1 // SPDX-License-Identifier: GPL-2.0
3 * Copyright (c) 2000-2006 Silicon Graphics, Inc.
8 #include "xfs_shared.h"
9 #include "xfs_format.h"
10 #include "xfs_log_format.h"
11 #include "xfs_trans_resv.h"
12 #include "xfs_mount.h"
14 #include "xfs_inode.h"
15 #include "xfs_errortag.h"
16 #include "xfs_error.h"
17 #include "xfs_icache.h"
18 #include "xfs_trans.h"
19 #include "xfs_ialloc.h"
22 #include <linux/iversion.h>
25 * If we are doing readahead on an inode buffer, we might be in log recovery
26 * reading an inode allocation buffer that hasn't yet been replayed, and hence
27 * has not had the inode cores stamped into it. Hence for readahead, the buffer
28 * may be potentially invalid.
30 * If the readahead buffer is invalid, we need to mark it with an error and
31 * clear the DONE status of the buffer so that a followup read will re-read it
32 * from disk. We don't report the error otherwise to avoid warnings during log
33 * recovery and we don't get unnecessary panics on debug kernels. We use EIO here
34 * because all we want to do is say readahead failed; there is no-one to report
35 * the error to, so this will distinguish it from a non-ra verifier failure.
36 * Changes to this readahead error behaviour also need to be reflected in
37 * xfs_dquot_buf_readahead_verify().
44 struct xfs_mount *mp = bp->b_mount;
49 * Validate the magic number and version of every inode in the buffer
51 ni = XFS_BB_TO_FSB(mp, bp->b_length) * mp->m_sb.sb_inopblock;
52 for (i = 0; i < ni; i++) {
53 struct xfs_dinode *dip;
54 xfs_agino_t unlinked_ino;
57 dip = xfs_buf_offset(bp, (i << mp->m_sb.sb_inodelog));
58 unlinked_ino = be32_to_cpu(dip->di_next_unlinked);
59 di_ok = xfs_verify_magic16(bp, dip->di_magic) &&
60 xfs_dinode_good_version(mp, dip->di_version) &&
61 xfs_verify_agino_or_null(bp->b_pag, unlinked_ino);
62 if (unlikely(XFS_TEST_ERROR(!di_ok, mp,
63 XFS_ERRTAG_ITOBP_INOTOBP))) {
65 bp->b_flags &= ~XBF_DONE;
66 xfs_buf_ioerror(bp, -EIO);
72 "bad inode magic/vsn daddr %lld #%d (magic=%x)",
73 (unsigned long long)xfs_buf_daddr(bp), i,
74 be16_to_cpu(dip->di_magic));
76 xfs_buf_verifier_error(bp, -EFSCORRUPTED,
77 __func__, dip, sizeof(*dip),
86 xfs_inode_buf_read_verify(
89 xfs_inode_buf_verify(bp, false);
93 xfs_inode_buf_readahead_verify(
96 xfs_inode_buf_verify(bp, true);
100 xfs_inode_buf_write_verify(
103 xfs_inode_buf_verify(bp, false);
106 const struct xfs_buf_ops xfs_inode_buf_ops = {
108 .magic16 = { cpu_to_be16(XFS_DINODE_MAGIC),
109 cpu_to_be16(XFS_DINODE_MAGIC) },
110 .verify_read = xfs_inode_buf_read_verify,
111 .verify_write = xfs_inode_buf_write_verify,
114 const struct xfs_buf_ops xfs_inode_buf_ra_ops = {
115 .name = "xfs_inode_ra",
116 .magic16 = { cpu_to_be16(XFS_DINODE_MAGIC),
117 cpu_to_be16(XFS_DINODE_MAGIC) },
118 .verify_read = xfs_inode_buf_readahead_verify,
119 .verify_write = xfs_inode_buf_write_verify,
124 * This routine is called to map an inode to the buffer containing the on-disk
125 * version of the inode. It returns a pointer to the buffer containing the
126 * on-disk inode in the bpp parameter.
