This function really returns the number of clusters after initializing
an uninitalized block bitmap has been initialized.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
The field bg_free_blocks_count_{lo,high} in the block group
descriptor has been repurposed to hold the number of free clusters for
bigalloc functions. So rename the functions so it makes it easier to
read and audit the block allocation and block freeing code.
Note: at this point in bigalloc development we doesn't support
online resize, so this also makes it really obvious all of the places
we need to fix up to add support for online resize.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
With bigalloc changes, the i_blocks value was not correctly set (it was still
set to number of blocks being used, but in case of bigalloc, we want i_blocks
to represent the number of clusters being used). Since the quota subsystem sets
the i_blocks value, this patch fixes the quota accounting and makes sure that
the i_blocks value is set correctly.
Signed-off-by: Aditya Kali <adityakali@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
The default group preallocation size had been previously set to 512
blocks/clusters, regardless of the block/cluster size. This is
probably too big for large cluster sizes. So adjust the default so
that it is 2 megabytes or 32 clusters, whichever is larger.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Convert the free_blocks to be free_clusters to make the final revised
bigalloc changes easier to read/understand.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Convert the percpu counters s_dirtyblocks_counter and
s_freeblocks_counter in struct ext4_super_info to be
s_dirtyclusters_counter and s_freeclusters_counter.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
The ext4_free_blocks() function now has two new flags that indicate
whether a partial cluster at the beginning or the end of the block
extents should be freed or not. That will be up the caller (i.e.,
truncate), who can figure out whether partial clusters at the
beginning or the end of a block range can be freed.
We also have to update the ext4_mb_free_metadata() and
release_blocks_on_commit() machinery to be cluster-based, since it is
used by ext4_free_blocks().
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
In most of mballoc.c, we do everything in units of clusters, since the
block allocation bitmaps and buddy bitmaps are all denominated in
clusters. The one place where we do deal with absolute block numbers
is in the code that handles the preallocation regions, since in the
case of inode-based preallocation regions, the start of the
preallocation region can't be relative to the beginning of the group.
So this adds a bit of complexity, where pa_pstart and pa_lstart are
block numbers, while pa_free, pa_len, and fe_len are denominated in
units of clusters.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Change the places in fs/ext4/mballoc.c where EXT4_BLOCKS_PER_GROUP are
used to indicate the number of bits in a block bitmap (which is really
a cluster allocation bitmap in bigalloc file systems). There are
still some places in the ext4 codebase where usage of
EXT4_BLOCKS_PER_GROUP needs to be audited/fixed, in code paths that
aren't used given the initial restricted assumptions for bigalloc.
These will need to be fixed before we can relax those restrictions.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
In ext4_mb_init(), if the s_locality_group allocation fails it will
currently cause the allocations made in ext4_mb_init_backend() to
be leaked. Moving the ext4_mb_init_backend() allocation after the
s_locality_group allocation avoids that problem.
Signed-off-by: Yu Jian <yujian@whamcloud.com>
Signed-off-by: Andreas Dilger <adilger@whamcloud.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Rename mb_set_bits() to ext4_set_bits() and make it a global function
so that setup_new_group_blocks() can use it.
Signed-off-by: Yongqiang Yang <xiaoqiangnk@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
If ext4_group_add_blocks() is called with 0 block, make it return 0
without doing any extra work.
Signed-off-by: Yongqiang Yang <xiaoqiangnk@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This patch lets ext4_group_add_blocks() return an error code if it
fails, so that upper functions can handle error correctly.
Signed-off-by: Yongqiang Yang <xiaoqiangnk@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
In ext4_mb_release, we use s_mb_buddies_generated++. Although
the output is OK, but I don't think we need this extra ++.
Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
ext4_mb_load_buddy() calls ext4_get_group_info() for setting both
"grp" and "e4b->bd_info", but it could do "e4b->bd_info = grp".
Reported-by: Andreas Dilger <adilger@whamcloud.com>
Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Previously, if a stripe width was provided, then it would be used
as the preallocation granularity, with no santiy checking and no
way to override this. Now, mb_prealloc_size defaults to the smallest
multiple of stripe size that is greater than or equal to the old
default mb_prealloc_size, and this can be overridden with the sysfs
interface.
