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2046 lines
47 KiB
2046 lines
47 KiB
// SPDX-License-Identifier: GPL-2.0-only |
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/****************************************************************************** |
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******************************************************************************* |
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** |
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** Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. |
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** Copyright (C) 2004-2009 Red Hat, Inc. All rights reserved. |
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** |
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** |
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******************************************************************************* |
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******************************************************************************/ |
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|
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/* |
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* lowcomms.c |
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* |
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* This is the "low-level" comms layer. |
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* |
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* It is responsible for sending/receiving messages |
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* from other nodes in the cluster. |
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* |
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* Cluster nodes are referred to by their nodeids. nodeids are |
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* simply 32 bit numbers to the locking module - if they need to |
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* be expanded for the cluster infrastructure then that is its |
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* responsibility. It is this layer's |
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* responsibility to resolve these into IP address or |
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* whatever it needs for inter-node communication. |
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* |
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* The comms level is two kernel threads that deal mainly with |
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* the receiving of messages from other nodes and passing them |
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* up to the mid-level comms layer (which understands the |
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* message format) for execution by the locking core, and |
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* a send thread which does all the setting up of connections |
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* to remote nodes and the sending of data. Threads are not allowed |
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* to send their own data because it may cause them to wait in times |
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* of high load. Also, this way, the sending thread can collect together |
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* messages bound for one node and send them in one block. |
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* |
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* lowcomms will choose to use either TCP or SCTP as its transport layer |
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* depending on the configuration variable 'protocol'. This should be set |
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* to 0 (default) for TCP or 1 for SCTP. It should be configured using a |
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* cluster-wide mechanism as it must be the same on all nodes of the cluster |
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* for the DLM to function. |
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* |
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*/ |
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|
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#include <asm/ioctls.h> |
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#include <net/sock.h> |
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#include <net/tcp.h> |
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#include <linux/pagemap.h> |
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#include <linux/file.h> |
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#include <linux/mutex.h> |
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#include <linux/sctp.h> |
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#include <linux/slab.h> |
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#include <net/sctp/sctp.h> |
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#include <net/ipv6.h> |
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|
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#include <trace/events/dlm.h> |
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|
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#include "dlm_internal.h" |
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#include "lowcomms.h" |
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#include "midcomms.h" |
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#include "memory.h" |
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#include "config.h" |
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|
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#define NEEDED_RMEM (4*1024*1024) |
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|
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/* Number of messages to send before rescheduling */ |
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#define MAX_SEND_MSG_COUNT 25 |
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#define DLM_SHUTDOWN_WAIT_TIMEOUT msecs_to_jiffies(10000) |
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|
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struct connection { |
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struct socket *sock; /* NULL if not connected */ |
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uint32_t nodeid; /* So we know who we are in the list */ |
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struct mutex sock_mutex; |
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unsigned long flags; |
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#define CF_READ_PENDING 1 |
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#define CF_WRITE_PENDING 2 |
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#define CF_INIT_PENDING 4 |
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#define CF_IS_OTHERCON 5 |
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#define CF_CLOSE 6 |
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#define CF_APP_LIMITED 7 |
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#define CF_CLOSING 8 |
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#define CF_SHUTDOWN 9 |
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#define CF_CONNECTED 10 |
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#define CF_RECONNECT 11 |
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#define CF_DELAY_CONNECT 12 |
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#define CF_EOF 13 |
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struct list_head writequeue; /* List of outgoing writequeue_entries */ |
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spinlock_t writequeue_lock; |
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atomic_t writequeue_cnt; |
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int retries; |
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#define MAX_CONNECT_RETRIES 3 |
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struct hlist_node list; |
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struct connection *othercon; |
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struct connection *sendcon; |
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struct work_struct rwork; /* Receive workqueue */ |
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struct work_struct swork; /* Send workqueue */ |
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wait_queue_head_t shutdown_wait; /* wait for graceful shutdown */ |
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unsigned char *rx_buf; |
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int rx_buflen; |
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int rx_leftover; |
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struct rcu_head rcu; |
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}; |
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#define sock2con(x) ((struct connection *)(x)->sk_user_data) |
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|
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struct listen_connection { |
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struct socket *sock; |
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struct work_struct rwork; |
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}; |
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|
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#define DLM_WQ_REMAIN_BYTES(e) (PAGE_SIZE - e->end) |
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#define DLM_WQ_LENGTH_BYTES(e) (e->end - e->offset) |
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|
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/* An entry waiting to be sent */ |
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struct writequeue_entry { |