130 struct xfs_mount *mp,
131 struct xfs_trans *tp,
132 struct xfs_imap *imap,
133 struct xfs_buf **bpp)
135 return xfs_trans_read_buf(mp, tp, mp->m_ddev_targp, imap->im_blkno,
136 imap->im_len, XBF_UNMAPPED, bpp,
140 static inline struct timespec64 xfs_inode_decode_bigtime(uint64_t ts)
142 struct timespec64 tv;
145 tv.tv_sec = xfs_bigtime_to_unix(div_u64_rem(ts, NSEC_PER_SEC, &n));
151 /* Convert an ondisk timestamp to an incore timestamp. */
153 xfs_inode_from_disk_ts(
154 struct xfs_dinode *dip,
155 const xfs_timestamp_t ts)
157 struct timespec64 tv;
158 struct xfs_legacy_timestamp *lts;
160 if (xfs_dinode_has_bigtime(dip))
161 return xfs_inode_decode_bigtime(be64_to_cpu(ts));
163 lts = (struct xfs_legacy_timestamp *)&ts;
164 tv.tv_sec = (int)be32_to_cpu(lts->t_sec);
165 tv.tv_nsec = (int)be32_to_cpu(lts->t_nsec);
172 struct xfs_inode *ip,
173 struct xfs_dinode *from)
175 struct inode *inode = VFS_I(ip);
179 ASSERT(ip->i_cowfp == NULL);
181 fa = xfs_dinode_verify(ip->i_mount, ip->i_ino, from);
183 xfs_inode_verifier_error(ip, -EFSCORRUPTED, "dinode", from,
185 return -EFSCORRUPTED;
189 * First get the permanent information that is needed to allocate an
190 * inode. If the inode is unused, mode is zero and we shouldn't mess
191 * with the uninitialized part of it.
193 if (!xfs_has_v3inodes(ip->i_mount))
194 ip->i_flushiter = be16_to_cpu(from->di_flushiter);
195 inode->i_generation = be32_to_cpu(from->di_gen);
196 inode->i_mode = be16_to_cpu(from->di_mode);
201 * Convert v1 inodes immediately to v2 inode format as this is the
202 * minimum inode version format we support in the rest of the code.
203 * They will also be unconditionally written back to disk as v2 inodes.
205 if (unlikely(from->di_version == 1)) {
206 set_nlink(inode, be16_to_cpu(from->di_onlink));
209 set_nlink(inode, be32_to_cpu(from->di_nlink));
210 ip->i_projid = (prid_t)be16_to_cpu(from->di_projid_hi) << 16 |
211 be16_to_cpu(from->di_projid_lo);
214 i_uid_write(inode, be32_to_cpu(from->di_uid));
215 i_gid_write(inode, be32_to_cpu(from->di_gid));
218 * Time is signed, so need to convert to signed 32 bit before
219 * storing in inode timestamp which may be 64 bit. Otherwise
220 * a time before epoch is converted to a time long after epoch
223 inode_set_atime_to_ts(inode,
224 xfs_inode_from_disk_ts(from, from->di_atime));
225 inode_set_mtime_to_ts(inode,
226 xfs_inode_from_disk_ts(from, from->di_mtime));
227 inode_set_ctime_to_ts(inode,
228 xfs_inode_from_disk_ts(from, from->di_ctime));
230 ip->i_disk_size = be64_to_cpu(from->di_size);
231 ip->i_nblocks = be64_to_cpu(from->di_nblocks);
232 ip->i_extsize = be32_to_cpu(from->di_extsize);
233 ip->i_forkoff = from->di_forkoff;
234 ip->i_diflags = be16_to_cpu(from->di_flags);
235 ip->i_next_unlinked = be32_to_cpu(from->di_next_unlinked);
237 if (from->di_dmevmask || from->di_dmstate)
238 xfs_iflags_set(ip, XFS_IPRESERVE_DM_FIELDS);
240 if (xfs_has_v3inodes(ip->i_mount)) {
241 inode_set_iversion_queried(inode,
242 be64_to_cpu(from->di_changecount));
243 ip->i_crtime = xfs_inode_from_disk_ts(from, from->di_crtime);
244 ip->i_diflags2 = be64_to_cpu(from->di_flags2);
245 ip->i_cowextsize = be32_to_cpu(from->di_cowextsize);
248 error = xfs_iformat_data_fork(ip, from);
251 if (from->di_forkoff) {
252 error = xfs_iformat_attr_fork(ip, from);
254 goto out_destroy_data_fork;
256 if (xfs_is_reflink_inode(ip))
257 xfs_ifork_init_cow(ip);
260 out_destroy_data_fork:
261 xfs_idestroy_fork(&ip->i_df);
265 /* Convert an incore timestamp to an ondisk timestamp. */
266 static inline xfs_timestamp_t
267 xfs_inode_to_disk_ts(
268 struct xfs_inode *ip,
269 const struct timespec64 tv)
271 struct xfs_legacy_timestamp *lts;
274 if (xfs_inode_has_bigtime(ip))
275 return cpu_to_be64(xfs_inode_encode_bigtime(tv));
277 lts = (struct xfs_legacy_timestamp *)&ts;
278 lts->t_sec = cpu_to_be32(tv.tv_sec);
279 lts->t_nsec = cpu_to_be32(tv.tv_nsec);
285 xfs_inode_to_disk_iext_counters(
286 struct xfs_inode *ip,
287 struct xfs_dinode *to)
289 if (xfs_inode_has_large_extent_counts(ip)) {
290 to->di_big_nextents = cpu_to_be64(xfs_ifork_nextents(&ip->i_df));
291 to->di_big_anextents = cpu_to_be32(xfs_ifork_nextents(&ip->i_af));
293 * We might be upgrading the inode to use larger extent counters
294 * than was previously used. Hence zero the unused field.
