add patch lk6.7-rc1-v2

patches/lk6.7-rc1-v2/v6-0000-cover-letter.patch

@@ -0,0 +1,209 @@
+From e6e7a6261134ca91bd4768a70ecc7dd31c2388e1 Mon Sep 17 00:00:00 2001
+From: Sergei Shtepa <[email protected]>
+Date: Thu, 16 Nov 2023 12:32:58 +0100
+Subject: [PATCH v6 00/11] blksnap - block devices snapshots module
+
+Hi all.
+
+I am happy to offer a improved version of the Block Devices Snapshots
+Module. It allows to create non-persistent snapshots of any block devices.
+The main purpose of such snapshots is to provide backups of block devices.
+See more in Documentation/block/blksnap.rst.
+
+The Block Device Filtering Mechanism is added to the block layer. This
+allows to attach and detach block device filters to the block layer.
+Filters allow to extend the functionality of the block layer.
+See more in Documentation/block/blkfilter.rst.
+
+The tool, library and tests for working with blksnap can be found on github.
+Link: https://github.com/veeam/blksnap/tree/stable-v2.0
+
+In the new version, the method of saving shapshot difference has been
+changed. Why this should have been done, Dave Chinner <[email protected]>
+described in detail in the comments to the previous version.
+Link: https://lore.kernel.org/lkml/[email protected]/T/#mfe9b8f46833011deea4b24714212230ac38db978
+
+The module is incompatible with features hardware inline encryption and
+data integrity.
+Link: https://lore.kernel.org/lkml/[email protected]/T/#m3f13e580876bff1d283eb2a79d1ecdef3b98cc42
+
+Based on LK v6.7-rc1.
+
+v6 changes:
+- The difference storage has been changed.
+  In the previous version, the file was created only to reserve sector
+  ranges on a block device. The data was stored directly to the block
+  device in these sector ranges. Now saving and reading data is done using
+  'VFS' using vfs_iter_write() and vfs_iter_read() functions. This allows
+  not to depend on the filesystem and use, for example, tmpfs. Using an
+  unnamed temporary file allows to hide it from other processes and
+  automatically release it when the snapshot is closed.
+  However, now the module does not allow to add a block device to the
+  snapshot on which the difference stoarge is located. There is no way to
+  ensure the immutability of file metadata when writing data to a file.
+  This means that the metadata of the filesystem may change, which may
+  cause damage to the snapshot.
+- _IOW and _IOR were mixed up - fixed. 
+- Protection against the use of the snapshots for block devices with
+  hardware inline encryption and data integrity was implemented.
+  Compatibility with them was not planned and has not been tested at the
+  moment.
+
+v5 changes:
+- Rebase for "kernel/git/axboe/linux-block.git" branch "for-6.5/block".
+  Link: https://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux-block.git/log/?h=for-6.5/block
+
+v4 changes:
+- Structures for describing the state of chunks are allocated dynamically.
+  This reduces memory consumption, since the struct chunk is allocated only
+  for those blocks for which the snapshot image state differs from the
+  original block device.
+- The algorithm for calculating the chunk size depending on the size of the
+  block device has been changed. For large block devices, it is now
+  possible to allocate a larger number of chunks, and their size is smaller.
+- For block devices, a 'filter' file has been added to /sys/block/<device>.
+  It displays the name of the filter that is attached to the block device.
+- Fixed a problem with the lack of protection against re-adding a block
+  device to a snapshot.
+- Fixed a bug in the algorithm of allocating the next bio for a chunk.
+  This problem was accurred on large disks, for which a chunk consists of
+  at least two bio.
+- The ownership mechanism of the diff_area structure has been changed.
+  This fixed the error of prematurely releasing the diff_area structure
+  when destroying the snapshot.
+- Documentation corrected.
+- The Sparse analyzer is passed.
+- Use __u64 type instead pointers in UAPI.
+
+v3 changes:
+- New block device I/O controls BLKFILTER_ATTACH and BLKFILTER_DETACH allow
+  to attach and detach filters.
