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Author SHA1 Message Date
Linus Torvalds 7d6beb71da idmapped-mounts-v5.12
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Merge tag 'idmapped-mounts-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux

Pull idmapped mounts from Christian Brauner:
 "This introduces idmapped mounts which has been in the making for some
  time. Simply put, different mounts can expose the same file or
  directory with different ownership. This initial implementation comes
  with ports for fat, ext4 and with Christoph's port for xfs with more
  filesystems being actively worked on by independent people and
  maintainers.

  Idmapping mounts handle a wide range of long standing use-cases. Here
  are just a few:

   - Idmapped mounts make it possible to easily share files between
     multiple users or multiple machines especially in complex
     scenarios. For example, idmapped mounts will be used in the
     implementation of portable home directories in
     systemd-homed.service(8) where they allow users to move their home
     directory to an external storage device and use it on multiple
     computers where they are assigned different uids and gids. This
     effectively makes it possible to assign random uids and gids at
     login time.

   - It is possible to share files from the host with unprivileged
     containers without having to change ownership permanently through
     chown(2).

   - It is possible to idmap a container's rootfs and without having to
     mangle every file. For example, Chromebooks use it to share the
     user's Download folder with their unprivileged containers in their
     Linux subsystem.

   - It is possible to share files between containers with
     non-overlapping idmappings.

   - Filesystem that lack a proper concept of ownership such as fat can
     use idmapped mounts to implement discretionary access (DAC)
     permission checking.

   - They allow users to efficiently changing ownership on a per-mount
     basis without having to (recursively) chown(2) all files. In
     contrast to chown (2) changing ownership of large sets of files is
     instantenous with idmapped mounts. This is especially useful when
     ownership of a whole root filesystem of a virtual machine or
     container is changed. With idmapped mounts a single syscall
     mount_setattr syscall will be sufficient to change the ownership of
     all files.

   - Idmapped mounts always take the current ownership into account as
     idmappings specify what a given uid or gid is supposed to be mapped
     to. This contrasts with the chown(2) syscall which cannot by itself
     take the current ownership of the files it changes into account. It
     simply changes the ownership to the specified uid and gid. This is
     especially problematic when recursively chown(2)ing a large set of
     files which is commong with the aforementioned portable home
     directory and container and vm scenario.

   - Idmapped mounts allow to change ownership locally, restricting it
     to specific mounts, and temporarily as the ownership changes only
     apply as long as the mount exists.

  Several userspace projects have either already put up patches and
  pull-requests for this feature or will do so should you decide to pull
  this:

   - systemd: In a wide variety of scenarios but especially right away
     in their implementation of portable home directories.

         https://systemd.io/HOME_DIRECTORY/

   - container runtimes: containerd, runC, LXD:To share data between
     host and unprivileged containers, unprivileged and privileged
     containers, etc. The pull request for idmapped mounts support in
     containerd, the default Kubernetes runtime is already up for quite
     a while now: https://github.com/containerd/containerd/pull/4734

   - The virtio-fs developers and several users have expressed interest
     in using this feature with virtual machines once virtio-fs is
     ported.

   - ChromeOS: Sharing host-directories with unprivileged containers.

  I've tightly synced with all those projects and all of those listed
  here have also expressed their need/desire for this feature on the
  mailing list. For more info on how people use this there's a bunch of
  talks about this too. Here's just two recent ones:

      https://www.cncf.io/wp-content/uploads/2020/12/Rootless-Containers-in-Gitpod.pdf
      https://fosdem.org/2021/schedule/event/containers_idmap/

  This comes with an extensive xfstests suite covering both ext4 and
  xfs:

      https://git.kernel.org/brauner/xfstests-dev/h/idmapped_mounts

  It covers truncation, creation, opening, xattrs, vfscaps, setid
  execution, setgid inheritance and more both with idmapped and
  non-idmapped mounts. It already helped to discover an unrelated xfs
  setgid inheritance bug which has since been fixed in mainline. It will
  be sent for inclusion with the xfstests project should you decide to
  merge this.

  In order to support per-mount idmappings vfsmounts are marked with
  user namespaces. The idmapping of the user namespace will be used to
  map the ids of vfs objects when they are accessed through that mount.
  By default all vfsmounts are marked with the initial user namespace.
  The initial user namespace is used to indicate that a mount is not
  idmapped. All operations behave as before and this is verified in the
  testsuite.

  Based on prior discussions we want to attach the whole user namespace
  and not just a dedicated idmapping struct. This allows us to reuse all
  the helpers that already exist for dealing with idmappings instead of
  introducing a whole new range of helpers. In addition, if we decide in
  the future that we are confident enough to enable unprivileged users
  to setup idmapped mounts the permission checking can take into account
  whether the caller is privileged in the user namespace the mount is
  currently marked with.

  The user namespace the mount will be marked with can be specified by
  passing a file descriptor refering to the user namespace as an
  argument to the new mount_setattr() syscall together with the new
  MOUNT_ATTR_IDMAP flag. The system call follows the openat2() pattern
  of extensibility.

  The following conditions must be met in order to create an idmapped
  mount:

   - The caller must currently have the CAP_SYS_ADMIN capability in the
     user namespace the underlying filesystem has been mounted in.

   - The underlying filesystem must support idmapped mounts.

   - The mount must not already be idmapped. This also implies that the
     idmapping of a mount cannot be altered once it has been idmapped.

   - The mount must be a detached/anonymous mount, i.e. it must have
     been created by calling open_tree() with the OPEN_TREE_CLONE flag
     and it must not already have been visible in the filesystem.

  The last two points guarantee easier semantics for userspace and the
  kernel and make the implementation significantly simpler.

  By default vfsmounts are marked with the initial user namespace and no
  behavioral or performance changes are observed.

  The manpage with a detailed description can be found here:

      1d7b902e28

  In order to support idmapped mounts, filesystems need to be changed
  and mark themselves with the FS_ALLOW_IDMAP flag in fs_flags. The
  patches to convert individual filesystem are not very large or
  complicated overall as can be seen from the included fat, ext4, and
  xfs ports. Patches for other filesystems are actively worked on and
  will be sent out separately. The xfstestsuite can be used to verify
  that port has been done correctly.

  The mount_setattr() syscall is motivated independent of the idmapped
  mounts patches and it's been around since July 2019. One of the most
  valuable features of the new mount api is the ability to perform
  mounts based on file descriptors only.

  Together with the lookup restrictions available in the openat2()
  RESOLVE_* flag namespace which we added in v5.6 this is the first time
  we are close to hardened and race-free (e.g. symlinks) mounting and
  path resolution.

  While userspace has started porting to the new mount api to mount
  proper filesystems and create new bind-mounts it is currently not
  possible to change mount options of an already existing bind mount in
  the new mount api since the mount_setattr() syscall is missing.

  With the addition of the mount_setattr() syscall we remove this last
  restriction and userspace can now fully port to the new mount api,
  covering every use-case the old mount api could. We also add the
  crucial ability to recursively change mount options for a whole mount
  tree, both removing and adding mount options at the same time. This
  syscall has been requested multiple times by various people and
  projects.

