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path: root/drivers/iommu/iova.c
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Diffstat (limited to 'drivers/iommu/iova.c')
-rw-r--r--drivers/iommu/iova.c183
1 files changed, 183 insertions, 0 deletions
diff --git a/drivers/iommu/iova.c b/drivers/iommu/iova.c
index 246f14c83944..33edfa794ae9 100644
--- a/drivers/iommu/iova.c
+++ b/drivers/iommu/iova.c
@@ -32,6 +32,8 @@ static unsigned long iova_rcache_get(struct iova_domain *iovad,
unsigned long limit_pfn);
static void init_iova_rcaches(struct iova_domain *iovad);
static void free_iova_rcaches(struct iova_domain *iovad);
+static void fq_destroy_all_entries(struct iova_domain *iovad);
+static void fq_flush_timeout(unsigned long data);
void
init_iova_domain(struct iova_domain *iovad, unsigned long granule,
@@ -50,10 +52,61 @@ init_iova_domain(struct iova_domain *iovad, unsigned long granule,
iovad->granule = granule;
iovad->start_pfn = start_pfn;
iovad->dma_32bit_pfn = pfn_32bit + 1;
+ iovad->flush_cb = NULL;
+ iovad->fq = NULL;
init_iova_rcaches(iovad);
}
EXPORT_SYMBOL_GPL(init_iova_domain);
+static void free_iova_flush_queue(struct iova_domain *iovad)
+{
+ if (!iovad->fq)
+ return;
+
+ if (timer_pending(&iovad->fq_timer))
+ del_timer(&iovad->fq_timer);
+
+ fq_destroy_all_entries(iovad);
+
+ free_percpu(iovad->fq);
+
+ iovad->fq = NULL;
+ iovad->flush_cb = NULL;
+ iovad->entry_dtor = NULL;
+}
+
+int init_iova_flush_queue(struct iova_domain *iovad,
+ iova_flush_cb flush_cb, iova_entry_dtor entry_dtor)
+{
+ int cpu;
+
+ atomic64_set(&iovad->fq_flush_start_cnt, 0);
+ atomic64_set(&iovad->fq_flush_finish_cnt, 0);
+
+ iovad->fq = alloc_percpu(struct iova_fq);
+ if (!iovad->fq)
+ return -ENOMEM;
+
+ iovad->flush_cb = flush_cb;
+ iovad->entry_dtor = entry_dtor;
+
+ for_each_possible_cpu(cpu) {
+ struct iova_fq *fq;
+
+ fq = per_cpu_ptr(iovad->fq, cpu);
+ fq->head = 0;
+ fq->tail = 0;
+
+ spin_lock_init(&fq->lock);
+ }
+
+ setup_timer(&iovad->fq_timer, fq_flush_timeout, (unsigned long)iovad);
+ atomic_set(&iovad->fq_timer_on, 0);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(init_iova_flush_queue);
+
static struct rb_node *
__get_cached_rbnode(struct iova_domain *iovad, unsigned long *limit_pfn)
{
@@ -423,6 +476,135 @@ free_iova_fast(struct iova_domain *iovad, unsigned long pfn, unsigned long size)
}
EXPORT_SYMBOL_GPL(free_iova_fast);
+#define fq_ring_for_each(i, fq) \
+ for ((i) = (fq)->head; (i) != (fq)->tail; (i) = ((i) + 1) % IOVA_FQ_SIZE)
+
+static inline bool fq_full(struct iova_fq *fq)
+{
+ assert_spin_locked(&fq->lock);
+ return (((fq->tail + 1) % IOVA_FQ_SIZE) == fq->head);
+}
+
+static inline unsigned fq_ring_add(struct iova_fq *fq)
+{
+ unsigned idx = fq->tail;
+
+ assert_spin_locked(&fq->lock);
+
+ fq->tail = (idx + 1) % IOVA_FQ_SIZE;
+
+ return idx;
+}
+
+static void fq_ring_free(struct iova_domain *iovad, struct iova_fq *fq)
+{
+ u64 counter = atomic64_read(&iovad->fq_flush_finish_cnt);
+ unsigned idx;
+
+ assert_spin_locked(&fq->lock);
+
+ fq_ring_for_each(idx, fq) {
+
+ if (fq->entries[idx].counter >= counter)
+ break;
+
+ if (iovad->entry_dtor)
+ iovad->entry_dtor(fq->entries[idx].data);
+
+ free_iova_fast(iovad,
+ fq->entries[idx].iova_pfn,
+ fq->entries[idx].pages);
+
+ fq->head = (fq->head + 1) % IOVA_FQ_SIZE;
+ }
+}
+
+static void iova_domain_flush(struct iova_domain *iovad)
+{
+ atomic64_inc(&iovad->fq_flush_start_cnt);
+ iovad->flush_cb(iovad);
+ atomic64_inc(&iovad->fq_flush_finish_cnt);
+}
+
+static void fq_destroy_all_entries(struct iova_domain *iovad)
+{
+ int cpu;
+
+ /*
+ * This code runs when the iova_domain is being detroyed, so don't
+ * bother to free iovas, just call the entry_dtor on all remaining
+ * entries.
