Commit Graph

27 Commits

Author SHA1 Message Date
Christoph Hellwig
c2adcfa31f xfs: move xfs_rtget_summary to xfs_rtbitmap.c
xfs_rtmodify_summary_int is only used inside xfs_rtbitmap.c and to
implement xfs_rtget_summary.  Move xfs_rtget_summary to xfs_rtbitmap.c
as the exported API and mark xfs_rtmodify_summary_int static.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
2023-12-22 11:18:12 +05:30
Darrick J. Wong
e14293803f xfs: don't allow overly small or large realtime volumes
Don't allow realtime volumes that are less than one rt extent long.
This has been broken across 4 LTS kernels with nobody noticing, so let's
just disable it.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2023-12-06 18:45:17 -08:00
Darrick J. Wong
a6a38f309a xfs: make rextslog computation consistent with mkfs
There's a weird discrepancy in xfsprogs dating back to the creation of
the Linux port -- if there are zero rt extents, mkfs will set
sb_rextents and sb_rextslog both to zero:

	sbp->sb_rextslog =
		(uint8_t)(rtextents ?
			libxfs_highbit32((unsigned int)rtextents) : 0);

However, that's not the check that xfs_repair uses for nonzero rtblocks:

	if (sb->sb_rextslog !=
			libxfs_highbit32((unsigned int)sb->sb_rextents))

The difference here is that xfs_highbit32 returns -1 if its argument is
zero.  Unfortunately, this means that in the weird corner case of a
realtime volume shorter than 1 rt extent, xfs_repair will immediately
flag a freshly formatted filesystem as corrupt.  Because mkfs has been
writing ondisk artifacts like this for decades, we have to accept that
as "correct".  TBH, zero rextslog for zero rtextents makes more sense to
me anyway.

Regrettably, the superblock verifier checks created in commit copied
xfs_repair even though mkfs has been writing out such filesystems for
ages.  Fix the superblock verifier to accept what mkfs spits out; the
userspace version of this patch will have to fix xfs_repair as well.

Note that the new helper leaves the zeroday bug where the upper 32 bits
of sb_rextents is ripped off and fed to highbit32.  This leads to a
seriously undersized rt summary file, which immediately breaks mkfs:

$ hugedisk.sh foo /dev/sdc $(( 0x100000080 * 4096))B
$ /sbin/mkfs.xfs -f /dev/sda -m rmapbt=0,reflink=0 -r rtdev=/dev/mapper/foo
meta-data=/dev/sda               isize=512    agcount=4, agsize=1298176 blks
         =                       sectsz=512   attr=2, projid32bit=1
         =                       crc=1        finobt=1, sparse=1, rmapbt=0
         =                       reflink=0    bigtime=1 inobtcount=1 nrext64=1
data     =                       bsize=4096   blocks=5192704, imaxpct=25
         =                       sunit=0      swidth=0 blks
naming   =version 2              bsize=4096   ascii-ci=0, ftype=1
log      =internal log           bsize=4096   blocks=16384, version=2
         =                       sectsz=512   sunit=0 blks, lazy-count=1
realtime =/dev/mapper/foo        extsz=4096   blocks=4294967424, rtextents=4294967424
Discarding blocks...Done.
mkfs.xfs: Error initializing the realtime space [117 - Structure needs cleaning]

The next patch will drop support for rt volumes with fewer than 1 or
more than 2^32-1 rt extents, since they've clearly been broken forever.

Fixes: f8e566c0f5 ("xfs: validate the realtime geometry in xfs_validate_sb_common")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2023-12-06 18:45:17 -08:00
Darrick J. Wong
e2cf427c91 xfs: simplify rt bitmap/summary block accessor functions
Simplify the calling convention of these functions since the
xfs_rtalloc_args structure contains the parameters we need.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2023-10-19 08:33:42 -07:00
Darrick J. Wong
5b1d0ae975 xfs: simplify xfs_rtbuf_get calling conventions
Now that xfs_rtalloc_args holds references to the last-read bitmap and
summary blocks, we don't need to pass the buffer pointer out of
xfs_rtbuf_get.

