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[ Upstream commit 5fe56de799ad03e92d794c7936bf363922b571df ]
If in blk_mq_dispatch_rq_list() we find no budget, then we break of the
dispatch loop, but the request may keep the driver tag, evaulated
in 'nxt' in the previous loop iteration.
Fix by putting the driver tag for that request.
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
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commit d6c8e949a35d6906d6c03a50e9a9cdf4e494528a upstream.
Systemtap 4.2 is unable to correctly interpret the "u32 (*missed_ppm)[2]"
argument of the iocost_ioc_vrate_adj trace entry defined in
include/trace/events/iocost.h leading to the following error:
/tmp/stapAcz0G0/stap_c89c58b83cea1724e26395efa9ed4939_6321_aux_6.c:78:8:
error: expected ‘;’, ‘,’ or ‘)’ before ‘*’ token
, u32[]* __tracepoint_arg_missed_ppm
That argument type is indeed rather complex and hard to read. Looking
at block/blk-iocost.c. It is just a 2-entry u32 array. By simplifying
the argument to a simple "u32 *missed_ppm" and adjusting the trace
entry accordingly, the compilation error was gone.
Fixes: 7caa47151ab2 ("blkcg: implement blk-iocost")
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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[ Upstream commit cb6b771b05c3026a85ed4817c1b87c5e6f41d136 ]
The previous fix had an off by one in the bd_openers checking, counting
the callers blkdev_get.
Fixes: d3ef5536274f ("block: fix busy device checking in blk_drop_partitions")
Reported-by: Qian Cai <cai@lca.pw>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Qian Cai <cai@lca.pw>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit d3ef5536274faf89e626276b833be122a16bdb81 ]
bd_super is only set by get_tree_bdev and mount_bdev, and thus not by
other openers like btrfs or the XFS realtime and log devices, as well as
block devices directly opened from user space. Check bd_openers
instead.
Fixes: 77032ca66f86 ("Return EBUSY from BLKRRPART for mounted whole-dev fs")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
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commit 4d38a87fbb77fb9ff2ff4e914162a8ae6453eff5 upstream.
In bfq_pd_offline(), the function bfq_flush_idle_tree() is invoked to
flush the rb tree that contains all idle entities belonging to the pd
(cgroup) being destroyed. In particular, bfq_flush_idle_tree() is
invoked before bfq_reparent_active_queues(). Yet the latter may happen
to add some entities to the idle tree. It happens if, in some of the
calls to bfq_bfqq_move() performed by bfq_reparent_active_queues(),
the queue to move is empty and gets expired.
This commit simply reverses the invocation order between
bfq_flush_idle_tree() and bfq_reparent_active_queues().
Tested-by: cki-project@redhat.com
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit 576682fa52cbd95deb3773449566274f206acc58 upstream.
bfq_reparent_leaf_entity() reparents the input leaf entity (a leaf
entity represents just a bfq_queue in an entity tree). Yet, the input
entity is guaranteed to always be a leaf entity only in two-level
entity trees. In this respect, because of the error fixed by
commit 14afc5936197 ("block, bfq: fix overwrite of bfq_group pointer
in bfq_find_set_group()"), all (wrongly collapsed) entity trees happened
to actually have only two levels. After the latter commit, this does not
hold any longer.
This commit fixes this problem by modifying
bfq_reparent_leaf_entity(), so that it searches an active leaf entity
down the path that stems from the input entity. Such a leaf entity is
guaranteed to exist when bfq_reparent_leaf_entity() is invoked.
Tested-by: cki-project@redhat.com
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit c8997736650060594845e42c5d01d3118aec8d25 upstream.
A bfq_put_queue() may be invoked in __bfq_bic_change_cgroup(). The
goal of this put is to release a process reference to a bfq_queue. But
process-reference releases may trigger also some extra operation, and,
to this goal, are handled through bfq_release_process_ref(). So, turn
the invocation of bfq_put_queue() into an invocation of
bfq_release_process_ref().
Tested-by: cki-project@redhat.com
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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[ Upstream commit 2f95fa5c955d0a9987ffdc3a095e2f4e62c5f2a9 ]
In bfq_idle_slice_timer func, bfqq = bfqd->in_service_queue is
not in bfqd-lock critical section. The bfqq, which is not
equal to NULL in bfq_idle_slice_timer, may be freed after passing
to bfq_idle_slice_timer_body. So we will access the freed memory.
In addition, considering the bfqq may be in race, we should
firstly check whether bfqq is in service before doing something
on it in bfq_idle_slice_timer_body func. If the bfqq in race is
not in service, it means the bfqq has been expired through
__bfq_bfqq_expire func, and wait_request flags has been cleared in
__bfq_bfqd_reset_in_service func. So we do not need to re-clear the
wait_request of bfqq which is not in service.
