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Diffstat (limited to 'drivers/iommu/dma-iommu.c')
-rw-r--r--drivers/iommu/dma-iommu.c200
1 files changed, 152 insertions, 48 deletions
diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c
index 4b1a88f514c9..85163a83df2f 100644
--- a/drivers/iommu/dma-iommu.c
+++ b/drivers/iommu/dma-iommu.c
@@ -43,14 +43,28 @@ enum iommu_dma_cookie_type {
IOMMU_DMA_MSI_COOKIE,
};
+enum iommu_dma_queue_type {
+ IOMMU_DMA_OPTS_PER_CPU_QUEUE,
+ IOMMU_DMA_OPTS_SINGLE_QUEUE,
+};
+
+struct iommu_dma_options {
+ enum iommu_dma_queue_type qt;
+ size_t fq_size;
+ unsigned int fq_timeout;
+};
+
struct iommu_dma_cookie {
enum iommu_dma_cookie_type type;
union {
/* Full allocator for IOMMU_DMA_IOVA_COOKIE */
struct {
struct iova_domain iovad;
-
- struct iova_fq __percpu *fq; /* Flush queue */
+ /* Flush queue */
+ union {
+ struct iova_fq *single_fq;
+ struct iova_fq __percpu *percpu_fq;
+ };
/* Number of TLB flushes that have been started */
atomic64_t fq_flush_start_cnt;
/* Number of TLB flushes that have been finished */
@@ -67,6 +81,8 @@ struct iommu_dma_cookie {
/* Domain for flush queue callback; NULL if flush queue not in use */
struct iommu_domain *fq_domain;
+ /* Options for dma-iommu use */
+ struct iommu_dma_options options;
struct mutex mutex;
};
@@ -84,10 +100,12 @@ static int __init iommu_dma_forcedac_setup(char *str)
early_param("iommu.forcedac", iommu_dma_forcedac_setup);
/* Number of entries per flush queue */
-#define IOVA_FQ_SIZE 256
+#define IOVA_DEFAULT_FQ_SIZE 256
+#define IOVA_SINGLE_FQ_SIZE 32768
/* Timeout (in ms) after which entries are flushed from the queue */
-#define IOVA_FQ_TIMEOUT 10
+#define IOVA_DEFAULT_FQ_TIMEOUT 10
+#define IOVA_SINGLE_FQ_TIMEOUT 1000
/* Flush queue entry for deferred flushing */
struct iova_fq_entry {
@@ -99,18 +117,19 @@ struct iova_fq_entry {
/* Per-CPU flush queue structure */
struct iova_fq {
- struct iova_fq_entry entries[IOVA_FQ_SIZE];
- unsigned int head, tail;
spinlock_t lock;
+ unsigned int head, tail;
+ unsigned int mod_mask;
+ struct iova_fq_entry entries[];
};
#define fq_ring_for_each(i, fq) \
- for ((i) = (fq)->head; (i) != (fq)->tail; (i) = ((i) + 1) % IOVA_FQ_SIZE)
+ for ((i) = (fq)->head; (i) != (fq)->tail; (i) = ((i) + 1) & (fq)->mod_mask)
static inline bool fq_full(struct iova_fq *fq)
{
assert_spin_locked(&fq->lock);
- return (((fq->tail + 1) % IOVA_FQ_SIZE) == fq->head);
+ return (((fq->tail + 1) & fq->mod_mask) == fq->head);
}
static inline unsigned int fq_ring_add(struct iova_fq *fq)
@@ -119,12 +138,12 @@ static inline unsigned int fq_ring_add(struct iova_fq *fq)
assert_spin_locked(&fq->lock);
- fq->tail = (idx + 1) % IOVA_FQ_SIZE;
+ fq->tail = (idx + 1) & fq->mod_mask;
return idx;
}
-static void fq_ring_free(struct iommu_dma_cookie *cookie, struct iova_fq *fq)
+static void fq_ring_free_locked(struct iommu_dma_cookie *cookie, struct iova_fq *fq)
{
u64 counter = atomic64_read(&cookie->fq_flush_finish_cnt);
unsigned int idx;
@@ -141,10 +160,19 @@ static void fq_ring_free(struct iommu_dma_cookie *cookie, struct iova_fq *fq)
fq->entries[idx].iova_pfn,
fq->entries[idx].pages);
- fq->head = (fq->head + 1) % IOVA_FQ_SIZE;