Signed-off-by: Dan Ehrenberg <dehrenberg@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
If we meet with an error in ext4_mb_add_groupinfo, we kfree
sbi->s_group_info[group >> EXT4_DESC_PER_BLOCK_BITS(sb)], but fail to
reset it to NULL. So the caller ext4_mb_init_backend will try to kfree
it again and causes a double free. So fix it by resetting it to NULL.
Some typo in comments of mballoc.c are also changed.
Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
In ext4_groupinfo_create_slab, we create ext4_groupinfo_caches within
ext4_grpinfo_slab_create_mutex, but set it outside the lock, and there
does exist some case that we may create it twice and causes a memory
leak. So set it before we call mutex_unlock.
Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
at ext4_trim_all_free() comment, there is no longer an @e4b parameter,
instead it is @group.
Reported-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
In ext4, when FITRIM is called every time, we iterate all the
groups and do trim one by one. It is a bit time wasting if the
group has been trimmed and there is no change since the last
trim.
So this patch adds a new flag in ext4_group_info->bb_state to
indicate that the group has been trimmed, and it will be cleared
if some blocks is freed(in release_blocks_on_commit). Another
trim_minlen is added in ext4_sb_info to record the last minlen
we use to trim the volume, so that if the caller provide a small
one, we will go on the trim regardless of the bb_state.
A simple test with my intel x25m ssd:
df -h shows:
/dev/sdb1 40G 21G 17G 56% /mnt/ext4
Block size: 4096
run the FITRIM with the following parameter:
range.start = 0;
range.len = UINT64_MAX;
range.minlen = 1048576;
without the patch:
[root@boyu-tm linux-2.6]# time ./ftrim /mnt/ext4/a
real 0m5.505s
user 0m0.000s
sys 0m1.224s
[root@boyu-tm linux-2.6]# time ./ftrim /mnt/ext4/a
real 0m5.359s
user 0m0.000s
sys 0m1.178s
[root@boyu-tm linux-2.6]# time ./ftrim /mnt/ext4/a
real 0m5.228s
user 0m0.000s
sys 0m1.151s
with the patch:
[root@boyu-tm linux-2.6]# time ./ftrim /mnt/ext4/a
real 0m5.625s
user 0m0.000s
sys 0m1.269s
[root@boyu-tm linux-2.6]# time ./ftrim /mnt/ext4/a
real 0m0.002s
user 0m0.000s
sys 0m0.001s
[root@boyu-tm linux-2.6]# time ./ftrim /mnt/ext4/a
real 0m0.002s
user 0m0.000s
sys 0m0.001s
A big improvement for the 2nd and 3rd run.
Even after I delete some big image files, it is still much
faster than iterating the whole disk.
[root@boyu-tm test]# time ./ftrim /mnt/ext4/a
real 0m1.217s
user 0m0.000s
sys 0m0.196s
Cc: Lukas Czerner <lczerner@redhat.com>
Reviewed-by: Andreas Dilger <adilger.kernel@dilger.ca>
Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
When we trim some free blocks in a group of ext4, we need to
calculate the free blocks properly and check whether there are
enough freed blocks left for us to trim. Current solution will
only calculate free spaces if they are large for a trim which
isn't appropriate.
Let us see a small example:
a group has 1.5M free which are 300k, 300k, 300k, 300k, 300k.
And minblocks is 1M. With current solution, we have to iterate
the whole group since these 300k will never be subtracted from
1.5M. But actually we should exit after we find the first 2
free spaces since the left 3 chunks only sum up to 900K if we
subtract the first 600K although they can't be trimed.
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
In 0f0a25b, we adjust 'len' with s_first_data_block - start, but
it could underflow in case blocksize=1K, fstrim_range.len=512 and
fstrim_range.start = 0. In this case, when we run the code:
len -= first_data_blk - start; len will be underflow to -1ULL.
In the end, although we are safe that last_group check later will limit
the trim to the whole volume, but that isn't what the user really want.
So this patch fix it. It also adds the check for 'start' like ext3 so that
we can break immediately if the start is invalid.
Cc: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
The current implementation of ext4_free_blocks() always calls
dquot_free_block This looks quite sensible in the most cases: blocks
to be freed are associated with inode and were accounted in quota and
i_blocks some time ago.
However, there is a case when blocks to free were not accounted by the
time calling ext4_free_blocks() yet:
1. delalloc is on, write_begin pre-allocated some space in quota
2. write-back happens, ext4 allocates some blocks in ext4_ext_map_blocks()
3. then ext4_ext_map_blocks() gets an error (e.g. ENOSPC) from
ext4_ext_insert_extent() and calls ext4_free_blocks().