KASAN log is given as follows:
[13058.354613] ==================================================================
[13058.354640] BUG: KASAN: use-after-free in bfq_idle_slice_timer+0xac/0x290
[13058.354644] Read of size 8 at addr ffffa02cf3e63f78 by task fork13/19767
[13058.354646]
[13058.354655] CPU: 96 PID: 19767 Comm: fork13
[13058.354661] Call trace:
[13058.354667] dump_backtrace+0x0/0x310
[13058.354672] show_stack+0x28/0x38
[13058.354681] dump_stack+0xd8/0x108
[13058.354687] print_address_description+0x68/0x2d0
[13058.354690] kasan_report+0x124/0x2e0
[13058.354697] __asan_load8+0x88/0xb0
[13058.354702] bfq_idle_slice_timer+0xac/0x290
[13058.354707] __hrtimer_run_queues+0x298/0x8b8
[13058.354710] hrtimer_interrupt+0x1b8/0x678
[13058.354716] arch_timer_handler_phys+0x4c/0x78
[13058.354722] handle_percpu_devid_irq+0xf0/0x558
[13058.354731] generic_handle_irq+0x50/0x70
[13058.354735] __handle_domain_irq+0x94/0x110
[13058.354739] gic_handle_irq+0x8c/0x1b0
[13058.354742] el1_irq+0xb8/0x140
[13058.354748] do_wp_page+0x260/0xe28
[13058.354752] __handle_mm_fault+0x8ec/0x9b0
[13058.354756] handle_mm_fault+0x280/0x460
[13058.354762] do_page_fault+0x3ec/0x890
[13058.354765] do_mem_abort+0xc0/0x1b0
[13058.354768] el0_da+0x24/0x28
[13058.354770]
[13058.354773] Allocated by task 19731:
[13058.354780] kasan_kmalloc+0xe0/0x190
[13058.354784] kasan_slab_alloc+0x14/0x20
[13058.354788] kmem_cache_alloc_node+0x130/0x440
[13058.354793] bfq_get_queue+0x138/0x858
[13058.354797] bfq_get_bfqq_handle_split+0xd4/0x328
[13058.354801] bfq_init_rq+0x1f4/0x1180
[13058.354806] bfq_insert_requests+0x264/0x1c98
[13058.354811] blk_mq_sched_insert_requests+0x1c4/0x488
[13058.354818] blk_mq_flush_plug_list+0x2d4/0x6e0
[13058.354826] blk_flush_plug_list+0x230/0x548
[13058.354830] blk_finish_plug+0x60/0x80
[13058.354838] read_pages+0xec/0x2c0
[13058.354842] __do_page_cache_readahead+0x374/0x438
[13058.354846] ondemand_readahead+0x24c/0x6b0
[13058.354851] page_cache_sync_readahead+0x17c/0x2f8
[13058.354858] generic_file_buffered_read+0x588/0xc58
[13058.354862] generic_file_read_iter+0x1b4/0x278
[13058.354965] ext4_file_read_iter+0xa8/0x1d8 [ext4]
[13058.354972] __vfs_read+0x238/0x320
[13058.354976] vfs_read+0xbc/0x1c0
[13058.354980] ksys_read+0xdc/0x1b8
[13058.354984] __arm64_sys_read+0x50/0x60
[13058.354990] el0_svc_common+0xb4/0x1d8
[13058.354994] el0_svc_handler+0x50/0xa8
[13058.354998] el0_svc+0x8/0xc
[13058.354999]
[13058.355001] Freed by task 19731:
[13058.355007] __kasan_slab_free+0x120/0x228
[13058.355010] kasan_slab_free+0x10/0x18
[13058.355014] kmem_cache_free+0x288/0x3f0
[13058.355018] bfq_put_queue+0x134/0x208
[13058.355022] bfq_exit_icq_bfqq+0x164/0x348
[13058.355026] bfq_exit_icq+0x28/0x40
[13058.355030] ioc_exit_icq+0xa0/0x150
[13058.355035] put_io_context_active+0x250/0x438
[13058.355038] exit_io_context+0xd0/0x138
[13058.355045] do_exit+0x734/0xc58
[13058.355050] do_group_exit+0x78/0x220
[13058.355054] __wake_up_parent+0x0/0x50
[13058.355058] el0_svc_common+0xb4/0x1d8
[13058.355062] el0_svc_handler+0x50/0xa8
[13058.355066] el0_svc+0x8/0xc
[13058.355067]
[13058.355071] The buggy address belongs to the object at ffffa02cf3e63e70#012 which belongs to the cache bfq_queue of size 464
[13058.355075] The buggy address is located 264 bytes inside of#012 464-byte region [ffffa02cf3e63e70, ffffa02cf3e64040)
[13058.355077] The buggy address belongs to the page:
[13058.355083] page:ffff7e80b3cf9800 count:1 mapcount:0 mapping:ffff802db5c90780 index:0xffffa02cf3e606f0 compound_mapcount: 0
[13058.366175] flags: 0x2ffffe0000008100(slab|head)
[13058.370781] raw: 2ffffe0000008100 ffff7e80b53b1408 ffffa02d730c1c90 ffff802db5c90780
[13058.370787] raw: ffffa02cf3e606f0 0000000000370023 00000001ffffffff 0000000000000000
[13058.370789] page dumped because: kasan: bad access detected
[13058.370791]
[13058.370792] Memory state around the buggy address:
[13058.370797] ffffa02cf3e63e00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fb fb
[13058.370801] ffffa02cf3e63e80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[13058.370805] >ffffa02cf3e63f00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[13058.370808] ^
[13058.370811] ffffa02cf3e63f80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[13058.370815] ffffa02cf3e64000: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
[13058.370817] ==================================================================
[13058.370820] Disabling lock debugging due to kernel taint
Here, we directly pass the bfqd to bfq_idle_slice_timer_body func.
