firewire: endianess fix
[sfrench/cifs-2.6.git] / drivers / firewire / fw-ohci.c
index a44d16d0c50575da616501ebc0b11f265bdc6cce..ed4e3573e72c48a92c6f9829bee021dd8c941b88 100644 (file)
@@ -98,17 +98,48 @@ struct context;
 typedef int (*descriptor_callback_t)(struct context *ctx,
                                     struct descriptor *d,
                                     struct descriptor *last);
+
+/*
+ * A buffer that contains a block of DMA-able coherent memory used for
+ * storing a portion of a DMA descriptor program.
+ */
+struct descriptor_buffer {
+       struct list_head list;
+       dma_addr_t buffer_bus;
+       size_t buffer_size;
+       size_t used;
+       struct descriptor buffer[0];
+};
+
 struct context {
        struct fw_ohci *ohci;
        u32 regs;
+       int total_allocation;
 
-       struct descriptor *buffer;
-       dma_addr_t buffer_bus;
-       size_t buffer_size;
-       struct descriptor *head_descriptor;
-       struct descriptor *tail_descriptor;
-       struct descriptor *tail_descriptor_last;
-       struct descriptor *prev_descriptor;
+       /*
+        * List of page-sized buffers for storing DMA descriptors.
+        * Head of list contains buffers in use and tail of list contains
+        * free buffers.
+        */
+       struct list_head buffer_list;
+
+       /*
+        * Pointer to a buffer inside buffer_list that contains the tail
+        * end of the current DMA program.
+        */
+       struct descriptor_buffer *buffer_tail;
+
+       /*
+        * The descriptor containing the branch address of the first
+        * descriptor that has not yet been filled by the device.
+        */
+       struct descriptor *last;
+
+       /*
+        * The last descriptor in the DMA program.  It contains the branch
+        * address that must be updated upon appending a new descriptor.
+        */
+       struct descriptor *prev;
 
        descriptor_callback_t callback;
 
@@ -198,8 +229,6 @@ static inline struct fw_ohci *fw_ohci(struct fw_card *card)
 #define SELF_ID_BUF_SIZE               0x800
 #define OHCI_TCODE_PHY_PACKET          0x0e
 #define OHCI_VERSION_1_1               0x010010
-#define ISO_BUFFER_SIZE                        (64 * 1024)
-#define AT_BUFFER_SIZE                 4096
 
 static char ohci_driver_name[] = KBUILD_MODNAME;
 
@@ -346,7 +375,7 @@ static __le32 *handle_ar_packet(struct ar_context *ctx, __le32 *buffer)
         */
 
        if (p.ack + 16 == 0x09)
-               ohci->request_generation = (buffer[2] >> 16) & 0xff;
+               ohci->request_generation = (p.header[2] >> 16) & 0xff;
        else if (ctx == &ohci->ar_request_ctx)
                fw_core_handle_request(&ohci->card, &p);
        else
@@ -456,71 +485,108 @@ find_branch_descriptor(struct descriptor *d, int z)
 static void context_tasklet(unsigned long data)
 {
        struct context *ctx = (struct context *) data;
-       struct fw_ohci *ohci = ctx->ohci;
        struct descriptor *d, *last;
        u32 address;
        int z;
+       struct descriptor_buffer *desc;
 
-       dma_sync_single_for_cpu(ohci->card.device, ctx->buffer_bus,
-                               ctx->buffer_size, DMA_TO_DEVICE);
-
-       d    = ctx->tail_descriptor;
-       last = ctx->tail_descriptor_last;
-
+       desc = list_entry(ctx->buffer_list.next,
+                       struct descriptor_buffer, list);
+       last = ctx->last;
        while (last->branch_address != 0) {
+               struct descriptor_buffer *old_desc = desc;
                address = le32_to_cpu(last->branch_address);
                z = address & 0xf;
-               d = ctx->buffer + (address - ctx->buffer_bus) / sizeof(*d);
+               address &= ~0xf;
+
+               /* If the branch address points to a buffer outside of the
+                * current buffer, advance to the next buffer. */
+               if (address < desc->buffer_bus ||
+                               address >= desc->buffer_bus + desc->used)
+                       desc = list_entry(desc->list.next,
+                                       struct descriptor_buffer, list);
+               d = desc->buffer + (address - desc->buffer_bus) / sizeof(*d);
                last = find_branch_descriptor(d, z);
 
                if (!ctx->callback(ctx, d, last))
                        break;
 
