9 files changed, 30 insertions, 52 deletions

diff --git a/drivers/firewire/core-card.c b/drivers/firewire/core-card.c
index 3c44fbc81acb..e119f1e6ba47 100644
--- a/drivers/firewire/core-card.c
+++ b/drivers/firewire/core-card.c
@@ -258,8 +258,7 @@ static void allocate_broadcast_channel(struct fw_card *card, int generation)
 
         if (!card->broadcast_channel_allocated) {
                 fw_iso_resource_manage(card, generation, 1ULL << 31,
-                                       &channel, &bandwidth, true,
-                                       card->bm_transaction_data);
+                                       &channel, &bandwidth, true);
                 if (channel != 31) {
                         fw_notify("failed to allocate broadcast channel\n");
                         return;
@@ -294,6 +293,7 @@ static void bm_work(struct work_struct *work)
         bool root_device_is_cmc;
         bool irm_is_1394_1995_only;
         bool keep_this_irm;
+        __be32 transaction_data[2];
 
         spin_lock_irq(&card->lock);
 
@@ -355,21 +355,21 @@ static void bm_work(struct work_struct *work)
                         goto pick_me;
                 }
 
-                card->bm_transaction_data[0] = cpu_to_be32(0x3f);
-                card->bm_transaction_data[1] = cpu_to_be32(local_id);
+                transaction_data[0] = cpu_to_be32(0x3f);
+                transaction_data[1] = cpu_to_be32(local_id);
 
                 spin_unlock_irq(&card->lock);
 
                 rcode = fw_run_transaction(card, TCODE_LOCK_COMPARE_SWAP,
                                 irm_id, generation, SCODE_100,
                                 CSR_REGISTER_BASE + CSR_BUS_MANAGER_ID,
-                                card->bm_transaction_data, 8);
+                                transaction_data, 8);
 
                 if (rcode == RCODE_GENERATION)
                         /* Another bus reset, BM work has been rescheduled. */
                         goto out;
 
-                bm_id = be32_to_cpu(card->bm_transaction_data[0]);
+                bm_id = be32_to_cpu(transaction_data[0]);
 
                 spin_lock_irq(&card->lock);
                 if (rcode == RCODE_COMPLETE && generation == card->generation)
@@ -490,11 +490,11 @@ static void bm_work(struct work_struct *work)
                 /*
                  * Make sure that the cycle master sends cycle start packets.
                  */
-                card->bm_transaction_data[0] = cpu_to_be32(CSR_STATE_BIT_CMSTR);
+                transaction_data[0] = cpu_to_be32(CSR_STATE_BIT_CMSTR);
                 rcode = fw_run_transaction(card, TCODE_WRITE_QUADLET_REQUEST,
                                 root_id, generation, SCODE_100,
                                 CSR_REGISTER_BASE + CSR_STATE_SET,
-                                card->bm_transaction_data, 4);
+                                transaction_data, 4);
                 if (rcode == RCODE_GENERATION)
                         goto out;
         }
diff --git a/drivers/firewire/core-cdev.c b/drivers/firewire/core-cdev.c
index 62ac111af243..2a3f1c4d6906 100644
--- a/drivers/firewire/core-cdev.c
+++ b/drivers/firewire/core-cdev.c
@@ -141,7 +141,6 @@ struct iso_resource {
         int generation;
         u64 channels;
         s32 bandwidth;
-        __be32 transaction_data[2];
         struct iso_resource_event *e_alloc, *e_dealloc;
 };
 
