Damien Le Moal [Wed, 11 Aug 2021 03:37:02 +0000 (12:37 +0900)]
block: fix default IO priority handling
The default IO priority is the best effort (BE) class with the
normal priority level IOPRIO_NORM (4). However, get_task_ioprio()
returns IOPRIO_CLASS_NONE/IOPRIO_NORM as the default priority and
get_current_ioprio() returns IOPRIO_CLASS_NONE/0. Let's be consistent
with the defined default and have both of these functions return the
default priority IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, IOPRIO_NORM) when
the user did not define another default IO priority for the task.
In include/uapi/linux/ioprio.h, introduce the IOPRIO_BE_NORM macro as
an alias to IOPRIO_NORM to clarify that this default level applies to
the BE priotity class. In include/linux/ioprio.h, define the macro
IOPRIO_DEFAULT as IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, IOPRIO_BE_NORM)
and use this new macro when setting a priority to the default.
Damien Le Moal [Wed, 11 Aug 2021 03:37:01 +0000 (12:37 +0900)]
block: Introduce IOPRIO_NR_LEVELS
The BFQ scheduler and ioprio_check_cap() both assume that the RT
priority class (IOPRIO_CLASS_RT) can have up to 8 different priority
levels, similarly to the BE class (IOPRIO_CLASS_iBE). This is
controlled using the IOPRIO_BE_NR macro , which is badly named as the
number of levels also applies to the RT class.
Introduce the class independent IOPRIO_NR_LEVELS macro, defined to 8,
to make things clear. Keep the old IOPRIO_BE_NR macro definition as an
alias for IOPRIO_NR_LEVELS.
Damien Le Moal [Wed, 11 Aug 2021 03:37:00 +0000 (12:37 +0900)]
block: fix IOPRIO_PRIO_CLASS() and IOPRIO_PRIO_VALUE() macros
The ki_ioprio field of struct kiocb is 16-bits (u16) but often handled
as an int in the block layer. E.g. ioprio_check_cap() takes an int as
argument.
With such implicit int casting function calls, the upper 16-bits of the
int argument may be left uninitialized by the compiler, resulting in
invalid values for the IOPRIO_PRIO_CLASS() macro (garbage upper bits)
and in an error return for functions such as ioprio_check_cap().
Fix this by masking the result of the shift by IOPRIO_CLASS_SHIFT bits
in the IOPRIO_PRIO_CLASS() macro. The new macro IOPRIO_CLASS_MASK
defines the 3-bits mask for the priority class.
Similarly, apply the IOPRIO_PRIO_MASK mask to the data argument of the
IOPRIO_PRIO_VALUE() macro to ignore the upper bits of the data value.
The IOPRIO_CLASS_MASK mask is also applied to the class argument of this
macro before shifting the result by IOPRIO_CLASS_SHIFT bits.
While at it, also change the argument name of the IOPRIO_PRIO_CLASS()
and IOPRIO_PRIO_DATA() macros from "mask" to "ioprio" to reflect the
fact that a priority value should be passed rather than a mask.
Damien Le Moal [Wed, 11 Aug 2021 03:36:59 +0000 (12:36 +0900)]
block: change ioprio_valid() to an inline function
Change the ioprio_valid() macro in include/usapi/linux/ioprio.h to an
inline function declared on the kernel side in include/linux/ioprio.h.
Also improve checks on the class value by checking the upper bound
value.
Damien Le Moal [Wed, 11 Aug 2021 03:36:58 +0000 (12:36 +0900)]
block: improve ioprio class description comment
In include/usapi/linux/ioprio.h, change the ioprio class enum comment
to remove the outdated reference to CFQ and mention BFQ and mq-deadline
instead. Also document the high priority NCQ command use for RT class
IOs directed at ATA drives that support NCQ priority.
Damien Le Moal [Wed, 11 Aug 2021 03:36:57 +0000 (12:36 +0900)]
block: bfq: fix bfq_set_next_ioprio_data()
For a request that has a priority level equal to or larger than
IOPRIO_BE_NR, bfq_set_next_ioprio_data() prints a critical warning but
defaults to setting the request new_ioprio field to IOPRIO_BE_NR. This
is not consistent with the warning and the allowed values for priority
levels. Fix this by setting the request new_ioprio field to
IOPRIO_BE_NR - 1, the lowest priority level allowed.
