Here is the large set of driver core changes for 6.3-rc1.
There's a lot of changes this development cycle, most of the work falls
into two different categories:
- fw_devlink fixes and updates. This has gone through numerous review
cycles and lots of review and testing by lots of different devices.
Hopefully all should be good now, and Saravana will be keeping a
watch for any potential regression on odd embedded systems.
- driver core changes to work to make struct bus_type able to be moved
into read-only memory (i.e. const) The recent work with Rust has
pointed out a number of areas in the driver core where we are
passing around and working with structures that really do not have
to be dynamic at all, and they should be able to be read-only making
things safer overall. This is the contuation of that work (started
last release with kobject changes) in moving struct bus_type to be
constant. We didn't quite make it for this release, but the
remaining patches will be finished up for the release after this
one, but the groundwork has been laid for this effort.
Other than that we have in here:
- debugfs memory leak fixes in some subsystems
- error path cleanups and fixes for some never-able-to-be-hit
codepaths.
- cacheinfo rework and fixes
- Other tiny fixes, full details are in the shortlog
All of these have been in linux-next for a while with no reported
problems.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-6.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core updates from Greg KH:
"Here is the large set of driver core changes for 6.3-rc1.
There's a lot of changes this development cycle, most of the work
falls into two different categories:
- fw_devlink fixes and updates. This has gone through numerous review
cycles and lots of review and testing by lots of different devices.
Hopefully all should be good now, and Saravana will be keeping a
watch for any potential regression on odd embedded systems.
- driver core changes to work to make struct bus_type able to be
moved into read-only memory (i.e. const) The recent work with Rust
has pointed out a number of areas in the driver core where we are
passing around and working with structures that really do not have
to be dynamic at all, and they should be able to be read-only
making things safer overall. This is the contuation of that work
(started last release with kobject changes) in moving struct
bus_type to be constant. We didn't quite make it for this release,
but the remaining patches will be finished up for the release after
this one, but the groundwork has been laid for this effort.
Other than that we have in here:
- debugfs memory leak fixes in some subsystems
- error path cleanups and fixes for some never-able-to-be-hit
codepaths.
- cacheinfo rework and fixes
- Other tiny fixes, full details are in the shortlog
All of these have been in linux-next for a while with no reported
problems"
[ Geert Uytterhoeven points out that that last sentence isn't true, and
that there's a pending report that has a fix that is queued up - Linus ]
* tag 'driver-core-6.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (124 commits)
debugfs: drop inline constant formatting for ERR_PTR(-ERROR)
OPP: fix error checking in opp_migrate_dentry()
debugfs: update comment of debugfs_rename()
i3c: fix device.h kernel-doc warnings
dma-mapping: no need to pass a bus_type into get_arch_dma_ops()
driver core: class: move EXPORT_SYMBOL_GPL() lines to the correct place
Revert "driver core: add error handling for devtmpfs_create_node()"
Revert "devtmpfs: add debug info to handle()"
Revert "devtmpfs: remove return value of devtmpfs_delete_node()"
driver core: cpu: don't hand-override the uevent bus_type callback.
devtmpfs: remove return value of devtmpfs_delete_node()
devtmpfs: add debug info to handle()
driver core: add error handling for devtmpfs_create_node()
driver core: bus: update my copyright notice
driver core: bus: add bus_get_dev_root() function
driver core: bus: constify bus_unregister()
driver core: bus: constify some internal functions
driver core: bus: constify bus_get_kset()
driver core: bus: constify bus_register/unregister_notifier()
driver core: remove private pointer from struct bus_type
...
Add a new SDF_DEACTIVATING super block flag that is set when the
filesystem has started to deactivate. This will be used in the next
patch to stop and drain the delete work during unmount.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
The uevent() callback in struct kset_uevent_ops does not modify the
kobject passed into it, so make the pointer const to enforce this
restriction. When doing so, fix up all existing uevent() callbacks to
have the correct signature to preserve the build.
Cc: Christine Caulfield <ccaulfie@redhat.com>
Cc: David Teigland <teigland@redhat.com>
Cc: Bob Peterson <rpeterso@redhat.com>
Cc: Andreas Gruenbacher <agruenba@redhat.com>
Acked-by: Rafael J. Wysocki <rafael@kernel.org>
Acked-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20230111113018.459199-17-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There is no good reason to keep genhd.h separate from the main blkdev.h
header that includes it. So fold the contents of genhd.h into blkdev.h
and remove genhd.h entirely.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20220124093913.742411-4-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
There is no need to pass the pointer to the kset in the struct
kset_uevent_ops callbacks as no one uses it, so just remove that pointer
entirely.
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Wedson Almeida Filho <wedsonaf@google.com>
Link: https://lore.kernel.org/r/20211227163924.3970661-1-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch adds a new file: /sys/fs/gfs2/*/status which will report
the status of the file system. Catting this file dumps the current
status of the file system according to various superblock variables.
