Commit graph

336 commits

Author SHA1 Message Date
Ritesh Harjani (IBM)
f5ceb1bbc9 iomap: Fix iomap_adjust_read_range for plen calculation
If the extent spans the block that contains i_size, we need to handle
both halves separately so that we properly zero data in the page cache
for blocks that are entirely outside of i_size. But this is needed only
when i_size is within the current folio under processing.
"orig_pos + length > isize" can be true for all folios if the mapped
extent length is greater than the folio size. That is making plen to
break for every folio instead of only the last folio.

So use orig_plen for checking if "orig_pos + orig_plen > isize".

Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Link: https://lore.kernel.org/r/a32e5f9a4fcfdb99077300c4020ed7ae61d6e0f9.1715067055.git.ritesh.list@gmail.com
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
cc: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-06-05 17:27:03 +02:00
Zhang Yi
0841ea4a3b iomap: keep on increasing i_size in iomap_write_end()
Commit '943bc0882ceb ("iomap: don't increase i_size if it's not a write
operation")' breaks xfs with realtime device on generic/561, the problem
is when unaligned truncate down a xfs realtime inode with rtextsize > 1
fs block, xfs only zero out the EOF block but doesn't zero out the tail
blocks that aligned to rtextsize, so if we don't increase i_size in
iomap_write_end(), it could expose stale data after we do an append
write beyond the aligned EOF block.

xfs should zero out the tail blocks when truncate down, but before we
finish that, let's fix the issue by just revert the changes in
iomap_write_end().

Fixes: 943bc0882c ("iomap: don't increase i_size if it's not a write operation")
Reported-by: Chandan Babu R <chandanbabu@kernel.org>
Link: https://lore.kernel.org/linux-xfs/0b92a215-9d9b-3788-4504-a520778953c2@huaweicloud.com
Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Link: https://lore.kernel.org/r/20240603112222.2109341-1-yi.zhang@huaweicloud.com
Tested-by: Chandan Babu R <chandanbabu@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-06-05 17:23:39 +02:00
Xu Yang
4e527d5841 iomap: fault in smaller chunks for non-large folio mappings
Since commit (5d8edfb900 "iomap: Copy larger chunks from userspace"),
iomap will try to copy in larger chunks than PAGE_SIZE. However, if the
mapping doesn't support large folio, only one page of maximum 4KB will
be created and 4KB data will be writen to pagecache each time. Then,
next 4KB will be handled in next iteration. This will cause potential
write performance problem.

If chunk is 2MB, total 512 pages need to be handled finally. During this
period, fault_in_iov_iter_readable() is called to check iov_iter readable
validity. Since only 4KB will be handled each time, below address space
will be checked over and over again:

start         	end
-
buf,    	buf+2MB
buf+4KB, 	buf+2MB
buf+8KB, 	buf+2MB
...
buf+2044KB 	buf+2MB

Obviously the checking size is wrong since only 4KB will be handled each
time. So this will get a correct chunk to let iomap work well in non-large
folio case.

With this change, the write speed will be stable. Tested on ARM64 device.

Before:

 - dd if=/dev/zero of=/dev/sda bs=400K  count=10485  (334 MB/s)
 - dd if=/dev/zero of=/dev/sda bs=800K  count=5242   (278 MB/s)
 - dd if=/dev/zero of=/dev/sda bs=1600K count=2621   (204 MB/s)
 - dd if=/dev/zero of=/dev/sda bs=2200K count=1906   (170 MB/s)
 - dd if=/dev/zero of=/dev/sda bs=3000K count=1398   (150 MB/s)
 - dd if=/dev/zero of=/dev/sda bs=4500K count=932    (139 MB/s)

After:

 - dd if=/dev/zero of=/dev/sda bs=400K  count=10485  (339 MB/s)
 - dd if=/dev/zero of=/dev/sda bs=800K  count=5242   (330 MB/s)
 - dd if=/dev/zero of=/dev/sda bs=1600K count=2621   (332 MB/s)
 - dd if=/dev/zero of=/dev/sda bs=2200K count=1906   (333 MB/s)
 - dd if=/dev/zero of=/dev/sda bs=3000K count=1398   (333 MB/s)
 - dd if=/dev/zero of=/dev/sda bs=4500K count=932    (333 MB/s)

