Quoting r. Sean Hefty <[EMAIL PROTECTED]>: > Subject: Re: Re: user_mad: large rmpp length problem > > Hal Rosenstock wrote: > > I also don't think an API change is required in the approach I am > > planning to take. It's in user_mad in how it allocates memory and copies > > into it as well as the underlying mad layer for supporting more than 1 > > sgl entry. If you want to take the ball on this, you/Michael are welcome > > to submit patches to both of these along these lines. Sean can comment > > for himself on this. > > An API change shouldn't be necessary. The plan to support large sends was to > change how the void *mad pointer in struct ib_mad_send_bug is used. > Currently, > it references a single data buffer. The fix is to have it reference a list > of > buffers for large transfers. See: > > http://openib.org/pipermail/openib-general/2005-October/012723.html > > for more details. > > And yes, a patch for this would be great. Otherwise, I will eventually get > to > this, but it may be a few weeks before it bumps up high enough on my priority > list. > > - Sean
This approach still means that we have to allocate a potentially huge amount of memory to copy all of the rmpp mad into kernel in one go. What I had in mind was: add a get_next_segment callback to mad, which would copy the data (by copy_from_user) incrementally, making forward progress without requiring us to have all of the mad in kernel memory. -- MST _______________________________________________ openib-general mailing list [email protected] http://openib.org/mailman/listinfo/openib-general To unsubscribe, please visit http://openib.org/mailman/listinfo/openib-general