  There is a simple tool available at

      https://github.com/brauner/mount-idmapped

  that allows to create idmapped mounts so people can play with this
  patch series. I'll add support for the regular mount binary should you
  decide to pull this in the following weeks:

  Here's an example to a simple idmapped mount of another user's home
  directory:

	u1001@f2-vm:/$ sudo ./mount --idmap both:1000:1001:1 /home/ubuntu/ /mnt

	u1001@f2-vm:/$ ls -al /home/ubuntu/
	total 28
	drwxr-xr-x 2 ubuntu ubuntu 4096 Oct 28 22:07 .
	drwxr-xr-x 4 root   root   4096 Oct 28 04:00 ..
	-rw------- 1 ubuntu ubuntu 3154 Oct 28 22:12 .bash_history
	-rw-r--r-- 1 ubuntu ubuntu  220 Feb 25  2020 .bash_logout
	-rw-r--r-- 1 ubuntu ubuntu 3771 Feb 25  2020 .bashrc
	-rw-r--r-- 1 ubuntu ubuntu  807 Feb 25  2020 .profile
	-rw-r--r-- 1 ubuntu ubuntu    0 Oct 16 16:11 .sudo_as_admin_successful
	-rw------- 1 ubuntu ubuntu 1144 Oct 28 00:43 .viminfo

	u1001@f2-vm:/$ ls -al /mnt/
	total 28
	drwxr-xr-x  2 u1001 u1001 4096 Oct 28 22:07 .
	drwxr-xr-x 29 root  root  4096 Oct 28 22:01 ..
	-rw-------  1 u1001 u1001 3154 Oct 28 22:12 .bash_history
	-rw-r--r--  1 u1001 u1001  220 Feb 25  2020 .bash_logout
	-rw-r--r--  1 u1001 u1001 3771 Feb 25  2020 .bashrc
	-rw-r--r--  1 u1001 u1001  807 Feb 25  2020 .profile
	-rw-r--r--  1 u1001 u1001    0 Oct 16 16:11 .sudo_as_admin_successful
	-rw-------  1 u1001 u1001 1144 Oct 28 00:43 .viminfo

	u1001@f2-vm:/$ touch /mnt/my-file

	u1001@f2-vm:/$ setfacl -m u:1001:rwx /mnt/my-file

	u1001@f2-vm:/$ sudo setcap -n 1001 cap_net_raw+ep /mnt/my-file

	u1001@f2-vm:/$ ls -al /mnt/my-file
	-rw-rwxr--+ 1 u1001 u1001 0 Oct 28 22:14 /mnt/my-file

	u1001@f2-vm:/$ ls -al /home/ubuntu/my-file
	-rw-rwxr--+ 1 ubuntu ubuntu 0 Oct 28 22:14 /home/ubuntu/my-file

	u1001@f2-vm:/$ getfacl /mnt/my-file
	getfacl: Removing leading '/' from absolute path names
	# file: mnt/my-file
	# owner: u1001
	# group: u1001
	user::rw-
	user:u1001:rwx
	group::rw-
	mask::rwx
	other::r--

	u1001@f2-vm:/$ getfacl /home/ubuntu/my-file
	getfacl: Removing leading '/' from absolute path names
	# file: home/ubuntu/my-file
	# owner: ubuntu
	# group: ubuntu
	user::rw-
	user:ubuntu:rwx
	group::rw-
	mask::rwx
	other::r--"

* tag 'idmapped-mounts-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux: (41 commits)
  xfs: remove the possibly unused mp variable in xfs_file_compat_ioctl
  xfs: support idmapped mounts
  ext4: support idmapped mounts
  fat: handle idmapped mounts
  tests: add mount_setattr() selftests
  fs: introduce MOUNT_ATTR_IDMAP
  fs: add mount_setattr()
  fs: add attr_flags_to_mnt_flags helper
  fs: split out functions to hold writers
  namespace: only take read lock in do_reconfigure_mnt()
  mount: make {lock,unlock}_mount_hash() static
  namespace: take lock_mount_hash() directly when changing flags
  nfs: do not export idmapped mounts
  overlayfs: do not mount on top of idmapped mounts
  ecryptfs: do not mount on top of idmapped mounts
  ima: handle idmapped mounts
  apparmor: handle idmapped mounts
  fs: make helpers idmap mount aware
  exec: handle idmapped mounts
  would_dump: handle idmapped mounts
  ...
2021-02-23 13:39:45 -08:00
Naohiro Aota 138082f366 btrfs: extend btrfs_rmap_block for specifying a device
btrfs_rmap_block currently reverse-maps the physical addresses on all
devices to the corresponding logical addresses.

Extend the function to match to a specified device. The old functionality
of querying all devices is left intact by specifying NULL as target
device.

A block_device instead of a btrfs_device is passed into btrfs_rmap_block,
as this function is intended to reverse-map the result of a bio, which
only has a block_device.

Also export the function for later use.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-02-09 02:46:05 +01:00
Christian Brauner 21cb47be6f
inode: make init and permission helpers idmapped mount aware
The inode_owner_or_capable() helper determines whether the caller is the
owner of the inode or is capable with respect to that inode. Allow it to
handle idmapped mounts. If the inode is accessed through an idmapped
mount it according to the mount's user namespace. Afterwards the checks
are identical to non-idmapped mounts. If the initial user namespace is
passed nothing changes so non-idmapped mounts will see identical
behavior as before.

Similarly, allow the inode_init_owner() helper to handle idmapped
mounts. It initializes a new inode on idmapped mounts by mapping the
fsuid and fsgid of the caller from the mount's user namespace. If the
initial user namespace is passed nothing changes so non-idmapped mounts
will see identical behavior as before.

Link: https://lore.kernel.org/r/20210121131959.646623-7-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2021-01-24 14:27:16 +01:00
Josef Bacik 675a4fc8f3 btrfs: tests: initialize test inodes location
I noticed that sometimes the module failed to load because the self
tests failed like this:

  BTRFS: selftest: fs/btrfs/tests/inode-tests.c:963 miscount, wanted 1, got 0

This turned out to be because sometimes the btrfs ino would be the btree
inode number, and thus we'd skip calling the set extent delalloc bit
helper, and thus not adjust ->outstanding_extents.

Fix this by making sure we initialize test inodes with a valid inode
number so that we don't get random failures during self tests.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-12-18 14:59:49 +01:00
David Sterba fa598b0696 btrfs: remove recalc_thresholds from free space ops
After removing the inode number cache that was using the free space
cache code, we can remove at least the recalc_thresholds callback from
the ops. Both code and tests use the same callback function. It's moved
before its first use.

The use_bitmaps callback is still needed by tests to create some
extents/bitmap setup.

Signed-off-by: David Sterba <dsterba@suse.com>
2020-12-09 19:16:06 +01:00
Qu Wenruo b1d51f67c9 btrfs: tests: remove invalid extent-io test
In extent-io-test, there are two invalid tests:

- Invalid nodesize for test_eb_bitmaps()
  Instead of the sectorsize and nodesize combination passed in, we're
  always using hand-crafted nodesize, e.g:

	len = (sectorsize < BTRFS_MAX_METADATA_BLOCKSIZE)
		? sectorsize * 4 : sectorsize;

  In above case, if we have 32K page size, then we will get a length of
  128K, which is beyond max node size, and obviously invalid.

