/* * Support for adapter interruptions * * Copyright IBM Corp. 1999, 2007 * Author(s): Ingo Adlung * Cornelia Huck * Arnd Bergmann * Peter Oberparleiter */ #include #include #include #include #include #include #include #include #include #include "cio.h" #include "cio_debug.h" #include "ioasm.h" static DEFINE_SPINLOCK(airq_lists_lock); static struct hlist_head airq_lists[MAX_ISC+1]; /** * register_adapter_interrupt() - register adapter interrupt handler * @airq: pointer to adapter interrupt descriptor * * Returns 0 on success, or -EINVAL. */ int register_adapter_interrupt(struct airq_struct *airq) { char dbf_txt[32]; if (!airq->handler || airq->isc > MAX_ISC) return -EINVAL; if (!airq->lsi_ptr) { airq->lsi_ptr = kzalloc(1, GFP_KERNEL); if (!airq->lsi_ptr) return -ENOMEM; airq->flags |= AIRQ_PTR_ALLOCATED; } if (!airq->lsi_mask) airq->lsi_mask = 0xff; snprintf(dbf_txt, sizeof(dbf_txt), "rairq:%p", airq); CIO_TRACE_EVENT(4, dbf_txt); isc_register(airq->isc); spin_lock(&airq_lists_lock); hlist_add_head_rcu(&airq->list, &airq_lists[airq->isc]); spin_unlock(&airq_lists_lock); return 0; } EXPORT_SYMBOL(register_adapter_interrupt); /** * unregister_adapter_interrupt - unregister adapter interrupt handler * @airq: pointer to adapter interrupt descriptor */ void unregister_adapter_interrupt(struct airq_struct *airq) { char dbf_txt[32]; if (hlist_unhashed(&airq->list)) return; snprintf(dbf_txt, sizeof(dbf_txt), "urairq:%p", airq); CIO_TRACE_EVENT(4, dbf_txt); spin_lock(&airq_lists_lock); hlist_del_rcu(&airq->list); spin_unlock(&airq_lists_lock); synchronize_rcu(); isc_unregister(airq->isc); if (airq->flags & AIRQ_PTR_ALLOCATED) { kfree(airq->lsi_ptr); airq->lsi_ptr = NULL; airq->flags &= ~AIRQ_PTR_ALLOCATED; } } EXPORT_SYMBOL(unregister_adapter_interrupt); static irqreturn_t do_airq_interrupt(int irq, void *dummy) { struct tpi_info *tpi_info; struct airq_struct *airq; struct hlist_head *head; __this_cpu_write(s390_idle.nohz_delay, 1); tpi_info = (struct tpi_info *) &get_irq_regs()->int_code; head = &airq_lists[tpi_info->isc]; rcu_read_lock(); hlist_for_each_entry_rcu(airq, head, list) if ((*airq->lsi_ptr & airq->lsi_mask) != 0) airq->handler(airq); rcu_read_unlock(); return IRQ_HANDLED; } static struct irqaction airq_interrupt = { .name = "AIO", .handler = do_airq_interrupt, }; void __init init_airq_interrupts(void) { irq_set_chip_and_handler(THIN_INTERRUPT, &dummy_irq_chip, handle_percpu_irq); setup_irq(THIN_INTERRUPT, &airq_interrupt); } /** * airq_iv_create - create an interrupt vector * @bits: number of bits in the interrupt vector * @flags: allocation flags * * Returns a pointer to an interrupt vector structure */ struct airq_iv *airq_iv_create(unsigned long bits, unsigned long flags) { struct airq_iv *iv; unsigned long size; iv = kzalloc(sizeof(*iv), GFP_KERNEL); if (!iv) goto out; iv->bits = bits; size = BITS_TO_LONGS(bits) * sizeof(unsigned long); iv->vector = kzalloc(size, GFP_KERNEL); if (!iv->vector) goto out_free; if (flags & AIRQ_IV_ALLOC) { iv->avail = kmalloc(size, GFP_KERNEL); if (!iv->avail) goto out_free; memset(iv->avail, 0xff, size); iv->end = 0; } else iv->end = bits; if (flags & AIRQ_IV_BITLOCK) { iv->bitlock = kzalloc(size, GFP_KERNEL); if (!iv->bitlock) goto out_free; } if (flags & AIRQ_IV_PTR) { size = bits * sizeof(unsigned long); iv->ptr = kzalloc(size, GFP_KERNEL); if (!iv->ptr) goto out_free; } if (flags & AIRQ_IV_DATA) { size = bits * sizeof(unsigned int); iv->data = kzalloc(size, GFP_KERNEL); if (!iv->data) goto out_free; } spin_lock_init(&iv->lock); return iv; out_free: kfree(iv->ptr); kfree(iv->bitlock); kfree(iv->avail); kfree(iv->vector); kfree(iv); out: return NULL; } EXPORT_SYMBOL(airq_iv_create); /** * airq_iv_release - release an interrupt vector * @iv: pointer to interrupt vector structure */ void airq_iv_release(struct airq_iv *iv) { kfree(iv->data); kfree(iv->ptr); kfree(iv->bitlock); kfree(iv->vector); kfree(iv->avail); kfree(iv); } EXPORT_SYMBOL(airq_iv_release); /** * airq_iv_alloc_bit - allocate an irq bit from an interrupt vector * @iv: pointer to an interrupt vector structure * * Returns the bit number of the allocated irq, or -1UL if no bit * is available or the AIRQ_IV_ALLOC flag has not been specified */ unsigned long airq_iv_alloc_bit(struct airq_iv *iv) { unsigned long bit; if (!iv->avail) return -1UL; spin_lock(&iv->lock); bit = find_first_bit_inv(iv->avail, iv->bits); if (bit < iv->bits) { clear_bit_inv(bit, iv->avail); if (bit >= iv->end) iv->end = bit + 1; } else bit = -1UL; spin_unlock(&iv->lock); return bit; } EXPORT_SYMBOL(airq_iv_alloc_bit); /** * airq_iv_free_bit - free an irq bit of an interrupt vector * @iv: pointer to interrupt vector structure * @bit: number of the irq bit to free */ void airq_iv_free_bit(struct airq_iv *iv, unsigned long bit) { if (!iv->avail) return; spin_lock(&iv->lock); /* Clear (possibly left over) interrupt bit */ clear_bit_inv(bit, iv->vector); /* Make the bit position available again */ set_bit_inv(bit, iv->avail); if (bit == iv->end - 1) { /* Find new end of bit-field */ while (--iv->end > 0) if (!test_bit_inv(iv->end - 1, iv->avail)) break; } spin_unlock(&iv->lock); } EXPORT_SYMBOL(airq_iv_free_bit); /** * airq_iv_scan - scan interrupt vector for non-zero bits * @iv: pointer to interrupt vector structure * @start: bit number to start the search * @end: bit number to end the search * * Returns the bit number of the next non-zero interrupt bit, or * -1UL if the scan completed without finding any more any non-zero bits. */ unsigned long airq_iv_scan(struct airq_iv *iv, unsigned long start, unsigned long end) { unsigned long bit; /* Find non-zero bit starting from 'ivs->next'. */ bit = find_next_bit_inv(iv->vector, end, start); if (bit >= end) return -1UL; clear_bit_inv(bit, iv->vector); return bit; } EXPORT_SYMBOL(airq_iv_scan);