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path: root/fs/xfs/xfs_dir2_readdir.c
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2018-01-17xfs: directory scrubber must walk through data block to offsetDarrick J. Wong
In xfs_scrub_dir_rec, we must walk through the directory block entries to arrive at the offset given by the hash structure. If we blindly trust the hash address, we can end up midway into a directory entry and stray outside the block. Found by lastbit fuzzing lents[3].address in xfs/390 with KASAN enabled. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2017-11-06xfs: introduce the xfs_iext_cursor abstractionChristoph Hellwig
Add a new xfs_iext_cursor structure to hide the direct extent map index manipulations. In addition to the existing lookup/get/insert/ remove and update routines new primitives to get the first and last extent cursor, as well as moving up and down by one extent are provided. Also new are convenience to increment/decrement the cursor and retreive the new extent, as well as to peek into the previous/next extent without updating the cursor and last but not least a macro to iterate over all extents in a fork. [darrick: rename for_each_iext to for_each_xfs_iext] 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>
2017-10-26xfs: scrub directory metadataDarrick J. Wong
Scrub the hash tree and all the entries in a directory. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2017-06-20xfs: pass along transaction context when reading directory block buffersDarrick J. Wong
Teach the directory reading functions to pass along a transaction context if one was supplied. The directory scrub code will use transactions to lock buffers and avoid deadlocking with itself in the case of loops. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com>
2017-06-19xfs: remove double-underscore integer typesDarrick J. Wong
This is a purely mechanical patch that removes the private __{u,}int{8,16,32,64}_t typedefs in favor of using the system {u,}int{8,16,32,64}_t typedefs. This is the sed script used to perform the transformation and fix the resulting whitespace and indentation errors: s/typedef\t__uint8_t/typedef __uint8_t\t/g s/typedef\t__uint/typedef __uint/g s/typedef\t__int\([0-9]*\)_t/typedef int\1_t\t/g s/__uint8_t\t/__uint8_t\t\t/g s/__uint/uint/g s/__int\([0-9]*\)_t\t/__int\1_t\t\t/g s/__int/int/g /^typedef.*int[0-9]*_t;$/d Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2017-06-19xfs: refactor dir2 leaf readahead shadow buffer clevernessDarrick J. Wong
Currently, the dir2 leaf block getdents function uses a complex state tracking mechanism to create a shadow copy of the block mappings and then uses the shadow copy to schedule readahead. Since the read and readahead functions are perfectly capable of reading the mappings themselves, we can tear all that out in favor of a simpler function that simply keeps pushing the readahead window further out. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2017-04-25xfs: prevent multi-fsb dir readahead from reading random blocksBrian Foster
Directory block readahead uses a complex iteration mechanism to map between high-level directory blocks and underlying physical extents. This mechanism attempts to traverse the higher-level dir blocks in a manner that handles multi-fsb directory blocks and simultaneously maintains a reference to the corresponding physical blocks. This logic doesn't handle certain (discontiguous) physical extent layouts correctly with multi-fsb directory blocks. For example, consider the case of a 4k FSB filesystem with a 2 FSB (8k) directory block size and a directory with the following extent layout: EXT: FILE-OFFSET BLOCK-RANGE AG AG-OFFSET TOTAL 0: [0..7]: 88..95 0 (88..95) 8 1: [8..15]: 80..87 0 (80..87) 8 2: [16..39]: 168..191 0 (168..191) 24 3: [40..63]: 5242952..5242975 1 (72..95) 24 Directory block 0 spans physical extents 0 and 1, dirblk 1 lies entirely within extent 2 and dirblk 2 spans extents 2 and 3. Because extent 2 is larger than the directory block size, the readahead code erroneously assumes the block is contiguous and issues a readahead based on the physical mapping of the first fsb of the dirblk. This results in read verifier failure and a spurious corruption or crc failure, depending on the filesystem format. Further, the subsequent readahead code responsible for walking through the physical table doesn't correctly advance the physical block reference for dirblk 2. Instead of advancing two physical filesystem blocks, the first iteration of the loop advances 1 block (correctly), but the subsequent iteration advances 2 more physical blocks because the next physical extent (extent 3, above) happens to cover more than dirblk 2. At this point, the higher-level directory block walking is completely off the rails of the actual physical layout of the directory for the respective mapping table. Update the contiguous dirblock logic to consider the current offset in the physical extent to avoid issuing directory readahead to unrelated blocks. Also, update the mapping table advancing code to consider the current offset within the current dirblock to avoid advancing the mapping reference too far beyond the dirblock. Signed-off-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>