--
V2->V3: rewrite the comment as suggested by Paolo Valente
V1->V2: add one comment, and add Fixes and Reported-by tag.
Fixes: aee69d78d ("block, bfq: introduce the BFQ-v0 I/O scheduler as an extra scheduler")
Acked-by: Paolo Valente <paolo.valente@linaro.org>
Reported-by: Wang Wang <wangwang2@huawei.com>
Signed-off-by: Zhiqiang Liu <liuzhiqiang26@huawei.com>
Signed-off-by: Feilong Lin <linfeilong@huawei.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit 11bde986002c0af67eb92d73321d06baefae7128 ]
Check for overflow in addition before checking for end-of-block-device.
Steps to reproduce:
#define _GNU_SOURCE 1
#include <sys/ioctl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
typedef unsigned long long __u64;
struct blk_zone_range {
__u64 sector;
__u64 nr_sectors;
};
#define BLKRESETZONE _IOW(0x12, 131, struct blk_zone_range)
int main(void)
{
int fd = open("/dev/nullb0", O_RDWR|O_DIRECT);
struct blk_zone_range zr = {4096, 0xfffffffffffff000ULL};
ioctl(fd, BLKRESETZONE, &zr);
return 0;
}
BUG: KASAN: null-ptr-deref in submit_bio_wait+0x74/0xe0
Write of size 8 at addr 0000000000000040 by task a.out/1590
CPU: 8 PID: 1590 Comm: a.out Not tainted 5.6.0-rc1-00019-g359c92c02bfa #2
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20190711_202441-buildvm-armv7-10.arm.fedoraproject.org-2.fc31 04/01/2014
Call Trace:
dump_stack+0x76/0xa0
__kasan_report.cold+0x5/0x3e
kasan_report+0xe/0x20
submit_bio_wait+0x74/0xe0
blkdev_zone_mgmt+0x26f/0x2a0
blkdev_zone_mgmt_ioctl+0x14b/0x1b0
blkdev_ioctl+0xb28/0xe60
block_ioctl+0x69/0x80
ksys_ioctl+0x3af/0xa50
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alexey Dobriyan (SK hynix) <adobriyan@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit 30a2da7b7e225ef6c87a660419ea04d3cef3f6a7 ]
There is a potential race between ioc_release_fn() and
ioc_clear_queue() as shown below, due to which below kernel
crash is observed. It also can result into use-after-free
issue.
context#1: context#2:
ioc_release_fn() __ioc_clear_queue() gets the same icq
->spin_lock(&ioc->lock); ->spin_lock(&ioc->lock);
->ioc_destroy_icq(icq);
->list_del_init(&icq->q_node);
->call_rcu(&icq->__rcu_head,
icq_free_icq_rcu);
->spin_unlock(&ioc->lock);
->ioc_destroy_icq(icq);
->hlist_del_init(&icq->ioc_node);
This results into below crash as this memory
is now used by icq->__rcu_head in context#1.
There is a chance that icq could be free'd
as well.
22150.386550: <6> Unable to handle kernel write to read-only memory
at virtual address ffffffaa8d31ca50
...
Call trace:
22150.607350: <2> ioc_destroy_icq+0x44/0x110
22150.611202: <2> ioc_clear_queue+0xac/0x148
22150.615056: <2> blk_cleanup_queue+0x11c/0x1a0
22150.619174: <2> __scsi_remove_device+0xdc/0x128
22150.623465: <2> scsi_forget_host+0x2c/0x78
22150.627315: <2> scsi_remove_host+0x7c/0x2a0
22150.631257: <2> usb_stor_disconnect+0x74/0xc8
22150.635371: <2> usb_unbind_interface+0xc8/0x278
22150.639665: <2> device_release_driver_internal+0x198/0x250
22150.644897: <2> device_release_driver+0x24/0x30
22150.649176: <2> bus_remove_device+0xec/0x140
22150.653204: <2> device_del+0x270/0x460
22150.656712: <2> usb_disable_device+0x120/0x390
22150.660918: <2> usb_disconnect+0xf4/0x2e0
22150.664684: <2> hub_event+0xd70/0x17e8
22150.668197: <2> process_one_work+0x210/0x480
22150.672222: <2> worker_thread+0x32c/0x4c8
Fix this by adding a new ICQ_DESTROYED flag in ioc_destroy_icq() to
indicate this icq is once marked as destroyed. Also, ensure
__ioc_clear_queue() is accessing icq within rcu_read_lock/unlock so
that icq doesn't get free'd up while it is still using it.