For example:
Journal Checked: 1
Journal Live: 1
Journal ID: 0
Spectator: 0
Withdrawn: 0
No barriers: 0
No recovery: 0
Demote: 0
No Journal ID: 1
Mounted RO: 0
RO Recovery: 0
Skip DLM Unlock: 0
Force AIL Flush: 0
FS Frozen: 0
Withdrawing: 0
Withdraw In Prog: 0
Remote Withdraw: 0
Withdraw Recovery: 0
sd_log_error: 0
sd_log_flush_lock: 0
sd_log_num_revoke: 0
sd_log_in_flight: 0
sd_log_blks_needed: 0
sd_log_blks_free: 32768
sd_log_flush_head: 0
sd_log_flush_tail: 5384
sd_log_blks_reserved: 0
sd_log_revokes_available: 503
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
syzkaller found the following splat with CONFIG_DEBUG_KOBJECT_RELEASE=y:
Read of size 1 at addr ffff000028e896b8 by task kworker/1:2/228
CPU: 1 PID: 228 Comm: kworker/1:2 Tainted: G S 5.9.0-rc8+ #101
Hardware name: linux,dummy-virt (DT)
Workqueue: events kobject_delayed_cleanup
Call trace:
dump_backtrace+0x0/0x4d8
show_stack+0x34/0x48
dump_stack+0x174/0x1f8
print_address_description.constprop.0+0x5c/0x550
kasan_report+0x13c/0x1c0
__asan_report_load1_noabort+0x34/0x60
memcmp+0xd0/0xd8
gfs2_uevent+0xc4/0x188
kobject_uevent_env+0x54c/0x1240
kobject_uevent+0x2c/0x40
__kobject_del+0x190/0x1d8
kobject_delayed_cleanup+0x2bc/0x3b8
process_one_work+0x96c/0x18c0
worker_thread+0x3f0/0xc30
kthread+0x390/0x498
ret_from_fork+0x10/0x18
Allocated by task 1110:
kasan_save_stack+0x28/0x58
__kasan_kmalloc.isra.0+0xc8/0xe8
kasan_kmalloc+0x10/0x20
kmem_cache_alloc_trace+0x1d8/0x2f0
alloc_super+0x64/0x8c0
sget_fc+0x110/0x620
get_tree_bdev+0x190/0x648
gfs2_get_tree+0x50/0x228
vfs_get_tree+0x84/0x2e8
path_mount+0x1134/0x1da8
do_mount+0x124/0x138
__arm64_sys_mount+0x164/0x238
el0_svc_common.constprop.0+0x15c/0x598
do_el0_svc+0x60/0x150
el0_svc+0x34/0xb0
el0_sync_handler+0xc8/0x5b4
el0_sync+0x15c/0x180
Freed by task 228:
kasan_save_stack+0x28/0x58
kasan_set_track+0x28/0x40
kasan_set_free_info+0x24/0x48
__kasan_slab_free+0x118/0x190
kasan_slab_free+0x14/0x20
slab_free_freelist_hook+0x6c/0x210
kfree+0x13c/0x460
Use the same pattern as f2fs + ext4 where the kobject destruction must
complete before allowing the FS itself to be freed. This means that we
need an explicit free_sbd in the callers.
Cc: Bob Peterson <rpeterso@redhat.com>
Cc: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Jamie Iles <jamie@nuviainc.com>
[Also go to fail_free when init_names fails.]
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
When a node withdraws from a file system, it often leaves its journal
in an incomplete state. This is especially true when the withdraw is
caused by io errors writing to the journal. Before this patch, a
withdraw would try to write a "shutdown" record to the journal, tell
dlm it's done with the file system, and none of the other nodes
know about the problem. Later, when the problem is fixed and the
withdrawn node is rebooted, it would then discover that its own
journal was incomplete, and replay it. However, replaying it at this
point is almost guaranteed to introduce corruption because the other
nodes are likely to have used affected resource groups that appeared
in the journal since the time of the withdraw. Replaying the journal
later will overwrite any changes made, and not through any fault of
dlm, which was instructed during the withdraw to release those
resources.
This patch makes file system withdraws seen by the entire cluster.
Withdrawing nodes dequeue their journal glock to allow recovery.
The remaining nodes check all the journals to see if they are
clean or in need of replay. They try to replay dirty journals, but
only the journals of withdrawn nodes will be "not busy" and
therefore available for replay.
Until the journal replay is complete, no i/o related glocks may be
given out, to ensure that the replay does not cause the
aforementioned corruption: We cannot allow any journal replay to
overwrite blocks associated with a glock once it is held.
The "live" glock which is now used to signal when a withdraw
occurs. When a withdraw occurs, the node signals its withdraw by
dequeueing the "live" glock and trying to enqueue it in EX mode,
thus forcing the other nodes to all see a demote request, by way
of a "1CB" (one callback) try lock. The "live" glock is not
granted in EX; the callback is only just used to indicate a
withdraw has occurred.
Note that all nodes in the cluster must wait for the recovering
node to finish replaying the withdrawing node's journal before
continuing. To this end, it checks that the journals are clean
multiple times in a retry loop.