296 to->di_nrext64_pad = cpu_to_be16(0);
298 to->di_nextents = cpu_to_be32(xfs_ifork_nextents(&ip->i_df));
299 to->di_anextents = cpu_to_be16(xfs_ifork_nextents(&ip->i_af));
305 struct xfs_inode *ip,
306 struct xfs_dinode *to,
309 struct inode *inode = VFS_I(ip);
311 to->di_magic = cpu_to_be16(XFS_DINODE_MAGIC);
314 to->di_format = xfs_ifork_format(&ip->i_df);
315 to->di_uid = cpu_to_be32(i_uid_read(inode));
316 to->di_gid = cpu_to_be32(i_gid_read(inode));
317 to->di_projid_lo = cpu_to_be16(ip->i_projid & 0xffff);
318 to->di_projid_hi = cpu_to_be16(ip->i_projid >> 16);
320 to->di_atime = xfs_inode_to_disk_ts(ip, inode_get_atime(inode));
321 to->di_mtime = xfs_inode_to_disk_ts(ip, inode_get_mtime(inode));
322 to->di_ctime = xfs_inode_to_disk_ts(ip, inode_get_ctime(inode));
323 to->di_nlink = cpu_to_be32(inode->i_nlink);
324 to->di_gen = cpu_to_be32(inode->i_generation);
325 to->di_mode = cpu_to_be16(inode->i_mode);
327 to->di_size = cpu_to_be64(ip->i_disk_size);
328 to->di_nblocks = cpu_to_be64(ip->i_nblocks);
329 to->di_extsize = cpu_to_be32(ip->i_extsize);
330 to->di_forkoff = ip->i_forkoff;
331 to->di_aformat = xfs_ifork_format(&ip->i_af);
332 to->di_flags = cpu_to_be16(ip->i_diflags);
334 if (xfs_has_v3inodes(ip->i_mount)) {
336 to->di_changecount = cpu_to_be64(inode_peek_iversion(inode));
337 to->di_crtime = xfs_inode_to_disk_ts(ip, ip->i_crtime);
338 to->di_flags2 = cpu_to_be64(ip->i_diflags2);
339 to->di_cowextsize = cpu_to_be32(ip->i_cowextsize);
340 to->di_ino = cpu_to_be64(ip->i_ino);
341 to->di_lsn = cpu_to_be64(lsn);
342 memset(to->di_pad2, 0, sizeof(to->di_pad2));
343 uuid_copy(&to->di_uuid, &ip->i_mount->m_sb.sb_meta_uuid);
347 to->di_flushiter = cpu_to_be16(ip->i_flushiter);
348 memset(to->di_v2_pad, 0, sizeof(to->di_v2_pad));
351 xfs_inode_to_disk_iext_counters(ip, to);
354 static xfs_failaddr_t
355 xfs_dinode_verify_fork(
356 struct xfs_dinode *dip,
357 struct xfs_mount *mp,
360 xfs_extnum_t di_nextents;
361 xfs_extnum_t max_extents;
362 mode_t mode = be16_to_cpu(dip->di_mode);
363 uint32_t fork_size = XFS_DFORK_SIZE(dip, mp, whichfork);
364 uint32_t fork_format = XFS_DFORK_FORMAT(dip, whichfork);
366 di_nextents = xfs_dfork_nextents(dip, whichfork);
369 * For fork types that can contain local data, check that the fork
370 * format matches the size of local data contained within the fork.
