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path: root/fs/btrfs/backref.c
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2013-02-26Btrfs: fix backref walking race with tree deletionsJan Schmidt
When a subvolume is removed, we remove the root item from the root tree, while the tree blocks and backrefs remain for a while. When backref walking comes across one of those orphan tree blocks, it can find a backref for a no longer existing root. This is all good, we only must tolerate __resolve_indirect_ref returning an error and continue with the good refs found. Reported-by: Alex Lyakas <alex.btrfs@zadarastorage.com> Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2012-12-12Btrfs: merge inode_list in __merge_refsAlexander Block
When __merge_refs merges two refs, it is also needed to merge the inode_list of both refs. Otherwise we have missed backrefs and memory leaks. This happens for example if two inodes share an extent and both lie in the same leaf and thus also have the same parent. Signed-off-by: Alexander Block <ablock84@googlemail.com> Reviewed-by: Jan Schmidt <list.btrfs@jan-o-sch.net> Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-12fs/btrfs: drop if around WARN_ONJulia Lawall
Just use WARN_ON rather than an if containing only WARN_ON(1). A simplified version of the semantic patch that makes this transformation is as follows: (http://coccinelle.lip6.fr/) // <smpl> @@ expression e; @@ - if (e) WARN_ON(1); + WARN_ON(e); // </smpl> Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr> Reviewed-by: David Sterba <dsterba@suse.cz> Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-10-25Merge branch 'for-chris-fixed' of git://git.jan-o-sch.net/btrfs-unstableChris Mason
2012-10-25Btrfs: extended inode refs support for send mechanismJan Schmidt
This adds support for the new extended inode refs to btrfs send. Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2012-10-25Fix a sign bug causing invalid memory access in the ino_paths ioctl.Gabriel de Perthuis
To see the problem, create many hardlinks to the same file (120 should do it), then look up paths by inode with: ls -i btrfs inspect inode-resolve -v $ino /mnt/btrfs I noticed the memory layout of the fspath->val data had some irregularities (some unnecessary gaps that stop appearing about halfway), so I'm not sure there aren't any bugs left in it.
2012-10-24Btrfs: determine level of old rootsJan Schmidt
In btrfs_find_all_roots' termination condition, we compare the level of the old buffer we got from btrfs_search_old_slot to the level of the current root node. We'd better compare it to the level of the rewinded root node. Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2012-10-09btrfs: extended inode ref iterationMark Fasheh
The iterate_irefs in backref.c is used to build path components from inode refs. This patch adds code to iterate extended refs as well. I had modify the callback function signature to abstract out some of the differences between ref structures. iref_to_path() also needed similar changes. Signed-off-by: Mark Fasheh <mfasheh@suse.de>
2012-10-09btrfs: extended inode refsMark Fasheh
This patch adds basic support for extended inode refs. This includes support for link and unlink of the refs, which basically gets us support for rename as well. Inode creation does not need changing - extended refs are only added after the ref array is full. Signed-off-by: Mark Fasheh <mfasheh@suse.de>
2012-10-01Btrfs: use larger limit for translation of logical to inodeLiu Bo
This is the change of the kernel side. Translation of logical to inode used to have an upper limit 4k on inode container's size, but the limit is not large enough for a data with a great many of refs, so when resolving logical address, we can end up with "ioctl ret=0, bytes_left=0, bytes_missing=19944, cnt=510, missed=2493" This changes to regard 64k as the upper limit and use vmalloc instead of kmalloc to get memory more easily. Signed-off-by: Josef Bacik <jbacik@fusionio.com> Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
2012-10-01Btrfs: fix a bug in parsing return value in logical resolveLiu Bo
In logical resolve, we parse extent_from_logical()'s 'ret' as a kind of flag. It is possible to lose our errors because (-EXXXX & BTRFS_EXTENT_FLAG_TREE_BLOCK) is true. I'm not sure if it is on purpose, it just looks too hacky if it is. I'd rather use a real flag and a 'ret' to catch errors. Acked-by: Jan Schmidt <list.btrfs@jan-o-sch.net> Signed-off-by: Liu Bo <liub.liubo@gmail.com>
2012-10-01Btrfs: fix gcc warnings for 32bit compilesJan Schmidt
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net> Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-10-01Btrfs: make aux field of ulist 64 bitAlexander Block
Btrfs send/receive uses the aux field to store inode numbers. On 32 bit machines this may become a problem. Also fix all users of ulist_add and ulist_add_merged. Reported-by: Arne Jansen <sensille@gmx.net> Signed-off-by: Alexander Block <ablock84@googlemail.com>
2012-08-28Btrfs: fix that error value is changed by mistakeStefan Behrens
In iterate_inodes_from_logical() the error result from extent_from_logical() is patched by mistake. Typically ENOENT is patched to EINVAL because (-ENOENT & BTRFS_EXTENT_FLAG_TREE_BLOCK) evaluates to true. Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
2012-07-25Merge branch 'send-v2' of git://github.com/ablock84/linux-btrfs into for-linusChris Mason
This is the kernel portion of btrfs send/receive Conflicts: fs/btrfs/Makefile fs/btrfs/backref.h fs/btrfs/ctree.c fs/btrfs/ioctl.c fs/btrfs/ioctl.h Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-07-25Btrfs: make iref_to_path non staticAlexander Block
Make iref_to_path non static (needed in send) and rename it to btrfs_iref_to_path Signed-off-by: Alexander Block <ablock84@googlemail.com>
2012-07-10Btrfs: join tree mod log code with the code holding back delayed refsJan Schmidt
