The struct xfs_buf_log_format wants to think the dirty bitmap is
variable sized.  In fact, it is variable size on disk simply due to
the way we map it from the in-memory structure, but we still just
use a fixed size memory allocation for the in-memory structure.

Hence it makes no sense to set the function up as a variable sized
structure when we already know it's maximum size, and we always
allocate it as such. Simplify the structure by making the dirty
bitmap a fixed sized array and just using the size of the structure
for the allocation size.

This will make it much simpler to allocate and manipulate an array
of format structures for discontiguous buffer support.

The previous struct xfs_buf_log_item size according to
/proc/slabinfo was 224 bytes. pahole doesn't give the same size
because of the variable size definition. With this modification,
pahole reports the same as /proc/slabinfo:

	/* size: 224, cachelines: 4, members: 6 */

Because the xfs_buf_log_item size is now determined by the maximum
supported block size we introduce a dependency on xfs_alloc_btree.h.
Avoid this dependency by moving the idefines for the maximum block
sizes supported to xfs_types.h with all the other max/min type
defines to avoid any new dependencies.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NBen Myers <bpm@sgi.com>

structures.

Always use the generic xfs_btree_block type instead of the short / long
structures. Add XFS_BTREE_SBLOCK_LEN / XFS_BTREE_LBLOCK_LEN defines for
the length of a short / long form block. The rationale for this is that we
will grow more btree block header variants to support CRCs and other RAS
information, and always accessing them through the same datatype with
unions for the short / long form pointers makes implementing this much
easier.

SGI-PV: 988146

SGI-Modid: xfs-linux-melb:xfs-kern:32300a
Signed-off-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NDonald Douwsma <donaldd@sgi.com>
Signed-off-by: NDavid Chinner <david@fromorbit.com>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>

Replace the generic record / key / ptr addressing macros that use cpp
token pasting with simpler macros that do the job for just one given btree
type. The new macros lose the cur argument and thus can be used outside
the core btree code, but also gain an xfs_mount * argument to allow for
checking the CRC flag in the near future. Note that many of these macros
aren't actually used in the kernel code, but only in userspace (mostly in
xfs_repair).

SGI-PV: 988146

SGI-Modid: xfs-linux-melb:xfs-kern:32295a
Signed-off-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NDonald Douwsma <donaldd@sgi.com>
Signed-off-by: NDavid Chinner <david@fromorbit.com>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>

Clean up the way the maximum and minimum records for the btree blocks are
calculated. For the alloc and inobt btrees all the values are
pre-calculated in xfs_mount_common, and we switch the current loop around
the ugly generic macros that use cpp token pasting to generate type names
to two small helpers in normal C code. For the bmbt and bmdr trees these
helpers also exist, but can be called during runtime, too. Here we also
kill various macros dealing with them and inline the logic into the
get_minrecs / get_maxrecs / get_dmaxrecs methods in xfs_bmap_btree.c.

Note that all these new helpers take an xfs_mount * argument which will be
needed to determine the size of a btree block once we add support for
extended btree blocks with CRCs and other RAS information.

SGI-PV: 988146

SGI-Modid: xfs-linux-melb:xfs-kern:32292a
Signed-off-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NDonald Douwsma <donaldd@sgi.com>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>

Not really much reason to make it generic given that it's so small, but
this is the last non-method in xfs_alloc_btree.c and xfs_ialloc_btree.c,
so it makes the whole btree implementation more structured.

SGI-PV: 985583

SGI-Modid: xfs-linux-melb:xfs-kern:32206a
Signed-off-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>
Signed-off-by: NBill O'Donnell <billodo@sgi.com>
Signed-off-by: NDavid Chinner <david@fromorbit.com>

Make the btree delete code generic. Based on a patch from David Chinner
with lots of changes to follow the original btree implementations more
closely. While this loses some of the generic helper routines for
inserting/moving/removing records it also solves some of the one off bugs
in the original code and makes it easier to verify.

SGI-PV: 985583

SGI-Modid: xfs-linux-melb:xfs-kern:32205a
Signed-off-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>
Signed-off-by: NBill O'Donnell <billodo@sgi.com>
Signed-off-by: NDavid Chinner <david@fromorbit.com>

Make the btree insert code generic. Based on a patch from David Chinner
with lots of changes to follow the original btree implementations more
closely. While this loses some of the generic helper routines for
inserting/moving/removing records it also solves some of the one off bugs
in the original code and makes it easier to verify.

