| # apebs = # wlar, # buf1 = LEB_SIZE, wlar[vtblpnum2] = wl-entry(m1, used), wlar[vtblpnum1] = wl-entry(m0, free), apebs[vtblpnum2] = mkpeb(aehdr, avhdr0, buf0, m2, false), wlar0 = wlar, vtblpnum2 < # wlar, vtblpnum1 < # wlar, bflipset-cons(bflipset0, wlar), ubi-io-inv(apebs), ubi-io-peb-inv(mkpeb(aehdr, avhdr0, buf0, m2, false)), unique-sqns(apebs), valid-ebatbl(apebs, wlar, vols, n2), valid-eraseq(q), valid-eraseq(wlar, q), valid-eraseq(apebs, q), valid-global-sqn(apebs, n1), valid-vtbl(apebs, vols, wlar, n2), valid-wl(apebs, wlar), m1 + WL_THRESHOLD ≤ m0, ⌊err0⌋ ⊦ [q1 := q; apebs1 := apebs; if err0 = ESUCCESS then {ubi_erase_worker_helper#(vtblpnum2; wlar, apebs; err0); if err0 = ESUCCESS then q := q.butlast}] ( # apebs = # wlar ∧ unique-sqns(apebs) ∧ valid-global-sqn(apebs, n1) ∧ valid-wl(apebs, wlar) ∧ valid-eraseq(q) ∧ valid-eraseq(wlar, q) ∧ valid-eraseq(apebs, q) ∧ bflipset-cons(bflipset0, wlar) ∧ valid-ebatbl(apebs, wlar, vols, n2) ∧ valid-vtbl(apebs, vols, wlar, n2) ∧ ubi-io-inv(apebs) ∧ ( id(apebs, apebs1, mapped-pebs(vols)) ∧ q.lebrefs ⊆ q1.lebrefs ++ (VTBL_VOLID × VTBL_LNUM) ∨ (∃ v, m, n. v ∈ vols ∧ m < # vols[v] ∧ vols[v][m] ≠ unmapped ∧ vols = vols[v, vols[v][m, ⌜n⌝ ]] ∧ id(apebs, apebs1, mapped-pebs(vols) -- vols[v][m].pnum) ∧ apebs[n].data = apebs1[vols[v][m].pnum].data ∧ apebs[n].fill ≤ apebs1[vols[v][m].pnum].fill ∧ q.lebrefs ⊆ q1.lebrefs ++ (v × m))) → err0 = ESUCCESS → Δ wlar < Δ wlar0), VTBL_VOLID ∈ vols |
# buf1 = LEB_SIZE, # apebs = # wlar, apebs[vtblpnum2] = mkpeb(aehdr, avhdr0, buf0, m2, false), wlar[vtblpnum1] = wl-entry(m0, free), wlar[vtblpnum2] = wl-entry(m1, used), q1 = q, wlar0 = wlar, vtblpnum1 < # wlar, vtblpnum2 < # wlar, bflipset-cons(bflipset0, wlar), ubi-io-inv(apebs), ubi-io-peb-inv(mkpeb(aehdr, avhdr0, buf0, m2, false)), unique-sqns(apebs), valid-ebatbl(apebs, wlar, vols, n2), valid-eraseq(apebs, q), valid-eraseq(wlar, q), valid-eraseq(q), valid-global-sqn(apebs, n1), valid-vtbl(apebs, vols, wlar, n2), valid-wl(apebs, wlar), m1 + WL_THRESHOLD ≤ m0, ⌊err0⌋ ⊦ [apebs1 := apebs; if err0 = ESUCCESS then {ubi_erase_worker_helper#(vtblpnum2; wlar, apebs; err0); if err0 = ESUCCESS then q := q.butlast}] ( # apebs = # wlar ∧ unique-sqns(apebs) ∧ valid-global-sqn(apebs, n1) ∧ valid-wl(apebs, wlar) ∧ valid-eraseq(q) ∧ valid-eraseq(wlar, q) ∧ valid-eraseq(apebs, q) ∧ bflipset-cons(bflipset0, wlar) ∧ valid-ebatbl(apebs, wlar, vols, n2) ∧ valid-vtbl(apebs, vols, wlar, n2) ∧ ubi-io-inv(apebs) ∧ ( id(apebs, apebs1, mapped-pebs(vols)) ∧ q.lebrefs ⊆ q1.lebrefs ++ (VTBL_VOLID × VTBL_LNUM) ∨ (∃ v, m, n. v ∈ vols ∧ m < # vols[v] ∧ vols[v][m] ≠ unmapped ∧ vols = vols[v, vols[v][m, ⌜n⌝ ]] ∧ id(apebs, apebs1, mapped-pebs(vols) -- vols[v][m].pnum) ∧ apebs[n].data = apebs1[vols[v][m].pnum].data ∧ apebs[n].fill ≤ apebs1[vols[v][m].pnum].fill ∧ q.lebrefs ⊆ q1.lebrefs ++ (v × m))) → err0 = ESUCCESS → Δ wlar < Δ wlar0), VTBL_VOLID ∈ vols