summaryrefslogtreecommitdiff
path: root/fs/btrfs/scrub.c
AgeCommit message (Collapse)Author
2017-06-19btrfs: remove inode argument from repair_io_failureJosef Bacik
Once we remove the btree_inode we won't have an inode to pass anymore, just pass the fs_info directly and the inum since we use that to print out the repair message. Signed-off-by: Josef Bacik <jbacik@fb.com> Reviewed-by: Chandan Rajendra <chandan@linux.vnet.ibm.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-09block: switch bios to blk_status_tChristoph Hellwig
Replace bi_error with a new bi_status to allow for a clear conversion. Note that device mapper overloaded bi_error with a private value, which we'll have to keep arround at least for now and thus propagate to a proper blk_status_t value. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-18btrfs: scrub: Fix RAID56 recovery race conditionQu Wenruo
When scrubbing a RAID5 which has recoverable data corruption (only one data stripe is corrupted), sometimes scrub will report more csum errors than expected. Sometimes even unrecoverable error will be reported. The problem can be easily reproduced by the following steps: 1) Create a btrfs with RAID5 data profile with 3 devs 2) Mount it with nospace_cache or space_cache=v2 To avoid extra data space usage. 3) Create a 128K file and sync the fs, unmount it Now the 128K file lies at the beginning of the data chunk 4) Locate the physical bytenr of data chunk on dev3 Dev3 is the 1st data stripe. 5) Corrupt the first 64K of the data chunk stripe on dev3 6) Mount the fs and scrub it The correct csum error number should be 16 (assuming using x86_64). Larger csum error number can be reported in a 1/3 chance. And unrecoverable error can also be reported in a 1/10 chance. The root cause of the problem is RAID5/6 recover code has race condition, due to the fact that full scrub is initiated per device. While for other mirror based profiles, each mirror is independent with each other, so race won't cause any big problem. For example: Corrupted | Correct | Correct | | Scrub dev3 (D1) | Scrub dev2 (D2) | Scrub dev1(P) | ------------------------------------------------------------------------ Read out D1 |Read out D2 |Read full stripe | Check csum |Check csum |Check parity | Csum mismatch |Csum match, continue |Parity mismatch | handle_errored_block | |handle_errored_block | Read out full stripe | | Read out full stripe| D1 csum error(err++) | | D1 csum error(err++)| Recover D1 | | Recover D1 | So D1's csum error is accounted twice, just because handle_errored_block() doesn't have enough protection, and race can happen. On even worse case, for example D1's recovery code is re-writing D1/D2/P, and P's recovery code is just reading out full stripe, then we can cause unrecoverable error. This patch will use previously introduced lock_full_stripe() and unlock_full_stripe() to protect the whole scrub_handle_errored_block() function for RAID56 recovery. So no extra csum error nor unrecoverable error. Reported-by: Goffredo Baroncelli <kreijack@libero.it> Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2017-04-18btrfs: scrub: Introduce full stripe lock for RAID56Qu Wenruo
Unlike mirror based profiles, RAID5/6 recovery needs to read out the whole full stripe. And if we don't do proper protection, it can easily cause race condition. Introduce 2 new functions: lock_full_stripe() and unlock_full_stripe() for RAID5/6. Which store a rb_tree of mutexes for full stripes, so scrub callers can use them to lock a full stripe to avoid race. Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com> Reviewed-by: Liu Bo <bo.li.liu@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com> [ minor comment adjustments ] Signed-off-by: David Sterba <dsterba@suse.com>
2017-04-18Btrfs: switch to div64_u64 if with a u64 divisorLiu Bo
This is fixing code pieces where we use div_u64 when passing a u64 divisor. Cc: David Sterba <dsterba@suse.cz> Signed-off-by: Liu Bo <bo.li.liu@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2017-04-18Btrfs: update scrub_parity to use u64 stripe_lenLiu Bo
