Commit Graph

3204 Commits

Author SHA1 Message Date
Andreas Gruenbacher
19fe5f643f iomap: Switch from blkno to disk offset
Replace iomap->blkno, the sector number, with iomap->addr, the disk
offset in bytes.  For invalid disk offsets, use the special value
IOMAP_NULL_ADDR instead of IOMAP_NULL_BLOCK.

This allows to use iomap for mappings which are not block aligned, such
as inline data on ext4.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>  # iomap, xfs
Reviewed-by: Jan Kara <jack@suse.cz>
2017-10-01 17:55:54 -04:00
Linus Torvalds
e253d98f5b Merge branch 'work.read_write' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull nowait read support from Al Viro:
 "Support IOCB_NOWAIT for buffered reads and block devices"

* 'work.read_write' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  block_dev: support RFW_NOWAIT on block device nodes
  fs: support RWF_NOWAIT for buffered reads
  fs: support IOCB_NOWAIT in generic_file_buffered_read
  fs: pass iocb to do_generic_file_read
2017-09-14 19:29:55 -07:00
Linus Torvalds
0f0d12728e Merge branch 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull mount flag updates from Al Viro:
 "Another chunk of fmount preparations from dhowells; only trivial
  conflicts for that part. It separates MS_... bits (very grotty
  mount(2) ABI) from the struct super_block ->s_flags (kernel-internal,
  only a small subset of MS_... stuff).

  This does *not* convert the filesystems to new constants; only the
  infrastructure is done here. The next step in that series is where the
  conflicts would be; that's the conversion of filesystems. It's purely
  mechanical and it's better done after the merge, so if you could run
  something like

	list=$(for i in MS_RDONLY MS_NOSUID MS_NODEV MS_NOEXEC MS_SYNCHRONOUS MS_MANDLOCK MS_DIRSYNC MS_NOATIME MS_NODIRATIME MS_SILENT MS_POSIXACL MS_KERNMOUNT MS_I_VERSION MS_LAZYTIME; do git grep -l $i fs drivers/staging/lustre drivers/mtd ipc mm include/linux; done|sort|uniq|grep -v '^fs/namespace.c$')

	sed -i -e 's/\<MS_RDONLY\>/SB_RDONLY/g' \
	        -e 's/\<MS_NOSUID\>/SB_NOSUID/g' \
	        -e 's/\<MS_NODEV\>/SB_NODEV/g' \
	        -e 's/\<MS_NOEXEC\>/SB_NOEXEC/g' \
	        -e 's/\<MS_SYNCHRONOUS\>/SB_SYNCHRONOUS/g' \
	        -e 's/\<MS_MANDLOCK\>/SB_MANDLOCK/g' \
	        -e 's/\<MS_DIRSYNC\>/SB_DIRSYNC/g' \
	        -e 's/\<MS_NOATIME\>/SB_NOATIME/g' \
	        -e 's/\<MS_NODIRATIME\>/SB_NODIRATIME/g' \
	        -e 's/\<MS_SILENT\>/SB_SILENT/g' \
	        -e 's/\<MS_POSIXACL\>/SB_POSIXACL/g' \
	        -e 's/\<MS_KERNMOUNT\>/SB_KERNMOUNT/g' \
	        -e 's/\<MS_I_VERSION\>/SB_I_VERSION/g' \
	        -e 's/\<MS_LAZYTIME\>/SB_LAZYTIME/g' \
	        $list

  and commit it with something along the lines of 'convert filesystems
  away from use of MS_... constants' as commit message, it would save a
  quite a bit of headache next cycle"

* 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  VFS: Differentiate mount flags (MS_*) from internal superblock flags
  VFS: Convert sb->s_flags & MS_RDONLY to sb_rdonly(sb)
  vfs: Add sb_rdonly(sb) to query the MS_RDONLY flag on s_flags
2017-09-14 18:54:01 -07:00
Linus Torvalds
89fd915c40 libnvdimm for 4.14
* Media error handling support in the Block Translation Table (BTT)
   driver is reworked to address sleeping-while-atomic locking and
   memory-allocation-context conflicts.
 
 * The dax_device lookup overhead for xfs and ext4 is moved out of the
   iomap hot-path to a mount-time lookup.
 
 * A new 'ecc_unit_size' sysfs attribute is added to advertise the
   read-modify-write boundary property of a persistent memory range.
 
 * Preparatory fix-ups for arm and powerpc pmem support are included
   along with other miscellaneous fixes.
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Merge tag 'libnvdimm-for-4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

Pull libnvdimm from Dan Williams:
 "A rework of media error handling in the BTT driver and other updates.
  It has appeared in a few -next releases and collected some late-
  breaking build-error and warning fixups as a result.

  Summary:

   - Media error handling support in the Block Translation Table (BTT)
     driver is reworked to address sleeping-while-atomic locking and
     memory-allocation-context conflicts.

   - The dax_device lookup overhead for xfs and ext4 is moved out of the
     iomap hot-path to a mount-time lookup.

   - A new 'ecc_unit_size' sysfs attribute is added to advertise the
     read-modify-write boundary property of a persistent memory range.

   - Preparatory fix-ups for arm and powerpc pmem support are included
     along with other miscellaneous fixes"

* tag 'libnvdimm-for-4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (26 commits)
  libnvdimm, btt: fix format string warnings
  libnvdimm, btt: clean up warning and error messages
  ext4: fix null pointer dereference on sbi
  libnvdimm, nfit: move the check on nd_reserved2 to the endpoint
  dax: fix FS_DAX=n BLOCK=y compilation
  libnvdimm: fix integer overflow static analysis warning
  libnvdimm, nd_blk: remove mmio_flush_range()
  libnvdimm, btt: rework error clearing
  libnvdimm: fix potential deadlock while clearing errors
  libnvdimm, btt: cache sector_size in arena_info
  libnvdimm, btt: ensure that flags were also unchanged during a map_read
  libnvdimm, btt: refactor map entry operations with macros
  libnvdimm, btt: fix a missed NVDIMM_IO_ATOMIC case in the write path
  libnvdimm, nfit: export an 'ecc_unit_size' sysfs attribute
  ext4: perform dax_device lookup at mount
  ext2: perform dax_device lookup at mount
  xfs: perform dax_device lookup at mount
  dax: introduce a fs_dax_get_by_bdev() helper
  libnvdimm, btt: check memory allocation failure
  libnvdimm, label: fix index block size calculation
  ...
2017-09-11 13:10:57 -07:00
Linus Torvalds
ae8ac6b7db Merge branch 'quota_scaling' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs
Pull quota scaling updates from Jan Kara:
 "This contains changes to make the quota subsystem more scalable.

  Reportedly it improves number of files created per second on ext4
  filesystem on fast storage by about a factor of 2x"

* 'quota_scaling' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs: (28 commits)
  quota: Add lock annotations to struct members
  quota: Reduce contention on dq_data_lock
  fs: Provide __inode_get_bytes()
  quota: Inline dquot_[re]claim_reserved_space() into callsite
  quota: Inline inode_{incr,decr}_space() into callsites
  quota: Inline functions into their callsites
  ext4: Disable dirty list tracking of dquots when journalling quotas
  quota: Allow disabling tracking of dirty dquots in a list
  quota: Remove dq_wait_unused from dquot
  quota: Move locking into clear_dquot_dirty()
  quota: Do not dirty bad dquots
  quota: Fix possible corruption of dqi_flags
  quota: Propagate ->quota_read errors from v2_read_file_info()
  quota: Fix error codes in v2_read_file_info()
  quota: Push dqio_sem down to ->read_file_info()
  quota: Push dqio_sem down to ->write_file_info()
  quota: Push dqio_sem down to ->get_next_id()
  quota: Push dqio_sem down to ->release_dqblk()
  quota: Remove locking for writing to the old quota format
  quota: Do not acquire dqio_sem for dquot overwrites in v2 format
  ...
2017-09-07 15:19:35 -07:00
Linus Torvalds
a0725ab0c7 Merge branch 'for-4.14/block' of git://git.kernel.dk/linux-block
Pull block layer updates from Jens Axboe:
 "This is the first pull request for 4.14, containing most of the code
  changes. It's a quiet series this round, which I think we needed after
  the churn of the last few series. This contains:

   - Fix for a registration race in loop, from Anton Volkov.

   - Overflow complaint fix from Arnd for DAC960.

   - Series of drbd changes from the usual suspects.

   - Conversion of the stec/skd driver to blk-mq. From Bart.

   - A few BFQ improvements/fixes from Paolo.

   - CFQ improvement from Ritesh, allowing idling for group idle.

   - A few fixes found by Dan's smatch, courtesy of Dan.

   - A warning fixup for a race between changing the IO scheduler and
     device remova. From David Jeffery.

   - A few nbd fixes from Josef.

   - Support for cgroup info in blktrace, from Shaohua.

   - Also from Shaohua, new features in the null_blk driver to allow it
     to actually hold data, among other things.

   - Various corner cases and error handling fixes from Weiping Zhang.

   - Improvements to the IO stats tracking for blk-mq from me. Can
     drastically improve performance for fast devices and/or big
     machines.

   - Series from Christoph removing bi_bdev as being needed for IO
     submission, in preparation for nvme multipathing code.

   - Series from Bart, including various cleanups and fixes for switch
     fall through case complaints"

* 'for-4.14/block' of git://git.kernel.dk/linux-block: (162 commits)
  kernfs: checking for IS_ERR() instead of NULL
  drbd: remove BIOSET_NEED_RESCUER flag from drbd_{md_,}io_bio_set
  drbd: Fix allyesconfig build, fix recent commit
  drbd: switch from kmalloc() to kmalloc_array()
  drbd: abort drbd_start_resync if there is no connection
  drbd: move global variables to drbd namespace and make some static
  drbd: rename "usermode_helper" to "drbd_usermode_helper"
  drbd: fix race between handshake and admin disconnect/down
  drbd: fix potential deadlock when trying to detach during handshake
  drbd: A single dot should be put into a sequence.
  drbd: fix rmmod cleanup, remove _all_ debugfs entries
  drbd: Use setup_timer() instead of init_timer() to simplify the code.
  drbd: fix potential get_ldev/put_ldev refcount imbalance during attach
  drbd: new disk-option disable-write-same
  drbd: Fix resource role for newly created resources in events2
  drbd: mark symbols static where possible
  drbd: Send P_NEG_ACK upon write error in protocol != C
  drbd: add explicit plugging when submitting batches
  drbd: change list_for_each_safe to while(list_first_entry_or_null)
  drbd: introduce drbd_recv_header_maybe_unplug
  ...
2017-09-07 11:59:42 -07:00
Linus Torvalds
d34fc1adf0 Merge branch 'akpm' (patches from Andrew)
Merge updates from Andrew Morton:

 - various misc bits

 - DAX updates

 - OCFS2

 - most of MM

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (119 commits)
  mm,fork: introduce MADV_WIPEONFORK
  x86,mpx: make mpx depend on x86-64 to free up VMA flag
  mm: add /proc/pid/smaps_rollup
  mm: hugetlb: clear target sub-page last when clearing huge page
  mm: oom: let oom_reap_task and exit_mmap run concurrently
  swap: choose swap device according to numa node
  mm: replace TIF_MEMDIE checks by tsk_is_oom_victim
  mm, oom: do not rely on TIF_MEMDIE for memory reserves access
  z3fold: use per-cpu unbuddied lists
  mm, swap: don't use VMA based swap readahead if HDD is used as swap
  mm, swap: add sysfs interface for VMA based swap readahead
  mm, swap: VMA based swap readahead
  mm, swap: fix swap readahead marking
  mm, swap: add swap readahead hit statistics
  mm/vmalloc.c: don't reinvent the wheel but use existing llist API
  mm/vmstat.c: fix wrong comment
  selftests/memfd: add memfd_create hugetlbfs selftest
  mm/shmem: add hugetlbfs support to memfd_create()
  mm, devm_memremap_pages: use multi-order radix for ZONE_DEVICE lookups
  mm/vmalloc.c: halve the number of comparisons performed in pcpu_get_vm_areas()
  ...
2017-09-06 20:49:49 -07:00
Jan Kara
397162ffa2 mm: remove nr_pages argument from pagevec_lookup{,_range}()
All users of pagevec_lookup() and pagevec_lookup_range() now pass
PAGEVEC_SIZE as a desired number of pages.

Just drop the argument.

Link: http://lkml.kernel.org/r/20170726114704.7626-11-jack@suse.cz
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-09-06 17:27:27 -07:00
Jan Kara
2b85a6171d ext4: use pagevec_lookup_range() in writeback code
Both occurences of pagevec_lookup() actually want only pages from a
given range.  Use pagevec_lookup_range() for the lookup.

Link: http://lkml.kernel.org/r/20170726114704.7626-7-jack@suse.cz
Signed-off-by: Jan Kara <jack@suse.cz>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-09-06 17:27:27 -07:00
Jan Kara
dec0da7b60 ext4: use pagevec_lookup_range() in ext4_find_unwritten_pgoff()
Use pagevec_lookup_range() in ext4_find_unwritten_pgoff() since we are
interested only in pages in the given range.  Simplify the logic as a
result of not getting pages out of range and index getting automatically
advanced.

Link: http://lkml.kernel.org/r/20170726114704.7626-6-jack@suse.cz
Signed-off-by: Jan Kara <jack@suse.cz>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-09-06 17:27:26 -07:00
Jan Kara
d72dc8a25a mm: make pagevec_lookup() update index
Make pagevec_lookup() (and underlying find_get_pages()) update index to
the next page where iteration should continue.  Most callers want this
and also pagevec_lookup_tag() already does this.

Link: http://lkml.kernel.org/r/20170726114704.7626-3-jack@suse.cz
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-09-06 17:27:26 -07:00
Ross Zwisler
91d25ba8a6 dax: use common 4k zero page for dax mmap reads
When servicing mmap() reads from file holes the current DAX code
allocates a page cache page of all zeroes and places the struct page
pointer in the mapping->page_tree radix tree.

This has three major drawbacks:

1) It consumes memory unnecessarily. For every 4k page that is read via
   a DAX mmap() over a hole, we allocate a new page cache page. This
   means that if you read 1GiB worth of pages, you end up using 1GiB of
   zeroed memory. This is easily visible by looking at the overall
   memory consumption of the system or by looking at /proc/[pid]/smaps:

	7f62e72b3000-7f63272b3000 rw-s 00000000 103:00 12   /root/dax/data
	Size:            1048576 kB
	Rss:             1048576 kB
	Pss:             1048576 kB
	Shared_Clean:          0 kB
	Shared_Dirty:          0 kB
	Private_Clean:   1048576 kB
	Private_Dirty:         0 kB
	Referenced:      1048576 kB
	Anonymous:             0 kB
	LazyFree:              0 kB
	AnonHugePages:         0 kB
	ShmemPmdMapped:        0 kB
	Shared_Hugetlb:        0 kB
	Private_Hugetlb:       0 kB
	Swap:                  0 kB
	SwapPss:               0 kB
	KernelPageSize:        4 kB
	MMUPageSize:           4 kB
	Locked:                0 kB

2) It is slower than using a common zero page because each page fault
   has more work to do. Instead of just inserting a common zero page we
   have to allocate a page cache page, zero it, and then insert it. Here
   are the average latencies of dax_load_hole() as measured by ftrace on
   a random test box:

    Old method, using zeroed page cache pages:	3.4 us
    New method, using the common 4k zero page:	0.8 us

   This was the average latency over 1 GiB of sequential reads done by
   this simple fio script:

     [global]
     size=1G
     filename=/root/dax/data
     fallocate=none
     [io]
     rw=read
     ioengine=mmap

3) The fact that we had to check for both DAX exceptional entries and
   for page cache pages in the radix tree made the DAX code more
   complex.

Solve these issues by following the lead of the DAX PMD code and using a
common 4k zero page instead.  As with the PMD code we will now insert a
DAX exceptional entry into the radix tree instead of a struct page
pointer which allows us to remove all the special casing in the DAX
code.

Note that we do still pretty aggressively check for regular pages in the
DAX radix tree, especially where we take action based on the bits set in
the page.  If we ever find a regular page in our radix tree now that
most likely means that someone besides DAX is inserting pages (which has
happened lots of times in the past), and we want to find that out early
and fail loudly.