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struct list_head list; |
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struct page *page; |
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int offset; |
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int len; |
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int end; |
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int users; |
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bool dirty; |
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struct connection *con; |
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struct list_head msgs; |
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struct kref ref; |
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}; |
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|
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struct dlm_msg { |
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struct writequeue_entry *entry; |
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struct dlm_msg *orig_msg; |
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bool retransmit; |
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void *ppc; |
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int len; |
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int idx; /* new()/commit() idx exchange */ |
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|
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struct list_head list; |
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struct kref ref; |
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}; |
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|
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struct dlm_node_addr { |
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struct list_head list; |
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int nodeid; |
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int mark; |
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int addr_count; |
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int curr_addr_index; |
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struct sockaddr_storage *addr[DLM_MAX_ADDR_COUNT]; |
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}; |
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|
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struct dlm_proto_ops { |
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bool try_new_addr; |
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const char *name; |
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int proto; |
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|
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int (*connect)(struct connection *con, struct socket *sock, |
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struct sockaddr *addr, int addr_len); |
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void (*sockopts)(struct socket *sock); |
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int (*bind)(struct socket *sock); |
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int (*listen_validate)(void); |
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void (*listen_sockopts)(struct socket *sock); |
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int (*listen_bind)(struct socket *sock); |
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/* What to do to shutdown */ |
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void (*shutdown_action)(struct connection *con); |
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/* What to do to eof check */ |
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bool (*eof_condition)(struct connection *con); |
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}; |
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|
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static struct listen_sock_callbacks { |
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void (*sk_error_report)(struct sock *); |
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void (*sk_data_ready)(struct sock *); |
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void (*sk_state_change)(struct sock *); |
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void (*sk_write_space)(struct sock *); |
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} listen_sock; |
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|
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static LIST_HEAD(dlm_node_addrs); |
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static DEFINE_SPINLOCK(dlm_node_addrs_spin); |
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|
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static struct listen_connection listen_con; |
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static struct sockaddr_storage *dlm_local_addr[DLM_MAX_ADDR_COUNT]; |
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static int dlm_local_count; |
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int dlm_allow_conn; |
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|
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/* Work queues */ |
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static struct workqueue_struct *recv_workqueue; |
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static struct workqueue_struct *send_workqueue; |
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|
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static struct hlist_head connection_hash[CONN_HASH_SIZE]; |
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static DEFINE_SPINLOCK(connections_lock); |
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DEFINE_STATIC_SRCU(connections_srcu); |
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|
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static const struct dlm_proto_ops *dlm_proto_ops; |
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static void process_recv_sockets(struct work_struct *work); |
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static void process_send_sockets(struct work_struct *work); |
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|
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static void writequeue_entry_ctor(void *data) |
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{ |
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struct writequeue_entry *entry = data; |
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|
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INIT_LIST_HEAD(&entry->msgs); |
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} |
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struct kmem_cache *dlm_lowcomms_writequeue_cache_create(void) |
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{ |
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return kmem_cache_create("dlm_writequeue", sizeof(struct writequeue_entry), |
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0, 0, writequeue_entry_ctor); |
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} |
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|
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struct kmem_cache *dlm_lowcomms_msg_cache_create(void) |
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{ |
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return kmem_cache_create("dlm_msg", sizeof(struct dlm_msg), 0, 0, NULL); |
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} |
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|
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/* need to held writequeue_lock */ |
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static struct writequeue_entry *con_next_wq(struct connection *con) |
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{ |
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struct writequeue_entry *e; |
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|
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if (list_empty(&con->writequeue)) |
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return NULL; |
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|
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e = list_first_entry(&con->writequeue, struct writequeue_entry, |
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list); |
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/* if len is zero nothing is to send, if there are users filling |
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* buffers we wait until the users are done so we can send more. |
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*/ |
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if (e->users || e->len == 0) |
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return NULL; |
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|
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return e; |
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} |
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static struct connection *__find_con(int nodeid, int r) |
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{ |
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struct connection *con; |
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|
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hlist_for_each_entry_rcu(con, &connection_hash[r], list) { |
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if (con->nodeid == nodeid) |
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return con; |
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} |
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|
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return NULL; |
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} |
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|
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static bool tcp_eof_condition(struct connection *con) |
