Move the pointers to the RT bitmap and summary inodes as well as the
summary cache to the rtgroups structure to prepare for having a
separate bitmap and summary inodes for each rtgroup.
Code using the inodes now needs to operate on a rtgroup. Where easily
possible such code is converted to iterate over all rtgroups, else
rtgroup 0 (the only one that can currently exist) is hardcoded.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Use mp->m_sb.sb_rblocks to calculate the end instead of sb_rextents that
needs a conversion, use consistent names to xfs_rtblock_t types, and
only calculated them by the time they are needed. Remove the pointless
"high" local variable that only has a single user.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Create an incore object that will contain information about a realtime
allocation group. This will eventually enable us to shard the realtime
section in a similar manner to how we shard the data section, but for
now just a single object for the entire RT subvolume is created.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
The calling conventions for xfs_getfsmap_helper are confusing -- callers
pass in an rmap record, but they must also supply startblock and
blockcount in daddr units. This was bolted onto the original fsmap
implementation so that we could report *something* for realtime
volumes, which do not support rmap and hence can draw only from the rt
free space bitmap. Free space on the rt volume can be more than 2^32
fsblocks long, which means that we can't use the rmap startblock or
blockcount fields.
This is confusing for callers, because they must supplying redundant
data, but not all of it is used. Streamline this by creating a separate
fsmap irec structure that contains exactly the data we need, once.
Note that we actually do need rm_startblock for rmap key comparisons
when we're actually querying an rmap btree, so leave that field but
document why it's there.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Replace the pag and rtg pointers with a generic group pointer.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Replace the pag pointers in the type specific union with a generic
xfs_group pointer. This prepares for adding realtime group support.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
The current for_each_perag* macros are a bit annoying in that they
require the caller to both provide an object and an index iterator, and
also somewhat obsfucate the underlying control flow mechanism.
Switch to open coded while loops using new xfs_perag_next{,_from,_range}
helpers that return the next pag structure to iterate on based on the
previous one or NULL for the loop start.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Split the lookup and refcount handling of struct xfs_perag into an
embedded xfs_group structure that can be reused for the upcoming
realtime groups.
It will be extended with more features later.
Note that he xg_type field will only need a single bit even with
realtime group support. For now it fills a hole, but it might be
worth to fold it into another field if we can use this space better.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Add helpers to convert an agbno to a daddr or fsbno based on a pag
structure.
This provides a simpler conversion and better type safety compared to the
existing code that passes the mount structure and the agno separately.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
The for_each_perag helpers update the agno passed in for each iteration,
and thus the "if (pag->pag_agno == start_ag)" check will always be true.
Add another variable for the loop iterator so that the field is only
cleared after the first iteration.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Move this function out of xfs_ioctl.c to reduce the clutter in there,
and make the entire getfsmap implementation self-contained in a single
file.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
The order of the functions in this file has gotten a little confusing
over the years. Specifically, the two data device implementations
(bnobt and rmapbt) could be adjacent in the source code instead of split
in two by the logdev and rtdev fsmap implementations. We're about to
add more functionality to this file, so rearrange things now.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
There isn't much of a good reason to pass the xfs_rtalloc_rec structures
that describe extents to xfs_rtalloc_query_range as we really just want
a lower and upper bound xfs_rtxnum_t. Pass the rtxnum directly and
simply the interface.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
In the fsmap query of xfs, there is an interval missing problem:
[root@fedora ~]# xfs_io -c 'fsmap -vvvv' /mnt
EXT: DEV BLOCK-RANGE OWNER FILE-OFFSET AG AG-OFFSET TOTAL
0: 253:16 [0..7]: static fs metadata 0 (0..7) 8
1: 253:16 [8..23]: per-AG metadata 0 (8..23) 16
2: 253:16 [24..39]: inode btree 0 (24..39) 16
3: 253:16 [40..47]: per-AG metadata 0 (40..47) 8
4: 253:16 [48..55]: refcount btree 0 (48..55) 8
5: 253:16 [56..103]: per-AG metadata 0 (56..103) 48
6: 253:16 [104..127]: free space 0 (104..127) 24
......