This solution also removes the extra memory consumption.  Here is that
same /proc/[pid]/smaps after 1GiB of reading from a hole with the new
code:

	7f2054a74000-7f2094a74000 rw-s 00000000 103:00 12   /root/dax/data
	Size:            1048576 kB
	Rss:                   0 kB
	Pss:                   0 kB
	Shared_Clean:          0 kB
	Shared_Dirty:          0 kB
	Private_Clean:         0 kB
	Private_Dirty:         0 kB
	Referenced:            0 kB
	Anonymous:             0 kB
	LazyFree:              0 kB
	AnonHugePages:         0 kB
	ShmemPmdMapped:        0 kB
	Shared_Hugetlb:        0 kB
	Private_Hugetlb:       0 kB
	Swap:                  0 kB
	SwapPss:               0 kB
	KernelPageSize:        4 kB
	MMUPageSize:           4 kB
	Locked:                0 kB

Overall system memory consumption is similarly improved.

Another major change is that we remove dax_pfn_mkwrite() from our fault
flow, and instead rely on the page fault itself to make the PTE dirty
and writeable.  The following description from the patch adding the
vm_insert_mixed_mkwrite() call explains this a little more:

   "To be able to use the common 4k zero page in DAX we need to have our
    PTE fault path look more like our PMD fault path where a PTE entry
    can be marked as dirty and writeable as it is first inserted rather
    than waiting for a follow-up dax_pfn_mkwrite() =>
    finish_mkwrite_fault() call.

    Right now we can rely on having a dax_pfn_mkwrite() call because we
    can distinguish between these two cases in do_wp_page():

            case 1: 4k zero page => writable DAX storage
            case 2: read-only DAX storage => writeable DAX storage

    This distinction is made by via vm_normal_page(). vm_normal_page()
    returns false for the common 4k zero page, though, just as it does
    for DAX ptes. Instead of special casing the DAX + 4k zero page case
    we will simplify our DAX PTE page fault sequence so that it matches
    our DAX PMD sequence, and get rid of the dax_pfn_mkwrite() helper.
    We will instead use dax_iomap_fault() to handle write-protection
    faults.

    This means that insert_pfn() needs to follow the lead of
    insert_pfn_pmd() and allow us to pass in a 'mkwrite' flag. If
    'mkwrite' is set insert_pfn() will do the work that was previously
    done by wp_page_reuse() as part of the dax_pfn_mkwrite() call path"

Link: http://lkml.kernel.org/r/20170724170616.25810-4-ross.zwisler@linux.intel.com
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: "Darrick J. Wong" <darrick.wong@oracle.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-09-06 17:27:24 -07:00
Colin Ian King
aed9eb1b21 ext4: fix null pointer dereference on sbi
In the case of a kzalloc failure when allocating sbi we end up
with a null pointer dereference on sbi when assigning sbi->s_daxdev.
Fix this by moving the assignment of sbi->s_daxdev to after the
null pointer check of sbi.

Detected by CoverityScan CID#1455379 ("Dereference before null check")

Fixes: 5e405595e5 ("ext4: perform dax_device lookup at mount")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-09-05 10:02:08 -07:00
Christoph Hellwig
91f9943e1c fs: support RWF_NOWAIT for buffered reads
This is based on the old idea and code from Milosz Tanski.  With the aio
nowait code it becomes mostly trivial now.  Buffered writes continue to
return -EOPNOTSUPP if RWF_NOWAIT is passed.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-09-04 19:04:23 -04:00
Dan Williams
5e405595e5 ext4: perform dax_device lookup at mount
The ->iomap_begin() operation is a hot path, so cache the
fs_dax_get_by_host() result at mount time to avoid the incurring the
hash lookup overhead on a per-i/o basis.

Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Reviewed-by: Jan Kara <jack@suse.cz>
Reported-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-08-31 11:12:13 -07:00
Andreas Dilger
b5f515735b ext4: avoid Y2038 overflow in recently_deleted()
Avoid a 32-bit time overflow in recently_deleted() since i_dtime
(inode deletion time) is stored only as a 32-bit value on disk.
Since i_dtime isn't used for much beyond a boolean value in e2fsck
and is otherwise only used in this function in the kernel, there is
no benefit to use more space in the inode for this field on disk.

Instead, compare only the relative deletion time with the low
32 bits of the time using the newly-added time_before32() helper,
which is similar to time_before() and time_after() for jiffies.

Increase RECENTCY_DIRTY to 300s based on Ted's comments about
usage experience at Google.

Signed-off-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
2017-08-31 11:09:45 -04:00
Randy Dodgen
fd96b8da68 ext4: fix fault handling when mounted with -o dax,ro
If an ext4 filesystem is mounted with both the DAX and read-only
options, executables on that filesystem will fail to start (claiming
'Segmentation fault') due to the fault handler returning
VM_FAULT_SIGBUS.

This is due to the DAX fault handler (see ext4_dax_huge_fault)
attempting to write to the journal when FAULT_FLAG_WRITE is set. This is
the wrong behavior for write faults which will lead to a COW page; in
particular, this fails for readonly mounts.

This change avoids journal writes for faults that are expected to COW.

It might be the case that this could be better handled in
ext4_iomap_begin / ext4_iomap_end (called via iomap_ops inside
dax_iomap_fault). These is some overlap already (e.g. grabbing journal
handles).

Signed-off-by: Randy Dodgen <dodgen@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com>
2017-08-24 15:26:01 -04:00
zhangyi (F)
95f1fda47c ext4: fix quota inconsistency during orphan cleanup for read-only mounts
Quota does not get enabled for read-only mounts if filesystem
has quota feature, so that quotas cannot updated during orphan
cleanup, which will lead to quota inconsistency.

This patch turn on quotas during orphan cleanup for this case,
make sure quotas can be updated correctly.

Reported-by: Jan Kara <jack@suse.cz>
Signed-off-by: zhangyi (F) <yi.zhang@huawei.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: stable@vger.kernel.org # 3.18+
2017-08-24 15:21:50 -04:00
zhangyi (F)
b0a5a9589d ext4: fix incorrect quotaoff if the quota feature is enabled
Current ext4 quota should always "usage enabled" if the
quota feautre is enabled. But in ext4_orphan_cleanup(), it
turn quotas off directly (used for the older journaled
quota), so we cannot turn it on again via "quotaon" unless
umount and remount ext4.

Simple reproduce:

  mkfs.ext4 -O project,quota /dev/vdb1
  mount -o prjquota /dev/vdb1 /mnt
  chattr -p 123 /mnt
  chattr +P /mnt
  touch /mnt/aa /mnt/bb
  exec 100<>/mnt/aa
  rm -f /mnt/aa
  sync
  echo c > /proc/sysrq-trigger

  #reboot and mount
  mount -o prjquota /dev/vdb1 /mnt
  #query status
  quotaon -Ppv /dev/vdb1
  #output
  quotaon: Cannot find mountpoint for device /dev/vdb1
  quotaon: No correct mountpoint specified.

This patch add check for journaled quotas to avoid incorrect
quotaoff when ext4 has quota feautre.

Signed-off-by: zhangyi (F) <yi.zhang@huawei.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: stable@vger.kernel.org # 3.18
2017-08-24 15:19:39 -04:00
Damien Guibouret
918dc9d0ab ext4: remove useless test and assignment in strtohash functions
On transformation of str to hash, computed value is initialised before
first byte modulo 4. But it is already initialised before entering loop
and after processing last byte modulo 4. So the corresponding test and
initialisation could be removed.

Signed-off-by: Damien Guibouret <damien.guibouret@partition-saving.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-08-24 15:11:34 -04:00
Tahsin Erdogan
a6d0567604 ext4: backward compatibility support for Lustre ea_inode implementation
Original Lustre ea_inode feature did not have ref counts on xattr inodes
because there was always one parent that referenced it. New
implementation expects ref count to be initialized which is not true for
Lustre case. Handle this by detecting Lustre created xattr inode and set
its ref count to 1.

The quota handling of xattr inodes have also changed with deduplication
support. New implementation manually manages quotas to support sharing
across multiple users. A consequence is that, a referencing inode
incorporates the blocks of xattr inode into its own i_block field.

We need to know how a xattr inode was created so that we can reverse the
block charges during reference removal. This is handled by introducing a
EXT4_STATE_LUSTRE_EA_INODE flag. The flag is set on a xattr inode if
inode appears to have been created by Lustre. During xattr inode reference
removal, the manual quota uncharge is skipped if the flag is set.

Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-08-24 14:25:02 -04:00
Christoph Hellwig
eaa093d2c0 ext4: remove timebomb in ext4_decode_extra_time()
Changing behavior based on the version code is a timebomb waiting to
happen, and not easily bisectable.  Drop it and leave any removal
to explicit developer action. (And I don't think file system
should _ever_ remove backwards compatibility that has no explicit
flag, but I'll leave that to the ext4 folks).

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Eric Biggers <ebiggers@google.com>
2017-08-24 13:59:24 -04:00
Markus Elfring
d695a1bea3 ext4: use sizeof(*ptr)
Replace the specification of data structures by pointer dereferences
as the parameter for the operator "sizeof" to make the corresponding size
determination a bit safer according to the Linux coding style convention.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
2017-08-24 13:50:24 -04:00
Darrick J. Wong
1bd8d6cd3e ext4: in ext4_seek_{hole,data}, return -ENXIO for negative offsets
In the ext4 implementations of SEEK_HOLE and SEEK_DATA, make sure we
return -ENXIO for negative offsets instead of banging around inside
the extent code and returning -EFSCORRUPTED.

Reported-by: Mateusz S <muttdini@gmail.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org # 4.6
2017-08-24 13:22:06 -04:00
Wang Shilong
901ed070df ext4: reduce lock contention in __ext4_new_inode
While running number of creating file threads concurrently,
we found heavy lock contention on group spinlock:

FUNC                           TOTAL_TIME(us)       COUNT        AVG(us)
ext4_create                    1707443399           1440000      1185.72
_raw_spin_lock                 1317641501           180899929    7.28
jbd2__journal_start            287821030            1453950      197.96
jbd2_journal_get_write_access  33441470             73077185     0.46
ext4_add_nondir                29435963             1440000      20.44
ext4_add_entry                 26015166             1440049      18.07
ext4_dx_add_entry              25729337             1432814      17.96
ext4_mark_inode_dirty          12302433             5774407      2.13

most of cpu time blames to _raw_spin_lock, here is some testing
numbers with/without patch.

Test environment:
Server : SuperMicro Sever (2 x E5-2690 v3@2.60GHz, 128GB 2133MHz
         DDR4 Memory, 8GbFC)
Storage : 2 x RAID1 (DDN SFA7700X, 4 x Toshiba PX02SMU020 200GB
          Read Intensive SSD)

format command:
        mkfs.ext4 -J size=4096

test command:
        mpirun -np 48 mdtest -n 30000 -d /ext4/mdtest.out -F -C \
                -r -i 1 -v -p 10 -u #first run to load inode

        mpirun -np 48 mdtest -n 30000 -d /ext4/mdtest.out -F -C \
                -r -i 3 -v -p 10 -u

Kernel version: 4.13.0-rc3

Test  1,440,000 files with 48 directories by 48 processes:

Without patch:

File Creation   File removal
79,033          289,569 ops/per second
81,463          285,359
79,875          288,475

With patch:
File Creation   File removal
810669		301694
812805		302711
813965		297670

Creation performance is improved more than 10X with large
journal size. The main problem here is we test bitmap
and do some check and journal operations which could be
slept, then we test and set with lock hold, this could
be racy, and make 'inode' steal by other process.

However, after first try, we could confirm handle has
been started and inode bitmap journaled too, then
we could find and set bit with lock hold directly, this
will mostly gurateee success with second try.

Tested-by: Shuichi Ihara <sihara@ddn.com>
Signed-off-by: Wang Shilong <wshilong@ddn.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
2017-08-24 12:56:35 -04:00
Wang Shilong
2fe435d8b0 ext4: cleanup goto next group
avoid duplicated codes, also we need goto
next group in case we found reserved inode.

Signed-off-by: Wang Shilong <wshilong@ddn.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
2017-08-24 11:58:18 -04:00
Jan Kara
4f9d956d19 ext4: do not unnecessarily allocate buffer in recently_deleted()
In recently_deleted() function we want to check whether inode is still
cached in buffer cache. Use sb_find_get_block() for that instead of
sb_getblk() to avoid unnecessary allocation of bdev page and buffer
heads.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-08-24 11:52:21 -04:00
Christoph Hellwig
74d46992e0 block: replace bi_bdev with a gendisk pointer and partitions index
This way we don't need a block_device structure to submit I/O.  The
block_device has different life time rules from the gendisk and
request_queue and is usually only available when the block device node
is open.  Other callers need to explicitly create one (e.g. the lightnvm
passthrough code, or the new nvme multipathing code).

For the actual I/O path all that we need is the gendisk, which exists
once per block device.  But given that the block layer also does
partition remapping we additionally need a partition index, which is
used for said remapping in generic_make_request.

Note that all the block drivers generally want request_queue or
sometimes the gendisk, so this removes a layer of indirection all
over the stack.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-23 12:49:55 -06:00
Jan Kara
7b9ca4c61b quota: Reduce contention on dq_data_lock
dq_data_lock is currently used to protect all modifications of quota
accounting information, consistency of quota accounting on the inode,
and dquot pointers from inode. As a result contention on the lock can be
pretty heavy.

Reduce the contention on the lock by protecting quota accounting
information by a new dquot->dq_dqb_lock and consistency of quota
accounting with inode usage by inode->i_lock.

This change reduces time to create 500000 files on ext4 on ramdisk by 50
different processes in separate directories by 6% when user quota is
turned on. When those 50 processes belong to 50 different users, the
improvement is about 9%.

Signed-off-by: Jan Kara <jack@suse.cz>
2017-08-17 22:07:59 +02:00
Jan Kara
91389240a2 ext4: Disable dirty list tracking of dquots when journalling quotas
When journalling quotas, we writeback all dquots immediately after
changing them as part of current transation. Thus there's no need to
write anything in dquot_writeback_dquots() and so we can avoid updating
list of dirty dquots to reduce dq_list_lock contention.

This change reduces time to create 500000 files on ext4 on ramdisk by 50
different processes in separate directories by 15% when user quota is
turned on.

Signed-off-by: Jan Kara <jack@suse.cz>
2017-08-17 22:00:54 +02:00
Jan Kara
bc8230ee8e quota: Convert dqio_mutex to rwsem
Convert dqio_mutex to rwsem and call it dqio_sem. No functional changes
yet.

Signed-off-by: Jan Kara <jack@suse.cz>
2017-08-17 18:52:48 +02:00
Tahsin Erdogan
32aaf19420 ext4: add missing xattr hash update
When updating an extended attribute, if the padded value sizes are the
same, a shortcut is taken to avoid the bulk of the work. This was fine
until the xattr hash update was moved inside ext4_xattr_set_entry().
With that change, the hash update got missed in the shortcut case.

Thanks to ZhangYi (yizhang089@gmail.com) for root causing the problem.

Fixes: daf8328172 ("ext4: eliminate xattr entry e_hash recalculation for removes")

Reported-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-08-14 08:30:06 -04:00
Theodore Ts'o
b80b32b6d5 ext4: fix clang build regression
Arnd Bergmann <arnd@arndb.de>

As Stefan pointed out, I misremembered what clang can do specifically,
and it turns out that the variable-length array at the end of the
structure did not work (a flexible array would have worked here
but not solved the problem):

fs/ext4/mballoc.c:2303:17: error: fields must have a constant size:
'variable length array in structure' extension will never be supported
                ext4_grpblk_t counters[blocksize_bits + 2];

This reverts part of my previous patch, using a fixed-size array
again, but keeping the check for the array overflow.

Fixes: 2df2c3402f ("ext4: fix warning about stack corruption")
Reported-by: Stefan Agner <stefan@agner.ch>
Tested-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-08-14 08:29:18 -04:00
Maninder Singh
4e56201321 ext4: fix copy paste error in ext4_swap_extents()
This bug was found by a static code checker tool for copy paste
problems.

