Al Viro reports that generic/231 fails frequently on XFS and bisected
the problem to the following commit:
5d11fb4b xfs: rework zero range to prevent invalid i_size updates
... which is just the first commit that happens to cause fsx to
reproduce the problem. fsx reproduces via zero range calls. The
aforementioned commit overhauls zero range to use hole punch and
fallocate. As it turns out, the problem is reproducible on demand using
basic hole punch as follows:
$ mkfs.xfs -f -m crc=1,finobt=1 <dev>
$ mount <dev> /mnt -o uquota
$ xfs_io -f -c "falloc 0 50m" /mnt/file
$ for i in $(seq 1 20); do xfs_io -c "fpunch ${i}m 32k" /mnt/file; done
$ rm -f /mnt/file
$ repquota -us /mnt
...
User used soft hard grace used soft hard grace
----------------------------------------------------------------------
root -- 32K 0K 0K 3 0 0
A file is allocated with a single 50m extent. The extent count increases
via hole punches until the bmap converts to btree format. The file is
removed but quota reports 32k of space usage for the user. This
reservation is effectively leaked for the lifetime of the mount.
The reason this occurs is because the quota block reservation tracking
is confused when a transaction happens to free and allocate blocks at
the same time. Consider the following sequence of events:
- tp is allocated from xfs_free_file_space() and reserves several blocks
for btree management. Blocks are reserved against the dquot and marked
as such in the transaction (qtrx->qt_blk_res).
- 8 blocks are accounted free when the 32k range is punched out.
xfs_trans_mod_dquot() is called with XFS_TRANS_DQ_BCOUNT and sets
->qt_bcount_delta to -8.
- Subsequently, a block is allocated against the same transaction by
xfs_bmap_extents_to_btree() for btree conversion. A call to
xfs_trans_mod_dquot() increases qt_blk_res_used to 1 and qt_bcount_delta
to -7.
- The transaction is dup'd and committed by xfs_bmap_finish().
xfs_trans_dup_dqinfo() sets the first transaction up such that it has a
matching qt_blk_res and qt_blk_res_used of 1. The remaining unused
reservation is transferred to the duplicate tp.
When the transactions are committed, the dquots are fixed up in
xfs_trans_apply_dquot_deltas() according to one of two methods:
1.) If the transaction holds a block reservation (->qt_blk_res != 0),
_only_ the unused portion reservation is unaccounted from the dquot.
Note that the tp duplication behavior of xfs_bmap_finish() makes it such
that qt_blk_res is typically 0 for tp's with unused reservation.
2.) Otherwise, the dquot is fixed up based on the block delta
(->qt_bcount_delta) created by the transaction.
Therefore, if a transaction has a negative qt_bcount_delta and positive
qt_blk_res_used, the former set of blocks that have been removed from
the file are never factored out of the in-core dquot reservation.
Instead, *_apply_dquot_deltas() sees 1 block used out of a 1 block
reservation and believes there is nothing to fix up. The on-disk
d_bcount is updated independently from qt_bcount_delta, and thus is
correct (and allows the quota usage to correct on remount).
To deal with this situation, we effectively want the "used reservation"
part of the transaction to be consistent with any freed blocks with
respect to quota tracking. For example, if 8 blocks are freed, the
subsequent single block allocation does not need to consume the initial
reservation made by the tp. Instead, it simply borrows one from the
previously freed. One possible implementation of such borrowing is to
avoid the blks_res_used increment when bcount_delta is negative. This
alone is flawed logic in that it only handles the case where blocks are
freed before allocated, however.
Rather than add more complexity to manage synchronization between
bcount_delta and blks_res_used, kill the latter entirely. blk_res_used
is only updated in one place and always in sync with delta_bcount.
Therefore, the net block reservation consumption of the transaction is
always available from bcount_delta. Calculate the reservation
consumption on the fly where necessary based on whether the tp has a
reservation and results in a positive net block delta on the inode.