BUG:
[root@fedora ~]# xfs_io -c 'fsmap -vvvv -d 104 107' /mnt
[root@fedora ~]#
Normally, we should be able to get [104, 107), but we got nothing.
The problem is caused by shifting. The query for the problem-triggered
scenario is for the missing_owner interval (e.g. freespace in rmapbt/
unknown space in bnobt), which is obtained by subtraction (gap). For this
scenario, the interval is obtained by info->last. However, rec_daddr is
calculated based on the start_block recorded in key[1], which is converted
by calling XFS_BB_TO_FSBT. Then if rec_daddr does not exceed
info->next_daddr, which means keys[1].fmr_physical >> (mp)->m_blkbb_log
<= info->next_daddr, no records will be displayed. In the above example,
104 >> (mp)->m_blkbb_log = 12 and 107 >> (mp)->m_blkbb_log = 12, so the two
are reduced to 0 and the gap is ignored:
before calculate ----------------> after shifting
104(st) 107(ed) 12(st/ed)
|---------| |
sector size block size
Resolve this issue by introducing the "end_daddr" field in
xfs_getfsmap_info. This records |key[1].fmr_physical + key[1].length| at
the granularity of sector. If the current query is the last, the rec_daddr
is end_daddr to prevent missing interval problems caused by shifting. We
only need to focus on the last query, because xfs disks are internally
aligned with disk blocksize that are powers of two and minimum 512, so
there is no problem with shifting in previous queries.
After applying this patch, the above problem have been solved:
[root@fedora ~]# xfs_io -c 'fsmap -vvvv -d 104 107' /mnt
EXT: DEV BLOCK-RANGE OWNER FILE-OFFSET AG AG-OFFSET TOTAL
0: 253:16 [104..106]: free space 0 (104..106) 3
Fixes: e89c041338 ("xfs: implement the GETFSMAP ioctl")
Signed-off-by: Zizhi Wo <wozizhi@huawei.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
[djwong: limit the range of end_addr correctly]
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
Use XFS_BUF_DADDR_NULL (instead of a magic sentinel value) to mean "this
field is null" like the rest of xfs.
Cc: wozizhi@huawei.com
Fixes: e89c041338 ("xfs: implement the GETFSMAP ioctl")
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
I notice a rmap query bug in xfs_io fsmap:
[root@fedora ~]# xfs_io -c 'fsmap -vvvv' /mnt
EXT: DEV BLOCK-RANGE OWNER FILE-OFFSET AG AG-OFFSET TOTAL
0: 253:16 [0..7]: static fs metadata 0 (0..7) 8
1: 253:16 [8..23]: per-AG metadata 0 (8..23) 16
2: 253:16 [24..39]: inode btree 0 (24..39) 16
3: 253:16 [40..47]: per-AG metadata 0 (40..47) 8
4: 253:16 [48..55]: refcount btree 0 (48..55) 8
5: 253:16 [56..103]: per-AG metadata 0 (56..103) 48
6: 253:16 [104..127]: free space 0 (104..127) 24
......
Bug:
[root@fedora ~]# xfs_io -c 'fsmap -vvvv -d 0 3' /mnt
[root@fedora ~]#
Normally, we should be able to get one record, but we got nothing.
The root cause of this problem lies in the incorrect setting of rm_owner in
the rmap query. In the case of the initial query where the owner is not
set, __xfs_getfsmap_datadev() first sets info->high.rm_owner to ULLONG_MAX.