  The common page size goes up to 64K so we haven't hit that

- Invalid extent buffer bytenr
  For 64K page size, the only combination we're going to test is
  sectorsize = nodesize = 64K.
  However, in that case we will try to test an eb which bytenr is not
  sectorsize aligned:

	/* Do it over again with an extent buffer which isn't page-aligned. */
	eb = __alloc_dummy_extent_buffer(fs_info, nodesize / 2, len);

  Sector alignment is a hard requirement for any sector size.
  The only exception is superblock. But anything else should follow
  sector size alignment.

  This is definitely an invalid test case.

This patch will fix both problems by:

- Honor the sectorsize/nodesize combination
  Now we won't bother to hand-craft the length and use it as nodesize.

- Use sectorsize as the 2nd run extent buffer start
  This would test the case where extent buffer is aligned to sectorsize
  but not always aligned to nodesize.

Please note that, later subpage related cleanup will reduce
extent_buffer::pages[] to exactly what we need, making the sector
unaligned extent buffer operations cause problems.

Since only extent_io self tests utilize this, this patch is required for
all later cleanup/refactoring.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-12-08 15:54:13 +01:00
Josef Bacik cd79909bc7 btrfs: load free space cache into a temporary ctl
The free space cache has been special in that we would load it right
away instead of farming the work off to a worker thread.  This resulted
in some weirdness that had to be taken into account for this fact,
namely that if we every found a block group being cached the fast way we
had to wait for it to finish, because we could get the cache before it
had been validated and we may throw the cache away.

To handle this particular case instead create a temporary
btrfs_free_space_ctl to load the free space cache into.  Then once we've
validated that it makes sense, copy it's contents into the actual
block_group->free_space_ctl.  This allows us to avoid the problems of
needing to wait for the caching to complete, we can clean up the discard
extent handling stuff in __load_free_space_cache, and we no longer need
to do the merge_space_tree() because the space is added one by one into
the real free_space_ctl.  This will allow further reworks of how we
handle loading the free space cache.

Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-12-08 15:54:03 +01:00
Josef Bacik b9729ce014 btrfs: locking: rip out path->leave_spinning
We no longer distinguish between blocking and spinning, so rip out all
this code.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-12-08 15:54:02 +01:00
David Sterba ab108d992b btrfs: use precalculated sectorsize_bits from fs_info
We do a lot of calculations where we divide or multiply by sectorsize.
We also know and make sure that sectorsize is a power of two, so this
means all divisions can be turned to shifts and avoid eg. expensive
u64/u32 divisions.

The type is u32 as it's more register friendly on x86_64 compared to u8
and the resulting assembly is smaller (movzbl vs movl).

There's also superblock s_blocksize_bits but it's usually one more
pointer dereference farther than fs_info.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-12-08 15:53:57 +01:00
Filipe Manana c334730988 btrfs: fix missing delalloc new bit for new delalloc ranges
When doing a buffered write, through one of the write family syscalls, we
look for ranges which currently don't have allocated extents and set the
'delalloc new' bit on them, so that we can report a correct number of used
blocks to the stat(2) syscall until delalloc is flushed and ordered extents
complete.

However there are a few other places where we can do a buffered write
against a range that is mapped to a hole (no extent allocated) and where
we do not set the 'new delalloc' bit. Those places are:

- Doing a memory mapped write against a hole;

- Cloning an inline extent into a hole starting at file offset 0;

- Calling btrfs_cont_expand() when the i_size of the file is not aligned
  to the sector size and is located in a hole. For example when cloning
  to a destination offset beyond EOF.

So after such cases, until the corresponding delalloc range is flushed and
the respective ordered extents complete, we can report an incorrect number
of blocks used through the stat(2) syscall.

In some cases we can end up reporting 0 used blocks to stat(2), which is a
particular bad value to report as it may mislead tools to think a file is
completely sparse when its i_size is not zero, making them skip reading
any data, an undesired consequence for tools such as archivers and other
backup tools, as reported a long time ago in the following thread (and
other past threads):

  https://lists.gnu.org/archive/html/bug-tar/2016-07/msg00001.html

Example reproducer:

  $ cat reproducer.sh
  #!/bin/bash

  MNT=/mnt/sdi
  DEV=/dev/sdi

  mkfs.btrfs -f $DEV > /dev/null
  # mkfs.xfs -f $DEV > /dev/null
  # mkfs.ext4 -F $DEV > /dev/null
  # mkfs.f2fs -f $DEV > /dev/null
  mount $DEV $MNT

  xfs_io -f -c "truncate 64K"   \
      -c "mmap -w 0 64K"        \
      -c "mwrite -S 0xab 0 64K" \
      -c "munmap"               \
      $MNT/foo

  blocks_used=$(stat -c %b $MNT/foo)
  echo "blocks used: $blocks_used"

  if [ $blocks_used -eq 0 ]; then
      echo "ERROR: blocks used is 0"
  fi

  umount $DEV

  $ ./reproducer.sh
  blocks used: 0
  ERROR: blocks used is 0

So move the logic that decides to set the 'delalloc bit' bit into the
function btrfs_set_extent_delalloc(), since that is what we use for all
those missing cases as well as for the cases that currently work well.

This change is also preparatory work for an upcoming patch that fixes
other problems related to tracking and reporting the number of bytes used
by an inode.

CC: stable@vger.kernel.org # 4.19+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-11-13 22:15:59 +01:00
Nikolay Borisov 905eb88bce btrfs: remove struct extent_io_ops
It's no longer used just remove the function and any related code which
was initialising it for inodes. No functional changes.

Removing 8 bytes from extent_io_tree in turn reduces size of other
structures where it is embedded, notably btrfs_inode where it reduces
size by 24 bytes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-10-07 12:13:25 +02:00
Nikolay Borisov fc0d82e103 btrfs: sink total_data parameter in setup_items_for_insert
That parameter can easily be derived based on the "data_size" and "nr"
parameters exploit this fact to simply the function's signature. No
functional changes.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-10-07 12:13:18 +02:00
Nikolay Borisov 3dc9dc8969 btrfs: eliminate total_size parameter from setup_items_for_insert
The value of this argument can be derived from the total_data as it's
simply the value of the data size + size of btrfs_items being touched.
Move the parameter calculation inside the function. This results in a
simpler interface and also a minor size reduction:

./scripts/bloat-o-meter ctree.original fs/btrfs/ctree.o
add/remove: 0/0 grow/shrink: 0/3 up/down: 0/-34 (-34)
Function                                     old     new   delta
btrfs_duplicate_item                         260     259      -1
setup_items_for_insert                      1200    1190     -10
btrfs_insert_empty_items                     177     154     -23

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-10-07 12:13:18 +02:00
Nikolay Borisov c2566f2289 btrfs: make btrfs_set_extent_delalloc take btrfs_inode
Preparation to make btrfs_dirty_pages take btrfs_inode as parameter.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27 12:55:35 +02:00
Denis Efremov 5af9d6ef3f btrfs: tests: remove if duplicate in __check_free_space_extents()
num_extents is already checked in the next if condition and can
be safely removed.