Cc: <stable@vger.kernel.org> Fixes: aee69d78dec0 ("block, bfq: introduce the BFQ-v0 I/O scheduler as an extra scheduler") Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Link: https://lore.kernel.org/r/20210811033702.368488-2-damien.lemoal@wdc.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
Use bvec_virt instead of open coding it. Note that the existing code is
fine despite ignoring bv_offset as the bio is known to contain exactly
one page from the page allocator per bio_vec.
block: ensure the bdi is freed after inode_detach_wb
inode_detach_wb references the "main" bdi of the inode. With the
recent change to move the bdi from the request_queue to the gendisk
this causes a guaranteed use after free when using certain cgroup
configurations. The big itself is older through as any non-default
inode reference (e.g. an open file descriptor) could have injected
this use after free even before that.
Fixes: 52ebea749aae ("writeback: make backing_dev_info host cgroup-specific bdi_writebacks") Reported-by: Qian Cai <quic_qiancai@quicinc.com> Reported-by: syzbot <syzbot+1fb38bb7d3ce0fa3e1c4@syzkaller.appspotmail.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20210816122614.601358-3-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
The dev_t is used as the inode hash, so we should only released it
once then block device inode is gone from the inode cache. Move it
to bdev_free_inode to ensure that.
Chunguang Xu [Mon, 2 Aug 2021 03:51:56 +0000 (11:51 +0800)]
blk-throtl: optimize IOPS throttle for large IO scenarios
After patch 54efd50 (block: make generic_make_request handle
arbitrarily sized bios), the IO through io-throttle may be larger,
and these IOs may be further split into more small IOs. However,
IOPS throttle does not seem to be aware of this change, which
makes the calculation of IOPS of large IOs incomplete, resulting
in disk-side IOPS that does not meet expectations. Maybe we should
fix this problem.
We can reproduce it by set max_sectors_kb of disk to 128, set
blkio.write_iops_throttle to 100, run a dd instance inside blkio
and use iostat to watch IOPS:
block: store a gendisk in struct parsed_partitions
Partition scanning only happens on the whole device, so pass a
struct gendisk instead of the whole device block_device to the scanners.
This allows to simplify printing the device name in various places as the
disk name is available in disk->name.
bcache: move the del_gendisk call out of bcache_device_free
Let the callers call del_gendisk so that we can check if add_disk
has been called properly for the cached device case instead of relying
on the block layer internal GENHD_FL_UP flag.
Ming Lei [Thu, 29 Jul 2021 03:42:26 +0000 (11:42 +0800)]
block: return ELEVATOR_DISCARD_MERGE if possible
When merging one bio to request, if they are discard IO and the queue
supports multi-range discard, we need to return ELEVATOR_DISCARD_MERGE
because both block core and related drivers(nvme, virtio-blk) doesn't
handle mixed discard io merge(traditional IO merge together with
discard merge) well.
Fix the issue by returning ELEVATOR_DISCARD_MERGE in this situation,
so both blk-mq and drivers just need to handle multi-range discard.
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Link: https://lore.kernel.org/r/20210809141744.1203023-6-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
block: move the bdi from the request_queue to the gendisk
The backing device information only makes sense for file system I/O,
and thus belongs into the gendisk and not the lower level request_queue
structure. Move it there.
Add a helper to check if a gendisk is associated with a request_queue.
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Link: https://lore.kernel.org/r/20210809141744.1203023-4-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
block: pass a gendisk to blk_queue_update_readahead
.. and rename the function to disk_update_readahead. This is in
preparation for moving the BDI from the request_queue to the gendisk.
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Link: https://lore.kernel.org/r/20210809141744.1203023-3-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
mm: hide laptop_mode_wb_timer entirely behind the BDI API
Don't leak the detaіls of the timer into the block layer, instead
initialize the timer in bdi_alloc and delete it in bdi_unregister.
Note that this means the timer is initialized (but not armed) for
non-block queues as well now.
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Link: https://lore.kernel.org/r/20210809141744.1203023-2-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
device mapper is currently the only outlier that tries to call
register_disk after add_disk, leading to fairly inconsistent state
of these block layer data structures. Instead change device-mapper
to just register the gendisk later now that the holder mechanism
can cope with that.
Note that this introduces a user visible change: the dm kobject is
now only visible after the initial table has been loaded.
Move setting md->type from both callers into dm_setup_md_queue.
