Add UBLK_F_SHMEM_ZC (1ULL << 19) to the UAPI header and UBLK_F_ALL.
Switch ublk_support_shmem_zc() and ublk_dev_support_shmem_zc() from
returning false to checking the actual flag, enabling the shared
memory zero-copy feature for devices that request it.
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://patch.msgid.link/20260331153207.3635125-4-ming.lei@redhat.com
[axboe: ublk_buf_reg -> ublk_shmem_buf_reg errors]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
There are no more callers of this function after commit f6b2d8b134
("btrfs: track the next file offset in struct btrfs_bio_ctrl"), so
remove the function.
Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Kanchan Joshi <joshi.k@samsung.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Add a blk_crypto_submit_bio helper that either submits the bio when
it is not encrypted or inline encryption is provided, but otherwise
handles the encryption before going down into the low-level driver.
This reduces the risk from bio reordering and keeps memory allocation
as high up in the stack as possible.
Note that if the submitter knows that inline enctryption is known to
be supported by the underyling driver, it can still use plain
submit_bio.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
A previous commit removed the use of this footnote, delete it.
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Fixes: 3fdf2ec7da ("Documentation: ublk: Drop Stefan Hajnoczi's message footnote")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Until this point, the kernel can use hardware-wrapped keys to do
encryption if userspace provides one -- specifically a key in
ephemerally-wrapped form. However, no generic way has been provided for
userspace to get such a key in the first place.
Getting such a key is a two-step process. First, the key needs to be
imported from a raw key or generated by the hardware, producing a key in
long-term wrapped form. This happens once in the whole lifetime of the
key. Second, the long-term wrapped key needs to be converted into
ephemerally-wrapped form. This happens each time the key is "unlocked".
In Android, these operations are supported in a generic way through
KeyMint, a userspace abstraction layer. However, that method is
Android-specific and can't be used on other Linux systems, may rely on
proprietary libraries, and also misleads people into supporting KeyMint
features like rollback resistance that make sense for other KeyMint keys
but don't make sense for hardware-wrapped inline encryption keys.
Therefore, this patch provides a generic kernel interface for these
operations by introducing new block device ioctls:
- BLKCRYPTOIMPORTKEY: convert a raw key to long-term wrapped form.
- BLKCRYPTOGENERATEKEY: have the hardware generate a new key, then
return it in long-term wrapped form.
- BLKCRYPTOPREPAREKEY: convert a key from long-term wrapped form to
ephemerally-wrapped form.
These ioctls are implemented using new operations in blk_crypto_ll_ops.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Tested-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org> # sm8650
Link: https://lore.kernel.org/r/20250204060041.409950-4-ebiggers@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
To prevent keys from being compromised if an attacker acquires read
access to kernel memory, some inline encryption hardware can accept keys
which are wrapped by a per-boot hardware-internal key. This avoids
needing to keep the raw keys in kernel memory, without limiting the
number of keys that can be used. Such hardware also supports deriving a
"software secret" for cryptographic tasks that can't be handled by
inline encryption; this is needed for fscrypt to work properly.
To support this hardware, allow struct blk_crypto_key to represent a
hardware-wrapped key as an alternative to a raw key, and make drivers
set flags in struct blk_crypto_profile to indicate which types of keys
they support. Also add the ->derive_sw_secret() low-level operation,
which drivers supporting wrapped keys must implement.
For more information, see the detailed documentation which this patch
adds to Documentation/block/inline-encryption.rst.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Tested-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org> # sm8650
Link: https://lore.kernel.org/r/20250204060041.409950-2-ebiggers@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Sphinx reports unreferenced footnote warning pointing to ubd-control
message by Stefan Hajnoczi:
Documentation/block/ublk.rst:336: WARNING: Footnote [#] is not referenced. [ref.footnote]
Drop the footnote to squash above warning.
Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
Fixes: 4093cb5a06 ("ublk_drv: add mechanism for supporting unprivileged ublk device")
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Link: https://lore.kernel.org/r/20250122143456.68867-3-bagasdotme@gmail.com
Move the cache control settings into the queue_limits so that the flags
can be set atomically with the device queue frozen.
Add new features and flags field for the driver set flags, and internal
(usually sysfs-controlled) flags in the block layer. Note that we'll
eventually remove enough field from queue_limits to bring it back to the
previous size.
The disable flag is inverted compared to the previous meaning, which
means it now survives a rescan, similar to the max_sectors and
max_discard_sectors user limits.
