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2021-03-25xfs: prevent metadata files from being inactivatedDarrick J. Wong1-1/+1
Files containing metadata (quota records, rt bitmap and summary info) are fully managed by the filesystem, which means that all resource cleanup must be explicit, not automatic. This means that they should never be subjected automatic to post-eof truncation, nor should they be freed automatically even if the link count drops to zero. In other words, xfs_inactive() should leave these files alone. Add the necessary predicate functions to make this happen. This adds a second layer of prevention for the kinds of fs corruption that was fixed by commit f4c32e87de7d. If we ever decide to support removing metadata files, we should make all those metadata updates explicit. Rearrange the order of #includes to fix compiler errors, since xfs_mount.h is supposed to be included before xfs_inode.h Followup-to: f4c32e87de7d ("xfs: fix realtime bitmap/summary file truncation when growing rt volume") Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de>
2020-09-06xfs: remove kmem_realloc()Carlos Maiolino1-1/+1
Remove kmem_realloc() function and convert its users to use MM API directly (krealloc()) Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2019-10-21xfs: fix inode fork extent count overflowDave Chinner1-1/+1
[commit message is verbose for discussion purposes - will trim it down later. Some questions about implementation details at the end.] Zorro Lang recently ran a new test to stress single inode extent counts now that they are no longer limited by memory allocation. The test was simply: # xfs_io -f -c "falloc 0 40t" /mnt/scratch/big-file # ~/src/xfstests-dev/punch-alternating /mnt/scratch/big-file This test uncovered a problem where the hole punching operation appeared to finish with no error, but apparently only created 268M extents instead of the 10 billion it was supposed to. Further, trying to punch out extents that should have been present resulted in success, but no change in the extent count. It looked like a silent failure. While running the test and observing the behaviour in real time, I observed the extent coutn growing at ~2M extents/minute, and saw this after about an hour: # xfs_io -f -c "stat" /mnt/scratch/big-file |grep next ; \ > sleep 60 ; \ > xfs_io -f -c "stat" /mnt/scratch/big-file |grep next fsxattr.nextents = 127657993 fsxattr.nextents = 129683339 # And a few minutes later this: # xfs_io -f -c "stat" /mnt/scratch/big-file |grep next fsxattr.nextents = 4177861124 # Ah, what? Where did that 4 billion extra extents suddenly come from? Stop the workload, unmount, mount: # xfs_io -f -c "stat" /mnt/scratch/big-file |grep next fsxattr.nextents = 166044375 # And it's back at the expected number. i.e. the extent count is correct on disk, but it's screwed up in memory. I loaded up the extent list, and immediately: # xfs_io -f -c "stat" /mnt/scratch/big-file |grep next fsxattr.nextents = 4192576215 # It's bad again. So, where does that number come from? xfs_fill_fsxattr(): if (ip->i_df.if_flags & XFS_IFEXTENTS) fa->fsx_nextents = xfs_iext_count(&ip->i_df); else fa->fsx_nextents = ip->i_d.di_nextents; And that's the behaviour I just saw in a nutshell. The on disk count is correct, but once the tree is loaded into memory, it goes whacky. Clearly there's something wrong with xfs_iext_count(): inline xfs_extnum_t xfs_iext_count(struct xfs_ifork *ifp) { return ifp->if_bytes / sizeof(struct xfs_iext_rec); } Simple enough, but 134M extents is 2**27, and that's right about where things went wrong. A struct xfs_iext_rec is 16 bytes in size, which means 2**27 * 2**4 = 2**31 and we're right on target for an integer overflow. And, sure enough: struct xfs_ifork { int if_bytes; /* bytes in if_u1 */ .... Once we get 2**27 extents in a file, we overflow if_bytes and the in-core extent count goes wrong. And when we reach 2**28 extents, if_bytes wraps back to zero and things really start to go wrong there. This is where the silent failure comes from - only the first 2**28 extents can be looked up directly due to the overflow, all the extents above this index wrap back to somewhere in the first 2**28 extents. Hence with a regular pattern, trying to punch a hole in the range that didn't have holes mapped to a hole in the first 2**28 extents and so "succeeded" without changing anything. Hence "silent failure"... Fix this by converting if_bytes to a int64_t and converting all the index variables and size calculations to use int64_t types to avoid overflows in future. Signed integers are still used to enable easy detection of extent count underflows. This enables scalability of extent counts to the limits of the on-disk format - MAXEXTNUM (2**31) extents. Current testing is at over 500M extents and still going: fsxattr.nextents = 517310478 Reported-by: Zorro Lang <zlang@redhat.com> 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>
