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* Merge branch 'xfs-misc-fixes-for-4.3-3' into for-nextDave Chinner2015-08-25
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| * xfs: fix non-debug build warningsDave Chinner2015-08-25
| | | | | | | | | | | | | | | | | | | | | | There seem to be a couple of new set-but-unused build warnings that gcc 4.9.3 is now warning about. These are not regressions, just the compiler being more picky. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
* | xfs: add helper to conditionally remove items from the AILBrian Foster2015-08-19
|/ | | | | | | | | Several areas of code duplicate a pattern where we take the AIL lock, check whether an item is in the AIL and remove it if so. Create a new helper for this pattern and use it where appropriate. Signed-off-by: Brian Foster <bfoster@redhat.com>
* xfs: clarify async write failure ratelimit messageEric Sandeen2015-02-24
| | | | | | | | | | | | | | | | | | Today, when the "failing async writes" get ratelimited, we see: XFS:: 62836 callbacks suppressed Aside from the extra ":" it's not entirely clear which message is being suppressed, especially if other messages or ratelimits are happening at the same time. Clarify this as i.e.: XFS (dm-11): Failing async write on buffer block 0x140090. Retrying async write. XFS: Failing async write: 62836 callbacks suppressed Signed-off-by: Eric Sandeen <sandeen@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Dave Chinner <david@fromorbit.com>
* Merge branch 'xfs-buf-type-fixes' into for-nextDave Chinner2015-01-22
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| * xfs: ensure buffer types are set correctlyDave Chinner2015-01-22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Jan Kara reported that log recovery was finding buffers with invalid types in them. This should not happen, and indicates a bug in the logging of buffers. To catch this, add asserts to the buffer formatting code to ensure that the buffer type is in range when the transaction is committed. We don't set a type on buffers being marked stale - they are not going to get replayed, the format item exists only for recovery to be able to prevent replay of the buffer, so the type does not matter. Hence that needs special casing here. cc: <stable@vger.kernel.org> # 3.10 to current Reported-by: Jan Kara <jack@suse.cz> Tested-by: Jan Kara <jack@suse.cz> Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
* | xfs: remove extra newlines from xfs messagesEric Sandeen2014-12-24
|/ | | | | | | | | | | | | xfs_warn() and friends add a newline by default, but some messages add another one. Particularly for the failing write message below, this can waste a lot of console real estate! Signed-off-by: Eric Sandeen <sandeen@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Dave Chinner <david@fromorbit.com>
* xfs: merge xfs_ag.h into xfs_format.hChristoph Hellwig2014-11-28
| | | | | | | | | | 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>
* Merge branch 'xfs-buf-iosubmit' into for-nextDave Chinner2014-10-02
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| * xfs: introduce xfs_buf_submit[_wait]Dave Chinner2014-10-02
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There is a lot of cookie-cutter code that looks like: if (shutdown) handle buffer error xfs_buf_iorequest(bp) error = xfs_buf_iowait(bp) if (error) handle buffer error spread through XFS. There's significant complexity now in xfs_buf_iorequest() to specifically handle this sort of synchronous IO pattern, but there's all sorts of nasty surprises in different error handling code dependent on who owns the buffer references and the locks. Pull this pattern into a single helper, where we can hide all the synchronous IO warts and hence make the error handling for all the callers much saner. This removes the need for a special extra reference to protect IO completion processing, as we can now hold a single reference across dispatch and waiting, simplifying the sync IO smeantics and error handling. In doing this, also rename xfs_buf_iorequest to xfs_buf_submit and make it explicitly handle on asynchronous IO. This forces all users to be switched specifically to one interface or the other and removes any ambiguity between how the interfaces are to be used. It also means that xfs_buf_iowait() goes away. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Dave Chinner <david@fromorbit.com>
| * xfs: xfs_buf_ioend and xfs_buf_iodone_work duplicate functionalityDave Chinner2014-10-02
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We do some work in xfs_buf_ioend, and some work in xfs_buf_iodone_work, but much of that functionality is the same. This work can all be done in a single function, leaving xfs_buf_iodone just a wrapper to determine if we should execute it by workqueue or directly. hence rename xfs_buf_iodone_work to xfs_buf_ioend(), and add a new xfs_buf_ioend_async() for places that need async processing. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Dave Chinner <david@fromorbit.com>