-               ctx->tail_descriptor      = d;
-               ctx->tail_descriptor_last = last;
+               if (old_desc != desc) {
+                       /* If we've advanced to the next buffer, move the
+                        * previous buffer to the free list. */
+                       unsigned long flags;
+                       old_desc->used = 0;
+                       spin_lock_irqsave(&ctx->ohci->lock, flags);
+                       list_move_tail(&old_desc->list, &ctx->buffer_list);
+                       spin_unlock_irqrestore(&ctx->ohci->lock, flags);
+               }
+               ctx->last = last;
        }
 }
 
+/*
+ * Allocate a new buffer and add it to the list of free buffers for this
+ * context.  Must be called with ohci->lock held.
+ */
+static int
+context_add_buffer(struct context *ctx)
+{
+       struct descriptor_buffer *desc;
+       dma_addr_t bus_addr;
+       int offset;
+
+       /*
+        * 16MB of descriptors should be far more than enough for any DMA
+        * program.  This will catch run-away userspace or DoS attacks.
+        */
+       if (ctx->total_allocation >= 16*1024*1024)
+               return -ENOMEM;
+
+       desc = dma_alloc_coherent(ctx->ohci->card.device, PAGE_SIZE,
+                       &bus_addr, GFP_ATOMIC);
+       if (!desc)
+               return -ENOMEM;
+
+       offset = (void *)&desc->buffer - (void *)desc;
+       desc->buffer_size = PAGE_SIZE - offset;
+       desc->buffer_bus = bus_addr + offset;
+       desc->used = 0;
+
+       list_add_tail(&desc->list, &ctx->buffer_list);
+       ctx->total_allocation += PAGE_SIZE;
+
+       return 0;
+}
+
 static int
 context_init(struct context *ctx, struct fw_ohci *ohci,
-            size_t buffer_size, u32 regs,
-            descriptor_callback_t callback)
+            u32 regs, descriptor_callback_t callback)
 {
        ctx->ohci = ohci;
        ctx->regs = regs;
-       ctx->buffer_size = buffer_size;
-       ctx->buffer = kmalloc(buffer_size, GFP_KERNEL);
-       if (ctx->buffer == NULL)
+       ctx->total_allocation = 0;
+
+       INIT_LIST_HEAD(&ctx->buffer_list);
+       if (context_add_buffer(ctx) < 0)
                return -ENOMEM;
 
+       ctx->buffer_tail = list_entry(ctx->buffer_list.next,
+                       struct descriptor_buffer, list);
+
        tasklet_init(&ctx->tasklet, context_tasklet, (unsigned long)ctx);
        ctx->callback = callback;
 
-       ctx->buffer_bus =
-               dma_map_single(ohci->card.device, ctx->buffer,
-                              buffer_size, DMA_TO_DEVICE);
-       if (dma_mapping_error(ctx->buffer_bus)) {
-               kfree(ctx->buffer);
-               return -ENOMEM;
-       }
-
-       ctx->head_descriptor      = ctx->buffer;
-       ctx->prev_descriptor      = ctx->buffer;
-       ctx->tail_descriptor      = ctx->buffer;
-       ctx->tail_descriptor_last = ctx->buffer;
-
        /*
         * We put a dummy descriptor in the buffer that has a NULL
         * branch address and looks like it's been sent.  That way we
-        * have a descriptor to append DMA programs to.  Also, the
-        * ring buffer invariant is that it always has at least one
-        * element so that head == tail means buffer full.
+        * have a descriptor to append DMA programs to.
         */
-
-       memset(ctx->head_descriptor, 0, sizeof(*ctx->head_descriptor));
-       ctx->head_descriptor->control = cpu_to_le16(DESCRIPTOR_OUTPUT_LAST);
-       ctx->head_descriptor->transfer_status = cpu_to_le16(0x8011);
-       ctx->head_descriptor++;
+       memset(ctx->buffer_tail->buffer, 0, sizeof(*ctx->buffer_tail->buffer));
+       ctx->buffer_tail->buffer->control = cpu_to_le16(DESCRIPTOR_OUTPUT_LAST);
+       ctx->buffer_tail->buffer->transfer_status = cpu_to_le16(0x8011);
+       ctx->buffer_tail->used += sizeof(*ctx->buffer_tail->buffer);
+       ctx->last = ctx->buffer_tail->buffer;
+       ctx->prev = ctx->buffer_tail->buffer;
 
        return 0;
 }
@@ -529,35 +595,42 @@ static void
 context_release(struct context *ctx)
 {
        struct fw_card *card = &ctx->ohci->card;
+       struct descriptor_buffer *desc, *tmp;
 
-       dma_unmap_single(card->device, ctx->buffer_bus,
-                        ctx->buffer_size, DMA_TO_DEVICE);
-       kfree(ctx->buffer);
+       list_for_each_entry_safe(desc, tmp, &ctx->buffer_list, list)
+               dma_free_coherent(card->device, PAGE_SIZE, desc,
+                       desc->buffer_bus -
+                       ((void *)&desc->buffer - (void *)desc));
 }
 
+/* Must be called with ohci->lock held */
 static struct descriptor *
 context_get_descriptors(struct context *ctx, int z, dma_addr_t *d_bus)
 {
-       struct descriptor *d, *tail, *end;
-
-       d = ctx->head_descriptor;
-       tail = ctx->tail_descriptor;
-       end = ctx->buffer + ctx->buffer_size / sizeof(*d);
-
-       if (d + z <= tail) {
-               goto has_space;
-       } else if (d > tail && d + z <= end) {
-               goto has_space;
-       } else if (d > tail && ctx->buffer + z <= tail) {
-               d = ctx->buffer;
-               goto has_space;
-       }
+       struct descriptor *d = NULL;
+       struct descriptor_buffer *desc = ctx->buffer_tail;
+
+       if (z * sizeof(*d) > desc->buffer_size)
+               return NULL;
 
-       return NULL;
+       if (z * sizeof(*d) > desc->buffer_size - desc->used) {
+               /* No room for the descriptor in this buffer, so advance to the
+                * next one. */
 
- has_space:
+               if (desc->list.next == &ctx->buffer_list) {
+                       /* If there is no free buffer next in the list,
+                        * allocate one. */
+                       if (context_add_buffer(ctx) < 0)
+                               return NULL;
+               }
+               desc = list_entry(desc->list.next,
+                               struct descriptor_buffer, list);
+               ctx->buffer_tail = desc;
+       }
+
+       d = desc->buffer + desc->used / sizeof(*d);
        memset(d, 0, z * sizeof(*d));
-       *d_bus = ctx->buffer_bus + (d - ctx->buffer) * sizeof(*d);
+       *d_bus = desc->buffer_bus + desc->used;
 
        return d;
 }
@@ -567,7 +640,7 @@ static void context_run(struct context *ctx, u32 extra)
        struct fw_ohci *ohci = ctx->ohci;
 
        reg_write(ohci, COMMAND_PTR(ctx->regs),
-                 le32_to_cpu(ctx->tail_descriptor_last->branch_address));
+                 le32_to_cpu(ctx->last->branch_address));
        reg_write(ohci, CONTROL_CLEAR(ctx->regs), ~0);
        reg_write(ohci, CONTROL_SET(ctx->regs), CONTEXT_RUN | extra);
        flush_writes(ohci);
@@ -577,15 +650,13 @@ static void context_append(struct context *ctx,
                           struct descriptor *d, int z, int extra)
 {
        dma_addr_t d_bus;
+       struct descriptor_buffer *desc = ctx->buffer_tail;
 