Fixes: 5d8edfb900 ("iomap: Copy larger chunks from userspace")
Cc: stable@vger.kernel.org
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Xu Yang <xu.yang_2@nxp.com>
Link: https://lore.kernel.org/r/20240521114939.2541461-2-xu.yang_2@nxp.com
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-05-24 13:34:07 +02:00
Linus Torvalds
ff9a79307f Kbuild updates for v6.10
- Avoid 'constexpr', which is a keyword in C23
 
  - Allow 'dtbs_check' and 'dt_compatible_check' run independently of
    'dt_binding_check'
 
  - Fix weak references to avoid GOT entries in position-independent
    code generation
 
  - Convert the last use of 'optional' property in arch/sh/Kconfig
 
  - Remove support for the 'optional' property in Kconfig
 
  - Remove support for Clang's ThinLTO caching, which does not work with
    the .incbin directive
 
  - Change the semantics of $(src) so it always points to the source
    directory, which fixes Makefile inconsistencies between upstream and
    downstream
 
  - Fix 'make tar-pkg' for RISC-V to produce a consistent package
 
  - Provide reasonable default coverage for objtool, sanitizers, and
    profilers
 
  - Remove redundant OBJECT_FILES_NON_STANDARD, KASAN_SANITIZE, etc.
 
  - Remove the last use of tristate choice in drivers/rapidio/Kconfig
 
  - Various cleanups and fixes in Kconfig
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Merge tag 'kbuild-v6.10' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild updates from Masahiro Yamada:

 - Avoid 'constexpr', which is a keyword in C23

 - Allow 'dtbs_check' and 'dt_compatible_check' run independently of
   'dt_binding_check'

 - Fix weak references to avoid GOT entries in position-independent code
   generation

 - Convert the last use of 'optional' property in arch/sh/Kconfig

 - Remove support for the 'optional' property in Kconfig

 - Remove support for Clang's ThinLTO caching, which does not work with
   the .incbin directive

 - Change the semantics of $(src) so it always points to the source
   directory, which fixes Makefile inconsistencies between upstream and
   downstream

 - Fix 'make tar-pkg' for RISC-V to produce a consistent package

 - Provide reasonable default coverage for objtool, sanitizers, and
   profilers

 - Remove redundant OBJECT_FILES_NON_STANDARD, KASAN_SANITIZE, etc.

 - Remove the last use of tristate choice in drivers/rapidio/Kconfig

 - Various cleanups and fixes in Kconfig

* tag 'kbuild-v6.10' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (46 commits)
  kconfig: use sym_get_choice_menu() in sym_check_prop()
  rapidio: remove choice for enumeration
  kconfig: lxdialog: remove initialization with A_NORMAL
  kconfig: m/nconf: merge two item_add_str() calls
  kconfig: m/nconf: remove dead code to display value of bool choice
  kconfig: m/nconf: remove dead code to display children of choice members
  kconfig: gconf: show checkbox for choice correctly
  kbuild: use GCOV_PROFILE and KCSAN_SANITIZE in scripts/Makefile.modfinal
  Makefile: remove redundant tool coverage variables
  kbuild: provide reasonable defaults for tool coverage
  modules: Drop the .export_symbol section from the final modules
  kconfig: use menu_list_for_each_sym() in sym_check_choice_deps()
  kconfig: use sym_get_choice_menu() in conf_write_defconfig()
  kconfig: add sym_get_choice_menu() helper
  kconfig: turn defaults and additional prompt for choice members into error
  kconfig: turn missing prompt for choice members into error
  kconfig: turn conf_choice() into void function
  kconfig: use linked list in sym_set_changed()
  kconfig: gconf: use MENU_CHANGED instead of SYMBOL_CHANGED
  kconfig: gconf: remove debug code
  ...
2024-05-18 12:39:20 -07:00
Masahiro Yamada
b1992c3772 kbuild: use $(src) instead of $(srctree)/$(src) for source directory
Kbuild conventionally uses $(obj)/ for generated files, and $(src)/ for
checked-in source files. It is merely a convention without any functional
difference. In fact, $(obj) and $(src) are exactly the same, as defined
in scripts/Makefile.build:

    src := $(obj)

When the kernel is built in a separate output directory, $(src) does
not accurately reflect the source directory location. While Kbuild
resolves this discrepancy by specifying VPATH=$(srctree) to search for
source files, it does not cover all cases. For example, when adding a
header search path for local headers, -I$(srctree)/$(src) is typically
passed to the compiler.

This introduces inconsistency between upstream and downstream Makefiles
because $(src) is used instead of $(srctree)/$(src) for the latter.

