diff options
Diffstat (limited to 'drivers/char/ipmi/ipmi_msghandler.c')
-rw-r--r-- | drivers/char/ipmi/ipmi_msghandler.c | 126 |
1 files changed, 107 insertions, 19 deletions
diff --git a/drivers/char/ipmi/ipmi_msghandler.c b/drivers/char/ipmi/ipmi_msghandler.c index c59265146e9c..49a1707693c9 100644 --- a/drivers/char/ipmi/ipmi_msghandler.c +++ b/drivers/char/ipmi/ipmi_msghandler.c @@ -11,8 +11,8 @@ * Copyright 2002 MontaVista Software Inc. */ -#define pr_fmt(fmt) "%s" fmt, "IPMI message handler: " -#define dev_fmt pr_fmt +#define pr_fmt(fmt) "IPMI message handler: " fmt +#define dev_fmt(fmt) pr_fmt(fmt) #include <linux/module.h> #include <linux/errno.h> @@ -145,6 +145,18 @@ module_param(default_max_retries, uint, 0644); MODULE_PARM_DESC(default_max_retries, "The time (milliseconds) between retry sends in maintenance mode"); +/* The default maximum number of users that may register. */ +static unsigned int max_users = 30; +module_param(max_users, uint, 0644); +MODULE_PARM_DESC(max_users, + "The most users that may use the IPMI stack at one time."); + +/* The default maximum number of message a user may have outstanding. */ +static unsigned int max_msgs_per_user = 100; +module_param(max_msgs_per_user, uint, 0644); +MODULE_PARM_DESC(max_msgs_per_user, + "The most message a user may have outstanding."); + /* Call every ~1000 ms. */ #define IPMI_TIMEOUT_TIME 1000 @@ -187,6 +199,8 @@ struct ipmi_user { /* Does this interface receive IPMI events? */ bool gets_events; + atomic_t nr_msgs; + /* Free must run in process context for RCU cleanup. */ struct work_struct remove_work; }; @@ -442,6 +456,10 @@ struct ipmi_smi { */ struct list_head users; struct srcu_struct users_srcu; + atomic_t nr_users; + struct device_attribute nr_users_devattr; + struct device_attribute nr_msgs_devattr; + /* Used for wake ups at startup. */ wait_queue_head_t waitq; @@ -718,12 +736,6 @@ static void intf_free(struct kref *ref) kfree(intf); } -struct watcher_entry { - int intf_num; - struct ipmi_smi *intf; - struct list_head link; -}; - int ipmi_smi_watcher_register(struct ipmi_smi_watcher *watcher) { struct ipmi_smi *intf; @@ -927,11 +939,13 @@ static int deliver_response(struct ipmi_smi *intf, struct ipmi_recv_msg *msg) * risk. At this moment, simply skip it in that case. */ ipmi_free_recv_msg(msg); + atomic_dec(&msg->user->nr_msgs); } else { int index; struct ipmi_user *user = acquire_ipmi_user(msg->user, &index); if (user) { + atomic_dec(&user->nr_msgs); user->handler->ipmi_recv_hndl(msg, user->handler_data); release_ipmi_user(user, index); } else { @@ -1230,6 +1244,11 @@ int ipmi_create_user(unsigned int if_num, goto out_kfree; found: + if (atomic_add_return(1, &intf->nr_users) > max_users) { + rv = -EBUSY; + goto out_kfree; + } + INIT_WORK(&new_user->remove_work, free_user_work); rv = init_srcu_struct(&new_user->release_barrier); @@ -1244,6 +1263,7 @@ int ipmi_create_user(unsigned int if_num, /* Note that each existing user holds a refcount to the interface. */ kref_get(&intf->refcount); + atomic_set(&new_user->nr_msgs, 0); kref_init(&new_user->refcount); new_user->handler = handler; new_user->handler_data = handler_data; @@ -1262,6 +1282,7 @@ int ipmi_create_user(unsigned int if_num, return 0; out_kfree: + atomic_dec(&intf->nr_users); srcu_read_unlock(&ipmi_interfaces_srcu, index); vfree(new_user); return rv; @@ -1336,6 +1357,7 @@ static void _ipmi_destroy_user(struct ipmi_user *user) /* Remove the user from the interface's sequence table. */ spin_lock_irqsave(&intf->seq_lock, flags); list_del_rcu(&user->link); + atomic_dec(&intf->nr_users); for (i = 0; i < IPMI_IPMB_NUM_SEQ; i++) { if (intf->seq_table[i].inuse @@ -2284,6 +2306,14 @@ static int i_ipmi_request(struct ipmi_user *user, struct ipmi_recv_msg *recv_msg; int rv = 0; + if (user) { + if (atomic_add_return(1, &user->nr_msgs) > max_msgs_per_user) { + /* Decrement will happen at the end of the routine. */ + rv = -EBUSY; + goto out; + } + } + if (supplied_recv) recv_msg = supplied_recv; else { @@ -2296,7 +2326,7 @@ static int i_ipmi_request(struct ipmi_user *user, recv_msg->user_msg_data = user_msg_data; if (supplied_smi) - smi_msg = (struct ipmi_smi_msg *) supplied_smi; + smi_msg = supplied_smi; else { smi_msg = ipmi_alloc_smi_msg(); if (smi_msg == NULL) { @@ -2348,13 +2378,16 @@ out_err: ipmi_free_smi_msg(smi_msg); ipmi_free_recv_msg(recv_msg); } else { - pr_debug("Send: %*ph\n", smi_msg->data_size, smi_msg->data); + dev_dbg(intf->si_dev, "Send: %*ph\n", + smi_msg->data_size, smi_msg->data); smi_send(intf, intf->handlers, smi_msg, priority); } rcu_read_unlock(); out: + if (rv && user) + atomic_dec(&user->nr_msgs); return rv; } @@ -3471,6 +3504,36 @@ void ipmi_poll_interface(struct ipmi_user *user) } EXPORT_SYMBOL(ipmi_poll_interface); +static ssize_t nr_users_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct ipmi_smi *intf = container_of(attr, + struct ipmi_smi, nr_users_devattr); + + return sysfs_emit(buf, "%d\n", atomic_read(&intf->nr_users)); +} +static DEVICE_ATTR_RO(nr_users); + +static ssize_t nr_msgs_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct ipmi_smi *intf = container_of(attr, + struct ipmi_smi, nr_msgs_devattr); + struct ipmi_user *user; + int index; + unsigned int count = 0; + + index = srcu_read_lock(&intf->users_srcu); + list_for_each_entry_rcu(user, &intf->users, link) + count += atomic_read(&user->nr_msgs); + srcu_read_unlock(&intf->users_srcu, index); + + return sysfs_emit(buf, "%u\n", count); +} +static DEVICE_ATTR_RO(nr_msgs); + static void redo_bmc_reg(struct work_struct *work) { struct ipmi_smi *intf = container_of(work, struct ipmi_smi, @@ -3529,6 +3592,7 @@ int ipmi_add_smi(struct module *owner, if (slave_addr != 0) intf->addrinfo[0].address = slave_addr; INIT_LIST_HEAD(&intf->users); + atomic_set(&intf->nr_users, 0); intf->handlers = handlers; intf->send_info = send_info; spin_lock_init(&intf->seq_lock); @@ -3592,6 +3656,20 @@ int ipmi_add_smi(struct module *owner, if (rv) goto out_err_bmc_reg; + intf->nr_users_devattr = dev_attr_nr_users; + sysfs_attr_init(&intf->nr_users_devattr.attr); + rv = device_create_file(intf->si_dev, &intf->nr_users_devattr); + if (rv) + goto out_err_bmc_reg; + + intf->nr_msgs_devattr = dev_attr_nr_msgs; + sysfs_attr_init(&intf->nr_msgs_devattr.attr); + rv = device_create_file(intf->si_dev, &intf->nr_msgs_devattr); + if (rv) { + device_remove_file(intf->si_dev, &intf->nr_users_devattr); + goto out_err_bmc_reg; + } + /* * Keep memory order straight for RCU readers. Make * sure everything else is committed to memory before @@ -3677,8 +3755,11 @@ static void cleanup_smi_msgs(struct ipmi_smi *intf) void ipmi_unregister_smi(struct ipmi_smi *intf) { struct ipmi_smi_watcher *w; - int intf_num = intf->intf_num, index; + int