Add blkptr command to sdb.

Author: PaulZ-98

sdb/commands/zfs/blkptr.py

@@ -0,0 +1,363 @@
+#
+# Copyright 2019 Delphix
+# Copyright 2021 Datto, Inc.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+# pylint: disable=missing-docstring
+
+from typing import Iterable
+
+import drgn
+import sdb
+from sdb.commands.zfs.internal import BF64_GET, BF64_GET_SB
+
+
+class BpInfo:
+    """
+    Store attributes of the block pointer and
+    get formatted representations of them.
+    """
+
+    # pylint: disable=too-many-instance-attributes
+
+    ndvas = 0
+    level = 0
+    ot_type = 0
+    compress = 0
+    birth = 0
+    cksum = 0
+    byte_order = 0
+    gang = 0
+    dedup = 0
+    copies = ""
+    pbirth = 0
+    lsize = ""
+    psize = ""
+    crypt = ""
+    c0 = ""
+    c1 = ""
+    c2 = ""
+    c3 = ""
+
+    def set_ndvas(self, nd: int) -> None:
+        self.ndvas = nd
+
+    def set_initial_props(self, bp: drgn.Object) -> None:
+        self.level = BF64_GET(bp.blk_prop, 56, 5)
+        self.ot_type = int(BF64_GET(bp.blk_prop, 48, 8))
+        self.compress = BF64_GET(bp.blk_prop, 32, 7)
+        self.lsize = format(Blkptr.bp_get_lsize(bp), 'x')
+        self.psize = format(Blkptr.bp_get_psize(bp), 'x')
+        self.birth = int(bp.blk_birth)
+        self.cksum = BF64_GET(bp.blk_prop, 40, 8)
+        self.byte_order = BF64_GET(bp.blk_prop, 63, 1)
+        self.crypt = Blkptr.bp_get_crypt(bp, self.ot_type, self.level)
+        self.gang = (0 if Blkptr.bp_is_embedded(bp) else BF64_GET(
+            bp.blk_dva[0].dva_word[1], 63, 1))
+        self.dedup = BF64_GET(bp.blk_prop, 62, 1)
+        self.copies = Blkptr.copyname[self.ndvas]
+        self.pbirth = Blkptr.bp_physical_birth(bp)
+        self.c0 = '%x' % bp.blk_cksum.zc_word[0]
+        self.c1 = '%x' % bp.blk_cksum.zc_word[1]
+        self.c2 = '%x' % bp.blk_cksum.zc_word[2]
+        self.c3 = '%x' % bp.blk_cksum.zc_word[3]
+
+    def get_compstr(self) -> str:
+        comps = sdb.get_object("zio_compress_table")
+        return str(comps[self.compress].ci_name.string_().decode("utf-8"))
+
+    def get_ot_name(self) -> str:
+        if self.ot_type & Blkptr.DMU_OT_NEWTYPE:
+            if self.ot_type & Blkptr.DMU_OT_BYTESWAP_MASK > 9:
+                print(str(self.ot_type & Blkptr.DMU_OT_BYTESWAP_MASK))
+                return str(self.ot_type & Blkptr.DMU_OT_BYTESWAP_MASK)
+            bswaps = sdb.get_object("dmu_ot_byteswap")
+            swap_entry = bswaps[self.ot_type & Blkptr.DMU_OT_BYTESWAP_MASK]
+            byte_swap = swap_entry.ob_name.string_().decode("utf-8")
+            meta = "metadata" if self.ot_type & Blkptr.DMU_OT_METADATA else "data"
+            return "bswap %s %s" % (meta, byte_swap)
+        return str(
+            sdb.get_object("dmu_ot")[self.ot_type].ot_name.string_().decode(
+                "utf-8"))
+
+    def get_fill(self, bp: drgn.Object) -> int:
+        if Blkptr.bp_is_encrypted(bp, self.ot_type, self.level):
+            return BF64_GET(bp.blk_fill, 0, 32)
+        if Blkptr.bp_is_embedded(bp):
+            return 1
+        return int(bp.blk_fill)
+
+    def get_cksum_string(self) -> str:
+        cksums = sdb.get_object("zio_checksum_table")
