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path: root/fs/ext4/mballoc.c
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2012-11-08ext4: warn when discard request fails other than EOPNOTSUPPLukas Czerner
We should warn user then the discard request fails. However we need to exclude -EOPNOTSUPP case since parts of the device might not support it while other parts can. So print the kernel warning when the error != -EOPNOTSUPP is returned from ext4_issue_discard(). We should also handle error cases in batched discard, again excluding EOPNOTSUPP. Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com> Signed-off-by: Lukas Czerner <lczerner@redhat.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-11-08ext4: remove unused assignmentAlan Cox
Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-11-08ext4: fix awful goto in ext4_mb_new_blocks()Eric Sandeen
I think the whole function could be made prettier, but that goto really took the cake for too-clever-by-half. Signed-off-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-10-23Merge tag 'ext4_for_linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 Pull ext4 fixes from Ted Ts'o: "Various bug fixes for ext4. The most serious of them fixes a security bug (CVE-2012-4508) which leads to stale data exposure when we have fallocate racing against writes to files undergoing delayed allocation. We also have two fixes for the metadata checksum feature, the most serious of which can cause the superblock to have a invalid checksum after a power failure." * tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: ext4: Avoid underflow in ext4_trim_fs() ext4: Checksum the block bitmap properly with bigalloc enabled ext4: fix undefined bit shift result in ext4_fill_flex_info ext4: fix metadata checksum calculation for the superblock ext4: race-condition protection for ext4_convert_unwritten_extents_endio ext4: serialize fallocate with ext4_convert_unwritten_extents
2012-10-22ext4: Avoid underflow in ext4_trim_fs()Lukas Czerner
Currently if len argument in ext4_trim_fs() is smaller than one block, the 'end' variable underflow. Avoid that by returning EINVAL if len is smaller than file system block. Also remove useless unlikely(). Signed-off-by: Lukas Czerner <lczerner@redhat.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Cc: stable@vger.kernel.org
2012-10-22ext4: Checksum the block bitmap properly with bigalloc enabledTao Ma
In mke2fs, we only checksum the whole bitmap block and it is right. While in the kernel, we use EXT4_BLOCKS_PER_GROUP to indicate the size of the checksumed bitmap which is wrong when we enable bigalloc. The right size should be EXT4_CLUSTERS_PER_GROUP and this patch fixes it. Also as every caller of ext4_block_bitmap_csum_set and ext4_block_bitmap_csum_verify pass in EXT4_BLOCKS_PER_GROUP(sb)/8, we'd better removes this parameter and sets it in the function itself. Signed-off-by: Tao Ma <boyu.mt@taobao.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Reviewed-by: Lukas Czerner <lczerner@redhat.com> Cc: stable@vger.kernel.org
2012-10-08Merge tag 'ext4_for_linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 Pull ext4 updates from Ted Ts'o: "The big new feature added this time is supporting online resizing using the meta_bg feature. This allows us to resize file systems which are greater than 16TB. In addition, the speed of online resizing has been improved in general. We also fix a number of races, some of which could lead to deadlocks, in ext4's Asynchronous I/O and online defrag support, thanks to good work by Dmitry Monakhov. There are also a large number of more minor bug fixes and cleanups from a number of other ext4 contributors, quite of few of which have submitted fixes for the first time." * tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (69 commits) ext4: fix ext4_flush_completed_IO wait semantics ext4: fix mtime update in nodelalloc mode ext4: fix ext_remove_space for punch_hole case ext4: punch_hole should wait for DIO writers ext4: serialize truncate with owerwrite DIO workers ext4: endless truncate due to nonlocked dio readers ext4: serialize unlocked dio reads with truncate ext4: serialize dio nonlocked reads with defrag workers ext4: completed_io locking cleanup ext4: fix unwritten counter leakage ext4: give i_aiodio_unwritten a more appropriate name ext4: ext4_inode_info diet ext4: convert to use leXX_add_cpu() ext4: ext4_bread usage audit fs: reserve fallocate flag codepoint ext4: remove redundant offset check in mext_check_arguments() ext4: don't clear orphan list on ro mount with errors jbd2: fix assertion failure in commit code due to lacking transaction credits ext4: release donor reference when EXT4_IOC_MOVE_EXT ioctl fails ext4: enable FITRIM ioctl on bigalloc file system ...
