[ARM] Clean up dmabounce

Encapsulate pool data into dmabounce_pool.  Only account successful
allocations.  Use dma_mapping_error().

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 86 insertions, 79 deletions

diff --git a/arch/arm/common/dmabounce.c b/arch/arm/common/dmabounce.c
index cbf2165476b0..ad6c89a555bb 100644
--- a/arch/arm/common/dmabounce.c
+++ b/arch/arm/common/dmabounce.c
@@ -33,8 +33,8 @@
 #include <asm/cacheflush.h>
 
 #undef DEBUG
-
 #undef STATS
+
 #ifdef STATS
 #define DO_STATS(X) do { X ; } while (0)
 #else
@@ -52,26 +52,31 @@ struct safe_buffer {
         int             direction;
 
         /* safe buffer info */
-        struct dma_pool *pool;
+        struct dmabounce_pool *pool;
         void            *safe;
         dma_addr_t      safe_dma_addr;
 };
 
+struct dmabounce_pool {
+        unsigned long   size;
+        struct dma_pool *pool;
+#ifdef STATS
+        unsigned long   allocs;
+#endif
+};
+
 struct dmabounce_device_info {
         struct list_head node;
 
         struct device *dev;
-        struct dma_pool *small_buffer_pool;
-        struct dma_pool *large_buffer_pool;
         struct list_head safe_buffers;
-        unsigned long small_buffer_size, large_buffer_size;
 #ifdef STATS
-        unsigned long sbp_allocs;
-        unsigned long lbp_allocs;
         unsigned long total_allocs;
         unsigned long map_op_count;
         unsigned long bounce_count;
 #endif
+        struct dmabounce_pool   small;
+        struct dmabounce_pool   large;
 };
 
 static LIST_HEAD(dmabounce_devs);
@@ -82,9 +87,9 @@ static void print_alloc_stats(struct dmabounce_device_info *device_info)
         printk(KERN_INFO
                 "%s: dmabounce: sbp: %lu, lbp: %lu, other: %lu, total: %lu\n",
                 device_info->dev->bus_id,
-                device_info->sbp_allocs, device_info->lbp_allocs,
-                device_info->total_allocs - device_info->sbp_allocs -
-                        device_info->lbp_allocs,
+                device_info->small.allocs, device_info->large.allocs,
+                device_info->total_allocs - device_info->small.allocs -
+                        device_info->large.allocs,
                 device_info->total_allocs);
 }
 #endif
@@ -106,18 +111,22 @@ find_dmabounce_dev(struct device *dev)
 /* allocate a 'safe' buffer and keep track of it */
 static inline struct safe_buffer *
 alloc_safe_buffer(struct dmabounce_device_info *device_info, void *ptr,
-                        size_t size, enum dma_data_direction dir)
+                  size_t size, enum dma_data_direction dir)
 {
         struct safe_buffer *buf;
-        struct dma_pool *pool;
+        struct dmabounce_pool *pool;
         struct device *dev = device_info->dev;
-        void *safe;
-        dma_addr_t safe_dma_addr;
 
         dev_dbg(dev, "%s(ptr=%p, size=%d, dir=%d)\n",
                 __func__, ptr, size, dir);
 
-        DO_STATS ( device_info->total_allocs++ );
+        if (size <= device_info->small.size) {
+                pool = &device_info->small;
+        } else if (size <= device_info->large.size) {
+                pool = &device_info->large;
+        } else {
+                pool = NULL;
+        }
 
         buf = kmalloc(sizeof(struct safe_buffer), GFP_ATOMIC);
         if (buf == NULL) {
@@ -125,41 +134,35 @@ alloc_safe_buffer(struct dmabounce_device_info *device_info, void *ptr,
                 return NULL;
         }
 