+- New block device I/O control BLKFILTER_CTL allow send command to attached
+  block device filter.
+- The copy-on-write algorithm for processing I/O units has been optimized
+  and has become asynchronous.
+- The snapshot image reading algorithm has been optimized and has become
+  asynchronous.
+- Optimized the finite state machine for processing chunks.
+- Fixed a tracking block size calculation bug.
+
+v2 changes:
+- Added documentation for Block Device Filtering Mechanism.
+- Added documentation for Block Devices Snapshots Module (blksnap).
+- The MAINTAINERS file has been updated.
+- Optimized queue code for snapshot images.
+- Fixed comments, log messages and code for better readability.
+
+v1 changes:
+- Forgotten "static" declarations have been added.
+- The text of the comments has been corrected.
+- It is possible to connect only one filter, since there are no others in
+  upstream.
+- Do not have additional locks for attach/detach filter.
+- blksnap.h moved to include/uapi/.
+- #pragma once and commented code removed.
+- uuid_t removed from user API.
+- Removed default values for module parameters from the configuration file.
+- The debugging code for tracking memory leaks has been removed.
+- Simplified Makefile.
+- Optimized work with large memory buffers, CBT tables are now in virtual
+  memory.
+- The allocation code of minor numbers has been optimized.
+- The implementation of the snapshot image block device has been
+  simplified, now it is a bio-based block device.
+- Removed initialization of global variables with null values.
+- only one bio is used to copy one chunk.
+- Checked on ppc64le.
+
+
+Sergei Shtepa (11):
+  documentation: Block Device Filtering Mechanism
+  block: Block Device Filtering Mechanism
+  documentation: Block Devices Snapshots Module
+  blksnap: header file of the module interface
+  blksnap: module management interface functions
+  blksnap: handling and tracking I/O units
+  blksnap: difference storage and chunk
+  blksnap: event queue from the difference storage
+  blksnap: snapshot and snapshot image block device
+  blksnap: Kconfig and Makefile
+  blksnap: prevents using devices with data integrity or inline
+    encryption
+
+ Documentation/block/blkfilter.rst             |  66 ++
+ Documentation/block/blksnap.rst               | 352 +++++++++
+ Documentation/block/index.rst                 |   2 +
+ .../userspace-api/ioctl/ioctl-number.rst      |   1 +
+ MAINTAINERS                                   |  17 +
+ block/Makefile                                |   3 +-
+ block/bdev.c                                  |   2 +
+ block/blk-core.c                              |  35 +-
+ block/blk-filter.c                            | 238 +++++++
+ block/blk.h                                   |  11 +
+ block/genhd.c                                 |  10 +
+ block/ioctl.c                                 |   7 +
+ block/partitions/core.c                       |   9 +
+ drivers/block/Kconfig                         |   2 +
+ drivers/block/Makefile                        |   2 +
+ drivers/block/blksnap/Kconfig                 |  31 +
+ drivers/block/blksnap/Makefile                |  15 +
+ drivers/block/blksnap/cbt_map.c               | 228 ++++++
+ drivers/block/blksnap/cbt_map.h               |  90 +++
+ drivers/block/blksnap/chunk.c                 | 667 ++++++++++++++++++
+ drivers/block/blksnap/chunk.h                 | 142 ++++
+ drivers/block/blksnap/diff_area.c             | 601 ++++++++++++++++
+ drivers/block/blksnap/diff_area.h             | 175 +++++
+ drivers/block/blksnap/diff_buffer.c           | 115 +++
+ drivers/block/blksnap/diff_buffer.h           |  37 +
+ drivers/block/blksnap/diff_storage.c          | 291 ++++++++
+ drivers/block/blksnap/diff_storage.h          | 104 +++
+ drivers/block/blksnap/event_queue.c           |  81 +++
+ drivers/block/blksnap/event_queue.h           |  64 ++