Signed-off-by: Maninder Singh <maninder1.s@samsung.com>
Signed-off-by: Vaneet Narang <v.narang@samsung.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-08-06 01:33:07 -04:00
Jerry Lee
aec51758ce ext4: fix overflow caused by missing cast in ext4_resize_fs()
On a 32-bit platform, the value of n_blcoks_count may be wrong during
the file system is resized to size larger than 2^32 blocks.  This may
caused the superblock being corrupted with zero blocks count.

Fixes: 1c6bd7173d
Signed-off-by: Jerry Lee <jerrylee@qnap.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org # 3.7+
2017-08-06 01:18:31 -04:00
Miao Xie
c03b45b853 ext4, project: expand inode extra size if possible
When upgrading from old format, try to set project id
to old file first time, it will return EOVERFLOW, but if
that file is dirtied(touch etc), changing project id will
be allowed, this might be confusing for users, we could
try to expand @i_extra_isize here too.

Reported-by: Zhang Yi <yi.zhang@huawei.com>
Signed-off-by: Miao Xie <miaoxie@huawei.com>
Signed-off-by: Wang Shilong <wshilong@ddn.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-08-06 01:00:49 -04:00
Miao Xie
b640b2c51b ext4: cleanup ext4_expand_extra_isize_ea()
Clean up some goto statement, make ext4_expand_extra_isize_ea() clearer.

Signed-off-by: Miao Xie <miaoxie@huawei.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Wang Shilong <wshilong@ddn.com>
2017-08-06 00:55:48 -04:00
Miao Xie
cf0a5e818f ext4: restructure ext4_expand_extra_isize
Current ext4_expand_extra_isize just tries to expand extra isize, if
someone is holding xattr lock or some check fails, it will give up.
So rename its name to ext4_try_to_expand_extra_isize.

Besides that, we clean up unnecessary check and move some relative checks
into it.

Signed-off-by: Miao Xie <miaoxie@huawei.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Wang Shilong <wshilong@ddn.com>
2017-08-06 00:40:01 -04:00
Miao Xie
3b10fdc6d8 ext4: fix forgetten xattr lock protection in ext4_expand_extra_isize
We should avoid the contention between the i_extra_isize update and
the inline data insertion, so move the xattr trylock in front of
i_extra_isize update.

Signed-off-by: Miao Xie <miaoxie@huawei.com>
Reviewed-by: Wang Shilong <wshilong@ddn.com>
2017-08-06 00:27:38 -04:00
Tahsin Erdogan
9699d4f91d ext4: make xattr inode reads faster
ext4_xattr_inode_read() currently reads each block sequentially while
waiting for io operation to complete before moving on to the next
block. This prevents request merging in block layer.

Add a ext4_bread_batch() function that starts reads for all blocks
then optionally waits for them to complete. A similar logic is used
in ext4_find_entry(), so update that code to use the new function.

Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-08-06 00:07:01 -04:00
Tahsin Erdogan
ec00022030 ext4: inplace xattr block update fails to deduplicate blocks
When an xattr block has a single reference, block is updated inplace
and it is reinserted to the cache. Later, a cache lookup is performed
to see whether an existing block has the same contents. This cache
lookup will most of the time return the just inserted entry so
deduplication is not achieved.

Running the following test script will produce two xattr blocks which
can be observed in "File ACL: " line of debugfs output:

  mke2fs -b 1024 -I 128 -F -O extent /dev/sdb 1G
  mount /dev/sdb /mnt/sdb

  touch /mnt/sdb/{x,y}

  setfattr -n user.1 -v aaa /mnt/sdb/x
  setfattr -n user.2 -v bbb /mnt/sdb/x

  setfattr -n user.1 -v aaa /mnt/sdb/y
  setfattr -n user.2 -v bbb /mnt/sdb/y

  debugfs -R 'stat x' /dev/sdb | cat
  debugfs -R 'stat y' /dev/sdb | cat

This patch defers the reinsertion to the cache so that we can locate
other blocks with the same contents.

Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
2017-08-05 22:41:42 -04:00
Tahsin Erdogan
77a2e84d51 ext4: remove unused mode parameter
ext4_alloc_file_blocks() does not use its mode parameter. Remove it.

Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-08-05 22:15:45 -04:00
Arnd Bergmann
2df2c3402f ext4: fix warning about stack corruption
After commit 62d1034f53e3 ("fortify: use WARN instead of BUG for now"),
we get a warning about possible stack overflow from a memcpy that
was not strictly bounded to the size of the local variable:

    inlined from 'ext4_mb_seq_groups_show' at fs/ext4/mballoc.c:2322:2:
include/linux/string.h:309:9: error: '__builtin_memcpy': writing between 161 and 1116 bytes into a region of size 160 overflows the destination [-Werror=stringop-overflow=]

We actually had a bug here that would have been found by the warning,
but it was already fixed last year in commit 30a9d7afe7 ("ext4: fix
stack memory corruption with 64k block size").

This replaces the fixed-length structure on the stack with a variable-length
structure, using the correct upper bound that tells the compiler that
everything is really fine here. I also change the loop count to check
for the same upper bound for consistency, but the existing code is
already correct here.

Note that while clang won't allow certain kinds of variable-length arrays
in structures, this particular instance is fine, as the array is at the
end of the structure, and the size is strictly bounded.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-08-05 21:57:46 -04:00
Andreas Dilger
c741489206 ext4: fix dir_nlink behaviour
The dir_nlink feature has been enabled by default for new ext4
filesystems since e2fsprogs-1.41 in 2008, and was automatically
enabled by the kernel for older ext4 filesystems since the
dir_nlink feature was added with ext4 in kernel 2.6.28+ when
the subdirectory count exceeded EXT4_LINK_MAX-1.

Automatically adding the file system features such as dir_nlink is
generally frowned upon, since it could cause the file system to not be
mountable on older kernel, thus preventing the administrator from
rolling back to an older kernel if necessary.

In this case, the administrator might also want to disable the feature
because glibc's fts_read() function does not correctly optimize
directory traversal for directories that use st_nlinks field of 1 to
indicate that the number of links in the directory are not tracked by
the file system, and could fail to traverse the full directory
hierarchy.  Fortunately, in the past ten years very few users have
complained about incomplete file system traversal by glibc's
fts_read().

This commit also changes ext4_inc_count() to allow i_nlinks to reach
the full EXT4_LINK_MAX links on the parent directory (including "."
and "..") before changing i_links_count to be 1.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=196405
Signed-off-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-08-05 19:47:34 -04:00
Dan Carpenter
381cebfe72 ext4: silence array overflow warning
I get a static checker warning:

    fs/ext4/ext4.h:3091 ext4_set_de_type()
    error: buffer overflow 'ext4_type_by_mode' 15 <= 15

It seems unlikely that we would hit this read overflow in real life, but
it's also simple enough to make the array 16 bytes instead of 15.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-08-05 19:00:31 -04:00
Jan Kara
fcf5ea1099 ext4: fix SEEK_HOLE/SEEK_DATA for blocksize < pagesize
ext4_find_unwritten_pgoff() does not properly handle a situation when
starting index is in the middle of a page and blocksize < pagesize. The
following command shows the bug on filesystem with 1k blocksize:

  xfs_io -f -c "falloc 0 4k" \
            -c "pwrite 1k 1k" \
            -c "pwrite 3k 1k" \
            -c "seek -a -r 0" foo

In this example, neither lseek(fd, 1024, SEEK_HOLE) nor lseek(fd, 2048,
SEEK_DATA) will return the correct result.

Fix the problem by neglecting buffers in a page before starting offset.

Reported-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Jan Kara <jack@suse.cz>
CC: stable@vger.kernel.org # 3.8+
2017-08-05 17:43:24 -04:00
Daeho Jeong
e45105772d ext4: release discard bio after sending discard commands
We've changed the discard command handling into parallel manner.
But, in this change, I forgot decreasing the usage count of the bio
which was used to send discard request. I'm sorry about that.

Fixes: a015434480 ("ext4: send parallel discards on commit completions")
Signed-off-by: Daeho Jeong <daeho.jeong@samsung.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
2017-08-05 13:11:57 -04:00
Jeff Layton
9c5d58fb9e ext4: convert swap_inode_data() over to use swap() on most of the fields
For some odd reason, it forces a byte-by-byte copy of each field. A
plain old swap() on most of these fields would be more efficient. We
do need to retain the memswap of i_data however as that field is an array.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
2017-07-31 00:55:34 -04:00
Emoly Liu
191eac3300 ext4: error should be cleared if ea_inode isn't added to the cache
For Lustre, if ea_inode fails in hash validation but passes parent
inode and generation checks, it won't be added to the cache as well
as the error "-EFSCORRUPTED" should be cleared, otherwise it will
cause "Structure needs cleaning" when running getfattr command.

Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-9723

Cc: stable@vger.kernel.org
Fixes: dec214d00e
Signed-off-by: Emoly Liu <emoly.liu@intel.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Reviewed-by: tahsin@google.com
2017-07-31 00:40:22 -04:00
Jan Kara
a3bb2d5587 ext4: Don't clear SGID when inheriting ACLs
When new directory 'DIR1' is created in a directory 'DIR0' with SGID bit
set, DIR1 is expected to have SGID bit set (and owning group equal to
the owning group of 'DIR0'). However when 'DIR0' also has some default
ACLs that 'DIR1' inherits, setting these ACLs will result in SGID bit on
'DIR1' to get cleared if user is not member of the owning group.

Fix the problem by moving posix_acl_update_mode() out of
__ext4_set_acl() into ext4_set_acl(). That way the function will not be
called when inheriting ACLs which is what we want as it prevents SGID
bit clearing and the mode has been properly set by posix_acl_create()
anyway.

Fixes: 073931017b
CC: stable@vger.kernel.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>
2017-07-30 23:33:01 -04:00
Ernesto A. Fernández
397e434176 ext4: preserve i_mode if __ext4_set_acl() fails
When changing a file's acl mask, __ext4_set_acl() will first set the group
bits of i_mode to the value of the mask, and only then set the actual
extended attribute representing the new acl.

If the second part fails (due to lack of space, for example) and the file
had no acl attribute to begin with, the system will from now on assume
that the mask permission bits are actual group permission bits, potentially
granting access to the wrong users.

Prevent this by only changing the inode mode after the acl has been set.

Signed-off-by: Ernesto A. Fernández <ernesto.mnd.fernandez@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
2017-07-30 22:43:41 -04:00
Eric Whitney
a627b0a7c1 ext4: remove unused metadata accounting variables
Two variables in ext4_inode_info, i_reserved_meta_blocks and
i_allocated_meta_blocks, are unused.  Removing them saves a little
memory per in-memory inode and cleans up clutter in several tracepoints.
Adjust tracepoint output from ext4_alloc_da_blocks() for consistency
and fix a typo and whitespace near these changes.

Signed-off-by: Eric Whitney <enwlinux@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
2017-07-30 22:30:11 -04:00
Eric Whitney
1e21196c8e ext4: correct comment references to ext4_ext_direct_IO()
Commit 914f82a32d "ext4: refactor direct IO code" deleted
ext4_ext_direct_IO(), but references to that function remain in
comments.  Update them to refer to ext4_direct_IO_write().

Signed-off-by: Eric Whitney <enwlinux@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Reviewed-by: Jan Kara <jack@suse.cz>
2017-07-30 22:26:40 -04:00
David Howells
bc98a42c1f VFS: Convert sb->s_flags & MS_RDONLY to sb_rdonly(sb)
Firstly by applying the following with coccinelle's spatch:

	@@ expression SB; @@
	-SB->s_flags & MS_RDONLY
	+sb_rdonly(SB)

to effect the conversion to sb_rdonly(sb), then by applying:

	@@ expression A, SB; @@
	(
	-(!sb_rdonly(SB)) && A
	+!sb_rdonly(SB) && A
	|
	-A != (sb_rdonly(SB))
	+A != sb_rdonly(SB)
	|
	-A == (sb_rdonly(SB))
	+A == sb_rdonly(SB)
	|
	-!(sb_rdonly(SB))
	+!sb_rdonly(SB)
	|
	-A && (sb_rdonly(SB))
	+A && sb_rdonly(SB)
	|
	-A || (sb_rdonly(SB))
	+A || sb_rdonly(SB)
	|
	-(sb_rdonly(SB)) != A
	+sb_rdonly(SB) != A
	|
	-(sb_rdonly(SB)) == A
	+sb_rdonly(SB) == A
	|
	-(sb_rdonly(SB)) && A
	+sb_rdonly(SB) && A
	|
	-(sb_rdonly(SB)) || A
	+sb_rdonly(SB) || A
	)

	@@ expression A, B, SB; @@
	(
	-(sb_rdonly(SB)) ? 1 : 0
	+sb_rdonly(SB)
	|
	-(sb_rdonly(SB)) ? A : B
	+sb_rdonly(SB) ? A : B
	)

to remove left over excess bracketage and finally by applying:

	@@ expression A, SB; @@
	(
	-(A & MS_RDONLY) != sb_rdonly(SB)
	+(bool)(A & MS_RDONLY) != sb_rdonly(SB)
	|
	-(A & MS_RDONLY) == sb_rdonly(SB)
	+(bool)(A & MS_RDONLY) == sb_rdonly(SB)
	)

to make comparisons against the result of sb_rdonly() (which is a bool)
work correctly.

Signed-off-by: David Howells <dhowells@redhat.com>
2017-07-17 08:45:34 +01:00
Linus Torvalds
bc2c6421cb The first major feature for ext4 this merge window is the largedir
feature, which allows ext4 directories to support over 2 billion
 directory entries (assuming ~64 byte file names; in practice, users
 will run into practical performance limits first.)  This feature was
 originally written by the Lustre team, and credit goes to Artem
 Blagodarenko from Seagate for getting this feature upstream.
 
 The second major major feature allows ext4 to support extended
 attribute values up to 64k.  This feature was also originally from
 Lustre, and has been enhanced by Tahsin Erdogan from Google with a
 deduplication feature so that if multiple files have the same xattr
 value (for example, Windows ACL's stored by Samba), only one copy will
 be stored on disk for encoding and caching efficiency.
 
 We also have the usual set of bug fixes, cleanups, and optimizations.
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Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

Pull ext4 updates from Ted Ts'o:
 "The first major feature for ext4 this merge window is the largedir
  feature, which allows ext4 directories to support over 2 billion
  directory entries (assuming ~64 byte file names; in practice, users
  will run into practical performance limits first.) This feature was
  originally written by the Lustre team, and credit goes to Artem
  Blagodarenko from Seagate for getting this feature upstream.

  The second major major feature allows ext4 to support extended
  attribute values up to 64k. This feature was also originally from
  Lustre, and has been enhanced by Tahsin Erdogan from Google with a
  deduplication feature so that if multiple files have the same xattr
  value (for example, Windows ACL's stored by Samba), only one copy will
  be stored on disk for encoding and caching efficiency.

  We also have the usual set of bug fixes, cleanups, and optimizations"

* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (47 commits)
  ext4: fix spelling mistake: "prellocated" -> "preallocated"
  ext4: fix __ext4_new_inode() journal credits calculation
  ext4: skip ext4_init_security() and encryption on ea_inodes
  fs: generic_block_bmap(): initialize all of the fields in the temp bh
  ext4: change fast symlink test to not rely on i_blocks
  ext4: require key for truncate(2) of encrypted file
  ext4: don't bother checking for encryption key in ->mmap()
  ext4: check return value of kstrtoull correctly in reserved_clusters_store
  ext4: fix off-by-one fsmap error on 1k block filesystems
  ext4: return EFSBADCRC if a bad checksum error is found in ext4_find_entry()
  ext4: return EIO on read error in ext4_find_entry
  ext4: forbid encrypting root directory
  ext4: send parallel discards on commit completions
  ext4: avoid unnecessary stalls in ext4_evict_inode()
  ext4: add nombcache mount option
  ext4: strong binding of xattr inode references
  ext4: eliminate xattr entry e_hash recalculation for removes
  ext4: reserve space for xattr entries/names
  quota: add get_inode_usage callback to transfer multi-inode charges
  ext4: xattr inode deduplication
  ...
2017-07-09 09:31:22 -07:00
Linus Torvalds
58f587cb0b Add support for 128-bit AES and some cleanups to fscrypt
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Merge tag 'fscrypt_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/fscrypt

Pull fscrypt updates from Ted Ts'o:
 "Add support for 128-bit AES and some cleanups to fscrypt"

* tag 'fscrypt_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/fscrypt:
  fscrypt: make ->dummy_context() return bool
  fscrypt: add support for AES-128-CBC
  fscrypt: inline fscrypt_free_filename()
2017-07-09 09:03:31 -07:00
Linus Torvalds
088737f44b Writeback error handling fixes (pile #2)
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Merge tag 'for-linus-v4.13-2' of git://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux

Pull Writeback error handling updates from Jeff Layton:
 "This pile represents the bulk of the writeback error handling fixes
  that I have for this cycle. Some of the earlier patches in this pile
  may look trivial but they are prerequisites for later patches in the
  series.

