summaryrefslogtreecommitdiffstats
path: root/fs/ext4/balloc.c
AgeCommit message (Collapse)Author
2013-03-02ext4: convert number of blocks to clusters properlyLukas Czerner
We're using macro EXT4_B2C() to convert number of blocks to number of clusters for bigalloc file systems. However, we should be using EXT4_NUM_B2C(). Signed-off-by: Lukas Czerner <lczerner@redhat.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Cc: stable@vger.kernel.org
2013-02-22ext4: fix free clusters calculation in bigalloc filesystemLukas Czerner
ext4_has_free_clusters() should tell us whether there is enough free clusters to allocate, however number of free clusters in the file system is converted to blocks using EXT4_C2B() which is not only wrong use of the macro (we should have used EXT4_NUM_B2C) but it's also completely wrong concept since everything else is in cluster units. Moreover when calculating number of root clusters we should be using macro EXT4_NUM_B2C() instead of EXT4_B2C() otherwise the result might be off by one. However r_blocks_count should always be a multiple of the cluster ratio so doing a plain bit shift should be enough here. We avoid using EXT4_B2C() because it's confusing. As a result of the first problem number of free clusters is much bigger than it should have been and ext4_has_free_clusters() would return 1 even if there is really not enough free clusters available. Fix this by removing the EXT4_C2B() conversion of free clusters and using bit shift when calculating number of root clusters. This bug affects number of xfstests tests covering file system ENOSPC situation handling. With this patch most of the ENOSPC problems with bigalloc file system disappear, especially the errors caused by delayed allocation not having enough space when the actual allocation is finally requested. Signed-off-by: Lukas Czerner <lczerner@redhat.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Cc: stable@vger.kernel.org
2013-01-12ext4: check bh in ext4_read_block_bitmap()Eryu Guan
Validate the bh pointer before using it, since ext4_read_block_bitmap_nowait() might return NULL. I've seen this in fsfuzz testing. EXT4-fs error (device loop0): ext4_read_block_bitmap_nowait:385: comm touch: Cannot get buffer for block bitmap - block_group = 0, block_bitmap = 3925999616 BUG: unable to handle kernel NULL pointer dereference at (null) IP: [<ffffffff8121de25>] ext4_wait_block_bitmap+0x25/0xe0 ... Call Trace: [<ffffffff8121e1e5>] ext4_read_block_bitmap+0x35/0x60 [<ffffffff8125e9c6>] ext4_free_blocks+0x236/0xb80 [<ffffffff811d0d36>] ? __getblk+0x36/0x70 [<ffffffff811d0a5f>] ? __find_get_block+0x8f/0x210 [<ffffffff81191ef3>] ? kmem_cache_free+0x33/0x140 [<ffffffff812678e5>] ext4_xattr_release_block+0x1b5/0x1d0 [<ffffffff812679be>] ext4_xattr_delete_inode+0xbe/0x100 [<ffffffff81222a7c>] ext4_free_inode+0x7c/0x4d0 [<ffffffff812277b8>] ? ext4_mark_inode_dirty+0x88/0x230 [<ffffffff8122993c>] ext4_evict_inode+0x32c/0x490 [<ffffffff811b8cd7>] evict+0xa7/0x1c0 [<ffffffff811b8ed3>] iput_final+0xe3/0x170 [<ffffffff811b8f9e>] iput+0x3e/0x50 [<ffffffff812316fd>] ext4_add_nondir+0x4d/0x90 [<ffffffff81231d0b>] ext4_create+0xeb/0x170 [<ffffffff811aae9c>] vfs_create+0xac/0xd0 [<ffffffff811ac845>] lookup_open+0x185/0x1c0 [<ffffffff8129e3b9>] ? selinux_inode_permission+0xa9/0x170 [<ffffffff811acb54>] do_last+0x2d4/0x7a0 [<ffffffff811af743>] path_openat+0xb3/0x480 [<ffffffff8116a8a1>] ? handle_mm_fault+0x251/0x3b0 [<ffffffff811afc49>] do_filp_open+0x49/0xa0 [<ffffffff811bbaad>] ? __alloc_fd+0xdd/0x150 [<ffffffff8119da28>] do_sys_open+0x108/0x1f0 [<ffffffff8119db51>] sys_open+0x21/0x30 [<ffffffff81618959>] system_call_fastpath+0x16/0x1b Also fix comment for ext4_read_block_bitmap_nowait() Signed-off-by: Eryu Guan <guaneryu@gmail.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
2012-08-17ext4: don't call ext4_error while block group is lockedTheodore Ts'o
While in ext4_validate_block_bitmap(), if an block allocation bitmap is found to be invalid, we call ext4_error() while the block group is still locked. This causes ext4_commit_super() to call a function which might sleep while in an atomic context. There's no need to keep the block group locked at this point, so hoist the ext4_error() call up to ext4_validate_block_bitmap() and release the block group spinlock before calling ext4_error(). The reported stack trace can be found at: http://article.gmane.org/gmane.comp.file-systems.ext4/33731 Reported-by: Dave Jones <davej@redhat.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Cc: stable@vger.kernel.org
2012-06-30ext4: pass a char * to ext4_count_free() instead of a buffer_head ptrTheodore Ts'o
Make it possible for ext4_count_free to operate on buffers and not just data in buffer_heads. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Cc: stable@kernel.org
2012-06-07ext4: fix the free blocks calculation for ext3 file systems w/ uninit_bgTheodore Ts'o
