Commit Graph

42603 Commits

Author SHA1 Message Date
Chao Yu 6ad7609a18 f2fs: introduce __remove_dirty_inode
Introduce __remove_dirty_inode to clean up codes in remove_dirty_dir_inode.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-12-15 13:31:28 -08:00
Chao Yu 2710fd7e00 f2fs: introduce dirty list node in inode info
Add a new dirt list node member in inode info for linking the inode to
global dirty list in superblock, instead of old implementation which
allocate slab cache memory as an entry to inode.

It avoids memory pressure due to slab cache allocation, and also makes
codes more clean.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-12-15 13:24:19 -08:00
Chao Yu a49324f127 f2fs: rename {add,remove,release}_dirty_inode to {add,remove,release}_ino_entry
remove_dirty_dir_inode will be renamed to remove_dirty_inode as a generic
function in following patch for removing directory/regular/symlink inode
in global dirty list.

Here rename ino management related functions for readability, also in
order to avoid name conflict.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-12-15 13:23:43 -08:00
Chao Yu 9a59b62fd8 f2fs: do more integrity verification for superblock
Do more sanity check for superblock during ->mount.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-12-14 18:58:13 -08:00
Fan Li e8931582bd f2fs: fix to update variable correctly when skip a unmapped block
map.m_len should be reduced after skip a block

Signed-off-by: Fan li <fanofcode.li@samsung.com>
Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-12-14 10:17:54 -08:00
Fan Li d8fe4f0e74 f2fs: write only the pages in range during defragment
@lend of filemap_write_and_wait_range is supposed to be a "offset
in bytes where the range ends (inclusive)". Subtract 1 to avoid
writing an extra page.

Signed-off-by: Fan li <fanofcode.li@samsung.com>
Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-12-14 10:17:54 -08:00
Chao Yu e1c51b9f1d f2fs: clean up node page updating flow
If read_node_page return LOCKED_PAGE, in its caller it's better a) skip
unneeded 'Update' flag and mapping info verfication; b) check nid value
stored in footer structure of node page.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-12-14 09:09:17 -08:00
Jaegeuk Kim ea212a4a7a f2fs: use lock_buffer when changing superblock
When modifying sb contents, we need to use lock its buffer.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-12-09 09:53:18 -08:00
Jaegeuk Kim 5d909cdbbb f2fs: refactor f2fs_commit_super
Previously, f2fs_commit_super hacks the bh->blocknr to write the broken
alternate superblock.
Instead of it, we should use the correct logic to retrieve its buffer head
with locking it appropriately.

Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-12-09 09:51:07 -08:00
Jaegeuk Kim 80609448cd f2fs: enhance the bit operation for SSR
This patch enhances the existing bit operation when f2fs allocates SSR
blocks.

Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-12-09 09:50:32 -08:00
Chao Yu 0cab80ee0c f2fs: fix to convert inline inode in ->setattr
In commit 3c45414527 ("f2fs: do not trim preallocated blocks when
truncating after i_size"), in order to follow the regulation: "truncate(x)
where x > i_size will not trim all blocks past i_size." like other file
systems, in ->setattr we invoked truncate_setsize instead of f2fs_truncate
to avoid unneeded block trimming in such case, but forgot to call
f2fs_convert_inline_inode keep consistency of inline data conversion rule.

This patch fixes to convert inline data if necessary.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-12-04 13:14:44 -08:00
Chao Yu 3519e3f992 f2fs: use sbi->blocks_per_seg to avoid unnecessary calculation
Use sbi->blocks_per_seg directly to avoid unnecessary calculation when using
1 << sbi->log_blocks_per_seg.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-12-04 12:07:57 -08:00
Chao Yu 9006f2c93f f2fs: kill f2fs_drop_largest_extent
For direct IO, f2fs only allocate new address for the block which is not
exist in the disk before, its mapping info should not exist in extent
cache previously, so here we do not need to call f2fs_drop_largest_extent
to drop related cache.

Due to no more callers for f2fs_drop_largest_extent now, kill it.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-12-04 12:07:57 -08:00
Chao Yu b7973f2378 f2fs: clean up argument of recover_data
In recover_data, value of argument 'type' will be CURSEG_WARM_NODE all
the time, remove it for cleanup.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-12-04 12:07:56 -08:00
Chao Yu 855639deca f2fs: clean up code with __has_cursum_space
Clean up codes in lookup_journal_in_cursum() with __has_cursum_space().

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-12-04 12:07:55 -08:00
Chao Yu e9837bc2a4 f2fs: clean up error path in f2fs_readdir
No logic changes, just clean up the error path.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-12-04 12:07:55 -08:00
Jaegeuk Kim 807b1e1c8e f2fs: do not recover from previous remained wrong dnodes
If device does not support discard, some obsolete dnodes can be recovered
by roll-forward. This patch enhances the recovery flow.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-12-04 11:52:36 -08:00
Jaegeuk Kim 760de7914e f2fs: avoid deadlock in f2fs_shrink_extent_tree
While handling extent trees, we can enter into a reclaiming path anytime.
If it tries to release some extent nodes in the same extent tree,
write_lock(&et->lock) would be hanged.
In order to avoid the deadlock, we can just skip it.

Note that, if it is an unreferenced tree, we should get write_lock(&et->lock)
successfully and release all of therein nodes.

Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-12-04 11:52:36 -08:00
Chao Yu 57b62d29ad f2fs: fix to report error in f2fs_readdir
get_lock_data_page in f2fs_readdir can fail due to a lot of reasons (i.e.
no memory or IO error...), it's better to report this kind of error to
user rather than ignoring it.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-12-04 11:52:35 -08:00
Chao Yu f478f43fa0 f2fs: clear page uptodate when dropping cache for atomic write
We should clear uptodate flag for all pages atomic written when we drop
them, otherwise before these cached pages were reclaimed or invalidated
eventually, we will see invalid data when hitting them again.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-12-04 11:52:35 -08:00
Fan Li 692223d132 f2fs: optimize __find_rev_next_bit
1. Skip __reverse_ulong if the bitmap is empty.
2. Reduce branches and codes.
According to my test, the performance of this new version is 5% higher on
an empty bitmap of 64bytes, and remains about the same in the worst scenario.