Signed-off-by: Denis Efremov <efremov@linux.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-07-27 12:55:27 +02:00
Josef Bacik c75e839414 btrfs: kill the subvol_srcu
Now that we have proper root ref counting everywhere we can kill the
subvol_srcu.

* removal of fs_info::subvol_srcu reduces size of fs_info by 1176 bytes

* the refcount_t used for the references checks for accidental 0->1
  in cases where the root lifetime would not be properly protected

* there's a leak detector for roots to catch unfreed roots at umount
  time

* SRCU served us well over the years but is was not a proper
  synchronization mechanism for some cases

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ update changelog ]
Signed-off-by: David Sterba <dsterba@suse.com>
2020-03-23 17:02:00 +01:00
Josef Bacik 4785e24fa5 btrfs: don't take an extra root ref at allocation time
Now that all the users of roots take references for them we can drop the
extra root ref we've been taking.  Before we had roots at 2 refs for the
life of the file system, one for the radix tree, and one simply for
existing.  Now that we have proper ref accounting in all places that use
roots we can drop this extra ref simply for existing as we no longer
need it.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-03-23 17:01:59 +01:00
Josef Bacik 8c38938c7b btrfs: move the root freeing stuff into btrfs_put_root
There are a few different ways to free roots, either you allocated them
yourself and you just do

free_extent_buffer(root->node);
free_extent_buffer(root->commit_node);
btrfs_put_root(root);

Which is the pattern for log roots.  Or for snapshots/subvolumes that
are being dropped you simply call btrfs_free_fs_root() which does all
the cleanup for you.

Unify this all into btrfs_put_root(), so that we don't free up things
associated with the root until the last reference is dropped.  This
makes the root freeing code much more significant.

The only caveat is at close_ctree() time we have to free the extent
buffers for all of our main roots (extent_root, chunk_root, etc) because
we have to drop the btree_inode and we'll run into issues if we hold
onto those nodes until ->kill_sb() time.  This will be addressed in the
future when we kill the btree_inode.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-03-23 17:01:59 +01:00
Josef Bacik 0024652895 btrfs: rename btrfs_put_fs_root and btrfs_grab_fs_root
We are now using these for all roots, rename them to btrfs_put_root()
and btrfs_grab_root();

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-03-23 17:01:33 +01:00
Josef Bacik bd647ce385 btrfs: add a leak check for roots
Now that we're going to start relying on getting ref counting right for
roots, add a list to track allocated roots and print out any roots that
aren't freed up at free_fs_info time.

Hide this behind CONFIG_BTRFS_DEBUG because this will just be used for
developers to verify they aren't breaking things.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-03-23 17:01:33 +01:00
Josef Bacik 8260edba67 btrfs: make the init of static elements in fs_info separate
In adding things like eb leak checking and root leak checking there were
a lot of weird corner cases that come from the fact that

  1) We do not init the fs_info until we get to open_ctree time in the
     normal case and

  2) The test infrastructure half-init's the fs_info for things that it
     needs.

This makes it really annoying to make changes because you have to add
init in two different places, have special cases for testing fs_info's
that may not have certain things initialized, and cases for fs_info's
that didn't make it to open_ctree and thus are not fully set up.

Fix this by extracting out the non-allocating init of the fs info into
it's own public function and use that to make sure we're all getting
consistent views of an allocated fs_info.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-03-23 17:01:33 +01:00
Josef Bacik 81f096edf0 btrfs: use btrfs_put_fs_root to free roots always
If we are going to track leaked roots we need to free them all the same
way, so don't kfree() roots directly, use btrfs_put_fs_root.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-03-23 17:01:32 +01:00
Nikolay Borisov 5750c37523 btrfs: Correctly handle empty trees in find_first_clear_extent_bit
Raviu reported that running his regular fs_trim segfaulted with the
following backtrace:

[  237.525947] assertion failed: prev, in ../fs/btrfs/extent_io.c:1595
[  237.525984] ------------[ cut here ]------------
[  237.525985] kernel BUG at ../fs/btrfs/ctree.h:3117!
[  237.525992] invalid opcode: 0000 [#1] SMP PTI
[  237.525998] CPU: 4 PID: 4423 Comm: fstrim Tainted: G     U     OE     5.4.14-8-vanilla #1
[  237.526001] Hardware name: ASUSTeK COMPUTER INC.
[  237.526044] RIP: 0010:assfail.constprop.58+0x18/0x1a [btrfs]
[  237.526079] Call Trace:
[  237.526120]  find_first_clear_extent_bit+0x13d/0x150 [btrfs]
[  237.526148]  btrfs_trim_fs+0x211/0x3f0 [btrfs]
[  237.526184]  btrfs_ioctl_fitrim+0x103/0x170 [btrfs]
[  237.526219]  btrfs_ioctl+0x129a/0x2ed0 [btrfs]
[  237.526227]  ? filemap_map_pages+0x190/0x3d0
[  237.526232]  ? do_filp_open+0xaf/0x110
[  237.526238]  ? _copy_to_user+0x22/0x30
[  237.526242]  ? cp_new_stat+0x150/0x180
[  237.526247]  ? do_vfs_ioctl+0xa4/0x640
[  237.526278]  ? btrfs_ioctl_get_supported_features+0x30/0x30 [btrfs]
[  237.526283]  do_vfs_ioctl+0xa4/0x640
[  237.526288]  ? __do_sys_newfstat+0x3c/0x60
[  237.526292]  ksys_ioctl+0x70/0x80
[  237.526297]  __x64_sys_ioctl+0x16/0x20
[  237.526303]  do_syscall_64+0x5a/0x1c0
[  237.526310]  entry_SYSCALL_64_after_hwframe+0x49/0xbe

That was due to btrfs_fs_device::aloc_tree being empty. Initially I
thought this wasn't possible and as a percaution have put the assert in
find_first_clear_extent_bit. Turns out this is indeed possible and could
happen when a file system with SINGLE data/metadata profile has a 2nd
device added. Until balance is run or a new chunk is allocated on this
device it will be completely empty.

In this case find_first_clear_extent_bit should return the full range
[0, -1ULL] and let the caller handle this i.e for trim the end will be
capped at the size of actual device.

Link: https://lore.kernel.org/linux-btrfs/izW2WNyvy1dEDweBICizKnd2KDwDiDyY2EYQr4YCwk7pkuIpthx-JRn65MPBde00ND6V0_Lh8mW0kZwzDiLDv25pUYWxkskWNJnVP0kgdMA=@protonmail.com/
Fixes: 45bfcfc168 ("btrfs: Implement find_first_clear_extent_bit")
CC: stable@vger.kernel.org # 5.2+
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-01-31 14:01:29 +01:00
Filipe Manana 7227ff4de5 Btrfs: fix race between adding and putting tree mod seq elements and nodes
There is a race between adding and removing elements to the tree mod log
list and rbtree that can lead to use-after-free problems.