Commit 3d8da6781760 ("Btrfs: fix divide error upon chunk's stripe_len") changed stripe_len in struct map_lookup to u64, but didn't update stripe_len in struct scrub_parity. This updates the type and switches to div64_u64_rem to match u64 divisor. Cc: David Sterba <dsterba@suse.cz> Signed-off-by: Liu Bo <bo.li.liu@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2017-04-18btrfs: use clear_page where appropriateDavid Sterba
There's a helper to clear whole page, with a arch-specific optimized code. The replaced cases do not seem to be in performace critical code, but we still might get some percent gain. Signed-off-by: David Sterba <dsterba@suse.com>
2017-04-18btrfs: Prevent scrub recheck from racing with dev replaceQu Wenruo
scrub_setup_recheck_block() calls btrfs_map_sblock() and then accesses bbio without protection of bio_counter. This can lead to use-after-free if racing with dev replace cancel. Fix it by increasing bio_counter before calling btrfs_map_sblock() and decreasing the bio_counter when corresponding recover is finished. Cc: Liu Bo <bo.li.liu@oracle.com> Reported-by: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com> Signed-off-by: David Sterba <dsterba@suse.com>
2017-04-18btrfs: Wait for in-flight bios before freeing target device for raid56Qu Wenruo
When raid56 dev-replace is cancelled by running scrub, we will free target device without waiting for in-flight bios, causing the following NULL pointer deference or general protection failure. BUG: unable to handle kernel NULL pointer dereference at 00000000000005e0 IP: generic_make_request_checks+0x4d/0x610 CPU: 1 PID: 11676 Comm: kworker/u4:14 Tainted: G O 4.11.0-rc2 #72 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.10.2-20170228_101828-anatol 04/01/2014 Workqueue: btrfs-endio-raid56 btrfs_endio_raid56_helper [btrfs] task: ffff88002875b4c0 task.stack: ffffc90001334000 RIP: 0010:generic_make_request_checks+0x4d/0x610 Call Trace: ? generic_make_request+0xc7/0x360 generic_make_request+0x24/0x360 ? generic_make_request+0xc7/0x360 submit_bio+0x64/0x120 ? page_in_rbio+0x4d/0x80 [btrfs] ? rbio_orig_end_io+0x80/0x80 [btrfs] finish_rmw+0x3f4/0x540 [btrfs] validate_rbio_for_rmw+0x36/0x40 [btrfs] raid_rmw_end_io+0x7a/0x90 [btrfs] bio_endio+0x56/0x60 end_workqueue_fn+0x3c/0x40 [btrfs] btrfs_scrubparity_helper+0xef/0x620 [btrfs] btrfs_endio_raid56_helper+0xe/0x10 [btrfs] process_one_work+0x2af/0x720 ? process_one_work+0x22b/0x720 worker_thread+0x4b/0x4f0 kthread+0x10f/0x150 ? process_one_work+0x720/0x720 ? kthread_create_on_node+0x40/0x40 ret_from_fork+0x2e/0x40 RIP: generic_make_request_checks+0x4d/0x610 RSP: ffffc90001337bb8 In btrfs_dev_replace_finishing(), we will call btrfs_rm_dev_replace_blocked() to wait bios before destroying the target device when scrub is finished normally. However when dev-replace is aborted, either due to error or cancelled by scrub, we didn't wait for bios, this can lead to use-after-free if there are bios holding the target device. Furthermore, for raid56 scrub, at least 2 places are calling btrfs_map_sblock() without protection of bio_counter, leading to the problem. This patch fixes the problem: 1) Wait for bio_counter before freeing target device when canceling replace 2) When calling btrfs_map_sblock() for raid56, use bio_counter to protect the call. Cc: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com> Reviewed-by: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
2017-04-18btrfs: scrub: Don't append on-disk pages for raid56 scrubQu Wenruo
In the following situation, scrub will calculate wrong parity to overwrite the correct one: RAID5 full stripe: Before | Dev 1 | Dev 2 | Dev 3 | | Data stripe 1 | Data stripe 2 | Parity Stripe | --------------------------------------------------- 0 | 0x0000 (Bad) | 0xcdcd | 0x0000 | --------------------------------------------------- 4K | 0xcdcd | 0xcdcd | 0x0000 | ... | 0xcdcd | 0xcdcd | 0x0000 | --------------------------------------------------- 64K After scrubbing dev3 only: | Dev 1 | Dev 2 | Dev 3 | | Data stripe 1 | Data stripe 2 | Parity Stripe | --------------------------------------------------- 0 | 0xcdcd (Good) | 0xcdcd | 0xcdcd (Bad) | --------------------------------------------------- 4K | 0xcdcd | 0xcdcd | 0x0000 | ... | 0xcdcd | 0xcdcd | 0x0000 | --------------------------------------------------- 64K The reason is that after raid56 read rebuild rbio->stripe_pages are all correctly recovered (0xcd for data stripes). However when we check and repair parity in scrub_parity_check_and_repair(), we will append pages in sparity->spages list to rbio->bio_pages[], which contains old on-disk data. And when we submit parity data to disk, we calculate parity using rbio->bio_pages[] first, if rbio->bio_pages[] not found, then fallback to rbio->stripe_pages[]. The patch fix it by not appending pages from sparity->spages. So finish_parity_scrub() will use rbio->stripe_pages[] which is correct. Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com> Reviewed-by: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