This ensures that md->type is only set to a valid value after the queue
has been fully setup, something we'll rely on future changes.
device mapper needs to register holders before it is ready to do I/O.
Currently it does so by registering the disk early, which can leave
the disk and queue in a weird half state where the queue is registered
with the disk, except for sysfs and the elevator. And this state has
been a bit promlematic before, and will get more so when sorting out
the responsibilities between the queue and the disk.
Support registering holders on an initialized but not registered disk
instead by delaying the sysfs registration until the disk is registered.
block: remove the extra kobject reference in bd_link_disk_holder
Since commit 0d02129e76ed ("block: merge struct block_device and struct
hd_struct") there is no way for the bdev to go away as long as there is
a holder, so remove the extra references.
Move the block holder code into a separate file as it is not in any way
related to the other block_dev.c code, and add a new selectable config
option for it so that we don't have to build it without any remapped
drivers selected.
The Kconfig symbol contains a _DEPRECATED suffix to match the comments
added in commit 49731baa41df
("block: restore multiple bd_link_disk_holder() support").
Bart Van Assche [Thu, 5 Aug 2021 17:42:00 +0000 (10:42 -0700)]
loop: Select I/O scheduler 'none' from inside add_disk()
We noticed that the user interface of Android devices becomes very slow
under memory pressure. This is because Android uses the zram driver on top
of the loop driver for swapping, because under memory pressure the swap
code alternates reads and writes quickly, because mq-deadline is the
default scheduler for loop devices and because mq-deadline delays writes by
five seconds for such a workload with default settings. Fix this by making
the kernel select I/O scheduler 'none' from inside add_disk() for loop
devices. This default can be overridden at any time from user space,
e.g. via a udev rule. This approach has an advantage compared to changing
the I/O scheduler from userspace from 'mq-deadline' into 'none', namely
that synchronize_rcu() does not get called.
This patch changes the default I/O scheduler for loop devices from
'mq-deadline' into 'none'.
Additionally, this patch reduces the Android boot time on my test setup
with 0.5 seconds compared to configuring the loop I/O scheduler from user
space.
Cc: Christoph Hellwig <hch@lst.de> Cc: Ming Lei <ming.lei@redhat.com> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Martijn Coenen <maco@android.com> Cc: Jaegeuk Kim <jaegeuk@kernel.org> Signed-off-by: Bart Van Assche <bvanassche@acm.org> Link: https://lore.kernel.org/r/20210805174200.3250718-3-bvanassche@acm.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
Bart Van Assche [Thu, 5 Aug 2021 17:41:59 +0000 (10:41 -0700)]
blk-mq: Introduce the BLK_MQ_F_NO_SCHED_BY_DEFAULT flag
elevator_get_default() uses the following algorithm to select an I/O
scheduler from inside add_disk():
- In case of a single hardware queue or if sharing hardware queues across
multiple request queues (BLK_MQ_F_TAG_HCTX_SHARED), use mq-deadline.
- Otherwise, use 'none'.
This is a good choice for most but not for all block drivers. Make it
possible to override the selection of mq-deadline with a new flag,
namely BLK_MQ_F_NO_SCHED_BY_DEFAULT.
Cc: Christoph Hellwig <hch@lst.de> Cc: Ming Lei <ming.lei@redhat.com> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Martijn Coenen <maco@android.com> Cc: Jaegeuk Kim <jaegeuk@kernel.org> Signed-off-by: Bart Van Assche <bvanassche@acm.org> Link: https://lore.kernel.org/r/20210805174200.3250718-2-bvanassche@acm.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
Damien Le Moal [Tue, 13 Jul 2021 08:18:37 +0000 (17:18 +0900)]
block: remove blk-mq-sysfs dead code
In block/blk-mq-sysfs.c, struct blk_mq_ctx_sysfs_entry is not used to
define any attribute since the "mq" sysfs directory contains only
sub-directories (no attribute files). As a result, blk_mq_sysfs_show(),
blk_mq_sysfs_store(), and struct sysfs_ops blk_mq_sysfs_ops are all
unused and unnecessary. Remove all this unused code.
block: add a helper to raise a media changed event
Refactor disk_check_events() and move some code into disk_event_uevent().
Then add disk_force_media_change(), a helper which will be used by
devices to force issuing a DISK_EVENT_MEDIA_CHANGE event.