372 * For all types, check that when the size says the should be in extent
373 * or btree format, the inode isn't claiming it is in local format.
375 if (whichfork == XFS_DATA_FORK) {
376 if (S_ISDIR(mode) || S_ISLNK(mode)) {
377 if (be64_to_cpu(dip->di_size) <= fork_size &&
378 fork_format != XFS_DINODE_FMT_LOCAL)
379 return __this_address;
382 if (be64_to_cpu(dip->di_size) > fork_size &&
383 fork_format == XFS_DINODE_FMT_LOCAL)
384 return __this_address;
387 switch (fork_format) {
388 case XFS_DINODE_FMT_LOCAL:
390 * No local regular files yet.
392 if (S_ISREG(mode) && whichfork == XFS_DATA_FORK)
393 return __this_address;
395 return __this_address;
397 case XFS_DINODE_FMT_EXTENTS:
398 if (di_nextents > XFS_DFORK_MAXEXT(dip, mp, whichfork))
399 return __this_address;
401 case XFS_DINODE_FMT_BTREE:
402 max_extents = xfs_iext_max_nextents(
403 xfs_dinode_has_large_extent_counts(dip),
405 if (di_nextents > max_extents)
406 return __this_address;
409 return __this_address;
414 static xfs_failaddr_t
415 xfs_dinode_verify_forkoff(
416 struct xfs_dinode *dip,
417 struct xfs_mount *mp)
419 if (!dip->di_forkoff)
422 switch (dip->di_format) {
423 case XFS_DINODE_FMT_DEV:
424 if (dip->di_forkoff != (roundup(sizeof(xfs_dev_t), 8) >> 3))
425 return __this_address;
427 case XFS_DINODE_FMT_LOCAL: /* fall through ... */
428 case XFS_DINODE_FMT_EXTENTS: /* fall through ... */
429 case XFS_DINODE_FMT_BTREE:
430 if (dip->di_forkoff >= (XFS_LITINO(mp) >> 3))
431 return __this_address;
434 return __this_address;
439 static xfs_failaddr_t
440 xfs_dinode_verify_nrext64(
441 struct xfs_mount *mp,
442 struct xfs_dinode *dip)
444 if (xfs_dinode_has_large_extent_counts(dip)) {
445 if (!xfs_has_large_extent_counts(mp))
446 return __this_address;
447 if (dip->di_nrext64_pad != 0)
448 return __this_address;
449 } else if (dip->di_version >= 3) {
450 if (dip->di_v3_pad != 0)
451 return __this_address;
459 struct xfs_mount *mp,
461 struct xfs_dinode *dip)
468 xfs_extnum_t nextents;
469 xfs_extnum_t naextents;
470 xfs_filblks_t nblocks;
472 if (dip->di_magic != cpu_to_be16(XFS_DINODE_MAGIC))
473 return __this_address;
475 /* Verify v3 integrity information first */
476 if (dip->di_version >= 3) {
477 if (!xfs_has_v3inodes(mp))
478 return __this_address;
479 if (!xfs_verify_cksum((char *)dip, mp->m_sb.sb_inodesize,
481 return __this_address;
482 if (be64_to_cpu(dip->di_ino) != ino)
483 return __this_address;
484 if (!uuid_equal(&dip->di_uuid, &mp->m_sb.sb_meta_uuid))
485 return __this_address;
488 /* don't allow invalid i_size */
489 di_size = be64_to_cpu(dip->di_size);
490 if (di_size & (1ULL << 63))
491 return __this_address;
493 mode = be16_to_cpu(dip->di_mode);
494 if (mode && xfs_mode_to_ftype(mode) == XFS_DIR3_FT_UNKNOWN)
495 return __this_address;
497 /* No zero-length symlinks/dirs. */
498 if ((S_ISLNK(mode) || S_ISDIR(mode)) && di_size == 0)
499 return __this_address;
501 fa = xfs_dinode_verify_nrext64(mp, dip);
505 nextents = xfs_dfork_data_extents(dip);
506 naextents = xfs_dfork_attr_extents(dip);
507 nblocks = be64_to_cpu(dip->di_nblocks);