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{ |
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return atomic_read(&con->writequeue_cnt); |
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} |
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|
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static int dlm_con_init(struct connection *con, int nodeid) |
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{ |
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con->rx_buflen = dlm_config.ci_buffer_size; |
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con->rx_buf = kmalloc(con->rx_buflen, GFP_NOFS); |
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if (!con->rx_buf) |
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return -ENOMEM; |
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con->nodeid = nodeid; |
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mutex_init(&con->sock_mutex); |
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INIT_LIST_HEAD(&con->writequeue); |
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spin_lock_init(&con->writequeue_lock); |
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atomic_set(&con->writequeue_cnt, 0); |
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INIT_WORK(&con->swork, process_send_sockets); |
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INIT_WORK(&con->rwork, process_recv_sockets); |
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init_waitqueue_head(&con->shutdown_wait); |
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|
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return 0; |
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} |
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/* |
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* If 'allocation' is zero then we don't attempt to create a new |
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* connection structure for this node. |
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*/ |
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static struct connection *nodeid2con(int nodeid, gfp_t alloc) |
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{ |
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struct connection *con, *tmp; |
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int r, ret; |
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r = nodeid_hash(nodeid); |
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con = __find_con(nodeid, r); |
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if (con || !alloc) |
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return con; |
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con = kzalloc(sizeof(*con), alloc); |
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if (!con) |
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return NULL; |
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ret = dlm_con_init(con, nodeid); |
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if (ret) { |
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kfree(con); |
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return NULL; |
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} |
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|
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spin_lock(&connections_lock); |
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/* Because multiple workqueues/threads calls this function it can |
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* race on multiple cpu's. Instead of locking hot path __find_con() |
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* we just check in rare cases of recently added nodes again |
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* under protection of connections_lock. If this is the case we |
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* abort our connection creation and return the existing connection. |
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*/ |
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tmp = __find_con(nodeid, r); |
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if (tmp) { |
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spin_unlock(&connections_lock); |
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kfree(con->rx_buf); |
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kfree(con); |
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return tmp; |
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} |
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hlist_add_head_rcu(&con->list, &connection_hash[r]); |
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spin_unlock(&connections_lock); |
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return con; |
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} |
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/* Loop round all connections */ |
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static void foreach_conn(void (*conn_func)(struct connection *c)) |
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{ |
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int i; |
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struct connection *con; |
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for (i = 0; i < CONN_HASH_SIZE; i++) { |
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hlist_for_each_entry_rcu(con, &connection_hash[i], list) |
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conn_func(con); |
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} |
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} |
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static struct dlm_node_addr *find_node_addr(int nodeid) |
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{ |
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struct dlm_node_addr *na; |
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list_for_each_entry(na, &dlm_node_addrs, list) { |
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if (na->nodeid == nodeid) |
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return na; |
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} |
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return NULL; |
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} |
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|
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static int addr_compare(const struct sockaddr_storage *x, |
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const struct sockaddr_storage *y) |
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{ |
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switch (x->ss_family) { |
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case AF_INET: { |
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struct sockaddr_in *sinx = (struct sockaddr_in *)x; |
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struct sockaddr_in *siny = (struct sockaddr_in *)y; |
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if (sinx->sin_addr.s_addr != siny->sin_addr.s_addr) |
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return 0; |
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if (sinx->sin_port != siny->sin_port) |
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return 0; |
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break; |
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} |
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case AF_INET6: { |
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struct sockaddr_in6 *sinx = (struct sockaddr_in6 *)x; |
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struct sockaddr_in6 *siny = (struct sockaddr_in6 *)y; |
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if (!ipv6_addr_equal(&sinx->sin6_addr, &siny->sin6_addr)) |
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return 0; |
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if (sinx->sin6_port != siny->sin6_port) |
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return 0; |
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break; |
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} |
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default: |
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return 0; |
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} |
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return 1; |
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} |
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|
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static int nodeid_to_addr(int nodeid, struct sockaddr_storage *sas_out, |
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struct sockaddr *sa_out, bool try_new_addr, |
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unsigned int *mark) |
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{ |
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struct sockaddr_storage sas; |
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struct dlm_node_addr *na; |
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|
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if (!dlm_local_count) |
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return -1; |
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spin_lock(&dlm_node_addrs_spin); |
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na = find_node_addr(nodeid); |
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if (na && na->addr_count) { |
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memcpy(&sas, na->addr[na->curr_addr_index], |
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sizeof(struct sockaddr_storage)); |
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|
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if (try_new_addr) { |
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na->curr_addr_index++; |