2017-04-25xfs: handle array index overrun in xfs_dir2_leaf_readbuf()Eric Sandeen
Carlos had a case where "find" seemed to start spinning forever and never return. This was on a filesystem with non-default multi-fsb (8k) directory blocks, and a fragmented directory with extents like this: 0:[0,133646,2,0] 1:[2,195888,1,0] 2:[3,195890,1,0] 3:[4,195892,1,0] 4:[5,195894,1,0] 5:[6,195896,1,0] 6:[7,195898,1,0] 7:[8,195900,1,0] 8:[9,195902,1,0] 9:[10,195908,1,0] 10:[11,195910,1,0] 11:[12,195912,1,0] 12:[13,195914,1,0] ... i.e. the first extent is a contiguous 2-fsb dir block, but after that it is fragmented into 1 block extents. At the top of the readdir path, we allocate a mapping array which (for this filesystem geometry) can hold 10 extents; see the assignment to map_info->map_size. During readdir, we are therefore able to map extents 0 through 9 above into the array for readahead purposes. If we count by 2, we see that the last mapped index (9) is the first block of a 2-fsb directory block. At the end of xfs_dir2_leaf_readbuf() we have 2 loops to fill more readahead; the outer loop assumes one full dir block is processed each loop iteration, and an inner loop that ensures that this is so by advancing to the next extent until a full directory block is mapped. The problem is that this inner loop may step past the last extent in the mapping array as it tries to reach the end of the directory block. This will read garbage for the extent length, and as a result the loop control variable 'j' may become corrupted and never fail the loop conditional. The number of valid mappings we have in our array is stored in map->map_valid, so stop this inner loop based on that limit. There is an ASSERT at the top of the outer loop for this same condition, but we never made it out of the inner loop, so the ASSERT never fired. Huge appreciation for Carlos for debugging and isolating the problem. Debugged-and-analyzed-by: Carlos Maiolino <cmaiolino@redhat.com> Signed-off-by: Eric Sandeen <sandeen@redhat.com> Tested-by: Carlos Maiolino <cmaiolino@redhat.com> Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com> Reviewed-by: Bill O'Donnell <billodo@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2017-03-15xfs: verify inline directory data forksDarrick J. Wong
When we're reading or writing the data fork of an inline directory, check the contents to make sure we're not overflowing buffers or eating garbage data. xfs/348 corrupts an inline symlink into an inline directory, triggering a buffer overflow bug. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com> --- v2: add more checks consistent with _dir2_sf_check and make the verifier usable from anywhere.
2016-11-30xfs: remove i_iolock and use i_rwsem in the VFS inode insteadChristoph Hellwig
This patch drops the XFS-own i_iolock and uses the VFS i_rwsem which recently replaced i_mutex instead. This means we only have to take one lock instead of two in many fast path operations, and we can also shrink the xfs_inode structure. Thanks to the xfs_ilock family there is very little churn, the only thing of note is that we need to switch to use the lock_two_directory helper for taking the i_rwsem on two inodes in a few places to make sure our lock order matches the one used in the VFS. Signed-off-by: Christoph Hellwig <hch@lst.de> Tested-by: Jens Axboe <axboe@fb.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2016-10-03xfs: return an error when an inline directory is too smallDarrick J. Wong
If the size of an inline directory is so small that it doesn't even cover the required header size, return an error to userspace instead of ASSERTing and returning 0 like everything's ok. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reported-by: Jan Kara <jack@suse.cz> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-05-18xfs: concurrent readdir hangs on data buffer locksDave Chinner
There's a three-process deadlock involving shared/exclusive barriers and inverted lock orders in the directory readdir implementation. It's a pre-existing problem with lock ordering, exposed by the VFS parallelisation code. process 1 process 2 process 3 --------- --------- --------- readdir iolock(shared) get_leaf_dents iterate entries ilock(shared) map, lock and read buffer iunlock(shared) process entries in buffer ..... readdir iolock(shared) get_leaf_dents iterate entries ilock(shared) map, lock buffer <blocks> finish ->iterate_shared file_accessed() ->update_time start transaction ilock(excl) <blocks> ..... finishes processing buffer get next buffer ilock(shared) <blocks> And that's the deadlock. Fix this by dropping the current buffer lock in process 1 before trying to map the next buffer. This means we keep the lock order of ilock -> buffer lock intact and hence will allow process 3 to make progress and drop it's ilock(shared) once it is done. Reported-by: Xiong Zhou <xzhou@redhat.com> Signed-off-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-02-09xfs: mode di_mode to vfs inodeDave Chinner