Also note that the withdraw function may be called from a wide
variety of situations, and therefore, we need to take extra
precautions to make sure pointers are valid before using them in
many circumstances.
We also need to take care when glocks decide to withdraw, since
the withdraw code now uses glocks.
Also, before this patch, if a process encountered an error and
decided to withdraw, if another process was already withdrawing,
the second withdraw would be silently ignored, which set it free
to unlock its glocks. That's correct behavior if the original
withdrawer encounters further errors down the road. But if
secondary waiters don't wait for the journal replay, unlocking
glocks will allow other nodes to use them, despite the fact that
the journal containing those blocks is being replayed. The
replay needs to finish before our glocks are released to other
nodes. IOW, secondary withdraws need to wait for the first
withdraw to finish.
For example, if an rgrp glock is unlocked by a process that didn't
wait for the first withdraw, a journal replay could introduce file
system corruption by replaying a rgrp block that has already been
granted to a different cluster node.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Split gfs2_lm_withdraw into a function that prints an error message and a
function that withdraws the filesystem.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Add function gfs2_withdrawn and replace all checks for the SDF_WITHDRAWN
bit to call it. This does not change the logic or function of gfs2, and
it facilitates later improvements to the withdraw sequence.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Here is the "big" driver core and debugfs changes for 5.3-rc1
It's a lot of different patches, all across the tree due to some api
changes and lots of debugfs cleanups. Because of this, there is going
to be some merge issues with your tree at the moment, I'll follow up
with the expected resolutions to make it easier for you.
Other than the debugfs cleanups, in this set of changes we have:
- bus iteration function cleanups (will cause build warnings
with s390 and coresight drivers in your tree)
- scripts/get_abi.pl tool to display and parse Documentation/ABI
entries in a simple way
- cleanups to Documenatation/ABI/ entries to make them parse
easier due to typos and other minor things
- default_attrs use for some ktype users
- driver model documentation file conversions to .rst
- compressed firmware file loading
- deferred probe fixes
All of these have been in linux-next for a while, with a bunch of merge
issues that Stephen has been patient with me for. Other than the merge
issues, functionality is working properly in linux-next :)
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core and debugfs updates from Greg KH:
"Here is the "big" driver core and debugfs changes for 5.3-rc1
It's a lot of different patches, all across the tree due to some api
changes and lots of debugfs cleanups.
Other than the debugfs cleanups, in this set of changes we have:
- bus iteration function cleanups
- scripts/get_abi.pl tool to display and parse Documentation/ABI
entries in a simple way
- cleanups to Documenatation/ABI/ entries to make them parse easier
due to typos and other minor things
- default_attrs use for some ktype users
- driver model documentation file conversions to .rst
- compressed firmware file loading
- deferred probe fixes
All of these have been in linux-next for a while, with a bunch of
merge issues that Stephen has been patient with me for"
* tag 'driver-core-5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (102 commits)
debugfs: make error message a bit more verbose
orangefs: fix build warning from debugfs cleanup patch
ubifs: fix build warning after debugfs cleanup patch
driver: core: Allow subsystems to continue deferring probe
drivers: base: cacheinfo: Ensure cpu hotplug work is done before Intel RDT
arch_topology: Remove error messages on out-of-memory conditions
lib: notifier-error-inject: no need to check return value of debugfs_create functions
swiotlb: no need to check return value of debugfs_create functions
ceph: no need to check return value of debugfs_create functions
sunrpc: no need to check return value of debugfs_create functions
ubifs: no need to check return value of debugfs_create functions
orangefs: no need to check return value of debugfs_create functions
nfsd: no need to check return value of debugfs_create functions
lib: 842: no need to check return value of debugfs_create functions
debugfs: provide pr_fmt() macro
debugfs: log errors when something goes wrong
drivers: s390/cio: Fix compilation warning about const qualifiers
drivers: Add generic helper to match by of_node
driver_find_device: Unify the match function with class_find_device()
bus_find_device: Unify the match callback with class_find_device
...
Before this patch, the superblock flag indicating when a file system
is withdrawn was called SDF_SHUTDOWN. This patch simply renames it to
the more obvious SDF_WITHDRAWN.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Add a free_sbd function for freeing a struct gfs2_sbd. Use that for
freeing a super-block descriptor, either directly or via kobject_put.
Free sd_lkstats inside the kobject release function: that way,
gfs2_put_super will no longer leak sd_lkstats.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
The kobj_type default_attrs field is being replaced by the
default_groups field. Replace the default_attrs field in gfs2_ktype
with default_groups. Use the ATTRIBUTE_GROUPS macro to create
gfs2_groups.
Signed-off-by: Kimberly Brown <kimbrownkd@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Based on 1 normalized pattern(s):
this copyrighted material is made available to anyone wishing to use
modify copy or redistribute it subject to the terms and conditions
of the gnu general public license version 2
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 44 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190531081038.653000175@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If a call to kobject_init_and_add() fails we must call kobject_put()
otherwise we leak memory.
Function gfs2_sys_fs_add always calls kobject_init_and_add() which
always calls kobject_init().
