summaryrefslogtreecommitdiffstats
Commit message (Collapse)AuthorAgeFilesLines
* dm: update target status functions to support IMA measurementTushar Sugandhi2021-08-1032-2/+328
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | For device mapper targets to take advantage of IMA's measurement capabilities, the status functions for the individual targets need to be updated to handle the status_type_t case for value STATUSTYPE_IMA. Update status functions for the following target types, to log their respective attributes to be measured using IMA. 01. cache 02. crypt 03. integrity 04. linear 05. mirror 06. multipath 07. raid 08. snapshot 09. striped 10. verity For rest of the targets, handle the STATUSTYPE_IMA case by setting the measurement buffer to NULL. For IMA to measure the data on a given system, the IMA policy on the system needs to be updated to have the following line, and the system needs to be restarted for the measurements to take effect. /etc/ima/ima-policy measure func=CRITICAL_DATA label=device-mapper template=ima-buf The measurements will be reflected in the IMA logs, which are located at: /sys/kernel/security/integrity/ima/ascii_runtime_measurements /sys/kernel/security/integrity/ima/binary_runtime_measurements These IMA logs can later be consumed by various attestation clients running on the system, and send them to external services for attesting the system. The DM target data measured by IMA subsystem can alternatively be queried from userspace by setting DM_IMA_MEASUREMENT_FLAG with DM_TABLE_STATUS_CMD. Signed-off-by: Tushar Sugandhi <tusharsu@linux.microsoft.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm ima: measure data on device renameTushar Sugandhi2021-08-103-0/+53
| | | | | | | | | | | | | | A given block device is identified by it's name and UUID. However, both these parameters can be renamed. For an external attestation service to correctly attest a given device, it needs to keep track of these rename events. Update the device data with the new values for IMA measurements. Measure both old and new device name/UUID parameters in the same IMA measurement event, so that the old and the new values can be connected later. Signed-off-by: Tushar Sugandhi <tusharsu@linux.microsoft.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm ima: measure data on table clearTushar Sugandhi2021-08-103-0/+97
| | | | | | | | | | | | | | For a given block device, an inactive table slot contains the parameters to configure the device with. The inactive table can be cleared multiple times, accidentally or maliciously, which may impact the functionality of the device, and compromise the system. Therefore it is important to measure and log the event when a table is cleared. Measure device parameters, and table hashes when the inactive table slot is cleared. Signed-off-by: Tushar Sugandhi <tusharsu@linux.microsoft.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm ima: measure data on device removeTushar Sugandhi2021-08-103-0/+124
| | | | | | | | | | | | | Presence of an active block-device, configured with expected parameters, is important for an external attestation service to determine if a system meets the attestation requirements. Therefore it is important for DM to measure the device remove events. Measure device parameters and table hashes when the device is removed, using either remove or remove_all. Signed-off-by: Tushar Sugandhi <tusharsu@linux.microsoft.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm ima: measure data on device resumeTushar Sugandhi2021-08-103-2/+125
| | | | | | | | | | | | | | | | | | | | A given block device can load a table multiple times, with different input parameters, before eventually resuming it. Further, a device may be suspended and then resumed. The device may never resume after a table-load. Because of the above valid scenarios for a given device, it is important to measure and log the device resume event using IMA. Also, if the table is large, measuring it in clear-text each time the device changes state, will unnecessarily increase the size of IMA log. Since the table clear-text is already measured during table-load event, measuring the hash during resume should be sufficient to validate the table contents. Measure the device parameters, and hash of the active table, when the device is resumed. Signed-off-by: Tushar Sugandhi <tusharsu@linux.microsoft.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm ima: measure data on table loadTushar Sugandhi2021-08-109-2/+415