Move the di_mode value from the xfs_icdinode to the VFS inode, reducing the xfs_icdinode byte another 2 bytes and collapsing another 2 byte hole in the structure. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-10-12xfs: per-filesystem stats counter implementationBill O'Donnell
This patch modifies the stats counting macros and the callers to those macros to properly increment, decrement, and add-to the xfs stats counts. The counts for global and per-fs stats are correctly advanced, and cleared by writing a "1" to the corresponding clear file. global counts: /sys/fs/xfs/stats/stats per-fs counts: /sys/fs/xfs/sda*/stats/stats global clear: /sys/fs/xfs/stats/stats_clear per-fs clear: /sys/fs/xfs/sda*/stats/stats_clear [dchinner: cleaned up macro variables, removed CONFIG_FS_PROC around stats structures and macros. ] Signed-off-by: Bill O'Donnell <billodo@redhat.com> Reviewed-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-08-19xfs: stop holding ILOCK over filldir callbacksDave Chinner
The recent change to the readdir locking made in 40194ec ("xfs: reinstate the ilock in xfs_readdir") for CXFS directory sanity was probably the wrong thing to do. Deep in the readdir code we can take page faults in the filldir callback, and so taking a page fault while holding an inode ilock creates a new set of locking issues that lockdep warns all over the place about. The locking order for regular inodes w.r.t. page faults is io_lock -> pagefault -> mmap_sem -> ilock. The directory readdir code now triggers ilock -> page fault -> mmap_sem. While we cannot deadlock at this point, it inverts all the locking patterns that lockdep normally sees on XFS inodes, and so triggers lockdep. We worked around this with commit 93a8614 ("xfs: fix directory inode iolock lockdep false positive"), but that then just moved the lockdep warning to deeper in the page fault path and triggered on security inode locks. Fixing the shmem issue there just moved the lockdep reports somewhere else, and now we are getting false positives from filesystem freezing annotations getting confused. Further, if we enter memory reclaim in a readdir path, we now get lockdep warning about potential deadlocks because the ilock is held when we enter reclaim. This, again, is different to a regular file in that we never allow memory reclaim to run while holding the ilock for regular files. Hence lockdep now throws ilock->kmalloc->reclaim->ilock warnings. Basically, the problem is that the ilock is being used to protect the directory data and the inode metadata, whereas for a regular file the iolock protects the data and the ilock protects the metadata. From the VFS perspective, the i_mutex serialises all accesses to the directory data, and so not holding the ilock for readdir doesn't matter. The issue is that CXFS doesn't access directory data via the VFS, so it has no "data serialisaton" mechanism. Hence we need to hold the IOLOCK in the correct places to provide this low level directory data access serialisation. The ilock can then be used just when the extent list needs to be read, just like we do for regular files. The directory modification code can take the iolock exclusive when the ilock is also taken, and this then ensures that readdir is correct excluded while modifications are in progress. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-12-04Merge branch 'xfs-misc-fixes-for-3.19-2' into for-nextDave Chinner
Conflicts: fs/xfs/xfs_iops.c
2014-12-04xfs: move ftype conversion functions to libxfsDave Chinner
These functions are needed in userspace for repair and mkfs to do the right thing. Move them to libxfs so they can be easily shared. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-11-28xfs: move most of xfs_sb.h to xfs_format.hChristoph Hellwig
More on-disk format consolidation. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-11-28xfs: merge xfs_ag.h into xfs_format.hChristoph Hellwig
More on-disk format consolidation. A few declarations that weren't on-disk format related move into better suitable spots. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-11-28xfs: merge xfs_dinode.h into xfs_format.hChristoph Hellwig
More consolidatation for the on-disk format defintions. Note that the XFS_IS_REALTIME_INODE moves to xfs_linux.h instead as it is not related to the on disk format, but depends on a CONFIG_ option. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-06-25xfs: global error sign conversionDave Chinner
Convert all the errors the core XFs code to negative error signs like the rest of the kernel and remove all the sign conversion we do in the interface layers. Errors for conversion (and comparison) found via searches like: $ git grep " E" fs/xfs $ git grep "return E" fs/xfs $ git grep " E[A-Z].*;$" fs/xfs Negation points found via searches like: $ git grep "= -[a-z,A-Z]" fs/xfs $ git grep "return -[a-z,A-D,F-Z]" fs/xfs $ git grep " -[a-z].*;" fs/xfs [ with some bits I missed from Brian Foster ] Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-06-22xfs: Nuke XFS_ERROR macroEric Sandeen
