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path: root/fs/xfs/xfs_bmap_item.c
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2020-10-07xfs: periodically relog deferred intent itemsDarrick J. Wong
There's a subtle design flaw in the deferred log item code that can lead to pinning the log tail. Taking up the defer ops chain examples from the previous commit, we can get trapped in sequences like this: Caller hands us a transaction t0 with D0-D3 attached. The defer ops chain will look like the following if the transaction rolls succeed: t1: D0(t0), D1(t0), D2(t0), D3(t0) t2: d4(t1), d5(t1), D1(t0), D2(t0), D3(t0) t3: d5(t1), D1(t0), D2(t0), D3(t0) ... t9: d9(t7), D3(t0) t10: D3(t0) t11: d10(t10), d11(t10) t12: d11(t10) In transaction 9, we finish d9 and try to roll to t10 while holding onto an intent item for D3 that we logged in t0. The previous commit changed the order in which we place new defer ops in the defer ops processing chain to reduce the maximum chain length. Now make xfs_defer_finish_noroll capable of relogging the entire chain periodically so that we can always move the log tail forward. Most chains will never get relogged, except for operations that generate very long chains (large extents containing many blocks with different sharing levels) or are on filesystems with small logs and a lot of ongoing metadata updates. Callers are now required to ensure that the transaction reservation is large enough to handle logging done items and new intent items for the maximum possible chain length. Most callers are careful to keep the chain lengths low, so the overhead should be minimal. The decision to relog an intent item is made based on whether the intent was logged in a previous checkpoint, since there's no point in relogging an intent into the same checkpoint. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com>
2020-10-07xfs: fix an incore inode UAF in xfs_bui_recoverDarrick J. Wong
In xfs_bui_item_recover, there exists a use-after-free bug with regards to the inode that is involved in the bmap replay operation. If the mapping operation does not complete, we call xfs_bmap_unmap_extent to create a deferred op to finish the unmapping work, and we retain a pointer to the incore inode. Unfortunately, the very next thing we do is commit the transaction and drop the inode. If reclaim tears down the inode before we try to finish the defer ops, we dereference garbage and blow up. Therefore, create a way to join inodes to the defer ops freezer so that we can maintain the xfs_inode reference until we're done with the inode. Note: This imposes the requirement that there be enough memory to keep every incore inode in memory throughout recovery. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2020-10-07xfs: clean up xfs_bui_item_recover iget/trans_alloc/ilock orderingDarrick J. Wong
In most places in XFS, we have a specific order in which we gather resources: grab the inode, allocate a transaction, then lock the inode. xfs_bui_item_recover doesn't do it in that order, so fix it to be more consistent. This also makes the error bailout code a bit less weird. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Brian Foster <bfoster@redhat.com>
2020-10-07xfs: clean up bmap intent item recovery checkingDarrick J. Wong
The bmap intent item checking code in xfs_bui_item_recover is spread all over the function. We should check the recovered log item at the top before we allocate any resources or do anything else, so do that. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2020-10-07xfs: proper replay of deferred ops queued during log recoveryDarrick J. Wong
When we replay unfinished intent items that have been recovered from the log, it's possible that the replay will cause the creation of more deferred work items. As outlined in commit 509955823cc9c ("xfs: log recovery should replay deferred ops in order"), later work items have an implicit ordering dependency on earlier work items. Therefore, recovery must replay the items (both recovered and created) in the same order that they would have been during normal operation. For log recovery, we enforce this ordering by using an empty transaction to collect deferred ops that get created in the process of recovering a log intent item to prevent them from being committed before the rest of the recovered intent items. After we finish committing all the recovered log items, we allocate a transaction with an enormous block reservation, splice our huge list of created deferred ops into that transaction, and commit it, thereby finishing all those ops. This is /really/ hokey -- it's the one place in XFS where we allow nested transactions; the splicing of the defer ops list is is inelegant and has to be done twice per recovery function; and the broken way we handle inode pointers and block reservations cause subtle use-after-free and allocator problems that will be fixed by this patch and the two patches after it. Therefore, replace the hokey empty transaction with a structure designed to capture each chain of deferred ops that are created as part of recovering a single unfinished log intent. Finally, refactor the loop that replays those chains to do so using one transaction per chain. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2020-09-23xfs: don't release log intent items when recovery failsDarrick J. Wong
