Hi Kirill, On Wed, Jan 29, 2020 at 11:46 AM Kirill A. Shutemov <kirill@xxxxxxxxxxxxx> wrote: > And based on the use case you probably don't really need 'fixed' > semantics all the time. The user should be fine with moving the mapping > *somewhere*, not neccessary to the given address This is true and and it simplifies things a bit as for the outlined use cases the user would not be required to mmap the destination before hand. Part of the reason I chose to require MREMAP_FIXED was because mremap need not move the mapping if it can shrink/grow in place and it seemed a bit awkward to have "MUSTMOVE" behavior without MAP_FIXED. I'll make this change to drop the requirement on MREMAP_FIXED in my next patch. > BTW, name of the flag is confusing. My initial reaction was that it is > variant of MREMAP_FIXED that does't anything at the target address. > Like MAP_FIXED vs. MAP_FIXED_NOREPLACE. > > Any better options for the flag name? (I have none) I see your point. Perhaps MREMAP_MOVEPAGES or MREMAP_KEEP_SOURCE? I struggle to come up with a single name that encapsulates this behavior but I'll try to think of other ideas before I mail the next patch. Given that we will drop the requirement on MREMAP_FIXED, perhaps MOVEPAGES is the better option as it captures that the mapping WILL be moved? Thanks again for taking the time to look at this. Best, Brian