Signed-off-by: Fan li <fanofcode.li@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-12-04 11:52:35 -08:00
Chao Yu eb7e813cc7 f2fs: fix to remove directory inode from dirty list
If last dirty dentry page was writebacked in reclaim path, we should
remove its directory inode from global dirty list to avoid unnecessary
flush for this inode when doing checkpoint.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-12-04 11:52:34 -08:00
Chao Yu 04ef4b626c f2fs: fix to enable missing ioctl interfaces in ->compat_ioctl
In 64-bit kernel f2fs can supports 32-bit ioctl system call by identifying
encoded code which is converted from 32-bit one to 64-bit one in
->compat_ioctl.

When we introduced new interfaces in ->ioctl, we forgot to enable them in
->compat_ioctl, so enable them for fixing.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
[Jaegeuk Kim: fix wrongly added spaces together]
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-12-04 11:52:34 -08:00
Chao Yu 29ba108d9b f2fs: fix memory leak of kobject in error path of fill_super
f2fs_sb_info::s_kobj should be released in error path of fill_super,
otherwise it will lead to memory leak.

This bug was found by kmemleak:

dmesg:
kmemleak: 2 new suspected memory leaks (see /sys/kernel/debug/kmemleak)

cat /sys/kernel/debug/kmemleak
unreferenced object 0xffff8800838dc358 (size 8):
  comm "mount", pid 4154, jiffies 4297482839 (age 1911.412s)
  hex dump (first 8 bytes):
    7a 72 61 6d 31 00 ff ff                          zram1...
  backtrace:
    [<ffffffff817a3668>] kmemleak_alloc+0x28/0x50
    [<ffffffff811dc99f>] __kmalloc_track_caller+0xef/0x1c0
    [<ffffffff8119d1c5>] kstrdup+0x45/0x80
    [<ffffffff8119d228>] kstrdup_const+0x28/0x30
    [<ffffffff813d2333>] kvasprintf_const+0x63/0xa0
    [<ffffffff813c59fc>] kobject_set_name_vargs+0x3c/0xa0
    [<ffffffff813c5a85>] kobject_add_varg+0x25/0x60
    [<ffffffff813c5b13>] kobject_init_and_add+0x53/0x70
    [<ffffffffa07ced19>] f2fs_fill_super+0x9d9/0xc40 [f2fs]
    [<ffffffff811ff0b2>] mount_bdev+0x192/0x1d0
    [<ffffffffa07cd3e5>] f2fs_mount+0x15/0x20 [f2fs]
    [<ffffffff811fec93>] mount_fs+0x43/0x170
    [<ffffffff81220256>] vfs_kern_mount+0x76/0x160
    [<ffffffff812211c8>] do_mount+0x258/0xdc0
    [<ffffffff81221dab>] SyS_mount+0x7b/0xc0
    [<ffffffff817aecd7>] entry_SYSCALL_64_fastpath+0x12/0x6f
...

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-12-04 11:52:34 -08:00
Chao Yu d323d005ac f2fs: support file defragment
This patch introduces a new ioctl F2FS_IOC_DEFRAGMENT to support file
defragment in a specified range of regular file.

This ioctl can be used in very limited workload: if user expects high
sequential read performance in randomly written file, this interface
can be used for defragmentation, after that file can be written as
continuous as possible in the device.

Meanwhile, it has side-effect, it will make holes in segments where
blocks located originally, so it's better to trigger GC to eliminate
fragment in segments.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-12-04 11:52:33 -08:00
Chao Yu 2da3e02746 f2fs: commit atomic written page in LFS mode
We should always commit atomic written pages in LFS mode, otherwise data
will become corrupted if we encounter suddent power cut after partial
pages committed in IPU mode.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-12-04 11:52:33 -08:00
Chao Yu 787c7b8cb3 f2fs: report error of f2fs_create_root_stats
f2fs_create_root_stats can fail due to no memory, report it to user.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-12-04 11:52:33 -08:00
Linus Torvalds 071f5d105a Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:
 "A lot of Thanksgiving turkey leftovers accumulated, here goes:

   1) Fix bluetooth l2cap_chan object leak, from Johan Hedberg.

   2) IDs for some new iwlwifi chips, from Oren Givon.

   3) Fix rtlwifi lockups on boot, from Larry Finger.

   4) Fix memory leak in fm10k, from Stephen Hemminger.

   5) We have a route leak in the ipv6 tunnel infrastructure, fix from
      Paolo Abeni.

   6) Fix buffer pointer handling in arm64 bpf JIT,f rom Zi Shen Lim.

   7) Wrong lockdep annotations in tcp md5 support, fix from Eric
      Dumazet.

   8) Work around some middle boxes which prevent proper handling of TCP
      Fast Open, from Yuchung Cheng.

   9) TCP repair can do huge kmalloc() requests, build paged SKBs
      instead.  From Eric Dumazet.

  10) Fix msg_controllen overflow in scm_detach_fds, from Daniel
      Borkmann.

  11) Fix device leaks on ipmr table destruction in ipv4 and ipv6, from
      Nikolay Aleksandrov.

  12) Fix use after free in epoll with AF_UNIX sockets, from Rainer
      Weikusat.

  13) Fix double free in VRF code, from Nikolay Aleksandrov.

  14) Fix skb leaks on socket receive queue in tipc, from Ying Xue.

  15) Fix ifup/ifdown crach in xgene driver, from Iyappan Subramanian.