This is done to prevent any omissions when comparing rmap items. However,
if the current ag is detected to be the last one, the function sets info's
high_irec based on the provided key. If high->rm_owner is not specified, it
should continue to be set to ULLONG_MAX; otherwise, there will be issues
with interval omissions. For example, consider "start" and "end" within the
same block. If high->rm_owner == 0, it will be smaller than the founded
record in rmapbt, resulting in a query with no records. The main call stack
is as follows:
xfs_ioc_getfsmap
xfs_getfsmap
xfs_getfsmap_datadev_rmapbt
__xfs_getfsmap_datadev
info->high.rm_owner = ULLONG_MAX
if (pag->pag_agno == end_ag)
xfs_fsmap_owner_to_rmap
// set info->high.rm_owner = 0 because fmr_owner == -1ULL
dest->rm_owner = 0
// get nothing
xfs_getfsmap_datadev_rmapbt_query
The problem can be resolved by simply modify the xfs_fsmap_owner_to_rmap
function internal logic to achieve.
After applying this patch, the above problem have been solved:
[root@fedora ~]# xfs_io -c 'fsmap -vvvv -d 0 3' /mnt
EXT: DEV BLOCK-RANGE OWNER FILE-OFFSET AG AG-OFFSET TOTAL
0: 253:16 [0..7]: static fs metadata 0 (0..7) 8
Fixes: e89c041338 ("xfs: implement the GETFSMAP ioctl")
Signed-off-by: Zizhi Wo <wozizhi@huawei.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
Create helper functions to deal with locking realtime metadata inodes.
This enables us to maintain correct locking order once we start adding
the realtime rmap and refcount btree inodes.
Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
Split xfs_allocbt_init_cursor into separate routines for the by-bno
and by-cnt btrees to prepare for the removal of the xfs_btnum global
enumeration of btree types.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Convert these calls to use the helpers, and clean up all these places
where the same variable can have different units depending on where it
is in the function.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Create a helper to convert a realtime extent to a realtime block. Later
on we'll change the helper to use bit shifts when possible.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Move all the declarations for functionality in xfs_rtbitmap.c into a
separate xfs_rtbitmap.h header file.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Dave Chinner reported that xfs/273 fails if the AG size happens to be an
exact power of two. I traced this to an agbno integer overflow when the
current GETFSMAP call is a continuation of a previous GETFSMAP call, and
the last record returned was non-shareable space at the end of an AG.
__xfs_getfsmap_datadev sets up a data device query by converting the
incoming fmr_physical into an xfs_fsblock_t and cracking it into an agno
and agbno pair. In the (failing) case of where fmr_blockcount of the
low key is nonzero and the record was for a non-shareable extent, it
will add fmr_blockcount to start_fsb and info->low.rm_startblock.
If the low key was actually the last record for that AG, then this
addition causes info->low.rm_startblock to point beyond EOAG. When the
rmapbt range query starts, it'll return an empty set, and fsmap moves on
to the next AG.
Or so I thought. Remember how we added to start_fsb?
If agsize < 1<<agblklog, start_fsb points to the same AG as the original
fmr_physical from the low key. We run the rmapbt query, which returns
nothing, so getfsmap zeroes info->low and moves on to the next AG.
If agsize == 1<<agblklog, start_fsb now points to the next AG. We run
the rmapbt query on the next AG with the excessively large
rm_startblock. If this next AG is actually the last AG, we'll set
info->high to EOFS (which is now has a lower rm_startblock than
info->low), and the ranged btree query code will return -EINVAL. If
it's not the last AG, we ignore all records for the intermediate AGs.
Oops.
Fix this by decoding start_fsb into agno and agbno only after making
adjustments to start_fsb. This means that info->low.rm_startblock will
always be set to a valid agbno, and we always start the rmapbt iteration
in the correct AG.
While we're at it, fix the predicate for determining if an fsmap record
represents non-shareable space to include file data on pre-reflink
filesystems.
