b43: Fix DMA for 30/32-bit DMA engines

This checks if the DMA address is bigger than what the controller can manage.
It will reallocate the buffers in the GFP_DMA zone in that case.

Signed-off-by: Michael Buesch <mb@bu3sch.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

2 files changed, 99 insertions, 58 deletions

diff --git a/drivers/net/wireless/b43/dma.c b/drivers/net/wireless/b43/dma.c
index 8a708b77925d..3dfb28a34be9 100644
--- a/drivers/net/wireless/b43/dma.c
+++ b/drivers/net/wireless/b43/dma.c
@@ -337,7 +337,7 @@ static inline int txring_to_priority(struct b43_dmaring *ring)
         return idx_to_prio[index];
 }
 
-u16 b43_dmacontroller_base(int dma64bit, int controller_idx)
+static u16 b43_dmacontroller_base(enum b43_dmatype type, int controller_idx)
 {
         static const u16 map64[] = {
                 B43_MMIO_DMA64_BASE0,
@@ -356,7 +356,7 @@ u16 b43_dmacontroller_base(int dma64bit, int controller_idx)
                 B43_MMIO_DMA32_BASE5,
         };
 
-        if (dma64bit) {
+        if (type == B43_DMA_64BIT) {
                 B43_WARN_ON(!(controller_idx >= 0 &&
                               controller_idx < ARRAY_SIZE(map64)));
                 return map64[controller_idx];
@@ -437,7 +437,7 @@ static int alloc_ringmemory(struct b43_dmaring *ring)
          * 02, which uses 64-bit DMA, needs the ring buffer in very low memory,
          * which accounts for the GFP_DMA flag below.
          */
-        if (ring->dma64)
+        if (ring->type == B43_DMA_64BIT)
                 flags |= GFP_DMA;
         ring->descbase = dma_alloc_coherent(dev, B43_DMA_RINGMEMSIZE,
                                             &(ring->dmabase), flags);
@@ -459,7 +459,8 @@ static void free_ringmemory(struct b43_dmaring *ring)
 }
 
 /* Reset the RX DMA channel */
-int b43_dmacontroller_rx_reset(struct b43_wldev *dev, u16 mmio_base, int dma64)
+static int b43_dmacontroller_rx_reset(struct b43_wldev *dev, u16 mmio_base,
+                                      enum b43_dmatype type)
 {
         int i;
         u32 value;
@@ -467,12 +468,13 @@ int b43_dmacontroller_rx_reset(struct b43_wldev *dev, u16 mmio_base, int dma64)
 
         might_sleep();
 
-        offset = dma64 ? B43_DMA64_RXCTL : B43_DMA32_RXCTL;
+        offset = (type == B43_DMA_64BIT) ? B43_DMA64_RXCTL : B43_DMA32_RXCTL;
         b43_write32(dev, mmio_base + offset, 0);
         for (i = 0; i < 10; i++) {
-                offset = dma64 ? B43_DMA64_RXSTATUS : B43_DMA32_RXSTATUS;
+                offset = (type == B43_DMA_64BIT) ? B43_DMA64_RXSTATUS :
+                                                   B43_DMA32_RXSTATUS;
                 value = b43_read32(dev, mmio_base + offset);
-                if (dma64) {
+                if (type == B43_DMA_64BIT) {
                         value &= B43_DMA64_RXSTAT;
                         if (value == B43_DMA64_RXSTAT_DISABLED) {
                                 i = -1;
@@ -496,7 +498,8 @@ int b43_dmacontroller_rx_reset(struct b43_wldev *dev, u16 mmio_base, int dma64)
 }
 
