block: pass a queue_limits argument to blk_alloc_disk

Pass a queue_limits to blk_alloc_disk and apply it if non-NULL. This
will allow allocating queues with valid queue limits instead of setting
the values one at a time later.

Also change blk_alloc_disk to return an ERR_PTR instead of just NULL
which can't distinguish errors.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Link: https://lore.kernel.org/r/20240215071055.2201424-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: replace fmode_t with a block-specific type for block open flags

The only overlap between the block open flags mapped into the fmode_t and
other uses of fmode_t are FMODE_READ and FMODE_WRITE. Define a new
blk_mode_t instead for use in blkdev_get_by_{dev,path}, ->open and
->ioctl and stop abusing fmode_t.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Jack Wang <jinpu.wang@ionos.com> [rnbd]
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Christian Brauner <brauner@kernel.org>
Link: https://lore.kernel.org/r/20230608110258.189493-28-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: remove the unused mode argument to ->release

The mode argument to the ->release block_device_operation is never used,
so remove it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Acked-by: Christian Brauner <brauner@kernel.org>
Acked-by: Jack Wang <jinpu.wang@ionos.com> [rnbd]
Link: https://lore.kernel.org/r/20230608110258.189493-10-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: pass a gendisk to ->open

->open is only called on the whole device. Make that explicit by
passing a gendisk instead of the block_device.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Acked-by: Christian Brauner <brauner@kernel.org>
Acked-by: Jack Wang <jinpu.wang@ionos.com> [rnbd]
Link: https://lore.kernel.org/r/20230608110258.189493-9-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: remove blk_cleanup_disk

blk_cleanup_disk is nothing but a trivial wrapper for put_disk now,
so remove it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Link: https://lore.kernel.org/r/20220619060552.1850436-7-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

xtensa/simdisk: fix proc_read_simdisk()

The commit a69755b18774 ("xtensa simdisk: switch to proc_create_data()")
split read operation into two parts, first retrieving the path when it's
non-null and second retrieving the trailing '\n'. However when the path
is non-null the first simple_read_from_buffer updates ppos, and the
second simple_read_from_buffer returns 0 if ppos is greater than 1 (i.e.
almost always). As a result reading from that proc file is almost always
empty.

Fix it by making a temporary copy of the path with the trailing '\n' and
using simple_read_from_buffer on that copy.

Cc: stable@vger.kernel.org
Fixes: a69755b18774 ("xtensa simdisk: switch to proc_create_data()")
Signed-off-by: Yi Yang <yiyang13@huawei.com>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

iss-simdisk: use bvec_kmap_local in simdisk_submit_bio

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: Ira Weiny <ira.weiny@intel.com>
Acked-by: Max Filippov <jcmvbkbc@gmail.com>
Link: https://lore.kernel.org/r/20220303111905.321089-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

proc: remove PDE_DATA() completely

Remove PDE_DATA() completely and replace it with pde_data().

[akpm@linux-foundation.org: fix naming clash in drivers/nubus/proc.c]
[akpm@linux-foundation.org: now fix it properly]

Link: https://lkml.kernel.org/r/20211124081956.87711-2-songmuchun@bytedance.com
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Alexey Gladkov <gladkov.alexey@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

xtensa/platforms/iss/simdisk: add error handling support for add_disk()

We never checked for errors on add_disk() as this function
returned void. Now that this is fixed, use the shiny new
error handling.

Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Acked-by: Max Filippov <jcmvbkbc@gmail.com>
Link: https://lore.kernel.org/r/20210927220110.1066271-7-mcgrof@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: switch polling to be bio based

Replace the blk_poll interface that requires the caller to keep a queue
and cookie from the submissions with polling based on the bio.