Associating uevents with block devices in userspace is difficult and racy:
the uevent netlink socket is lossy, and on slow and overloaded systems
has a very high latency.
Block devices do not have exclusive owners in userspace, any process can
set one up (e.g. loop devices). Moreover, device names can be reused
(e.g. loop0 can be reused again and again). A userspace process setting
up a block device and watching for its events cannot thus reliably tell
whether an event relates to the device it just set up or another earlier
instance with the same name.
Being able to set a UUID on a loop device would solve the race conditions.
But it does not allow to derive orderings from uevents: if you see a
uevent with a UUID that does not match the device you are waiting for,
you cannot tell whether it's because the right uevent has not arrived yet,
or it was already sent and you missed it. So you cannot tell whether you
should wait for it or not.
Associating a unique, monotonically increasing sequential number to the
lifetime of each block device, which can be retrieved with an ioctl
immediately upon setting it up, allows to solve the race conditions with
uevents, and also allows userspace processes to know whether they should
wait for the uevent they need or if it was dropped and thus they should
move on.
Additionally, increment the disk sequence number when the media change,
i.e. on DISK_EVENT_MEDIA_CHANGE event.
I have compiled the kernel with a cross compiler "hppa-linux-gnu-" v9.3.0
on x86-64 host machine. I got the following warning:
block/genhd.c: In function ‘diskstats_show’:
block/genhd.c:1227:1: warning: the frame size of 1688 bytes is larger
than 1280 bytes [-Wframe-larger-than=]
1227 | }
By Reduced the stack footprint by using the %pg printk specifier instead
of disk_name to remove the need for the on-stack buffer.
Signed-off-by: Abd-Alrhman Masalkhi <abd.masalkhi@gmail.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Link: https://lore.kernel.org/r/20210727062518.122108-2-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
Now that we've stopped using inode references for anything meaninful
in the block layer get rid of the helper to put it and just open code
the call to iput on the block_device inode.
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: Chaitanya Kulkarni <ckulkarnilinux@gmail.com> Link: https://lore.kernel.org/r/20210722075402.983367-10-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
Instead of acquiring an inode reference on open make sure partitions
always hold device model references to the disk while alive, and switch
open to grab only a device model reference to the opened block device.
If that is a partition the disk reference is transitively held by the
partition already.
Unhash the whole device inode early in del_gendisk. This allows to
remove the first GENHD_FL_UP check in the open path as we simply
won't find a just removed inode. The second non-racy check after
taking open_mutex is still kept.
dm-writecache: use bvec_kmap_local instead of bvec_kmap_irq
There is no need to disable interrupts in bio_copy_block, and the local
only mappings helps to avoid any sort of problems with stray writes
into the bio data.
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Link: https://lore.kernel.org/r/20210727055646.118787-8-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
Oliver Hartkopp [Wed, 14 Jul 2021 19:56:55 +0000 (21:56 +0200)]
ioprio: move user space relevant ioprio bits to UAPI includes
systemd added a modified copy of include/linux/ioprio.h into its
code to get the relevant content definitions for the exposed
ioprio_[get|set] system calls.
Move the user space relevant ioprio bits to the UAPI includes to be
able to use the ioprio_[get|set] syscalls as intended.
Linus Torvalds [Sun, 1 Aug 2021 19:25:30 +0000 (12:25 -0700)]
Merge tag 'perf-tools-fixes-for-v5.14-2021-08-01' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux
Pull perf tools fixes from Arnaldo Carvalho de Melo:
- Revert "perf map: Fix dso->nsinfo refcounting", this makes 'perf top'
abort, uncovering a design flaw on how namespace information is kept.
The fix for that is more than we can do right now, leave it for the
next merge window.
- Split --dump-raw-trace by AUX records for ARM's CoreSight, fixing up
the decoding of some records.
- Fix PMU alias matching.
Thanks to James Clark and John Garry for these fixes.
* tag 'perf-tools-fixes-for-v5.14-2021-08-01' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux:
Revert "perf map: Fix dso->nsinfo refcounting"
perf pmu: Fix alias matching
perf cs-etm: Split --dump-raw-trace by AUX records
Linus Torvalds [Sun, 1 Aug 2021 19:18:44 +0000 (12:18 -0700)]
Merge tag 'powerpc-5.14-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc fixes from Michael Ellerman:
- Don't use r30 in VDSO code, to avoid breaking existing Go lang
programs.
