diff options
Diffstat (limited to 'drivers/dma')
| -rw-r--r-- | drivers/dma/dmaengine.c | 156 |
1 files changed, 147 insertions, 9 deletions
diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c index bbc89df6bc56..e721a1caff7f 100644 --- a/drivers/dma/dmaengine.c +++ b/drivers/dma/dmaengine.c @@ -65,6 +65,7 @@ #include <linux/acpi.h> #include <linux/acpi_dma.h> #include <linux/of_dma.h> +#include <linux/mempool.h> static DEFINE_MUTEX(dma_list_mutex); static DEFINE_IDR(dma_idr); @@ -901,6 +902,129 @@ void dma_async_device_unregister(struct dma_device *device) } EXPORT_SYMBOL(dma_async_device_unregister); +struct dmaengine_unmap_pool { + struct kmem_cache *cache; + const char *name; + mempool_t *pool; + size_t size; +}; + +#define __UNMAP_POOL(x) { .size = x, .name = "dmaengine-unmap-" __stringify(x) } +static struct dmaengine_unmap_pool unmap_pool[] = { + __UNMAP_POOL(2), + #if IS_ENABLED(CONFIG_ASYNC_TX_DMA) + __UNMAP_POOL(16), + __UNMAP_POOL(128), + __UNMAP_POOL(256), + #endif +}; + +static struct dmaengine_unmap_pool *__get_unmap_pool(int nr) +{ + int order = get_count_order(nr); + + switch (order) { + case 0 ... 1: + return &unmap_pool[0]; + case 2 ... 4: + return &unmap_pool[1]; + case 5 ... 7: + return &unmap_pool[2]; + case 8: + return &unmap_pool[3]; + default: + BUG(); + return NULL; + } +} + +static void dmaengine_unmap(struct kref *kref) +{ + struct dmaengine_unmap_data *unmap = container_of(kref, typeof(*unmap), kref); + struct device *dev = unmap->dev; + int cnt, i; + + cnt = unmap->to_cnt; + for (i = 0; i < cnt; i++) + dma_unmap_page(dev, unmap->addr[i], unmap->len, + DMA_TO_DEVICE); + cnt += unmap->from_cnt; + for (; i < cnt; i++) + dma_unmap_page(dev, unmap->addr[i], unmap->len, + DMA_FROM_DEVICE); + cnt += unmap->bidi_cnt; + for (; i < cnt; i++) + dma_unmap_page(dev, unmap->addr[i], unmap->len, + DMA_BIDIRECTIONAL); + mempool_free(unmap, __get_unmap_pool(cnt)->pool); +} + +void dmaengine_unmap_put(struct dmaengine_unmap_data *unmap) +{ + if (unmap) + kref_put(&unmap->kref, dmaengine_unmap); +} +EXPORT_SYMBOL_GPL(dmaengine_unmap_put); + +static void dmaengine_destroy_unmap_pool(void) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(unmap_pool); i++) { + struct dmaengine_unmap_pool *p = &unmap_pool[i]; + + if (p->pool) + mempool_destroy(p->pool); + p->pool = NULL; + if (p->cache) + kmem_cache_destroy(p->cache); + p->cache = NULL; + } +} + +static int __init dmaengine_init_unmap_pool(void) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(unmap_pool); i++) { + struct dmaengine_unmap_pool *p = &unmap_pool[i]; + size_t size; + + size = sizeof(struct dmaengine_unmap_data) + + sizeof(dma_addr_t) * p->size; + + p->cache = kmem_cache_create(p->name, size, 0, + SLAB_HWCACHE_ALIGN, NULL); + if (!p->cache) + break; + p->pool = mempool_create_slab_pool(1, p->cache); + if (!p->pool) + break; + } + + if (i == ARRAY_SIZE(unmap_pool)) + return 0; + + dmaengine_destroy_unmap_pool(); + return -ENOMEM; +} + +static struct dmaengine_unmap_data * +dmaengine_get_unmap_data(struct device *dev, int nr, gfp_t flags) +{ + struct dmaengine_unmap_data *unmap; + + unmap = mempool_alloc(__get_unmap_pool(nr)->pool, flags); + if (!unmap) + return NULL; + + memset(unmap, 0, sizeof(*unmap)); + kref_init(&unmap->kref); + unmap->dev = dev; + + return unmap; +} + /** * dma_async_memcpy_pg_to_pg - offloaded copy from page to page * @chan: DMA channel to offload copy to @@ -922,24 +1046,34 @@ dma_async_memcpy_pg_to_pg(struct dma_chan *chan, struct page *dest_pg, { struct dma_device *dev = chan->device; struct dma_async_tx_descriptor *tx; - dma_addr_t dma_dest, dma_src; + struct dmaengine_unmap_data *unmap; dma_cookie_t cookie; unsigned long flags; - dma_src = dma_map_page(dev->dev, src_pg, src_off, len, DMA_TO_DEVICE); - dma_dest = dma_map_page(dev->dev, dest_pg, dest_off, len, - DMA_FROM_DEVICE); - flags = DMA_CTRL_ACK; - tx = dev->device_prep_dma_memcpy(chan, dma_dest, dma_src, len, flags); + unmap = dmaengine_get_unmap_data(dev->dev, 2, GFP_NOIO); + if (!unmap) + return -ENOMEM; + + unmap->to_cnt = 1; + unmap->from_cnt = 1; + unmap->addr[0] = dma_map_page(dev->dev, src_pg, src_off, len, + DMA_TO_DEVICE); + unmap->addr[1] = dma_map_page(dev->dev, dest_pg, dest_off, len, + DMA_FROM_DEVICE); + unmap->len = len; + flags = DMA_CTRL_ACK | DMA_COMPL_SKIP_SRC_UNMAP | + DMA_COMPL_SKIP_DEST_UNMAP; + tx = dev->device_prep_dma_memcpy(chan, unmap->addr[1], unmap->addr[0], + len, flags); if (!tx) { - dma_unmap_page(dev->dev, dma_src, len, DMA_TO_DEVICE); - dma_unmap_page(dev->dev, dma_dest, len, DMA_FROM_DEVICE); + dmaengine_unmap_put(unmap); return -ENOMEM; } - tx->callback = NULL; + dma_set_unmap(tx, unmap); cookie = tx->tx_submit(tx); + dmaengine_unmap_put(unmap); preempt_disable(); __this_cpu_add(chan->local->bytes_transferred, len); @@ -1069,6 +1203,10 @@ EXPORT_SYMBOL_GPL(dma_run_dependencies); static int __init dma_bus_init(void) { + int err = dmaengine_init_unmap_pool(); + + if (err) + return err; return class_register(&dma_devclass); } arch_initcall(dma_bus_init); |