diff --git a/drivers/acpi/acpi_ipmi.c b/drivers/acpi/acpi_ipmi.c index 9171a1a668f2..b285386eb37f 100644 --- a/drivers/acpi/acpi_ipmi.c +++ b/drivers/acpi/acpi_ipmi.c @@ -1,8 +1,9 @@ /* * acpi_ipmi.c - ACPI IPMI opregion * - * Copyright (C) 2010 Intel Corporation - * Copyright (C) 2010 Zhao Yakui + * Copyright (C) 2010, 2013 Intel Corporation + * Author: Zhao Yakui + * Lv Zheng * * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * @@ -67,6 +68,8 @@ struct acpi_ipmi_device { long curr_msgid; unsigned long flags; struct ipmi_smi_info smi_data; + bool dead; + struct kref kref; }; struct ipmi_driver_data { @@ -107,8 +110,8 @@ struct acpi_ipmi_buffer { static void ipmi_register_bmc(int iface, struct device *dev); static void ipmi_bmc_gone(int iface); static void ipmi_msg_handler(struct ipmi_recv_msg *msg, void *user_msg_data); -static void acpi_add_ipmi_device(struct acpi_ipmi_device *ipmi_device); -static void acpi_remove_ipmi_device(struct acpi_ipmi_device *ipmi_device); +static int ipmi_install_space_handler(struct acpi_ipmi_device *ipmi); +static void ipmi_remove_space_handler(struct acpi_ipmi_device *ipmi); static struct ipmi_driver_data driver_data = { .ipmi_devices = LIST_HEAD_INIT(driver_data.ipmi_devices), @@ -122,6 +125,88 @@ static struct ipmi_driver_data driver_data = { }, }; +static struct acpi_ipmi_device * +ipmi_dev_alloc(int iface, struct ipmi_smi_info *smi_data, acpi_handle handle) +{ + struct acpi_ipmi_device *ipmi_device; + int err; + ipmi_user_t user; + + ipmi_device = kzalloc(sizeof(*ipmi_device), GFP_KERNEL); + if (!ipmi_device) + return NULL; + + kref_init(&ipmi_device->kref); + INIT_LIST_HEAD(&ipmi_device->head); + INIT_LIST_HEAD(&ipmi_device->tx_msg_list); + spin_lock_init(&ipmi_device->tx_msg_lock); + + ipmi_device->handle = handle; + ipmi_device->pnp_dev = to_pnp_dev(get_device(smi_data->dev)); + memcpy(&ipmi_device->smi_data, smi_data, sizeof(struct ipmi_smi_info)); + ipmi_device->ipmi_ifnum = iface; + + err = ipmi_create_user(iface, &driver_data.ipmi_hndlrs, + ipmi_device, &user); + if (err) { + put_device(smi_data->dev); + kfree(ipmi_device); + return NULL; + } + ipmi_device->user_interface = user; + ipmi_install_space_handler(ipmi_device); + + return ipmi_device; +} + +static void ipmi_dev_release(struct acpi_ipmi_device *ipmi_device) +{ + ipmi_remove_space_handler(ipmi_device); + ipmi_destroy_user(ipmi_device->user_interface); + put_device(ipmi_device->smi_data.dev); + kfree(ipmi_device); +} + +static void ipmi_dev_release_kref(struct kref *kref) +{ + struct acpi_ipmi_device *ipmi = + container_of(kref, struct acpi_ipmi_device, kref); + + ipmi_dev_release(ipmi); +} + +static void __ipmi_dev_kill(struct acpi_ipmi_device *ipmi_device) +{ + list_del(&ipmi_device->head); + /* + * Always setting dead flag after deleting from the list or + * list_for_each_entry() codes must get changed. + */ + ipmi_device->dead = true; +} + +static struct acpi_ipmi_device *acpi_ipmi_dev_get(int iface) +{ + struct acpi_ipmi_device *temp, *ipmi_device = NULL; + + mutex_lock(&driver_data.ipmi_lock); + list_for_each_entry(temp, &driver_data.ipmi_devices, head) { + if (temp->ipmi_ifnum == iface) { + ipmi_device = temp; + kref_get(&ipmi_device->kref); + break; + } + } + mutex_unlock(&driver_data.ipmi_lock); + + return ipmi_device; +} + +static void acpi_ipmi_dev_put(struct acpi_ipmi_device *ipmi_device) +{ + kref_put(&ipmi_device->kref, ipmi_dev_release_kref); +} + static struct acpi_ipmi_msg *acpi_alloc_ipmi_msg(struct acpi_ipmi_device *ipmi) { struct acpi_ipmi_msg *ipmi_msg; @@ -220,25 +305,22 @@ static void acpi_format_ipmi_response(struct acpi_ipmi_msg *msg, static void ipmi_flush_tx_msg(struct acpi_ipmi_device *ipmi) { struct acpi_ipmi_msg *tx_msg, *temp; - int count = HZ / 10; - struct pnp_dev *pnp_dev = ipmi->pnp_dev; unsigned long flags; + /* + * NOTE: On-going ipmi_recv_msg + * ipmi_msg_handler() may still be invoked by ipmi_si after + * flushing. But it is safe to do a fast flushing on module_exit() + * without waiting for all ipmi_recv_msg(s) to complete from + * ipmi_msg_handler() as it is ensured by ipmi_si that all + * ipmi_recv_msg(s) are freed after invoking ipmi_destroy_user(). + */ spin_lock_irqsave(&ipmi->tx_msg_lock, flags); list_for_each_entry_safe(tx_msg, temp, &ipmi->tx_msg_list, head) { /* wake up the sleep thread on the Tx msg */ complete(&tx_msg->tx_complete); } spin_unlock_irqrestore(&ipmi->tx_msg_lock, flags); - - /* wait for about 100ms to flush the tx message list */ - while (count--) { - if (list_empty(&ipmi->tx_msg_list)) - break; - schedule_timeout(1); - } - if (!list_empty(&ipmi->tx_msg_list)) - dev_warn(&pnp_dev->dev, "tx msg list is not NULL\n"); } static void ipmi_msg_handler(struct ipmi_recv_msg *msg, void *user_msg_data) @@ -302,7 +384,6 @@ static void ipmi_register_bmc(int iface, struct device *dev) { struct acpi_ipmi_device *ipmi_device, *temp; struct pnp_dev *pnp_dev; - ipmi_user_t user; int err; struct ipmi_smi_info smi_data; acpi_handle handle; @@ -312,12 +393,18 @@ static void ipmi_register_bmc(int iface, struct device *dev) if (err) return; - if (smi_data.addr_src != SI_ACPI) { - put_device(smi_data.dev); - return; - } - + if (smi_data.addr_src != SI_ACPI) + goto err_ref; handle = smi_data.addr_info.acpi_info.acpi_handle; + if (!handle) + goto err_ref; + pnp_dev = to_pnp_dev(smi_data.dev); + + ipmi_device = ipmi_dev_alloc(iface, &smi_data, handle); + if (!ipmi_device) { + dev_warn(&pnp_dev->dev, "Can't create IPMI user interface\n"); + goto err_ref; + } mutex_lock(&driver_data.ipmi_lock); list_for_each_entry(temp, &driver_data.ipmi_devices, head) { @@ -326,34 +413,18 @@ static void ipmi_register_bmc(int iface, struct device *dev) * to the device list, don't add it again. */ if (temp->handle == handle) - goto out; + goto err_lock; } - ipmi_device = kzalloc(sizeof(*ipmi_device), GFP_KERNEL); - - if (!ipmi_device) - goto out; - - pnp_dev = to_pnp_dev(smi_data.dev); - ipmi_device->handle = handle; - ipmi_device->pnp_dev = pnp_dev; - - err = ipmi_create_user(iface, &driver_data.ipmi_hndlrs, - ipmi_device, &user); - if (err) { - dev_warn(&pnp_dev->dev, "Can't create IPMI user interface\n"); - kfree(ipmi_device); - goto out; - } - acpi_add_ipmi_device(ipmi_device); - ipmi_device->user_interface = user; - ipmi_device->ipmi_ifnum = iface; + list_add_tail(&ipmi_device->head, &driver_data.ipmi_devices); mutex_unlock(&driver_data.ipmi_lock); - memcpy(&ipmi_device->smi_data, &smi_data, sizeof(struct ipmi_smi_info)); + put_device(smi_data.dev); return; -out: +err_lock: mutex_unlock(&driver_data.ipmi_lock); + ipmi_dev_release(ipmi_device); +err_ref: put_device(smi_data.dev); return; } @@ -361,19 +432,22 @@ out: static void ipmi_bmc_gone(int iface) { struct acpi_ipmi_device *ipmi_device, *temp; + bool dev_found = false; mutex_lock(&driver_data.ipmi_lock); list_for_each_entry_safe(ipmi_device, temp, &driver_data.ipmi_devices, head) { - if (ipmi_device->ipmi_ifnum != iface) - continue; - - acpi_remove_ipmi_device(ipmi_device); - put_device(ipmi_device->smi_data.dev); - kfree(ipmi_device); - break; + if (ipmi_device->ipmi_ifnum != iface) { + dev_found = true; + __ipmi_dev_kill(ipmi_device); + break; + } } mutex_unlock(&driver_data.ipmi_lock); + if (dev_found) { + ipmi_flush_tx_msg(ipmi_device); + acpi_ipmi_dev_put(ipmi_device); + } } /* -------------------------------------------------------------------------- * Address Space Management @@ -397,7 +471,8 @@ acpi_ipmi_space_handler(u32 function, acpi_physical_address