdev); +free_attr: + kfree(dev_attr); +} + +void rds_iw_remove_one(struct ib_device *device) +{ + struct rds_iw_device *rds_iwdev; + struct rds_iw_cm_id *i_cm_id, *next; + + rds_iwdev = ib_get_client_data(device, &rds_iw_client); + if (!rds_iwdev) + return; + + spin_lock_irq(&rds_iwdev->spinlock); + list_for_each_entry_safe(i_cm_id, next, &rds_iwdev->cm_id_list, list) { + list_del(&i_cm_id->list); + kfree(i_cm_id); + } + spin_unlock_irq(&rds_iwdev->spinlock); + + rds_iw_remove_conns(rds_iwdev); + + if (rds_iwdev->mr_pool) + rds_iw_destroy_mr_pool(rds_iwdev->mr_pool); + + if (rds_iwdev->mr) + ib_dereg_mr(rds_iwdev->mr); + + while (ib_dealloc_pd(rds_iwdev->pd)) { + rdsdebug("Failed to dealloc pd %p\n", rds_iwdev->pd); + msleep(1); + } + + list_del(&rds_iwdev->list); + kfree(rds_iwdev); +} + +struct ib_client rds_iw_client = { + .name = "rds_iw", + .add = rds_iw_add_one, + .remove = rds_iw_remove_one +}; + +static int rds_iw_conn_info_visitor(struct rds_connection *conn, + void *buffer) +{ + struct rds_info_rdma_connection *iinfo = buffer; + struct rds_iw_connection *ic; + + /* We will only ever look at IB transports */ + if (conn->c_trans != &rds_iw_transport) + return 0; + + iinfo->src_addr = conn->c_laddr; + iinfo->dst_addr = conn->c_faddr; + + memset(&iinfo->src_gid, 0, sizeof(iinfo->src_gid)); + memset(&iinfo->dst_gid, 0, sizeof(iinfo->dst_gid)); + if (rds_conn_state(conn) == RDS_CONN_UP) { + struct rds_iw_device *rds_iwdev; + struct rdma_dev_addr *dev_addr; + + ic = conn->c_transport_data; + dev_addr = &ic->i_cm_id->route.addr.dev_addr; + + ib_addr_get_sgid(dev_addr, (union ib_gid *) &iinfo->src_gid); + ib_addr_get_dgid(dev_addr, (union ib_gid *) &iinfo->dst_gid); + + rds_iwdev = ib_get_client_data(ic->i_cm_id->device, &rds_iw_client); + iinfo->max_send_wr = ic->i_send_ring.w_nr; + iinfo->max_recv_wr = ic->i_recv_ring.w_nr; + iinfo->max_send_sge = rds_iwdev->max_sge; + rds_iw_get_mr_info(rds_iwdev, iinfo); + } + return 1; +} + +static void rds_iw_ic_info(struct socket *sock, unsigned int len, + struct rds_info_iterator *iter, + struct rds_info_lengths *lens) +{ + rds_for_each_conn_info(sock, len, iter, lens, + rds_iw_conn_info_visitor, + sizeof(struct rds_info_rdma_connection)); +} + + +/* + * Early RDS/IB was built to only bind to an address if there is an IPoIB + * device with that address set. + * + * If it were me, I'd advocate for something more flexible. Sending and + * receiving should be device-agnostic. Transports would try and maintain + * connections between peers who have messages queued. Userspace would be + * allowed to influence which paths have priority. We could call userspace + * asserting this policy "routing". + */ +static int rds_iw_laddr_check(__be32 addr) +{ + int ret; + struct rdma_cm_id *cm_id; + struct sockaddr_in sin; + + /* Create a CMA ID and try to bind it. This catches both + * IB and iWARP capable NICs. + */ + cm_id = rdma_create_id(NULL, NULL, RDMA_PS_TCP); + if (!cm_id) + return -EADDRNOTAVAIL; + + memset(&sin, 0, sizeof(sin)); + sin.sin_family = AF_INET; + sin.sin_addr.s_addr = addr; + + /* rdma_bind_addr will only succeed for IB & iWARP devices */ + ret = rdma_bind_addr(cm_id, (struct sockaddr *)&sin); + /* due to this, we will claim to support IB devices unless we + check node_type. */ + if (ret || cm_id->device->node_type != RDMA_NODE_RNIC) + ret = -EADDRNOTAVAIL; + + rdsdebug("addr %pI4 ret %d node type %d\n", + &addr, ret, + cm_id->device ? cm_id->device->node_type : -1); + + rdma_destroy_id(cm_id); + + return ret; +} + +void rds_iw_exit(void) +{ + rds_info_deregister_func(RDS_INFO_IWARP_CONNECTIONS, rds_iw_ic_info); + rds_iw_remove_nodev_conns(); + ib_unregister_client(&rds_iw_client); + rds_iw_sysctl_exit(); + rds_iw_recv_exit(); + rds_trans_unregister(&rds_iw_transport); +} + +struct rds_transport rds_iw_transport = { + .laddr_check = rds_iw_laddr_check, + .xmit_complete = rds_iw_xmit_complete, + .xmit = rds_iw_xmit, + .xmit_cong_map = NULL, + .xmit_rdma = rds_iw_xmit_rdma, + .recv = rds_iw_recv, + .conn_alloc = rds_iw_conn_alloc, + .conn_free = rds_iw_conn_free, + .conn_connect = rds_iw_conn_connect, + .conn_shutdown = rds_iw_conn_shutdown, + .inc_copy_to_user = rds_iw_inc_copy_to_user, + .inc_purge = rds_iw_inc_purge, + .inc_free = rds_iw_inc_free, + .cm_initiate_connect = rds_iw_cm_initiate_connect, + .cm_handle_connect = rds_iw_cm_handle_connect, + .cm_connect_complete = rds_iw_cm_connect_complete, + .stats_info_copy = rds_iw_stats_info_copy, + .exit = rds_iw_exit, + .get_mr = rds_iw_get_mr, + .sync_mr = rds_iw_sync_mr, + .free_mr = rds_iw_free_mr, + .flush_mrs = rds_iw_flush_mrs, + .t_owner = THIS_MODULE, + .t_name = "iwarp", + .t_prefer_loopback = 1, +}; + +int __init rds_iw_init(void) +{ + int ret; + + INIT_LIST_HEAD(&rds_iw_devices); + + ret = ib_register_client(&rds_iw_client); + if (ret) + goto out; + + ret = rds_iw_sysctl_init(); + if (ret) + goto out_ibreg; + + ret = rds_iw_recv_init(); + if (ret) + goto out_sysctl; + + ret = rds_trans_register(&rds_iw_transport); + if (ret) + goto out_recv; + + rds_info_register_func(RDS_INFO_IWARP_CONNECTIONS, rds_iw_ic_info); + + goto out; + +out_recv: + rds_iw_recv_exit(); +out_sysctl: + rds_iw_sysctl_exit(); +out_ibreg: + ib_unregister_client(&rds_iw_client); +out: + return ret; +} + +MODULE_LICENSE("GPL"); + diff --git a/net/rds/iw.h b/net/rds/iw.h new file mode 100644 index 0000000..0ddda34 --- /dev/null +++ b/net/rds/iw.h @@ -0,0 +1,395 @@ +#ifndef _RDS_IW_H +#define _RDS_IW_H + +#include <rdma/ib_verbs.h> +#include <rdma/rdma_cm.h> +#include "rds.h" +#include "rdma_transport.h" + +#define RDS_FASTREG_SIZE 20 +#define RDS_FASTREG_POOL_SIZE 2048 + +#define RDS_IW_MAX_SGE 8 +#define RDS_IW_RECV_SGE 2 + +#define RDS_IW_DEFAULT_RECV_WR 1024 +#define RDS_IW_DEFAULT_SEND_WR 256 + +#define RDS_IW_SUPPORTED_PROTOCOLS 0x00000003 /* minor versions supported */ + +extern struct list_head rds_iw_devices; + +/* + * IB posts RDS_FRAG_SIZE fragments of pages to the receive queues to + * try and minimize the amount of memory tied up both the device and + * socket receive queues. + */ +/* page offset of the final full frag that fits in the page */ +#define RDS_PAGE_LAST_OFF (((PAGE_SIZE / RDS_FRAG_SIZE) - 1) * RDS_FRAG_SIZE) +struct rds_page_frag { + struct list_head f_item; + struct page *f_page; + unsigned long f_offset; + dma_addr_t f_mapped; +}; + +struct rds_iw_incoming { + struct list_head ii_frags; + struct rds_incoming ii_inc; +}; + +struct rds_iw_connect_private { + /* Add new fields at the end, and don't permute existing fields. */ + __be32 dp_saddr; + __be32 dp_daddr; + u8 dp_protocol_major; + u8 dp_protocol_minor; + __be16 dp_protocol_minor_mask; /* bitmask */ + __be32 dp_reserved1; + __be64 dp_ack_seq; + __be32 dp_credit; /* non-zero enables flow ctl */ +}; + +struct rds_iw_scatterlist { + struct scatterlist *list; + unsigned int len; + int dma_len; + unsigned int dma_npages; + unsigned int bytes; +}; + +struct rds_iw_mapping { + spinlock_t m_lock; /* protect the mapping struct */ + struct list_head m_list; + struct rds_iw_mr *m_mr; + uint32_t m_rkey; + struct rds_iw_scatterlist m_sg; +}; + +struct rds_iw_send_work { + struct rds_message *s_rm; + + /* We should really put these into a union: */ + struct rds_rdma_op *s_op; + struct rds_iw_mapping *s_mapping; + struct ib_mr *s_mr; + struct ib_fast_reg_page_list *s_page_list; + unsigned char s_remap_count; + + struct ib_send_wr s_wr; + struct ib_sge s_sge[RDS_IW_MAX_SGE]; + unsigned long s_queued; +}; + +struct rds_iw_recv_work { + struct rds_iw_incoming *r_iwinc; + struct rds_page_frag *r_frag; + struct ib_recv_wr r_wr; + struct ib_sge r_sge[2]; +}; + +struct rds_iw_work_ring { + u32 w_nr; + u32 w_alloc_ptr; + u32 w_alloc_ctr; + u32 w_free_ptr; + atomic_t w_free_ctr; +}; + +struct rds_iw_device; + +struct rds_iw_connection { + + struct list_head iw_node; + struct rds_iw_device *rds_iwdev; + struct rds_connection *conn; + + /* alphabet soup, IBTA style */ + struct rdma_cm_id *i_cm_id; + struct ib_pd *i_pd; + struct ib_mr *i_mr; + struct ib_cq *i_send_cq; + struct ib_cq *i_recv_cq; + + /* tx */ + struct rds_iw_work_ring i_send_ring; + struct rds_message *i_rm; + struct rds_header *i_send_hdrs; + u64 i_send_hdrs_dma; + struct rds_iw_send_work *i_sends; + + /* rx */ + struct mutex i_recv_mutex; + struct rds_iw_work_ring i_recv_ring; + struct rds_iw_incoming *i_iwinc; + u32 i_recv_data_rem; + struct rds_header *i_recv_hdrs; + u64 i_recv_hdrs_dma; + struct rds_iw_recv_work *i_recvs; + struct rds_page_frag i_frag; + u64 i_ack_recv; /* last ACK received */ + + /* sending acks */ + unsigned long i_ack_flags; + u64 i_ack_next; /* next ACK to send */ + struct rds_header *i_ack; + struct ib_send_wr i_ack_wr; + struct ib_sge i_ack_sge; + u64 i_ack_dma; + unsigned long i_ack_queued; + + /* Flow control related information + * + * Our algorithm uses a pair variables that we need to access + * atomically - one for the send credits, and one posted + * recv credits we need to transfer to remote. + * Rather than protect them using a slow spinlock, we put both into + * a single atomic_t and update it using cmpxchg + */ + atomic_t i_credits; + + /* Protocol version specific information */ + unsigned int i_flowctl:1; /* enable/disable flow ctl */ + unsigned int i_dma_local_lkey:1; + unsigned int i_fastreg_posted:1; /* fastreg posted on this connection */ + /* Batched completions */ + unsigned int i_unsignaled_wrs; + long i_unsignaled_bytes; +}; + +/* This assumes that atomic_t is at least 32 bits */ +#define IB_GET_SEND_CREDITS(v) ((v) & 0xffff) +#define IB_GET_POST_CREDITS(v) ((v) >> 16) +#define IB_SET_SEND_CREDITS(v) ((v) & 0xffff) +#define IB_SET_POST_CREDITS(v) ((v) << 16) + +struct rds_iw_cm_id { + struct list_head list; + struct rdma_cm_id *cm_id; +}; + +struct rds_iw_device { + struct list_head list; + struct list_head cm_id_list; + struct list_head conn_list; + struct ib_device *dev; + struct ib_pd *pd; + struct ib_mr *mr; + struct rds_iw_mr_pool *mr_pool; + int page_shift; + int max_sge; + unsigned int max_wrs; + unsigned int dma_local_lkey:1; + spinlock_t spinlock; /* protect the above */ +}; + +/* bits for i_ack_flags */ +#define IB_ACK_IN_FLIGHT 0 +#define IB_ACK_REQUESTED 1 + +/* Magic WR_ID for ACKs */ +#define RDS_IW_ACK_WR_ID ((u64)0xffffffffffffffffULL) +#define RDS_IW_FAST_REG_WR_ID ((u64)0xefefefefefefefefULL) +#define RDS_IW_LOCAL_INV_WR_ID ((u64)0xdfdfdfdfdfdfdfdfULL) + +struct rds_iw_statistics { + uint64_t s_iw_connect_raced; + uint64_t s_iw_listen_closed_stale; + uint64_t s_iw_tx_cq_call; + uint64_t s_iw_tx_cq_event; + uint64_t s_iw_tx_ring_full; + uint64_t s_iw_tx_throttle; + uint64_t s_iw_tx_sg_mapping_failure; + uint64_t s_iw_tx_stalled; + uint64_t s_iw_tx_credit_updates; + uint64_t s_iw_rx_cq_call; + uint64_t s_iw_rx_cq_event; + uint64_t s_iw_rx_ring_empty; + uint64_t s_iw_rx_refill_from_cq; + uint64_t s_iw_rx_refill_from_thread; + uint64_t s_iw_rx_alloc_limit; + uint64_t s_iw_rx_credit_updates; + uint64_t s_iw_ack_sent; + uint64_t s_iw_ack_send_failure; + uint64_t s_iw_ack_send_delayed; + uint64_t s_iw_ack_send_piggybacked; + uint64_t s_iw_ack_received; + uint64_t s_iw_rdma_mr_alloc; + uint64_t s_iw_rdma_mr_free; + uint64_t s_iw_rdma_mr_used; + uint64_t s_iw_rdma_mr_pool_flush; + uint64_t s_iw_rdma_mr_pool_wait; + uint64_t s_iw_rdma_mr_pool_depleted; +}; + +extern struct workqueue_struct *rds_iw_wq; + +/* + * Fake ib_dma_sync_sg_for_{cpu,device} as long as ib_verbs.h + * doesn't define it. + */ +static inline void rds_iw_dma_sync_sg_for_cpu(struct ib_device *dev, + struct scatterlist *sg, unsigned int sg_dma_len, int direction) +{ + unsigned int i; + + for (i = 0; i < sg_dma_len; ++i) { + ib_dma_sync_single_for_cpu(dev, + ib_sg_dma_address(dev, &sg[i]), + ib_sg_dma_len(dev, &sg[i]), + direction); + } +} +#define ib_dma_sync_sg_for_cpu rds_iw_dma_sync_sg_for_cpu + +static inline void rds_iw_dma_sync_sg_for_device(struct ib_device *dev, + struct scatterlist *sg, unsigned int sg_dma_len, int direction) +{ + unsigned int i; + + for (i = 0; i < sg_dma_len; ++i) { + ib_dma_sync_single_for_device(dev, + ib_sg_dma_address(dev, &sg[i]), + ib_sg_dma_len(dev, &sg[i]), + direction); + } +} +#define ib_dma_sync_sg_for_device rds_iw_dma_sync_sg_for_device + +static inline u32 rds_iw_local_dma_lkey(struct rds_iw_connection *ic) +{ + return ic->i_dma_local_lkey ? ic->i_cm_id->device->local_dma_lkey : ic->i_mr->lkey; +} + +/* ib.c */ +extern struct rds_transport rds_iw_transport; +extern void rds_iw_add_one(struct ib_device *device); +extern void rds_iw_remove_one(struct ib_device *device); +extern struct ib_client rds_iw_client; + +extern unsigned int fastreg_pool_size; +extern unsigned int fastreg_message_size; + +extern spinlock_t iw_nodev_conns_lock; +extern struct list_head iw_nodev_conns; + +/* ib_cm.c */ +int rds_iw_conn_alloc(struct rds_connection *conn, gfp_t gfp); +void rds_iw_conn_free(void *arg); +int rds_iw_conn_connect(struct rds_connection *conn); +void rds_iw_conn_shutdown(struct rds_connection *conn); +void rds_iw_state_change(struct sock *sk); +int __init rds_iw_listen_init(void); +void rds_iw_listen_stop(void); +void __rds_iw_conn_error(struct rds_connection *conn, const char *, ...); +int rds_iw_cm_handle_connect(struct rdma_cm_id *cm_id, + struct rdma_cm_event *event); +int rds_iw_cm_initiate_connect(struct rdma_cm_id *cm_id); +void rds_iw_cm_connect_complete(struct rds_connection *conn, + struct rdma_cm_event *event); + + +#define rds_iw_conn_error(conn, fmt...) \ + __rds_iw_conn_error(conn, KERN_WARNING "RDS/IW: " fmt) + +/* ib_rdma.c */ +int rds_iw_update_cm_id(struct rds_iw_device *rds_iwdev, struct rdma_cm_id *cm_id); +int rds_iw_add_conn(struct rds_iw_device *rds_iwdev, struct rds_connection *conn); +void rds_iw_remove_nodev_conns(void); +void rds_iw_remove_conns(struct rds_iw_device *rds_iwdev); +struct rds_iw_mr_pool *rds_iw_create_mr_pool(struct rds_iw_device *); +void rds_iw_get_mr_info(struct rds_iw_device *rds_iwdev, struct rds_info_rdma_connection *iinfo); +void rds_iw_destroy_mr_pool(struct rds_iw_mr_pool *); +void *rds_iw_get_mr(struct scatterlist *sg, unsigned long nents, + struct rds_sock *rs, u32 *key_ret); +void rds_iw_sync_mr(void *trans_private, int dir); +void rds_iw_free_mr(void *trans_private, int invalidate); +void rds_iw_flush_mrs(void); +void rds_iw_remove_cm_id(struct rds_iw_device *rds_iwdev, struct rdma_cm_id *cm_id); + +/* ib_recv.c */ +int __init rds_iw_recv_init(void); +void rds_iw_recv_exit(void); +int rds_iw_recv(struct rds_connection *conn); +int rds_iw_recv_refill(struct rds_connection *conn, gfp_t kptr_gfp, + gfp_t page_gfp, int prefill); +void rds_iw_inc_purge(struct rds_incoming *inc); +void rds_iw_inc_free(struct rds_incoming *inc); +int rds_iw_inc_copy_to_user(struct rds_incoming *inc, struct iovec *iov, + size_t size); +void rds_iw_recv_cq_comp_handler(struct ib_cq *cq, void *context); +void rds_iw_recv_init_ring(struct rds_iw_connection *ic); +void rds_iw_recv_clear_ring(struct rds_iw_connection *ic); +void rds_iw_recv_init_ack(struct rds_iw_connection *ic); +void rds_iw_attempt_ack(struct rds_iw_connection *ic); +void rds_iw_ack_send_complete(struct rds_iw_connection *ic); +u64 rds_iw_piggyb_ack(struct rds_iw_connection *ic); + +/* ib_ring.c */ +void rds_iw_ring_init(struct rds_iw_work_ring *ring, u32 nr); +void rds_iw_ring_resize(struct rds_iw_work_ring *ring, u32 nr); +u32 rds_iw_ring_alloc(struct rds_iw_work_ring *ring, u32 val, u32 *pos); +void rds_iw_ring_free(struct rds_iw_work_ring *ring, u32 val); +void rds_iw_ring_unalloc(struct rds_iw_work_ring *ring, u32 val); +int rds_iw_ring_empty(struct rds_iw_work_ring *ring); +int rds_iw_ring_low(struct rds_iw_work_ring *ring); +u32 rds_iw_ring_oldest(struct rds_iw_work_ring *ring); +u32 rds_iw_ring_completed(struct rds_iw_work_ring *ring, u32 wr_id, u32 oldest); +extern wait_queue_head_t rds_iw_ring_empty_wait; + +/* ib_send.c */ +void rds_iw_xmit_complete(struct rds_connection *conn); +int rds_iw_xmit(struct rds_connection *conn, struct