Callers no longer have to xfs_trans_brelse on their own, though they are
required to call xfs_rtbuf_cache_relse before the xfs_rtalloc_args goes
out of scope.

While we're at it, create some trivial helpers so that we don't have to
remember if "0" means "bitmap" and "1" means "summary".

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2023-10-19 08:33:40 -07:00
Omar Sandoval
e94b53ff69 xfs: cache last bitmap block in realtime allocator
Profiling a workload on a highly fragmented realtime device showed a ton
of CPU cycles being spent in xfs_trans_read_buf() called by
xfs_rtbuf_get(). Further tracing showed that much of that was repeated
calls to xfs_rtbuf_get() for the same block of the realtime bitmap.
These come from xfs_rtallocate_extent_block(): as it walks through
ranges of free bits in the bitmap, each call to xfs_rtcheck_range() and
xfs_rtfind_{forw,back}() gets the same bitmap block. If the bitmap block
is very fragmented, then this is _a lot_ of buffer lookups.

The realtime allocator already passes around a cache of the last used
realtime summary block to avoid repeated reads (the parameters rbpp and
rsb). We can do the same for the realtime bitmap.

This replaces rbpp and rsb with a struct xfs_rtbuf_cache, which caches
the most recently used block for both the realtime bitmap and summary.
xfs_rtbuf_get() now handles the caching instead of the callers, which
requires plumbing xfs_rtbuf_cache to more functions but also makes sure
we don't miss anything.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2023-10-19 08:22:36 -07:00
Dave Chinner
41f33d82cf xfs: consolidate realtime allocation arguments
Consolidate the arguments passed around the rt allocator into a
struct xfs_rtalloc_arg similar to how the btree allocator arguments
are consolidated in a struct xfs_alloc_arg....

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2023-10-18 16:53:00 -07:00
Darrick J. Wong
663b8db7b0 xfs: use accessor functions for summary info words
Create get and set functions for rtsummary words so that we can redefine
the ondisk format with a specific endianness.  Note that this requires
the definition of a distinct type for ondisk summary info words so that
the compiler can perform proper typechecking.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2023-10-18 16:53:00 -07:00
Darrick J. Wong
bd85af280d xfs: create helpers for rtsummary block/wordcount computations
Create helper functions that compute the number of blocks or words
necessary to store the rt summary file.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2023-10-18 16:53:00 -07:00
Darrick J. Wong
97e993830a xfs: use accessor functions for bitmap words
Create get and set functions for rtbitmap words so that we can redefine
the ondisk format with a specific endianness.  Note that this requires
the definition of a distinct type for ondisk rtbitmap words so that the
compiler can perform proper typechecking as we go back and forth.

In the upcoming rtgroups feature, we're going to fix the problem that
rtwords are written in host endian order, which means we'll need the
distinct rtword/rtword_raw types.