+ drivers/block/blksnap/main.c                  | 475 +++++++++++++
+ drivers/block/blksnap/params.h                |  16 +
+ drivers/block/blksnap/snapimage.c             | 134 ++++
+ drivers/block/blksnap/snapimage.h             |  10 +
+ drivers/block/blksnap/snapshot.c              | 457 ++++++++++++
+ drivers/block/blksnap/snapshot.h              |  64 ++
+ drivers/block/blksnap/tracker.c               | 358 ++++++++++
+ drivers/block/blksnap/tracker.h               |  78 ++
+ include/linux/blk-filter.h                    |  51 ++
+ include/linux/blk_types.h                     |   1 +
+ include/linux/blkdev.h                        |   1 +
+ include/linux/sched.h                         |   1 +
+ include/uapi/linux/blk-filter.h               |  35 +
+ include/uapi/linux/blksnap.h                  | 388 ++++++++++
+ include/uapi/linux/fs.h                       |   3 +
+ 44 files changed, 5468 insertions(+), 2 deletions(-)
+ create mode 100644 Documentation/block/blkfilter.rst
+ create mode 100644 Documentation/block/blksnap.rst
+ create mode 100644 block/blk-filter.c
+ create mode 100644 drivers/block/blksnap/Kconfig
+ create mode 100644 drivers/block/blksnap/Makefile
+ create mode 100644 drivers/block/blksnap/cbt_map.c
+ create mode 100644 drivers/block/blksnap/cbt_map.h
+ create mode 100644 drivers/block/blksnap/chunk.c
+ create mode 100644 drivers/block/blksnap/chunk.h
+ create mode 100644 drivers/block/blksnap/diff_area.c
+ create mode 100644 drivers/block/blksnap/diff_area.h
+ create mode 100644 drivers/block/blksnap/diff_buffer.c
+ create mode 100644 drivers/block/blksnap/diff_buffer.h
+ create mode 100644 drivers/block/blksnap/diff_storage.c
+ create mode 100644 drivers/block/blksnap/diff_storage.h
+ create mode 100644 drivers/block/blksnap/event_queue.c
+ create mode 100644 drivers/block/blksnap/event_queue.h
+ create mode 100644 drivers/block/blksnap/main.c
+ create mode 100644 drivers/block/blksnap/params.h
+ create mode 100644 drivers/block/blksnap/snapimage.c
+ create mode 100644 drivers/block/blksnap/snapimage.h
+ create mode 100644 drivers/block/blksnap/snapshot.c
+ create mode 100644 drivers/block/blksnap/snapshot.h
+ create mode 100644 drivers/block/blksnap/tracker.c
+ create mode 100644 drivers/block/blksnap/tracker.h
+ create mode 100644 include/linux/blk-filter.h
+ create mode 100644 include/uapi/linux/blk-filter.h
+ create mode 100644 include/uapi/linux/blksnap.h
+
+-- 
+2.20.1
+

patches/lk6.7-rc1-v2/v6-0001-documentation-Block-Device-Filtering-Mechanism.patch

@@ -0,0 +1,124 @@
+From 879784a77d7f15d7b485be91199771ce525380a0 Mon Sep 17 00:00:00 2001
+From: Sergei Shtepa <[email protected]>
+Date: Tue, 7 Nov 2023 11:20:24 +0100
+Subject: [PATCH v6 01/11] documentation: Block Device Filtering Mechanism
+
+The document contains:
+* Describes the purpose of the mechanism
+* A little historical background on the capabilities of handling I/O
+  units of the Linux kernel
+* Brief description of the design
+* Reference to interface description
+
+Signed-off-by: Sergei Shtepa <[email protected]>
+---
+ Documentation/block/blkfilter.rst | 66 +++++++++++++++++++++++++++++++
+ Documentation/block/index.rst     |  1 +
+ MAINTAINERS                       |  6 +++
+ 3 files changed, 73 insertions(+)
+ create mode 100644 Documentation/block/blkfilter.rst
+
+diff --git a/Documentation/block/blkfilter.rst b/Documentation/block/blkfilter.rst
+new file mode 100644
+index 000000000000..4e148e78f3d4
+--- /dev/null
++++ b/Documentation/block/blkfilter.rst
+@@ -0,0 +1,66 @@
++.. SPDX-License-Identifier: GPL-2.0
++
++================================
++Block Device Filtering Mechanism
++================================
++
++The block device filtering mechanism provides the ability to attach block
++device filters. Block device filters allow performing additional processing
++for I/O units.