Reported-by: Dave Chinner <david@fromorbit.com>
Fixes: 63ef7a3591 ("xfs: fix interval filtering in multi-step fsmap queries")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Improve the validation of the fsmap offset fields in the query keys and
move the validation to the top of the function now that we have pushed
the low key adjustment code downwards.
Also fix some indenting issues that aren't worth a separate patch.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
The external log device fsmap backend doesn't have an rmapbt to query,
so it's wasteful to spend time initializing the rmap_irec objects.
Worse yet, the log could (someday) be longer than 2^32 fsblocks, so
using the rmap irec structure will result in integer overflows.
Fix this mess by computing the start address that we want from keys[0]
directly, and use the daddr-based record filtering algorithm that we
also use for rtbitmap queries.
Fixes: e89c041338 ("xfs: implement the GETFSMAP ioctl")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
The rtbitmap fsmap backend doesn't query the rmapbt, so it's wasteful to
spend time initializing the rmap_irec objects. Worse yet, the logic to
query the rtbitmap is spread across three separate functions, which is
unnecessarily difficult to follow.
Compute the start rtextent that we want from keys[0] directly and
combine the functions to avoid passing parameters around everywhere, and
consolidate all the logic into a single function. At one point many
years ago I intended to use __xfs_getfsmap_rtdev as the launching point
for realtime rmapbt queries, but this hasn't been the case for a long
time.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
The realtime section ends at the last rt extent. If the user configures
the rt geometry with an extent size that is not an integer factor of the
number of rt blocks, it's possible for there to be rt blocks past the
end of the last rt extent. These tail blocks cannot ever be allocated
and will cause corruption reports if the last extent coincides with the
end of an rt bitmap block, so do not report consider them for the
GETFSMAP output.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
It's not correct to use the rmap irec structure to hold query key
information to query the rtbitmap because the realtime volume can be
longer than 2^32 fsblocks in length. Because the rt volume doesn't have
allocation groups, introduce a daddr-based record filtering algorithm
and compute the rtextent values using 64-bit variables. The same
problem exists in the external log device fsmap implementation, so use
the same solution to fix it too.
After this patch, all the code that touches info->low and info->high
under xfs_getfsmap_logdev and __xfs_getfsmap_rtdev are unnecessary.
Cleaning this up will be done in subsequent patches.
Fixes: 4c934c7dd6 ("xfs: report realtime space information via the rtbitmap")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
I noticed a bug in ranged GETFSMAP queries:
# xfs_io -c 'fsmap -vvvv' /opt
EXT: DEV BLOCK-RANGE OWNER FILE-OFFSET AG AG-OFFSET TOTAL
0: 8:80 [0..7]: static fs metadata 0 (0..7) 8
<snip>
9: 8:80 [192..223]: 137 0..31 0 (192..223) 32
# xfs_io -c 'fsmap -vvvv -d 208 208' /opt
#
That's not right -- we asked what block maps block 208, and we should've
received a mapping for inode 137 offset 16. Instead, we get nothing.
The root cause of this problem is a mis-interaction between the fsmap
code and how btree ranged queries work. xfs_btree_query_range returns
any btree record that overlaps with the query interval, even if the
record starts before or ends after the interval. Similarly, GETFSMAP is
supposed to return a recordset containing all records that overlap the
range queried.
However, it's possible that the recordset is larger than the buffer that
the caller provided to convey mappings to userspace. In /that/ case,
userspace is supposed to copy the last record returned to fmh_keys[0]
and call GETFSMAP again. In this case, we do not want to return
mappings that we have already supplied to the caller. The call to
xfs_btree_query_range is the same, but now we ignore any records that
start before fmh_keys[0].
Unfortunately, we didn't implement the filtering predicate correctly.
The predicate should only be called when we're calling back for more
records. Accomplish this by setting info->low.rm_blockcount to a
nonzero value and ensuring that it is cleared as necessary. As a
result, we no longer want to adjust dkeys[0] in the main setup function
because that's confusing.