It is safe to leave object destruction up to the kobject release
function and never free it manually.
Remove call to kfree() and always call kobject_put() in the error path.
Signed-off-by: Tobin C. Harding <tobin@kernel.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch fixes a couple problems dealing with spectators who
remain with gfs2 mounts after the last non-spectator node fails.
Before this patch, spectator mounts would try to acquire the dlm's
mounted lock EX as part of its normal recovery sequence.
The mounted lock is only used to determine whether the node is
the first mounter, the first node to mount the file system, for
the purposes of file system recovery and journal replay.
It's not necessary for spectators: they should never do journal
recovery. If they acquire the lock it will prevent another "real"
first-mounter from acquiring the lock in EX mode, which means it
also cannot do journal recovery because it doesn't think it's the
first node to mount the file system.
This patch checks if the mounter is a spectator, and if so, avoids
grabbing the mounted lock. This allows a secondary mounter who is
really the first non-spectator mounter, to do journal recovery:
since the spectator doesn't acquire the lock, it can grab it in
EX mode, and therefore consider itself to be the first mounter
both as a "real" first mount, and as a first-real-after-spectator.
Note that the control lock still needs to be taken in PR mode
in order to fetch the lvb value so it has the current status of
all journal's recovery. This is used as it is today by a first
mounter to replay the journals. For spectators, it's merely
used to fetch the status bits. All recovery is bypassed and the
node waits until recovery is completed by a non-spectator node.
I also improved the cryptic message given by control_mount when
a spectator is waiting for a non-spectator to perform recovery.
It also fixes a problem in gfs2_recover_set whereby spectators
were never queueing recovery work for their own journal.
They cannot do recovery themselves, but they still need to queue
the work so they can check the recovery bits and clear the
DFL_BLOCK_LOCKS bit once the recovery happens on another node.
When the work queue runs on a spectator, it bypasses most of the
work so it won't print a bunch of annoying messages. All it will
print is a bunch of messages that look like this until recovery
completes on the non-spectator node:
GFS2: fsid=mycluster:scratch.s: recover generation 3 jid 0
GFS2: fsid=mycluster:scratch.s: recover jid 0 result busy
These continue every 1.5 seconds until the recovery is done by
the non-spectator, at which time it says:
GFS2: fsid=mycluster:scratch.s: recover generation 4 done
Then it proceeds with its mount.
If the file system is mounted in spectator node and the last
remaining non-spectator is fenced, any IO to the file system is
blocked by dlm and the spectator waits until recovery is
performed by a non-spectator.
If a spectator tries to mount the file system before any
non-spectators, it blocks and repeatedly gives this kernel
message:
GFS2: fsid=mycluster:scratch: Recovery is required. Waiting for a non-spectator to mount.
GFS2: fsid=mycluster:scratch: Recovery is required. Waiting for a non-spectator to mount.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Some of the info, warning, and error messages are missing their trailing
newline.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Firstly by applying the following with coccinelle's spatch:
@@ expression SB; @@
-SB->s_flags & MS_RDONLY
+sb_rdonly(SB)
to effect the conversion to sb_rdonly(sb), then by applying:
@@ expression A, SB; @@
(
-(!sb_rdonly(SB)) && A
+!sb_rdonly(SB) && A
|
-A != (sb_rdonly(SB))
+A != sb_rdonly(SB)
|
-A == (sb_rdonly(SB))
+A == sb_rdonly(SB)
|
-!(sb_rdonly(SB))
+!sb_rdonly(SB)
|
-A && (sb_rdonly(SB))
+A && sb_rdonly(SB)
|
-A || (sb_rdonly(SB))
+A || sb_rdonly(SB)
|
-(sb_rdonly(SB)) != A
+sb_rdonly(SB) != A
|
-(sb_rdonly(SB)) == A
+sb_rdonly(SB) == A
|
-(sb_rdonly(SB)) && A
+sb_rdonly(SB) && A
|
-(sb_rdonly(SB)) || A
+sb_rdonly(SB) || A
)
@@ expression A, B, SB; @@
(
-(sb_rdonly(SB)) ? 1 : 0
+sb_rdonly(SB)
|
-(sb_rdonly(SB)) ? A : B
+sb_rdonly(SB) ? A : B
)
to remove left over excess bracketage and finally by applying:
@@ expression A, SB; @@
(
-(A & MS_RDONLY) != sb_rdonly(SB)
+(bool)(A & MS_RDONLY) != sb_rdonly(SB)
|
-(A & MS_RDONLY) == sb_rdonly(SB)
+(bool)(A & MS_RDONLY) == sb_rdonly(SB)
)
to make comparisons against the result of sb_rdonly() (which is a bool)
work correctly.
Signed-off-by: David Howells <dhowells@redhat.com>
1. Andreas Gruenbacher has four patches related to cleaning up the GFS2
inode evict process. This is about half of his patches designed to
fix a long-standing GFS2 hang related to the inode shrinker.
(Shrinker calls gfs2 evict, evict calls DLM, DLM requires memory
and blocks on the shrinker.) These 4 patches have been well tested.