To address this inconsistency, this commit changes the semantics of
$(src) so that it always points to the directory in the source tree.

Going forward, the variables used in Makefiles will have the following
meanings:

  $(obj)     - directory in the object tree
  $(src)     - directory in the source tree  (changed by this commit)
  $(objtree) - the top of the kernel object tree
  $(srctree) - the top of the kernel source tree

Consequently, $(srctree)/$(src) in upstream Makefiles need to be replaced
with $(src).

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
2024-05-10 04:34:52 +09:00
Zhang Yi
e1f453d433
iomap: do some small logical cleanup in buffered write
Since iomap_write_end() can never return a partial write length, the
comparison between written, copied and bytes becomes useless, just
merge them with the unwritten branch.

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Link: https://lore.kernel.org/r/20240320110548.2200662-10-yi.zhang@huaweicloud.com
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-04-25 14:23:54 +02:00
Zhang Yi
815f4b633b
iomap: make iomap_write_end() return a boolean
For now, we can make sure iomap_write_end() always return 0 or copied
bytes, so instead of return written bytes, convert to return a boolean
to indicate the copied bytes have been written to the pagecache.

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Link: https://lore.kernel.org/r/20240320110548.2200662-9-yi.zhang@huaweicloud.com
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-04-25 14:23:54 +02:00
Zhang Yi
1a61d74932
iomap: use a new variable to handle the written bytes in iomap_write_iter()
In iomap_write_iter(), the status variable used to receive the return
value from iomap_write_end() is confusing, replace it with a new written
variable to represent the written bytes in each cycle, no logic changes.

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Link: https://lore.kernel.org/r/20240320110548.2200662-8-yi.zhang@huaweicloud.com
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-04-25 14:23:54 +02:00
Zhang Yi
943bc0882c
iomap: don't increase i_size if it's not a write operation
Increase i_size in iomap_zero_range() and iomap_unshare_iter() is not
needed, the caller should handle it. Especially, when truncate partial
block, we should not increase i_size beyond the new EOF here. It doesn't
affect xfs and gfs2 now because they set the new file size after zero
out, it doesn't matter that a transient increase in i_size, but it will
affect ext4 because it set file size before truncate. So move the i_size
updating logic to iomap_write_iter().

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Link: https://lore.kernel.org/r/20240320110548.2200662-7-yi.zhang@huaweicloud.com
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-04-25 14:23:54 +02:00
Zhang Yi
89c6c1d91a
iomap: drop the write failure handles when unsharing and zeroing
Unsharing and zeroing can only happen within EOF, so there is never a
need to perform posteof pagecache truncation if write begin fails, also
partial write could never theoretically happened from iomap_write_end(),
so remove both of them.

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Link: https://lore.kernel.org/r/20240320110548.2200662-6-yi.zhang@huaweicloud.com
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-04-25 14:23:53 +02:00
Christoph Hellwig
0fac04e4e0
iomap: convert iomap_writepages to writeack_iter
This removes one indirect function call per folio, and adds type safety
by not casting through a void pointer.

Based on a patch by Matthew Wilcox.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20240412061614.1511629-1-hch@lst.de
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-04-15 14:25:55 +02:00
Christian Brauner
86835c39e0 vfs-6.9.rw_hint
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Merge tag 'vfs-6.9.rw_hint' of gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs

Pull write hint fix from Christian Brauner:

UFS devices are widely used in mobile applications, e.g. in smartphones.
UFS vendors need data lifetime information to achieve good performance.
Providing data lifetime information to UFS devices can result in up to
40% lower write amplification. Hence this patch series that restores the
bi_write_hint member in struct bio. After this patch series has been
merged, patches that implement data lifetime support in the SCSI disk
(sd) driver will be sent to the Linux kernel SCSI maintainer.

The following changes are included in this patch series:

- Improvements for the F_GET_RW_HINT and F_SET_RW_HINT fcntls.
- Move enum rw_hint into a new header file.
- Support F_SET_RW_HINT for block devices to make it easy to test data
  lifetime support.
- Restore the bio.bi_write_hint member and restore support in the VFS
  layer and also in the block layer for data lifetime information.

The shell script that has been used to test the patch series combined
with the SCSI patches is available at the end of this cover letter.

