This patch mostly controls the way inode are allocated in order to
make ialloc aware of flex_bg block group grouping. It achieves this
by bypassing the Orlov allocator when block group meta-data are packed
toghether through mke2fs. Since the impact on the block allocator is
minimal, this patch should have little or no effect on other block
allocation algorithms. By controlling the inode allocation, it can
basically control where the initial search for new block begins and
thus indirectly manipulate the block allocator.
This allocator favors data and meta-data locality so the disk will
gradually be filled from block group zero upward. This helps improve
performance by reducing seek time. Since the group of inode tables
within one flex_bg are treated as one giant inode table, uninitialized
block groups would not need to partially initialize as many inode
table as with Orlov which would help fsck time as the filesystem usage
goes up.
Signed-off-by: Jose R. Santos <jrs@us.ibm.com>
Signed-off-by: Valerie Clement <valerie.clement@bull.net>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Since this a non-static function, make it be ext4 specific to avoid
conflicts with potentially other filesystems.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
If the orphan node list includes valid, untruncatable nodes with nlink > 0
the ext4_orphan_cleanup loop which attempts to delete them will not do so,
causing it to loop forever. Fix by checking for such nodes in the
ext4_orphan_get function.
This patch fixes the second case (image hdb.20000009.softlockup.gz)
reported in http://bugzilla.kernel.org/show_bug.cgi?id=10882.
Signed-off-by: Duane Griffin <duaneg@dghda.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
We should mark the inode dirty only after initializing the extent
tree. Also if we fail during extent initialization we need
to call DQUOT_FREE_INODE.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Move ext4 headers out of include/linux. This is just the trivial move,
there's some more thing that could be done later.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
__FUNCTION__ is gcc-specific, use __func__
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This patch enables extent-formatted normal symlinks. Using extents
format allows a symlink to refer to a block number larger than 2^32
on large filesystems. We still don't enable extent format for fast
symlinks, which are contained in the inode itself.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
In addition, don't inherit EXT4_EXTENTS_FL from parent directory.
If we have a directory with extent flag set and later mount the file
system with -o noextents, the files created in that directory will also
have extent flag set but we would not have called ext4_ext_tree_init for
them. This will cause error later when we are verifying the extent header
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Acked-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Stop the EXT4 filesystem from using iget() and read_inode(). Replace
ext4_read_inode() with ext4_iget(), and call that instead of iget().
ext4_iget() then uses iget_locked() directly and returns a proper error code
instead of an inode in the event of an error.
ext4_fill_super() returns any error incurred when getting the root inode
instead of EINVAL.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: "Theodore Ts'o" <tytso@mit.edu>
Acked-by: Jan Kara <jack@suse.cz>
Cc: <linux-ext4@vger.kernel.org>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Builds with EXT4FS_DEBUG defined (to enable ext4_debug()) fail
without these changes. Clean up some format warnings too.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Rename ext4_inode.i_dir_acl to i_size_high
drop ext4_inode_info.i_dir_acl as it is not used
Rename ext4_inode.i_size to ext4_inode.i_size_lo
Add helper function for accessing the ext4_inode combined i_size.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
This patch fixes various places where the group number is set to a negative
value.
Signed-off-by: Avantika Mathur <mathur@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
In many places variables for block group are of type int, which limits the
maximum number of block groups to 2^31. Each block group can have up to
2^15 blocks, with a 4K block size, and the max filesystem size is limited to
2^31 * (2^15 * 2^12) = 2^58 -- or 256 PB
This patch introduces a new type ext4_group_t, of type unsigned long, to
represent block group numbers in ext4.
All occurrences of block group variables are converted to type ext4_group_t.
Signed-off-by: Avantika Mathur <mathur@us.ibm.com>
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 <mathur@us.ibm.com>
Signed-off-by: Andreas Dilger <adilger@clusterfs.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Fragment support in ext2/3/4 was never implemented, and it probably will
never be implemented. So remove it from ext4.
