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2010-03-23ceph: prevent dup stale messages to console for restarting mdsSage Weil
Prevent duplicate 'mds0 caps stale' message from spamming the console every few seconds while the MDS restarts. Set s_renew_requested earlier, so that we only print the message once, even if we don't send an actual request. Signed-off-by: Sage Weil <sage@newdream.net>
2010-03-23ceph: fix pg pool decoding from incremental osdmap updateSage Weil
The incremental map decoding of pg pool updates wasn't skipping the snaps and removed_snaps vectors. This caused osd requests to stall when pool snapshots were created or fs snapshots were deleted. Use a common helper for full and incremental map decoders that decodes pools properly. Signed-off-by: Sage Weil <sage@newdream.net>
2010-03-23ceph: fix mds sync() race with completing requestsSage Weil
The wait_unsafe_requests() helper dropped the mdsc mutex to wait for each request to complete, and then examined r_node to get the next request after retaking the lock. But the request completion removes the request from the tree, so r_node was always undefined at this point. Since it's a small race, it usually led to a valid request, but not always. The result was an occasional crash in rb_next() while dereferencing node->rb_left. Fix this by clearing the rb_node when removing the request from the request tree, and not walking off into the weeds when we are done waiting for a request. Since the request we waited on will _always_ be out of the request tree, take a ref on the next request, in the hopes that it won't be. But if it is, it's ok: we can start over from the beginning (and traverse over older read requests again). Signed-off-by: Sage Weil <sage@newdream.net>
2010-03-23ceph: only release unused caps with mds requestsSage Weil
We were releasing used caps (e.g. FILE_CACHE) from encode_inode_release with MDS requests (e.g. setattr). We don't carry refs on most caps, so this code worked most of the time, but for setattr (utimes) we try to drop Fscr. This causes cap state to get slightly out of sync with reality, and may result in subsequent mds revoke messages getting ignored. Fix by only releasing unused caps. Signed-off-by: Sage Weil <sage@newdream.net>
2010-03-23ceph: clean up handle_cap_grant, handle_caps wrt session mutexSage Weil
Drop session mutex unconditionally in handle_cap_grant, and do the check_caps from the handle_cap_grant helper. This avoids using a magic return value. Also avoid using a flag variable in the IMPORT case and call check_caps at the appropriate point. Signed-off-by: Sage Weil <sage@newdream.net>
2010-03-23ceph: fix session locking in handle_caps, ceph_check_capsSage Weil
Passing a session pointer to ceph_check_caps() used to mean it would leave the session mutex locked. That wasn't always possible if it wasn't passed CHECK_CAPS_AUTHONLY. If could unlock the passed session and lock a differet session mutex, which was clearly wrong, and also emitted a warning when it a racing CPU retook it and we did an unlock from the wrong context. This was only a problem when there was more than one MDS. First, make ceph_check_caps unconditionally drop the session mutex, so that it is free to lock other sessions as needed. Then adjust the one caller that passes in a session (handle_cap_grant) accordingly. Signed-off-by: Sage Weil <sage@newdream.net>
2010-03-23ceph: drop unnecessary WARN_ON in caps migrationSage Weil
If we don't have the exported cap it's because we already released it. No need to WARN. Signed-off-by: Sage Weil <sage@newdream.net>
2010-03-23ceph: fix null pointer deref of r_osd in debug outputSage Weil
This causes an oops when debug output is enabled and we kick an osd request with no current r_osd (sometime after an osd failure). Check the pointer before dereferencing. Signed-off-by: Sage Weil <sage@newdream.net>
2010-03-23ceph: clean up service ticket decodingSage Weil
Previously we would decode state directly into our current ticket_handler. This is problematic if for some reason we fail to decode, because we end up with half new state and half old state. We are probably already in bad shape if we get an update we can't decode, but we may as well be tidy anyway. Decode into new_* temporaries and update the ticket_handler only on success. Signed-off-by: Sage Weil <sage@newdream.net>
2010-03-22AFS: Potential null dereferenceDan Carpenter
It seems clear from the surrounding code that xpermits is allowed to be NULL here. Signed-off-by: Dan Carpenter <error27@gmail.com> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-22NFS: don't try to decode GETATTR if DELEGRETURN returned errorJeff Layton