-       d_bus = ctx->buffer_bus + (d - ctx->buffer) * sizeof(*d);
-
-       ctx->head_descriptor = d + z + extra;
-       ctx->prev_descriptor->branch_address = cpu_to_le32(d_bus | z);
-       ctx->prev_descriptor = find_branch_descriptor(d, z);
+       d_bus = desc->buffer_bus + (d - desc->buffer) * sizeof(*d);
 
-       dma_sync_single_for_device(ctx->ohci->card.device, ctx->buffer_bus,
-                                  ctx->buffer_size, DMA_TO_DEVICE);
+       desc->used += (z + extra) * sizeof(*d);
+       ctx->prev->branch_address = cpu_to_le32(d_bus | z);
+       ctx->prev = find_branch_descriptor(d, z);
 
        reg_write(ctx->ohci, CONTROL_SET(ctx->regs), CONTEXT_WAKE);
        flush_writes(ctx->ohci);
@@ -1079,6 +1150,13 @@ static irqreturn_t irq_handler(int irq, void *data)
        if (unlikely(event & OHCI1394_postedWriteErr))
                fw_error("PCI posted write error\n");
 
+       if (unlikely(event & OHCI1394_cycleTooLong)) {
+               if (printk_ratelimit())
+                       fw_notify("isochronous cycle too long\n");
+               reg_write(ohci, OHCI1394_LinkControlSet,
+                         OHCI1394_LinkControl_cycleMaster);
+       }
+
        if (event & OHCI1394_cycle64Seconds) {
                cycle_time = reg_read(ohci, OHCI1394_IsochronousCycleTimer);
                if ((cycle_time & 0x80000000) == 0)
@@ -1152,8 +1230,8 @@ static int ohci_enable(struct fw_card *card, u32 *config_rom, size_t length)
                  OHCI1394_RQPkt | OHCI1394_RSPkt |
                  OHCI1394_reqTxComplete | OHCI1394_respTxComplete |
                  OHCI1394_isochRx | OHCI1394_isochTx |
-                 OHCI1394_postedWriteErr | OHCI1394_cycle64Seconds |
-                 OHCI1394_masterIntEnable);
+                 OHCI1394_postedWriteErr | OHCI1394_cycleTooLong |
+                 OHCI1394_cycle64Seconds | OHCI1394_masterIntEnable);
 
        /* Activate link_on bit and contender bit in our self ID packets.*/
        if (ohci_update_phy_reg(card, 4, 0,
@@ -1461,24 +1539,24 @@ static int handle_ir_packet_per_buffer(struct context *context,
 {
        struct iso_context *ctx =
                container_of(context, struct iso_context, context);
-       struct descriptor *pd = d + 1;
+       struct descriptor *pd;
        __le32 *ir_header;
-       size_t header_length;
-       void *p, *end;
-       int i, z;
+       void *p;
+       int i;
 
-       if (pd->res_count == pd->req_count)
+       for (pd = d; pd <= last; pd++) {
+               if (pd->transfer_status)
+                       break;
+       }
+       if (pd > last)
                /* Descriptor(s) not done yet, stop iteration */
                return 0;
 
-       header_length = le16_to_cpu(d->req_count);
-
        i   = ctx->header_length;
-       z   = le32_to_cpu(pd->branch_address) & 0xf;
-       p   = d + z;
-       end = p + header_length;
+       p   = last + 1;
 