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if (na->curr_addr_index == na->addr_count) |
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na->curr_addr_index = 0; |
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} |
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} |
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spin_unlock(&dlm_node_addrs_spin); |
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|
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if (!na) |
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return -EEXIST; |
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|
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if (!na->addr_count) |
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return -ENOENT; |
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*mark = na->mark; |
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if (sas_out) |
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memcpy(sas_out, &sas, sizeof(struct sockaddr_storage)); |
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|
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if (!sa_out) |
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return 0; |
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if (dlm_local_addr[0]->ss_family == AF_INET) { |
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struct sockaddr_in *in4 = (struct sockaddr_in *) &sas; |
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struct sockaddr_in *ret4 = (struct sockaddr_in *) sa_out; |
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ret4->sin_addr.s_addr = in4->sin_addr.s_addr; |
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} else { |
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struct sockaddr_in6 *in6 = (struct sockaddr_in6 *) &sas; |
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struct sockaddr_in6 *ret6 = (struct sockaddr_in6 *) sa_out; |
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ret6->sin6_addr = in6->sin6_addr; |
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} |
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|
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return 0; |
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} |
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static int addr_to_nodeid(struct sockaddr_storage *addr, int *nodeid, |
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unsigned int *mark) |
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{ |
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struct dlm_node_addr *na; |
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int rv = -EEXIST; |
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int addr_i; |
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|
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spin_lock(&dlm_node_addrs_spin); |
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list_for_each_entry(na, &dlm_node_addrs, list) { |
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if (!na->addr_count) |
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continue; |
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|
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for (addr_i = 0; addr_i < na->addr_count; addr_i++) { |
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if (addr_compare(na->addr[addr_i], addr)) { |
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*nodeid = na->nodeid; |
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*mark = na->mark; |
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rv = 0; |
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goto unlock; |
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} |
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} |
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} |
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unlock: |
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spin_unlock(&dlm_node_addrs_spin); |
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return rv; |
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} |
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|
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/* caller need to held dlm_node_addrs_spin lock */ |
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static bool dlm_lowcomms_na_has_addr(const struct dlm_node_addr *na, |
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const struct sockaddr_storage *addr) |
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{ |
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int i; |
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|
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for (i = 0; i < na->addr_count; i++) { |
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if (addr_compare(na->addr[i], addr)) |
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return true; |
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} |
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|
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return false; |
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} |
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|
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int dlm_lowcomms_addr(int nodeid, struct sockaddr_storage *addr, int len) |
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{ |
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struct sockaddr_storage *new_addr; |
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struct dlm_node_addr *new_node, *na; |
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bool ret; |
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|
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new_node = kzalloc(sizeof(struct dlm_node_addr), GFP_NOFS); |
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if (!new_node) |
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return -ENOMEM; |
|
|
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new_addr = kzalloc(sizeof(struct sockaddr_storage), GFP_NOFS); |
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if (!new_addr) { |
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kfree(new_node); |
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return -ENOMEM; |
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} |
|
|
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memcpy(new_addr, addr, len); |
|
|
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spin_lock(&dlm_node_addrs_spin); |
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na = find_node_addr(nodeid); |
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if (!na) { |
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new_node->nodeid = nodeid; |
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new_node->addr[0] = new_addr; |
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new_node->addr_count = 1; |
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new_node->mark = dlm_config.ci_mark; |
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list_add(&new_node->list, &dlm_node_addrs); |
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spin_unlock(&dlm_node_addrs_spin); |
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return 0; |
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} |
|
|
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ret = dlm_lowcomms_na_has_addr(na, addr); |
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if (ret) { |
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spin_unlock(&dlm_node_addrs_spin); |
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kfree(new_addr); |
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kfree(new_node); |
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return -EEXIST; |
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} |
|
|
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if (na->addr_count >= DLM_MAX_ADDR_COUNT) { |
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spin_unlock(&dlm_node_addrs_spin); |
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kfree(new_addr); |
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kfree(new_node); |
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return -ENOSPC; |
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} |
|
|
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na->addr[na->addr_count++] = new_addr; |
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spin_unlock(&dlm_node_addrs_spin); |
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kfree(new_node); |
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return 0; |
|
} |
|
|
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/* Data available on socket or listen socket received a connect */ |
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static void lowcomms_data_ready(struct sock *sk) |
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{ |
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struct connection *con; |
|
|
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con = sock2con(sk); |
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if (con && !test_and_set_bit(CF_READ_PENDING, &con->flags)) |
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queue_work(recv_workqueue, &con->rwork); |
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} |
|
|
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static void lowcomms_listen_data_ready(struct sock *sk) |
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{ |
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if (!dlm_allow_conn) |
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return; |
|
|
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queue_work(recv_workqueue, &listen_con.rwork); |
|
} |
|
|
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static void lowcomms_write_space(struct sock *sk) |
|
{ |
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struct connection *con; |