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | DM configures a block device with various target specific attributes passed to it as a table. DM loads the table, and calls each target’s respective constructors with the attributes as input parameters. Some of these attributes are critical to ensure the device meets certain security bar. Thus, IMA should measure these attributes, to ensure they are not tampered with, during the lifetime of the device. So that the external services can have high confidence in the configuration of the block-devices on a given system. Some devices may have large tables. And a given device may change its state (table-load, suspend, resume, rename, remove, table-clear etc.) many times. Measuring these attributes each time when the device changes its state will significantly increase the size of the IMA logs. Further, once configured, these attributes are not expected to change unless a new table is loaded, or a device is removed and recreated. Therefore the clear-text of the attributes should only be measured during table load, and the hash of the active/inactive table should be measured for the remaining device state changes. Export IMA function ima_measure_critical_data() to allow measurement of DM device parameters, as well as target specific attributes, during table load. Compute the hash of the inactive table and store it for measurements during future state change. If a load is called multiple times, update the inactive table hash with the hash of the latest populated table. So that the correct inactive table hash is measured when the device transitions to different states like resume, remove, rename, etc. Signed-off-by: Tushar Sugandhi <tusharsu@linux.microsoft.com> Signed-off-by: Colin Ian King <colin.king@canonical.com> # leak fix Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm writecache: add event countersMikulas Patocka2021-08-102-5/+67
| | | | | | | | | Add 10 counters for various events (hit, miss, etc) and export them in the status line (accessed from userspace with "dmsetup status"). Also add a message "clear_stats" that resets these counters. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm writecache: report invalid return from writecache_map helpersMikulas Patocka2021-08-101-1/+4
| | | | | | | | If some "writecache_map_*" function returns invalid state, it is a bug. So, we should report it and not fail silently. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm writecache: further writecache_map() cleanupMike Snitzer2021-08-101-32/+43
| | | | | | | | Factor out writecache_map_flush() and writecache_map_discard() from writecache_map(). Also eliminate the various goto labels in writecache_map(). Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm writecache: factor out writecache_map_remap_origin()Mike Snitzer2021-08-101-15/+15
| | | | Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm writecache: split up writecache_map() to improve code readabilityMike Snitzer2021-08-101-151/+187
| | | | | | | writecache_map() has grown too large and can be confusing to read given all the goto statements. Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* writeback: make the laptop_mode prototypes available unconditionallyChristoph Hellwig2021-08-101-5/+0
| | | | | | | | | Fix the !CONFIG_BLOCK build after the recent cleanup. Fixes: 5ed964f8e54e ("mm: hide laptop_mode_wb_timer entirely behind the BDI API") Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
* block: return ELEVATOR_DISCARD_MERGE if possibleMing Lei2021-08-095-16/+24
| | | | | | | | | | | | | | | | | | When merging one bio to request, if they are discard IO and the queue supports multi-range discard, we need to return ELEVATOR_DISCARD_MERGE because both block core and related drivers(nvme, virtio-blk) doesn't handle mixed discard io merge(traditional IO merge together with discard merge) well. Fix the issue by returning ELEVATOR_DISCARD_MERGE in this situation, so both blk-mq and drivers just need to handle multi-range discard. Reported-by: Oleksandr Natalenko <oleksandr@natalenko.name> Signed-off-by: Ming Lei <ming.lei@redhat.com> Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name> Fixes: 2705dfb20947 ("block: fix discard request merge") Link: https://lore.kernel.org/r/20210729034226.1591070-1-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
* block: remove the bd_bdi in struct block_deviceChristoph Hellwig2021-08-097-20/+9
| | | | | | | | | | Just retrieve the bdi from the disk. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Link: https://lore.kernel.org/r/20210809141744.1203023-6-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* block: move the bdi from the request_queue to the gendiskChristoph Hellwig2021-08-0914-63/+58
| | | | | | | | | | | The backing device information only makes sense for file system I/O, and thus belongs into the gendisk and not the lower level request_queue structure. Move it there. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Link: https://lore.kernel.org/r/20210809141744.1203023-5-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* block: add a queue_has_disk helperChristoph Hellwig2021-08-091-0/+1