+ fq->head = (fq->head + 1) & fq->mod_mask;
}
}
+static void fq_ring_free(struct iommu_dma_cookie *cookie, struct iova_fq *fq)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&fq->lock, flags);
+ fq_ring_free_locked(cookie, fq);
+ spin_unlock_irqrestore(&fq->lock, flags);
+}
+
static void fq_flush_iotlb(struct iommu_dma_cookie *cookie)
{
atomic64_inc(&cookie->fq_flush_start_cnt);
@@ -160,14 +188,11 @@ static void fq_flush_timeout(struct timer_list *t)
atomic_set(&cookie->fq_timer_on, 0);
fq_flush_iotlb(cookie);
- for_each_possible_cpu(cpu) {
- unsigned long flags;
- struct iova_fq *fq;
-
- fq = per_cpu_ptr(cookie->fq, cpu);
- spin_lock_irqsave(&fq->lock, flags);
- fq_ring_free(cookie, fq);
- spin_unlock_irqrestore(&fq->lock, flags);
+ if (cookie->options.qt == IOMMU_DMA_OPTS_SINGLE_QUEUE) {
+ fq_ring_free(cookie, cookie->single_fq);
+ } else {
+ for_each_possible_cpu(cpu)
+ fq_ring_free(cookie, per_cpu_ptr(cookie->percpu_fq, cpu));
}
}
@@ -188,7 +213,11 @@ static void queue_iova(struct iommu_dma_cookie *cookie,
*/
smp_mb();
- fq = raw_cpu_ptr(cookie->fq);
+ if (cookie->options.qt == IOMMU_DMA_OPTS_SINGLE_QUEUE)
+ fq = cookie->single_fq;
+ else
+ fq = raw_cpu_ptr(cookie->percpu_fq);
+
spin_lock_irqsave(&fq->lock, flags);
/*
@@ -196,11 +225,11 @@ static void queue_iova(struct iommu_dma_cookie *cookie,
* flushed out on another CPU. This makes the fq_full() check below less
* likely to be true.
*/
- fq_ring_free(cookie, fq);
+ fq_ring_free_locked(cookie, fq);
if (fq_full(fq)) {
fq_flush_iotlb(cookie);
- fq_ring_free(cookie, fq);
+ fq_ring_free_locked(cookie, fq);
}
idx = fq_ring_add(fq);
@@ -216,34 +245,95 @@ static void queue_iova(struct iommu_dma_cookie *cookie,
if (!atomic_read(&cookie->fq_timer_on) &&
!atomic_xchg(&cookie->fq_timer_on, 1))
mod_timer(&cookie->fq_timer,
- jiffies + msecs_to_jiffies(IOVA_FQ_TIMEOUT));
+ jiffies + msecs_to_jiffies(cookie->options.fq_timeout));
}
-static void iommu_dma_free_fq(struct iommu_dma_cookie *cookie)
+static void iommu_dma_free_fq_single(struct iova_fq *fq)
{
- int cpu, idx;
+ int idx;
- if (!cookie->fq)
- return;
+ fq_ring_for_each(idx, fq)
+ put_pages_list(&fq->entries[idx].freelist);
+ vfree(fq);
+}
+
+static void iommu_dma_free_fq_percpu(struct iova_fq __percpu *percpu_fq)
+{
+ int cpu, idx;
- del_timer_sync(&cookie->fq_timer);
/* The IOVAs will be torn down separately, so just free our queued pages */
for_each_possible_cpu(cpu) {
- struct iova_fq *fq = per_cpu_ptr(cookie->fq, cpu);
+ struct iova_fq *fq = per_cpu_ptr(percpu_fq, cpu);
fq_ring_for_each(idx, fq)
put_pages_list(&fq->entries[idx].freelist);
}
- free_percpu(cookie->fq);
+ free_percpu(percpu_fq);
+}
+
+static void iommu_dma_free_fq(struct iommu_dma_cookie *cookie)
+{
+ if (!cookie->fq_domain)
+ return;
+
+ del_timer_sync(&cookie->fq_timer);
+ if (cookie->options.qt == IOMMU_DMA_OPTS_SINGLE_QUEUE)
+ iommu_dma_free_fq_single(cookie->single_fq);
+ else
+ iommu_dma_free_fq_percpu(cookie->percpu_fq);
+}
+
+static void iommu_dma_init_one_fq(struct iova_fq *fq, size_t fq_size)
+{
+ int i;
+
+ fq->head = 0;
+ fq->tail = 0;
+ fq->mod_mask = fq_size - 1;
+
+ spin_lock_init(&fq->lock);
+
+ for (i = 0; i < fq_size; i++)
+ INIT_LIST_HEAD(&fq->entries[i].freelist);
