Jeff Layton
5660e13d2f
fs: new infrastructure for writeback error handling and reporting ...
Most filesystems currently use mapping_set_error and
filemap_check_errors for setting and reporting/clearing writeback errors
at the mapping level. filemap_check_errors is indirectly called from
most of the filemap_fdatawait_* functions and from
filemap_write_and_wait*. These functions are called from all sorts of
contexts to wait on writeback to finish -- e.g. mostly in fsync, but
also in truncate calls, getattr, etc.
The non-fsync callers are problematic. We should be reporting writeback
errors during fsync, but many places spread over the tree clear out
errors before they can be properly reported, or report errors at
nonsensical times.
If I get -EIO on a stat() call, there is no reason for me to assume that
it is because some previous writeback failed. The fact that it also
clears out the error such that a subsequent fsync returns 0 is a bug,
and a nasty one since that's potentially silent data corruption.
This patch adds a small bit of new infrastructure for setting and
reporting errors during address_space writeback. While the above was my
original impetus for adding this, I think it's also the case that
current fsync semantics are just problematic for userland. Most
applications that call fsync do so to ensure that the data they wrote
has hit the backing store.
In the case where there are multiple writers to the file at the same
time, this is really hard to determine. The first one to call fsync will
see any stored error, and the rest get back 0. The processes with open
fds may not be associated with one another in any way. They could even
be in different containers, so ensuring coordination between all fsync
callers is not really an option.
One way to remedy this would be to track what file descriptor was used
to dirty the file, but that's rather cumbersome and would likely be
slow. However, there is a simpler way to improve the semantics here
without incurring too much overhead.
This set adds an errseq_t to struct address_space, and a corresponding
one is added to struct file. Writeback errors are recorded in the
mapping's errseq_t, and the one in struct file is used as the "since"
value.
This changes the semantics of the Linux fsync implementation such that
applications can now use it to determine whether there were any
writeback errors since fsync(fd) was last called (or since the file was
opened in the case of fsync having never been called).
Note that those writeback errors may have occurred when writing data
that was dirtied via an entirely different fd, but that's the case now
with the current mapping_set_error/filemap_check_error infrastructure.
This will at least prevent you from getting a false report of success.
The new behavior is still consistent with the POSIX spec, and is more
reliable for application developers. This patch just adds some basic
infrastructure for doing this, and ensures that the f_wb_err "cursor"
is properly set when a file is opened. Later patches will change the
existing code to use this new infrastructure for reporting errors at
fsync time.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
2017-07-06 07:02:25 -04:00
9p: Convert to separately allocated bdi
2017-04-20 12:09:55 -06:00
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
2016-10-10 20:16:43 -07:00
fs/affs: add rename exchange
2017-05-05 15:24:52 -04:00
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
2017-05-02 16:40:27 -07:00
Fix dead URLs to ftp.kernel.org
2017-03-28 16:16:52 +02:00
befs: make export work with cold dcache
2017-05-05 11:35:35 +01:00
Tigran has moved