-       while (p < end && i + ctx->base.header_size <= PAGE_SIZE) {
+       if (ctx->base.header_size > 0 &&
+                       i + ctx->base.header_size <= PAGE_SIZE) {
                /*
                 * The iso header is byteswapped to little endian by
                 * the controller, but the remaining header quadlets
@@ -1487,14 +1565,11 @@ static int handle_ir_packet_per_buffer(struct context *context,
                 */
                *(u32 *) (ctx->header + i) = __swab32(*(u32 *) (p + 4));
                memcpy(ctx->header + i + 4, p + 8, ctx->base.header_size - 4);
-               i += ctx->base.header_size;
-               p += ctx->base.header_size + 4;
+               ctx->header_length += ctx->base.header_size;
        }
 
-       ctx->header_length = i;
-
-       if (le16_to_cpu(pd->control) & DESCRIPTOR_IRQ_ALWAYS) {
-               ir_header = (__le32 *) (d + z);
+       if (le16_to_cpu(last->control) & DESCRIPTOR_IRQ_ALWAYS) {
+               ir_header = (__le32 *) p;
                ctx->base.callback(&ctx->base,
                                   le32_to_cpu(ir_header[0]) & 0xffff,
                                   ctx->header_length, ctx->header,
@@ -1502,7 +1577,6 @@ static int handle_ir_packet_per_buffer(struct context *context,
                ctx->header_length = 0;
        }
 
-
        return 1;
 }
 
@@ -1568,8 +1642,7 @@ ohci_allocate_iso_context(struct fw_card *card, int type, size_t header_size)
        if (ctx->header == NULL)
                goto out;
 
-       retval = context_init(&ctx->context, ohci, ISO_BUFFER_SIZE,
-                             regs, callback);
+       retval = context_init(&ctx->context, ohci, regs, callback);
        if (retval < 0)
                goto out_with_header;
 
@@ -1853,67 +1926,70 @@ ohci_queue_iso_receive_packet_per_buffer(struct fw_iso_context *base,
 {
        struct iso_context *ctx = container_of(base, struct iso_context, base);
        struct descriptor *d = NULL, *pd = NULL;
-       struct fw_iso_packet *p;
+       struct fw_iso_packet *p = packet;
        dma_addr_t d_bus, page_bus;
        u32 z, header_z, rest;
-       int i, page, offset, packet_count, header_size;
-
-       if (packet->skip) {
-               d = context_get_descriptors(&ctx->context, 1, &d_bus);
-               if (d == NULL)
-                       return -ENOMEM;
-
-               d->control = cpu_to_le16(DESCRIPTOR_STATUS |
-                                        DESCRIPTOR_INPUT_LAST |
-                                        DESCRIPTOR_BRANCH_ALWAYS |
-                                        DESCRIPTOR_WAIT);
-               context_append(&ctx->context, d, 1, 0);
-       }
-
-       /* one descriptor for header, one for payload */
-       /* FIXME: handle cases where we need multiple desc. for payload */
-       z = 2;
-       p = packet;
+       int i, j, length;
+       int page, offset, packet_count, header_size, payload_per_buffer;
 
        /*
         * The OHCI controller puts the status word in the
         * buffer too, so we need 4 extra bytes per packet.
         */
        packet_count = p->header_length / ctx->base.header_size;
-       header_size  = packet_count * (ctx->base.header_size + 4);
+       header_size  = ctx->base.header_size + 4;
 
        /* Get header size in number of descriptors. */
        header_z = DIV_ROUND_UP(header_size, sizeof(*d));
        page     = payload >> PAGE_SHIFT;
        offset   = payload & ~PAGE_MASK;
-       rest     = p->payload_length;
+       payload_per_buffer = p->payload_length / packet_count;
 
        for (i = 0; i < packet_count; i++) {
                /* d points to the header descriptor */
+               z = DIV_ROUND_UP(payload_per_buffer + offset, PAGE_SIZE) + 1;
                d = context_get_descriptors(&ctx->context,
-                                           z + header_z, &d_bus);
+                               z + header_z, &d_bus);
                if (d == NULL)
                        return -ENOMEM;
 
