Commit Graph

4624 Commits (115d4b4b33540da49e5d04135417392f7c4d54fc)

Author SHA1 Message Date
Theodore Ts'o 115d4b4b33 e2fsck: flush out the superblock and bitmaps before printing final messages
A user who sees the message

***** REBOOT LINUX *****

or

***** FILE SYSTEM WAS MODIFIED *****

might think that e2fsck was complete even though we haven't finished
writing out the superblock or bitmap blocks, and then either forcibly
reboot or power cycle the box, or yank the USB key out while the
storage device is still being written (before e2fsck exits).

So rearrange the exit path of e2fsck so that we flush out the dirty
superblock/bg descriptors/bitmaps before we print the final message.
Also clean up this code so that the flow of control is easier to
understand, and add error checking to catch any errors (normally
caused by I/O errors writing to the disk) for these final writebacks.

Addresses-Debian-Bugs: #757543, #757544
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: Dan Jacobson <jidanni@jidanni.org>
2014-08-10 18:12:02 -04:00
Theodore Ts'o 84d6dd7858 tests: add the r_meta_bg_shrink test
This test checks to make sure resize2fs can properly handle a file
system which started life as a normal ext4 file system and then was
grown to a size where meta_bg was enabled, and then shrunk back below
the point where the meta_bg format is still needed.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-08-10 18:11:54 -04:00
Theodore Ts'o 755e077181 tests: add f_first_meta_bg_too_big test
The test verifies that e2fsck can properly fix a file system where the
value of s_first_meta_bg in the superblock is larger than the number
of block group descriptors in the file system.  E2fsck will fix this
by clearing the meta_bg feature.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-08-10 16:21:31 -04:00
Theodore Ts'o 9974f8c2be tests: make sure MKE2FS_FIRST_META_BG is unset while running tests
If the developer has set the MKE2FS_FIRST_META_BG environment
variable, this can cause test failures.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-08-10 16:21:31 -04:00
Theodore Ts'o c82815e509 resize2fs: disable the meta_bg feature if necessary
When shrinking a file system, if the number block groups drops below
the point where we started using the meta_bg layout, disable the
meta_bg feature and set s_first_meta_bg to zero.  This is necessary to
avoid creating an invalid/corrupted file system after the shrink.

Addresses-Debian-Bug: #756922

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reported-by: Marcin Wolcendorf <antymat+debian@chelmska.waw.pl>
Tested-by: Marcin Wolcendorf <antymat+debian@chelmska.waw.pl>
2014-08-10 16:21:08 -04:00
Theodore Ts'o 7a4352dccd e2fsck: fix file systems with an overly large s_first_meta_bg
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-08-10 16:21:08 -04:00
Theodore Ts'o f66e6ce444 libext2fs: avoid buffer overflow if s_first_meta_bg is too big
If s_first_meta_bg is greater than the of number block group
descriptor blocks, then reading or writing the block group descriptors
will end up overruning the memory buffer allocated for the
descriptors.  Fix this by limiting first_meta_bg to no more than
fs->desc_blocks.  This doesn't correct the bad s_first_meta_bg value,
but it avoids causing the e2fsprogs userspace programs from
potentially crashing.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-08-10 16:20:59 -04:00
Theodore Ts'o f00948ad1d libext2fs: have UNIX IO manager use pread64/pwrite64
Commit baa3544609 ("libext2fs: have UNIX IO manager use
pread/pwrite) causes a breakage on 32-bit systems where off_t is
32-bits for file systems larger than 4GB.  Fix this by using
pread64/pwrite64 if possible, and if pread64/pwrite64 is not present,
using pread/pwrite only if the size of off_t is at least as big as
ext2_loff_t.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-08-08 16:42:05 -04:00
Aaron Crane b6edbf6b90 debugfs: teach rdump to take multiple source arguments
[ modified to update man page by tytso ]

Signed-off-by: Aaron Crane <arc@aaroncrane.co.uk>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-08-04 18:58:23 -04:00
Aaron Crane 850fe1aca7 debugfs: refactor do_rdump()
No behaviour changes.  This will simplify the next commit.

Signed-off-by: Aaron Crane <arc@aaroncrane.co.uk>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-08-04 18:58:23 -04:00
Aaron Crane 3b0662fc95 debugfs: fix double-close bug in "rdump" and "dump -p"
Previously, both of these usages called dump_file() with a true value as
the "preserve" argument, which caused it to in turn call fix_perms() to
make the permissions on the locally-dumped file match those found on the
ext2 filesystem. fix_perms() then attempted to close(2) the file descriptor
(if any) before returning (though it didn't attempt to report on any errors
found while doing so).

However, in both of these situations, the local file being dumped had been
opened by the caller of dump_file(), which also closes it (and reports on
any errors detected when closing). This meant that both "rdump" and "dump
-p" would then emit a spurious EBADF message when trying to re-close the
local file descriptor.

Deleting the spurious close(2) call in fix_perms() fixes the problem in both
commands.

Signed-off-by: Aaron Crane <arc@aaroncrane.co.uk>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-08-04 18:58:23 -04:00
Aaron Crane 09727a0705 debugfs: be more specific in error messages
Signed-off-by: Aaron Crane <arc@aaroncrane.co.uk>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-08-04 18:58:23 -04:00
Theodore Ts'o b1988056fb libext2fs: place metadata blocks in the last flex_bg so they are contiguous
Place the allocation bitmaps and inode table blocks so they are
adjacent, even in the last flexbg.

Previously, after running "mke2fs -t ext4 DEV 286720", the layout of
the last few block groups would look like this:

Group 32: (Blocks 262145-270336) [INODE_UNINIT, ITABLE_ZEROED]
  Block bitmap at 262145 (+0), Inode bitmap at 262161 (+16)
  Inode table at 262177-262432 (+32)
Group 33: (Blocks 270337-278528) [INODE_UNINIT, BLOCK_UNINIT, ITABLE_ZEROED]
  Block bitmap at 262146 (bg #32 + 1), Inode bitmap at 262162 (bg #32 + 17)
  Inode table at 262433-262688 (bg #32 + 288)
Group 34: (Blocks 278529-286719) [INODE_UNINIT, ITABLE_ZEROED]
  Block bitmap at 262147 (bg #32 + 2), Inode bitmap at 262163 (bg #32 + 18)
  Inode table at 262689-262944 (bg #32 + 544)

Now, they look like this:

Group 32: (Blocks 262145-270336) [INODE_UNINIT, ITABLE_ZEROED]
  Block bitmap at 262145 (+0), Inode bitmap at 262148 (+3)
  Inode table at 262151-262406 (+6)
Group 33: (Blocks 270337-278528) [INODE_UNINIT, BLOCK_UNINIT, ITABLE_ZEROED]
  Block bitmap at 262146 (bg #32 + 1), Inode bitmap at 262149 (bg #32 + 4)
  Inode table at 262407-262662 (bg #32 + 262)
Group 34: (Blocks 278529-286719) [INODE_UNINIT, ITABLE_ZEROED]
  Block bitmap at 262147 (bg #32 + 2), Inode bitmap at 262150 (bg #32 + 5)
  Inode table at 262663-262918 (bg #32 + 518)

This reduces the free space fragmentation in a freshly created file
system.  It also allows the following mke2fs command to succeed:

mke2fs -t ext4 -b 4096 -O ^resize_inode -G $((2**20)) DEV 2130483

(Note that while this allows people to run mke2fs with insanely large
flexbg sizes, this is not a recommended practice, as the kernel may
refuse to resize such a file system while mounted, since it currently
tries to allocate an in-memory data structure based on the size of the
flexbg, and so a file system with a very large flexbg size will cause
the memory allocation to fail.  This will hopefully be fixed in a
future kernel release, but if the goal is to force all of the metadata
blocks to be at the beginning of the file system, it's better to use
the packed_meta_blocks configuration parameter in mke2fs.conf.)

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-08-04 18:58:23 -04:00
Theodore Ts'o 457e49981e Revert "mke2fs: prevent creation of unmountable ext4 with large flex_bg count"
This reverts commit d988201ef9.