2019-08-28xfs: remove unnecessary parameter from xfs_iext_inc_seqDarrick J. Wong1-4/+4
This function doesn't use the @state parameter, so get rid of it. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2019-06-28xfs: remove unused header filesEric Sandeen1-5/+0
There are many, many xfs header files which are included but unneeded (or included twice) in the xfs code, so remove them. nb: xfs_linux.h includes about 9 headers for everyone, so those explicit includes get removed by this. I'm not sure what the preference is, but if we wanted explicit includes everywhere, a followup patch could remove those xfs_*.h includes from xfs_linux.h and move them into the files that need them. Or it could be left as-is. Signed-off-by: Eric Sandeen <sandeen@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2019-06-28xfs: move xfs_ino_geometry to xfs_shared.hDarrick J. Wong1-0/+1
The inode geometry structure isn't related to ondisk format; it's support for the mount structure. Move it to xfs_shared.h. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2019-02-11xfs: update fork seq counter on data fork changesBrian Foster1-7/+6
The sequence counter in the xfs_ifork structure is only updated on COW forks. This is because the counter is currently only used to optimize out repetitive COW fork checks at writeback time. Tweak the extent code to update the seq counter regardless of the fork type in preparation for using this counter on data forks as well. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Allison Henderson <allison.henderson@oracle.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-08-07xfs: use WRITE_ONCE to update if_seqChristoph Hellwig1-3/+17
This adds ordering of the updates and makes sure we always see the if_seq update before the extent tree is modified. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-07-31xfs: maintain a sequence count for inode fork manipulationsChristoph Hellwig1-0/+6
Add a simple 32-bit unsigned integer as the sequence count for modifications to the extent list in the inode fork. This will be used to optimize away extent list lookups in the writeback code. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-06-06xfs: convert to SPDX license tagsDave Chinner1-9/+1
Remove the verbose license text from XFS files and replace them with SPDX tags. This does not change the license of any of the code, merely refers to the common, up-to-date license files in LICENSES/ This change was mostly scripted. fs/xfs/Makefile and fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected and modified by the following command: for f in `git grep -l "GNU General" fs/xfs/` ; do echo $f cat $f | awk -f hdr.awk > $f.new mv -f $f.new $f done And the hdr.awk script that did the modification (including detecting the difference between GPL-2.0 and GPL-2.0+ licenses) is as follows: $ cat hdr.awk BEGIN { hdr = 1.0 tag = "GPL-2.0" str = "" } /^ \* This program is free software/ { hdr = 2.0; next } /any later version./ { tag = "GPL-2.0+" next } /^ \*\// { if (hdr > 0.0) { print "// SPDX-License-Identifier: " tag print str print $0 str="" hdr = 0.0 next } print $0 next } /^ \* / { if (hdr > 1.0) next if (hdr > 0.0) { if (str != "") str = str "\n" str = str $0 next } print $0 next } /^ \*/ { if (hdr > 0.0) next print $0 next } // { if (hdr > 0.0) { if (str != "") str = str "\n" str = str $0 next } print $0 } END { } $ 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>
2017-12-14xfs: move xfs_iext_insert tracepoint to report useful informationDarrick J. Wong1-2/+2
Move the tracepoint in xfs_iext_insert to after the point where we've inserted the extent because otherwise we report stale extent data in the ftrace output. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2017-11-21xfs: fix memory leak in xfs_iext_free_last_leafShu Wang1-1/+1
found the issue by kmemleak. unreferenced object 0xffff8800674611c0 (size 16): xfs_iext_insert+0x82a/0xa90 [xfs] xfs_bmap_add_extent_hole_delay+0x1e5/0x5b0 [xfs] xfs_bmapi_reserve_delalloc+0x483/0x530 [xfs] xfs_file_iomap_begin+0xac8/0xd40 [xfs] iomap_apply+0xb8/0x1b0 iomap_file_buffered_write+0xac/0xe0 xfs_file_buffered_aio_write+0x198/0x420 [xfs] xfs_file_write_iter+0x23f/0x2a0 [xfs] __vfs_write+0x23e/0x340 vfs_write+0xe9/0x240 SyS_write+0xa1/0x120 do_syscall_64+0xda/0x260 Signed-off-by: Shu Wang <shuwang@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2017-11-16xfs: fix type usageDarrick J. Wong1-1/+1
