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2014-06-06xfs: Fix rounding in xfs_alloc_fix_len()Jan Kara1-10/+8
Rounding in xfs_alloc_fix_len() is wrong. As the comment states, the result should be a number of a form (k*prod+mod) however due to sign mistake the result is different. As a result allocations on raid arrays could be misaligned in some cases. This also seems to fix occasional assertion failure: XFS_WANT_CORRUPTED_GOTO(rlen <= flen, error0) in xfs_alloc_ag_vextent_size(). Also add an assertion that the result of xfs_alloc_fix_len() is of expected form. Signed-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-06-06xfs: kill xfs_buf_geterror()Dave Chinner1-1/+0
Most of the callers are just calling ASSERT(!xfs_buf_geterror()) which means they are checking for bp->b_error == 0. If bp is null in this case, we will assert fail, and hence it's no different in result to oopsing because of a null bp. In some cases, errors have already been checked for or the function returning the buffer can't return a buffer with an error, so it's just a redundant assert. Either way, the assert can either be removed. The other two non-assert callers can just test for a buffer and error properly. 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>
2014-02-27xfs: modify verifiers to differentiate CRC from other errorsEric Sandeen1-20/+17
Modify all read & write verifiers to differentiate between CRC errors and other inconsistencies. This sets the appropriate error number on bp->b_error, and then calls xfs_verifier_error() if something went wrong. That function will issue the appropriate message to the user. Signed-off-by: Eric Sandeen <sandeen@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-02-27xfs: add helper for updating checksums on xfs_bufsEric Sandeen1-2/+2
Many/most callers of xfs_update_cksum() pass bp->b_addr and BBTOB(bp->b_length) as the first 2 args. Add a helper which can just accept the bp and the crc offset, and work it out on its own, for brevity. Signed-off-by: Eric Sandeen <sandeen@redhat.com> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-02-27xfs: add helper for verifying checksums on xfs_bufsEric Sandeen1-4/+2
Many/most callers of xfs_verify_cksum() pass bp->b_addr and BBTOB(bp->b_length) as the first 2 args. Add a helper which can just accept the bp and the crc offset, and work it out on its own, for brevity. Signed-off-by: Eric Sandeen <sandeen@redhat.com> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-02-27xfs: Use defines for CRC offsets in all casesEric Sandeen1-6/+4
Some calls to crc functions used useful #defines, others used awkward offsetof() constructs. Switch them all to #define to make things a bit cleaner. Signed-off-by: Eric Sandeen <sandeen@redhat.com> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2013-11-06xfs: add tracepoints to AGF/AGI read operationsDave Chinner1-1/+4
To help track down AGI/AGF lock ordering issues, I added these tracepoints to tell us when an AGI or AGF is read and locked. With these we can now determine if the lock ordering goes wrong from tracing captures. 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 Chinner1-4/+1
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 Chinner1-2/+4
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: create a shared header file for format-related informationDave Chinner1-1/+2
All of the buffer operations structures are needed to be exported for xfs_db, so move them all to a common location rather than spreading them all over the place. They are verifying the on-disk format, so while xfs_format.h might be a good place, it is not part of the on disk format. Hence we need to create a new header file that we centralise these related definitions. Start by moving the bffer operations structures, and then also move all the other definitions that have crept into xfs_log_format.h and xfs_format.h as there was no other shared header file to put them in. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ben Myers <bpm@sgi.com>
2013-08-12xfs: kill __KERNEL__ check for debug code in allocation codeDave Chinner1-3/+3
Userspace running debug builds is relatively rare, so there's need to special case the allocation algorithm code coverage debug switch. As it is, userspace defines random numbers to 0, so invert the logic of the switch so it is effectively a no-op in userspace. This kills another couple of __KERNEL__ users. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Mark Tinguely <tinguely@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
2013-05-20xfs: Avoid pathological backwards allocationJan Kara1-6/+18
