From: Joerg Roedel <jroe...@suse.de>
Add a timer to flush entries from the Flush-Queues every
10ms. This makes sure that no stale TLB entries remain for
too long after an IOVA has been unmapped.
Signed-off-by: Joerg Roedel <jroe...@suse.de>
---
drivers/iommu/iova.c | 32 ++++++++++++++++++++++++++++++++
include/linux/iova.h | 8 ++++++++
2 files changed, 40 insertions(+)
diff --git a/drivers/iommu/iova.c b/drivers/iommu/iova.c
index 749d395..33edfa7 100644
--- a/drivers/iommu/iova.c
+++ b/drivers/iommu/iova.c
@@ -33,6 +33,7 @@ static unsigned long iova_rcache_get(struct iova_domain
*iovad,
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,
@@ -62,7 +63,11 @@ 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;
@@ -95,6 +100,9 @@ int init_iova_flush_queue(struct iova_domain *iovad,
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);
@@ -539,6 +547,25 @@ static void fq_destroy_all_entries(struct iova_domain
*iovad)
}
}
+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)
@@ -569,6 +596,11 @@ void queue_iova(struct iova_domain *iovad,
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);
diff --git a/include/linux/iova.h b/include/linux/iova.h
index 913a690..d179b9b 100644
--- a/include/linux/iova.h
+++ b/include/linux/iova.h
@@ -48,6 +48,9 @@ typedef void (* iova_entry_dtor)(unsigned long data);
/* Number of entries per Flush Queue */
#define IOVA_FQ_SIZE 256
+/* Timeout (in ms) after which entries are flushed from the Flush-Queue */
+#define IOVA_FQ_TIMEOUT 10
+
/* Flush Queue entry for defered flushing */
struct iova_fq_entry {
unsigned long iova_pfn;
@@ -86,6 +89,11 @@ struct iova_domain {
atomic64_t fq_flush_finish_cnt; /* Number of TLB flushes that
have been finished */
+
+ struct timer_list fq_timer; /* Timer to regularily empty the
+ flush-queues */
+ atomic_t fq_timer_on; /* 1 when timer is active, 0
+ when not */
};
static inline unsigned long iova_size(struct iova *iova)
--
2.7.4
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