Polling for the bio itself leads to a few advantages:

- the cookie construction can made entirely private in blk-mq.c
- the caller does not need to remember the request_queue and cookie
separately and thus sidesteps their lifetime issues
- keeping the device and the cookie inside the bio allows to trivially
support polling BIOs remapping by stacking drivers
- a lot of code to propagate the cookie back up the submission path can
be removed entirely.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Mark Wunderlich <mark.wunderlich@intel.com>
Link: https://lore.kernel.org/r/20211012111226.760968-15-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

simdisk: convert to blk_alloc_disk/blk_cleanup_disk

Convert the simdisk driver to use the blk_alloc_disk and blk_cleanup_disk
helpers to simplify gendisk and request_queue allocation.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Link: https://lore.kernel.org/r/20210521055116.1053587-21-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: store a block_device pointer in struct bio

Replace the gendisk pointer in struct bio with a pointer to the newly
improved struct block device. From that the gendisk can be trivially
accessed with an extra indirection, but it also allows to directly
look up all information related to partition remapping.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

xtensa/simdisk: remove the call to check_disk_change

The simdisk driver doesn't support event notifications, which means
that check_disk_change is a no-op.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: move ->make_request_fn to struct block_device_operations

The make_request_fn is a little weird in that it sits directly in
struct request_queue instead of an operation vector. Replace it with
a block_device_operations method called submit_bio (which describes much
better what it does). Also remove the request_queue argument to it, as
the queue can be derived pretty trivially from the bio.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

simdisk: stop using ->queuedata

Instead of setting up the queuedata as well just use one private data
field.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: simplify queue allocation

Current make_request based drivers use either blk_alloc_queue_node or
blk_alloc_queue to allocate a queue, and then set up the make_request_fn
function pointer and a few parameters using the blk_queue_make_request
helper. Simplify this by passing the make_request pointer to
blk_alloc_queue, and while at it merge the _node variant into the main
helper by always passing a node_id, and remove the superfluous gfp_mask
parameter. A lower-level __blk_alloc_queue is kept for the blk-mq case.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

proc: convert everything to "struct proc_ops"

The most notable change is DEFINE_SHOW_ATTRIBUTE macro split in
seq_file.h.

Conversion rule is:

llseek => proc_lseek
unlocked_ioctl => proc_ioctl

xxx => proc_xxx

delete ".owner = THIS_MODULE" line

[akpm@linux-foundation.org: fix drivers/isdn/capi/kcapi_proc.c]
[sfr@canb.auug.org.au: fix kernel/sched/psi.c]
Link: http://lkml.kernel.org/r/20200122180545.36222f50@canb.auug.org.au
Link: http://lkml.kernel.org/r/20191225172546.GB13378@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

xtensa: set proper error code for simdisk_setup()

Change error code to -ENOMEM from -EIO because
the error is related to memory allocating.

Signed-off-by: Chengguang Xu <cgxu519@gmail.com>
Message-Id: <1557066367-4783-2-git-send-email-cgxu519@gmail.com>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

xtensa: fix incorrect fd close in error case of simdisk_setup()

dev->fd is opened in attach operation, so should not
close dev->fd in error case of simdisk_setup().

Signed-off-by: Chengguang Xu <cgxu519@gmail.com>
Message-Id: <1557066367-4783-1-git-send-email-cgxu519@gmail.com>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

block: Move SECTOR_SIZE and SECTOR_SHIFT definitions into <linux/blkdev.h>

It happens often while I'm preparing a patch for a block driver that
I'm wondering: is a definition of SECTOR_SIZE and/or SECTOR_SHIFT
available for this driver? Do I have to introduce definitions of these
constants before I can use these constants? To avoid this confusion,
move the existing definitions of SECTOR_SIZE and SECTOR_SHIFT into the
<linux/blkdev.h> header file such that these become available for all
block drivers. Make the SECTOR_SIZE definition in the uapi msdos_fs.h
header file conditional to avoid that including that header file after
<linux/blkdev.h> causes the compiler to complain about a SECTOR_SIZE
redefinition.

Note: the SECTOR_SIZE / SECTOR_SHIFT / SECTOR_BITS definitions have
not been removed from uapi header files nor from NAND drivers in
which these constants are used for another purpose than converting
block layer offsets and sizes into a number of sectors.

Cc: David S. Miller <davem@davemloft.net>
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

xtensa/simdisk: fix compile error

Fixes: d004a5e7d4dd ("block: remove __bio_kmap_atomic")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: remove __bio_kmap_atomic

This helper doesn't buy us much over calling kmap_atomic directly.
In fact in the only caller it does a bit of useless work as the
caller already has the bvec at hand, and said caller would even
buggy for a multi-segment bio due to the use of this helper.

So just remove it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

xtensa: ISS: Use kmalloc_array() in simdisk_init()

* A multiplication for the size determination of a memory allocation
indicated that an array data structure should be processed.
Thus use the corresponding function "kmalloc_array".

