Home | History | Annotate | Download | only in dumplfs
History log of /src/usr.sbin/dumplfs/dumplfs.c
RevisionDateAuthorComments
 1.67  14-Sep-2025  perseant Add -n flag to allow dumping of a given inode from an inode block (using
"-n ino@blockno") or every inode in a block (using "-n blockno").
 1.66  09-Feb-2024  andvar fix spelling mistakes, mainly in comments and log messages.
 1.65  23-Feb-2020  riastradh Fix userland references to LFS_ORPHAN_NEXTFREE.

Forgot to grep for these or do a full distribution build, oops!
 1.64  15-Jun-2018  christos branches: 1.64.2; 1.64.4;
PR/53367: Thomas Barabosch: Integer overflow in usr.sbin/dumplfs
While here use the "e" functions to always check for allocation errors.
 1.63  12-Aug-2016  dholland branches: 1.63.12;
If the number of inodes per block is zero, bail instead of using
uninitialized stack trash as a dinode pointer. Fixes PR 51409 where
"dumplfs /dev/zero" receives SIGSEGV.
 1.62  15-Jun-2016  riastradh <stdbool.h> for true and false.
 1.61  15-Oct-2015  dholland Enable lfs64 in dumplfs. Print LFS32/64 in the output header.
 1.60  10-Oct-2015  dholland Track down and fix two missing uses of SEGSUM_FINFOBASE().
 1.59  03-Oct-2015  dholland Use accessors for another batch of indirect block accesses, this time
in dumplfs.
 1.58  03-Oct-2015  dholland Apply IINFO in the other userland tools.
 1.57  01-Sep-2015  dholland The ifile's inode number is constant. (it is always 1)

Therefore, storing the value in the superblock and reading it out
again is silly and offers the opportunity for it to become corrupted.
So, don't do that (most of the code already didn't) and use the
existing constant instead. Initialize new 32-bit superblocks with
the value for the sake of old userland programs, but don't keep the
value in the 64-bit superblock at all.

(approved by Margo Seltzer)
 1.56  01-Sep-2015  dholland Make the inode fields in the 64-bit superblock 64 bits wide.
Reasoning as before.

Note that I am not going through and checking for 64->32 truncations
in inode numbers; I'm sure there are quite a few, but that's a project
for later.
 1.55  29-Aug-2015  dholland Bypass the ifile's double indirect block if the ifile size in blocks
is less than or equal to NDADDR + NINDIR, the number of blocks mapped
without getting to the double indirect block.

The code here was instead using NINDIR * ifpb (ifile entries per
block); this gives the number of ifile entries the indirect block can
map, but that isn't a useful number.

Caught by mlelstv.
 1.54  12-Aug-2015  dholland Hack up dinode usage to be 64 vs. 32 as needed. Part 1.

(This part changes the native lfs code; the ufs-derived code already
has 64 vs. 32 logic, but as aspects of it are unsafe, and don't
entirely interoperate cleanly with the lfs 64/32 stuff, pass 2 will be
rehashing that.)
 1.53  12-Aug-2015  dholland Provide 32-bit and 64-bit versions of FINFO.

This also entailed sorting out part of struct segment, as that
contains a pointer into the current FINFO data.
 1.52  12-Aug-2015  dholland Make 32-bit and 64-bit versions of SEGSUM.
Also fix some of the FINFO handling as it's closely entangled.
 1.51  12-Aug-2015  dholland Add IFILE32 and IFILE64 structures for the on-disk ifile entries.
Add and use accessors. There are also a bunch of places that cast and
I hope I've found them all...
 1.50  12-Aug-2015  dholland Make 32-bit and 64-bit versions of CLEANERINFO.

XXX: while this is written to disk, it seems like much of it would
XXX: be better set up as a commpage shared with the cleaner.
 1.49  02-Aug-2015  dholland Add a (draft) 64-bit superblock. Make things build again.

Add pieces of support for using both superblock types where
convenient, and specifically to the superblock accessors, but don't
actually enable it anywhere.

First substantive step on PR 50000.
 1.48  02-Aug-2015  dholland Use accessor functions for the version field of the lfs superblock.
I thought at first maybe the cases that test the version should be
rolled into the accessors, but on the whole I think the conclusion on
that is no.
 1.47  02-Aug-2015  dholland Second batch of 64 -> 32 truncations in lfs, along with more minor
tidyups and corrections in passing.
 1.46  02-Aug-2015  dholland Fix assorted 64 -> 32 truncations in lfs. Also, some minor tidyups and
corrections in passing.
 1.45  28-Jul-2015  dholland Add a new lfs header file: lfs_accessors.h.

