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path: root/fs/ext4/mballoc.c
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2012-02-20ext4: remove EXT4_MB_{BITMAP,BUDDY} macrosTheodore Ts'o
The EXT4_MB_BITMAP and EXT4_MB_BUDDY macros obfuscate more than they provide any abstraction. So remove them. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-02-20ext4: mark possibly unused variable in ext4_mb_normalize_request()Curt Wohlgemuth
The 'orig_size' local variable is only used in a call to mb_debug(). Mark it with '__maybe_unused'. Signed-off-by: Curt Wohlgemuth <curtw@google.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-02-20ext4: expand commit callback andBobi Jam
The per-commit callback was used by mballoc code to manage free space bitmaps after deleted blocks have been released. This patch expands it to support multiple different callbacks, to allow other things to be done after the commit has been completed. Signed-off-by: Bobi Jam <bobijam@whamcloud.com> Signed-off-by: Andreas Dilger <adilger@whamcloud.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-02-20ext4: fix race when setting bitmap_uptodate flagTheodore Ts'o
In ext4_read_{inode,block}_bitmap() we were setting bitmap_uptodate() before submitting the buffer for read. The is bad, since we check bitmap_uptodate() without locking the buffer, and so if another process is racing with us, it's possible that they will think the bitmap is uptodate even though the read has not completed yet, resulting in inodes and blocks potentially getting allocated more than once if we get really unlucky. Addresses-Google-Bug: 2828254 Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-12-18ext4: do not reference pa_inode from group_paYongqiang Yang
pa_inode in group_pa is set NULL in ext4_mb_new_group_pa, so pa_inode should be not referenced. Reported-by: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Yongqiang Yang <xiaoqiangnk@gmail.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-10-26ext4: fix a wrong comment in __mb_check_buddy()Robin Dong
The comment says the bit should be 0, but the after code assert the bit to be 1. This makes people confused, so fix it. Signed-off-by: Robin Dong <sanbai@taobao.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-10-26ext4: remove unused variable in mb_find_extent()Robin Dong
The variable 'ord' in function mb_find_extent() is redundant, so remove it. Signed-off-by: Robin Dong <sanbai@taobao.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-10-26ext4: remove unused variable in ext4_mb_generate_from_pa()Robin Dong
The variable 'count' in function ext4_mb_generate_from_pa() looks useless, so remove it. Signed-off-by: Robin Dong <sanbai@taobao.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-10-26ext4: use stream-alloc when mb_group_prealloc set to zeroRobin Dong
The kernel will crash on ext4_mb_mark_diskspace_used: BUG_ON(ac->ac_b_ex.fe_len <= 0); after we set /sys/fs/ext4/sda/mb_group_prealloc to zero and create new files in an ext4 filesystem. The reason is: ac_b_ex.fe_len also set to zero(mb_group_prealloc) in ext4_mb_normalize_group_request because the ac_flags contains EXT4_MB_HINT_GROUP_ALLOC. I think when someone set mb_group_prealloc to zero, it means DO NOT USE GROUP PREALLOCATION, so we should set alloc-strategy to STREAM in this case. Signed-off-by: Robin Dong <sanbai@taobao.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-10-21ext4: Allow quota file use root reservationDmitry Monakhov
Quota file is fs's metadata, so it is reasonable to permit use root resevation if necessary. This patch fix 265'th xfstest failure Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-10-06ext4: Free resources in ext4_mb_init()'s error pathsTao Ma
In commit 79a77c5ac, we move ext4_mb_init_backend after the allocation of s_locality_group to avoid memory leak in error path, but there are still some other error paths in ext4_mb_init that need to do the same work. So this patch adds all the error patch for ext4_mb_init. And all the pointers are reset to NULL in case the caller may double free them. Signed-off-by: Tao Ma <boyu.mt@taobao.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-09-09ext4: rename ext4_claim_free_blocks() to ext4_claim_free_clusters()Theodore Ts'o
This function really claims a number of free clusters, not blocks, so rename it so it's clearer what's going on. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-09-09ext4: rename ext4_free_blocks_after_init() to ext4_free_clusters_after_init()Theodore Ts'o
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>
2011-09-09ext4: Rename ext4_free_blks_{count,set}() to refer to clustersTheodore Ts'o
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>
2011-09-09ext4: Fix bigalloc quota accounting and i_blocks valueAditya Kali
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>
2011-09-09ext4: tune mballoc's default group prealloc size for bigalloc file systemsTheodore Ts'o