509 /* Fork checks carried over from xfs_iformat_fork */
510 if (mode && nextents + naextents > nblocks)
511 return __this_address;
513 if (nextents + naextents == 0 && nblocks != 0)
514 return __this_address;
516 if (S_ISDIR(mode) && nextents > mp->m_dir_geo->max_extents)
517 return __this_address;
519 if (mode && XFS_DFORK_BOFF(dip) > mp->m_sb.sb_inodesize)
520 return __this_address;
522 flags = be16_to_cpu(dip->di_flags);
524 if (mode && (flags & XFS_DIFLAG_REALTIME) && !mp->m_rtdev_targp)
525 return __this_address;
527 /* check for illegal values of forkoff */
528 fa = xfs_dinode_verify_forkoff(dip, mp);
532 /* Do we have appropriate data fork formats for the mode? */
533 switch (mode & S_IFMT) {
538 if (dip->di_format != XFS_DINODE_FMT_DEV)
539 return __this_address;
544 fa = xfs_dinode_verify_fork(dip, mp, XFS_DATA_FORK);
549 /* Uninitialized inode ok. */
552 return __this_address;
555 if (dip->di_forkoff) {
556 fa = xfs_dinode_verify_fork(dip, mp, XFS_ATTR_FORK);
561 * If there is no fork offset, this may be a freshly-made inode
562 * in a new disk cluster, in which case di_aformat is zeroed.
563 * Otherwise, such an inode must be in EXTENTS format; this goes
564 * for freed inodes as well.
566 switch (dip->di_aformat) {
568 case XFS_DINODE_FMT_EXTENTS:
571 return __this_address;
574 return __this_address;
577 /* extent size hint validation */
578 fa = xfs_inode_validate_extsize(mp, be32_to_cpu(dip->di_extsize),
583 /* only version 3 or greater inodes are extensively verified here */
584 if (dip->di_version < 3)
587 flags2 = be64_to_cpu(dip->di_flags2);
589 /* don't allow reflink/cowextsize if we don't have reflink */
590 if ((flags2 & (XFS_DIFLAG2_REFLINK | XFS_DIFLAG2_COWEXTSIZE)) &&
591 !xfs_has_reflink(mp))
592 return __this_address;
594 /* only regular files get reflink */
595 if ((flags2 & XFS_DIFLAG2_REFLINK) && (mode & S_IFMT) != S_IFREG)
596 return __this_address;
598 /* don't let reflink and realtime mix */
599 if ((flags2 & XFS_DIFLAG2_REFLINK) && (flags & XFS_DIFLAG_REALTIME))
600 return __this_address;
602 /* COW extent size hint validation */
603 fa = xfs_inode_validate_cowextsize(mp, be32_to_cpu(dip->di_cowextsize),
604 mode, flags, flags2);
608 /* bigtime iflag can only happen on bigtime filesystems */
609 if (xfs_dinode_has_bigtime(dip) &&
610 !xfs_has_bigtime(mp))
611 return __this_address;
618 struct xfs_mount *mp,
619 struct xfs_dinode *dip)
623 if (dip->di_version < 3)
626 ASSERT(xfs_has_crc(mp));
627 crc = xfs_start_cksum_update((char *)dip, mp->m_sb.sb_inodesize,
629 dip->di_crc = xfs_end_cksum(crc);
633 * Validate di_extsize hint.
635 * 1. Extent size hint is only valid for directories and regular files.
636 * 2. FS_XFLAG_EXTSIZE is only valid for regular files.
637 * 3. FS_XFLAG_EXTSZINHERIT is only valid for directories.
638 * 4. Hint cannot be larger than MAXTEXTLEN.
639 * 5. Can be changed on directories at any time.
640 * 6. Hint value of 0 turns off hints, clears inode flags.
641 * 7. Extent size must be a multiple of the appropriate block size.
642 * For realtime files, this is the rt extent size.