This patch doesn't touch the logdev/rtbitmap backends because they have
bigger problems that will be addressed by subsequent patches.
Found via xfs/556 with parent pointers enabled.
Fixes: e89c041338 ("xfs: implement the GETFSMAP ioctl")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
If the end position of a GETFSMAP query overlaps an allocated space and
we're using the free space info to generate fsmap info, the akeys
information gets fed into the fsmap formatter with bad results.
Zero-init the space.
Reported-by: syzbot+090ae72d552e6bd93cfe@syzkaller.appspotmail.com
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
We need to be able to dynamically remove instantiated AGs from
memory safely, either for shrinking the filesystem or paging AG
state in and out of memory (e.g. supporting millions of AGs). This
means we need to be able to safely exclude operations from accessing
perags while dynamic removal is in progress.
To do this, introduce the concept of active and passive references.
Active references are required for high level operations that make
use of an AG for a given operation (e.g. allocation) and pin the
perag in memory for the duration of the operation that is operating
on the perag (e.g. transaction scope). This means we can fail to get
an active reference to an AG, hence callers of the new active
reference API must be able to handle lookup failure gracefully.
Passive references are used in low level code, where we might need
to access the perag structure for the purposes of completing high
level operations. For example, buffers need to use passive
references because:
- we need to be able to do metadata IO during operations like grow
and shrink transactions where high level active references to the
AG have already been blocked
- buffers need to pin the perag until they are reclaimed from
memory, something that high level code has no direct control over.
- unused cached buffers should not prevent a shrink from being
started.
Hence we have active references that will form exclusion barriers
for operations to be performed on an AG, and passive references that
will prevent reclaim of the perag until all objects with passive
references have been reclaimed themselves.
This patch introduce xfs_perag_grab()/xfs_perag_rele() as the API
for active AG reference functionality. We also need to convert the
for_each_perag*() iterators to use active references, which will
start the process of converting high level code over to using active
references. Conversion of non-iterator based code to active
references will be done in followup patches.
Note that the implementation using reference counting is really just
a development vehicle for the API to ensure we don't have any leaks
in the callers. Once we need to remove perag structures from memory
dyanmically, we will need a much more robust per-ag state transition
mechanism for preventing new references from being taken while we
wait for existing references to drain before removal from memory can
occur....
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
xfs_rtalloc_query_range scans the realtime bitmap file in order of
increasing file offset, so this caller can take ILOCK_SHARED on the rt
bitmap inode instead of ILOCK_EXCL. This isn't going to yield any
practical benefits at mount time, but we'd like to make the locking
usage consistent around xfs_rtalloc_query_all calls. Make all the
places we do this use the same xfs_ilock lockflags for consistency.
Fixes: 4c934c7dd6 ("xfs: report realtime space information via the rtbitmap")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
xfs_alloc_read_agf() initialises the perag if it hasn't been done
yet, so it makes sense to pass it the perag rather than pull a
reference from the buffer. This allows callers to be per-ag centric
rather than passing mount/agno pairs everywhere.
Whilst modifying the xfs_reflink_find_shared() function definition,
declare it static and remove the extern declaration as it is an
internal function only these days.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Pass an explicit xfs_mount pointer to the rtalloc query functions so
that they can support transactionless queries.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
There are a few places where we test the current process' capability set
to decide if we're going to be more or less generous with resource
acquisition for a system call. If the process doesn't have the
capability, we can continue the call, albeit in a degraded mode.
These are /not/ the actual security decisions, so it's not proper to use
capable(), which (in certain selinux setups) causes audit messages to
get logged. Switch them to has_capability_noaudit.