This contains all the accessor functions and macros out of lfs.h.
Add an include of lfs_accessors.h after all uses of lfs.h... except
for code that wants to define its own struct lfs-alike that the
accessors are supposed to play along with. For these, set STRUCT_LFS
and include lfs_accessors.h after the necessary structure has been
defined, so that lfs_accessors.h can emit functions in terms of it.
 1.44  24-Jul-2015  dholland More lfs superblock accessors.
(This changes the rest of the code over; all the accessors were
already added.)

The difference between this commit and the previous one is arbitrary,
but the previous one passed the regression tests on its own so I'm
keeping it separate to help with any bisections that might be needed
in the future.
 1.43  24-Jul-2015  dholland Switch to accessor functions for elements of the LFS on-disk
superblock. This will allow switching between 32/64 bit forms on the
fly; it will also allow handling LFS_EI reasonably tidily. (That
currently doesn't work on the superblock.)

It also gets rid of cpp abuse in the form of fake structure member
macros.

Also, instead of doing sleep/wakeup on &lfs_avail and &lfs_nextseg
inside the on-disk superblock, add extra elements to the in-memory
struct lfs for this. (XXX: these should be changed to condvars, but
not right now)

XXX: this migrates a structure needed by the lfs code in libsa (struct
salfs) into lfs.h, where it doesn't belong, but for the time being
this is necessary in order to allow the accessors (and the various
lfs macros and other goop that relies on them) to compile.
 1.42  31-May-2015  hannken Use VFS_PROTOS() for lfs.
Rename conflicting struct lfs field "lfs_start" to "lfs_s0addr".

No functional change.
 1.41  18-Jun-2013  christos Prefix most of the cpp macros with lfs_ and LFS_ to avoid conflicts with ffs.
This was done so that boot blocks that want to compile both FFS and LFS in
the same file work.
 1.40  08-Jun-2013  dholland Use struct ulfs1_dinode instead of struct ufs1_dinode.
 1.39  22-Jan-2013  dholland Stuff UFS_ in front of a few of ufs's symbols to reduce namespace
pollution. Specifically:
ROOTINO -> UFS_ROOTINO
WINO -> UFS_WINO
NXADDR -> UFS_NXADDR
NDADDR -> UFS_NDADDR
NIADDR -> UFS_NIADDR
MAXSYMLINKLEN -> UFS_MAXSYMLINKLEN
MAXSYMLINKLEN_UFS[12] -> UFS[12]_MAXSYMLINKLEN (for consistency)

Sort out ext2fs's misuse of NDADDR and NIADDR; fortunately, these have
the same values in ext2fs and ffs.

No functional change intended.
 1.38  16-Feb-2010  mlelstv branches: 1.38.6; 1.38.12;
Read the padded superblocks to avoid problems with disks that have
larger sectors than 512 Bytes.
 1.37  21-Jul-2008  lukem Remove the \n and tabs from the __COPYRIGHT() strings.
Tweak to use a consistent format.
 1.36  16-Feb-2008  matt branches: 1.36.6;
cksum returns uint32_t, not u_long
 1.35  04-May-2007  joerg branches: 1.35.4;
Don't bail out if the ifile can't be found based on the superblocks.
As it is actually possible to find the positive based on the segment
dumps and some trying with -I/-i, it can be used to recover from bad
superblocks pointing to non-sense locations.
 1.34  01-Sep-2006  perseant Update dumplfs to reflect new segment flags and "orphaned" file status.
 1.33  21-Jul-2006  perseant Make dumplfs report the new SS_CLEAN flag.
 1.32  10-May-2006  perseant Fix yesterday's patch: use the correct field when printing partial segment
creation time in the version > 1 case.
 1.31  09-May-2006  perseant Report segment and partial-segment timestamps correctly on big-endian systems.
 1.30  24-Apr-2006  dsl Coverty CID 1693: free() buffer used reading fs info.
(I think this leaks 1 buffer per LFS segment being dumped!)
 1.29  19-Aug-2005  christos 64 bit inode changes
 1.28  07-Aug-2003  agc Move UCB-licensed code from 4-clause to 3-clause licence.

Patches provided by Joel Baker in PR 22366, verified by myself.
 1.27  16-Apr-2003  wiz Sync usage with man page.
 1.26  02-Apr-2003  fvdl Add support for UFS2. UFS2 is an enhanced FFS, adding support for
64 bit block pointers, extended attribute storage, and a few
other things.

