The only caller of xfs_dialloc_select_ag() will always return
-ENOSPC to it's caller if the agbp returned from
xfs_dialloc_select_ag() is NULL. IOWs, failure to find a candidate
AGI we can allocate inodes from is always an ENOSPC condition, so
move this logic up into xfs_dialloc_select_ag() so we can simplify
the return logic in this function.

xfs_dialloc_select_ag() now only ever returns 0 with a locked
agbp, or an error with no agbp.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NDarrick J. Wong <djwong@kernel.org>

Now that everything passes a perag, the agno is not needed anymore.
Convert all the users to use pag->pag_agno instead and remove the
agno from the cursor. This was largely done as an automated search
and replace.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NDarrick J. Wong <djwong@kernel.org>

Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NDarrick J. Wong <djwong@kernel.org>

Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NDarrick J. Wong <djwong@kernel.org>

Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NDarrick J. Wong <djwong@kernel.org>

Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NDarrick J. Wong <djwong@kernel.org>

Which will eventually completely replace the agno in it.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NDarrick J. Wong <djwong@kernel.org>
Reviewed-by: NBrian Foster <bfoster@redhat.com>

Needs a [from, to] ranged AG walk, and the perag to be stuffed into
the info structure for callouts to use.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NDarrick J. Wong <djwong@kernel.org>

We currently pass an agno from the AG reservation functions to the
individual feature accounting functions, which in future may have to
do perag lookups to access per-AG state. Instead, pre-emptively
plumb the perag through from the highest AG reservation layer to the
feature callouts so they won't have to look it up again.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NDarrick J. Wong <djwong@kernel.org>
Reviewed-by: NBrian Foster <bfoster@redhat.com>

All of the callers of the busy extent API either have perag
references available to use so we can pass a perag to the busy
extent functions rather than having them have to do unnecessary
lookups.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NDarrick J. Wong <djwong@kernel.org>

Clean up the last external manual AG walk.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NDarrick J. Wong <djwong@kernel.org>

Rather than manually walking the ags and passing agnunbers around,
pass the perag for the AG we are currently working on around in the
iwalk structure.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NDarrick J. Wong <djwong@kernel.org>

Convert the raw walks to an iterator, pulling the current AG out of
pag->pag_agno instead of the loop iterator variable.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NDarrick J. Wong <djwong@kernel.org>

for_each_perag_tag() is defined in xfs_icache.c for local use.
Promote this to xfs_ag.h and define equivalent iteration functions
so that we can use them to iterate AGs instead to replace open coded
perag walks and perag lookups.

We also convert as many of the straight forward open coded AG walks
to use these iterators as possible. Anything that is not a direct
conversion to an iterator is ignored and will be updated in future
commits.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NDarrick J. Wong <djwong@kernel.org>

Move the xfs_perag infrastructure to the libxfs files that contain
all the per AG infrastructure. This helps set up for passing perags
around all the code instead of bare agnos with minimal extra
includes for existing files.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NDarrick J. Wong <djwong@kernel.org>

They are AG functions, not superblock functions, so move them to the
appropriate location.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NDarrick J. Wong <djwong@kernel.org>

Introduce an in-core counter to track the sum of all allocbt blocks
used by the filesystem. This value is currently tracked per-ag via
the ->agf_btreeblks field in the AGF, which also happens to include
rmapbt blocks. A global, in-core count of allocbt blocks is required
to identify the subset of global ->m_fdblocks that consists of
unavailable blocks currently used for allocation btrees. To support
this calculation at block reservation time, construct a similar
global counter for allocbt blocks, populate it on first read of each
AGF and update it as allocbt blocks are used and released.
Signed-off-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NChandan Babu R <chandanrlinux@gmail.com>
Reviewed-by: NAllison Henderson <allison.henderson@oracle.com>
Reviewed-by: NDarrick J. Wong <djwong@kernel.org>
Signed-off-by: NDarrick J. Wong <djwong@kernel.org>

perag reservation is enabled at mount time on a per AG basis. The
upcoming change to set aside allocbt blocks from block reservation
requires a populated allocbt counter as soon as possible after mount
to be fully effective against large perag reservations. Therefore as
a preparation step, initialize the pagf on all mounts where at least
one reservation is active. Note that this already occurs to some
degree on most default format filesystems as reservation requirement
calculations already depend on the AGF or AGI, depending on the
reservation type.
Signed-off-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NChandan Babu R <chandanrlinux@gmail.com>
Reviewed-by: NAllison Henderson <allison.henderson@oracle.com>
Reviewed-by: NDarrick J. Wong <djwong@kernel.org>
Signed-off-by: NDarrick J. Wong <djwong@kernel.org>

Keep the mount superblock counters up to date for !lazysbcount
filesystems so that when we log the superblock they do not need
updating in any way because they are already correct.

