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2013-05-09Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs Pull btrfs update from Chris Mason: "These are mostly fixes. The biggest exceptions are Josef's skinny extents and Jan Schmidt's code to rebuild our quota indexes if they get out of sync (or you enable quotas on an existing filesystem). The skinny extents are off by default because they are a new variation on the extent allocation tree format. btrfstune -x enables them, and the new format makes the extent allocation tree about 30% smaller. I rebased this a few days ago to rework Dave Sterba's crc checks on the super block, but almost all of these go back to rc6, since I though 3.9 was due any minute. The biggest missing fix is the tracepoint bug that was hit late in 3.9. I ran into problems with that in overnight testing and I'm still tracking it down. I'll definitely have that fixed for rc2." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (101 commits) Btrfs: allow superblock mismatch from older mkfs btrfs: enhance superblock checks btrfs: fix misleading variable name for flags btrfs: use unsigned long type for extent state bits Btrfs: improve the loop of scrub_stripe btrfs: read entire device info under lock btrfs: remove unused gfp mask parameter from release_extent_buffer callchain btrfs: handle errors returned from get_tree_block_key btrfs: make static code static & remove dead code Btrfs: deal with errors in write_dev_supers Btrfs: remove almost all of the BUG()'s from tree-log.c Btrfs: deal with free space cache errors while replaying log Btrfs: automatic rescan after "quota enable" command Btrfs: rescan for qgroups Btrfs: split btrfs_qgroup_account_ref into four functions Btrfs: allocate new chunks if the space is not enough for global rsv Btrfs: separate sequence numbers for delayed ref tracking and tree mod log btrfs: move leak debug code to functions Btrfs: return free space in cow error path Btrfs: set UUID in root_item for created trees ...
2013-05-06btrfs: make static code static & remove dead codeEric Sandeen
Big patch, but all it does is add statics to functions which are in fact static, then remove the associated dead-code fallout. removed functions: btrfs_iref_to_path() __btrfs_lookup_delayed_deletion_item() __btrfs_search_delayed_insertion_item() __btrfs_search_delayed_deletion_item() find_eb_for_page() btrfs_find_block_group() range_straddles_pages() extent_range_uptodate() btrfs_file_extent_length() btrfs_scrub_cancel_devid() btrfs_start_transaction_lflush() btrfs_print_tree() is left because it is used for debugging. btrfs_start_transaction_lflush() and btrfs_reada_detach() are left for symmetry. ulist.c functions are left, another patch will take care of those. Signed-off-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-05-06Btrfs: don't BUG_ON() in btrfs_num_copiesJosef Bacik
A user sent me a btrfs-image that was panicing because of some corruption. This is because we pass in a bogus value to btrfs_num_copies, and it panics. Instead just return 1. We only call btrfs_num_copies to see if there are other copies to try and read for things, so if we just return 1 it will make the callers exit out with an appropriate error value. Thanks, Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-05-06Btrfs: deal with bad mappings in btrfs_map_blockJosef Bacik
Martin Steigerwald reported a BUG_ON() in btrfs_map_block where we didn't find a chunk for a particular block we were trying to map. This happened because the block was bogus. We shouldn't be BUG_ON()'ing in this case, just print a message and return an error. This came from reada_add_block and it appears to deal with an error fine so we should be good there. Thanks, Reported-by: Martin Steigerwald <Martin@lichtvoll.de> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-05-06Btrfs: use a lock to protect incompat/compat flag of the super blockMiao Xie
The following case will make the incompat/compat flag of the super block be recovered. Task1 |Task2 flags = btrfs_super_incompat_flags(); | |flags = btrfs_super_incompat_flags(); flags |= new_flag1; | |flags |= new_flag2; btrfs_set_super_incompat_flags(flags); | |btrfs_set_super_incompat_flags(flags); the new_flag1 is recovered. In order to avoid this problem, we introduce a lock named super_lock into the btrfs_fs_info structure. If we want to update incompat/compat flags of the super block, we must hold it. Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-05-06btrfs: ignore device open failures in __btrfs_open_devicesEric Sandeen
This: # mkfs.btrfs /dev/sdb{1,2} ; wipefs -a /dev/sdb1; mount /dev/sdb2 /mnt/test would lead to a blkdev open/close mismatch when the mount fails, and a permanently busy (opened O_EXCL) sdb2: # wipefs -a /dev/sdb2 wipefs: error: /dev/sdb2: probing initialization failed: Device or resource busy It's because btrfs_open_devices() may open some devices, fail on the last one, and return that failure stored in "ret." The mount then fails, but the caller then does not clean up the open devices. Chris assures me that: "btrfs_open_devices just means: go off and open every bdev you can from this uuid. It should return success if we opened any of them at all." So change the logic to ignore any open failures; just skip processing of that device. Later on it's decided whether we have enough devices to continue. Reported-by: Jan Safranek <jsafrane@redhat.com> Signed-off-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-05-06Btrfs: fix bad extent loggingJosef Bacik