Signed-off-by: Sahitya Tummala <stummala@codeaurora.org>
Co-developed-by: Pradeep P V K <ppvk@codeaurora.org>
Signed-off-by: Pradeep P V K <ppvk@codeaurora.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit fd1bb3ae54a9a2e0c42709de861c69aa146b8955 ]
Commit ecedd3d7e199 ("block, bfq: get extra ref to prevent a queue
from being freed during a group move") gets an extra reference to a
bfq_queue before possibly deactivating it (temporarily), in
bfq_bfqq_move(). This prevents the bfq_queue from disappearing before
being reactivated in its new group.
Yet, the bfq_queue may also be expired (i.e., its service may be
stopped) before the bfq_queue is deactivated. And also an expiration
may lead to a premature freeing. This commit fixes this issue by
simply moving forward the getting of the extra reference already
introduced by commit ecedd3d7e199 ("block, bfq: get extra ref to
prevent a queue from being freed during a group move").
Reported-by: cki-project@redhat.com
Tested-by: cki-project@redhat.com
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit e74d93e96d721c4297f2a900ad0191890d2fc2b0 ]
Field bdi->io_pages added in commit 9491ae4aade6 ("mm: don't cap request
size based on read-ahead setting") removes unneeded split of read requests.
Stacked drivers do not call blk_queue_max_hw_sectors(). Instead they set
limits of their devices by blk_set_stacking_limits() + disk_stack_limits().
Field bio->io_pages stays zero until user set max_sectors_kb via sysfs.
This patch updates io_pages after merging limits in disk_stack_limits().
Commit c6d6e9b0f6b4 ("dm: do not allow readahead to limit IO size") fixed
the same problem for device-mapper devices, this one fixes MD RAIDs.
Fixes: 9491ae4aade6 ("mm: don't cap request size based on read-ahead setting")
Reviewed-by: Paul Menzel <pmenzel@molgen.mpg.de>
Reviewed-by: Bob Liu <bob.liu@oracle.com>
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit d0930bb8f46b8fb4a7d429c0bf1c91b3ed00a7cf ]
q->nr_hw_queues must only be updated once it is known that
blk_mq_realloc_hw_ctxs() has succeeded. Otherwise it can happen that
reallocation fails and that q->nr_hw_queues is larger than the number of
allocated hardware queues. This patch fixes the following crash if
increasing the number of hardware queues fails:
BUG: KASAN: null-ptr-deref in blk_mq_map_swqueue+0x775/0x810
Write of size 8 at addr 0000000000000118 by task check/977
CPU: 3 PID: 977 Comm: check Not tainted 5.6.0-rc1-dbg+ #8
Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
Call Trace:
dump_stack+0xa5/0xe6
__kasan_report.cold+0x65/0x99
kasan_report+0x16/0x20
check_memory_region+0x140/0x1b0
memset+0x28/0x40
blk_mq_map_swqueue+0x775/0x810
blk_mq_update_nr_hw_queues+0x468/0x710
nullb_device_submit_queues_store+0xf7/0x1a0 [null_blk]
configfs_write_file+0x1c4/0x250 [configfs]
__vfs_write+0x4c/0x90
vfs_write+0x145/0x2c0
ksys_write+0xd7/0x180
__x64_sys_write+0x47/0x50
do_syscall_64+0x6f/0x2f0
entry_SYSCALL_64_after_hwframe+0x49/0xbe
Fixes: ac0d6b926e74 ("block: Reduce the amount of memory required per request queue")
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Cc: Keith Busch <kbusch@kernel.org>
Cc: Johannes Thumshirn <jth@kernel.org>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
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commit 6e66b49392419f3fe134e1be583323ef75da1e4b upstream.
blk_mq_map_queues() and multiple .map_queues() implementations expect that
set->map[HCTX_TYPE_DEFAULT].nr_queues is set to the number of hardware
queues. Hence set .nr_queues before calling these functions. This patch
fixes the following kernel warning:
WARNING: CPU: 0 PID: 2501 at include/linux/cpumask.h:137
Call Trace:
blk_mq_run_hw_queue+0x19d/0x350 block/blk-mq.c:1508
blk_mq_run_hw_queues+0x112/0x1a0 block/blk-mq.c:1525
blk_mq_requeue_work+0x502/0x780 block/blk-mq.c:775
process_one_work+0x9af/0x1740 kernel/workqueue.c:2269
worker_thread+0x98/0xe40 kernel/workqueue.c:2415
kthread+0x361/0x430 kernel/kthread.c:255
Fixes: ed76e329d74a ("blk-mq: abstract out queue map") # v5.0
Reported-by: syzbot+d44e1b26ce5c3e77458d@syzkaller.appspotmail.com
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Cc: Johannes Thumshirn <jth@kernel.org>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Commit b72053072c0b ("block: allow partitions on host aware zone
devices") introduced the helper function disk_has_partitions() to check
if a given disk has valid partitions. However, since this function result
directly depends on the disk partition table length rather than the
actual existence of valid partitions in the table, it returns true even
after all partitions are removed from the disk. For host aware zoned
block devices, this results in zone management support to be kept
disabled even after removing all partitions.
