#!/usr/bin/env python3
# r673: find the push page. Patterns: ring entry raw qwords, the sem VA, and
# method-stream signatures. Dump contexts.
import numpy as np, struct, os, time

RAM="/dev/shm/vgpu-guest-ram"
img=open(RAM,"rb"); fsz=os.path.getsize(RAM)
def gpa2off(pa):
    if pa < 0x80000000: return pa
    if pa < 0x180000000: return 0x80000000+(pa-0x100000000)
    return None
def off2gpa(off):
    return off if off < 0x80000000 else 0x100000000+(off-0x80000000)
def rd(pa,n):
    off=gpa2off(pa)
    if off is None or off+n>fsz: return None
    img.seek(off); return img.read(n)

pats=[
 ("entry0raw", 0x0005980004500000),
 ("entry1raw", 0x0000040004500598),
 ("entry2raw", 0x0003d0000450059c),
 ("sem_va",    0x4500598),
 ("sem_va2",   0x450059c),
 ("m20038090", 0x20038090),
 ("push_va",   0x4500000),
]
CH=64<<20
for name,pat in pats:
    hits=[]
    t0=time.time()
    for pos in range(0,fsz,CH):
        img.seek(pos); d=img.read(min(CH,fsz-pos))
        n=len(d)//8
        a=np.frombuffer(d[:n*8],dtype=np.uint64)
        idx=np.nonzero(a==np.uint64(pat))[0]
        for i in idx: hits.append(pos+int(i)*8)
    print("== %s pat=0x%x hits=%d (%.1fs)" % (name,pat,len(hits),time.time()-t0))
    for off in hits[:12]:
        gpa=off2gpa(off); page=gpa&~0xfff
        d=rd(page,0x1000)
        ro=gpa-page
        s=max(0,ro-24); e=min(0x1000,ro+40)
        print("   gpa=0x%x page=0x%x off=0x%x ctx=%s" % (gpa,page,ro,d[s:e].hex() if d else "?"))
    if len(hits)>12: print("   ... %d more" % (len(hits)-12))