|
|
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con = sock2con(sk); |
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if (!con) |
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return; |
|
|
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if (!test_and_set_bit(CF_CONNECTED, &con->flags)) { |
|
log_print("connected to node %d", con->nodeid); |
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queue_work(send_workqueue, &con->swork); |
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return; |
|
} |
|
|
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clear_bit(SOCK_NOSPACE, &con->sock->flags); |
|
|
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if (test_and_clear_bit(CF_APP_LIMITED, &con->flags)) { |
|
con->sock->sk->sk_write_pending--; |
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clear_bit(SOCKWQ_ASYNC_NOSPACE, &con->sock->flags); |
|
} |
|
|
|
queue_work(send_workqueue, &con->swork); |
|
} |
|
|
|
static inline void lowcomms_connect_sock(struct connection *con) |
|
{ |
|
if (test_bit(CF_CLOSE, &con->flags)) |
|
return; |
|
queue_work(send_workqueue, &con->swork); |
|
cond_resched(); |
|
} |
|
|
|
static void lowcomms_state_change(struct sock *sk) |
|
{ |
|
/* SCTP layer is not calling sk_data_ready when the connection |
|
* is done, so we catch the signal through here. Also, it |
|
* doesn't switch socket state when entering shutdown, so we |
|
* skip the write in that case. |
|
*/ |
|
if (sk->sk_shutdown) { |
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if (sk->sk_shutdown == RCV_SHUTDOWN) |
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lowcomms_data_ready(sk); |
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} else if (sk->sk_state == TCP_ESTABLISHED) { |
|
lowcomms_write_space(sk); |
|
} |
|
} |
|
|
|
int dlm_lowcomms_connect_node(int nodeid) |
|
{ |
|
struct connection *con; |
|
int idx; |
|
|
|
if (nodeid == dlm_our_nodeid()) |
|
return 0; |
|
|
|
idx = srcu_read_lock(&connections_srcu); |
|
con = nodeid2con(nodeid, GFP_NOFS); |
|
if (!con) { |
|
srcu_read_unlock(&connections_srcu, idx); |
|
return -ENOMEM; |
|
} |
|
|
|
lowcomms_connect_sock(con); |
|
srcu_read_unlock(&connections_srcu, idx); |
|
|
|
return 0; |
|
} |
|
|
|
int dlm_lowcomms_nodes_set_mark(int nodeid, unsigned int mark) |
|
{ |
|
struct dlm_node_addr *na; |
|
|
|
spin_lock(&dlm_node_addrs_spin); |
|
na = find_node_addr(nodeid); |
|
if (!na) { |
|
spin_unlock(&dlm_node_addrs_spin); |
|
return -ENOENT; |
|
} |
|
|
|
na->mark = mark; |
|
spin_unlock(&dlm_node_addrs_spin); |
|
|
|
return 0; |
|
} |
|
|
|
static void lowcomms_error_report(struct sock *sk) |
|
{ |
|
struct connection *con; |
|
void (*orig_report)(struct sock *) = NULL; |
|
struct inet_sock *inet; |
|
|
|
con = sock2con(sk); |
|
if (con == NULL) |
|
goto out; |
|
|
|
orig_report = listen_sock.sk_error_report; |
|
|
|
inet = inet_sk(sk); |
|
switch (sk->sk_family) { |
|
case AF_INET: |
|
printk_ratelimited(KERN_ERR "dlm: node %d: socket error " |
|
"sending to node %d at %pI4, dport %d, " |
|
"sk_err=%d/%d\n", dlm_our_nodeid(), |
|
con->nodeid, &inet->inet_daddr, |
|
ntohs(inet->inet_dport), sk->sk_err, |
|
sk->sk_err_soft); |
|
break; |
|
#if IS_ENABLED(CONFIG_IPV6) |
|
case AF_INET6: |
|
printk_ratelimited(KERN_ERR "dlm: node %d: socket error " |
|
"sending to node %d at %pI6c, " |
|
"dport %d, sk_err=%d/%d\n", dlm_our_nodeid(), |
|
con->nodeid, &sk->sk_v6_daddr, |
|
ntohs(inet->inet_dport), sk->sk_err, |
|
sk->sk_err_soft); |
|
break; |
|
#endif |
|
default: |
|
printk_ratelimited(KERN_ERR "dlm: node %d: socket error " |
|
"invalid socket family %d set, " |
|
"sk_err=%d/%d\n", dlm_our_nodeid(), |
|
sk->sk_family, sk->sk_err, sk->sk_err_soft); |
|
goto out; |
|
} |
|
|
|
/* below sendcon only handling */ |
|
if (test_bit(CF_IS_OTHERCON, &con->flags)) |
|
con = con->sendcon; |
|
|
|
switch (sk->sk_err) { |
|
case ECONNREFUSED: |
|
set_bit(CF_DELAY_CONNECT, &con->flags); |
|
break; |
|
default: |
|
break; |
|
} |
|
|
|
if (!test_and_set_bit(CF_RECONNECT, &con->flags)) |
|
queue_work(send_workqueue, &con->swork); |
|
|
|
out: |
|
if (orig_report) |
|
orig_report(sk); |
|
} |
|
|
|
/* Note: sk_callback_lock must be locked before calling this function. */ |
|
static void save_listen_callbacks(struct socket *sock) |
|
{ |
|
struct sock *sk = sock->sk; |
|
|
|
listen_sock.sk_data_ready = sk->sk_data_ready; |
|
listen_sock.sk_state_change = sk->sk_state_change; |
|
listen_sock.sk_write_space = sk->sk_write_space; |
|
listen_sock.sk_error_report = sk->sk_error_report; |
|
} |
|
|
|
static void restore_callbacks(struct socket *sock) |
|
{ |
|
struct sock *sk = sock->sk; |
|
|
|
lock_sock(sk); |
|
sk->sk_user_data = NULL; |
|
sk->sk_data_ready = listen_sock.sk_data_ready; |
|
sk->sk_state_change = listen_sock.sk_state_change; |
|
sk->sk_write_space = listen_sock.sk_write_space; |
|
sk->sk_error_report = listen_sock.sk_error_report; |
|
release_sock(sk); |
|
} |
|
|
|
static void add_listen_sock(struct socket *sock, struct listen_connection *con) |
|
{ |
|
struct sock *sk = sock->sk; |
|
|
|
lock_sock(sk); |
|
save_listen_callbacks(sock); |
|
con->sock = sock; |
|
|
|
sk->sk_user_data = con; |
|
sk->sk_allocation = GFP_NOFS; |
|
/* Install a data_ready callback */ |
|
sk->sk_data_ready = lowcomms_listen_data_ready; |
|
release_sock(sk); |
|
} |
|
|
|
/* Make a socket active */ |
|
static void add_sock(struct socket *sock, struct connection *con) |
|
{ |
|
struct sock *sk = sock->sk; |
|
|
|
lock_sock(sk); |
|
con->sock = sock; |
|
|
|
sk->sk_user_data = con; |
|
/* Install a data_ready callback */ |
|
sk->sk_data_ready = lowcomms_data_ready; |
|
sk->sk_write_space = lowcomms_write_space; |
|
sk->sk_state_change = lowcomms_state_change; |
|
sk->sk_allocation = GFP_NOFS; |
|
sk->sk_error_report = lowcomms_error_report; |
|
release_sock(sk); |
|
} |
|
|
|
/* Add the port number to an IPv6 or 4 sockaddr and return the address |
|
length */ |
|
static void make_sockaddr(struct sockaddr_storage *saddr, uint16_t port, |
|
int *addr_len) |
|
{ |
|
saddr->ss_family = dlm_local_addr[0]->ss_family; |
|
if (saddr->ss_family == AF_INET) { |
|
struct sockaddr_in *in4_addr = (struct sockaddr_in *)saddr; |
|
in4_addr->sin_port = cpu_to_be16(port); |
|
*addr_len = sizeof(struct sockaddr_in); |
|
memset(&in4_addr->sin_zero, 0, sizeof(in4_addr->sin_zero)); |
|
} else { |
|
struct sockaddr_in6 *in6_addr = (struct sockaddr_in6 *)saddr; |
|
in6_addr->sin6_port = cpu_to_be16(port); |
|
*addr_len = sizeof(struct sockaddr_in6); |
|
} |
|
memset((char *)saddr + *addr_len, 0, sizeof(struct sockaddr_storage) - *addr_len); |
|
} |
|
|
|
static void dlm_page_release(struct kref *kref) |
|
{ |
|
struct writequeue_entry *e = container_of(kref, struct writequeue_entry, |
|
ref); |
|
|
|
__free_page(e->page); |
|
dlm_free_writequeue(e); |
|
} |
|
|
|
static void dlm_msg_release(struct kref *kref) |
|
{ |
|
struct dlm_msg *msg = container_of(kref, struct dlm_msg, ref); |
|
|
|
kref_put(&msg->entry->ref, dlm_page_release); |
|
dlm_free_msg(msg); |
|
} |
|
|
|
static void free_entry(struct writequeue_entry *e) |
|
{ |
|
struct dlm_msg *msg, *tmp; |
|
|
|
list_for_each_entry_safe(msg, tmp, &e->msgs, list) { |
|
if (msg->orig_msg) { |
|
msg->orig_msg->retransmit = false; |
|
kref_put(&msg->orig_msg->ref, dlm_msg_release); |
|
} |
|
|
|
list_del(&msg->list); |
|
kref_put(&msg->ref, dlm_msg_release); |
|
} |
|
|
|
list_del(&e->list); |
|
atomic_dec(&e->con->writequeue_cnt); |
|
kref_put(&e->ref, dlm_page_release); |
|
} |
|
|
|
static void dlm_close_sock(struct socket **sock) |
|
{ |
|
if (*sock) { |
|
restore_callbacks(*sock); |
|
sock_release(*sock); |
|
*sock = NULL; |
|
} |
|
} |
|
|
|
/* Close a remote connection and tidy up */ |
|
static void close_connection(struct connection *con, bool and_other, |
|
bool tx, bool rx) |
|
{ |
|
bool closing = test_and_set_bit(CF_CLOSING, &con->flags); |
|
struct writequeue_entry *e; |
|
|
|
if (tx && !closing && cancel_work_sync(&con->swork)) { |
|
log_print("canceled swork for node %d", con->nodeid); |
|
clear_bit(CF_WRITE_PENDING, &con->flags); |
|
} |
|
if (rx && !closing && cancel_work_sync(&con->rwork)) { |
|
log_print("canceled rwork for node %d", con->nodeid); |
|
clear_bit(CF_READ_PENDING, &con->flags); |
|
} |
|
|
|
mutex_lock(&con->sock_mutex); |
|
dlm_close_sock(&con->sock); |
|
|
|
if (con->othercon && and_other) { |
|
/* Will only re-enter once. */ |
|
close_connection(con->othercon, false, tx, rx); |
|
} |
|
|
|
/* if we send a writequeue entry only a half way, we drop the |
|
* whole entry because reconnection and that we not start of the |
|
* middle of a msg which will confuse the other end. |
|
* |
|
* we can always drop messages because retransmits, but what we |
|
* cannot allow is to transmit half messages which may be processed |
|
* at the other side. |
|
* |
|
* our policy is to start on a clean state when disconnects, we don't |
|
* know what's send/received on transport layer in this case. |
|
*/ |
|
spin_lock(&con->writequeue_lock); |
|
if (!list_empty(&con->writequeue)) { |
|
e = list_first_entry(&con->writequeue, struct writequeue_entry, |
|
list); |
|
if (e->dirty) |
|
free_entry(e); |
|
} |
|
spin_unlock(&con->writequeue_lock); |
|
|
|
con->rx_leftover = 0; |
|
con->retries = 0; |
|
clear_bit(CF_APP_LIMITED, &con->flags); |
|
clear_bit(CF_CONNECTED, &con->flags); |
|
clear_bit(CF_DELAY_CONNECT, &con->flags); |
|
clear_bit(CF_RECONNECT, &con->flags); |
|
clear_bit(CF_EOF, &con->flags); |
|
mutex_unlock(&con->sock_mutex); |
|
clear_bit(CF_CLOSING, &con->flags); |
|
} |
|
|
|
static void shutdown_connection(struct connection *con) |
|
{ |
|
int ret; |
|
|
|
flush_work(&con->swork); |
|
|
|
mutex_lock(&con->sock_mutex); |
|
/* nothing to shutdown */ |
|
if (!con->sock) { |
|
mutex_unlock(&con->sock_mutex); |
|
return; |
|
} |
|
|
|
set_bit(CF_SHUTDOWN, &con->flags); |
|
ret = kernel_sock_shutdown(con->sock, SHUT_WR); |
|