* tag 'vfs-6.9.rw_hint' of gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs:
  block, fs: Restore the per-bio/request data lifetime fields
  fs: Propagate write hints to the struct block_device inode
  fs: Move enum rw_hint into a new header file
  fs: Split fcntl_rw_hint()
  fs: Verify write lifetime constants at compile time
  fs: Fix rw_hint validation

Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-03-04 18:35:21 +01:00
Kassey Li
dcd04ea587 iomap: Add processed for iomap_iter
processed: The number of bytes processed by the body in the
most recent  iteration, or a negative errno. 0 causes the iteration to
stop.

The processed is useful to check when the loop breaks.

Signed-off-by: Kassey Li <quic_yingangl@quicinc.com>
Link: https://lore.kernel.org/r/20240219021138.3481763-1-quic_yingangl@quicinc.com
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-02-21 08:37:50 +01:00
Zhang Yi
54943abce0 iomap: add pos and dirty_len into trace_iomap_writepage_map
Since commit fd07e0aa23c4 ("iomap: map multiple blocks at a time"), we
could map multi-blocks once a time, and the dirty_len indicates the
expected map length, map_len won't large than it. The pos and dirty_len
means the dirty range that should be mapped to write, add them into
trace_iomap_writepage_map() could be more useful for debug.

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Link: https://lore.kernel.org/r/20240220115759.3445025-1-yi.zhang@huaweicloud.com
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-02-21 08:35:20 +01:00
Bart Van Assche
449813515d
block, fs: Restore the per-bio/request data lifetime fields
Restore support for passing data lifetime information from filesystems to
block drivers. This patch reverts commit b179c98f76 ("block: Remove
request.write_hint") and commit c75e707fe1 ("block: remove the
per-bio/request write hint").

This patch does not modify the size of struct bio because the new
bi_write_hint member fills a hole in struct bio. pahole reports the
following for struct bio on an x86_64 system with this patch applied:

        /* size: 112, cachelines: 2, members: 20 */
        /* sum members: 110, holes: 1, sum holes: 2 */
        /* last cacheline: 48 bytes */

Reviewed-by: Kanchan Joshi <joshi.k@samsung.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20240202203926.2478590-7-bvanassche@acm.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-02-06 14:31:05 +01:00
Christoph Hellwig
19871b5c7a iomap: pass the length of the dirty region to ->map_blocks
Let the file system know how much dirty data exists at the passed
in offset.  This allows file systems to allocate the right amount
of space that actually is written back if they can't eagerly
convert (e.g. because they don't support unwritten extents).

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20231207072710.176093-15-hch@lst.de
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-02-01 14:20:13 +01:00
Christoph Hellwig
30deff8531 iomap: map multiple blocks at a time
The ->map_blocks interface returns a valid range for writeback, but we
still call back into it for every block, which is a bit inefficient.

Change iomap_writepage_map to use the valid range in the map until the
end of the folio or the dirty range inside the folio instead of calling
back into every block.

Note that the range is not used over folio boundaries as we need to be
able to check the mapping sequence count under the folio lock.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20231207072710.176093-14-hch@lst.de
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-02-01 14:20:13 +01:00
Christoph Hellwig
410bb2ce61 iomap: submit ioends immediately
Currently the writeback code delays submitting fill ioends until we
reach the end of the folio.  The reason for that is that otherwise
the end I/O handler could clear the writeback bit before we've even
finished submitting all I/O for the folio.

Add a bias to ifs->write_bytes_pending while we are submitting I/O
for a folio so that it never reaches zero until all I/O is completed
to prevent the early writeback bit clearing, and remove the now
superfluous submit_list.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20231207072710.176093-13-hch@lst.de
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-02-01 14:20:13 +01:00
Christoph Hellwig
f525152a0f iomap: factor out a iomap_writepage_map_block helper
Split the loop body that calls into the file system to map a block and
add it to the ioend into a separate helper to prefer for refactoring of
the surrounding code.

Note that this was the only place in iomap_writepage_map that could
return an error, so include the call to ->discard_folio into the new
helper as that will help to avoid code duplication in the future.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20231207072710.176093-12-hch@lst.de
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-02-01 14:20:12 +01:00
Christoph Hellwig
6b865d6530 iomap: only call mapping_set_error once for each failed bio
Instead of clling mapping_set_error once per folio, only do that once
per bio, and consolidate all the writeback error handling code in
iomap_finish_ioend.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20231207072710.176093-11-hch@lst.de
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-02-01 14:20:12 +01:00
Christoph Hellwig
ae5535efd8 iomap: don't chain bios
Back in the days when a single bio could only be filled to the hardware
limits, and we scheduled a work item for each bio completion, chaining
multiple bios for a single ioend made a lot of sense to reduce the number
of completions.  But these days bios can be filled until we reach the
number of vectors or total size limit, which means we can always fit at
least 1 megabyte worth of data in the worst case, but usually a lot more
due to large folios.  The only thing bio chaining is buying us now is
to reduce the size of the allocation from an ioend with an embedded bio
into a plain bio, which is a 52 bytes differences on 64-bit systems.

