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authorLinus Torvalds <torvalds@linux-foundation.org>2020-03-30 11:20:13 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2020-03-30 11:20:13 -0700
commit10f36b1e80a9f7afdaefe6f0b06dcdf89715eed7 (patch)
treeb47a3af19ab20a7cd6c1578db4afba1a85a8ec5b /Documentation
parentMerge tag 'for-5.7/libata-2020-03-29' of git://git.kernel.dk/linux-block (diff)
parentblock: return NULL in blk_alloc_queue() on error (diff)
downloadlinux-dev-10f36b1e80a9f7afdaefe6f0b06dcdf89715eed7.tar.xz
linux-dev-10f36b1e80a9f7afdaefe6f0b06dcdf89715eed7.zip
Merge tag 'for-5.7/block-2020-03-29' of git://git.kernel.dk/linux-block
Pull block updates from Jens Axboe: - Online capacity resizing (Balbir) - Number of hardware queue change fixes (Bart) - null_blk fault injection addition (Bart) - Cleanup of queue allocation, unifying the node/no-node API (Christoph) - Cleanup of genhd, moving code to where it makes sense (Christoph) - Cleanup of the partition handling code (Christoph) - disk stat fixes/improvements (Konstantin) - BFQ improvements (Paolo) - Various fixes and improvements * tag 'for-5.7/block-2020-03-29' of git://git.kernel.dk/linux-block: (72 commits) block: return NULL in blk_alloc_queue() on error block: move bio_map_* to blk-map.c Revert "blkdev: check for valid request queue before issuing flush" block: simplify queue allocation bcache: pass the make_request methods to blk_queue_make_request null_blk: use blk_mq_init_queue_data block: add a blk_mq_init_queue_data helper block: move the ->devnode callback to struct block_device_operations block: move the part_stat* helpers from genhd.h to a new header block: move block layer internals out of include/linux/genhd.h block: move guard_bio_eod to bio.c block: unexport get_gendisk block: unexport disk_map_sector_rcu block: unexport disk_get_part block: mark part_in_flight and part_in_flight_rw static block: mark block_depr static block: factor out requeue handling from dispatch code block/diskstats: replace time_in_queue with sum of request times block/diskstats: accumulate all per-cpu counters in one pass block/diskstats: more accurate approximation of io_ticks for slow disks ...
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/admin-guide/iostats.rst5
-rw-r--r--Documentation/block/capability.rst16
-rw-r--r--Documentation/scsi/scsi_mid_low_api.txt21
3 files changed, 8 insertions, 34 deletions
diff --git a/Documentation/admin-guide/iostats.rst b/Documentation/admin-guide/iostats.rst
index df5b8345c41d..9b14b0c2c9c4 100644
--- a/Documentation/admin-guide/iostats.rst
+++ b/Documentation/admin-guide/iostats.rst
@@ -100,7 +100,7 @@ Field 10 -- # of milliseconds spent doing I/Os (unsigned int)
Since 5.0 this field counts jiffies when at least one request was
started or completed. If request runs more than 2 jiffies then some
- I/O time will not be accounted unless there are other requests.
+ I/O time might be not accounted in case of concurrent requests.
Field 11 -- weighted # of milliseconds spent doing I/Os (unsigned int)
This field is incremented at each I/O start, I/O completion, I/O
@@ -143,6 +143,9 @@ are summed (possibly overflowing the unsigned long variable they are
summed to) and the result given to the user. There is no convenient
user interface for accessing the per-CPU counters themselves.
+Since 4.19 request times are measured with nanoseconds precision and
+truncated to milliseconds before showing in this interface.
+
Disks vs Partitions
-------------------
diff --git a/Documentation/block/capability.rst b/Documentation/block/capability.rst
index 2cf258d64bbe..160a5148b915 100644
--- a/Documentation/block/capability.rst
+++ b/Documentation/block/capability.rst
@@ -2,17 +2,9 @@
Generic Block Device Capability
===============================
-This file documents the sysfs file block/<disk>/capability
+This file documents the sysfs file ``block/<disk>/capability``.
-capability is a hex word indicating which capabilities a specific disk
-supports. For more information on bits not listed here, see
-include/linux/genhd.h
+``capability`` is a bitfield, printed in hexadecimal, indicating which
+capabilities a specific block device supports:
-GENHD_FL_MEDIA_CHANGE_NOTIFY
-----------------------------
-
-Value: 4
-
-When this bit is set, the disk supports Asynchronous Notification
-of media change events. These events will be broadcast to user
-space via kernel uevent.
+.. kernel-doc:: include/linux/genhd.h
diff --git a/Documentation/scsi/scsi_mid_low_api.txt b/Documentation/scsi/scsi_mid_low_api.txt
index 2a4be1c3e6db..537f04728487 100644
--- a/Documentation/scsi/scsi_mid_low_api.txt
+++ b/Documentation/scsi/scsi_mid_low_api.txt
@@ -299,7 +299,6 @@ Summary:
scsi_host_alloc - return a new scsi_host instance whose refcount==1
scsi_host_get - increments Scsi_Host instance's refcount
scsi_host_put - decrements Scsi_Host instance's refcount (free if 0)
- scsi_partsize - parse partition table into cylinders, heads + sectors
scsi_register - create and register a scsi host adapter instance.
scsi_remove_device - detach and remove a SCSI device
scsi_remove_host - detach and remove all SCSI devices owned by host
@@ -473,26 +472,6 @@ void scsi_host_put(struct Scsi_Host *shost)
/**
- * scsi_partsize - parse partition table into cylinders, heads + sectors
- * @buf: pointer to partition table
- * @capacity: size of (total) disk in 512 byte sectors
- * @cyls: outputs number of cylinders calculated via this pointer
- * @hds: outputs number of heads calculated via this pointer
- * @secs: outputs number of sectors calculated via this pointer
- *
- * Returns 0 on success, -1 on failure
- *
- * Might block: no
- *
- * Notes: Caller owns memory returned (free with kfree() )
- *
- * Defined in: drivers/scsi/scsicam.c
- **/
-int scsi_partsize(unsigned char *buf, unsigned long capacity,
- unsigned int *cyls, unsigned int *hds, unsigned int *secs)
-
-
-/**
* scsi_register - create and register a scsi host adapter instance.
* @sht: pointer to scsi host template
* @privsize: extra bytes to allocate in hostdata array (which is the