+        return str(cksums[self.cksum].ci_name.string_().decode("utf-8"))
+
+    def get_endian(self) -> str:
+        return "BE" if self.byte_order == 0 else "LE"
+
+    def get_gang(self) -> str:
+        return "gang" if self.gang else "contiguous"
+
+    def get_dedup(self) -> str:
+        return "dedup" if self.dedup else "unique"
+
+
+class Blkptr(sdb.PrettyPrinter):
+    """
+    DESCRIPTION
+
+        Pretty-print zfs block pointers.
+
+    EXAMPLES
+
+        sdb> dbuf | head 1 | member db_blkptr | blkptr
+        DVA[0]=<0:2cefd5e00:20000> [L0 ZFS plain file] fletcher4 uncompressed unencrypted LE
+        contiguous unique single 20000L/20000P birth=1624L/1624P fill=1 cksum=3feb86d3fa14:
+        ff98411222361a1:7cd8eb3816d141e1:2d65ae38a67197c7
+
+        sdb> echo 0xffffa0889343c680 | blkptr
+        DVA[0]=<0:41e90000:30000> [L0 ZFS plain file] fletcher4 uncompressed unencrypted LE
+        contiguous unique single 20000L/20000P birth=10L/10P fill=1 cksum=3ffba121eb4d:
+        ffd4345f8d679e2:efa124922f72ec66:34642a9a05fbafef
+    """
+
+    BP_EMBEDDED_TYPE_DATA = 0
+    BP_EMBEDDED_TYPE_REDACTED = 2
+
+    SPA_MINBLOCKSHIFT = 9
+    SPA_MAXBLOCKSHIFT = 24
+    SPA_MAXBLOCKSIZE = 1 << SPA_MAXBLOCKSHIFT
+    SPA_ASIZEBITS = 24
+    SPA_VDEVBITS = 24
+    SPA_LSIZEBITS = 16
+    SPA_PSIZEBITS = 16
+
+    TRUE = 1
+    FALSE = 0
+
+    DMU_OT_NEWTYPE = 128
+    DMU_OT_ENCRYPTED = 32
+    DMU_OT_METADATA = 0x40
+    DMU_OT_BYTESWAP_MASK = 0x1f
+
+    copyname = ['zero', 'single', 'double', 'triple']
+
+    @staticmethod
+    def __bp_is_authenticated(bp: drgn.Object, ot: int, level: int) -> int:
+        return (Blkptr.bp_uses_crypt(bp) and level > 0 and
+                not Blkptr.dmu_ot_is_encrypted(ot))
+
+    @staticmethod
+    def __bp_has_indirect_mac_checksum(bp: drgn.Object, level: int) -> int:
+        return Blkptr.bp_uses_crypt(bp) and level > 0
+
+    @staticmethod
+    def __dmu_ot_is_valid(bp: drgn.Object) -> int:
+        ot = BF64_GET(bp.blk_prop, 48, 8)
+        if ot & Blkptr.DMU_OT_NEWTYPE:
+            return (ot & Blkptr.DMU_OT_BYTESWAP_MASK < len(
+                sdb.get_object("dmu_ot_byteswap")))
+        return ot < len(sdb.get_object("dmu_ot"))
+
+    @staticmethod
+    def dmu_ot_is_encrypted(ot: int) -> int:
+        if ot & Blkptr.DMU_OT_NEWTYPE:
+            return ot & Blkptr.DMU_OT_ENCRYPTED
+        return int(sdb.get_object("dmu_ot")[ot].ot_encrypt)
+
+    @staticmethod
+    def bp_is_embedded(bp: drgn.Object) -> int:
+        return BF64_GET(bp.blk_prop, 39, 1)
+
+    @staticmethod
+    def bp_is_redacted(bp: drgn.Object) -> int:
+        return (Blkptr.bp_is_embedded(bp) and BF64_GET(bp.blk_prop, 40, 8)
+                == Blkptr.BP_EMBEDDED_TYPE_REDACTED)
+
+    @staticmethod
+    def bp_uses_crypt(bp: drgn.Object) -> int:
+        return BF64_GET(bp.blk_prop, 61, 1)
+
+    @staticmethod
+    def bp_is_encrypted(bp: drgn.Object, ot: int, level: int) -> int:
+        return (Blkptr.bp_uses_crypt(bp) and level <= 0 and
+                Blkptr.dmu_ot_is_encrypted(ot))
+
+    @staticmethod
+    def bp_get_crypt(bp: drgn.Object, ot: int, level: int) -> str:
+        if Blkptr.bp_is_encrypted(bp, ot, level):
+            return "encrypted"