Fixes: 7317a03df7 ("xfs: refactor inode ownership change transaction/inode/quota allocation idiom")
Fixes: ea9a46e1c4 ("xfs: only return detailed fsmap info if the caller has CAP_SYS_ADMIN")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Cc: Dave Chinner <david@fromorbit.com>
Reviewed-by: Ondrej Mosnacek <omosnace@redhat.com>
Acked-by: Serge Hallyn <serge@hallyn.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Convert the xfs_sb_version_hasfoo() to checks against
mp->m_features. Checks of the superblock itself during disk
operations (e.g. in the read/write verifiers and the to/from disk
formatters) are not converted - they operate purely on the
superblock state. Everything else should use the mount features.
Large parts of this conversion were done with sed with commands like
this:
for f in `git grep -l xfs_sb_version_has fs/xfs/*.c`; do
sed -i -e 's/xfs_sb_version_has\(.*\)(&\(.*\)->m_sb)/xfs_has_\1(\2)/' $f
done
With manual cleanups for things like "xfs_has_extflgbit" and other
little inconsistencies in naming.
The result is ia lot less typing to check features and an XFS binary
size reduced by a bit over 3kB:
$ size -t fs/xfs/built-in.a
text data bss dec hex filenam
before 1130866 311352 484 1442702 16038e (TOTALS)
after 1127727 311352 484 1439563 15f74b (TOTALS)
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
The query_range functions are supposed to call a caller-supplied
function on each record found in the dataset. These functions don't
own the memory storing the record, so don't let them change the record.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
There are several GETFSMAP backend functions for XFS to cover the three
devices and various feature support. Each of these functions are passed
pointers to the low and high keys for the dataset that userspace
requested, and a pointer to scratchpad variables that are used to
control the iteration and fill out records. The scratchpad data can be
changed arbitrarily, but the keys are supposed to remain unchanged (and
under the control of the outermost loop in xfs_getfsmap).
Unfortunately, the data and rt backends modify the keys that are passed
in from the main control loop, which causes subsequent calls to return
incorrect query results. Specifically, each of those two functions set
the block number in the high key to the size of their respective device.
Since fsmap results are sorted in device number order, if the lower
numbered device is smaller than the higher numbered device, the first
function will set the high key to the small size, and the key remains
unchanged as it is passed into the function for the higher numbered
device. The second function will then fail to return all of the results
for the dataset that userspace is asking for because the keyspace is
incorrectly constrained.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
The fsmap implementation for realtime devices uses the gap between
info->next_daddr and a free rtextent reported by xfs_rtalloc_query_range
to feed userspace fsmap records with an "unknown" owner. We use this
trick to report to userspace when the last rtextent in the filesystem is
in use by synthesizing a null rmap record starting at the next block
after the query range.
Unfortunately, there's a minor accounting bug in the way that we
construct the null rmap record. Originally, ahigh.ar_startext contains
the last rtextent for which the user wants records. It's entirely
possible that number is beyond the end of the rt volume, so the location
synthesized rmap record /must/ be constrained to the minimum of the high
key and the number of extents in the rt volume.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
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: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Which will eventually completely replace the agno in it.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Brian 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: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
A recent log refactoring patchset from Brian Foster relaxed fsfreeze
behavior with regards to the buffer cache -- now freeze only waits for
pending buffer IO to finish, and does not try to drain the buffer cache
LRU. As a result, fsfreeze should no longer stall indefinitely while
fsmap runs. Drop the sb_start_write calls around fsmap invocations.
While we're cleaning things, add a comment to the xfs_trans_alloc_empty
call explaining why we're running around with empty transactions.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Refactor xfs_getfsmap to improve its performance: instead of indirectly
calling a function that copies one record to userspace at a time, create
a shadow buffer in the kernel and copy the whole array once at the end.
On the author's computer, this reduces the runtime on his /home by ~20%.
This also eliminates a deadlock when running GETFSMAP against the
realtime device. The current code locks the rtbitmap to create
fsmappings and copies them into userspace, having not released the
rtbitmap lock. If the userspace buffer is an mmap of a sparse file that
itself resides on the realtime device, the write page fault will recurse
into the fs for allocation, which will deadlock on the rtbitmap lock.
