- 11 Oct, 2014 1 commit
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Eric Sandeen authored
Delalloc write journal reservations only reserve 1 credit, to update the inode if necessary. However, it may happen once in a filesystem's lifetime that a file will cross the 2G threshold, and require the LARGE_FILE feature to be set in the superblock as well, if it was not set already. This overruns the transaction reservation, and can be demonstrated simply on any ext4 filesystem without the LARGE_FILE feature already set: dd if=/dev/zero of=testfile bs=1 seek=2147483646 count=1 \ conv=notrunc of=testfile sync dd if=/dev/zero of=testfile bs=1 seek=2147483647 count=1 \ conv=notrunc of=testfile leads to: EXT4-fs: ext4_do_update_inode:4296: aborting transaction: error 28 in __ext4_handle_dirty_super EXT4-fs error (device loop0) in ext4_do_update_inode:4301: error 28 EXT4-fs error (device loop0) in ext4_reserve_inode_write:4757: Readonly filesystem EXT4-fs error (device loop0) in ext4_dirty_inode:4876: error 28 EXT4-fs error (device loop0) in ext4_da_write_end:2685: error 28 Adjust the number of credits based on whether the flag is already set, and whether the current write may extend past the LARGE_FILE limit. Signed-off-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Andreas Dilger <adilger@dilger.ca> Cc: stable@vger.kernel.org
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- 06 Oct, 2014 2 commits
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Theodore Ts'o authored
If there is a corrupted file system which has directory entries that point at reserved, metadata inodes, prohibit them from being used by treating them the same way we treat Boot Loader inodes --- that is, mark them to be bad inodes. This prohibits them from being opened, deleted, or modified via chmod, chown, utimes, etc. In particular, this prevents a corrupted file system which has a directory entry which points at the journal inode from being deleted and its blocks released, after which point Much Hilarity Ensues. Reported-by: Sami Liedes <sami.liedes@iki.fi> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@vger.kernel.org
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Theodore Ts'o authored
The boot loader inode (inode #5) should never be visible in the directory hierarchy, but it's possible if the file system is corrupted that there will be a directory entry that points at inode #5. In order to avoid accidentally trashing it, when such a directory inode is opened, the inode will be marked as a bad inode, so that it's not possible to modify (or read) the inode from userspace. Unfortunately, when we unlink this (invalid/illegal) directory entry, we will put the bad inode on the ophan list, and then when try to unlink the directory, we don't actually remove the bad inode from the orphan list before freeing in-memory inode structure. This means the in-memory orphan list is corrupted, leading to a kernel oops. In addition, avoid truncating a bad inode in ext4_destroy_inode(), since truncating the boot loader inode is not a smart thing to do. Reported-by: Sami Liedes <sami.liedes@iki.fi> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@vger.kernel.org
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- 03 Oct, 2014 1 commit
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Dmitry Monakhov authored
Otherwise this provokes complain like follows: WARNING: CPU: 12 PID: 5795 at fs/ext4/ext4_jbd2.c:48 ext4_journal_check_start+0x4e/0xa0() Modules linked in: brd iTCO_wdt lpc_ich mfd_core igb ptp dm_mirror dm_region_hash dm_log dm_mod CPU: 12 PID: 5795 Comm: python Not tainted 3.17.0-rc2-00175-gae5344f #158 Hardware name: Intel Corporation W2600CR/W2600CR, BIOS SE5C600.86B.99.99.x028.061320111235 06/13/2011 0000000000000030 ffff8808116cfd28 ffffffff815c7dfc 0000000000000030 0000000000000000 ffff8808116cfd68 ffffffff8106ce8c ffff8808116cfdc8 ffff880813b16000 ffff880806ad6ae8 ffffffff81202008 0000000000000000 Call Trace: [<ffffffff815c7dfc>] dump_stack+0x51/0x6d [<ffffffff8106ce8c>] warn_slowpath_common+0x8c/0xc0 [<ffffffff81202008>] ? ext4_ioctl+0x9e8/0xeb0 [<ffffffff8106ceda>] warn_slowpath_null+0x1a/0x20 [<ffffffff8122867e>] ext4_journal_check_start+0x4e/0xa0 [<ffffffff81228c10>] __ext4_journal_start_sb+0x90/0x110 [<ffffffff81202008>] ext4_ioctl+0x9e8/0xeb0 [<ffffffff8107b0bd>] ? ptrace_stop+0x24d/0x2f0 [<ffffffff81088530>] ? alloc_pid+0x480/0x480 [<ffffffff8107b1f2>] ? ptrace_do_notify+0x92/0xb0 [<ffffffff81186545>] do_vfs_ioctl+0x4e5/0x550 [<ffffffff815cdbcb>] ? _raw_spin_unlock_irq+0x2b/0x40 [<ffffffff81186603>] SyS_ioctl+0x53/0x80 [<ffffffff815ce2ce>] tracesys+0xd0/0xd5 Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@vger.kernel.org
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- 02 Oct, 2014 6 commits