* | xfs: xfs_buf_write_fail_rl_state can be staticDave Chinner2014-09-23
|/ | | | | | | | | | Fix sparse warning introduced by commit ac8809f9 ("xfs: abort metadata writeback on permanent errors"). Signed-off-by: Fengguang Wu <fengguang.wu@intel.com> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
* xfs: global error sign conversionDave Chinner2014-06-25
| | | | | | | | | | | | | | | | | | | | | | | | | 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>
* Merge branch 'xfs-misc-fixes-3-for-3.16' into for-nextDave Chinner2014-06-10
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| * xfs: kill xfs_buf_geterror()Dave Chinner2014-06-06
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | xfs: remove unused bip arg from xfs_buf_item_log_segment()Eric Sandeen2014-04-14
|/ | | | | | | Signed-off-by: Eric Sandeen <sandeen@redhat.com> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
* xfs: remove XFS_TRANS_DEBUG dead codeJie Liu2014-02-07
| | | | | | | | | | Remove the leftover XFS_TRANS_DEBUG dead code following the previous cleaning up of it in commits ec47eb6b0b450. Signed-off-by: Jie Liu <jeff.liu@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
* Merge branch 'xfs-for-linus-v3.13-rc5' into for-nextBen Myers2013-12-18
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| * xfs: abort metadata writeback on permanent errorsDave Chinner2013-12-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If we are doing aysnc writeback of metadata, we can get write errors but have nobody to report them to. At the moment, we simply attempt to reissue the write from io completion in the hope that it's a transient error. When it's not a transient error, the buffer is stuck forever in this loop, and we cannot break out of it. Eventually, unmount will hang because the AIL cannot be emptied and everything goes downhill from them. To solve this problem, only retry the write IO once before aborting it. We don't throw the buffer away because some transient errors can last minutes (e.g. FC path failover) or even hours (thin provisioned devices that have run out of backing space) before they go away. Hence we really want to keep trying until we can't try any more. Because the buffer was not cleaned, however, it does not get removed from the AIL and hence the next pass across the AIL will start IO on it again. As such, we still get the "retry forever" semantics that we currently have, but we allow other access to the buffer in the mean time. Meanwhile the filesystem can continue to modify the buffer and relog it, so the IO errors won't hang the log or the filesystem. Now when we are pushing the AIL, we can see all these "permanent IO error" buffers and we can issue a warning about failures before we retry the IO. We can also catch these buffers when unmounting an issue a corruption warning, too. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ben Myers <bpm@sgi.com>
* | xfs: format log items write directly into the linear CIL bufferChristoph Hellwig2013-12-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Instead of setting up pointers to memory locations in iop_format which then get copied into the CIL linear buffer after return move the copy into the individual inode items. This avoids the need to always have a memory block in the exact same layout that gets written into the log around, and allow the log items to be much more flexible in their in-memory layouts. The only caveat is that we need to properly align the data for each iovec so that don't have structures misaligned in subsequent iovecs. Note that all log item format routines now need to be careful to modify the copy of the item that was placed into the CIL after calls to xlog_copy_iovec instead of the in-memory copy. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
* | xfs: introduce xlog_copy_iovecChristoph Hellwig2013-12-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Add a helper to abstract out filling the log iovecs in the log item format handlers. This will allow us to change the way we do the log item formatting more easily. The copy in the name is a bit confusing for now as it just assigns a pointer and lets the CIL code perform the copy, but that will change soon. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
* | xfs: refactor xfs_buf_item_format_segmentChristoph Hellwig2013-12-13
|/ | | | | | | | Add two helpers to make the code more readable. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
* xfs: fix static and extern sparse warningsDave Chinner2013-10-30
| | | | | | | | | | | | The kbuild test robot indicated that there were some new sparse warnings in fs/xfs/xfs_dquot_buf.c. Actually, there were a lot more that is wasn't warning about, so fix them all up. Reported-by: kbuild test robot Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Ben Myers <bpm@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