2017-04-18btrfs: drop redundant parameters from btrfs_map_sblockDavid Sterba
All callers pass 0 for mirror_num and 1 for need_raid_map. Signed-off-by: David Sterba <dsterba@suse.com>
2017-04-18Btrfs: set scrub page's io_error if failing to submit ioLiu Bo
Scrub repairs data by the unit called scrub_block, which may contain several pages. Scrub always tries to look up a good copy of a whole block, but if there's no such copy, it tries to do repair page by page. If we don't set page's io_error when checking this bad copy, in the last step, we may skip this page when repairing bad copy from good copy. Cc: David Sterba <dsterba@suse.cz> Signed-off-by: Liu Bo <bo.li.liu@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2017-04-18btrfs: convert scrub_ctx.refs from atomic_t to refcount_tElena Reshetova
refcount_t type and corresponding API should be used instead of atomic_t when the variable is used as a reference counter. This allows to avoid accidental refcounter overflows that might lead to use-after-free situations. Signed-off-by: Elena Reshetova <elena.reshetova@intel.com> Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com> Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: David Windsor <dwindsor@gmail.com> Signed-off-by: David Sterba <dsterba@suse.com>
2017-04-18btrfs: convert scrub_parity.refs from atomic_t to refcount_tElena Reshetova
refcount_t type and corresponding API should be used instead of atomic_t when the variable is used as a reference counter. This allows to avoid accidental refcounter overflows that might lead to use-after-free situations. Signed-off-by: Elena Reshetova <elena.reshetova@intel.com> Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com> Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: David Windsor <dwindsor@gmail.com> Signed-off-by: David Sterba <dsterba@suse.com>
2017-04-18btrfs: convert scrub_block.refs from atomic_t to refcount_tElena Reshetova
refcount_t type and corresponding API should be used instead of atomic_t when the variable is used as a reference counter. This allows to avoid accidental refcounter overflows that might lead to use-after-free situations. Signed-off-by: Elena Reshetova <elena.reshetova@intel.com> Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com> Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: David Windsor <dwindsor@gmail.com> Signed-off-by: David Sterba <dsterba@suse.com>
2017-04-18btrfs: convert scrub_recover.refs from atomic_t to refcount_tElena Reshetova
refcount_t type and corresponding API should be used instead of atomic_t when the variable is used as a reference counter. This allows to avoid accidental refcounter overflows that might lead to use-after-free situations. Signed-off-by: Elena Reshetova <elena.reshetova@intel.com> Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com> Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: David Windsor <dwindsor@gmail.com> Signed-off-by: David Sterba <dsterba@suse.com>
2017-02-28btrfs: Make check_extent_to_block take btrfs_inodeNikolay Borisov
Signed-off-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2017-02-28btrfs: make repair_io_failure take btrfs_inodeNikolay Borisov
Signed-off-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2017-02-28btrfs: Make btrfs_lookup_ordered_range take btrfs_inodeNikolay Borisov
Signed-off-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2017-02-17btrfs: convert btrfs_inc_block_group_ro to accept fs_infoJeff Mahoney
btrfs_inc_block_group_ro is either passed the extent root or the dev root, but it doesn't do anything with the dev tree. Let's convert to passing an fs_info and using the extent root. Signed-off-by: Jeff Mahoney <jeffm@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2017-02-17btrfs: remove unused parameters from scrub_setup_wr_ctxDavid Sterba
