diff options
Diffstat (limited to 'drivers/firewire/fw-ohci.c')
| -rw-r--r-- | drivers/firewire/fw-ohci.c | 73 |
1 files changed, 35 insertions, 38 deletions
diff --git a/drivers/firewire/fw-ohci.c b/drivers/firewire/fw-ohci.c index 6d19828a93a5..bbfd6cdac668 100644 --- a/drivers/firewire/fw-ohci.c +++ b/drivers/firewire/fw-ohci.c @@ -1765,6 +1765,28 @@ ohci_get_bus_time(struct fw_card *card) return bus_time; } +static void copy_iso_headers(struct iso_context *ctx, void *p) +{ + int i = ctx->header_length; + + if (i + ctx->base.header_size > PAGE_SIZE) + return; + + /* + * The iso header is byteswapped to little endian by + * the controller, but the remaining header quadlets + * are big endian. We want to present all the headers + * as big endian, so we have to swap the first quadlet. + */ + if (ctx->base.header_size > 0) + *(u32 *) (ctx->header + i) = __swab32(*(u32 *) (p + 4)); + if (ctx->base.header_size > 4) + *(u32 *) (ctx->header + i + 4) = __swab32(*(u32 *) p); + if (ctx->base.header_size > 8) + memcpy(ctx->header + i + 8, p + 8, ctx->base.header_size - 8); + ctx->header_length += ctx->base.header_size; +} + static int handle_ir_dualbuffer_packet(struct context *context, struct descriptor *d, struct descriptor *last) @@ -1775,7 +1797,6 @@ static int handle_ir_dualbuffer_packet(struct context *context, __le32 *ir_header; size_t header_length; void *p, *end; - int i; if (db->first_res_count != 0 && db->second_res_count != 0) { if (ctx->excess_bytes <= le16_to_cpu(db->second_req_count)) { @@ -1788,25 +1809,14 @@ static int handle_ir_dualbuffer_packet(struct context *context, header_length = le16_to_cpu(db->first_req_count) - le16_to_cpu(db->first_res_count); - i = ctx->header_length; p = db + 1; end = p + header_length; - while (p < end && i + ctx->base.header_size <= PAGE_SIZE) { - /* - * The iso header is byteswapped to little endian by - * the controller, but the remaining header quadlets - * are big endian. We want to present all the headers - * as big endian, so we have to swap the first - * quadlet. - */ - *(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; + while (p < end) { + copy_iso_headers(ctx, p); ctx->excess_bytes += (le32_to_cpu(*(__le32 *)(p + 4)) >> 16) & 0xffff; - p += ctx->base.header_size + 4; + p += max(ctx->base.header_size, (size_t)8); } - ctx->header_length = i; ctx->excess_bytes -= le16_to_cpu(db->second_req_count) - le16_to_cpu(db->second_res_count); @@ -1832,7 +1842,6 @@ static int handle_ir_packet_per_buffer(struct context *context, struct descriptor *pd; __le32 *ir_header; void *p; - int i; for (pd = d; pd <= last; pd++) { if (pd->transfer_status) @@ -1842,21 +1851,8 @@ static int handle_ir_packet_per_buffer(struct context *context, /* Descriptor(s) not done yet, stop iteration */ return 0; - i = ctx->header_length; - p = last + 1; - - 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 - * are big endian. We want to present all the headers - * as big endian, so we have to swap the first quadlet. - */ - *(u32 *) (ctx->header + i) = __swab32(*(u32 *) (p + 4)); - memcpy(ctx->header + i + 4, p + 8, ctx->base.header_size - 4); - ctx->header_length += ctx->base.header_size; - } + p = last + 1; + copy_iso_headers(ctx, p); if (le16_to_cpu(last->control) & DESCRIPTOR_IRQ_ALWAYS) { ir_header = (__le32 *) p; @@ -2151,11 +2147,11 @@ ohci_queue_iso_receive_dualbuffer(struct fw_iso_context *base, z = 2; /* - * The OHCI controller puts the status word in the header - * buffer too, so we need 4 extra bytes per packet. + * The OHCI controller puts the isochronous header and trailer in the + * buffer, so we need at least 8 bytes. */ packet_count = p->header_length / ctx->base.header_size; - header_size = packet_count * (ctx->base.header_size + 4); + header_size = packet_count * max(ctx->base.header_size, (size_t)8); /* Get header size in number of descriptors. */ header_z = DIV_ROUND_UP(header_size, sizeof(*d)); @@ -2173,7 +2169,8 @@ ohci_queue_iso_receive_dualbuffer(struct fw_iso_context *base, db = (struct db_descriptor *) d; db->control = cpu_to_le16(DESCRIPTOR_STATUS | DESCRIPTOR_BRANCH_ALWAYS); - db->first_size = cpu_to_le16(ctx->base.header_size + 4); + db->first_size = + cpu_to_le16(max(ctx->base.header_size, (size_t)8)); if (p->skip && rest == p->payload_length) { db->control |= cpu_to_le16(DESCRIPTOR_WAIT); db->first_req_count = db->first_size; @@ -2223,11 +2220,11 @@ ohci_queue_iso_receive_packet_per_buffer(struct fw_iso_context *base, 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. + * The OHCI controller puts the isochronous header and trailer in the + * buffer, so we need at least 8 bytes. */ packet_count = p->header_length / ctx->base.header_size; - header_size = ctx->base.header_size + 4; + header_size = max(ctx->base.header_size, (size_t)8); /* Get header size in number of descriptors. */ header_z = DIV_ROUND_UP(header_size, sizeof(*d)); |