In this scenario, ext4_free_blocks() calls dquot_free_block() who, in
turn, decrements i_blocks for blocks which were not accounted yet (due
to delalloc) After clean umount, e2fsck reports something like:
> Inode 21, i_blocks is 5080, should be 5128. Fix<y>?
because i_blocks was erroneously decremented as explained above.
The patch fixes the problem by passing the new flag
EXT4_FREE_BLOCKS_NO_QUOT_UPDATE to ext4_free_blocks(), to request
that the dquot_free_block() call be skipped.
Signed-off-by: Maxim Patlasov <maxim.patlasov@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@kernel.org
While creating fixed tracepoints for ext3, basically by porting them
from ext4, I found a lot of useless retyping, wrong type usage, useless
variable passing and other inconsistencies in the ext4 fixed tracepoint
code.
This patch cleans the fixed tracepoint code for ext4 and also simplify
some of them.
Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
metadata is not parameter of ext4_free_blocks() any more.
Signed-off-by: Yongqiang Yang <xiaoqiangnk@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This patch adds an allocation request flag to the ext4_has_free_blocks
function which enables the use of reserved blocks. This will allow a
punch hole to proceed even if the disk is full. Punching a hole may
require additional blocks to first split the extents.
Because ext4_has_free_blocks is a low level function, the flag needs
to be passed down through several functions listed below:
ext4_ext_insert_extent
ext4_ext_create_new_leaf
ext4_ext_grow_indepth
ext4_ext_split
ext4_ext_new_meta_block
ext4_mb_new_blocks
ext4_claim_free_blocks
ext4_has_free_blocks
[ext4 punch hole patch series 1/5 v7]
Signed-off-by: Allison Henderson <achender@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Mingming Cao <cmm@us.ibm.com>
We should protect reading bd_info->bb_first_free with the group lock
because otherwise we might miss some free blocks. This is not a big deal
at all, but the change to do right thing is really simple, so lets do
that.
Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Currently we are loading buddy ext4_mb_load_buddy() for every block
group we are going through in ext4_trim_fs() in many cases just to find
out that there is not enough space to be bothered with. As Amir Goldstein
suggested we can use bb_free information directly from ext4_group_info.
This commit removes ext4_mb_load_buddy() from ext4_trim_fs() and rather
get the ext4_group_info via ext4_get_group_info() and use the bb_free
information directly from that. This avoids unnecessary call to load
buddy in the case the group does not have enough free space to trim.
Loading buddy is now moved to ext4_trim_all_free().
Tested by me with xfstests 251.
Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
After taking care of all group init races, all that remains is to
remove alloc_semp from ext4_allocation_context and ext4_buddy structs.
Signed-off-by: Amir Goldstein <amir73il@users.sf.net>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
After online resize which adds new groups, some of the groups
in a buddy page may be initialized and uptodate, while other
(new ones) may be uninitialized.
The indication for init of new block groups is when ext4_mb_init_cache()
is called with an uptodate buddy page. In this case, initialized groups
on that buddy page must be skipped when initializing the buddy cache.
Signed-off-by: Amir Goldstein <amir73il@users.sf.net>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
The old routines ext4_mb_[get|put]_buddy_cache_lock(), which used
to take grp->alloc_sem for all groups on the buddy page have been
replaced with the routines ext4_mb_[get|put]_buddy_page_lock().
The new routines take both buddy and bitmap page locks to protect
against concurrent init of groups on the same buddy page.
The GROUP_NEED_INIT flag is tested again under page lock to check
if the group was initialized by another caller.
Signed-off-by: Amir Goldstein <amir73il@users.sf.net>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
The old imlementation used to take grp->alloc_sem and set the
GROUP_NEED_INIT flag, so that the buddy cache would be reloaded.
The new implementation updates the buddy cache by freeing the added
blocks and making them available for use, so there is no need to
reload the buddy cache and there is no need to take grp->alloc_sem.
Signed-off-by: Amir Goldstein <amir73il@users.sf.net>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
The block allocation code used to use jbd2_journal_get_undo_access as
a way to make changes that wouldn't show up until the commit took
place. The new multi-block allocation code has a its own way of
preventing newly freed blocks from getting reused until the commit
takes place (it avoids updating the buddy bitmaps until the commit is
done), so we don't need to use jbd2_journal_get_undo_access(), which
has extra overhead compared to jbd2_journal_get_write_access().