A user sent me a btrfs-image of a file system that was panicing on mount during the log recovery. I had originally thought these problems were from a bug in the free space cache code, but that was just a symptom of the problem. The problem is if your application does something like this [prealloc][prealloc][prealloc] the internal extent maps will merge those all together into one extent map, even though on disk they are 3 separate extents. So if you go to write into one of these ranges the extent map will be right since we use the physical extent when doing the write, but when we log the extents they will use the wrong sizes for the remainder prealloc space. If this doesn't happen to trip up the free space cache (which it won't in a lot of cases) then you will get bogus entries in your extent tree which will screw stuff up later. The data and such will still work, but everything else is broken. This patch fixes this by not allowing extents that are on the modified list to be merged. This has the side effect that we are no longer adding everything to the modified list all the time, which means we now have to call btrfs_drop_extents every time we log an extent into the tree. So this allows me to drop all this speciality code I was using to get around calling btrfs_drop_extents. With this patch the testcase I've created no longer creates a bogus file system after replaying the log. Thanks, Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-05-06Btrfs: Include the device in most error printk()sSimon Kirby
With more than one btrfs volume mounted, it can be very difficult to find out which volume is hitting an error. btrfs_error() will print this, but it is currently rigged as more of a fatal error handler, while many of the printk()s are currently for debugging and yet-unhandled cases. This patch just changes the functions where the device information is already available. Some cases remain where the root or fs_info is not passed to the function emitting the error. This may introduce some confusion with volumes backed by multiple devices emitting errors referring to the primary device in the set instead of the one on which the error occurred. Use btrfs_printk(fs_info, format, ...) rather than writing the device string every time, and introduce macro wrappers ala XFS for brevity. Since the function already cannot be used for continuations, print a newline as part of the btrfs_printk() message rather than at each caller. Signed-off-by: Simon Kirby <sim@hostway.ca> Reviewed-by: David Sterba <dsterba@suse.cz> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-04-02Merge branch 'writeback-workqueue' of ↵Jens Axboe
git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq into for-3.10/core Tejun writes: ----- This is the pull request for the earlier patchset[1] with the same name. It's only three patches (the first one was committed to workqueue tree) but the merge strategy is a bit involved due to the dependencies. * Because the conversion needs features from wq/for-3.10, block/for-3.10/core is based on rc3, and wq/for-3.10 has conflicts with rc3, I pulled mainline (rc5) into wq/for-3.10 to prevent those workqueue conflicts from flaring up in block tree. * Resolving the issue that Jan and Dave raised about debugging requires arch-wide changes. The patchset is being worked on[2] but it'll have to go through -mm after these changes show up in -next, and not included in this pull request. The three commits are located in the following git branch. git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq.git writeback-workqueue Pulling it into block/for-3.10/core produces a conflict in drivers/md/raid5.c between the following two commits. e3620a3ad5 ("MD RAID5: Avoid accessing gendisk or queue structs when not available") 2f6db2a707 ("raid5: use bio_reset()") The conflict is trivial - one removes an "if ()" conditional while the other removes "rbi->bi_next = NULL" right above it. We just need to remove both. The merged branch is available at git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq.git block-test-merge so that you can use it for verification. The test merge commit has proper merge description. While these changes are a bit of pain to route, they make code simpler and even have, while minute, measureable performance gain[3] even on a workload which isn't particularly favorable to showing the benefits of this conversion. ---- Fixed up the conflict. Conflicts: drivers/md/raid5.c Signed-off-by: Jens Axboe <axboe@kernel.dk>
2013-03-23block: Use bio_sectors() more consistentlyKent Overstreet
Bunch of places in the code weren't using it where they could be - this'll reduce the size of the patch that puts bi_sector/bi_size/bi_idx into a struct bvec_iter. Signed-off-by: Kent Overstreet <koverstreet@google.com> CC: Jens Axboe <axboe@kernel.dk> CC: "Ed L. Cashin" <ecashin@coraid.com> CC: Nick Piggin <npiggin@kernel.dk> CC: Jiri Kosina <jkosina@suse.cz> CC: Jim Paris <jim@jtan.com> CC: Geoff Levand <geoff@infradead.org> CC: Alasdair Kergon <agk@redhat.com> CC: dm-devel@redhat.com CC: Neil Brown <neilb@suse.de> CC: Steven Rostedt <rostedt@goodmis.org> Acked-by: Ed Cashin <ecashin@coraid.com>
2013-03-21Btrfs: handle a bogus chunk tree nicelyJosef Bacik