| | | | | | | | | | Add a helper to check if a gendisk is associated with a request_queue. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Link: https://lore.kernel.org/r/20210809141744.1203023-4-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* block: pass a gendisk to blk_queue_update_readaheadChristoph Hellwig2021-08-096-8/+10
| | | | | | | | | | | .. and rename the function to disk_update_readahead. This is in preparation for moving the BDI from the request_queue to the gendisk. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Link: https://lore.kernel.org/r/20210809141744.1203023-3-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* mm: hide laptop_mode_wb_timer entirely behind the BDI APIChristoph Hellwig2021-08-093-7/+3
| | | | | | | | | | | | | Don't leak the detaіls of the timer into the block layer, instead initialize the timer in bdi_alloc and delete it in bdi_unregister. Note that this means the timer is initialized (but not armed) for non-block queues as well now. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Link: https://lore.kernel.org/r/20210809141744.1203023-2-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* block: remove support for delayed queue registrationsChristoph Hellwig2021-08-093-29/+7
| | | | | | | | | | Now that device mapper has been changed to register the disk once it is fully ready all this code is unused. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Mike Snitzer <snitzer@redhat.com> Link: https://lore.kernel.org/r/20210804094147.459763-9-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* dm: delay registering the gendiskChristoph Hellwig2021-08-092-13/+11
| | | | | | | | | | | | | | | | device mapper is currently the only outlier that tries to call register_disk after add_disk, leading to fairly inconsistent state of these block layer data structures. Instead change device-mapper to just register the gendisk later now that the holder mechanism can cope with that. Note that this introduces a user visible change: the dm kobject is now only visible after the initial table has been loaded. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Mike Snitzer <snitzer@redhat.com> Link: https://lore.kernel.org/r/20210804094147.459763-8-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* dm: move setting md->type into dm_setup_md_queueChristoph Hellwig2021-08-092-6/+3
| | | | | | | | | | | Move setting md->type from both callers into dm_setup_md_queue. This ensures that md->type is only set to a valid value after the queue has been fully setup, something we'll rely on future changes. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Mike Snitzer <snitzer@redhat.com> Link: https://lore.kernel.org/r/20210804094147.459763-7-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* dm: cleanup cleanup_mapped_deviceChristoph Hellwig2021-08-091-5/+1
| | | | | | | | | | md->queue is now always set when md->disk is set, so simplify the conditionals a bit. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Mike Snitzer <snitzer@redhat.com> Link: https://lore.kernel.org/r/20210804094147.459763-6-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* block: support delayed holder registrationChristoph Hellwig2021-08-093-17/+66
| | | | | | | | | | | | | | | | | device mapper needs to register holders before it is ready to do I/O. Currently it does so by registering the disk early, which can leave the disk and queue in a weird half state where the queue is registered with the disk, except for sysfs and the elevator. And this state has been a bit promlematic before, and will get more so when sorting out the responsibilities between the queue and the disk. Support registering holders on an initialized but not registered disk instead by delaying the sysfs registration until the disk is registered. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Mike Snitzer <snitzer@redhat.com> Link: https://lore.kernel.org/r/20210804094147.459763-5-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* block: look up holders by bdevChristoph Hellwig2021-08-095-17/+15
| | | | | | | | | Invert they way the holder relations are tracked. This very slightly reduces the memory overhead for partitioned devices. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20210804094147.459763-4-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* block: remove the extra kobject reference in bd_link_disk_holderChristoph Hellwig2021-08-091-6/+0
