| # buf1 = 2 * NODE_HEADER_SIZE + ind.alignedsize, # lpt1 = # avol, # lpt0 = # avol, isbuf ↔ isbuf1, lpt1[n] = mklp(m1, # buf0, LP_INDEX_NODES, m2), avol[n] = mapped(buf0), adr = adr0, bleb = buffered(n), buf = buf1, ¬ isbuf1, keyset(gch) = gc-heap(lpt1, log0), log = log0, lpt = lpt0, n0 = # buf1, n < # avol, abs-node(buf1, ind), awbuf-inv(avol, buffered(n)), bin-heap-inv(gch, lpt1), buf-ro-rw-mode(false, buffered(n), lpt1, avol), bufs-log-only(buffered(n), log0, lpt1), freelist-cons(lpt1, freelist), log-group-block(log0, lpt1), lpt-free-unref(lpt1), lpt-free-unref(lpt0), lpt-leb-size(lpt1), lpt-leb-size(lpt0), lpt-ram-flash(lpt1, lpt0, log0), # buf0 + # buf1 ≤ LEB_SIZE, bleb ≠ nobuffer → avol[bleb.leb].mapped? ∧ bleb.leb < # avol ∧ bleb.isbuf? ⊦ [abort] ( awbuf-inv(avol, buffered(n)) ∧ # lpt0 = # avol → ⟪if err = ESUCCESS then {adr := @(buffered(n).leb, lpt1[buffered(n).leb].size, # buf1); lpt1[buffered(n).leb] := mklp (lpt1[buffered(n).leb].ref-size, lpt1[buffered(n).leb].size + # buf1, lpt1[buffered(n).leb].flags, lpt1[buffered(n).leb].gcheapidx)} else lpt1[buffered(n).leb] := mklp(lpt1[buffered(n).leb].ref-size, LEB_SIZE, lpt1[buffered(n).leb].flags, lpt1[buffered(n).leb].gcheapidx)⟫ ( lpt-free-unref(lpt1) ∧ freelist-cons(lpt1, freelist) ∧ bin-heap-inv(gch, lpt1) ∧ keyset(gch) = gc-heap(lpt1, log0) ∧ bufs-log-only(buffered(n), log0, lpt1) ∧ # lpt1 = # avol ∧ log-group-block(log0, lpt1) ∧ buf-ro-rw-mode(isbuf, buffered(n), lpt1, avol) ∧ lpt-leb-size(lpt1) ∧ lpt-ram-flash(lpt1, lpt0, log0))), bleb ≠ nobuffer ∧ # avol[bleb.leb].data + n0 ≤ LEB_SIZE ∧ n0 ≤ # buf |