* xfs: decouple log and transaction headersDave Chinner2013-10-23
| | | | | | | | | | | | | | | | | | | | | 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>
* xfs: lock the AIL before removing the buffer itemDave Chinner2013-09-24
| | | | | | | | | | | Regression introduced by commit 46f9d2e ("xfs: aborted buf items can be in the AIL") which fails to lock the AIL before removing the item. Spinlock debugging throws a warning about this. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Mark Tinguely <tinguely@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
* xfs: aborted buf items can be in the AIL.Dave Chinner2013-09-10
| | | | | | | | | | | | | | | | | | | | | | | | | | Saw this on generic/270 after a DQALLOC transaction overrun shutdown: XFS: Assertion failed: !(bip->bli_item.li_flags & XFS_LI_IN_AIL), file: fs/xfs/xfs_buf_item.c, line: 952 ..... xfs_buf_item_relse+0x4f/0xd0 xfs_buf_item_unlock+0x1b4/0x1e0 xfs_trans_free_items+0x7d/0xb0 xfs_trans_cancel+0x13c/0x1b0 xfs_symlink+0x37e/0xa60 .... When a transaction abort occured. If we are aborting a transaction and trigger this code path, then the item may be dirty. If the item is dirty, then it may be in the AIL. Hence if we are aborting, we need to check if the item is in the AIL and remove it before freeing it. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Mark Tinguely <tinguely@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
* xfs: use reference counts to free clean buffer itemsDave Chinner2013-08-15
| | | | | | | | | | | | | | | | When a transaction is cancelled and the buffer log item is clean in the transaction, the buffer log item is unconditionally freed. If the log item is in the AIL, however, this leads to a use after free condition as the item still has other users. In this case, xfs_buf_item_relse() should only be called on clean buffer items if the reference count has dropped to zero. This ensures only the last user frees the item. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Mark Tinguely <tinguely@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
* xfs: return log item size in IOP_SIZEDave Chinner2013-08-13
| | | | | | | | | | | | | | | To begin optimising the CIL commit process, we need to have IOP_SIZE return both the number of vectors and the size of the data pointed to by the vectors. This enables us to calculate the size ofthe memory allocation needed before the formatting step and reduces the number of memory allocations per item by one. While there, kill the IOP_SIZE macro. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Mark Tinguely <tinguely@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
* xfs: Use inode create transactionDave Chinner2013-06-27
| | | | | | | | | | | | | | | | Replace the use of buffer based logging of inode initialisation, uses the new logical form to describe the range to be initialised in recovery. We continue to "log" the inode buffers to push them into the AIL and ensure that the inode create transaction is not removed from the log before the inode buffers are written to disk. Update the transaction identifier and reservations to match the changed implementation. Signed-off-by: Dave Chinner <david@fromorbit.com> Reviewed-by: Mark Tinguely <tinguely@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
* xfs: Introduce an ordered buffer itemDave Chinner2013-06-27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If we have a buffer that we have modified but we do not wish to physically log in a transaction (e.g. we've logged a logical change), we still need to ensure that transactional integrity is maintained. Hence we must not move the tail of the log past the transaction that the buffer is associated with before the buffer is written to disk. This means these special buffers still need to be included in the transaction and added to the AIL just like a normal buffer, but we do not want the modifications to the buffer written into the transaction. IOWs, what we want is an "ordered buffer" that maintains the same transactional life cycle as a physically logged buffer, just without the transcribing of the modifications to the log. Hence we need to flag the buffer as an "ordered buffer" to avoid including it in vector size calculations or formatting during the transaction. Once the transaction is committed, the buffer appears for all intents to be the same as a physically logged buffer as it transitions through the log and AIL. Relogging will also work just fine for such an ordered buffer - the logical transaction will be replayed before the subsequent modifications that relog the buffer, so everything will be reconstructed correctly by recovery. Signed-off-by: Dave Chinner <david@fromorbit.com> Reviewed-by: Mark Tinguely <tinguely@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
