btrfs_bio is a bio abstraction able to split and not complete after the last
bio has returned (like the old btrfs_multi_bio). Additionally, btrfs_bio
tracks the mirror_num used to read data which can be used for error
correction purposes.
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>

these ioctls make use of the new functions initially added for scrub. they
return all inodes belonging to a logical address (BTRFS_IOC_LOGICAL_INO) and
all paths belonging to an inode (BTRFS_IOC_INO_PATHS).
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>

This removes a FIXME comment and introduces the first part of nodatasum
fixup: It gets the corresponding inode for a logical address and triggers a
regular readpage for the corrupted sector.

Once we have on-the-fly error correction our error will be automatically
corrected. The correction code is expected to clear the newly introduced
EXTENT_DAMAGED flag, making scrub report that error as "corrected" instead
of "uncorrectable" eventually.
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>

the rest of the code uses int mirror_num, and so should scrub
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>

Currently, extent_read_full_page always assumes we are trying to read mirror
0, which generally is the best we can do. To add flexibility, pass it as a
parameter. This will be needed by scrub fixup code.
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>

Fix the mirror_num determination in scrub_stripe. The rest of the scrub code
did not use mirror_num for anything important and that error went unnoticed.
The nodatasum fixup patch of this set depends on a correct mirror_num.
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>

While scrubbing, we may encounter various errors. Previously, a logical
address was printed to the log only. Now, all paths belonging to that
address are resolved and printed separately. That should work for hardlinks
as well as reflinks.
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>

In normal operation, scrub is reading data sequentially in large portions.
In case of an i/o error, we try to find the corrupted area(s) by issuing
page sized read requests. With this commit we increment the
unverified_errors counter if all of the small size requests succeed.

Userland patches carrying such conspicous events to the administrator should
already be around.
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>

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>

Fix a crash/BUG_ON in the clone ioctl due to insufficient reservation. We
need to reserve space for:

 - adjusting the old extent (possibly splitting it)
 - adding the new extent
 - updating the inode
Signed-off-by: Sage Weil <sage@newdream.net>
Signed-off-by: Chris Mason <chris.mason@oracle.com>

We can race with readdir and the RCU path walking stuff.  This is because we
clear the need lookup flag before actually instantiating the inode.  This will
lead the RCU path walk stuff to find a dentry it thinks is valid without a
d_inode attached.  So instead unhash the dentry when we first start the lookup,
and then clear the flag after we've instantiated the dentry so we're garunteed
to either try the slow lookup, or have the d_inode set properly.
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>

The recent reworking of btrfs' lseek lead to incorrect
values being returned.  This adds checks for seeking
beyond EOF in SEEK_HOLE and makes sure the error
values come back correct.

Andi Kleen also sent in similar patches.
Signed-off-by: Jie Liu <jeff.liu@oracle.com>
Reported-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>

The dst file will have the same inode flags with dst file after
file clone, and I think it's unexpected.

For example, the dst file will suddenly become immutable after
getting some share of data with src file, if the src is immutable.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>

To reproduce the bug:

  # mount /dev/sda7 /mnt
  # dd if=/dev/zero of=/mnt/src bs=4K count=1
  # umount /mnt

  # mount -o nodatasum /dev/sda7 /mnt
  # dd if=/dev/zero of=/mnt/dst bs=4K count=1
  # clone_range -s 4K -l 4K /mnt/src /mnt/dst

  # echo 3 > /proc/sys/vm/drop_caches
  # cat /mnt/dst
  # dmesg
  ...
  btrfs no csum found for inode 258 start 0
  btrfs csum failed ino 258 off 0 csum 2566472073 private 0

It's because part of the file is checksummed and the other part is not,
and then btrfs will complain checksum is not found when we read the file.

Disallow file clone if src and dst file have different checksum flag,
so we ensure a file is completely checksummed or unchecksummed.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>

It's a bug in commit f81c9cdc
(Btrfs: truncate pages from clone ioctl target range)

We should pass the dest range to the truncate function, but not the
src range.

