diff options
| author | Eli Billauer <eli.billauer@gmail.com> | 2016-02-24 10:40:51 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2016-03-05 12:19:39 -0800 |
| commit | ba327173ef48c12cf6f326441c74f373fa3be220 (patch) | |
| tree | d026f0eb8411ea9c98b59271a4a06ebf0c3d5c1e /drivers/char | |
| parent | a75fa128236bc2fdaa5e412145cbd577e42e14c2 (diff) | |
| download | linux-ba327173ef48c12cf6f326441c74f373fa3be220.tar.gz | |
char: xillybus: Fix internal data structure initialization
A couple of fields in a data structure, which is used by the driver only,
were not initialized properly during the driver's setup.
The primary issue with this bug was that channel->wr_buf_size remained zero,
so calls to dma_sync_single_for_cpu() took place with zero size, and
consequently did nothing.
This had a rather minimal practical impact, because
(a) these calls are NOPs on Intel/AMD platforms, as well as other platforms
with coherent cache, and
(b) it's extremely rare that any cache line would survive between two reads
from a given DMA buffer
Hence no significant practical difference is expected with this patch.
Signed-off-by: Eli Billauer <eli.billauer@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/char')
| -rw-r--r-- | drivers/char/xillybus/xillybus_core.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/drivers/char/xillybus/xillybus_core.c b/drivers/char/xillybus/xillybus_core.c index 77d6c127e691..dcd19f3f182e 100644 --- a/drivers/char/xillybus/xillybus_core.c +++ b/drivers/char/xillybus/xillybus_core.c @@ -509,7 +509,7 @@ static int xilly_setupchannels(struct xilly_endpoint *ep, channel->log2_element_size = ((format > 2) ? 2 : format); - bytebufsize = channel->rd_buf_size = bufsize * + bytebufsize = bufsize * (1 << channel->log2_element_size); buffers = devm_kcalloc(dev, bufnum, @@ -523,6 +523,7 @@ static int xilly_setupchannels(struct xilly_endpoint *ep, if (!is_writebuf) { channel->num_rd_buffers = bufnum; + channel->rd_buf_size = bytebufsize; channel->rd_allow_partial = allowpartial; channel->rd_synchronous = synchronous; channel->rd_exclusive_open = exclusive_open; @@ -533,6 +534,7 @@ static int xilly_setupchannels(struct xilly_endpoint *ep, bufnum, bytebufsize); } else if (channelnum > 0) { channel->num_wr_buffers = bufnum; + channel->wr_buf_size = bytebufsize; channel->seekable = seekable; channel->wr_supports_nonempty = supports_nonempty; |