From 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 Mon Sep 17 00:00:00 2001 From: Yunhong Jiang Date: Tue, 4 Aug 2015 12:17:53 -0700 Subject: Add the rt linux 4.1.3-rt3 as base Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang --- kernel/drivers/s390/cio/qdio_thinint.c | 299 +++++++++++++++++++++++++++++++++ 1 file changed, 299 insertions(+) create mode 100644 kernel/drivers/s390/cio/qdio_thinint.c (limited to 'kernel/drivers/s390/cio/qdio_thinint.c') diff --git a/kernel/drivers/s390/cio/qdio_thinint.c b/kernel/drivers/s390/cio/qdio_thinint.c new file mode 100644 index 000000000..5d06253c2 --- /dev/null +++ b/kernel/drivers/s390/cio/qdio_thinint.c @@ -0,0 +1,299 @@ +/* + * Copyright IBM Corp. 2000, 2009 + * Author(s): Utz Bacher + * Cornelia Huck + * Jan Glauber + */ +#include +#include +#include +#include +#include +#include +#include +#include + +#include "cio.h" +#include "ioasm.h" +#include "qdio.h" +#include "qdio_debug.h" + +/* + * Restriction: only 63 iqdio subchannels would have its own indicator, + * after that, subsequent subchannels share one indicator + */ +#define TIQDIO_NR_NONSHARED_IND 63 +#define TIQDIO_NR_INDICATORS (TIQDIO_NR_NONSHARED_IND + 1) +#define TIQDIO_SHARED_IND 63 + +/* device state change indicators */ +struct indicator_t { + u32 ind; /* u32 because of compare-and-swap performance */ + atomic_t count; /* use count, 0 or 1 for non-shared indicators */ +}; + +/* list of thin interrupt input queues */ +static LIST_HEAD(tiq_list); +static DEFINE_MUTEX(tiq_list_lock); + +/* Adapter interrupt definitions */ +static void tiqdio_thinint_handler(struct airq_struct *airq); + +static struct airq_struct tiqdio_airq = { + .handler = tiqdio_thinint_handler, + .isc = QDIO_AIRQ_ISC, +}; + +static struct indicator_t *q_indicators; + +u64 last_ai_time; + +/* returns addr for the device state change indicator */ +static u32 *get_indicator(void) +{ + int i; + + for (i = 0; i < TIQDIO_NR_NONSHARED_IND; i++) + if (!atomic_read(&q_indicators[i].count)) { + atomic_set(&q_indicators[i].count, 1); + return &q_indicators[i].ind; + } + + /* use the shared indicator */ + atomic_inc(&q_indicators[TIQDIO_SHARED_IND].count); + return &q_indicators[TIQDIO_SHARED_IND].ind; +} + +static void put_indicator(u32 *addr) +{ + int i; + + if (!addr) + return; + i = ((unsigned long)addr - (unsigned long)q_indicators) / + sizeof(struct indicator_t); + atomic_dec(&q_indicators[i].count); +} + +void tiqdio_add_input_queues(struct qdio_irq *irq_ptr) +{ + mutex_lock(&tiq_list_lock); + list_add_rcu(&irq_ptr->input_qs[0]->entry, &tiq_list); + mutex_unlock(&tiq_list_lock); + xchg(irq_ptr->dsci, 1 << 7); +} + +void tiqdio_remove_input_queues(struct qdio_irq *irq_ptr) +{ + struct qdio_q *q; + + q = irq_ptr->input_qs[0]; + /* if establish triggered an error */ + if (!q || !q->entry.prev || !q->entry.next) + return; + + mutex_lock(&tiq_list_lock); + list_del_rcu(&q->entry); + mutex_unlock(&tiq_list_lock); + synchronize_rcu(); +} + +static inline int has_multiple_inq_on_dsci(struct qdio_irq *irq_ptr) +{ + return irq_ptr->nr_input_qs > 1; +} + +static inline int references_shared_dsci(struct qdio_irq *irq_ptr) +{ + return irq_ptr->dsci == &q_indicators[TIQDIO_SHARED_IND].ind; +} + +static inline int shared_ind(struct qdio_irq *irq_ptr) +{ + return references_shared_dsci(irq_ptr) || + has_multiple_inq_on_dsci(irq_ptr); +} + +void clear_nonshared_ind(struct qdio_irq *irq_ptr) +{ + if (!is_thinint_irq(irq_ptr)) + return; + if (shared_ind(irq_ptr)) + return; + xchg(irq_ptr->dsci, 0); +} + +int test_nonshared_ind(struct qdio_irq *irq_ptr) +{ + if (!is_thinint_irq(irq_ptr)) + return 0; + if (shared_ind(irq_ptr)) + return 0; + if (*irq_ptr->dsci) + return 1; + else + return 0; +} + +static inline u32 clear_shared_ind(void) +{ + if (!atomic_read(&q_indicators[TIQDIO_SHARED_IND].count)) + return 0; + return xchg(&q_indicators[TIQDIO_SHARED_IND].ind, 0); +} + +static inline void tiqdio_call_inq_handlers(struct qdio_irq *irq) +{ + struct qdio_q *q; + int i; + + for_each_input_queue(irq, q, i) { + if (!references_shared_dsci(irq) && + has_multiple_inq_on_dsci(irq)) + xchg(q->irq_ptr->dsci, 0); + + if (q->u.in.queue_start_poll) { + /* skip if polling is enabled or already in work */ + if (test_and_set_bit(QDIO_QUEUE_IRQS_DISABLED, + &q->u.in.queue_irq_state)) { + qperf_inc(q, int_discarded); + continue; + } + + /* avoid dsci clear here, done after processing */ + q->u.in.queue_start_poll(q->irq_ptr->cdev, q->nr, + q->irq_ptr->int_parm); + } else { + if (!shared_ind(q->irq_ptr)) + xchg(q->irq_ptr->dsci, 0); + + /* + * Call inbound processing but not directly + * since that could starve other thinint queues. + */ + tasklet_schedule(&q->tasklet); + } + } +} + +/** + * tiqdio_thinint_handler - thin interrupt handler for qdio + * @alsi: pointer to adapter local summary indicator + * @data: NULL + */ +static void tiqdio_thinint_handler(struct airq_struct *airq) +{ + u32 si_used = clear_shared_ind(); + struct qdio_q *q; + + last_ai_time = S390_lowcore.int_clock; + inc_irq_stat(IRQIO_QAI); + + /* protect tiq_list entries, only changed in activate or shutdown */ + rcu_read_lock(); + + /* check for work on all inbound thinint queues */ + list_for_each_entry_rcu(q, &tiq_list, entry) { + struct qdio_irq *irq; + + /* only process queues from changed sets */ + irq = q->irq_ptr; + if (unlikely(references_shared_dsci(irq))) { + if (!si_used) + continue; + } else if (!*irq->dsci) + continue; + + tiqdio_call_inq_handlers(irq); + + qperf_inc(q, adapter_int); + } + rcu_read_unlock(); +} + +static int set_subchannel_ind(struct qdio_irq *irq_ptr, int reset) +{ + struct chsc_scssc_area *scssc = (void *)irq_ptr->chsc_page; + u64 summary_indicator_addr, subchannel_indicator_addr; + int rc; + + if (reset) { + summary_indicator_addr = 0; + subchannel_indicator_addr = 0; + } else { + summary_indicator_addr = virt_to_phys(tiqdio_airq.lsi_ptr); + subchannel_indicator_addr = virt_to_phys(irq_ptr->dsci); + } + + rc = chsc_sadc(irq_ptr->schid, scssc, summary_indicator_addr, + subchannel_indicator_addr); + if (rc) { + DBF_ERROR("%4x SSI r:%4x", irq_ptr->schid.sch_no, + scssc->response.code); + goto out; + } + + DBF_EVENT("setscind"); + DBF_HEX(&summary_indicator_addr, sizeof(summary_indicator_addr)); + DBF_HEX(&subchannel_indicator_addr, sizeof(subchannel_indicator_addr)); +out: + return rc; +} + +/* allocate non-shared indicators and shared indicator */ +int __init tiqdio_allocate_memory(void) +{ + q_indicators = kzalloc(sizeof(struct indicator_t) * TIQDIO_NR_INDICATORS, + GFP_KERNEL); + if (!q_indicators) + return -ENOMEM; + return 0; +} + +void tiqdio_free_memory(void) +{ + kfree(q_indicators); +} + +int __init tiqdio_register_thinints(void) +{ + int rc; + + rc = register_adapter_interrupt(&tiqdio_airq); + if (rc) { + DBF_EVENT("RTI:%x", rc); + return rc; + } + return 0; +} + +int qdio_establish_thinint(struct qdio_irq *irq_ptr) +{ + if (!is_thinint_irq(irq_ptr)) + return 0; + return set_subchannel_ind(irq_ptr, 0); +} + +void qdio_setup_thinint(struct qdio_irq *irq_ptr) +{ + if (!is_thinint_irq(irq_ptr)) + return; + irq_ptr->dsci = get_indicator(); + DBF_HEX(&irq_ptr->dsci, sizeof(void *)); +} + +void qdio_shutdown_thinint(struct qdio_irq *irq_ptr) +{ + if (!is_thinint_irq(irq_ptr)) + return; + + /* reset adapter interrupt indicators */ + set_subchannel_ind(irq_ptr, 1); + put_indicator(irq_ptr->dsci); +} + +void __exit tiqdio_unregister_thinints(void) +{ + WARN_ON(!list_empty(&tiq_list)); + unregister_adapter_interrupt(&tiqdio_airq); +} -- cgit 1.2.3-korg