Never used. Reviewed-by: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
2016-12-16Merge branch 'for-linus-4.10' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs Pull btrfs updates from Chris Mason: "Jeff Mahoney and Dave Sterba have a really nice set of cleanups in here, and Christoph pitched in corrections/improvements to make btrfs use proper helpers for bio walking instead of doing it by hand. There are some key fixes as well, including some long standing bugs that took forever to track down in btrfs_drop_extents and during balance" * 'for-linus-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (77 commits) btrfs: limit async_work allocation and worker func duration Revert "Btrfs: adjust len of writes if following a preallocated extent" Btrfs: don't WARN() in btrfs_transaction_abort() for IO errors btrfs: opencode chunk locking, remove helpers btrfs: remove root parameter from transaction commit/end routines btrfs: split btrfs_wait_marked_extents into normal and tree log functions btrfs: take an fs_info directly when the root is not used otherwise btrfs: simplify btrfs_wait_cache_io prototype btrfs: convert extent-tree tracepoints to use fs_info btrfs: root->fs_info cleanup, access fs_info->delayed_root directly btrfs: root->fs_info cleanup, add fs_info convenience variables btrfs: root->fs_info cleanup, update_block_group{,flags} btrfs: root->fs_info cleanup, lock/unlock_chunks btrfs: root->fs_info cleanup, btrfs_calc_{trans,trunc}_metadata_size btrfs: pull node/sector/stripe sizes out of root and into fs_info btrfs: root->fs_info cleanup, io_ctl_init btrfs: root->fs_info cleanup, use fs_info->dev_root everywhere btrfs: struct reada_control.root -> reada_control.fs_info btrfs: struct btrfsic_state->root should be an fs_info btrfs: alloc_reserved_file_extent trace point should use extent_root ...
2016-12-06btrfs: remove root parameter from transaction commit/end routinesJeff Mahoney
Now we only use the root parameter to print the root objectid in a tracepoint. We can use the root parameter from the transaction handle for that. It's also used to join the transaction with async commits, so we remove the comment that it's just for checking. Signed-off-by: Jeff Mahoney <jeffm@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2016-12-06btrfs: take an fs_info directly when the root is not used otherwiseJeff Mahoney
There are loads of functions in btrfs that accept a root parameter but only use it to obtain an fs_info pointer. Let's convert those to just accept an fs_info pointer directly. Signed-off-by: Jeff Mahoney <jeffm@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2016-12-06btrfs: root->fs_info cleanup, add fs_info convenience variablesJeff Mahoney
In routines where someptr->fs_info is referenced multiple times, we introduce a convenience variable. This makes the code considerably more readable. Signed-off-by: Jeff Mahoney <jeffm@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2016-12-06btrfs: pull node/sector/stripe sizes out of root and into fs_infoJeff Mahoney
We track the node sizes per-root, but they never vary from the values in the superblock. This patch messes with the 80-column style a bit, but subsequent patches to factor out root->fs_info into a convenience variable fix it up again. Signed-off-by: Jeff Mahoney <jeffm@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2016-12-06btrfs: root->fs_info cleanup, use fs_info->dev_root everywhereJeff Mahoney
Signed-off-by: Jeff Mahoney <jeffm@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2016-11-29btrfs: don't abuse REQ_OP_* flags for btrfs_map_blockChristoph Hellwig
btrfs_map_block supports different types of mappings, which to a large extent resemble block layer operations. But they don't always do, and currently btrfs dangerously overlays it's own flag over the block layer flags. This is just asking for a conflict, so introduce a different map flags enum inside of btrfs instead. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2016-11-01block,fs: use REQ_* flags directlyChristoph Hellwig
Remove the WRITE_* and READ_SYNC wrappers, and just use the flags directly. Where applicable this also drops usage of the bio_set_op_attrs wrapper. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-09-26btrfs: unsplit printed stringsJeff Mahoney