643 * 8. For non-realtime files, the extent size hint must be limited
644 * to half the AG size to avoid alignment extending the extent beyond the
648 xfs_inode_validate_extsize(
649 struct xfs_mount *mp,
657 uint32_t extsize_bytes;
658 uint32_t blocksize_bytes;
660 rt_flag = (flags & XFS_DIFLAG_REALTIME);
661 hint_flag = (flags & XFS_DIFLAG_EXTSIZE);
662 inherit_flag = (flags & XFS_DIFLAG_EXTSZINHERIT);
663 extsize_bytes = XFS_FSB_TO_B(mp, extsize);
666 * This comment describes a historic gap in this verifier function.
668 * For a directory with both RTINHERIT and EXTSZINHERIT flags set, this
669 * function has never checked that the extent size hint is an integer
670 * multiple of the realtime extent size. Since we allow users to set
671 * this combination on non-rt filesystems /and/ to change the rt
672 * extent size when adding a rt device to a filesystem, the net effect
673 * is that users can configure a filesystem anticipating one rt
674 * geometry and change their minds later. Directories do not use the
675 * extent size hint, so this is harmless for them.
677 * If a directory with a misaligned extent size hint is allowed to
678 * propagate that hint into a new regular realtime file, the result
679 * is that the inode cluster buffer verifier will trigger a corruption
680 * shutdown the next time it is run, because the verifier has always
681 * enforced the alignment rule for regular files.
683 * Because we allow administrators to set a new rt extent size when
684 * adding a rt section, we cannot add a check to this verifier because
685 * that will result a new source of directory corruption errors when
686 * reading an existing filesystem. Instead, we rely on callers to
687 * decide when alignment checks are appropriate, and fix things up as
692 blocksize_bytes = XFS_FSB_TO_B(mp, mp->m_sb.sb_rextsize);
694 blocksize_bytes = mp->m_sb.sb_blocksize;
696 if ((hint_flag || inherit_flag) && !(S_ISDIR(mode) || S_ISREG(mode)))
697 return __this_address;
699 if (hint_flag && !S_ISREG(mode))
700 return __this_address;
702 if (inherit_flag && !S_ISDIR(mode))
703 return __this_address;
705 if ((hint_flag || inherit_flag) && extsize == 0)
706 return __this_address;
708 /* free inodes get flags set to zero but extsize remains */
709 if (mode && !(hint_flag || inherit_flag) && extsize != 0)
710 return __this_address;
712 if (extsize_bytes % blocksize_bytes)
713 return __this_address;
715 if (extsize > XFS_MAX_BMBT_EXTLEN)
716 return __this_address;
718 if (!rt_flag && extsize > mp->m_sb.sb_agblocks / 2)
719 return __this_address;
725 * Validate di_cowextsize hint.
727 * 1. CoW extent size hint can only be set if reflink is enabled on the fs.
728 * The inode does not have to have any shared blocks, but it must be a v3.
729 * 2. FS_XFLAG_COWEXTSIZE is only valid for directories and regular files;
730 * for a directory, the hint is propagated to new files.
731 * 3. Can be changed on files & directories at any time.
732 * 4. Hint value of 0 turns off hints, clears inode flags.
733 * 5. Extent size must be a multiple of the appropriate block size.
734 * 6. The extent size hint must be limited to half the AG size to avoid
735 * alignment extending the extent beyond the limits of the AG.
738 xfs_inode_validate_cowextsize(
739 struct xfs_mount *mp,
747 uint32_t cowextsize_bytes;
749 rt_flag = (flags & XFS_DIFLAG_REALTIME);
750 hint_flag = (flags2 & XFS_DIFLAG2_COWEXTSIZE);
751 cowextsize_bytes = XFS_FSB_TO_B(mp, cowextsize);
753 if (hint_flag && !xfs_has_reflink(mp))
754 return __this_address;
756 if (hint_flag && !(S_ISDIR(mode) || S_ISREG(mode)))
757 return __this_address;
759 if (hint_flag && cowextsize == 0)
760 return __this_address;
762 /* free inodes get flags set to zero but cowextsize remains */
763 if (mode && !hint_flag && cowextsize != 0)
764 return __this_address;
766 if (hint_flag && rt_flag)
767 return __this_address;
769 if (cowextsize_bytes % mp->m_sb.sb_blocksize)
770 return __this_address;
772 if (cowextsize > XFS_MAX_BMBT_EXTLEN)
773 return __this_address;
775 if (cowextsize > mp->m_sb.sb_agblocks / 2)
776 return __this_address;