2017-05-12 15:57:15 -07:00
Merge branch 'for-linus-4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
2017-05-10 08:33:17 -07:00
sched/headers: Prepare to remove <linux/cred.h> inclusion from <linux/sched.h>
2017-03-02 08:42:31 +01:00
ceph: check that the new inode size is within limits in ceph_fallocate()
2017-05-24 18:10:54 +02:00
[CIFS] Minor cleanup of xattr query function
2017-05-12 20:59:10 -05:00
coda: Convert to separately allocated bdi
2017-04-20 12:09:55 -06:00
Replace <asm/uaccess.h> with <linux/uaccess.h> globally
2016-12-24 11:46:01 -08:00
fscrypt: introduce helper function for filename matching
2017-05-04 11:44:37 -04:00
fs: constify tree_descr arrays passed to simple_fill_super()
2017-04-26 23:54:06 -04:00
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
2016-10-10 20:16:43 -07:00
net: Work around lockdep limitation in sockets that use sockets
2017-03-09 18:23:27 -08:00
ecryptfs: Convert to separately allocated bdi
2017-04-20 12:09:55 -06:00
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
2016-10-10 20:16:43 -07:00
Replace <asm/uaccess.h> with <linux/uaccess.h> globally
2016-12-24 11:46:01 -08:00
fs: semove set but not checked AOP_FLAG_UNINTERRUPTIBLE flag
2017-05-08 17:15:14 -07:00
Merge branch 'rebased-statx' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
2017-03-03 11:38:56 -08:00
fs: check for writeback errors after syncing out buffers in generic_file_fsync
2017-07-06 07:02:21 -04:00
dax, xfs, ext4: compile out iomap-dax paths in the FS_DAX=n case
2017-05-13 17:52:16 -07:00
Merge branch 'akpm' (patches from Andrew)
2017-05-08 18:17:56 -07:00
fat: fix using uninitialized fields of fat_inode/fsinfo_inode
2017-03-09 17:01:10 -08:00
KEYS: Differentiate uses of rcu_dereference_key() and user_key_payload()
2017-03-02 10:09:00 +11:00
Merge branch 'for-linus' of git://git.kernel.dk/linux-block
2017-05-20 16:12:30 -07:00
buffer: set errors in mapping at the time that the error occurs
2017-07-06 07:02:21 -04:00
fs: semove set but not checked AOP_FLAG_UNINTERRUPTIBLE flag
2017-05-08 17:15:14 -07:00
fs: semove set but not checked AOP_FLAG_UNINTERRUPTIBLE flag
2017-05-08 17:15:14 -07:00
vfs: remove ".readlink = generic_readlink" assignments
2016-12-09 16:45:04 +01:00
sched/headers: Prepare to move signal wakeup & sigpending methods from <linux/sched.h> into <linux/sched/signal.h>
2017-03-02 08:42:32 +01:00
hugetlbfs: fix offset overflow in hugetlbfs mmap
2017-04-13 18:24:21 -07:00
sched/headers: Prepare to remove <linux/cred.h> inclusion from <linux/sched.h>
2017-03-02 08:42:31 +01:00
jbd2: don't clear and reset errors after waiting on writeback
2017-07-06 07:02:22 -04:00
jffs2: fix spelling mistake: "requestied" -> "requested"
2017-04-19 11:35:55 -07:00
jfs: Remove jfs_get_inode_flags()
2017-04-19 14:21:23 +02:00
kernfs: Check KERNFS_HAS_RELEASE before calling kernfs_release_file()
2017-03-17 10:25:59 +09:00
Another RDMA update from Chuck Lever, and a bunch of miscellaneous
2017-05-10 13:29:23 -07:00
statx: Add a system call to make enhanced file info available
2017-03-02 20:51:15 -05:00
ncpfs: Convert to separately allocated bdi
2017-04-20 12:09:55 -06:00
Another RDMA update from Chuck Lever, and a bunch of miscellaneous
2017-05-10 13:29:23 -07:00
netns: make struct pernet_operations::id unsigned int
2016-11-18 10:59:15 -05:00
Another RDMA update from Chuck Lever, and a bunch of miscellaneous
2017-05-10 13:29:23 -07:00
fs: Remove SB_I_DYNBDI flag
2017-04-20 12:09:55 -06:00
fanotify: don't expose EOPENSTALE to userspace
2017-04-25 15:48:06 +02:00
sched/headers: Prepare to move signal wakeup & sigpending methods from <linux/sched.h> into <linux/sched/signal.h>