If you restore a btrfs-image file system and try to mount that file system we'll panic. That's because btrfs-image restores and just makes one big chunk to envelope the whole disk, since they are really only meant to be messed with by our btrfs-progs. So fix up btrfs_rmap_block and the callers of it for mount so that we no longer panic but instead just return an error and fail to mount. Thanks, Signed-off-by: Josef Bacik <jbacik@fusionio.com> Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-03-14btrfs: use rcu_barrier() to wait for bdev puts at unmountEric Sandeen
Doing this would reliably fail with -EBUSY for me: # mount /dev/sdb2 /mnt/scratch; umount /mnt/scratch; mkfs.btrfs -f /dev/sdb2 ... unable to open /dev/sdb2: Device or resource busy because mkfs.btrfs tries to open the device O_EXCL, and somebody still has it. Using systemtap to track bdev gets & puts shows a kworker thread doing a blkdev put after mkfs attempts a get; this is left over from the unmount path: btrfs_close_devices __btrfs_close_devices call_rcu(&device->rcu, free_device); free_device INIT_WORK(&device->rcu_work, __free_device); schedule_work(&device->rcu_work); so unmount might complete before __free_device fires & does its blkdev_put. Adding an rcu_barrier() to btrfs_close_devices() causes unmount to wait until all blkdev_put()s are done, and the device is truly free once unmount completes. Cc: stable@vger.kernel.org Signed-off-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com> Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-03-07Btrfs: fix a mismerge in btrfs_balance()Ilya Dryomov
Raid56 merge (merge commit e942f88) had mistakenly removed a call to __cancel_balance(), which resulted in balance not cleaning up after itself after a successful finish. (Cleanup includes switching the state, removing the balance item and releasing mut_ex_op testnset lock.) Bring it back. Reported-by: David Sterba <dsterba@suse.cz> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-03-04Btrfs: do not BUG_ON on aborted situationLiu Bo
Btrfs balance can easily hit BUG_ON in these places, but we want to it bail out gracefully after we force the whole filesystem to readonly. So we use btrfs_std_error hook in place of BUG_ON. Signed-off-by: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-02-28btrfs: remove a printk from scan_one_deviceDavid Sterba
Dave pointed out that he saw messages from btrfs although there was no such filesystem on his computers. The automatic device scan is called on every new blockdevice if the usual distro udev rule set is used. The printk introduced in 6f60cbd3ae442c was a remainder from copying portions of code from btrfs_get_bdev_and_sb which is used under different conditions and the warning makes sense there. Reported-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: David Sterba <dsterba@suse.cz> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-02-26btrfs: cleanup for open-coded alignmentQu Wenruo
Though most of the btrfs codes are using ALIGN macro for page alignment, there are still some codes using open-coded alignment like the following: ------ u64 mask = ((u64)root->stripesize - 1); u64 ret = (val + mask) & ~mask; ------ Or even hidden one: ------ num_bytes = (end - start + blocksize) & ~(blocksize - 1); ------ Sometimes these open-coded alignment is not so easy to understand for newbie like me. This commit changes the open-coded alignment to the ALIGN macro for a better readability. Also there is a previous patch from David Sterba with similar changes, but the patch is for 3.2 kernel and seems not merged. http://www.spinics.net/lists/linux-btrfs/msg12747.html Cc: David Sterba <dave@jikos.cz> Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-02-20Btrfs: fix max chunk size on raid5/6Chris Mason
We try to limit the size of a chunk to 10GB, which keeps the unit of work reasonable during balance and resize operations. The limit checks were taking into account the number of copies of the data we had but what they really should be doing is comparing against the logical size of the chunk we're creating. This moves the code around a little to use the count of data stripes from raid5/6. Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-02-20btrfs: Init io_lock after cloning btrfs device structThomas Gleixner
__btrfs_close_devices() clones btrfs device structs with memcpy(). Some of the fields in the clone are reinitialized, but it's missing to init io_lock. In mainline this goes unnoticed, but on RT it leaves the plist pointing to the original about to be freed lock struct. Initialize io_lock after cloning, so no references to the original struct are left. Reported-and-tested-by: Mike Galbraith <efault@gmx.de> Cc: stable@vger.kernel.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-02-20Merge branch 'raid56-experimental' into for-linus-3.9Chris Mason
Signed-off-by: Chris Mason <chris.mason@fusionio.com> Conflicts: fs/btrfs/ctree.h fs/btrfs/extent-tree.c fs/btrfs/inode.c fs/btrfs/volumes.c
2013-02-20btrfs: define BTRFS_MAGIC as a u64 valueZach Brown
super.magic is an le64 but it's treated as an unterminated string when compared against BTRFS_MAGIC which is defined as a string. Instead define BTRFS_MAGIC as a normal hex value and use endian helpers to compare it to the super's magic. I tested this by mounting an fs made before the change and made sure that it didn't introduce sparse errors. This matches a similar cleanup that is pending in btrfs-progs. David Sterba pointed out that we should fix the kernel side as well :). Signed-off-by: Zach Brown <zab@redhat.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-02-20Btrfs: allow for selecting only completely empty chunksIlya Dryomov