  16) Fix clearing of persistent array maps in bpf, from Daniel
      Borkmann.

  17) In TCP, for the cross-SYN case, we don't initialize tp->copied_seq
      early enough.  From Eric Dumazet.

  18) Fix out of bounds accesses in bpf array implementation when
      updating elements, from Daniel Borkmann.

  19) Fill gaps in RCU protection of np->opt in ipv6 stack, from Eric
      Dumazet.

  20) When dumping proxy neigh entries, we have to accomodate NULL
      device pointers properly, from Konstantin Khlebnikov.

  21) SCTP doesn't release all ipv6 socket resources properly, fix from
      Eric Dumazet.

  22) Prevent underflows of sch->q.qlen for multiqueue packet
      schedulers, also from Eric Dumazet.

  23) Fix MAC and unicast list handling in bnxt_en driver, from Jeffrey
      Huang and Michael Chan.

  24) Don't actively scan radar channels, from Antonio Quartulli"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (110 commits)
  net: phy: reset only targeted phy
  bnxt_en: Setup uc_list mac filters after resetting the chip.
  bnxt_en: enforce proper storing of MAC address
  bnxt_en: Fixed incorrect implementation of ndo_set_mac_address
  net: lpc_eth: remove irq > NR_IRQS check from probe()
  net_sched: fix qdisc_tree_decrease_qlen() races
  openvswitch: fix hangup on vxlan/gre/geneve device deletion
  ipv4: igmp: Allow removing groups from a removed interface
  ipv6: sctp: implement sctp_v6_destroy_sock()
  arm64: bpf: add 'store immediate' instruction
  ipv6: kill sk_dst_lock
  ipv6: sctp: add rcu protection around np->opt
  net/neighbour: fix crash at dumping device-agnostic proxy entries
  sctp: use GFP_USER for user-controlled kmalloc
  sctp: convert sack_needed and sack_generation to bits
  ipv6: add complete rcu protection around np->opt
  bpf: fix allocation warnings in bpf maps and integer overflow
  mvebu: dts: enable IP checksum with jumbo frames for Armada 38x on Port0
  net: mvneta: enable setting custom TX IP checksum limit
  net: mvneta: fix error path for building skb
  ...
2015-12-03 16:02:46 -08:00
Linus Torvalds 2873d32ff4 Merge branch 'for-linus' of git://git.kernel.dk/linux-block
Pull block fixes from Jens Axboe:
 "A collection of fixes from this series.  The most important here is a
  regression fix for an issue that some folks would hit in blk-merge.c,
  and the NVMe queue depth limit for the screwed up Apple "nvme"
  controller.

  In more detail, this pull request contains:

   - a set of fixes for null_blk, including a fix for a few corner cases
     where we could hang the device.  From Arianna and Paolo.

   - lightnvm:
        - A build improvement from Keith.
        - Update the qemu pci id detection from Matias.
        - Error handling fixes for leaks and other little fixes from
          Sudip and Wenwei.

   - fix from Eric where BLKRRPART would not return EBUSY for whole
     device mounts, only when partitions were mounted.

   - fix from Jan Kara, where EOF O_DIRECT reads would return
     negatively.

   - remove check for rq_mergeable() when checking limits for cloned
     requests.  The check doesn't make any sense.  It's assuming that
     since NOMERGE is set on the request that we don't have to
     recalculate limits since the request didn't change, but that's not
     true if the request has been redirected.  From Hannes.

   - correctly get the bio front segment value set for single segment
     bio's, fixing a BUG() in blk-merge.  From Ming"

* 'for-linus' of git://git.kernel.dk/linux-block:
  nvme: temporary fix for Apple controller reset
  null_blk: change type of completion_nsec to unsigned long
  null_blk: guarantee device restart in all irq modes
  null_blk: set a separate timer for each command
  blk-merge: fix computing bio->bi_seg_front_size in case of single segment
  direct-io: Fix negative return from dio read beyond eof
  block: Always check queue limits for cloned requests
  lightnvm: missing nvm_lock acquire
  lightnvm: unconverted ppa returned in get_bb_tbl
  lightnvm: refactor and change vendor id for qemu
  lightnvm: do device max sectors boundary check first
  lightnvm: fix ioctl memory leaks
  lightnvm: free memory when gennvm register fails
  lightnvm: Simplify config when disabled
  Return EBUSY from BLKRRPART for mounted whole-dev fs
2015-12-03 15:45:16 -08:00
Eric Dumazet 9cd3e072b0 net: rename SOCK_ASYNC_NOSPACE and SOCK_ASYNC_WAITDATA
This patch is a cleanup to make following patch easier to
review.

Goal is to move SOCK_ASYNC_NOSPACE and SOCK_ASYNC_WAITDATA
from (struct socket)->flags to a (struct socket_wq)->flags
to benefit from RCU protection in sock_wake_async()

To ease backports, we rename both constants.

Two new helpers, sk_set_bit(int nr, struct sock *sk)
and sk_clear_bit(int net, struct sock *sk) are added so that
following patch can change their implementation.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-12-01 15:45:05 -05:00
Jan Kara 74cedf9b6c direct-io: Fix negative return from dio read beyond eof
Assume a filesystem with 4KB blocks. When a file has size 1000 bytes and
we issue direct IO read at offset 1024, blockdev_direct_IO() reads the
tail of the last block and the logic for handling short DIO reads in
dio_complete() results in a return value -24 (1000 - 1024) which
obviously confuses userspace.

Fix the problem by bailing out early once we sample i_size and can
reliably check that direct IO read starts beyond i_size.