rds_message *rm, + unsigned int hdr_off, unsigned int sg, unsigned int off); +void rds_iw_send_cq_comp_handler(struct ib_cq *cq, void *context); +void rds_iw_send_init_ring(struct rds_iw_connection *ic); +void rds_iw_send_clear_ring(struct rds_iw_connection *ic); +int rds_iw_xmit_rdma(struct rds_connection *conn, struct rds_rdma_op *op); +void rds_iw_send_add_credits(struct rds_connection *conn, unsigned int credits); +void rds_iw_advertise_credits(struct rds_connection *conn, unsigned int posted); +int rds_iw_send_grab_credits(struct rds_iw_connection *ic, u32 wanted, + u32 *adv_credits, int need_posted); + +/* ib_stats.c */ +DECLARE_PER_CPU(struct rds_iw_statistics, rds_iw_stats); +#define rds_iw_stats_inc(member) rds_stats_inc_which(rds_iw_stats, member) +unsigned int rds_iw_stats_info_copy(struct rds_info_iterator *iter, + unsigned int avail); + +/* ib_sysctl.c */ +int __init rds_iw_sysctl_init(void); +void rds_iw_sysctl_exit(void); +extern unsigned long rds_iw_sysctl_max_send_wr; +extern unsigned long rds_iw_sysctl_max_recv_wr; +extern unsigned long rds_iw_sysctl_max_unsig_wrs; +extern unsigned long rds_iw_sysctl_max_unsig_bytes; +extern unsigned long rds_iw_sysctl_max_recv_allocation; +extern unsigned int rds_iw_sysctl_flow_control; +extern ctl_table rds_iw_sysctl_table[]; + +/* + * Helper functions for getting/setting the header and data SGEs in + * RDS packets (not RDMA) + */ +static inline struct ib_sge * +rds_iw_header_sge(struct rds_iw_connection *ic, struct ib_sge *sge) +{ + return &sge[0]; +} + +static inline struct ib_sge * +rds_iw_data_sge(struct rds_iw_connection *ic, struct ib_sge *sge) +{ + return &sge[1]; +} + +static inline void rds_iw_set_64bit(u64 *ptr, u64 val) +{ +#if BITS_PER_LONG == 64 + *ptr = val; +#else + set_64bit(ptr, val); +#endif +} + +#endif diff --git a/net/rds/iw_cm.c b/net/rds/iw_cm.c new file mode 100644 index 0000000..57ecb3d --- /dev/null +++ b/net/rds/iw_cm.c @@ -0,0 +1,750 @@ +/* + * Copyright (c) 2006 Oracle. All rights reserved. + * + * This software is available to you under a choice of one of two + * licenses. You may choose to be licensed under the terms of the GNU + * General Public License (GPL) Version 2, available from the file + * COPYING in the main directory of this source tree, or the + * OpenIB.org BSD license below: + * + * 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 + * copyright notice, this list of conditions and the following + * disclaimer in the documentation and/or other materials + * provided with the distribution. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + * + */ +#include <linux/kernel.h> +#include <linux/in.h> +#include <linux/vmalloc.h> + +#include "rds.h" +#include "iw.h" + +/* + * Set the selected protocol version + */ +static void rds_iw_set_protocol(struct rds_connection *conn, unsigned int version) +{ + conn->c_version = version; +} + +/* + * Set up flow control + */ +static void rds_iw_set_flow_control(struct rds_connection *conn, u32 credits) +{ + struct rds_iw_connection *ic = conn->c_transport_data; + + if (rds_iw_sysctl_flow_control && credits != 0) { + /* We're doing flow control */ + ic->i_flowctl = 1; + rds_iw_send_add_credits(conn, credits); + } else { + ic->i_flowctl = 0; + } +} + +/* + * Connection established. + * We get here for both outgoing and incoming connection. + */ +void rds_iw_cm_connect_complete(struct rds_connection *conn, struct rdma_cm_event *event) +{ + const struct rds_iw_connect_private *dp = NULL; + struct rds_iw_connection *ic = conn->c_transport_data; + struct rds_iw_device *rds_iwdev; + int err; + + if (event->param.conn.private_data_len) { + dp = event->param.conn.private_data; + + rds_iw_set_protocol(conn, + RDS_PROTOCOL(dp->dp_protocol_major, + dp->dp_protocol_minor)); + rds_iw_set_flow_control(conn, be32_to_cpu(dp->dp_credit)); + } + + /* update ib_device with this local ipaddr & conn */ + rds_iwdev = ib_get_client_data(ic->i_cm_id->device, &rds_iw_client); + err = rds_iw_update_cm_id(rds_iwdev, ic->i_cm_id); + if (err) + printk(KERN_ERR "rds_iw_update_ipaddr failed (%d)\n", err); + err = rds_iw_add_conn(rds_iwdev, conn); + if (err) + printk(KERN_ERR "rds_iw_add_conn failed (%d)\n", err); + + /* If the peer gave us the last packet it saw, process this as if + * we had received a regular ACK. */ + if (dp && dp->dp_ack_seq) + rds_send_drop_acked(conn, be64_to_cpu(dp->dp_ack_seq), NULL); + + printk(KERN_NOTICE "RDS/IW: connected to %pI4<->%pI4 version %u.%u%s\n", + &conn->c_laddr, &conn->c_faddr, + RDS_PROTOCOL_MAJOR(conn->c_version), + RDS_PROTOCOL_MINOR(conn->c_version), + ic->i_flowctl ? ", flow control" : ""); + + rds_connect_complete(conn); +} + +static void rds_iw_cm_fill_conn_param(struct rds_connection *conn, + struct rdma_conn_param *conn_param, + struct rds_iw_connect_private *dp, + u32 protocol_version) +{ + struct rds_iw_connection *ic = conn->c_transport_data; + + memset(conn_param, 0, sizeof(struct rdma_conn_param)); + /* XXX tune these? */ + conn_param->responder_resources = 1; + conn_param->initiator_depth = 1; + + if (dp) { + memset(dp, 0, sizeof(*dp)); + dp->dp_saddr = conn->c_laddr; + dp->dp_daddr = conn->c_faddr; + dp->dp_protocol_major = RDS_PROTOCOL_MAJOR(protocol_version); + dp->dp_protocol_minor = RDS_PROTOCOL_MINOR(protocol_version); + dp->dp_protocol_minor_mask = cpu_to_be16(RDS_IW_SUPPORTED_PROTOCOLS); + dp->dp_ack_seq = rds_iw_piggyb_ack(ic); + + /* Advertise flow control */ + if (ic->i_flowctl) { + unsigned int credits; + + credits = IB_GET_POST_CREDITS(atomic_read(&ic->i_credits)); + dp->dp_credit = cpu_to_be32(credits); + atomic_sub(IB_SET_POST_CREDITS(credits), &ic->i_credits); + } + + conn_param->private_data = dp; + conn_param->private_data_len = sizeof(*dp); + } +} + +static void rds_iw_cq_event_handler(struct ib_event *event, void *data) +{ + rdsdebug("event %u data %p\n", event->event, data); +} + +static void rds_iw_qp_event_handler(struct ib_event *event, void *data) +{ + struct rds_connection *conn = data; + struct rds_iw_connection *ic = conn->c_transport_data; + + rdsdebug("conn %p ic %p event %u\n", conn, ic, event->event); + + switch (event->event) { + case IB_EVENT_COMM_EST: + rdma_notify(ic->i_cm_id, IB_EVENT_COMM_EST); + break; + case IB_EVENT_QP_REQ_ERR: + case IB_EVENT_QP_FATAL: + default: + rds_iw_conn_error(conn, "RDS/IW: Fatal QP Event %u - connection %pI4->%pI4...reconnecting\n", + event->event, &conn->c_laddr, + &conn->c_faddr); + break; + } +} + +/* + * Create a QP + */ +static int rds_iw_init_qp_attrs(struct ib_qp_init_attr *attr, + struct rds_iw_device *rds_iwdev, + struct rds_iw_work_ring *send_ring, + void (*send_cq_handler)(struct ib_cq *, void *), + struct rds_iw_work_ring *recv_ring, + void (*recv_cq_handler)(struct ib_cq *, void *), + void *context) +{ + struct ib_device *dev = rds_iwdev->dev; + unsigned int send_size, recv_size; + int ret; + + /* The offset of 1 is to accomodate the additional ACK WR. */ + send_size = min_t(unsigned int, rds_iwdev->max_wrs, rds_iw_sysctl_max_send_wr + 1); + recv_size = min_t(unsigned int, rds_iwdev->max_wrs, rds_iw_sysctl_max_recv_wr + 1); + rds_iw_ring_resize(send_ring, send_size - 1); + rds_iw_ring_resize(recv_ring, recv_size - 1); + + memset(attr, 0, sizeof(*attr)); + attr->event_handler = rds_iw_qp_event_handler; + attr->qp_context = context; + attr->cap.max_send_wr = send_size; + attr->cap.max_recv_wr = recv_size; + attr->cap.max_send_sge = rds_iwdev->max_sge; + attr->cap.max_recv_sge = RDS_IW_RECV_SGE; + attr->sq_sig_type = IB_SIGNAL_REQ_WR; + attr->qp_type = IB_QPT_RC; + + attr->send_cq = ib_create_cq(dev, send_cq_handler, + rds_iw_cq_event_handler, + context, send_size, 0); + if (IS_ERR(attr->send_cq)) { + ret = PTR_ERR(attr->send_cq); + attr->send_cq = NULL; + rdsdebug("ib_create_cq send failed: %d\n", ret); + goto out; + } + + attr->recv_cq = ib_create_cq(dev, recv_cq_handler, + rds_iw_cq_event_handler, + context, recv_size, 0); + if (IS_ERR(attr->recv_cq)) { + ret = PTR_ERR(attr->recv_cq); + attr->recv_cq = NULL; + rdsdebug("ib_create_cq send failed: %d\n", ret); + goto out; + } + + ret = ib_req_notify_cq(attr->send_cq, IB_CQ_NEXT_COMP); + if (ret) { + rdsdebug("ib_req_notify_cq send failed: %d\n", ret); + goto out; + } + + ret = ib_req_notify_cq(attr->recv_cq, IB_CQ_SOLICITED); + if (ret) { + rdsdebug("ib_req_notify_cq recv failed: %d\n", ret); + goto out; + } + +out: + if (ret) { + if (attr->send_cq) + ib_destroy_cq(attr->send_cq); + if (attr->recv_cq) + ib_destroy_cq(attr->recv_cq); + } + return ret; +} + +/* + * This needs to be very careful to not leave IS_ERR pointers around for + * cleanup to trip over. + */ +static int rds_iw_setup_qp(struct rds_connection *conn) +{ + struct rds_iw_connection *ic = conn->c_transport_data; + struct ib_device *dev = ic->i_cm_id->device; + struct ib_qp_init_attr attr; + struct rds_iw_device *rds_iwdev; + int ret; + + /* rds_iw_add_one creates a rds_iw_device object per IB device, + * and allocates a protection domain, memory range and MR pool + * for each. If that fails for any reason, it will not register + * the rds_iwdev at all. + */ + rds_iwdev = ib_get_client_data(dev, &rds_iw_client); + if (rds_iwdev == NULL) { + if (printk_ratelimit()) + printk(KERN_NOTICE "RDS/IW: No client_data for device %s\n", + dev->name); + return -EOPNOTSUPP; + } + + /* Protection domain and memory range */ + ic->i_pd = rds_iwdev->pd; + ic->i_mr = rds_iwdev->mr; + + ret = rds_iw_init_qp_attrs(&attr, rds_iwdev, + &ic->i_send_ring, rds_iw_send_cq_comp_handler, + &ic->i_recv_ring, rds_iw_recv_cq_comp_handler, + conn); + if (ret < 0) + goto out; + + ic->i_send_cq = attr.send_cq; + ic->i_recv_cq = attr.recv_cq; + + /* + * XXX this can fail if max_*_wr is too large? Are we supposed + * to back off until we get a value that the hardware can support? + */ + ret = rdma_create_qp(ic->i_cm_id, ic->i_pd, &attr); + if (ret) { + rdsdebug("rdma_create_qp failed: %d\n", ret); + goto out; + } + + ic->i_send_hdrs = ib_dma_alloc_coherent(dev, + ic->i_send_ring.w_nr * + sizeof(struct rds_header), + &ic->i_send_hdrs_dma, GFP_KERNEL); + if (ic->i_send_hdrs == NULL) { + ret = -ENOMEM; + rdsdebug("ib_dma_alloc_coherent send failed\n"); + goto out; + } + + ic->i_recv_hdrs = ib_dma_alloc_coherent(dev, + ic->i_recv_ring.w_nr * + sizeof(struct rds_header), + &ic->i_recv_hdrs_dma, GFP_KERNEL); + if (ic->i_recv_hdrs == NULL) { + ret = -ENOMEM; + rdsdebug("ib_dma_alloc_coherent recv failed\n"); + goto out; + } + + ic->i_ack = ib_dma_alloc_coherent(dev, sizeof(struct rds_header), + &ic->i_ack_dma, GFP_KERNEL); + if (ic->i_ack == NULL) { + ret = -ENOMEM; + rdsdebug("ib_dma_alloc_coherent ack failed\n"); + goto out; + } + + ic->i_sends = vmalloc(ic->i_send_ring.w_nr * sizeof(struct rds_iw_send_work)); + if (ic->i_sends == NULL) { + ret = -ENOMEM; + rdsdebug("send allocation failed\n"); + goto out; + } + rds_iw_send_init_ring(ic); + + ic->i_recvs = vmalloc(ic->i_recv_ring.w_nr * sizeof(struct rds_iw_recv_work)); + if (ic->i_recvs == NULL) { + ret = -ENOMEM; + rdsdebug("recv allocation failed\n"); + goto out; + } + + rds_iw_recv_init_ring(ic); + rds_iw_recv_init_ack(ic); + + /* Post receive buffers - as a side effect, this will update + * the posted credit count. */ + rds_iw_recv_refill(conn, GFP_KERNEL, GFP_HIGHUSER, 1); + + rdsdebug("conn %p pd %p mr %p cq %p %p\n", conn, ic->i_pd, ic->i_mr, + ic->i_send_cq, ic->i_recv_cq); + +out: + return ret; +} + +static u32 rds_iw_protocol_compatible(const struct rds_iw_connect_private *dp) +{ + u16 common; + u32 version = 0; + + /* rdma_cm private data is odd - when there is any private data in the + * request, we will be given a pretty large buffer without telling us the + * original size. The only way to tell the difference is by looking at + * the contents, which are initialized to zero. + * If the protocol version fields aren't set, this is a connection attempt + * from an older version. This could could be 3.0 or 2.0 - we can't tell. + * We really should have changed this for OFED 1.3 :-( */ + if (dp->dp_protocol_major == 0) + return RDS_PROTOCOL_3_0; + + common = be16_to_cpu(dp->dp_protocol_minor_mask) & RDS_IW_SUPPORTED_PROTOCOLS; + if (dp->dp_protocol_major == 3 && common) { + version = RDS_PROTOCOL_3_0; + while ((common >>= 1) != 0) + version++; + } else if (printk_ratelimit()) { + printk(KERN_NOTICE "RDS: Connection from %pI4 using " + "incompatible protocol version %u.%u\n", + &dp->dp_saddr, + dp->dp_protocol_major, + dp->dp_protocol_minor); + } + return version; +} + +int rds_iw_cm_handle_connect(struct rdma_cm_id *cm_id, + struct rdma_cm_event *event) +{ + const struct rds_iw_connect_private *dp = event->param.conn.private_data; + struct rds_iw_connect_private dp_rep; + struct rds_connection *conn = NULL; + struct rds_iw_connection *ic = NULL; + struct rdma_conn_param conn_param; + struct rds_iw_device *rds_iwdev; + u32 version; + int err, destroy = 1; + + /* Check whether the remote protocol version matches ours. */ + version = rds_iw_protocol_compatible(dp); + if (!version) + goto out; + + rdsdebug("saddr %pI4 daddr %pI4 RDSv%u.%u\n", + &dp->dp_saddr, &dp->dp_daddr, + RDS_PROTOCOL_MAJOR(version), RDS_PROTOCOL_MINOR(version)); + + conn = rds_conn_create(dp->dp_daddr, dp->dp_saddr, &rds_iw_transport, + GFP_KERNEL); + if (IS_ERR(conn)) { + rdsdebug("rds_conn_create failed (%ld)\n", PTR_ERR(conn)); + conn = NULL; + goto out; + } + + /* + * The connection request may occur while the + * previous connection exist, e.g. in case of failover. + * But as connections may be initiated simultaneously + * by both hosts, we have a random backoff mechanism - + * see the comment above rds_queue_reconnect() + */ + mutex_lock(&conn->c_cm_lock); + if (!rds_conn_transition(conn, RDS_CONN_DOWN, RDS_CONN_CONNECTING)) { + if (rds_conn_state(conn) == RDS_CONN_UP) { + rdsdebug("incoming connect while connecting\n"); + rds_conn_drop(conn); + rds_iw_stats_inc(s_iw_listen_closed_stale); + } else + if (rds_conn_state(conn) == RDS_CONN_CONNECTING) { + /* Wait and see - our connect may still be succeeding */ + rds_iw_stats_inc(s_iw_connect_raced); + } + mutex_unlock(&conn->c_cm_lock); + goto out; + } + + ic = conn->c_transport_data; + + rds_iw_set_protocol(conn, version); + rds_iw_set_flow_control(conn, be32_to_cpu(dp->dp_credit)); + + /* If the peer gave us the last packet it saw, process this as if + * we had received a regular ACK. */ + if (dp->dp_ack_seq) + rds_send_drop_acked(conn, be64_to_cpu(dp->dp_ack_seq), NULL); + + BUG_ON(cm_id->context); + BUG_ON(ic->i_cm_id); + + ic->i_cm_id = cm_id; + cm_id->context = conn; + + rds_iwdev = ib_get_client_data(cm_id->device, &rds_iw_client); + ic->i_dma_local_lkey = rds_iwdev->dma_local_lkey; + + /* We got halfway through setting up the ib_connection, if we + * fail now, we have to take the long route out of this mess. */ + destroy = 0; + + err = rds_iw_setup_qp(conn); + if (err) { + rds_iw_conn_error(conn, "rds_iw_setup_qp failed (%d)\n", err); + goto out; + } + + rds_iw_cm_fill_conn_param(conn, &conn_param, &dp_rep, version); + + /* rdma_accept() calls rdma_reject() internally if it fails */ + err = rdma_accept(cm_id, &conn_param); + mutex_unlock(&conn->c_cm_lock); + if (err) { + rds_iw_conn_error(conn, "rdma_accept failed (%d)\n", err); + goto out; + } + + return 0; + +out: + rdma_reject(cm_id, NULL, 0); + return destroy; +} + + +int rds_iw_cm_initiate_connect(struct rdma_cm_id *cm_id) +{ + struct rds_connection *conn = cm_id->context; + struct rds_iw_connection *ic = conn->c_transport_data; + struct rdma_conn_param conn_param; + struct rds_iw_connect_private dp; + int ret; + + /* If the peer doesn't do protocol negotiation, we must + * default to RDSv3.0 */ + rds_iw_set_protocol(conn, RDS_PROTOCOL_3_0); + ic->i_flowctl = rds_iw_sysctl_flow_control; /* advertise flow control */ + + ret = rds_iw_setup_qp(conn); + if (ret) { + rds_iw_conn_error(conn, "rds_iw_setup_qp failed (%d)\n", ret); + goto out; + } + + rds_iw_cm_fill_conn_param(conn, &conn_param, &dp, RDS_PROTOCOL_VERSION); + + ret = rdma_connect(cm_id, &conn_param); + if (ret) + rds_iw_conn_error(conn, "rdma_connect failed (%d)\n", ret); + +out: + /* Beware - returning non-zero tells the rdma_cm to destroy + * the cm_id. We should certainly not do it as long as we still + * "own" the cm_id. */ + if (ret) { + struct rds_iw_connection *ic = conn->c_transport_data; + + if (ic->i_cm_id == cm_id) + ret = 0; + } + return ret; +} + +int rds_iw_conn_connect(struct rds_connection *conn) +{ + struct rds_iw_connection *ic = conn->c_transport_data; + struct rds_iw_device *rds_iwdev; + struct sockaddr_in src, dest; + int ret; + + /* XXX I wonder what affect the port space has */ + /* delegate cm event handler to rdma_transport */ + ic->i_cm_id = rdma_create_id(rds_rdma_cm_event_handler, conn, + RDMA_PS_TCP); + if (IS_ERR(ic->i_cm_id)) { + ret = PTR_ERR(ic->i_cm_id); + ic->i_cm_id = NULL; + rdsdebug("rdma_create_id() failed: %d\n", ret); + goto out; + } + + rdsdebug("created cm id %p for conn %p\n", ic->i_cm_id, conn); + + src.sin_family = AF_INET; + src.sin_addr.s_addr = (__force u32)conn->c_laddr; + src.sin_port = (__force u16)htons(0); + + /* First, bind to the local address and device. */ + ret = rdma_bind_addr(ic->i_cm_id, (struct sockaddr *) &src); + if (ret) { + rdsdebug("rdma_bind_addr(%pI4) failed: %d\n", + &conn->c_laddr, ret); + rdma_destroy_id(ic->i_cm_id); + ic->i_cm_id = NULL; + goto out; + } + + rds_iwdev = ib_get_client_data(ic->i_cm_id->device, &rds_iw_client); + ic->i_dma_local_lkey = rds_iwdev->dma_local_lkey; + + dest.sin_family = AF_INET; + dest.sin_addr.s_addr = (__force u32)conn->c_faddr; + dest.sin_port = (__force u16)htons(RDS_PORT); + + ret = rdma_resolve_addr(ic->i_cm_id, (struct sockaddr *)&src, + (struct sockaddr *)&dest, + RDS_RDMA_RESOLVE_TIMEOUT_MS); + if (ret) { + rdsdebug("addr resolve failed for cm id %p: %d\n", ic->i_cm_id, + ret); + rdma_destroy_id(ic->i_cm_id); + ic->i_cm_id = NULL; + } + +out: + return ret; +} + +/* + * This is so careful about only cleaning up resources that were built up + * so that it can be called at any point during startup. In fact it + * can be called multiple times for a given connection. + */ +void rds_iw_conn_shutdown(struct rds_connection *conn) +{ + struct rds_iw_connection *ic = conn->c_transport_data; + int err = 0; + struct ib_qp_attr qp_attr; + + rdsdebug("cm %p pd %p cq %p %p qp %p\n", ic->i_cm_id, + ic->i_pd, ic->i_send_cq, ic->i_recv_cq, + ic->i_cm_id ? ic->i_cm_id->qp : NULL); + + if (ic->i_cm_id) { + struct ib_device *dev = ic->i_cm_id->device; + + rdsdebug("disconnecting cm %p\n", ic->i_cm_id); + err = rdma_disconnect(ic->i_cm_id); + if (err) { + /* Actually this may happen quite frequently, when + * an outgoing connect raced with an incoming connect. + */ + rdsdebug("rds_iw_conn_shutdown: failed to disconnect," + " cm: %p err %d\n", ic->i_cm_id, err); + } + + if (ic->i_cm_id->qp) { + qp_attr.qp_state = IB_QPS_ERR; + ib_modify_qp(ic->i_cm_id->qp, &qp_attr, IB_QP_STATE); + } + + wait_event(rds_iw_ring_empty_wait, + rds_iw_ring_empty(&ic->i_send_ring) && + rds_iw_ring_empty(&ic->i_recv_ring)); + + if (ic->i_send_hdrs) + ib_dma_free_coherent(dev, + ic->i_send_ring.w_nr * + sizeof(struct rds_header), + ic->i_send_hdrs, + ic->i_send_hdrs_dma); + + if (ic->i_recv_hdrs) + ib_dma_free_coherent(dev, + ic->i_recv_ring.w_nr * + sizeof(struct rds_header), + ic->i_recv_hdrs, + ic->i_recv_hdrs_dma); + + if (ic->i_ack) + ib_dma_free_coherent(dev, sizeof(struct rds_header), + ic->i_ack, ic->i_ack_dma); + + if (ic->i_sends) + rds_iw_send_clear_ring(ic); + if (ic->i_recvs) + rds_iw_recv_clear_ring(ic); + + if (ic->i_cm_id->qp) + rdma_destroy_qp(ic->i_cm_id); + if (ic->i_send_cq) + ib_destroy_cq(ic->i_send_cq); + if (ic->i_recv_cq) + ib_destroy_cq(ic->i_recv_cq); + + /* + * If associated with an rds_iw_device: + * Move connection back to the nodev list. + * Remove cm_id from the device cm_id list. + */ + if (ic->rds_iwdev) { + + spin_lock_irq(&ic->rds_iwdev->spinlock); + BUG_ON(list_empty(&ic->iw_node)); + list_del(&ic->iw_node); + spin_unlock_irq(&ic->rds_iwdev->spinlock); + + spin_lock_irq(&iw_nodev_conns_lock); + list_add_tail(&ic->iw_node, &iw_nodev_conns); + spin_unlock_irq(&iw_nodev_conns_lock); + rds_iw_remove_cm_id(ic->rds_iwdev, ic->i_cm_id); + ic->rds_iwdev = NULL; + } + + rdma_destroy_id(ic->i_cm_id); + + ic->i_cm_id = NULL; + ic->i_pd = NULL; + ic->i_mr = NULL; + ic->i_send_cq = NULL; + ic->i_recv_cq = NULL; + ic->i_send_hdrs = NULL; + ic->i_recv_hdrs = NULL; + ic->i_ack = NULL; + } + BUG_ON(ic->rds_iwdev); + + /* Clear pending transmit */ + if (ic->i_rm) { + rds_message_put(ic->i_rm); + ic->i_rm = NULL; + } + + /* Clear the ACK state */ + clear_bit(IB_ACK_IN_FLIGHT, &ic->i_ack_flags); + rds_iw_set_64bit(&ic->i_ack_next, 0); + ic->i_ack_recv = 0; + + /* Clear flow control state */ + ic->i_flowctl = 0; + atomic_set(&ic->i_credits, 0); + + rds_iw_ring_init(&ic->i_send_ring, rds_iw_sysctl_max_send_wr); + rds_iw_ring_init(&ic->i_recv_ring, rds_iw_sysctl_max_recv_wr); + + if (ic->i_iwinc) { + rds_inc_put(&ic->i_iwinc->ii_inc); + ic->i_iwinc = NULL; + } + + vfree(ic->i_sends); + ic->i_sends = NULL; + vfree(ic->i_recvs); + ic->i_recvs = NULL; + rdsdebug("shutdown complete\n"); +} + +int rds_iw_conn_alloc(struct rds_connection *conn, gfp_t gfp) +{ + struct rds_iw_connection *ic; + unsigned long flags; + + /* XXX too lazy? */ + ic = kzalloc(sizeof(struct rds_iw_connection), GFP_KERNEL); + if (ic == NULL) + return -ENOMEM; + + INIT_LIST_HEAD(&ic->iw_node); + mutex_init(&ic->i_recv_mutex); + + /* + * rds_iw_conn_shutdown() waits for these to be emptied so they + * must be initialized before it can be called. + */ + rds_iw_ring_init(&ic->i_send_ring, rds_iw_sysctl_max_send_wr); + rds_iw_ring_init(&ic->i_recv_ring, rds_iw_sysctl_max_recv_wr); + + ic->conn = conn; + conn->c_transport_data = ic; + + spin_lock_irqsave(&iw_nodev_conns_lock, flags); + list_add_tail(&ic->iw_node, &iw_nodev_conns); + spin_unlock_irqrestore(&iw_nodev_conns_lock, flags); + + + rdsdebug("conn %p conn ic %p\n", conn, conn->c_transport_data); + return 0; +} + +void rds_iw_conn_free(void *arg) +{ + struct rds_iw_connection *ic = arg; + rdsdebug("ic %p\n", ic); + list_del(&ic->iw_node); + kfree(ic); +} + +/* + * An error occurred on the connection + */ +void +__rds_iw_conn_error(struct rds_connection *conn, const char *fmt, ...) +{ + va_list ap; + + rds_conn_drop(conn); + + va_start(ap, fmt); + vprintk(fmt, ap); + va_end(ap); +} diff --git a/net/rds/iw_rdma.c b/net/rds/iw_rdma.c new file mode 100644 index 0000000..1c02a8f --- /dev/null +++ b/net/rds/iw_rdma.c @@ -0,0 +1,888 @@ +/* + * Copyright (c) 2006 Oracle. All rights reserved. + * + * This software is available to you under a choice of one of two + * licenses. You may choose to be licensed under the terms of the GNU + * General Public License (GPL) Version 2, available from the file + * COPYING in the main directory of this source tree, or the + * OpenIB.org BSD license below: + * + * 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 + * copyright notice, this list of conditions and the following + * disclaimer in the documentation and/or other materials + * provided with the distribution. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + * + */ +#include <linux/kernel.h> + +#include "rds.h" +#include "rdma.h" +#include "iw.h" + + +/* + * This is stored as mr->r_trans_private. + */ +struct rds_iw_mr { + struct rds_iw_device *device; + struct rds_iw_mr_pool *pool; + struct rdma_cm_id *cm_id; + + struct ib_mr *mr; + struct ib_fast_reg_page_list *page_list; + + struct rds_iw_mapping mapping; + unsigned char remap_count; +}; + +/* + * Our own little MR pool + */ +struct rds_iw_mr_pool { + struct rds_iw_device *device; /* back ptr to the device that owns us */ + + struct mutex flush_lock; /* serialize fmr invalidate */ + struct work_struct flush_worker; /* flush worker */ + + spinlock_t list_lock; /* protect variables below */ + atomic_t item_count; /* total # of MRs */ + atomic_t dirty_count; /* # dirty of MRs */ + struct list_head dirty_list; /* dirty mappings */ + struct list_head clean_list; /* unused & unamapped MRs */ + atomic_t free_pinned; /* memory pinned by free MRs */ + unsigned long max_message_size; /* in pages */ + unsigned long max_items; + unsigned long max_items_soft; + unsigned long max_free_pinned; + int max_pages; +}; + +static int rds_iw_flush_mr_pool(struct rds_iw_mr_pool *pool, int free_all); +static void rds_iw_mr_pool_flush_worker(struct work_struct *work); +static int rds_iw_init_fastreg(struct rds_iw_mr_pool *pool, struct rds_iw_mr *ibmr); +static int rds_iw_map_fastreg(struct rds_iw_mr_pool *pool, + struct rds_iw_mr *ibmr, + struct scatterlist *sg, unsigned int nents); +static void rds_iw_free_fastreg(struct rds_iw_mr_pool *pool, struct rds_iw_mr *ibmr); +static unsigned int rds_iw_unmap_fastreg_list(struct rds_iw_mr_pool *pool, + struct list_head *unmap_list, + struct list_head *kill_list); +static void rds_iw_destroy_fastreg(struct rds_iw_mr_pool *pool, struct rds_iw_mr *ibmr); + +static int rds_iw_get_device(struct rds_sock *rs, struct rds_iw_device **rds_iwdev, struct rdma_cm_id **cm_id) +{ + struct rds_iw_device *iwdev; + struct rds_iw_cm_id *i_cm_id; + + *rds_iwdev = NULL; + *cm_id = NULL; + + list_for_each_entry(iwdev, &rds_iw_devices, list) { + spin_lock_irq(&iwdev->spinlock); + list_for_each_entry(i_cm_id, &iwdev->cm_id_list, list) { + struct sockaddr_in *src_addr, *dst_addr; + + src_addr = (struct sockaddr_in *)&i_cm_id->cm_id->route.addr.src_addr; + dst_addr = (struct sockaddr_in *)&i_cm_id->cm_id->route.addr.dst_addr; + + rdsdebug("local ipaddr = %x port %d, " + "remote ipaddr = %x port %d" + "..looking for %x port %d, " + "remote ipaddr = %x port %d\n", + src_addr->sin_addr.s_addr, + src_addr->sin_port, + dst_addr->sin_addr.s_addr, + dst_addr->sin_port, + rs->rs_bound_addr, + rs->rs_bound_port, + rs->rs_conn_addr, + rs->rs_conn_port); +#ifdef WORKING_TUPLE_DETECTION + if (src_addr->sin_addr.s_addr == rs->rs_bound_addr && + src_addr->sin_port == rs->rs_bound_port && + dst_addr->sin_addr.s_addr == rs->rs_conn_addr && + dst_addr->sin_port == rs->rs_conn_port) { +#else + /* FIXME - needs to compare the local and remote + * ipaddr/port tuple, but the ipaddr is the only + * available infomation in the rds_sock (as the rest are + * zero'ed. It doesn't appear to be properly populated + * during connection setup... + */ + if (src_addr->sin_addr.s_addr == rs->rs_bound_addr) { +#endif + spin_unlock_irq(&iwdev->spinlock); + *rds_iwdev = iwdev; + *cm_id = i_cm_id->cm_id; + return 0; + } + } + spin_unlock_irq(&iwdev->spinlock); + } + + return 1; +} + +static int rds_iw_add_cm_id(struct rds_iw_device *rds_iwdev, struct rdma_cm_id *cm_id) +{ + struct rds_iw_cm_id *i_cm_id; + + i_cm_id = kmalloc(sizeof *i_cm_id, GFP_KERNEL); + if (!i_cm_id) + return -ENOMEM; + + i_cm_id->cm_id = cm_id; + + spin_lock_irq(&rds_iwdev->spinlock); + list_add_tail(&i_cm_id->list, &rds_iwdev->cm_id_list); + spin_unlock_irq(&rds_iwdev->spinlock); + + return 0; +} + +void rds_iw_remove_cm_id(struct rds_iw_device *rds_iwdev, struct rdma_cm_id *cm_id) +{ + struct rds_iw_cm_id *i_cm_id; + + spin_lock_irq(&rds_iwdev->spinlock); + list_for_each_entry(i_cm_id, &rds_iwdev->cm_id_list, list) { + if (i_cm_id->cm_id == cm_id) { + list_del(&i_cm_id->list); + kfree(i_cm_id); + break; + } + } + spin_unlock_irq(&rds_iwdev->spinlock); +} + + +int rds_iw_update_cm_id(struct rds_iw_device *rds_iwdev, struct rdma_cm_id *cm_id) +{ + struct sockaddr_in *src_addr, *dst_addr; + struct rds_iw_device *rds_iwdev_old; + struct rds_sock rs; + struct rdma_cm_id *pcm_id; + int rc; + + src_addr = (struct sockaddr_in *)&cm_id->route.addr.src_addr; + dst_addr = (struct sockaddr_in *)&cm_id->route.addr.dst_addr; + + rs.rs_bound_addr = src_addr->sin_addr.s_addr; + rs.rs_bound_port = src_addr->sin_port; + rs.rs_conn_addr = dst_addr->sin_addr.s_addr; + rs.rs_conn_port = dst_addr->sin_port; + + rc = rds_iw_get_device(&rs, &rds_iwdev_old, &pcm_id); + if (rc) + rds_iw_remove_cm_id(rds_iwdev, cm_id); + + return rds_iw_add_cm_id(rds_iwdev, cm_id); +} + +int rds_iw_add_conn(struct rds_iw_device *rds_iwdev, struct rds_connection *conn) +{ + struct rds_iw_connection *ic = conn->c_transport_data; + + /* conn was previously on the nodev_conns_list */ + spin_lock_irq(&iw_nodev_conns_lock); + BUG_ON(list_empty(&iw_nodev_conns)); + BUG_ON(list_empty(&ic->iw_node)); + list_del(&ic->iw_node); + spin_unlock_irq(&iw_nodev_conns_lock); + + spin_lock_irq(&rds_iwdev->spinlock); + list_add_tail(&ic->iw_node, &rds_iwdev->conn_list); + spin_unlock_irq(&rds_iwdev->spinlock); + + ic->rds_iwdev = rds_iwdev; + + return 0; +} + +void rds_iw_remove_nodev_conns(void) +{ + struct rds_iw_connection *ic, *_ic; + LIST_HEAD(tmp_list); + + /* avoid calling conn_destroy with irqs off */ + spin_lock_irq(&iw_nodev_conns_lock); + list_splice(&iw_nodev_conns, &tmp_list); + INIT_LIST_HEAD(&iw_nodev_conns); + spin_unlock_irq(&iw_nodev_conns_lock); + + list_for_each_entry_safe(ic, _ic, &tmp_list, iw_node) { + if (ic->conn->c_passive) + rds_conn_destroy(ic->conn->c_passive); + rds_conn_destroy(ic->conn); + } +} + +void rds_iw_remove_conns(struct rds_iw_device *rds_iwdev) +{ + struct rds_iw_connection *ic, *_ic; + LIST_HEAD(tmp_list); + + /* avoid calling conn_destroy with irqs off */ + spin_lock_irq(&rds_iwdev->spinlock); + list_splice(&rds_iwdev->conn_list, &tmp_list); + INIT_LIST_HEAD(&rds_iwdev->conn_list); + spin_unlock_irq(&rds_iwdev->spinlock); + + list_for_each_entry_safe(ic, _ic, &tmp_list, iw_node) { + if (ic->conn->c_passive) + rds_conn_destroy(ic->conn->c_passive); + rds_conn_destroy(ic->conn); + } +} + +static void rds_iw_set_scatterlist(struct rds_iw_scatterlist *sg, + struct scatterlist *list, unsigned int sg_len) +{ + sg->list = list; + sg->len = sg_len; + sg->dma_len = 0; + sg->dma_npages = 0; + sg->bytes = 0; +} + +static u64 *rds_iw_map_scatterlist(struct rds_iw_device *rds_iwdev, + struct rds_iw_scatterlist *sg, + unsigned int dma_page_shift) +{ + struct ib_device *dev = rds_iwdev->dev; + u64 *dma_pages = NULL; + u64 dma_mask; + unsigned int dma_page_size; + int i, j, ret; + + dma_page_size = 1 << dma_page_shift; + dma_mask = dma_page_size - 1; + + WARN_ON(sg->dma_len); + + sg->dma_len = ib_dma_map_sg(dev, sg->list, sg->len, DMA_BIDIRECTIONAL); + if (unlikely(!sg->dma_len)) { + printk(KERN_WARNING "RDS/IW: dma_map_sg failed!