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Dmitry Monakhov authored
It is reasonable to prepend newly created index to older one. [ Dropped no longer used function parameter newext. -tytso ] Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
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Dmitry Monakhov authored
Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
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Dmitry Monakhov authored
Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
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Li Xi authored
When ext4_do_update_inode() gets error from ext4_inode_blocks_set(), error number should be returned. Signed-off-by: Li Xi <lixi@ddn.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Eric Sandeen <sandeen@redhat.com> Reviewed-by: Jan Kara <jack@suse.cz>
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Jan Kara authored
Use truncate_isize_extended() when hole is being created in a file so that ->page_mkwrite() will get called for the partial tail page if it is mmaped (see the first patch in the series for details). Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@vger.kernel.org
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Jan Kara authored
->page_mkwrite() is used by filesystems to allocate blocks under a page which is becoming writeably mmapped in some process' address space. This allows a filesystem to return a page fault if there is not enough space available, user exceeds quota or similar problem happens, rather than silently discarding data later when writepage is called. However VFS fails to call ->page_mkwrite() in all the cases where filesystems need it when blocksize < pagesize. For example when blocksize = 1024, pagesize = 4096 the following is problematic: ftruncate(fd, 0); pwrite(fd, buf, 1024, 0); map = mmap(NULL, 1024, PROT_WRITE, MAP_SHARED, fd, 0); map[0] = 'a'; ----> page_mkwrite() for index 0 is called ftruncate(fd, 10000); /* or even pwrite(fd, buf, 1, 10000) */ mremap(map, 1024, 10000, 0); map[4095] = 'a'; ----> no page_mkwrite() called At the moment ->page_mkwrite() is called, filesystem can allocate only one block for the page because i_size == 1024. Otherwise it would create blocks beyond i_size which is generally undesirable. But later at ->writepage() time, we also need to store data at offset 4095 but we don't have block allocated for it. This patch introduces a helper function filesystems can use to have ->page_mkwrite() called at all the necessary moments. Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@vger.kernel.org
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- 18 Sep, 2014 6 commits
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Theodore Ts'o authored
There's no longer any need to have a separate set of super_operations for nojournal mode. Signed-off-by: Theodore Ts'o <tytso@mit.edu>
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Theodore Ts'o authored
Through an oversight, when we added nojournal support to ext4, we didn't add support to allow file system freezing. This is relatively easy to add, so let's do it. Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reported-by: Dexuan Cui <decui@microsoft.com>
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Theodore Ts'o authored
This allows us to eliminate duplicate code, and eventually allow us to also fold ext4_sops and ext4_nojournal_sops together. Signed-off-by: Theodore Ts'o <tytso@mit.edu>
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Jan Kara authored
The check whether quota format is set even though there are no quota files with journalled quota is pointless and it actually makes it impossible to turn off journalled quotas (as there's no way to unset journalled quota format). Just remove the check. CC: stable@vger.kernel.org Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
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Jan Kara authored
__jbd2_journal_clean_checkpoint_list() returns number of buffers it freed but noone was using the value so just stop doing that. This also allows for simplifying the calling convention for journal_clean_once_cp_list(). Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
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Jan Kara authored
Yuanhan has reported that when he is running fsync(2) heavy workload creating new files over ramdisk, significant amount of time is spent in __jbd2_journal_clean_checkpoint_list() trying to clean old transactions (but they cannot be cleaned up because flusher hasn't yet checkpointed those buffers). The workload can be generated by: fs_mark -d /fs/ram0/1 -D 2 -N 2560 -n 1000000 -L 1 -S 1 -s 4096 Reduce the amount of scanning by stopping to scan the transaction list once we find a transaction that cannot be checkpointed. Note that this way of cleaning is still enough to keep freeing space in the journal after fully checkpointed transactions. Reported-and-tested-by: Yuanhan Liu <yuanhan.liu@linux.intel.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