Reported-by: Avi Kivity <avi@scylladb.com>
Fixes: 9fe55eea7e
CC: stable@vger.kernel.org
CC: Steven Whitehouse <swhiteho@redhat.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-11-30 10:15:42 -07:00
Linus Torvalds 8003a57356 NFS client bugfixes for Linux 4.4
Highlights include:
 
 Stable patches:
 - Fix a NFSv4 callback identifier leak that was also causing client crashes
 - Fix NFSv4 callback decoding issues when incoming requests are truncated
 - Don't declare the attribute cache valid when we call nfs_update_inode with
   an empty attribute structure.
 - Resend LAYOUTGET when there is a race that changes the seqid
 
 Bugfixes:
 - Fix a number of issues with the NFSv4.2 CLONE ioctl()
 - Properly set NFS v4.2 NFSDBG_FACILITY
 - NFSv4 referrals are broken; Cleanup FATTR4_WORD0_FS_LOCATIONS after
   decoding success
 - Use sliding delay when LAYOUTGET gets NFS4ERR_DELAY
 - Ensure that attrcache is revalidated after a SETATTR
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Merge tag 'nfs-for-4.4-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

Pull NFS client bugfixes from Trond Myklebust:
 "Highlights include:

  Stable patches:
   - Fix a NFSv4 callback identifier leak that was also causing client
     crashes
   - Fix NFSv4 callback decoding issues when incoming requests are
     truncated
   - Don't declare the attribute cache valid when we call
     nfs_update_inode with an empty attribute structure.
   - Resend LAYOUTGET when there is a race that changes the seqid

  Bugfixes:
   - Fix a number of issues with the NFSv4.2 CLONE ioctl()
   - Properly set NFS v4.2 NFSDBG_FACILITY
   - NFSv4 referrals are broken; Cleanup FATTR4_WORD0_FS_LOCATIONS after
     decoding success
   - Use sliding delay when LAYOUTGET gets NFS4ERR_DELAY
   - Ensure that attrcache is revalidated after a SETATTR"

* tag 'nfs-for-4.4-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
  nfs4: resend LAYOUTGET when there is a race that changes the seqid
  nfs: if we have no valid attrs, then don't declare the attribute cache valid
  nfs: ensure that attrcache is revalidated after a SETATTR
  nfs4: limit callback decoding to received bytes
  nfs4: start callback_ident at idr 1
  nfs: use sliding delay when LAYOUTGET gets NFS4ERR_DELAY
  NFS4: Cleanup FATTR4_WORD0_FS_LOCATIONS after decoding success
  NFS: Properly set NFS v4.2 NFSDBG_FACILITY
  nfs: reduce the amount of ifdefs for v4.2 in nfs4file.c
  nfs: use btrfs ioctl defintions for clone
  nfs: allow intra-file CLONE
  nfs: offer native ioctls even if CONFIG_COMPAT is set
  nfs: pass on count for CLONE operations
2015-11-27 17:22:47 -08:00
Linus Torvalds 80e0c505b2 Merge branch 'for-linus-4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs fixes from Chris Mason:
 "This has Mark Fasheh's patches to fix quota accounting during subvol
  deletion, which we've been working on for a while now.  The patch is
  pretty small but it's a key fix.

  Otherwise it's a random assortment"

* 'for-linus-4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  btrfs: fix balance range usage filters in 4.4-rc
  btrfs: qgroup: account shared subtree during snapshot delete
  Btrfs: use btrfs_get_fs_root in resolve_indirect_ref
  btrfs: qgroup: fix quota disable during rescan
  Btrfs: fix race between cleaner kthread and space cache writeout
  Btrfs: fix scrub preventing unused block groups from being deleted
  Btrfs: fix race between scrub and block group deletion
  btrfs: fix rcu warning during device replace
  btrfs: Continue replace when set_block_ro failed
  btrfs: fix clashing number of the enhanced balance usage filter
  Btrfs: fix the number of transaction units needed to remove a block group
  Btrfs: use global reserve when deleting unused block group after ENOSPC
  Btrfs: tests: checking for NULL instead of IS_ERR()
  btrfs: fix signed overflows in btrfs_sync_file
2015-11-27 15:45:45 -08:00
Jeff Layton 4f2e9dce0c nfs4: resend LAYOUTGET when there is a race that changes the seqid
pnfs_layout_process will check the returned layout stateid against what
the kernel has in-core. If it turns out that the stateid we received is
older, then we should resend the LAYOUTGET instead of falling back to
MDS I/O.

Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Cc: stable@vger.kernel.org # 3.18+
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-11-25 15:32:13 -05:00
Jeff Layton c812012f9c nfs: if we have no valid attrs, then don't declare the attribute cache valid
If we pass in an empty nfs_fattr struct to nfs_update_inode, it will
(correctly) not update any of the attributes, but it then clears the
NFS_INO_INVALID_ATTR flag, which indicates that the attributes are
up to date. Don't clear the flag if the fattr struct has no valid
attrs to apply.

Reviewed-by: Steve French <steve.french@primarydata.com>
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Cc: stable@vger.kernel.org
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-11-25 15:31:49 -05:00
Jeff Layton 616c319683 nfs: ensure that attrcache is revalidated after a SETATTR
If we get no post-op attributes back from a SETATTR operation, then no
attributes will of course be updated during the call to
nfs_update_inode.

We know however that the attributes are invalid at that point, since we
just changed some of them. At the very least, the ctime will be bogus.
If we get no post-op attributes back on the call, mark the attrcache
invalid to reflect that fact.

Reviewed-by: Steve French <steve.french@primarydata.com>
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-11-25 15:24:30 -05:00
Holger Hoffstätte dba72cb30b btrfs: fix balance range usage filters in 4.4-rc
There's a regression in 4.4-rc since commit bc3094673f
(btrfs: extend balance filter usage to take minimum and maximum) in that
existing (non-ranged) balance with -dusage=x no longer works; all chunks
are skipped.