 /* Reset the TX DMA channel */
-int b43_dmacontroller_tx_reset(struct b43_wldev *dev, u16 mmio_base, int dma64)
+static int b43_dmacontroller_tx_reset(struct b43_wldev *dev, u16 mmio_base,
+                                      enum b43_dmatype type)
 {
         int i;
         u32 value;
@@ -505,9 +508,10 @@ int b43_dmacontroller_tx_reset(struct b43_wldev *dev, u16 mmio_base, int dma64)
         might_sleep();
 
         for (i = 0; i < 10; i++) {
-                offset = dma64 ? B43_DMA64_TXSTATUS : B43_DMA32_TXSTATUS;
+                offset = (type == B43_DMA_64BIT) ? B43_DMA64_TXSTATUS :
+                                                   B43_DMA32_TXSTATUS;
                 value = b43_read32(dev, mmio_base + offset);
-                if (dma64) {
+                if (type == B43_DMA_64BIT) {
                         value &= B43_DMA64_TXSTAT;
                         if (value == B43_DMA64_TXSTAT_DISABLED ||
                             value == B43_DMA64_TXSTAT_IDLEWAIT ||
@@ -522,12 +526,13 @@ int b43_dmacontroller_tx_reset(struct b43_wldev *dev, u16 mmio_base, int dma64)
                 }
                 msleep(1);
         }
-        offset = dma64 ? B43_DMA64_TXCTL : B43_DMA32_TXCTL;
+        offset = (type == B43_DMA_64BIT) ? B43_DMA64_TXCTL : B43_DMA32_TXCTL;
         b43_write32(dev, mmio_base + offset, 0);
         for (i = 0; i < 10; i++) {
-                offset = dma64 ? B43_DMA64_TXSTATUS : B43_DMA32_TXSTATUS;
+                offset = (type == B43_DMA_64BIT) ? B43_DMA64_TXSTATUS :
+                                                   B43_DMA32_TXSTATUS;
                 value = b43_read32(dev, mmio_base + offset);
-                if (dma64) {
+                if (type == B43_DMA_64BIT) {
                         value &= B43_DMA64_TXSTAT;
                         if (value == B43_DMA64_TXSTAT_DISABLED) {
                                 i = -1;
@@ -552,6 +557,33 @@ int b43_dmacontroller_tx_reset(struct b43_wldev *dev, u16 mmio_base, int dma64)
         return 0;
 }
 
+/* Check if a DMA mapping address is invalid. */
+static bool b43_dma_mapping_error(struct b43_dmaring *ring,
+                                  dma_addr_t addr,
+                                  size_t buffersize)
+{
+        if (unlikely(dma_mapping_error(addr)))
+                return 1;
+
+        switch (ring->type) {
+        case B43_DMA_30BIT:
+                if ((u64)addr + buffersize > (1ULL << 30))
+                        return 1;
+                break;
+        case B43_DMA_32BIT:
+                if ((u64)addr + buffersize > (1ULL << 32))
+                        return 1;
+                break;
+        case B43_DMA_64BIT:
+                /* Currently we can't have addresses beyond
+                 * 64bit in the kernel. */
+                break;
+        }
+
+        /* The address is OK. */
+        return 0;
+}
+
 static int setup_rx_descbuffer(struct b43_dmaring *ring,
                                struct b43_dmadesc_generic *desc,
                                struct b43_dmadesc_meta *meta, gfp_t gfp_flags)
@@ -567,7 +599,7 @@ static int setup_rx_descbuffer(struct b43_dmaring *ring,
         if (unlikely(!skb))
                 return -ENOMEM;
         dmaaddr = map_descbuffer(ring, skb->data, ring->rx_buffersize, 0);
-        if (dma_mapping_error(dmaaddr)) {
+        if (b43_dma_mapping_error(ring, dmaaddr, ring->rx_buffersize)) {
                 /* ugh. try to realloc in zone_dma */
                 gfp_flags |= GFP_DMA;
 
@@ -580,7 +612,7 @@ static int setup_rx_descbuffer(struct b43_dmaring *ring,
                                          ring->rx_buffersize, 0);
         }
 
-        if (dma_mapping_error(dmaaddr)) {
+        if (b43_dma_mapping_error(ring, dmaaddr, ring->rx_buffersize)) {
                 dev_kfree_skb_any(skb);
                 return -EIO;
         }
@@ -645,7 +677,7 @@ static int dmacontroller_setup(struct b43_dmaring *ring)
         u32 trans = ssb_dma_translation(ring->dev->dev);
 
         if (ring->tx) {
-                if (ring->dma64) {
+                if (ring->type == B43_DMA_64BIT) {
                         u64 ringbase = (u64) (ring->dmabase);
 