2017-03-02 08:42:32 +01:00
fs/ocfs2/cluster: use offset_in_page() macro
2017-05-03 15:52:07 -07:00
sched/headers: Prepare to remove <linux/cred.h> inclusion from <linux/sched.h>
2017-03-02 08:42:31 +01:00
Replace <asm/uaccess.h> with <linux/uaccess.h> globally
2016-12-24 11:46:01 -08:00
Some cleanups:
2017-05-05 13:36:10 -07:00
Merge branch 'overlayfs-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs
2017-05-10 09:03:48 -07:00
proc: try to remove use of FOLL_FORCE entirely
2017-05-09 08:45:16 -07:00
Annotation of module parameters that specify device settings
2017-05-10 19:13:03 -07:00
quota: Remove dquot_quotactl_ops
2017-04-19 14:21:23 +02:00
Replace <asm/uaccess.h> with <linux/uaccess.h> globally
2016-12-24 11:46:01 -08:00
reiserfs: use designated initializers
2017-05-08 17:15:11 -07:00
romfs: use different way to generate fsid for BLOCK or MTD
2017-01-24 16:26:14 -08:00
fs/pstore: fs/squashfs: change usage of LZ4 to work with new LZ4 version
2017-02-24 17:46:57 -08:00
sysfs: be careful of error returns from ops->show()
2017-04-08 17:33:32 +02:00
statx: Add a system call to make enhanced file info available
2017-03-02 20:51:15 -05:00
fs: constify tree_descr arrays passed to simple_fill_super()
2017-04-26 23:54:06 -04:00
This pull request contains updates for both UBI and UBIFS:
2017-05-13 10:23:12 -07:00
udf: use kmap_atomic for memcpy copying
2017-04-24 16:28:02 +02:00
fs: ufs: use ktime_get_real_ts64() for birthtime
2017-05-08 17:15:15 -07:00
Changed since last update:
2017-05-26 12:13:08 -07:00
Merge branch 'WIP.sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2017-03-03 10:16:38 -08:00
Replace <asm/uaccess.h> with <linux/uaccess.h> globally
2016-12-24 11:46:01 -08:00
sched/headers: Prepare for new header dependencies before moving code to <linux/sched/signal.h>
2017-03-02 08:42:29 +01:00
statx: Add a system call to make enhanced file info available
2017-03-02 20:51:15 -05:00
sched/headers: Prepare for new header dependencies before moving code to <linux/sched/task_stack.h>
2017-03-02 08:42:36 +01:00
sched/headers: Prepare to move cputime functionality from <linux/sched.h> into <linux/sched/cputime.h>
2017-03-02 08:42:39 +01:00
sched/headers: Prepare to move cputime functionality from <linux/sched.h> into <linux/sched/cputime.h>
2017-03-02 08:42:39 +01:00
sched/headers: Prepare for new header dependencies before moving code to <linux/sched/task_stack.h>
2017-03-02 08:42:36 +01:00
fs: constify tree_descr arrays passed to simple_fill_super()
2017-04-26 23:54:06 -04:00
fs: new infrastructure for writeback error handling and reporting
2017-07-06 07:02:25 -04:00
buffer: set errors in mapping at the time that the error occurs
2017-07-06 07:02:21 -04:00
chardev: add helper function to register char devs with a struct device
2017-03-21 06:44:32 +01:00
fs/compat.c: trim unused includes
2017-04-17 12:52:27 -04:00
fs/binfmt: Convert obsolete cputime type to nsecs
2017-02-01 09:13:51 +01:00
fs: compat: Remove warning from COMPATIBLE_IOCTL
2017-04-29 17:47:19 -04:00
sched/headers: Prepare for new header dependencies before moving code to <linux/sched/task_stack.h>
2017-03-02 08:42:36 +01:00
Merge branch 'akpm' (patches from Andrew)
2017-05-13 09:49:35 -07:00
fs: don't set *REFERENCED on single use objects
2017-05-03 11:47:05 -04:00
Replace <asm/uaccess.h> with <linux/uaccess.h> globally
2016-12-24 11:46:01 -08:00
fs: add i_blocksize()
2017-02-27 18:43:46 -08:00
sched/headers: Prepare to move signal wakeup & sigpending methods from <linux/sched.h> into <linux/sched/signal.h>
2017-03-02 08:42:32 +01:00
epoll: Add busy poll support to epoll with socket fds.