mutex_unlock(&con->sock_mutex); |
|
if (ret) { |
|
log_print("Connection %p failed to shutdown: %d will force close", |
|
con, ret); |
|
goto force_close; |
|
} else { |
|
ret = wait_event_timeout(con->shutdown_wait, |
|
!test_bit(CF_SHUTDOWN, &con->flags), |
|
DLM_SHUTDOWN_WAIT_TIMEOUT); |
|
if (ret == 0) { |
|
log_print("Connection %p shutdown timed out, will force close", |
|
con); |
|
goto force_close; |
|
} |
|
} |
|
|
|
return; |
|
|
|
force_close: |
|
clear_bit(CF_SHUTDOWN, &con->flags); |
|
close_connection(con, false, true, true); |
|
} |
|
|
|
static void dlm_tcp_shutdown(struct connection *con) |
|
{ |
|
if (con->othercon) |
|
shutdown_connection(con->othercon); |
|
shutdown_connection(con); |
|
} |
|
|
|
static int con_realloc_receive_buf(struct connection *con, int newlen) |
|
{ |
|
unsigned char *newbuf; |
|
|
|
newbuf = kmalloc(newlen, GFP_NOFS); |
|
if (!newbuf) |
|
return -ENOMEM; |
|
|
|
/* copy any leftover from last receive */ |
|
if (con->rx_leftover) |
|
memmove(newbuf, con->rx_buf, con->rx_leftover); |
|
|
|
/* swap to new buffer space */ |
|
kfree(con->rx_buf); |
|
con->rx_buflen = newlen; |
|
con->rx_buf = newbuf; |
|
|
|
return 0; |
|
} |
|
|
|
/* Data received from remote end */ |
|
static int receive_from_sock(struct connection *con) |
|
{ |
|
struct msghdr msg; |
|
struct kvec iov; |
|
int ret, buflen; |
|
|
|
mutex_lock(&con->sock_mutex); |
|
|
|
if (con->sock == NULL) { |
|
ret = -EAGAIN; |
|
goto out_close; |
|
} |
|
|
|
/* realloc if we get new buffer size to read out */ |
|
buflen = dlm_config.ci_buffer_size; |
|
if (con->rx_buflen != buflen && con->rx_leftover <= buflen) { |
|
ret = con_realloc_receive_buf(con, buflen); |
|
if (ret < 0) |
|
goto out_resched; |
|
} |
|
|
|
for (;;) { |
|
/* calculate new buffer parameter regarding last receive and |
|
* possible leftover bytes |
|
*/ |
|
iov.iov_base = con->rx_buf + con->rx_leftover; |
|
iov.iov_len = con->rx_buflen - con->rx_leftover; |
|
|
|
memset(&msg, 0, sizeof(msg)); |
|
msg.msg_flags = MSG_DONTWAIT | MSG_NOSIGNAL; |
|
ret = kernel_recvmsg(con->sock, &msg, &iov, 1, iov.iov_len, |
|
msg.msg_flags); |
|
trace_dlm_recv(con->nodeid, ret); |
|
if (ret == -EAGAIN) |
|
break; |
|
else if (ret <= 0) |
|
goto out_close; |
|
|
|
/* new buflen according readed bytes and leftover from last receive */ |
|
buflen = ret + con->rx_leftover; |
|
ret = dlm_process_incoming_buffer(con->nodeid, con->rx_buf, buflen); |
|
if (ret < 0) |
|
goto out_close; |
|
|
|
/* calculate leftover bytes from process and put it into begin of |
|
* the receive buffer, so next receive we have the full message |
|
* at the start address of the receive buffer. |
|
*/ |
|
con->rx_leftover = buflen - ret; |
|
if (con->rx_leftover) { |
|
memmove(con->rx_buf, con->rx_buf + ret, |
|
con->rx_leftover); |
|
} |
|
} |
|
|
|
dlm_midcomms_receive_done(con->nodeid); |
|
mutex_unlock(&con->sock_mutex); |
|
return 0; |
|
|
|
out_resched: |
|
if (!test_and_set_bit(CF_READ_PENDING, &con->flags)) |
|
queue_work(recv_workqueue, &con->rwork); |
|
mutex_unlock(&con->sock_mutex); |
|
return -EAGAIN; |
|
|
|
out_close: |
|
if (ret == 0) { |
|
log_print("connection %p got EOF from %d", |
|
con, con->nodeid); |
|
|
|
if (dlm_proto_ops->eof_condition && |
|
dlm_proto_ops->eof_condition(con)) { |
|
set_bit(CF_EOF, &con->flags); |
|
mutex_unlock(&con->sock_mutex); |
|
} else { |
|
mutex_unlock(&con->sock_mutex); |
|
close_connection(con, false, true, false); |
|
|
|
/* handling for tcp shutdown */ |
|
clear_bit(CF_SHUTDOWN, &con->flags); |
|
wake_up(&con->shutdown_wait); |
|
} |
|
|
|
/* signal to breaking receive worker */ |
|
ret = -1; |
|
} else { |
|
mutex_unlock(&con->sock_mutex); |
|
} |
|
return ret; |
|
} |
|
|
|
/* Listening socket is busy, accept a connection */ |
|
static int accept_from_sock(struct listen_connection *con) |
|
{ |
|
int result; |
|
struct sockaddr_storage peeraddr; |
|
struct socket *newsock; |
|
int len, idx; |
|
int nodeid; |
|
struct connection *newcon; |
|
struct connection *addcon; |
|
unsigned int mark; |
|
|
|
if (!con->sock) |
|
return -ENOTCONN; |
|
|
|
result = kernel_accept(con->sock, &newsock, O_NONBLOCK); |
|
if (result < 0) |
|
goto accept_err; |
|
|
|
/* Get the connected socket's peer */ |
|
memset(&peeraddr, 0, sizeof(peeraddr)); |
|
len = newsock->ops->getname(newsock, (struct sockaddr *)&peeraddr, 2); |
|
if (len < 0) { |
|
result = -ECONNABORTED; |
|
goto accept_err; |
|
} |
|
|
|
/* Get the new node's NODEID */ |
|
make_sockaddr(&peeraddr, 0, &len); |
|
if (addr_to_nodeid(&peeraddr, &nodeid, &mark)) { |
|
switch (peeraddr.ss_family) { |
|
case AF_INET: { |
|
struct sockaddr_in *sin = (struct sockaddr_in *)&peeraddr; |
|
|
|
log_print("connect from non cluster IPv4 node %pI4", |
|
&sin->sin_addr); |
|
break; |
|
} |
|
#if IS_ENABLED(CONFIG_IPV6) |
|
case AF_INET6: { |
|
struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)&peeraddr; |
|
|
|
log_print("connect from non cluster IPv6 node %pI6c", |
|
&sin6->sin6_addr); |
|
break; |
|
} |
|
#endif |
|
default: |
|
log_print("invalid family from non cluster node"); |
|
break; |
|
} |
|
|
|
sock_release(newsock); |
|
return -1; |
|
} |
|
|
|
log_print("got connection from %d", nodeid); |
|
|
|
/* Check to see if we already have a connection to this node. This |
|
* could happen if the two nodes initiate a connection at roughly |
|
* the same time and the connections cross on the wire. |
|
* In this case we store the incoming one in "othercon" |
|
*/ |
|
idx = srcu_read_lock(&connections_srcu); |
|
newcon = nodeid2con(nodeid, GFP_NOFS); |
|
if (!newcon) { |
|
srcu_read_unlock(&connections_srcu, idx); |
|
result = -ENOMEM; |
|
goto accept_err; |
|
} |
|
|
|
sock_set_mark(newsock->sk, mark); |
|
|
|
mutex_lock(&newcon->sock_mutex); |
|
if (newcon->sock) { |
|
struct connection *othercon = newcon->othercon; |
|
|
|
if (!othercon) { |
|
othercon = kzalloc(sizeof(*othercon), GFP_NOFS); |
|
if (!othercon) { |
|
log_print("failed to allocate incoming socket"); |
|
mutex_unlock(&newcon->sock_mutex); |
|
srcu_read_unlock(&connections_srcu, idx); |
|
result = -ENOMEM; |
|
goto accept_err; |
|
} |
|
|
|
result = dlm_con_init(othercon, nodeid); |
|
if (result < 0) { |
|
kfree(othercon); |
|
mutex_unlock(&newcon->sock_mutex); |
|
srcu_read_unlock(&connections_srcu, idx); |
|
goto accept_err; |
|
} |
|
|
|
lockdep_set_subclass(&othercon->sock_mutex, 1); |
|
set_bit(CF_IS_OTHERCON, &othercon->flags); |
|
newcon->othercon = othercon; |
|
othercon->sendcon = newcon; |
|
} else { |
|
/* close other sock con if we have something new */ |
|
close_connection(othercon, false, true, false); |
|
} |
|
|
|
mutex_lock(&othercon->sock_mutex); |
|
add_sock(newsock, othercon); |
|
addcon = othercon; |
|
mutex_unlock(&othercon->sock_mutex); |
|
} |
|
else { |
|
/* accept copies the sk after we've saved the callbacks, so we |
|
don't want to save them a second time or comm errors will |
|
result in calling sk_error_report recursively. */ |
|
add_sock(newsock, newcon); |
|
addcon = newcon; |
|
} |
|
|
|
set_bit(CF_CONNECTED, &addcon->flags); |
|
mutex_unlock(&newcon->sock_mutex); |
|
|
|
/* |
|
* Add it to the active queue in case we got data |
|
* between processing the accept adding the socket |
|
* to the read_sockets list |
|
*/ |
|
if (!test_and_set_bit(CF_READ_PENDING, &addcon->flags)) |
|
queue_work(recv_workqueue, &addcon->rwork); |
|
|
|
srcu_read_unlock(&connections_srcu, idx); |
|
|
|
return 0; |
|
|
|
accept_err: |
|
if (newsock) |
|
sock_release(newsock); |
|
|
|
if (result != -EAGAIN) |
|
log_print("error accepting connection from node: %d", result); |
|
return result; |
|
} |
|
|
|
/* |
|
* writequeue_entry_complete - try to delete and free write queue entry |
|
* @e: write queue entry to try to delete |
|
* @completed: bytes completed |
|
* |
|
* writequeue_lock must be held. |
|
*/ |
|
static void writequeue_entry_complete(struct writequeue_entry *e, int completed) |
|
{ |
|
e->offset += completed; |
|
e->len -= completed; |
|
/* signal that page was half way transmitted */ |
|
e->dirty = true; |
|
|
|
if (e->len == 0 && e->users == 0) |
|
free_entry(e); |
|
} |
|
|
|
/* |
|
* sctp_bind_addrs - bind a SCTP socket to all our addresses |
|
*/ |
|
static int sctp_bind_addrs(struct socket *sock, uint16_t port) |
|
{ |
|
struct sockaddr_storage localaddr; |
|
struct sockaddr *addr = (struct sockaddr *)&localaddr; |
|
int i, addr_len, result = 0; |
|
|
|
for (i = 0; i < dlm_local_count; i++) { |
|
memcpy(&localaddr, dlm_local_addr[i], sizeof(localaddr)); |
|
make_sockaddr(&localaddr, port, &addr_len); |
|
|
|
if (!i) |
|
result = kernel_bind(sock, addr, addr_len); |
|
else |
|
result = sock_bind_add(sock->sk, addr, addr_len); |
|
|
|
if (result < 0) { |
|
log_print("Can't bind to %d addr number %d, %d.\n", |
|
port, i + 1, result); |
|
break; |
|
} |
|
} |
|
return result; |
|
} |
|
|
|
/* Get local addresses */ |
|
static void init_local(void) |
|
{ |
|
struct sockaddr_storage sas, *addr; |
|
int i; |
|
|
|
dlm_local_count = 0; |
|
for (i = 0; i < DLM_MAX_ADDR_COUNT; i++) { |
|
if (dlm_our_addr(&sas, i)) |
|
break; |
|
|
|
addr = kmemdup(&sas, sizeof(*addr), GFP_NOFS); |
|
if (!addr) |
|
break; |
|
dlm_local_addr[dlm_local_count++] = addr; |
|
} |
|
} |
|
|
|
static void deinit_local(void) |
|
{ |
|
int i; |
|
|
|
for (i = 0; i < dlm_local_count; i++) |
|
kfree(dlm_local_addr[i]); |
|
} |
|
|
|
static struct writequeue_entry *new_writequeue_entry(struct connection *con) |
|
{ |
|
struct writequeue_entry *entry; |
|
|
|
entry = dlm_allocate_writequeue(); |
|
if (!entry) |
|
return NULL; |
|
|
|
entry->page = alloc_page(GFP_ATOMIC | __GFP_ZERO); |
|
if (!entry->page) { |
|
dlm_free_writequeue(entry); |
|
return NULL; |
|
} |
|
|
|
entry->offset = 0; |
|
entry->len = 0; |
|
entry->end = 0; |
|
entry->dirty = false; |
|
entry->con = con; |
|
entry->users = 1; |
|
kref_init(&entry->ref); |
|
return entry; |
|
} |
|
|
|
static struct writequeue_entry *new_wq_entry(struct connection *con, int len, |