| | | | | | | | | | | Since commit 0d02129e76ed ("block: merge struct block_device and struct hd_struct") there is no way for the bdev to go away as long as there is a holder, so remove the extra references. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Mike Snitzer <snitzer@redhat.com> Link: https://lore.kernel.org/r/20210804094147.459763-3-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* block: make the block holder code optionalChristoph Hellwig2021-08-098-146/+151
| | | | | | | | | | | | | | | | Move the block holder code into a separate file as it is not in any way related to the other block_dev.c code, and add a new selectable config option for it so that we don't have to build it without any remapped drivers selected. The Kconfig symbol contains a _DEPRECATED suffix to match the comments added in commit 49731baa41df ("block: restore multiple bd_link_disk_holder() support"). Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Mike Snitzer <snitzer@redhat.com> Link: https://lore.kernel.org/r/20210804094147.459763-2-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* loop: Select I/O scheduler 'none' from inside add_disk()Bart Van Assche2021-08-051-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We noticed that the user interface of Android devices becomes very slow under memory pressure. This is because Android uses the zram driver on top of the loop driver for swapping, because under memory pressure the swap code alternates reads and writes quickly, because mq-deadline is the default scheduler for loop devices and because mq-deadline delays writes by five seconds for such a workload with default settings. Fix this by making the kernel select I/O scheduler 'none' from inside add_disk() for loop devices. This default can be overridden at any time from user space, e.g. via a udev rule. This approach has an advantage compared to changing the I/O scheduler from userspace from 'mq-deadline' into 'none', namely that synchronize_rcu() does not get called. This patch changes the default I/O scheduler for loop devices from 'mq-deadline' into 'none'. Additionally, this patch reduces the Android boot time on my test setup with 0.5 seconds compared to configuring the loop I/O scheduler from user space. Cc: Christoph Hellwig <hch@lst.de> Cc: Ming Lei <ming.lei@redhat.com> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Martijn Coenen <maco@android.com> Cc: Jaegeuk Kim <jaegeuk@kernel.org> Signed-off-by: Bart Van Assche <bvanassche@acm.org> Link: https://lore.kernel.org/r/20210805174200.3250718-3-bvanassche@acm.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
* blk-mq: Introduce the BLK_MQ_F_NO_SCHED_BY_DEFAULT flagBart Van Assche2021-08-052-0/+9
| | | | | | | | | | | | | | | | | | | | | elevator_get_default() uses the following algorithm to select an I/O scheduler from inside add_disk(): - In case of a single hardware queue or if sharing hardware queues across multiple request queues (BLK_MQ_F_TAG_HCTX_SHARED), use mq-deadline. - Otherwise, use 'none'. This is a good choice for most but not for all block drivers. Make it possible to override the selection of mq-deadline with a new flag, namely BLK_MQ_F_NO_SCHED_BY_DEFAULT. Cc: Christoph Hellwig <hch@lst.de> Cc: Ming Lei <ming.lei@redhat.com> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Martijn Coenen <maco@android.com> Cc: Jaegeuk Kim <jaegeuk@kernel.org> Signed-off-by: Bart Van Assche <bvanassche@acm.org> Link: https://lore.kernel.org/r/20210805174200.3250718-2-bvanassche@acm.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
* block: remove blk-mq-sysfs dead codeDamien Le Moal2021-08-021-55/+0
| | | | | | | | | | | | In block/blk-mq-sysfs.c, struct blk_mq_ctx_sysfs_entry is not used to define any attribute since the "mq" sysfs directory contains only sub-directories (no attribute files). As a result, blk_mq_sysfs_show(), blk_mq_sysfs_store(), and struct sysfs_ops blk_mq_sysfs_ops are all unused and unnecessary. Remove all this unused code. Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com> Link: https://lore.kernel.org/r/20210713081837.524422-1-damien.lemoal@wdc.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
* loop: raise media_change eventMatteo Croce2021-08-021-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Make the loop device raise a DISK_MEDIA_CHANGE event on attach or detach. # udevadm monitor -up |grep -e DISK_MEDIA_CHANGE -e DEVNAME & # losetup -f zero [ 7.454235] loop0: detected capacity change from 0 to 16384 DISK_MEDIA_CHANGE=1 DEVNAME=/dev/loop0 DEVNAME=/dev/loop0 DEVNAME=/dev/loop0 # losetup -f zero [ 10.205245] loop1: detected capacity change from 0 to 16384 DISK_MEDIA_CHANGE=1 DEVNAME=/dev/loop1 DEVNAME=/dev/loop1 DEVNAME=/dev/loop1 # losetup -f zero2 [ 13.532368] loop2: detected capacity change from 0 to 40960 DISK_MEDIA_CHANGE=1 DEVNAME=/dev/loop2 DEVNAME=/dev/loop2 # losetup -D DEVNAME=/dev/loop1 DISK_MEDIA_CHANGE=1 DEVNAME=/dev/loop1 DEVNAME=/dev/loop2 DISK_MEDIA_CHANGE=1 DEVNAME=/dev/loop2 DEVNAME=/dev/loop0 DISK_MEDIA_CHANGE=1 DEVNAME=/dev/loop0 Signed-off-by: Matteo Croce <mcroce@microsoft.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Tested-by: Luca Boccassi <bluca@debian.org> Link: https://lore.kernel.org/r/20210712230530.29323-7-mcroce@linux.microsoft.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