Be consistent about using uint32_t/uint8_t instead of u32/u8. This is more so that we don't have to maintain /those/ types in xfsprogs. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Eric Sandeen <sandeen@redhat.com>
2017-11-09xfs: handle zero entries case in xfs_iext_rebalance_leafChristoph Hellwig1-7/+17
And also rename fill to nr_entries to match the rest of the code. Reported-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2017-11-09xfs: add comments documenting the rebalance algorithmChristoph Hellwig1-0/+24
Reported-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2017-11-09xfs: trivial indentation fixup for xfs_iext_remove_nodeChristoph Hellwig1-2/+1
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2017-11-09xfs: remove a superflous assignment in xfs_iext_remove_nodeChristoph Hellwig1-1/+0
Reported-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2017-11-09xfs: add some comments to xfs_iext_insert/xfs_iext_insert_nodeChristoph Hellwig1-0/+8
Reported-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2017-11-09xfs: fix number of records handling in xfs_iext_split_leafChristoph Hellwig1-4/+1
Fix to check the correct value, and remove a duplicate handling of the uneven record number split algorith, Reported-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2017-11-06xfs: remove the nr_extents argument to xfs_iext_removeChristoph Hellwig1-22/+8
We only have two places that remove 2 extents at the same time, so unroll the loop there. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2017-11-06xfs: remove the nr_extents argument to xfs_iext_insertChristoph Hellwig1-23/+8
We only have two places that insert 2 extents at the same time, so unroll the loop there. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2017-11-06xfs: use a b+tree for the in-core extent listChristoph Hellwig1-0/+1035
Replace the current linear list and the indirection array for the in-core extent list with a b+tree to avoid the need for larger memory allocations for the indirection array when lots of extents are present. The current extent list implementations leads to heavy pressure on the memory allocator when modifying files with a high extent count, and can lead to high latencies because of that. The replacement is a b+tree with a few quirks. The leaf nodes directly store the extent record in two u64 values. The encoding is a little bit different from the existing in-core extent records so that the start offset and length which are required for lookups can be retreived with simple mask operations. The inner nodes store a 64-bit key containing the start offset in the first half of the node, and the pointers to the next lower level in the second half. In either case we walk the node from the beginninig to the end and do a linear search, as that is more efficient for the low number of cache lines touched during a search (2 for the inner nodes, 4 for the leaf nodes) than a binary search. We store termination markers (zero length for the leaf nodes, an otherwise impossible high bit for the inner nodes) to terminate the key list / records instead of storing a count to use the available cache lines as efficiently as possible. One quirk of the algorithm is that while we normally split a node half and half like usual btree implementations we just spill over entries added at the very end of the list to a new node on its own. This means we get a 100% fill grade for the common cases of bulk insertion when reading an inode into memory, and when only sequentially appending to a file. The downside is a slightly higher chance of splits on the first random insertions. Both insert and removal manually recurse into the lower levels, but the bulk deletion of the whole tree is still implemented as a recursive function call, although one limited by the overall depth and with very little stack usage in every iteration. For the first few extents we dynamically grow the list from a single extent to the next powers of two until we have a first full leaf block and that building the actual tree. The code started out based on the generic lib/btree.c code from Joern Engel based on earlier work from Peter Zijlstra, but has since been rewritten beyond recognition. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>