The reply parsing code attempts to decode the GETATTR response even if the DELEGRETURN portion of the compound returned an error. The GETATTR response won't actually exist if that's the case and we're asking the parser to read past the end of the response. This bug is fairly benign. The parser catches this without reading past the end of the response and decode_getfattr returns -EIO. Earlier kernels however had decode_op_hdr using the READ_BUF macro, and this bug would make this printk pop any time the client got an error from a delegreturn: kernel: decode_op_hdr: reply buffer overflowed in line XXXX More recent kernels seem to have replaced this printk with a dprintk. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-03-22nilfs2: fix duplicate call to nilfs_segctor_cancel_freevRyusuke Konishi
Andreas Beckmann gave me a report that nilfs logged the following warnings when it got a disk full: nilfs_sufile_do_cancel_free: segment 0 must be clean nilfs_sufile_do_cancel_free: segment 1 must be clean These arise from a duplicate call to nilfs_segctor_cancel_freev in an error path of log writer. This will fix the issue. Reported-by: Andreas Beckmann <debian@abeckmann.de> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2010-03-20ceph: release old ticket_blob bufferSage Weil
Release the old ticket_blob buffer when we get an updated service ticket from the monitor. Previously these were getting leaked. Signed-off-by: Sage Weil <sage@newdream.net>
2010-03-20ceph: fix authenticator buffer size calculationSage Weil
The buffer size was incorrectly calculated for the ceph_x_encrypt() encapsulated ticket blob. Use a helper (with correct arithmetic) and BUG out if we were wrong. Signed-off-by: Sage Weil <sage@newdream.net>
2010-03-20ceph: fix authenticator timeoutSage Weil
We were failing to reconnect to services due to an old authenticator, even though we had the new ticket, because we weren't properly retrying the connect handshake, because we were calling an old/incorrect helper that left in_base_pos incorrect. The result was a failure to reconnect to the OSD or MDS (with an authentication error) if the MDS restarted after the service had been up a few hours (long enough for the original authenticator to be invalid). This was only a problem if the AUTH_X authentication was enabled. Now that the 'negotiate' and 'connect' stages are fully separated, we should use the prepare_read_connect() helper instead, and remove the obsolete one. Signed-off-by: Sage Weil <sage@newdream.net>
2010-03-20ceph: fix inode removal from snap realm when racing with migrationSage Weil
When an inode was dropped while being migrated between two MDSs, i_cap_exporting_issued was non-zero such that issue caps were non-zero and __ceph_is_any_caps(ci) was true. This prevented the inode from being removed from the snap realm, even as it was dropped from the cache. Fix this by dropping any residual i_snap_realm ref in destroy_inode. Signed-off-by: Sage Weil <sage@newdream.net>
2010-03-20ceph: add missing locking to protect i_snap_realm_item during splitSage Weil
All ci->i_snap_realm_item/realm->inodes_with_caps manipulation should be protected by realm->inodes_with_caps_lock. This bug would have only bit us in a rare race with a realm split (during some snap creations). Signed-off-by: Sage Weil <sage@newdream.net>
2010-03-20ceph: implemented caps should always be superset of issued capsSage Weil
Added assertion, and cleared one case where the implemented caps were not following the issued caps. Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net> Signed-off-by: Sage Weil <sage@newdream.net>
2010-03-19ocfs2: Init meta_ac properly in ocfs2_create_empty_xattr_block.Tao Ma
You can't store a pointer that you haven't filled in yet and expect it to work. Signed-off-by: Tao Ma <tao.ma@oracle.com> Signed-off-by: Joel Becker <joel.becker@oracle.com>
2010-03-19ocfs2: Fix the update of name_offset when removing xattrsTao Ma
When replacing a xattr's value, in some case we wipe its name/value first and then re-add it. The wipe is done by ocfs2_xa_block_wipe_namevalue() when the xattr is in the inode or block. We currently adjust name_offset for all the entries which have (offset < name_offset). This does not adjust the entrie we're replacing. Since we are replacing the entry, we don't adjust the total entry count. When we calculate a new namevalue location, we trust the entries now-wrong offset in ocfs2_xa_get_free_start(). The solution is to also adjust the name_offset for the replaced entry, allowing ocfs2_xa_get_free_start() to calculate the new namevalue location correctly. The following script can trigger a kernel panic easily. echo 'y'|mkfs.ocfs2 --fs-features=local,xattr -b 4K $DEVICE mount -t ocfs2 $DEVICE $MNT_DIR FILE=$MNT_DIR/$RANDOM for((i=0;i<76;i++)) do string_76="a$string_76" done string_78="aa$string_76" string_82="aaaa$string_78" touch $FILE setfattr -n 'user.test1234567890' -v $string_76 $FILE setfattr -n 'user.test1234567890' -v $string_78 $FILE setfattr -n 'user.test1234567890' -v $string_82 $FILE Signed-off-by: Tao Ma <tao.ma@oracle.com> Signed-off-by: Joel Becker <joel.becker@oracle.com>