+        if Blkptr.__bp_is_authenticated(bp, ot, level):
+            return "authenticated"
+        if Blkptr.__bp_has_indirect_mac_checksum(bp, level):
+            return "indirect-MAC"
+        return "unencrypted"
+
+    @staticmethod
+    def dva_is_empty(bp: drgn.Object) -> int:
+        return int(bp.blk_dva[0].dva_word[0] == 0 and
+                   bp.blk_dva[0].dva_word[1] == 0)
+
+    @staticmethod
+    def dva_get_offset(bp: drgn.Object, which_dva: int) -> int:
+        return BF64_GET_SB(bp.blk_dva[which_dva].dva_word[1], 0, 63,
+                           Blkptr.SPA_MINBLOCKSHIFT, 0)
+
+    @staticmethod
+    def dva_get_vdev(bp: drgn.Object, which_dva: int) -> int:
+        return BF64_GET(bp.blk_dva[which_dva].dva_word[0], 32,
+                        Blkptr.SPA_VDEVBITS)
+
+    @staticmethod
+    def __bp_is_hole(bp: drgn.Object) -> int:
+        return Blkptr.bp_is_embedded(bp) != Blkptr.TRUE and Blkptr.dva_is_empty(
+            bp)
+
+    @staticmethod
+    def dva_get_asize(bp: drgn.Object, which_dva: int) -> int:
+        if Blkptr.bp_is_embedded(bp):
+            return 0
+        return BF64_GET_SB(bp.blk_dva[which_dva].dva_word[0], 0,
+                           Blkptr.SPA_ASIZEBITS, Blkptr.SPA_MINBLOCKSHIFT, 0)
+
+    @staticmethod
+    def bp_get_ndvas(bp: drgn.Object) -> int:
+        ndvas = 0
+        for x in range(0, 3):
+            ndvas += Blkptr.dva_get_asize(bp, x) != 0
+        return ndvas
+
+    @staticmethod
+    def bpe_get_lsize(bp: drgn.Object) -> int:
+        return BF64_GET_SB(bp.blk_prop, 0, 25, 0, 1)
+
+    @staticmethod
+    def bp_get_lsize(bp: drgn.Object) -> int:
+        if Blkptr.bp_is_embedded(bp):
+            if BF64_GET(bp.blk_prop, 40, 8) == Blkptr.BP_EMBEDDED_TYPE_DATA:
+                return Blkptr.bpe_get_lsize(bp)
+            return 0
+        return BF64_GET_SB(bp.blk_prop, 0, Blkptr.SPA_LSIZEBITS,
+                           Blkptr.SPA_MINBLOCKSHIFT, 1)
+
+    @staticmethod
+    def bp_get_psize(bp: drgn.Object) -> int:
+        if Blkptr.bp_is_embedded(bp):
+            return 0
+        return BF64_GET_SB(bp.blk_prop, 16, Blkptr.SPA_PSIZEBITS,
+                           Blkptr.SPA_MINBLOCKSHIFT, 1)
+
+    @staticmethod
+    def bp_physical_birth(bp: drgn.Object) -> int:
+        if Blkptr.bp_is_embedded(bp):
+            phys = 0
+        else:
+            phys = bp.blk_phys_birth if bp.blk_phys_birth != 0 else bp.blk_birth
+        return int(phys)
+
+    @staticmethod
+    def bp_get_checksum(bp: drgn.Object) -> int:
+        if Blkptr.bp_is_embedded(bp):
+            return 2  # ZIO_CHECKSUM_OFF
+        return BF64_GET(bp.blk_prop, 40, 8)
+
+    @staticmethod
+    def bp_validate(bp: drgn.Object) -> int:
+        errors = 0
+        addr = hex(bp)
+        if not Blkptr.__dmu_ot_is_valid(bp):
+            tp = BF64_GET(bp.blk_prop, 48, 8)
+            print(f"blkptr at {addr} has invalid TYPE {tp}")
+            errors += 1
+        ck = Blkptr.bp_get_checksum(bp)
+        if ck >= len(sdb.get_object("zio_checksum_table")) or ck <= 1:
+            print(f"blkptr at {addr} has invalid CHECKSUM {ck}")
+            errors += 1
+        comp = BF64_GET(bp.blk_prop, 32, 7)
