Use the same values for use for request completion errors as the return
value from ->queue_rq. BLK_STS_RESOURCE is special cased to cause
a requeue, and all the others are completed as-is.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
Currently we use nornal Linux errno values in the block layer, and while
we accept any error a few have overloaded magic meanings. This patch
instead introduces a new blk_status_t value that holds block layer specific
status codes and explicitly explains their meaning. Helpers to convert from
and to the previous special meanings are provided for now, but I suspect
we want to get rid of them in the long run - those drivers that have a
errno input (e.g. networking) usually get errnos that don't know about
the special block layer overloads, and similarly returning them to userspace
will usually return somethings that strictly speaking isn't correct
for file system operations, but that's left as an exercise for later.
For now the set of errors is a very limited set that closely corresponds
to the previous overloaded errno values, but there is some low hanging
fruite to improve it.
blk_status_t (ab)uses the sparse __bitwise annotations to allow for sparse
typechecking, so that we can easily catch places passing the wrong values.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
Remove the request_idx parameter, which can't be used safely now that we
support I/O schedulers with blk-mq. Except for a superflous check in
mtip32xx it was unused anyway.
Also pass the tag_set instead of just the driver data - this allows drivers
to avoid some code duplication in a follow on cleanup.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
Constify all instances of blk_mq_ops, as they are never modified.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Instead of keeping two levels of indirection for requests types, fold it
all into the operations. The little caveat here is that previously
cmd_type only applied to struct request, while the request and bio op
fields were set to plain REQ_OP_READ/WRITE even for passthrough
operations.
Instead this patch adds new REQ_OP_* for SCSI passthrough and driver
private requests, althought it has to add two for each so that we
can communicate the data in/out nature of the request.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
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>
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.
Cheers,
Rusty.
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Merge tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux
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 2d4dc890b5
("block: add helpers to run flush_dcache_page() against a bio and a
request's pages").
Fixes: 9d54c8a33e ("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: ff1f48ee3b ('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>
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>
Static volumes can change its 'used_bytes' when they get updated,
and so the block interface must listen to the UBI_VOLUME_UPDATED
notification to resize the block device accordingly.
Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Cc: stable@vger.kernel.org # v3.15+
We are currently taking the block device size from the ubi_volume_info.size
field. However, this is not the amount of data in the volume, but the
number of reserved physical eraseblocks, and hence leads to an incorrect
representation of the volume.
In particular, this produces I/O errors on static volumes as the block
interface may attempt to read unmapped PEBs:
$ cat /dev/ubiblock0_0 > /dev/null
UBI error: ubiblock_read_to_buf: ubiblock0_0 ubi_read error -22
end_request: I/O error, dev ubiblock0_0, sector 9536
Buffer I/O error on device ubiblock0_0, logical block 2384
[snip]
Fix this by using the ubi_volume_info.used_bytes field which is set to the
actual number of data bytes for both static and dynamic volumes.
While here, improve the error message to be less stupid and more useful:
UBI error: ubiblock_read_to_buf: ubiblock0_1 ubi_read error -9 on LEB=0, off=15872, len=512
It's worth noticing that the 512-byte sector representation of the volume
is only correct if the volume size is multiple of 512-bytes. This is true for
virtually any NAND device, given eraseblocks and pages are 512-byte multiple
and hence so is the LEB size.
Artem: tweak the error message and make it look more like other UBI error
messages.
Fixes: 9d54c8a33e ("UBI: R/O block driver on top of UBI volumes")
Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Cc: stable@vger.kernel.org # v3.15+
commit 4df38926f3 ("UBI: block: Avoid disk size integer overflow")
introduced a dereference on dev (which is not initialized at that
point) when printing a warning message. Re-order disk_capacity check
after the dev is found.
Found by cppcheck:
[drivers/mtd/ubi/block.c:509]: (error) Uninitialized variable: dev
Artem: tweak the error message a bit
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
This patch fixes the issue that on very large UBI volumes
UBI block does not work correctly.
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
There's no need to set the disk capacity with the mutex held, so this
commit takes the variable setting out of the mutex. This simplifies
the disk capacity fix for very large volumes in a follow up commit.
Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Currently, ubiblock_resize() can fail if the device is not found
in the list. This commit changes the return type, so the function can
return something meaningful on error paths.
