diff options
author | Deb McLemore <debmc@linux.vnet.ibm.com> | 2018-05-20 21:04:38 -0500 |
---|---|---|
committer | Michael Ellerman <mpe@ellerman.id.au> | 2019-10-11 19:42:06 +1100 |
commit | a9336ddf448b1cba3080195cec2287af3907236c (patch) | |
tree | 2402d97e43add5b95dc10166ada0a4d6d8fced11 /arch/powerpc/platforms/powernv/opal.c | |
parent | 29674a1c71be710f8418468aa6a8addd6d1aba1c (diff) | |
download | linux-a9336ddf448b1cba3080195cec2287af3907236c.tar.bz2 |
powerpc/powernv: Add queue mechanism for early messages
When issuing a BMC soft poweroff during IPL, the poweroff can be lost
so the machine would not poweroff.
This is because opal messages can be received before the opal-power
code registered its notifiers.
Fix it by buffering messages. If we receive a message and do not yet
have a handler for that type, store the message and replay when a
handler for that type is registered.
Signed-off-by: Deb McLemore <debmc@linux.vnet.ibm.com>
[mpe: Single unlock path in opal_message_notifier_register(), tweak
comments/formatting and change log.]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1526868278-4204-1-git-send-email-debmc@linux.vnet.ibm.com
Diffstat (limited to 'arch/powerpc/platforms/powernv/opal.c')
-rw-r--r-- | arch/powerpc/platforms/powernv/opal.c | 86 |
1 files changed, 84 insertions, 2 deletions
diff --git a/arch/powerpc/platforms/powernv/opal.c b/arch/powerpc/platforms/powernv/opal.c index 38e90270280b..b1d064842da4 100644 --- a/arch/powerpc/platforms/powernv/opal.c +++ b/arch/powerpc/platforms/powernv/opal.c @@ -35,6 +35,16 @@ #include "powernv.h" +#define OPAL_MSG_QUEUE_MAX 16 + +struct opal_msg_node { + struct list_head list; + struct opal_msg msg; +}; + +static DEFINE_SPINLOCK(msg_list_lock); +static LIST_HEAD(msg_list); + /* /sys/firmware/opal */ struct kobject *opal_kobj; @@ -50,6 +60,8 @@ struct mcheck_recoverable_range { u64 recover_addr; }; +static int msg_list_size; + static struct mcheck_recoverable_range *mc_recoverable_range; static int mc_recoverable_range_len; @@ -237,6 +249,43 @@ static int __init opal_register_exception_handlers(void) } machine_early_initcall(powernv, opal_register_exception_handlers); +static void queue_replay_msg(void *msg) +{ + struct opal_msg_node *msg_node; + + if (msg_list_size < OPAL_MSG_QUEUE_MAX) { + msg_node = kzalloc(sizeof(*msg_node), GFP_ATOMIC); + if (msg_node) { + INIT_LIST_HEAD(&msg_node->list); + memcpy(&msg_node->msg, msg, sizeof(struct opal_msg)); + list_add_tail(&msg_node->list, &msg_list); + msg_list_size++; + } else + pr_warn_once("message queue no memory\n"); + + if (msg_list_size >= OPAL_MSG_QUEUE_MAX) + pr_warn_once("message queue full\n"); + } +} + +static void dequeue_replay_msg(enum opal_msg_type msg_type) +{ + struct opal_msg_node *msg_node, *tmp; + + list_for_each_entry_safe(msg_node, tmp, &msg_list, list) { + if (be32_to_cpu(msg_node->msg.msg_type) != msg_type) + continue; + + atomic_notifier_call_chain(&opal_msg_notifier_head[msg_type], + msg_type, + &msg_node->msg); + + list_del(&msg_node->list); + kfree(msg_node); + msg_list_size--; + } +} + /* * Opal message notifier based on message type. Allow subscribers to get * notified for specific messgae type. @@ -244,14 +293,30 @@ machine_early_initcall(powernv, opal_register_exception_handlers); int opal_message_notifier_register(enum opal_msg_type msg_type, struct notifier_block *nb) { + int ret; + unsigned long flags; + if (!nb || msg_type >= OPAL_MSG_TYPE_MAX) { pr_warn("%s: Invalid arguments, msg_type:%d\n", __func__, msg_type); return -EINVAL; } - return atomic_notifier_chain_register( - &opal_msg_notifier_head[msg_type], nb); + spin_lock_irqsave(&msg_list_lock, flags); + ret = atomic_notifier_chain_register( + &opal_msg_notifier_head[msg_type], nb); + + /* + * If the registration succeeded, replay any queued messages that came + * in prior to the notifier chain registration. msg_list_lock held here + * to ensure they're delivered prior to any subsequent messages. + */ + if (ret == 0) + dequeue_replay_msg(msg_type); + + spin_unlock_irqrestore(&msg_list_lock, flags); + + return ret; } EXPORT_SYMBOL_GPL(opal_message_notifier_register); @@ -265,6 +330,23 @@ EXPORT_SYMBOL_GPL(opal_message_notifier_unregister); static void opal_message_do_notify(uint32_t msg_type, void *msg) { + unsigned long flags; + bool queued = false; + + spin_lock_irqsave(&msg_list_lock, flags); + if (opal_msg_notifier_head[msg_type].head == NULL) { + /* + * Queue up the msg since no notifiers have registered + * yet for this msg_type. + */ + queue_replay_msg(msg); + queued = true; + } + spin_unlock_irqrestore(&msg_list_lock, flags); + + if (queued) + return; + /* notify subscribers */ atomic_notifier_call_chain(&opal_msg_notifier_head[msg_type], msg_type, msg); |