CodingStyle chapter 2: "[...] never break user-visible strings such as printk messages, because that breaks the ability to grep for them." This patch unsplits user-visible strings. Signed-off-by: Jeff Mahoney <jeffm@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2016-08-04Merge branch 'for-linus-4.8' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs Pull more btrfs updates from Chris Mason: "This is part two of my btrfs pull, which is some cleanups and a batch of fixes. Most of the code here is from Jeff Mahoney, making the pointers we pass around internally more consistent and less confusing overall. I noticed a small problem right before I sent this out yesterday, so I fixed it up and re-tested overnight" * 'for-linus-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (40 commits) Btrfs: fix __MAX_CSUM_ITEMS btrfs: btrfs_abort_transaction, drop root parameter btrfs: add btrfs_trans_handle->fs_info pointer btrfs: btrfs_relocate_chunk pass extent_root to btrfs_end_transaction btrfs: convert nodesize macros to static inlines btrfs: introduce BTRFS_MAX_ITEM_SIZE btrfs: cleanup, remove prototype for btrfs_find_root_ref btrfs: copy_to_sk drop unused root parameter btrfs: simpilify btrfs_subvol_inherit_props btrfs: tests, use BTRFS_FS_STATE_DUMMY_FS_INFO instead of dummy root btrfs: tests, require fs_info for root btrfs: tests, move initialization into tests/ btrfs: btrfs_test_opt and friends should take a btrfs_fs_info btrfs: prefix fsid to all trace events btrfs: plumb fs_info into btrfs_work btrfs: remove obsolete part of comment in statfs btrfs: hide test-only member under ifdef btrfs: Ratelimit "no csum found" info message btrfs: Add ratelimit to btrfs printing Btrfs: fix unexpected balance crash due to BUG_ON ...
2016-07-26btrfs: plumb fs_info into btrfs_workJeff Mahoney
In order to provide an fsid for trace events, we'll need a btrfs_fs_info pointer. The most lightweight way to do that for btrfs_work structures is to associate it with the __btrfs_workqueue structure. Each queued btrfs_work structure has a workqueue associated with it, so that's a natural fit. It's a privately defined structures, so we add accessors to retrieve the fs_info pointer. Signed-off-by: Jeff Mahoney <jeffm@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2016-07-26Btrfs: subpage-blocksize: Rate limit scrub error messageChandan Rajendra
btrfs/073 invokes scrub ioctl in a tight loop. In subpage-blocksize scenario this results in a lot of "scrub: size assumption sectorsize != PAGE_SIZE " messages being printed on the console. To reduce the number of such messages this commit uses btrfs_err_rl() instead of btrfs_err(). Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com> Signed-off-by: David Sterba <dsterba@suse.com>
2016-06-07btrfs: use bio op accessorsMike Christie
This should be the easier cases to convert btrfs to bio_set_op_attrs/bio_op. They are mostly just cut and replace type of changes. Signed-off-by: Mike Christie <mchristi@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-06-07block/fs/drivers: remove rw argument from submit_bioMike Christie
This has callers of submit_bio/submit_bio_wait set the bio->bi_rw instead of passing it in. This makes that use the same as generic_make_request and how we set the other bio fields. Signed-off-by: Mike Christie <mchristi@redhat.com> Fixed up fs/ext4/crypto.c Signed-off-by: Jens Axboe <axboe@fb.com>
2016-05-30Btrfs: fix race setting block group back to RW mode during device replaceFilipe Manana
After it finishes processing a device extent, the device replace code sets back the block group to RW mode and then after that it sets the left cursor to match the logical end address of the block group, so that future writes into extents belonging to the block group go both the source (old) and target (new) devices. However from the moment we turn the block group back to RW mode we have a short time window, that lasts until we update the left cursor's value, where extents can be allocated from the block group and written to, in which case they will not be copied/written to the target (new) device. Fix this by updating the left cursor's value before turning the block group back to RW mode. Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: Josef Bacik <jbacik@fb.com>