* xfs: fix split buffer vector log recovery supportDave Chinner2013-05-30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A long time ago in a galaxy far away.... .. the was a commit made to fix some ilinux specific "fragmented buffer" log recovery problem: http://oss.sgi.com/cgi-bin/gitweb.cgi?p=archive/xfs-import.git;a=commitdiff;h=b29c0bece51da72fb3ff3b61391a391ea54e1603 That problem occurred when a contiguous dirty region of a buffer was split across across two pages of an unmapped buffer. It's been a long time since that has been done in XFS, and the changes to log the entire inode buffers for CRC enabled filesystems has re-introduced that corner case. And, of course, it turns out that the above commit didn't actually fix anything - it just ensured that log recovery is guaranteed to fail when this situation occurs. And now for the gory details. xfstest xfs/085 is failing with this assert: XFS (vdb): bad number of regions (0) in inode log format XFS: Assertion failed: 0, file: fs/xfs/xfs_log_recover.c, line: 1583 Largely undocumented factoid #1: Log recovery depends on all log buffer format items starting with this format: struct foo_log_format { __uint16_t type; __uint16_t size; .... As recoery uses the size field and assumptions about 32 bit alignment in decoding format items. So don't pay much attention to the fact log recovery thinks that it decoding an inode log format item - it just uses them to determine what the size of the item is. But why would it see a log format item with a zero size? Well, luckily enough xfs_logprint uses the same code and gives the same error, so with a bit of gdb magic, it turns out that it isn't a log format that is being decoded. What logprint tells us is this: Oper (130): tid: a0375e1a len: 28 clientid: TRANS flags: none BUF: #regs: 2 start blkno: 144 (0x90) len: 16 bmap size: 2 flags: 0x4000 Oper (131): tid: a0375e1a len: 4096 clientid: TRANS flags: none BUF DATA ---------------------------------------------------------------------------- Oper (132): tid: a0375e1a len: 4096 clientid: TRANS flags: none xfs_logprint: unknown log operation type (4e49) ********************************************************************** * ERROR: data block=2 * ********************************************************************** That we've got a buffer format item (oper 130) that has two regions; the format item itself and one dirty region. The subsequent region after the buffer format item and it's data is them what we are tripping over, and the first bytes of it at an inode magic number. Not a log opheader like there is supposed to be. That means there's a problem with the buffer format item. It's dirty data region is 4096 bytes, and it contains - you guessed it - initialised inodes. But inode buffers are 8k, not 4k, and we log them in their entirety. So something is wrong here. The buffer format item contains: (gdb) p /x *(struct xfs_buf_log_format *)in_f $22 = {blf_type = 0x123c, blf_size = 0x2, blf_flags = 0x4000, blf_len = 0x10, blf_blkno = 0x90, blf_map_size = 0x2, blf_data_map = {0xffffffff, 0xffffffff, .... }} Two regions, and a signle dirty contiguous region of 64 bits. 64 * 128 = 8k, so this should be followed by a single 8k region of data. And the blf_flags tell us that the type of buffer is a XFS_BLFT_DINO_BUF. It contains inodes. And because it doesn't have the XFS_BLF_INODE_BUF flag set, that means it's an inode allocation buffer. So, it should be followed by 8k of inode data. But we know that the next region has a header of: (gdb) p /x *ohead $25 = {oh_tid = 0x1a5e37a0, oh_len = 0x100000, oh_clientid = 0x69, oh_flags = 0x0, oh_res2 = 0x0} and so be32_to_cpu(oh_len) = 0x1000 = 4096 bytes. It's simply not long enough to hold all the logged data. There must be another region. There is - there's a following opheader for another 4k of data that contains the other half of the inode cluster data - the one we assert fail on because it's not a log format header. So why is the second part of the data not being accounted to the correct buffer log format structure? It took a little more work with gdb to work out that the buffer log format structure was both expecting it to be there but hadn't accounted for it. It was at that point I went to the kernel code, as clearly this wasn't a bug in xfs_logprint and the kernel was writing bad stuff to the log. First port of call was the buffer item formatting code, and the discontiguous memory/contiguous dirty region handling code immediately stood out. I've wondered for a long time why the code had this comment in it: vecp->i_addr = xfs_buf_offset(bp, buffer_offset); vecp->i_len = nbits * XFS_BLF_CHUNK; vecp->i_type = XLOG_REG_TYPE_BCHUNK; /* * You would think we need to bump the nvecs here too, but we do not * this number is used by recovery, and it gets confused by the boundary * split here * nvecs++; */ vecp++; And it didn't account for the extra vector pointer. The case being handled here is that a contiguous dirty region lies across a boundary that cannot be memcpy()d across, and so has to be split into two separate operations for xlog_write() to perform. What this code assumes is that what is written to the log is two consecutive blocks of data that are accounted in the buf log format item as the same contiguous dirty region and so will get decoded as such by the log recovery code. The thing is, xlog_write() knows nothing about this, and so just does it's normal thing of adding an opheader for each vector. That means the 8k region gets written to the log as two separate regions of 4k each, but because nvecs has not been incremented, the buf log format item accounts for only one of them. Hence when we come to log recovery, we process the first 4k region and then expect to come across a new item that starts with a log format structure of some kind that tells us whenteh next data is going to be. Instead, we hit raw buffer data and things go bad real quick. So, the commit from 2002 that commented out nvecs++ is just plain wrong. It breaks log recovery completely, and it would seem the only reason this hasn't been since then is that we don't log large contigous regions of multi-page unmapped buffers very often. Never would be a closer estimate, at least until the CRC code came along.... So, lets fix that by restoring the nvecs accounting for the extra region when we hit this case..... .... and there's the problemin log recovery it is apparently working around: XFS: Assertion failed: i == item->ri_total, file: fs/xfs/xfs_log_recover.c, line: 2135 Yup, xlog_recover_do_reg_buffer() doesn't handle contigous dirty regions being broken up into multiple regions by the log formatting code. That's an easy fix, though - if the number of contiguous dirty bits exceeds the length of the region being copied out of the log, only account for the number of dirty bits that region covers, and then loop again and copy more from the next region. It's a 2 line fix. Now xfstests xfs/085 passes, we have one less piece of mystery code, and one more important piece of knowledge about how to structure new log format items.. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Mark Tinguely <tinguely@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
* xfs: recheck buffer pinned status after push trylock failureBrian Foster2013-02-14
| | | | | | | | | | | | | | | | | | | The buffer pinned check and trylock sequence in xfs_buf_item_push() can race with an active transaction on marking the buffer pinned. This can result in the buffer becoming pinned and stale after the initial check and the trylock failure, but before the check in xfs_buf_trylock() that issues a log force. If the log force is issued from this context, a spinlock recursion occurs on xa_lock. Prepare xfs_buf_item_push() to handle the race by detecting a pinned buffer after the trylock failure so xfsaild issues a log force from a safe context. This, along with various previous fixes, renders the log force in xfs_buf_trylock() redundant. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Ben Myers <bpm@sgi.com>
* xfs: fix shutdown hang on invalid inode during createDave Chinner2013-01-26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When the new inode verify in xfs_iread() fails, the create transaction is aborted and a shutdown occurs. The subsequent unmount then hangs in xfs_wait_buftarg() on a buffer that has an elevated hold count. Debug showed that it was an AGI buffer getting stuck: [ 22.576147] XFS (vdb): buffer 0x2/0x1, hold 0x2 stuck [ 22.976213] XFS (vdb): buffer 0x2/0x1, hold 0x2 stuck [ 23.376206] XFS (vdb): buffer 0x2/0x1, hold 0x2 stuck [ 23.776325] XFS (vdb): buffer 0x2/0x1, hold 0x2 stuck The trace of this buffer leading up to the shutdown (trimmed for brevity) looks like: xfs_buf_init: bno 0x2 nblks 0x1 hold 1 caller xfs_buf_get_map xfs_buf_get: bno 0x2 len 0x200 hold 1 caller xfs_buf_read_map xfs_buf_read: bno 0x2 len 0x200 hold 1 caller xfs_trans_read_buf_map xfs_buf_iorequest: bno 0x2 nblks 0x1 hold 1 caller _xfs_buf_read xfs_buf_hold: bno 0x2 nblks 0x1 hold 1 caller xfs_buf_iorequest xfs_buf_rele: bno 0x2 nblks 0x1 hold 2 caller xfs_buf_iorequest xfs_buf_iowait: bno 0x2 nblks 0x1 hold 1 caller _xfs_buf_read xfs_buf_ioerror: bno 0x2 len 0x200 hold 1 caller xfs_buf_bio_end_io xfs_buf_iodone: bno 0x2 nblks 0x1 hold 1 caller _xfs_buf_ioend xfs_buf_iowait_done: bno 0x2 nblks 0x1 hold 1 caller _xfs_buf_read xfs_buf_hold: bno 0x2 nblks 0x1 hold 1 caller xfs_buf_item_init xfs_trans_read_buf: bno 0x2 len 0x200 hold 2 recur 0 refcount 1 xfs_trans_brelse: bno 0x2 len 0x200 hold 2 recur 0 refcount 1 xfs_buf_item_relse: bno 0x2 nblks 0x1 hold 2 caller xfs_trans_brelse xfs_buf_rele: bno 0x2 nblks 0x1 hold 2 caller xfs_buf_item_relse