Suggested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2023-10-18 11:46:19 -07:00
Darrick J. Wong
d0448fe76a xfs: create helpers for rtbitmap block/wordcount computations
Create helper functions that compute the number of blocks or words
necessary to store the rt bitmap.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2023-10-18 10:58:58 -07:00
Darrick J. Wong
097b4b7b64 xfs: convert rt summary macros to helpers
Convert the realtime summary file macros to helper functions so that we
can improve type checking.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2023-10-17 17:45:38 -07:00
Darrick J. Wong
a994862684 xfs: convert open-coded xfs_rtword_t pointer accesses to helper
There are a bunch of places where we use open-coded logic to find a
pointer to an xfs_rtword_t within a rt bitmap buffer.  Convert all that
to helper functions for better type safety.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2023-10-17 17:45:38 -07:00
Darrick J. Wong
add3cddaea xfs: remove XFS_BLOCKWSIZE and XFS_BLOCKWMASK macros
Remove these trivial macros since they're not even part of the ondisk
format.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2023-10-17 17:45:37 -07:00
Darrick J. Wong
90d98a6ada xfs: convert the rtbitmap block and bit macros to static inline functions
Replace these macros with typechecked helper functions.  Eventually
we're going to add more logic to the helpers and it'll be easier if we
don't have to macro it up.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2023-10-17 16:26:25 -07:00
Darrick J. Wong
ef5a83b7e5 xfs: use shifting and masking when converting rt extents, if possible
Avoid the costs of integer division (32-bit and 64-bit) if the realtime
extent size is a power of two.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2023-10-17 16:26:25 -07:00
Darrick J. Wong
5f57f7309d xfs: create rt extent rounding helpers for realtime extent blocks
Create a pair of functions to round rtblock numbers up or down to the
nearest rt extent.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2023-10-17 16:26:25 -07:00
Darrick J. Wong
055641248f xfs: convert do_div calls to xfs_rtb_to_rtx helper calls
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>
2023-10-17 16:25:55 -07:00
Darrick J. Wong
5dc3a80d46 xfs: create helpers to convert rt block numbers to rt extent numbers
Create helpers to do unit conversions of rt block numbers to rt extent
numbers.  There are three variations -- one to compute the rt extent
number from an rt block number; one to compute the offset of an rt block
within an rt extent; and one to extract both.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2023-10-17 16:24:22 -07:00
Darrick J. Wong
2c2b981b73 xfs: create a helper to convert extlen to rtextlen
Create a helper to compute the realtime extent (xfs_rtxlen_t) from an
extent length (xfs_extlen_t) value.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2023-10-17 16:24:22 -07:00
Darrick J. Wong
68db60bf01 xfs: create a helper to compute leftovers of realtime extents
Create a helper to compute the misalignment between a file extent
(xfs_extlen_t) and a realtime extent.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2023-10-17 16:24:22 -07:00
Darrick J. Wong
fa5a387230 xfs: create a helper to convert rtextents to rtblocks
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>
2023-10-17 16:24:22 -07:00
Darrick J. Wong
2d5f216b77 xfs: convert rt extent numbers to xfs_rtxnum_t
Further disambiguate the xfs_rtblock_t uses by creating a new type,
xfs_rtxnum_t, to store the position of an extent within the realtime
section, in units of rtextents.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2023-10-17 16:24:22 -07:00
Darrick J. Wong
f29c3e745d xfs: convert rt bitmap extent lengths to xfs_rtbxlen_t
XFS uses xfs_rtblock_t for many different uses, which makes it much more
difficult to perform a unit analysis on the codebase.  One of these
(ab)uses is when we need to store the length of a free space extent as
stored in the realtime bitmap.  Because there can be up to 2^64 realtime
extents in a filesystem, we need a new type that is larger than
xfs_rtxlen_t for callers that are querying the bitmap directly.  This
means scrub and growfs.

Create this type as "xfs_rtbxlen_t" and use it to store 64-bit rtx
lengths.  'b' stands for 'bitmap' or 'big'; reader's choice.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2023-10-17 16:24:22 -07:00
Darrick J. Wong
03f4de332e xfs: convert rt bitmap/summary block numbers to xfs_fileoff_t
We should use xfs_fileoff_t to store the file block offset of any
location within the realtime bitmap or summary files.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2023-10-17 16:24:22 -07:00
Darrick J. Wong
a684c538bc xfs: convert xfs_extlen_t to xfs_rtxlen_t in the rt allocator
In most of the filesystem, we use xfs_extlen_t to store the length of a
file (or AG) space mapping in units of fs blocks.  Unfortunately, the
realtime allocator also uses it to store the length of a rt space
mapping in units of rt extents.  This is confusing, since one rt extent
can consist of many fs blocks.

Separate the two by introducing a new type (xfs_rtxlen_t) to store the
length of a space mapping (in units of realtime extents) that would be
found in a file.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2023-10-17 16:24:22 -07:00
Darrick J. Wong
13928113fc xfs: move the xfs_rtbitmap.c declarations to xfs_rtbitmap.h
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>
2023-10-17 16:24:22 -07:00