Consider the following example that explains how/why the problems happens:

1) Task A has mod log element with sequence number 200. It currently is
   the only element in the mod log list;

2) Task A calls btrfs_put_tree_mod_seq() because it no longer needs to
   access the tree mod log. When it enters the function, it initializes
   'min_seq' to (u64)-1. Then it acquires the lock 'tree_mod_seq_lock'
   before checking if there are other elements in the mod seq list.
   Since the list it empty, 'min_seq' remains set to (u64)-1. Then it
   unlocks the lock 'tree_mod_seq_lock';

3) Before task A acquires the lock 'tree_mod_log_lock', task B adds
   itself to the mod seq list through btrfs_get_tree_mod_seq() and gets a
   sequence number of 201;

4) Some other task, name it task C, modifies a btree and because there
   elements in the mod seq list, it adds a tree mod elem to the tree
   mod log rbtree. That node added to the mod log rbtree is assigned
   a sequence number of 202;

5) Task B, which is doing fiemap and resolving indirect back references,
   calls btrfs get_old_root(), with 'time_seq' == 201, which in turn
   calls tree_mod_log_search() - the search returns the mod log node
   from the rbtree with sequence number 202, created by task C;

6) Task A now acquires the lock 'tree_mod_log_lock', starts iterating
   the mod log rbtree and finds the node with sequence number 202. Since
   202 is less than the previously computed 'min_seq', (u64)-1, it
   removes the node and frees it;

7) Task B still has a pointer to the node with sequence number 202, and
   it dereferences the pointer itself and through the call to
   __tree_mod_log_rewind(), resulting in a use-after-free problem.

This issue can be triggered sporadically with the test case generic/561
from fstests, and it happens more frequently with a higher number of
duperemove processes. When it happens to me, it either freezes the VM or
it produces a trace like the following before crashing:

  [ 1245.321140] general protection fault: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC PTI
  [ 1245.321200] CPU: 1 PID: 26997 Comm: pool Not tainted 5.5.0-rc6-btrfs-next-52 #1
  [ 1245.321235] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-0-ga698c8995f-prebuilt.qemu.org 04/01/2014
  [ 1245.321287] RIP: 0010:rb_next+0x16/0x50
  [ 1245.321307] Code: ....
  [ 1245.321372] RSP: 0018:ffffa151c4d039b0 EFLAGS: 00010202
  [ 1245.321388] RAX: 6b6b6b6b6b6b6b6b RBX: ffff8ae221363c80 RCX: 6b6b6b6b6b6b6b6b
  [ 1245.321409] RDX: 0000000000000001 RSI: 0000000000000000 RDI: ffff8ae221363c80
  [ 1245.321439] RBP: ffff8ae20fcc4688 R08: 0000000000000002 R09: 0000000000000000
  [ 1245.321475] R10: ffff8ae20b120910 R11: 00000000243f8bb1 R12: 0000000000000038
  [ 1245.321506] R13: ffff8ae221363c80 R14: 000000000000075f R15: ffff8ae223f762b8
  [ 1245.321539] FS:  00007fdee1ec7700(0000) GS:ffff8ae236c80000(0000) knlGS:0000000000000000
  [ 1245.321591] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  [ 1245.321614] CR2: 00007fded4030c48 CR3: 000000021da16003 CR4: 00000000003606e0
  [ 1245.321642] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  [ 1245.321668] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  [ 1245.321706] Call Trace:
  [ 1245.321798]  __tree_mod_log_rewind+0xbf/0x280 [btrfs]
  [ 1245.321841]  btrfs_search_old_slot+0x105/0xd00 [btrfs]
  [ 1245.321877]  resolve_indirect_refs+0x1eb/0xc60 [btrfs]
  [ 1245.321912]  find_parent_nodes+0x3dc/0x11b0 [btrfs]
  [ 1245.321947]  btrfs_check_shared+0x115/0x1c0 [btrfs]
  [ 1245.321980]  ? extent_fiemap+0x59d/0x6d0 [btrfs]
  [ 1245.322029]  extent_fiemap+0x59d/0x6d0 [btrfs]
  [ 1245.322066]  do_vfs_ioctl+0x45a/0x750
  [ 1245.322081]  ksys_ioctl+0x70/0x80
  [ 1245.322092]  ? trace_hardirqs_off_thunk+0x1a/0x1c
  [ 1245.322113]  __x64_sys_ioctl+0x16/0x20
  [ 1245.322126]  do_syscall_64+0x5c/0x280
  [ 1245.322139]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
  [ 1245.322155] RIP: 0033:0x7fdee3942dd7
  [ 1245.322177] Code: ....
  [ 1245.322258] RSP: 002b:00007fdee1ec6c88 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
  [ 1245.322294] RAX: ffffffffffffffda RBX: 00007fded40210d8 RCX: 00007fdee3942dd7
  [ 1245.322314] RDX: 00007fded40210d8 RSI: 00000000c020660b RDI: 0000000000000004
  [ 1245.322337] RBP: 0000562aa89e7510 R08: 0000000000000000 R09: 00007fdee1ec6d44
  [ 1245.322369] R10: 0000000000000073 R11: 0000000000000246 R12: 00007fdee1ec6d48
  [ 1245.322390] R13: 00007fdee1ec6d40 R14: 00007fded40210d0 R15: 00007fdee1ec6d50
  [ 1245.322423] Modules linked in: ....
  [ 1245.323443] ---[ end trace 01de1e9ec5dff3cd ]---

Fix this by ensuring that btrfs_put_tree_mod_seq() computes the minimum
sequence number and iterates the rbtree while holding the lock
'tree_mod_log_lock' in write mode. Also get rid of the 'tree_mod_seq_lock'
lock, since it is now redundant.

Fixes: bd989ba359 ("Btrfs: add tree modification log functions")
Fixes: 097b8a7c9e ("Btrfs: join tree mod log code with the code holding back delayed refs")
CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-01-31 14:01:20 +01:00
Nikolay Borisov bf2e2eb060 btrfs: Add self-tests for btrfs_rmap_block
Add RAID1 and single testcases to verify that data stripes are excluded
from super block locations and that the address mapping is valid.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ update changelog ]
Signed-off-by: David Sterba <dsterba@suse.com>
2020-01-23 17:24:35 +01:00
Nikolay Borisov b3ad2c17fd btrfs: selftests: Add support for dummy devices
Add basic infrastructure to create and link dummy btrfs_devices. This
will be used in the pending btrfs_rmap_block test which deals with
the block groups.

Calling btrfs_alloc_dummy_device will link the newly created device to
the passed fs_info and the test framework will free them once the test
is finished.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-01-23 17:24:34 +01:00
Omar Sandoval 39b07b5d70 btrfs: drop create parameter to btrfs_get_extent()
We only pass this as 1 from __extent_writepage_io(). The parameter
basically means "pretend I didn't pass in a page". This is silly since
we can simply not pass in the page. Get rid of the parameter from
btrfs_get_extent(), and since it's used as a get_extent_t callback,
remove it from get_extent_t and btree_get_extent(), neither of which
need it.

While we're here, let's document btrfs_get_extent().

Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-01-20 16:40:55 +01:00
Dan Carpenter b6293c821e btrfs: return error pointer from alloc_test_extent_buffer
Callers of alloc_test_extent_buffer have not correctly interpreted the
return value as error pointer, as alloc_test_extent_buffer should behave
as alloc_extent_buffer. The self-tests were unaffected but
btrfs_find_create_tree_block could call both functions and that would
cause problems up in the call chain.