xfs_buf_unlock: bno 0x2 nblks 0x1 hold 1 caller xfs_trans_brelse xfs_buf_rele: bno 0x2 nblks 0x1 hold 1 caller xfs_trans_brelse xfs_buf_trylock: bno 0x2 nblks 0x1 hold 2 caller _xfs_buf_find xfs_buf_find: bno 0x2 len 0x200 hold 2 caller xfs_buf_get_map xfs_buf_get: bno 0x2 len 0x200 hold 2 caller xfs_buf_read_map xfs_buf_read: bno 0x2 len 0x200 hold 2 caller xfs_trans_read_buf_map xfs_buf_hold: bno 0x2 nblks 0x1 hold 2 caller xfs_buf_item_init xfs_trans_read_buf: bno 0x2 len 0x200 hold 3 recur 0 refcount 1 xfs_trans_log_buf: bno 0x2 len 0x200 hold 3 recur 0 refcount 1 xfs_buf_item_unlock: bno 0x2 len 0x200 hold 3 flags DIRTY liflags ABORTED xfs_buf_unlock: bno 0x2 nblks 0x1 hold 3 caller xfs_buf_item_unlock xfs_buf_rele: bno 0x2 nblks 0x1 hold 3 caller xfs_buf_item_unlock And that is the AGI buffer from cold cache read into memory to transaction abort. You can see at transaction abort the bli is dirty and only has a single reference. The item is not pinned, and it's not in the AIL. Hence the only reference to it is this transaction. The problem is that the xfs_buf_item_unlock() call is dropping the last reference to the xfs_buf_log_item attached to the buffer (which holds a reference to the buffer), but it is not freeing the xfs_buf_log_item. Hence nothing will ever release the buffer, and the unmount hangs waiting for this reference to go away. The fix is simple - xfs_buf_item_unlock needs to detect the last reference going away in this case and free the xfs_buf_log_item to release the reference it holds on the buffer. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Ben Myers <bpm@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
* xfs remove the XFS_TRANS_DEBUG routinesMark Tinguely2012-12-17
| | | | | | | | | | | Remove the XFS_TRANS_DEBUG routines. They are no longer appropriate and have not been used in years Signed-off-by: Mark Tinguely <tinguely@sgi.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Ben Myers <bpm@sgi.com>
* xfs: fix the multi-segment log buffer formatMark Tinguely2012-12-17
| | | | | | | | | | | | | Per Dave Chinner suggestion, this patch: 1) Corrects the detection of whether a multi-segment buffer is still tracking data. 2) Clears all the buffer log formats for a multi-segment buffer. Signed-off-by: Mark Tinguely <tinguely@sgi.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Ben Myers <bpm@sgi.com>
* xfs: fix segment in xfs_buf_item_format_segmentMark Tinguely2012-12-17
| | | | | | | | | | | | | Not every segment in a multi-segment buffer is dirty in a transaction and they will not be outputted. The assert in xfs_buf_item_format_segment() that checks for the at least one chunk of data in the segment to be used is not necessary true for multi-segmented buffers. Signed-off-by: Mark Tinguely <tinguely@sgi.com> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Ben Myers <bpm@sgi.com>
* xfs: rename bli_format to avoid confusion with bli_formatsMark Tinguely2012-12-17
| | | | | | | | | | | Rename the bli_format structure to __bli_format to avoid accidently confusing them with the bli_formats pointer. Signed-off-by: Mark Tinguely <tinguely@sgi.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Ben Myers <bpm@sgi.com>
* xfs: fix buffer shudown reference count mismatchDave Chinner2012-11-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When we shut down the filesystem, we have to unpin and free all the buffers currently active in the CIL. To do this we unpin and remove them in one operation as a result of a failed iclogbuf write. For buffers, we do this removal via a simultated IO completion of after marking the buffer stale. At the time we do this, we have two references to the buffer - the active LRU reference and the buf log item. The LRU reference is removed by marking the buffer stale, and the active CIL reference is by the xfs_buf_iodone() callback that is run by xfs_buf_do_callbacks() during ioend processing (via the bp->b_iodone callback). However, ioend processing requires one more reference - that of the IO that it is completing. We don't have this reference, so we free the buffer prematurely and use it after it is freed. For buffers marked with XBF_ASYNC, this leads to assert failures in xfs_buf_rele() on debug kernels because the b_hold count is zero. Fix this by making sure we take the necessary IO reference before starting IO completion processing on the stale buffer, and set the XBF_ASYNC flag to ensure that IO completion processing removes all the active references from the buffer to ensure it is fully torn down. Cc: <stable@vger.kernel.org> Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Mark Tinguely <tinguely@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
* xfs: do not call xfs_bdstrat_cb in xfs_buf_iodone_callbacksChristoph Hellwig2012-07-13