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- 16 Sep, 2014 4 commits
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Dmitry Monakhov authored
Production fs likely compiled/mounted w/o jbd debugging, so orphan list clearing will be silent. Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
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Dmitry Monakhov authored
If EIO happens after we have dropped j_state_lock, we won't notice that the journal has been aborted. So it is reasonable to move this check after we have grabbed the j_checkpoint_mutex and re-grabbed the j_state_lock. This patch helps to prevent false positive complain after EIO. #DMESG: __jbd2_log_wait_for_space: needed 8448 blocks and only had 8386 space available __jbd2_log_wait_for_space: no way to get more journal space in ram1-8 ------------[ cut here ]------------ WARNING: CPU: 15 PID: 6739 at fs/jbd2/checkpoint.c:168 __jbd2_log_wait_for_space+0x188/0x200() Modules linked in: brd iTCO_wdt lpc_ich mfd_core igb ptp dm_mirror dm_region_hash dm_log dm_mod CPU: 15 PID: 6739 Comm: fsstress Tainted: G W 3.17.0-rc2-00429-g684de57 #139 Hardware name: Intel Corporation W2600CR/W2600CR, BIOS SE5C600.86B.99.99.x028.061320111235 06/13/2011 00000000000000a8 ffff88077aaab878 ffffffff815c1a8c 00000000000000a8 0000000000000000 ffff88077aaab8b8 ffffffff8106ce8c ffff88077aaab898 ffff8807c57e6000 ffff8807c57e6028 0000000000002100 ffff8807c57e62f0 Call Trace: [<ffffffff815c1a8c>] dump_stack+0x51/0x6d [<ffffffff8106ce8c>] warn_slowpath_common+0x8c/0xc0 [<ffffffff8106ceda>] warn_slowpath_null+0x1a/0x20 [<ffffffff812419f8>] __jbd2_log_wait_for_space+0x188/0x200 [<ffffffff8123be9a>] start_this_handle+0x4da/0x7b0 [<ffffffff810990e5>] ? local_clock+0x25/0x30 [<ffffffff810aba87>] ? lockdep_init_map+0xe7/0x180 [<ffffffff8123c5bc>] jbd2__journal_start+0xdc/0x1d0 [<ffffffff811f2414>] ? __ext4_new_inode+0x7f4/0x1330 [<ffffffff81222a38>] __ext4_journal_start_sb+0xf8/0x110 [<ffffffff811f2414>] __ext4_new_inode+0x7f4/0x1330 [<ffffffff810ac359>] ? lock_release_holdtime+0x29/0x190 [<ffffffff812025bb>] ext4_create+0x8b/0x150 [<ffffffff8117fe3b>] vfs_create+0x7b/0xb0 [<ffffffff8118097b>] do_last+0x7db/0xcf0 [<ffffffff8117e31d>] ? inode_permission+0x4d/0x50 [<ffffffff811845d2>] path_openat+0x242/0x590 [<ffffffff81191a76>] ? __alloc_fd+0x36/0x140 [<ffffffff81184a6a>] do_filp_open+0x4a/0xb0 [<ffffffff81191b61>] ? __alloc_fd+0x121/0x140 [<ffffffff81172f20>] do_sys_open+0x170/0x220 [<ffffffff8117300e>] SyS_open+0x1e/0x20 [<ffffffff811715d6>] SyS_creat+0x16/0x20 [<ffffffff815c7e12>] system_call_fastpath+0x16/0x1b ---[ end trace cd71c831f82059db ]--- Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
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Darrick J. Wong authored
Free the buffer head if the journal descriptor block fails checksum verification. This is the jbd2 port of the e2fsprogs patch "e2fsck: free bh on csum verify error in do_one_pass". Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Eric Sandeen <sandeen@redhat.com> Cc: stable@vger.kernel.org
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Darrick J. Wong authored
When loading extended attributes, check each entry's value offset to make sure it doesn't collide with the entries. Without this check it is easy to crash the kernel by mounting a malicious FS containing a file with an EA wherein e_value_offs = 0 and e_value_size > 0 and then deleting the EA, which corrupts the name list. (See the f_ea_value_crash test's FS image in e2fsprogs for an example.) Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@vger.kernel.org
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- 11 Sep, 2014 6 commits
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Darrick J. Wong authored
If inline->extent conversion fails (most probably due to ENOSPC) and we release the temporary page that we allocated to transfer the file contents, don't keep using the page pointer after releasing the page. This occasionally leads to complaints about evicting locked pages or hangs when blocksize > pagesize, because it's possible for the page to get reallocated elsewhere in the meantime. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Jan Kara <jack@suse.cz> Cc: Tao Ma <tm@tao.ma>
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Darrick J. Wong authored
If the external journal device has metadata_csum enabled, verify that the superblock checksum matches the block before we try to mount. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
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Darrick J. Wong authored