His second set of patches are still being tested, so I plan to hold
them until the next merge window, after we have more weeks of testing.
The first patch eliminates the flush_delayed_work, which can block.
2. Andreas's second patch protects setting of gl_object for rgrps with
a spin_lock to prevent proven races.
3. His third patch introduces a centralized mechanism for queueing glock
work with better reference counting, to prevent more races.
4. His fourth patch retains a reference to inode glocks when an error
occurs while creating an inode. This keeps the subsequent evict from
needing to reacquire the glock, which might call into DLM and block
in low memory conditions.
5. Arvind Yadav has a patch to add const to attribute_group structures.
6. I have a patch to detect directory entry inconsistencies and withdraw
the file system if any are found. Better that than silent corruption.
7. I have a patch to remove a vestigial variable from glock structures,
saving some slab space.
8. I have another patch to remove a vestigial variable from the GFS2
in-core superblock structure.
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Merge tag 'gfs2-4.13.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2
Pull GFS2 updates from Bob Peterson:
"We've got eight GFS2 patches for this merge window:
- Andreas Gruenbacher has four patches related to cleaning up the
GFS2 inode evict process. This is about half of his patches
designed to fix a long-standing GFS2 hang related to the inode
shrinker: Shrinker calls gfs2 evict, evict calls DLM, DLM requires
memory and blocks on the shrinker.
These four patches have been well tested. His second set of patches
are still being tested, so I plan to hold them until the next merge
window, after we have more weeks of testing. The first patch
eliminates the flush_delayed_work, which can block.
- Andreas's second patch protects setting of gl_object for rgrps with
a spin_lock to prevent proven races.
- His third patch introduces a centralized mechanism for queueing
glock work with better reference counting, to prevent more races.
-His fourth patch retains a reference to inode glocks when an error
occurs while creating an inode. This keeps the subsequent evict
from needing to reacquire the glock, which might call into DLM and
block in low memory conditions.
- Arvind Yadav has a patch to add const to attribute_group
structures.
- I have a patch to detect directory entry inconsistencies and
withdraw the file system if any are found. Better that than silent
corruption.
- I have a patch to remove a vestigial variable from glock
structures, saving some slab space.
- I have another patch to remove a vestigial variable from the GFS2
in-core superblock structure"
* tag 'gfs2-4.13.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2:
GFS2: constify attribute_group structures.
gfs2: gfs2_create_inode: Keep glock across iput
gfs2: Clean up glock work enqueuing
gfs2: Protect gl->gl_object by spin lock
gfs2: Get rid of flush_delayed_work in gfs2_evict_inode
GFS2: Eliminate vestigial sd_log_flush_wrapped
GFS2: Remove gl_list from glock structure
GFS2: Withdraw when directory entry inconsistencies are detected
attribute_groups are not supposed to change at runtime. All functions
working with attribute_groups provided by <linux/sysfs.h> work with const
attribute_group. So mark the non-const structs as const.
File size before:
text data bss dec hex filename
5259 1344 8 6611 19d3 fs/gfs2/sys.o
File size After adding 'const':
text data bss dec hex filename
5371 1216 8 6595 19c3 fs/gfs2/sys.o
Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
For some file systems we still memcpy into it, but in various places this
already allows us to use the proper uuid helpers. More to come..
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Acked-by: Mimi Zohar <zohar@linux.vnet.ibm.com> (Changes to IMA/EVM)
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Add #include <linux/cred.h> dependencies to all .c files rely on sched.h
doing that for them.
Note that even if the count where we need to add extra headers seems high,
it's still a net win, because <linux/sched.h> is included in over
2,200 files ...
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This was entirely automated, using the script by Al:
PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>'
sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \
$(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)
to do the replacement at the end of the merge window.
Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-Remove obsolete simple_str functions.
-Return error code when kstr failed.
-This patch also calls functions corresponding to destination type.
Thanks to Alexey Dobriyan for suggesting improvements in
block_store() and wdack_store()
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Sprintf format specifier "%d" and "%u" are mixed up in
gfs2_recovery_done() and freeze_show(). So correct them.
Signed-off-by: Alex Chen <alex.chen@huawei.com>
Reviewed-by: Joseph Qi <joseph.qi@huawei.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
It is probably also the first one without a single patch from me. That
is down to a combination of factors, and I have some things in the works
that are not quite ready yet, that I hope to put in next time around.
Returning to what is here this time... we have 3 patches which fix
various warnings. Two are bug fixes (for quotas and also a
rare recovery race condition). The final patch, from Ben Marzinski,
is an important change in the freeze code which has been in
progress for some time. This removes the need to take and drop the
transaction lock for every single transaction, when the only time it
was used, was at file system freeze time. Ben's patch integrates the
freeze operation into the journal flush code as an alternative with
lower overheads and also lands up resolving some difficult to fix races
at the same time.
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Merge tag 'gfs2-merge-window' of git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-3.0-nmw into next
Pull gfs2 updates from Steven Whitehouse:
"This must be about the smallest merge window patch set ever for GFS2.