Writing a large file using direct IO in 16 MB chunks sometimes results in a pathological allocation pattern where 16 MB chunks of large free extent are allocated to a file in a reversed order. So extents of a file look for example as: ext logical physical expected length flags 0 0 13 4550656 1 4550656 188136807 4550668 12562432 2 17113088 200699240 200699238 622592 3 17735680 182046055 201321831 4096 4 17739776 182041959 182050150 4096 5 17743872 182037863 182046054 4096 6 17747968 182033767 182041958 4096 7 17752064 182029671 182037862 4096 ... 6757 45400064 154381644 154389835 4096 6758 45404160 154377548 154385739 4096 6759 45408256 252951571 154381643 73728 eof This happens because XFS_ALLOCTYPE_THIS_BNO allocation fails (the last extent in the file cannot be further extended) so we fall back to XFS_ALLOCTYPE_NEAR_BNO allocation which picks end of a large free extent as the best place to continue the file. Since the chunk at the end of the free extent again cannot be further extended, this behavior repeats until the whole free extent is consumed in a reversed order. For data allocations this backward allocation isn't beneficial so make xfs_alloc_compute_diff() pick start of a free extent instead of its end for them. That avoids the backward allocation pattern. See thread at http://oss.sgi.com/archives/xfs/2013-03/msg00144.html for more details about the reproduction case and why this solution was chosen. Based on idea by Dave Chinner <dchinner@redhat.com>. CC: Dave Chinner <dchinner@redhat.com> Signed-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Mark Tinguely <tinguely@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
2013-04-27xfs: buffer type overruns blf_flags fieldDave Chinner1-2/+2
The buffer type passed to log recvoery in the buffer log item overruns the blf_flags field. I had assumed that flags field was a 32 bit value, and it turns out it is a unisgned short. Therefore having 19 flags doesn't really work. Convert the buffer type field to numeric value, and use the top 5 bits of the flags field for it. We currently have 17 types of buffers, so using 5 bits gives us plenty of room for expansion in future.... Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Ben Myers <bpm@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
2013-04-21xfs: add CRC checks to the AGFLChristoph Hellwig1-41/+78
Add CRC checks, location information and a magic number to the AGFL. Previously the AGFL was just a block containing nothing but the free block pointers. The new AGFL has a real header with the usual boilerplate instead, so that we can verify it's not corrupted and written into the right place. [dchinner@redhat.com] Added LSN field, reworked significantly to fit into new verifier structure and growfs structure, enabled full verifier functionality now there is a header to verify and we can guarantee an initialised AGFL. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Ben Myers <bpm@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
2013-04-21xfs: add CRC checks to the AGFDave Chinner1-24/+56
The AGF already has some self identifying fields (e.g. the sequence number) so we only need to add the uuid to it to identify the filesystem it belongs to. The location is fixed based on the sequence number, so there's no need to add a block number, either. Hence the only additional fields are the CRC and LSN fields. These are unlogged, so place some space between the end of the logged fields and them so that future expansion of the AGF for logged fields can be placed adjacent to the existing logged fields and hence not complicate the field-derived range based logging we currently have. Based originally on a patch from myself, modified further by Christoph Hellwig and then modified again to fit into the verifier structure with additional fields by myself. The multiple signed-off-by tags indicate the age and history of this patch. Signed-off-by: Dave Chinner <dgc@sgi.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Ben Myers <bpm@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
2013-03-07xfs: rename random32() to prandom_u32()Akinobu Mita1-1/+1
Use more preferable function name which implies using a pseudo-random number generator. Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Acked-by: <bpm@sgi.com> Cc: Ben Myers <bpm@sgi.com> Cc: Alex Elder <elder@kernel.org> Cc: xfs@oss.sgi.com Signed-off-by: Ben Myers <bpm@sgi.com>
2013-01-03xfs: don't zero structure members after a memset(0)Eric Sandeen1-2/+0
Commit 408cc4e97a3ccd172d2d676e4b585badf439271b added memset(0, ...) to allocation args structures, so there is no need to explicitly set any of the fields to 0 after that. Signed-off-by: Eric Sandeen <sandeen@redhat.com> Reviewed-by: Mark Tinguely <tinguely@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
2012-11-15xfs: convert buffer verifiers to an ops structure.Dave Chinner1-12/+16
To separate the verifiers from iodone functions and associate read and write verifiers at the same time, introduce a buffer verifier operations structure to the xfs_buf. This avoids the need for assigning the write verifier, clearing the iodone function and re-running ioend processing in the read verifier, and gets rid of the nasty "b_pre_io" name for the write verifier function pointer. If we ever need to, it will also be easier to add further content specific callbacks to a buffer with an ops structure in place. We also avoid needing to export verifier functions, instead we can simply export the ops structures for those that are needed outside the function they are defined in. This patch also fixes a directory block readahead verifier issue it exposed. This patch also adds ops callbacks to the inode/alloc btree blocks initialised by growfs. These will need more work before they will work with CRCs. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Phil White <pwhite@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