Fix this by changing disk_has_partitions() to walk through the partition
table entries and return true if and only if a valid non-zero size
partition is found.
Fixes: b72053072c0b ("block: allow partitions on host aware zone devices")
Cc: stable@vger.kernel.org # 5.5
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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commit 01e99aeca397 ("blk-mq: insert passthrough request into
hctx->dispatch directly") may change to add flush request to the tail
of dispatch by applying the 'add_head' parameter of
blk_mq_sched_insert_request.
Turns out this way causes performance regression on NCQ controller because
flush is non-NCQ command, which can't be queued when there is any in-flight
NCQ command. When adding flush rq to the front of hctx->dispatch, it is
easier to introduce extra time to flush rq's latency compared with adding
to the tail of dispatch queue because of S_SCHED_RESTART, then chance of
flush merge is increased, and less flush requests may be issued to
controller.
So always insert flush request to the front of dispatch queue just like
before applying commit 01e99aeca397 ("blk-mq: insert passthrough request
into hctx->dispatch directly").
Cc: Damien Le Moal <Damien.LeMoal@wdc.com>
Cc: Shinichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Reported-by: Shinichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Fixes: 01e99aeca397 ("blk-mq: insert passthrough request into hctx->dispatch directly")
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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vtimes may wrap and time_before/after64() should be used to determine
whether a given vtime is before or after another. iocg_is_idle() was
incorrectly using plain "<" comparison do determine whether done_vtime
is before vtime. Here, the only thing we're interested in is whether
done_vtime matches vtime which indicates that there's nothing in
flight. Let's test for inequality instead.
Signed-off-by: Tejun Heo <tj@kernel.org>
Fixes: 7caa47151ab2 ("blkcg: implement blk-iocost")
Cc: stable@vger.kernel.org # v5.4+
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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The bfq_find_set_group() function takes as input a blkcg (which represents
a cgroup) and retrieves the corresponding bfq_group, then it updates the
bfq internal group hierarchy (see comments inside the function for why
this is needed) and finally it returns the bfq_group.
In the hierarchy update cycle, the pointer holding the correct bfq_group
that has to be returned is mistakenly used to traverse the hierarchy
bottom to top, meaning that in each iteration it gets overwritten with the
parent of the current group. Since the update cycle stops at root's
children (depth = 2), the overwrite becomes a problem only if the blkcg
describes a cgroup at a hierarchy level deeper than that (depth > 2). In
this case the root's child that happens to be also an ancestor of the
correct bfq_group is returned. The main consequence is that processes
contained in a cgroup at depth greater than 2 are wrongly placed in the
group described above by BFQ.
This commits fixes this problem by using a different bfq_group pointer in
the update cycle in order to avoid the overwrite of the variable holding
the original group reference.
Reported-by: Kwon Je Oh <kwonje.oh2@gmail.com>
Signed-off-by: Carlo Nonato <carlo.nonato95@gmail.com>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Commit ee63cfa7fc19 ("block: add kblockd_schedule_work_on()")
introduced the helper in 2016. Remove it because since then no caller
was added.
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Daniel Wagner <dwagner@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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The struct blk_mq_hw_ctx pointer argument in blk_mq_put_tag(),
blk_mq_poll_nsecs(), and blk_mq_poll_hybrid_sleep() is unused, so remove
it.
Overall obj code size shows a minor reduction, before:
text data bss dec hex filename
27306 1312 0 28618 6fca block/blk-mq.o
4303 272 0 4575 11df block/blk-mq-tag.o
after:
27282 1312 0 28594 6fb2 block/blk-mq.o
4311 272 0 4583 11e7 block/blk-mq-tag.o
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: John Garry <john.garry@huawei.com>
--
This minor patch had been carried as part of the blk-mq shared tags RFC,
I'd rather not carry it anymore as it required rebasing, so now or never..
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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For some reason, device may be in one situation which can't handle
FS request, so STS_RESOURCE is always returned and the FS request
will be added to hctx->dispatch. However passthrough request may
be required at that time for fixing the problem. If passthrough
request is added to scheduler queue, there isn't any chance for
blk-mq to dispatch it given we prioritize requests in hctx->dispatch.
Then the FS IO request may never be completed, and IO hang is caused.
So passthrough request has to be added to hctx->dispatch directly
for fixing the IO hang.
Fix this issue by inserting passthrough request into hctx->dispatch
directly together withing adding FS request to the tail of
hctx->dispatch in blk_mq_dispatch_rq_list(). Actually we add FS request
to tail of hctx->dispatch at default, see blk_mq_request_bypass_insert().
Then it becomes consistent with original legacy IO request
path, in which passthrough request is always added to q->queue_head.