It's found by what Zorro reported:
1. mkfs.xfs -f -l lazy-count=0 -m crc=0 $dev
2. mount $dev $mnt
3. fsstress -d $mnt -p 100 -n 1000 (maybe need more or less io load)
4. umount $mnt
5. xfs_repair -n $dev
and I've seen no problem with this patch.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reported-by: NZorro Lang <zlang@redhat.com>
Reviewed-by: NGao Xiang <hsiangkao@redhat.com>
Signed-off-by: NGao Xiang <hsiangkao@redhat.com>
Reviewed-by: NDarrick J. Wong <djwong@kernel.org>
Signed-off-by: NDarrick J. Wong <djwong@kernel.org>
Reviewed-by: NBrian Foster <bfoster@redhat.com>

In commit f8f2835a we changed the behavior of XFS to use EFIs to
remove blocks from an overfilled AGFL because there were complaints
about transaction overruns that stemmed from trying to free multiple
blocks in a single transaction.

Unfortunately, that commit missed a subtlety in the debug-mode
transaction accounting when a realtime volume is attached.  If a
realtime file undergoes a data fork mapping change such that realtime
extents are allocated (or freed) in the same transaction that a data
device block is also allocated (or freed), we can trip a debugging
assertion.  This can happen (for example) if a realtime extent is
allocated and it is necessary to reshape the bmbt to hold the new
mapping.

When we go to allocate a bmbt block from an AG, the first thing the data
device block allocator does is ensure that the freelist is the proper
length.  If the freelist is too long, it will trim the freelist to the
proper length.

In debug mode, trimming the freelist calls xfs_trans_agflist_delta() to
record the decrement in the AG free list count.  Prior to f8f28 we would
put the free block back in the free space btrees in the same
transaction, which calls xfs_trans_agblocks_delta() to record the
increment in the AG free block count.  Since AGFL blocks are included in
the global free block count (fdblocks), there is no corresponding
fdblocks update, so the AGFL free satisfies the following condition in
xfs_trans_apply_sb_deltas:

	/*
	 * Check that superblock mods match the mods made to AGF counters.
	 */
	ASSERT((tp->t_fdblocks_delta + tp->t_res_fdblocks_delta) ==
	       (tp->t_ag_freeblks_delta + tp->t_ag_flist_delta +
		tp->t_ag_btree_delta));

The comparison here used to be: (X + 0) == ((X+1) + -1 + 0), where X is
the number blocks that were allocated.

After commit f8f28 we defer the block freeing to the next chained
transaction, which means that the calls to xfs_trans_agflist_delta and
xfs_trans_agblocks_delta occur in separate transactions.  The (first)
transaction that shortens the free list trips on the comparison, which
has now become:

(X + 0) == ((X) + -1 + 0)

because we haven't freed the AGFL block yet; we've only logged an
intention to free it.  When the second transaction (the deferred free)
commits, it will evaluate the expression as:

(0 + 0) == (1 + 0 + 0)

and trip over that in turn.

At this point, the astute reader may note that the two commits tagged by
this patch have been in the kernel for a long time but haven't generated
any bug reports.  How is it that the author became aware of this bug?

This originally surfaced as an intermittent failure when I was testing
realtime rmap, but a different bug report by Zorro Lang reveals the same
assertion occuring on !lazysbcount filesystems.

The common factor to both reports (and why this problem wasn't
previously reported) becomes apparent if we consider when
xfs_trans_apply_sb_deltas is called by __xfs_trans_commit():

	if (tp->t_flags & XFS_TRANS_SB_DIRTY)
		xfs_trans_apply_sb_deltas(tp);

With a modern lazysbcount filesystem, transactions update only the
percpu counters, so they don't need to set XFS_TRANS_SB_DIRTY, hence
xfs_trans_apply_sb_deltas is rarely called.