2012-11-15xfs: connect up write verifiers to new buffersDave Chinner1-4/+4
Metadata buffers that are read from disk have write verifiers already attached to them, but newly allocated buffers do not. Add appropriate write verifiers to all new metadata buffers. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Ben Myers <bpm@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
2012-11-15xfs: add pre-write metadata buffer verifier callbacksDave Chinner1-3/+32
These verifiers are essentially the same code as the read verifiers, but do not require ioend processing. Hence factor the read verifier functions and add a new write verifier wrapper that is used as the callback. This is done as one large patch for all verifiers rather than one patch per verifier as the change is largely mechanical. This includes hooking up the write verifier via the read verifier function. Hooking up the write verifier for buffers obtained via xfs_trans_get_buf() will be done in a separate patch as that touches code in many different places rather than just the verifier functions. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Mark Tinguely <tinguely@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
2012-11-15xfs: verify AGFL blocks as they are read from diskDave Chinner1-1/+38
Add an AGFL block verify callback function and pass it into the buffer read functions. While this commit adds verification code to the AGFL, it cannot be used reliably until the CRC format change comes along as mkfs does not initialise the full AGFL. Hence it can be full of garbage at the first mount and will fail verification right now. CRC enabled filesystems won't have this problem, so leave the code that has already been written ifdef'd out until the proper time. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Phil White <pwhite@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
2012-11-15xfs: verify AGF blocks as they are read from diskDave Chinner1-26/+42
Add an AGF block verify callback function and pass it into the buffer read functions. This replaces the existing verification that is done after the read completes. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Mark Tinguely <tinguely@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
2012-11-15xfs: make buffer read verication an IO completion functionDave Chinner1-2/+2
Add a verifier function callback capability to the buffer read interfaces. This will be used by the callers to supply a function that verifies the contents of the buffer when it is read from disk. This patch does not provide callback functions, but simply modifies the interfaces to allow them to be called. The reason for adding this to the read interfaces is that it is very difficult to tell fom the outside is a buffer was just read from disk or whether we just pulled it out of cache. Supplying a callbck allows the buffer cache to use it's internal knowledge of the buffer to execute it only when the buffer is read from disk. It is intended that the verifier functions will mark the buffer with an EFSCORRUPTED error when verification fails. This allows the reading context to distinguish a verification error from an IO error, and potentially take further actions on the buffer (e.g. attempt repair) based on the error reported. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Phil White <pwhite@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
2012-10-18xfs: move allocation stack switch up to xfs_bmapi_allocateDave Chinner1-41/+1
Switching stacks are xfs_alloc_vextent can cause deadlocks when we run out of worker threads on the allocation workqueue. This can occur because xfs_bmap_btalloc can make multiple calls to xfs_alloc_vextent() and even if xfs_alloc_vextent() fails it can return with the AGF locked in the current allocation transaction. If we then need to make another allocation, and all the allocation worker contexts are exhausted because the are blocked waiting for the AGF lock, holder of the AGF cannot get it's xfs-alloc_vextent work completed to release the AGF. Hence allocation effectively deadlocks. To avoid this, move the stack switch one layer up to xfs_bmapi_allocate() so that all of the allocation attempts in a single switched stack transaction occur in a single worker context. This avoids the problem of an allocation being blocked waiting for a worker thread whilst holding the AGF. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Mark Tinguely <tinguely@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
2012-10-18xfs: introduce XFS_BMAPI_STACK_SWITCHDave Chinner1-1/+1
Certain allocation paths through xfs_bmapi_write() are in situations where we have limited stack available. These are almost always in the buffered IO writeback path when convertion delayed allocation extents to real extents. The current stack switch occurs for userdata allocations, which means we also do stack switches for preallocation, direct IO and unwritten extent conversion, even those these call chains have never been implicated in a stack overrun. Hence, let's target just the single stack overun offended for stack switches. To do that, introduce a XFS_BMAPI_STACK_SWITCH flag that the caller can pass xfs_bmapi_write() to indicate it should switch stacks if it needs to do allocation. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Mark Tinguely <tinguely@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