|
char **ppc, void (*cb)(void *data), |
|
void *data) |
|
{ |
|
struct writequeue_entry *e; |
|
|
|
spin_lock(&con->writequeue_lock); |
|
if (!list_empty(&con->writequeue)) { |
|
e = list_last_entry(&con->writequeue, struct writequeue_entry, list); |
|
if (DLM_WQ_REMAIN_BYTES(e) >= len) { |
|
kref_get(&e->ref); |
|
|
|
*ppc = page_address(e->page) + e->end; |
|
if (cb) |
|
cb(data); |
|
|
|
e->end += len; |
|
e->users++; |
|
goto out; |
|
} |
|
} |
|
|
|
e = new_writequeue_entry(con); |
|
if (!e) |
|
goto out; |
|
|
|
kref_get(&e->ref); |
|
*ppc = page_address(e->page); |
|
e->end += len; |
|
atomic_inc(&con->writequeue_cnt); |
|
if (cb) |
|
cb(data); |
|
|
|
list_add_tail(&e->list, &con->writequeue); |
|
|
|
out: |
|
spin_unlock(&con->writequeue_lock); |
|
return e; |
|
}; |
|
|
|
static struct dlm_msg *dlm_lowcomms_new_msg_con(struct connection *con, int len, |
|
gfp_t allocation, char **ppc, |
|
void (*cb)(void *data), |
|
void *data) |
|
{ |
|
struct writequeue_entry *e; |
|
struct dlm_msg *msg; |
|
|
|
msg = dlm_allocate_msg(allocation); |
|
if (!msg) |
|
return NULL; |
|
|
|
kref_init(&msg->ref); |
|
|
|
e = new_wq_entry(con, len, ppc, cb, data); |
|
if (!e) { |
|
dlm_free_msg(msg); |
|
return NULL; |
|
} |
|
|
|
msg->retransmit = false; |
|
msg->orig_msg = NULL; |
|
msg->ppc = *ppc; |
|
msg->len = len; |
|
msg->entry = e; |
|
|
|
return msg; |
|
} |
|
|
|
/* avoid false positive for nodes_srcu, unlock happens in |
|
* dlm_lowcomms_commit_msg which is a must call if success |
|
*/ |
|
#ifndef __CHECKER__ |
|
struct dlm_msg *dlm_lowcomms_new_msg(int nodeid, int len, gfp_t allocation, |
|
char **ppc, void (*cb)(void *data), |
|
void *data) |
|
{ |
|
struct connection *con; |
|
struct dlm_msg *msg; |
|
int idx; |
|
|
|
if (len > DLM_MAX_SOCKET_BUFSIZE || |
|
len < sizeof(struct dlm_header)) { |
|
BUILD_BUG_ON(PAGE_SIZE < DLM_MAX_SOCKET_BUFSIZE); |
|
log_print("failed to allocate a buffer of size %d", len); |
|
WARN_ON(1); |
|
return NULL; |
|
} |
|
|
|
idx = srcu_read_lock(&connections_srcu); |
|
con = nodeid2con(nodeid, allocation); |
|
if (!con) { |
|
srcu_read_unlock(&connections_srcu, idx); |
|
return NULL; |
|
} |
|
|
|
msg = dlm_lowcomms_new_msg_con(con, len, allocation, ppc, cb, data); |
|
if (!msg) { |
|
srcu_read_unlock(&connections_srcu, idx); |
|
return NULL; |
|
} |
|
|
|
/* for dlm_lowcomms_commit_msg() */ |
|
kref_get(&msg->ref); |
|
/* we assume if successful commit must called */ |
|
msg->idx = idx; |
|
return msg; |
|
} |
|
#endif |
|
|
|
static void _dlm_lowcomms_commit_msg(struct dlm_msg *msg) |
|
{ |
|
struct writequeue_entry *e = msg->entry; |
|
struct connection *con = e->con; |
|
int users; |
|
|
|
spin_lock(&con->writequeue_lock); |
|
kref_get(&msg->ref); |
|
list_add(&msg->list, &e->msgs); |
|
|
|
users = --e->users; |
|
if (users) |
|
goto out; |
|
|
|
e->len = DLM_WQ_LENGTH_BYTES(e); |
|
spin_unlock(&con->writequeue_lock); |
|
|
|
queue_work(send_workqueue, &con->swork); |
|
return; |
|
|
|
out: |
|
spin_unlock(&con->writequeue_lock); |
|
return; |
|
} |
|
|
|
/* avoid false positive for nodes_srcu, lock was happen in |
|
* dlm_lowcomms_new_msg |
|
*/ |
|
#ifndef __CHECKER__ |
|
void dlm_lowcomms_commit_msg(struct dlm_msg *msg) |
|
{ |
|
_dlm_lowcomms_commit_msg(msg); |
|
srcu_read_unlock(&connections_srcu, msg->idx); |
|
/* because dlm_lowcomms_new_msg() */ |
|
kref_put(&msg->ref, dlm_msg_release); |
|
} |
|
#endif |
|
|
|
void dlm_lowcomms_put_msg(struct dlm_msg *msg) |
|
{ |
|
kref_put(&msg->ref, dlm_msg_release); |
|
} |
|
|
|
/* does not held connections_srcu, usage workqueue only */ |
|
int dlm_lowcomms_resend_msg(struct dlm_msg *msg) |
|
{ |
|
struct dlm_msg *msg_resend; |
|
char *ppc; |
|
|
|
if (msg->retransmit) |
|
return 1; |
|
|
|
msg_resend = dlm_lowcomms_new_msg_con(msg->entry->con, msg->len, |
|
GFP_ATOMIC, &ppc, NULL, NULL); |
|
if (!msg_resend) |
|
return -ENOMEM; |
|
|
|
msg->retransmit = true; |
|
kref_get(&msg->ref); |
|
msg_resend->orig_msg = msg; |
|
|
|
memcpy(ppc, msg->ppc, msg->len); |
|
_dlm_lowcomms_commit_msg(msg_resend); |
|
dlm_lowcomms_put_msg(msg_resend); |
|
|
|
return 0; |
|
} |
|
|
|
/* Send a message */ |
|
static void send_to_sock(struct connection *con) |
|
{ |
|
const int msg_flags = MSG_DONTWAIT | MSG_NOSIGNAL; |
|
struct writequeue_entry *e; |
|
int len, offset, ret; |
|
int count = 0; |
|
|
|
mutex_lock(&con->sock_mutex); |
|
if (con->sock == NULL) |
|
goto out_connect; |
|
|
|
spin_lock(&con->writequeue_lock); |
|
for (;;) { |
|
e = con_next_wq(con); |
|
if (!e) |
|
break; |
|
|
|
len = e->len; |
|
offset = e->offset; |
|
BUG_ON(len == 0 && e->users == 0); |
|
spin_unlock(&con->writequeue_lock); |
|
|
|
ret = kernel_sendpage(con->sock, e->page, offset, len, |
|
msg_flags); |
|
trace_dlm_send(con->nodeid, ret); |
|
if (ret == -EAGAIN || ret == 0) { |
|
if (ret == -EAGAIN && |
|
test_bit(SOCKWQ_ASYNC_NOSPACE, &con->sock->flags) && |
|
!test_and_set_bit(CF_APP_LIMITED, &con->flags)) { |
|
/* Notify TCP that we're limited by the |
|
* application window size. |
|
*/ |
|
set_bit(SOCK_NOSPACE, &con->sock->flags); |
|
con->sock->sk->sk_write_pending++; |
|
} |
|
cond_resched(); |
|
goto out; |
|
} else if (ret < 0) |
|
goto out; |
|
|
|
/* Don't starve people filling buffers */ |
|
if (++count >= MAX_SEND_MSG_COUNT) { |
|
cond_resched(); |
|
count = 0; |
|
} |
|
|
|
spin_lock(&con->writequeue_lock); |
|
writequeue_entry_complete(e, ret); |
|
} |
|
spin_unlock(&con->writequeue_lock); |
|
|
|
/* close if we got EOF */ |
|
if (test_and_clear_bit(CF_EOF, &con->flags)) { |
|
mutex_unlock(&con->sock_mutex); |
|
close_connection(con, false, false, true); |
|
|
|
/* handling for tcp shutdown */ |
|
clear_bit(CF_SHUTDOWN, &con->flags); |
|
wake_up(&con->shutdown_wait); |
|
} else { |
|
mutex_unlock(&con->sock_mutex); |
|
} |
|
|
|
return; |
|
|
|
out: |
|
mutex_unlock(&con->sock_mutex); |
|
return; |
|
|
|
out_connect: |
|
mutex_unlock(&con->sock_mutex); |
|
queue_work(send_workqueue, &con->swork); |
|
cond_resched(); |
|
} |
|
|
|
static void clean_one_writequeue(struct connection *con) |
|
{ |
|
struct writequeue_entry *e, *safe; |
|
|
|
spin_lock(&con->writequeue_lock); |
|
list_for_each_entry_safe(e, safe, &con->writequeue, list) { |
|
free_entry(e); |
|
} |
|
spin_unlock(&con->writequeue_lock); |
|
} |
|
|
|
/* Called from recovery when it knows that a node has |
|
left the cluster */ |
|
int dlm_lowcomms_close(int nodeid) |
|
{ |
|
struct connection *con; |
|
struct dlm_node_addr *na; |
|
int idx; |
|
|
|
log_print("closing connection to node %d", nodeid); |
|
idx = srcu_read_lock(&connections_srcu); |
|
con = nodeid2con(nodeid, 0); |
|
if (con) { |
|
set_bit(CF_CLOSE, &con->flags); |
|
close_connection(con, true, true, true); |
|
clean_one_writequeue(con); |
|
if (con->othercon) |
|
clean_one_writequeue(con->othercon); |
|
} |
|
srcu_read_unlock(&connections_srcu, idx); |
|
|
|
spin_lock(&dlm_node_addrs_spin); |
|
na = find_node_addr(nodeid); |
|
if (na) { |
|
list_del(&na->list); |
|
while (na->addr_count--) |
|
kfree(na->addr[na->addr_count]); |
|
kfree(na); |
|
} |
|
spin_unlock(&dlm_node_addrs_spin); |
|
|
|
return 0; |
|
} |
|
|
|
/* Receive workqueue function */ |
|
static void process_recv_sockets(struct work_struct *work) |
|
{ |
|
struct connection *con = container_of(work, struct connection, rwork); |
|
|
|
clear_bit(CF_READ_PENDING, &con->flags); |
|
receive_from_sock(con); |
|
} |
|
|
|
static void process_listen_recv_socket(struct work_struct *work) |
|
{ |
|
accept_from_sock(&listen_con); |
|
} |
|
|
|
static void dlm_connect(struct connection *con) |
|
{ |
|
struct sockaddr_storage addr; |
|
int result, addr_len; |
|
struct socket *sock; |
|
unsigned int mark; |
|
|
|
/* Some odd races can cause double-connects, ignore them */ |
|
if (con->retries++ > MAX_CONNECT_RETRIES) |
|
return; |
|
|
|
if (con->sock) { |
|
log_print("node %d already connected.", con->nodeid); |
|
return; |
|
} |
|
|
|
memset(&addr, 0, sizeof(addr)); |
|
result = nodeid_to_addr(con->nodeid, &addr, NULL, |
|
dlm_proto_ops->try_new_addr, &mark); |
|
if (result < 0) { |
|
log_print("no address for nodeid %d", con->nodeid); |
|
return; |
|
} |
|
|
|
/* Create a socket to communicate with */ |
|
result = sock_create_kern(&init_net, dlm_local_addr[0]->ss_family, |
|
SOCK_STREAM, dlm_proto_ops->proto, &sock); |
|
if (result < 0) |
|
goto socket_err; |
|
|
|
sock_set_mark(sock->sk, mark); |
|
dlm_proto_ops->sockopts(sock); |
|
|
|
add_sock(sock, con); |
|
|
|
result = dlm_proto_ops->bind(sock); |
|
if (result < 0) |
|
goto add_sock_err; |
|
|
|
log_print_ratelimited("connecting to %d", con->nodeid); |
|
make_sockaddr(&addr, dlm_config.ci_tcp_port, &addr_len); |
|
result = dlm_proto_ops->connect(con, sock, (struct sockaddr *)&addr, |
|
addr_len); |
|
if (result < 0) |
|
goto add_sock_err; |
|
|
|
return; |
|
|
|
add_sock_err: |
|
dlm_close_sock(&con->sock); |
|
|
|
socket_err: |
|
/* |
|
* Some errors are fatal and this list might need adjusting. For other |
|
* errors we try again until the max number of retries is reached. |
|
*/ |
|
if (result != -EHOSTUNREACH && |
|
result != -ENETUNREACH && |
|
result != -ENETDOWN && |
|
result != -EINVAL && |
|
result != -EPROTONOSUPPORT) { |
|
log_print("connect %d try %d error %d", con->nodeid, |
|
con->retries, result); |
|
msleep(1000); |
|
lowcomms_connect_sock(con); |
|
} |
|
} |
|
|
|
/* Send workqueue function */ |
|
static void process_send_sockets(struct work_struct *work) |
|
{ |
|
struct connection *con = container_of(work, struct connection, swork); |
|
|
|
WARN_ON(test_bit(CF_IS_OTHERCON, &con->flags)); |
|
|
|
clear_bit(CF_WRITE_PENDING, &con->flags); |
|
|
|
if (test_and_clear_bit(CF_RECONNECT, &con->flags)) { |
|
close_connection(con, false, false, true); |
|
dlm_midcomms_unack_msg_resend(con->nodeid); |
|
} |
|
|
|
if (con->sock == NULL) { |
|
if (test_and_clear_bit(CF_DELAY_CONNECT, &con->flags)) |
|
msleep(1000); |
|
|
|
mutex_lock(&con->sock_mutex); |