Ext3 filesystems that are converted to use as many ext4 file system features as possible will enable uninit_bg to speed up e2fsck times. These file systems will have a native ext3 layout of inode tables and block allocation bitmaps (as opposed to ext4's flex_bg layout). Unfortunately, in these cases, when first allocating a block in an uninitialized block group, ext4 would incorrectly calculate the number of free blocks in that block group, and then errorneously report that the file system was corrupt: EXT4-fs error (device vdd): ext4_mb_generate_buddy:741: group 30, 32254 clusters in bitmap, 32258 in gd This problem can be reproduced via: mke2fs -q -t ext4 -O ^flex_bg /dev/vdd 5g mount -t ext4 /dev/vdd /mnt fallocate -l 4600m /mnt/test The problem was caused by a bone headed mistake in the check to see if a particular metadata block was part of the block group. Many thanks to Kees Cook for finding and bisecting the buggy commit which introduced this bug (commit fd034a84e1, present since v3.2). Reported-by: Sander Eikelenboom <linux@eikelenboom.it> Reported-by: Kees Cook <keescook@chromium.org> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Tested-by: Kees Cook <keescook@chromium.org> Cc: stable@kernel.org
2012-06-01Merge tag 'ext4_for_linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 Pull Ext4 updates from Theodore Ts'o: "The major new feature added in this update is Darrick J Wong's metadata checksum feature, which adds crc32 checksums to ext4's metadata fields. There is also the usual set of cleanups and bug fixes." * tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (44 commits) ext4: hole-punch use truncate_pagecache_range jbd2: use kmem_cache_zalloc wrapper instead of flag ext4: remove mb_groups before tearing down the buddy_cache ext4: add ext4_mb_unload_buddy in the error path ext4: don't trash state flags in EXT4_IOC_SETFLAGS ext4: let getattr report the right blocks in delalloc+bigalloc ext4: add missing save_error_info() to ext4_error() ext4: add debugging trigger for ext4_error() ext4: protect group inode free counting with group lock ext4: use consistent ssize_t type in ext4_file_write() ext4: fix format flag in ext4_ext_binsearch_idx() ext4: cleanup in ext4_discard_allocated_blocks() ext4: return ENOMEM when mounts fail due to lack of memory ext4: remove redundundant "(char *) bh->b_data" casts ext4: disallow hard-linked directory in ext4_lookup ext4: fix potential integer overflow in alloc_flex_gd() ext4: remove needs_recovery in ext4_mb_init() ext4: force ro mount if ext4_setup_super() fails ext4: fix potential NULL dereference in ext4_free_inodes_counts() ext4/jbd2: add metadata checksumming to the list of supported features ...
2012-05-15userns: Convert ext4 to user kuid/kgid where appropriateEric W. Biederman
Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
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>
2012-02-20ext4: fix balloc.c printk-format-warningHeiko Carstens
Get rid of this one: fs/ext4/balloc.c: In function 'ext4_wait_block_bitmap': fs/ext4/balloc.c:405:3: warning: format '%llu' expects argument of type 'long long unsigned int', but argument 6 has type 'sector_t' [-Wformat] Happens because sector_t is u64 (unsigned long long) or unsigned long dependent on CONFIG_64BIT. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Acked-by: Randy Dunlap <rdunlap@xenotime.net> 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>
2012-01-04ext4: make more symbols staticEric Sandeen
A couple more functions can reasonably be made static if desired. Signed-off-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-11-21ext4: fix up a undefined error in ext4_free_blocks in debugging codeYongqiang Yang
sbi is not defined, so let ext4_free_blocks use EXT4_SB(sb) instead when EXT4FS_DEBUG is defined. Signed-off-by: Yongqiang Yang <xiaoqiangnk@gmail.com>
2011-09-09ext4: rename ext4_has_free_blocks() to ext4_has_free_clusters()Theodore Ts'o
Rename the function so it is more clear what is going on. Also rename the various variables so it's clearer what's happening. Also fix a missing blocks to cluster conversion when reading the number of reserved blocks for root. 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_count_free_blocks() to ext4_count_free_clusters()Theodore Ts'o
This function really counts the free clusters reported in the block group descriptors, so rename it to reduce confusion. 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: 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: convert block group-relative offsets to use clustersTheodore Ts'o
Certain parts of the ext4 code base, primarily in mballoc.c, use a block group number and offset from the beginning of the block group. This offset is invariably used to index into the allocation bitmap, so change the offset to be denominated in units of clusters. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-09-09ext4: bigalloc changes to block bitmap initialization functionsTheodore Ts'o
Add bigalloc support to ext4_init_block_bitmap() and ext4_free_blocks_after_init(). Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-09-09ext4: split out ext4_free_blocks_after_init()Theodore Ts'o
The function ext4_free_blocks_after_init() used to be a #define of ext4_init_block_bitmap(). This actually made it difficult to understand how the function worked, and made it hard make changes to support clusters. So as an initial cleanup, I've separated out the functionality of initializing block bitmap from calculating the number of free blocks in the new block group. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-09-09ext4: factor out block group accounting into functionsTheodore Ts'o