We've got two mechanisms both required for reliable backref resolving (tree mod log and holding back delayed refs). You cannot make use of one without the other. So instead of requiring the user of this mechanism to setup both correctly, we join them into a single interface. Additionally, we stop inserting non-blockers into fs_info->tree_mod_seq_list as we did before, which was of no value. Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2012-06-27Btrfs: leave critical region in btrfs_find_all_roots as soon as possibleJan Schmidt
When delayed refs exist, btrfs_find_all_roots used to hold the delayed ref mutex way longer than actually required. We ought to drop it immediately after we're done collecting all the delayed refs. Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2012-06-27Btrfs: support root level changes in __resolve_indirect_refJan Schmidt
With the tree mod log, we can have a tree that's two levels high, but btrfs_search_old_slot may still return a path with the tree root at level one instead. __resolve_indirect_ref must care for this and accept parents in a lower level than expected. Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2012-06-21Btrfs: don't assume to be on the correct extent in add_all_parentsAlexander Block
add_all_parents did assume that path is already at a correct extent data item, which may not be true in case of data extents that were partly rewritten and splitted. We need to check if we're on a matching extent for every item and only for the ones after the first. The loop is changed to do this now. This patch also fixes a bug introduced with commit 3b127fd8 "Btrfs: remove obsolete btrfs_next_leaf call from __resolve_indirect_ref". The removal of next_leaf did sometimes result in slot==nritems when the above described case happens, and thus resulting in invalid values (e.g. wanted_obejctid) in add_all_parents (leading to missed backrefs or even crashes). Signed-off-by: Alexander Block <ablock84@googlemail.com> Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net> Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-06-14Btrfs: add btrfs_next_old_leafJan Schmidt
To make sense of the tree mod log, the backref walker not only needs btrfs_search_old_slot, but it also called btrfs_next_leaf, which in turn was calling btrfs_search_slot. This obviously didn't give the correct result. This commit adds btrfs_next_old_leaf, a drop-in replacement for btrfs_next_leaf with a time_seq parameter. If it is zero, it behaves exactly like btrfs_next_leaf. If it is non-zero, it will use btrfs_search_old_slot with this time_seq parameter. Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2012-06-14Btrfs: remove obsolete btrfs_next_leaf call from __resolve_indirect_refJan Schmidt
When resolving indirect refs, we used to call btrfs_next_leaf in case we didn't find an exact match. While we should find exact matches most of the time, in case we don't, we must continue searching. Treating those matches differently depending on the level we're searching doesn't make sense. Even worse, we might end up searching for a key larger than the largest, in which case there is no next_leaf and subsequent jobs would fail. This commit drops the bogous lines. Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2012-05-31Btrfs: add inodes before dropping the extent lock in find_all_leafsJan Schmidt
We must build up the inode list with the extent lock held after following indirect refs. This also requires an extension to ulists, which allows to modify the stored aux value in case a key already exists in the list. Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2012-05-30Btrfs: use the tree modification log for backref resolvingJan Schmidt
This enables backref resolving on life trees while they are changing. This is a prerequisite for quota groups and just nice to have for everything else. Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2012-05-26Btrfs: look into the extent during find_all_leafsJan Schmidt
Before this patch we called find_all_leafs for a data extent, then called find_all_roots and then looked into the extent to grab the information we were seeking. This was done without holding the leaves locked to avoid deadlocks. However, this can obviouly race with concurrent tree modifications. Instead, we now look into the extent while we're holding the lock during find_all_leafs and store this information together with the leaf list. Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2012-05-26Btrfs: bugfix: ignore the wrong key for indirect tree block backrefsJan Schmidt
The key we store with a tree block backref is only a hint. It is set when the ref is created and can remain correct for a long time. As the tree is rebalanced, however, eventually the key no longer points to the correct destination. With this patch, we change find_parent_nodes to no longer add keys unless it knows for sure they're correct (e.g. because they're for an extent data backref). Then when we later encounter a backref ref with no parent and no key set, we grab the block and take the first key from the block itself. Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2012-05-26Btrfs: bugfix in btrfs_find_parent_nodesJan Schmidt
That one has been around since the addition of backref.c. Due to the way we calculate our slot numbers, after adding inline refs we're missing one keyed ref unless it's located at the beginning of a new leaf. Reported-by: Alexander Block <ablock84@googlemail.com> Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2012-05-26Btrfs: ulist realloc bugfixJan Schmidt
ulist_next gets the pointer to the previously returned element to find the next element from there. However, when we call ulist_add while iteration with ulist_next is in progress (ulist explicitly supports this), we can realloc the ulist internal memory, which makes the pointer to the previous element useless. Instead, we now use an iterator parameter that's independent from the internal pointers. Reported-by: Alexander Block <ablock84@googlemail.com> Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2012-04-18Btrfs: add missing read locks in backref.cJan Schmidt