* block: add a helper to raise a media changed eventMatteo Croce2021-08-022-15/+47
| | | | | | | | | | | | | Refactor disk_check_events() and move some code into disk_event_uevent(). Then add disk_force_media_change(), a helper which will be used by devices to force issuing a DISK_EVENT_MEDIA_CHANGE event. Co-developed-by: Christoph Hellwig <hch@lst.de> Signed-off-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/20210712230530.29323-6-mcroce@linux.microsoft.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
* block: export diskseq in sysfsMatteo Croce2021-08-022-0/+22
| | | | | | | | | | | | | | | | | | | | Add a new sysfs handle to export the new diskseq value. Place it in <sysfs>/block/<disk>/diskseq and document it. $ grep . /sys/class/block/*/diskseq /sys/class/block/loop0/diskseq:13 /sys/class/block/loop1/diskseq:14 /sys/class/block/loop2/diskseq:5 /sys/class/block/loop3/diskseq:6 /sys/class/block/ram0/diskseq:1 /sys/class/block/ram1/diskseq:2 /sys/class/block/vda/diskseq:7 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/20210712230530.29323-5-mcroce@linux.microsoft.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
* block: add ioctl to read the disk sequence numberMatteo Croce2021-08-022-0/+3
| | | | | | | | | | | | | | | | | | | | | | Add a new BLKGETDISKSEQ ioctl which retrieves the disk sequence number from the genhd structure. # ./getdiskseq /dev/loop* /dev/loop0: 13 /dev/loop0p1: 13 /dev/loop0p2: 13 /dev/loop0p3: 13 /dev/loop1: 14 /dev/loop1p1: 14 /dev/loop1p2: 14 /dev/loop2: 5 /dev/loop3: 6 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/20210712230530.29323-4-mcroce@linux.microsoft.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
* block: export the diskseq in ueventsMatteo Croce2021-08-021-0/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Export the newly introduced diskseq in uevents: $ udevadm info /sys/class/block/* |grep -e DEVNAME -e DISKSEQ E: DEVNAME=/dev/loop0 E: DISKSEQ=1 E: DEVNAME=/dev/loop1 E: DISKSEQ=2 E: DEVNAME=/dev/loop2 E: DISKSEQ=3 E: DEVNAME=/dev/loop3 E: DISKSEQ=4 E: DEVNAME=/dev/loop4 E: DISKSEQ=5 E: DEVNAME=/dev/loop5 E: DISKSEQ=6 E: DEVNAME=/dev/loop6 E: DISKSEQ=7 E: DEVNAME=/dev/loop7 E: DISKSEQ=8 E: DEVNAME=/dev/nvme0n1 E: DISKSEQ=9 E: DEVNAME=/dev/nvme0n1p1 E: DISKSEQ=9 E: DEVNAME=/dev/nvme0n1p2 E: DISKSEQ=9 E: DEVNAME=/dev/nvme0n1p3 E: DISKSEQ=9 E: DEVNAME=/dev/nvme0n1p4 E: DISKSEQ=9 E: DEVNAME=/dev/nvme0n1p5 E: DISKSEQ=9 E: DEVNAME=/dev/sda E: DISKSEQ=10 E: DEVNAME=/dev/sda1 E: DISKSEQ=10 E: DEVNAME=/dev/sda2 E: DISKSEQ=10 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/20210712230530.29323-3-mcroce@linux.microsoft.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
* block: add disk sequence numberMatteo Croce2021-08-023-0/+29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* block: remove cmdline-parser.cChristoph Hellwig2021-08-027-319/+262
| | | | | | | | | cmdline-parser.c is only used by the cmdline faux partition format, so merge the code into that and avoid an indirect call. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20210728053756.409654-1-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* block: remove disk_name()Christoph Hellwig2021-08-022-9/+9
| | | | | | | | | Remove the disk_name function now that all users are gone. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Link: https://lore.kernel.org/r/20210727062518.122108-7-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* block: simplify disk name formatting in check_partitionChristoph Hellwig2021-08-021-1/+1
| | | | | | | | | | disk_name for partition 0 just copies out the disk_name field. Replace the call to disk_name with a %s format specifier. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Link: https://lore.kernel.org/r/20210727062518.122108-6-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* block: simplify printing the device names disk_stack_limitsChristoph Hellwig2021-08-021-9/+3
| | | | | | | | | | Printk ->disk_name directly for the disk and use the %pg format specifier for the block device, which is equivalent to a bdevname call. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Link: https://lore.kernel.org/r/20210727062518.122108-5-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* block: use the %pg format specifier in show_partitionChristoph Hellwig2021-08-021-4/+2