intf_num, index; + if (!intf) + return; + intf_num = intf->intf_num; mutex_lock(&ipmi_interfaces_mutex); intf->intf_num = -1; intf->in_shutdown = true; @@ -3688,6 +3769,9 @@ void ipmi_unregister_smi(struct ipmi_smi *intf) /* At this point no users can be added to the interface. */ + device_remove_file(intf->si_dev, &intf->nr_msgs_devattr); + device_remove_file(intf->si_dev, &intf->nr_users_devattr); + /* * Call all the watcher interfaces to tell them that * an interface is going away. @@ -3836,7 +3920,8 @@ static int handle_ipmb_get_msg_cmd(struct ipmi_smi *intf, msg->data[10] = ipmb_checksum(&msg->data[6], 4); msg->data_size = 11; - pr_debug("Invalid command: %*ph\n", msg->data_size, msg->data); + dev_dbg(intf->si_dev, "Invalid command: %*ph\n", + msg->data_size, msg->data); rcu_read_lock(); if (!intf->in_shutdown) { @@ -3989,10 +4074,10 @@ static int handle_ipmb_direct_rcv_rsp(struct ipmi_smi *intf, struct ipmi_recv_msg *recv_msg; struct ipmi_ipmb_direct_addr *daddr; - recv_msg = (struct ipmi_recv_msg *) msg->user_data; + recv_msg = msg->user_data; if (recv_msg == NULL) { dev_warn(intf->si_dev, - "IPMI message received with no owner. This could be because of a malformed message, or because of a hardware error. Contact your hardware vendor for assistance.\n"); + "IPMI direct message received with no owner. This could be because of a malformed message, or because of a hardware error. Contact your hardware vendor for assistance.\n"); return 0; } @@ -4266,7 +4351,7 @@ static int handle_oem_get_msg_cmd(struct ipmi_smi *intf, /* * The message starts at byte 4 which follows the - * the Channel Byte in the "GET MESSAGE" command + * Channel Byte in the "GET MESSAGE" command */ recv_msg->msg.data_len = msg->rsp_size - 4; memcpy(recv_msg->msg_data, &msg->rsp[4], @@ -4407,10 +4492,10 @@ static int handle_bmc_rsp(struct ipmi_smi *intf, struct ipmi_recv_msg *recv_msg; struct ipmi_system_interface_addr *smi_addr; - recv_msg = (struct ipmi_recv_msg *) msg->user_data; + recv_msg = msg->user_data; if (recv_msg == NULL) { dev_warn(intf->si_dev, - "IPMI message received with no owner. This could be because of a malformed message, or because of a hardware error. Contact your hardware vendor for assistance.\n"); + "IPMI SMI message received with no owner. This could be because of a malformed message, or because of a hardware error. Contact your hardware vendor for assistance.\n"); return 0; } @@ -4444,7 +4529,7 @@ static int handle_one_recv_msg(struct ipmi_smi *intf, unsigned char cc; bool is_cmd = !((msg->rsp[0] >> 2) & 1); - pr_debug("Recv: %*ph\n", msg->rsp_size, msg->rsp); + dev_dbg(intf->si_dev, "Recv: %*ph\n", msg->rsp_size, msg->rsp); if (msg->rsp_size < 2) { /* Message is too small to be correct. */ @@ -4518,6 +4603,8 @@ return_unspecified: } else /* The message was sent, start the timer. */ intf_start_seq_timer(intf, msg->msgid); + requeue = 0; + goto out; } else if (((msg->rsp[0] >> 2) != ((msg->data[0] >> 2) | 1)) || (msg->rsp[1] != msg->data[1])) { /* @@ -4826,7 +4913,8 @@ smi_from_recv_msg(struct ipmi_smi *intf, struct ipmi_recv_msg *recv_msg, smi_msg->data_size = recv_msg->msg.data_len; smi_msg->msgid = STORE_SEQ_IN_MSGID(seq, seqid); - pr_debug("Resend: %*ph\n", smi_msg->data_size, smi_msg->data); + dev_dbg(intf->si_dev, "Resend: %*ph\n", + smi_msg->data_size, smi_msg->data); return smi_msg; } |