After staring at the code for a while and wondering why a non-ranged
balance would even need min and max thresholds (..which then were not
set correctly, leading to the bug) I realized that the only problem
was the fact that the filter functions were named wrong, thanks to
patching copypasta. Simply renaming both functions lets the existing
btrfs-progs call balance with -dusage=x and now the non-ranged filter
function is invoked, properly using only a single chunk limit.

Signed-off-by: Holger Hoffstätte <holger.hoffstaette@googlemail.com>
Fixes: bc3094673f ("btrfs: extend balance filter usage to take minimum and maximum")
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-11-25 05:27:33 -08:00
Mark Fasheh 82bd101b52 btrfs: qgroup: account shared subtree during snapshot delete
Commit 0ed4792 ('btrfs: qgroup: Switch to new extent-oriented qgroup
mechanism.') removed our qgroup accounting during
btrfs_drop_snapshot(). Predictably, this results in qgroup numbers
going bad shortly after a snapshot is removed.

Fix this by adding a dirty extent record when we encounter extents during
our shared subtree walk. This effectively restores the functionality we had
with the original shared subtree walking code in 1152651 (btrfs: qgroup:
account shared subtrees during snapshot delete).

The idea with the original patch (and this one) is that shared subtrees can
get skipped during drop_snapshot. The shared subtree walk then allows us a
chance to visit those extents and add them to the qgroup work for later
processing. This ultimately makes the accounting for drop snapshot work.

The new qgroup code nicely handles all the other extents during the tree
walk via the ref dec/inc functions so we don't have to add actions beyond
what we had originally.

Signed-off-by: Mark Fasheh <mfasheh@suse.de>
Signed-off-by: Chris Mason <clm@fb.com>
2015-11-25 05:27:33 -08:00
Josef Bacik 2d9e977610 Btrfs: use btrfs_get_fs_root in resolve_indirect_ref
The backref code will look up the fs_root we're trying to resolve our indirect
refs for, unfortunately we use btrfs_read_fs_root_no_name, which returns -ENOENT
if the ref is 0.  This isn't helpful for the qgroup stuff with snapshot delete
as it won't be able to search down the snapshot we are deleting, which will
cause us to miss roots.  So use btrfs_get_fs_root and send false for check_ref
so we can always get the root we're looking for.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.de>
Signed-off-by: Chris Mason <clm@fb.com>
2015-11-25 05:22:08 -08:00
Justin Maggard 967ef5131e btrfs: qgroup: fix quota disable during rescan
There's a race condition that leads to a NULL pointer dereference if you
disable quotas while a quota rescan is running.  To fix this, we just need
to wait for the quota rescan worker to actually exit before tearing down
the quota structures.

Signed-off-by: Justin Maggard <jmaggard@netgear.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-11-25 05:22:08 -08:00
Filipe Manana 036a9348dc Btrfs: fix race between cleaner kthread and space cache writeout
When a block group becomes unused and the cleaner kthread is currently
running, we can end up getting the current transaction aborted with error
-ENOENT when we try to commit the transaction, leading to the following
trace:

  [59779.258768] WARNING: CPU: 3 PID: 5990 at fs/btrfs/extent-tree.c:3740 btrfs_write_dirty_block_groups+0x17c/0x214 [btrfs]()
  [59779.272594] BTRFS: Transaction aborted (error -2)
  (...)
  [59779.291137] Call Trace:
  [59779.291621]  [<ffffffff812566f4>] dump_stack+0x4e/0x79
  [59779.292543]  [<ffffffff8104d0a6>] warn_slowpath_common+0x9f/0xb8
  [59779.293435]  [<ffffffffa04cb81f>] ? btrfs_write_dirty_block_groups+0x17c/0x214 [btrfs]
  [59779.295000]  [<ffffffff8104d107>] warn_slowpath_fmt+0x48/0x50
  [59779.296138]  [<ffffffffa04c2721>] ? write_one_cache_group.isra.32+0x77/0x82 [btrfs]
  [59779.297663]  [<ffffffffa04cb81f>] btrfs_write_dirty_block_groups+0x17c/0x214 [btrfs]
  [59779.299141]  [<ffffffffa0549b0d>] commit_cowonly_roots+0x1de/0x261 [btrfs]
  [59779.300359]  [<ffffffffa04dd5b6>] btrfs_commit_transaction+0x4c4/0x99c [btrfs]
  [59779.301805]  [<ffffffffa04b5df4>] btrfs_sync_fs+0x145/0x1ad [btrfs]
  [59779.302893]  [<ffffffff81196634>] sync_filesystem+0x7f/0x93
  (...)
  [59779.318186] ---[ end trace 577e2daff90da33a ]---

The following diagram illustrates a sequence of steps leading to this
problem:

       CPU 1                                             CPU 2

                           <at transaction N>

                                                        adds bg A to list
                                                        fs_info->unused_bgs

                                                        adds bg B to list
                                                        fs_info->unused_bgs

                           <transaction kthread
                            commits transaction N
                            and wakes up the
                            cleaner kthread>

  cleaner kthread
    delete_unused_bgs()

      sees bg A in list
      fs_info->unused_bgs

      btrfs_start_transaction()

                           <transaction N + 1 starts>

      deletes bg A

                                                        update_block_group(bg C)

                                                          --> adds bg C to list
                                                              fs_info->unused_bgs

      deletes bg B

      sees bg C in the list
      fs_info->unused_bgs

      btrfs_remove_chunk(bg C)
        btrfs_remove_block_group(bg C)

          --> checks if the block group
              is in a dirty list, and
              because it isn't now, it
              does nothing

          --> the block group item
              is deleted from the
              extent tree

                                                          --> adds bg C to list
                                                              transaction->dirty_bgs

                                                         some task calls
                                                         btrfs_commit_transaction(t N + 1)
                                                           commit_cowonly_roots()
                                                             btrfs_write_dirty_block_groups()
                                                               --> sees bg C in cur_trans->dirty_bgs
                                                               --> calls write_one_cache_group()
                                                                   which returns -ENOENT because
                                                                   it did not find the block group
                                                                   item in the extent tree
                                                               --> transaction aborte with -ENOENT
                                                                   because write_one_cache_group()
                                                                   returned that error

So fix this by adding a block group to the list of dirty block groups
before adding it to the list of unused block groups.