+        if comp >= len(sdb.get_object("zio_compress_table")) or comp <= 1:
+            print(f"blkptr at {addr} has invalid COMPRESS {comp}")
+            errors += 1
+        lsz = Blkptr.bp_get_lsize(bp)
+        psz = Blkptr.bp_get_psize(bp)
+        if lsz > Blkptr.SPA_MAXBLOCKSIZE:
+            print(f"blkptr at {addr} has invalid LSIZE {lsz}")
+            errors += 1
+        if psz > Blkptr.SPA_MAXBLOCKSIZE:
+            print(f"blkptr at {addr} has invalid PSIZE {psz}")
+            errors += 1
+        if Blkptr.bp_is_embedded(bp):
+            etype = BF64_GET(bp.blk_prop, 40, 8)
+            if etype >= 3:
+                print(f"blkptr at {addr} has invalid ETYPE {etype}")
+                errors += 1
+        return errors
+
+    names = ["blkptr"]
+    input_type = "blkptr_t *"
+
+    def pretty_print(self, objs: Iterable[drgn.Object]) -> None:
+        for bp in objs:
+            if bp is None:
+                print("<NULL>")
+                continue
+            if not Blkptr.__bp_is_hole(bp) and Blkptr.bp_validate(bp) != 0:
+                continue
+            bpi = BpInfo()
+            if Blkptr.bp_is_embedded(bp) != 0:
+                bpi.set_ndvas(0)
+            else:
+                bpi.set_ndvas(Blkptr.bp_get_ndvas(bp))
+            for i in range(0, bpi.ndvas):
+                vdev = Blkptr.dva_get_vdev(bp, i)
+                offset = format(Blkptr.dva_get_offset(bp, i), 'x')
+                asize = format(Blkptr.dva_get_asize(bp, i), 'x')
+                print(f"DVA[{i}]=<{vdev}:{offset}:{asize}> ", end='')
+
+            bpi.set_initial_props(bp)
+
+            if Blkptr.bp_is_embedded(bp) != 0:
+                etype = BF64_GET(bp.blk_prop, 40, 8)
+                lsize = format(BF64_GET_SB(bp.blk_prop, 0, 25, 0, 1), 'x')
+                psize = format(BF64_GET_SB(bp.blk_prop, 25, 7, 0, 1), 'x')
+                print(
+                    f"EMBEDDED [L{bpi.level} {bpi.get_ot_name()}] et={etype} ",
+                    end='')
+                print(f"{bpi.get_compstr()} size=", end='')
+                print(f"{lsize}L/{psize}P birth={bpi.birth}L")
+                continue
+            if Blkptr.__bp_is_hole(bp):
+                print(
+                    f"HOLE [L{bpi.level} {bpi.get_ot_name()}] size={bpi.lsize}L ",
+                    end='')
+                print(f"birth={bpi.birth}L")
+                continue
+            if Blkptr.bp_is_redacted(bp):
+                print(
+                    f"REDACTED [L{bpi.level} {bpi.get_ot_name()}] size={bpi.lsize}L ",
+                    end='')
+                print(f"birth={bpi.birth}L")
+                continue
+
+            print(
+                f"[L{bpi.level} {bpi.get_ot_name()}] {bpi.get_cksum_string()}",
+                end='')
+            print(
+                f" {bpi.get_compstr()} {bpi.crypt} {bpi.get_endian()} {bpi.get_gang()}",
+                end='')
+            print(f" {bpi.get_dedup()} {bpi.copies} {bpi.lsize}L/{bpi.psize}P ",
+                  end='')
+            print(f"birth={bpi.birth}L/{bpi.pbirth}P", end='')
+            print(
+                f" fill={bpi.get_fill(bp)} cksum={bpi.c0}:{bpi.c1}:{bpi.c2}:{bpi.c3}"
+            )