2010-03-19NFS: Prevent another deadlock in nfs_release_page()Trond Myklebust
We should not attempt to free the page if __GFP_FS is not set. Otherwise we can deadlock as per http://bugzilla.kernel.org/show_bug.cgi?id=15578 Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> Cc: stable@kernel.org
2010-03-19Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client: (205 commits) ceph: update for write_inode API change ceph: reset osd after relevant messages timed out ceph: fix flush_dirty_caps race with caps migration ceph: include migrating caps in issued set ceph: fix osdmap decoding when pools include (removed) snaps ceph: return EBADF if waiting for caps on closed file ceph: set osd request message front length correctly ceph: reset front len on return to msgpool; BUG on mismatched front iov ceph: fix snaptrace decoding on cap migration between mds ceph: use single osd op reply msg ceph: reset bits on connection close ceph: remove bogus mds forward warning ceph: remove fragile __map_osds optimization ceph: fix connection fault STANDBY check ceph: invalidate_authorizer without con->mutex held ceph: don't clobber write return value when using O_SYNC ceph: fix client_request_forward decoding ceph: drop messages on unregistered mds sessions; cleanup ceph: fix comments, locking in destroy_inode ceph: move dereference after NULL test ... Fix trivial conflicts in Documentation/ioctl/ioctl-number.txt
2010-03-19Merge git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6Linus Torvalds
* git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6: cifs: trivial white space [CIFS] checkpatch cleanup cifs: add cifs_revalidate_file cifs: add a CIFSSMBUnixQFileInfo function cifs: add a CIFSSMBQFileInfo function cifs: overhaul cifs_revalidate and rename to cifs_revalidate_dentry
2010-03-18Merge git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstableLinus Torvalds
* git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable: (30 commits) Btrfs: fix the inode ref searches done by btrfs_search_path_in_tree Btrfs: allow treeid==0 in the inode lookup ioctl Btrfs: return keys for large items to the search ioctl Btrfs: fix key checks and advance in the search ioctl Btrfs: buffer results in the space_info ioctl Btrfs: use __u64 types in ioctl.h Btrfs: fix search_ioctl key advance Btrfs: fix gfp flags masking in the compression code Btrfs: don't look at bio flags after submit_bio btrfs: using btrfs_stack_device_id() get devid btrfs: use memparse Btrfs: add a "df" ioctl for btrfs Btrfs: cache the extent state everywhere we possibly can V2 Btrfs: cache ordered extent when completing io Btrfs: cache extent state in find_delalloc_range Btrfs: change the ordered tree to use a spinlock instead of a mutex Btrfs: finish read pages in the order they are submitted btrfs: fix btrfs_mkdir goto for no free objectids Btrfs: flush data on snapshot creation Btrfs: make df be a little bit more understandable ...
2010-03-18Merge branch 'bugfixes' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6Linus Torvalds
* 'bugfixes' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6: NFS: ensure bdi_unregister is called on mount failure. NFS: Avoid a deadlock in nfs_release_page NFSv4: Don't ignore the NFS_INO_REVAL_FORCED flag in nfs_revalidate_inode() nfs4: Make the v4 callback service hidden nfs: fix unlikely memory leak rpc client can not deal with ENOSOCK, so translate it into ENOCONN
2010-03-18Merge branch 'for-linus' of git://oss.sgi.com/xfs/xfsLinus Torvalds
* 'for-linus' of git://oss.sgi.com/xfs/xfs: xfs: don't warn about page discards on shutdown xfs: use scalable vmap API xfs: remove old vmap cache
2010-03-18ocfs2: Always try for maximum bits with new local alloc windowsMark Fasheh
What we were doing before was to ask for the current window size as the maximum allocation. This had the effect of limiting the amount of allocation we could get for the local alloc during times when the window size was shrunk due to fragmentation. In some cases, that could actually *increase* fragmentation by artificially limiting the number of bits we can accept. So while we still want to ask for a minimum number of bits equal to window size, there is no reason why we should limit the number of bits the local alloc should accept. Hence always allow the maximum number of local alloc bits. Signed-off-by: Mark Fasheh <mfasheh@suse.com> Signed-off-by: Joel Becker <joel.becker@oracle.com>
2010-03-18Btrfs: fix the inode ref searches done by btrfs_search_path_in_treeChris Mason