Reported-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Parts of userspace want to be able to read and modify dquot buffers
(e.g. xfs_db) so we need to split out the reading and writing of
these buffers so it is easy to shared code with libxfs in userspace.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ben Myers <bpm@sgi.com>
All of the buffer operations structures are needed to be exported
for xfs_db, so move them all to a common location rather than
spreading them all over the place. They are verifying the on-disk
format, so while xfs_format.h might be a good place, it is not part
of the on disk format.
Hence we need to create a new header file that we centralise these
related definitions. Start by moving the bffer operations
structures, and then also move all the other definitions that have
crept into xfs_log_format.h and xfs_format.h as there was no other
shared header file to put them in.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ben Myers <bpm@sgi.com>
So move it to a header file shared with userspace.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
Use uint32 from init_user_ns for xfs internal uid/gid
representation in xfs_icdinode, xfs_dqid_t.
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Dwight Engen <dwight.engen@oracle.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
There are a lot of quota flag definitions that are shared by user
and kernel space. Move them all to xfs_quota_defs.h so we can
unshare xfs_quota.h and remove the __KERNEL__ regions from it.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
The on disk format definitions of the on-disk dquot, log formats and
quota off log formats are all intertwined with other definitions for
quotas. Separate them out into their own header file so they can
easily be shared with userspace.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
During the review of seperate pquota inode patches, David noticed
that the test to detect all quotas being turned off was
incorrect, and hence the block was not freeing all the quota
information.
The check made sense in Irix, but in Linux, quota is turned off
one at a time, which makes the test invalid for Linux.
This problem existed since XFS was ported to Linux.
David suggested to fix the problem by detecting when all quotas are
turned off by checking m_qflags.
Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
Add project quota changes to all the places where group quota field
is used:
* add separate project quota members into various structures
* split project quota and group quotas so that instead of overriding
the group quota members incore, the new project quota members are
used instead
* get rid of usage of the OQUOTA flag incore, in favor of separate
group and project quota flags.
* add a project dquot argument to various functions.
Not using the pquotino field from superblock yet.
Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
During review of the separate project quota inode patches, it became
obvious that the dquot log reservation calculation underestimated
the number dquots that can be modified in a transaction. This has
it's roots way back in the Irix quota implementation.
That is, when quotas were first implemented in XFS, it only
supported user and project quotas as Irix did not have group quotas.
Hence the worst case operation involving dquot modification was
calculated to involve 2 user dquots and 1 project dquot or 1 user
dequot and 2 project dquots. i.e. 3 dquots. This was determined back
in 1996, and has remained unchanged ever since.
However, back in 2001, the Linux XFS port dropped all support for
project quota and implmented group quotas over the top. This was
effectively done with a search-and-replace of project with group,
and as such the log reservation was not changed. However, with the
advent of group quotas, chmod and rename now could modify more than
3 dquots in a single transaction - both could modify 4 dquots. Hence
this log reservation has been wrong for a long time.
In 2005, project quota support was reintroduced into Linux, but it
was implemented to be mutually exclusive to group quotas and so this
didn't add any new changes to the dquot log reservation. Hence when
project quotas were in use (rather than group quotas) the log
reservation was again valid, just like in the Irix days.
Now, with the addition of the separate project quota inode, group
and project quotas are no longer mutually exclusive, and hence
operations can now modify three dquots per inode where previously it
was only two. The worst case here is the rename transaction, which
can allocate/free space on two different directory inodes, and if
they have different uid/gid/prid configurations and are world
writeable, then rename can actually modify 6 different dquots now.
Further, the dquot log reservation doesn't take into account the
space used by the dquot log format structure that precedes the dquot
that is logged, and hence further underestimates the worst case
log space required by dquots during a transaction. This has been
missing since the first commit in 1996.
Hence the worst case log reservation needs to be increased from 3 to
6, and it needs to take into account a log format header for each of
those dquots.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
Remove all incore use of XFS_OQUOTA_ENFD and XFS_OQUOTA_CHKD. Instead,
start using XFS_GQUOTA_.* XFS_PQUOTA_.* counterparts for GQUOTA and
PQUOTA respectively.
On-disk copy still uses XFS_OQUOTA_ENFD and XFS_OQUOTA_CHKD.