The problem with this commit is that causes common small file system
configurations to fail.  For example:

    mke2fs -O flex_bg -b 4096 -I 1024 -F /tmp/tt 79106
    mke2fs 1.42.11 (09-Jul-2014)
    /tmp/tt: Invalid argument passed to ext2 library while setting
             up superblock

This check in ext2fs_initialize() was added to prevent the metadata
from being allocated beyond the end of the filesystem, but it is
also causing a wide range of failures for small filesystems.

We'll address this in a different way, by using a smarter algorithm
for deciding the layout of metadata blocks for the last flex block
group.

Reported-by: Andreas Dilger <andreas.dilger@intel.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-08-04 18:58:17 -04:00
Artemiy Volkov bf140bf298 debugfs: fix argument parsing in do_freefrag()
When do_freefrag() is called from debugfs, the value of optind is
not reset. Rectify that by calling reset_getopt().

Signed-off-by: Artemiy Volkov <artemiyv@acm.org>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-08-02 19:53:04 -04:00
Theodore Ts'o 3b9904967b misc: fix Makefile for profiled build
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-08-02 19:43:10 -04:00
Darrick J. Wong 07c479dd97 libext2fs: when appending to a file, don't split an index block in equal halves
When we're appending an extent to the end of a file and the index
block is full, don't split the index block into two half-full index
blocks because this leaves us with under utilized index blocks, at
least in the fallocate case.  Instead, copy the last extent from the
full block into the new block.  This isn't perfect utilization, but
there's a lot of work involved in teaching extent.c to be able to goto
a nonexistent node in a newly allocated (and empty) extent block.

This patch does not fix the general problem of keeping the extent tree
balanced.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-08-02 19:18:39 -04:00
Darrick J. Wong baa3544609 libext2fs: have UNIX IO manager use pread/pwrite
If pread/pwrite are present, have the UNIX IO manager use them for
aligned IOs (instead of the current seek -> read/write), thereby
saving us a (minor) amount of system call overhead.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-08-02 19:18:03 -04:00
Andreas Dilger af7dbe3a11 filefrag: minor code fixes and cleanups
Print filefrag_fiemap() error message to stderr instead of stdout.

Only call ioctl(EXT3_IOC_GETFLAGS) for ext{2,3,4} filesystems to
decide if the ext2 indirect block allocation heuristic shold be used.

Properly handle the the force_bmap (-B) option.

Exit with a positive error number instead of a negative one.

Signed-off-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-08-01 22:09:23 -04:00
Andreas Dilger a1363e6ad2 tests: fix f_badcluster output formatting
The f_badcluster output format depends on how libreadline formats
and outputs the commands read from stdin.  Instead of trying to
handle these differences, use an input command file, which does
not depend on external components to be consistent.

Signed-off-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-08-01 21:40:47 -04:00
Andreas Dilger 0befec4e24 misc: quiet signed/unsigned charactr compiler warnings
Quiet warnings about signed vs. unsigned character mismatch.
Use __u8 for storing UUIDs instead of char to match the superblock
s_uuid field.

Signed-off-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-08-01 21:39:27 -04:00
Theodore Ts'o 7d0109c085 tune2fs: fix uninitialized variable in remove_journal_device
This bug was introduced by commit 7dfefaf413 ("tune2fs: update
journal super block when changing UUID for fs").

Fixes-Coverity-Bug: 1229243

Reported-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-07-31 11:49:48 -04:00
Azat Khuzhin 9c2c1e9a3d tune2fs: update journal users while updating fs UUID (with external journal)
When we have fs with external journal device, and updating it's UUID, we
should update UUID in users list for that external journal device.

Before:
$ tune2fs -U clear /tmp/dev
tune2fs 1.42.10 (18-May-2014)
$ dumpe2fs /tmp/dev | fgrep UUID
dumpe2fs 1.42.10 (18-May-2014)
Filesystem UUID:          <none>
Journal UUID:             da1f2ed0-60f6-aaaa-92fd-738701418523
$ dumpe2fs /tmp/journal | fgrep users -A10
dumpe2fs 1.42.10 (18-May-2014)
Journal number of users:  2
Journal users:            0707762d-638e-4bc6-944e-ae8ee7a3359e
                          0ad849df-1041-4f0a-b1c1-2f949d6a1e37