Fixes: faa2dbf004 ("Btrfs: add sanity tests for new qgroup accounting code")
CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-12-13 14:09:24 +01:00
David Sterba 32da5386d9 btrfs: rename btrfs_block_group_cache
The type name is misleading, a single entry is named 'cache' while this
normally means a collection of objects. Rename that everywhere. Also the
identifier was quite long, making function prototypes harder to format.

Suggested-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-11-18 17:51:51 +01:00
David Sterba b3470b5dbe btrfs: add dedicated members for start and length of a block group
The on-disk format of block group item makes use of the key that stores
the offset and length. This is further used in the code, although this
makes thing harder to understand. The key is also packed so the
offset/length is not properly aligned as u64.

Add start (key.objectid) and length (key.offset) members to block group
and remove the embedded key.  When the item is searched or written, a
local variable for key is used.

Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-11-18 17:51:45 +01:00
Filipe Manana 9f7fec0ba8 Btrfs: fix selftests failure due to uninitialized i_mode in test inodes
Some of the self tests create a test inode, setup some extents and then do
calls to btrfs_get_extent() to test that the corresponding extent maps
exist and are correct. However btrfs_get_extent(), since the 5.2 merge
window, now errors out when it finds a regular or prealloc extent for an
inode that does not correspond to a regular file (its ->i_mode is not
S_IFREG). This causes the self tests to fail sometimes, specially when
KASAN, slub_debug and page poisoning are enabled:

  $ modprobe btrfs
  modprobe: ERROR: could not insert 'btrfs': Invalid argument

  $ dmesg
  [ 9414.691648] Btrfs loaded, crc32c=crc32c-intel, debug=on, assert=on, integrity-checker=on, ref-verify=on
  [ 9414.692655] BTRFS: selftest: sectorsize: 4096  nodesize: 4096
  [ 9414.692658] BTRFS: selftest: running btrfs free space cache tests
  [ 9414.692918] BTRFS: selftest: running extent only tests
  [ 9414.693061] BTRFS: selftest: running bitmap only tests
  [ 9414.693366] BTRFS: selftest: running bitmap and extent tests
  [ 9414.696455] BTRFS: selftest: running space stealing from bitmap to extent tests
  [ 9414.697131] BTRFS: selftest: running extent buffer operation tests
  [ 9414.697133] BTRFS: selftest: running btrfs_split_item tests
  [ 9414.697564] BTRFS: selftest: running extent I/O tests
  [ 9414.697583] BTRFS: selftest: running find delalloc tests
  [ 9415.081125] BTRFS: selftest: running find_first_clear_extent_bit test
  [ 9415.081278] BTRFS: selftest: running extent buffer bitmap tests
  [ 9415.124192] BTRFS: selftest: running inode tests
  [ 9415.124195] BTRFS: selftest: running btrfs_get_extent tests
  [ 9415.127909] BTRFS: selftest: running hole first btrfs_get_extent test
  [ 9415.128343] BTRFS critical (device (efault)): regular/prealloc extent found for non-regular inode 256
  [ 9415.131428] BTRFS: selftest: fs/btrfs/tests/inode-tests.c:904 expected a real extent, got 0

This happens because the test inodes are created without ever initializing
the i_mode field of the inode, and neither VFS's new_inode() nor the btrfs
callback btrfs_alloc_inode() initialize the i_mode. Initialization of the
i_mode is done through the various callbacks used by the VFS to create
new inodes (regular files, directories, symlinks, tmpfiles, etc), which
all call btrfs_new_inode() which in turn calls inode_init_owner(), which
sets the inode's i_mode. Since the tests only uses new_inode() to create
the test inodes, the i_mode was never initialized.

This always happens on a VM I used with kasan, slub_debug and many other
debug facilities enabled. It also happened to someone who reported this
on bugzilla (on a 5.3-rc).

Fix this by setting i_mode to S_IFREG at btrfs_new_test_inode().

Fixes: 6bf9e4bd6a ("btrfs: inode: Verify inode mode to avoid NULL pointer dereference")
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=204397
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-24 14:45:02 +02:00
Omar Sandoval e182163d9c btrfs: stop clearing EXTENT_DIRTY in inode I/O tree
Since commit fee187d9d9 ("Btrfs: do not set EXTENT_DIRTY along with
EXTENT_DELALLOC"), we never set EXTENT_DIRTY in inode->io_tree, so we
can simplify and stop trying to clear it.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:59:17 +02:00
Filipe Manana 202f64ef42 Btrfs: make test_find_first_clear_extent_bit fail on incorrect results
If any call to find_first_clear_extent_bit() returns an unexpected result,
the test should fail and not just print an error message, otherwise it
makes detection of regressions much harder to notice.

Fixes: 1eaebb341d ("btrfs: Don't trim returned range based on input value in find_first_clear_extent_bit")
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:59:05 +02:00
Filipe Manana cdf52bd9fe Btrfs: fix memory leaks in the test test_find_first_clear_extent_bit
The test creates an extent io tree and sets several ranges with the
CHUNK_ALLOCATED and CHUNK_TRIMMED bits, resulting in the allocation of
several extent state structures. However the test never clears those
ranges, resulting in memory leaks of the extent state structures.

This is detected when CONFIG_BTRFS_DEBUG is set once we remove the
btrfs module (rmmod btrfs):

[57399.787918] BTRFS: state leak: start 67108864 end 75497471 state 1 in tree 1 refs 1
[57399.790155] BTRFS: state leak: start 33554432 end 67108863 state 33 in tree 1 refs 1
[57399.791941] BTRFS: state leak: start 1048576 end 4194303 state 33 in tree 1 refs 1
[57399.793753] BTRFS: state leak: start 67108864 end 75497471 state 1 in tree 1 refs 1
[57399.795188] BTRFS: state leak: start 33554432 end 67108863 state 33 in tree 1 refs 1
[57399.796453] BTRFS: state leak: start 1048576 end 4194303 state 33 in tree 1 refs 1
[57399.797765] BTRFS: state leak: start 67108864 end 75497471 state 1 in tree 1 refs 1
[57399.799049] BTRFS: state leak: start 33554432 end 67108863 state 33 in tree 1 refs 1
[57399.800142] BTRFS: state leak: start 1048576 end 4194303 state 33 in tree 1 refs 1
[57399.801126] BTRFS: state leak: start 67108864 end 75497471 state 1 in tree 1 refs 1
[57399.802106] BTRFS: state leak: start 33554432 end 67108863 state 33 in tree 1 refs 1
[57399.803119] BTRFS: state leak: start 1048576 end 4194303 state 33 in tree 1 refs 1
[57399.804153] BTRFS: state leak: start 67108864 end 75497471 state 1 in tree 1 refs 1
[57399.805196] BTRFS: state leak: start 33554432 end 67108863 state 33 in tree 1 refs 1
[57399.806191] BTRFS: state leak: start 1048576 end 4194303 state 33 in tree 1 refs 1

The start and end offsets reported correspond exactly to the ranges
used by the test.

So fix that by clearing all the ranges when the test finishes.