Enhance balance usage filter by making it possible to balance out only completely empty chunks. Today, usage filter properly acts on values from 1 to 99 inclusive, usage=100 selects all chunks, and usage=0 selects no chunks. This commit changes the usage=0 case: the new meaning is to restripe only completely empty chunks and nothing else. Suggested-by: David Sterba <dsterba@suse.cz> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-02-20Btrfs: eliminate a use-after-free in btrfs_balance()Ilya Dryomov
Commit 5af3e8cc introduced a use-after-free at volumes.c:3139: bctl is freed above in __cancel_balance() in all cases except for balance pause. Fix this by moving the offending check a couple statements above, the meaning of the check is preserved. Reported-by: Chris Mason <chris.mason@fusionio.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-02-20btrfs: ensure we don't overrun devices_info[] in __btrfs_alloc_chunkEric Sandeen
WARN_ON isn't enough, we need to stop the loop if for any reason we would overrun the devices_info array. I tried to track down the connection between the length of the alloc_devices list and the rw_devices counter but it wasn't immediately obvious, so be defensive about it. Signed-off-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-02-20Btrfs: remove extent mapping if we fail to add chunkJosef Bacik
I got a double free error when unmounting a file system that failed to add a chunk during its operation. This is because we will kfree the mapping that we created but leave the extent_map in the em_tree for chunks. So to fix this just remove the extent_map when we error out so we don't run into this problem. Thanks, Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-02-20Btrfs: fix chunk allocation error handlingJosef Bacik
If we error out allocating a dev extent we will have already created the block group and such which will cause problems since the allocator may have tried to allocate out of the block group that no longer exists. This will cause BUG_ON()'s in the bio submission path. This also makes a failure to allocate a dev extent a non-abort error, we will just clean up the dev extents we did allocate and exit. Now if we fail to delete the dev extents we will abort since we can't have half of the dev extents hanging around, but this will make us much less likely to abort. Thanks, Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-02-20Btrfs: use seqlock to protect fs_info->avail_{data, metadata, system}_alloc_bitsMiao Xie
There is no lock to protect fs_info->avail_{data, metadata, system}_alloc_bits, it may introduce some problem, such as the wrong profile information, so we add a seqlock to protect them. Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com> Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-02-20Btrfs: make raid attr array more readableMiao Xie
The current code of raid attr arry is hard to understand and it is easy to introduce some problem if we modify the array. So I changed it and made it more readable. Cc: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-02-15btrfs: access superblock via pagecache in scan_one_deviceDavid Sterba
btrfs_scan_one_device is calling set_blocksize() which can race with a concurrent process making dirty page cache pages. It can end up dropping dirty page cache pages on the floor, which isn't very nice when someone is just running btrfs dev scan to find filesystems on the box. Now that udev is registering btrfs devices as it discovers them, we can actually end up racing with our own mkfs program too. When this happens, we drop some of the important blocks written by mkfs. This commit changes scan_one_device to read the super out of the page cache instead of trying to use bread. This way we don't have to care about the blocksize of the device. This also drops the invalidate_bdev() call. It wasn't very polite to invalidate during the scan either. mkfs is putting the super into the page cache, there's no reason to invalidate at this point. Signed-off-by: David Sterba <dsterba@suse.cz> Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-02-06Merge git://git.kernel.org/pub/scm/linux/kernel/git/josef/btrfs-next.git ↵Chris Mason
for-chris into for-linus
2013-02-05Merge branch 'for-linus' into raid56-experimentalChris Mason
Conflicts: fs/btrfs/volumes.c Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-02-05Btrfs: remove conflicting check for minimum number of devices in raid56Chris Mason
The device removal code was incorrectly checking against two different limits for raid5 and raid6. Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-02-01Btrfs: RAID5 and RAID6David Woodhouse