|
dlm_connect(con); |
|
mutex_unlock(&con->sock_mutex); |
|
} |
|
|
|
if (!list_empty(&con->writequeue)) |
|
send_to_sock(con); |
|
} |
|
|
|
static void work_stop(void) |
|
{ |
|
if (recv_workqueue) { |
|
destroy_workqueue(recv_workqueue); |
|
recv_workqueue = NULL; |
|
} |
|
|
|
if (send_workqueue) { |
|
destroy_workqueue(send_workqueue); |
|
send_workqueue = NULL; |
|
} |
|
} |
|
|
|
static int work_start(void) |
|
{ |
|
recv_workqueue = alloc_ordered_workqueue("dlm_recv", WQ_MEM_RECLAIM); |
|
if (!recv_workqueue) { |
|
log_print("can't start dlm_recv"); |
|
return -ENOMEM; |
|
} |
|
|
|
send_workqueue = alloc_ordered_workqueue("dlm_send", WQ_MEM_RECLAIM); |
|
if (!send_workqueue) { |
|
log_print("can't start dlm_send"); |
|
destroy_workqueue(recv_workqueue); |
|
recv_workqueue = NULL; |
|
return -ENOMEM; |
|
} |
|
|
|
return 0; |
|
} |
|
|
|
static void shutdown_conn(struct connection *con) |
|
{ |
|
if (dlm_proto_ops->shutdown_action) |
|
dlm_proto_ops->shutdown_action(con); |
|
} |
|
|
|
void dlm_lowcomms_shutdown(void) |
|
{ |
|
int idx; |
|
|
|
/* Set all the flags to prevent any |
|
* socket activity. |
|
*/ |
|
dlm_allow_conn = 0; |
|
|
|
if (recv_workqueue) |
|
flush_workqueue(recv_workqueue); |
|
if (send_workqueue) |
|
flush_workqueue(send_workqueue); |
|
|
|
dlm_close_sock(&listen_con.sock); |
|
|
|
idx = srcu_read_lock(&connections_srcu); |
|
foreach_conn(shutdown_conn); |
|
srcu_read_unlock(&connections_srcu, idx); |
|
} |
|
|
|
static void _stop_conn(struct connection *con, bool and_other) |
|
{ |
|
mutex_lock(&con->sock_mutex); |
|
set_bit(CF_CLOSE, &con->flags); |
|
set_bit(CF_READ_PENDING, &con->flags); |
|
set_bit(CF_WRITE_PENDING, &con->flags); |
|
if (con->sock && con->sock->sk) { |
|
lock_sock(con->sock->sk); |
|
con->sock->sk->sk_user_data = NULL; |
|
release_sock(con->sock->sk); |
|
} |
|
if (con->othercon && and_other) |
|
_stop_conn(con->othercon, false); |
|
mutex_unlock(&con->sock_mutex); |
|
} |
|
|
|
static void stop_conn(struct connection *con) |
|
{ |
|
_stop_conn(con, true); |
|
} |
|
|
|
static void connection_release(struct rcu_head *rcu) |
|
{ |
|
struct connection *con = container_of(rcu, struct connection, rcu); |
|
|
|
kfree(con->rx_buf); |
|
kfree(con); |
|
} |
|
|
|
static void free_conn(struct connection *con) |
|
{ |
|
close_connection(con, true, true, true); |
|
spin_lock(&connections_lock); |
|
hlist_del_rcu(&con->list); |
|
spin_unlock(&connections_lock); |
|
if (con->othercon) { |
|
clean_one_writequeue(con->othercon); |
|
call_srcu(&connections_srcu, &con->othercon->rcu, |
|
connection_release); |
|
} |
|
clean_one_writequeue(con); |
|
call_srcu(&connections_srcu, &con->rcu, connection_release); |
|
} |
|
|
|
static void work_flush(void) |
|
{ |
|
int ok; |
|
int i; |
|
struct connection *con; |
|
|
|
do { |
|
ok = 1; |
|
foreach_conn(stop_conn); |
|
if (recv_workqueue) |
|
flush_workqueue(recv_workqueue); |
|
if (send_workqueue) |
|
flush_workqueue(send_workqueue); |
|
for (i = 0; i < CONN_HASH_SIZE && ok; i++) { |
|
hlist_for_each_entry_rcu(con, &connection_hash[i], |
|
list) { |
|
ok &= test_bit(CF_READ_PENDING, &con->flags); |
|
ok &= test_bit(CF_WRITE_PENDING, &con->flags); |
|
if (con->othercon) { |
|
ok &= test_bit(CF_READ_PENDING, |
|
&con->othercon->flags); |
|
ok &= test_bit(CF_WRITE_PENDING, |
|
&con->othercon->flags); |
|
} |
|
} |
|
} |
|
} while (!ok); |
|
} |
|
|
|
void dlm_lowcomms_stop(void) |
|
{ |
|
int idx; |
|
|
|
idx = srcu_read_lock(&connections_srcu); |
|
work_flush(); |
|
foreach_conn(free_conn); |
|
srcu_read_unlock(&connections_srcu, idx); |
|
work_stop(); |
|
deinit_local(); |
|
|
|
dlm_proto_ops = NULL; |
|
} |
|
|
|
static int dlm_listen_for_all(void) |
|
{ |
|
struct socket *sock; |
|
int result; |
|
|
|
log_print("Using %s for communications", |
|
dlm_proto_ops->name); |
|
|
|
result = dlm_proto_ops->listen_validate(); |
|
if (result < 0) |
|
return result; |
|
|
|
result = sock_create_kern(&init_net, dlm_local_addr[0]->ss_family, |
|
SOCK_STREAM, dlm_proto_ops->proto, &sock); |
|
if (result < 0) { |
|
log_print("Can't create comms socket: %d", result); |
|
return result; |
|
} |
|
|
|
sock_set_mark(sock->sk, dlm_config.ci_mark); |
|
dlm_proto_ops->listen_sockopts(sock); |
|
|
|
result = dlm_proto_ops->listen_bind(sock); |
|
if (result < 0) |
|
goto out; |
|
|
|
save_listen_callbacks(sock); |
|
add_listen_sock(sock, &listen_con); |
|
|
|
INIT_WORK(&listen_con.rwork, process_listen_recv_socket); |
|
result = sock->ops->listen(sock, 5); |
|
if (result < 0) { |
|
dlm_close_sock(&listen_con.sock); |
|
goto out; |
|
} |
|
|
|
return 0; |
|
|
|
out: |
|
sock_release(sock); |
|
return result; |
|
} |
|
|
|
static int dlm_tcp_bind(struct socket *sock) |
|
{ |
|
struct sockaddr_storage src_addr; |
|
int result, addr_len; |
|
|
|
/* Bind to our cluster-known address connecting to avoid |
|
* routing problems. |
|
*/ |
|
memcpy(&src_addr, dlm_local_addr[0], sizeof(src_addr)); |
|
make_sockaddr(&src_addr, 0, &addr_len); |
|
|
|
result = sock->ops->bind(sock, (struct sockaddr *)&src_addr, |
|
addr_len); |
|
if (result < 0) { |
|
/* This *may* not indicate a critical error */ |
|
log_print("could not bind for connect: %d", result); |
|
} |
|
|
|
return 0; |
|
} |
|
|
|
static int dlm_tcp_connect(struct connection *con, struct socket *sock, |
|
struct sockaddr *addr, int addr_len) |
|
{ |
|
int ret; |
|
|
|
ret = sock->ops->connect(sock, addr, addr_len, O_NONBLOCK); |
|
switch (ret) { |
|
case -EINPROGRESS: |
|
fallthrough; |
|
case 0: |
|
return 0; |
|
} |
|
|
|
return ret; |
|
} |
|
|
|
static int dlm_tcp_listen_validate(void) |
|
{ |
|
/* We don't support multi-homed hosts */ |
|
if (dlm_local_count > 1) { |
|
log_print("TCP protocol can't handle multi-homed hosts, try SCTP"); |
|
return -EINVAL; |
|
} |
|
|
|
return 0; |
|
} |
|
|
|
static void dlm_tcp_sockopts(struct socket *sock) |
|
{ |
|
/* Turn off Nagle's algorithm */ |
|
tcp_sock_set_nodelay(sock->sk); |
|
} |
|
|
|
static void dlm_tcp_listen_sockopts(struct socket *sock) |
|
{ |
|
dlm_tcp_sockopts(sock); |
|
sock_set_reuseaddr(sock->sk); |
|
} |
|
|
|
static int dlm_tcp_listen_bind(struct socket *sock) |
|
{ |
|
int addr_len; |
|
|
|
/* Bind to our port */ |
|
make_sockaddr(dlm_local_addr[0], dlm_config.ci_tcp_port, &addr_len); |
|
return sock->ops->bind(sock, (struct sockaddr *)dlm_local_addr[0], |
|
addr_len); |
|
} |
|
|
|
static const struct dlm_proto_ops dlm_tcp_ops = { |
|
.name = "TCP", |
|
.proto = IPPROTO_TCP, |
|
.connect = dlm_tcp_connect, |
|
.sockopts = dlm_tcp_sockopts, |
|
.bind = dlm_tcp_bind, |
|
.listen_validate = dlm_tcp_listen_validate, |
|
.listen_sockopts = dlm_tcp_listen_sockopts, |
|
.listen_bind = dlm_tcp_listen_bind, |
|
.shutdown_action = dlm_tcp_shutdown, |
|
.eof_condition = tcp_eof_condition, |
|
}; |
|
|
|
static int dlm_sctp_bind(struct socket *sock) |
|
{ |
|
return sctp_bind_addrs(sock, 0); |
|
} |
|
|
|
static int dlm_sctp_connect(struct connection *con, struct socket *sock, |
|
struct sockaddr *addr, int addr_len) |
|
{ |
|
int ret; |
|
|
|
/* |
|
* Make sock->ops->connect() function return in specified time, |
|
* since O_NONBLOCK argument in connect() function does not work here, |
|
* then, we should restore the default value of this attribute. |
|
*/ |
|
sock_set_sndtimeo(sock->sk, 5); |
|
ret = sock->ops->connect(sock, addr, addr_len, 0); |
|
sock_set_sndtimeo(sock->sk, 0); |
|
if (ret < 0) |
|
return ret; |
|
|
|
if (!test_and_set_bit(CF_CONNECTED, &con->flags)) |
|
log_print("connected to node %d", con->nodeid); |
|
|
|
return 0; |
|
} |
|
|
|
static int dlm_sctp_listen_validate(void) |
|
{ |
|
if (!IS_ENABLED(CONFIG_IP_SCTP)) { |
|
log_print("SCTP is not enabled by this kernel"); |
|
return -EOPNOTSUPP; |
|
} |
|
|
|
request_module("sctp"); |
|
return 0; |
|
} |
|
|
|
static int dlm_sctp_bind_listen(struct socket *sock) |
|
{ |
|
return sctp_bind_addrs(sock, dlm_config.ci_tcp_port); |
|
} |
|
|
|
static void dlm_sctp_sockopts(struct socket *sock) |
|
{ |
|
/* Turn off Nagle's algorithm */ |
|
sctp_sock_set_nodelay(sock->sk); |
|
sock_set_rcvbuf(sock->sk, NEEDED_RMEM); |
|
} |
|
|
|
static const struct dlm_proto_ops dlm_sctp_ops = { |
|
.name = "SCTP", |
|
.proto = IPPROTO_SCTP, |
|
.try_new_addr = true, |
|
.connect = dlm_sctp_connect, |
|
.sockopts = dlm_sctp_sockopts, |
|
.bind = dlm_sctp_bind, |
|
.listen_validate = dlm_sctp_listen_validate, |
|
.listen_sockopts = dlm_sctp_sockopts, |
|
.listen_bind = dlm_sctp_bind_listen, |
|
}; |
|
|
|
int dlm_lowcomms_start(void) |
|
{ |
|
int error = -EINVAL; |
|
int i; |
|
|
|
for (i = 0; i < CONN_HASH_SIZE; i++) |
|
INIT_HLIST_HEAD(&connection_hash[i]); |
|
|
|
init_local(); |
|
if (!dlm_local_count) { |
|
error = -ENOTCONN; |
|
log_print("no local IP address has been set"); |
|
goto fail; |
|
} |
|
|
|
INIT_WORK(&listen_con.rwork, process_listen_recv_socket); |
|
|
|
error = work_start(); |
|
if (error) |
|
goto fail_local; |
|
|
|
dlm_allow_conn = 1; |
|
|
|
/* Start listening */ |
|
switch (dlm_config.ci_protocol) { |
|
case DLM_PROTO_TCP: |
|
dlm_proto_ops = &dlm_tcp_ops; |
|
break; |
|
case DLM_PROTO_SCTP: |
|
dlm_proto_ops = &dlm_sctp_ops; |
|
break; |
|
default: |
|
log_print("Invalid protocol identifier %d set", |
|
dlm_config.ci_protocol); |
|
error = -EINVAL; |
|
goto fail_proto_ops; |
|
} |
|
|
|
error = dlm_listen_for_all(); |
|
if (error) |
|
goto fail_listen; |
|
|
|
return 0; |
|
|
|
fail_listen: |
|
dlm_proto_ops = NULL; |
|
fail_proto_ops: |
|
dlm_allow_conn = 0; |
|
dlm_close_sock(&listen_con.sock); |
|
work_stop(); |
|
fail_local: |
|
deinit_local(); |
|
fail: |
|
return error; |
|
} |
|
|
|
void dlm_lowcomms_exit(void) |
|
{ |
|
struct dlm_node_addr *na, *safe; |
|
|
|
spin_lock(&dlm_node_addrs_spin); |
|
list_for_each_entry_safe(na, safe, &dlm_node_addrs, list) { |
|
list_del(&na->list); |
|
while (na->addr_count--) |
|
kfree(na->addr[na->addr_count]); |
|
kfree(na); |
|
} |
|
spin_unlock(&dlm_node_addrs_spin); |
|
}
|
|
|