| | | | | | | | | | | | xfs_bdstrat_cb only adds a check for a shutdown filesystem over xfs_buf_iorequest, but xfs_buf_iodone_callbacks just checked for a shut down filesystem a little earlier. In addition the shutdown handling in xfs_bdstrat_cb is not very suitable for this caller. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Ben Myers <bpm@sgi.com>
* xfs: support discontiguous buffers in the xfs_buf_log_itemDave Chinner2012-07-01
| | | | | | | | | | | | | | | | | | | | | | | | | | | discontigous buffer in separate buffer format structures. This means log recovery will recover all the changes on a per segment basis without requiring any knowledge of the fact that it was logged from a compound buffer. To do this, we need to be able to determine what buffer segment any given offset into the compound buffer sits over. This enables us to translate the dirty bitmap in the number of separate buffer format structures required. We also need to be able to determine the number of bitmap elements that a given buffer segment has, as this determines the size of the buffer format structure. Hence we need to be able to determine the both the start offset into the buffer and the length of a given segment to be able to calculate this. With this information, we can preallocate, build and format the correct log vector array for each segment in a compound buffer to appear exactly the same as individually logged buffers in the log. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ben Myers <bpm@sgi.com>
* xfs: struct xfs_buf_log_format isn't variable sized.Dave Chinner2012-07-01
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The struct xfs_buf_log_format wants to think the dirty bitmap is variable sized. In fact, it is variable size on disk simply due to the way we map it from the in-memory structure, but we still just use a fixed size memory allocation for the in-memory structure. Hence it makes no sense to set the function up as a variable sized structure when we already know it's maximum size, and we always allocate it as such. Simplify the structure by making the dirty bitmap a fixed sized array and just using the size of the structure for the allocation size. This will make it much simpler to allocate and manipulate an array of format structures for discontiguous buffer support. The previous struct xfs_buf_log_item size according to /proc/slabinfo was 224 bytes. pahole doesn't give the same size because of the variable size definition. With this modification, pahole reports the same as /proc/slabinfo: /* size: 224, cachelines: 4, members: 6 */ Because the xfs_buf_log_item size is now determined by the maximum supported block size we introduce a dependency on xfs_alloc_btree.h. Avoid this dependency by moving the idefines for the maximum block sizes supported to xfs_types.h with all the other max/min type defines to avoid any new dependencies. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ben Myers <bpm@sgi.com>
* xfs: move xfsagino_t to xfs_types.hDave Chinner2012-05-14
| | | | | | | | | | | 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>
* xfs: use blocks for storing the desired IO sizeDave Chinner2012-05-14
| | | | | | | | | | | | | | | | | | | | | | | | | | | Now that we pass block counts everywhere, and index buffers by block number and length in units of blocks, convert the desired IO size into block counts rather than bytes. Convert the code to use block counts, and those that need byte counts get converted at the time of use. Rename the b_desired_count variable to something closer to it's purpose - b_io_length - as it is only used to specify the length of an IO for a subset of the buffer. The only time this is used is for log IO - both writing iclogs and during log recovery. In all other cases, the b_io_length matches b_length, and hence a lot of code confuses the two. e.g. the buf item code uses the io count exclusively when it should be using the buffer length. Fix these apprpriately as they are found. Also, remove the XFS_BUF_{SET_}COUNT() macros that are just wrappers around the desired IO length. They only serve to make the code shouty loud, don't actually add any real value, and are often used incorrectly. 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>
* xfs: pass shutdown method into xfs_trans_ail_delete_bulkDave Chinner2012-05-14
| | | | | | | | | | | | xfs_trans_ail_delete_bulk() can be called from different contexts so if the item is not in the AIL we need different shutdown for each context. Pass in the shutdown method needed so the correct action can be taken. 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>