This issue was detected by using the Coccinelle software.

* Replace the specification of a data type by a pointer dereference
to make the corresponding size determination a bit safer according to
the Linux coding style convention.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

Replace <asm/uaccess.h> with <linux/uaccess.h> globally

This was entirely automated, using the script by Al:

PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>'
sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \
$(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)

to do the replacement at the end of the merge window.

Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

xtensa: ISS: allow simdisk to use high memory buffers

ISS kernel by default has only low memory. But it may be configured to
support high memory and started in a simulator with more than 128M of
RAM. Simdisk driver in such configuration can get IO request with a
high memory page. There may be no TLB entry for that page, only page
table entry. However simulators don't do pagewalking, so such IO request
will fail. Touch IO buffer in the buffer read/write loop so that a TLB
entry is likely there when read or write simcall is invoked.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

convert a bunch of open-coded instances of memdup_user_nul()

A _lot_ of ->write() instances were open-coding it; some are
converted to memdup_user_nul(), a lot more remain...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

block: change ->make_request_fn() and users to return a queue cookie

No functional changes in this patch, but it prepares us for returning
a more useful cookie related to the IO that was queued up.

Signed-off-by: Jens Axboe <axboe@fb.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Acked-by: Keith Busch <keith.busch@intel.com>

block: add a bi_error field to struct bio

Currently we have two different ways to signal an I/O error on a BIO:

(1) by clearing the BIO_UPTODATE flag
(2) by returning a Linux errno value to the bi_end_io callback

The first one has the drawback of only communicating a single possible
error (-EIO), and the second one has the drawback of not beeing persistent
when bios are queued up, and are not passed along from child to parent
bio in the ever more popular chaining scenario. Having both mechanisms
available has the additional drawback of utterly confusing driver authors
and introducing bugs where various I/O submitters only deal with one of
them, and the others have to add boilerplate code to deal with both kinds
of error returns.

So add a new bi_error field to store an errno value directly in struct
bio and remove the existing mechanisms to clean all this up.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

xtensa: fixup simdisk driver to work with immutable bio_vecs

Geert reported:

arch/xtensa/platforms/iss/simdisk.c:108:23: error: 'struct bio' has no member named 'bi_sector'
arch/xtensa/platforms/iss/simdisk.c:110:2: error: incompatible types when assigning to type 'int' from type 'struct bvec_iter'
arch/xtensa/platforms/iss/simdisk.c:110:2: error: request for member 'bi_size' in something not a structure or union
arch/xtensa/platforms/iss/simdisk.c:110:2: error: request for member 'bi_idx' in something not a structure or union
arch/xtensa/platforms/iss/simdisk.c:110:2: error: request for member 'bi_size' in something not a structure or union
arch/xtensa/platforms/iss/simdisk.c:110:2: error: request for member 'bi_size' in something not a structure or union
arch/xtensa/platforms/iss/simdisk.c:110:2: error: request for member 'bi_idx' in something not a structure or union
arch/xtensa/platforms/iss/simdisk.c:110:2: error: request for member 'bi_bvec_done' in something not a structure or union
arch/xtensa/platforms/iss/simdisk.c:110:2: error: request for member 'bi_idx' in something not a structure or union
arch/xtensa/platforms/iss/simdisk.c:110:2: error: request for member 'bi_bvec_done' in something not a structure or union
arch/xtensa/platforms/iss/simdisk.c:110:2: error: request for member 'bi_idx' in something not a structure or union
arch/xtensa/platforms/iss/simdisk.c:110:2: error: request for member 'bi_bvec_done' in something not a structure or union
arch/xtensa/platforms/iss/simdisk.c:110:2: error: request for member 'bv_len' in something not a structure or union
arch/xtensa/platforms/iss/simdisk.c:111:18: error: request for member 'bi_idx' in something not a structure or union
arch/xtensa/platforms/iss/simdisk.c:111:18: error: request for member 'bi_size' in something not a structure or union
arch/xtensa/platforms/iss/simdisk.c:111:18: error: request for member 'bi_size' in something not a structure or union
arch/xtensa/platforms/iss/simdisk.c:111:18: error: request for member 'bi_idx' in something not a structure or union
arch/xtensa/platforms/iss/simdisk.c:111:18: error: request for member 'bi_bvec_done' in something not a structure or union
arch/xtensa/platforms/iss/simdisk.c:111:18: error: request for member 'bi_idx' in something not a structure or union
arch/xtensa/platforms/iss/simdisk.c:111:18: error: request for member 'bi_bvec_done' in something not a structure or union
arch/xtensa/platforms/iss/simdisk.c:111:18: error: request for member 'bi_idx' in something not a structure or union
arch/xtensa/platforms/iss/simdisk.c:111:18: error: request for member 'bi_bvec_done' in something not a structure or union
arch/xtensa/platforms/iss/simdisk.c:111:18: error: request for member 'bi_idx' in something not a structure or union
arch/xtensa/platforms/iss/simdisk.c:111:18: error: request for member 'bi_size' in something not a structure or union
arch/xtensa/platforms/iss/simdisk.c:111:18: error: request for member 'bi_size' in something not a structure or union
arch/xtensa/platforms/iss/simdisk.c:111:18: error: request for member 'bi_idx' in something not a structure or union
arch/xtensa/platforms/iss/simdisk.c:111:18: error: request for member 'bi_bvec_done' in something not a structure or union
arch/xtensa/platforms/iss/simdisk.c:111:18: error: request for member 'bi_idx' in something not a structure or union
arch/xtensa/platforms/iss/simdisk.c:111:18: error: request for member 'bi_bvec_done' in something not a structure or union
arch/xtensa/platforms/iss/simdisk.c:111:18: error: request for member 'bi_idx' in something not a structure or union
arch/xtensa/platforms/iss/simdisk.c:111:18: error: request for member 'bi_bvec_done' in something not a structure or union
make[2]: *** [arch/xtensa/platforms/iss/simdisk.o] Error 1