This commit does not yet include the code to manipulate the extended
storage (for e.g. ACLs), this will be done later.

Originally written by Kirk McKusick and Network Associates Laboratories for
FreeBSD.
 1.25  07-Mar-2003  perseant Add option to check partial-segment data checksums.
 1.24  23-Feb-2003  perseant Make the "-O" (start filesystem offset) flag to newfs_lfs work correctly,
and update fsck_lfs and dumplfs to deal with it. Note that while the argument
to -O is given in disk sectors, it must be a multiple of the fragment size,
and although it can be lower than the label or superblock, it can't intersect
either.
 1.23  21-Feb-2003  simonb Show the address of segment 0.
 1.22  17-Feb-2003  perseant Add code to UBCify LFS. This is still behind "#ifdef LFS_UBC" for now
(there are still some details to work out) but expect that to go
away soon. To support these basic changes (creation of lfs_putpages,
lfs_gop_write, mods to lfs_balloc) several other changes were made, to
wit:

* Create a writer daemon kernel thread whose purpose is to handle page
writes for the pagedaemon, but which also takes over some of the
functions of lfs_check(). This thread is started the first time an
LFS is mounted.

* Add a "flags" parameter to GOP_SIZE. Current values are
GOP_SIZE_READ, meaning that the call should return the size of the
in-core version of the file, and GOP_SIZE_WRITE, meaning that it
should return the on-disk size. One of GOP_SIZE_READ or
GOP_SIZE_WRITE must be specified.

* Instead of using malloc(...M_WAITOK) for everything, reserve enough
resources to get by and use malloc(...M_NOWAIT), using the reserves if
necessary. Use the pool subsystem for structures small enough that
this is feasible. This also obsoletes LFS_THROTTLE.

And a few that are not strictly necessary:

* Moves the LFS inode extensions off onto a separately allocated
structure; getting closer to LFS as an LKM. "Welcome to 1.6O."

* Unified GOP_ALLOC between FFS and LFS.

* Update LFS copyright headers to correct values.

* Actually cast to unsigned in lfs_shellsort, like the comment says.

* Keep track of which segments were empty before the previous
checkpoint; any segments that pass two checkpoints both dirty and
empty can be summarily cleaned. Do this. Right now lfs_segclean
still works, but this should be turned into an effectless
compatibility syscall.
 1.21  28-Jan-2003  mrg make this build on alpha after daddr_t->64bit
 1.20  24-Jan-2003  fvdl Bump daddr_t to 64 bits. Replace it with int32_t in all places where
it was used on-disk, so that on-disk formats remain the same.
Remove ufs_daddr_t and ufs_lbn_t for the time being.
 1.19  13-Jul-2001  perseant Merge the short-lived perseant-lfsv2 branch into the trunk.

Kernels and tools understand both v1 and v2 filesystems; newfs_lfs
generates v2 by default. Changes for the v2 layout include:

- Segments of non-PO2 size and arbitrary block offset, so these can be
matched to convenient physical characteristics of the partition (e.g.,
stripe or track size and offset).

- Address by fragment instead of by disk sector, paving the way for
non-512-byte-sector devices. In theory fragments can be as large
as you like, though in reality they must be smaller than MAXBSIZE in size.

- Use serial number and filesystem identifier to ensure that roll-forward
doesn't get old data and think it's new. Roll-forward is enabled for
v2 filesystems, though not for v1 filesystems by default.

- The inode free list is now a tailq, paving the way for undelete (undelete
is not yet implemented, but can be without further non-backwards-compatible
changes to disk structures).

- Inode atime information is kept in the Ifile, instead of on the inode;
that is, the inode is never written *just* because atime was changed.
Because of this the inodes remain near the file data on the disk, rather
than wandering all over as the disk is read repeatedly. This speeds up
repeated reads by a small but noticeable amount.

Other changes of note include:

- The ifile written by newfs_lfs can now be of arbitrary length, it is no
longer restricted to a single indirect block.