2016-05-30Btrfs: fix unprotected assignment of the left cursor for device replaceFilipe Manana
We were assigning new values to fields of the device replace object without holding the respective lock after processing each device extent. This is important for the left cursor field which can be accessed by a concurrent task running __btrfs_map_block (which, correctly, takes the device replace lock). So change these fields while holding the device replace lock. Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: Josef Bacik <jbacik@fb.com>
2016-05-30Btrfs: fix race setting block group readonly during device replaceFilipe Manana
When we do a device replace, for each device extent we find from the source device, we set the corresponding block group to readonly mode to prevent writes into it from happening while we are copying the device extent from the source to the target device. However just before we set the block group to readonly mode some concurrent task might have already allocated an extent from it or decided it could perform a nocow write into one of its extents, which can make the device replace process to miss copying an extent since it uses the extent tree's commit root to search for extents and only once it finishes searching for all extents belonging to the block group it does set the left cursor to the logical end address of the block group - this is a problem if the respective ordered extents finish while we are searching for extents using the extent tree's commit root and no transaction commit happens while we are iterating the tree, since it's the delayed references created by the ordered extents (when they complete) that insert the extent items into the extent tree (using the non-commit root of course). Example: CPU 1 CPU 2 btrfs_dev_replace_start() btrfs_scrub_dev() scrub_enumerate_chunks() --> finds device extent belonging to block group X <transaction N starts> starts buffered write against some inode writepages is run against that inode forcing dellaloc to run btrfs_writepages() extent_writepages() extent_write_cache_pages() __extent_writepage() writepage_delalloc() run_delalloc_range() cow_file_range() btrfs_reserve_extent() --> allocates an extent from block group X (which is not yet in RO mode) btrfs_add_ordered_extent() --> creates ordered extent Y flush_epd_write_bio() --> bio against the extent from block group X is submitted btrfs_inc_block_group_ro(bg X) --> sets block group X to readonly scrub_chunk(bg X) scrub_stripe(device extent from srcdev) --> keeps searching for extent items belonging to the block group using the extent tree's commit root --> it never blocks due to fs_info->scrub_pause_req as no one tries to commit transaction N --> copies all extents found from the source device into the target device --> finishes search loop bio completes ordered extent Y completes and creates delayed data reference which will add an extent item to the extent tree when run (typically at transaction commit time) --> so the task doing the scrub/device replace at CPU 1 misses this and does not copy this extent into the new/target device btrfs_dec_block_group_ro(bg X) --> turns block group X back to RW mode dev_replace->cursor_left is set to the logical end offset of block group X So fix this by waiting for all cow and nocow writes after setting a block group to readonly mode. Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: Josef Bacik <jbacik@fb.com>
2016-05-25Merge branch 'cleanups-4.7' into for-chris-4.7-20160525David Sterba
2016-05-25btrfs: fix string and comment grammatical issues and typosNicholas D Steeves
Signed-off-by: Nicholas D Steeves <nsteeves@gmail.com> Signed-off-by: David Sterba <dsterba@suse.com>
2016-05-25btrfs: scrub: Set bbio to NULL before calling btrfs_map_blockZhao Lei
We usually call btrfs_put_bbio() when btrfs_map_block() failed, btrfs_put_bbio() works right whether bbio is a valid value, or NULL. But there is a exception, in some case, btrfs_map_block() will return fail without touching *bbio(keeping its original value), and if bbio was not initialized yet, invalid memory accessing will happened. Above case is in scrub_missing_raid56_pages(), and similar case in scrub_raid56_parity(). Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com> Signed-off-by: David Sterba <dsterba@suse.com>