2012-10-18xfs: zero allocation_args on the kernel stackMark Tinguely1-0/+1
Zero the kernel stack space that makes up the xfs_alloc_arg structures. Signed-off-by: Mark Tinguely <tinguely@sgi.com> Reviewed-by: Ben Myers <bpm@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
2012-07-13xfs: don't defer metadata allocation to the workqueueDave Chinner1-3/+12
Almost all metadata allocations come from shallow stack usage situations. Avoid the overhead of switching the allocation to a workqueue as we are not in danger of running out of stack when making these allocations. Metadata allocations are already marked through the args that are passed down, so this is trivial to do. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reported-by: Mel Gorman <mgorman@suse.de> Tested-by: Mel Gorman <mgorman@suse.de> Signed-off-by: Ben Myers <bpm@sgi.com>
2012-07-13xfs: really fix the cursor leak in xfs_alloc_ag_vextent_nearDave Chinner1-2/+2
The current cursor is reallocated when retrying the allocation, so the existing cursor needs to be destroyed in both the restart and the failure cases. Signed-off-by: Dave Chinner <dchinner@redhat.com> Tested-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Ben Myers <bpm@sgi.com>
2012-06-21xfs: fix allocbt cursor leak in xfs_alloc_ag_vextent_nearDave Chinner1-0/+1
When we fail to find an matching extent near the requested extent specification during a left-right distance search in xfs_alloc_ag_vextent_near, we fail to free the original cursor that we used to look up the XFS_BTNUM_CNT tree and hence leak it. Reported-by: Chris J Arges <chris.j.arges@canonical.com> Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ben Myers <bpm@sgi.com>
2012-06-20xfs: fix debug_object WARN at xfs_alloc_vextent()Jeff Liu1-1/+1
Fengguang reports: [ 780.529603] XFS (vdd): Ending clean mount [ 781.454590] ODEBUG: object is on stack, but not annotated [ 781.455433] ------------[ cut here ]------------ [ 781.455433] WARNING: at /c/kernel-tests/sound/lib/debugobjects.c:301 __debug_object_init+0x173/0x1f1() [ 781.455433] Hardware name: Bochs [ 781.455433] Modules linked in: [ 781.455433] Pid: 26910, comm: kworker/0:2 Not tainted 3.4.0+ #51 [ 781.455433] Call Trace: [ 781.455433] [<ffffffff8106bc84>] warn_slowpath_common+0x83/0x9b [ 781.455433] [<ffffffff8106bcb6>] warn_slowpath_null+0x1a/0x1c [ 781.455433] [<ffffffff814919a5>] __debug_object_init+0x173/0x1f1 [ 781.455433] [<ffffffff81491c65>] debug_object_init+0x14/0x16 [ 781.455433] [<ffffffff8108842a>] __init_work+0x20/0x22 [ 781.455433] [<ffffffff8134ea56>] xfs_alloc_vextent+0x6c/0xd5 Use INIT_WORK_ONSTACK in xfs_alloc_vextent instead of INIT_WORK. Reported-by: Wu Fengguang <wfg@linux.intel.com> Signed-off-by: Jie Liu <jeff.liu@oracle.com> Signed-off-by: Ben Myers <bpm@sgi.com>
2012-05-14xfs: make xfs_extent_busy_trim not staticBen Myers1-2/+0
Commit e459df5, 'xfs: move busy extent handling to it's own file' moved some code from xfs_alloc.c into xfs_extent_busy.c for convenience in userspace code merges. One of the functions moved is xfs_extent_busy_trim (formerly xfs_alloc_busy_trim) which is defined STATIC. Unfortunately this function is still used in xfs_alloc.c, and this results in an undefined symbol in xfs.ko. Make xfs_extent_busy_trim not static and add its prototype to xfs_extent_busy.h. Signed-off-by: Ben Myers <bpm@sgi.com> Reviewed-by: Mark Tinguely <tinguely@sgi.com>
2012-05-14xfs: clean up busy extent namingDave Chinner1-6/+6
Now that the busy extent tracking has been moved out of the allocation files, clean up the namespace it uses to "xfs_extent_busy" rather than a mix of "xfs_busy" and "xfs_alloc_busy". Signed-off-by: Dave Chinner<dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Mark Tinguely <tinguely@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
2012-05-14xfs: move busy extent handling to it's own fileDave Chinner1-571/+1
To make it easier to handle userspace code merges, move all the busy extent handling out of the allocation code and into it's own file. The userspace code does not need the busy extent code, so this simplifies the merging of the kernel code into the userspace xfsprogs library. Because the busy extent code has been almost completely rewritten over the past couple of years, also update the copyright on this new file to include the authors that made all those changes. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Mark Tinguely <tinguely@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
2012-05-14xfs: move xfsagino_t to xfs_types.hDave Chinner1-1/+0
Untangle the header file includes a bit by moving the definition of xfs_agino_t to xfs_types.h. This removes the dependency that xfs_ag.h has on xfs_inum.h, meaning we don't need to include xfs_inum.h everywhere we include xfs_ag.h. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Mark Tinguely <tinguely@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
