diff options
Diffstat (limited to 'drivers/firewire/ohci.c')
| -rw-r--r-- | drivers/firewire/ohci.c | 18 |
1 files changed, 11 insertions, 7 deletions
diff --git a/drivers/firewire/ohci.c b/drivers/firewire/ohci.c index 8bf89267dc25..45c048751f3b 100644 --- a/drivers/firewire/ohci.c +++ b/drivers/firewire/ohci.c @@ -734,7 +734,7 @@ static unsigned int ar_search_last_active_buffer(struct ar_context *ctx, __le16 res_count, next_res_count; i = ar_first_buffer_index(ctx); - res_count = ACCESS_ONCE(ctx->descriptors[i].res_count); + res_count = READ_ONCE(ctx->descriptors[i].res_count); /* A buffer that is not yet completely filled must be the last one. */ while (i != last && res_count == 0) { @@ -742,8 +742,7 @@ static unsigned int ar_search_last_active_buffer(struct ar_context *ctx, /* Peek at the next descriptor. */ next_i = ar_next_buffer_index(i); rmb(); /* read descriptors in order */ - next_res_count = ACCESS_ONCE( - ctx->descriptors[next_i].res_count); + next_res_count = READ_ONCE(ctx->descriptors[next_i].res_count); /* * If the next descriptor is still empty, we must stop at this * descriptor. @@ -759,8 +758,7 @@ static unsigned int ar_search_last_active_buffer(struct ar_context *ctx, if (MAX_AR_PACKET_SIZE > PAGE_SIZE && i != last) { next_i = ar_next_buffer_index(next_i); rmb(); - next_res_count = ACCESS_ONCE( - ctx->descriptors[next_i].res_count); + next_res_count = READ_ONCE(ctx->descriptors[next_i].res_count); if (next_res_count != cpu_to_le16(PAGE_SIZE)) goto next_buffer_is_active; } @@ -1130,7 +1128,13 @@ static int context_add_buffer(struct context *ctx) return -ENOMEM; offset = (void *)&desc->buffer - (void *)desc; - desc->buffer_size = PAGE_SIZE - offset; + /* + * Some controllers, like JMicron ones, always issue 0x20-byte DMA reads + * for descriptors, even 0x10-byte ones. This can cause page faults when + * an IOMMU is in use and the oversized read crosses a page boundary. + * Work around this by always leaving at least 0x10 bytes of padding. + */ + desc->buffer_size = PAGE_SIZE - offset - 0x10; desc->buffer_bus = bus_addr + offset; desc->used = 0; @@ -2812,7 +2816,7 @@ static int handle_ir_buffer_fill(struct context *context, u32 buffer_dma; req_count = le16_to_cpu(last->req_count); - res_count = le16_to_cpu(ACCESS_ONCE(last->res_count)); + res_count = le16_to_cpu(READ_ONCE(last->res_count)); completed = req_count - res_count; buffer_dma = le32_to_cpu(last->data_address); |