2016-05-16btrfs: fix memory leak during RAID 5/6 device replacementScott Talbert
A 'struct bio' is allocated in scrub_missing_raid56_pages(), but it was never freed anywhere. Signed-off-by: Scott Talbert <scott.talbert@hgst.com> Signed-off-by: David Sterba <dsterba@suse.com>
2016-05-06btrfs: Fix BUG_ON condition in scrub_setup_recheck_block()Ashish Samant
pagev array in scrub_block{} is of size SCRUB_MAX_PAGES_PER_BLOCK. page_index should be checked with the same to trigger BUG_ON(). Signed-off-by: Ashish Samant <ashish.samant@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2016-05-06Btrfs: fix divide error upon chunk's stripe_lenLiu Bo
The struct 'map_lookup' uses type int for @stripe_len, while btrfs_chunk_stripe_len() can return a u64 value, and it may end up with @stripe_len being undefined value and it can lead to 'divide error' in __btrfs_map_block(). This changes 'map_lookup' to use type u64 for stripe_len, also right now we only use BTRFS_STRIPE_LEN for stripe_len, so this adds a valid checker for BTRFS_STRIPE_LEN. Reported-by: Vegard Nossum <vegard.nossum@oracle.com> Reported-by: Quentin Casasnovas <quentin.casasnovas@oracle.com> Signed-off-by: Liu Bo <bo.li.liu@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com> [ folded division fix to scrub_raid56_parity ] Signed-off-by: David Sterba <dsterba@suse.com>
2016-05-06btrfs: reuse existing variable in scrub_stripe, reduce stack usageDavid Sterba
The key variable occupies 17 bytes, the key_start is used once, we can simply reuse existing 'key' for that purpose. As the key is not a simple type, compiler doest not do it on itself. Signed-off-by: David Sterba <dsterba@suse.com>
2016-04-29btrfs: sink gfp parameter to clear_extent_bitsDavid Sterba
Callers pass GFP_NOFS and GFP_KERNEL. No need to pass the flags around. Signed-off-by: David Sterba <dsterba@suse.com>
2016-04-29btrfs: sink gfp parameter to set_extent_bitsDavid Sterba
All callers pass GFP_NOFS. Signed-off-by: David Sterba <dsterba@suse.com>
2016-04-04mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macrosKirill A. Shutemov
PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time ago with promise that one day it will be possible to implement page cache with bigger chunks than PAGE_SIZE. This promise never materialized. And unlikely will. We have many places where PAGE_CACHE_SIZE assumed to be equal to PAGE_SIZE. And it's constant source of confusion on whether PAGE_CACHE_* or PAGE_* constant should be used in a particular case, especially on the border between fs and mm. Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much breakage to be doable. Let's stop pretending that pages in page cache are special. They are not. The changes are pretty straight-forward: - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN}; - page_cache_get() -> get_page(); - page_cache_release() -> put_page(); This patch contains automated changes generated with coccinelle using script below. For some reason, coccinelle doesn't patch header files. I've called spatch for them manually. The only adjustment after coccinelle is revert of changes to PAGE_CAHCE_ALIGN definition: we are going to drop it later. There are few places in the code where coccinelle didn't reach. I'll fix them manually in a separate patch. Comments and documentation also will be addressed with the separate patch. virtual patch @@ expression E; @@ - E << (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ expression E; @@ - E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ @@ - PAGE_CACHE_SHIFT + PAGE_SHIFT @@ @@ - PAGE_CACHE_SIZE + PAGE_SIZE @@ @@ - PAGE_CACHE_MASK + PAGE_MASK @@ expression E; @@ - PAGE_CACHE_ALIGN(E) + PAGE_ALIGN(E) @@ expression E; @@ - page_cache_get(E) + get_page(E) @@ expression E; @@ - page_cache_release(E) + put_page(E) Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-11btrfs: scrub: silence an uninitialized variable warningDan Carpenter
It's basically harmless if "ref_level" isn't initialized since it's only used for an error message, but it causes a static checker warning. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2016-02-26Merge branch 'foreign/liubo/replace-lockup' into for-chris-4.6David Sterba