XFS_ERROR was designed long ago to trap return values, but it's not runtime configurable, it's not consistently used, and we can do similar error trapping with ftrace scripts and triggers from userspace. Just nuke XFS_ERROR and associated bits. Signed-off-by: Eric Sandeen <sandeen@redhat.com> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-06-10xfs: fix xfs_da_args sparse warning in xfs_readdirDave Chinner
The kbuild test robot reported: >> fs/xfs/xfs_dir2_readdir.c:672:41: sparse: Using plain integer as NULL pointer Fix it. Reported-by: kbuild test robot <fengguang.wu@intel.com> Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-06-06xfs: reduce direct usage of mp->m_dir_geoDave Chinner
There are many places in the directory code were we don't pass the args into and so have to extract the geometry direct from the mount structure. Push the args or the geometry into these leaf functions so that we don't need to grab it from the struct xfs_mount. This, in turn, brings use to the point where directory geometry is no longer a property of the struct xfs_mount; it is not a global property anymore, and hence we can start to consider per-directory configuration of physical geometries. Start by converting the xfs_dir_isblock/leaf code - pass in the xfs_da_args and convert the readdir code to use xfs_da_args like the rest of the directory code to pass information around. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-06-06xfs: convert m_dirblksize to xfs_da_geometryDave Chinner
Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-06-06xfs: convert m_dirblkfsbs to xfs_da_geometryDave Chinner
Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-06-06xfs: convert directory segment limits to xfs_da_geometryDave Chinner
Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-06-06xfs: convert directory db conversion to xfs_da_geometryDave Chinner
Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-06-06xfs: convert directory dablk conversion to xfs_da_geometryDave Chinner
Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-06-06xfs: convert dir byte/off conversion to xfs_da_geometryDave Chinner
Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-05-15Merge branch 'xfs-misc-fixes-1-for-3.16' into for-nextDave Chinner
2014-05-07xfs: fix directory readahead offset off-by-oneDave Chinner
Directory readahead can throw loud scary but harmless warnings when multiblock directories are in use a specific pattern of discontiguous blocks are found in the directory. That is, if a hole follows a discontiguous block, it will throw a warning like: XFS (dm-1): xfs_da_do_buf: bno 637 dir: inode 34363923462 XFS (dm-1): [00] br_startoff 637 br_startblock 1917954575 br_blockcount 1 br_state 0 XFS (dm-1): [01] br_startoff 638 br_startblock -2 br_blockcount 1 br_state 0 And dump a stack trace. This is because the readahead offset increment loop does a double increment of the block index - it does an increment for the loop iteration as well as increase the loop counter by the number of blocks in the extent. As a result, the readahead offset does not get incremented correctly for discontiguous blocks and hence can ask for readahead of a directory block from an offset part way through a directory block. If that directory block is followed by a hole, it will trigger a mapping warning like the above. The bad readahead will be ignored, though, because the main directory block read loop uses the correct mapping offsets rather than the readahead offset and so will ignore the bad readahead altogether. Fix the warning by ensuring that the readahead offset is correctly incremented. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-04-14xfs: remove unused mp arg from xfs_dir2 dataptr/byte functionsEric Sandeen
Signed-off-by: Eric Sandeen <sandeen@redhat.com> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-04-14xfs: remove unused tp arg from xfs_da_reada_buf & callersEric Sandeen
This one hits a few functions as we unravel the unused arg up through the callers. Signed-off-by: Eric Sandeen <sandeen@redhat.com> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-04-14xfs: remove unused tp arg from xfs_bmap_last_offset() and callersEric Sandeen
remove unused transaction pointer from various callchains leading to xfs_bmap_last_offset(). Signed-off-by: Eric Sandeen <sandeen@redhat.com> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2013-12-18xfs: reinstate the ilock in xfs_readdirBen Myers
Although it was removed in commit 051e7cd44ab8, ilock needs to be taken in xfs_readdir because we might have to read the extent list in from disk. This keeps other threads from reading from or writing to the extent list while it is being read in and is still in a transitional state. This has been associated with "Access to block zero" messages on directories with large numbers of extents resulting from excessive filesytem fragmentation, as well as extent list corruption. Unfortunately no test case at this point. Signed-off-by: Ben Myers <bpm@sgi.com> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2013-10-30xfs: convert directory vector functions to constantsDave Chinner