                         addrext = ((ringbase >> 32) & SSB_DMA_TRANSLATION_MASK)
@@ -677,7 +709,7 @@ static int dmacontroller_setup(struct b43_dmaring *ring)
                 err = alloc_initial_descbuffers(ring);
                 if (err)
                         goto out;
-                if (ring->dma64) {
+                if (ring->type == B43_DMA_64BIT) {
                         u64 ringbase = (u64) (ring->dmabase);
 
                         addrext = ((ringbase >> 32) & SSB_DMA_TRANSLATION_MASK)
@@ -722,16 +754,16 @@ static void dmacontroller_cleanup(struct b43_dmaring *ring)
 {
         if (ring->tx) {
                 b43_dmacontroller_tx_reset(ring->dev, ring->mmio_base,
-                                           ring->dma64);
-                if (ring->dma64) {
+                                           ring->type);
+                if (ring->type == B43_DMA_64BIT) {
                         b43_dma_write(ring, B43_DMA64_TXRINGLO, 0);
                         b43_dma_write(ring, B43_DMA64_TXRINGHI, 0);
                 } else
                         b43_dma_write(ring, B43_DMA32_TXRING, 0);
         } else {
                 b43_dmacontroller_rx_reset(ring->dev, ring->mmio_base,
-                                           ring->dma64);
-                if (ring->dma64) {
+                                           ring->type);
+                if (ring->type == B43_DMA_64BIT) {
                         b43_dma_write(ring, B43_DMA64_RXRINGLO, 0);
                         b43_dma_write(ring, B43_DMA64_RXRINGHI, 0);
                 } else
@@ -786,7 +818,8 @@ static u64 supported_dma_mask(struct b43_wldev *dev)
 static
 struct b43_dmaring *b43_setup_dmaring(struct b43_wldev *dev,
                                       int controller_index,
-                                      int for_tx, int dma64)
+                                      int for_tx,
+                                      enum b43_dmatype type)
 {
         struct b43_dmaring *ring;
         int err;
@@ -796,6 +829,7 @@ struct b43_dmaring *b43_setup_dmaring(struct b43_wldev *dev,
         ring = kzalloc(sizeof(*ring), GFP_KERNEL);
         if (!ring)
                 goto out;
+        ring->type = type;
 
         nr_slots = B43_RXRING_SLOTS;
         if (for_tx)
@@ -818,7 +852,7 @@ struct b43_dmaring *b43_setup_dmaring(struct b43_wldev *dev,
                                           b43_txhdr_size(dev),
                                           DMA_TO_DEVICE);
 
-                if (dma_mapping_error(dma_test)) {
+                if (b43_dma_mapping_error(ring, dma_test, b43_txhdr_size(dev))) {
                         /* ugh realloc */
                         kfree(ring->txhdr_cache);
                         ring->txhdr_cache = kcalloc(nr_slots,
@@ -832,7 +866,8 @@ struct b43_dmaring *b43_setup_dmaring(struct b43_wldev *dev,
                                                   b43_txhdr_size(dev),
                                                   DMA_TO_DEVICE);
 
-                        if (dma_mapping_error(dma_test))
+                        if (b43_dma_mapping_error(ring, dma_test,
+                                                  b43_txhdr_size(dev)))
                                 goto err_kfree_txhdr_cache;
                 }
 
@@ -843,10 +878,9 @@ struct b43_dmaring *b43_setup_dmaring(struct b43_wldev *dev,
 
         ring->dev = dev;
         ring->nr_slots = nr_slots;
-        ring->mmio_base = b43_dmacontroller_base(dma64, controller_index);
+        ring->mmio_base = b43_dmacontroller_base(type, controller_index);
         ring->index = controller_index;
-        ring->dma64 = !!dma64;
-        if (dma64)
+        if (type == B43_DMA_64BIT)
                 ring->ops = &dma64_ops;
         else
                 ring->ops = &dma32_ops;
@@ -896,8 +930,8 @@ static void b43_destroy_dmaring(struct b43_dmaring *ring)
         if (!ring)
                 return;
 