Nowadays, log recovery will call ->release on the recovered intent items if recovery fails. Therefore, it's redundant to release them from inside the ->recover functions when they're about to return an error. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2020-09-23xfs: attach inode to dquot in xfs_bui_item_recoverDarrick J. Wong
In the bmap intent item recovery code, we must be careful to attach the inode to its dquots (if quotas are enabled) so that a change in the shape of the bmap btree doesn't cause the quota counters to be incorrect. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2020-09-23xfs: log new intent items created as part of finishing recovered intent itemsDarrick J. Wong
During a code inspection, I found a serious bug in the log intent item recovery code when an intent item cannot complete all the work and decides to requeue itself to get that done. When this happens, the item recovery creates a new incore deferred op representing the remaining work and attaches it to the transaction that it allocated. At the end of _item_recover, it moves the entire chain of deferred ops to the dummy parent_tp that xlog_recover_process_intents passed to it, but fail to log a new intent item for the remaining work before committing the transaction for the single unit of work. xlog_finish_defer_ops logs those new intent items once recovery has finished dealing with the intent items that it recovered, but this isn't sufficient. If the log is forced to disk after a recovered log item decides to requeue itself and the system goes down before we call xlog_finish_defer_ops, the second log recovery will never see the new intent item and therefore has no idea that there was more work to do. It will finish recovery leaving the filesystem in a corrupted state. The same logic applies to /any/ deferred ops added during intent item recovery, not just the one handling the remaining work. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2020-07-28xfs: Remove kmem_zone_zalloc() usageCarlos Maiolino
Use kmem_cache_zalloc() directly. With the exception of xlog_ticket_alloc() which will be dealt on the next patch for readability. Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2020-05-08xfs: hoist setting of XFS_LI_RECOVERED to callerDarrick J. Wong
The only purpose of XFS_LI_RECOVERED is to prevent log recovery from trying to replay recovered intents more than once. Therefore, we can move the bit setting up to the ->iop_recover caller. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2020-05-08xfs: refactor intent item iop_recover callsDarrick J. Wong
Now that we've made the recovered item tests all the same, we can hoist the test and the ail locking code to the ->iop_recover caller and call the recovery function directly. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2020-05-08xfs: refactor intent item RECOVERED flag into the log itemDarrick J. Wong
Rename XFS_{EFI,BUI,RUI,CUI}_RECOVERED to XFS_LI_RECOVERED so that we track recovery status in the log item, then get rid of the now unused flags fields in each of those log item types. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2020-05-08xfs: refactor adding recovered intent items to the logDarrick J. Wong
During recovery, every intent that we recover from the log has to be added to the AIL. Replace the open-coded addition with a helper. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
2020-05-08xfs: refactor releasing finished intents during log recoveryDarrick J. Wong
Replace the open-coded AIL item walking with a proper helper when we're trying to release an intent item that has been finished. We add a new ->iop_match method to decide if an intent item matches a supplied ID. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2020-05-08xfs: refactor recovered BUI log item playbackDarrick J. Wong
Move the code that processes the log items created from the recovered log items into the per-item source code files and use dispatch functions to call them. No functional changes. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2020-05-08xfs: refactor log recovery BUI item dispatch for pass2 commit functionsDarrick J. Wong