- Change an export symbol to allow non-GPL modules to use spinlocks
again.
Thanks to Paul Menzel, and Srikar Dronamraju.
* tag 'powerpc-5.14-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/vdso: Don't use r30 to avoid breaking Go lang
powerpc/pseries: Fix regression while building external modules
Linus Torvalds [Sun, 1 Aug 2021 19:07:23 +0000 (12:07 -0700)]
Merge tag 'xfs-5.14-fixes-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux
Pull xfs fixes from Darrick Wong:
"This contains a bunch of bug fixes in XFS.
Dave and I have been busy the last couple of weeks to find and fix as
many log recovery bugs as we can find; here are the results so far. Go
fstests -g recoveryloop! ;)
- Fix a number of coordination bugs relating to cache flushes for
metadata writeback, cache flushes for multi-buffer log writes, and
FUA writes for single-buffer log writes
- Fix a bug with incorrect replay of attr3 blocks
- Fix unnecessary stalls when flushing logs to disk
- Fix spoofing problems when recovering realtime bitmap blocks"
* tag 'xfs-5.14-fixes-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
xfs: prevent spoofing of rtbitmap blocks when recovering buffers
xfs: limit iclog tail updates
xfs: need to see iclog flags in tracing
xfs: Enforce attr3 buffer recovery order
xfs: logging the on disk inode LSN can make it go backwards
xfs: avoid unnecessary waits in xfs_log_force_lsn()
xfs: log forces imply data device cache flushes
xfs: factor out forced iclog flushes
xfs: fix ordering violation between cache flushes and tail updates
xfs: fold __xlog_state_release_iclog into xlog_state_release_iclog
xfs: external logs need to flush data device
xfs: flush data dev on external log write
Merge tag '5.14-rc3-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6
Pull cifs fixes from Steve French:
"Three cifs/smb3 fixes, including two for stable, and a fix for an
fallocate problem noticed by Clang"
* tag '5.14-rc3-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6:
cifs: add missing parsing of backupuid
smb3: rc uninitialized in one fallocate path
SMB3: fix readpage for large swap cache
- mlx5e: RX, avoid possible data corruption w/ relaxed ordering and
LRO
- phy: re-add check for PHY_BRCM_DIS_TXCRXC_NOENRGY on the BCM54811
PHY
- sctp: fix return value check in __sctp_rcv_asconf_lookup
Previous releases - always broken:
- bpf:
- more spectre corner case fixes, introduce a BPF nospec
instruction for mitigating Spectre v4
- fix OOB read when printing XDP link fdinfo
- sockmap: fix cleanup related races
- mac80211: fix enabling 4-address mode on a sta vif after assoc
- can:
- raw: raw_setsockopt(): fix raw_rcv panic for sock UAF
- j1939: j1939_session_deactivate(): clarify lifetime of session
object, avoid UAF
- fix number of identical memory leaks in USB drivers
- tipc:
- do not blindly write skb_shinfo frags when doing decryption
- fix sleeping in tipc accept routine"
* tag 'net-5.14-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (91 commits)
gve: Update MAINTAINERS list
can: esd_usb2: fix memory leak
can: ems_usb: fix memory leak
can: usb_8dev: fix memory leak
can: mcba_usb_start(): add missing urb->transfer_dma initialization
can: hi311x: fix a signedness bug in hi3110_cmd()
MAINTAINERS: add Yasushi SHOJI as reviewer for the Microchip CAN BUS Analyzer Tool driver
bpf: Fix leakage due to insufficient speculative store bypass mitigation
bpf: Introduce BPF nospec instruction for mitigating Spectre v4
sis900: Fix missing pci_disable_device() in probe and remove
net: let flow have same hash in two directions
nfc: nfcsim: fix use after free during module unload
tulip: windbond-840: Fix missing pci_disable_device() in probe and remove
sctp: fix return value check in __sctp_rcv_asconf_lookup
nfc: s3fwrn5: fix undefined parameter values in dev_err()
net/mlx5: Fix mlx5_vport_tbl_attr chain from u16 to u32
net/mlx5e: Fix nullptr in mlx5e_hairpin_get_mdev()
net/mlx5: Unload device upon firmware fatal error
net/mlx5e: Fix page allocation failure for ptp-RQ over SF
net/mlx5e: Fix page allocation failure for trap-RQ over SF
...