This is not worth the added complexity, so remove the bio chaining and
only use the bio embedded into the ioend.  This will help to simplify
further changes to the iomap writeback code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20231207072710.176093-10-hch@lst.de
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-02-01 14:20:12 +01:00
Christoph Hellwig
dec3a7b3aa iomap: move the iomap_sector sector calculation out of iomap_add_to_ioend
The calculation in iomap_sector is pretty trivial and most of the time
iomap_add_to_ioend only callers either iomap_can_add_to_ioend or
iomap_alloc_ioend from a single invocation.

Calculate the sector in the two lower level functions and stop passing it
from iomap_add_to_ioend and update the iomap_alloc_ioend argument passing
order to match that of iomap_add_to_ioend.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20231207072710.176093-9-hch@lst.de
Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-02-01 14:20:12 +01:00
Christoph Hellwig
7edfc610ec iomap: clean up the iomap_alloc_ioend calling convention
Switch to the same argument order as iomap_writepage_map and remove the
ifs argument that can be trivially recalculated.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20231207072710.176093-8-hch@lst.de
Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-02-01 14:20:11 +01:00
Christoph Hellwig
cc9542534b iomap: move all remaining per-folio logic into iomap_writepage_map
Move the tracepoint and the iomap check from iomap_do_writepage into
iomap_writepage_map.  This keeps all logic in one places, and leaves
iomap_do_writepage just as the wrapper for the callback conventions of
write_cache_pages, which will go away when that is converted to an
iterator.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20231207072710.176093-7-hch@lst.de
Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-02-01 14:20:11 +01:00
Christoph Hellwig
e3a491a26b iomap: factor out a iomap_writepage_handle_eof helper
Most of iomap_do_writepage is dedidcated to handling a folio crossing or
beyond i_size.  Split this is into a separate helper and update the
commens to deal with folios instead of pages and make them more readable.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20231207072710.176093-6-hch@lst.de
Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-02-01 14:20:11 +01:00
Christoph Hellwig
c2dc7e5589 iomap: move the PF_MEMALLOC check to iomap_writepages
The iomap writepage implementation has been removed in commit
478af190cb ("iomap: remove iomap_writepage") and this code is now only
called through ->writepages which never happens from memory reclaim.

Nove the check from iomap_do_writepage to iomap_writepages so that is
only called once per ->writepage invocation.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20231207072710.176093-5-hch@lst.de
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-02-01 14:20:11 +01:00
Christoph Hellwig
432acd550e iomap: move the io_folios field out of struct iomap_ioend
The io_folios member in struct iomap_ioend counts the number of folios
added to an ioend.  It is only used at submission time and can thus be
moved to iomap_writepage_ctx instead.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20231207072710.176093-4-hch@lst.de
Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-02-01 14:20:10 +01:00
Christoph Hellwig
80d012e988 iomap: treat inline data in iomap_writepage_map as an I/O error
iomap_writepage_map aready warns about inline data, but then just ignores
it.  Treat it as an error and return -EIO.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20231207072710.176093-3-hch@lst.de
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-02-01 14:20:10 +01:00
Christoph Hellwig
7ea1d9b4a8 iomap: clear the per-folio dirty bits on all writeback failures
write_cache_pages always clear the page dirty bit before calling into the
file systems, and leaves folios with a writeback failure without the
dirty bit after return.  We also clear the per-block writeback bits for
writeback failures unless no I/O has submitted, which will leave the
folio in an inconsistent state where it doesn't have the folio dirty,
but one or more per-block dirty bits.  This seems to be due the place
where the iomap_clear_range_dirty call was inserted into the existing
not very clearly structured code when adding per-block dirty bit support
and not actually intentional.  Switch to always clearing the dirty on
writeback failure.