However, updates to the count of free realtime extents are not part of
lazysbcount, so XFS_TRANS_SB_DIRTY will be set on transactions adding or
removing data fork mappings to realtime files; similarly,
XFS_TRANS_SB_DIRTY is always set on !lazysbcount filesystems.

Dave mentioned in response to an earlier version of this patch:

"IIUC, what you are saying is that this debug code is simply not
exercised in normal testing and hasn't been for the past decade?  And it
still won't be exercised on anything other than realtime device testing?

"...it was debugging code from 1994 that was largely turned into dead
code when lazysbcounters were introduced in 2007. Hence I'm not sure it
holds any value anymore."

This debugging code isn't especially helpful - you can modify the
flcount on one AG and the freeblks of another AG, and it won't trigger.
Add the fact that nobody noticed for a decade, and let's just get rid of
it (and start testing realtime :P).

This bug was found by running generic/051 on either a V4 filesystem
lacking lazysbcount; or a V5 filesystem with a realtime volume.

Cc: bfoster@redhat.com, zlang@redhat.com
Fixes: f8f2835a ("xfs: defer agfl block frees when dfops is available")
Signed-off-by: NDarrick J. Wong <djwong@kernel.org>
Reviewed-by: NBrian Foster <bfoster@redhat.com>

Rename struct xfs_legacy_ictimestamp to struct xfs_log_legacy_timestamp
as it is a type used for logging timestamps with no relationship to the
in-core inode.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDarrick J. Wong <djwong@kernel.org>
Signed-off-by: NDarrick J. Wong <djwong@kernel.org>

Rename xfs_ictimestamp_t to xfs_log_timestamp_t as it is a type used
for logging timestamps with no relationship to the in-core inode.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDarrick J. Wong <djwong@kernel.org>
Signed-off-by: NDarrick J. Wong <djwong@kernel.org>

The in-memory XFS_IFEXTENTS is now only used to check if an inode with
extents still needs the extents to be read into memory before doing
operations that need the extent map.  Add a new xfs_need_iread_extents
helper that returns true for btree format forks that do not have any
entries in the in-memory extent btree, and use that instead of checking
the XFS_IFEXTENTS flag.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDarrick J. Wong <djwong@kernel.org>
Signed-off-by: NDarrick J. Wong <djwong@kernel.org>

Just check for an inline format fork instead of the using the equivalent
in-memory XFS_IFINLINE flag.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDarrick J. Wong <djwong@kernel.org>
Signed-off-by: NDarrick J. Wong <djwong@kernel.org>

Just check for a btree format fork instead of the using the equivalent
in-memory XFS_IFBROOT flag.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDarrick J. Wong <djwong@kernel.org>
Signed-off-by: NDarrick J. Wong <djwong@kernel.org>

Stop using the XFS_IFEXTENTS flag, and instead switch on the fork format
in xfs_idestroy_fork to decide how to cleanup.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NDarrick J. Wong <djwong@kernel.org>
Signed-off-by: NDarrick J. Wong <djwong@kernel.org>

Directly return from the subfunctions and avoid the error variable.  Also
remove the not really needed dp local variable.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NDarrick J. Wong <djwong@kernel.org>
Signed-off-by: NDarrick J. Wong <djwong@kernel.org>

xfs_bmap_one_block is only called for the attribute fork.  Move it to
xfs_attr.c, drop the unused whichfork argument and code only executed for
the data fork and rename the result to xfs_attr_is_leaf.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NDarrick J. Wong <djwong@kernel.org>
Signed-off-by: NDarrick J. Wong <djwong@kernel.org>

Move the XFS_IFEXTENTS check from the callers into xfs_iread_extents to
simplify the code.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NDarrick J. Wong <djwong@kernel.org>
Signed-off-by: NDarrick J. Wong <djwong@kernel.org>

Use the fileattr API to let the VFS handle locking, permission checking and
conversion.
Signed-off-by: NMiklos Szeredi <mszeredi@redhat.com>
Cc: Darrick J. Wong <djwong@kernel.org>

A previous commit removed a call to xfs_attr3_leaf_read that
assigned an error return code to variable error. We now have
a few early error return paths to label 'out' that return
error if error is set; however error now is uninitialized
so potentially garbage is being returned.  Fix this by setting
error to zero to restore the original behaviour where error
was zero at the label 'restart'.