Fixes: 1eaebb341d ("btrfs: Don't trim returned range based on input value in find_first_clear_extent_bit")
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:59:05 +02:00
Josef Bacik aac0023c21 btrfs: move basic block_group definitions to their own header
This is prep work for moving all of the block group cache code into its
own file.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ minor comment updates ]
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:59:03 +02:00
Nikolay Borisov 330a582790 btrfs: Remove leftover of in-band dedupe
It's unlikely in-band dedupe is going to land so just remove any
leftovers - dedupe.h header as well as the 'dedupe' parameter to
btrfs_set_extent_delalloc.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-09-09 14:58:59 +02:00
Linus Torvalds 933a90bf4f Merge branch 'work.mount0' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs mount updates from Al Viro:
 "The first part of mount updates.

  Convert filesystems to use the new mount API"

* 'work.mount0' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (63 commits)
  mnt_init(): call shmem_init() unconditionally
  constify ksys_mount() string arguments
  don't bother with registering rootfs
  init_rootfs(): don't bother with init_ramfs_fs()
  vfs: Convert smackfs to use the new mount API
  vfs: Convert selinuxfs to use the new mount API
  vfs: Convert securityfs to use the new mount API
  vfs: Convert apparmorfs to use the new mount API
  vfs: Convert openpromfs to use the new mount API
  vfs: Convert xenfs to use the new mount API
  vfs: Convert gadgetfs to use the new mount API
  vfs: Convert oprofilefs to use the new mount API
  vfs: Convert ibmasmfs to use the new mount API
  vfs: Convert qib_fs/ipathfs to use the new mount API
  vfs: Convert efivarfs to use the new mount API
  vfs: Convert configfs to use the new mount API
  vfs: Convert binfmt_misc to use the new mount API
  convenience helper: get_tree_single()
  convenience helper get_tree_nodev()
  vfs: Kill sget_userns()
  ...
2019-07-19 10:42:02 -07:00
Goldwyn Rodrigues 9978059be8 btrfs: Evaluate io_tree in find_lock_delalloc_range()
Simplification.  No point passing the tree variable when it can be
evaluated from inode. The tests now use the io_tree from btrfs_inode as
opposed to creating one.

Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-07-04 17:26:17 +02:00
David Sterba 93ead46b03 btrfs: tests: add locks around add_extent_mapping
There are no concerns about locking during the selftests so the locks
are not necessary, but following patches will add lockdep assertions to
add_extent_mapping so this is needed in tests too.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-07-01 13:35:03 +02:00
Nikolay Borisov 1eaebb341d btrfs: Don't trim returned range based on input value in find_first_clear_extent_bit
Currently find_first_clear_extent_bit always returns a range whose
starting value is >= passed 'start'. This implicit trimming behavior is
somewhat subtle and an implementation detail.

Instead, this patch modifies the function such that now it always
returns the range which contains passed 'start' and has the given bits
unset. This range could either be due to presence of existing records
which contains 'start' but have the bits unset or because there are no
records that contain the given starting offset.

This patch also adds test cases which cover find_first_clear_extent_bit
since they were missing up until now.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-07-01 13:35:02 +02:00
David Howells 389e22fb46 vfs: Convert btrfs_test to use the new mount API
Convert the btrfs_test filesystem to the new internal mount API as the old
one will be obsoleted and removed.  This allows greater flexibility in
communication of mount parameters between userspace, the VFS and the
filesystem.

See Documentation/filesystems/mount_api.txt for more information.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: David Sterba <dsterba@suse.com>
cc: Chris Mason <clm@fb.com>
cc: Josef Bacik <josef@toxicpanda.com>
cc: linux-btrfs@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-05-25 18:06:16 -04:00
Al Viro 1f58bb18f6 mount_pseudo(): drop 'name' argument, switch to d_make_root()
Once upon a time we used to set ->d_name of e.g. pipefs root
so that d_path() on pipes would work.  These days it's
completely pointless - dentries of pipes are not even connected
to pipefs root.  However, mount_pseudo() had set the root
dentry name (passed as the second argument) and callers
kept inventing names to pass to it.  Including those that
didn't *have* any non-root dentries to start with...

All of that had been pointless for about 8 years now; it's
time to get rid of that cargo-culting...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-05-25 17:59:24 -04:00
Linus Torvalds 9f2e3a53f7 for-5.2-tag
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Merge tag 'for-5.2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs updates from David Sterba:
 "This time the majority of changes are cleanups, though there's still a
  number of changes of user interest.

  User visible changes:

   - better read time and write checks to catch errors early and before
     writing data to disk (to catch potential memory corruption on data
     that get checksummed)

   - qgroups + metadata relocation: last speed up patch int the series
     to address the slowness, there should be no overhead comparing
     balance with and without qgroups

   - FIEMAP ioctl does not start a transaction unnecessarily, this can
     result in a speed up and less blocking due to IO

   - LOGICAL_INO (v1, v2) does not start transaction unnecessarily, this
     can speed up the mentioned ioctl and scrub as well

   - fsync on files with many (but not too many) hardlinks is faster,
     finer decision if the links should be fsynced individually or
     completely

   - send tries harder to find ranges to clone

   - trim/discard will skip unallocated chunks that haven't been touched
     since the last mount

  Fixes:

   - send flushes delayed allocation before start, otherwise it could
     miss some changes in case of a very recent rw->ro switch of a
     subvolume

   - fix fallocate with qgroups that could lead to space accounting
     underflow, reported as a warning

   - trim/discard ioctl honours the requested range

   - starting send and dedupe on a subvolume at the same time will let
     only one of them succeed, this is to prevent changes that send
     could miss due to dedupe; both operations are restartable

  Core changes:

   - more tree-checker validations, errors reported by fuzzing tools:
      - device item
      - inode item
      - block group profiles

   - tracepoints for extent buffer locking

   - async cow preallocates memory to avoid errors happening too deep in
     the call chain

   - metadata reservations for delalloc reworked to better adapt in
     many-writers/low-space scenarios

   - improved space flushing logic for intense DIO vs buffered workloads

   - lots of cleanups
      - removed unused struct members
      - redundant argument removal
      - properties and xattrs
      - extent buffer locking
      - selftests
      - use common file type conversions
      - many-argument functions reduction"

* tag 'for-5.2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: (227 commits)
  btrfs: Use kvmalloc for allocating compressed path context
  btrfs: Factor out common extent locking code in submit_compressed_extents
  btrfs: Set io_tree only once in submit_compressed_extents
  btrfs: Replace clear_extent_bit with unlock_extent
  btrfs: Make compress_file_range take only struct async_chunk
  btrfs: Remove fs_info from struct async_chunk
  btrfs: Rename async_cow to async_chunk
  btrfs: Preallocate chunks in cow_file_range_async
  btrfs: reserve delalloc metadata differently
  btrfs: track DIO bytes in flight
  btrfs: merge calls of btrfs_setxattr and btrfs_setxattr_trans in btrfs_set_prop
  btrfs: delete unused function btrfs_set_prop_trans
  btrfs: start transaction in xattr_handler_set_prop
  btrfs: drop local copy of inode i_mode
  btrfs: drop old_fsflags in btrfs_ioctl_setflags
  btrfs: modify local copy of btrfs_inode flags
  btrfs: drop useless inode i_flags copy and restore
  btrfs: start transaction in btrfs_ioctl_setflags()
  btrfs: export btrfs_set_prop
  btrfs: refactor btrfs_set_props to validate externally
  ...
2019-05-07 11:34:19 -07:00
David Sterba 2ccf545e0d btrfs: get fs_info from block group in search_free_space_info
We can read fs_info from the block group cache structure and can drop it
from the parameters.  Though the transaction is also availabe, it's not
guaranteed to be non-NULL.