* xfs: on-stack delayed write buffer listsChristoph Hellwig2012-05-14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Queue delwri buffers on a local on-stack list instead of a per-buftarg one, and write back the buffers per-process instead of by waking up xfsbufd. This is now easily doable given that we have very few places left that write delwri buffers: - log recovery: Only done at mount time, and already forcing out the buffers synchronously using xfs_flush_buftarg - quotacheck: Same story. - dquot reclaim: Writes out dirty dquots on the LRU under memory pressure. We might want to look into doing more of this via xfsaild, but it's already more optimal than the synchronous inode reclaim that writes each buffer synchronously. - xfsaild: This is the main beneficiary of the change. By keeping a local list of buffers to write we reduce latency of writing out buffers, and more importably we can remove all the delwri list promotions which were hitting the buffer cache hard under sustained metadata loads. The implementation is very straight forward - xfs_buf_delwri_queue now gets a new list_head pointer that it adds the delwri buffers to, and all callers need to eventually submit the list using xfs_buf_delwi_submit or xfs_buf_delwi_submit_nowait. Buffers that already are on a delwri list are skipped in xfs_buf_delwri_queue, assuming they already are on another delwri list. The biggest change to pass down the buffer list was done to the AIL pushing. Now that we operate on buffers the trylock, push and pushbuf log item methods are merged into a single push routine, which tries to lock the item, and if possible add the buffer that needs writeback to the buffer list. This leads to much simpler code than the previous split but requires the individual IOP_PUSH instances to unlock and reacquire the AIL around calls to blocking routines. Given that xfsailds now also handle writing out buffers, the conditions for log forcing and the sleep times needed some small changes. The most important one is that we consider an AIL busy as long we still have buffers to push, and the other one is that we do increment the pushed LSN for buffers that are under flushing at this moment, but still count them towards the stuck items for restart purposes. Without this we could hammer on stuck items without ever forcing the log and not make progress under heavy random delete workloads on fast flash storage devices. [ Dave Chinner: - rebase on previous patches. - improved comments for XBF_DELWRI_Q handling - fix XBF_ASYNC handling in queue submission (test 106 failure) - rename delwri submit function buffer list parameters for clarity - xfs_efd_item_push() should return XFS_ITEM_PINNED ] Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Mark Tinguely <tinguely@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
* xfs: do not add buffers to the delwri queue until pushedChristoph Hellwig2012-05-14
| | | | | | | | | | | | | | | | | Instead of adding buffers to the delwri list as soon as they are logged, even if they can't be written until commited because they are pinned defer adding them to the delwri list until xfsaild pushes them. This makes the code more similar to other log items and prepares for writing buffers directly from xfsaild. The complication here is that we need to fail buffers that were added but not logged yet in xfs_buf_item_unpin, borrowing code from xfs_bioerror. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Mark Tinguely <tinguely@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
* xfs: constify xfs_item_opsChristoph Hellwig2011-11-08
| | | | | | | | | | | The log item ops aren't nessecarily the biggest exploit vector, but marking them const is easy enough. Also remove the unused xfs_item_ops_t typedef while we're at it. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Alex Elder <aelder@sgi.com>
* Merge branch 'master' of ↵Alex Elder2011-10-17
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux Resolved conflicts: fs/xfs/xfs_trans_priv.h: - deleted struct xfs_ail field xa_flags - kept field xa_log_flush in struct xfs_ail fs/xfs/xfs_trans_ail.c: - in xfsaild_push(), in XFS_ITEM_PUSHBUF case, replaced "flush_log = 1" with "ailp->xa_log_flush++" Signed-off-by: Alex Elder <aelder@sgi.com>
| * xfs: force the log if we encounter pinned buffers in .iop_pushbufChristoph Hellwig2011-10-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We need to check for pinned buffers even in .iop_pushbuf given that inode items flush into the same buffers that may be pinned directly due operations on the unlinked inode list operating directly on buffers. To do this add a return value to .iop_pushbuf that tells the AIL push about this and use the existing log force mechanisms to unpin it. Signed-off-by: Christoph Hellwig <hch@lst.de> Reported-by: Stefan Priebe <s.priebe@profihost.ag> Tested-by: Stefan Priebe <s.priebe@profihost.ag> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Alex Elder <aelder@sgi.com>
* | xfs: use xfs_ioerror_alert in xfs_buf_iodone_callbacksChristoph Hellwig2011-10-11
| | | | | | | | | | | | | | | | | | | | | | Use xfs_ioerror_alert instead of opencoding a very similar error message. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Alex Elder <aelder@sgi.com>