diff options
Diffstat (limited to 'arch/powerpc')
-rw-r--r-- | arch/powerpc/platforms/powernv/opal-async.c | 92 |
1 files changed, 51 insertions, 41 deletions
diff --git a/arch/powerpc/platforms/powernv/opal-async.c b/arch/powerpc/platforms/powernv/opal-async.c index 64255d3ee14a..a8a57310759a 100644 --- a/arch/powerpc/platforms/powernv/opal-async.c +++ b/arch/powerpc/platforms/powernv/opal-async.c @@ -1,7 +1,7 @@ /* * PowerNV OPAL asynchronous completion interfaces * - * Copyright 2013 IBM Corp. + * Copyright 2013-2017 IBM Corp. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License @@ -23,40 +23,47 @@ #include <asm/machdep.h> #include <asm/opal.h> -#define N_ASYNC_COMPLETIONS 64 +enum opal_async_token_state { + ASYNC_TOKEN_UNALLOCATED = 0, + ASYNC_TOKEN_ALLOCATED, + ASYNC_TOKEN_COMPLETED +}; + +struct opal_async_token { + enum opal_async_token_state state; + struct opal_msg response; +}; -static DECLARE_BITMAP(opal_async_complete_map, N_ASYNC_COMPLETIONS) = {~0UL}; -static DECLARE_BITMAP(opal_async_token_map, N_ASYNC_COMPLETIONS); static DECLARE_WAIT_QUEUE_HEAD(opal_async_wait); static DEFINE_SPINLOCK(opal_async_comp_lock); static struct semaphore opal_async_sem; -static struct opal_msg *opal_async_responses; static unsigned int opal_max_async_tokens; +static struct opal_async_token *opal_async_tokens; static int __opal_async_get_token(void) { unsigned long flags; - int token; + int i, token = -EBUSY; spin_lock_irqsave(&opal_async_comp_lock, flags); - token = find_first_zero_bit(opal_async_token_map, opal_max_async_tokens); - if (token >= opal_max_async_tokens) { - token = -EBUSY; - goto out; - } - if (!__test_and_clear_bit(token, opal_async_complete_map)) { - token = -EBUSY; - goto out; + for (i = 0; i < opal_max_async_tokens; i++) { + if (opal_async_tokens[i].state == ASYNC_TOKEN_UNALLOCATED) { + opal_async_tokens[i].state = ASYNC_TOKEN_ALLOCATED; + token = i; + break; + } } - __set_bit(token, opal_async_token_map); - -out: spin_unlock_irqrestore(&opal_async_comp_lock, flags); return token; } +/* + * Note: If the returned token is used in an opal call and opal returns + * OPAL_ASYNC_COMPLETION you MUST call opal_async_wait_response() before + * calling another other opal_async_* function + */ int opal_async_get_token_interruptible(void) { int token; @@ -76,6 +83,7 @@ EXPORT_SYMBOL_GPL(opal_async_get_token_interruptible); static int __opal_async_release_token(int token) { unsigned long flags; + int rc; if (token < 0 || token >= opal_max_async_tokens) { pr_err("%s: Passed token is out of range, token %d\n", @@ -84,11 +92,18 @@ static int __opal_async_release_token(int token) } spin_lock_irqsave(&opal_async_comp_lock, flags); - __set_bit(token, opal_async_complete_map); - __clear_bit(token, opal_async_token_map); + switch (opal_async_tokens[token].state) { + case ASYNC_TOKEN_COMPLETED: + case ASYNC_TOKEN_ALLOCATED: + opal_async_tokens[token].state = ASYNC_TOKEN_UNALLOCATED; + rc = 0; + break; + default: + rc = 1; + } spin_unlock_irqrestore(&opal_async_comp_lock, flags); - return 0; + return rc; } int opal_async_release_token(int token) @@ -96,12 +111,10 @@ int opal_async_release_token(int token) int ret; ret = __opal_async_release_token(token); - if (ret) - return ret; - - up(&opal_async_sem); + if (!ret) + up(&opal_async_sem); - return 0; + return ret; } EXPORT_SYMBOL_GPL(opal_async_release_token); @@ -122,13 +135,15 @@ int opal_async_wait_response(uint64_t token, struct opal_msg *msg) * functional. */ opal_wake_poller(); - wait_event(opal_async_wait, test_bit(token, opal_async_complete_map)); - memcpy(msg, &opal_async_responses[token], sizeof(*msg)); + wait_event(opal_async_wait, opal_async_tokens[token].state + == ASYNC_TOKEN_COMPLETED); + memcpy(msg, &opal_async_tokens[token].response, sizeof(*msg)); return 0; } EXPORT_SYMBOL_GPL(opal_async_wait_response); +/* Called from interrupt context */ static int opal_async_comp_event(struct notifier_block *nb, unsigned long msg_type, void *msg) { @@ -140,9 +155,9 @@ static int opal_async_comp_event(struct notifier_block *nb, return 0; token = be64_to_cpu(comp_msg->params[0]); - memcpy(&opal_async_responses[token], comp_msg, sizeof(*comp_msg)); + memcpy(&opal_async_tokens[token].response, comp_msg, sizeof(*comp_msg)); spin_lock_irqsave(&opal_async_comp_lock, flags); - __set_bit(token, opal_async_complete_map); + opal_async_tokens[token].state = ASYNC_TOKEN_COMPLETED; spin_unlock_irqrestore(&opal_async_comp_lock, flags); wake_up(&opal_async_wait); @@ -178,24 +193,19 @@ int __init opal_async_comp_init(void) } opal_max_async_tokens = be32_to_cpup(async); - if (opal_max_async_tokens > N_ASYNC_COMPLETIONS) - opal_max_async_tokens = N_ASYNC_COMPLETIONS; + opal_async_tokens = kcalloc(opal_max_async_tokens, + sizeof(*opal_async_tokens), GFP_KERNEL); + if (!opal_async_tokens) { + err = -ENOMEM; + goto out_opal_node; + } err = opal_message_notifier_register(OPAL_MSG_ASYNC_COMP, &opal_async_comp_nb); if (err) { pr_err("%s: Can't register OPAL event notifier (%d)\n", __func__, err); - goto out_opal_node; - } - - opal_async_responses = kzalloc( - sizeof(*opal_async_responses) * opal_max_async_tokens, - GFP_KERNEL); - if (!opal_async_responses) { - pr_err("%s: Out of memory, failed to do asynchronous " - "completion init\n", __func__); - err = -ENOMEM; + kfree(opal_async_tokens); goto out_opal_node; } |