-        b43dbg(ring->dev->wl, "DMA-%s 0x%04X (%s) max used slots: %d/%d\n",
-               (ring->dma64) ? "64" : "32",
+        b43dbg(ring->dev->wl, "DMA-%u 0x%04X (%s) max used slots: %d/%d\n",
+               (unsigned int)(ring->type),
                ring->mmio_base,
                (ring->tx) ? "TX" : "RX", ring->max_used_slots, ring->nr_slots);
         /* Device IRQs are disabled prior entering this function,
@@ -941,12 +975,22 @@ int b43_dma_init(struct b43_wldev *dev)
         struct b43_dmaring *ring;
         int err;
         u64 dmamask;
-        int dma64 = 0;
+        enum b43_dmatype type;
 
         dmamask = supported_dma_mask(dev);
-        if (dmamask == DMA_64BIT_MASK)
-                dma64 = 1;
-
+        switch (dmamask) {
+        default:
+                B43_WARN_ON(1);
+        case DMA_30BIT_MASK:
+                type = B43_DMA_30BIT;
+                break;
+        case DMA_32BIT_MASK:
+                type = B43_DMA_32BIT;
+                break;
+        case DMA_64BIT_MASK:
+                type = B43_DMA_64BIT;
+                break;
+        }
         err = ssb_dma_set_mask(dev->dev, dmamask);
         if (err) {
                 b43err(dev->wl, "The machine/kernel does not support "
@@ -958,52 +1002,51 @@ int b43_dma_init(struct b43_wldev *dev)
 
         err = -ENOMEM;
         /* setup TX DMA channels. */
-        ring = b43_setup_dmaring(dev, 0, 1, dma64);
+        ring = b43_setup_dmaring(dev, 0, 1, type);
         if (!ring)
                 goto out;
         dma->tx_ring0 = ring;
 
-        ring = b43_setup_dmaring(dev, 1, 1, dma64);
+        ring = b43_setup_dmaring(dev, 1, 1, type);
         if (!ring)
                 goto err_destroy_tx0;
         dma->tx_ring1 = ring;
 
-        ring = b43_setup_dmaring(dev, 2, 1, dma64);
+        ring = b43_setup_dmaring(dev, 2, 1, type);
         if (!ring)
                 goto err_destroy_tx1;
         dma->tx_ring2 = ring;
 
-        ring = b43_setup_dmaring(dev, 3, 1, dma64);
+        ring = b43_setup_dmaring(dev, 3, 1, type);
         if (!ring)
                 goto err_destroy_tx2;
         dma->tx_ring3 = ring;
 
-        ring = b43_setup_dmaring(dev, 4, 1, dma64);
+        ring = b43_setup_dmaring(dev, 4, 1, type);
         if (!ring)
                 goto err_destroy_tx3;
         dma->tx_ring4 = ring;
 
-        ring = b43_setup_dmaring(dev, 5, 1, dma64);
+        ring = b43_setup_dmaring(dev, 5, 1, type);
         if (!ring)
                 goto err_destroy_tx4;
         dma->tx_ring5 = ring;
 
         /* setup RX DMA channels. */
-        ring = b43_setup_dmaring(dev, 0, 0, dma64);
+        ring = b43_setup_dmaring(dev, 0, 0, type);
         if (!ring)
                 goto err_destroy_tx5;
         dma->rx_ring0 = ring;
 
         if (dev->dev->id.revision < 5) {
-                ring = b43_setup_dmaring(dev, 3, 0, dma64);
+                ring = b43_setup_dmaring(dev, 3, 0, type);
                 if (!ring)
                         goto err_destroy_rx0;
                 dma->rx_ring3 = ring;
         }
 