Fixes: 4ce02c6797 ("iomap: Add per-block dirty state tracking to improve performance")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20231207072710.176093-2-hch@lst.de
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-02-01 14:20:06 +01:00
Matthew Wilcox (Oracle)
6eaa266b54 mm: add folio_fill_tail() and use it in iomap
The iomap code was limited to PAGE_SIZE bytes; generalise it to cover
an arbitrary-sized folio, and move it to be a common helper.

[akpm@linux-foundation.org: fix folio_fill_tail(), per Andreas Gruenbacher]
Link: https://lkml.kernel.org/r/20231107212643.3490372-3-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: Darrick J. Wong <djwong@kernel.org>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-12-10 16:51:36 -08:00
Linus Torvalds
ecae0bd517 Many singleton patches against the MM code. The patch series which are
included in this merge do the following:
 
 - Kemeng Shi has contributed some compation maintenance work in the
   series "Fixes and cleanups to compaction".
 
 - Joel Fernandes has a patchset ("Optimize mremap during mutual
   alignment within PMD") which fixes an obscure issue with mremap()'s
   pagetable handling during a subsequent exec(), based upon an
   implementation which Linus suggested.
 
 - More DAMON/DAMOS maintenance and feature work from SeongJae Park i the
   following patch series:
 
 	mm/damon: misc fixups for documents, comments and its tracepoint
 	mm/damon: add a tracepoint for damos apply target regions
 	mm/damon: provide pseudo-moving sum based access rate
 	mm/damon: implement DAMOS apply intervals
 	mm/damon/core-test: Fix memory leaks in core-test
 	mm/damon/sysfs-schemes: Do DAMOS tried regions update for only one apply interval
 
 - In the series "Do not try to access unaccepted memory" Adrian Hunter
   provides some fixups for the recently-added "unaccepted memory' feature.
   To increase the feature's checking coverage.  "Plug a few gaps where
   RAM is exposed without checking if it is unaccepted memory".
 
 - In the series "cleanups for lockless slab shrink" Qi Zheng has done
   some maintenance work which is preparation for the lockless slab
   shrinking code.
 
 - Qi Zheng has redone the earlier (and reverted) attempt to make slab
   shrinking lockless in the series "use refcount+RCU method to implement
   lockless slab shrink".
 
 - David Hildenbrand contributes some maintenance work for the rmap code
   in the series "Anon rmap cleanups".
 
 - Kefeng Wang does more folio conversions and some maintenance work in
   the migration code.  Series "mm: migrate: more folio conversion and
   unification".
 
 - Matthew Wilcox has fixed an issue in the buffer_head code which was
   causing long stalls under some heavy memory/IO loads.  Some cleanups
   were added on the way.  Series "Add and use bdev_getblk()".
 
 - In the series "Use nth_page() in place of direct struct page
   manipulation" Zi Yan has fixed a potential issue with the direct
   manipulation of hugetlb page frames.
 
 - In the series "mm: hugetlb: Skip initialization of gigantic tail
   struct pages if freed by HVO" has improved our handling of gigantic
   pages in the hugetlb vmmemmep optimizaton code.  This provides
   significant boot time improvements when significant amounts of gigantic
   pages are in use.
 
 - Matthew Wilcox has sent the series "Small hugetlb cleanups" - code
   rationalization and folio conversions in the hugetlb code.
 
 - Yin Fengwei has improved mlock()'s handling of large folios in the
   series "support large folio for mlock"
 
 - In the series "Expose swapcache stat for memcg v1" Liu Shixin has
   added statistics for memcg v1 users which are available (and useful)
   under memcg v2.
 
 - Florent Revest has enhanced the MDWE (Memory-Deny-Write-Executable)
   prctl so that userspace may direct the kernel to not automatically
   propagate the denial to child processes.  The series is named "MDWE
   without inheritance".
 
 - Kefeng Wang has provided the series "mm: convert numa balancing
   functions to use a folio" which does what it says.
 
 - In the series "mm/ksm: add fork-exec support for prctl" Stefan Roesch
   makes is possible for a process to propagate KSM treatment across
   exec().
 
 - Huang Ying has enhanced memory tiering's calculation of memory
   distances.  This is used to permit the dax/kmem driver to use "high
   bandwidth memory" in addition to Optane Data Center Persistent Memory
   Modules (DCPMM).  The series is named "memory tiering: calculate
   abstract distance based on ACPI HMAT"
 
 - In the series "Smart scanning mode for KSM" Stefan Roesch has
   optimized KSM by teaching it to retain and use some historical
   information from previous scans.
 