Many of the vectorised function calls now take no parameters and return a constant value. There is no reason for these to be vectored functions, so convert them to constants Binary sizes: text data bss dec hex filename 794490 96802 1096 892388 d9de4 fs/xfs/xfs.o.orig 792986 96802 1096 890884 d9804 fs/xfs/xfs.o.p1 792350 96802 1096 890248 d9588 fs/xfs/xfs.o.p2 789293 96802 1096 887191 d8997 fs/xfs/xfs.o.p3 789005 96802 1096 886903 d8997 fs/xfs/xfs.o.p4 789061 96802 1096 886959 d88af fs/xfs/xfs.o.p5 789733 96802 1096 887631 d8b4f fs/xfs/xfs.o.p6 791421 96802 1096 889319 d91e7 fs/xfs/xfs.o.p7 791701 96802 1096 889599 d92ff fs/xfs/xfs.o.p8 791205 96802 1096 889103 d91cf fs/xfs/xfs.o.p9 Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Ben Myers <bpm@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
2013-10-30xfs: vectorise directory data operations part 2Dave Chinner
Convert the rest of the directory data block encode/decode operations to vector format. This further reduces the size of the built binary: text data bss dec hex filename 794490 96802 1096 892388 d9de4 fs/xfs/xfs.o.orig 792986 96802 1096 890884 d9804 fs/xfs/xfs.o.p1 792350 96802 1096 890248 d9588 fs/xfs/xfs.o.p2 789293 96802 1096 887191 d8997 fs/xfs/xfs.o.p3 789005 96802 1096 886903 d8997 fs/xfs/xfs.o.p4 Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ben Myers <bpm@sgi.com>
2013-10-30xfs: vectorise directory data operationsDave Chinner
Following from the initial patches to vectorise the shortform directory encode/decode operations, convert half the data block operations to use the vector. The rest will be done in a second patch. This further reduces the size of the built binary: text data bss dec hex filename 794490 96802 1096 892388 d9de4 fs/xfs/xfs.o.orig 792986 96802 1096 890884 d9804 fs/xfs/xfs.o.p1 792350 96802 1096 890248 d9588 fs/xfs/xfs.o.p2 789293 96802 1096 887191 d8997 fs/xfs/xfs.o.p3 Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ben Myers <bpm@sgi.com>
2013-10-30xfs: vectorise remaining shortform dir2 opsDave Chinner
Following from the initial patch to introduce the directory operations vector, convert the rest of the shortform directory operations to use vectored ops rather than superblock feature checks. This further reduces the size of the built binary: text data bss dec hex filename 794490 96802 1096 892388 d9de4 fs/xfs/xfs.o.orig 792986 96802 1096 890884 d9804 fs/xfs/xfs.o.p1 792350 96802 1096 890248 d9588 fs/xfs/xfs.o.p2 Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ben Myers <bpm@sgi.com>
2013-10-30xfs: abstract the differences in dir2/dir3 via an ops vectorDave Chinner
Lots of the dir code now goes through switches to determine what is the correct on-disk format to parse. It generally involves a "xfs_sbversion_hasfoo" check, deferencing the superblock version and feature fields and hence touching several cache lines per operation in the process. Some operations do multiple checks because they nest conditional operations and they don't pass the information in a direct fashion between each other. Hence, add an ops vector to the xfs_inode structure that is configured when the inode is initialised to point to all the correct decode and encoding operations. This will significantly reduce the branchiness and cacheline footprint of the directory object decoding and encoding. This is the first patch in a series of conversion patches. It will introduce the ops structure, the setup of it and add the first operation to the vector. Subsequent patches will convert directory ops one at a time to keep the changes simple and obvious. Just this patch shows the benefit of such an approach on code size. Just converting the two shortform dir operations as this patch does decreases the built binary size by ~1500 bytes: $ size fs/xfs/xfs.o.orig fs/xfs/xfs.o.p1 text data bss dec hex filename 794490 96802 1096 892388 d9de4 fs/xfs/xfs.o.orig 792986 96802 1096 890884 d9804 fs/xfs/xfs.o.p1 $ That's a significant decrease in the instruction cache footprint of the directory code for such a simple change, and indicates that this approach is definitely worth pursuing further. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ben Myers <bpm@sgi.com>
2013-10-23xfs: decouple inode and bmap btree header filesDave Chinner
Currently the xfs_inode.h header has a dependency on the definition of the BMAP btree records as the inode fork includes an array of xfs_bmbt_rec_host_t objects in it's definition. Move all the btree format definitions from xfs_btree.h, xfs_bmap_btree.h, xfs_alloc_btree.h and xfs_ialloc_btree.h to xfs_format.h to continue the process of centralising the on-disk format definitions. With this done, the xfs inode definitions are no longer dependent on btree header files. The enables a massive culling of unnecessary includes, with close to 200 #include directives removed from the XFS kernel code base. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Ben Myers <bpm@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
2013-10-23xfs: decouple log and transaction headersDave Chinner