+ */
+ if (!iovad->entry_dtor)
+ return;
+
+ for_each_possible_cpu(cpu) {
+ struct iova_fq *fq = per_cpu_ptr(iovad->fq, cpu);
+ int idx;
+
+ fq_ring_for_each(idx, fq)
+ iovad->entry_dtor(fq->entries[idx].data);
+ }
+}
+
+static void fq_flush_timeout(unsigned long data)
+{
+ struct iova_domain *iovad = (struct iova_domain *)data;
+ int cpu;
+
+ atomic_set(&iovad->fq_timer_on, 0);
+ iova_domain_flush(iovad);
+
+ for_each_possible_cpu(cpu) {
+ unsigned long flags;
+ struct iova_fq *fq;
+
+ fq = per_cpu_ptr(iovad->fq, cpu);
+ spin_lock_irqsave(&fq->lock, flags);
+ fq_ring_free(iovad, fq);
+ spin_unlock_irqrestore(&fq->lock, flags);
+ }
+}
+
+void queue_iova(struct iova_domain *iovad,
+ unsigned long pfn, unsigned long pages,
+ unsigned long data)
+{
+ struct iova_fq *fq = get_cpu_ptr(iovad->fq);
+ unsigned long flags;
+ unsigned idx;
+
+ spin_lock_irqsave(&fq->lock, flags);
+
+ /*
+ * First remove all entries from the flush queue that have already been
+ * flushed out on another CPU. This makes the fq_full() check below less
+ * likely to be true.
+ */
+ fq_ring_free(iovad, fq);
+
+ if (fq_full(fq)) {
+ iova_domain_flush(iovad);
+ fq_ring_free(iovad, fq);
+ }
+
+ idx = fq_ring_add(fq);
+
+ fq->entries[idx].iova_pfn = pfn;
+ fq->entries[idx].pages = pages;
+ fq->entries[idx].data = data;
+ fq->entries[idx].counter = atomic64_read(&iovad->fq_flush_start_cnt);
+
+ spin_unlock_irqrestore(&fq->lock, flags);
+
+ if (atomic_cmpxchg(&iovad->fq_timer_on, 0, 1) == 0)
+ mod_timer(&iovad->fq_timer,
+ jiffies + msecs_to_jiffies(IOVA_FQ_TIMEOUT));
+
+ put_cpu_ptr(iovad->fq);
+}
+EXPORT_SYMBOL_GPL(queue_iova);
+
/**
* put_iova_domain - destroys the iova doamin
* @iovad: - iova domain in question.
@@ -433,6 +615,7 @@ void put_iova_domain(struct iova_domain *iovad)
struct rb_node *node;
unsigned long flags;
+ free_iova_flush_queue(iovad);
free_iova_rcaches(iovad);
spin_lock_irqsave(&iovad->iova_rbtree_lock, flags);
node = rb_first(&iovad->rbroot);