\n"); + return ERR_PTR(-EBUSY); + } + + sg->bytes = 0; + sg->dma_npages = 0; + + ret = -EINVAL; + for (i = 0; i < sg->dma_len; ++i) { + unsigned int dma_len = ib_sg_dma_len(dev, &sg->list[i]); + u64 dma_addr = ib_sg_dma_address(dev, &sg->list[i]); + u64 end_addr; + + sg->bytes += dma_len; + + end_addr = dma_addr + dma_len; + if (dma_addr & dma_mask) { + if (i > 0) + goto out_unmap; + dma_addr &= ~dma_mask; + } + if (end_addr & dma_mask) { + if (i < sg->dma_len - 1) + goto out_unmap; + end_addr = (end_addr + dma_mask) & ~dma_mask; + } + + sg->dma_npages += (end_addr - dma_addr) >> dma_page_shift; + } + + /* Now gather the dma addrs into one list */ + if (sg->dma_npages > fastreg_message_size) + goto out_unmap; + + dma_pages = kmalloc(sizeof(u64) * sg->dma_npages, GFP_ATOMIC); + if (!dma_pages) { + ret = -ENOMEM; + goto out_unmap; + } + + for (i = j = 0; i < sg->dma_len; ++i) { + unsigned int dma_len = ib_sg_dma_len(dev, &sg->list[i]); + u64 dma_addr = ib_sg_dma_address(dev, &sg->list[i]); + u64 end_addr; + + end_addr = dma_addr + dma_len; + dma_addr &= ~dma_mask; + for (; dma_addr < end_addr; dma_addr += dma_page_size) + dma_pages[j++] = dma_addr; + BUG_ON(j > sg->dma_npages); + } + + return dma_pages; + +out_unmap: + ib_dma_unmap_sg(rds_iwdev->dev, sg->list, sg->len, DMA_BIDIRECTIONAL); + sg->dma_len = 0; + kfree(dma_pages); + return ERR_PTR(ret); +} + + +struct rds_iw_mr_pool *rds_iw_create_mr_pool(struct rds_iw_device *rds_iwdev) +{ + struct rds_iw_mr_pool *pool; + + pool = kzalloc(sizeof(*pool), GFP_KERNEL); + if (!pool) { + printk(KERN_WARNING "RDS/IW: rds_iw_create_mr_pool alloc error\n"); + return ERR_PTR(-ENOMEM); + } + + pool->device = rds_iwdev; + INIT_LIST_HEAD(&pool->dirty_list); + INIT_LIST_HEAD(&pool->clean_list); + mutex_init(&pool->flush_lock); + spin_lock_init(&pool->list_lock); + INIT_WORK(&pool->flush_worker, rds_iw_mr_pool_flush_worker); + + pool->max_message_size = fastreg_message_size; + pool->max_items = fastreg_pool_size; + pool->max_free_pinned = pool->max_items * pool->max_message_size / 4; + pool->max_pages = fastreg_message_size; + + /* We never allow more than max_items MRs to be allocated. + * When we exceed more than max_items_soft, we start freeing + * items more aggressively. + * Make sure that max_items > max_items_soft > max_items / 2 + */ + pool->max_items_soft = pool->max_items * 3 / 4; + + return pool; +} + +void rds_iw_get_mr_info(struct rds_iw_device *rds_iwdev, struct rds_info_rdma_connection *iinfo) +{ + struct rds_iw_mr_pool *pool = rds_iwdev->mr_pool; + + iinfo->rdma_mr_max = pool->max_items; + iinfo->rdma_mr_size = pool->max_pages; +} + +void rds_iw_destroy_mr_pool(struct rds_iw_mr_pool *pool) +{ + flush_workqueue(rds_wq); + rds_iw_flush_mr_pool(pool, 1); + BUG_ON(atomic_read(&pool->item_count)); + BUG_ON(atomic_read(&pool->free_pinned)); + kfree(pool); +} + +static inline struct rds_iw_mr *rds_iw_reuse_fmr(struct rds_iw_mr_pool *pool) +{ + struct rds_iw_mr *ibmr = NULL; + unsigned long flags; + + spin_lock_irqsave(&pool->list_lock, flags); + if (!list_empty(&pool->clean_list)) { + ibmr = list_entry(pool->clean_list.next, struct rds_iw_mr, mapping.m_list); + list_del_init(&ibmr->mapping.m_list); + } + spin_unlock_irqrestore(&pool->list_lock, flags); + + return ibmr; +} + +static struct rds_iw_mr *rds_iw_alloc_mr(struct rds_iw_device *rds_iwdev) +{ + struct rds_iw_mr_pool *pool = rds_iwdev->mr_pool; + struct rds_iw_mr *ibmr = NULL; + int err = 0, iter = 0; + + while (1) { + ibmr = rds_iw_reuse_fmr(pool); + if (ibmr) + return ibmr; + + /* No clean MRs - now we have the choice of either + * allocating a fresh MR up to the limit imposed by the + * driver, or flush any dirty unused MRs. + * We try to avoid stalling in the send path if possible, + * so we allocate as long as we're allowed to. + * + * We're fussy with enforcing the FMR limit, though. If the driver + * tells us we can't use more than N fmrs, we shouldn't start + * arguing with it */ + if (atomic_inc_return(&pool->item_count) <= pool->max_items) + break; + + atomic_dec(&pool->item_count); + + if (++iter > 2) { + rds_iw_stats_inc(s_iw_rdma_mr_pool_depleted); + return ERR_PTR(-EAGAIN); + } + + /* We do have some empty MRs. Flush them out. */ + rds_iw_stats_inc(s_iw_rdma_mr_pool_wait); + rds_iw_flush_mr_pool(pool, 0); + } + + ibmr = kzalloc(sizeof(*ibmr), GFP_KERNEL); + if (!ibmr) { + err = -ENOMEM; + goto out_no_cigar; + } + + spin_lock_init(&ibmr->mapping.m_lock); + INIT_LIST_HEAD(&ibmr->mapping.m_list); + ibmr->mapping.m_mr = ibmr; + + err = rds_iw_init_fastreg(pool, ibmr); + if (err) + goto out_no_cigar; + + rds_iw_stats_inc(s_iw_rdma_mr_alloc); + return ibmr; + +out_no_cigar: + if (ibmr) { + rds_iw_destroy_fastreg(pool, ibmr); + kfree(ibmr); + } + atomic_dec(&pool->item_count); + return ERR_PTR(err); +} + +void rds_iw_sync_mr(void *trans_private, int direction) +{ + struct rds_iw_mr *ibmr = trans_private; + struct rds_iw_device *rds_iwdev = ibmr->device; + + switch (direction) { + case DMA_FROM_DEVICE: + ib_dma_sync_sg_for_cpu(rds_iwdev->dev, ibmr->mapping.m_sg.list, + ibmr->mapping.m_sg.dma_len, DMA_BIDIRECTIONAL); + break; + case DMA_TO_DEVICE: + ib_dma_sync_sg_for_device(rds_iwdev->dev, ibmr->mapping.m_sg.list, + ibmr->mapping.m_sg.dma_len, DMA_BIDIRECTIONAL); + break; + } +} + +static inline unsigned int rds_iw_flush_goal(struct rds_iw_mr_pool *pool, int free_all) +{ + unsigned int item_count; + + item_count = atomic_read(&pool->item_count); + if (free_all) + return item_count; + + return 0; +} + +/* + * Flush our pool of MRs. + * At a minimum, all currently unused MRs are unmapped. + * If the number of MRs allocated exceeds the limit, we also try + * to free as many MRs as needed to get back to this limit. + */ +static int rds_iw_flush_mr_pool(struct rds_iw_mr_pool *pool, int free_all) +{ + struct rds_iw_mr *ibmr, *next; + LIST_HEAD(unmap_list); + LIST_HEAD(kill_list); + unsigned long flags; + unsigned int nfreed = 0, ncleaned = 0, free_goal; + int ret = 0; + + rds_iw_stats_inc(s_iw_rdma_mr_pool_flush); + + mutex_lock(&pool->flush_lock); + + spin_lock_irqsave(&pool->list_lock, flags); + /* Get the list of all mappings to be destroyed */ + list_splice_init(&pool->dirty_list, &unmap_list); + if (free_all) + list_splice_init(&pool->clean_list, &kill_list); + spin_unlock_irqrestore(&pool->list_lock, flags); + + free_goal = rds_iw_flush_goal(pool, free_all); + + /* Batched invalidate of dirty MRs. + * For FMR based MRs, the mappings on the unmap list are + * actually members of an ibmr (ibmr->mapping). They either + * migrate to the kill_list, or have been cleaned and should be + * moved to the clean_list. + * For fastregs, they will be dynamically allocated, and + * will be destroyed by the unmap function. + */ + if (!list_empty(&unmap_list)) { + ncleaned = rds_iw_unmap_fastreg_list(pool, &unmap_list, &kill_list); + /* If we've been asked to destroy all MRs, move those + * that were simply cleaned to the kill list */ + if (free_all) + list_splice_init(&unmap_list, &kill_list); + } + + /* Destroy any MRs that are past their best before date */ + list_for_each_entry_safe(ibmr, next, &kill_list, mapping.m_list) { + rds_iw_stats_inc(s_iw_rdma_mr_free); + list_del(&ibmr->mapping.m_list); + rds_iw_destroy_fastreg(pool, ibmr); + kfree(ibmr); + nfreed++; + } + + /* Anything that remains are laundered ibmrs, which we can add + * back to the clean list. */ + if (!list_empty(&unmap_list)) { + spin_lock_irqsave(&pool->list_lock, flags); + list_splice(&unmap_list, &pool->clean_list); + spin_unlock_irqrestore(&pool->list_lock, flags); + } + + atomic_sub(ncleaned, &pool->dirty_count); + atomic_sub(nfreed, &pool->item_count); + + mutex_unlock(&pool->flush_lock); + return ret; +} + +static void rds_iw_mr_pool_flush_worker(struct work_struct *work) +{ + struct rds_iw_mr_pool *pool = container_of(work, struct rds_iw_mr_pool, flush_worker); + + rds_iw_flush_mr_pool(pool, 0); +} + +void rds_iw_free_mr(void *trans_private, int invalidate) +{ + struct rds_iw_mr *ibmr = trans_private; + struct rds_iw_mr_pool *pool = ibmr->device->mr_pool; + + rdsdebug("RDS/IW: free_mr nents %u\n", ibmr->mapping.m_sg.len); + if (!pool) + return; + + /* Return it to the pool's free list */ + rds_iw_free_fastreg(pool, ibmr); + + /* If we've pinned too many pages, request a flush */ + if (atomic_read(&pool->free_pinned) >= pool->max_free_pinned + || atomic_read(&pool->dirty_count) >= pool->max_items / 10) + queue_work(rds_wq, &pool->flush_worker); + + if (invalidate) { + if (likely(!in_interrupt())) { + rds_iw_flush_mr_pool(pool, 0); + } else { + /* We get here if the user created a MR marked + * as use_once and invalidate at the same time. */ + queue_work(rds_wq, &pool->flush_worker); + } + } +} + +void rds_iw_flush_mrs(void) +{ + struct rds_iw_device *rds_iwdev; + + list_for_each_entry(rds_iwdev, &rds_iw_devices, list) { + struct rds_iw_mr_pool *pool = rds_iwdev->mr_pool; + + if (pool) + rds_iw_flush_mr_pool(pool, 0); + } +} + +void *rds_iw_get_mr(struct scatterlist *sg, unsigned long nents, + struct rds_sock *rs, u32 *key_ret) +{ + struct rds_iw_device *rds_iwdev; + struct rds_iw_mr *ibmr = NULL; + struct rdma_cm_id *cm_id; + int ret; + + ret = rds_iw_get_device(rs, &rds_iwdev, &cm_id); + if (ret || !cm_id) { + ret = -ENODEV; + goto out; + } + + if (!rds_iwdev->mr_pool) { + ret = -ENODEV; + goto out; + } + + ibmr = rds_iw_alloc_mr(rds_iwdev); + if (IS_ERR(ibmr)) + return ibmr; + + ibmr->cm_id = cm_id; + ibmr->device = rds_iwdev; + + ret = rds_iw_map_fastreg(rds_iwdev->mr_pool, ibmr, sg, nents); + if (ret == 0) + *key_ret = ibmr->mr->rkey; + else + printk(KERN_WARNING "RDS/IW: failed to map mr (errno=%d)\n", ret); + +out: + if (ret) { + if (ibmr) + rds_iw_free_mr(ibmr, 0); + ibmr = ERR_PTR(ret); + } + return ibmr; +} + +/* + * iWARP fastreg handling + * + * The life cycle of a fastreg registration is a bit different from + * FMRs. + * The idea behind fastreg is to have one MR, to which we bind different + * mappings over time. To avoid stalling on the expensive map and invalidate + * operations, these operations are pipelined on the same send queue on + * which we want to send the message containing the r_key. + * + * This creates a bit of a problem for us, as we do not have the destination + * IP in GET_MR, so the connection must be setup prior to the GET_MR call for + * RDMA to be correctly setup. If a fastreg request is present, rds_iw_xmit + * will try to queue a LOCAL_INV (if needed) and a FAST_REG_MR work request + * before queuing the SEND. When completions for these arrive, they are + * dispatched to the MR has a bit set showing that RDMa can be performed. + * + * There is another interesting aspect that's related to invalidation. + * The application can request that a mapping is invalidated in FREE_MR. + * The expectation there is that this invalidation step includes ALL + * PREVIOUSLY FREED MRs. + */ +static int rds_iw_init_fastreg(struct rds_iw_mr_pool *pool, + struct rds_iw_mr *ibmr) +{ + struct rds_iw_device *rds_iwdev = pool->device; + struct ib_fast_reg_page_list *page_list = NULL; + struct ib_mr *mr; + int err; + + mr = ib_alloc_fast_reg_mr(rds_iwdev->pd, pool->max_message_size); + if (IS_ERR(mr)) { + err = PTR_ERR(mr); + + printk(KERN_WARNING "RDS/IW: ib_alloc_fast_reg_mr failed (err=%d)\n", err); + return err; + } + + /* FIXME - this is overkill, but mapping->m_sg.dma_len/mapping->m_sg.dma_npages + * is not filled in. + */ + page_list = ib_alloc_fast_reg_page_list(rds_iwdev->dev, pool->max_message_size); + if (IS_ERR(page_list)) { + err = PTR_ERR(page_list); + + printk(KERN_WARNING "RDS/IW: ib_alloc_fast_reg_page_list failed (err=%d)\n", err); + ib_dereg_mr(mr); + return err; + } + + ibmr->page_list = page_list; + ibmr->mr = mr; + return 0; +} + +static int rds_iw_rdma_build_fastreg(struct rds_iw_mapping *mapping) +{ + struct rds_iw_mr *ibmr = mapping->m_mr; + struct ib_send_wr f_wr, *failed_wr; + int ret; + + /* + * Perform a WR for the fast_reg_mr. Each individual page + * in the sg list is added to the fast reg page list and placed + * inside the fast_reg_mr WR. The key used is a rolling 8bit + * counter, which should guarantee uniqueness. + */ + ib_update_fast_reg_key(ibmr->mr, ibmr->remap_count++); + mapping->m_rkey = ibmr->mr->rkey; + + memset(&f_wr, 0, sizeof(f_wr)); + f_wr.wr_id = RDS_IW_FAST_REG_WR_ID; + f_wr.opcode = IB_WR_FAST_REG_MR; + f_wr.wr.fast_reg.length = mapping->m_sg.bytes; + f_wr.wr.fast_reg.rkey = mapping->m_rkey; + f_wr.wr.fast_reg.page_list = ibmr->page_list; + f_wr.wr.fast_reg.page_list_len = mapping->m_sg.dma_len; + f_wr.wr.fast_reg.page_shift = ibmr->device->page_shift; + f_wr.wr.fast_reg.access_flags = IB_ACCESS_LOCAL_WRITE | + IB_ACCESS_REMOTE_READ | + IB_ACCESS_REMOTE_WRITE; + f_wr.wr.fast_reg.iova_start = 0; + f_wr.send_flags = IB_SEND_SIGNALED; + + failed_wr = &f_wr; + ret = ib_post_send(ibmr->cm_id->qp, &f_wr, &failed_wr); + BUG_ON(failed_wr != &f_wr); + if (ret && printk_ratelimit()) + printk(KERN_WARNING "RDS/IW: %s:%d ib_post_send returned %d\n", + __func__, __LINE__, ret); + return ret; +} + +static int rds_iw_rdma_fastreg_inv(struct rds_iw_mr *ibmr) +{ + struct ib_send_wr s_wr, *failed_wr; + int ret = 0; + + if (!ibmr->cm_id->qp || !ibmr->mr) + goto out; + + memset(&s_wr, 0, sizeof(s_wr)); + s_wr.wr_id = RDS_IW_LOCAL_INV_WR_ID; + s_wr.opcode = IB_WR_LOCAL_INV; + s_wr.ex.invalidate_rkey = ibmr->mr->rkey; + s_wr.send_flags = IB_SEND_SIGNALED; + + failed_wr = &s_wr; + ret = ib_post_send(ibmr->cm_id->qp, &s_wr, &failed_wr); + if (ret && printk_ratelimit()) { + printk(KERN_WARNING "RDS/IW: %s:%d ib_post_send returned %d\n", + __func__, __LINE__, ret); + goto out; + } +out: + return ret; +} + +static int rds_iw_map_fastreg(struct rds_iw_mr_pool *pool, + struct rds_iw_mr *ibmr, + struct scatterlist *sg, + unsigned int sg_len) +{ + struct rds_iw_device *rds_iwdev = pool->device; + struct rds_iw_mapping *mapping = &ibmr->mapping; + u64 *dma_pages; + int i, ret = 0; + + rds_iw_set_scatterlist(&mapping->m_sg, sg, sg_len); + + dma_pages = rds_iw_map_scatterlist(rds_iwdev, + &mapping->m_sg, + rds_iwdev->page_shift); + if (IS_ERR(dma_pages)) { + ret = PTR_ERR(dma_pages); + dma_pages = NULL; + goto out; + } + + if (mapping->m_sg.dma_len > pool->max_message_size) { + ret = -EMSGSIZE; + goto out; + } + + for (i = 0; i < mapping->m_sg.dma_npages; ++i) + ibmr->page_list->page_list[i] = dma_pages[i]; + + ret = rds_iw_rdma_build_fastreg(mapping); + if (ret) + goto out; + + rds_iw_stats_inc(s_iw_rdma_mr_used); + +out: + kfree(dma_pages); + + return ret; +} + +/* + * "Free" a fastreg MR. + */ +static void rds_iw_free_fastreg(struct rds_iw_mr_pool *pool, + struct rds_iw_mr *ibmr) +{ + unsigned long flags; + int ret; + + if (!ibmr->mapping.m_sg.dma_len) + return; + + ret = rds_iw_rdma_fastreg_inv(ibmr); + if (ret) + return; + + /* Try to post the LOCAL_INV WR to the queue. */ + spin_lock_irqsave(&pool->list_lock, flags); + + list_add_tail(&ibmr->mapping.m_list, &pool->dirty_list); + atomic_add(ibmr->mapping.m_sg.len, &pool->free_pinned); + atomic_inc(&pool->dirty_count); + + spin_unlock_irqrestore(&pool->list_lock, flags); +} + +static unsigned int rds_iw_unmap_fastreg_list(struct rds_iw_mr_pool *pool, + struct list_head *unmap_list, + struct list_head *kill_list) +{ + struct rds_iw_mapping *mapping, *next; + unsigned int ncleaned = 0; + LIST_HEAD(laundered); + + /* Batched invalidation of fastreg MRs. + * Why do we do it this way, even though we could pipeline unmap + * and remap? The reason is the application semantics - when the + * application requests an invalidation of MRs, it expects all + * previously released R_Keys to become invalid. + * + * If we implement MR reuse naively, we risk memory corruption + * (this has actually been observed). So the default behavior + * requires that a MR goes through an explicit unmap operation before + * we can reuse it again. + * + * We could probably improve on this a little, by allowing immediate + * reuse of a MR on the same socket (eg you could add small + * cache of unused MRs to strct rds_socket - GET_MR could grab one + * of these without requiring an explicit invalidate). + */ + while (!list_empty(unmap_list)) { + unsigned long flags; + + spin_lock_irqsave(&pool->list_lock, flags); + list_for_each_entry_safe(mapping, next, unmap_list, m_list) { + list_move(&mapping->m_list, &laundered); + ncleaned++; + } + spin_unlock_irqrestore(&pool->list_lock, flags); + } + + /* Move all laundered mappings back to the unmap list. + * We do not kill any WRs right now - it doesn't seem the + * fastreg API has a max_remap limit. */ + list_splice_init(&laundered, unmap_list); + + return ncleaned; +} + +static void rds_iw_destroy_fastreg(struct rds_iw_mr_pool *pool, + struct rds_iw_mr *ibmr) +{ + if (ibmr->page_list) + ib_free_fast_reg_page_list(ibmr->page_list); + if (ibmr->mr) + ib_dereg_mr(ibmr->mr); +} diff --git a/net/rds/iw_recv.c b/net/rds/iw_recv.c new file mode 100644 index 0000000..a1931f0 --- /dev/null +++ b/net/rds/iw_recv.c @@ -0,0 +1,869 @@ +/* + * Copyright (c) 2006 Oracle. All rights reserved. + * + * This software is available to you under a choice of one of two + * licenses. You may choose to be licensed under the terms of the GNU + * General Public License (GPL) Version 2, available from the file + * COPYING in the main directory of this source tree, or the + * OpenIB.org BSD license below: + * + * 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 + * copyright notice, this list of conditions and the following + * disclaimer in the documentation and/or other materials + * provided with the distribution. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + * + */ +#include <linux/kernel.h> +#include <linux/pci.h> +#include <linux/dma-mapping.h> +#include <rdma/rdma_cm.h> + +#include "rds.h" +#include "iw.h" + +static struct kmem_cache *rds_iw_incoming_slab; +static struct kmem_cache *rds_iw_frag_slab; +static atomic_t rds_iw_allocation = ATOMIC_INIT(0); + +static void rds_iw_frag_drop_page(struct rds_page_frag *frag) +{ + rdsdebug("frag %p page %p\n", frag, frag->f_page); + __free_page(frag->f_page); + frag->f_page = NULL; +} + +static void rds_iw_frag_free(struct rds_page_frag *frag) +{ + rdsdebug("frag %p page %p\n", frag, frag->f_page); + BUG_ON(frag->f_page != NULL); + kmem_cache_free(rds_iw_frag_slab, frag); +} + +/* + * We map a page at a time. Its fragments are posted in order. This + * is called in fragment order as the fragments get send completion events. + * Only the last frag in the page performs the unmapping. + * + * It's OK for ring cleanup to call this in whatever order it likes because + * DMA is not in flight and so we can unmap while other ring entries still + * hold page references in their frags. + */ +static void rds_iw_recv_unmap_page(struct rds_iw_connection *ic, + struct rds_iw_recv_work *recv) +{ + struct rds_page_frag *frag = recv->r_frag; + + rdsdebug("recv %p frag %p page %p\n", recv, frag, frag->f_page); + if (frag->f_mapped) + ib_dma_unmap_page(ic->i_cm_id->device, + frag->f_mapped, + RDS_FRAG_SIZE, DMA_FROM_DEVICE); + frag->f_mapped = 0; +} + +void rds_iw_recv_init_ring(struct rds_iw_connection *ic) +{ + struct rds_iw_recv_work *recv; + u32 i; + + for (i = 0, recv = ic->i_recvs; i < ic->i_recv_ring.w_nr; i++, recv++) { + struct ib_sge *sge; + + recv->r_iwinc = NULL; + recv->r_frag = NULL; + + recv->r_wr.next = NULL; + recv->r_wr.wr_id = i; + recv->r_wr.sg_list = recv->r_sge; + recv->r_wr.num_sge = RDS_IW_RECV_SGE; + + sge = rds_iw_data_sge(ic, recv->r_sge); + sge->addr = 0; + sge->length = RDS_FRAG_SIZE; + sge->lkey = 0; + + sge = rds_iw_header_sge(ic, recv->r_sge); + sge->addr = ic->i_recv_hdrs_dma + (i * sizeof(struct rds_header)); + sge->length = sizeof(struct rds_header); + sge->lkey = 0; + } +} + +static void rds_iw_recv_clear_one(struct rds_iw_connection *ic, + struct rds_iw_recv_work *recv) +{ + if (recv->r_iwinc) { + rds_inc_put(&recv->r_iwinc->ii_inc); + recv->r_iwinc = NULL; + } + if (recv->r_frag) { + rds_iw_recv_unmap_page(ic, recv); + if (recv->r_frag->f_page) + rds_iw_frag_drop_page(recv->r_frag); + rds_iw_frag_free(recv->r_frag); + recv->r_frag = NULL; + } +} + +void rds_iw_recv_clear_ring(struct rds_iw_connection *ic) +{ + u32 i; + + for (i = 0; i < ic->i_recv_ring.w_nr; i++) + rds_iw_recv_clear_one(ic, &ic->i_recvs[i]); + + if (ic->i_frag.f_page) + rds_iw_frag_drop_page(&ic->i_frag); +} + +static int rds_iw_recv_refill_one(struct rds_connection *conn, + struct rds_iw_recv_work *recv, + gfp_t kptr_gfp, gfp_t page_gfp) +{ + struct rds_iw_connection *ic = conn->c_transport_data; + dma_addr_t dma_addr; + struct ib_sge *sge; + int ret = -ENOMEM; + + if (recv->r_iwinc == NULL) { + if (atomic_read(&rds_iw_allocation) >= rds_iw_sysctl_max_recv_allocation) { + rds_iw_stats_inc(s_iw_rx_alloc_limit); + goto out; + } + recv->r_iwinc = kmem_cache_alloc(rds_iw_incoming_slab, + kptr_gfp); + if (recv->r_iwinc == NULL) + goto out; + atomic_inc(&rds_iw_allocation); + INIT_LIST_HEAD(&recv->r_iwinc->ii_frags); + rds_inc_init(&recv->r_iwinc->ii_inc, conn, conn->c_faddr); + } + + if (recv->r_frag == NULL) { + recv->r_frag = kmem_cache_alloc(rds_iw_frag_slab, kptr_gfp); + if (recv->r_frag == NULL) + goto out; + INIT_LIST_HEAD(&recv->r_frag->f_item); + recv->r_frag->f_page = NULL; + } + + if (ic->i_frag.f_page == NULL) { + ic->i_frag.f_page = alloc_page(page_gfp); + if (ic->i_frag.f_page == NULL) + goto out; + ic->i_frag.f_offset = 0; + } + + dma_addr = ib_dma_map_page(ic->i_cm_id->device, + ic->i_frag.f_page, + ic->i_frag.f_offset, + RDS_FRAG_SIZE, + DMA_FROM_DEVICE); + if (ib_dma_mapping_error(ic->i_cm_id->device, dma_addr)) + goto out; + + /* + * Once we get the RDS_PAGE_LAST_OFF frag then rds_iw_frag_unmap() + * must be called on this recv. This happens as completions hit + * in order or on connection shutdown. + */ + recv->r_frag->f_page = ic->i_frag.f_page; + recv->r_frag->f_offset = ic->i_frag.f_offset; + recv->r_frag->f_mapped = dma_addr; + + sge = rds_iw_data_sge(ic, recv->r_sge); + sge->addr = dma_addr; + sge->length = RDS_FRAG_SIZE; + + sge = rds_iw_header_sge(ic, recv->r_sge); + sge->addr = ic->i_recv_hdrs_dma + (recv - ic->i_recvs) * sizeof(struct rds_header); + sge->length = sizeof(struct rds_header); + + get_page(recv->r_frag->f_page); + + if (ic->i_frag.f_offset < RDS_PAGE_LAST_OFF) { + ic->i_frag.f_offset += RDS_FRAG_SIZE; + } else { + put_page(ic->i_frag.f_page); + ic->i_frag.f_page = NULL; + ic->i_frag.f_offset = 0; + } + + ret = 0; +out: + return ret; +} + +/* + * This tries to allocate and post unused work requests after making sure that + * they have all the allocations they need to queue received fragments into + * sockets. The i_recv_mutex is held here so that ring_alloc and _unalloc + * pairs don't go unmatched. + * + * -1 is returned if posting fails due to temporary resource exhaustion. + */ +int rds_iw_recv_refill(struct rds_connection *conn, gfp_t kptr_gfp, + gfp_t page_gfp, int prefill) +{ + struct rds_iw_connection *ic = conn->c_transport_data; + struct rds_iw_recv_work *recv; + struct ib_recv_wr *failed_wr; + unsigned int posted = 0; + int ret = 0; + u32 pos; + + while ((prefill || rds_conn_up(conn)) + && rds_iw_ring_alloc(&ic->i_recv_ring, 1, &pos)) { + if (pos >= ic->i_recv_ring.w_nr) { + printk(KERN_NOTICE "Argh - ring alloc returned pos=%u\n", + pos); + ret = -EINVAL; + break; + } + + recv = &ic->i_recvs[pos]; + ret = rds_iw_recv_refill_one(conn, recv, kptr_gfp, page_gfp); + if (ret) { + ret = -1; + break; + } + + /* XXX when can this fail? */ + ret = ib_post_recv(ic->i_cm_id->qp, &recv->r_wr, &failed_wr); + rdsdebug("recv %p iwinc %p page %p addr %lu ret %d\n", recv, + recv->r_iwinc, recv->r_frag->f_page, + (long) recv->r_frag->f_mapped, ret); + if (ret) { + rds_iw_conn_error(conn, "recv post on " + "%pI4 returned %d, disconnecting and " + "reconnecting\n", &conn->c_faddr, + ret); + ret = -1; + break; + } + + posted++; + } + + /* We're doing flow control - update the window. */ + if (ic->i_flowctl && posted) + rds_iw_advertise_credits(conn, posted); + + if (ret) + rds_iw_ring_unalloc(&ic->i_recv_ring, 1); + return ret; +} + +void rds_iw_inc_purge(struct rds_incoming *inc) +{ + struct rds_iw_incoming *iwinc; + struct rds_page_frag *frag; + struct rds_page_frag *pos; + + iwinc = container_of(inc, struct rds_iw_incoming, ii_inc); + rdsdebug("purging iwinc %p inc %p\n", iwinc, inc); + + list_for_each_entry_safe(frag, pos, &iwinc->ii_frags, f_item) { + list_del_init(&frag->f_item); + rds_iw_frag_drop_page(frag); + rds_iw_frag_free(frag); + } +} + +void rds_iw_inc_free(struct rds_incoming *inc) +{ + struct rds_iw_incoming *iwinc; + + iwinc = container_of(inc, struct rds_iw_incoming, ii_inc); + + rds_iw_inc_purge(inc); + rdsdebug("freeing iwinc %p inc %p\n", iwinc, inc); + BUG_ON(!list_empty(&iwinc->ii_frags)); + kmem_cache_free(rds_iw_incoming_slab, iwinc); + atomic_dec(&rds_iw_allocation); + BUG_ON(atomic_read(&rds_iw_allocation) < 0); +} + +int rds_iw_inc_copy_to_user(struct rds_incoming *inc, struct iovec *first_iov, + size_t size) +{ + struct rds_iw_incoming *iwinc; + struct rds_page_frag *frag; + struct iovec *iov = first_iov; + unsigned long to_copy; + unsigned long frag_off = 0; + unsigned long iov_off = 0; + int copied = 0; + int ret; + u32 len; + + iwinc = container_of(inc, struct rds_iw_incoming, ii_inc); + frag = list_entry(iwinc->ii_frags.next, struct rds_page_frag, f_item); + len = be32_to_cpu(inc->i_hdr.h_len); + + while (copied < size && copied < len) { + if (frag_off == RDS_FRAG_SIZE) { + frag = list_entry(frag->f_item.next, + struct rds_page_frag, f_item); + frag_off = 0; + } + while (iov_off == iov->iov_len) { + iov_off = 0; + iov++; + } + + to_copy = min(iov->iov_len - iov_off, RDS_FRAG_SIZE - frag_off); + to_copy = min_t(size_t, to_copy, size - copied); + to_copy = min_t(unsigned long, to_copy, len - copied); + + rdsdebug("%lu bytes to user [%p, %zu] + %lu from frag " + "[%p, %lu] + %lu\n", + to_copy, iov->iov_base, iov->iov_len, iov_off, + frag->f_page, frag->f_offset, frag_off); + + /* XXX needs + offset for multiple recvs per page */ + ret = rds_page_copy_to_user(frag->f_page, + frag->f_offset + frag_off, + iov->iov_base + iov_off, + to_copy); + if (ret) { + copied = ret; + break; + } + + iov_off += to_copy; + frag_off += to_copy; + copied += to_copy; + } + + return copied; +} + +/* ic starts out kzalloc()ed */ +void rds_iw_recv_init_ack(struct rds_iw_connection *ic) +{ + struct ib_send_wr *wr = &ic->i_ack_wr; + struct ib_sge *sge = &ic->i_ack_sge; + + sge->addr = ic->i_ack_dma; + sge->length = sizeof(struct rds_header); + sge->lkey = rds_iw_local_dma_lkey(ic); + + wr->sg_list = sge; + wr->num_sge = 1; + wr->opcode = IB_WR_SEND; + wr->wr_id = RDS_IW_ACK_WR_ID; + wr->send_flags = IB_SEND_SIGNALED | IB_SEND_SOLICITED; +} + +/* + * You'd think that with reliable IB connections you wouldn't need to ack + * messages that have been received. The problem is that IB hardware generates + * an ack message before it has DMAed the message into memory. This creates a + * potential message loss if the HCA is disabled for any reason between when it + * sends the ack and before the message is DMAed and processed. This is only a + * potential issue if another HCA is available for fail-over. + * + * When the remote host receives our ack they'll free the sent message from + * their send queue. To decrease the latency of this we always send an ack + * immediately after we've received messages. + * + * For simplicity, we only have one ack in flight at a time. This puts + * pressure on senders to have deep enough send queues to absorb the latency of + * a single ack frame being in flight. This might not be good enough. + * + * This is implemented by have a long-lived send_wr and sge which point to a + * statically allocated ack frame. This ack wr does not fall under the ring + * accounting that the tx and rx wrs do. The QP attribute specifically makes + * room for it beyond the ring size. Send completion notices its special + * wr_id and avoids working with the ring in that case. + */ +static void rds_iw_set_ack(struct rds_iw_connection *ic, u64 seq, + int ack_required) +{ + rds_iw_set_64bit(&ic->i_ack_next, seq); + if (ack_required) { + smp_mb__before_clear_bit(); + set_bit(IB_ACK_REQUESTED, &ic->i_ack_flags); + } +} + +static u64 rds_iw_get_ack(struct rds_iw_connection *ic) +{ + clear_bit(IB_ACK_REQUESTED, &ic->i_ack_flags); + smp_mb__after_clear_bit(); + + return ic->i_ack_next; +} + +static void rds_iw_send_ack(struct rds_iw_connection *ic, unsigned int adv_credits) +{ + struct rds_header *hdr = ic->i_ack; + struct ib_send_wr *failed_wr; + u64 seq; + int ret; + + seq = rds_iw_get_ack(ic); + + rdsdebug("send_ack: ic %p ack %llu\n", ic, (unsigned long long) seq); + rds_message_populate_header(hdr, 0, 0, 0); + hdr->h_ack = cpu_to_be64(seq); + hdr->h_credit = adv_credits; + rds_message_make_checksum(hdr); + ic->i_ack_queued = jiffies; + + ret = ib_post_send(ic->i_cm_id->qp, &ic->i_ack_wr, &failed_wr); + if (unlikely(ret)) { + /* Failed to send. Release the WR, and + * force another ACK. + */ + clear_bit(IB_ACK_IN_FLIGHT, &ic->i_ack_flags); + set_bit(IB_ACK_REQUESTED, &ic->i_ack_flags); + + rds_iw_stats_inc(s_iw_ack_send_failure); + /* Need to finesse this later. */ + BUG(); + } else + rds_iw_stats_inc(s_iw_ack_sent); +} + +/* + * There are 3 ways of getting acknowledgements to the peer: + * 1. We call rds_iw_attempt_ack from the recv completion handler + * to send an ACK-only frame. + * However, there can be only one such frame in the send queue + * at any time, so we may have to postpone it. + * 2. When another (data) packet is transmitted while there's + * an ACK in the queue, we piggyback the ACK sequence number + * on the data packet. + * 3. If the ACK WR is done sending, we get called from the + * send queue completion handler, and check whether there's + * another ACK pending (postponed because the WR was on the + * queue). If so, we transmit it. + * + * We maintain 2 variables: + * - i_ack_flags, which keeps track of whether the ACK WR + * is currently in the send queue or not (IB_ACK_IN_FLIGHT) + * - i_ack_next, which is the last sequence number we received + * + * Potentially, send queue and receive queue handlers can run concurrently. + * + * Reconnecting complicates this picture just slightly. When we + * reconnect, we may be seeing duplicate packets. The peer + * is retransmitting them, because it hasn't seen an ACK for + * them. It is important that we ACK these. + * + * ACK mitigation adds a header flag "ACK_REQUIRED"; any packet with + * this flag set *MUST* be acknowledged immediately. + */ + +/* + * When we get here, we're called from the recv queue handler. + * Check whether we ought to transmit an ACK. + */ +void rds_iw_attempt_ack(struct rds_iw_connection *ic) +{ + unsigned int adv_credits; + + if (!test_bit(IB_ACK_REQUESTED, &ic->i_ack_flags)) + return; + + if (test_and_set_bit(IB_ACK_IN_FLIGHT, &ic->i_ack_flags)) { + rds_iw_stats_inc(s_iw_ack_send_delayed); + return; + } + + /* Can we get a send credit? */ + if (!rds_iw_send_grab_credits(ic, 1, &adv_credits, 0)) { + rds_iw_stats_inc(s_iw_tx_throttle); + clear_bit(IB_ACK_IN_FLIGHT, &ic->i_ack_flags); + return; + } + + clear_bit(IB_ACK_REQUESTED, &ic->i_ack_flags); + rds_iw_send_ack(ic, adv_credits); +} + +/* + * We get here from the send completion handler, when the + * adapter tells us the ACK frame was sent. + */ +void rds_iw_ack_send_complete(struct rds_iw_connection *ic) +{ + clear_bit(IB_ACK_IN_FLIGHT, &ic->i_ack_flags); + rds_iw_attempt_ack(ic); +} + +/* + * This is called by the regular xmit code when it wants to piggyback + * an ACK on an outgoing frame. + */ +u64 rds_iw_piggyb_ack(struct rds_iw_connection *ic) +{ + if (test_and_clear_bit(IB_ACK_REQUESTED, &ic->i_ack_flags)) + rds_iw_stats_inc(s_iw_ack_send_piggybacked); + return rds_iw_get_ack(ic); +} + +/* + * It's kind of lame that we're copying from the posted receive pages into + * long-lived bitmaps. We could have posted the bitmaps and rdma written into + * them. But receiving new congestion bitmaps should be a *rare* event, so + * hopefully we won't need to invest that complexity in making it more + * efficient. By copying we can share a simpler core with TCP which has to + * copy. + */ +static void rds_iw_cong_recv(struct rds_connection *conn, + struct rds_iw_incoming *iwinc) +{ + struct rds_cong_map *map; + unsigned int map_off; + unsigned int map_page; + struct rds_page_frag *frag; + unsigned long frag_off; + unsigned long to_copy; + unsigned long copied; + uint64_t uncongested = 0; + void *addr; + + /* catch completely corrupt packets */ + if (be32_to_cpu(iwinc->ii_inc.i_hdr.h_len) != RDS_CONG_MAP_BYTES) + return; + + map = conn->c_fcong; + map_page = 0; + map_off = 0; + + frag = list_entry(iwinc->ii_frags.next, struct rds_page_frag, f_item); + frag_off = 0; + + copied = 0; + + while (copied < RDS_CONG_MAP_BYTES) { + uint64_t *src, *dst; + unsigned int k; + + to_copy = min(RDS_FRAG_SIZE - frag_off, PAGE_SIZE - map_off); + BUG_ON(to_copy & 7); /* Must be 64bit aligned. */ + + addr = kmap_atomic(frag->f_page, KM_SOFTIRQ0); + + src = addr + frag_off; + dst = (void *)map->m_page_addrs[map_page] + map_off; + for (k = 0; k < to_copy; k += 8) { + /* Record ports that became uncongested, ie + * bits that changed from 0 to 1. */ + uncongested |= ~(*src) & *dst; + *dst++ = *src++; + } + kunmap_atomic(addr, KM_SOFTIRQ0); + + copied += to_copy; + + map_off += to_copy; + if (map_off == PAGE_SIZE) { + map_off = 0; + map_page++; + } + + frag_off += to_copy; + if (frag_off == RDS_FRAG_SIZE) { + frag = list_entry(frag->f_item.next, + struct rds_page_frag, f_item); + frag_off = 0; + } + } + + /* the congestion map is in little endian order */ + uncongested = le64_to_cpu(uncongested); + + rds_cong_map_updated(map, uncongested); +} + +/* + * Rings are posted with all the allocations they'll need to queue the + * incoming message to the receiving socket so this can't fail. + * All fragments start with a header, so we can make sure we're not receiving + * garbage, and we can tell a small 8 byte fragment from an ACK frame. + */ +struct rds_iw_ack_state { + u64 ack_next; + u64 ack_recv; + unsigned int ack_required:1; + unsigned int ack_next_valid:1; + unsigned int ack_recv_valid:1; +}; + +static void rds_iw_process_recv(struct rds_connection *conn, + struct rds_iw_recv_work *recv, u32 byte_len, + struct rds_iw_ack_state *state) +{ + struct rds_iw_connection *ic = conn->c_transport_data; + struct rds_iw_incoming *iwinc = ic->i_iwinc; + struct rds_header *ihdr, *hdr; + + /* XXX shut down the connection if port 0,0 are seen? */ + + rdsdebug("ic %p iwinc %p recv %p byte len %u\n", ic, iwinc, recv, + byte_len); + + if (byte_len < sizeof(struct rds_header)) { + rds_iw_conn_error(conn, "incoming message " + "from %pI4 didn't inclue a " + "header, disconnecting and " + "reconnecting\n", + &conn->c_faddr); + return; + } + byte_len -= sizeof(struct rds_header); + + ihdr = &ic->i_recv_hdrs[recv - ic->i_recvs]; + + /* Validate the checksum. */ + if (!rds_message_verify_checksum(ihdr)) { + rds_iw_conn_error(conn, "incoming message " + "from %pI4 has corrupted header - " + "forcing a reconnect\n", + &conn->c_faddr); + rds_stats_inc(s_recv_drop_bad_checksum); + return; + } + + /* Process the ACK sequence which comes with every packet */ + state->ack_recv = be64_to_cpu(ihdr->h_ack); + state->ack_recv_valid = 1; + + /* Process the credits update if there was one */ + if (ihdr->h_credit) + rds_iw_send_add_credits(conn, ihdr->h_credit); + + if (ihdr->h_sport == 0 && ihdr->h_dport == 0 && byte_len == 0) { + /* This is an ACK-only packet. The fact that it gets + * special treatment here is that historically, ACKs + * were rather special beasts. + */ + rds_iw_stats_inc(s_iw_ack_received); + + /* + * Usually the frags make their way on to incs and are then freed as + * the inc is freed. We don't go that route, so we have to drop the + * page ref ourselves. We can't just leave the page on the recv + * because that confuses the dma mapping of pages and each recv's use + * of a partial page. We can leave the frag, though, it will be + * reused. + * + * FIXME: Fold this into the code path below. + */ + rds_iw_frag_drop_page(recv->r_frag); + return; + } + + /* + * If we don't already have an inc on the connection then this + * fragment has a header and starts a message.. copy its header + * into the inc and save the inc so we can hang upcoming fragments + * off its list. + */ + if (iwinc == NULL) { + iwinc = recv->r_iwinc; + recv->r_iwinc = NULL; + ic->i_iwinc = iwinc; + + hdr = &iwinc->ii_inc.i_hdr; + memcpy(hdr, ihdr, sizeof(*hdr)); + ic->i_recv_data_rem = be32_to_cpu(hdr->h_len); + + rdsdebug("ic %p iwinc %p rem %u flag 0x%x\n", ic, iwinc, + ic->i_recv_data_rem, hdr->h_flags); + } else { + hdr = &iwinc->ii_inc.i_hdr; + /* We can't just use memcmp here; fragments of a + * single message may carry different ACKs */ + if (hdr->h_sequence != ihdr->h_sequence + || hdr->h_len != ihdr->h_len + || hdr->h_sport != ihdr->h_sport + || hdr->h_dport != ihdr->h_dport) { + rds_iw_conn_error(conn, + "fragment header mismatch; forcing reconnect\n"); + return; + } + } + + list_add_tail(&recv->r_frag->f_item, &iwinc->ii_frags); + recv->r_frag = NULL; + + if (ic->i_recv_data_rem > RDS_FRAG_SIZE) + ic->i_recv_data_rem -= RDS_FRAG_SIZE; + else { + ic->i_recv_data_rem = 0; + ic->i_iwinc = NULL; + + if (iwinc->ii_inc.i_hdr.h_flags == RDS_FLAG_CONG_BITMAP) + rds_iw_cong_recv(conn, iwinc); + else { + rds_recv_incoming(conn, conn->c_faddr, conn->c_laddr, + &iwinc->ii_inc, GFP_ATOMIC, + KM_SOFTIRQ0); + state->ack_next = be64_to_cpu(hdr->h_sequence); + state->ack_next_valid = 1; + } + + /* Evaluate the ACK_REQUIRED flag *after* we received + * the complete frame, and after bumping the next_rx + * sequence. */ + if (hdr->h_flags & RDS_FLAG_ACK_REQUIRED) { + rds_stats_inc(s_recv_ack_required); + state->ack_required = 1; + } + + rds_inc_put(&iwinc->ii_inc); + } +} + +/* + * Plucking the oldest entry from the ring can be done concurrently with + * the thread refilling the ring. Each ring operation is protected by + * spinlocks and the transient state of refilling doesn't change the + * recording of which entry is oldest. + * + * This relies on IB only calling one cq comp_handler for each cq so that + * there will only be one caller of rds_recv_incoming() per RDS connection. + */ +void rds_iw_recv_cq_comp_handler(struct ib_cq *cq, void *context) +{ + struct rds_connection *conn = context; + struct rds_iw_connection *ic = conn->c_transport_data; + struct ib_wc wc; + struct rds_iw_ack_state state = { 0, }; + struct rds_iw_recv_work *recv; + + rdsdebug("conn %p cq %p\n", conn, cq); + + rds_iw_stats_inc(s_iw_rx_cq_call); + + ib_req_notify_cq(cq, IB_CQ_SOLICITED); + + while (ib_poll_cq(cq, 1, &wc) > 0) { + rdsdebug("wc wr_id 0x%llx status %u byte_len %u imm_data %u\n", + (unsigned long long)wc.wr_id, wc.status, wc.byte_len, + be32_to_cpu(wc.ex.imm_data)); + rds_iw_stats_inc(s_iw_rx_cq_event); + + recv = &ic->i_recvs[rds_iw_ring_oldest(&ic->i_recv_ring)]; + + rds_iw_recv_unmap_page(ic, recv); + + /* + * Also process recvs in connecting state because it is possible + * to get a recv completion _before_ the rdmacm ESTABLISHED + * event is processed. + */ + if (rds_conn_up(conn) || rds_conn_connecting(conn)) { + /* We expect errors as the qp is drained during shutdown */ + if (wc.status == IB_WC_SUCCESS) { + rds_iw_process_recv(conn, recv, wc.byte_len, &state); + } else { + rds_iw_conn_error(conn, "recv completion on " + "%pI4 had status %u, disconnecting and " + "reconnecting\n", &conn->c_faddr, + wc.status); + } + } + + rds_iw_ring_free(&ic->i_recv_ring, 1); + } + + if (state.ack_next_valid) + rds_iw_set_ack(ic, state.ack_next, state.ack_required); + if (state.ack_recv_valid && state.ack_recv > ic->i_ack_recv) { + rds_send_drop_acked(conn, state.ack_recv, NULL); + ic->i_ack_recv = state.ack_recv; + } + if (rds_conn_up(conn)) + rds_iw_attempt_ack(ic); + + /* If we ever end up with a really empty receive ring, we're + * in deep trouble, as the sender will definitely see RNR + * timeouts. */ + if (rds_iw_ring_empty(&ic->i_recv_ring)) + rds_iw_stats_inc(s_iw_rx_ring_empty); + + /* + * If the ring is running low, then schedule the thread to refill. + */ + if (rds_iw_ring_low(&ic->i_recv_ring)) + queue_delayed_work(rds_wq, &conn->c_recv_w, 0); +} + +int rds_iw_recv(struct rds_connection *conn) +{ + struct rds_iw_connection *ic = conn->c_transport_data; + int ret = 0; + + rdsdebug("conn %p\n", conn); + + /* + * If we get a temporary posting failure in this context then + * we're really low and we want the caller to back off for a bit. + */ + mutex_lock(&ic->i_recv_mutex); + if (rds_iw_recv_refill(conn, GFP_KERNEL, GFP_HIGHUSER, 0)) + ret = -ENOMEM; + else + rds_iw_stats_inc(s_iw_rx_refill_from_thread); + mutex_unlock(&ic->i_recv_mutex); + + if (rds_conn_up(conn)) + rds_iw_attempt_ack(ic); + + return ret; +} + +int __init rds_iw_recv_init(void) +{ + struct sysinfo si; + int ret = -ENOMEM; + + /* Default to 30% of all available RAM for recv memory */ + si_meminfo(&si); + rds_iw_sysctl_max_recv_allocation = si.totalram / 3 * PAGE_SIZE / RDS_FRAG_SIZE; + + rds_iw_incoming_slab = kmem_cache_create("rds_iw_incoming", + sizeof(struct rds_iw_incoming), + 0, 0, NULL); + if (rds_iw_incoming_slab == NULL) + goto out; + + rds_iw_frag_slab = kmem_cache_create("rds_iw_frag", + sizeof(struct rds_page_frag), + 0, 0, NULL); + if (rds_iw_frag_slab == NULL) + kmem_cache_destroy(rds_iw_incoming_slab); + else + ret = 0; +out: + return ret; +} + +void rds_iw_recv_exit(void) +{ + kmem_cache_destroy(rds_iw_incoming_slab); + kmem_cache_destroy(rds_iw_frag_slab); +} diff --git a/net/rds/iw_ring.c b/net/rds/iw_ring.c new file mode 100644 index 0000000..d422d4b --- /dev/null +++ b/net/rds/iw_ring.c @@ -0,0 +1,169 @@ +/* + * Copyright (c) 2006 Oracle. All rights reserved. + * + * This software is available to you under a choice of one of two + * licenses. You may choose to be licensed under the terms of the GNU + * General Public License (GPL) Version 2, available from the file + * COPYING in the main directory of this source tree, or the + * OpenIB.org BSD license below: + * + * 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 + * copyright notice, this list of conditions and the following + * disclaimer in the documentation and/or other materials + * provided with the distribution. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + * + */ +#include <linux/kernel.h> + +#include "rds.h" +#include "iw.h" + +/* + * Locking for IB rings. + * We assume that allocation is always protected by a mutex + * in the caller (this is a valid assumption for the current + * implementation). + * + * Freeing always happens in an interrupt, and hence only + * races with allocations, but not with other free()s. + * + * The interaction between allocation and freeing is that + * the alloc code has to determine the number of free entries. + * To this end, we maintain two counters; an allocation counter + * and a free counter. Both are allowed to run freely, and wrap + * around. + * The number of used entries is always (alloc_ctr - free_ctr) % NR. + * + * The current implementation makes free_ctr atomic. When the + * caller finds an allocation fails, it should set an "alloc fail" + * bit and retry the allocation. The "alloc fail" bit essentially tells + * the CQ completion handlers to wake it up after freeing some + * more entries. + */ + +/* + * This only happens on shutdown. + */ +DECLARE_WAIT_QUEUE_HEAD(rds_iw_ring_empty_wait); + +void rds_iw_ring_init(struct rds_iw_work_ring *ring, u32 nr) +{ + memset(ring, 0, sizeof(*ring)); + ring->w_nr = nr; + rdsdebug("ring %p nr %u\n", ring, ring->w_nr); +} + +static inline u32 __rds_iw_ring_used(struct rds_iw_work_ring *ring) +{ + u32 diff; + + /* This assumes that atomic_t has at least as many bits as u32 */ + diff = ring->w_alloc_ctr - (u32) atomic_read(&ring->w_free_ctr); + BUG_ON(diff > ring->w_nr); + + return diff; +} + +void rds_iw_ring_resize(struct rds_iw_work_ring *ring, u32 nr) +{ + /* We only ever get called from the connection setup code, + * prior to creating the QP. */ + BUG_ON(__rds_iw_ring_used(ring)); + ring->w_nr = nr; +} + +static int __rds_iw_ring_empty(struct rds_iw_work_ring *ring) +{ + return __rds_iw_ring_used(ring) == 0; +} + +u32 rds_iw_ring_alloc(struct rds_iw_work_ring *ring, u32 val, u32 *pos) +{ + u32 ret = 0, avail; + + avail = ring->w_nr - __rds_iw_ring_used(ring); + + rdsdebug("ring %p val %u next %u free %u\n", ring, val, + ring->w_alloc_ptr, avail); + + if (val && avail) { + ret = min(val, avail); + *pos = ring->w_alloc_ptr; + + ring->w_alloc_ptr = (ring->w_alloc_ptr + ret) % ring->w_nr; + ring->w_alloc_ctr += ret; + } + + return ret; +} + +void rds_iw_ring_free(struct rds_iw_work_ring *ring, u32 val) +{ + ring->w_free_ptr = (ring->w_free_ptr + val) % ring->w_nr; + atomic_add(val, &ring->w_free_ctr); + + if (__rds_iw_ring_empty(ring) && + waitqueue_active(&rds_iw_ring_empty_wait)) + wake_up(&rds_iw_ring_empty_wait); +} + +void rds_iw_ring_unalloc(struct rds_iw_work_ring *ring, u32 val) +{ + ring->w_alloc_ptr = (ring->w_alloc_ptr - val) % ring->w_nr; + ring->w_alloc_ctr -= val; +} + +int rds_iw_ring_empty(struct rds_iw_work_ring *ring) +{ + return __rds_iw_ring_empty(ring); +} + +int rds_iw_ring_low(struct rds_iw_work_ring *ring) +{ + return __rds_iw_ring_used(ring) <= (ring->w_nr >> 2); +} + + +/* + * returns the oldest alloced ring entry. This will be the next one + * freed. This can't be called if there are none allocated. + */ +u32 rds_iw_ring_oldest(struct rds_iw_work_ring *ring) +{ + return ring->w_free_ptr; +} + +/* + * returns the number of completed work requests. + */ + +u32 rds_iw_ring_completed(struct rds_iw_work_ring *ring, u32 wr_id, u32 oldest) +{ + u32 ret; + + if (oldest <= (unsigned long long)wr_id) + ret = (unsigned long long)wr_id - oldest + 1; + else + ret = ring->w_nr - oldest + (unsigned long long)wr_id + 1; + + rdsdebug("ring %p ret %u wr_id %u oldest %u\n", ring, ret, + wr_id, oldest); + return ret; +} diff --git a/net/rds/iw_send.c b/net/rds/iw_send.c new file mode 100644 index 0000000..22dd38f --- /dev/null +++ b/net/rds/iw_send.c @@ -0,0 +1,975 @@ +/* + * Copyright (c) 2006 Oracle. All rights reserved. + * + * This software is available to you under a choice of one of two + * licenses. You may choose to be licensed under the terms of the GNU + * General Public License (GPL) Version 2, available from the file + * COPYING in the main directory of this source tree, or the + * OpenIB.org BSD license below: + * + * 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 + * copyright notice, this list of conditions and the following + * disclaimer in the documentation and/or other materials + * provided with the distribution. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + * + */ +#include <linux/kernel.h> +#include <linux/in.h> +#include <linux/device.h> +#include <linux/dmapool.h> + +#include "rds.h" +#include "rdma.h" +#include "iw.h" + +static void rds_iw_send_rdma_complete(struct rds_message *rm, + int wc_status) +{ + int notify_status; + + switch (wc_status) { + case IB_WC_WR_FLUSH_ERR: + return; + + case IB_WC_SUCCESS: + notify_status = RDS_RDMA_SUCCESS; + break; + + case IB_WC_REM_ACCESS_ERR: + notify_status = RDS_RDMA_REMOTE_ERROR; + break; + + default: + notify_status = RDS_RDMA_OTHER_ERROR; + break; + } + rds_rdma_send_complete(rm, notify_status); +} + +static void rds_iw_send_unmap_rdma(struct rds_iw_connection *ic, + struct rds_rdma_op *op) +{ + if (op->r_mapped) { + ib_dma_unmap_sg(ic->i_cm_id->device, + op->r_sg, op->r_nents, + op->r_write ? DMA_TO_DEVICE : DMA_FROM_DEVICE); + op->r_mapped = 0; + } +} + +static void rds_iw_send_unmap_rm(struct rds_iw_connection *ic, + struct rds_iw_send_work *send, + int wc_status) +{ + struct rds_message *rm = send->s_rm; + + rdsdebug("ic %p send %p rm %p\n", ic, send, rm); + + ib_dma_unmap_sg(ic->i_cm_id->device, + rm->m_sg, rm->m_nents, + DMA_TO_DEVICE); + + if (rm->m_rdma_op != NULL) { + rds_iw_send_unmap_rdma(ic, rm->m_rdma_op); + + /* If the user asked for a completion notification on this + * message, we can implement three different semantics: + * 1. Notify when we received the ACK on the RDS message + * that was queued with the RDMA. This provides reliable + * notification of RDMA status at the expense of a one-way + * packet delay. + * 2. Notify when the IB stack gives us the completion event for + * the RDMA operation. + * 3. Notify when the IB stack gives us the completion event for + * the accompanying RDS messages. + * Here, we implement approach #3. To implement approach #2, + * call rds_rdma_send_complete from the cq_handler. To implement #1, + * don't call rds_rdma_send_complete at all, and fall back to the notify + * handling in the ACK processing code. + * + * Note: There's no need to explicitly sync any RDMA buffers using + * ib_dma_sync_sg_for_cpu - the completion for the RDMA + * operation itself unmapped the RDMA buffers, which takes care + * of synching. + */ + rds_iw_send_rdma_complete(rm, wc_status); + + if (rm->m_rdma_op->r_write) + rds_stats_add(s_send_rdma_bytes, rm->m_rdma_op->r_bytes); + else + rds_stats_add(s_recv_rdma_bytes, rm->m_rdma_op->r_bytes); + } + + /* If anyone waited for this message to get flushed out, wake + * them up now */ + rds_message_unmapped(rm); + + rds_message_put(rm); + send->s_rm = NULL; +} + +void rds_iw_send_init_ring(struct rds_iw_connection *ic) +{ + struct rds_iw_send_work *send; + u32 i; + + for (i = 0, send = ic->i_sends; i < ic->i_send_ring.w_nr; i++, send++) { + struct ib_sge *sge; + + send->s_rm = NULL; + send->s_op = NULL; + send->s_mapping = NULL; + + send->s_wr.next = NULL; + send->s_wr.wr_id = i; + send->s_wr.sg_list = send->s_sge; + send->s_wr.num_sge = 1; + send->s_wr.opcode = IB_WR_SEND; + send->s_wr.send_flags = 0; + send->s_wr.ex.imm_data = 0; + + sge = rds_iw_data_sge(ic, send->s_sge); + sge->lkey = 0; + + sge = rds_iw_header_sge(ic, send->s_sge); + sge->addr = ic->i_send_hdrs_dma + (i * sizeof(struct rds_header)); + sge->length = sizeof(struct rds_header); + sge->lkey = 0; + + send->s_mr = ib_alloc_fast_reg_mr(ic->i_pd, fastreg_message_size); + if (IS_ERR(send->s_mr)) { + printk(KERN_WARNING "RDS/IW: ib_alloc_fast_reg_mr failed\n"); + break; + } + + send->s_page_list = ib_alloc_fast_reg_page_list( + ic->i_cm_id->device, fastreg_message_size); + if (IS_ERR(send->s_page_list)) { + printk(KERN_WARNING "RDS/IW: ib_alloc_fast_reg_page_list failed\n"); + break; + } + } +} + +void rds_iw_send_clear_ring(struct rds_iw_connection *ic) +{ + struct rds_iw_send_work *send; + u32 i; + + for (i = 0, send = ic->i_sends; i < ic->i_send_ring.w_nr; i++, send++) { + BUG_ON(!send->s_mr); + ib_dereg_mr(send->s_mr); + BUG_ON(!send->s_page_list); + ib_free_fast_reg_page_list(send->s_page_list); + if (send->s_wr.opcode == 0xdead) + continue; + if (send->s_rm) + rds_iw_send_unmap_rm(ic, send, IB_WC_WR_FLUSH_ERR); + if (send->s_op) + rds_iw_send_unmap_rdma(ic, send->s_op); + } +} + +/* + * The _oldest/_free ring operations here race cleanly with the alloc/unalloc + * operations performed in the send path. As the sender allocs and potentially + * unallocs the next free entry in the ring it doesn't alter which is + * the next to be freed, which is what this is concerned with. + */ +void rds_iw_send_cq_comp_handler(struct ib_cq *cq, void *context) +{ + struct rds_connection *conn = context; + struct rds_iw_connection *ic = conn->c_transport_data; + struct ib_wc wc; + struct rds_iw_send_work *send; + u32 completed; + u32 oldest; + u32 i; + int ret; + + rdsdebug("cq %p conn %p\n", cq, conn); + rds_iw_stats_inc(s_iw_tx_cq_call); + ret = ib_req_notify_cq(cq, IB_CQ_NEXT_COMP); + if (ret) + rdsdebug("ib_req_notify_cq send failed: %d\n", ret); + + while (ib_poll_cq(cq, 1, &wc) > 0) { + rdsdebug("wc wr_id 0x%llx status %u byte_len %u imm_data %u\n", + (unsigned long long)wc.wr_id, wc.status, wc.byte_len, + be32_to_cpu(wc.ex.imm_data)); + rds_iw_stats_inc(s_iw_tx_cq_event); + + if (wc.status != IB_WC_SUCCESS) { + printk(KERN_ERR "WC Error: status = %d opcode = %d\n", wc.status, wc.opcode); + break; + } + + if (wc.opcode == IB_WC_LOCAL_INV && wc.wr_id == RDS_IW_LOCAL_INV_WR_ID) { + ic->i_fastreg_posted = 0; + continue; + } + + if (wc.opcode == IB_WC_FAST_REG_MR && wc.wr_id == RDS_IW_FAST_REG_WR_ID) { + ic->i_fastreg_posted = 1; + continue; + } + + if (wc.wr_id == RDS_IW_ACK_WR_ID) { + if (ic->i_ack_queued + HZ/2 < jiffies) + rds_iw_stats_inc(s_iw_tx_stalled); + rds_iw_ack_send_complete(ic); + continue; + } + + oldest = rds_iw_ring_oldest(&ic->i_send_ring); + + completed = rds_iw_ring_completed(&ic->i_send_ring, wc.wr_id, oldest); + + for (i = 0; i < completed; i++) { + send = &ic->i_sends[oldest]; + + /* In the error case, wc.opcode sometimes contains garbage */ + switch (send->s_wr.opcode) { + case IB_WR_SEND: + if (send->s_rm) + rds_iw_send_unmap_rm(ic, send, wc.status); + break; + case IB_WR_FAST_REG_MR: + case IB_WR_RDMA_WRITE: + case IB_WR_RDMA_READ: + case IB_WR_RDMA_READ_WITH_INV: + /* Nothing to be done - the SG list will be unmapped + * when the SEND completes. */ + break; + default: + if (printk_ratelimit()) + printk(KERN_NOTICE + "RDS/IW: %s: unexpected opcode 0x%x in WR!\n", + __func__, send->s_wr.opcode); + break; + } + + send->s_wr.opcode = 0xdead; + send->s_wr.num_sge = 1; + if (send->s_queued + HZ/2 < jiffies) + rds_iw_stats_inc(s_iw_tx_stalled); + + /* If a RDMA operation produced an error, signal this right + * away. If we don't, the subsequent SEND that goes with this + * RDMA will be canceled with ERR_WFLUSH, and the application + * never learn that the RDMA failed. */ + if (unlikely(wc.status == IB_WC_REM_ACCESS_ERR && send->s_op)) { + struct rds_message *rm; + + rm = rds_send_get_message(conn, send->s_op); + if (rm) + rds_iw_send_rdma_complete(rm, wc.status); + } + + oldest = (oldest + 1) % ic->i_send_ring.w_nr; + } + + rds_iw_ring_free(&ic->i_send_ring, completed); + + if (test_and_clear_bit(RDS_LL_SEND_FULL, &conn->c_flags) + || test_bit(0, &conn->c_map_queued)) + queue_delayed_work(rds_wq, &conn->c_send_w, 0); + + /* We expect errors as the qp is drained during shutdown */ + if (wc.status != IB_WC_SUCCESS && rds_conn_up(conn)) { + rds_iw_conn_error(conn, + "send completion on %pI4 " + "had status %u, disconnecting and reconnecting\n", + &conn->c_faddr, wc.status); + } + } +} + +/* + * This is the main function for allocating credits when sending + * messages. + * + * Conceptually, we have two counters: + * - send credits: this tells us how many WRs we're allowed + * to submit without overruning the reciever's queue. For + * each SEND WR we post, we decrement this by one. + * + * - posted credits: this tells us how many WRs we recently + * posted to the receive queue. This value is transferred + * to the peer as a "credit update" in a RDS header field. + * Every time we transmit credits to the peer, we subtract + * the amount of transferred credits from this counter. + * + * It is essential that we avoid situations where both sides have + * exhausted their send credits, and are unable to send new credits + * to the peer. We achieve this by requiring that we send at least + * one credit update to the peer before exhausting our credits. + * When new credits arrive, we subtract one credit that is withheld + * until we've posted new buffers and are ready to transmit these + * credits (see rds_iw_send_add_credits below). + * + * The RDS send code is essentially single-threaded; rds_send_xmit + * grabs c_send_lock to ensure exclusive access to the send ring. + * However, the ACK sending code is independent and can race with + * message SENDs. + * + * In the send path, we need to update the counters for send credits + * and the counter of posted buffers atomically - when we use the + * last available credit, we cannot allow another thread to race us + * and grab the posted credits counter. Hence, we have to use a + * spinlock to protect the credit counter, or use atomics. + * + * Spinlocks shared between the send and the receive path are bad, + * because they create unnecessary delays. An early implementation + * using a spinlock showed a 5% degradation in throughput at some + * loads. + * + * This implementation avoids spinlocks completely, putting both + * counters into a single atomic, and updating that atomic using + * atomic_add (in the receive path, when receiving fresh credits), + * and using atomic_cmpxchg when updating the two counters. + */ +int rds_iw_send_grab_credits(struct rds_iw_connection *ic, + u32 wanted, u32 *adv_credits, int need_posted) +{ + unsigned int avail, posted, got = 0, advertise; + long oldval, newval; + + *adv_credits = 0; + if (!ic->i_flowctl) + return wanted; + +try_again: + advertise = 0; + oldval = newval = atomic_read(&ic->i_credits); + posted = IB_GET_POST_CREDITS(oldval); + avail = IB_GET_SEND_CREDITS(oldval); + + rdsdebug("rds_iw_send_grab_credits(%u): credits=%u posted=%u\n", + wanted, avail, posted); + + /* The last credit must be used to send a credit update. */ + if (avail && !posted) + avail--; + + if (avail < wanted) { + struct rds_connection *conn = ic->i_cm_id->context; + + /* Oops, there aren't that many credits left! */ + set_bit(RDS_LL_SEND_FULL, &conn->c_flags); + got = avail; + } else { + /* Sometimes you get what you want, lalala. */ + got = wanted; + } + newval -= IB_SET_SEND_CREDITS(got); + + /* + * If need_posted is non-zero, then the caller wants + * the posted regardless of whether any send credits are + * available. + */ + if (posted && (got || need_posted)) { + advertise = min_t(unsigned int, posted, RDS_MAX_ADV_CREDIT); + newval -= IB_SET_POST_CREDITS(advertise); + } + + /* Finally bill everything */ + if (atomic_cmpxchg(&ic->i_credits, oldval, newval) != oldval) + goto try_again; + + *adv_credits = advertise; + return got; +} + +void rds_iw_send_add_credits(struct rds_connection *conn, unsigned int credits) +{ + struct rds_iw_connection *ic = conn->c_transport_data; + + if (credits == 0) + return; + + rdsdebug("rds_iw_send_add_credits(%u): current=%u%s\n", + credits, + IB_GET_SEND_CREDITS(atomic_read(&ic->i_credits)), + test_bit(RDS_LL_SEND_FULL, &conn->c_flags) ? ", ll_send_full" : ""); + + atomic_add(IB_SET_SEND_CREDITS(credits), &ic->i_credits); + if (test_and_clear_bit(RDS_LL_SEND_FULL, &conn->c_flags)) + queue_delayed_work(rds_wq, &conn->c_send_w, 0); + + WARN_ON(IB_GET_SEND_CREDITS(credits) >= 16384); + + rds_iw_stats_inc(s_iw_rx_credit_updates); +} + +void rds_iw_advertise_credits(struct rds_connection *conn, unsigned int posted) +{ + struct rds_iw_connection *ic = conn->c_transport_data; + + if (posted == 0) + return; + + atomic_add(IB_SET_POST_CREDITS(posted), &ic->i_credits); + + /* Decide whether to send an update to the peer now. + * If we would send a credit update for every single buffer we + * post, we would end up with an ACK storm (ACK arrives, + * consumes buffer, we refill the ring, send ACK to remote + * advertising the newly posted buffer... ad inf) + * + * Performance pretty much depends on how often we send + * credit updates - too frequent updates mean lots of ACKs. + * Too infrequent updates, and the peer will run out of + * credits and has to throttle. + * For the time being, 16 seems to be a good compromise. + */ + if (IB_GET_POST_CREDITS(atomic_read(&ic->i_credits)) >= 16) + set_bit(IB_ACK_REQUESTED, &ic->i_ack_flags); +} + +static inline void +rds_iw_xmit_populate_wr(struct rds_iw_connection *ic, + struct rds_iw_send_work *send, unsigned int pos, + unsigned long buffer, unsigned int length, + int send_flags) +{ + struct ib_sge *sge; + + WARN_ON(pos != send - ic->i_sends); + + send->s_wr.send_flags = send_flags; + send->s_wr.opcode = IB_WR_SEND; + send->s_wr.num_sge = 2; + send->s_wr.next = NULL; + send->s_queued = jiffies; + send->s_op = NULL; + + if (length != 0) { + sge = rds_iw_data_sge(ic, send->s_sge); + sge->addr = buffer; + sge->length = length; + sge->lkey = rds_iw_local_dma_lkey(ic); + + sge = rds_iw_header_sge(ic, send->s_sge); + } else { + /* We're sending a packet with no payload. There is only + * one SGE */ + send->s_wr.num_sge = 1; + sge = &send->s_sge[0]; + } + + sge->addr = ic->i_send_hdrs_dma + (pos * sizeof(struct rds_header)); + sge->length = sizeof(struct rds_header); + sge->lkey = rds_iw_local_dma_lkey(ic); +} + +/* + * This can be called multiple times for a given message. The first time + * we see a message we map its scatterlist into the IB device so that + * we can provide that mapped address to the IB scatter gather entries + * in the IB work requests. We translate the scatterlist into a series + * of work requests that fragment the message. These work requests complete + * in order so we pass ownership of the message to the completion handler + * once we send the final fragment. + * + * The RDS core uses the c_send_lock to only enter this function once + * per connection. This makes sure that the tx ring alloc/unalloc pairs + * don't get out of sync and confuse the ring. + */ +int rds_iw_xmit(struct rds_connection *conn, struct rds_message *rm, + unsigned int hdr_off, unsigned int sg, unsigned int off) +{ + struct rds_iw_connection *ic = conn->c_transport_data; + struct ib_device *dev = ic->i_cm_id->device; + struct rds_iw_send_work *send = NULL; + struct rds_iw_send_work *first; + struct rds_iw_send_work *prev; + struct ib_send_wr *failed_wr; + struct scatterlist *scat; + u32 pos; + u32 i; + u32 work_alloc; + u32 credit_alloc; + u32 posted; + u32 adv_credits = 0; + int send_flags = 0; + int sent; + int ret; + int flow_controlled = 0; + + BUG_ON(off % RDS_FRAG_SIZE); + BUG_ON(hdr_off != 0 && hdr_off != sizeof(struct rds_header)); + + /* Fastreg support */ + if (rds_rdma_cookie_key(rm->m_rdma_cookie) + && !ic->i_fastreg_posted) { + ret = -EAGAIN; + goto out; + } + + /* FIXME we may overallocate here */ + if (be32_to_cpu(rm->m_inc.i_hdr.h_len) == 0) + i = 1; + else + i = ceil(be32_to_cpu(rm->m_inc.i_hdr.h_len), RDS_FRAG_SIZE); + + work_alloc = rds_iw_ring_alloc(&ic->i_send_ring, i, &pos); + if (work_alloc == 0) { + set_bit(RDS_LL_SEND_FULL, &conn->c_flags); + rds_iw_stats_inc(s_iw_tx_ring_full); + ret = -ENOMEM; + goto out; + } + + credit_alloc = work_alloc; + if (ic->i_flowctl) { + credit_alloc = rds_iw_send_grab_credits(ic, work_alloc, &posted, 0); + adv_credits += posted; + if (credit_alloc < work_alloc) { + rds_iw_ring_unalloc(&ic->i_send_ring, work_alloc - credit_alloc); + work_alloc = credit_alloc; + flow_controlled++; + } + if (work_alloc == 0) { + rds_iw_ring_unalloc(&ic->i_send_ring, work_alloc); + rds_iw_stats_inc(s_iw_tx_throttle); + ret = -ENOMEM; + goto out; + } + } + + /* map the message the first time we see it */ + if (ic->i_rm == NULL) { + /* + printk(KERN_NOTICE "rds_iw_xmit prep msg dport=%u flags=0x%x len=%d\n", + be16_to_cpu(rm->m_inc.i_hdr.h_dport), + rm->m_inc.i_hdr.h_flags, + be32_to_cpu(rm->m_inc.i_hdr.h_len)); + */ + if (rm->m_nents) { + rm->m_count = ib_dma_map_sg(dev, + rm->m_sg, rm->m_nents, DMA_TO_DEVICE); + rdsdebug("ic %p mapping rm %p: %d\n", ic, rm, rm->m_count); + if (rm->m_count == 0) { + rds_iw_stats_inc(s_iw_tx_sg_mapping_failure); + rds_iw_ring_unalloc(&ic->i_send_ring, work_alloc); + ret = -ENOMEM; /* XXX ? */ + goto out; + } + } else { + rm->m_count = 0; + } + + ic->i_unsignaled_wrs = rds_iw_sysctl_max_unsig_wrs; + ic->i_unsignaled_bytes = rds_iw_sysctl_max_unsig_bytes; + rds_message_addref(rm); + ic->i_rm = rm; + + /* Finalize the header */ + if (test_bit(RDS_MSG_ACK_REQUIRED, &rm->m_flags)) + rm->m_inc.i_hdr.h_flags |= RDS_FLAG_ACK_REQUIRED; + if (test_bit(RDS_MSG_RETRANSMITTED, &rm->m_flags)) + rm->m_inc.i_hdr.h_flags |= RDS_FLAG_RETRANSMITTED; + + /* If it has a RDMA op, tell the peer we did it. This is + * used by the peer to release use-once RDMA MRs. */ + if (rm->m_rdma_op) { + struct rds_ext_header_rdma ext_hdr; + + ext_hdr.h_rdma_rkey = cpu_to_be32(rm->m_rdma_op->r_key); + rds_message_add_extension(&rm->m_inc.i_hdr, + RDS_EXTHDR_RDMA, &ext_hdr, sizeof(ext_hdr)); + } + if (rm->m_rdma_cookie) { + rds_message_add_rdma_dest_extension(&rm->m_inc.i_hdr, + rds_rdma_cookie_key(rm->m_rdma_cookie), + rds_rdma_cookie_offset(rm->m_rdma_cookie)); + } + + /* Note - rds_iw_piggyb_ack clears the ACK_REQUIRED bit, so + * we should not do this unless we have a chance of at least + * sticking the header into the send ring. Which is why we + * should call rds_iw_ring_alloc first. */ + rm->m_inc.i_hdr.h_ack = cpu_to_be64(rds_iw_piggyb_ack(ic)); + rds_message_make_checksum(&rm->m_inc.i_hdr); + + /* + * Update adv_credits since we reset the ACK_REQUIRED bit. + */ + rds_iw_send_grab_credits(ic, 0, &posted, 1); + adv_credits += posted; + BUG_ON(adv_credits > 255); + } else if (ic->i_rm != rm) + BUG(); + + send = &ic->i_sends[pos]; + first = send; + prev = NULL; + scat = &rm->m_sg[sg]; + sent = 0; + i = 0; + + /* Sometimes you want to put a fence between an RDMA + * READ and the following SEND. + * We could either do this all the time + * or when requested by the user. Right now, we let + * the application choose. + */ + if (rm->m_rdma_op && rm->m_rdma_op->r_fence) + send_flags = IB_SEND_FENCE; + + /* + * We could be copying the header into the unused tail of the page. + * That would need to be changed in the future when those pages might + * be mapped userspace pages or page cache pages. So instead we always + * use a second sge and our long-lived ring of mapped headers. We send + * the header after the data so that the data payload