Fixup the usage of bio_for_each_segment(). Also fix wrong use
of __bio_kunmap_atomic() - it needs the mapped buffer passed in,
not the originally mapped page.

Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

xtensa: remove the second argument of __bio_kmap_atomic()

kmap_atomic allows only one argument now, just remove the unused 'kmtype'.

Signed-off-by: Zhao Hongjiang <zhaohongjiang@huawei.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Chris Zankel <chris@zankel.net>

xtensa simdisk: Fix proc_create_data() conversion fallout

arch/xtensa/platforms/iss/simdisk.c: In function 'proc_read_simdisk':
arch/xtensa/platforms/iss/simdisk.c:220:12: warning: initialization discards 'const' qualifier from pointer target type [enabled by default]
arch/xtensa/platforms/iss/simdisk.c: In function 'proc_write_simdisk':
arch/xtensa/platforms/iss/simdisk.c:241:38: error: 'buffer' undeclared (first use in this function)
arch/xtensa/platforms/iss/simdisk.c:241:38: note: each undeclared identifier is reported only once for each function it appears in

Introduced by commit a69755b187749e7cc020e17127a54f395aea4eaa ("xtensa
simdisk: switch to proc_create_data()")

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

xtensa: don't use a7 in simcalls

To support FRAME_POINTER avoid using a7 in __simc (none of the existing
simcalls needs it). Replace calls to __simc with more specific
simc_read, simc_write and simc_lseek calls.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>

block_device_operations->release() should return void

The value passed is 0 in all but "it can never happen" cases (and those
only in a couple of drivers) *and* it would've been lost on the way
out anyway, even if something tried to pass something meaningful.
Just don't bother.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

xtensa simdisk: fix braino in "xtensa simdisk: switch to proc_create_data()"

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

procfs: new helper - PDE_DATA(inode)

The only part of proc_dir_entry the code outside of fs/proc
really cares about is PDE(inode)->data. Provide a helper
for that; static inline for now, eventually will be moved
to fs/proc, along with the knowledge of struct proc_dir_entry
layout.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

xtensa simdisk: switch to proc_create_data()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

xtensa: ISS: add host file-based simulated disk

Simdisk is a block device that maps to a file in the host file system.
It is usable for testing in the simulated environment, like xt-sim or
QEMU. Device binding to host file may be changed at runtime via proc
interface provided the device is not in use. Number of block devices
and initial binding to host files is controlled via kernel/module
parameters, with defaults specified in the kernel configuration.

Signed-off-by: Victor Prupis <vnp@tensilica.com>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>