Move the bmap update intent and intent-done pass2 commit code into the per-item source code files and use dispatch functions to call them. We do these one at a time because there's a lot of code to move. No functional changes. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2020-05-08xfs: refactor log recovery item sorting into a generic dispatch structureDarrick J. Wong
Create a generic dispatch structure to delegate recovery of different log item types into various code modules. This will enable us to move code specific to a particular log item type out of xfs_log_recover.c and into the log item source. The first operation we virtualize is the log item sorting. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2020-05-07xfs: use delete helper for items expected to be in AILBrian Foster
Various intent log items call xfs_trans_ail_remove() with a log I/O error shutdown type, but this helper historically checks whether an item is in the AIL before calling xfs_trans_ail_delete(). This means the shutdown check is essentially a no-op for users of xfs_trans_ail_remove(). It is possible that some items might not be AIL resident when the AIL remove attempt occurs, but this should be isolated to cases where the filesystem has already shutdown. For example, this includes abort of the transaction committing the intent and I/O error of the iclog buffer committing the intent to the log. Therefore, update these callsites to use xfs_trans_ail_delete() to provide AIL state validation for the common path of items being released and removed when associated done items commit to the physical log. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Allison Collins <allison.henderson@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2020-05-04xfs: use a xfs_btree_cur for the ->finish_cleanup stateChristoph Hellwig
Given how XFS is all based around btrees it doesn't make much sense to offer a totally generic state when we can just use the btree cursor. 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>
2020-05-04xfs: turn dfp_done into a xfs_log_itemChristoph Hellwig
All defer op instance place their own extension of the log item into the dfp_done field. Replace that with a xfs_log_item to improve type safety and make the code easier to follow. Also use the opportunity to improve the ->finish_item calling conventions to place the done log item as the higher level structure before the list_entry used for the individual items. 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>
2020-05-04xfs: turn dfp_intent into a xfs_log_itemChristoph Hellwig
All defer op instance place their own extension of the log item into the dfp_intent field. Replace that with a xfs_log_item to improve type safety and make the code easier to follow. 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>
2020-05-04xfs: merge the ->diff_items defer op into ->create_intentChristoph Hellwig
This avoids a per-item indirect call, and also simplifies the interface a bit. 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>
2020-05-04xfs: merge the ->log_item defer op into ->create_intentChristoph Hellwig
These are aways called together, and my merging them we reduce the amount of indirect calls, improve type safety and in general clean up the code a bit. 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>
2019-11-18xfs: Remove kmem_zone_free() wrapperCarlos Maiolino
We can remove it now, without needing to rework the KM_ flags. Use kmem_cache_free() directly. Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2019-11-10xfs: convert EIO to EFSCORRUPTED when log contents are invalidDarrick J. Wong
Convert EIO to EFSCORRUPTED in the logging code when we can determine that the log contents are invalid. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2019-11-04xfs: always log corruption errorsDarrick J. Wong
Make sure we log something to dmesg whenever we return -EFSCORRUPTED up the call stack. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2019-08-28xfs: remove unnecessary int returns from deferred bmap functionsDarrick J. Wong
Remove the return value from the functions that schedule deferred bmap operations since they never fail and do not return status. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2019-08-26fs: xfs: Remove KM_NOSLEEP and KM_SLEEP.Tetsuo Handa
Since no caller is using KM_NOSLEEP and no callee branches on KM_SLEEP, we can remove KM_NOSLEEP and replace KM_SLEEP with 0. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2019-06-28xfs: remove unused header filesEric Sandeen
There are many, many xfs header files which are included but unneeded (or included twice) in the xfs code, so remove them. nb: xfs_linux.h includes about 9 headers for everyone, so those explicit includes get removed by this. I'm not sure what the preference is, but if we wanted explicit includes everywhere, a followup patch could remove those xfs_*.h includes from xfs_linux.h and move them into the files that need them. Or it could be left as-is. Signed-off-by: Eric Sandeen <sandeen@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2019-06-28xfs: merge xfs_trans_bmap.c into xfs_bmap_item.cChristoph Hellwig