After:
$ sudo tune2fs -U clear /tmp/dev
tune2fs 1.43-WIP (18-May-2014)
$ dumpe2fs /tmp/dev | fgrep UUID
dumpe2fs 1.42.10 (18-May-2014)
Filesystem UUID:          <none>
Journal UUID:             da1f2ed0-60f6-aaaa-92fd-738701418523
$ dumpe2fs /tmp/journal | fgrep users -A10
dumpe2fs 1.42.10 (18-May-2014)
Journal number of users:  2
Journal users:            0707762d-638e-4bc6-944e-ae8ee7a3359e
                          00000000-0000-0000-0000-000000000000

Also add some consts to avoid *magic numbers*:
- UUID_STR_SIZE
- UUID_SIZE
- JFS_USERS_MAX
- JFS_USERS_SIZE

Proposed-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Azat Khuzhin <a3at.mail@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-07-28 20:21:59 -04:00
Azat Khuzhin 7dfefaf413 tune2fs: update journal super block when changing UUID for fs.
Using -U option you can change the UUID for fs, however it will not work
for journal device, since it have a copy of this UUID inside jsb (i.e.
journal super block). So copy UUID on change into that block.

Here is the initial thread:
http://comments.gmane.org/gmane.comp.file-systems.ext4/44532

You can reproduce this by executing following commands:
$ fallocate -l100M /tmp/dev
$ fallocate -l100M /tmp/journal
$ sudo /sbin/losetup /dev/loop1 /tmp/dev
$ sudo /sbin/losetup /dev/loop0 /tmp/journal
$ mke2fs -O journal_dev /tmp/journal
$ tune2fs -U da1f2ed0-60f6-aaaa-92fd-738701418523 /tmp/journal
$ sudo mke2fs -t ext4 -J device=/dev/loop0 /dev/loop1
$ dumpe2fs -h /tmp/dev | fgrep UUID
dumpe2fs 1.43-WIP (18-May-2014)
Filesystem UUID:          8a776be9-12eb-411f-8e88-b873575ecfb6
Journal UUID:             e3d02151-e776-4865-af25-aecb7291e8e5
$ sudo e2fsck /dev/vdc
e2fsck 1.43-WIP (18-May-2014)
External journal does not support this filesystem

/dev/loop1: ********** WARNING: Filesystem still has errors **********

Reported-by: Chin Tzung Cheng <chintzung@gmail.com>
Signed-off-by: Azat Khuzhin <a3at.mail@gmail.com>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-07-28 20:21:59 -04:00
Azat Khuzhin 3e077c357c tune2fs: remove_journal_device(): use the correct block to find jsb
Signed-off-by: Azat Khuzhin <a3at.mail@gmail.com>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-07-28 20:21:59 -04:00
Azat Khuzhin 7f33024ac2 journal: use consts instead of 1024 and add helper for journal with 1k blocksize
Use EXT2_MIN_BLOCK_SIZE, JFS_MIN_JOURNAL_BLOCKS, SUPERBLOCK_SIZE, and
SUPERBLOCK_OFFSET instead of hardcoded 1024 when it is okay, and also
add a helper ext2fs_journal_sb_start() that will return start of
journal sb with special case for fs with 1k block size.

Signed-off-by: Azat Khuzhin <a3at.mail@gmail.com>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-07-28 20:21:47 -04:00
Darrick J. Wong d230dc4a3e tests: add the f_badcluster test
This should have been part of commit 9a1d614df2 ("e2fsck: fix
rule-violating lblk->pblk mappings on bigalloc filesystems") but it
accidentally got dropped when the patch was applied.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-07-28 15:37:03 -04:00
Rakesh Pandit 01824c9bbc filefrag: fix block size value
ioctl(FIGETBSZ) was used to get block size earlier but 2508eaa7
(filefrag: improvements to filefrag FIEMAP handling) moved to fstatfs
f_bsize which doesn't work well for many files systems.

Block size returned using fstatfs isn't block size but "optimal
transfer block size" as per man page.  Even stat st_blksize is
"preferred I/O block size" and in may file systems it may even vary
from file to file (POSIX).  This patch changes filefrag to use
FIGETBSZ preferentially over f_bsize.

[ Modified by tytso to add the fallback to f_bsize if FIGETBSZ fails
  for some reason ]

Signed-off-by: Rakesh Pandit <rakesh@tuxera.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-07-27 20:24:23 -04:00
Rakesh Pandit abc4697d5a filefrag: fix -B option and extents calculation for FIBMAP
29758d2 broke -B option which is useful for filesystems not supporting
FIEMAP. Also, fix extents calculation for -B which is broken since
2508eaa7.

Signed-off-by: Rakesh Pandit <rakesh@tuxera.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-07-27 19:56:27 -04:00
Darrick J. Wong 8dd650ab9a e2fsck: during pass1b delete_file, only free a cluster once
If we're forced to delete a crosslinked file, only call
ext2fs_block_alloc_stats2() on cluster boundaries, since the block
bitmaps are all cluster bitmaps at this point.  It's safe to do this
only once per cluster since we know all the blocks are going away.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-07-26 16:28:58 -04:00
Darrick J. Wong 9a1d614df2 e2fsck: fix rule-violating lblk->pblk mappings on bigalloc filesystems
As far as I can tell, logical block mappings on a bigalloc filesystem are
supposed to follow a few constraints:

 * The logical cluster offset must match the physical cluster offset.
 * A logical cluster may not map to multiple physical clusters.

Since the multiply-claimed block recovery code can be used to fix these
problems, teach e2fsck to find these transgressions and fix them.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-07-26 16:27:41 -04:00
Darrick J. Wong ff11309ecc e2fsck: perform implied cluster allocations when filling a directory hole
If we're filling a directory hole, we need to perform an implied
cluster allocation to satisfy the bigalloc rule of mapping only one
pblk to a logical cluster.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-07-26 16:07:17 -04:00
Darrick J. Wong b729b7dfab e2fsck: reserve blocks for root/lost+found directory repair
If we think we're going to need to repair either the root directory or
the lost+found directory, reserve a block at the end of pass 1 to
reduce the likelihood of an e2fsck abort while reconstructing
root/lost+found during pass 3.

If / and/or /lost+found are corrupt and duplicate processing in pass
1b allocates all the free blocks in the FS, fsck aborts with an
unusable FS since pass 3 can't recreate / or /lost+found.  If either
of those directories are missing, an admin can't easily mount the FS
and access the directory tree to move files off the injured FS and
free up space; this in turn prevents subsequent runs of e2fsck from
being able to continue repairs of the FS.

(One could migrate files manually with debugfs without the help of
path names, but it seems easier if users can simply mount the FS and
use regular FS management tools.)

[ Fixed up an obvious C trap: const char * and const char [] are not
  the same thing when you are taking the size of the parameter.
  People, run your regression tests!  Like spinach, it's good for you.  :-)
  -- tytso ]

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-07-26 15:45:42 -04:00
Darrick J. Wong 97c607b1a2 libext2fs: provide a function to set inode size
Provide an API to set i_size in an inode and take care of all required
feature flag modifications.  Refactor the code to use this new
function.

[ Moved the function to lib/ext2fs/blk_num.c, which is the rest of
  these sorts of functions live, and renamed it to be
  ext2fs_inode_size_set() instead of ext2fs_inode_set_size() to be
  consistent with the other functions in in blk_num.c -- tytso ]

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-07-26 14:34:56 -04:00
Theodore Ts'o a30a4e93f3 libext2fs: fix free block accounting for 64-bit file systems
We rely on a nasty hack to adjust the free block count where we pass
signed value into ext2fs_free_blocks_count_add(), which takes an
64-bit unsigned value, and relies on overflow and C's signed->unsigned
semantics to do the subtraction.  This works, so long as a 64-bit
signed value is used.

Unfortunately, ext2fs_block_alloc_stats2() and
ext2fs_block_alloc_stats_range(), this is not true, so on a 64-bit
file system, the free blocks accounting can get screwed up.

