diff options
| author |   Dan Williams <dan.j.williams@intel.com> | 2017-12-22 22:02:48 -0800 |
|---|---|---|
| committer | Dan Williams <dan.j.williams@intel.com> | 2018-04-03 05:41:19 -0700 |
| commit | d2c997c0f14535eff68d8ed9c2f1c5e100625751 (patch) | |
| tree | 5cb06d1486db2db5cb9ad022d070ba425368ae45 /drivers/dax | |
| parent | ext2, dax: introduce ext2_dax_aops (diff) | |
| download | linux-dev-d2c997c0f14535eff68d8ed9c2f1c5e100625751.tar.xz linux-dev-d2c997c0f14535eff68d8ed9c2f1c5e100625751.zip | |
fs, dax: use page->mapping to warn if truncate collides with a busy page
Catch cases where extent unmap operations encounter pages that are
pinned / busy. Typically this is pinned pages that are under active dma.
This warning is a canary for potential data corruption as truncated
blocks could be allocated to a new file while the device is still
performing i/o.
Here is an example of a collision that this implementation catches:
WARNING: CPU: 2 PID: 1286 at fs/dax.c:343 dax_disassociate_entry+0x55/0x80
[..]
Call Trace:
__dax_invalidate_mapping_entry+0x6c/0xf0
dax_delete_mapping_entry+0xf/0x20
truncate_exceptional_pvec_entries.part.12+0x1af/0x200
truncate_inode_pages_range+0x268/0x970
? tlb_gather_mmu+0x10/0x20
? up_write+0x1c/0x40
? unmap_mapping_range+0x73/0x140
xfs_free_file_space+0x1b6/0x5b0 [xfs]
? xfs_file_fallocate+0x7f/0x320 [xfs]
? down_write_nested+0x40/0x70
? xfs_ilock+0x21d/0x2f0 [xfs]
xfs_file_fallocate+0x162/0x320 [xfs]
? rcu_read_lock_sched_held+0x3f/0x70
? rcu_sync_lockdep_assert+0x2a/0x50
? __sb_start_write+0xd0/0x1b0
? vfs_fallocate+0x20c/0x270
vfs_fallocate+0x154/0x270
SyS_fallocate+0x43/0x80
entry_SYSCALL_64_fastpath+0x1f/0x96
Cc: Jeff Moyer <jmoyer@redhat.com>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Diffstat (limited to 'drivers/dax')
0 files changed, 0 insertions, 0 deletions