Signed-off-by: David Sterba <dsterba@suse.com>
2019-04-29 19:02:46 +02:00
Qu Wenruo 6bf9e4bd6a btrfs: inode: Verify inode mode to avoid NULL pointer dereference
[BUG]
When accessing a file on a crafted image, btrfs can crash in block layer:

  BUG: unable to handle kernel NULL pointer dereference at 0000000000000008
  PGD 136501067 P4D 136501067 PUD 124519067 PMD 0
  CPU: 3 PID: 0 Comm: swapper/3 Not tainted 5.0.0-rc8-default #252
  RIP: 0010:end_bio_extent_readpage+0x144/0x700
  Call Trace:
   <IRQ>
   blk_update_request+0x8f/0x350
   blk_mq_end_request+0x1a/0x120
   blk_done_softirq+0x99/0xc0
   __do_softirq+0xc7/0x467
   irq_exit+0xd1/0xe0
   call_function_single_interrupt+0xf/0x20
   </IRQ>
  RIP: 0010:default_idle+0x1e/0x170

[CAUSE]
The crafted image has a tricky corruption, the INODE_ITEM has a
different type against its parent dir:

        item 20 key (268 INODE_ITEM 0) itemoff 2808 itemsize 160
                generation 13 transid 13 size 1048576 nbytes 1048576
                block group 0 mode 121644 links 1 uid 0 gid 0 rdev 0
                sequence 9 flags 0x0(none)

This mode number 0120000 means it's a symlink.

But the dir item think it's still a regular file:

        item 8 key (264 DIR_INDEX 5) itemoff 3707 itemsize 32
                location key (268 INODE_ITEM 0) type FILE
                transid 13 data_len 0 name_len 2
                name: f4
        item 40 key (264 DIR_ITEM 51821248) itemoff 1573 itemsize 32
                location key (268 INODE_ITEM 0) type FILE
                transid 13 data_len 0 name_len 2
                name: f4

For symlink, we don't set BTRFS_I(inode)->io_tree.ops and leave it
empty, as symlink is only designed to have inlined extent, all handled
by tree block read.  Thus no need to trigger btrfs_submit_bio_hook() for
inline file extent.

However end_bio_extent_readpage() expects tree->ops populated, as it's
reading regular data extent.  This causes NULL pointer dereference.

[FIX]
This patch fixes the problem in two ways:

- Verify inode mode against its dir item when looking up inode
  So in btrfs_lookup_dentry() if we find inode mode mismatch with dir
  item, we error out so that corrupted inode will not be accessed.

- Verify inode mode when getting extent mapping
  Only regular file should have regular or preallocated extent.
  If we found regular/preallocated file extent for symlink or
  the rest, we error out before submitting the read bio.

With this fix that crafted image can be rejected gracefully:

  BTRFS critical (device loop0): inode mode mismatch with dir: inode mode=0121644 btrfs type=7 dir type=1

Reported-by: Yoon Jungyeon <jungyeon@gatech.edu>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=202763
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-04-29 19:02:32 +02:00
David Sterba 90b1377daa btrfs: qgroup: remove obsolete fs_info members
The commit fcebe4562d ("Btrfs: rework qgroup accounting") reworked
qgroups and added some new structures. Another rework of qgroup
mechanics e69bcee376 ("btrfs: qgroup: Cleanup the old
ref_node-oriented mechanism.") stopped using them and left uncleaned.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-04-29 19:02:31 +02:00
David Sterba e4fa7469eb btrfs: tests: unify messages when tests start
- make the messages more visually consistent and use same format
  "running ... test", any error or other warning can be easily spotted

- move some message to the test entry function

- add message to the inode tests

Example output:

[    8.187391] Btrfs loaded, crc32c=crc32c-generic, assert=on, integrity-checker=on, ref-verify=on
[    8.189476] BTRFS: selftest: sectorsize: 4096  nodesize: 4096
[    8.190761] BTRFS: selftest: running btrfs free space cache tests
[    8.192245] BTRFS: selftest: running extent only tests
[    8.193573] BTRFS: selftest: running bitmap only tests
[    8.194876] BTRFS: selftest: running bitmap and extent tests
[    8.196166] BTRFS: selftest: running space stealing from bitmap to extent tests
[    8.198026] BTRFS: selftest: running extent buffer operation tests
[    8.199328] BTRFS: selftest: running btrfs_split_item tests
[    8.200653] BTRFS: selftest: running extent I/O tests
[    8.201808] BTRFS: selftest: running find delalloc tests
[    8.320733] BTRFS: selftest: running extent buffer bitmap tests
[    8.340795] BTRFS: selftest: running inode tests
[    8.341766] BTRFS: selftest: running btrfs_get_extent tests
[    8.342981] BTRFS: selftest: running hole first btrfs_get_extent test
[    8.344342] BTRFS: selftest: running outstanding_extents tests
[    8.345575] BTRFS: selftest: running qgroup tests
[    8.346537] BTRFS: selftest: running qgroup add/remove tests
[    8.347725] BTRFS: selftest: running qgroup multiple refs test
[    8.354982] BTRFS: selftest: running free space tree tests
[    8.372175] BTRFS: selftest: sectorsize: 4096  nodesize: 8192
[    8.373539] BTRFS: selftest: running btrfs free space cache tests
[    8.374989] BTRFS: selftest: running extent only tests
[    8.376236] BTRFS: selftest: running bitmap only tests
[    8.377483] BTRFS: selftest: running bitmap and extent tests
[    8.378854] BTRFS: selftest: running space stealing from bitmap to extent tests
...

Signed-off-by: David Sterba <dsterba@suse.com>
2019-04-29 19:02:28 +02:00
David Sterba 752dbe48e2 btrfs: tests: drop messages when some tests finish
The messages like 'extent I/O tests finished' are redundant, if the test
fails it's quite obvious in the log and hang is also noticeable. No
other then extent_io and free space tree tests print that so make it
consistent.

Signed-off-by: David Sterba <dsterba@suse.com>
2019-04-29 19:02:28 +02:00
David Sterba 3173fd926c btrfs: tests: fix comments about tested extent map ranges
Comments about ranges did not match the code, the correct calculation is
to use start and start+len as the interval boundaries.

Signed-off-by: David Sterba <dsterba@suse.com>
2019-04-29 19:02:28 +02:00
David Sterba 43f7cddc6e btrfs: tests: use SZ_ constants everywhere
There are a few unconverted constants that are not powers of two and
haven't been converted.

Signed-off-by: David Sterba <dsterba@suse.com>
2019-04-29 19:02:27 +02:00