address, void *handler_context, void *region_context) { struct acpi_ipmi_msg *tx_msg; - struct acpi_ipmi_device *ipmi_device = handler_context; + int iface = (long)handler_context; + struct acpi_ipmi_device *ipmi_device; int err; acpi_status status; unsigned long flags; @@ -410,20 +485,31 @@ acpi_ipmi_space_handler(u32 function, acpi_physical_address address, if ((function & ACPI_IO_MASK) == ACPI_READ) return AE_TYPE; - if (!ipmi_device->user_interface) + ipmi_device = acpi_ipmi_dev_get(iface); + if (!ipmi_device) return AE_NOT_EXIST; tx_msg = acpi_alloc_ipmi_msg(ipmi_device); - if (!tx_msg) - return AE_NO_MEMORY; + if (!tx_msg) { + status = AE_NO_MEMORY; + goto out_ref; + } if (acpi_format_ipmi_request(tx_msg, address, value) != 0) { status = AE_TYPE; goto out_msg; } + mutex_lock(&driver_data.ipmi_lock); + /* Do not add a tx_msg that can not be flushed. */ + if (ipmi_device->dead) { + status = AE_NOT_EXIST; + mutex_unlock(&driver_data.ipmi_lock); + goto out_msg; + } spin_lock_irqsave(&ipmi_device->tx_msg_lock, flags); list_add_tail(&tx_msg->head, &ipmi_device->tx_msg_list); spin_unlock_irqrestore(&ipmi_device->tx_msg_lock, flags); + mutex_unlock(&driver_data.ipmi_lock); err = ipmi_request_settime(ipmi_device->user_interface, &tx_msg->addr, tx_msg->tx_msgid, @@ -443,6 +529,8 @@ out_list: spin_unlock_irqrestore(&ipmi_device->tx_msg_lock, flags); out_msg: kfree(tx_msg); +out_ref: + acpi_ipmi_dev_put(ipmi_device); return status; } @@ -465,9 +553,8 @@ static int ipmi_install_space_handler(struct acpi_ipmi_device *ipmi) return 0; status = acpi_install_address_space_handler(ipmi->handle, - ACPI_ADR_SPACE_IPMI, - &acpi_ipmi_space_handler, - NULL, ipmi); + ACPI_ADR_SPACE_IPMI, &acpi_ipmi_space_handler, + NULL, (void *)((long)ipmi->ipmi_ifnum)); if (ACPI_FAILURE(status)) { struct pnp_dev *pnp_dev = ipmi->pnp_dev; dev_warn(&pnp_dev->dev, "Can't register IPMI opregion space " @@ -478,36 +565,6 @@ static int ipmi_install_space_handler(struct acpi_ipmi_device *ipmi) return 0; } -static void acpi_add_ipmi_device(struct acpi_ipmi_device *ipmi_device) -{ - - INIT_LIST_HEAD(&ipmi_device->head); - - spin_lock_init(&ipmi_device->tx_msg_lock); - INIT_LIST_HEAD(&ipmi_device->tx_msg_list); - ipmi_install_space_handler(ipmi_device); - - list_add_tail(&ipmi_device->head, &driver_data.ipmi_devices); -} - -static void acpi_remove_ipmi_device(struct acpi_ipmi_device *ipmi_device) -{ - /* - * If the IPMI user interface is created, it should be - * destroyed. - */ - if (ipmi_device->user_interface) { - ipmi_destroy_user(ipmi_device->user_interface); - ipmi_device->user_interface = NULL; - } - /* flush the Tx_msg list */ - if (!list_empty(&ipmi_device->tx_msg_list)) - ipmi_flush_tx_msg(ipmi_device); - - list_del(&ipmi_device->head); - ipmi_remove_space_handler(ipmi_device); -} - static int __init acpi_ipmi_init(void) { int result = 0; @@ -524,7 +581,7 @@ static int __init acpi_ipmi_init(void) static void __exit acpi_ipmi_exit(void) { - struct acpi_ipmi_device *ipmi_device, *temp; + struct acpi_ipmi_device *ipmi_device; if (acpi_disabled) return; @@ -538,11 +595,17 @@ static void __exit acpi_ipmi_exit(void) * handler and free it. */ mutex_lock(&driver_data.ipmi_lock); - list_for_each_entry_safe(ipmi_device, temp, - &driver_data.ipmi_devices, head) { - acpi_remove_ipmi_device(ipmi_device); - put_device(ipmi_device->smi_data.dev); - kfree(ipmi_device); + while (!list_empty(&driver_data.ipmi_devices)) { + ipmi_device = list_first_entry(&driver_data.ipmi_devices, + struct acpi_ipmi_device, + head); + __ipmi_dev_kill(ipmi_device); + mutex_unlock(&driver_data.ipmi_lock); + + ipmi_flush_tx_msg(ipmi_device); + acpi_ipmi_dev_put(ipmi_device); + + mutex_lock(&driver_data.ipmi_lock); } mutex_unlock(&driver_data.ipmi_lock); }