It is probably also the first one without a single patch from me.
That is down to a combination of factors, and I have some things in
the works that are not quite ready yet, that I hope to put in next
time around.
Returning to what is here this time... we have 3 patches which fix
various warnings. Two are bug fixes (for quotas and also a rare
recovery race condition). The final patch, from Ben Marzinski, is an
important change in the freeze code which has been in progress for
some time. This removes the need to take and drop the transaction
lock for every single transaction, when the only time it was used, was
at file system freeze time. Ben's patch integrates the freeze
operation into the journal flush code as an alternative with lower
overheads and also lands up resolving some difficult to fix races at
the same time"
* tag 'gfs2-merge-window' of git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-3.0-nmw:
GFS2: Prevent recovery before the local journal is set
GFS2: fs/gfs2/file.c: kernel-doc warning fixes
GFS2: fs/gfs2/bmap.c: kernel-doc warning fixes
GFS2: remove transaction glock
GFS2: lops.c: replace 0 by NULL for pointers
GFS2: quotas not being refreshed in gfs2_adjust_quota
This patch uses a completion to prevent dlm's recovery process from
referencing and trying to recover a journal before a journal has been
opened.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
GFS2 has a transaction glock, which must be grabbed for every
transaction, whose purpose is to deal with freezing the filesystem.
Aside from this involving a large amount of locking, it is very easy to
make the current fsfreeze code hang on unfreezing.
This patch rewrites how gfs2 handles freezing the filesystem. The
transaction glock is removed. In it's place is a freeze glock, which is
cached (but not held) in a shared state by every node in the cluster
when the filesystem is mounted. This lock only needs to be grabbed on
freezing, and actions which need to be safe from freezing, like
recovery.
When a node wants to freeze the filesystem, it grabs this glock
exclusively. When the freeze glock state changes on the nodes (either
from shared to unlocked, or shared to exclusive), the filesystem does a
special log flush. gfs2_log_flush() does all the work for flushing out
the and shutting down the incore log, and then it tries to grab the
freeze glock in a shared state again. Since the filesystem is stuck in
gfs2_log_flush, no new transaction can start, and nothing can be written
to disk. Unfreezing the filesytem simply involes dropping the freeze
glock, allowing gfs2_log_flush() to grab and then release the shared
lock, so it is cached for next time.
However, in order for the unfreezing ioctl to occur, gfs2 needs to get a
shared lock on the filesystem root directory inode to check permissions.
If that glock has already been grabbed exclusively, fsfreeze will be
unable to get the shared lock and unfreeze the filesystem.
In order to allow the unfreeze, this patch makes gfs2 grab a shared lock
on the filesystem root directory during the freeze, and hold it until it
unfreezes the filesystem. The functions which need to grab a shared
lock in order to allow the unfreeze ioctl to be issued now use the lock
grabbed by the freeze code instead.
The freeze and unfreeze code take care to make sure that this shared
lock will not be dropped while another process is using it.
Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
vprintk use is not prefixed by a KERN_<LEVEL>,
so emit these messages at KERN_ERR level.
Using %pV can save some code and allow fs_err to
be used, so do it.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Add pr_fmt, remove embedded "GFS2: " prefixes.
This now consistently emits lower case "gfs2: " for each message.
Other miscellanea around these changes:
o Add missing newlines
o Coalesce formats
o Realign arguments
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
There is no need for a paramater which relates to the internals
of quota to be exposed to users. The only possible use would be
to turn it up so large that the memory allocation fails. So lets
remove it and set it to a sensible value which ensures that we
don't ask for multipage allocations.
Currently the size of struct gfs2_holder means that the caluclated
value is identical to the previous default value, so there should
be no functional change.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Cc: Abhijith Das <adas@redhat.com>
Pull vfs pile (part one) from Al Viro:
"Assorted stuff - cleaning namei.c up a bit, fixing ->d_name/->d_parent
locking violations, etc.
The most visible changes here are death of FS_REVAL_DOT (replaced with
"has ->d_weak_revalidate()") and a new helper getting from struct file
to inode. Some bits of preparation to xattr method interface changes.
Misc patches by various people sent this cycle *and* ocfs2 fixes from
several cycles ago that should've been upstream right then.
PS: the next vfs pile will be xattr stuff."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (46 commits)
saner proc_get_inode() calling conventions
proc: avoid extra pde_put() in proc_fill_super()
fs: change return values from -EACCES to -EPERM
fs/exec.c: make bprm_mm_init() static
ocfs2/dlm: use GFP_ATOMIC inside a spin_lock
ocfs2: fix possible use-after-free with AIO
ocfs2: Fix oops in ocfs2_fast_symlink_readpage() code path
get_empty_filp()/alloc_file() leave both ->f_pos and ->f_version zero
target: writev() on single-element vector is pointless
export kernel_write(), convert open-coded instances
fs: encode_fh: return FILEID_INVALID if invalid fid_type
kill f_vfsmnt
vfs: kill FS_REVAL_DOT by adding a d_weak_revalidate dentry op
nfsd: handle vfs_getattr errors in acl protocol
switch vfs_getattr() to struct path
default SET_PERSONALITY() in linux/elf.h
ceph: prepopulate inodes only when request is aborted
d_hash_and_lookup(): export, switch open-coded instances
9p: switch v9fs_set_create_acl() to inode+fid, do it before d_instantiate()
9p: split dropping the acls from v9fs_set_create_acl()
...