2017-03-24 20:49:31 -07:00
x86/arch_prctl: Add ARCH_[GET|SET]_CPUID
2017-03-20 16:10:34 +01:00
Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
2017-05-09 09:12:53 -07:00
fhandle: move compat syscalls from compat.c
2017-04-17 12:52:26 -04:00
mm, vmalloc: use __GFP_HIGHMEM implicitly
2017-05-08 17:15:13 -07:00
fs: new infrastructure for writeback error handling and reporting
2017-07-06 07:02:25 -04:00
Replace <asm/uaccess.h> with <linux/uaccess.h> globally
2016-12-24 11:46:01 -08:00
writeback: fix memory leak in wb_queue_work()
2017-03-13 08:27:34 -06:00
sched/headers: Prepare for new header dependencies before moving code to <linux/sched/task.h>
2017-03-02 08:42:35 +01:00
Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
2017-05-09 09:12:53 -07:00
Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
2017-05-09 09:12:53 -07:00
sched/headers: Prepare for the reduction of <linux/sched.h>'s signal API dependency
2017-03-02 08:42:37 +01:00
fs: semove set but not checked AOP_FLAG_UNINTERRUPTIBLE flag
2017-05-08 17:15:14 -07:00
block, dax: move "select DAX" from BLOCK to FS_DAX
2017-05-08 10:55:27 -07:00
docs: fix locations of several documents that got moved
2016-10-24 08:12:35 -02:00
fs: check for writeback errors after syncing out buffers in generic_file_fsync
2017-07-06 07:02:21 -04:00
locks: Set FL_CLOSE when removing flock locks on close()
2017-04-21 10:45:01 -04:00
logfs: remove from tree
2016-12-14 23:48:11 -05:00
mbcache: document that "find" functions only return reusable entries
2016-12-03 15:55:01 -05:00
fsnotify: Free fsnotify_mark_connector when there is no mark attached
2017-04-10 17:37:35 +02:00
fs: add i_blocksize()
2017-02-27 18:43:46 -08:00
Merge branch 'work.sane_pwd' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
2017-05-12 11:39:59 -07:00
Merge branch 'work.sane_pwd' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
2017-05-12 11:39:59 -07:00
ns: allow ns_entries to have custom symlink content
2017-05-08 17:15:12 -07:00
fs: new infrastructure for writeback error handling and reporting
2017-07-06 07:02:25 -04:00
Replace <asm/uaccess.h> with <linux/uaccess.h> globally
2016-12-24 11:46:01 -08:00
mnt: Tuck mounts under others instead of creating shadow/side mounts.
2017-02-04 00:01:06 +13:00
mnt: Tuck mounts under others instead of creating shadow/side mounts.
2017-02-04 00:01:06 +13:00
sched/headers: Prepare to remove <linux/cred.h> inclusion from <linux/sched.h>
2017-03-02 08:42:31 +01:00
sched/headers: Prepare to move the task_lock()/unlock() APIs to <linux/sched/task.h>
2017-03-02 08:42:38 +01:00
move compat_rw_copy_check_uvector() over to fs/read_write.c
2017-04-17 12:52:26 -04:00
readdir: move compat syscalls from compat.c
2017-04-17 12:52:24 -04:00
treewide: use kv[mz]alloc* rather than opencoded variants
2017-05-08 17:15:13 -07:00
mm: introduce kv[mz]alloc helpers
2017-05-08 17:15:12 -07:00
mm: Rename SLAB_DESTROY_BY_RCU to SLAB_TYPESAFE_BY_RCU
2017-04-18 11:42:36 -07:00
Merge branch 'work.splice' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
2017-05-02 11:38:06 -07:00
Merge branch 'work.compat' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
2017-05-02 11:54:26 -07:00
statfs: move compat syscalls from compat.c
2017-04-17 12:52:23 -04:00
bdi: Drop 'parent' argument from bdi_register[_va]()
2017-04-20 12:09:55 -06:00
vfs: use helper for calling f_op->fsync()
2017-02-20 16:51:23 +01:00
timerfd: Only check CAP_WAKE_ALARM when it is needed
2017-03-01 12:53:44 +01:00
userfaultfd: report actual registered features in fdinfo
2017-04-08 00:47:48 -07:00
utimes: move compat syscalls from compat.c
2017-04-17 12:52:23 -04:00
treewide: use kv[mz]alloc* rather than opencoded variants
2017-05-08 17:15:13 -07:00
5660e13d2f