This makes it easier to understand how ext4_init_block_bitmap() works, and it will assist when we split out ext4_free_blocks_after_init() in the next commit. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-06-28ext4: refactor duplicated block placement codeEric Sandeen
I found that ext4_ext_find_goal() and ext4_find_near() share the same code for returning a coloured start block based on i_block_group. We can refactor this into a common function so that they don't diverge in the future. Thanks to adilger for suggesting the new function name. Signed-off-by: Eric Sandeen <sandeen@redhat.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>
2011-05-09ext4: move ext4_add_groupblocks() to mballoc.cAmir Goldstein
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>
2011-05-01ext4: remove dead code in ext4_has_free_blocks()Shaohua Li
percpu_counter_sum_positive() never returns a negative value. Signed-off-by: Shaohua Li <shaohua.li@intel.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-03-31Fix common misspellingsLucas De Marchi
Fixes generated by 'codespell' and manually reviewed. Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2011-03-21ext4: add more tracepoints and use dev_t in the trace bufferJiaying Zhang
- Add more ext4 tracepoints. - Change ext4 tracepoints to use dev_t field with MAJOR/MINOR macros so that we can save 4 bytes in the ring buffer on some platforms. - Add sync_mode to ext4_da_writepages, ext4_da_write_pages, and ext4_da_writepages_result tracepoints. Also remove for_reclaim field from ext4_da_writepages since it is usually not very useful. Signed-off-by: Jiaying Zhang <jiayingz@google.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-01-10ext4: replace i_delalloc_reserved_flag with EXT4_STATE_DELALLOC_RESERVEDTheodore Ts'o
Remove the short element i_delalloc_reserved_flag from the ext4_inode_info structure and replace it a new bit in i_state_flags. Since we have an ext4_inode_info for every ext4 inode cached in the inode cache, any savings we can produce here is a very good thing from a memory utilization perspective. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-10-27ext4: rename mark_bitmap_end() to ext4_mark_bitmap_end()Theodore Ts'o
Fix a namespace leak from fs/ext4 Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-10-27ext4: make various ext4 functions be staticTheodore Ts'o
These functions have no need to be exported beyond file context. No functions needed to be moved for this commit; just some function declarations changed to be static and removed from header files. (A similar patch was submitted by Eric Sandeen, but I wanted to handle code movement in separate patches to make sure code changes didn't accidentally get dropped.) Signed-off-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-06-11ext4: Clean up s_dirt handlingTheodore Ts'o
We don't need to set s_dirt in most of the ext4 code when journaling is enabled. In ext3/4 some of the summary statistics for # of free inodes, blocks, and directories are calculated from the per-block group statistics when the file system is mounted or unmounted. As a result the superblock doesn't have to be updated, either via the journal or by setting s_dirt. There are a few exceptions, most notably when resizing the file system, where the superblock needs to be modified --- and in that case it should be done as a journalled operation if possible, and s_dirt set only in no-journal mode. This patch will optimize out some unneeded disk writes when using ext4 with a journal. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-05-16ext4: don't use quota reservation for speculative metadataEric Sandeen
Because we can badly over-reserve metadata when we calculate worst-case, it complicates things for quota, since we must reserve and then claim later, retry on EDQUOT, etc. Quota is also a generally smaller pool than fs free blocks, so this over-reservation hurts more, and more often. I'm of the opinion that it's not the worst thing to allow metadata to push a user slightly over quota. This simplifies the code and avoids the false quota rejections that result from worst-case speculation. This patch stops the speculative quota-charging for worst-case metadata requirements, and just charges quota when the blocks are allocated at writeout. It also is able to remove the try-again loop on EDQUOT. This patch has been tested indirectly by running the xfstests suite with a hack to mount & enable quota prior to the test. I also did a more specific test of fragmenting freespace and then doing a large delalloc write under quota; quota stopped me at the right amount of file IO, and then the writeout generated enough metadata (due to the fragmentation) that it put me slightly over quota, as expected. Signed-off-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2010-03-03ext4: consolidate in_range() definitionsAkinobu Mita
There are duplicate macro definitions of in_range() in mballoc.h and balloc.c. This consolidates these two definitions into ext4.h, and changes extents.c to use in_range() as well. Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Cc: Andreas Dilger <adilger@sun.com>
2010-03-03ext4: cleanup to use ext4_group_first_block_no()Akinobu Mita
This is a cleanup and simplification patch which takes some open-coded calculations to calculate the first block number of a group and converts them to use the (already defined) ext4_group_first_block_no() function. Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Cc: Andreas Dilger <adilger@sun.com>
2010-02-15ext4: move __func__ into a macro for ext4_warning, ext4_errorEric Sandeen
Just a pet peeve of mine; we had a mishash of calls with either __func__ or "function_name" and the latter tends to get out of sync. I think it's easier to just hide the __func__ in a macro, and it'll be consistent from then on. Signed-off-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-11-22ext4: fold ext4_free_blocks() and ext4_mb_free_blocks()Theodore Ts'o
ext4_mb_free_blocks() is only called by ext4_free_blocks(), and the latter function doesn't really do much. So merge the two functions together, such that ext4_free_blocks() is now found in fs/ext4/mballoc.c. This saves about 200 bytes of compiled text space. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-11-23ext4: fix uninit block bitmap initialization when s_meta_first_bg is non-zeroTheodore Ts'o
The number of old-style block group descriptor blocks is s_meta_first_bg when the meta_bg feature flag is set. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Cc: stable@kernel.org
2009-08-17ext4: open-code ext4_mb_update_group_infoEric Sandeen
ext4_mb_update_group_info is only called in one place, and it's extremely simple. There's no reason to have it in a separate function in a separate file as far as I can tell, it just obfuscates what's really going on. Perhaps it was intended to keep the grp->bb_* manipulation local to mballoc.c but we're already accessing other grp-> fields in balloc.c directly so this seems ok. Signed-off-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-05-02ext4: Convert ext4_lock_group to use sb_bgl_lockAneesh Kumar K.V
We have sb_bgl_lock() and ext4_group_info.bb_state bit spinlock to protech group information. The later is only used within mballoc code. Consolidate them to use sb_bgl_lock(). This makes the mballoc.c code much simpler and also avoid confusion with two locks protecting same info. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-05-01ext4: Move fs/ext4/group.h into ext4.hTheodore Ts'o
Move the function prototypes in group.h into ext4.h so they are all defined in one place. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-05-01ext4: Avoid races caused by on-line resizing and SMP memory reorderingTheodore Ts'o
Ext4's on-line resizing adds a new block group and then, only at the last step adjusts s_groups_count. However, it's possible on SMP systems that another CPU could see the updated the s_group_count and not see the newly initialized data structures for the just-added block group. For this reason, it's important to insert a SMP read barrier after reading s_groups_count and before reading any (for example) the new block group descriptors allowed by the increased value of s_groups_count. Unfortunately, we rather blatently violate this locking protocol documented in fs/ext4/resize.c. Fortunately, (1) on-line resizes happen relatively rarely, and (2) it seems rare that the filesystem code will immediately try to use just-added block group before any memory ordering issues resolve themselves. So apparently problems here are relatively hard to hit, since ext3 has been vulnerable to the same issue for years with no one apparently complaining. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-03-04ext4: Use atomic_t's in struct flex_groupsTheodore Ts'o
Reduce pressure on the sb_bgl_lock family of locks by using atomic_t's to track the number of free blocks and inodes in each flex_group. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-02-06ext4: remove call to ext4_group_desc() in ext4_group_used_meta_blocks()Theodore Ts'o
The static function ext4_group_used_meta_blocks() only has one caller, who already has access to the block group's group descriptor. So it's better to have ext4_init_block_bitmap() pass the group descriptor to ext4_group_used_meta_blocks(), so it doesn't need to call ext4_group_desc(). Previously this function did not check if ext4_group_desc() returned NULL due to an error, potentially causing a kernel OOPS report. This avoids the issue entirely. Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@holoscopio.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-03-26ext4: Use lowercase names of quota functionsJan Kara
Use lowercase names of quota functions instead of old uppercase ones. Signed-off-by: Jan Kara <jack@suse.cz> Acked-by: Mingming Cao <cmm@us.ibm.com> CC: linux-ext4@vger.kernel.org
2009-02-26ext4: don't call jbd2_journal_force_commit_nested without journalEric Sandeen
Running without a journal, I oopsed when I ran out of space, because we called jbd2_journal_force_commit_nested() from ext4_should_retry_alloc() without a journal. This should take care of it, I think. Signed-off-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>