xfs_trans.h has a dependency on xfs_log.h for a couple of structures. Most code that does transactions doesn't need to know anything about the log, but this dependency means that they have to include xfs_log.h. Decouple the xfs_trans.h and xfs_log.h header files and clean up the includes to be in dependency order. In doing this, remove the direct include of xfs_trans_reserve.h from xfs_trans.h so that we remove the dependency between xfs_trans.h and xfs_mount.h. Hence the xfs_trans.h include can be moved to the indicate the actual dependencies other header files have on it. Note that these are kernel only header files, so this does not translate to any userspace changes at all. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Ben Myers <bpm@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
2013-10-23xfs: unify directory/attribute format definitionsDave Chinner
The on-disk format definitions for the directory and attribute structures are spread across 3 header files right now, only one of which is dedicated to defining on-disk structures and their manipulation (xfs_dir2_format.h). Pull all the format definitions into a single header file - xfs_da_format.h - and switch all the code over to point at that. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Ben Myers <bpm@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
2013-09-30xfs: dirent dtype presence is dependent on directory magic numbersDave Chinner
The determination of whether a directory entry contains a dtype field originally was dependent on the filesystem having CRCs enabled. This meant that the format for dtype beign enabled could be determined by checking the directory block magic number rather than doing a feature bit check. This was useful in that it meant that we didn't need to pass a struct xfs_mount around to functions that were already supplied with a directory block header. Unfortunately, the introduction of dtype fields into the v4 structure via a feature bit meant this "use the directory block magic number" method of discriminating the dirent entry sizes is broken. Hence we need to convert the places that use magic number checks to use feature bit checks so that they work correctly and not by chance. The current code works on v4 filesystems only because the dirent size roundup covers the extra byte needed by the dtype field in the places where this problem occurs. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Ben Myers <bpm@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
2013-08-22xfs: Add read-only support for dirent filetype fieldDave Chinner
Add support for the file type field in directory entries so that readdir can return the type of the inode the dirent points to to userspace without first having to read the inode off disk. The encoding of the type field is a single byte that is added to the end of the directory entry name length. For all intents and purposes, it appends a "hidden" byte to the name field which contains the type information. As the directory entry is already of dynamic size, helpers are already required to access and decode the direct entry structures. Hence the relevent extraction and iteration helpers are updated to understand the hidden byte. Helpers for reading and writing the filetype field from the directory entries are also added. Only the read helpers are used by this patch. It also adds all the code necessary to read the type information out of the dirents on disk. Further we add the superblock feature bit and helpers to indicate that we understand the on-disk format change. This is not a compatible change - existing kernels cannot read the new format successfully - so an incompatible feature flag is added. We don't yet allow filesystems to mount with this flag yet - that will be added once write support is added. Finally, the code to take the type from the VFS, convert it to an XFS on-disk type and put it into the xfs_name structures passed around is added, but the directory code does not use this field yet. That will be in the next patch. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Mark Tinguely <tinguely@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
2013-08-12xfs: reshuffle dir2 definitions around for userspaceDave Chinner
Many of the definitions within xfs_dir2_priv.h are needed in userspace outside libxfs. Definitions within xfs_dir2_priv.h are wholly contained within libxfs, so we need to shuffle some of the definitions around to keep consistency across files shared between user and kernel space. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Mark Tinguely <tinguely@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
2013-08-12xfs: move getdents code into it's own fileDave Chinner
The directory readdir code is not used by userspace, but it is intermingled with files that are shared with userspace. This makes it difficult to compare the differences between the userspac eand kernel files are the userspace files don't have the getdents code in them. Move all the kernel getdents code to a separate file to bring the shared content between userspace and kernel files closer together. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Mark Tinguely <tinguely@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>