This is used by the inode lookup ioctl to follow all the backrefs up to the subvol root. But the search being done would sometimes land one past the last item in the leaf instead of finding the backref. This changes the search to look for the highest possible backref and hop back one item. It also fixes a leaked path on failure to find the root. Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-03-18Btrfs: allow treeid==0 in the inode lookup ioctlChris Mason
When a root id of 0 is sent to the inode lookup ioctl, it will use the root of the file we're ioctling and pass the root id back to userland along with the results. This allows userland to do searches based on that root later on. Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-03-18Btrfs: return keys for large items to the search ioctlChris Mason
The search ioctl was skipping large items entirely (ones that are too big for the results buffer). This changes things to at least copy the item header so that we can send information about the item back to userland. Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-03-18Btrfs: fix key checks and advance in the search ioctlChris Mason
The search ioctl was working well for finding tree roots, but using it for generic searches requires a few changes to how the keys are advanced. This treats the search control min fields for objectid, type and offset more like a key, where we drop the offset to zero once we bump the type, etc. The downside of this is that we are changing the min_type and min_offset fields during the search, and so the ioctl caller needs extra checks to make sure the keys in the result are the ones it wanted. This also changes key_in_sk to use btrfs_comp_cpu_keys, just to make things more readable. Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-03-17ntfs: use bitmap_weightAkinobu Mita
Use bitmap_weight() instead of doing hweight32() for each u32 element in the page. Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: Anton Altaparmakov <aia21@cantab.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-17jffs2: fix up rb_root initializations to use RB_ROOTVenkatesh Pallipadi
jffs2 uses rb_node = NULL; to zero rb_root. The problem with this is that 17d9ddc72fb8bba0d4f678 ("rbtree: Add support for augmented rbtrees") in the linux-next tree adds a new field to that struct which needs to be NULL as well. This patch uses RB_ROOT as the intializer so all of the relevant fields will be NULL'd. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Cc: Eric Paris <eparis@redhat.com> Acked-by: David Woodhouse <dwmw2@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-17ocfs2: set i_mode on disk during acl operationsMark Fasheh
ocfs2_set_acl() and ocfs2_init_acl() were setting i_mode on the in-memory inode, but never setting it on the disk copy. Thus, acls were some times not getting propagated between nodes. This patch fixes the issue by adding a helper function ocfs2_acl_set_mode() which does this the right way. ocfs2_set_acl() and ocfs2_init_acl() are then updated to call ocfs2_acl_set_mode(). Signed-off-by: Mark Fasheh <mfasheh@suse.com> Signed-off-by: Joel Becker <joel.becker@oracle.com>
2010-03-17ocfs2: Update i_blocks in reflink operations.Tao Ma
In reflink, we need to upate i_blocks for the target inode. Reported-by: Jie Liu <jeff.liu@oracle.com> Signed-off-by: Tao Ma <tao.ma@oracle.com> Signed-off-by: Joel Becker <joel.becker@oracle.com>
2010-03-17ocfs2: Change bg_chain check for ocfs2_validate_gd_parent.Tao Ma
In ocfs2_validate_gd_parent, we check bg_chain against the cl_next_free_rec of the dinode. Actually in resize, we have the chance of bg_chain == cl_next_free_rec. So add some additional condition check for it. I also rename paramter "clean_error" to "resize", since the old one is not clearly enough to indicate that we should only meet with this case in resize. btw, the correpsonding bug is http://oss.oracle.com/bugzilla/show_bug.cgi?id=1230. Signed-off-by: Tao Ma <tao.ma@oracle.com> Signed-off-by: Joel Becker <joel.becker@oracle.com>
2010-03-17[PATCH] Skip check for mandatory locks when unlockingSachin Prabhu
ocfs2_lock() will skip locks on file which has mode set to 02666. This is a problem in cases where the mode of the file is changed after a process has obtained a lock on the file. ocfs2_lock() should skip the check for mandatory locks when unlocking a file. Signed-off-by: Sachin Prabhu <sprabhu@redhat.com> Signed-off-by: Joel Becker <joel.becker@oracle.com>
2010-03-16xfs: don't warn about page discards on shutdownDave Chinner
If we are doing a forced shutdown, we can get lots of noise about delalloc pages being discarded. This is happens by design during a forced shutdown, so don't spam the logs with these messages. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
2010-03-16xfs: use scalable vmap APIAlex Elder