 - Yosry Ahmed has fixed some inconsistencies in memcg statistics in the
   series "mm: memcg: fix tracking of pending stats updates values".
 
 - In the series "Implement IOCTL to get and optionally clear info about
   PTEs" Peter Xu has added an ioctl to /proc/<pid>/pagemap which permits
   us to atomically read-then-clear page softdirty state.  This is mainly
   used by CRIU.
 
 - Hugh Dickins contributed the series "shmem,tmpfs: general maintenance"
   - a bunch of relatively minor maintenance tweaks to this code.
 
 - Matthew Wilcox has increased the use of the VMA lock over file-backed
   page faults in the series "Handle more faults under the VMA lock".  Some
   rationalizations of the fault path became possible as a result.
 
 - In the series "mm/rmap: convert page_move_anon_rmap() to
   folio_move_anon_rmap()" David Hildenbrand has implemented some cleanups
   and folio conversions.
 
 - In the series "various improvements to the GUP interface" Lorenzo
   Stoakes has simplified and improved the GUP interface with an eye to
   providing groundwork for future improvements.
 
 - Andrey Konovalov has sent along the series "kasan: assorted fixes and
   improvements" which does those things.
 
 - Some page allocator maintenance work from Kemeng Shi in the series
   "Two minor cleanups to break_down_buddy_pages".
 
 - In thes series "New selftest for mm" Breno Leitao has developed
   another MM self test which tickles a race we had between madvise() and
   page faults.
 
 - In the series "Add folio_end_read" Matthew Wilcox provides cleanups
   and an optimization to the core pagecache code.
 
 - Nhat Pham has added memcg accounting for hugetlb memory in the series
   "hugetlb memcg accounting".
 
 - Cleanups and rationalizations to the pagemap code from Lorenzo
   Stoakes, in the series "Abstract vma_merge() and split_vma()".
 
 - Audra Mitchell has fixed issues in the procfs page_owner code's new
   timestamping feature which was causing some misbehaviours.  In the
   series "Fix page_owner's use of free timestamps".
 
 - Lorenzo Stoakes has fixed the handling of new mappings of sealed files
   in the series "permit write-sealed memfd read-only shared mappings".
 
 - Mike Kravetz has optimized the hugetlb vmemmap optimization in the
   series "Batch hugetlb vmemmap modification operations".
 
 - Some buffer_head folio conversions and cleanups from Matthew Wilcox in
   the series "Finish the create_empty_buffers() transition".
 
 - As a page allocator performance optimization Huang Ying has added
   automatic tuning to the allocator's per-cpu-pages feature, in the series
   "mm: PCP high auto-tuning".
 
 - Roman Gushchin has contributed the patchset "mm: improve performance
   of accounted kernel memory allocations" which improves their performance
   by ~30% as measured by a micro-benchmark.
 
 - folio conversions from Kefeng Wang in the series "mm: convert page
   cpupid functions to folios".
 
 - Some kmemleak fixups in Liu Shixin's series "Some bugfix about
   kmemleak".
 
 - Qi Zheng has improved our handling of memoryless nodes by keeping them
   off the allocation fallback list.  This is done in the series "handle
   memoryless nodes more appropriately".
 
 - khugepaged conversions from Vishal Moola in the series "Some
   khugepaged folio conversions".
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Merge tag 'mm-stable-2023-11-01-14-33' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull MM updates from Andrew Morton:
 "Many singleton patches against the MM code. The patch series which are
  included in this merge do the following:

   - Kemeng Shi has contributed some compation maintenance work in the
     series 'Fixes and cleanups to compaction'

   - Joel Fernandes has a patchset ('Optimize mremap during mutual
     alignment within PMD') which fixes an obscure issue with mremap()'s
     pagetable handling during a subsequent exec(), based upon an
     implementation which Linus suggested

   - More DAMON/DAMOS maintenance and feature work from SeongJae Park i
     the following patch series:

	mm/damon: misc fixups for documents, comments and its tracepoint
	mm/damon: add a tracepoint for damos apply target regions
	mm/damon: provide pseudo-moving sum based access rate
	mm/damon: implement DAMOS apply intervals
	mm/damon/core-test: Fix memory leaks in core-test
	mm/damon/sysfs-schemes: Do DAMOS tried regions update for only one apply interval

   - In the series 'Do not try to access unaccepted memory' Adrian
     Hunter provides some fixups for the recently-added 'unaccepted
     memory' feature. To increase the feature's checking coverage. 'Plug
     a few gaps where RAM is exposed without checking if it is
     unaccepted memory'