- Fixed an old bug where ctime was changed every time a vnode was created.
I need to look more closely to make sure that the times are only updated
during write(2) and friends, not after-the-fact during a segment write,
and certainly not by the cleaner.
 1.18  05-Jan-2001  lukem branches: 1.18.2;
use %ll_ instead of the less standard %q_
 1.17  13-Nov-2000  perseant Report, and detect and correct inconsistencies in, the number of clean
segments. Patches from Jesse Off <joff@gci-net.com> (PR #11470).
 1.16  25-Aug-2000  toshii Defined datobyte(fs, da) macro, to ensure cast to off_t.
Fixes overflows with >2GB partitions. Reviewed by <enami@netbsd.org>.
 1.15  25-Jun-2000  perseant use -s option to shorten the list of SEGUSEs printed as well as whole segments
 1.14  14-Jun-2000  perseant branches: 1.14.2;
Assorted changes/fixes to dumplfs:

Add flags "-b" and "-I" to dumplfs, to allow the user to specify the
location of the superblock and Ifile inode, respectively.

Don't print "corrupt segment header" any more for leftover slivers of
space too close to the next segment to write a partial-segment. In the
event that there was no such sliver, the segment still ends; recognize
this and print out the segment number, and superblock if asked.

Document all the flags in the man page.

Print the partial-segment write flags (SS_DIROP, SS_CONT).

Make the "-a" flag output look slightly better.

Change all hex numbers to lowercase, instead of having some upper and
some lower.
 1.13  02-May-1999  perseant branches: 1.13.6;
Reversed (corrected) sense of superblock timestamp comparison; added the
disk address of the reported superblock to the "master superblock" line
of the report.
 1.12  11-Sep-1998  pk Deal with superblock changes; from PR#6032.
 1.11  30-Aug-1998  nathanw Add braces to satisfy egcs.
 1.10  27-Aug-1998  ross Add {} pairs to shut up egcs.
 1.9  03-Mar-1998  thorpej Fix printf formats on Alpha: cast quads to long long for printing w/
%qd.
 1.8  01-Mar-1998  fvdl Merge with Lite2 + local changes
 1.7  14-Dec-1995  thorpej Make this compile with -Werror.
 1.6  07-Jun-1995  cgd typeof(timeval.tv_sec) != time_t
 1.5  18-Mar-1995  cgd convert to new RCS Id conventions; reduce my headache
 1.4  05-Dec-1994  cgd more cleanups from Jim Jegers, passed over by me.
 1.3  31-Oct-1994  cgd correct pointer type.
 1.2  23-Sep-1994  mycroft err(3)/warn(3) cleanup
 1.1  08-Jun-1994  mycroft branches: 1.1.1;
Update from 4.4-Lite, with local changes.
 1.1.1.2  16-Sep-1997  lukem imported from lite-2
 1.1.1.1  13-Jun-1994  mycroft Import 4.4-Lite version.
 1.13.6.1  22-Jun-2000  minoura Sync w/ netbsd-1-5-base.
 1.14.2.2  03-Feb-2001  he Pull up revision 1.17 (requested by perseant):
Let dumplfs report lfs_nclean and lfs_dmeta.
 1.14.2.1  28-Aug-2000  toshii Pullup revision 1.16 (approved by thorpej):
Define datobyte(fs, da) macro, to ensure cast to off_t. Fixes PR#9890.
 1.18.2.5  10-Jul-2001  perseant Properly initialize and report the inode free list tail.
 1.18.2.4  02-Jul-2001  perseant Change disk addressing unit to be the fragment, instead of the disk sector.
All quantities in the superblock, inodes, indirect blocks, etc. refer now
to this abstract unit (called "fsb" as it is in FFS) instead of disk sectors;
as a consequence segment summary blocks have to be multiples of a fragment in
size. In v1 filesystems, compatibility code ensures that 1 fsb == 1 sector,
regardless of fragment size.

Fragments can now range in size between 512 and 32k; in the event that
LFS_LABELPAD (8k) is smaller than the disk address unit size, an extra
proto-superblock is kept at 8k from the beginning of the disk, to be used
*only* to locate the real superblocks. (Not all of the userland knows about
this yet.)

Almost all of this was done not by me, but by joff.
 1.18.2.3  30-Jun-2001  perseant Fixes, from joff, for correct compatibility operation of fsck_lfs, dumplfs,
lfs_cleanerd; correct usage message from dumplfs.
 1.18.2.2  29-Jun-2001  perseant Get rid of __P(), protoizing where it had not already been done
 1.18.2.1  27-Jun-2001  perseant Import of what I've been calling "LFSv2", that is, LFS with some features
added that require changes to the on-disk data structures. These include:

- 64-bit time in everything but inodes
- User-specified segment offset, and segment size no longer
restricted to PO2.
- Serial number on segment summaries in addition to timestamp, and
a new volume identifier, to make roll-forward feasible without
fear of finding old data and thinking it was new.