Clear all three journal checksum feature flags before turning on whichever journal checksum options we want. Rearrange the error checking so that newer flags get complained about first. Reported-by: TR Reardon <thomas_reardon@hotmail.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
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Lukas Czerner authored
Currently sysfs feature files uses ext4_attr_ops as the file operations to show/store data. However the feature files is not supposed to contain any data at all, the sole existence of the file means that the module support the feature. Moreover, none of the sysfs feature attributes actually register show/store functions so that would not be a problem. However if a sysfs feature attribute register a show or store function we might be in trouble because the kobject in this case is _not_ embedded in the ext4_sb_info structure as ext4_attr_show/store expect. So just to be safe, provide separate empty sysfs_ops to use in ext4_feat_ktype. This might safe us from potential problems in the future. As a bonus we can "store" something more descriptive than nothing in the files, so let it contain "enabled" to make it clear that the feature is really present in the module. Signed-off-by: Lukas Czerner <lczerner@redhat.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
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Lukas Czerner authored
Currently there is no easy way to tell that the mounted file system contains errors other than checking for log messages, or reading the information directly from superblock. This patch adds new sysfs entries: errors_count (number of fs errors we encounter) first_error_time (unix timestamp for the first error we see) last_error_time (unix timestamp for the last error we see) If the file system is not marked as containing errors then any of the file will return 0. Otherwise it will contain valid information. More details about the errors should as always be found in the logs. Signed-off-by: Lukas Czerner <lczerner@redhat.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
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Jan Kara authored
MAXQUOTAS value defines maximum number of quota types VFS supports. This isn't necessarily the number of types ext4 supports. Although ext4 will support project quotas, use ext4 private definition for consistency with other filesystems. Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
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- 05 Sep, 2014 3 commits
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Gioh Kim authored
Sicne the jbd/jbd2 superblock is not released until the file system is unmounted, allocate the buffer cache from the non-moveable area to allow page migration and CMA allocations to more easily succeed. Signed-off-by: Gioh Kim <gioh.kim@lge.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Jan Kara <jack@suse.cz>
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Gioh Kim authored
Since the ext4 superblock is not released until the file system is unmounted, allocate the buffer cache entry for the ext4 superblock out of the non-moveable are to allow page migrations and thus CMA allocations to more easily succeed if the CMA area is limited. Signed-off-by: Gioh Kim <gioh.kim@lge.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Jan Kara <jack@suse.cz>
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Gioh Kim authored
A buffer cache is allocated from movable area because it is referred for a while and released soon. But some filesystems are taking buffer cache for a long time and it can disturb page migration. New APIs are introduced to allocate buffer cache with user specific flag. *_gfp APIs are for user want to set page allocation flag for page cache allocation. And *_unmovable APIs are for the user wants to allocate page cache from non-movable area. Signed-off-by: Gioh Kim <gioh.kim@lge.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Jan Kara <jack@suse.cz>
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- 04 Sep, 2014 6 commits
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Theodore Ts'o authored
Suggested-by: Andreas Dilger <adilger@dilger.ca> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
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Jan Kara authored
When we discover written out buffer in transaction checkpoint list we don't have to recheck validity of a transaction. Either this is the last buffer in a transaction - and then we are done - or this isn't and then we can just take another buffer from the checkpoint list without dropping j_list_lock. Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
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Theodore Ts'o authored