-        b43dbg(dev->wl, "%d-bit DMA initialized\n",
-               (dmamask == DMA_64BIT_MASK) ? 64 :
-               (dmamask == DMA_32BIT_MASK) ? 32 : 30);
+        b43dbg(dev->wl, "%u-bit DMA initialized\n",
+               (unsigned int)type);
         err = 0;
       out:
         return err;
@@ -1146,7 +1189,7 @@ static int dma_tx_fragment(struct b43_dmaring *ring,
 
         meta_hdr->dmaaddr = map_descbuffer(ring, (unsigned char *)header,
                                            hdrsize, 1);
-        if (dma_mapping_error(meta_hdr->dmaaddr)) {
+        if (b43_dma_mapping_error(ring, meta_hdr->dmaaddr, hdrsize)) {
                 ring->current_slot = old_top_slot;
                 ring->used_slots = old_used_slots;
                 return -EIO;
@@ -1165,7 +1208,7 @@ static int dma_tx_fragment(struct b43_dmaring *ring,
 
         meta->dmaaddr = map_descbuffer(ring, skb->data, skb->len, 1);
         /* create a bounce buffer in zone_dma on mapping failure. */
-        if (dma_mapping_error(meta->dmaaddr)) {
+        if (b43_dma_mapping_error(ring, meta->dmaaddr, skb->len)) {
                 bounce_skb = __dev_alloc_skb(skb->len, GFP_ATOMIC | GFP_DMA);
                 if (!bounce_skb) {
                         ring->current_slot = old_top_slot;
@@ -1179,7 +1222,7 @@ static int dma_tx_fragment(struct b43_dmaring *ring,
                 skb = bounce_skb;
                 meta->skb = skb;
                 meta->dmaaddr = map_descbuffer(ring, skb->data, skb->len, 1);
-                if (dma_mapping_error(meta->dmaaddr)) {
+                if (b43_dma_mapping_error(ring, meta->dmaaddr, skb->len)) {
                         ring->current_slot = old_top_slot;
                         ring->used_slots = old_used_slots;
                         err = -EIO;
diff --git a/drivers/net/wireless/b43/dma.h b/drivers/net/wireless/b43/dma.h
index 58db03ac536e..c0d6b69e6501 100644
--- a/drivers/net/wireless/b43/dma.h
+++ b/drivers/net/wireless/b43/dma.h
@@ -203,6 +203,12 @@ struct b43_dma_ops {
         void (*set_current_rxslot) (struct b43_dmaring * ring, int slot);
 };
 
+enum b43_dmatype {
+        B43_DMA_30BIT   = 30,
+        B43_DMA_32BIT   = 32,
+        B43_DMA_64BIT   = 64,
+};
+
 struct b43_dmaring {
         /* Lowlevel DMA ops. */
         const struct b43_dma_ops *ops;
@@ -235,8 +241,8 @@ struct b43_dmaring {
         int index;
         /* Boolean. Is this a TX ring? */
         bool tx;
-        /* Boolean. 64bit DMA if true, 32bit DMA otherwise. */
-        bool dma64;
+        /* The type of DMA engine used. */
+        enum b43_dmatype type;
         /* Boolean. Is this ring stopped at ieee80211 level? */
         bool stopped;
         /* Lock, only used for TX. */
@@ -255,8 +261,7 @@ static inline u32 b43_dma_read(struct b43_dmaring *ring, u16 offset)
         return b43_read32(ring->dev, ring->mmio_base + offset);
 }
 
-static inline
-    void b43_dma_write(struct b43_dmaring *ring, u16 offset, u32 value)
+static inline void b43_dma_write(struct b43_dmaring *ring, u16 offset, u32 value)
 {
         b43_write32(ring->dev, ring->mmio_base + offset, value);
 }
@@ -264,13 +269,6 @@ static inline
 int b43_dma_init(struct b43_wldev *dev);
 void b43_dma_free(struct b43_wldev *dev);
 
-int b43_dmacontroller_rx_reset(struct b43_wldev *dev,
-                               u16 dmacontroller_mmio_base, int dma64);
-int b43_dmacontroller_tx_reset(struct b43_wldev *dev,
-                               u16 dmacontroller_mmio_base, int dma64);
-
-u16 b43_dmacontroller_base(int dma64bit, int dmacontroller_idx);
-
 void b43_dma_tx_suspend(struct b43_wldev *dev);
 void b43_dma_tx_resume(struct b43_wldev *dev);