  The aim of this set is to improve how we track and report writeback
  errors to userland. Most applications that care about data integrity
  will periodically call fsync/fdatasync/msync to ensure that their
  writes have made it to the backing store.

  For a very long time, we have tracked writeback errors using two flags
  in the address_space: AS_EIO and AS_ENOSPC. Those flags are set when a
  writeback error occurs (via mapping_set_error) and are cleared as a
  side-effect of filemap_check_errors (as you noted yesterday). This
  model really sucks for userland.

  Only the first task to call fsync (or msync or fdatasync) will see the
  error. Any subsequent task calling fsync on a file will get back 0
  (unless another writeback error occurs in the interim). If I have
  several tasks writing to a file and calling fsync to ensure that their
  writes got stored, then I need to have them coordinate with one
  another. That's difficult enough, but in a world of containerized
  setups that coordination may even not be possible.

  But wait...it gets worse!

  The calls to filemap_check_errors can be buried pretty far down in the
  call stack, and there are internal callers of filemap_write_and_wait
  and the like that also end up clearing those errors. Many of those
  callers ignore the error return from that function or return it to
  userland at nonsensical times (e.g. truncate() or stat()). If I get
  back -EIO on a truncate, there is no reason to think that it was
  because some previous writeback failed, and a subsequent fsync() will
  (incorrectly) return 0.

  This pile aims to do three things:

   1) ensure that when a writeback error occurs that that error will be
      reported to userland on a subsequent fsync/fdatasync/msync call,
      regardless of what internal callers are doing

   2) report writeback errors on all file descriptions that were open at
      the time that the error occurred. This is a user-visible change,
      but I think most applications are written to assume this behavior
      anyway. Those that aren't are unlikely to be hurt by it.

   3) document what filesystems should do when there is a writeback
      error. Today, there is very little consistency between them, and a
      lot of cargo-cult copying. We need to make it very clear what
      filesystems should do in this situation.

  To achieve this, the set adds a new data type (errseq_t) and then
  builds new writeback error tracking infrastructure around that. Once
  all of that is in place, we change the filesystems to use the new
  infrastructure for reporting wb errors to userland.

  Note that this is just the initial foray into cleaning up this mess.
  There is a lot of work remaining here:

   1) convert the rest of the filesystems in a similar fashion. Once the
      initial set is in, then I think most other fs' will be fairly
      simple to convert. Hopefully most of those can in via individual
      filesystem trees.

   2) convert internal waiters on writeback to use errseq_t for
      detecting errors instead of relying on the AS_* flags. I have some
      draft patches for this for ext4, but they are not quite ready for
      prime time yet.

  This was a discussion topic this year at LSF/MM too. If you're
  interested in the gory details, LWN has some good articles about this:

      https://lwn.net/Articles/718734/
      https://lwn.net/Articles/724307/"

* tag 'for-linus-v4.13-2' of git://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux:
  btrfs: minimal conversion to errseq_t writeback error reporting on fsync
  xfs: minimal conversion to errseq_t writeback error reporting
  ext4: use errseq_t based error handling for reporting data writeback errors
  fs: convert __generic_file_fsync to use errseq_t based reporting
  block: convert to errseq_t based writeback error tracking
  dax: set errors in mapping when writeback fails
  Documentation: flesh out the section in vfs.txt on storing and reporting writeback errors
  mm: set both AS_EIO/AS_ENOSPC and errseq_t in mapping_set_error
  fs: new infrastructure for writeback error handling and reporting
  lib: add errseq_t type and infrastructure for handling it
  mm: don't TestClearPageError in __filemap_fdatawait_range
  mm: clear AS_EIO/AS_ENOSPC when writeback initiation fails
  jbd2: don't clear and reset errors after waiting on writeback
  buffer: set errors in mapping at the time that the error occurs
  fs: check for writeback errors after syncing out buffers in generic_file_fsync
  buffer: use mapping_set_error instead of setting the flag
  mm: fix mapping_set_error call in me_pagecache_dirty
2017-07-07 19:38:17 -07:00
Colin Ian King
ff95015648 ext4: fix spelling mistake: "prellocated" -> "preallocated"
Trivial fix to spelling mistake in mb_debug debug message

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-07-06 15:28:45 -04:00
Jeff Layton
6acec592c6 ext4: use errseq_t based error handling for reporting data writeback errors
Add a call to filemap_report_wb_err at the end of ext4_sync_file. This
will ensure that we check and advance the errseq_t in the file, which
allows us to track and report errors on all open fds when they occur.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
2017-07-06 07:02:30 -04:00
Tahsin Erdogan
af65207c76 ext4: fix __ext4_new_inode() journal credits calculation
ea_inode feature allows creating extended attributes that are up to
64k in size. Update __ext4_new_inode() to pick increased credit limits.

To avoid overallocating too many journal credits, update
__ext4_xattr_set_credits() to make a distinction between xattr create
vs update. This helps __ext4_new_inode() because all attributes are
known to be new, so we can save credits that are normally needed to
delete old values.

Also, have fscrypt specify its maximum context size so that we don't
end up allocating credits for 64k size.

Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-07-06 00:01:59 -04:00
Tahsin Erdogan
ad47f95339 ext4: skip ext4_init_security() and encryption on ea_inodes
Extended attribute inodes are internal to ext4. Adding encryption/security
related attributes on them would mean dealing with nested calls into ea code.
Since they have no direct exposure to user mode, just avoid creating ea
entries for them.

Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-07-06 00:00:59 -04:00
Tahsin Erdogan
407cd7fb83 ext4: change fast symlink test to not rely on i_blocks
ext4_inode_info->i_data is the storage area for 4 types of data:

  a) Extents data
  b) Inline data
  c) Block map
  d) Fast symlink data (symlink length < 60)

Extents data case is positively identified by EXT4_INODE_EXTENTS flag.
Inline data case is also obvious because of EXT4_INODE_INLINE_DATA
flag.

Distinguishing c) and d) however requires additional logic. This
currently relies on i_blocks count. After subtracting external xattr
block from i_blocks, if it is greater than 0 then we know that some
data blocks exist, so there must be a block map.

This logic got broken after ea_inode feature was added. That feature
charges the data blocks of external xattr inodes to the referencing
inode and so adds them to the i_blocks. To fix this, we could subtract
ea_inode blocks by iterating through all xattr entries and then check
whether remaining i_blocks count is zero. Besides being complicated,
this won't change the fact that the current way of distinguishing
between c) and d) is fragile.

The alternative solution is to test whether i_size is less than 60 to
determine fast symlink case. ext4_symlink() uses the same test to decide
whether to store the symlink in i_data. There is one caveat to address
before this can work though.

If an inode's i_nlink is zero during eviction, its i_size is set to
zero and its data is truncated. If system crashes before inode is removed
from the orphan list, next boot orphan cleanup may find the inode with
zero i_size. So, a symlink that had its data stored in a block may now
appear to be a fast symlink. The solution used in this patch is to treat
i_size = 0 as a non-fast symlink case. A zero sized symlink is not legal
so the only time this can happen is the mentioned scenario. This is also
logically correct because a i_size = 0 symlink has no data stored in
i_data.

Suggested-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
2017-07-04 00:11:21 -04:00
Jens Axboe
0127251c45 ext4: add support for passing in write hints for buffered writes
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-27 12:05:44 -06:00
Eric Biggers
c250b7dd8e fscrypt: make ->dummy_context() return bool
This makes it consistent with ->is_encrypted(), ->empty_dir(), and
fscrypt_dummy_context_enabled().

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-06-23 20:11:50 -04:00
Eric Biggers
63136858ae ext4: require key for truncate(2) of encrypted file
Currently, filesystems allow truncate(2) on an encrypted file without
the encryption key.  However, it's impossible to correctly handle the
case where the size being truncated to is not a multiple of the
filesystem block size, because that would require decrypting the final
block, zeroing the part beyond i_size, then encrypting the block.

As other modifications to encrypted file contents are prohibited without
the key, just prohibit truncate(2) as well, making it fail with ENOKEY.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-06-23 19:48:44 -04:00
Eric Biggers
66e0aaadce ext4: don't bother checking for encryption key in ->mmap()
Since only an open file can be mmap'ed, and we only allow open()ing an
encrypted file when its key is available, there is no need to check for
the key again before permitting each mmap().

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-06-23 19:41:38 -04:00
Chao Yu
1ea1516fbb ext4: check return value of kstrtoull correctly in reserved_clusters_store
kstrtoull returns 0 on success, however, in reserved_clusters_store we
will return -EINVAL if kstrtoull returns 0, it makes us fail to update
reserved_clusters value through sysfs.

Fixes: 76d33bca55
Cc: stable@vger.kernel.org # 4.4
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Miao Xie <miaoxie@huawei.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-06-23 01:08:22 -04:00
Darrick J. Wong
4a4956249d ext4: fix off-by-one fsmap error on 1k block filesystems
For 1k-block filesystems, the filesystem starts at block 1, not block 0.
This fact is recorded in s_first_data_block, so use that to bump up the
start_fsb before we start querying the filesystem for its space map.
Without this, ext4/026 fails on 1k block ext4 because various functions
(notably ext4_get_group_no_and_offset) don't know what to do with an
fsblock that is "before" the start of the filesystem and return garbage
results (blockgroup 2^32-1, etc.) that confuse fsmap.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-06-23 00:58:57 -04:00
Theodore Ts'o
bdddf34279 ext4: return EFSBADCRC if a bad checksum error is found in ext4_find_entry()
Previously a bad directory block with a bad checksum is skipped; we
should be returning EFSBADCRC (aka EBADMSG).

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-06-23 00:47:05 -04:00
Khazhismel Kumykov
6febe6f253 ext4: return EIO on read error in ext4_find_entry
Previously, a read error would be ignored and we would eventually return
NULL from ext4_find_entry, which signals "no such file or directory". We
should be returning EIO.

Signed-off-by: Khazhismel Kumykov <khazhy@google.com>
2017-06-23 00:29:05 -04:00
Eric Biggers
9ce0151a47 ext4: forbid encrypting root directory
Currently it's possible to encrypt all files and directories on an ext4
filesystem by deleting everything, including lost+found, then setting an
encryption policy on the root directory.  However, this is incompatible
with e2fsck because e2fsck expects to find, create, and/or write to
lost+found and does not have access to any encryption keys.  Especially
problematic is that if e2fsck can't find lost+found, it will create it
without regard for whether the root directory is encrypted.  This is
wrong for obvious reasons, and it causes a later run of e2fsck to
consider the lost+found directory entry to be corrupted.

Encrypting the root directory may also be of limited use because it is
the "all-or-nothing" use case, for which dm-crypt can be used instead.
(By design, encryption policies are inherited and cannot be overridden;
so the root directory having an encryption policy implies that all files
and directories on the filesystem have that same encryption policy.)

In any case, encrypting the root directory is broken currently and must
not be allowed; so start returning an error if userspace requests it.
For now only do this in ext4, because f2fs and ubifs do not appear to
have the lost+found requirement.  We could move it into
fscrypt_ioctl_set_policy() later if desired, though.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
2017-06-23 00:10:36 -04:00
Daeho Jeong
a015434480 ext4: send parallel discards on commit completions
Now, when we mount ext4 filesystem with '-o discard' option, we have to
issue all the discard commands for the blocks to be deallocated and
wait for the completion of the commands on the commit complete phase.
Because this procedure might involve a lot of sequential combinations of
issuing discard commands and waiting for that, the delay of this
procedure might be too much long, even to 17.0s in our test,
and it results in long commit delay and fsync() performance degradation.

To reduce this kind of delay, instead of adding callback for each
extent and handling all of them in a sequential manner on commit phase,
we instead add a separate list of extents to free to the superblock and
then process this list at once after transaction commits so that
we can issue all the discard commands in a parallel manner like XFS
filesystem.

Finally, we could enhance the discard command handling performance.
The result was such that 17.0s delay of a single commit in the worst
case has been enhanced to 4.8s.

Signed-off-by: Daeho Jeong <daeho.jeong@samsung.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Tested-by: Hobin Woo <hobin.woo@samsung.com>
Tested-by: Kitae Lee <kitae87.lee@samsung.com>
Reviewed-by: Jan Kara <jack@suse.cz>
2017-06-22 23:54:33 -04:00
Jan Kara
3abb1a0fc2 ext4: avoid unnecessary stalls in ext4_evict_inode()
These days inode reclaim calls evict_inode() only when it has no pages
in the mapping.  In that case it is not necessary to wait for transaction
commit in ext4_evict_inode() as there can be no pages waiting to be
committed.  So avoid unnecessary transaction waiting in that case.

We still have to keep the check for the case where ext4_evict_inode()
gets called from other paths (e.g. umount) where inode still can have
some page cache pages.

Reported-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-06-22 23:49:46 -04:00
Tahsin Erdogan
cdb7ee4c63 ext4: add nombcache mount option
The main purpose of mb cache is to achieve deduplication in
extended attributes. In use cases where opportunity for deduplication
is unlikely, it only adds overhead.

Add a mount option to explicitly turn off mb cache.

Suggested-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-06-22 11:55:14 -04:00
Tahsin Erdogan
b9fc761ea2 ext4: strong binding of xattr inode references
To verify that a xattr entry is not pointing to the wrong xattr inode,
we currently check that the target inode has EXT4_EA_INODE_FL flag set and
also the entry size matches the target inode size.

For stronger validation, also incorporate crc32c hash of the value into
the e_hash field. This is done regardless of whether the entry lives in
the inode body or external attribute block.

Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-06-22 11:53:15 -04:00
Tahsin Erdogan
daf8328172 ext4: eliminate xattr entry e_hash recalculation for removes
When an extended attribute block is modified, ext4_xattr_hash_entry()
recalculates e_hash for the entry that is pointed by s->here. This  is
unnecessary if the modification is to remove an entry.

Currently, if the removed entry is the last one and there are other
entries remaining, hash calculation targets the just erased entry which
has been filled with zeroes and effectively does nothing.  If the removed
entry is not the last one and there are more entries, this time it will
recalculate hash on the next entry which is totally unnecessary.

Fix these by moving the decision on when to recalculate hash to
ext4_xattr_set_entry().

Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-06-22 11:52:03 -04:00
Tahsin Erdogan
9c6e7853c5 ext4: reserve space for xattr entries/names
New ea_inode feature allows putting large xattr values into external
inodes.  struct ext4_xattr_entry and the attribute name however have to
remain in the inode extra space or external attribute block.  Once that
space is exhausted, no further entries can be added.  Some of that space
could also be used by values that fit in there at the time of addition.

So, a single xattr entry whose value barely fits in the external block
could prevent further entries being added.

To mitigate the problem, this patch introduces a notion of reserved
space in the external attribute block that cannot be used by value data.
This reserve is enforced when ea_inode feature is enabled.  The amount
of reserve is arbitrarily chosen to be min(block_size/8, 1024).  The
table below shows how much space is reserved for each block size and the
guaranteed mininum number of entries that can be placed in the external
attribute block.

block size     reserved bytes  entries (name length = 16)
 1k            128              3
 2k            256              7
 4k            512             15
 8k            1024            31
16k            1024            31
32k            1024            31
64k            1024            31

Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-06-22 11:48:53 -04:00
Tahsin Erdogan
7a9ca53aea quota: add get_inode_usage callback to transfer multi-inode charges
Ext4 ea_inode feature allows storing xattr values in external inodes to
be able to store values that are bigger than a block in size. Ext4 also
has deduplication support for these type of inodes. With deduplication,
the actual storage waste is eliminated but the users of such inodes are
still charged full quota for the inodes as if there was no sharing
happening in the background.