2012-10-01Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial Pull the trivial tree from Jiri Kosina: "Tiny usual fixes all over the place" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (34 commits) doc: fix old config name of kprobetrace fs/fs-writeback.c: cleanup riteback_sb_inodes kerneldoc btrfs: fix the commment for the action flags in delayed-ref.h btrfs: fix trivial typo for the comment of BTRFS_FREE_INO_OBJECTID vfs: fix kerneldoc for generic_fh_to_parent() treewide: fix comment/printk/variable typos ipr: fix small coding style issues doc: fix broken utf8 encoding nfs: comment fix platform/x86: fix asus_laptop.wled_type module parameter mfd: printk/comment fixes doc: getdelays.c: remember to close() socket on error in create_nl_socket() doc: aliasing-test: close fd on write error mmc: fix comment typos dma: fix comments spi: fix comment/printk typos in spi Coccinelle: fix typo in memdup_user.cocci tmiofb: missing NULL pointer checks tools: perf: Fix typo in tools/perf tools/testing: fix comment / output typos ...
2012-09-26ext4: enable FITRIM ioctl on bigalloc file systemLukas Czerner
With a minor tweaks regarding minimum extent size to discard and discarded bytes reporting the FITRIM can be enabled on bigalloc file system and it works without any problem. This patch fixes minlen handling and discarded bytes reporting to take into consideration bigalloc enabled file systems and finally removes the restriction and allow FITRIM to be used on file system with bigalloc feature enabled. Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com> Signed-off-by: Lukas Czerner <lczerner@redhat.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-09-26ext4: use kmem_cache_zalloc instead of kmem_cache_alloc/memsetWei Yongjun
Using kmem_cache_zalloc() instead of kmem_cache_alloc() and memset(). spatch with a semantic match is used to found this problem. (http://coccinelle.lip6.fr/) Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-09-23ext4: check free block counters in ext4_mb_find_by_goalYongqiang Yang
Free block counters should be checked before doing allocation. Signed-off-by: Yongqiang Yang <xiaoqiangnk@gmail.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-09-18ext4: re-enable -o discard functionality in no-journal modeTheodore Ts'o
This is a revert of commit b56ff9d397ce, which removed the call to ext4_issue_discard() to fix a BUG reported because ext4_issue_discard() was being called from inside a block group spinlock. As it turns out this bug had already been fixed by Lukas Czerner in commit 53fdcf992d61 by the simple expedient of moving when we call ext4_issue_discard() outside the spinlock. So it should be safe to re-enable this functionality, which I tested by putting an BUG_ON(in_atomic) just after the restored callsite to ext4_issue_discard(). Addresses-Google-Bug: #6750518 Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Cc: Anatol Pomozov <anatol.pomozov@gmail.com>
2012-09-05ext4: grow the s_group_info array as neededTheodore Ts'o
Previously we allocated the s_group_info array with enough space for any future possible growth of the file system via online resize. This is unfortunate because it wastes memory, and it doesn't work for the meta_bg scheme, since there is no limit based on the number of reserved gdt blocks. So add the code to grow the s_group_info array as needed. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-09-01treewide: fix comment/printk/variable typosAnatol Pomozov
Signed-off-by: Anatol Pomozov <anatol.pomozov@gmail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2012-08-17ext4: remove unused function argument 'order' in mb_find_extent()Robin Dong
All the routines call mb_find_extent are setting argument 'order' to 0 just like: mb_find_extent(e4b, 0, ex.fe_start, ex.fe_len, &ex); therefore the useless argument should be removed. Signed-off-by: Robin Dong <sanbai@taobao.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-08-17ext4: don't load the block bitmap for block groups which have no spaceTheodore Ts'o
Add a short circuit check to ext4_mb_group_group() so that we don't bother to load the block bitmap for a block group which does not have any space available. (Or which does not have enough space until we are in desperation mode, i.e., when cr == 3.) Resolves-bug: https://bugzilla.kernel.org/show_bug.cgi?id=45741 Reported-by: mirek@me.com Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-07-22ext4: remove useless marking of superblock dirtyJan Kara
Commit a0375156 properly notes that superblock doesn't need to be marked as dirty when only number of free inodes / blocks / number of directories changes since that is recomputed on each mount anyway. However that comment leaves some unnecessary markings as dirty in place. Remove these. Artem: tested using xfstests for both journalled and non-journalled ext4. Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Tested-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
2012-07-09ext4: remove an unused statement in ext4_mb_get_buddy_page_lock()Haibo Liu
In this patch, the statement "poff = block % blocks_per_page" in ext4_mb_get_buddy_page_lock has no effect. It will be optimized out by the compiler, but it's better to remove it. Signed-off-by: Haibo Liu <HaiboLiu6@gmail.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-06-30ext4: avoid uneeded calls to ext4_mb_load_buddy() while reading mb_groupsAditya Kali