There was one last vestigal use of ext4_journal_get_undo_access() in
ext4_add_groupblocks(); change it to use ext4_journal_get_write_access()
and then remove the ext4_journal_get_undo_access() support.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
In preparation for the next patch, the function ext4_add_groupblocks()
is moved to mballoc.c, where it could use some static functions.
Signed-off-by: Amir Goldstein <amir73il@users.sf.net>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This is an effective revert of commit a30eec2a8: "ext4: stop issuing
discards if not supported by device". The problem is that there are
some devices that may return errors in response to a discard request
some times but not others. (One example would be a hybrid dm device
which concatenates an SSD and an HDD device).
By this logic, I also removed the error checking from ext4's FITRIM
code; so that an error from a discard will not stop the FITRIM from
trying to trim the rest of the file system.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Add missing page_cache_release in the error path of ext4_mb_load_buddy
Signed-off-by: Yang Ruirui <ruirui.r.yang@tieto.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@kernel.org
We can call kfree on uninitialized members of the s_group_info array
on an the error path. We can avoid this by kzalloc'ing the array.
This doesn't entirely solve the oops on mount if we fail down this
path; failed_mount4: frees the sbi, for one, which gets referenced
later in the failed mount paths - I haven't worked that out yet.
https://bugzilla.kernel.org/show_bug.cgi?id=30872
Reported-by: Eugene A. Shatokhin <dame_eugene@mail.ru>
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
If CONFIG_EXT4_DEBUG is enabled, then if a block allocation fails due
to disk being full, a verbose debugging message is printed, even if
the malloc-debug switch has not been enabled. Suppress the debugging
message so that nothing is printed unless malloc-debug has been turned
on.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
In ext4_mb_check_group_pa(), the current preallocation space is
replaced with a new preallocation space when the two have the same
distance from the goal block.
This doesn't actually gain us anything, so change things so that the
function only switches to the new preallocation group if its distance
from the goal block is strictly smaller than the current preallocaiton
group's distance from the goal block.
Signed-off-by: Coly Li <bosong.ly@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This patch adds comments to ext4_mb_mark_free_simple to make it more
understandable.
Signed-off-by: Coly Li <bosong.ly@taobao.com>
Cc: Alex Tomas <alex@clusterfs.com>
Cc: Theodore Tso <tytso@google.com>
In __mb_check_buddy(), look at the code below:
591 fstart = -1;
592 buddy = mb_find_buddy(e4b, 0, &max);
593 for (i = 0; i < max; i++) {
594 if (!mb_test_bit(i, buddy)) {
595 MB_CHECK_ASSERT(i >= e4b->bd_info->bb_first_free);
596 if (fstart == -1) {
597 fragments++;
598 fstart = i;
599 }
600 continue;
601 }
602 fstart = -1;
603 /* check used bits only */
604 for (j = 0; j < e4b->bd_blkbits + 1; j++) {
605 buddy2 = mb_find_buddy(e4b, j, &max2);
606 k = i >> j;
607 MB_CHECK_ASSERT(k < max2);
608 MB_CHECK_ASSERT(mb_test_bit(k, buddy2));
609 }
610 }
611 MB_CHECK_ASSERT(!EXT4_MB_GRP_NEED_INIT(e4b->bd_info));
612 MB_CHECK_ASSERT(e4b->bd_info->bb_fragments == fragments);
613
614 grp = ext4_get_group_info(sb, e4b->bd_group);
615 buddy = mb_find_buddy(e4b, 0, &max);
On line 592, buddy is fetched by mb_find_buddy() with order 0, between
line 593 to line 615, buddy is not changed, therefore there is
no need to fetch buddy again from mb_find_buddy() with order 0 again.
We can safely remove the second mb_find_buddy() on line 615.
Signed-off-by: Coly Li <bosong.ly@taobao.com>
Cc: Alex Tomas <alex@clusterfs.com>
Cc: Theodore Tso <tytso@google.com>
Current code calculate max no matter whether order is zero, it's
unnecessary. This cleanup patch sets max to "1 << (e4b->bd_blkbits
+ 3)" only when order == 0.
Signed-off-by: Coly Li <bosong.ly@taobao.com>
Cc: Alex Tomas <alex@clusterfs.com>
Cc: Theodore Tso <tytso@google.com>