Read and write of the superblock does the conversion from *OQUOTA*
to *[PG]QUOTA*.
Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
Calculating dquot CRCs when the backing buffer is written back just
doesn't work reliably. There are several places which manipulate
dquots directly in the buffers, and they don't calculate CRCs
appropriately, nor do they always set the buffer up to calculate
CRCs appropriately.
Firstly, if we log a dquot buffer (e.g. during allocation) it gets
logged without valid CRC, and so on recovery we end up with a dquot
that is not valid.
Secondly, if we recover/repair a dquot, we don't have a verifier
attached to the buffer and hence CRCs are not calculated on the way
down to disk.
Thirdly, calculating the CRC after we've changed the contents means
that if we re-read the dquot from the buffer, we cannot verify the
contents of the dquot are valid, as the CRC is invalid.
So, to avoid all the dquot CRC errors that are being detected by the
read verifier, change to using the same model as for inodes. That
is, dquot CRCs are calculated and written to the backing buffer at
the time the dquot is flushed to the backing buffer. If we modify
the dquot directly in the backing buffer, calculate the CRC
immediately after the modification is complete. Hence the dquot in
the on-disk buffer should always have a valid CRC.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
Use the reserved space in struct xfs_dqblk to store a UUID and a crc
for the quota blocks.
[dchinner@redhat.com] Add a LSN field and update for current verifier
infrastructure.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
Define new macro XFS_ALL_QUOTA_ACTIVE and simply some usage
of quota macros.
Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ben Myers <bpm@sgi.com>
Just read the id 0 dquot from disk directly in xfs_qm_init_quotainfo instead
of going through dqget and requiring a special flag to not add the dquot to
any lists.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
Introduce a new XFS_DQ_FREEING flag that tells lookup and mplist walks
to skip a dquot that is beeing freed, and use this avoid the trylock
on the hash and mplist locks in xfs_qm_dqreclaim_one. Also simplify
xfs_dqpurge by moving the inodes to a dispose list after marking them
XFS_DQ_FREEING and avoid the locker ordering constraints.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
Do not remove dquots from the freelist when we grab a reference to them in
xfs_qm_dqlookup, but leave them on the freelist util scanning notices that
they have a reference. This speeds up the lookup fastpath, and greatly
simplifies the lock ordering constraints. Note that the same scheme is
used by the VFS inode and dentry caches.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
Free dquots when purging them during umount instead of keeping them around
on the freelist in a degraded state. The out of order locking in
xfs_qm_dqpurge will be removed again later in this series.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
Now that we can't have any dirty dquots around that aren't in the AIL we
can get rid of the explicit dquot syncing from xfssyncd and xfs_fs_sync_fs
and instead rely on AIL pushing to write out any quota updates.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
Convert the xfs log operations to use the new error logging
interfaces. This removes the xlog_{warn,panic} wrappers and makes
almost all errors emit the device they belong to instead of just
refering to "XFS".
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Alex Elder <aelder@sgi.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Andi Kleen reported that gcc-4.5 gives lots of warnings for him
inside the XFS code. It turned out most of them are due to the
quota stubs beeing macros, and gcc now complaining about macros
evaluating to 0 that are not assigned to variables.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
dquots are never flushed asynchronously. Remove the flag and the
async write support from the flush function. Make the default flush
a delwri flush to make the inode flush code, which leaves the
XFS_QMOPT_SYNC the only flag remaining. Convert that to use
SYNC_WAIT instead, just like the inode flush code.
V2:
- just pass flush flags straight through
Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
The option is unused and one of the few remaining users of
xfs_bawrite, so let's get rid of it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
Convert the old xfs tracing support that could only be used with the
out of tree kdb and xfsidbg patches to use the generic event tracer.