Keep all bmap item related code together. 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>
2019-06-28xfs: merge xfs_bud_init into xfs_trans_get_budChristoph Hellwig
There is no good reason to keep these two functions separate. 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>
2019-06-28xfs: remove a pointless comment duplicated above all xfs_item_ops instancesChristoph Hellwig
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>
2019-06-28xfs: add a flag to release log items on commitChristoph Hellwig
We have various items that are released from ->iop_comitting. Add a flag to just call ->iop_release from the commit path to avoid tons of boilerplate code. 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>
2019-06-28xfs: split iop_unlockChristoph Hellwig
The iop_unlock method is called when comitting or cancelling a transaction. In the latter case, the transaction may or may not be aborted. While there is no known problem with the current code in practice, this implementation is limited in that any log item implementation that might want to differentiate between a commit and a cancellation must rely on the aborted state. The aborted bit is only set when the cancelled transaction is dirty, however. This means that there is no way to distinguish between a commit and a clean transaction cancellation. For example, intent log items currently rely on this distinction. The log item is either transferred to the CIL on commit or released on transaction cancel. There is currently no possibility for a clean intent log item in a transaction, but if that state is ever introduced a cancel of such a transaction will immediately result in memory leaks of the associated log item(s). This is an interface deficiency and landmine. To clean this up, replace the iop_unlock method with an iop_release method that is specific to transaction cancel. The existing iop_committing method occurs at the same time as iop_unlock in the commit path and there is no need for two separate callbacks here. Overload the iop_committing method with the current commit time iop_unlock implementations to eliminate the need for the latter and further simplify the interface. 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>
2019-06-28xfs: don't require log items to implement optional methodsChristoph Hellwig
Just check if they are present first. 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>
2019-06-28xfs: move xfs_ino_geometry to xfs_shared.hDarrick J. Wong
The inode geometry structure isn't related to ondisk format; it's support for the mount structure. Move it to xfs_shared.h. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2018-08-02xfs: pass transaction to xfs_defer_add()Brian Foster
The majority of remaining references to struct xfs_defer_ops in XFS are associated with xfs_defer_add(). At this point, there are no more external xfs_defer_ops users left. All instances of xfs_defer_ops are embedded in the transaction, which means we can safely pass the transaction down to the dfops add interface. Update xfs_defer_add() to receive the transaction as a parameter. Various subsystems implement wrappers to allocate and construct the context specific data structures for the associated deferred operation type. Update these to also carry the transaction down as needed and clean up unused dfops parameters along the way. This removes most of the remaining references to struct xfs_defer_ops throughout the code and facilitates removal of the structure. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> [darrick: fix unused variable warnings with ftrace disabled] Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-08-02xfs: drop dop param from xfs_defer_op_type ->finish_item() callbackBrian Foster
The dfops infrastructure ->finish_item() callback passes the transaction and dfops as separate parameters. Since dfops is always part of a transaction, the latter parameter is no longer necessary. Remove it from the various callbacks. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-08-02xfs: pass transaction to dfops reset/move helpersBrian Foster
All callers pass ->t_dfops of the associated transactions. Refactor the helpers to receive the transactions and facilitate further cleanups between xfs_defer_ops and xfs_trans. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-08-02xfs: use transaction for intent recovery instead of raw dfopsBrian Foster