Signed-off-by: Coly Li <coyli@suse.de>
Acked-by: Andreas Dilger <adilger@clusterfs.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
ext[234]_get_group_desc never tests the bh argument, and only sets it if it
is passed in; it is perfectly happy with a NULL bh argument. But, many
callers send one in and never use it. May as well call with NULL like
other callers who don't use the bh.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch adds nanosecond timestamps for ext4. This involves adding
*time_extra fields to the ext4_inode to extend the timestamps to
64-bits. Creation time is also added by this patch.
These extended fields will fit into an inode if the filesystem was
formatted with large inodes (-I 256 or larger) and there are currently
no EAs consuming all of the available space. For new inodes we always
reserve enough space for the kernel's known extended fields, but for
inodes created with an old kernel this might not have been the case. So
this patch also adds the EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE feature
flag(ro-compat so that older kernels can't create inodes with a smaller
extra_isize). which indicates if the fields fitting inside
s_min_extra_isize are available or not. If the expansion of inodes if
unsuccessful then this feature will be disabled. This feature is only
enabled if requested by the sysadmin.
None of the extended inode fields is critical for correct filesystem
operation.
Signed-off-by: Andreas Dilger <adilger@clusterfs.com>
Signed-off-by: Kalpak Shah <kalpak@clusterfs.com>
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
With CONFIG_LBD=n, sector_div() expands to a plain old divide. But ext4 is
_not_ passing in a sector_t as the first argument, so...
fs/built-in.o: In function `ext4_get_group_no_and_offset':
fs/ext4/balloc.c:39: undefined reference to `__umoddi3'
fs/ext4/balloc.c:41: undefined reference to `__udivdi3'
fs/built-in.o: In function `find_group_orlov':
fs/ext4/ialloc.c:278: undefined reference to `__udivdi3'
fs/built-in.o: In function `ext4_fill_super':
fs/ext4/super.c:1488: undefined reference to `__udivdi3'
fs/ext4/super.c:1488: undefined reference to `__umoddi3'
fs/ext4/super.c:1594: undefined reference to `__udivdi3'
fs/ext4/super.c:1601: undefined reference to `__umoddi3'
Fix that up by calling do_div() directly.
Also cast the arg to u64. do_div() is only defined on u64, and ext4_fsblk_t
is supposed to be opaque.
Note especially the changes to find_group_orlov(). It was attempting to do
do_div(int, unsigned long long);
which is royally screwed up. Switched it to plain old divide.
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
move '_hi' bits of block numbers in the larger part of the
block group descriptor structure
Signed-off-by: Alexandre Ratchov <alexandre.ratchov@bull.net>
Signed-off-by: Dave Kleikamp <shaggy@austin.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Redefine ext3 in-kernel filesystem block type (ext3_fsblk_t) from unsigned
long to sector_t, to allow kernel to handle >32 bit ext3 blocks.
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: Dave Kleikamp <shaggy@austin.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
On disk extents format:
/*
* this is extent on-disk structure
* it's used at the bottom of the tree
*/
struct ext3_extent {
__le32 ee_block; /* first logical block extent covers */
__le16 ee_len; /* number of blocks covered by extent */
__le16 ee_start_hi; /* high 16 bits of physical block */
__le32 ee_start; /* low 32 bigs of physical block */
};
Signed-off-by: Alex Tomas <alex@clusterfs.com>
Signed-off-by: Dave Kleikamp <shaggy@austin.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Reworked from a patch by Mingming Cao and Randy Dunlap
Signed-off-By: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: Dave Kleikamp <shaggy@austin.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Mingming Cao originally did this work, and Shaggy reproduced it using some
scripts from her.
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: Dave Kleikamp <shaggy@austin.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Start of the ext4 patch series. See Documentation/filesystems/ext4.txt for
details.
This is a simple copy of the files in fs/ext3 to fs/ext4 and
/usr/incude/linux/ext3* to /usr/include/ex4*
Signed-off-by: Dave Kleikamp <shaggy@austin.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