Also move the function before locking extent state.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>

Since the d_off in the first dirent for "." (that originates from
the 4th argument "offset" of filldir() for the 2nd dirent for "..")
is wrongly assigned in btrfs_real_readdir(), telldir returns same
offset for different locations.

 | # mkfs.btrfs /dev/sdb1
 | # mount /dev/sdb1 fs0
 | # cd fs0
 | # touch file0 file1
 | # ../test
 | telldir: 0
 | readdir: d_off = 2, d_name = "."
 | telldir: 2
 | readdir: d_off = 2, d_name = ".."
 | telldir: 2
 | readdir: d_off = 3, d_name = "file0"
 | telldir: 3
 | readdir: d_off = 2147483647, d_name = "file1"
 | telldir: 2147483647

To fix this problem, pass filp->f_pos (which is loff_t) instead.

 | # ../test
 | telldir: 0
 | readdir: d_off = 1, d_name = "."
 | telldir: 1
 | readdir: d_off = 2, d_name = ".."
 | telldir: 2
 | readdir: d_off = 3, d_name = "file0"
 :

At the moment the "offset" for "." is unused because there is no
preceding dirent, however it is better to pass filp->f_pos to follow
grammatical usage.
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>

* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
  drm: Remove duplicate "return" statement
  drm/nv04/crtc: Bail out if FB is not bound to crtc
  drm/nouveau: fix nv04_sgdma_bind on non-"4kB pages" archs
  drm/nouveau: properly handle allocation failure in nouveau_sgdma_populate
  drm/nouveau: fix oops on pre-semaphore hardware
  drm/nv50/crtc: Bail out if FB is not bound to crtc
  drm/radeon/kms: fix DP detect and EDID fetch for DP bridges

* 'fixes' of git://git.linaro.org/people/arnd/arm-soc:
  ARM: CSR: add missing sentinels to of_device_id tables
  ARM: cns3xxx: Fix newly introduced warnings in the PCIe code
  ARM: cns3xxx: Fix compile error caused by hardware.h removed
  ARM: davinci: fix cache flush build error
  ARM: davinci: correct MDSTAT_STATE_MASK
  ARM: davinci: da850 EVM: read mac address from SPI flash
  OMAP: omap_device: fix !CONFIG_SUSPEND case in _noirq handlers
  OMAP2430: hwmod: musb: add missing terminator to omap2430_usbhsotg_addrs[]
  OMAP3: clock: indicate that gpt12_fck and wdt1_fck are in the WKUP clockdomain
  OMAP4: clock: fix compile warning
  OMAP4: clock: re-enable previous clockdomain enable/disable sequence
  OMAP: clockdomain: Wait for powerdomain to be ON when using clockdomain force wakeup
  OMAP: powerdomains: Make all powerdomain target states as ON at init

The LTTng 2.0 kernel tracer (stand-alone module package, available at
http://lttng.org) uses the 0xF6 ioctl range for tracer control and
transport operations.
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

* 'for-linus' of git://github.com/chrismason/linux:
  Btrfs: add dummy extent if dst offset excceeds file end in
  Btrfs: calc file extent num_bytes correctly in file clone
  btrfs: xattr: fix attribute removal
  Btrfs: fix wrong nbytes information of the inode
  Btrfs: fix the file extent gap when doing direct IO
  Btrfs: fix unclosed transaction handle in btrfs_cont_expand
  Btrfs: fix misuse of trans block rsv
  Btrfs: reset to appropriate block rsv after orphan operations
  Btrfs: skip locking if searching the commit root in csum lookup
  btrfs: fix warning in iput for bad-inode
  Btrfs: fix an oops when deleting snapshots

kmemleak is reporting that 32 bytes are being leaked by FUSE:

  unreferenced object 0xe373b270 (size 32):
  comm "fusermount", pid 1207, jiffies 4294707026 (age 2675.187s)
  hex dump (first 32 bytes):
    01 00 00 00 00 00 00 00 01 00 00 00 00 00 00 00  ................
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<b05517d7>] kmemleak_alloc+0x27/0x50
    [<b0196435>] kmem_cache_alloc+0xc5/0x180
    [<b02455be>] fuse_alloc_forget+0x1e/0x20
    [<b0245670>] fuse_alloc_inode+0xb0/0xd0
    [<b01b1a8c>] alloc_inode+0x1c/0x80
    [<b01b290f>] iget5_locked+0x8f/0x1a0
    [<b0246022>] fuse_iget+0x72/0x1a0
    [<b02461da>] fuse_get_root_inode+0x8a/0x90
    [<b02465cf>] fuse_fill_super+0x3ef/0x590
    [<b019e56f>] mount_nodev+0x3f/0x90
    [<b0244e95>] fuse_mount+0x15/0x20
    [<b019d1bc>] mount_fs+0x1c/0xc0
    [<b01b5811>] vfs_kern_mount+0x41/0x90
    [<b01b5af9>] do_kern_mount+0x39/0xd0
    [<b01b7585>] do_mount+0x2e5/0x660
    [<b01b7966>] sys_mount+0x66/0xa0

This leak report is consistent and happens once per boot on
3.1.0-rc5-dirty.

This happens if a FORGET request is queued after the fuse device was
released.
Reported-by: Sitsofe Wheeler <sitsofe@yahoo.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Tested-by: Sitsofe Wheeler <sitsofe@yahoo.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Commit 37fb3a30 ("fuse: fix flock") added in 3.1-rc4 caused flock() to
fail with ENOSYS with the kernel ABI version 7.16 or earlier.

Fix by falling back to testing FUSE_POSIX_LOCKS for ABI versions 7.16
and earlier.
Reported-by: Martin Ziegler <ziegler@email.mathematik.uni-freiburg.de>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Tested-by: Martin Ziegler <ziegler@email.mathematik.uni-freiburg.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

* 'v4l_for_linus' of git://linuxtv.org/mchehab/for_linus:
  [media] vp7045: fix buffer setup
  [media] nuvoton-cir: simplify raw IR sample handling
  [media] [Resend] viacam: Don't explode if pci_find_bus() returns NULL
  [media] v4l2: Fix documentation of the codec device controls
  [media] gspca - sonixj: Fix the darkness of sensor om6802 in 320x240
  [media] gspca - sonixj: Fix wrong register mask for sensor om6802
  [media] gspca - ov519: Fix LED inversion of some ov519 webcams
  [media] pwc: precedence bug in pwc_init_controls()

* 'for-linus' of git://openrisc.net/~jonas/linux:
  Add missing DMA ops
  openrisc: don't use pt_regs in struct sigcontext

You can see there's no file extent with range [0, 4096]. Check this by
btrfsck:

 # btrfsck /dev/sda7
 root 5 inode 258 errors 100
 ...
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>

num_bytes should be 4096 not 12288.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>

An attribute is not removed by 'setfattr -x attr file' and remains
visible in attr list. This makes xfstests/062 pass again.
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <chris.mason@oracle.com>

If we write some data into the data hole of the file(no preallocation for this
hole), Btrfs will allocate some disk space, and update nbytes of the inode, but
the other element--disk_i_size needn't be updated. At this condition, we must
update inode metadata though disk_i_size is not changed(btrfs_ordered_update_i_size()
return 1).

 # mkfs.btrfs /dev/sdb1
 # mount /dev/sdb1 /mnt
 # touch /mnt/a
 # truncate -s 856002 /mnt/a
 # dd if=/dev/zero of=/mnt/a bs=4K count=1 conv=nocreat,notrunc
 # umount /mnt
 # btrfsck /dev/sdb1
 root 5 inode 257 errors 400
 found 32768 bytes used err is 1
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>

When we write some data to the place that is beyond the end of the file
in direct I/O mode, a data hole will be created. And Btrfs should insert
a file extent item that point to this hole into the fs tree. But unfortunately
Btrfs forgets doing it.

The following is a simple way to reproduce it:
 # mkfs.btrfs /dev/sdc2
 # mount /dev/sdc2 /test4
 # touch /test4/a
 # dd if=/dev/zero of=/test4/a seek=8 count=1 bs=4K oflag=direct conv=nocreat,notrunc
 # umount /test4
 # btrfsck /dev/sdc2
 root 5 inode 257 errors 100
Reported-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Tested-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>

The function - btrfs_cont_expand() forgot to close the transaction handle before
it jump out the while loop. Fix it.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>

At the beginning of create_pending_snapshot, trans->block_rsv is set
to pending->block_rsv and is used for snapshot things, however, when
it is done, we do not recover it as will.
Signed-off-by: Liu Bo <liubo2009@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>

While truncating free space cache, we forget to change trans->block_rsv
back to the original one, but leave it with the orphan_block_rsv, and
then with option inode_cache enable, it leads to countless warnings of
btrfs_alloc_free_block and btrfs_orphan_commit_root:

WARNING: at fs/btrfs/extent-tree.c:5711 btrfs_alloc_free_block+0x180/0x350 [btrfs]()
...
WARNING: at fs/btrfs/inode.c:2193 btrfs_orphan_commit_root+0xb0/0xc0 [btrfs]()
Signed-off-by: Liu Bo <liubo2009@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>

It's not enough to just search the commit root, since we could be cow'ing the
very block we need to search through, which would mean that its locked and we'll
still deadlock.  So use path->skip_locking as well.  Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>

iput() shouldn't be called for inodes in I_NEW state.
We need to mark inode as constructed first.

WARNING: at fs/inode.c:1309 iput+0x20b/0x210()
Call Trace:
 [<ffffffff8103e7ba>] warn_slowpath_common+0x7a/0xb0
 [<ffffffff8103e805>] warn_slowpath_null+0x15/0x20
 [<ffffffff810eaf0b>] iput+0x20b/0x210
 [<ffffffff811b96fb>] btrfs_iget+0x1eb/0x4a0
 [<ffffffff811c3ad6>] btrfs_run_defrag_inodes+0x136/0x210
 [<ffffffff811ad55f>] cleaner_kthread+0x17f/0x1a0
 [<ffffffff81035b7d>] ? sub_preempt_count+0x9d/0xd0
 [<ffffffff811ad3e0>] ? transaction_kthread+0x280/0x280
 [<ffffffff8105af86>] kthread+0x96/0xa0
 [<ffffffff814336d4>] kernel_thread_helper+0x4/0x10
 [<ffffffff8105aef0>] ? kthread_worker_fn+0x190/0x190
 [<ffffffff814336d0>] ? gs_change+0xb/0xb
Signed-off-by: Sergei Trofimovich <slyfox@gentoo.org>
CC: Konstantin Khlebnikov <khlebnikov@openvz.org>
Tested-by: David Sterba <dsterba@suse.cz>
CC: Josef Bacik <josef@redhat.com>
CC: Chris Mason <chris.mason@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>

We can reproduce this oops via the following steps:

$ mkfs.btrfs /dev/sdb7
$ mount /dev/sdb7 /mnt/btrfs
$ for ((i=0; i<3; i++)); do btrfs sub snap /mnt/btrfs /mnt/btrfs/s_$i; done
$ rm -fr /mnt/btrfs/*
$ rm -fr /mnt/btrfs/*

then we'll get
------------[ cut here ]------------
kernel BUG at fs/btrfs/inode.c:2264!
[...]
Call Trace:
 [<ffffffffa05578c7>] btrfs_rmdir+0xf7/0x1b0 [btrfs]
 [<ffffffff81150b95>] vfs_rmdir+0xa5/0xf0
 [<ffffffff81153cc3>] do_rmdir+0x123/0x140
 [<ffffffff81145ac7>] ? fput+0x197/0x260
 [<ffffffff810aecff>] ? audit_syscall_entry+0x1bf/0x1f0
 [<ffffffff81153d0d>] sys_unlinkat+0x2d/0x40
 [<ffffffff8147896b>] system_call_fastpath+0x16/0x1b
RIP  [<ffffffffa054f7b9>] btrfs_orphan_add+0x179/0x1a0 [btrfs]

When it comes to btrfs_lookup_dentry, we may set a snapshot's inode->i_ino
to BTRFS_EMPTY_SUBVOL_DIR_OBJECTID instead of BTRFS_FIRST_FREE_OBJECTID,
while the snapshot's location.objectid remains unchanged.

However, btrfs_ino() does not take this into account, and returns a wrong ino,
and causes the oops.
Signed-off-by: Liu Bo <liubo2009@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>