Cc: Dongli Zhang <dongli.zhang@oracle.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Ewan D. Milne <emilne@redhat.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Pull more block updates from Jens Axboe:
"Some later arrivals, but all fixes at this point:
- bcache fix series (Coly)
- Series of BFQ fixes (Paolo)
- NVMe pull request from Keith with a few minor NVMe fixes
- Various little tweaks"
* tag 'block-5.6-2020-02-05' of git://git.kernel.dk/linux-block: (23 commits)
nvmet: update AEN list and array at one place
nvmet: Fix controller use after free
nvmet: Fix error print message at nvmet_install_queue function
brd: check and limit max_part par
nvme-pci: remove nvmeq->tags
nvmet: fix dsm failure when payload does not match sgl descriptor
nvmet: Pass lockdep expression to RCU lists
block, bfq: clarify the goal of bfq_split_bfqq()
block, bfq: get a ref to a group when adding it to a service tree
block, bfq: remove ifdefs from around gets/puts of bfq groups
block, bfq: extend incomplete name of field on_st
block, bfq: get extra ref to prevent a queue from being freed during a group move
block, bfq: do not insert oom queue into position tree
block, bfq: do not plug I/O for bfq_queues with no proc refs
bcache: check return value of prio_read()
bcache: fix incorrect data type usage in btree_flush_write()
bcache: add readahead cache policy options via sysfs interface
bcache: explicity type cast in bset_bkey_last()
bcache: fix memory corruption in bch_cache_accounting_clear()
xen/blkfront: limit allocated memory size to actual use case
...
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The exact, general goal of the function bfq_split_bfqq() is not that
apparent. Add a comment to make it clear.
Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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BFQ schedules generic entities, which may represent either bfq_queues
or groups of bfq_queues. When an entity is inserted into a service
tree, a reference must be taken, to make sure that the entity does not
disappear while still referred in the tree. Unfortunately, such a
reference is mistakenly taken only if the entity represents a
bfq_queue. This commit takes a reference also in case the entity
represents a group.
Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Tested-by: Chris Evich <cevich@redhat.com>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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ifdefs around gets and puts of bfq groups reduce readability, remove them.
Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Reported-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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The flag on_st in the bfq_entity data structure is true if the entity
is on a service tree or is in service. Yet the name of the field,
confusingly, does not mention the second, very important case. Extend
the name to mention the second case too.
Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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move
In bfq_bfqq_move(), the bfq_queue, say Q, to be moved to a new group
may happen to be deactivated in the scheduling data structures of the
source group (and then activated in the destination group). If Q is
referred only by the data structures in the source group when the
deactivation happens, then Q is freed upon the deactivation.
This commit addresses this issue by getting an extra reference before
the possible deactivation, and releasing this extra reference after Q
has been moved.
Tested-by: Chris Evich <cevich@redhat.com>
Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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BFQ maintains an ordered list, implemented with an RB tree, of
head-request positions of non-empty bfq_queues. This position tree,
inherited from CFQ, is used to find bfq_queues that contain I/O close
to each other. BFQ merges these bfq_queues into a single shared queue,
if this boosts throughput on the device at hand.
There is however a special-purpose bfq_queue that does not participate
in queue merging, the oom bfq_queue. Yet, also this bfq_queue could be
wrongly added to the position tree. So bfqq_find_close() could return
the oom bfq_queue, which is a source of further troubles in an
out-of-memory situation. This commit prevents the oom bfq_queue from
being inserted into the position tree.
Tested-by: Patrick Dung <patdung100@gmail.com>
Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Commit 478de3380c1c ("block, bfq: deschedule empty bfq_queues not
referred by any process") fixed commit 3726112ec731 ("block, bfq:
re-schedule empty queues if they deserve I/O plugging") by
descheduling an empty bfq_queue when it remains with not process
reference. Yet, this still left a case uncovered: an empty bfq_queue
with not process reference that remains in service. This happens for
an in-service sync bfq_queue that is deemed to deserve I/O-dispatch
plugging when it remains empty. Yet no new requests will arrive for
such a bfq_queue if no process sends requests to it any longer. Even
worse, the bfq_queue may happen to be prematurely freed while still in
service (because there may remain no reference to it any longer).
This commit solves this problem by preventing I/O dispatch from being
plugged for the in-service bfq_queue, if the latter has no process
reference (the bfq_queue is then prevented from remaining in service).
Fixes: 3726112ec731 ("block, bfq: re-schedule empty queues if they deserve I/O plugging")
Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Reported-by: Patrick Dung <patdung100@gmail.com>
Tested-by: Patrick Dung <patdung100@gmail.com>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Pull SCSI updates from James Bottomley:
"This series is slightly unusual because it includes Arnd's compat
ioctl tree here:
1c46a2cf2dbd Merge tag 'block-ioctl-cleanup-5.6' into 5.6/scsi-queue
Excluding Arnd's changes, this is mostly an update of the usual
drivers: megaraid_sas, mpt3sas, qla2xxx, ufs, lpfc, hisi_sas.
There are a couple of core and base updates around error propagation
and atomicity in the attribute container base we use for the SCSI
transport classes.