Although I think this version works at least as well as what's on the trunk,
we're not done yet; hence this commit is going in on a branch and not on
the trunk. Enhancements that are not here yet include fragment addressing,
like FFS does, instead of block addressing.
 1.35.4.1  23-Mar-2008  matt sync with HEAD
 1.36.6.1  18-Sep-2008  wrstuden Sync with wrstuden-revivesa-base-2.
 1.38.12.2  23-Jun-2013  tls resync from head
 1.38.12.1  25-Feb-2013  tls resync with head
 1.38.6.2  22-May-2014  yamt sync with head.

for a reference, the tree before this commit was tagged
as yamt-pagecache-tag8.

this commit was splitted into small chunks to avoid
a limitation of cvs. ("Protocol error: too many arguments")
 1.38.6.1  23-Jan-2013  yamt sync with head
 1.63.12.1  25-Jun-2018  pgoyette Sync with HEAD
 1.64.4.1  17-Aug-2020  martin Pull up following revision(s) (requested by riastradh in ticket #1050):

sys/ufs/lfs/lfs_subr.c: revision 1.101
sys/ufs/lfs/lfs_subr.c: revision 1.102
sys/ufs/lfs/lfs_inode.c: revision 1.158
sys/ufs/lfs/lfs_inode.h: revision 1.25
sys/ufs/lfs/lfs_balloc.c: revision 1.95
sys/ufs/lfs/lfs_pages.c: revision 1.21
sys/ufs/lfs/lfs_vnops.c: revision 1.330
sys/ufs/lfs/lfs_alloc.c: revision 1.140 (patch)
sys/ufs/lfs/lfs_alloc.c: revision 1.141 (patch)
lib/libp2k/p2k.c: revision 1.72
sys/ufs/lfs/lfs.h: revision 1.205
sys/ufs/lfs/lfs.h: revision 1.206
sys/ufs/lfs/lfs_segment.c: revision 1.284
sys/ufs/lfs/lfs.h: revision 1.207
sys/ufs/lfs/lfs_segment.c: revision 1.285
sys/ufs/lfs/lfs_debug.c: revision 1.55
sys/ufs/lfs/lfs_rename.c: revision 1.23
usr.sbin/dumplfs/dumplfs.c: revision 1.65
sys/ufs/lfs/lfs_vfsops.c: revision 1.371
sys/arch/i386/stand/efiboot/bootx64/Makefile: revision 1.3
sys/ufs/lfs/lfs_vfsops.c: revision 1.372
sys/ufs/lfs/lfs_vfsops.c: revision 1.373
sbin/fsck_lfs/pass1.c: revision 1.46
sys/ufs/lfs/lfs_vnops.c: revision 1.326
sys/ufs/lfs/lfs_vnops.c: revision 1.327
sys/ufs/lfs/lfs_vfsops.c: revision 1.375 (patch)
sys/ufs/lfs/lfs_vnops.c: revision 1.328
sys/ufs/lfs/lfs_subr.c: revision 1.98
sys/ufs/lfs/lfs_extern.h: revision 1.116
sys/ufs/lfs/lfs_vnops.c: revision 1.329
sys/ufs/lfs/lfs_subr.c: revision 1.99
sys/ufs/lfs/lfs_extern.h: revision 1.117
sys/ufs/lfs/lfs_accessors.h: revision 1.49
sys/ufs/lfs/lfs_extern.h: revision 1.118
sys/rump/fs/lib/liblfs/Makefile: revision 1.15
sys/ufs/lfs/lfs_bio.c: revision 1.146 (patch)
sys/ufs/lfs/lfs_bio.c: revision 1.147
sys/ufs/lfs/lfs_subr.c: revision 1.100

Fix kassert in lfs by initializing vp first.

Use a marker node to iterate lfs_dchainhd / i_lfs_dchain.

I believe elements can be removed while the lock is dropped,
including the next node we're hanging on to.

Just use VOP_BWRITE for lfs_bwrite_log.
Hope this doesn't cause trouble with vfs_suspend.

Teach lfs to transition ro<->rw.

Prevent new dirops while we issue lfs_flush_dirops.

lfs_flush_dirops assumes (by KASSERT((ip->i_state & IN_ADIROP) == 0))
that vnodes on the dchain will not become involved in active dirops
even while holding no other locks (lfs_lock, v_interlock), so we must
set lfs_writer here. All other callers already set lfs_writer.

We set fs->lfs_writer++ without explicitly doing lfs_writer_enter
because
(a) we already waited for the dirops to drain, and
(b) we hold lfs_lock and cannot drop it before setting lfs_writer.