To use it make sure CONFIG_EVENT_TRACING is enabled and then enable
all xfs trace channels by:
echo 1 > /sys/kernel/debug/tracing/events/xfs/enable
or alternatively enable single events by just doing the same in one
event subdirectory, e.g.
echo 1 > /sys/kernel/debug/tracing/events/xfs/xfs_ihold/enable
or set more complex filters, etc. In Documentation/trace/events.txt
all this is desctribed in more detail. To reads the events do a
cat /sys/kernel/debug/tracing/trace
Compared to the last posting this patch converts the tracing mostly to
the one tracepoint per callsite model that other users of the new
tracing facility also employ. This allows a very fine-grained control
of the tracing, a cleaner output of the traces and also enables the
perf tool to use each tracepoint as a virtual performance counter,
allowing us to e.g. count how often certain workloads git various
spots in XFS. Take a look at
http://lwn.net/Articles/346470/
for some examples.
Also the btree tracing isn't included at all yet, as it will require
additional core tracing features not in mainline yet, I plan to
deliver it later.
And the really nice thing about this patch is that it actually removes
many lines of code while adding this nice functionality:
fs/xfs/Makefile | 8
fs/xfs/linux-2.6/xfs_acl.c | 1
fs/xfs/linux-2.6/xfs_aops.c | 52 -
fs/xfs/linux-2.6/xfs_aops.h | 2
fs/xfs/linux-2.6/xfs_buf.c | 117 +--
fs/xfs/linux-2.6/xfs_buf.h | 33
fs/xfs/linux-2.6/xfs_fs_subr.c | 3
fs/xfs/linux-2.6/xfs_ioctl.c | 1
fs/xfs/linux-2.6/xfs_ioctl32.c | 1
fs/xfs/linux-2.6/xfs_iops.c | 1
fs/xfs/linux-2.6/xfs_linux.h | 1
fs/xfs/linux-2.6/xfs_lrw.c | 87 --
fs/xfs/linux-2.6/xfs_lrw.h | 45 -
fs/xfs/linux-2.6/xfs_super.c | 104 ---
fs/xfs/linux-2.6/xfs_super.h | 7
fs/xfs/linux-2.6/xfs_sync.c | 1
fs/xfs/linux-2.6/xfs_trace.c | 75 ++
fs/xfs/linux-2.6/xfs_trace.h | 1369 +++++++++++++++++++++++++++++++++++++++++
fs/xfs/linux-2.6/xfs_vnode.h | 4
fs/xfs/quota/xfs_dquot.c | 110 ---
fs/xfs/quota/xfs_dquot.h | 21
fs/xfs/quota/xfs_qm.c | 40 -
fs/xfs/quota/xfs_qm_syscalls.c | 4
fs/xfs/support/ktrace.c | 323 ---------
fs/xfs/support/ktrace.h | 85 --
fs/xfs/xfs.h | 16
fs/xfs/xfs_ag.h | 14
fs/xfs/xfs_alloc.c | 230 +-----
fs/xfs/xfs_alloc.h | 27
fs/xfs/xfs_alloc_btree.c | 1
fs/xfs/xfs_attr.c | 107 ---
fs/xfs/xfs_attr.h | 10
fs/xfs/xfs_attr_leaf.c | 14
fs/xfs/xfs_attr_sf.h | 40 -
fs/xfs/xfs_bmap.c | 507 +++------------
fs/xfs/xfs_bmap.h | 49 -
fs/xfs/xfs_bmap_btree.c | 6
fs/xfs/xfs_btree.c | 5
fs/xfs/xfs_btree_trace.h | 17
fs/xfs/xfs_buf_item.c | 87 --
fs/xfs/xfs_buf_item.h | 20
fs/xfs/xfs_da_btree.c | 3
fs/xfs/xfs_da_btree.h | 7
fs/xfs/xfs_dfrag.c | 2
fs/xfs/xfs_dir2.c | 8
fs/xfs/xfs_dir2_block.c | 20
fs/xfs/xfs_dir2_leaf.c | 21
fs/xfs/xfs_dir2_node.c | 27
fs/xfs/xfs_dir2_sf.c | 26
fs/xfs/xfs_dir2_trace.c | 216 ------
fs/xfs/xfs_dir2_trace.h | 72 --
fs/xfs/xfs_filestream.c | 8
fs/xfs/xfs_fsops.c | 2
fs/xfs/xfs_iget.c | 111 ---
fs/xfs/xfs_inode.c | 67 --
fs/xfs/xfs_inode.h | 76 --
fs/xfs/xfs_inode_item.c | 5
fs/xfs/xfs_iomap.c | 85 --
fs/xfs/xfs_iomap.h | 8
fs/xfs/xfs_log.c | 181 +----
fs/xfs/xfs_log_priv.h | 20
fs/xfs/xfs_log_recover.c | 1
fs/xfs/xfs_mount.c | 2
fs/xfs/xfs_quota.h | 8
fs/xfs/xfs_rename.c | 1
fs/xfs/xfs_rtalloc.c | 1
fs/xfs/xfs_rw.c | 3