According to SUSv3:
[EACCES] Permission denied. An attempt was made to access a file in a way
forbidden by its file access permissions.
[EPERM] Operation not permitted. An attempt was made to perform an operation
limited to processes with appropriate privileges or to the owner of a file
or other resource.
So -EPERM should be returned if capability checks fails.
Strictly speaking this is an API change since the error code user sees is
altered.
Signed-off-by: Zhao Hongjiang <zhaohongjiang@huawei.com>
Acked-by: Jan Kara <jack@suse.cz>
Acked-by: Steven Whitehouse <swhiteho@redhat.com>
Acked-by: Ian Kent <raven@themaw.net>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Pull user namespace and namespace infrastructure changes from Eric W Biederman:
"This set of changes starts with a few small enhnacements to the user
namespace. reboot support, allowing more arbitrary mappings, and
support for mounting devpts, ramfs, tmpfs, and mqueuefs as just the
user namespace root.
I do my best to document that if you care about limiting your
unprivileged users that when you have the user namespace support
enabled you will need to enable memory control groups.
There is a minor bug fix to prevent overflowing the stack if someone
creates way too many user namespaces.
The bulk of the changes are a continuation of the kuid/kgid push down
work through the filesystems. These changes make using uids and gids
typesafe which ensures that these filesystems are safe to use when
multiple user namespaces are in use. The filesystems converted for
3.9 are ceph, 9p, afs, ocfs2, gfs2, ncpfs, nfs, nfsd, and cifs. The
changes for these filesystems were a little more involved so I split
the changes into smaller hopefully obviously correct changes.
XFS is the only filesystem that remains. I was hoping I could get
that in this release so that user namespace support would be enabled
with an allyesconfig or an allmodconfig but it looks like the xfs
changes need another couple of days before it they are ready."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (93 commits)
cifs: Enable building with user namespaces enabled.
cifs: Convert struct cifs_ses to use a kuid_t and a kgid_t
cifs: Convert struct cifs_sb_info to use kuids and kgids
cifs: Modify struct smb_vol to use kuids and kgids
cifs: Convert struct cifsFileInfo to use a kuid
cifs: Convert struct cifs_fattr to use kuid and kgids
cifs: Convert struct tcon_link to use a kuid.
cifs: Modify struct cifs_unix_set_info_args to hold a kuid_t and a kgid_t
cifs: Convert from a kuid before printing current_fsuid
cifs: Use kuids and kgids SID to uid/gid mapping
cifs: Pass GLOBAL_ROOT_UID and GLOBAL_ROOT_GID to keyring_alloc
cifs: Use BUILD_BUG_ON to validate uids and gids are the same size
cifs: Override unmappable incoming uids and gids
nfsd: Enable building with user namespaces enabled.
nfsd: Properly compare and initialize kuids and kgids
nfsd: Store ex_anon_uid and ex_anon_gid as kuids and kgids
nfsd: Modify nfsd4_cb_sec to use kuids and kgids
nfsd: Handle kuids and kgids in the nfs4acl to posix_acl conversion
nfsd: Convert nfsxdr to use kuids and kgids
nfsd: Convert nfs3xdr to use kuids and kgids
...
- In quota_refresh_user_store convert the user supplied uid
into a kqid and pass it to gfs2_quota_refresh.
- In quota_refresh_group_store convert the user supplied gid
into a kqid and pass it to gfs2_quota_refresh.
Cc: Steven Whitehouse <swhiteho@redhat.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
This patch reinstates the ack system which withdraw should be using. It
appears to have been accidentally forgotten when the lock module was
merged into GFS2, due to two different sysfs files having the same name.
Reported-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
The freeze code has not been looked at a lot recently. Upstream has
moved on, and this is an attempt to catch us back up again. There
is a vfs level interface for the freeze code which can be called
from our (obsolete, but kept for backward compatibility purposes)
sysfs freeze interface. This means freezing this way vs. doing it
from the ioctl should now work in identical fashion.
As a result of this, the freeze function is only called once
and we can drop our own special purpose code for counting the
number of freezes.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Pull GFS2 updates from Steven Whitehouse.