Fixes: 4c934c7dd6 ("xfs: report realtime space information via the rtbitmap")
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
If userspace asked fsmap to count the number of entries, we cannot
return more than UINT_MAX entries because fmh_entries is u32.
Therefore, stop counting if we hit this limit or else we will waste time
to return truncated results.
Fixes: e89c041338 ("xfs: implement the GETFSMAP ioctl")
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
I noticed that fsfreeze can take a very long time to freeze an XFS if
there happens to be a GETFSMAP caller running in the background. I also
happened to notice the following in dmesg:
------------[ cut here ]------------
WARNING: CPU: 2 PID: 43492 at fs/xfs/xfs_super.c:853 xfs_quiesce_attr+0x83/0x90 [xfs]
Modules linked in: xfs libcrc32c ip6t_REJECT nf_reject_ipv6 ipt_REJECT nf_reject_ipv4 ip_set_hash_ip ip_set_hash_net xt_tcpudp xt_set ip_set_hash_mac ip_set nfnetlink ip6table_filter ip6_tables bfq iptable_filter sch_fq_codel ip_tables x_tables nfsv4 af_packet [last unloaded: xfs]
CPU: 2 PID: 43492 Comm: xfs_io Not tainted 5.6.0-rc4-djw #rc4
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.10.2-1ubuntu1 04/01/2014
RIP: 0010:xfs_quiesce_attr+0x83/0x90 [xfs]
Code: 7c 07 00 00 85 c0 75 22 48 89 df 5b e9 96 c1 00 00 48 c7 c6 b0 2d 38 a0 48 89 df e8 57 64 ff ff 8b 83 7c 07 00 00 85 c0 74 de <0f> 0b 48 89 df 5b e9 72 c1 00 00 66 90 0f 1f 44 00 00 41 55 41 54
RSP: 0018:ffffc900030f3e28 EFLAGS: 00010202
RAX: 0000000000000001 RBX: ffff88802ac54000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff81e4a6f0 RDI: 00000000ffffffff
RBP: ffff88807859f070 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000010 R12: 0000000000000000
R13: ffff88807859f388 R14: ffff88807859f4b8 R15: ffff88807859f5e8
FS: 00007fad1c6c0fc0(0000) GS:ffff88807e000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0c7d237000 CR3: 0000000077f01003 CR4: 00000000001606a0
Call Trace:
xfs_fs_freeze+0x25/0x40 [xfs]
freeze_super+0xc8/0x180
do_vfs_ioctl+0x70b/0x750
? __fget_files+0x135/0x210
ksys_ioctl+0x3a/0xb0
__x64_sys_ioctl+0x16/0x20
do_syscall_64+0x50/0x1a0
entry_SYSCALL_64_after_hwframe+0x49/0xbe
These two things appear to be related. The assertion trips when another
thread initiates a fsmap request (which uses an empty transaction) after
the freezer waited for m_active_trans to hit zero but before the the
freezer executes the WARN_ON just prior to calling xfs_log_quiesce.
The lengthy delays in freezing happen because the freezer calls
xfs_wait_buftarg to clean out the buffer lru list. Meanwhile, the
GETFSMAP caller is continuing to grab and release buffers, which means
that it can take a very long time for the buffer lru list to empty out.
We fix both of these races by calling sb_start_write to obtain freeze
protection while using empty transactions for GETFSMAP and for metadata
scrubbing. The other two users occur during mount, during which time we
cannot fs freeze.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
bc_private.a -> bc_ag conversion via script:
`sed -i 's/bc_private\.a/bc_ag/g' fs/xfs/*[ch] fs/xfs/*/*[ch]`
And then revert the change to the bc_ag #define in
fs/xfs/libxfs/xfs_btree.h manually.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
The fsmap handler shouldn't fail silently if the rmap code ever feeds it
a special owner number that isn't known to the fsmap handler.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