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
condition between the mmap page fault path and fsync. Another just removes a
bogus assertion from the UBIFS memory shrinker.
UBIFS also started honoring the MS_SILENT mount flag, so now it won't print
many I/O errors when user-space just tries to probe for the FS.
Rest of the changes are rather minor UBI/UBIFS fixes, improvements, and
clean-ups.
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Merge tag 'upstream-3.16-rc1-v2' of git://git.infradead.org/linux-ubifs
Pull UBIFS updates from Artem Bityutskiy:
"This contains several UBIFS fixes. One of them fixes a race condition
between the mmap page fault path and fsync. Another just removes a
bogus assertion from the UBIFS memory shrinker.
UBIFS also started honoring the MS_SILENT mount flag, so now it won't
print many I/O errors when user-space just tries to probe for the FS.
Rest of the changes are rather minor UBI/UBIFS fixes, improvements,
and clean-ups"
* tag 'upstream-3.16-rc1-v2' of git://git.infradead.org/linux-ubifs:
UBIFS: Add an assertion for clean_zn_cnt
UBIFS: respect MS_SILENT mount flag
UBIFS: Remove incorrect assertion in shrink_tnc()
UBIFS: fix debugging check
UBIFS: add missing ui pointer in debugging code
UBI: block: Fix error path on alloc_workqueue failure
UBIFS: Fix dump messages in ubifs_dump_lprops
UBI: fix rb_tree node comparison in add_map
UBIFS: Remove unused variables in ubifs_budget_space
UBI: weaken the 'exclusive' constraint when opening volumes to rename
UBIFS: fix an mmap and fsync race condition
Pull block core updates from Jens Axboe:
"It's a big(ish) round this time, lots of development effort has gone
into blk-mq in the last 3 months. Generally we're heading to where
3.16 will be a feature complete and performant blk-mq. scsi-mq is
progressing nicely and will hopefully be in 3.17. A nvme port is in
progress, and the Micron pci-e flash driver, mtip32xx, is converted
and will be sent in with the driver pull request for 3.16.
This pull request contains:
- Lots of prep and support patches for scsi-mq have been integrated.
All from Christoph.
- API and code cleanups for blk-mq from Christoph.
- Lots of good corner case and error handling cleanup fixes for
blk-mq from Ming Lei.
- A flew of blk-mq updates from me:
* Provide strict mappings so that the driver can rely on the CPU
to queue mapping. This enables optimizations in the driver.
* Provided a bitmap tagging instead of percpu_ida, which never
really worked well for blk-mq. percpu_ida relies on the fact
that we have a lot more tags available than we really need, it
fails miserably for cases where we exhaust (or are close to
exhausting) the tag space.
* Provide sane support for shared tag maps, as utilized by scsi-mq
* Various fixes for IO timeouts.
* API cleanups, and lots of perf tweaks and optimizations.
- Remove 'buffer' from struct request. This is ancient code, from
when requests were always virtually mapped. Kill it, to reclaim
some space in struct request. From me.
- Remove 'magic' from blk_plug. Since we store these on the stack
and since we've never caught any actual bugs with this, lets just
get rid of it. From me.
- Only call part_in_flight() once for IO completion, as includes two
atomic reads. Hopefully we'll get a better implementation soon, as
the part IO stats are now one of the more expensive parts of doing
IO on blk-mq. From me.
- File migration of block code from {mm,fs}/ to block/. This
includes bio.c, bio-integrity.c, bounce.c, and ioprio.c. From me,
from a discussion on lkml.