The rest is minor changes and updates"
* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (149 commits)
scsi: hisi_sas: Rename hisi_sas_cq.pci_irq_mask
scsi: hisi_sas: Add prints for v3 hw interrupt converge and automatic affinity
scsi: hisi_sas: Modify the file permissions of trigger_dump to write only
scsi: hisi_sas: Replace magic number when handle channel interrupt
scsi: hisi_sas: replace spin_lock_irqsave/spin_unlock_restore with spin_lock/spin_unlock
scsi: hisi_sas: use threaded irq to process CQ interrupts
scsi: ufs: Use UFS device indicated maximum LU number
scsi: ufs: Add max_lu_supported in struct ufs_dev_info
scsi: ufs: Delete is_init_prefetch from struct ufs_hba
scsi: ufs: Inline two functions into their callers
scsi: ufs: Move ufshcd_get_max_pwr_mode() to ufshcd_device_params_init()
scsi: ufs: Split ufshcd_probe_hba() based on its called flow
scsi: ufs: Delete struct ufs_dev_desc
scsi: ufs: Fix ufshcd_probe_hba() reture value in case ufshcd_scsi_add_wlus() fails
scsi: ufs-mediatek: enable low-power mode for hibern8 state
scsi: ufs: export some functions for vendor usage
scsi: ufs-mediatek: add dbg_register_dump implementation
scsi: qla2xxx: Fix a NULL pointer dereference in an error path
scsi: qla1280: Make checking for 64bit support consistent
scsi: megaraid_sas: Update driver version to 07.713.01.00-rc1
...
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Pull core block updates from Jens Axboe:
"This may be the most quiet round we've had in years. I'm not
complaining. Really not a lot to detail here, outside of spelling and
documentation improvements/fixes, we have:
- Allow t10-pi to be modular (Herbert)
- Remove dead code in bfq (Alex)
- Mark zone management requests with REQ_SYNC (Chaitanya)
- BFQ division improvement (Wen)
- Small series improving plugging (Pavel)"
* tag 'for-5.6/block-2020-01-27' of git://git.kernel.dk/linux-block:
partitions/ldm: fix spelling mistake "to" -> "too"
block, bfq: improve arithmetic division in bfq_delta()
block/bfq: remove unused bfq_class_rt which never used
block: mark zone-mgmt bios with REQ_SYNC
blk-mq: Document functions for sending request
block: Allow t10-pi to be modular
blk-mq: optimise blk_mq_flush_plug_list()
list: introduce list_for_each_continue()
blk-mq: optimise rq sort function
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Host-aware SMR drives can be used with the commands to explicitly manage
zone state, but they can also be used as normal disks. In the former
case it makes perfect sense to allow partitions on them, in the latter
it does not, just like for host managed devices. Add a check to
add_partition to allow partitions on host aware devices, but give
up any zone management capabilities in that case, which also catches
the previously missed case of adding a partition vs just scanning it.
Because sd can rescan the attribute at runtime it needs to check if
a disk has partitions, for which a new helper is added to genhd.h.
Fixes: 5eac3eb30c9a ("block: Remove partition support for zoned block devices")
Reported-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Damien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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There is a spelling mistake in a ldm_error message. Fix it.
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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do_div() does a 64-by-32 division. Use div64_ul() instead of it
if the divisor is unsigned long, to avoid truncation to 32-bit.
And as a nice side effect also cleans up the function a bit.
Signed-off-by: Wen Yang <wenyang@linux.alibaba.com>
Cc: Paolo Valente <paolo.valente@linaro.org>
Cc: Jens Axboe <axboe@fb.com>
Cc: linux-block@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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This macro is never used after introduced from commit aee69d78dec0
("block, bfq: introduce the BFQ-v0 I/O scheduler as an extra scheduler")
Better to remove it.
Signed-off-by: Alex Shi <alex.shi@linux.alibaba.com>
Cc: Paolo Valente <paolo.valente@linaro.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: linux-block@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Logical block size has type unsigned short. That means that it can be at
most 32768. However, there are architectures that can run with 64k pages
(for example arm64) and on these architectures, it may be possible to
create block devices with 64k block size.
For exmaple (run this on an architecture with 64k pages):
Mount will fail with this error because it tries to read the superblock using 2-sector
access:
device-mapper: writecache: I/O is not aligned, sector 2, size 1024, block size 65536
EXT4-fs (dm-0): unable to read superblock
This patch changes the logical block size from unsigned short to unsigned
int to avoid the overflow.
Cc: stable@vger.kernel.org
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Commit 429120f3df2d starts to take account of segment's start dma address
when computing max segment size, and data type of 'unsigned long'
is used to do that. However, the segment mask may be 0xffffffff, so
the figured out segment size may be overflowed in case of zero physical
address on 32bit arch.
Fix the issue by returning queue_max_segment_size() directly when that
happens.
Fixes: 429120f3df2d ("block: fix splitting segments on boundary masks")
Reported-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Cc: Christoph Hellwig <hch@lst.de>
Tested-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Commit 85a8ce62c2ea ("block: add bio_truncate to fix guard_bio_eod")
adds bio_truncate() for handling bio EOD. However, bio_truncate()
doesn't use the passed 'op' parameter from guard_bio_eod's callers.
So bio_trunacate() may retrieve wrong 'op', and zering pages may
not be done for READ bio.
Fixes this issue by moving guard_bio_eod() after bio_set_op_attrs()
in submit_bh_wbc() so that bio_truncate() can always retrieve correct
op info.
Meantime remove the 'op' parameter from guard_bio_eod() because it isn't
used any more.
Cc: Carlos Maiolino <cmaiolino@redhat.com>
Cc: linux-fsdevel@vger.kernel.org
Fixes: 85a8ce62c2ea ("block: add bio_truncate to fix guard_bio_eod")
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Fold in kerneldoc and bio_op() change.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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In the current implementation, final zone-mgmt request is issued with
submit_bio_wait() which marks the bio REQ_SYNC. This is needed since
immediate action is expected for zone-mgmt requests as these are
blocking operations. This also bypasses the scheduler in the
blk_mq_make_request() and dispatches the request directly into the
hw ctx.
This patch marks all the chained bios REQ_SYNC so that we can have
above-mentioned behavior for non-final bios also.
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: Bob Liu <bob.liu@oracle.com>
Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Add or improve documentation for function regarding creating and sending
IO requests to the hardware.
Signed-off-by: André Almeida <andrealmeid@collabora.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Currently t10-pi can only be built into the block layer which via
crc-t10dif pulls in a whole chunk of the Crypto API. In fact all
users of t10-pi work as modules and there is no reason for it to
always be built-in.
This patch adds a new hidden option for t10-pi that is selected
automatically based on BLK_DEV_INTEGRITY and whether the users
of t10-pi are built-in or not.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Having separate implementations of blkdev_ioctl() often leads to these
getting out of sync, despite the comment at the top.
Since most of the ioctl commands are compatible, and we try very hard
not to add any new incompatible ones, move all the common bits into a
shared function and leave only the ones that are historically different
in separate functions for native/compat mode.
To deal with the compat_ptr() conversion, pass both the integer
argument and the pointer argument into the new blkdev_common_ioctl()
and make sure to always use the correct one of these.
blkdev_ioctl() is now only kept as a separate exported interfact
for drivers/char/raw.c, which lacks a compat_ioctl variant.
We should probably either move raw.c to staging if there are no
more users, or export blkdev_compat_ioctl() as well.
Reviewed-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
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There is no need to go through a compat_alloc_user_space()
copy any more, just wrap the function in a small helper that
works the same way for native and compat mode.
Reviewed-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
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Having both in the same file allows a number of simplifications
to the compat path, and makes it more likely that changes to
the native path get applied to the compat version as well.
Reviewed-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
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Most of the HDIO ioctls are only used by the obsolete drivers/ide
subsystem, these can be handled by changing ide_cmd_ioctl() to be aware
of compat mode and doing the correct transformations in place and using
it as both native and compat handlers for all drivers.
The SCSI drivers implementing the same commands are already doing
this in the drivers, so the compat_blkdev_driver_ioctl() function
is no longer needed now.
The BLKSECTSET and HDIO_GETGEO_BIG ioctls are not implemented
in any driver any more and no longer need any conversion.
Reviewed-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
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There is no need for the special cases for the cdrom ioctls any more now,
so make sure that each cdrom driver has a .compat_ioctl() callback and
calls cdrom_compat_ioctl() directly there.
Reviewed-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
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bsg_ioctl() calls into scsi_cmd_ioctl() for a couple of generic commands
and relies on fs/compat_ioctl.c to handle it correctly in compat mode.
Adding a private compat_ioctl() handler avoids that round-trip and lets
us get rid of the generic emulation once this is done.
Note that bsg implements an SG_IO command that is different from the
other drivers and does not need emulation.
Reviewed-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
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Again, there is only one file that needs this, so move the conversion
handler into the native implementation.
Reviewed-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
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There is only one implementation of this ioctl, so move the handling out
of the common block layer code into the place where it's actually needed.
It also gets called indirectly through pktcdvd, which needs to be aware
of this change.
As I noticed, the old implementation of the compat handler failed to
convert the structure on the way out, so the updated fields never got
written back to user space. This is either not important, or it has
never worked and should be fixed now.
Reviewed-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
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A lot of block drivers need only a trivial .compat_ioctl callback.
Add a helper function that can be set as the callback pointer
to only convert the argument using the compat_ptr() conversion
and otherwise assume all input and output data is compatible,
or handled using in_compat_syscall() checks.
This mirrors the compat_ptr_ioctl() helper function used in
character devices.
Reviewed-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
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John Garry
Waiman Long
Christoph Hellwig
Paolo Valente
Zhiqiang Liu
Alexey Dobriyan
Sahitya Tummala
Konstantin Khlebnikov
Bart Van Assche
Shin'ichiro Kawasaki
Ming Lei
Tejun Heo
Carlo Nonato
Daniel Wagner
Linus Torvalds
Colin Ian King
Wen Yang
Alex Shi
Mikulas Patocka
Chaitanya Kulkarni
André Almeida
Herbert Xu
Arnd Bergmann