Assert lfs_writer where I think we can now prove it.

Serialize access to the splay tree with lfs_lock.

Change some cheap KDASSERT into KASSERT.

Take a reference and fix assertions in lfs_flush_dirops.
Fixes panic:
KASSERT((ip->i_state & IN_ADIROP) == 0) at lfs_vnops.c:1670
lfs_flush_dirops
lfs_check
lfs_setattr
VOP_SETATTR
change_mode
sys_fchmod
syscall

This assertion -- and the assertion that vp->v_uflag has VU_DIROP set
-- is valid only until we release lfs_lock, because we may race with
lfs_unmark_dirop which will remove the nodes and change the flags.

Further, vp itself is valid only as long as it is referenced, which it
is as long as it's on the dchain, but lfs_unmark_dirop drops the
dchain's reference.

Don't lfs_writer_enter while holding v_interlock.

There's no need to lfs_writer_enter at all here, as far as I can see.
lfs_flush_fs will do it for us.

Break deadlock in PR kern/52301.

The lock order is lfs_writer -> lfs_seglock. The problem in 52301 is
that lfs_segwrite violates this lock order by sometimes doing
lfs_seglock -> lfs_writer, either (a) when doing a checkpoint or (b),
opportunistically, when there are no dirops pending. Both cases can
deadlock, because dirops sometimes take the seglock (lfs_truncate,
lfs_valloc, lfs_vfree):
(a) There may be dirops pending, and they may be waiting for the
seglock, so we can't wait for them to complete while holding the
seglock.
(b) The test for fs->lfs_dirops == 0 happens unlocked, and the state
may change by the time lfs_writer_enter acquires lfs_lock.

To resolve this in each case:
(a) Do lfs_writer_enter before lfs_seglock, since we will need it
unconditionally anyway. The worst performance impact of this should
be that some dirops get delayed a little bit.
(b) Create a new lfs_writer_tryenter to use at this point so that the
test for fs->lfs_dirops == 0 and the acquisition of lfs_writer happen
atomically under lfs_lock.

Initialize/destroy lfs_allclean_wakeup in modcmd, not lfs_mountfs.

Fixes reloading lfs.kmod.

In lfs_update, hold lfs_writer around lfs_vflush.

Otherwise, we might do
lfs_vflush
-> lfs_seglock
-> lfs_segwait(SEGM_CKP)
-> lfs_writer_enter
which is the reverse of the lfs_writer -> lfs_seglock ordering.

Call lfs_orphan in lfs_rename while we're still in the dirop.
lfs_writer_enter can't fail; keep it simple and don't pretend it can.

Assert that mtsleep can't fail either -- it doesn't catch signals and
there's no timeout.

Teach LFS_ORPHAN_NEXTFREE about lfs64.

Dust off the orphan detection code and try to make it work.

Fix !DIAGNOSTIC compile

Fix userland references to LFS_ORPHAN_NEXTFREE.

Forgot to grep for these or do a full distribution build, oops!

Fix missing <sys/evcnt.h> by removing the evcnts instead.

Just wanted to confirm that a race might happen, and indeed it did.
These serve little diagnostic value otherwise.

OR into bp->b_cflags; don't overwrite.

CTASSERT lfs on-disk structure sizes.

Avoid misaligned access to lfs64 on-disk records in memory.
lfs64 directory entries are only 32-bit aligned in order to conserve
space in directory blocks, and we had a hack to stuff a 64-bit inode
in them. This replaces the hack by __aligned(4) __packed, and goes
further:

1. It's not clear that all the other lfs64 data structures are 64-bit
aligned on disk to begin with. We can go through these later and
upgrade them from
struct foo64 {
...
} __aligned(4) __packed;
union foo {
struct foo64 f64;
...
};
to
struct foo64 {
...
};
union foo {
struct foo64 f64 __aligned(8);
...
} __aligned(4) __packed;
if we really want to take advantage of 64-bit memory accesses.
However, the __aligned(4) __packed must remain on the union
because:
2. We access even the lfs32 data structures via a union that has
lfs64 members, and it turns out that compilers will assume access
through a union with 64-bit aligned members implies the whole
union has 64-bit alignment, even if we're only accessing a 32-bit
aligned member.

Fix clang build after packed lfs64 accessor change.

Suppress spurious address-of-packed error in rump lfs too.
 1.64.2.1  08-Apr-2020  martin Merge changes from current as of 20200406

RSS XML Feed