@@ -1229,8 +1228,7 @@ static void iso_resource_work(struct work_struct *work)
                         r->channels, &channel, &bandwidth,
                         todo == ISO_RES_ALLOC ||
                         todo == ISO_RES_REALLOC ||
-                        todo == ISO_RES_ALLOC_ONCE,
-                        r->transaction_data);
+                        todo == ISO_RES_ALLOC_ONCE);
         /*
          * Is this generation outdated already?  As long as this resource sticks
          * in the idr, it will be scheduled again for a newer generation or at
diff --git a/drivers/firewire/core-iso.c b/drivers/firewire/core-iso.c
index 481056df9268..f872ede5af37 100644
--- a/drivers/firewire/core-iso.c
+++ b/drivers/firewire/core-iso.c
@@ -196,9 +196,10 @@ EXPORT_SYMBOL(fw_iso_context_stop);
  */
 
 static int manage_bandwidth(struct fw_card *card, int irm_id, int generation,
-                            int bandwidth, bool allocate, __be32 data[2])
+                            int bandwidth, bool allocate)
 {
         int try, new, old = allocate ? BANDWIDTH_AVAILABLE_INITIAL : 0;
+        __be32 data[2];
 
         /*
          * On a 1394a IRM with low contention, try < 1 is enough.
@@ -233,9 +234,10 @@ static int manage_bandwidth(struct fw_card *card, int irm_id, int generation,
 }
 
 static int manage_channel(struct fw_card *card, int irm_id, int generation,
-                u32 channels_mask, u64 offset, bool allocate, __be32 data[2])
+                u32 channels_mask, u64 offset, bool allocate)
 {
         __be32 bit, all, old;
+        __be32 data[2];
         int channel, ret = -EIO, retry = 5;
 
         old = all = allocate ? cpu_to_be32(~0) : 0;
@@ -284,7 +286,7 @@ static int manage_channel(struct fw_card *card, int irm_id, int generation,
 }
 
 static void deallocate_channel(struct fw_card *card, int irm_id,
-                               int generation, int channel, __be32 buffer[2])
+                               int generation, int channel)
 {
         u32 mask;
         u64 offset;
@@ -293,7 +295,7 @@ static void deallocate_channel(struct fw_card *card, int irm_id,
         offset = channel < 32 ? CSR_REGISTER_BASE + CSR_CHANNELS_AVAILABLE_HI :
                                 CSR_REGISTER_BASE + CSR_CHANNELS_AVAILABLE_LO;
 
-        manage_channel(card, irm_id, generation, mask, offset, false, buffer);
+        manage_channel(card, irm_id, generation, mask, offset, false);
 }
 
 /**
@@ -322,7 +324,7 @@ static void deallocate_channel(struct fw_card *card, int irm_id,
  */
 void fw_iso_resource_manage(struct fw_card *card, int generation,
                             u64 channels_mask, int *channel, int *bandwidth,
-                            bool allocate, __be32 buffer[2])
+                            bool allocate)
 {
         u32 channels_hi = channels_mask;        /* channels 31...0 */
         u32 channels_lo = channels_mask >> 32;  /* channels 63...32 */
@@ -335,11 +337,11 @@ void fw_iso_resource_manage(struct fw_card *card, int generation,
         if (channels_hi)
                 c = manage_channel(card, irm_id, generation, channels_hi,
                                 CSR_REGISTER_BASE + CSR_CHANNELS_AVAILABLE_HI,
-                                allocate, buffer);
+                                allocate);
         if (channels_lo && c < 0) {
                 c = manage_channel(card, irm_id, generation, channels_lo,
                                 CSR_REGISTER_BASE + CSR_CHANNELS_AVAILABLE_LO,
-                                allocate, buffer);
+                                allocate);
                 if (c >= 0)
                         c += 32;
         }
@@ -351,14 +353,13 @@ void fw_iso_resource_manage(struct fw_card *card, int generation,
         if (*bandwidth == 0)
                 return;
 