Re-apply a commit that had been reverted due to regressions that have since been fixed. From 95f8e302c04c0b0c6de35ab399a5551605eeb006 Mon Sep 17 00:00:00 2001 From: Nick Piggin <npiggin@suse.de> Date: Tue, 6 Jan 2009 14:43:09 +1100 Implement XFS's large buffer support with the new vmap APIs. See the vmap rewrite (db64fe02) for some numbers. The biggest improvement that comes from using the new APIs is avoiding the global KVA allocation lock on every call. Signed-off-by: Nick Piggin <npiggin@suse.de> Reviewed-by: Christoph Hellwig <hch@infradead.org> Signed-off-by: Lachlan McIlroy <lachlan@sgi.com> Only modifications here were a minor reformat, plus making the patch apply given the new use of xfs_buf_is_vmapped(). Modified-by: Alex Elder <aelder@sgi.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
2010-03-16xfs: remove old vmap cacheAlex Elder
Re-apply a commit that had been reverted due to regressions that have since been fixed. Original commit: d2859751cd0bf586941ffa7308635a293f943c17 Author: Nick Piggin <npiggin@suse.de> Date: Tue, 6 Jan 2009 14:40:44 +1100 XFS's vmap batching simply defers a number (up to 64) of vunmaps, and keeps track of them in a list. To purge the batch, it just goes through the list and calls vunamp on each one. This is pretty poor: a global TLB flush is generally still performed on each vunmap, with the most expensive parts of the operation being the broadcast IPIs and locking involved in the SMP callouts, and the locking involved in the vmap management -- none of these are avoided by just batching up the calls. I'm actually surprised it ever made much difference. (Now that the lazy vmap allocator is upstream, this description is not quite right, but the vunmap batching still doesn't seem to do much). Rip all this logic out of XFS completely. I will improve vmap performance and scalability directly in subsequent patch. Signed-off-by: Nick Piggin <npiggin@suse.de> Reviewed-by: Christoph Hellwig <hch@infradead.org> Signed-off-by: Lachlan McIlroy <lachlan@sgi.com> The only change I made was to use the "new" xfs_buf_is_vmapped() function in a place it had been open-coded in the original. Modified-by: Alex Elder <aelder@sgi.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
2010-03-16Btrfs: buffer results in the space_info ioctlChris Mason
The space_info ioctl was using copy_to_user inside rcu_read_lock. This commit changes things to copy into a buffer first and then dump the result down to userland. Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-03-16Btrfs: use __u64 types in ioctl.hSage Weil
Signed-off-by: Sage Weil <sage@newdream.net> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-03-16Btrfs: fix search_ioctl key advanceSage Weil
key->type is u8, not u64. fs/btrfs/ioctl.c: In function 'copy_to_sk': fs/btrfs/ioctl.c:1024: warning: comparison is always true due to limited range of data type Signed-off-by: Sage Weil <sage@newdream.net> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-03-15NFS: ensure bdi_unregister is called on mount failure.NeilBrown
bdi_unregister is called by nfs_put_super which is only called by generic_shutdown_super if ->s_root is not NULL. So if we error out in a circumstance where we called nfs_bdi_register (i.e. server != NULL) but have not set s_root, then we need to call bdi_unregister explicitly in nfs_get_sb and various other *_get_sb() functions. Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-03-15cifs: trivial white spaceDan Carpenter
I fixed the indent level. Signed-off-by: Dan Carpenter <error27@gmail.com> Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-03-15Btrfs: fix gfp flags masking in the compression codeNick Piggin
GFP_FS must be masked out, NOFS can't be or'd in. Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-03-15Btrfs: don't look at bio flags after submit_bioChris Mason
After callling submit_bio, the bio can be freed at any time. The btrfs submission thread helper was checking the bio flags too late, which might not give the correct answer. When CONFIG_DEBUG_PAGE_ALLOC is turned on, it can lead to oopsen. Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-03-15btrfs: using btrfs_stack_device_id() get devidXiao Guangrong
We can use btrfs_stack_device_id() to get dev_item->devid Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-03-15btrfs: use memparseAkinobu Mita
Use memparse() instead of its own private implementation. Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: Chris Mason <chris.mason@oracle.com> Cc: linux-btrfs@vger.kernel.org Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-03-15Btrfs: add a "df" ioctl for btrfsJosef Bacik
df is a very loaded question in btrfs. This gives us a way to get the per-space usage information so we can tell exactly what is in use where. This will help us figure out ENOSPC problems, and help users better understand where their disk space is going. Signed-off-by: Josef Bacik <josef@redhat.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>