Log intent recovery is the last user of an external (on-stack) dfops. The pattern exists because the dfops is used to collect additional deferred operations queued during the whole recovery sequence. The dfops is finished with a new transaction after intent recovery completes. We already have a mechanism to create an empty, container-like transaction to support the scrub infrastructure. We can reuse that mechanism here to drop the final user of external dfops. This facilitates folding dfops state (i.e., dop_low) into the transaction, the elimination of now unused external dfops support and also eliminates the only caller of __xfs_defer_cancel(). Replace the on-stack dfops with an empty transaction and pass it around to the various helpers that queue and finish deferred operations during intent recovery. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-07-26xfs: clean up IRELE/iput callsitesDarrick J. Wong
Replace the IRELE macro with a proper function so that we can do proper typechecking and so that we can stop open-coding iput in scrub, which means that we'll be able to ftrace inode lifetimes going through scrub correctly. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com>
2018-07-26xfs: use internal dfops during [b|c]ui recoveryBrian Foster
bmap and refcount intent processing associates a dfops from the caller with a local transaction to collect all deferred items for post-processing. Use the internal dfops in both of these functions and move the deferred items to the parent dfops before the transaction commits. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Bill O'Donnell <billodo@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-07-11xfs: use ->t_dfops for recovery of [b|c]ui log itemsBrian Foster
Log recovery passes down a central dfops structure to recovery handlers for bui and cui log items. Each of these handlers allocates and commits a transaction and defers any remaining operations to be completed by the main recovery sequence. Since dfops outlives the transaction in this context, set and clear ->t_dfops appropriately such that the *_finish_item() paths and below (i.e., xfs_bmapi*()) can expect to find the dfops in the transaction without it being committed with the dfops attached. This is required because transaction commit expects that an associated dfops is finished and in this context the dfops may be populated at commit time. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-06-06xfs: convert to SPDX license tagsDave Chinner
Remove the verbose license text from XFS files and replace them with SPDX tags. This does not change the license of any of the code, merely refers to the common, up-to-date license files in LICENSES/ This change was mostly scripted. fs/xfs/Makefile and fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected and modified by the following command: for f in `git grep -l "GNU General" fs/xfs/` ; do echo $f cat $f | awk -f hdr.awk > $f.new mv -f $f.new $f done And the hdr.awk script that did the modification (including detecting the difference between GPL-2.0 and GPL-2.0+ licenses) is as follows: $ cat hdr.awk BEGIN { hdr = 1.0 tag = "GPL-2.0" str = "" } /^ \* This program is free software/ { hdr = 2.0; next } /any later version./ { tag = "GPL-2.0+" next } /^ \*\// { if (hdr > 0.0) { print "// SPDX-License-Identifier: " tag print str print $0 str="" hdr = 0.0 next } print $0 next } /^ \* / { if (hdr > 1.0) next if (hdr > 0.0) { if (str != "") str = str "\n" str = str $0 next } print $0 next } /^ \*/ { if (hdr > 0.0) next print $0 next } // { if (hdr > 0.0) { if (str != "") str = str "\n" str = str $0 next } print $0 } END { } $ Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-05-10xfs: log item flags are racyDave Chinner
The log item flags contain a field that is protected by the AIL lock - the XFS_LI_IN_AIL flag. We use non-atomic RMW operations to set and clear these flags, but most of the updates and checks are not done with the AIL lock held and so are susceptible to update races. Fix this by changing the log item flags to use atomic bitops rather than be reliant on the AIL lock for update serialisation. Signed-Off-By: Dave Chinner <dchinner@redhat.com> Reviewed-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>
2018-04-02xfs: fix intent use-after-free on abortDave Chinner
When an intent is aborted during it's initial commit through xfs_defer_trans_abort(), there is a use after free. The current report is for a RUI through this path in generic/388: Freed by task 6274: __kasan_slab_free+0x136/0x180 kmem_cache_free+0xe7/0x4b0 xfs_trans_free_items+0x198/0x2e0 __xfs_trans_commit+0x27f/0xcc0 xfs_trans_roll+0x17b/0x2a0 xfs_defer_trans_roll+0x6ad/0xe60 xfs_defer_finish+0x2a6/0x2140 xfs_alloc_file_space+0x53a/0xf90 xfs_file_fallocate+0x5c6/0xac0 vfs_fallocate+0x2f5/0x930 ioctl_preallocate+0x1dc/0x320 do_vfs_ioctl+0xfe4/0x1690 The problem is that the RUI has two active references - one in the current transaction, and another held by the defer_ops structure that is passed to the RUD (intent done) so that both the intent and the intent done structures are freed on commit of the intent done. Hence during abort, we need to release the intent item, because the defer_ops reference is released separately via ->abort_intent callback. Fix all the intent code to do this correctly. Signed-Off-By: Dave Chinner <dchinner@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2017-11-27xfs: log recovery should replay deferred ops in orderDarrick J. Wong