-        ret = manage_bandwidth(card, irm_id, generation, *bandwidth,
-                               allocate, buffer);
+        ret = manage_bandwidth(card, irm_id, generation, *bandwidth, allocate);
         if (ret < 0)
                 *bandwidth = 0;
 
         if (allocate && ret < 0) {
                 if (c >= 0)
-                        deallocate_channel(card, irm_id, generation, c, buffer);
+                        deallocate_channel(card, irm_id, generation, c);
                 *channel = ret;
         }
 }
diff --git a/drivers/firewire/core-transaction.c b/drivers/firewire/core-transaction.c
index d00f8ce902cc..77275fdf6c1f 100644
--- a/drivers/firewire/core-transaction.c
+++ b/drivers/firewire/core-transaction.c
@@ -326,8 +326,8 @@ static int allocate_tlabel(struct fw_card *card)
  * It will contain tag, channel, and sy data instead of a node ID then.
  *
  * The payload buffer at @data is going to be DMA-mapped except in case of
- * quadlet-sized payload or of local (loopback) requests.  Hence make sure that
- * the buffer complies with the restrictions for DMA-mapped memory.  The
+ * @length <= 8 or of local (loopback) requests.  Hence make sure that the
+ * buffer complies with the restrictions of the streaming DMA mapping API.
  * @payload must not be freed before the @callback is called.
  *
  * In case of request types without payload, @data is NULL and @length is 0.
@@ -411,7 +411,8 @@ static void transaction_callback(struct fw_card *card, int rcode,
  *
  * Returns the RCODE.  See fw_send_request() for parameter documentation.
  * Unlike fw_send_request(), @data points to the payload of the request or/and
- * to the payload of the response.
+ * to the payload of the response.  DMA mapping restrictions apply to outbound
+ * request payloads of >= 8 bytes but not to inbound response payloads.
  */
 int fw_run_transaction(struct fw_card *card, int tcode, int destination_id,
                        int generation, int speed, unsigned long long offset,
diff --git a/drivers/media/dvb/firewire/firedtv-avc.c b/drivers/media/dvb/firewire/firedtv-avc.c
index fc5ccd8c923a..21c52e3b522e 100644
--- a/drivers/media/dvb/firewire/firedtv-avc.c
+++ b/drivers/media/dvb/firewire/firedtv-avc.c
@@ -1320,14 +1320,10 @@ static int cmp_read(struct firedtv *fdtv, u64 addr, __be32 *data)
 {
         int ret;
 
-        mutex_lock(&fdtv->avc_mutex);
-
         ret = fdtv_read(fdtv, addr, data);
         if (ret < 0)
                 dev_err(fdtv->device, "CMP: read I/O error\n");
 
-        mutex_unlock(&fdtv->avc_mutex);
-
         return ret;
 }
 
@@ -1335,18 +1331,9 @@ static int cmp_lock(struct firedtv *fdtv, u64 addr, __be32 data[])
 {
         int ret;
 
-        mutex_lock(&fdtv->avc_mutex);
-
-        /* data[] is stack-allocated and should not be DMA-mapped. */
-        memcpy(fdtv->avc_data, data, 8);
-
-        ret = fdtv_lock(fdtv, addr, fdtv->avc_data);
+        ret = fdtv_lock(fdtv, addr, data);
         if (ret < 0)
                 dev_err(fdtv->device, "CMP: lock I/O error\n");
-        else
-                memcpy(data, fdtv->avc_data, 8);
-
-        mutex_unlock(&fdtv->avc_mutex);
 
         return ret;
 }
diff --git a/include/linux/firewire.h b/include/linux/firewire.h
index c64f3680d4f1..de90e1ff8488 100644
--- a/include/linux/firewire.h
+++ b/include/linux/firewire.h
@@ -125,7 +125,6 @@ struct fw_card {
         struct delayed_work bm_work; /* bus manager job */
         int bm_retries;
         int bm_generation;
-        __be32 bm_transaction_data[2];
         int bm_node_id;
         bool bm_abdicate;
 
@@ -447,6 +446,6 @@ int fw_iso_context_stop(struct fw_iso_context *ctx);
 void fw_iso_context_destroy(struct fw_iso_context *ctx);
 void fw_iso_resource_manage(struct fw_card *card, int generation,
                             u64 channels_mask, int *channel, int *bandwidth,
-                            bool allocate, __be32 buffer[2]);
+                            bool allocate);
 