-               d->control      = cpu_to_le16(DESCRIPTOR_INPUT_MORE);
+               d->control      = cpu_to_le16(DESCRIPTOR_STATUS |
+                                             DESCRIPTOR_INPUT_MORE);
+               if (p->skip && i == 0)
+                       d->control |= cpu_to_le16(DESCRIPTOR_WAIT);
                d->req_count    = cpu_to_le16(header_size);
                d->res_count    = d->req_count;
+               d->transfer_status = 0;
                d->data_address = cpu_to_le32(d_bus + (z * sizeof(*d)));
 
-               /* pd points to the payload descriptor */
-               pd = d + 1;
+               rest = payload_per_buffer;
+               for (j = 1; j < z; j++) {
+                       pd = d + j;
+                       pd->control = cpu_to_le16(DESCRIPTOR_STATUS |
+                                                 DESCRIPTOR_INPUT_MORE);
+
+                       if (offset + rest < PAGE_SIZE)
+                               length = rest;
+                       else
+                               length = PAGE_SIZE - offset;
+                       pd->req_count = cpu_to_le16(length);
+                       pd->res_count = pd->req_count;
+                       pd->transfer_status = 0;
+
+                       page_bus = page_private(buffer->pages[page]);
+                       pd->data_address = cpu_to_le32(page_bus + offset);
+
+                       offset = (offset + length) & ~PAGE_MASK;
+                       rest -= length;
+                       if (offset == 0)
+                               page++;
+               }
                pd->control = cpu_to_le16(DESCRIPTOR_STATUS |
                                          DESCRIPTOR_INPUT_LAST |
                                          DESCRIPTOR_BRANCH_ALWAYS);
-               if (p->interrupt)
+               if (p->interrupt && i == packet_count - 1)
                        pd->control |= cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS);
 
-               pd->req_count = cpu_to_le16(rest);
-               pd->res_count = pd->req_count;
-
-               page_bus = page_private(buffer->pages[page]);
-               pd->data_address = cpu_to_le32(page_bus + offset);
-
                context_append(&ctx->context, d, z, header_z);
        }
 
@@ -1927,16 +2003,22 @@ ohci_queue_iso(struct fw_iso_context *base,
               unsigned long payload)
 {
        struct iso_context *ctx = container_of(base, struct iso_context, base);
+       unsigned long flags;
+       int retval;
 
+       spin_lock_irqsave(&ctx->context.ohci->lock, flags);
        if (base->type == FW_ISO_CONTEXT_TRANSMIT)
-               return ohci_queue_iso_transmit(base, packet, buffer, payload);
+               retval = ohci_queue_iso_transmit(base, packet, buffer, payload);
        else if (ctx->context.ohci->version >= OHCI_VERSION_1_1)
-               return ohci_queue_iso_receive_dualbuffer(base, packet,
+               retval = ohci_queue_iso_receive_dualbuffer(base, packet,
                                                         buffer, payload);
        else
-               return ohci_queue_iso_receive_packet_per_buffer(base, packet,
+               retval = ohci_queue_iso_receive_packet_per_buffer(base, packet,
                                                                buffer,
                                                                payload);
+       spin_unlock_irqrestore(&ctx->context.ohci->lock, flags);
+
+       return retval;
 }
 
 static const struct fw_card_driver ohci_driver = {
@@ -2008,10 +2090,10 @@ pci_probe(struct pci_dev *dev, const struct pci_device_id *ent)
        ar_context_init(&ohci->ar_response_ctx, ohci,
                        OHCI1394_AsRspRcvContextControlSet);
 
-       context_init(&ohci->at_request_ctx, ohci, AT_BUFFER_SIZE,
+       context_init(&ohci->at_request_ctx, ohci,
                     OHCI1394_AsReqTrContextControlSet, handle_at_packet);
 
-       context_init(&ohci->at_response_ctx, ohci, AT_BUFFER_SIZE,
+       context_init(&ohci->at_response_ctx, ohci,
                     OHCI1394_AsRspTrContextControlSet, handle_at_packet);
 
        reg_write(ohci, OHCI1394_IsoRecvIntMaskSet, ~0);