This happened on a stress test using fsstress plus concurrent calls to
fallocate 20G and truncate (releasing part of the space allocated with
fallocate).

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-11-25 05:22:08 -08:00
Filipe Manana 758f2dfcf8 Btrfs: fix scrub preventing unused block groups from being deleted
Currently scrub can race with the cleaner kthread when the later attempts
to delete an unused block group, and the result is preventing the cleaner
kthread from ever deleting later the block group - unless the block group
becomes used and unused again. The following diagram illustrates that
race:

              CPU 1                                 CPU 2

 cleaner kthread
   btrfs_delete_unused_bgs()

     gets block group X from
     fs_info->unused_bgs and
     removes it from that list

                                             scrub_enumerate_chunks()

                                               searches device tree using
                                               its commit root

                                               finds device extent for
                                               block group X

                                               gets block group X from the tree
                                               fs_info->block_group_cache_tree
                                               (via btrfs_lookup_block_group())

                                               sets bg X to RO

     sees the block group is
     already RO and therefore
     doesn't delete it nor adds
     it back to unused list

So fix this by making scrub add the block group again to the list of
unused block groups if the block group is still unused when it finished
scrubbing it and it hasn't been removed already.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-11-25 05:22:08 -08:00
Filipe Manana 020d5b7366 Btrfs: fix race between scrub and block group deletion
Scrub can race with the cleaner kthread deleting block groups that are
unused (and with relocation too) leading to a failure with error -EINVAL
that gets returned to user space.

The following diagram illustrates how it happens:

              CPU 1                                 CPU 2

 cleaner kthread
   btrfs_delete_unused_bgs()

     gets block group X from
     fs_info->unused_bgs

     sets block group to RO

       btrfs_remove_chunk(bg X)

         deletes device extents

                                         scrub_enumerate_chunks()

                                           searches device tree using
                                           its commit root

                                           finds device extent for
                                           block group X

                                           gets block group X from the tree
                                           fs_info->block_group_cache_tree
                                           (via btrfs_lookup_block_group())

                                           sets bg X to RO (again)

          btrfs_remove_block_group(bg X)

            deletes block group from
            fs_info->block_group_cache_tree

            removes extent map from
            fs_info->mapping_tree

                                               scrub_chunk(offset X)

                                                 searches fs_info->mapping_tree
                                                 for extent map starting at
                                                 offset X

                                                    --> doesn't find any such
                                                        extent map
                                                    --> returns -EINVAL and scrub
                                                        errors out to userspace
                                                        with -EINVAL

Fix this by dealing with an extent map lookup failure as an indicator of
block group deletion.
Issue reproduced with fstest btrfs/071.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-11-25 05:19:51 -08:00
David Sterba 31388ab2ed btrfs: fix rcu warning during device replace
The test btrfs/011 triggers a rcu warning
Reviewed-by: Anand Jain <anand.jain@oracle.com>

===============================
[ INFO: suspicious RCU usage. ]
4.4.0-rc1-default+ #286 Tainted: G        W
-------------------------------
fs/btrfs/volumes.c:1977 suspicious rcu_dereference_check() usage!

other info that might help us debug this:

rcu_scheduler_active = 1, debug_locks = 0
4 locks held by btrfs/28786:

0:  (&fs_info->dev_replace.lock_finishing_cancel_unmount){+.+...}, at: [<ffffffffa00bc785>] btrfs_dev_replace_finishing+0x45/0xa00 [btrfs]
1:  (uuid_mutex){+.+.+.}, at: [<ffffffffa00bc84f>] btrfs_dev_replace_finishing+0x10f/0xa00 [btrfs]
2:  (&fs_devs->device_list_mutex){+.+.+.}, at: [<ffffffffa00bc868>] btrfs_dev_replace_finishing+0x128/0xa00 [btrfs]
3:  (&fs_info->chunk_mutex){+.+...}, at: [<ffffffffa00bc87d>] btrfs_dev_replace_finishing+0x13d/0xa00 [btrfs]

stack backtrace:
CPU: 0 PID: 28786 Comm: btrfs Tainted: G        W       4.4.0-rc1-default+ #286
Hardware name: Intel Corporation SandyBridge Platform/To be filled by O.E.M., BIOS ASNBCPT1.86C.0031.B00.1006301607 06/30/2010
0000000000000001 ffff8800a07dfb48 ffffffff8141d47b 0000000000000001
0000000000000001 0000000000000000 ffff8801464a4f00 ffff8800a07dfb78
ffffffff810cd883 ffff880146eb9400 ffff8800a3698600 ffff8800a33fe220
Call Trace:
[<ffffffff8141d47b>] dump_stack+0x4f/0x74
[<ffffffff810cd883>] lockdep_rcu_suspicious+0x103/0x140
[<ffffffffa0071261>] btrfs_rm_dev_replace_remove_srcdev+0x111/0x130 [btrfs]
[<ffffffff810d354d>] ? trace_hardirqs_on+0xd/0x10
[<ffffffff81449536>] ? __percpu_counter_sum+0x66/0x80
[<ffffffffa00bcc15>] btrfs_dev_replace_finishing+0x4d5/0xa00 [btrfs]
[<ffffffffa00bc96e>] ? btrfs_dev_replace_finishing+0x22e/0xa00 [btrfs]
[<ffffffffa00a8795>] ? btrfs_scrub_dev+0x415/0x6d0 [btrfs]
[<ffffffffa003ea69>] ? btrfs_start_transaction+0x9/0x20 [btrfs]
[<ffffffffa00bda79>] btrfs_dev_replace_start+0x339/0x590 [btrfs]
[<ffffffff81196aa5>] ? __might_fault+0x95/0xa0
[<ffffffffa0078638>] btrfs_ioctl_dev_replace+0x118/0x160 [btrfs]
[<ffffffff811409c6>] ? stack_trace_call+0x46/0x70
[<ffffffffa007c914>] ? btrfs_ioctl+0x24/0x1770 [btrfs]
[<ffffffffa007ce43>] btrfs_ioctl+0x553/0x1770 [btrfs]
[<ffffffff811409c6>] ? stack_trace_call+0x46/0x70
[<ffffffff811d6eb1>] ? do_vfs_ioctl+0x21/0x5a0
[<ffffffff811d6f1c>] do_vfs_ioctl+0x8c/0x5a0
[<ffffffff811e3336>] ? __fget_light+0x86/0xb0
[<ffffffff811e3369>] ? __fdget+0x9/0x20
[<ffffffff811d7451>] ? SyS_ioctl+0x21/0x80
[<ffffffff811d7483>] SyS_ioctl+0x53/0x80
[<ffffffff81b1efd7>] entry_SYSCALL_64_fastpath+0x12/0x6f