As part of testing log recovery with dm_log_writes, Amir Goldstein discovered an error in the deferred ops recovery that lead to corruption of the filesystem metadata if a reflink+rmap filesystem happened to shut down midway through a CoW remap: "This is what happens [after failed log recovery]: "Phase 1 - find and verify superblock... "Phase 2 - using internal log " - zero log... " - scan filesystem freespace and inode maps... " - found root inode chunk "Phase 3 - for each AG... " - scan (but don't clear) agi unlinked lists... " - process known inodes and perform inode discovery... " - agno = 0 "data fork in regular inode 134 claims CoW block 376 "correcting nextents for inode 134 "bad data fork in inode 134 "would have cleared inode 134" Hou Tao dissected the log contents of exactly such a crash: "According to the implementation of xfs_defer_finish(), these ops should be completed in the following sequence: "Have been done: "(1) CUI: Oper (160) "(2) BUI: Oper (161) "(3) CUD: Oper (194), for CUI Oper (160) "(4) RUI A: Oper (197), free rmap [0x155, 2, -9] "Should be done: "(5) BUD: for BUI Oper (161) "(6) RUI B: add rmap [0x155, 2, 137] "(7) RUD: for RUI A "(8) RUD: for RUI B "Actually be done by xlog_recover_process_intents() "(5) BUD: for BUI Oper (161) "(6) RUI B: add rmap [0x155, 2, 137] "(7) RUD: for RUI B "(8) RUD: for RUI A "So the rmap entry [0x155, 2, -9] for COW should be freed firstly, then a new rmap entry [0x155, 2, 137] will be added. However, as we can see from the log record in post_mount.log (generated after umount) and the trace print, the new rmap entry [0x155, 2, 137] are added firstly, then the rmap entry [0x155, 2, -9] are freed." When reconstructing the internal log state from the log items found on disk, it's required that deferred ops replay in exactly the same order that they would have had the filesystem not gone down. However, replaying unfinished deferred ops can create /more/ deferred ops. These new deferred ops are finished in the wrong order. This causes fs corruption and replay crashes, so let's create a single defer_ops to handle the subsequent ops created during replay, then use one single transaction at the end of log recovery to ensure that everything is replayed in the same order as they're supposed to be. Reported-by: Amir Goldstein <amir73il@gmail.com> Analyzed-by: Hou Tao <houtao1@huawei.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Tested-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2017-09-01xfs: remove the ip argument to xfs_defer_finishChristoph Hellwig
And instead require callers to explicitly join the inode using xfs_defer_ijoin. Also consolidate the defer error handling in a few places using a goto label. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2017-06-19xfs: try to avoid blowing out the transaction reservation when bunmaping a ↵Darrick J. Wong
shared extent In a pathological scenario where we are trying to bunmapi a single extent in which every other block is shared, it's possible that trying to unmap the entire large extent in a single transaction can generate so many EFIs that we overflow the transaction reservation. Therefore, use a heuristic to guess at the number of blocks we can safely unmap from a reflink file's data fork in an single transaction. This should prevent problems such as the log head slamming into the tail and ASSERTs that trigger because we've exceeded the transaction reservation. Note that since bunmapi can fail to unmap the entire range, we must also teach the deferred unmap code to roll into a new transaction whenever we get low on reservation. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> [hch: random edits, all bugs are my fault] Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-05-03xfs: reserve enough blocks to handle btree splits when remappingDarrick J. Wong
In xfs_reflink_end_cow, we erroneously reserve only enough blocks to handle adding 1 extent. This is problematic if we fragment free space, have to do CoW, and then have to perform multiple bmap btree expansions. Furthermore, the BUI recovery routine doesn't reserve /any/ blocks to handle btree splits, so log recovery fails after our first error causes the filesystem to go down. Therefore, refactor the transaction block reservation macros until we have a macro that works for our deferred (re)mapping activities, and fix both problems by using that macro. With 1k blocks we can hit this fairly often in g/187 if the scratch fs is big enough. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de>