This design requires ext4 to manually charge the users because the
inodes are shared.

An implication of this is that, if someone calls chown on a file that
has such references we need to transfer the quota for the file and xattr
inodes. Current dquot_transfer() function implicitly transfers one inode
charge. With ea_inode feature, we would like to transfer multiple inode
charges.

Add get_inode_usage callback which can interrogate the total number of
inodes that were charged for a given inode.

[ Applied fix from Colin King to make sure the 'ret' variable is
  initialized on the successful return path.  Detected by
  CoverityScan, CID#1446616 ("Uninitialized scalar variable") --tytso]

Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Jan Kara <jack@suse.cz>
2017-06-22 11:46:48 -04:00
Tahsin Erdogan
dec214d00e ext4: xattr inode deduplication
Ext4 now supports xattr values that are up to 64k in size (vfs limit).
Large xattr values are stored in external inodes each one holding a
single value. Once written the data blocks of these inodes are immutable.

The real world use cases are expected to have a lot of value duplication
such as inherited acls etc. To reduce data duplication on disk, this patch
implements a deduplicator that allows sharing of xattr inodes.

The deduplication is based on an in-memory hash lookup that is a best
effort sharing scheme. When a xattr inode is read from disk (i.e.
getxattr() call), its crc32c hash is added to a hash table. Before
creating a new xattr inode for a value being set, the hash table is
checked to see if an existing inode holds an identical value. If such an
inode is found, the ref count on that inode is incremented. On value
removal the ref count is decremented and if it reaches zero the inode is
deleted.

The quota charging for such inodes is manually managed. Every reference
holder is charged the full size as if there was no sharing happening.
This is consistent with how xattr blocks are also charged.

[ Fixed up journal credits calculation to handle inline data and the
  rare case where an shared xattr block can get freed when two thread
  race on breaking the xattr block sharing. --tytso ]

Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-06-22 11:44:55 -04:00
Tahsin Erdogan
30a7eb970c ext4: cleanup transaction restarts during inode deletion
During inode deletion, the number of journal credits that will be
needed is hard to determine.  For that reason we have journal
extend/restart calls in several places.  Whenever a transaction is
restarted, filesystem must be in a consistent state because there is
no atomicity guarantee beyond a restart call.

Add ext4_xattr_ensure_credits() helper function which takes care of
journal extend/restart logic.  It also handles getting jbd2 write
access and dirty metadata calls.  This function is called at every
iteration of handling an ea_inode reference.

Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-06-22 11:42:09 -04:00
Tahsin Erdogan
02749a4c20 ext4: add ext4_is_quota_file()
IS_NOQUOTA() indicates whether quota is disabled for an inode. Ext4
also uses it to check whether an inode is for a quota file. The
distinction currently doesn't matter because quota is disabled only
for the quota files. When we start disabling quota for other inodes
in the future, we will want to make the distinction clear.

Replace IS_NOQUOTA() call with ext4_is_quota_file() at places where
we are checking for quota files.

Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-06-22 11:31:25 -04:00
Tahsin Erdogan
47387409ee ext2, ext4: make mb block cache names more explicit
There will be a second mb_cache instance that tracks ea_inodes. Make
existing names more explicit so that it is clear that they refer to
xattr block cache.

Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-06-22 11:28:55 -04:00
Tahsin Erdogan
c07dfcb458 mbcache: make mbcache naming more generic
Make names more generic so that mbcache usage is not limited to
block sharing. In a subsequent patch in the series
("ext4: xattr inode deduplication"), we start using the mbcache code
for sharing xattr inodes. With that patch, old mb_cache_entry.e_block
field could be holding either a block number or an inode number.

Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-06-22 10:29:53 -04:00
Tahsin Erdogan
b6d9029df0 ext4: move struct ext4_xattr_inode_array to xattr.h
Since this is a xattr specific data structure it is cleaner to keep it in
xattr header file.

Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-06-22 10:28:38 -04:00
Tahsin Erdogan
0421a189bc ext4: modify ext4_xattr_ino_array to hold struct inode *
Tracking struct inode * rather than the inode number eliminates the
repeated ext4_xattr_inode_iget() call later. The second call cannot
fail in practice but still requires explanation when it wants to ignore
the return value. Avoid the trouble and make things simple.

Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-06-22 10:26:31 -04:00
Tahsin Erdogan
c1a5d5f6ab ext4: improve journal credit handling in set xattr paths
Both ext4_set_acl() and ext4_set_context() need to be made aware of
ea_inode feature when it comes to credits calculation.

Also add a sufficient credits check in ext4_xattr_set_handle() right
after xattr write lock is grabbed. Original credits calculation is done
outside the lock so there is a possiblity that the initially calculated
credits are not sufficient anymore.

Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-06-21 22:28:40 -04:00
Tahsin Erdogan
65d3000520 ext4: ext4_xattr_delete_inode() should return accurate errors
In a few places the function returns without trying to pass the actual
error code to the caller. Fix those.

Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-06-21 22:24:38 -04:00
Tahsin Erdogan
b347e2bcd1 ext4: retry storing value in external inode with xattr block too
When value size is <= EXT4_XATTR_MIN_LARGE_EA_SIZE(), and it
doesn't fit in either inline or xattr block, a second try is made to
store it in an external inode while storing the entry itself in inline
area. There should also be an attempt to store the entry in xattr block.

This patch adds a retry loop to do that. It also makes the caller the
sole decider on whether to store a value in an external inode.

Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-06-21 22:20:32 -04:00
Tahsin Erdogan
b315529891 ext4: fix credits calculation for xattr inode
When there is no space for a value in xattr block, it may be stored
in an xattr inode even if the value length is less than
EXT4_XATTR_MIN_LARGE_EA_SIZE(). So the current assumption in credits
calculation is wrong.

Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-06-21 22:16:20 -04:00
Tahsin Erdogan
7cec191894 ext4: fix ext4_xattr_cmp()
When a xattr entry refers to an external inode, the value data is not
available in the inline area so we should not attempt to read it using
value offset.

Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-06-21 22:14:30 -04:00
Tahsin Erdogan
f6109100ba ext4: fix ext4_xattr_move_to_block()
When moving xattr entries from inline area to a xattr block, entries
that refer to external xattr inodes need special handling because
value data is not available in the inline area but rather should be
read from its external inode.

Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-06-21 22:11:54 -04:00
Tahsin Erdogan
9bb21cedda ext4: fix ext4_xattr_make_inode_space() value size calculation
ext4_xattr_make_inode_space() is interested in calculating the inline
space used in an inode. When a xattr entry refers to an external inode
the value size indicates the external inode size, not the value size in
the inline area. Change the function to take this into account.

Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-06-21 22:05:44 -04:00
Tahsin Erdogan
0bd454c04f ext4: ext4_xattr_value_same() should return false for external data
ext4_xattr_value_same() is used as a quick optimization in case the new
xattr value is identical to the previous value. When xattr value is
stored in a xattr inode the check becomes expensive so it is better to
just assume that they are not equal.

Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-06-21 22:02:06 -04:00
Tahsin Erdogan
990461dd85 ext4: add missing le32_to_cpu(e_value_inum) conversions
Two places in code missed converting xattr inode number using
le32_to_cpu().

Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-06-21 21:59:30 -04:00
Tahsin Erdogan
9096669332 ext4: clean up ext4_xattr_inode_get()
The input and output values of *size parameter are equal on successful
return from ext4_xattr_inode_get().  On error return, the callers ignore
the output value so there is no need to update it.

Also check for NULL return from ext4_bread().  If the actual xattr inode
size happens to be smaller than the expected size, ext4_bread() may
return NULL which would indicate data corruption.

Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-06-21 21:57:36 -04:00
Tahsin Erdogan
bab79b0499 ext4: change ext4_xattr_inode_iget() signature
In general, kernel functions indicate success/failure through their return
values. This function returns the status as an output parameter and reserves
the return value for the inode. Make it follow the general convention.

Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-06-21 21:49:53 -04:00
Tahsin Erdogan
0eefb10758 ext4: extended attribute value size limit is enforced by vfs
EXT4_XATTR_MAX_LARGE_EA_SIZE definition in ext4 is currently unused.
Besides, vfs enforces its own 64k limit which makes the 1MB limit in
ext4 redundant. Remove it.

Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-06-21 21:41:37 -04:00
Tahsin Erdogan
1e7d359d71 ext4: fix ref counting for ea_inode
The ref count on ea_inode is incremented by
ext4_xattr_inode_orphan_add() which is supposed to be decremented by
ext4_xattr_inode_array_free(). The decrement is conditioned on whether
the ea_inode is currently on the orphan list. However, the orphan list
addition only happens when journaling is enabled. In non-journaled case,r
we fail to release the ref count causing an error message like below.

"VFS: Busy inodes after unmount of sdb. Self-destruct in 5 seconds.
Have a nice day..."

Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-06-21 21:39:38 -04:00
Tahsin Erdogan
ddfa17e4ad ext4: call journal revoke when freeing ea_inode blocks
ea_inode contents are treated as metadata, that's why it is journaled
during initial writes. Failing to call revoke during freeing could cause
user data to be overwritten with original ea_inode contents during journal
replay.

Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-06-21 21:36:51 -04:00
Tahsin Erdogan
9e1ba00161 ext4: ea_inode owner should be the same as the inode owner
Quota charging is based on the ownership of the inode. Currently, the
xattr inode owner is set to the caller which may be different from the
parent inode owner. This is inconsistent with how quota is charged for
xattr block and regular data block writes.

Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-06-21 21:27:00 -04:00
Tahsin Erdogan
bd3b963b27 ext4: attach jinode after creation of xattr inode
In data=ordered mode jinode needs to be attached to the xattr inode when
writing data to it. Attachment normally occurs during file open for regular
files. Since we are not using file interface to write to the xattr inode,
the jinode attach needs to be done manually.

Otherwise the following crash occurs in data=ordered mode.

 BUG: unable to handle kernel NULL pointer dereference at           (null)
 IP: jbd2_journal_file_inode+0x37/0x110
 PGD 13b3c0067
 P4D 13b3c0067
 PUD 137660067
 PMD 0

 Oops: 0000 [#1] SMP
 CPU: 3 PID: 1877 Comm: python Not tainted 4.12.0-rc1+ #749
 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
 task: ffff88010e368980 task.stack: ffffc90000374000
 RIP: 0010:jbd2_journal_file_inode+0x37/0x110
 RSP: 0018:ffffc90000377980 EFLAGS: 00010246
 RAX: 0000000000000000 RBX: ffff880123b06230 RCX: 0000000000280000
 RDX: 0000000000000006 RSI: 0000000000000000 RDI: ffff88012c8585d0
 RBP: ffffc900003779b0 R08: 0000000000000202 R09: 0000000000000001
 R10: 0000000000000000 R11: 0000000000000400 R12: ffff8801111f81c0
 R13: ffff88013b2b6800 R14: ffffc90000377ab0 R15: 0000000000000001
 FS:  00007f0c99b77740(0000) GS:ffff88013fd80000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 0000000000000000 CR3: 0000000136d91000 CR4: 00000000000006e0
 Call Trace:
  jbd2_journal_inode_add_write+0xe/0x10
  ext4_map_blocks+0x59e/0x620
  ext4_xattr_set_entry+0x501/0x7d0
  ext4_xattr_block_set+0x1b2/0x9b0
  ext4_xattr_set_handle+0x322/0x4f0
  ext4_xattr_set+0x144/0x1a0
  ext4_xattr_user_set+0x34/0x40
  __vfs_setxattr+0x66/0x80
  __vfs_setxattr_noperm+0x69/0x1c0
  vfs_setxattr+0xa2/0xb0
  setxattr+0x12e/0x150
  path_setxattr+0x87/0xb0
  SyS_setxattr+0xf/0x20
  entry_SYSCALL_64_fastpath+0x18/0xad

Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-06-21 21:24:31 -04:00
Tahsin Erdogan
1b917ed8ae ext4: do not set posix acls on xattr inodes
We don't need acls on xattr inodes because they are not directly
accessible from user mode.

Besides lockdep complains about recursive locking of xattr_sem as seen
below.

  =============================================
  [ INFO: possible recursive locking detected ]
  4.11.0-rc8+ #402 Not tainted
  ---------------------------------------------
  python/1894 is trying to acquire lock:
   (&ei->xattr_sem){++++..}, at: [<ffffffff804878a6>] ext4_xattr_get+0x66/0x270

  but task is already holding lock:
   (&ei->xattr_sem){++++..}, at: [<ffffffff80489500>] ext4_xattr_set_handle+0xa0/0x5d0

  other info that might help us debug this:
   Possible unsafe locking scenario:

         CPU0
         ----
    lock(&ei->xattr_sem);
    lock(&ei->xattr_sem);

   *** DEADLOCK ***

   May be due to missing lock nesting notation

  3 locks held by python/1894:
   #0:  (sb_writers#10){.+.+.+}, at: [<ffffffff803d829f>] mnt_want_write+0x1f/0x50
   #1:  (&sb->s_type->i_mutex_key#15){+.+...}, at: [<ffffffff803dda27>] vfs_setxattr+0x57/0xb0
   #2:  (&ei->xattr_sem){++++..}, at: [<ffffffff80489500>] ext4_xattr_set_handle+0xa0/0x5d0

  stack backtrace:
  CPU: 0 PID: 1894 Comm: python Not tainted 4.11.0-rc8+ #402
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
  Call Trace:
   dump_stack+0x67/0x99
   __lock_acquire+0x5f3/0x1830
   lock_acquire+0xb5/0x1d0
   down_read+0x2f/0x60
   ext4_xattr_get+0x66/0x270
   ext4_get_acl+0x43/0x1e0
   get_acl+0x72/0xf0
   posix_acl_create+0x5e/0x170
   ext4_init_acl+0x21/0xc0
   __ext4_new_inode+0xffd/0x16b0
   ext4_xattr_set_entry+0x5ea/0xb70
   ext4_xattr_block_set+0x1b5/0x970
   ext4_xattr_set_handle+0x351/0x5d0
   ext4_xattr_set+0x124/0x180
   ext4_xattr_user_set+0x34/0x40
   __vfs_setxattr+0x66/0x80
   __vfs_setxattr_noperm+0x69/0x1c0
   vfs_setxattr+0xa2/0xb0
   setxattr+0x129/0x160
   path_setxattr+0x87/0xb0
   SyS_setxattr+0xf/0x20
   entry_SYSCALL_64_fastpath+0x18/0xad

Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-06-21 21:21:39 -04:00
Tahsin Erdogan
0de5983d35 ext4: lock inode before calling ext4_orphan_add()
ext4_orphan_add() requires caller to be holding the inode lock.
Add missing lock statements.

 WARNING: CPU: 3 PID: 1806 at fs/ext4/namei.c:2731 ext4_orphan_add+0x4e/0x240
 CPU: 3 PID: 1806 Comm: python Not tainted 4.12.0-rc1+ #746
 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
 task: ffff880135d466c0 task.stack: ffffc900014b0000
 RIP: 0010:ext4_orphan_add+0x4e/0x240
 RSP: 0018:ffffc900014b3d50 EFLAGS: 00010246
 RAX: 0000000000000000 RBX: ffff8801348fe1f0 RCX: ffffc900014b3c64
 RDX: 0000000000000000 RSI: ffff8801348fe1f0 RDI: ffff8801348fe1f0
 RBP: ffffc900014b3da0 R08: 0000000000000000 R09: ffffffff80e82025
 R10: 0000000000004692 R11: 000000000000468d R12: ffff880137598000
 R13: ffff880137217000 R14: ffff880134ac58d0 R15: 0000000000000000
 FS:  00007fc50f09e740(0000) GS:ffff88013fd80000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 00000000008bc2e0 CR3: 00000001375ac000 CR4: 00000000000006e0
 Call Trace:
  ext4_xattr_inode_orphan_add.constprop.19+0x9d/0xf0
  ext4_xattr_delete_inode+0x1c4/0x2f0
  ext4_evict_inode+0x15a/0x7f0
  evict+0xc0/0x1a0
  iput+0x16a/0x270
  do_unlinkat+0x172/0x290
  SyS_unlink+0x11/0x20
  entry_SYSCALL_64_fastpath+0x18/0xad

Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-06-21 21:19:16 -04:00
Tahsin Erdogan
33d201e027 ext4: fix lockdep warning about recursive inode locking
Setting a large xattr value may require writing the attribute contents
to an external inode. In this case we may need to lock the xattr inode
along with the parent inode. This doesn't pose a deadlock risk because
xattr inodes are not directly visible to the user and their access is
restricted.

Assign a lockdep subclass to xattr inode's lock.

 ============================================
 WARNING: possible recursive locking detected
 4.12.0-rc1+ #740 Not tainted
 --------------------------------------------
 python/1822 is trying to acquire lock:
  (&sb->s_type->i_mutex_key#15){+.+...}, at: [<ffffffff804912ca>] ext4_xattr_set_entry+0x65a/0x7b0

 but task is already holding lock:
  (&sb->s_type->i_mutex_key#15){+.+...}, at: [<ffffffff803d6687>] vfs_setxattr+0x57/0xb0

 other info that might help us debug this:
  Possible unsafe locking scenario:

        CPU0
        ----
   lock(&sb->s_type->i_mutex_key#15);
   lock(&sb->s_type->i_mutex_key#15);

  *** DEADLOCK ***

  May be due to missing lock nesting notation

 4 locks held by python/1822:
  #0:  (sb_writers#10){.+.+.+}, at: [<ffffffff803d0eef>] mnt_want_write+0x1f/0x50
  #1:  (&sb->s_type->i_mutex_key#15){+.+...}, at: [<ffffffff803d6687>] vfs_setxattr+0x57/0xb0
  #2:  (jbd2_handle){.+.+..}, at: [<ffffffff80493f40>] start_this_handle+0xf0/0x420
  #3:  (&ei->xattr_sem){++++..}, at: [<ffffffff804920ba>] ext4_xattr_set_handle+0x9a/0x4f0

 stack backtrace:
 CPU: 0 PID: 1822 Comm: python Not tainted 4.12.0-rc1+ #740
 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
 Call Trace:
  dump_stack+0x67/0x9e
  __lock_acquire+0x5f3/0x1750
  lock_acquire+0xb5/0x1d0
  down_write+0x2c/0x60
  ext4_xattr_set_entry+0x65a/0x7b0
  ext4_xattr_block_set+0x1b2/0x9b0
  ext4_xattr_set_handle+0x322/0x4f0
  ext4_xattr_set+0x144/0x1a0
  ext4_xattr_user_set+0x34/0x40
  __vfs_setxattr+0x66/0x80
  __vfs_setxattr_noperm+0x69/0x1c0
  vfs_setxattr+0xa2/0xb0
  setxattr+0x12e/0x150
  path_setxattr+0x87/0xb0
  SyS_setxattr+0xf/0x20
  entry_SYSCALL_64_fastpath+0x18/0xad

Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-06-21 21:17:10 -04:00
Andreas Dilger
e50e5129f3 ext4: xattr-in-inode support
Large xattr support is implemented for EXT4_FEATURE_INCOMPAT_EA_INODE.

If the size of an xattr value is larger than will fit in a single
external block, then the xattr value will be saved into the body
of an external xattr inode.

The also helps support a larger number of xattr, since only the headers
will be stored in the in-inode space or the single external block.

The inode is referenced from the xattr header via "e_value_inum",
which was formerly "e_value_block", but that field was never used.
The e_value_size still contains the xattr size so that listing
xattrs does not need to look up the inode if the data is not accessed.

struct ext4_xattr_entry {
        __u8    e_name_len;     /* length of name */
        __u8    e_name_index;   /* attribute name index */
        __le16  e_value_offs;   /* offset in disk block of value */
        __le32  e_value_inum;   /* inode in which value is stored */
        __le32  e_value_size;   /* size of attribute value */
        __le32  e_hash;         /* hash value of name and value */
        char    e_name[0];      /* attribute name */
};

The xattr inode is marked with the EXT4_EA_INODE_FL flag and also
holds a back-reference to the owning inode in its i_mtime field,
allowing the ext4/e2fsck to verify the correct inode is accessed.

[ Applied fix by Dan Carpenter to avoid freeing an ERR_PTR. ]

Lustre-Jira: https://jira.hpdd.intel.com/browse/LU-80
Lustre-bugzilla: https://bugzilla.lustre.org/show_bug.cgi?id=4424
Signed-off-by: Kalpak Shah <kalpak.shah@sun.com>
Signed-off-by: James Simmons <uja.ornl@gmail.com>
Signed-off-by: Andreas Dilger <andreas.dilger@intel.com>
Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
2017-06-21 21:10:32 -04:00
Artem Blagodarenko
e08ac99fa2 ext4: add largedir feature
This INCOMPAT_LARGEDIR feature allows larger directories to be created
in ldiskfs, both with directory sizes over 2GB and and a maximum htree
depth of 3 instead of the current limit of 2. These features are needed
in order to exceed the current limit of approximately 10M entries in a
single directory.

This patch was originally written by Yang Sheng to support the Lustre server.

[ Bumped the credits needed to update an indexed directory -- tytso ]

Signed-off-by: Liang Zhen <liang.zhen@intel.com>
Signed-off-by: Yang Sheng <yang.sheng@intel.com>
Signed-off-by: Artem Blagodarenko <artem.blagodarenko@seagate.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
2017-06-21 21:09:57 -04:00
Goldwyn Rodrigues
728fbc0e10 ext4: nowait aio support
Return EAGAIN if any of the following checks fail for direct I/O:
  + i_rwsem is lockable
  + Writing beyond end of file (will trigger allocation)
  + Blocks are not allocated at the write location

Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-20 07:12:03 -06:00
Christoph Hellwig
fdd050b5b3 Merge branch 'uuid-types' of bombadil.infradead.org:public_git/uuid into nvme-base 2017-06-13 11:45:14 +02:00
Jens Axboe
8f66439eec Linux 4.12-rc5
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 kVF+osWyXrZo5cTwkwapHW/KNu4VJwAx2D1wrlxKDVG5AOrULH1pYOYGOpApEkZU
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 =m2Gx
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Merge tag 'v4.12-rc5' into for-4.13/block

We've already got a few conflicts and upcoming work depends on some of the
changes that have gone into mainline as regression fixes for this series.

Pull in 4.12-rc5 to resolve these conflicts and make it easier on down stream
trees to continue working on 4.13 changes.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-12 08:30:13 -06:00
Christoph Hellwig
4e4cbee93d block: switch bios to blk_status_t
Replace bi_error with a new bi_status to allow for a clear conversion.
Note that device mapper overloaded bi_error with a private value, which
we'll have to keep arround at least for now and thus propagate to a
proper blk_status_t value.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-06-09 09:27:32 -06:00
Christoph Hellwig
85787090a2 fs: switch ->s_uuid to uuid_t
For some file systems we still memcpy into it, but in various places this
already allows us to use the proper uuid helpers.  More to come..

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Acked-by: Mimi Zohar <zohar@linux.vnet.ibm.com> (Changes to IMA/EVM)
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2017-06-05 16:59:12 +02:00
Jan Kara
67a7d5f561 ext4: fix fdatasync(2) after extent manipulation operations
Currently, extent manipulation operations such as hole punch, range
zeroing, or extent shifting do not record the fact that file data has
changed and thus fdatasync(2) has a work to do. As a result if we crash
e.g. after a punch hole and fdatasync, user can still possibly see the
punched out data after journal replay. Test generic/392 fails due to
these problems.

Fix the problem by properly marking that file data has changed in these
operations.

CC: stable@vger.kernel.org
Fixes: a4bb6b64e3
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-05-29 13:24:55 -04:00
Jan Kara
a056bdaae7 ext4: fix data corruption for mmap writes
mpage_submit_page() can race with another process growing i_size and
writing data via mmap to the written-back page. As mpage_submit_page()
samples i_size too early, it may happen that ext4_bio_write_page()
zeroes out too large tail of the page and thus corrupts user data.

Fix the problem by sampling i_size only after the page has been
write-protected in page tables by clear_page_dirty_for_io() call.

Reported-by: Michael Zimmer <michael@swarm64.com>
CC: stable@vger.kernel.org
Fixes: cb20d51883
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-05-26 17:45:45 -04:00
Jan Kara
4f8caa60a5 ext4: fix data corruption with EXT4_GET_BLOCKS_ZERO
When ext4_map_blocks() is called with EXT4_GET_BLOCKS_ZERO to zero-out
allocated blocks and these blocks are actually converted from unwritten
extent the following race can happen:

CPU0					CPU1

page fault				page fault
...					...
ext4_map_blocks()
  ext4_ext_map_blocks()
    ext4_ext_handle_unwritten_extents()
      ext4_ext_convert_to_initialized()
	- zero out converted extent
	ext4_zeroout_es()
	  - inserts extent as initialized in status tree

					ext4_map_blocks()
					  ext4_es_lookup_extent()
					    - finds initialized extent
					write data
  ext4_issue_zeroout()
    - zeroes out new extent overwriting data

This problem can be reproduced by generic/340 for the fallocated case
for the last block in the file.

Fix the problem by avoiding zeroing out the area we are mapping with
ext4_map_blocks() in ext4_ext_convert_to_initialized(). It is pointless
to zero out this area in the first place as the caller asked us to
convert the area to initialized because he is just going to write data
there before the transaction finishes. To achieve this we delete the
special case of zeroing out full extent as that will be handled by the
cases below zeroing only the part of the extent that needs it. We also
instruct ext4_split_extent() that the middle of extent being split
contains data so that ext4_split_extent_at() cannot zero out full extent
in case of ENOSPC.

CC: stable@vger.kernel.org
Fixes: 12735f8819
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-05-26 17:40:52 -04:00
Tahsin Erdogan
b8cb5a545c ext4: fix quota charging for shared xattr blocks
ext4_xattr_block_set() calls dquot_alloc_block() to charge for an xattr
block when new references are made. However if dquot_initialize() hasn't
been called on an inode, request for charging is effectively ignored
because ext4_inode_info->i_dquot is not initialized yet.

Add dquot_initialize() to call paths that lead to ext4_xattr_block_set().

Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
2017-05-24 18:24:07 -04:00
Eric Biggers
c41d342b39 ext4: remove redundant check for encrypted file on dio write path
Currently we don't allow direct I/O on encrypted regular files, so in
such cases we return 0 early in ext4_direct_IO().  There was also an
additional BUG_ON() check in ext4_direct_IO_write(), but it can never be
hit because of the earlier check for the exact same condition in
ext4_direct_IO().  There was also no matching check on the read path,
which made the write path specific check seem very ad-hoc.

Just remove the unnecessary BUG_ON().

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: David Gstir <david@sigma-star.at>
Reviewed-by: Jan Kara <jack@suse.cz>
2017-05-24 18:20:31 -04:00
Eric Biggers
d6b975504e ext4: remove unused d_name argument from ext4_search_dir() et al.
Now that we are passing a struct ext4_filename, we do not need to pass
around the original struct qstr too.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
2017-05-24 18:10:49 -04:00
Eric Biggers
e5465795ca ext4: fix off-by-one error when writing back pages before dio read
The 'lend' argument of filemap_write_and_wait_range() is inclusive, so
we need to subtract 1 from pos + count.

Note that 'count' is guaranteed to be nonzero since
ext4_file_read_iter() returns early when given a 0 count.

Fixes: 16c5468859 ("ext4: Allow parallel DIO reads")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
2017-05-24 18:05:29 -04:00
Eryu Guan
624327f879 ext4: fix off-by-one on max nr_pages in ext4_find_unwritten_pgoff()
ext4_find_unwritten_pgoff() is used to search for offset of hole or
data in page range [index, end] (both inclusive), and the max number
of pages to search should be at least one, if end == index.
Otherwise the only page is missed and no hole or data is found,
which is not correct.

When block size is smaller than page size, this can be demonstrated
by preallocating a file with size smaller than page size and writing
data to the last block. E.g. run this xfs_io command on a 1k block
size ext4 on x86_64 host.

  # xfs_io -fc "falloc 0 3k" -c "pwrite 2k 1k" \
  	    -c "seek -d 0" /mnt/ext4/testfile
  wrote 1024/1024 bytes at offset 2048
  1 KiB, 1 ops; 0.0000 sec (42.459 MiB/sec and 43478.2609 ops/sec)
  Whence  Result
  DATA    EOF

Data at offset 2k was missed, and lseek(2) returned ENXIO.

This is unconvered by generic/285 subtest 07 and 08 on ppc64 host,
where pagesize is 64k. Because a recent change to generic/285
reduced the preallocated file size to smaller than 64k.

Signed-off-by: Eryu Guan <eguan@redhat.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
2017-05-24 18:02:20 -04:00
Konstantin Khlebnikov
887a973061 ext4: keep existing extra fields when inode expands
ext4_expand_extra_isize() should clear only space between old and new
size.

Fixes: 6dd4ee7cab # v2.6.23
Cc: stable@vger.kernel.org
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-05-21 22:36:23 -04:00
Konstantin Khlebnikov
9651e6b2e2 ext4: handle the rest of ext4_mb_load_buddy() ENOMEM errors
I've got another report about breaking ext4 by ENOMEM error returned from
ext4_mb_load_buddy() caused by memory shortage in memory cgroup.
This time inside ext4_discard_preallocations().

This patch replaces ext4_error() with ext4_warning() where errors returned
from ext4_mb_load_buddy() are not fatal and handled by caller:
* ext4_mb_discard_group_preallocations() - called before generating ENOSPC,
  we'll try to discard other group or return ENOSPC into user-space.
* ext4_trim_all_free() - just stop trimming and return ENOMEM from ioctl.

Some callers cannot handle errors, thus __GFP_NOFAIL is used for them:
* ext4_discard_preallocations()
* ext4_mb_discard_lg_preallocations()

Fixes: adb7ef600c ("ext4: use __GFP_NOFAIL in ext4_free_blocks()")
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-05-21 22:35:23 -04:00
Jan Kara
3f1d5bad3f ext4: fix off-by-in in loop termination in ext4_find_unwritten_pgoff()
There is an off-by-one error in loop termination conditions in
ext4_find_unwritten_pgoff() since 'end' may index a page beyond end of
desired range if 'endoff' is page aligned. It doesn't have any visible
effects but still it is good to fix it.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-05-21 22:34:23 -04:00
Jan Kara
7d95eddf31 ext4: fix SEEK_HOLE
Currently, SEEK_HOLE implementation in ext4 may both return that there's
a hole at some offset although that offset already has data and skip
some holes during a search for the next hole. The first problem is
demostrated by:

xfs_io -c "falloc 0 256k" -c "pwrite 0 56k" -c "seek -h 0" file
wrote 57344/57344 bytes at offset 0
56 KiB, 14 ops; 0.0000 sec (2.054 GiB/sec and 538461.5385 ops/sec)
Whence	Result
HOLE	0

Where we can see that SEEK_HOLE wrongly returned offset 0 as containing
a hole although we have written data there. The second problem can be
demonstrated by:

xfs_io -c "falloc 0 256k" -c "pwrite 0 56k" -c "pwrite 128k 8k"
       -c "seek -h 0" file

wrote 57344/57344 bytes at offset 0
56 KiB, 14 ops; 0.0000 sec (1.978 GiB/sec and 518518.5185 ops/sec)
wrote 8192/8192 bytes at offset 131072
8 KiB, 2 ops; 0.0000 sec (2 GiB/sec and 500000.0000 ops/sec)
Whence	Result
HOLE	139264

Where we can see that hole at offsets 56k..128k has been ignored by the
SEEK_HOLE call.

The underlying problem is in the ext4_find_unwritten_pgoff() which is
just buggy. In some cases it fails to update returned offset when it
finds a hole (when no pages are found or when the first found page has
higher index than expected), in some cases conditions for detecting hole
are just missing (we fail to detect a situation where indices of
returned pages are not contiguous).

Fix ext4_find_unwritten_pgoff() to properly detect non-contiguous page
indices and also handle all cases where we got less pages then expected
in one place and handle it properly there.

CC: stable@vger.kernel.org
Fixes: c8c0df241c
CC: Zheng Liu <wenqing.lz@taobao.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-05-21 22:33:23 -04:00
Jan Kara
964edf66bf ext4: clear lockdep subtype for quota files on quota off
Quota files have special ranking of i_data_sem lock. We inform lockdep
about it when turning on quotas however when turning quotas off, we
don't clear the lockdep subclass from i_data_sem lock and thus when the
inode gets later reused for a normal file or directory, lockdep gets
confused and complains about possible deadlocks. Fix the problem by
resetting lockdep subclass of i_data_sem on quota off.

Cc: stable@vger.kernel.org
Fixes: daf647d2dd
Reported-and-tested-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-05-21 22:31:23 -04:00
Dan Williams
f5705aa8cf dax, xfs, ext4: compile out iomap-dax paths in the FS_DAX=n case
Tetsuo reports:

  fs/built-in.o: In function `xfs_file_iomap_end':
  xfs_iomap.c:(.text+0xe0ef9): undefined reference to `put_dax'
  fs/built-in.o: In function `xfs_file_iomap_begin':
  xfs_iomap.c:(.text+0xe1a7f): undefined reference to `dax_get_by_host'
  make: *** [vmlinux] Error 1
  $ grep DAX .config
  CONFIG_DAX=m
  # CONFIG_DEV_DAX is not set
  # CONFIG_FS_DAX is not set

When FS_DAX=n we can/must throw away the dax code in filesystems.
Implement 'fs_' versions of dax_get_by_host() and put_dax() that are
nops in the FS_DAX=n case.

Cc: <linux-xfs@vger.kernel.org>
Cc: <linux-ext4@vger.kernel.org>
Cc: Jan Kara <jack@suse.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: "Darrick J. Wong" <darrick.wong@oracle.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Tested-by: Tony Luck <tony.luck@intel.com>
Fixes: ef51042472 ("block, dax: move 'select DAX' from BLOCK to FS_DAX")
Reported-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-05-13 17:52:16 -07:00
Linus Torvalds
1251704a63 Merge branch 'akpm' (patches from Andrew)
Merge misc fixes from Andrew Morton:
 "15 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  mm, docs: update memory.stat description with workingset* entries
  mm: vmscan: scan until it finds eligible pages
  mm, thp: copying user pages must schedule on collapse
  dax: fix PMD data corruption when fault races with write
  dax: fix data corruption when fault races with write
  ext4: return to starting transaction in ext4_dax_huge_fault()
  mm: fix data corruption due to stale mmap reads
  dax: prevent invalidation of mapped DAX entries
  Tigran has moved
  mm, vmalloc: fix vmalloc users tracking properly
  mm/khugepaged: add missed tracepoint for collapse_huge_page_swapin
  gcov: support GCC 7.1
  mm, vmstat: Remove spurious WARN() during zoneinfo print
  time: delete current_fs_time()
  hwpoison, memcg: forcibly uncharge LRU pages
2017-05-13 09:49:35 -07:00
Jan Kara
fb26a1cbed ext4: return to starting transaction in ext4_dax_huge_fault()
DAX will return to locking exceptional entry before mapping blocks for a
page fault to fix possible races with concurrent writes.  To avoid lock
inversion between exceptional entry lock and transaction start, start
the transaction already in ext4_dax_huge_fault().

Fixes: 9f141d6ef6
Link: http://lkml.kernel.org/r/20170510085419.27601-4-jack@suse.cz
Signed-off-by: Jan Kara <jack@suse.cz>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-05-12 15:57:16 -07:00
Linus Torvalds
0fcc3ab23d Merge branch 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm
Pull libnvdimm fixes from Dan Williams:
 "Incremental fixes and a small feature addition on top of the main
  libnvdimm 4.12 pull request:

   - Geert noticed that tinyconfig was bloated by BLOCK selecting DAX.
     The size regression is fixed by moving all dax helpers into the
     dax-core and only specifying "select DAX" for FS_DAX and
     dax-capable drivers. He also asked for clarification of the
     NR_DEV_DAX config option which, on closer look, does not need to be
     a config option at all. Mike also throws in a DEV_DAX_PMEM fixup
     for good measure.

   - Ben's attention to detail on -stable patch submissions caught a
     case where the recent fixes to arch_copy_from_iter_pmem() missed a
     condition where we strand dirty data in the cache. This is tagged
     for -stable and will also be included in the rework of the pmem api
     to a proposed {memcpy,copy_user}_flushcache() interface for 4.13.

   - Vishal adds a feature that missed the initial pull due to pending
     review feedback. It allows the kernel to clear media errors when
     initializing a BTT (atomic sector update driver) instance on a pmem
     namespace.

   - Ross noticed that the dax_device + dax_operations conversion broke
     __dax_zero_page_range(). The nvdimm unit tests fail to check this
     path, but xfstests immediately trips over it. No excuse for missing
     this before submitting the 4.12 pull request.

  These all pass the nvdimm unit tests and an xfstests spot check. The
  set has received a build success notification from the kbuild robot"

* 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  filesystem-dax: fix broken __dax_zero_page_range() conversion
  libnvdimm, btt: ensure that initializing metadata clears poison
  libnvdimm: add an atomic vs process context flag to rw_bytes
  x86, pmem: Fix cache flushing for iovec write < 8 bytes
  device-dax: kill NR_DEV_DAX
  block, dax: move "select DAX" from BLOCK to FS_DAX
  device-dax: Tell kbuild DEV_DAX_PMEM depends on DEV_DAX
2017-05-12 15:43:10 -07:00
Linus Torvalds
bf5f89463f Merge branch 'akpm' (patches from Andrew)
Merge more updates from Andrew Morton:

 - the rest of MM

 - various misc things

 - procfs updates

 - lib/ updates

 - checkpatch updates

 - kdump/kexec updates

 - add kvmalloc helpers, use them

 - time helper updates for Y2038 issues. We're almost ready to remove
   current_fs_time() but that awaits a btrfs merge.

 - add tracepoints to DAX

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (114 commits)
  drivers/staging/ccree/ssi_hash.c: fix build with gcc-4.4.4
  selftests/vm: add a test for virtual address range mapping
  dax: add tracepoint to dax_insert_mapping()
  dax: add tracepoint to dax_writeback_one()
  dax: add tracepoints to dax_writeback_mapping_range()
  dax: add tracepoints to dax_load_hole()
  dax: add tracepoints to dax_pfn_mkwrite()
  dax: add tracepoints to dax_iomap_pte_fault()
  mtd: nand: nandsim: convert to memalloc_noreclaim_*()
  treewide: convert PF_MEMALLOC manipulations to new helpers
  mm: introduce memalloc_noreclaim_{save,restore}
  mm: prevent potential recursive reclaim due to clearing PF_MEMALLOC
  mm/huge_memory.c: deposit a pgtable for DAX PMD faults when required
  mm/huge_memory.c: use zap_deposited_table() more
  time: delete CURRENT_TIME_SEC and CURRENT_TIME
  gfs2: replace CURRENT_TIME with current_time
  apparmorfs: replace CURRENT_TIME with current_time()
  lustre: replace CURRENT_TIME macro
  fs: ubifs: replace CURRENT_TIME_SEC with current_time
  fs: ufs: use ktime_get_real_ts64() for birthtime
  ...
2017-05-08 18:17:56 -07:00
Michal Hocko
a7c3e901a4 mm: introduce kv[mz]alloc helpers
Patch series "kvmalloc", v5.

There are many open coded kmalloc with vmalloc fallback instances in the
tree.  Most of them are not careful enough or simply do not care about
the underlying semantic of the kmalloc/page allocator which means that
a) some vmalloc fallbacks are basically unreachable because the kmalloc
part will keep retrying until it succeeds b) the page allocator can
invoke a really disruptive steps like the OOM killer to move forward
which doesn't sound appropriate when we consider that the vmalloc
fallback is available.

As it can be seen implementing kvmalloc requires quite an intimate
knowledge if the page allocator and the memory reclaim internals which
strongly suggests that a helper should be implemented in the memory
subsystem proper.

Most callers, I could find, have been converted to use the helper
instead.  This is patch 6.  There are some more relying on __GFP_REPEAT
in the networking stack which I have converted as well and Eric Dumazet
was not opposed [2] to convert them as well.

[1] http://lkml.kernel.org/r/20170130094940.13546-1-mhocko@kernel.org
[2] http://lkml.kernel.org/r/1485273626.16328.301.camel@edumazet-glaptop3.roam.corp.google.com

This patch (of 9):

Using kmalloc with the vmalloc fallback for larger allocations is a
common pattern in the kernel code.  Yet we do not have any common helper
for that and so users have invented their own helpers.  Some of them are
really creative when doing so.  Let's just add kv[mz]alloc and make sure
it is implemented properly.  This implementation makes sure to not make
a large memory pressure for > PAGE_SZE requests (__GFP_NORETRY) and also
to not warn about allocation failures.  This also rules out the OOM
killer as the vmalloc is a more approapriate fallback than a disruptive
user visible action.

This patch also changes some existing users and removes helpers which
are specific for them.  In some cases this is not possible (e.g.
ext4_kvmalloc, libcfs_kvzalloc) because those seems to be broken and
require GFP_NO{FS,IO} context which is not vmalloc compatible in general
(note that the page table allocation is GFP_KERNEL).  Those need to be
fixed separately.

While we are at it, document that __vmalloc{_node} about unsupported gfp
mask because there seems to be a lot of confusion out there.
kvmalloc_node will warn about GFP_KERNEL incompatible (which are not
superset) flags to catch new abusers.  Existing ones would have to die
slowly.

[sfr@canb.auug.org.au: f2fs fixup]
  Link: http://lkml.kernel.org/r/20170320163735.332e64b7@canb.auug.org.au
Link: http://lkml.kernel.org/r/20170306103032.2540-2-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>	[ext4 part]
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-05-08 17:15:12 -07:00
Linus Torvalds
677375cef8 Only bug fixes and cleanups for this merge window.
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Merge tag 'fscrypt_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/fscrypt

Pull fscrypt updates from Ted Ts'o:
 "Only bug fixes and cleanups for this merge window"

* tag 'fscrypt_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/fscrypt:
  fscrypt: correct collision claim for digested names
  MAINTAINERS: fscrypt: update mailing list, patchwork, and git
  ext4: clean up ext4_match() and callers
  f2fs: switch to using fscrypt_match_name()
  ext4: switch to using fscrypt_match_name()
  fscrypt: introduce helper function for filename matching
  fscrypt: avoid collisions when presenting long encrypted filenames
  f2fs: check entire encrypted bigname when finding a dentry
  ubifs: check for consistent encryption contexts in ubifs_lookup()
  f2fs: sync f2fs_lookup() with ext4_lookup()
  ext4: remove "nokey" check from ext4_lookup()
  fscrypt: fix context consistency check when key(s) unavailable
  fscrypt: Remove __packed from fscrypt_policy
  fscrypt: Move key structure and constants to uapi
  fscrypt: remove fscrypt_symlink_data_len()
  fscrypt: remove unnecessary checks for NULL operations
2017-05-08 11:40:34 -07:00
Linus Torvalds
dd727dad37 Add GETFSMAP support; some performance improvements for very large
file systems and for random write workloads into a preallocated file;
 bug fixes and cleanups.
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Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

Pull ext4 updates from Ted Ts'o:

 - add GETFSMAP support

 - some performance improvements for very large file systems and for
   random write workloads into a preallocated file

 - bug fixes and cleanups.

* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  jbd2: cleanup write flags handling from jbd2_write_superblock()
  ext4: mark superblock writes synchronous for nobarrier mounts
  ext4: inherit encryption xattr before other xattrs
  ext4: replace BUG_ON with WARN_ONCE in ext4_end_bio()
  ext4: avoid unnecessary transaction stalls during writeback
  ext4: preload block group descriptors
  ext4: make ext4_shutdown() static
  ext4: support GETFSMAP ioctls
  vfs: add common GETFSMAP ioctl definitions
  ext4: evict inline data when writing to memory map
  ext4: remove ext4_xattr_check_entry()
  ext4: rename ext4_xattr_check_names() to ext4_xattr_check_entries()
  ext4: merge ext4_xattr_list() into ext4_listxattr()
  ext4: constify static data that is never modified
  ext4: trim return value and 'dir' argument from ext4_insert_dentry()
  jbd2: fix dbench4 performance regression for 'nobarrier' mounts
  jbd2: Fix lockdep splat with generic/270 test
  mm: retry writepages() on ENOMEM when doing an data integrity writeback
2017-05-08 11:30:05 -07:00
Dan Williams
ef51042472 block, dax: move "select DAX" from BLOCK to FS_DAX
For configurations that do not enable DAX filesystems or drivers, do not
require the DAX core to be built.

Given that the 'direct_access' method has been removed from
'block_device_operations', we can also go ahead and remove the
block-related dax helper functions from fs/block_dev.c to
drivers/dax/super.c. This keeps dax details out of the block layer and
lets the DAX core be built as a module in the FS_DAX=n case.

Filesystems need to include dax.h to call bdev_dax_supported().

Cc: linux-xfs@vger.kernel.org
Cc: Jens Axboe <axboe@kernel.dk>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: "Darrick J. Wong" <darrick.wong@oracle.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Reviewed-by: Jan Kara <jack@suse.com>
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-05-08 10:55:27 -07:00
Linus Torvalds
53ef7d0e20 libnvdimm for 4.12
* Region media error reporting: A libnvdimm region device is the parent
 to one or more namespaces. To date, media errors have been reported via
 the "badblocks" attribute attached to pmem block devices for namespaces
 in "raw" or "memory" mode. Given that namespaces can be in "device-dax"
 or "btt-sector" mode this new interface reports media errors
 generically, i.e. independent of namespace modes or state. This
 subsequently allows userspace tooling to craft "ACPI 6.1 Section
 9.20.7.6 Function Index 4 - Clear Uncorrectable Error" requests and
 submit them via the ioctl path for NVDIMM root bus devices.
 
 * Introduce 'struct dax_device' and 'struct dax_operations': Prompted by
 a request from Linus and feedback from Christoph this allows for dax
 capable drivers to publish their own custom dax operations. This fixes
 the broken assumption that all dax operations are related to a
 persistent memory device, and makes it easier for other architectures
 and platforms to add customized persistent memory support.
 
 * 'libnvdimm' core updates: A new "deep_flush" sysfs attribute is
 available for storage appliance applications to manually trigger memory
 controllers to drain write-pending buffers that would otherwise be
 flushed automatically by the platform ADR (asynchronous-DRAM-refresh)
 mechanism at a power loss event. Support for "locked" DIMMs is included
 to prevent namespaces from surfacing when the namespace label data area
 is locked. Finally, fixes for various reported deadlocks and crashes,
 also tagged for -stable.
 
 * ACPI / nfit driver updates: General updates of the nfit driver to add
 DSM command overrides, ACPI 6.1 health state flags support, DSM payload
 debug available by default, and various fixes.
 
 Acknowledgements that came after the branch was pushed:
 
 commmit 565851c972 "device-dax: fix sysfs attribute deadlock"
 Tested-by: Yi Zhang <yizhan@redhat.com>
 
 commit 23f4984483 "libnvdimm: rework region badblocks clearing"
 Tested-by: Toshi Kani <toshi.kani@hpe.com>
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Merge tag 'libnvdimm-for-4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

Pull libnvdimm updates from Dan Williams:
 "The bulk of this has been in multiple -next releases. There were a few
  late breaking fixes and small features that got added in the last
  couple days, but the whole set has received a build success
  notification from the kbuild robot.

  Change summary:

   - Region media error reporting: A libnvdimm region device is the
     parent to one or more namespaces. To date, media errors have been
     reported via the "badblocks" attribute attached to pmem block
     devices for namespaces in "raw" or "memory" mode. Given that
     namespaces can be in "device-dax" or "btt-sector" mode this new
     interface reports media errors generically, i.e. independent of
     namespace modes or state.