This is because of unprotected use of rcu_dereference in
btrfs_scratch_superblocks. We can't add rcu locks around the whole
function because we read the superblock.

The fix will use the rcu string buffer directly without the rcu locking.
Thi is safe as the device will not go away in the meantime. We're
holding the device list mutexes.

Restructuring the code to narrow down the rcu section turned out to be
impossible, we need to call filp_open (through update_dev_time) on the
buffer and this could call kmalloc/__might_sleep. We could call kstrdup
with GFP_ATOMIC but it's not absolutely necessary.

Fixes: 12b1c2637b (Btrfs: enhance btrfs_scratch_superblock to scratch all superblocks)
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-11-25 05:19:51 -08:00
Zhaolei 76a8efa171 btrfs: Continue replace when set_block_ro failed
xfstests/011 failed in node with small_size filesystem.
Can be reproduced by following script:
  DEV_LIST="/dev/vdd /dev/vde"
  DEV_REPLACE="/dev/vdf"

  do_test()
  {
      local mkfs_opt="$1"
      local size="$2"

      dmesg -c >/dev/null
      umount $SCRATCH_MNT &>/dev/null

      echo  mkfs.btrfs -f $mkfs_opt "${DEV_LIST[*]}"
      mkfs.btrfs -f $mkfs_opt "${DEV_LIST[@]}" || return 1
      mount "${DEV_LIST[0]}" $SCRATCH_MNT

      echo -n "Writing big files"
      dd if=/dev/urandom of=$SCRATCH_MNT/t0 bs=1M count=1 >/dev/null 2>&1
      for ((i = 1; i <= size; i++)); do
          echo -n .
          /bin/cp $SCRATCH_MNT/t0 $SCRATCH_MNT/t$i || return 1
      done
      echo

      echo Start replace
      btrfs replace start -Bf "${DEV_LIST[0]}" "$DEV_REPLACE" $SCRATCH_MNT || {
          dmesg
          return 1
      }
      return 0
  }

  # Set size to value near fs size
  # for example, 1897 can trigger this bug in 2.6G device.
  #
  ./do_test "-d raid1 -m raid1" 1897

System will report replace fail with following warning in dmesg:
 [  134.710853] BTRFS: dev_replace from /dev/vdd (devid 1) to /dev/vdf started
 [  135.542390] BTRFS: btrfs_scrub_dev(/dev/vdd, 1, /dev/vdf) failed -28
 [  135.543505] ------------[ cut here ]------------
 [  135.544127] WARNING: CPU: 0 PID: 4080 at fs/btrfs/dev-replace.c:428 btrfs_dev_replace_start+0x398/0x440()
 [  135.545276] Modules linked in:
 [  135.545681] CPU: 0 PID: 4080 Comm: btrfs Not tainted 4.3.0 #256
 [  135.546439] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.8.2-0-g33fbe13 by qemu-project.org 04/01/2014
 [  135.547798]  ffffffff81c5bfcf ffff88003cbb3d28 ffffffff817fe7b5 0000000000000000
 [  135.548774]  ffff88003cbb3d60 ffffffff810a88f1 ffff88002b030000 00000000ffffffe4
 [  135.549774]  ffff88003c080000 ffff88003c082588 ffff88003c28ab60 ffff88003cbb3d70
 [  135.550758] Call Trace:
 [  135.551086]  [<ffffffff817fe7b5>] dump_stack+0x44/0x55
 [  135.551737]  [<ffffffff810a88f1>] warn_slowpath_common+0x81/0xc0
 [  135.552487]  [<ffffffff810a89e5>] warn_slowpath_null+0x15/0x20
 [  135.553211]  [<ffffffff81448c88>] btrfs_dev_replace_start+0x398/0x440
 [  135.554051]  [<ffffffff81412c3e>] btrfs_ioctl+0x1d2e/0x25c0
 [  135.554722]  [<ffffffff8114c7ba>] ? __audit_syscall_entry+0xaa/0xf0
 [  135.555506]  [<ffffffff8111ab36>] ? current_kernel_time64+0x56/0xa0
 [  135.556304]  [<ffffffff81201e3d>] do_vfs_ioctl+0x30d/0x580
 [  135.557009]  [<ffffffff8114c7ba>] ? __audit_syscall_entry+0xaa/0xf0
 [  135.557855]  [<ffffffff810011d1>] ? do_audit_syscall_entry+0x61/0x70
 [  135.558669]  [<ffffffff8120d1c1>] ? __fget_light+0x61/0x90
 [  135.559374]  [<ffffffff81202124>] SyS_ioctl+0x74/0x80
 [  135.559987]  [<ffffffff81809857>] entry_SYSCALL_64_fastpath+0x12/0x6f
 [  135.560842] ---[ end trace 2a5c1fc3205abbdd ]---

Reason:
 When big data writen to fs, the whole free space will be allocated
 for data chunk.
 And operation as scrub need to set_block_ro(), and when there is
 only one metadata chunk in system(or other metadata chunks
 are all full), the function will try to allocate a new chunk,
 and failed because no space in device.