SGI-PV: 985583

SGI-Modid: xfs-linux-melb:xfs-kern:32202a
Signed-off-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>
Signed-off-by: NBill O'Donnell <billodo@sgi.com>
Signed-off-by: NDavid Chinner <david@fromorbit.com>

From: Dave Chinner <dgc@sgi.com>

The most complicated part here is the lastrec tracking for the alloc
btree. Most logic is in the update_lastrec method which has to do some
hopefully good enough dirty magic to maintain it.

[hch: split out from bigger patch and a rework of the lastrec

logic]

SGI-PV: 985583

SGI-Modid: xfs-linux-melb:xfs-kern:32194a
Signed-off-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>
Signed-off-by: NBill O'Donnell <billodo@sgi.com>
Signed-off-by: NDavid Chinner <david@fromorbit.com>

From: Dave Chinner <dgc@sgi.com>

[hch: split out from bigger patch and minor adaptions]

SGI-PV: 985583

SGI-Modid: xfs-linux-melb:xfs-kern:32192a
Signed-off-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>
Signed-off-by: NBill O'Donnell <billodo@sgi.com>
Signed-off-by: NDavid Chinner <david@fromorbit.com>

From: Dave Chinner <dgc@sgi.com>

[hch: split out from bigger patch and minor adaptions]

SGI-PV: 985583

SGI-Modid: xfs-linux-melb:xfs-kern:32191a
Signed-off-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>
Signed-off-by: NBill O'Donnell <billodo@sgi.com>
Signed-off-by: NDavid Chinner <david@fromorbit.com>

From: Dave Chinner <dgc@sgi.com>

Because this is the first major generic btree routine this patch includes
some infrastrucure, first a few routines to deal with a btree block that
can be either in short or long form, second xfs_btree_read_buf_block,
which is the new central routine to read a btree block given a cursor, and
third the new xfs_btree_ptr_addr routine to calculate the address for a
given btree pointer record.

[hch: split out from bigger patch and minor adaptions]

SGI-PV: 985583

SGI-Modid: xfs-linux-melb:xfs-kern:32190a
Signed-off-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>
Signed-off-by: NBill O'Donnell <billodo@sgi.com>
Signed-off-by: NDavid Chinner <david@fromorbit.com>

xfs_btree_init_cursor contains close to little shared code for the
different btrees and will get even more non-common code in the future.
Split it up into one routine per btree type.

Because xfs_btree_dup_cursor needs to call the init routine for a generic
btree cursor add a new btree operation vector that contains a dup_cursor
method that initializes a new cursor based on an existing one.

The btree operations vector is based on an idea and code from Dave Chinner
and will grow more entries later during this series.

SGI-PV: 985583

SGI-Modid: xfs-linux-melb:xfs-kern:32176a
Signed-off-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>
Signed-off-by: NBill O'Donnell <billodo@sgi.com>
Signed-off-by: NDavid Chinner <david@fromorbit.com>

It makes it incrementally clearer to read the code when the top of a macro
spaghetti-pile only receives the 3 arguments it uses, rather than 2 extra
ones which are not used. Also when you start pulling this thread out of
the sweater (i.e. remove unused args from XFS_BTREE_*_ADDR), a couple
other third arms etc fall off too. If they're not used in the macro, then
they sometimes don't need to be passed to the function calling the macro
either, etc....

Patch provided by Eric Sandeen (sandeen@sandeen.net).

SGI-PV: 960197
SGI-Modid: xfs-linux-melb:xfs-kern:28037a
Signed-off-by: NEric Sandeen <sandeen@sandeen.net>
Signed-off-by: NDavid Chinner <dgc@sgi.com>
Signed-off-by: NTim Shimmin <tes@sgi.com>

SGI-PV: 943272
SGI-Modid: xfs-linux:xfs-kern:201006a
Signed-off-by: NChristoph Hellwig <hch@sgi.com>
Signed-off-by: NNathan Scott <nathans@sgi.com>

boilerplate.

SGI-PV: 913862
SGI-Modid: xfs-linux:xfs-kern:23903a
Signed-off-by: NNathan Scott <nathans@sgi.com>

SGI-PV: 943122
SGI-Modid: xfs-linux:xfs-kern:23901a
Signed-off-by: NNathan 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!