K 10
svn:author
V 8
lstewart
K 8
svn:date
V 27
2009-10-06T07:24:23.419713Z
K 7
svn:log
V 765
Cannibalise an unused field in the ALE to store a count of the bytes written to
the ALE by the consumer. This extends the alq_get/alq_post interface to allow a
consumer to request an allocation from the ALQ that may be larger than is
actually needed. Nothing changes in the default use case. The new use case made
possible by this change is as follows:
 - Consumer requests X bytes from the ALQ using alq_getn().
 - Consumer only generates Y bytes of data (where Y < X) and writes them to
   the ALQ buffer location pointed to by ale->ae_data.
 - [New step] Consumer overwrites ale->ae_bytesused with the value of Y to
   inform alq_post() of the actual number of bytes written.
 - Consumer calls alq_post() to complete the write.

Sponsored by:	FreeBSD Foundation

END