Currently ext4_mb_load_buddy is called for every group, irrespective of whether the group info is already in memory, while reading /proc/fs/ext4/<partition>/mb_groups proc file. For the purpose of mb_groups proc file, it is unnecessary to load the file group info from disk if it was loaded in past. These calls to ext4_mb_load_buddy make reading the mb_groups proc file expensive. Also, the locks around ext4_get_group_info are not required. This patch modifies the code to call ext4_mb_load_buddy only if the group info had never been loaded into memory in past. It also removes the mb group locking around ext4_get_group_info call. Signed-off-by: Aditya Kali <adityakali@google.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-05-31ext4: remove mb_groups before tearing down the buddy_cacheSalman Qazi
We can't have references held on pages in the s_buddy_cache while we are trying to truncate its pages and put the inode. All the pages must be gone before we reach clear_inode. This can only be gauranteed if we can prevent new users from grabbing references to s_buddy_cache's pages. The original bug can be reproduced and the bug fix can be verified by: while true; do mount -t ext4 /dev/ram0 /export/hda3/ram0; \ umount /export/hda3/ram0; done & while true; do cat /proc/fs/ext4/ram0/mb_groups; done Signed-off-by: Salman Qazi <sqazi@google.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Cc: stable@kernel.org
2012-05-31ext4: add ext4_mb_unload_buddy in the error pathSalman Qazi
ext4_free_blocks fails to pair an ext4_mb_load_buddy with a matching ext4_mb_unload_buddy when it fails a memory allocation. Signed-off-by: Salman Qazi <sqazi@google.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Cc: stable@kernel.org
2012-05-28ext4: cleanup in ext4_discard_allocated_blocks()Zheng Liu
remove 'len' variable in ext4_discard_allocated_blocks() because it is useless. Signed-off-by: Zheng Liu <wenqing.lz@taobao.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-05-28ext4: remove needs_recovery in ext4_mb_init()Akira Fujita
needs_recovery in ext4_mb_init() is not used, remove it. Signed-off-by: Akira Fujita <a-fujita@rs.jp.ne.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-04-29ext4: make block group checksums use metadata_csum algorithmDarrick J. Wong
metadata_csum supersedes uninit_bg. Convert the ROCOMPAT uninit_bg flag check to a helper function that covers both, and make the checksum calculation algorithm use either crc16 or the metadata_csum chosen algorithm depending on which flag is set. Print a warning if we try to mount a filesystem with both feature flags set. Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-04-29ext4: calculate and verify block bitmap checksumDarrick J. Wong
Compute and verify the checksum of the block bitmap; this checksum is stored in the block group descriptor. Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-03-21ext4: always set then trimmed blocks count into lenLukas Czerner
Currently if the range to trim is too small, for example on 1K fs the request to trim the first block, then the 'range->len' is not set reporting wrong number of discarded block to the caller. Fix this by always setting the 'range->len' before we return. Note that when there is a failure (-EINVAL) caller can not depend on 'range->len' being set properly. Signed-off-by: Lukas Czerner <lczerner@redhat.com> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-03-21ext4: fix trimmed block count accuntingLukas Czerner
Currently when there is not enough free blocks in the block group to discard (grp->bb_free < minlen) the 'trimmed' is bumped up anyway with the number of discarded blocks from the previous iteration. Fix this by bumping up 'trimmed' only if the ext4_trim_all_free() was actually run. Signed-off-by: Lukas Czerner <lczerner@redhat.com> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-03-21ext4: fix start and len arguments handling in ext4_trim_fs()Lukas Czerner
The overflow can happen when we are calling get_group_no_and_offset() which stores the group number in the ext4_grpblk_t type which is actually int. However when the blocknr is big enough the group number might be bigger than ext4_grpblk_t resulting in overflow. This will most likely happen with FITRIM default argument len = ULLONG_MAX. Fix this by using "end" variable instead of "start+len" as it is easier to get right and specifically check that the end is not beyond the end of the file system, so we are sure that the result of get_group_no_and_offset() will not overflow. Otherwise truncate it to the size of the file system. Signed-off-by: Lukas Czerner <lczerner@redhat.com> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-03-19ext4: remove trailing newlines from ext4_msg() and ext4_error() messagesTheodore Ts'o
The functions ext4_msg() and ext4_error() already tack on a trailing newline, so remove the unnecessary extra newline. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-03-19ext4: remove redundant "EXT4-fs: " from uses of ext4_msgJoe Perches
ext4_msg adds "EXT4-fs: " to the messsage output. Remove the redundant bits from uses. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
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>
2011-10-20ext4: 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>