The FLUSH and FUA flags are now inherited by blk_stack_limits, which
simplified the code in dm a lot, but also causes a slight behavior
change in that dm-switch and dm-unstripe now advertise a write cache
despite setting num_flush_bios to 0. The I/O path will handle this
gracefully, but as far as I can tell the lack of num_flush_bios
and thus flush support is a pre-existing data integrity bug in those
targets that really needs fixing, after which a non-zero num_flush_bios
should be required in dm for targets that map to underlying devices.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Link: https://lore.kernel.org/r/20240617060532.127975-14-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Move the integrity information into the queue limits so that it can be
set atomically with other queue limits, and that the sysfs changes to
the read_verify and write_generate flags are properly synchronized.
This also allows to provide a more useful helper to stack the integrity
fields, although it still is separate from the main stacking function
as not all stackable devices want to inherit the integrity settings.
Even with that it greatly simplifies the code in md and dm.
Note that the integrity field is moved as-is into the queue limits.
While there are good arguments for removing the separate blk_integrity
structure, this would cause a lot of churn and might better be done at a
later time if desired. However the integrity field in the queue_limits
structure is now unconditional so that various ifdefs can be avoided or
replaced with IS_ENABLED(). Given that tiny size of it that seems like
a worthwhile trade off.
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/20240613084839.1044015-13-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Pull documentation updates from Jonathan Corbet:
"The number of commits for documentation is not huge this time around,
but there are some significant changes nonetheless:
- Some more Spanish-language and Chinese translations
- The much-discussed documentation of the confidential-computing
threat model
- Powerpc and RISCV documentation move under Documentation/arch -
these complete this particular bit of documentation churn
- A large traditional-Chinese documentation update
- A new document on backporting and conflict resolution
- Some kernel-doc and Sphinx fixes
Plus the usual smattering of smaller updates and typo fixes"
* tag 'docs-6.7' of git://git.lwn.net/linux: (40 commits)
scripts/kernel-doc: Fix the regex for matching -Werror flag
docs: backporting: address feedback
Documentation: driver-api: pps: Update PPS generator documentation
speakup: Document USB support
doc: blk-ioprio: Bring the doc in line with the implementation
docs: usb: fix reference to nonexistent file in UVC Gadget
docs: doc-guide: mention 'make refcheckdocs'
Documentation: fix typo in dynamic-debug howto
scripts/kernel-doc: match -Werror flag strictly
Documentation/sphinx: Remove the repeated word "the" in comments.
docs: sparse: add SPDX-License-Identifier
docs/zh_CN: Add subsystem-apis Chinese translation
docs/zh_TW: update contents for zh_TW
docs: submitting-patches: encourage direct notifications to commenters
docs: add backporting and conflict resolution document
docs: move riscv under arch
docs: update link to powerpc/vmemmap_dedup.rst
mm/memory-hotplug: fix typo in documentation
docs: move powerpc under arch
PCI: Update the devres documentation regarding to pcim_*()
...
Pull documentation updates from Jonathan Corbet:
"Documentation work keeps chugging along; this includes:
- Work from Carlos Bilbao to integrate rustdoc output into the
generated HTML documentation. This took some work to figure out how
to do it without slowing the docs build and without creating people
who don't have Rust installed, but Carlos got there
- Move the loongarch and mips architecture documentation under
Documentation/arch/
- Some more maintainer documentation from Jakub
... plus the usual assortment of updates, translations, and fixes"
* tag 'docs-6.6' of git://git.lwn.net/linux: (56 commits)
Docu: genericirq.rst: fix irq-example
input: docs: pxrc: remove reference to phoenix-sim
Documentation: serial-console: Fix literal block marker
docs/mm: remove references to hmm_mirror ops and clean typos
docs/zh_CN: correct regi_chg(),regi_add() to region_chg(),region_add()
Documentation: Fix typos
Documentation/ABI: Fix typos
scripts: kernel-doc: fix macro handling in enums
scripts: kernel-doc: parse DEFINE_DMA_UNMAP_[ADDR|LEN]
Documentation: riscv: Update boot image header since EFI stub is supported
Documentation: riscv: Add early boot document
Documentation: arm: Add bootargs to the table of added DT parameters
docs: kernel-parameters: Refer to the correct bitmap function
doc: update params of memhp_default_state=
docs: Add book to process/kernel-docs.rst
docs: sparse: fix invalid link addresses
docs: vfs: clean up after the iterate() removal
docs: Add a section on surveys to the researcher guidelines
docs: move mips under arch
docs: move loongarch under arch
...