     This subsequently allows userspace tooling to craft "ACPI 6.1
     Section 9.20.7.6 Function Index 4 - Clear Uncorrectable Error"
     requests and submit them via the ioctl path for NVDIMM root bus
     devices.

   - Introduce 'struct dax_device' and 'struct dax_operations': Prompted
     by a request from Linus and feedback from Christoph this allows for
     dax capable drivers to publish their own custom dax operations.
     This fixes the broken assumption that all dax operations are
     related to a persistent memory device, and makes it easier for
     other architectures and platforms to add customized persistent
     memory support.

   - 'libnvdimm' core updates: A new "deep_flush" sysfs attribute is
     available for storage appliance applications to manually trigger
     memory controllers to drain write-pending buffers that would
     otherwise be flushed automatically by the platform ADR
     (asynchronous-DRAM-refresh) mechanism at a power loss event.
     Support for "locked" DIMMs is included to prevent namespaces from
     surfacing when the namespace label data area is locked. Finally,
     fixes for various reported deadlocks and crashes, also tagged for
     -stable.

   - ACPI / nfit driver updates: General updates of the nfit driver to
     add DSM command overrides, ACPI 6.1 health state flags support, DSM
     payload debug available by default, and various fixes.

  Acknowledgements that came after the branch was pushed:

   - commmit 565851c972 "device-dax: fix sysfs attribute deadlock":
     Tested-by: Yi Zhang <yizhan@redhat.com>

   - commit 23f4984483 "libnvdimm: rework region badblocks clearing"
     Tested-by: Toshi Kani <toshi.kani@hpe.com>"

* tag 'libnvdimm-for-4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (52 commits)
  libnvdimm, pfn: fix 'npfns' vs section alignment
  libnvdimm: handle locked label storage areas
  libnvdimm: convert NDD_ flags to use bitops, introduce NDD_LOCKED
  brd: fix uninitialized use of brd->dax_dev
  block, dax: use correct format string in bdev_dax_supported
  device-dax: fix sysfs attribute deadlock
  libnvdimm: restore "libnvdimm: band aid btt vs clear poison locking"
  libnvdimm: fix nvdimm_bus_lock() vs device_lock() ordering
  libnvdimm: rework region badblocks clearing
  acpi, nfit: kill ACPI_NFIT_DEBUG
  libnvdimm: fix clear length of nvdimm_forget_poison()
  libnvdimm, pmem: fix a NULL pointer BUG in nd_pmem_notify
  libnvdimm, region: sysfs trigger for nvdimm_flush()
  libnvdimm: fix phys_addr for nvdimm_clear_poison
  x86, dax, pmem: remove indirection around memcpy_from_pmem()
  block: remove block_device_operations ->direct_access()
  block, dax: convert bdev_dax_supported() to dax_direct_access()
  filesystem-dax: convert to dax_direct_access()
  Revert "block: use DAX for partition table reads"
  ext2, ext4, xfs: retrieve dax_device for iomap operations
  ...
2017-05-05 18:49:20 -07:00
Eric Biggers
d9b9f8d5a8 ext4: clean up ext4_match() and callers
When ext4 encryption was originally merged, we were encrypting the
user-specified filename in ext4_match(), introducing a lot of additional
complexity into ext4_match() and its callers.  This has since been
changed to encrypt the filename earlier, so we can remove the gunk
that's no longer needed.  This more or less reverts ext4_search_dir()
and ext4_find_dest_de() to the way they were in the v4.0 kernel.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-05-04 11:44:40 -04:00
Eric Biggers
067d1023b6 ext4: switch to using fscrypt_match_name()
Switch ext4 directory searches to use the fscrypt_match_name() helper
function.  There should be no functional change.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-05-04 11:44:38 -04:00
Eric Biggers
6b06cdee81 fscrypt: avoid collisions when presenting long encrypted filenames
When accessing an encrypted directory without the key, userspace must
operate on filenames derived from the ciphertext names, which contain
arbitrary bytes.  Since we must support filenames as long as NAME_MAX,
we can't always just base64-encode the ciphertext, since that may make
it too long.  Currently, this is solved by presenting long names in an
abbreviated form containing any needed filesystem-specific hashes (e.g.
to identify a directory block), then the last 16 bytes of ciphertext.
This needs to be sufficient to identify the actual name on lookup.

However, there is a bug.  It seems to have been assumed that due to the
use of a CBC (ciphertext block chaining)-based encryption mode, the last
16 bytes (i.e. the AES block size) of ciphertext would depend on the
full plaintext, preventing collisions.  However, we actually use CBC
with ciphertext stealing (CTS), which handles the last two blocks
specially, causing them to appear "flipped".  Thus, it's actually the
second-to-last block which depends on the full plaintext.

This caused long filenames that differ only near the end of their
plaintexts to, when observed without the key, point to the wrong inode
and be undeletable.  For example, with ext4:

    # echo pass | e4crypt add_key -p 16 edir/
    # seq -f "edir/abcdefghijklmnopqrstuvwxyz012345%.0f" 100000 | xargs touch
    # find edir/ -type f | xargs stat -c %i | sort | uniq | wc -l
    100000
    # sync
    # echo 3 > /proc/sys/vm/drop_caches
    # keyctl new_session
    # find edir/ -type f | xargs stat -c %i | sort | uniq | wc -l
    2004
    # rm -rf edir/
    rm: cannot remove 'edir/_A7nNFi3rhkEQlJ6P,hdzluhODKOeWx5V': Structure needs cleaning
    ...

To fix this, when presenting long encrypted filenames, encode the
second-to-last block of ciphertext rather than the last 16 bytes.

Although it would be nice to solve this without depending on a specific
encryption mode, that would mean doing a cryptographic hash like SHA-256
which would be much less efficient.  This way is sufficient for now, and
it's still compatible with encryption modes like HEH which are strong
pseudorandom permutations.  Also, changing the presented names is still
allowed at any time because they are only provided to allow applications
to do things like delete encrypted directories.  They're not designed to
be used to persistently identify files --- which would be hard to do
anyway, given that they're encrypted after all.

For ease of backports, this patch only makes the minimal fix to both
ext4 and f2fs.  It leaves ubifs as-is, since ubifs doesn't compare the
ciphertext block yet.  Follow-on patches will clean things up properly
and make the filesystems use a shared helper function.

Fixes: 5de0b4d0cd ("ext4 crypto: simplify and speed up filename encryption")
Reported-by: Gwendal Grignou <gwendal@chromium.org>
Cc: stable@vger.kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-05-04 11:44:36 -04:00
Eric Biggers
8c68084bff ext4: remove "nokey" check from ext4_lookup()
Now that fscrypt_has_permitted_context() correctly handles the case
where we have the key for the parent directory but not the child, we
don't need to try to work around this in ext4_lookup().

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-05-04 11:44:33 -04:00
Jan Kara
00473374b7 ext4: mark superblock writes synchronous for nobarrier mounts
Commit b685d3d65a "block: treat REQ_FUA and REQ_PREFLUSH as
synchronous" removed REQ_SYNC flag from WRITE_FUA implementation.
generic_make_request_checks() however strips REQ_FUA flag from a bio
when the storage doesn't report volatile write cache and thus write
effectively becomes asynchronous which can lead to performance
regressions. This affects superblock writes for ext4. Fix the problem
by marking superblock writes always as synchronous.

Fixes: b685d3d65a
CC: linux-ext4@vger.kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-05-04 10:58:03 -04:00
Linus Torvalds
a3719f34fd Merge branch 'generic' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs
Pull quota, reiserfs, udf and ext2 updates from Jan Kara:
 "The branch contains changes to quota code so that it does not modify
  persistent flags in inode->i_flags (it was the only place in kernel
  doing that) and handle it inside filesystem's quotaon/off handlers
  instead.

  The branch also contains two UDF cleanups, a couple of reiserfs fixes
  and one fix for ext2 quota locking"

* 'generic' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
  ext4: Improve comments in ext4_quota_{on|off}()
  udf: use kmap_atomic for memcpy copying
  udf: use octal for permissions
  quota: Remove dquot_quotactl_ops
  reiserfs: Remove i_attrs_to_sd_attrs()
  reiserfs: Remove useless setting of i_flags
  jfs: Remove jfs_get_inode_flags()
  ext2: Remove ext2_get_inode_flags()
  ext4: Remove ext4_get_inode_flags()
  quota: Stop setting IMMUTABLE and NOATIME flags on quota files
  jfs: Set flags on quota files directly
  ext2: Set flags on quota files directly
  reiserfs: Set flags on quota files directly
  ext4: Set flags on quota files directly
  reiserfs: Protect dquot_writeback_dquots() by s_umount semaphore
  reiserfs: Make cancel_old_flush() reliable
  ext2: Call dquot_writeback_dquots() with s_umount held
  reiserfs: avoid a -Wmaybe-uninitialized warning
2017-05-03 11:35:47 -07:00
Eric Biggers
aa1dca3bd9 ext4: inherit encryption xattr before other xattrs
When using both encryption and SELinux (or another feature that requires
an xattr per file) on a filesystem with 256-byte inodes, each file's
xattrs usually spill into an external xattr block.  Currently, the
xattrs are inherited in the order ACL, security, then encryption.
Therefore, if spillage occurs, the encryption xattr will always end up
in the external block.  This is not ideal because the encryption xattrs
contain a nonce, so they will always be unique and will prevent the
external xattr blocks from being deduplicated.

To improve the situation, change the inheritance order to encryption,
ACL, then security.  This gives the encryption xattr a better chance to
be stored in-inode, allowing the other xattr(s) to be deduplicated.

Note that it may be better for userspace to format the filesystem with
512-byte inodes in this case.  However, it's not the default.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-05-02 00:49:54 -04:00
Theodore Ts'o
72d622b422 ext4: replace BUG_ON with WARN_ONCE in ext4_end_bio()
Add fallback code and a WARN_ONCE() call instead of a BUG_ON() in
the ext4_end_bio() function.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-04-30 20:08:05 -04:00
Jan Kara
dddbd6ac8f ext4: avoid unnecessary transaction stalls during writeback
Currently ext4_writepages() submits all pages with transaction started.
When no page needs block allocation or extent conversion we can submit
all dirty pages in the inode while holding a single transaction handle
and when device is congested this can take significant amount of time.
Thus ext4_writepages() can block transaction commits for extended
periods of time.

Take for example a simple benchmark simulating PostgreSQL database
(pgioperf in mmtest). The benchmark runs 16 processes doing random reads
from a huge file, one process doing random writes to the huge file, and
one process doing sequential writes to a small files and frequently
running fsync. With unpatched kernel transaction commits take on average
~18s with standard deviation of ~41s, top 5 commit times are:

274.466639s, 126.467347s, 86.992429s, 34.351563s, 31.517653s.

After this patch transaction commits take on average 0.1s with standard
deviation of 0.15s, top 5 commit times are:

0.563792s, 0.519980s, 0.509841s, 0.471700s, 0.469899s

[ Modified so we use an explicit do_map flag instead of relying on
  io_end not being allocated, the since io_end->inode is needed for I/O
  error handling. -- tytso ]

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-04-30 18:29:10 -04:00
Andrew Perepechko
85c8f176a6 ext4: preload block group descriptors
With enabled meta_bg option block group descriptors
reading IO is not sequential and requires optimization.

Signed-off-by: Andrew Perepechko <andrew.perepechko@seagate.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-04-30 00:46:35 -04:00
Eric Biggers
1a20a63084 ext4: make ext4_shutdown() static
Make the ext4_shutdown() function static, as suggested by running sparse
('make C=2 fs/ext4/').  This was the only such warning in fs/ext4/.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-04-30 00:40:44 -04:00
Darrick J. Wong
0c9ec4beec ext4: support GETFSMAP ioctls
Support the GETFSMAP ioctls so that we can use the xfs free space
management tools to probe ext4 as well.  Note that this is a partial
implementation -- we only report fixed-location metadata and free space;
everything else is reported as "unknown".

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-04-30 00:36:53 -04:00
Eric Biggers
7b4cc9787f ext4: evict inline data when writing to memory map
Currently the case of writing via mmap to a file with inline data is not
handled.  This is maybe a rare case since it requires a writable memory
map of a very small file, but it is trivial to trigger with on
inline_data filesystem, and it causes the
'BUG_ON(ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA));' in
ext4_writepages() to be hit:

    mkfs.ext4 -O inline_data /dev/vdb
    mount /dev/vdb /mnt
    xfs_io -f /mnt/file \
	-c 'pwrite 0 1' \
	-c 'mmap -w 0 1m' \
	-c 'mwrite 0 1' \
	-c 'fsync'

	kernel BUG at fs/ext4/inode.c:2723!
	invalid opcode: 0000 [#1] SMP
	CPU: 1 PID: 2532 Comm: xfs_io Not tainted 4.11.0-rc1-xfstests-00301-g071d9acf3d1f #633
	Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-20170228_101828-anatol 04/01/2014
	task: ffff88003d3a8040 task.stack: ffffc90000300000
	RIP: 0010:ext4_writepages+0xc89/0xf8a
	RSP: 0018:ffffc90000303ca0 EFLAGS: 00010283
	RAX: 0000028410000000 RBX: ffff8800383fa3b0 RCX: ffffffff812afcdc
	RDX: 00000a9d00000246 RSI: ffffffff81e660e0 RDI: 0000000000000246
	RBP: ffffc90000303dc0 R08: 0000000000000002 R09: 869618e8f99b4fa5
	R10: 00000000852287a2 R11: 00000000a03b49f4 R12: ffff88003808e698
	R13: 0000000000000000 R14: 7fffffffffffffff R15: 7fffffffffffffff
	FS:  00007fd3e53094c0(0000) GS:ffff88003e400000(0000) knlGS:0000000000000000
	CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
	CR2: 00007fd3e4c51000 CR3: 000000003d554000 CR4: 00000000003406e0
	Call Trace:
	 ? _raw_spin_unlock+0x27/0x2a
	 ? kvm_clock_read+0x1e/0x20
	 do_writepages+0x23/0x2c
	 ? do_writepages+0x23/0x2c
	 __filemap_fdatawrite_range+0x80/0x87
	 filemap_write_and_wait_range+0x67/0x8c
	 ext4_sync_file+0x20e/0x472
	 vfs_fsync_range+0x8e/0x9f
	 ? syscall_trace_enter+0x25b/0x2d0
	 vfs_fsync+0x1c/0x1e
	 do_fsync+0x31/0x4a
	 SyS_fsync+0x10/0x14
	 do_syscall_64+0x69/0x131
	 entry_SYSCALL64_slow_path+0x25/0x25

We could try to be smart and keep the inline data in this case, or at
least support delayed allocation when allocating the block, but these
solutions would be more complicated and don't seem worthwhile given how
rare this case seems to be.  So just fix the bug by calling
ext4_convert_inline_data() when we're asked to make a page writable, so
that any inline data gets evicted, with the block allocated immediately.

Reported-by: Nick Alcock <nick.alcock@oracle.com>
Cc: stable@vger.kernel.org
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-04-30 00:10:50 -04:00
Eric Biggers
6ba644b9fd ext4: remove ext4_xattr_check_entry()
ext4_xattr_check_entry() was redundant with validation of the full xattr
entries list in ext4_xattr_check_entries(), which all callers also did.
ext4_xattr_check_entry() also didn't actually do correct validation;
specifically, it never checked that the value doesn't overlap the xattr
names, nor did it account for padding when checking whether the xattr
value overflows the available space.  So remove it to eliminate any
potential confusion.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-04-30 00:01:02 -04:00
Eric Biggers
2c4f992337 ext4: rename ext4_xattr_check_names() to ext4_xattr_check_entries()
ext4_xattr_check_names() actually validates both the xattr names and
values, not just the names.  So rename it to ext4_xattr_check_entries()
to avoid confusion.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-04-29 23:56:52 -04:00
Eric Biggers
ba7ea1d8f4 ext4: merge ext4_xattr_list() into ext4_listxattr()
There's no difference between ext4_xattr_list() and ext4_listxattr(), so
merge them together and just have ext4_listxattr().  Some years ago they
took different arguments, but that's no longer the case.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-04-29 23:53:17 -04:00