* git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-3.0-nmw:
GFS2: Eliminate 64-bit divides
GFS2: Reduce file fragmentation
GFS2: kernel panic with small gfs2 filesystems - 1 RG
GFS2: Fixing double brelse'ing bh allocated in gfs2_meta_read when EIO occurs
GFS2: Combine functions get_local_rgrp and gfs2_inplace_reserve
GFS2: Add kobject release method
GFS2: Size seq_file buffer more carefully
GFS2: Use seq_vprintf for glocks debugfs file
seq_file: Add seq_vprintf function and export it
GFS2: Use lvbs for storing rgrp information with mount option
GFS2: Cache last hash bucket for glock seq_files
GFS2: Increase buffer size for glocks and glstats debugfs files
GFS2: Fix error handling when reading an invalid block from the journal
GFS2: Add "top dir" flag support
GFS2: Fold quota data into the reservations struct
GFS2: Extend the life of the reservations
Split off part of dquot_quota_sync() which writes dquots into a quota file
to a separate function. In the next patch we will use the function from
filesystems and we do not want to abuse ->quota_sync quotactl callback more
than necessary.
Acked-by: Steven Whitehouse <swhiteho@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This patch adds a kobject release function that properly maintains
the kobject use count, so that accesses to the sysfs files do not
cause an access to freed kernel memory after an unmount.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Journal recovery from lock_dlm should not be ignored
if there is an unmount in progress. Ignoring it will
causes the recovery to get stuck. The recovery
process will correctly handle an in-progess unmount.
Signed-off-by: David Teigland <teigland@redhat.com>
This new method of managing recovery is an alternative to
the previous approach of using the userland gfs_controld.
- use dlm slot numbers to assign journal id's
- use dlm recovery callbacks to initiate journal recovery
- use a dlm lock to determine the first node to mount fs
- use a dlm lock to track journals that need recovery
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
There is a potential race during filesystem mounting which has recently
been reported. It occurs when the userland gfs_controld is able to
process requests fast enough that it tries to use the sysfs interface
before the lock module is properly initialised. This is a pretty
unusual case as normally the lock module initialisation is very quick
compared with gfs_controld.
This patch adds an interruptible completion which is used to ensure that
userland will wait for the initialisation of the lock module to
complete.
There are other potential solutions to this problem, but this is the
quickest at this stage and has been tested both with and without
mount.gfs2 present in the system.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Reported-by: David Booher <dbooher@adams.net>
The VFS superblock structure now has a UUID field, so we can use that
in preference to the UUID field in the GFS2 superblock now.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Mostly the glock operations follow the type of the glock. The
one exception is the transaction glock, so we need to check for
that directly.
Reported-by: Dr. David Alan Gilbert <linux@treblig.org>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Recently a feature was added to GFS2 to allow journal id allocation
via sysfs. This patch builds upon that so that a negative journal id
will be treated as an error code to be passed back as the return code
from mount. This allows termination of the mount process if there is
a failure.
Also, the process has been updated so that the kernel will wait
for a journal id, even in the "spectator" case. This is required
in order to avoid mounting a filesystem in case there is an error
while joining the cluster. In the spectator case, 0 is written into
the file to indicate that all is well, and that mount should continue.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq: (55 commits)
workqueue: mark init_workqueues() as early_initcall()
workqueue: explain for_each_*cwq_cpu() iterators
fscache: fix build on !CONFIG_SYSCTL
slow-work: kill it
gfs2: use workqueue instead of slow-work
drm: use workqueue instead of slow-work
cifs: use workqueue instead of slow-work
fscache: drop references to slow-work
fscache: convert operation to use workqueue instead of slow-work
fscache: convert object to use workqueue instead of slow-work
workqueue: fix how cpu number is stored in work->data
workqueue: fix mayday_mask handling on UP
workqueue: fix build problem on !CONFIG_SMP
workqueue: fix locking in retry path of maybe_create_worker()
async: use workqueue for worker pool
workqueue: remove WQ_SINGLE_CPU and use WQ_UNBOUND instead
workqueue: implement unbound workqueue
workqueue: prepare for WQ_UNBOUND implementation
libata: take advantage of cmwq and remove concurrency limitations
workqueue: fix worker management invocation without pending works
...
Fixed up conflicts in fs/cifs/* as per Tejun. Other trivial conflicts in
include/linux/workqueue.h, kernel/trace/Kconfig and kernel/workqueue.c
This patch implements a wait for the journal id in the case that it has
not been specified on the command line. This is to allow the future
removal of the mount.gfs2 helper. The journal id would instead be
directly communicated by gfs_controld to the file system. Here is a
comparison of the two systems:
Current:
1. mount calls mount.gfs2
2. mount.gfs2 connects to gfs_controld to retrieve the journal id
3. mount.gfs2 adds the journal id to the mount command line and calls
the mount system call
4. gfs_controld receives the status of the mount request via a uevent
Proposed:
1. mount calls the mount system call (no mount.gfs2 helper)
2. gfs_controld receives a uevent for a gfs2 fs which it doesn't know
about already
3. gfs_controld assigns a journal id to it via sysfs
4. the mount system call then completes as normal (sending a uevent
according to status)
The advantage of the proposed system is that it is completely backward
compatible with the current system both at the kernel and at the
userland levels. The "first" parameter can also be set the same way,
with the restriction that it must be set before the journal id is
assigned.
In addition, if mount becomes stuck waiting for a reply from
gfs_controld which never arrives, then it is killable and will abort the
mount gracefully.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