A simple way to demonstrate the problem is:

mke2fs -F -t ext4 -O 64bit /tmp/foo.img 1M
e2fsck -fy /tmp/foo.img

... which will result in the following e2fsck complaint:

Pass 5: Checking group summary information
Free blocks count wrong (4294968278, counted=982).
Fix? yes

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-07-26 09:25:40 -04:00
Theodore Ts'o 1e33a8b408 Fix 32/64-bit overflow when multiplying by blocks/clusters per group
There are a number of places where we need convert groups to blocks or
clusters by multiply the groups by blocks/clusters per group.
Unfortunately, both quantities are 32-bit, but the result needs to be
64-bit, and very often the cast to 64-bit gets lost.

Fix this by adding new macros, EXT2_GROUPS_TO_BLOCKS() and
EXT2_GROUPS_TO_CLUSTERS().

This should fix a bug where resizing a 64bit file system can result in
calculate_minimum_resize_size() looping forever.

Addresses-Launchpad-Bug: #1321958

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-07-26 07:40:36 -04:00
Theodore Ts'o d4ecec45ab libext2fs: use C99 initializers for the io_manager structure
Using C99 initializers makes the code a bit more readable, and it
avoids some gcc -Wall warnings regarding missing initializers.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-07-26 00:49:14 -04:00
Theodore Ts'o baab9f43bf resize2fs: radically reduce memory utilization by using rbtree bitmaps
When resizing an empty 21T file system to 28T, resize2fs was using
this much CPU time and memory:

216.98user 19.77system 4:02.92elapsed 97%CPU (0avgtext+0avgdata 4485664maxresident)k
8inputs+1068680outputs (0major+800745minor)pagefaults 0swaps

After this one-line change:

222.29user 0.49system 3:48.79elapsed 97%CPU (0avgtext+0avgdata 30080maxresident)k
8inputs+1068552outputs (0major+2497minor)pagefaults 0swaps

So this reduces the max memory utilized from 4.2GB to 29MB!

For future work, the primary place where we are spending the most cpu
time (from resize2fs -d 16) are these two places:

blocks_to_move: Memory used: 2508k/25096k (1903k/606k), time: 91.42/91.53/ 0.00

and

calculate_summary_stats: Memory used: 2508k/25612k (1908k/601k), time: 95.33/95.45/ 0.00

The calculate_summary_stats pass can be sped up by using
ext2fs_find_first_{zero,set}_block_bitmap2(), instead of iterating
over the entire block bitmap one bit at a time.

The blocks_to_move pass can be sped up by using a bitmap to store the
location of fs metadata blocks, to avoid an O(N**2) algorithm where N
is the number of groups in the file system.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-07-26 00:48:29 -04:00
Theodore Ts'o 2dbf34e505 libext2fs: fix rb_resize_bmap to handle the padding bits
The bits between end and real_end are set as a safety measure for the
kernel when it uses the bit scan instructions.  We need to take this
into account when shrinking or growing the block allocation bitmap,
before we can safely use rbtree bitmaps in resize2fs.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-07-26 00:48:29 -04:00
Theodore Ts'o 188949d7ce tests: use e2fsck -f instead of -p for resize tests
Using e2sck -f provides better debugging information if things go
wrong.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-07-26 00:48:29 -04:00
Andreas Dilger 8b90ab2b1c build: fix unused/uninitialized variable warnings
Fix a few warnings about unused and uninitialized variables.

Also fix util/subst.c to include <sys/time.h> to avoid using
undeclared functions gettimeofday() and futimes().

Signed-off-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-07-25 22:48:01 -04:00
Darrick J. Wong 57b7fabc2e e2fsck: clear uninit flag on directory extents
Directories can't have uninitialized extents, so offer to clear the
uninit flag when we find this situation.  The actual directory blocks
will be checked in pass 2 and 3 regardless of the uninit flag.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-07-25 08:50:23 -04:00
Darrick J. Wong c28c2741ba e2fsck: pass2 should not process directory blocks that are impossibly large
Currently, directories cannot be fallocated, which means that the only
way they get bigger is for the kernel to append blocks one by one.
Therefore, if we encounter a logical block offset that is too big, we
needn't bother adding it to the dblist for pass2 processing, because
it's unlikely to contain a valid directory block.  The code that
handles extent based directories also does not add toobig blocks to
the dblist.