The __jbd2_journal_remove_checkpoint() doesn't require an elevated b_count; indeed, until the jh structure gets released by the call to jbd2_journal_put_journal_head(), the bh's b_count is elevated by virtue of the existence of the jh structure. Suggested-by: Jan Kara <jack@suse.cz> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
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Theodore Ts'o authored
Having done a full regression test, we can now drop the DELALLOC_RESERVED state flag. Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Jan Kara <jack@suse.cz>
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Theodore Ts'o authored
The EXT4_STATE_DELALLOC_RESERVED flag was originally implemented because it was too hard to make sure the mballoc and get_block flags could be reliably passed down through all of the codepaths that end up calling ext4_mb_new_blocks(). Since then, we have mb_flags passed down through most of the code paths, so getting rid of EXT4_STATE_DELALLOC_RESERVED isn't as tricky as it used to. This commit plumbs in the last of what is required, and then adds a WARN_ON check to make sure we haven't missed anything. If this passes a full regression test run, we can then drop EXT4_STATE_DELALLOC_RESERVED. Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Jan Kara <jack@suse.cz>
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Theodore Ts'o authored
Instead of initializing the allocation_request structure in ext4_alloc_branch(), set it up in ext4_ind_map_blocks(), and then pass it to ext4_alloc_branch() and ext4_splice_branch(). This allows ext4_ind_map_blocks to pass flags in the allocation request structure without having to add Yet Another argument to ext4_alloc_branch(). Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Jan Kara <jack@suse.cz>
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- 02 Sep, 2014 5 commits
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Zheng Liu authored
This commit adds some statictics in extent status tree shrinker. The purpose to add these is that we want to collect more details when we encounter a stall caused by extent status tree shrinker. Here we count the following statictics: stats: the number of all objects on all extent status trees the number of reclaimable objects on lru list cache hits/misses the last sorted interval the number of inodes on lru list average: scan time for shrinking some objects the number of shrunk objects maximum: the inode that has max nr. of objects on lru list the maximum scan time for shrinking some objects The output looks like below: $ cat /proc/fs/ext4/sda1/es_shrinker_info stats: 28228 objects 6341 reclaimable objects 5281/631 cache hits/misses 586 ms last sorted interval 250 inodes on lru list average: 153 us scan time 128 shrunk objects maximum: 255 inode (255 objects, 198 reclaimable) 125723 us max scan time If the lru list has never been sorted, the following line will not be printed: 586ms last sorted interval If there is an empty lru list, the following lines also will not be printed: 250 inodes on lru list ... maximum: 255 inode (255 objects, 198 reclaimable) 0 us max scan time Meanwhile in this commit a new trace point is defined to print some details in __ext4_es_shrink(). Cc: Andreas Dilger <adilger.kernel@dilger.ca> Cc: Jan Kara <jack@suse.cz> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Zheng Liu <wenqing.lz@taobao.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
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Zheng Liu authored
This commit improves the trace point of extents status tree. We rename trace_ext4_es_shrink_enter in ext4_es_count() because it is also used in ext4_es_scan() and we can not identify them from the result. Further this commit fixes a variable name in trace point in order to keep consistency with others. Cc: Andreas Dilger <adilger.kernel@dilger.ca> Cc: Jan Kara <jack@suse.cz> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Zheng Liu <wenqing.lz@taobao.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
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Seunghun Lee authored
get_blocks is renamed to get_block. Signed-off-by: Seunghun Lee <waydi1@gmail.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
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Darrick J. Wong authored
Enable by default the block_validity feature, which checks for collisions between newly allocated blocks and critical system metadata. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
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Theodore Ts'o authored
__wait_cp_io() is only called by jbd2_log_do_checkpoint(). Fold it in to make it a bit easier to understand. Signed-off-by: Theodore Ts'o <tytso@mit.edu>
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