can be aligned on + * the receiver. + */ + + /* handle a 0-len message */ + if (be32_to_cpu(rm->m_inc.i_hdr.h_len) == 0) { + rds_iw_xmit_populate_wr(ic, send, pos, 0, 0, send_flags); + goto add_header; + } + + /* if there's data reference it with a chain of work reqs */ + for (; i < work_alloc && scat != &rm->m_sg[rm->m_count]; i++) { + unsigned int len; + + send = &ic->i_sends[pos]; + + len = min(RDS_FRAG_SIZE, ib_sg_dma_len(dev, scat) - off); + rds_iw_xmit_populate_wr(ic, send, pos, + ib_sg_dma_address(dev, scat) + off, len, + send_flags); + + /* + * We want to delay signaling completions just enough to get + * the batching benefits but not so much that we create dead time + * on the wire. + */ + if (ic->i_unsignaled_wrs-- == 0) { + ic->i_unsignaled_wrs = rds_iw_sysctl_max_unsig_wrs; + send->s_wr.send_flags |= IB_SEND_SIGNALED | IB_SEND_SOLICITED; + } + + ic->i_unsignaled_bytes -= len; + if (ic->i_unsignaled_bytes <= 0) { + ic->i_unsignaled_bytes = rds_iw_sysctl_max_unsig_bytes; + send->s_wr.send_flags |= IB_SEND_SIGNALED | IB_SEND_SOLICITED; + } + + /* + * Always signal the last one if we're stopping due to flow control. + */ + if (flow_controlled && i == (work_alloc-1)) + send->s_wr.send_flags |= IB_SEND_SIGNALED | IB_SEND_SOLICITED; + + rdsdebug("send %p wr %p num_sge %u next %p\n", send, + &send->s_wr, send->s_wr.num_sge, send->s_wr.next); + + sent += len; + off += len; + if (off == ib_sg_dma_len(dev, scat)) { + scat++; + off = 0; + } + +add_header: + /* Tack on the header after the data. The header SGE should already + * have been set up to point to the right header buffer. */ + memcpy(&ic->i_send_hdrs[pos], &rm->m_inc.i_hdr, sizeof(struct rds_header)); + + if (0) { + struct rds_header *hdr = &ic->i_send_hdrs[pos]; + + printk(KERN_NOTICE "send WR dport=%u flags=0x%x len=%d\n", + be16_to_cpu(hdr->h_dport), + hdr->h_flags, + be32_to_cpu(hdr->h_len)); + } + if (adv_credits) { + struct rds_header *hdr = &ic->i_send_hdrs[pos]; + + /* add credit and redo the header checksum */ + hdr->h_credit = adv_credits; + rds_message_make_checksum(hdr); + adv_credits = 0; + rds_iw_stats_inc(s_iw_tx_credit_updates); + } + + if (prev) + prev->s_wr.next = &send->s_wr; + prev = send; + + pos = (pos + 1) % ic->i_send_ring.w_nr; + } + + /* Account the RDS header in the number of bytes we sent, but just once. + * The caller has no concept of fragmentation. */ + if (hdr_off == 0) + sent += sizeof(struct rds_header); + + /* if we finished the message then send completion owns it */ + if (scat == &rm->m_sg[rm->m_count]) { + prev->s_rm = ic->i_rm; + prev->s_wr.send_flags |= IB_SEND_SIGNALED | IB_SEND_SOLICITED; + ic->i_rm = NULL; + } + + if (i < work_alloc) { + rds_iw_ring_unalloc(&ic->i_send_ring, work_alloc - i); + work_alloc = i; + } + if (ic->i_flowctl && i < credit_alloc) + rds_iw_send_add_credits(conn, credit_alloc - i); + + /* XXX need to worry about failed_wr and partial sends. */ + failed_wr = &first->s_wr; + ret = ib_post_send(ic->i_cm_id->qp, &first->s_wr, &failed_wr); + rdsdebug("ic %p first %p (wr %p) ret %d wr %p\n", ic, + first, &first->s_wr, ret, failed_wr); + BUG_ON(failed_wr != &first->s_wr); + if (ret) { + printk(KERN_WARNING "RDS/IW: ib_post_send to %pI4 " + "returned %d\n", &conn->c_faddr, ret); + rds_iw_ring_unalloc(&ic->i_send_ring, work_alloc); + if (prev->s_rm) { + ic->i_rm = prev->s_rm; + prev->s_rm = NULL; + } + goto out; + } + + ret = sent; +out: + BUG_ON(adv_credits); + return ret; +} + +static void rds_iw_build_send_fastreg(struct rds_iw_device *rds_iwdev, struct rds_iw_connection *ic, struct rds_iw_send_work *send, int nent, int len, u64 sg_addr) +{ + BUG_ON(nent > send->s_page_list->max_page_list_len); + /* + * Perform a WR for the fast_reg_mr. Each individual page + * in the sg list is added to the fast reg page list and placed + * inside the fast_reg_mr WR. + */ + send->s_wr.opcode = IB_WR_FAST_REG_MR; + send->s_wr.wr.fast_reg.length = len; + send->s_wr.wr.fast_reg.rkey = send->s_mr->rkey; + send->s_wr.wr.fast_reg.page_list = send->s_page_list; + send->s_wr.wr.fast_reg.page_list_len = nent; + send->s_wr.wr.fast_reg.page_shift = rds_iwdev->page_shift; + send->s_wr.wr.fast_reg.access_flags = IB_ACCESS_REMOTE_WRITE; + send->s_wr.wr.fast_reg.iova_start = sg_addr; + + ib_update_fast_reg_key(send->s_mr, send->s_remap_count++); +} + +int rds_iw_xmit_rdma(struct rds_connection *conn, struct rds_rdma_op *op) +{ + struct rds_iw_connection *ic = conn->c_transport_data; + struct rds_iw_send_work *send = NULL; + struct rds_iw_send_work *first; + struct rds_iw_send_work *prev; + struct ib_send_wr *failed_wr; + struct rds_iw_device *rds_iwdev; + struct scatterlist *scat; + unsigned long len; + u64 remote_addr = op->r_remote_addr; + u32 pos, fr_pos; + u32 work_alloc; + u32 i; + u32 j; + int sent; + int ret; + int num_sge; + + rds_iwdev = ib_get_client_data(ic->i_cm_id->device, &rds_iw_client); + + /* map the message the first time we see it */ + if (!op->r_mapped) { + op->r_count = ib_dma_map_sg(ic->i_cm_id->device, + op->r_sg, op->r_nents, (op->r_write) ? + DMA_TO_DEVICE : DMA_FROM_DEVICE); + rdsdebug("ic %p mapping op %p: %d\n", ic, op, op->r_count); + if (op->r_count == 0) { + rds_iw_stats_inc(s_iw_tx_sg_mapping_failure); + ret = -ENOMEM; /* XXX ? */ + goto out; + } + + op->r_mapped = 1; + } + + if (!op->r_write) { + /* Alloc space on the send queue for the fastreg */ + work_alloc = rds_iw_ring_alloc(&ic->i_send_ring, 1, &fr_pos); + if (work_alloc != 1) { + rds_iw_ring_unalloc(&ic->i_send_ring, work_alloc); + rds_iw_stats_inc(s_iw_tx_ring_full); + ret = -ENOMEM; + goto out; + } + } + + /* + * Instead of knowing how to return a partial rdma read/write we insist that there + * be enough work requests to send the entire message. + */ + i = ceil(op->r_count, rds_iwdev->max_sge); + + work_alloc = rds_iw_ring_alloc(&ic->i_send_ring, i, &pos); + if (work_alloc != i) { + rds_iw_ring_unalloc(&ic->i_send_ring, work_alloc); + rds_iw_stats_inc(s_iw_tx_ring_full); + ret = -ENOMEM; + goto out; + } + + send = &ic->i_sends[pos]; + if (!op->r_write) { + first = prev = &ic->i_sends[fr_pos]; + } else { + first = send; + prev = NULL; + } + scat = &op->r_sg[0]; + sent = 0; + num_sge = op->r_count; + + for (i = 0; i < work_alloc && scat != &op->r_sg[op->r_count]; i++) { + send->s_wr.send_flags = 0; + send->s_queued = jiffies; + + /* + * We want to delay signaling completions just enough to get + * the batching benefits but not so much that we create dead time on the wire. + */ + if (ic->i_unsignaled_wrs-- == 0) { + ic->i_unsignaled_wrs = rds_iw_sysctl_max_unsig_wrs; + send->s_wr.send_flags = IB_SEND_SIGNALED; + } + + /* To avoid the need to have the plumbing to invalidate the fastreg_mr used + * for local access after RDS is finished with it, using + * IB_WR_RDMA_READ_WITH_INV will invalidate it after the read has completed. + */ + if (op->r_write) + send->s_wr.opcode = IB_WR_RDMA_WRITE; + else + send->s_wr.opcode = IB_WR_RDMA_READ_WITH_INV; + + send->s_wr.wr.rdma.remote_addr = remote_addr; + send->s_wr.wr.rdma.rkey = op->r_key; + send->s_op = op; + + if (num_sge > rds_iwdev->max_sge) { + send->s_wr.num_sge = rds_iwdev->max_sge; + num_sge -= rds_iwdev->max_sge; + } else + send->s_wr.num_sge = num_sge; + + send->s_wr.next = NULL; + + if (prev) + prev->s_wr.next = &send->s_wr; + + for (j = 0; j < send->s_wr.num_sge && scat != &op->r_sg[op->r_count]; j++) { + len = ib_sg_dma_len(ic->i_cm_id->device, scat); + + if (send->s_wr.opcode == IB_WR_RDMA_READ_WITH_INV) + send->s_page_list->page_list[j] = ib_sg_dma_address(ic->i_cm_id->device, scat); + else { + send->s_sge[j].addr = ib_sg_dma_address(ic->i_cm_id->device, scat); + send->s_sge[j].length = len; + send->s_sge[j].lkey = rds_iw_local_dma_lkey(ic); + } + + sent += len; + rdsdebug("ic %p sent %d remote_addr %llu\n", ic, sent, remote_addr); + remote_addr += len; + + scat++; + } + + if (send->s_wr.opcode == IB_WR_RDMA_READ_WITH_INV) { + send->s_wr.num_sge = 1; + send->s_sge[0].addr = conn->c_xmit_rm->m_rs->rs_user_addr; + send->s_sge[0].length = conn->c_xmit_rm->m_rs->rs_user_bytes; + send->s_sge[0].lkey = ic->i_sends[fr_pos].s_mr->lkey; + } + + rdsdebug("send %p wr %p num_sge %u next %p\n", send, + &send->s_wr, send->s_wr.num_sge, send->s_wr.next); + + prev = send; + if (++send == &ic->i_sends[ic->i_send_ring.w_nr]) + send = ic->i_sends; + } + + /* if we finished the message then send completion owns it */ + if (scat == &op->r_sg[op->r_count]) + first->s_wr.send_flags = IB_SEND_SIGNALED; + + if (i < work_alloc) { + rds_iw_ring_unalloc(&ic->i_send_ring, work_alloc - i); + work_alloc = i; + } + + /* On iWARP, local memory access by a remote system (ie, RDMA Read) is not + * recommended. Putting the lkey on the wire is a security hole, as it can + * allow for memory access to all of memory on the remote system. Some + * adapters do not allow using the lkey for this at all. To bypass this use a + * fastreg_mr (or possibly a dma_mr) + */ + if (!op->r_write) { + rds_iw_build_send_fastreg(rds_iwdev, ic, &ic->i_sends[fr_pos], + op->r_count, sent, conn->c_xmit_rm->m_rs->rs_user_addr); + work_alloc++; + } + + failed_wr = &first->s_wr; + ret = ib_post_send(ic->i_cm_id->qp, &first->s_wr, &failed_wr); + rdsdebug("ic %p first %p (wr %p) ret %d wr %p\n", ic, + first, &first->s_wr, ret, failed_wr); + BUG_ON(failed_wr != &first->s_wr); + if (ret) { + printk(KERN_WARNING "RDS/IW: rdma ib_post_send to %pI4 " + "returned %d\n", &conn->c_faddr, ret); + rds_iw_ring_unalloc(&ic->i_send_ring, work_alloc); + goto out; + } + +out: + return ret; +} + +void rds_iw_xmit_complete(struct rds_connection *conn) +{ + struct rds_iw_connection *ic = conn->c_transport_data; + + /* We may have a pending ACK or window update we were unable + * to send previously (due to flow control). Try again. */ + rds_iw_attempt_ack(ic); +} diff --git a/net/rds/iw_stats.c b/net/rds/iw_stats.c new file mode 100644 index 0000000..ccc7e8f --- /dev/null +++ b/net/rds/iw_stats.c @@ -0,0 +1,95 @@ +/* + * Copyright (c) 2006 Oracle. All rights reserved. + * + * This software is available to you under a choice of one of two + * licenses. You may choose to be licensed under the terms of the GNU + * General Public License (GPL) Version 2, available from the file + * COPYING in the main directory of this source tree, or the + * OpenIB.org BSD license below: + * + * 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 + * copyright notice, this list of conditions and the following + * disclaimer in the documentation and/or other materials + * provided with the distribution. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + * + */ +#include <linux/percpu.h> +#include <linux/seq_file.h> +#include <linux/proc_fs.h> + +#include "rds.h" +#include "iw.h" + +DEFINE_PER_CPU(struct rds_iw_statistics, rds_iw_stats) ____cacheline_aligned; + +static char *rds_iw_stat_names[] = { + "iw_connect_raced", + "iw_listen_closed_stale", + "iw_tx_cq_call", + "iw_tx_cq_event", + "iw_tx_ring_full", + "iw_tx_throttle", + "iw_tx_sg_mapping_failure", + "iw_tx_stalled", + "iw_tx_credit_updates", + "iw_rx_cq_call", + "iw_rx_cq_event", + "iw_rx_ring_empty", + "iw_rx_refill_from_cq", + "iw_rx_refill_from_thread", + "iw_rx_alloc_limit", + "iw_rx_credit_updates", + "iw_ack_sent", + "iw_ack_send_failure", + "iw_ack_send_delayed", + "iw_ack_send_piggybacked", + "iw_ack_received", + "iw_rdma_mr_alloc", + "iw_rdma_mr_free", + "iw_rdma_mr_used", + "iw_rdma_mr_pool_flush", + "iw_rdma_mr_pool_wait", + "iw_rdma_mr_pool_depleted", +}; + +unsigned int rds_iw_stats_info_copy(struct rds_info_iterator *iter, + unsigned int avail) +{ + struct rds_iw_statistics stats = {0, }; + uint64_t *src; + uint64_t *sum; + size_t i; + int cpu; + + if (avail < ARRAY_SIZE(rds_iw_stat_names)) + goto out; + + for_each_online_cpu(cpu) { + src = (uint64_t *)&(per_cpu(rds_iw_stats, cpu)); + sum = (uint64_t *)&stats; + for (i = 0; i < sizeof(stats) / sizeof(uint64_t); i++) + *(sum++) += *(src++); + } + + rds_stats_info_copy(iter, (uint64_t *)&stats, rds_iw_stat_names, + ARRAY_SIZE(rds_iw_stat_names)); +out: + return ARRAY_SIZE(rds_iw_stat_names); +} diff --git a/net/rds/iw_sysctl.c b/net/rds/iw_sysctl.c new file mode 100644 index 0000000..9590678 --- /dev/null +++ b/net/rds/iw_sysctl.c @@ -0,0 +1,137 @@ +/* + * Copyright (c) 2006 Oracle. All rights reserved. + * + * This software is available to you under a choice of one of two + * licenses. You may choose to be licensed under the terms of the GNU + * General Public License (GPL) Version 2, available from the file + * COPYING in the main directory of this source tree, or the + * OpenIB.org BSD license below: + * + * 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 + * copyright notice, this list of conditions and the following + * disclaimer in the documentation and/or other materials + * provided with the distribution. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + * + */ +#include <linux/kernel.h> +#include <linux/sysctl.h> +#include <linux/proc_fs.h> + +#include "iw.h" + +static struct ctl_table_header *rds_iw_sysctl_hdr; + +unsigned long rds_iw_sysctl_max_send_wr = RDS_IW_DEFAULT_SEND_WR; +unsigned long rds_iw_sysctl_max_recv_wr = RDS_IW_DEFAULT_RECV_WR; +unsigned long rds_iw_sysctl_max_recv_allocation = (128 * 1024 * 1024) / RDS_FRAG_SIZE; +static unsigned long rds_iw_sysctl_max_wr_min = 1; +/* hardware will fail CQ creation long before this */ +static unsigned long rds_iw_sysctl_max_wr_max = (u32)~0; + +unsigned long rds_iw_sysctl_max_unsig_wrs = 16; +static unsigned long rds_iw_sysctl_max_unsig_wr_min = 1; +static unsigned long rds_iw_sysctl_max_unsig_wr_max = 64; + +unsigned long rds_iw_sysctl_max_unsig_bytes = (16 << 20); +static unsigned long rds_iw_sysctl_max_unsig_bytes_min = 1; +static unsigned long rds_iw_sysctl_max_unsig_bytes_max = ~0UL; + +unsigned int rds_iw_sysctl_flow_control = 1; + +ctl_table rds_iw_sysctl_table[] = { + { + .ctl_name = CTL_UNNUMBERED, + .procname = "max_send_wr", + .data = &rds_iw_sysctl_max_send_wr, + .maxlen = sizeof(unsigned long), + .mode = 0644, + .proc_handler = &proc_doulongvec_minmax, + .extra1 = &rds_iw_sysctl_max_wr_min, + .extra2 = &rds_iw_sysctl_max_wr_max, + }, + { + .ctl_name = CTL_UNNUMBERED, + .procname = "max_recv_wr", + .data = &rds_iw_sysctl_max_recv_wr, + .maxlen = sizeof(unsigned long), + .mode = 0644, + .proc_handler = &proc_doulongvec_minmax, + .extra1 = &rds_iw_sysctl_max_wr_min, + .extra2 = &rds_iw_sysctl_max_wr_max, + }, + { + .ctl_name = CTL_UNNUMBERED, + .procname = "max_unsignaled_wr", + .data = &rds_iw_sysctl_max_unsig_wrs, + .maxlen = sizeof(unsigned long), + .mode = 0644, + .proc_handler = &proc_doulongvec_minmax, + .extra1 = &rds_iw_sysctl_max_unsig_wr_min, + .extra2 = &rds_iw_sysctl_max_unsig_wr_max, + }, + { + .ctl_name = CTL_UNNUMBERED, + .procname = "max_unsignaled_bytes", + .data = &rds_iw_sysctl_max_unsig_bytes, + .maxlen = sizeof(unsigned long), + .mode = 0644, + .proc_handler = &proc_doulongvec_minmax, + .extra1 = &rds_iw_sysctl_max_unsig_bytes_min, + .extra2 = &rds_iw_sysctl_max_unsig_bytes_max, + }, + { + .ctl_name = CTL_UNNUMBERED, + .procname = "max_recv_allocation", + .data = &rds_iw_sysctl_max_recv_allocation, + .maxlen = sizeof(unsigned long), + .mode = 0644, + .proc_handler = &proc_doulongvec_minmax, + }, + { + .ctl_name = CTL_UNNUMBERED, + .procname = "flow_control", + .data = &rds_iw_sysctl_flow_control, + .maxlen = sizeof(rds_iw_sysctl_flow_control), + .mode = 0644, + .proc_handler = &proc_dointvec, + }, + { .ctl_name = 0} +}; + +static struct ctl_path rds_iw_sysctl_path[] = { + { .procname = "net", .ctl_name = CTL_NET, }, + { .procname = "rds", .ctl_name = CTL_UNNUMBERED, }, + { .procname = "iw", .ctl_name = CTL_UNNUMBERED, }, + { } +}; + +void rds_iw_sysctl_exit(void) +{ + if (rds_iw_sysctl_hdr) + unregister_sysctl_table(rds_iw_sysctl_hdr); +} + +int __init rds_iw_sysctl_init(void) +{ + rds_iw_sysctl_hdr = register_sysctl_paths(rds_iw_sysctl_path, rds_iw_sysctl_table); + if (rds_iw_sysctl_hdr == NULL) + return -ENOMEM; + return 0; +} |