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>
2011-09-09ext4: convert the free_blocks field in s_flex_groups to be free_clustersTheodore Ts'o
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>
2011-09-09ext4: convert s_{dirty,free}blocks_counter to s_{dirty,free}clusters_counterTheodore Ts'o
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>
2011-09-09ext4: teach ext4_free_blocks() about bigalloc and clustersTheodore Ts'o
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>
2011-09-09ext4: teach mballoc preallocation code about bigalloc clustersTheodore Ts'o
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>
2011-09-09ext4: convert instances of EXT4_BLOCKS_PER_GROUP to EXT4_CLUSTERS_PER_GROUPTheodore Ts'o
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>
2011-08-01ext4: prevent memory leaks from ext4_mb_init_backend() on error pathYu Jian
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>
2011-08-01ext4: use EXT4_BAD_INO for buddy cache to avoid colliding with valid inode #Yu Jian
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>
2011-08-01ext4: use ext4_msg() instead of printk in mballocTheodore Ts'o
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-08-01ext4: use ext4_kvzalloc()/ext4_kvmalloc() for s_group_desc and s_group_infoTheodore Ts'o
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-07-27ext4: let setup_new_group_blocks() set multiple bits at a timeYongqiang Yang
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>
2011-07-27ext4: let ext4_group_add_blocks() handle 0 blocks quicklyYongqiang Yang
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>
2011-07-27ext4: let ext4_group_add_blocks() return an error codeYongqiang Yang
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>
2011-07-27ext4: rename ext4_add_groupblocks() to ext4_group_add_blocks()Yongqiang Yang
Signed-off-by: Yongqiang Yang <xiaoqiangnk@gmail.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-07-23ext4: don't increment s_mb_buddies_generated in ext4_mb_releaseTao Ma
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>
2011-07-23ext4: remove unnecessary ext4_get_group_info in ext4_mb_load_buddyTao Ma
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>
2011-07-18ext4: make the preallocation size be a multiple of stripe sizeDan Ehrenberg
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>
2011-07-11ext4: Fix a double free of sbi->s_group_info in ext4_mb_init_backendTao Ma
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>
2011-07-11ext4: fix a race which could leak memory in ext4_groupinfo_create_slab()Tao Ma
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>
2011-07-11ext4: Change the wrong param comment for ext4_trim_all_freeTao Ma
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>
2011-07-11ext4: Speed up FITRIM by recording flags in ext4_group_infoTao Ma
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>
2011-07-11ext4: Add new ext4 trim tracepointsTao Ma
Add ext4_trim_extent and ext4_trim_all_free. Reviewed-by: Lukas Czerner <lczerner@redhat.com> Signed-off-by: Tao Ma <boyu.mt@taobao.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-07-11ext4: speed up group trim with the right free block countTao Ma
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>
2011-07-11ext4: fix trim length underflow with small trim lengthTao Ma
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>
2011-07-10ext4: fix i_blocks/quota accounting when extent insertion failsMaxim Patlasov
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
2011-06-28ext4: quiet 'unused variables' compile warningsYongqiang Yang
Unused variables was deleted. Signed-off-by: Yongqiang Yang <xiaoqiangnk@gmail.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-06-06ext4: fixed tracepoints cleanupLukas Czerner
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>
2011-06-06ext4: correct comments for ext4_free_blocks()Yongqiang Yang
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>
2011-05-25ext4: add flag to ext4_has_free_blocksAllison Henderson
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>
2011-05-24ext4: protect bb_first_free in ext4_trim_all_free() with group lockLukas Czerner
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>
2011-05-24ext4: only load buddy bitmap in ext4_trim_fs() when it is neededLukas Czerner
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>
2011-05-10ext4: remove alloc_sempAmir Goldstein
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>
2011-05-10ext4: teach ext4_mb_init_cache() to skip uptodate buddy cachesAmir Goldstein
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>
2011-05-10ext4: synchronize ext4_mb_init_group() with buddy page lockAmir Goldstein
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>
2011-05-10ext4: implement ext4_add_groupblocks() by freeing blocksAmir Goldstein
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>