mirror_zfs/include/os/linux/zfs/sys
Brian Behlendorf c7db374ac6 Fix buffered/direct/mmap I/O race
When a page is faulted in for memory mapped I/O the page lock
may be dropped before it has been read and marked up to date.
If a buffered read encounters such a page in mappedread() it
must wait until the page has been updated. Failure to do so
will result in a panic on debug builds and incorrect data on
production builds.

The critical part of this change is in mappedread() where pages
which are not up to date are now handled. Additionally, it
includes the following simplifications.

- zfs_getpage() and zfs_fillpage() could be passed an array of
  pages. This could be more efficient if it was used but in
  practice only a single page was ever provided. These
  interfaces were simplified to acknowledge that.

- update_pages() was modified to correctly set the PG_error bit
  on a page when it cannot be read by dmu_read().

- Setting PG_error and PG_uptodate was moved to zfs_fillpage()
  from zpl_readpage_common(). This is consistent with the
  handling in update_pages() and mappedread().

- Minor additional refactoring to comments and variable
  declarations to improve readability.

- Add a test case to exercise concurrent buffered, direct,
  and mmap IO to the same file.

- Reduce the mmap_sync test case default run time.

Reviewed-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #13608
Closes #14498
2023-04-21 13:12:35 -07:00
..
Makefile.am Share zfs_fsync, zfs_read, zfs_write, et al between Linux and FreeBSD 2020-10-21 14:08:06 -07:00
policy.h Share zfs_fsync, zfs_read, zfs_write, et al between Linux and FreeBSD 2020-10-21 14:08:06 -07:00
sha2.h Move sha2.h to platform code 2019-10-31 15:45:58 -07:00
trace_acl.h Remove zpl_revalidate: fix snapshot rollback 2022-12-01 12:39:42 -08:00
trace_arc.h Fix/improve dbuf hits accounting 2021-09-14 14:31:22 -07:00
trace_common.h OpenZFS restructuring - move linux tracing code to platform directories 2019-09-11 14:25:53 -07:00
trace_dbgmsg.h Enable use of DTRACE_PROBE* macros in "spl" module 2019-11-01 13:13:43 -07:00
trace_dbuf.h Factor out some dbuf subroutines and add state change tracing 2020-02-18 11:21:37 -08:00
trace_dmu.h OpenZFS restructuring - move linux tracing code to platform directories 2019-09-11 14:25:53 -07:00
trace_dnode.h OpenZFS restructuring - move linux tracing code to platform directories 2019-09-11 14:25:53 -07:00
trace_multilist.h OpenZFS restructuring - move linux tracing code to platform directories 2019-09-11 14:25:53 -07:00
trace_rrwlock.h OpenZFS restructuring - move linux tracing code to platform directories 2019-09-11 14:25:53 -07:00
trace_txg.h OpenZFS restructuring - move linux tracing code to platform directories 2019-09-11 14:25:53 -07:00
trace_vdev.h OpenZFS restructuring - move linux tracing code to platform directories 2019-09-11 14:25:53 -07:00
trace_zfs.h Enable use of DTRACE_PROBE* macros in "spl" module 2019-11-01 13:13:43 -07:00
trace_zil.h OpenZFS restructuring - move linux tracing code to platform directories 2019-09-11 14:25:53 -07:00
trace_zio.h OpenZFS restructuring - move linux tracing code to platform directories 2019-09-11 14:25:53 -07:00
trace_zrlock.h OpenZFS restructuring - move linux tracing code to platform directories 2019-09-11 14:25:53 -07:00
zfs_bootenv_os.h zfs label bootenv should store data as nvlist 2020-09-15 15:42:27 -07:00
zfs_context_os.h Use fallthrough macro 2021-11-02 09:50:30 -07:00
zfs_ctldir.h Throw const on some strings 2020-10-02 17:44:10 -07:00
zfs_dir.h Eliminate Linux specific inode usage from common code 2019-12-11 11:53:57 -08:00
zfs_vfsops_os.h Macroify teardown lock handling 2021-03-12 15:51:39 -08:00
zfs_vnops_os.h Fix buffered/direct/mmap I/O race 2023-04-21 13:12:35 -07:00
zfs_znode_impl.h Fix lseek(SEEK_DATA/SEEK_HOLE) mmap consistency 2021-11-05 08:08:55 -07:00
zpl.h linux 6.2 compat: zpl_set_acl arg2 is now struct dentry 2023-01-24 15:36:08 -08:00