sdb/commands/zfs/internal/__init__.py

@@ -51,6 +51,10 @@ def BF64_GET(x: drgn.Object, low: int, length: int) -> int:
     return BF64_DECODE(x, low, length)
 
 
+def BF64_GET_SB(x: int, low: int, length: int, shift: int, bias: int) -> int:
+    return (BF64_GET(x, low, length) + bias) << shift
+
+
 def WEIGHT_IS_SPACEBASED(weight: int) -> bool:
     return weight == 0 or (BF64_GET(weight, 60, 1) != 0)
 

tests/integration/data/regression_output/linux/slabs | filter 'obj.name == "dnode_t"' |walk | head 6056 | tail 1| cast dnode_t * | deref |member dn_phys |member dn_blkptr[0] |blkptr

@@ -0,0 +1,2 @@
+blkptr at 0xffffa088ce68c040 has invalid CHECKSUM 0
+blkptr at 0xffffa088ce68c040 has invalid COMPRESS 0

tests/integration/data/regression_output/linux/slabs | filter 'obj.name == "dnode_t"' |walk | tail 8 | head 1 | cast dnode_t * | deref |member dn_phys |member dn_blkptr[0] |blkptr

@@ -0,0 +1 @@
+HOLE [L0 unallocated] size=200L birth=0L

tests/integration/data/regression_output/zfs/dbuf | head 1 | member db_blkptr | blkptr

@@ -0,0 +1 @@
+DVA[0]=<0:2cefd5e00:20000> [L0 ZFS plain file] fletcher4 uncompressed unencrypted LE contiguous unique single 20000L/20000P birth=1624L/1624P fill=1 cksum=3feb86d3fa14:ff98411222361a1:7cd8eb3816d141e1:2d65ae38a67197c7

tests/integration/data/regression_output/zfs/spa | head 1 | deref |member spa_uberblock | member ub_rootbp | blkptr

@@ -0,0 +1 @@
+DVA[0]=<0:80001e00:200> DVA[1]=<0:a0001e00:200> DVA[2]=<0:10000da00:200> [L0 DMU objset] fletcher4 lz4 unencrypted LE contiguous unique triple 1000L/200P birth=609L/609P fill=67 cksum=98a43f544:3eab35f140c:d164e4328324:1da8f37ef09087

tests/integration/test_linux_generic.py

@@ -68,6 +68,8 @@
     "slabs | pp",
     "slabs -s util | slabs",
     "slabs | head 2 | slabs",
+    'slabs | filter \'obj.name == "dnode_t"\' |walk | tail 8 | head 1 | cast dnode_t * | deref |member dn_phys |member dn_blkptr[0] |blkptr',
+    'slabs | filter \'obj.name == "dnode_t"\' |walk | head 6056 | tail 1| cast dnode_t * | deref |member dn_phys |member dn_blkptr[0] |blkptr',
 
     # slub
     'slabs | filter \'obj.name == "zio_cache"\' | slub_cache',