++
++Introduction
++============
++
++The idea of handling I/O units on block devices is not new. Back in the
++2.6 kernel, there was an undocumented possibility of handling I/O units
++by substituting the make_request_fn() function, which belonged to the
++request_queue structure. But none of the in-tree kernel modules used this
++feature, and it was eliminated in the 5.10 kernel.
++
++The block device filtering mechanism returns the ability to handle I/O units.
++It is possible to safely attach a filter to a block device "on the fly" without
++changing the structure of the block device's stack.
++
++It supports attaching one filter to one block device, because there is only
++one filter implementation in the kernel yet.
++See Documentation/block/blksnap.rst.
++
++Design
++======
++
++The block device filtering mechanism provides registration and unregistration
++for filter operations. The struct blkfilter_operations contains a pointer to
++the callback functions for the filter. After registering the filter operations,
++the filter can be managed using block device ioctls BLKFILTER_ATTACH,
++BLKFILTER_DETACH and BLKFILTER_CTL.
++
++When the filter is attached, the callback function is called for each I/O unit
++for a block device, providing I/O unit filtering. Depending on the result of
++filtering the I/O unit, it can either be passed for subsequent processing by
++the block layer, or skipped.
++
++The filter can be implemented as a loadable module. In this case, the filter
++module cannot be unloaded while the filter is attached to at least one of the
++block devices.
++
++Interface description
++=====================
++
++The ioctl BLKFILTER_ATTACH allows user-space programs to attach a block device
++filter to a block device. The ioctl BLKFILTER_DETACH allows user-space programs
++to detach it. Both ioctls use &struct blkfilter_name. The ioctl BLKFILTER_CTL
++allows user-space programs to send a filter-specific command. It use &struct
++blkfilter_ctl.
++
++.. kernel-doc:: include/uapi/linux/blk-filter.h
++
++To register in the system, the filter uses the &struct blkfilter_operations,
++which contains callback functions, unique filter name and module owner. When
++attaching a filter to a block device, the filter creates a &struct blkfilter.
++The pointer to the &struct blkfilter allows the filter to determine for which
++block device the callback functions are being called.
++
++.. kernel-doc:: include/linux/blk-filter.h
++
++.. kernel-doc:: block/blk-filter.c
++   :export:
+diff --git a/Documentation/block/index.rst b/Documentation/block/index.rst
+index 9fea696f9daa..e9712f72cd6d 100644
+--- a/Documentation/block/index.rst
++++ b/Documentation/block/index.rst
+@@ -10,6 +10,7 @@ Block
+    bfq-iosched
+    biovecs
+    blk-mq
++   blkfilter
+    cmdline-partition
+    data-integrity
+    deadline-iosched
+diff --git a/MAINTAINERS b/MAINTAINERS
+index 97f51d5ec1cf..c20cbec81b58 100644
+--- a/MAINTAINERS
++++ b/MAINTAINERS
+@@ -3584,6 +3584,12 @@ M:	Jan-Simon Moeller <[email protected]>
+ S:	Maintained
+ F:	drivers/leds/leds-blinkm.c
+
++BLOCK DEVICE FILTERING MECHANISM
++M:	Sergei Shtepa <[email protected]>
++L:	[email protected]
++S:	Supported
++F:	Documentation/block/blkfilter.rst
++
+ BLOCK LAYER
+ M:	Jens Axboe <[email protected]>
+ L:	[email protected]
+-- 
+2.20.1
+