 #endif /* _LINUX_FIREWIRE_H */
diff --git a/sound/firewire/cmp.c b/sound/firewire/cmp.c
index 4a37f3a6fab9..14cacbc655dd 100644
--- a/sound/firewire/cmp.c
+++ b/sound/firewire/cmp.c
@@ -49,10 +49,9 @@ static int pcr_modify(struct cmp_connection *c,
                       enum bus_reset_handling bus_reset_handling)
 {
         struct fw_device *device = fw_parent_device(c->resources.unit);
-        __be32 *buffer = c->resources.buffer;
         int generation = c->resources.generation;
         int rcode, errors = 0;
-        __be32 old_arg;
+        __be32 old_arg, buffer[2];
         int err;
 
         buffer[0] = c->last_pcr_value;
diff --git a/sound/firewire/iso-resources.c b/sound/firewire/iso-resources.c
index 775dbd5f3445..bb9c0c1fb529 100644
--- a/sound/firewire/iso-resources.c
+++ b/sound/firewire/iso-resources.c
@@ -11,7 +11,6 @@
 #include <linux/jiffies.h>
 #include <linux/mutex.h>
 #include <linux/sched.h>
-#include <linux/slab.h>
 #include <linux/spinlock.h>
 #include "iso-resources.h"
 
@@ -25,10 +24,6 @@
  */
 int fw_iso_resources_init(struct fw_iso_resources *r, struct fw_unit *unit)
 {
-        r->buffer = kmalloc(2 * 4, GFP_KERNEL);
-        if (!r->buffer)
-                return -ENOMEM;
-
         r->channels_mask = ~0uLL;
         r->unit = fw_unit_get(unit);
         mutex_init(&r->mutex);
@@ -44,7 +39,6 @@ int fw_iso_resources_init(struct fw_iso_resources *r, struct fw_unit *unit)
 void fw_iso_resources_destroy(struct fw_iso_resources *r)
 {
         WARN_ON(r->allocated);
-        kfree(r->buffer);
         mutex_destroy(&r->mutex);
         fw_unit_put(r->unit);
 }
@@ -131,7 +125,7 @@ retry_after_bus_reset:
 
         bandwidth = r->bandwidth + r->bandwidth_overhead;
         fw_iso_resource_manage(card, r->generation, r->channels_mask,
-                               &channel, &bandwidth, true, r->buffer);
+                               &channel, &bandwidth, true);
         if (channel == -EAGAIN) {
                 mutex_unlock(&r->mutex);
                 goto retry_after_bus_reset;
@@ -184,7 +178,7 @@ int fw_iso_resources_update(struct fw_iso_resources *r)
         bandwidth = r->bandwidth + r->bandwidth_overhead;
 
         fw_iso_resource_manage(card, r->generation, 1uLL << r->channel,
-                               &channel, &bandwidth, true, r->buffer);
+                               &channel, &bandwidth, true);
         /*
          * When another bus reset happens, pretend that the allocation
          * succeeded; we will try again for the new generation later.
@@ -220,7 +214,7 @@ void fw_iso_resources_free(struct fw_iso_resources *r)
         if (r->allocated) {
                 bandwidth = r->bandwidth + r->bandwidth_overhead;
                 fw_iso_resource_manage(card, r->generation, 1uLL << r->channel,
-                                       &channel, &bandwidth, false, r->buffer);
+                                       &channel, &bandwidth, false);
                 if (channel < 0)
                         dev_err(&r->unit->device,
                                 "isochronous resource deallocation failed\n");
diff --git a/sound/firewire/iso-resources.h b/sound/firewire/iso-resources.h
index 3f0730e4d841..5a9af7c61657 100644
--- a/sound/firewire/iso-resources.h
+++ b/sound/firewire/iso-resources.h
@@ -24,7 +24,6 @@ struct fw_iso_resources {
         unsigned int bandwidth_overhead;
         int generation; /* in which allocation is valid */
         bool allocated;
-        __be32 *buffer;
 };
 
 int fw_iso_resources_init(struct fw_iso_resources *r,