fs/xfs/xfs_trans.h | 47 +
fs/xfs/xfs_trans_buf.c | 62 -
fs/xfs/xfs_vnodeops.c | 8
70 files changed, 2151 insertions(+), 2592 deletions(-)
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
Fix warnings about unitialized dquot variables by making sure
xfs_qm_vop_dqalloc touches it even when quotas are disabled.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Felix Blyakher <felixb@sgi.com>
Signed-off-by: Felix Blyakher <felixb@sgi.com>
Kill the quota ops function vector and replace it with direct calls or
stubs in the CONFIG_XFS_QUOTA=n case.
Make sure we check XFS_IS_QUOTA_RUNNING in the right spots. We can remove
the number of those checks because the XFS_TRANS_DQ_DIRTY flag can't be set
otherwise.
This brings us back closer to the way this code worked in IRIX and earlier
Linux versions, but we keep a lot of the more useful factoring of common
code.
Eventually we should also kill xfs_qm_bhv.c, but that's left for a later
patch.
Reduces the size of the source code by about 250 lines and the size of
XFS module by about 1.5 kilobytes with quotas enabled:
text data bss dec hex filename
615957 2960 3848 622765 980ad fs/xfs/xfs.o
617231 3152 3848 624231 98667 fs/xfs/xfs.o.old
Fallout:
- xfs_qm_dqattach is split into xfs_qm_dqattach_locked which expects
the inode locked and xfs_qm_dqattach which does the locking around it,
thus removing XFS_QMOPT_ILOCKED.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Eric Sandeen <sandeen@sandeen.net>
Currently we call from the nicely abstracted linux quotaops into a ugly
multiplexer just to split the calls out at the same boundary again.
Rewrite the quota ops handling to remove that obfucation.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
The XFS_QMOPT_DQLOCK flag introduces major complexity in the quota subsystem
but isn't actually used anywhere. So remove it and all the hazzles it
introduces.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Felix Blyakher <felixb@sgi.com>
Mount options are now parsed by the main XFS module and rejected if quota
support is not available, and there are some new quota operation for the
quotactl syscall and calls to quote in the mount, unmount and sync
callchains.
SGI-PV: 969608
SGI-Modid: xfs-linux-melb:xfs-kern:29503a
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: David Chinner <dgc@sgi.com>
Signed-off-by: Tim Shimmin <tes@sgi.com>
When uquota and oquota (gquota/pquota) are enabled for accounting both are
enforced if ether has enforcement active.
Conditions:
- Both XFS_UQUOTA_ACCT and XFS_GQUOTA_ACCT are enabled.
- Either XFS_UQUOTA_ENFD or XFS_OQUOTA_ENFD is enabled.
- The usage without enforce is reached at the soft limit.
Problems:
1. "repquota" shows all grace time even if no enforcement.
2. we cannot make a file over a hard limits even if no enforcement.
SGI-PV: 962291
SGI-Modid: xfs-linux-melb:xfs-kern:28272a
Signed-off-by: Kouta Ooizumi <k-ooizumi@tnes.nec.co.jp>
Signed-off-by: Donald Douwsma <donaldd@sgi.com>
Signed-off-by: Tim Shimmin <tes@sgi.com>
having previously mounted with quotas.
SGI-PV: 940491
SGI-Modid: xfs-linux:xfs-kern:23388a
Signed-off-by: Tim Shimmin <tes@sgi.com>
Signed-off-by: Nathan Scott <nathans@sgi.com>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!