2012-03-27xfs: fix fstrim offset calculationsDave Chinner1-1/+1
xfs_ioc_fstrim() doesn't treat the incoming offset and length correctly. It treats them as a filesystem block address, rather than a disk address. This is wrong because the range passed in is a linear representation, while the filesystem block address notation is a sparse representation. Hence we cannot convert the range direct to filesystem block units and then use that for calculating the range to trim. While this sounds dangerous, the problem is limited to calculating what AGs need to be trimmed. The code that calcuates the actual ranges to trim gets the right result (i.e. only ever discards free space), even though it uses the wrong ranges to limit what is trimmed. Hence this is not a bug that endangers user data. Fix this by treating the range as a disk address range and use the appropriate functions to convert the range into the desired formats for calculations. Further, fix the first free extent lookup (the longest) to actually find the largest free extent. Currently this lookup uses a <= lookup, which results in finding the extent to the left of the largest because we can never get an exact match on the largest extent. This is due to the fact that while we know it's size, we don't know it's location and so the exact match fails and we move one record to the left to get the next largest extent. Instead, use a >= search so that the lookup returns the largest extent regardless of the fact we don't get an exact match on it. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ben Myers <bpm@sgi.com>
2012-03-22xfs: introduce an allocation workqueueDave Chinner1-1/+33
We currently have significant issues with the amount of stack that allocation in XFS uses, especially in the writeback path. We can easily consume 4k of stack between mapping the page, manipulating the bmap btree and allocating blocks from the free list. Not to mention btree block readahead and other functionality that issues IO in the allocation path. As a result, we can no longer fit allocation in the writeback path in the stack space provided on x86_64. To alleviate this problem, introduce an allocation workqueue and move all allocations to a seperate context. This can be easily added as an interposing layer into xfs_alloc_vextent(), which takes a single argument structure and does not return until the allocation is complete or has failed. To do this, add a work structure and a completion to the allocation args structure. This allows xfs_alloc_vextent to queue the args onto the workqueue and wait for it to be completed by the worker. This can be done completely transparently to the caller. The worker function needs to ensure that it sets and clears the PF_TRANS flag appropriately as it is being run in an active transaction context. Work can also be queued in a memory reclaim context, so a rescuer is needed for the workqueue. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ben Myers <bpm@sgi.com>
2011-10-11xfs: remove XFS_BUF_SET_VTYPE and XFS_BUF_SET_VTYPE_REFChristoph Hellwig1-2/+2
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Alex Elder <aelder@sgi.com>
2011-07-25xfs: Remove the macro XFS_BUF_ERROR and familyChandra Seetharaman1-4/+3
Remove the definitions and usage of the macros XFS_BUF_ERROR, XFS_BUF_GETERROR and XFS_BUF_ISERROR. Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
2011-07-08xfs: remove variables that serve no purpose in xfs_alloc_ag_vextent_exact()Chandra Seetharaman1-8/+4
Remove two variables that serve no purpose in xfs_alloc_ag_vextent_exact(). Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com> Signed-off-by: Alex Elder <aelder@sgi.com>
2011-07-08xfs: byteswap constants instead of variablesChristoph Hellwig1-1/+1
Micro-optimize various comparisms by always byteswapping the constant instead of the variable, which allows to do the swap at compile instead of runtime. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Alex Elder <aelder@sgi.com> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2011-05-24xfs: do not discard alloc btree blocksChristoph Hellwig1-3/+6
Blocks for the allocation btree are allocated from and released to the AGFL, and thus frequently reused. Even worse we do not have an easy way to avoid using an AGFL block when it is discarded due to the simple FILO list of free blocks, and thus can frequently stall on blocks that are currently undergoing a discard. Add a flag to the busy extent tracking structure to skip the discard for allocation btree blocks. In normal operation these blocks are reused frequently enough that there is no need to discard them anyway, but if they spill over to the allocation btree as part of a balance we "leak" blocks that we would otherwise discard. We could fix this by adding another flag and keeping these block in the rbtree even after they aren't busy any more so that we could discard them when they migrate out of the AGFL. Given that this would cause significant overhead I don't think it's worthwile for now. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
2011-05-24xfs: add online discard supportChristoph Hellwig1-3/+25
