#!/usr/bin/env python3
# wall2_resolver7.py - resolver6 + release-window injection + live-first ordering.
# Fixes the resolver6 zero-page overwrite: candidates are injected good-first
# (live_nz>0) and zero pages last, so the readable mapping wins by order if the
# service keeps the newest write.
# New: the GR init release windows (0x4b16000 size 0x1000 from the record page,
# and any {VA,0x1000} record alongside) are injected from the size-0x1000
# memdescs of the same page.
import subprocess, struct, time, sys, os

RAM = "/dev/shm/vgpu-guest-ram"
PARAM = "/sys/module/vgsp/parameters/sema_map_add"
LOG = "/tmp/opencode/wall2_resolver7.log"
WATCH_S = int(os.environ.get("W2_WATCH", "420"))
PAIRS = [(0x4480000, 0x44a0000), (0x4ca0000, 0x4cc0000)]
REL_WINS = [0x4b16000]

logf = open(LOG, "a", buffering=1)
def log(*a):
    s = " ".join(str(x) for x in a)
    print(s, flush=True)
    logf.write("[%s] %s\n" % (time.strftime("%H:%M:%S"), s))

img = open(RAM, "rb", buffering=0)
def off2gpa(off): return off if off < 0x80000000 else 0x100000000+(off-0x80000000)
def gpa2off(pa):
    if pa < 0x80000000: return pa
    if pa < 0x180000000: return 0x80000000 + (pa - 0x100000000)
    return None
def rd(pa, n):
    off = gpa2off(pa)
    if off is None: return None
    img.seek(off); return img.read(n)

def inject(va, pa, ln=0x1000, ap=1):
    cmd = "echo 0x%x,0x%x,0x%x,%d > %s" % (va, pa, ln, ap, PARAM)
    r = subprocess.run(["sudo", "sh", "-c", cmd], capture_output=True, text=True)
    if r.returncode == 0:
        log("INJECT va=0x%x -> pa=0x%x" % (va, pa))
        return True
    log("inject FAIL rc=%d %s" % (r.returncode, r.stderr.strip()))
    return False

def find_qpair(a, b):
    img.seek(0, 2); fsz = img.tell()
    pat = struct.pack("<QQ", a, b)
    out = []
    CH = 64 << 20
    pos = 0
    while pos < fsz:
        img.seek(pos); d = img.read(min(CH, fsz - pos))
        st = 0
        while True:
            i = d.find(pat, st)
            if i < 0: break
            st = i + 1
            out.append(off2gpa(pos + i) & ~0xfff)
        pos += CH
    return out

def collect(page):
    d = rd(page, 0x1000)
    if not d: return None
    descs = []
    wins = []
    for o in range(0, 0x1000 - 24, 8):
        sz, fl = struct.unpack_from("<QQ", d, o)
        pa = struct.unpack_from("<Q", d, o + 16)[0]
        if fl == 0x03008000 and 0x1000 <= sz <= 0x400000 and \
           0x100000000 <= pa < 0x180000000:
            descs.append((o, sz, pa))
        va2 = sz
        if 0x4000000 <= va2 < 0x100000000 and (va2 & 0xfff) == 0:
            sz2 = fl
            if 0x1000 <= sz2 <= 0x1000000 and (sz2 & 0xfff) == 0:
                wins.append((va2, sz2))
    return descs, wins

def main():
    log("=== resolver7 start (watch=%ds) ===" % WATCH_S)
    injected = set()
    deadline = time.time() + WATCH_S
    while time.time() < deadline:
        pages = set()
        for (pva, rva) in PAIRS:
            try:
                pages |= set(find_qpair(pva, 0x20000)) & set(find_qpair(rva, 0x40000))
            except Exception as e:
                log("scan error:", e)
        for page in sorted(pages):
            got = collect(page)
            if not got: continue
            descs, wins = got
            # push windows: inject live-first (nz>0 first, zeros last)
            for (pva, _rva) in PAIRS:
                cands = [(o, sz, pa) for (o, sz, pa) in descs if sz == 0x20000]
                order = []
                for (o, sz, pa) in cands:
                    pd = rd(pa, 0x40)
                    nz = sum(1 for b in pd if b) if pd else -1
                    log("pair=0x%x page=0x%x desc@0x%x pa=0x%x live_nz=%d" % (pva, page, o, pa, nz))
                    order.append((nz, o, pa))
                order.sort(key=lambda t: t[0])  # zeros first, live last
                for (nz, o, pa) in order:
                    key = (pva, page, o)
                    if key in injected: continue
                    if inject(pva, pa):
                        injected.add(key)
            # release windows: any {VA, 0x1000} record on the page -> size-0x1000 descs
            for (va, sz) in wins:
                if va not in REL_WINS and not (0x4b00000 <= va <= 0x4b20000):
                    continue
                for (o, dsz, pa) in descs:
                    if dsz != sz:
                        continue
                    key = (va, page, o)
                    if key in injected: continue
                    if inject(va, pa):
                        injected.add(key)
        time.sleep(1)
    log("=== resolver7 done: %d injection(s) ===" % len(injected))
    return 0

if __name__ == "__main__":
    sys.exit(main())