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<TITLE>Error code in "create" functions</TITLE>
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<P><FONT SIZE=2>Hi,</FONT>
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<P><FONT SIZE=2>It appears that in some functions that perform allocation of objects, the new</FONT>
<BR><FONT SIZE=2>object pointer is being returned. For example:</FONT>
<BR> <FONT SIZE=2>struct ib_pd * (*alloc_pd)(struct ib_device *device);</FONT>
<BR> <FONT SIZE=2>struct ib_ah * (*create_ah)(struct ib_pd *pd, struct ib_ah_attr *ah_attr);</FONT>
<BR> <FONT SIZE=2>struct ib_qp * (*create_qp)(struct ib_pd *pd,struct ib_qp_init_attr *qp_init_attr, struct ib_qp_cap *qp_cap);</FONT></P>
<P> <FONT SIZE=2>struct ib_srq * (*create_srq)(struct ib_pd *pd, void *srq_context, struct ib_srq_attr *srq_attr);</FONT>
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<P><FONT SIZE=2>My concern is about the ability to return error status. The failure may be due</FONT>
<BR><FONT SIZE=2>to lack of resources, in which case, returning NULL makes sense. However,</FONT>
<BR><FONT SIZE=2>some may fail because of bad parameters being passed in. This is mainly</FONT>
<BR><FONT SIZE=2>because these functions not only deal with memory allocation of the object,</FONT>
<BR><FONT SIZE=2>they also deal with initialization of the object and configuration of the</FONT>
<BR><FONT SIZE=2>HW.</FONT>
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<P><FONT SIZE=2>It's not so bad just to return NULL when the operation fails and drop</FONT>
<BR><FONT SIZE=2>the error code. But, even for the sake of debug and diagnostics, I'd </FONT>
<BR><FONT SIZE=2>consider allowing the propagation of a return code.</FONT>
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<P><FONT SIZE=2>-Dror</FONT>
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