Addresses-Coverity: ("Uninitialized scalar variable")
Fixes: 07120f1a ("xfs: Add xfs_has_attr and subroutines")
Signed-off-by: NColin Ian King <colin.king@canonical.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NDarrick J. Wong <djwong@kernel.org>
Signed-off-by: NDarrick J. Wong <djwong@kernel.org>

Default attr fork offset is based on inode size, so is a fixed
geometry parameter of the inode. Move it to the xfs_ino_geometry
structure and stop calculating it on every call to
xfs_default_attroffset().
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Tested-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDarrick J. Wong <djwong@kernel.org>
Signed-off-by: NDarrick J. Wong <djwong@kernel.org>
Reviewed-by: NAllison Henderson <allison.henderson@oracle.com>

Device inodes have a non-default data fork size of 8 bytes
as checked/enforced by xfs_repair. xfs_default_attroffset() doesn't
handle this, so lets do a minor refactor so it does.

Fixes: e6a688c3 ("xfs: initialise attr fork on inode create")
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Tested-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NDarrick J. Wong <djwong@kernel.org>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NDarrick J. Wong <djwong@kernel.org>
Reviewed-by: NAllison Henderson <allison.henderson@oracle.com>

The incore data fork of an inode stores the bmap btree root node as 'struct
xfs_btree_block'. However, the ondisk version of the inode stores the bmap
btree root node as a 'struct xfs_bmdr_block'.

xfs_bmap_add_attrfork_btree() checks if the btree root node fits inside the
data fork of the inode. However, it incorrectly uses 'struct xfs_btree_block'
to compute the size of the bmap btree root node. Since size of 'struct
xfs_btree_block' is larger than that of 'struct xfs_bmdr_block',
xfs_bmap_add_attrfork_btree() could end up unnecessarily demoting the current
root node as the child of newly allocated root node.

This commit optimizes space usage by modifying xfs_bmap_add_attrfork_btree()
to use 'struct xfs_bmdr_block' to check if the bmap btree root node fits
inside the data fork of the inode.
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NChandan Babu R <chandanrlinux@gmail.com>
Reviewed-by: NDarrick J. Wong <djwong@kernel.org>
Signed-off-by: NDarrick J. Wong <djwong@kernel.org>

Use of the flag has had no effect since kernel commit 288699fe
("xfs: drop dmapi hooks"), which removed all dmapi related code, so
deprecate it.
Signed-off-by: NAnthony Iliopoulos <ailiop@suse.com>
Reviewed-by: NDarrick J. Wong <djwong@kernel.org>
Signed-off-by: NDarrick J. Wong <djwong@kernel.org>

Move the crtime field from struct xfs_icdinode into stuct xfs_inode and
remove the now entirely unused struct xfs_icdinode.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDarrick J. Wong <djwong@kernel.org>
Signed-off-by: NDarrick J. Wong <djwong@kernel.org>

In preparation of removing the historic icinode struct, move the flags2
field into the containing xfs_inode structure.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDarrick J. Wong <djwong@kernel.org>
Signed-off-by: NDarrick J. Wong <djwong@kernel.org>

In preparation of removing the historic icinode struct, move the flags
field into the containing xfs_inode structure.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDarrick J. Wong <djwong@kernel.org>
Signed-off-by: NDarrick J. Wong <djwong@kernel.org>

In preparation of removing the historic icinode struct, move the
forkoff field into the containing xfs_inode structure.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDarrick J. Wong <djwong@kernel.org>
Signed-off-by: NDarrick J. Wong <djwong@kernel.org>

The i_cowextsize field is only used for v3 inodes, and the i_flushiter
field is only used for v1/v2 inodes.  Use a union to pack the inode a
littler better after adding a few missing guards around their usage.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDarrick J. Wong <djwong@kernel.org>
Signed-off-by: NDarrick J. Wong <djwong@kernel.org>