kernel.git/fs/ext4/file.c, branch linux-2.6.37.y

ext4: improve llseek error handling for overly large seek offsets

2010-10-28T01:30:06Z

The llseek system call should return EINVAL if passed a seek offset which results in a write error. What this maximum offset should be depends on whether or not the huge_file file system feature is set, and whether or not the file is extent based or not. If the file has no "EXT4_EXTENTS_FL" flag, the maximum size which can be written (write systemcall) is different from the maximum size which can be sought (lseek systemcall). For example, the following 2 cases demonstrates the differences between the maximum size which can be written, versus the seek offset allowed by the llseek system call: #1: mkfs.ext3 ; mount -t ext4 #2: mkfs.ext3 ; tune2fs -Oextent,huge_file ; mount -t ext4 Table. the max file size which we can write or seek at each filesystem feature tuning and file flag setting +============+===============================+===============================+ | \ File flag| | | | \ | !EXT4_EXTENTS_FL | EXT4_EXTETNS_FL | |case \| | | +------------+-------------------------------+-------------------------------+ | #1 | write: 2194719883264 | write: -------------- | | | seek: 2199023251456 | seek: -------------- | +------------+-------------------------------+-------------------------------+ | #2 | write: 4402345721856 | write: 17592186044415 | | | seek: 17592186044415 | seek: 17592186044415 | +------------+-------------------------------+-------------------------------+ The differences exist because ext4 has 2 maxbytes which are sb->s_maxbytes (= extent-mapped maxbytes) and EXT4_SB(sb)->s_bitmap_maxbytes (= block-mapped maxbytes). Although generic_file_llseek uses only extent-mapped maxbytes. (llseek of ext4_file_operations is generic_file_llseek which uses sb->s_maxbytes.) Therefore we create ext4 llseek function which uses 2 maxbytes. The new own function originates from generic_file_llseek(). If the file flag, "EXT4_EXTENTS_FL" is not set, the function alters inode->i_sb->s_maxbytes into EXT4_SB(inode->i_sb)->s_bitmap_maxbytes. Signed-off-by: Toshiyuki Okajima Signed-off-by: "Theodore Ts'o" Cc: Andreas Dilger

ext4: fix EFBIG edge case when writing to large non-extent file

2010-07-27T15:56:07Z

By running the following reproducer, we can confirm that the write system call returns with 0 when it should return the error EFBIG. #!/bin/sh /bin/dd if=/dev/zero of=./img bs=1k count=1 seek=1024k > /dev/null 2>&1 /sbin/mkfs.ext3 -Fq ./img /bin/mount -o loop -t ext4 ./img /mnt /bin/touch /mnt/file strace /bin/dd if=/dev/zero of=/mnt/file conv=notrunc bs=1k count=1 seek=$((2194719883264/1024)) 2>&1 | /bin/egrep "write.* 1024\) = " /bin/umount /mnt exit Signed-off-by: Toshiyuki Okajima Signed-off-by: "Theodore Ts'o" Cc: Eric Sandeen

ext4: Clean up s_dirt handling

2010-06-12T03:14:04Z

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"

ext4: Use bitops to read/modify i_flags in struct ext4_inode_info

2010-05-17T02:00:00Z

At several places we modify EXT4_I(inode)->i_flags without holding i_mutex (ext4_do_update_inode, ...). These modifications are racy and we can lose updates to i_flags. So convert handling of i_flags to use bitops which are atomic. https://bugzilla.kernel.org/show_bug.cgi?id=15792 Signed-off-by: Dmitry Monakhov Signed-off-by: "Theodore Ts'o"

Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs-2.6

2010-03-05T21:20:53Z

* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs-2.6: (33 commits) quota: stop using QUOTA_OK / NO_QUOTA dquot: cleanup dquot initialize routine dquot: move dquot initialization responsibility into the filesystem dquot: cleanup dquot drop routine dquot: move dquot drop responsibility into the filesystem dquot: cleanup dquot transfer routine dquot: move dquot transfer responsibility into the filesystem dquot: cleanup inode allocation / freeing routines dquot: cleanup space allocation / freeing routines ext3: add writepage sanity checks ext3: Truncate allocated blocks if direct IO write fails to update i_size quota: Properly invalidate caches even for filesystems with blocksize < pagesize quota: generalize quota transfer interface quota: sb_quota state flags cleanup jbd: Delay discarding buffers in journal_unmap_buffer ext3: quota_write cross block boundary behaviour quota: drop permission checks from xfs_fs_set_xstate/xfs_fs_set_xquota quota: split out compat_sys_quotactl support from quota.c quota: split out netlink notification support from quota.c quota: remove invalid optimization from quota_sync_all ... Fixed trivial conflicts in fs/namei.c and fs/ufs/inode.c

Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

2010-03-05T18:47:00Z

* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (36 commits) ext4: fix up rb_root initializations to use RB_ROOT ext4: Code cleanup for EXT4_IOC_MOVE_EXT ioctl ext4: Fix the NULL reference in double_down_write_data_sem() ext4: Fix insertion point of extent in mext_insert_across_blocks() ext4: consolidate in_range() definitions ext4: cleanup to use ext4_grp_offs_to_block() ext4: cleanup to use ext4_group_first_block_no() ext4: Release page references acquired in ext4_da_block_invalidatepages ext4: Fix ext4_quota_write cross block boundary behaviour ext4: Convert BUG_ON checks to use ext4_error() instead ext4: Use direct_IO_no_locking in ext4 dio read ext4: use ext4_get_block_write in buffer write ext4: mechanical rename some of the direct I/O get_block's identifiers ext4: make "offset" consistent in ext4_check_dir_entry() ext4: Handle non empty on-disk orphan link ext4: explicitly remove inode from orphan list after failed direct io ext4: fix error handling in migrate ext4: deprecate obsoleted mount options ext4: Fix fencepost error in chosing choosing group vs file preallocation. jbd2: clean up an assertion in jbd2_journal_commit_transaction() ...

dquot: cleanup dquot initialize routine

2010-03-04T23:20:30Z

Get rid of the initialize dquot operation - it is now always called from the filesystem and if a filesystem really needs it's own (which none currently does) it can just call into it's own routine directly. Rename the now static low-level dquot_initialize helper to __dquot_initialize and vfs_dq_init to dquot_initialize to have a consistent namespace. Signed-off-by: Christoph Hellwig Signed-off-by: Jan Kara

dquot: move dquot initialization responsibility into the filesystem

2010-03-04T23:20:30Z

Currently various places in the VFS call vfs_dq_init directly. This means we tie the quota code into the VFS. Get rid of that and make the filesystem responsible for the initialization. For most metadata operations this is a straight forward move into the methods, but for truncate and open it's a bit more complicated. For truncate we currently only call vfs_dq_init for the sys_truncate case because open already takes care of it for ftruncate and open(O_TRUNC) - the new code causes an additional vfs_dq_init for those which is harmless. For open the initialization is moved from do_filp_open into the open method, which means it happens slightly earlier now, and only for regular files. The latter is fine because we don't need to initialize it for operations on special files, and we already do it as part of the namespace operations for directories. Add a dquot_file_open helper that filesystems that support generic quotas can use to fill in ->open. Signed-off-by: Christoph Hellwig Signed-off-by: Jan Kara

Get rid of mnt_mountpoint abuses in ext4

2010-03-03T19:07:54Z

path to mnt/mnt->mnt_root is no worse than that to mnt->mnt_parent/mnt->mnt_mountpoint *and* needs no pinning the sucker down (mnt is not going away and mnt->mnt_root won't change) Signed-off-by: Al Viro

ext4: Use bitops to read/modify EXT4_I(inode)->i_state

2010-01-24T19:34:07Z

At several places we modify EXT4_I(inode)->i_state without holding i_mutex (ext4_release_file, ext4_bmap, ext4_journalled_writepage, ext4_do_update_inode, ...). These modifications are racy and we can lose updates to i_state. So convert handling of i_state to use bitops which are atomic. Cc: Jan Kara Signed-off-by: "Theodore Ts'o"