This builds on David Woodhouse's original Btrfs raid5/6 implementation. The code has changed quite a bit, blame Chris Mason for any bugs. Read/modify/write is done after the higher levels of the filesystem have prepared a given bio. This means the higher layers are not responsible for building full stripes, and they don't need to query for the topology of the extents that may get allocated during delayed allocation runs. It also means different files can easily share the same stripe. But, it does expose us to incorrect parity if we crash or lose power while doing a read/modify/write cycle. This will be addressed in a later commit. Scrub is unable to repair crc errors on raid5/6 chunks. Discard does not work on raid5/6 (yet) The stripe size is fixed at 64KiB per disk. This will be tunable in a later commit. Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-02-01btrfs: don't try to notify udev about missing devicesEric Sandeen
If we remove a missing device, bdev is null, and if we send that off to btrfs_kobject_uevent we'll panic. Signed-off-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com> Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-01-24Btrfs: fix wrong max device number for single profileMiao Xie
The max device number of single profile is 1, not 0 (0 means 'as many as possible'). Fix it. Cc: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Reviewed-by: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-01-22Btrfs: fix a regression in balance usage filterIlya Dryomov
Commit 3fed40cc ("Btrfs: cleanup duplicated division functions"), which was merged into 3.8-rc1, has introduced a regression by removing logic that was guarding us against bad user input. Bring it back. Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-01-20Btrfs: bring back balance pause/resume logicIlya Dryomov
Balance pause/resume logic got broken by 5ac00add (went in into 3.8-rc1 as part of dev-replace merge). Offending commit took a stab at making mutually exclusive volume operations (add_dev, rm_dev, resize, balance, replace_dev) not block behind volume_mutex if another such operation is in progress and instead return an error right away. Balancing front-end relied on the blocking behaviour, so the fix is ugly, but short of a complete rework, it's the best we can do. Reported-by: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2013-01-14btrfs: get the device in write mode when deleting itLukas Czerner
When we're deleting the device we should get it in write mode since we're going to re-write the super block magic on that device. And it should fail if the device is read-only. Signed-off-by: Lukas Czerner <lczerner@redhat.com>
2012-12-17Btrfs: put raid properties into global tableLiu Bo
Raid properties can be shared among raid calculation code, we can put them into a global table to keep it simple. Signed-off-by: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-17Btrfs: log changed inodes based on the extent map treeJosef Bacik
We don't really need to copy extents from the source tree since we have all of the information already available to us in the extent_map tree. So instead just write the extents straight to the log tree and don't bother to copy the extent items from the source tree. Signed-off-by: Josef Bacik <jbacik@fusionio.com> Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-17btrfs: Notify udev when removing deviceLukas Czerner
Currently udev does not know about the device being removed from the file system. This may result in the situation where we're unable to mount the file system by UUID or by LABEL because the by-uuid and by-label links may still point to the device which is no longer part of the btrfs file system and hence does not have any btrfs super block. It can be easily reproduced by the following: mkfs.btrfs -L bugfs /dev/loop[0-6] mount /dev/loop0 /mnt/test btrfs device delete /dev/loop0 /mnt/test umount /mnt/test mount LABEL=bugfs /mnt/test <---- this fails then see: ls -l /dev/disk/by-label/bugfs which will still point to the /dev/loop0 We did not noticed this before because libblkid would send the udev event for us when it notice that the link does not fit the reality, however it does not do that anymore and completely relies on udev information. Fix this by sending the KOBJ_CHANGE event to the bdev kobject after successful device removal. Note that this does not affect device addition, because we will open the device prior the addition from userspace and udev will notice that and reread the device afterwards. Signed-off-by: Lukas Czerner <lczerner@redhat.com> Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-17Btrfs: fix a build warning for an unused labelStefan Behrens
This issue was detected by the "0-DAY kernel build testing". fs/btrfs/volumes.c: In function 'btrfs_rm_device': fs/btrfs/volumes.c:1505:1: warning: label 'error_close' defined but not used [-Wunused-label] Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de> Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-12Btrfs: allow repair code to include target disk when searching mirrorsStefan Behrens
Make the target disk of a running device replace operation available for reading. This is only used as a last ressort for the defect repair procedure. And it is dependent on the location of the data block to read, because during an ongoing device replace operation, the target drive is only partially filled with the filesystem data. Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de> Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-12Btrfs: optionally avoid reads from device replace source driveStefan Behrens
It is desirable to be able to configure the device replace procedure to avoid reading the source drive (the one to be copied) whenever possible. This is useful when the number of read errors on this disk is high, because it would delay the copy procedure alot. Therefore there is an option to avoid reading from the source disk unless the repair procedure really needs to access it. The regular read req asks for mapping the block with mirror_num == 0, in this case the source disk is avoided whenever possible. The repair code selects the mirror_num explicitly (mirror_num != 0), this case is not changed by this commit. Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de> Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-12Btrfs: changes to live filesystem are also written to replacement diskStefan Behrens
During a running dev replace operation, all write requests to the live filesystem are duplicated to also write to the target drive. Therefore btrfs_map_block() is changed to duplicate stripes that are written to the source disk of a device replace procedure to be written to the target disk as well. Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de> Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-12Btrfs: introduce GET_READ_MIRRORS functionality for btrfs_map_block()Stefan Behrens
Before this commit, btrfs_map_block() was called with REQ_WRITE in order to retrieve the list of mirrors for a disk block. This needs to be changed for the device replace procedure since it makes a difference whether you are asking for read mirrors or for locations to write to. GET_READ_MIRRORS is introduced as a new interface to call btrfs_map_block(). In the current commit, the functionality is not yet changed, only the interface for GET_READ_MIRRORS is introduced and all the places that should use this new interface are adapted. The reason that REQ_WRITE cannot be abused anymore to retrieve a list of read mirrors is that during a running dev replace operation all write requests to the live filesystem are duplicated to also write to the target drive. Keep in mind that the target disk is only partially a valid copy of the source disk while the operation is ongoing. All writes go to the target disk, but not all reads would return valid data on the target disk. Therefore it is not possible anymore to abuse a REQ_WRITE interface to find valid mirrors for a REQ_READ. Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de> Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-12Btrfs: change core code of btrfs to support the device replace operationsStefan Behrens
This commit contains all the essential changes to the core code of Btrfs for support of the device replace procedure. Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de> Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-12Btrfs: add new sources for device replace codeStefan Behrens
This adds a new file to the sources together with the header file and the changes to ioctl.h and ctree.h that are required by the new C source file. Additionally, 4 new functions are added to volume.c that deal with device creation and destruction. Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de> Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-12Btrfs: handle errors from btrfs_map_bio() everywhereStefan Behrens
With the addition of the device replace procedure, it is possible for btrfs_map_bio(READ) to report an error. This happens when the specific mirror is requested which is located on the target disk, and the copy operation has not yet copied this block. Hence the block cannot be read and this error state is indicated by returning EIO. Some background information follows now. A new mirror is added while the device replace procedure is running. btrfs_get_num_copies() returns one more, and btrfs_map_bio(GET_READ_MIRROR) adds one more mirror if a disk location is involved that was already handled by the device replace copy operation. The assigned mirror num is the highest mirror number, e.g. the value 3 in case of RAID1. If btrfs_map_bio() is invoked with mirror_num == 0 (i.e., select any mirror), the copy on the target drive is never selected because that disk shall be able to perform the write requests as quickly as possible. The parallel execution of read requests would only slow down the disk copy procedure. Second case is that btrfs_map_bio() is called with mirror_num > 0. This is done from the repair code only. In this case, the highest mirror num is assigned to the target disk, since it is used last. And when this mirror is not available because the copy procedure has not yet handled this area, an error is returned. Everywhere in the code the handling of such errors is added now. Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de> Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-12Btrfs: disallow some operations on the device replace target deviceStefan Behrens
This patch adds some code to disallow operations on the device that is used as the target for the device replace operation. Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de> Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-12Btrfs: disallow mutually exclusive admin operations from user modeStefan Behrens
Btrfs admin operations that are manually started from user mode and that cannot be executed at the same time return -EINPROGRESS. A common way to enter and leave this locked section is introduced since it used to be specific to the balance operation. Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de> Signed-off-by: Chris Mason <chris.mason@fusionio.com>