-        if (size <= device_info->small_buffer_size) {
-                pool = device_info->small_buffer_pool;
-                safe = dma_pool_alloc(pool, GFP_ATOMIC, &safe_dma_addr);
-
-                DO_STATS ( device_info->sbp_allocs++ );
-        } else if (size <= device_info->large_buffer_size) {
-                pool = device_info->large_buffer_pool;
-                safe = dma_pool_alloc(pool, GFP_ATOMIC, &safe_dma_addr);
+        buf->ptr = ptr;
+        buf->size = size;
+        buf->direction = dir;
+        buf->pool = pool;
 
-                DO_STATS ( device_info->lbp_allocs++ );
+        if (pool) {
+                buf->safe = dma_pool_alloc(pool->pool, GFP_ATOMIC,
+                                           &buf->safe_dma_addr);
         } else {
-                pool = NULL;
-                safe = dma_alloc_coherent(dev, size, &safe_dma_addr, GFP_ATOMIC);
+                buf->safe = dma_alloc_coherent(dev, size, &buf->safe_dma_addr,
+                                               GFP_ATOMIC);
         }
 
-        if (safe == NULL) {
-                dev_warn(device_info->dev,
-                        "%s: could not alloc dma memory (size=%d)\n",
-                       __func__, size);
+        if (buf->safe == NULL) {
+                dev_warn(dev,
+                         "%s: could not alloc dma memory (size=%d)\n",
+                         __func__, size);
                 kfree(buf);
                 return NULL;
         }
 
 #ifdef STATS
+        if (pool)
+                pool->allocs++;
+        device_info->total_allocs++;
         if (device_info->total_allocs % 1000 == 0)
                 print_alloc_stats(device_info);
 #endif
 
-        buf->ptr = ptr;
-        buf->size = size;
-        buf->direction = dir;
-        buf->pool = pool;
-        buf->safe = safe;
-        buf->safe_dma_addr = safe_dma_addr;
-
         list_add(&buf->node, &device_info->safe_buffers);
 
         return buf;
@@ -186,7 +189,7 @@ free_safe_buffer(struct dmabounce_device_info *device_info, struct safe_buffer *
         list_del(&buf->node);
 
         if (buf->pool)
-                dma_pool_free(buf->pool, buf->safe, buf->safe_dma_addr);
+                dma_pool_free(buf->pool->pool, buf->safe, buf->safe_dma_addr);
         else
                 dma_free_coherent(device_info->dev, buf->size, buf->safe,
                                     buf->safe_dma_addr);
@@ -197,12 +200,10 @@ free_safe_buffer(struct dmabounce_device_info *device_info, struct safe_buffer *
 /* ************************************************** */
 
 #ifdef STATS
-
 static void print_map_stats(struct dmabounce_device_info *device_info)
 {
-        printk(KERN_INFO
-                "%s: dmabounce: map_op_count=%lu, bounce_count=%lu\n",
-                device_info->dev->bus_id,
+        dev_info(device_info->dev,
+                "dmabounce: map_op_count=%lu, bounce_count=%lu\n",
                 device_info->map_op_count, device_info->bounce_count);
 }
 #endif
@@ -258,13 +259,13 @@ map_single(struct device *dev, void *ptr, size_t size,
                                 __func__, ptr, buf->safe, size);
                         memcpy(buf->safe, ptr, size);
                 }
-                consistent_sync(buf->safe, size, dir);
+                ptr = buf->safe;
 
                 dma_addr = buf->safe_dma_addr;
-        } else {
-                consistent_sync(ptr, size, dir);
         }
 
+        consistent_sync(ptr, size, dir);
+
         return dma_addr;
 }
 
@@ -278,7 +279,7 @@ unmap_single(struct device *dev, dma_addr_t dma_addr, size_t size,
         /*
          * Trying to unmap an invalid mapping
          */
-        if (dma_addr == ~0) {
+        if (dma_mapping_error(dma_addr)) {
                 dev_err(dev, "Trying to unmap invalid mapping\n");
                 return;
         }
@@ -570,11 +571,25 @@ dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg, int nents,
         local_irq_restore(flags);
 }
 
+static int
+dmabounce_init_pool(struct dmabounce_pool *pool, struct device *dev, const char *name,
+                    unsigned long size)
+{
+        pool->size = size;
+        DO_STATS(pool->allocs = 0);
+        pool->pool = dma_pool_create(name, dev, size,
+                                     0 /* byte alignment */,
+                                     0 /* no page-crossing issues */);
+
+        return pool->pool ? 0 : -ENOMEM;
+}
+
 int
 dmabounce_register_dev(struct device *dev, unsigned long small_buffer_size,
                         unsigned long large_buffer_size)
 {
         struct dmabounce_device_info *device_info;
+        int ret;
 
         device_info = kmalloc(sizeof(struct dmabounce_device_info), GFP_ATOMIC);
         if (!device_info) {
@@ -584,45 +599,31 @@ dmabounce_register_dev(struct device *dev, unsigned long small_buffer_size,
                 return -ENOMEM;
         }
 
-        device_info->small_buffer_pool =
-                dma_pool_create("small_dmabounce_pool",
-                                dev,
-                                small_buffer_size,
-                                0 /* byte alignment */,
-                                0 /* no page-crossing issues */);
-        if (!device_info->small_buffer_pool) {
-                printk(KERN_ERR
-                        "dmabounce: could not allocate small DMA pool for %s\n",
-                        dev->bus_id);
-                kfree(device_info);
-                return -ENOMEM;
+        ret = dmabounce_init_pool(&device_info->small, dev,
+                                  "small_dmabounce_pool", small_buffer_size);
+        if (ret) {
+                dev_err(dev,
+                        "dmabounce: could not allocate DMA pool for %ld byte objects\n",
+                        small_buffer_size);
+                goto err_free;
         }
 
         if (large_buffer_size) {
-                device_info->large_buffer_pool =
-                        dma_pool_create("large_dmabounce_pool",
-                                        dev,
-                                        large_buffer_size,
-                                        0 /* byte alignment */,
-                                        0 /* no page-crossing issues */);
-                if (!device_info->large_buffer_pool) {
-                printk(KERN_ERR
-                        "dmabounce: could not allocate large DMA pool for %s\n",
-                        dev->bus_id);
-                        dma_pool_destroy(device_info->small_buffer_pool);
-
-                        return -ENOMEM;
+                ret = dmabounce_init_pool(&device_info->large, dev,
+                                          "large_dmabounce_pool",
+                                          large_buffer_size);
+                if (ret) {
+                        dev_err(dev,
+                                "dmabounce: could not allocate DMA pool for %ld byte objects\n",
+                                large_buffer_size);
+                        goto err_destroy;
                 }
         }
 
         device_info->dev = dev;
-        device_info->small_buffer_size = small_buffer_size;
-        device_info->large_buffer_size = large_buffer_size;
         INIT_LIST_HEAD(&device_info->safe_buffers);
 
 #ifdef STATS
-        device_info->sbp_allocs = 0;
-        device_info->lbp_allocs = 0;
         device_info->total_allocs = 0;
         device_info->map_op_count = 0;
         device_info->bounce_count = 0;
@@ -634,6 +635,12 @@ dmabounce_register_dev(struct device *dev, unsigned long small_buffer_size,
                 dev->bus_id, dev->bus->name);
 
         return 0;
+
+ err_destroy:
+        dma_pool_destroy(device_info->small.pool);
+ err_free:
+        kfree(device_info);
+        return ret;
 }
 
 void
@@ -655,10 +662,10 @@ dmabounce_unregister_dev(struct device *dev)
                 BUG();
         }
 
-        if (device_info->small_buffer_pool)
-                dma_pool_destroy(device_info->small_buffer_pool);
-        if (device_info->large_buffer_pool)
-                dma_pool_destroy(device_info->large_buffer_pool);
+        if (device_info->small.pool)
+                dma_pool_destroy(device_info->small.pool);
+        if (device_info->large.pool)
+                dma_pool_destroy(device_info->large.pool);
 
 #ifdef STATS
         print_alloc_stats(device_info);