Now that we have reliably tracking of deleted extents in a transaction we can easily implement "online" discard support which calls blkdev_issue_discard once a transaction commits. The actual discard is a two stage operation as we first have to mark the busy extent as not available for reuse before we can start the actual discard. Note that we don't bother supporting discard for the non-delaylog mode. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
2011-05-19xfs: obey minleft values during extent allocation correctlyDave Chinner1-1/+0
When allocating an extent that is long enough to consume the remaining free space in an AG, we need to ensure that the allocation leaves enough space in the AG for any subsequent bmap btree blocks that are needed to track the new extent. These have to be allocated in the same AG as we only reserve enough blocks in an allocation transaction for modification of the freespace trees in a single AG. xfs_alloc_fix_minleft() has been considering blocks on the AGFL as free blocks available for extent and bmbt block allocation, which is not correct - blocks on the AGFL are there exclusively for the use of the free space btrees. As a result, when minleft is less than the number of blocks on the AGFL, xfs_alloc_fix_minleft() does not trim the given extent to leave minleft blocks available for bmbt allocation, and hence we can fail allocation during bmbt record insertion. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
2011-04-28xfs: reduce the number of pagb_lock roundtrips in xfs_alloc_clear_busyChristoph Hellwig1-10/+46
Instead of finding the per-ag and then taking and releasing the pagb_lock for every single busy extent completed sort the list of busy extents and only switch betweens AGs where nessecary. This becomes especially important with the online discard support which will hit this lock more often. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
2011-04-28xfs: exact busy extent trackingChristoph Hellwig1-155/+218
Update the extent tree in case we have to reuse a busy extent, so that it always is kept uptodate. This is done by replacing the busy list searches with a new xfs_alloc_busy_reuse helper, which updates the busy extent tree in case of a reuse. This allows us to allow reusing metadata extents unconditionally, and thus avoid log forces especially for allocation btree blocks. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
2011-04-28xfs: do not immediately reuse busy extent rangesChristoph Hellwig1-79/+328
Every time we reallocate a busy extent, we cause a synchronous log force to occur to ensure the freeing transaction is on disk before we continue and use the newly allocated extent. This is extremely sub-optimal as we have to mark every transaction with blocks that get reused as synchronous. Instead of searching the busy extent list after deciding on the extent to allocate, check each candidate extent during the allocation decisions as to whether they are in the busy list. If they are in the busy list, we trim the busy range out of the extent we have found and determine if that trimmed range is still OK for allocation. In many cases, this check can be incorporated into the allocation extent alignment code which already does trimming of the found extent before determining if it is a valid candidate for allocation. Based on earlier patches from Dave Chinner. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
2011-04-28xfs: optimize AGFL refillsChristoph Hellwig1-27/+4
While we need to make sure we do not reuse busy extents, there is no need to force out busy extents when moving them between the AGFL and the freespace btree as we still take care of that when doing the real allocation. To avoid the log force when just moving extents from the different free space tracking structures, move the busy search out of xfs_alloc_get_freelist into the callers that need it, and move the busy list insert from xfs_free_ag_extent which is used both by AGFL refills and real allocation to xfs_free_extent, which is only used by the latter. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
2011-04-08xfs: catch bad block numbers freeing extents.Dave Chinner1-7/+23
A fuzzed filesystem crashed a kernel when freeing an extent with a block number beyond the end of the filesystem. Convert all the debug asserts in xfs_free_extent() to active checks so that we catch bad extents and return that the filesytsem is corrupted rather than crashing. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Alex Elder <aelder@sgi.com>
2011-03-09xfs: factor agf counter updates into a helperChristoph Hellwig1-61/+68
Updating the AGF and transactions counters is duplicated between allocating and freeing extents. Factor the code into a common helper. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Alex Elder <aelder@sgi.com>
2011-03-09xfs: clean up the xfs_alloc_compute_aligned calling conventionChristoph Hellwig1-16/+13
Pass a xfs_alloc_arg structure to xfs_alloc_compute_aligned and derive the alignment and minlen paramters from it. This cleans up the existing callers, and we'll need even more information from the xfs_alloc_arg in subsequent patches. Based on a patch from Dave Chinner. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Alex Elder <aelder@sgi.com>