iref_to_path and iterate_irefs both increment the eb's refcount to use it after releasing the path. Both depend on consistent data remaining in the extent buffer and need a read lock to protect it. Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2012-04-18Btrfs: don't call free_extent_buffer twice in iterate_irefsJan Schmidt
Avoid calling free_extent_buffer more than once when the iterator function returns non-zero. The only code that uses this is scrub repair for corrupted nodatasum blocks. Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2012-04-18Btrfs: Make free_ipath() deal gracefully with NULL pointersJesper Juhl
Make free_ipath() behave like most other freeing functions in the kernel and gracefully do nothing when passed a NULL pointer. Besides this making the bahaviour consistent with functions such as kfree(), vfree(), btrfs_free_path() etc etc, it also fixes a real NULL deref issue in fs/btrfs/ioctl.c::btrfs_ioctl_ino_to_path(). In that function we have this code: ... ipath = init_ipath(size, root, path); if (IS_ERR(ipath)) { ret = PTR_ERR(ipath); ipath = NULL; goto out; } ... out: btrfs_free_path(path); free_ipath(ipath); ... If we ever take the true branch of that 'if' statement we'll end up passing a NULL pointer to free_ipath() which will subsequently dereference it and we'll go "Boom" :-( This patch will avoid that. Signed-off-by: Jesper Juhl <jj@chaosbits.net>
2012-03-28Merge git://git.jan-o-sch.net/btrfs-unstable into for-linusChris Mason
Conflicts: fs/btrfs/transaction.c Signed-off-by: Chris Mason <chris.mason@oracle.com>
2012-03-27Btrfs: fix memory leak in resolver codeIlya Dryomov
init_ipath() allocates btrfs_data_container which is never freed. Free it in free_ipath() and nuke the comment for init_data_container() - we can safely free it with kfree(). Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2012-03-27Btrfs: fix regression in scrub path resolvingJan Schmidt
In commit 4692cf58 we introduced new backref walking code for btrfs. This assumes we're searching live roots, which requires a transaction context. While scrubbing, however, we must not join a transaction because this could deadlock with the commit path. Additionally, what scrub really wants to do is resolving a logical address in the commit root it's currently checking. This patch adds support for logical to path resolving on commit roots and makes scrub use that. Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2012-03-03btrfs: fix locking issues in find_parent_nodes()Li Zefan
- We might unlock head->mutex while it was not locked - We might leave the function without unlocking delayed_refs->lock Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2012-02-15Btrfs: avoid positive number with ERR_PTRJan Schmidt
inode_ref_info() returns 1 when the element wasn't found and < 0 on error, just like btrfs_search_slot(). In iref_to_path() it's an error when the inode ref can't be found, thus we return ERR_PTR(ret) in that case. In order to avoid ERR_PTR(1), we now set ret to -ENOENT in that case. Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2012-01-26Btrfs: fix uninit warning in backref.cJan Schmidt
Added initialization with the declaration of ret. It isn't set later on the switch-default branch (which should never be taken). Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2012-01-05Btrfs: new backref walking codeJan Schmidt
The old backref iteration code could only safely be used on commit roots. Besides this limitation, it had bugs in finding the roots for these references. This commit replaces large parts of it by btrfs_find_all_roots() which a) really finds all roots and the correct roots, b) works correctly under heavy file system load, c) considers delayed refs. Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2012-01-04Btrfs: added btrfs_find_all_roots()Jan Schmidt
This function gets a byte number (a data extent), collects all the leafs pointing to it and walks up the trees to find all fs roots pointing to those leafs. It also returns the list of all leafs pointing to that extent. It does proper locking for the involved trees, can be used on busy file systems and honors delayed refs. Signed-off-by: Arne Jansen <sensille@gmx.net> Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2011-11-20btrfs: Fix up 32/64-bit compatibility for new ioctlsJeff Mahoney
This patch casts to unsigned long before casting to a pointer and fixes the following warnings: fs/btrfs/extent_io.c:2289:20: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast] fs/btrfs/ioctl.c:2933:37: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast] fs/btrfs/ioctl.c:2937:21: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast] fs/btrfs/ioctl.c:3020:21: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast] fs/btrfs/scrub.c:275:4: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast] fs/btrfs/backref.c:686:27: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast] Signed-off-by: Jeff Mahoney <jeffm@suse.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-11-06Btrfs: fix the new inspection ioctls for 32 bit compatChris Mason
The new ioctls to follow backrefs are not clean for 32/64 bit compat. This reworks them for u64s everywhere. They are brand new, so there are no problems with changing the interface now. Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-09-29btrfs: added helper functions to iterate backrefsJan Schmidt
These helper functions iterate back references and call a function for each backref. There is also a function to resolve an inode to a path in the file system. Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>