| | | | | | | | | | Simplify printing the partition name by using the %pg format specifier that is equivalent to a bdevname call. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Link: https://lore.kernel.org/r/20210727062518.122108-4-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* block: use the %pg format specifier in printk_all_partitionsChristoph Hellwig2021-08-021-4/+2
| | | | | | | | | | Simplify printing the partition name by using the %pg format specifier that is equivalent to a bdevname call. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Link: https://lore.kernel.org/r/20210727062518.122108-3-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* block: reduce stack usage in diskstats_showAbd-Alrhman Masalkhi2021-08-021-4/+2
| | | | | | | | | | | | | | | | | | | | I have compiled the kernel with a cross compiler "hppa-linux-gnu-" v9.3.0 on x86-64 host machine. I got the following warning: block/genhd.c: In function ‘diskstats_show’: block/genhd.c:1227:1: warning: the frame size of 1688 bytes is larger than 1280 bytes [-Wframe-larger-than=] 1227 | } By Reduced the stack footprint by using the %pg printk specifier instead of disk_name to remove the need for the on-stack buffer. Signed-off-by: Abd-Alrhman Masalkhi <abd.masalkhi@gmail.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Link: https://lore.kernel.org/r/20210727062518.122108-2-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* block: remove bdputChristoph Hellwig2021-08-024-10/+3
| | | | | | | | | | | | Now that we've stopped using inode references for anything meaninful in the block layer get rid of the helper to put it and just open code the call to iput on the block_device inode. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: Chaitanya Kulkarni <ckulkarnilinux@gmail.com> Link: https://lore.kernel.org/r/20210722075402.983367-10-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* block: remove bdgrabChristoph Hellwig2021-08-022-16/+0
| | | | | | | | | | All callers are gone, and no one should grab a pure inode reference to a block device anymore. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Link: https://lore.kernel.org/r/20210722075402.983367-9-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* loop: don't grab a reference to the block deviceChristoph Hellwig2021-08-021-5/+0
| | | | | | | | | | | | The whole device block device won't be removed while the disk is still alive, so don't bother to grab a reference to it. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: Ming Lei <ming.lei@rehat.com> Reviewed-by: Chaitanya Kulkarni <ckulkarnilinux@gmail.com> Link: https://lore.kernel.org/r/20210722075402.983367-8-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* block: change the refcounting for partitionsChristoph Hellwig2021-08-022-38/+31
| | | | | | | | | | | Instead of acquiring an inode reference on open make sure partitions always hold device model references to the disk while alive, and switch open to grab only a device model reference to the opened block device. If that is a partition the disk reference is transitively held by the partition already. Link: https://lore.kernel.org/r/20210722075402.983367-6-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* block: allocate bd_meta_info later in add_partitionsChristoph Hellwig2021-08-021-10/+7
| | | | | | | | | | Move the allocation of bd_meta_info after initializing the struct device to avoid the special bdput error handling path. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20210722075402.983367-5-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* block: unhash the whole device inode earlierChristoph Hellwig2021-08-022-7/+2
| | | | | | | | | | | Unhash the whole device inode early in del_gendisk. This allows to remove the first GENHD_FL_UP check in the open path as we simply won't find a just removed inode. The second non-racy check after taking open_mutex is still kept. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20210722075402.983367-4-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* block: assert the locking state in delete_partitionChristoph Hellwig2021-08-021-4/+2
| | | | | | | | | | | Add a lockdep assert instead of the outdated locking comment. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: Ming Lei <ming.lei@redhat.com> Reviewed-by: Chaitanya Kulkarni <ckulkarnilinux@gmail.com> Link: https://lore.kernel.org/r/20210722075402.983367-3-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* block: use bvec_kmap_local in bio_integrity_processChristoph Hellwig2021-08-021-8/+6
| | | | | | | | | | Using local kmaps slightly reduces the chances to stray writes, and the bvec interface cleans up the code a little bit. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Link: https://lore.kernel.org/r/20210727055646.118787-16-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>