kernel.git/fs/ext4/resize.c, branch linux-2.6.24.y

ext4: lighten up resize transaction requirements

2007-10-17T22:50:04Z

When resizing online, setup_new_group_blocks attempts to reserve a potentially very large transaction, depending on the current filesystem geometry. For some journal sizes, there may not be enough room for this transaction, and the online resize will fail. The patch below resizes & restarts the transaction as necessary while setting up the new group, and should work with even the smallest journal. Tested with something like: [root@newbox ~]# dd if=/dev/zero of=fsfile bs=1024 count=32768 [root@newbox ~]# mkfs.ext3 -b 1024 fsfile 16384 [root@newbox ~]# mount -o loop fsfile mnt/ [root@newbox ~]# resize2fs /dev/loop0 resize2fs 1.40.2 (12-Jul-2007) Filesystem at /dev/loop0 is mounted on /root/mnt; on-line resizing required old desc_blocks = 1, new_desc_blocks = 1 Performing an on-line resize of /dev/loop0 to 32768 (1k) blocks. resize2fs: No space left on device While trying to add group #2 [root@newbox ~]# dmesg | tail -n 1 JBD: resize2fs wants too many credits (258 > 256) [root@newbox ~]# With the below change, it works. Signed-off-by: Eric Sandeen Signed-off-by: Mingming Cao Acked-by: Andreas Dilger

ext4: fix setup_new_group_blocks locking

2007-10-17T22:50:04Z

setup_new_group_blocks() manipulates the group descriptor block bh under the block_bitmap bh's lock. It shouldn't matter since nobody but resize should be touching these blocks, but it's worth fixing up. Signed-off-by: Eric Sandeen Signed-off-by: Mingming Cao

Ext4: Uninitialized Block Groups

2007-10-17T22:50:00Z

In pass1 of e2fsck, every inode table in the fileystem is scanned and checked, regardless of whether it is in use. This is this the most time consuming part of the filesystem check. The unintialized block group feature can greatly reduce e2fsck time by eliminating checking of uninitialized inodes. With this feature, there is a a high water mark of used inodes for each block group. Block and inode bitmaps can be uninitialized on disk via a flag in the group descriptor to avoid reading or scanning them at e2fsck time. A checksum of each group descriptor is used to ensure that corruption in the group descriptor's bit flags does not cause incorrect operation. The feature is enabled through a mkfs option mke2fs /dev/ -O uninit_groups A patch adding support for uninitialized block groups to e2fsprogs tools has been posted to the linux-ext4 mailing list. The patches have been stress tested with fsstress and fsx. In performance tests testing e2fsck time, we have seen that e2fsck time on ext3 grows linearly with the total number of inodes in the filesytem. In ext4 with the uninitialized block groups feature, the e2fsck time is constant, based solely on the number of used inodes rather than the total inode count. Since typical ext4 filesystems only use 1-10% of their inodes, this feature can greatly reduce e2fsck time for users. With performance improvement of 2-20 times, depending on how full the filesystem is. The attached graph shows the major improvements in e2fsck times in filesystems with a large total inode count, but few inodes in use. In each group descriptor if we have EXT4_BG_INODE_UNINIT set in bg_flags: Inode table is not initialized/used in this group. So we can skip the consistency check during fsck. EXT4_BG_BLOCK_UNINIT set in bg_flags: No block in the group is used. So we can skip the block bitmap verification for this group. We also add two new fields to group descriptor as a part of uninitialized group patch. __le16 bg_itable_unused; /* Unused inodes count */ __le16 bg_checksum; /* crc16(sb_uuid+group+desc) */ bg_itable_unused: If we have EXT4_BG_INODE_UNINIT not set in bg_flags then bg_itable_unused will give the offset within the inode table till the inodes are used. This can be used by fsck to skip list of inodes that are marked unused. bg_checksum: Now that we depend on bg_flags and bg_itable_unused to determine the block and inode usage, we need to make sure group descriptor is not corrupt. We add checksum to group descriptor to detect corruption. If the descriptor is found to be corrupt, we mark all the blocks and inodes in the group used. Signed-off-by: Avantika Mathur Signed-off-by: Andreas Dilger Signed-off-by: Mingming Cao Signed-off-by: Aneesh Kumar K.V