Note that we can easily cause e2fsck to fail with ENOMEM if we start
feeding it really large logical block offsets, as the dblist
implementation will try to realloc() an array big enough to hold it.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-07-25 08:41:11 -04:00
Darrick J. Wong 0733835bf7 e2fsck: always submit logical block 0 of a directory for pass 2
Always iterate logical block 0 in a directory, even if no physical
block has been allocated.  Pass 2 will notice the lack of mapping and
offer to allocate a new directory block; this enables us to link the
directory into lost+found.

Previously, if there were no logical blocks mapped, we would fail to
pick up even block 0 of the directory for processing in pass 2.  This
meant that e2fsck never allocated a block 0 and therefore wouldn't fix
the missing . and .. entries for the directory; subsequent e2fsck runs
would complain about (yet never fix) the problem.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-07-25 08:39:45 -04:00
Darrick J. Wong 9f005a90f8 e2fsck: collapse holes in extent-based directories
If we notice a hole in the block map of an extent-based directory,
offer to collapse the hole by decreasing the logical block # of the
extent.  This saves us from pass 3's inefficient strategy, which fills
the holes by mapping in a lot of empty directory blocks.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-07-25 08:30:11 -04:00
Darrick J. Wong c23b2cc439 e2fsck: don't crash during rehash
If a user crafts a carefully constructed filesystem containing a
single directory entry block with an invalid checksum and fewer than
two entries, and then runs e2fsck to fix the filesystem, fsck will
crash when it tries to "compress" the short dir and passes a negative
dirent array length to qsort.  Therefore, don't allow directory
"compression" in this situation.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-07-25 07:21:47 -04:00
Darrick J. Wong c3470fcd60 misc: fix problems with strncat
The third argument to strncat is the maximum number of characters to
copy out of the second argument; it is not the maximum length of the
first argument.

Therefore, code in a check just in case we ever find a /sys/block/X
path long enough to hit the end of the buffer.  FWIW the longest path
I could find on my machine was 133 bytes.

Fixes-Coverity-Bug: 1252003
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-07-25 07:21:47 -04:00
Darrick J. Wong 203e13cf9c libext2fs: fix bounds check of the bitmap test range in get_free_blocks2
In the loop in ext2fs_get_free_blocks2, we ask the bitmap if there's a
range of free blocks starting at "b" and ending at "b + num - 1".
That quantity is the number of the last block in the range.  Since
ext2fs_blocks_count() returns the number of blocks and not the number
of the last block in the filesystem, the check is incorrect.

Put in a shortcut to exit the loop if finish > start, because in that
case it's obvious that we don't need to reset to the beginning of the
FS to continue the search for blocks.  This is needed to terminate the
loop because the broken test meant that b could get large enough to
equal finish, which would end the while loop.

The attached testcase shows that with the off by one error, it is
possible to throw e2fsck into an infinite loop while it tries to
find space for the inode table even though there's no space for one.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-07-25 07:11:57 -04:00
Darrick J. Wong b4f724c8a9 e2fsck: fix off-by-one bounds check on group number
Since fs->group_desc_count is the number of block groups, the number
of the last group is always one less than this count.  Fix the bounds
check to reflect that.

This flaw shouldn't have any user-visible side effects, since the
block bitmap test based on last_grp later on can handle overbig block
numbers.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-07-24 22:19:27 -04:00
Darrick J. Wong b4a4088338 e2fsck: force all block allocations to use block_found_map
During the later passes of efsck, we sometimes need to allocate and
map blocks into a file.  This can happen either by fsck directly
calling new_block() or indirectly by the library calling new_block
because it needs to allocate a block for lower level metadata (bmap2()
with BMAP_SET; block_iterate3() with BLOCK_CHANGED).

We need to force new_block to allocate blocks from the found block
map, because the FS block map could be inaccurate for various reasons:
the map is wrong, there are missing blocks, the checksum failed, etc.

Therefore, any time fsck does something that could to allocate blocks,
we need to intercept allocation requests so that they're sourced from
the found block map.  Remove the previous code that swapped bitmap
pointers as this is now unneeded.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-07-24 22:16:59 -04:00