+}
+
+static int iommu_dma_init_fq_single(struct iommu_dma_cookie *cookie)
+{
+ size_t fq_size = cookie->options.fq_size;
+ struct iova_fq *queue;
+
+ queue = vmalloc(struct_size(queue, entries, fq_size));
+ if (!queue)
+ return -ENOMEM;
+ iommu_dma_init_one_fq(queue, fq_size);
+ cookie->single_fq = queue;
+
+ return 0;
+}
+
+static int iommu_dma_init_fq_percpu(struct iommu_dma_cookie *cookie)
+{
+ size_t fq_size = cookie->options.fq_size;
+ struct iova_fq __percpu *queue;
+ int cpu;
+
+ queue = __alloc_percpu(struct_size(queue, entries, fq_size),
+ __alignof__(*queue));
+ if (!queue)
+ return -ENOMEM;
+
+ for_each_possible_cpu(cpu)
+ iommu_dma_init_one_fq(per_cpu_ptr(queue, cpu), fq_size);
+ cookie->percpu_fq = queue;
+ return 0;
}
/* sysfs updates are serialised by the mutex of the group owning @domain */
int iommu_dma_init_fq(struct iommu_domain *domain)
{
struct iommu_dma_cookie *cookie = domain->iova_cookie;
- struct iova_fq __percpu *queue;
- int i, cpu;
+ int rc;
if (cookie->fq_domain)
return 0;
@@ -251,26 +341,16 @@ int iommu_dma_init_fq(struct iommu_domain *domain)
atomic64_set(&cookie->fq_flush_start_cnt, 0);
atomic64_set(&cookie->fq_flush_finish_cnt, 0);
- queue = alloc_percpu(struct iova_fq);
- if (!queue) {
+ if (cookie->options.qt == IOMMU_DMA_OPTS_SINGLE_QUEUE)
+ rc = iommu_dma_init_fq_single(cookie);
+ else
+ rc = iommu_dma_init_fq_percpu(cookie);
+
+ if (rc) {
pr_warn("iova flush queue initialization failed\n");
return -ENOMEM;
}
- for_each_possible_cpu(cpu) {
- struct iova_fq *fq = per_cpu_ptr(queue, cpu);
-
- fq->head = 0;
- fq->tail = 0;
-
- spin_lock_init(&fq->lock);
-
- for (i = 0; i < IOVA_FQ_SIZE; i++)
- INIT_LIST_HEAD(&fq->entries[i].freelist);
- }
-
- cookie->fq = queue;
-
timer_setup(&cookie->fq_timer, fq_flush_timeout, 0);
atomic_set(&cookie->fq_timer_on, 0);
/*
@@ -555,6 +635,28 @@ static bool dev_use_sg_swiotlb(struct device *dev, struct scatterlist *sg,
}
/**
+ * iommu_dma_init_options - Initialize dma-iommu options
+ * @options: The options to be initialized
+ * @dev: Device the options are set for
+ *
+ * This allows tuning dma-iommu specific to device properties
+ */
+static void iommu_dma_init_options(struct iommu_dma_options *options,
+ struct device *dev)
+{
+ /* Shadowing IOTLB flushes do better with a single large queue */
+ if (dev->iommu->shadow_on_flush) {
+ options->qt = IOMMU_DMA_OPTS_SINGLE_QUEUE;
+ options->fq_timeout = IOVA_SINGLE_FQ_TIMEOUT;
+ options->fq_size = IOVA_SINGLE_FQ_SIZE;
+ } else {
+ options->qt = IOMMU_DMA_OPTS_PER_CPU_QUEUE;
+ options->fq_size = IOVA_DEFAULT_FQ_SIZE;
+ options->fq_timeout = IOVA_DEFAULT_FQ_TIMEOUT;
+ }
+}
+
+/**
* iommu_dma_init_domain - Initialise a DMA mapping domain
* @domain: IOMMU domain previously prepared by iommu_get_dma_cookie()
* @base: IOVA at which the mappable address space starts
@@ -614,6 +716,8 @@ static int iommu_dma_init_domain(struct iommu_domain *domain, dma_addr_t base,
if (ret)
goto done_unlock;
+ iommu_dma_init_options(&cookie->options, dev);
+
/* If the FQ fails we can simply fall back to strict mode */
if (domain->type == IOMMU_DOMAIN_DMA_FQ &&
(!device_iommu_capable(dev, IOMMU_CAP_DEFERRED_FLUSH) || iommu_dma_init_fq(domain)))