lib: percpu_counter_add

2007-10-17T15:42:44Z

s/percpu_counter_mod/percpu_counter_add/ Because its a better name, _mod implies modulo. Signed-off-by: Peter Zijlstra Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

header cleaning: don't include smp_lock.h when not used

2007-05-08T18:15:07Z

Remove includes of where it is not used/needed. Suggested by Al Viro. Builds cleanly on x86_64, i386, alpha, ia64, powerpc, sparc, sparc64, and arm (all 59 defconfigs). Signed-off-by: Randy Dunlap Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] remove many unneeded #includes of sched.h

2007-02-14T16:09:54Z

After Al Viro (finally) succeeded in removing the sched.h #include in module.h recently, it makes sense again to remove other superfluous sched.h includes. There are quite a lot of files which include it but don't actually need anything defined in there. Presumably these includes were once needed for macros that used to live in sched.h, but moved to other header files in the course of cleaning it up. To ease the pain, this time I did not fiddle with any header files and only removed #includes from .c-files, which tend to cause less trouble. Compile tested against 2.6.20-rc2 and 2.6.20-rc2-mm2 (with offsets) on alpha, arm, i386, ia64, mips, powerpc, and x86_64 with allnoconfig, defconfig, allmodconfig, and allyesconfig as well as a few randconfigs on x86_64 and all configs in arch/arm/configs on arm. I also checked that no new warnings were introduced by the patch (actually, some warnings are removed that were emitted by unnecessarily included header files). Signed-off-by: Tim Schmielau Acked-by: Russell King Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] ext4: fix printk format warnings

2006-10-28T18:30:51Z

fs/ext4/resize.c:72: warning: long long unsigned int format, __u64 arg (arg 4) fs/ext4/resize.c:76: warning: long long unsigned int format, __u64 arg (arg 4) fs/ext4/resize.c:81: warning: long long unsigned int format, __u64 arg (arg 4) fs/ext4/resize.c:85: warning: long long unsigned int format, __u64 arg (arg 4) fs/ext4/resize.c:89: warning: long long unsigned int format, __u64 arg (arg 4) fs/ext4/resize.c:89: warning: long long unsigned int format, __u64 arg (arg 5) fs/ext4/resize.c:93: warning: long long unsigned int format, __u64 arg (arg 4) fs/ext4/resize.c:93: warning: long long unsigned int format, __u64 arg (arg 5) fs/ext4/resize.c:98: warning: long long unsigned int format, __u64 arg (arg 4) fs/ext4/resize.c:103: warning: long long unsigned int format, __u64 arg (arg 4) fs/ext4/resize.c:109: warning: long long unsigned int format, __u64 arg (arg 4) Signed-off-by: Randy Dunlap Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] ext4: move block number hi bits

2006-10-11T18:14:18Z

move '_hi' bits of block numbers in the larger part of the block group descriptor structure Signed-off-by: Alexandre Ratchov Signed-off-by: Dave Kleikamp Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] ext4: blk_type from sector_t to unsigned long long

2006-10-11T18:14:18Z

Change ext4 in-kernel block type (ext4_fsblk_t) from sector_t to unsigned long long. Remove ext4 block type string micro E3FSBLK, replaced with "%llu" [akpm@osdl.org: build fix] Signed-off-by: Mingming Cao Signed-off-by: Dave Kleikamp Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] ext4: 64bit metadata

2006-10-11T18:14:17Z

In-kernel super block changes to support >32 bit free blocks numbers. Signed-off-by: Laurent Vivier Signed-off-by: Dave Kleikamp Signed-off-by: Alexandre Ratchov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds