License cleanup: add SPDX GPL-2.0 license identifier to files with no license
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.
By default all files without license information are under the default
license of the kernel, which is GPL version 2.
Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.
This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.
How this work was done:
Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,
Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.
The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.
The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.
Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).
All documentation files were explicitly excluded.
The following heuristics were used to determine which SPDX license
identifiers to apply.
- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.
For non */uapi/* files that summary was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139
and resulted in the first patch in this series.
If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930
and resulted in the second patch in this series.
- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:
SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1
and that resulted in the third patch in this series.
- when the two scanners agreed on the detected license(s), that became
the concluded license(s).
- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.
- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).
- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.
- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.
In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.
Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.
Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.
In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.
Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct
This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.
These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-01 22:07:57 +08:00
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/* SPDX-License-Identifier: GPL-2.0 */
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2005-04-17 06:20:36 +08:00
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#ifndef _LINUX_GENHD_H
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#define _LINUX_GENHD_H
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/*
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* genhd.h Copyright (C) 1992 Drew Eckhardt
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* Generic hard disk header file by
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* Drew Eckhardt
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*
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* <drew@colorado.edu>
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*/
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#include <linux/types.h>
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2007-05-22 04:08:01 +08:00
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#include <linux/kdev_t.h>
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2016-05-21 08:01:24 +08:00
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#include <linux/uuid.h>
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2018-07-18 19:47:38 +08:00
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#include <linux/blk_types.h>
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2021-09-20 20:33:25 +08:00
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#include <linux/device.h>
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#include <linux/xarray.h>
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2005-04-17 06:20:36 +08:00
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2020-06-02 04:12:05 +08:00
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extern const struct device_type disk_type;
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2007-05-22 04:08:01 +08:00
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extern struct device_type part_type;
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extern struct class block_class;
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2008-08-25 18:56:16 +08:00
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#define DISK_MAX_PARTS 256
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2008-08-25 18:56:17 +08:00
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#define DISK_NAME_LEN 32
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2008-08-25 18:56:16 +08:00
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2010-09-01 04:47:05 +08:00
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#define PARTITION_META_INFO_VOLNAMELTH 64
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2012-11-09 08:12:25 +08:00
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/*
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* Enough for the string representation of any kind of UUID plus NULL.
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* EFI UUID is 36 characters. MSDOS UUID is 11 characters.
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*/
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2016-05-21 08:01:24 +08:00
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#define PARTITION_META_INFO_UUIDLTH (UUID_STRING_LEN + 1)
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2010-09-01 04:47:05 +08:00
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struct partition_meta_info {
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2012-11-09 08:12:25 +08:00
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char uuid[PARTITION_META_INFO_UUIDLTH];
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2010-09-01 04:47:05 +08:00
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u8 volname[PARTITION_META_INFO_VOLNAMELTH];
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};
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2020-03-07 22:56:59 +08:00
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/**
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* DOC: genhd capability flags
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*
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* ``GENHD_FL_REMOVABLE`` (0x0001): indicates that the block device
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* gives access to removable media.
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* When set, the device remains present even when media is not
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* inserted.
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* Must not be set for devices which are removed entirely when the
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* media is removed.
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*
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* ``GENHD_FL_CD`` (0x0008): the block device is a CD-ROM-style
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* device.
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* Affects responses to the ``CDROM_GET_CAPABILITY`` ioctl.
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*
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* ``GENHD_FL_SUPPRESS_PARTITION_INFO`` (0x0020): don't include
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* partition information in ``/proc/partitions`` or in the output of
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* printk_all_partitions().
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* Used for the null block device and some MMC devices.
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*
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* ``GENHD_FL_EXT_DEVT`` (0x0040): the driver supports extended
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* dynamic ``dev_t``, i.e. it wants extended device numbers
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* (``BLOCK_EXT_MAJOR``).
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* This affects the maximum number of partitions.
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*
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* ``GENHD_FL_NATIVE_CAPACITY`` (0x0080): based on information in the
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* partition table, the device's capacity has been extended to its
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* native capacity; i.e. the device has hidden capacity used by one
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* of the partitions (this is a flag used so that native capacity is
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* only ever unlocked once).
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*
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* ``GENHD_FL_BLOCK_EVENTS_ON_EXCL_WRITE`` (0x0100): event polling is
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* blocked whenever a writer holds an exclusive lock.
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*
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* ``GENHD_FL_NO_PART_SCAN`` (0x0200): partition scanning is disabled.
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* Used for loop devices in their default settings and some MMC
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* devices.
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*
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* ``GENHD_FL_HIDDEN`` (0x0400): the block device is hidden; it
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* doesn't produce events, doesn't appear in sysfs, and doesn't have
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* an associated ``bdev``.
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* Implies ``GENHD_FL_SUPPRESS_PARTITION_INFO`` and
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* ``GENHD_FL_NO_PART_SCAN``.
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* Used for multipath devices.
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*/
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#define GENHD_FL_REMOVABLE 0x0001
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/* 2 is unused (used to be GENHD_FL_DRIVERFS) */
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/* 4 is unused (used to be GENHD_FL_MEDIA_CHANGE_NOTIFY) */
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#define GENHD_FL_CD 0x0008
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#define GENHD_FL_SUPPRESS_PARTITION_INFO 0x0020
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#define GENHD_FL_EXT_DEVT 0x0040
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#define GENHD_FL_NATIVE_CAPACITY 0x0080
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#define GENHD_FL_BLOCK_EVENTS_ON_EXCL_WRITE 0x0100
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#define GENHD_FL_NO_PART_SCAN 0x0200
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#define GENHD_FL_HIDDEN 0x0400
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2005-04-17 06:20:36 +08:00
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|
implement in-kernel gendisk events handling
Currently, media presence polling for removeable block devices is done
from userland. There are several issues with this.
* Polling is done by periodically opening the device. For SCSI
devices, the command sequence generated by such action involves a
few different commands including TEST_UNIT_READY. This behavior,
while perfectly legal, is different from Windows which only issues
single command, GET_EVENT_STATUS_NOTIFICATION. Unfortunately, some
ATAPI devices lock up after being periodically queried such command
sequences.
* There is no reliable and unintrusive way for a userland program to
tell whether the target device is safe for media presence polling.
For example, polling for media presence during an on-going burning
session can make it fail. The polling program can avoid this by
opening the device with O_EXCL but then it risks making a valid
exclusive user of the device fail w/ -EBUSY.
* Userland polling is unnecessarily heavy and in-kernel implementation
is lighter and better coordinated (workqueue, timer slack).
This patch implements framework for in-kernel disk event handling,
which includes media presence polling.
* bdops->check_events() is added, which supercedes ->media_changed().
It should check whether there's any pending event and return if so.
Currently, two events are defined - DISK_EVENT_MEDIA_CHANGE and
DISK_EVENT_EJECT_REQUEST. ->check_events() is guaranteed not to be
called parallelly.
* gendisk->events and ->async_events are added. These should be
initialized by block driver before passing the device to add_disk().
The former contains the mask of all supported events and the latter
the mask of all events which the device can report without polling.
/sys/block/*/events[_async] export these to userland.
* Kernel parameter block.events_dfl_poll_msecs controls the system
polling interval (default is 0 which means disable) and
/sys/block/*/events_poll_msecs control polling intervals for
individual devices (default is -1 meaning use system setting). Note
that if a device can report all supported events asynchronously and
its polling interval isn't explicitly set, the device won't be
polled regardless of the system polling interval.
* If a device is opened exclusively with write access, event checking
is automatically disabled until all write exclusive accesses are
released.
* There are event 'clearing' events. For example, both of currently
defined events are cleared after the device has been successfully
opened. This information is passed to ->check_events() callback
using @clearing argument as a hint.
* Event checking is always performed from system_nrt_wq and timer
slack is set to 25% for polling.
* Nothing changes for drivers which implement ->media_changed() but
not ->check_events(). Going forward, all drivers will be converted
to ->check_events() and ->media_change() will be dropped.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-12-09 03:57:37 +08:00
|
|
|
enum {
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|
|
DISK_EVENT_MEDIA_CHANGE = 1 << 0, /* media changed */
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|
DISK_EVENT_EJECT_REQUEST = 1 << 1, /* eject requested */
|
|
|
|
};
|
|
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|
|
2019-03-27 21:51:02 +08:00
|
|
|
enum {
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|
|
/* Poll even if events_poll_msecs is unset */
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|
DISK_EVENT_FLAG_POLL = 1 << 0,
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|
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/* Forward events to udev */
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|
DISK_EVENT_FLAG_UEVENT = 1 << 1,
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|
|
};
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|
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implement in-kernel gendisk events handling
Currently, media presence polling for removeable block devices is done
from userland. There are several issues with this.
* Polling is done by periodically opening the device. For SCSI
devices, the command sequence generated by such action involves a
few different commands including TEST_UNIT_READY. This behavior,
while perfectly legal, is different from Windows which only issues
single command, GET_EVENT_STATUS_NOTIFICATION. Unfortunately, some
ATAPI devices lock up after being periodically queried such command
sequences.
* There is no reliable and unintrusive way for a userland program to
tell whether the target device is safe for media presence polling.
For example, polling for media presence during an on-going burning
session can make it fail. The polling program can avoid this by
opening the device with O_EXCL but then it risks making a valid
exclusive user of the device fail w/ -EBUSY.
* Userland polling is unnecessarily heavy and in-kernel implementation
is lighter and better coordinated (workqueue, timer slack).
This patch implements framework for in-kernel disk event handling,
which includes media presence polling.
* bdops->check_events() is added, which supercedes ->media_changed().
It should check whether there's any pending event and return if so.
Currently, two events are defined - DISK_EVENT_MEDIA_CHANGE and
DISK_EVENT_EJECT_REQUEST. ->check_events() is guaranteed not to be
called parallelly.
* gendisk->events and ->async_events are added. These should be
initialized by block driver before passing the device to add_disk().
The former contains the mask of all supported events and the latter
the mask of all events which the device can report without polling.
/sys/block/*/events[_async] export these to userland.
* Kernel parameter block.events_dfl_poll_msecs controls the system
polling interval (default is 0 which means disable) and
/sys/block/*/events_poll_msecs control polling intervals for
individual devices (default is -1 meaning use system setting). Note
that if a device can report all supported events asynchronously and
its polling interval isn't explicitly set, the device won't be
polled regardless of the system polling interval.
* If a device is opened exclusively with write access, event checking
is automatically disabled until all write exclusive accesses are
released.
* There are event 'clearing' events. For example, both of currently
defined events are cleared after the device has been successfully
opened. This information is passed to ->check_events() callback
using @clearing argument as a hint.
* Event checking is always performed from system_nrt_wq and timer
slack is set to 25% for polling.
* Nothing changes for drivers which implement ->media_changed() but
not ->check_events(). Going forward, all drivers will be converted
to ->check_events() and ->media_change() will be dropped.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-12-09 03:57:37 +08:00
|
|
|
struct disk_events;
|
2016-01-10 00:36:51 +08:00
|
|
|
struct badblocks;
|
implement in-kernel gendisk events handling
Currently, media presence polling for removeable block devices is done
from userland. There are several issues with this.
* Polling is done by periodically opening the device. For SCSI
devices, the command sequence generated by such action involves a
few different commands including TEST_UNIT_READY. This behavior,
while perfectly legal, is different from Windows which only issues
single command, GET_EVENT_STATUS_NOTIFICATION. Unfortunately, some
ATAPI devices lock up after being periodically queried such command
sequences.
* There is no reliable and unintrusive way for a userland program to
tell whether the target device is safe for media presence polling.
For example, polling for media presence during an on-going burning
session can make it fail. The polling program can avoid this by
opening the device with O_EXCL but then it risks making a valid
exclusive user of the device fail w/ -EBUSY.
* Userland polling is unnecessarily heavy and in-kernel implementation
is lighter and better coordinated (workqueue, timer slack).
This patch implements framework for in-kernel disk event handling,
which includes media presence polling.
* bdops->check_events() is added, which supercedes ->media_changed().
It should check whether there's any pending event and return if so.
Currently, two events are defined - DISK_EVENT_MEDIA_CHANGE and
DISK_EVENT_EJECT_REQUEST. ->check_events() is guaranteed not to be
called parallelly.
* gendisk->events and ->async_events are added. These should be
initialized by block driver before passing the device to add_disk().
The former contains the mask of all supported events and the latter
the mask of all events which the device can report without polling.
/sys/block/*/events[_async] export these to userland.
* Kernel parameter block.events_dfl_poll_msecs controls the system
polling interval (default is 0 which means disable) and
/sys/block/*/events_poll_msecs control polling intervals for
individual devices (default is -1 meaning use system setting). Note
that if a device can report all supported events asynchronously and
its polling interval isn't explicitly set, the device won't be
polled regardless of the system polling interval.
* If a device is opened exclusively with write access, event checking
is automatically disabled until all write exclusive accesses are
released.
* There are event 'clearing' events. For example, both of currently
defined events are cleared after the device has been successfully
opened. This information is passed to ->check_events() callback
using @clearing argument as a hint.
* Event checking is always performed from system_nrt_wq and timer
slack is set to 25% for polling.
* Nothing changes for drivers which implement ->media_changed() but
not ->check_events(). Going forward, all drivers will be converted
to ->check_events() and ->media_change() will be dropped.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-12-09 03:57:37 +08:00
|
|
|
|
2015-10-22 01:19:49 +08:00
|
|
|
struct blk_integrity {
|
2017-03-25 09:03:48 +08:00
|
|
|
const struct blk_integrity_profile *profile;
|
|
|
|
unsigned char flags;
|
|
|
|
unsigned char tuple_size;
|
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|
|
unsigned char interval_exp;
|
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|
|
unsigned char tag_size;
|
2015-10-22 01:19:49 +08:00
|
|
|
};
|
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|
|
|
2005-04-17 06:20:36 +08:00
|
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struct gendisk {
|
2008-08-25 18:56:16 +08:00
|
|
|
/* major, first_minor and minors are input parameters only,
|
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|
|
* don't use directly. Use disk_devt() and disk_max_parts().
|
2008-09-03 15:01:48 +08:00
|
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*/
|
2005-04-17 06:20:36 +08:00
|
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|
int major; /* major number of driver */
|
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|
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int first_minor;
|
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|
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int minors; /* maximum number of minors, =1 for
|
|
|
|
* disks that can't be partitioned. */
|
2008-09-03 15:01:48 +08:00
|
|
|
|
2008-08-25 18:56:17 +08:00
|
|
|
char disk_name[DISK_NAME_LEN]; /* name of major driver */
|
implement in-kernel gendisk events handling
Currently, media presence polling for removeable block devices is done
from userland. There are several issues with this.
* Polling is done by periodically opening the device. For SCSI
devices, the command sequence generated by such action involves a
few different commands including TEST_UNIT_READY. This behavior,
while perfectly legal, is different from Windows which only issues
single command, GET_EVENT_STATUS_NOTIFICATION. Unfortunately, some
ATAPI devices lock up after being periodically queried such command
sequences.
* There is no reliable and unintrusive way for a userland program to
tell whether the target device is safe for media presence polling.
For example, polling for media presence during an on-going burning
session can make it fail. The polling program can avoid this by
opening the device with O_EXCL but then it risks making a valid
exclusive user of the device fail w/ -EBUSY.
* Userland polling is unnecessarily heavy and in-kernel implementation
is lighter and better coordinated (workqueue, timer slack).
This patch implements framework for in-kernel disk event handling,
which includes media presence polling.
* bdops->check_events() is added, which supercedes ->media_changed().
It should check whether there's any pending event and return if so.
Currently, two events are defined - DISK_EVENT_MEDIA_CHANGE and
DISK_EVENT_EJECT_REQUEST. ->check_events() is guaranteed not to be
called parallelly.
* gendisk->events and ->async_events are added. These should be
initialized by block driver before passing the device to add_disk().
The former contains the mask of all supported events and the latter
the mask of all events which the device can report without polling.
/sys/block/*/events[_async] export these to userland.
* Kernel parameter block.events_dfl_poll_msecs controls the system
polling interval (default is 0 which means disable) and
/sys/block/*/events_poll_msecs control polling intervals for
individual devices (default is -1 meaning use system setting). Note
that if a device can report all supported events asynchronously and
its polling interval isn't explicitly set, the device won't be
polled regardless of the system polling interval.
* If a device is opened exclusively with write access, event checking
is automatically disabled until all write exclusive accesses are
released.
* There are event 'clearing' events. For example, both of currently
defined events are cleared after the device has been successfully
opened. This information is passed to ->check_events() callback
using @clearing argument as a hint.
* Event checking is always performed from system_nrt_wq and timer
slack is set to 25% for polling.
* Nothing changes for drivers which implement ->media_changed() but
not ->check_events(). Going forward, all drivers will be converted
to ->check_events() and ->media_change() will be dropped.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-12-09 03:57:37 +08:00
|
|
|
|
2019-03-27 21:51:02 +08:00
|
|
|
unsigned short events; /* supported events */
|
|
|
|
unsigned short event_flags; /* flags related to event processing */
|
implement in-kernel gendisk events handling
Currently, media presence polling for removeable block devices is done
from userland. There are several issues with this.
* Polling is done by periodically opening the device. For SCSI
devices, the command sequence generated by such action involves a
few different commands including TEST_UNIT_READY. This behavior,
while perfectly legal, is different from Windows which only issues
single command, GET_EVENT_STATUS_NOTIFICATION. Unfortunately, some
ATAPI devices lock up after being periodically queried such command
sequences.
* There is no reliable and unintrusive way for a userland program to
tell whether the target device is safe for media presence polling.
For example, polling for media presence during an on-going burning
session can make it fail. The polling program can avoid this by
opening the device with O_EXCL but then it risks making a valid
exclusive user of the device fail w/ -EBUSY.
* Userland polling is unnecessarily heavy and in-kernel implementation
is lighter and better coordinated (workqueue, timer slack).
This patch implements framework for in-kernel disk event handling,
which includes media presence polling.
* bdops->check_events() is added, which supercedes ->media_changed().
It should check whether there's any pending event and return if so.
Currently, two events are defined - DISK_EVENT_MEDIA_CHANGE and
DISK_EVENT_EJECT_REQUEST. ->check_events() is guaranteed not to be
called parallelly.
* gendisk->events and ->async_events are added. These should be
initialized by block driver before passing the device to add_disk().
The former contains the mask of all supported events and the latter
the mask of all events which the device can report without polling.
/sys/block/*/events[_async] export these to userland.
* Kernel parameter block.events_dfl_poll_msecs controls the system
polling interval (default is 0 which means disable) and
/sys/block/*/events_poll_msecs control polling intervals for
individual devices (default is -1 meaning use system setting). Note
that if a device can report all supported events asynchronously and
its polling interval isn't explicitly set, the device won't be
polled regardless of the system polling interval.
* If a device is opened exclusively with write access, event checking
is automatically disabled until all write exclusive accesses are
released.
* There are event 'clearing' events. For example, both of currently
defined events are cleared after the device has been successfully
opened. This information is passed to ->check_events() callback
using @clearing argument as a hint.
* Event checking is always performed from system_nrt_wq and timer
slack is set to 25% for polling.
* Nothing changes for drivers which implement ->media_changed() but
not ->check_events(). Going forward, all drivers will be converted
to ->check_events() and ->media_change() will be dropped.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-12-09 03:57:37 +08:00
|
|
|
|
2021-01-24 18:02:41 +08:00
|
|
|
struct xarray part_tbl;
|
2020-11-27 01:47:17 +08:00
|
|
|
struct block_device *part0;
|
2008-09-03 15:03:02 +08:00
|
|
|
|
2009-09-22 08:01:13 +08:00
|
|
|
const struct block_device_operations *fops;
|
2005-04-17 06:20:36 +08:00
|
|
|
struct request_queue *queue;
|
|
|
|
void *private_data;
|
|
|
|
|
|
|
|
int flags;
|
2020-09-21 15:19:45 +08:00
|
|
|
unsigned long state;
|
|
|
|
#define GD_NEED_PART_SCAN 0
|
2021-01-09 18:42:51 +08:00
|
|
|
#define GD_READ_ONLY 1
|
2021-09-29 15:12:40 +08:00
|
|
|
#define GD_DEAD 2
|
2021-05-25 14:12:56 +08:00
|
|
|
|
|
|
|
struct mutex open_mutex; /* open/close mutex */
|
2021-05-25 14:12:59 +08:00
|
|
|
unsigned open_partitions; /* number of open partitions */
|
2021-05-25 14:12:56 +08:00
|
|
|
|
2021-08-09 22:17:43 +08:00
|
|
|
struct backing_dev_info *bdi;
|
2006-03-27 17:17:55 +08:00
|
|
|
struct kobject *slave_dir;
|
2021-08-04 17:41:42 +08:00
|
|
|
#ifdef CONFIG_BLOCK_HOLDER_DEPRECATED
|
|
|
|
struct list_head slave_bdevs;
|
|
|
|
#endif
|
2005-04-17 06:20:36 +08:00
|
|
|
struct timer_rand_state *random;
|
|
|
|
atomic_t sync_io; /* RAID */
|
implement in-kernel gendisk events handling
Currently, media presence polling for removeable block devices is done
from userland. There are several issues with this.
* Polling is done by periodically opening the device. For SCSI
devices, the command sequence generated by such action involves a
few different commands including TEST_UNIT_READY. This behavior,
while perfectly legal, is different from Windows which only issues
single command, GET_EVENT_STATUS_NOTIFICATION. Unfortunately, some
ATAPI devices lock up after being periodically queried such command
sequences.
* There is no reliable and unintrusive way for a userland program to
tell whether the target device is safe for media presence polling.
For example, polling for media presence during an on-going burning
session can make it fail. The polling program can avoid this by
opening the device with O_EXCL but then it risks making a valid
exclusive user of the device fail w/ -EBUSY.
* Userland polling is unnecessarily heavy and in-kernel implementation
is lighter and better coordinated (workqueue, timer slack).
This patch implements framework for in-kernel disk event handling,
which includes media presence polling.
* bdops->check_events() is added, which supercedes ->media_changed().
It should check whether there's any pending event and return if so.
Currently, two events are defined - DISK_EVENT_MEDIA_CHANGE and
DISK_EVENT_EJECT_REQUEST. ->check_events() is guaranteed not to be
called parallelly.
* gendisk->events and ->async_events are added. These should be
initialized by block driver before passing the device to add_disk().
The former contains the mask of all supported events and the latter
the mask of all events which the device can report without polling.
/sys/block/*/events[_async] export these to userland.
* Kernel parameter block.events_dfl_poll_msecs controls the system
polling interval (default is 0 which means disable) and
/sys/block/*/events_poll_msecs control polling intervals for
individual devices (default is -1 meaning use system setting). Note
that if a device can report all supported events asynchronously and
its polling interval isn't explicitly set, the device won't be
polled regardless of the system polling interval.
* If a device is opened exclusively with write access, event checking
is automatically disabled until all write exclusive accesses are
released.
* There are event 'clearing' events. For example, both of currently
defined events are cleared after the device has been successfully
opened. This information is passed to ->check_events() callback
using @clearing argument as a hint.
* Event checking is always performed from system_nrt_wq and timer
slack is set to 25% for polling.
* Nothing changes for drivers which implement ->media_changed() but
not ->check_events(). Going forward, all drivers will be converted
to ->check_events() and ->media_change() will be dropped.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-12-09 03:57:37 +08:00
|
|
|
struct disk_events *ev;
|
2008-07-01 02:04:41 +08:00
|
|
|
#ifdef CONFIG_BLK_DEV_INTEGRITY
|
2015-10-22 01:19:27 +08:00
|
|
|
struct kobject integrity_kobj;
|
2015-10-22 01:19:49 +08:00
|
|
|
#endif /* CONFIG_BLK_DEV_INTEGRITY */
|
2020-04-25 15:57:00 +08:00
|
|
|
#if IS_ENABLED(CONFIG_CDROM)
|
|
|
|
struct cdrom_device_info *cdi;
|
|
|
|
#endif
|
2008-08-25 18:56:15 +08:00
|
|
|
int node_id;
|
2016-01-10 00:36:51 +08:00
|
|
|
struct badblocks *bb;
|
2017-10-25 16:56:05 +08:00
|
|
|
struct lockdep_map lockdep_map;
|
block: add disk sequence number
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.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Matteo Croce <mcroce@microsoft.com>
Tested-by: Luca Boccassi <bluca@debian.org>
Link: https://lore.kernel.org/r/20210712230530.29323-2-mcroce@linux.microsoft.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-07-13 07:05:25 +08:00
|
|
|
u64 diskseq;
|
2005-04-17 06:20:36 +08:00
|
|
|
};
|
|
|
|
|
2021-08-09 14:40:28 +08:00
|
|
|
static inline bool disk_live(struct gendisk *disk)
|
|
|
|
{
|
|
|
|
return !inode_unhashed(disk->part0->bd_inode);
|
|
|
|
}
|
|
|
|
|
2020-11-27 23:43:51 +08:00
|
|
|
/*
|
|
|
|
* The gendisk is refcounted by the part0 block_device, and the bd_device
|
|
|
|
* therein is also used for device model presentation in sysfs.
|
|
|
|
*/
|
|
|
|
#define dev_to_disk(device) \
|
|
|
|
(dev_to_bdev(device)->bd_disk)
|
|
|
|
#define disk_to_dev(disk) \
|
|
|
|
(&((disk)->part0->bd_device))
|
|
|
|
|
2020-04-25 15:57:00 +08:00
|
|
|
#if IS_REACHABLE(CONFIG_CDROM)
|
|
|
|
#define disk_to_cdi(disk) ((disk)->cdi)
|
|
|
|
#else
|
|
|
|
#define disk_to_cdi(disk) NULL
|
|
|
|
#endif
|
|
|
|
|
2008-09-03 15:01:48 +08:00
|
|
|
static inline int disk_max_parts(struct gendisk *disk)
|
|
|
|
{
|
2008-08-25 18:56:16 +08:00
|
|
|
if (disk->flags & GENHD_FL_EXT_DEVT)
|
|
|
|
return DISK_MAX_PARTS;
|
|
|
|
return disk->minors;
|
2008-09-03 15:06:42 +08:00
|
|
|
}
|
|
|
|
|
2011-08-24 02:01:04 +08:00
|
|
|
static inline bool disk_part_scan_enabled(struct gendisk *disk)
|
2008-09-03 15:06:42 +08:00
|
|
|
{
|
2011-08-24 02:01:04 +08:00
|
|
|
return disk_max_parts(disk) > 1 &&
|
|
|
|
!(disk->flags & GENHD_FL_NO_PART_SCAN);
|
2008-09-03 15:01:48 +08:00
|
|
|
}
|
|
|
|
|
|
|
|
static inline dev_t disk_devt(struct gendisk *disk)
|
|
|
|
{
|
2017-11-03 02:29:52 +08:00
|
|
|
return MKDEV(disk->major, disk->first_minor);
|
2008-09-03 15:01:48 +08:00
|
|
|
}
|
|
|
|
|
2021-01-24 18:02:39 +08:00
|
|
|
void disk_uevent(struct gendisk *disk, enum kobject_action action);
|
|
|
|
|
2009-03-10 15:25:54 +08:00
|
|
|
/* block/genhd.c */
|
2021-11-10 08:29:49 +08:00
|
|
|
int __must_check device_add_disk(struct device *parent, struct gendisk *disk,
|
|
|
|
const struct attribute_group **groups);
|
|
|
|
static inline int __must_check add_disk(struct gendisk *disk)
|
2016-06-16 09:17:27 +08:00
|
|
|
{
|
2021-08-18 22:45:40 +08:00
|
|
|
return device_add_disk(NULL, disk, NULL);
|
2016-06-16 09:17:27 +08:00
|
|
|
}
|
2005-04-17 06:20:36 +08:00
|
|
|
extern void del_gendisk(struct gendisk *gp);
|
|
|
|
|
2021-09-22 20:37:08 +08:00
|
|
|
void invalidate_disk(struct gendisk *disk);
|
|
|
|
|
2021-01-09 18:42:51 +08:00
|
|
|
void set_disk_ro(struct gendisk *disk, bool read_only);
|
2005-04-17 06:20:36 +08:00
|
|
|
|
2008-08-25 18:56:10 +08:00
|
|
|
static inline int get_disk_ro(struct gendisk *disk)
|
|
|
|
{
|
2021-01-09 18:42:51 +08:00
|
|
|
return disk->part0->bd_read_only ||
|
|
|
|
test_bit(GD_READ_ONLY, &disk->state);
|
2008-08-25 18:56:10 +08:00
|
|
|
}
|
|
|
|
|
2021-10-06 20:15:04 +08:00
|
|
|
static inline int bdev_read_only(struct block_device *bdev)
|
|
|
|
{
|
|
|
|
return bdev->bd_read_only || get_disk_ro(bdev->bd_disk);
|
|
|
|
}
|
|
|
|
|
implement in-kernel gendisk events handling
Currently, media presence polling for removeable block devices is done
from userland. There are several issues with this.
* Polling is done by periodically opening the device. For SCSI
devices, the command sequence generated by such action involves a
few different commands including TEST_UNIT_READY. This behavior,
while perfectly legal, is different from Windows which only issues
single command, GET_EVENT_STATUS_NOTIFICATION. Unfortunately, some
ATAPI devices lock up after being periodically queried such command
sequences.
* There is no reliable and unintrusive way for a userland program to
tell whether the target device is safe for media presence polling.
For example, polling for media presence during an on-going burning
session can make it fail. The polling program can avoid this by
opening the device with O_EXCL but then it risks making a valid
exclusive user of the device fail w/ -EBUSY.
* Userland polling is unnecessarily heavy and in-kernel implementation
is lighter and better coordinated (workqueue, timer slack).
This patch implements framework for in-kernel disk event handling,
which includes media presence polling.
* bdops->check_events() is added, which supercedes ->media_changed().
It should check whether there's any pending event and return if so.
Currently, two events are defined - DISK_EVENT_MEDIA_CHANGE and
DISK_EVENT_EJECT_REQUEST. ->check_events() is guaranteed not to be
called parallelly.
* gendisk->events and ->async_events are added. These should be
initialized by block driver before passing the device to add_disk().
The former contains the mask of all supported events and the latter
the mask of all events which the device can report without polling.
/sys/block/*/events[_async] export these to userland.
* Kernel parameter block.events_dfl_poll_msecs controls the system
polling interval (default is 0 which means disable) and
/sys/block/*/events_poll_msecs control polling intervals for
individual devices (default is -1 meaning use system setting). Note
that if a device can report all supported events asynchronously and
its polling interval isn't explicitly set, the device won't be
polled regardless of the system polling interval.
* If a device is opened exclusively with write access, event checking
is automatically disabled until all write exclusive accesses are
released.
* There are event 'clearing' events. For example, both of currently
defined events are cleared after the device has been successfully
opened. This information is passed to ->check_events() callback
using @clearing argument as a hint.
* Event checking is always performed from system_nrt_wq and timer
slack is set to 25% for polling.
* Nothing changes for drivers which implement ->media_changed() but
not ->check_events(). Going forward, all drivers will be converted
to ->check_events() and ->media_change() will be dropped.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-12-09 03:57:37 +08:00
|
|
|
extern void disk_block_events(struct gendisk *disk);
|
|
|
|
extern void disk_unblock_events(struct gendisk *disk);
|
2011-07-01 22:17:47 +08:00
|
|
|
extern void disk_flush_events(struct gendisk *disk, unsigned int mask);
|
2020-11-16 22:56:56 +08:00
|
|
|
bool set_capacity_and_notify(struct gendisk *disk, sector_t size);
|
2021-07-13 07:05:29 +08:00
|
|
|
bool disk_force_media_change(struct gendisk *disk, unsigned int events);
|
implement in-kernel gendisk events handling
Currently, media presence polling for removeable block devices is done
from userland. There are several issues with this.
* Polling is done by periodically opening the device. For SCSI
devices, the command sequence generated by such action involves a
few different commands including TEST_UNIT_READY. This behavior,
while perfectly legal, is different from Windows which only issues
single command, GET_EVENT_STATUS_NOTIFICATION. Unfortunately, some
ATAPI devices lock up after being periodically queried such command
sequences.
* There is no reliable and unintrusive way for a userland program to
tell whether the target device is safe for media presence polling.
For example, polling for media presence during an on-going burning
session can make it fail. The polling program can avoid this by
opening the device with O_EXCL but then it risks making a valid
exclusive user of the device fail w/ -EBUSY.
* Userland polling is unnecessarily heavy and in-kernel implementation
is lighter and better coordinated (workqueue, timer slack).
This patch implements framework for in-kernel disk event handling,
which includes media presence polling.
* bdops->check_events() is added, which supercedes ->media_changed().
It should check whether there's any pending event and return if so.
Currently, two events are defined - DISK_EVENT_MEDIA_CHANGE and
DISK_EVENT_EJECT_REQUEST. ->check_events() is guaranteed not to be
called parallelly.
* gendisk->events and ->async_events are added. These should be
initialized by block driver before passing the device to add_disk().
The former contains the mask of all supported events and the latter
the mask of all events which the device can report without polling.
/sys/block/*/events[_async] export these to userland.
* Kernel parameter block.events_dfl_poll_msecs controls the system
polling interval (default is 0 which means disable) and
/sys/block/*/events_poll_msecs control polling intervals for
individual devices (default is -1 meaning use system setting). Note
that if a device can report all supported events asynchronously and
its polling interval isn't explicitly set, the device won't be
polled regardless of the system polling interval.
* If a device is opened exclusively with write access, event checking
is automatically disabled until all write exclusive accesses are
released.
* There are event 'clearing' events. For example, both of currently
defined events are cleared after the device has been successfully
opened. This information is passed to ->check_events() callback
using @clearing argument as a hint.
* Event checking is always performed from system_nrt_wq and timer
slack is set to 25% for polling.
* Nothing changes for drivers which implement ->media_changed() but
not ->check_events(). Going forward, all drivers will be converted
to ->check_events() and ->media_change() will be dropped.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-12-09 03:57:37 +08:00
|
|
|
|
2005-04-17 06:20:36 +08:00
|
|
|
/* drivers/char/random.c */
|
2016-06-21 02:42:34 +08:00
|
|
|
extern void add_disk_randomness(struct gendisk *disk) __latent_entropy;
|
2005-04-17 06:20:36 +08:00
|
|
|
extern void rand_initialize_disk(struct gendisk *disk);
|
|
|
|
|
|
|
|
static inline sector_t get_start_sect(struct block_device *bdev)
|
|
|
|
{
|
2020-11-24 16:34:24 +08:00
|
|
|
return bdev->bd_start_sect;
|
2005-04-17 06:20:36 +08:00
|
|
|
}
|
2020-11-27 01:43:37 +08:00
|
|
|
|
|
|
|
static inline sector_t bdev_nr_sectors(struct block_device *bdev)
|
2005-04-17 06:20:36 +08:00
|
|
|
{
|
2021-10-19 01:39:45 +08:00
|
|
|
return bdev->bd_nr_sectors;
|
2021-10-18 18:11:02 +08:00
|
|
|
}
|
|
|
|
|
2021-10-19 01:39:45 +08:00
|
|
|
static inline loff_t bdev_nr_bytes(struct block_device *bdev)
|
2005-04-17 06:20:36 +08:00
|
|
|
{
|
2021-11-05 01:20:37 +08:00
|
|
|
return (loff_t)bdev_nr_sectors(bdev) << SECTOR_SHIFT;
|
2005-04-17 06:20:36 +08:00
|
|
|
}
|
2020-11-27 01:43:37 +08:00
|
|
|
|
|
|
|
static inline sector_t get_capacity(struct gendisk *disk)
|
2005-04-17 06:20:36 +08:00
|
|
|
{
|
2020-11-27 01:47:17 +08:00
|
|
|
return bdev_nr_sectors(disk->part0);
|
2005-04-17 06:20:36 +08:00
|
|
|
}
|
|
|
|
|
2021-10-18 18:11:25 +08:00
|
|
|
static inline u64 sb_bdev_nr_blocks(struct super_block *sb)
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|
|
|
{
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|
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return bdev_nr_sectors(sb->s_bdev) >>
|
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(sb->s_blocksize_bits - SECTOR_SHIFT);
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}
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2021-06-24 20:32:40 +08:00
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int bdev_disk_changed(struct gendisk *disk, bool invalidate);
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2021-04-06 14:22:55 +08:00
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void blk_drop_partitions(struct gendisk *disk);
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2005-04-17 06:20:36 +08:00
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2021-08-16 21:19:08 +08:00
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struct gendisk *__alloc_disk_node(struct request_queue *q, int node_id,
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struct lock_class_key *lkclass);
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2005-04-17 06:20:36 +08:00
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extern void put_disk(struct gendisk *disk);
|
2021-08-16 21:19:05 +08:00
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struct gendisk *__blk_alloc_disk(int node, struct lock_class_key *lkclass);
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|
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2021-05-21 13:50:55 +08:00
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|
/**
|
|
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|
* blk_alloc_disk - allocate a gendisk structure
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* @node_id: numa node to allocate on
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|
|
*
|
|
|
|
* Allocate and pre-initialize a gendisk structure for use with BIO based
|
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|
* drivers.
|
|
|
|
*
|
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|
|
* Context: can sleep
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|
|
|
*/
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#define blk_alloc_disk(node_id) \
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({ \
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static struct lock_class_key __key; \
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|
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\
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2021-08-16 21:19:05 +08:00
|
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__blk_alloc_disk(node_id, &__key); \
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2021-05-21 13:50:55 +08:00
|
|
|
})
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|
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void blk_cleanup_disk(struct gendisk *disk);
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|
|
|
2020-10-29 22:58:28 +08:00
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|
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int __register_blkdev(unsigned int major, const char *name,
|
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|
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void (*probe)(dev_t devt));
|
|
|
|
#define register_blkdev(major, name) \
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|
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__register_blkdev(major, name, NULL)
|
2020-06-20 15:16:41 +08:00
|
|
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void unregister_blkdev(unsigned int major, const char *name);
|
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|
2020-09-08 22:53:29 +08:00
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|
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bool bdev_check_media_change(struct block_device *bdev);
|
2020-06-20 15:16:41 +08:00
|
|
|
int __invalidate_device(struct block_device *bdev, bool kill_dirty);
|
2020-11-27 01:43:37 +08:00
|
|
|
void set_capacity(struct gendisk *disk, sector_t size);
|
2020-06-20 15:16:41 +08:00
|
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|
|
2021-08-04 17:41:40 +08:00
|
|
|
#ifdef CONFIG_BLOCK_HOLDER_DEPRECATED
|
2020-06-20 15:16:41 +08:00
|
|
|
int bd_link_disk_holder(struct block_device *bdev, struct gendisk *disk);
|
|
|
|
void bd_unlink_disk_holder(struct block_device *bdev, struct gendisk *disk);
|
2021-08-04 17:41:43 +08:00
|
|
|
int bd_register_pending_holders(struct gendisk *disk);
|
2020-06-20 15:16:41 +08:00
|
|
|
#else
|
|
|
|
static inline int bd_link_disk_holder(struct block_device *bdev,
|
|
|
|
struct gendisk *disk)
|
|
|
|
{
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
static inline void bd_unlink_disk_holder(struct block_device *bdev,
|
|
|
|
struct gendisk *disk)
|
|
|
|
{
|
|
|
|
}
|
2021-08-04 17:41:43 +08:00
|
|
|
static inline int bd_register_pending_holders(struct gendisk *disk)
|
|
|
|
{
|
|
|
|
return 0;
|
|
|
|
}
|
2021-08-04 17:41:40 +08:00
|
|
|
#endif /* CONFIG_BLOCK_HOLDER_DEPRECATED */
|
2020-06-20 15:16:41 +08:00
|
|
|
|
2021-05-25 14:13:00 +08:00
|
|
|
dev_t part_devt(struct gendisk *disk, u8 partno);
|
block: add disk sequence number
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.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Matteo Croce <mcroce@microsoft.com>
Tested-by: Luca Boccassi <bluca@debian.org>
Link: https://lore.kernel.org/r/20210712230530.29323-2-mcroce@linux.microsoft.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-07-13 07:05:25 +08:00
|
|
|
void inc_diskseq(struct gendisk *disk);
|
2020-11-15 02:19:57 +08:00
|
|
|
dev_t blk_lookup_devt(const char *name, int partno);
|
2020-11-26 16:23:26 +08:00
|
|
|
void blk_request_module(dev_t devt);
|
2020-06-20 15:16:43 +08:00
|
|
|
#ifdef CONFIG_BLOCK
|
|
|
|
void printk_all_partitions(void);
|
2007-05-11 19:29:54 +08:00
|
|
|
#else /* CONFIG_BLOCK */
|
2020-06-20 15:16:43 +08:00
|
|
|
static inline void printk_all_partitions(void)
|
|
|
|
{
|
|
|
|
}
|
2007-05-11 19:29:54 +08:00
|
|
|
#endif /* CONFIG_BLOCK */
|
[PATCH] BLOCK: Make it possible to disable the block layer [try #6]
Make it possible to disable the block layer. Not all embedded devices require
it, some can make do with just JFFS2, NFS, ramfs, etc - none of which require
the block layer to be present.
This patch does the following:
(*) Introduces CONFIG_BLOCK to disable the block layer, buffering and blockdev
support.
(*) Adds dependencies on CONFIG_BLOCK to any configuration item that controls
an item that uses the block layer. This includes:
(*) Block I/O tracing.
(*) Disk partition code.
(*) All filesystems that are block based, eg: Ext3, ReiserFS, ISOFS.
(*) The SCSI layer. As far as I can tell, even SCSI chardevs use the
block layer to do scheduling. Some drivers that use SCSI facilities -
such as USB storage - end up disabled indirectly from this.
(*) Various block-based device drivers, such as IDE and the old CDROM
drivers.
(*) MTD blockdev handling and FTL.
(*) JFFS - which uses set_bdev_super(), something it could avoid doing by
taking a leaf out of JFFS2's book.
(*) Makes most of the contents of linux/blkdev.h, linux/buffer_head.h and
linux/elevator.h contingent on CONFIG_BLOCK being set. sector_div() is,
however, still used in places, and so is still available.
(*) Also made contingent are the contents of linux/mpage.h, linux/genhd.h and
parts of linux/fs.h.
(*) Makes a number of files in fs/ contingent on CONFIG_BLOCK.
(*) Makes mm/bounce.c (bounce buffering) contingent on CONFIG_BLOCK.
(*) set_page_dirty() doesn't call __set_page_dirty_buffers() if CONFIG_BLOCK
is not enabled.
(*) fs/no-block.c is created to hold out-of-line stubs and things that are
required when CONFIG_BLOCK is not set:
(*) Default blockdev file operations (to give error ENODEV on opening).
(*) Makes some /proc changes:
(*) /proc/devices does not list any blockdevs.
(*) /proc/diskstats and /proc/partitions are contingent on CONFIG_BLOCK.
(*) Makes some compat ioctl handling contingent on CONFIG_BLOCK.
(*) If CONFIG_BLOCK is not defined, makes sys_quotactl() return -ENODEV if
given command other than Q_SYNC or if a special device is specified.
(*) In init/do_mounts.c, no reference is made to the blockdev routines if
CONFIG_BLOCK is not defined. This does not prohibit NFS roots or JFFS2.
(*) The bdflush, ioprio_set and ioprio_get syscalls can now be absent (return
error ENOSYS by way of cond_syscall if so).
(*) The seclvl_bd_claim() and seclvl_bd_release() security calls do nothing if
CONFIG_BLOCK is not set, since they can't then happen.
Signed-Off-By: David Howells <dhowells@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2006-10-01 02:45:40 +08:00
|
|
|
|
2008-03-13 00:52:56 +08:00
|
|
|
#endif /* _LINUX_GENHD_H */
|