All drivers use the default, so provide an inline version of it.  If we
ever need other queue mapping we can add an optional method back,
although supporting will also require major changes to the queue setup
code.

This provides better code generation, and better debugability as well.

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

Pull module updates from Rusty Russell:
 "Main excitement here is Peter Zijlstra's lockless rbtree optimization
  to speed module address lookup.  He found some abusers of the module
  lock doing that too.

  A little bit of parameter work here too; including Dan Streetman's
  breaking up the big param mutex so writing a parameter can load
  another module (yeah, really).  Unfortunately that broke the usual
  suspects, !CONFIG_MODULES and !CONFIG_SYSFS, so those fixes were
  appended too"

* tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: (26 commits)
  modules: only use mod->param_lock if CONFIG_MODULES
  param: fix module param locks when !CONFIG_SYSFS.
  rcu: merge fix for Convert ACCESS_ONCE() to READ_ONCE() and WRITE_ONCE()
  module: add per-module param_lock
  module: make perm const
  params: suppress unused variable error, warn once just in case code changes.
  modules: clarify CONFIG_MODULE_COMPRESS help, suggest 'N'.
  kernel/module.c: avoid ifdefs for sig_enforce declaration
  kernel/workqueue.c: remove ifdefs over wq_power_efficient
  kernel/params.c: export param_ops_bool_enable_only
  kernel/params.c: generalize bool_enable_only
  kernel/module.c: use generic module param operaters for sig_enforce
  kernel/params: constify struct kernel_param_ops uses
  sysfs: tightened sysfs permission checks
  module: Rework module_addr_{min,max}
  module: Use __module_address() for module_address_lookup()
  module: Make the mod_tree stuff conditional on PERF_EVENTS || TRACING
  module: Optimize __module_address() using a latched RB-tree
  rbtree: Implement generic latch_tree
  seqlock: Introduce raw_read_seqcount_latch()
  ...

This patch makes ubiblock devices have minor numbers beginning from
0, allocated dynamically independently of the ubi device/volume
number. This property becomes useful because, on 32-bit architectures
with LFS turned off in a userspace program, device minor numbers
over 8 bits cause stat to return -EOVERFLOW. If the device number is
high (>1) due to multiple MTD partitions, such an overflow will occur.
While enabling LFS is clearly a nicer solution, it's often difficult
to turn on in practice globally as many widely distributed packages
don't work with LFS on.

Other storage systems have their own workarounds, with SCSI making
multiple device majors and MMC having a config option for the number
of partitions per device. A completely dynamic minor numbering is
simpler than these. It is unlikely that anyone is depending on a
static minor number since the major is dynamic anyway. In addition,
ubiblock is still relatively new, so now is the time to make such
changes.

Signed-off-by: Dan Ehrenberg <dehrenberg@chromium.org>
Acked-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Signed-off-by: Richard Weinberger <richard@nod.at>

Most code already uses consts for the struct kernel_param_ops,
sweep the kernel for the last offending stragglers. Other than
include/linux/moduleparam.h and kernel/params.c all other changes
were generated with the following Coccinelle SmPL patch. Merge
conflicts between trees can be handled with Coccinelle.

In the future git could get Coccinelle merge support to deal with
patch --> fail --> grammar --> Coccinelle --> new patch conflicts
automatically for us on patches where the grammar is available and
the patch is of high confidence. Consider this a feature request.

Test compiled on x86_64 against:

	* allnoconfig
	* allmodconfig
	* allyesconfig

@ const_found @
identifier ops;
@@

const struct kernel_param_ops ops = {
};

@ const_not_found depends on !const_found @
identifier ops;
@@

-struct kernel_param_ops ops = {
+const struct kernel_param_ops ops = {
};

Generated-by: Coccinelle SmPL
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Junio C Hamano <gitster@pobox.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: cocci@systeme.lip6.fr
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Luis R. Rodriguez <mcgrof@suse.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

Block drivers are responsible for calling flush_dcache_page() on each
BIO request. This operation keeps the I$ coherent with the D$ on
architectures that don't have hardware coherency support. Without this
flush, random crashes are seen when executing user programs from an ext4
filesystem backed by a ubiblock device.

This patch is based on the change implemented in commit 2d4dc890b5c8
("block: add helpers to run flush_dcache_page() against a bio and a
request's pages").

Fixes: 9d54c8a33eec ("UBI: R/O block driver on top of UBI volumes")
Signed-off-by: Kevin Cernekee <cernekee@chromium.org>
Signed-off-by: Ezequiel Garcia <ezequiel.garcia@imgtec.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

We recently switched from allocating ->rq using blk_init_queue() to
use blk_mq_init_queue() so we need to update the error handling to
check for IS_ERR() instead of NULL.

Fixes: ff1f48ee3bb3 ('UBI: Block: Add blk-mq support')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

If one ubi volume is corrupted but another is not, it should be
possible to initialize that ubiblock from a kernel commandline which
includes both of them. This patch changes the error handling behavior
in initializing ubiblock to ensure that all parameters are attempted
even if one fails. If there is a failure, it is logged on dmesg.
It also makes error messages more descriptive by including the
name of the UBI volume that failed.

Tested: Formatted ubi volume /dev/ubi5_0 in a corrupt way and
dev/ubi3_0 properly and included "ubi.block=5,0 ubi.block=3,0" on
the kernel command line. At boot, I see the following in the console:
[   21.082420] UBI error: ubiblock_create_from_param: block: can't open volume on ubi5_0, err=-19
[   21.084268] UBI: ubiblock3_0 created from ubi3:0(rootfs)

Signed-off-by: Dan Ehrenberg <dehrenberg@chromium.org>
Reviewed-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Signed-off-by: Richard Weinberger <richard@nod.at>

Signed-off-by: Richard Weinberger <richard@nod.at>

Convert the driver to blk-mq.
Beside of moving to the modern block interface this change boosts
also the performance of the driver.

nand: device found, Manufacturer ID: 0x2c, Chip ID: 0xda
nand: Micron NAND 256MiB 3,3V 8-bit
nand: 256MiB, SLC, page size: 2048, OOB size: 64

root@debian-armhf:~# dd if=/dev/ubiblock0_0 of=/dev/zero bs=1M
243+1 records in
243+1 records out
255080448 bytes (255 MB) copied, 4.39295 s, 58.1 MB/s

vs.

root@debian-armhf:~# dd if=/dev/ubiblock0_0 of=/dev/zero bs=1M
243+1 records in
243+1 records out
255080448 bytes (255 MB) copied, 2.87676 s, 88.7 MB/s

Cc: hch@infradead.org
Cc: axboe@fb.com
Cc: tom.leiming@gmail.com
Signed-off-by: Richard Weinberger <richard@nod.at>
Tested-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Reviewed-by: Jens Axboe <axboe@fb.com>
Acked-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>

If there is more then one UBI device mounted, there is no way to
distinguish between messages from different UBI devices.
Add device number to all ubi layer message types.

The R/O block driver messages were replaced by pr_* since
ubi_device structure is not used by it.

Amended a bit by Artem.

Signed-off-by: Tanya Brokhman <tlinder@codeaurora.org>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>