Fix:
 When set_block_ro failed for metadata chunk, it is not a problem
 because scrub_lock paused commit_trancaction in same time, and
 metadata are always cowed, so the on-the-fly writepages will not
 write data into same place with scrub/replace.
 Let replace continue in this case is no problem.

Tested by above script, and xfstests/011, plus 100 times xfstests/070.

Changelog v1->v2:
1: Add detail comments in source and commit-message.
2: Add dmesg detail into commit-message.
3: Limit return value of -ENOSPC to be passed.
All suggested by: Filipe Manana <fdmanana@gmail.com>

Suggested-by: Filipe Manana <fdmanana@gmail.com>
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-11-25 05:19:51 -08:00
David Sterba da02c68989 btrfs: fix clashing number of the enhanced balance usage filter
I've accidentally picked an already used number for the enhanced usage
filter represented by BTRFS_BALANCE_ARGS_USAGE_RANGE, clashing with
BTRFS_BALANCE_ARGS_CONVERT. Introduced during the development phase,
no backward compatibility issues.

Reported-by: Holger Hoffstätte <holger.hoffstaette@googlemail.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Fixes: bc3094673f ("btrfs: extend balance filter usage to take minimum and maximum")
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-11-25 05:19:50 -08:00
Filipe Manana 7fd01182d1 Btrfs: fix the number of transaction units needed to remove a block group
We were using only 1 transaction unit when attempting to delete an unused
block group but in reality we need 3 + N units, where N corresponds to the
number of stripes. We were accounting only for the addition of the orphan
item (for the block group's free space cache inode) but we were not
accounting that we need to delete one block group item from the extent
tree, one free space item from the tree of tree roots and N device extent
items from the device tree.

While one unit is not enough, it worked most of the time because for each
single unit we are too pessimistic and assume an entire tree path, with
the highest possible heigth (8), needs to be COWed with eventual node
splits at every possible level in the tree, so there was usually enough
reserved space for removing all the items and adding the orphan item.

However after adding the orphan item, writepages() can by called by the VM
subsystem against the btree inode when we are under memory pressure, which
causes writeback to start for the nodes we COWed before, this forces the
operation to remove the free space item to COW again some (or all of) the
same nodes (in the tree of tree roots). Even without writepages() being
called, we could fail with ENOSPC because these items are located in
multiple trees and one of them might have a higher heigth and require
node/leaf splits at many levels, exhausting all the reserved space before
removing all the items and adding the orphan.

In the kernel 4.0 release, commit 3d84be7991 ("Btrfs: fix BUG_ON in
btrfs_orphan_add() when delete unused block group"), we attempted to fix
a BUG_ON due to ENOSPC when trying to add the orphan item by making the
cleaner kthread reserve one transaction unit before attempting to remove
the block group, but this was not enough. We had a couple user reports
still hitting the same BUG_ON after 4.0, like Stefan Priebe's report on
a 4.2-rc6 kernel for example:

    http://www.spinics.net/lists/linux-btrfs/msg46070.html

So fix this by reserving all the necessary units of metadata.

Reported-by: Stefan Priebe <s.priebe@profihost.ag>
Fixes: 3d84be7991 ("Btrfs: fix BUG_ON in btrfs_orphan_add() when delete unused block group")
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-11-25 05:19:50 -08:00
Filipe Manana 8eab77ff16 Btrfs: use global reserve when deleting unused block group after ENOSPC
It's possible to reach a state where the cleaner kthread isn't able to
start a transaction to delete an unused block group due to lack of enough
free metadata space and due to lack of unallocated device space to allocate
a new metadata block group as well. If this happens try to use space from
the global block group reserve just like we do for unlink operations, so
that we don't reach a permanent state where starting a transaction for
filesystem operations (file creation, renames, etc) keeps failing with
-ENOSPC. Such an unfortunate state was observed on a machine where over
a dozen unused data block groups existed and the cleaner kthread was
failing to delete them due to ENOSPC error when attempting to start a
transaction, and even running balance with a -dusage=0 filter failed with
ENOSPC as well. Also unmounting and mounting again the filesystem didn't
help. Allowing the cleaner kthread to use the global block reserve to
delete the unused data block groups fixed the problem.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-11-25 05:19:50 -08:00
Dan Carpenter 89b6c8d1e4 Btrfs: tests: checking for NULL instead of IS_ERR()
btrfs_alloc_dummy_root() return an error pointer on failure, it never
returns NULL.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-11-25 05:19:50 -08:00
David Sterba 9dcbeed4d7 btrfs: fix signed overflows in btrfs_sync_file
The calculation of range length in btrfs_sync_file leads to signed
overflow. This was caught by PaX gcc SIZE_OVERFLOW plugin.

https://forums.grsecurity.net/viewtopic.php?f=1&t=4284

The fsync call passes 0 and LLONG_MAX, the range length does not fit to
loff_t and overflows, but the value is converted to u64 so it silently
works as expected.

The minimal fix is a typecast to u64, switching functions to take
(start, end) instead of (start, len) would be more intrusive.

Coccinelle script found that there's one more opencoded calculation of
the length.

<smpl>
@@
loff_t start, end;
@@
* end - start
</smpl>

CC: stable@vger.kernel.org
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-11-25 05:19:50 -08:00