That should describe the meat of the pull request. Also has various
little fixes and cleanups from Dave Jones, Shaohua Li, Duan Jiong,
Fengguang Wu, Fabian Frederick, Randy Dunlap, Robert Elliott, and Sam
Bradshaw"
* 'for-3.16/core' of git://git.kernel.dk/linux-block: (100 commits)
blk-mq: push IPI or local end_io decision to __blk_mq_complete_request()
blk-mq: remember to start timeout handler for direct queue
block: ensure that the timer is always added
blk-mq: blk_mq_unregister_hctx() can be static
blk-mq: make the sysfs mq/ layout reflect current mappings
blk-mq: blk_mq_tag_to_rq should handle flush request
block: remove dead code in scsi_ioctl:blk_verify_command
blk-mq: request initialization optimizations
block: add queue flag for disabling SG merging
block: remove 'magic' from struct blk_plug
blk-mq: remove alloc_hctx and free_hctx methods
blk-mq: add file comments and update copyright notices
blk-mq: remove blk_mq_alloc_request_pinned
blk-mq: do not use blk_mq_alloc_request_pinned in blk_mq_map_request
blk-mq: remove blk_mq_wait_for_tags
blk-mq: initialize request in __blk_mq_alloc_request
blk-mq: merge blk_mq_alloc_reserved_request into blk_mq_alloc_request
blk-mq: add helper to insert requests from irq context
blk-mq: remove stale comment for blk_mq_complete_request()
blk-mq: allow non-softirq completions
...
Otherwise we'd return a random value if allocation of the workqueue fails.
Signed-off-by: Helmut Schaa <helmut.schaa@googlemail.com>
Acked-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
When building the name for the workqueue thread, make sure a format
string cannot leak in from the disk name.
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
This was used in the olden days, back when onions were proper
yellow. Basically it mapped to the current buffer to be
transferred. With highmem being added more than a decade ago,
most drivers map pages out of a bio, and rq->buffer isn't
pointing at anything valid.
Convert old style drivers to just use bio_data().
For the discard payload use case, just reference the page
in the bio.
Signed-off-by: Jens Axboe <axboe@fb.com>
You cannot mark these parameters as __initdata.
Otherwise the data is gone upon module exit.
Fixes:
[ 172.045465] BUG: unable to handle kernel paging request at ffffffffa001db38
[ 172.046020] IP: [<ffffffff81067aa4>] destroy_params+0x24/0x50
Signed-off-by: Richard Weinberger <richard@nod.at>
Acked-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Rename the UBI_IOCVOLATTBLK and UBI_IOCVOLDETBLK to UBI_IOCVOLCRBLK and
UBI_IOCVOLRMBLK, because we do not use terms "attach" and "detach" for the R/O
block devices on top of UBI volumes. Instead, we use terms "create" and
"remove". This patch also amends the related commentaries.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Acked-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Fixes the following warning on ARCH=avr32:
drivers/mtd/ubi/block.c: In function 'ubiblock_read':
drivers/mtd/ubi/block.c:207: warning: comparison of distinct pointer types lacks a cast
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
ubiblock_param_ops should be marked as __init as it's only used to set
a driver parameter on insertion time. This commit fixes the following:
WARNING: drivers/mtd/built-in.o(.text+0x653ac): Section mismatch in
reference from the variable ubiblock_param_ops to the function
.init.text:ubiblock_set_param()
The function ubiblock_param_ops() references the function __init
ubiblock_set_param(). This is often because ubiblock_param_ops lacks a
__init annotation or the annotation of ubiblock_set_param is wrong.
Given gcc errors if the struct is marked const __initdata, this commit
drops the const mark from it.
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
We already use term attach/detach for UBI->MTD relations, let's not use this
for UBI->ubiblock relations to avoid confusion. Just use 'create' and 'remove'
instead. E.g., "create a R/O block device on top of a UBI volume".
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
This commit introduces read-only block device emulation on top of UBI volumes.
Given UBI takes care of wear leveling and bad block management it's possible
to add a thin layer to enable block device access to UBI volumes.
This allows to use a block-oriented filesystem on a flash device.
The UBI block devices are meant to be used in conjunction with any
regular, block-oriented file system (e.g. ext4), although it's primarily
targeted at read-only file systems, such as squashfs.
Block devices are created upon user request through new ioctls:
UBI_IOCVOLATTBLK to attach and UBI_IOCVOLDETBLK to detach.
Also, a new UBI module parameter is added 'ubi.block'. This parameter is
needed in order to attach a block device on boot-up time, allowing to
mount the rootfs on a ubiblock device.
For instance, you could have these kernel parameters:
ubi.mtd=5 ubi.block=0,0 root=/dev/ubiblock0_0
Or, if you compile ubi as a module:
$ modprobe ubi mtd=/dev/mtd5 block=/dev/ubi0_0
Artem: amend commentaries and massage the patch a little bit.
Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Christoph Hellwig