   - In the series 'cleanups for lockless slab shrink' Qi Zheng has done
     some maintenance work which is preparation for the lockless slab
     shrinking code

   - Qi Zheng has redone the earlier (and reverted) attempt to make slab
     shrinking lockless in the series 'use refcount+RCU method to
     implement lockless slab shrink'

   - David Hildenbrand contributes some maintenance work for the rmap
     code in the series 'Anon rmap cleanups'

   - Kefeng Wang does more folio conversions and some maintenance work
     in the migration code. Series 'mm: migrate: more folio conversion
     and unification'

   - Matthew Wilcox has fixed an issue in the buffer_head code which was
     causing long stalls under some heavy memory/IO loads. Some cleanups
     were added on the way. Series 'Add and use bdev_getblk()'

   - In the series 'Use nth_page() in place of direct struct page
     manipulation' Zi Yan has fixed a potential issue with the direct
     manipulation of hugetlb page frames

   - In the series 'mm: hugetlb: Skip initialization of gigantic tail
     struct pages if freed by HVO' has improved our handling of gigantic
     pages in the hugetlb vmmemmep optimizaton code. This provides
     significant boot time improvements when significant amounts of
     gigantic pages are in use

   - Matthew Wilcox has sent the series 'Small hugetlb cleanups' - code
     rationalization and folio conversions in the hugetlb code

   - Yin Fengwei has improved mlock()'s handling of large folios in the
     series 'support large folio for mlock'

   - In the series 'Expose swapcache stat for memcg v1' Liu Shixin has
     added statistics for memcg v1 users which are available (and
     useful) under memcg v2

   - Florent Revest has enhanced the MDWE (Memory-Deny-Write-Executable)
     prctl so that userspace may direct the kernel to not automatically
     propagate the denial to child processes. The series is named 'MDWE
     without inheritance'

   - Kefeng Wang has provided the series 'mm: convert numa balancing
     functions to use a folio' which does what it says

   - In the series 'mm/ksm: add fork-exec support for prctl' Stefan
     Roesch makes is possible for a process to propagate KSM treatment
     across exec()

   - Huang Ying has enhanced memory tiering's calculation of memory
     distances. This is used to permit the dax/kmem driver to use 'high
     bandwidth memory' in addition to Optane Data Center Persistent
     Memory Modules (DCPMM). The series is named 'memory tiering:
     calculate abstract distance based on ACPI HMAT'

   - In the series 'Smart scanning mode for KSM' Stefan Roesch has
     optimized KSM by teaching it to retain and use some historical
     information from previous scans

   - Yosry Ahmed has fixed some inconsistencies in memcg statistics in
     the series 'mm: memcg: fix tracking of pending stats updates
     values'

   - In the series 'Implement IOCTL to get and optionally clear info
     about PTEs' Peter Xu has added an ioctl to /proc/<pid>/pagemap
     which permits us to atomically read-then-clear page softdirty
     state. This is mainly used by CRIU

   - Hugh Dickins contributed the series 'shmem,tmpfs: general
     maintenance', a bunch of relatively minor maintenance tweaks to
     this code

   - Matthew Wilcox has increased the use of the VMA lock over
     file-backed page faults in the series 'Handle more faults under the
     VMA lock'. Some rationalizations of the fault path became possible
     as a result

   - In the series 'mm/rmap: convert page_move_anon_rmap() to
     folio_move_anon_rmap()' David Hildenbrand has implemented some
     cleanups and folio conversions

   - In the series 'various improvements to the GUP interface' Lorenzo
     Stoakes has simplified and improved the GUP interface with an eye
     to providing groundwork for future improvements

   - Andrey Konovalov has sent along the series 'kasan: assorted fixes
     and improvements' which does those things

   - Some page allocator maintenance work from Kemeng Shi in the series
     'Two minor cleanups to break_down_buddy_pages'

   - In thes series 'New selftest for mm' Breno Leitao has developed
     another MM self test which tickles a race we had between madvise()
     and page faults

   - In the series 'Add folio_end_read' Matthew Wilcox provides cleanups
     and an optimization to the core pagecache code

   - Nhat Pham has added memcg accounting for hugetlb memory in the
     series 'hugetlb memcg accounting'

   - Cleanups and rationalizations to the pagemap code from Lorenzo
     Stoakes, in the series 'Abstract vma_merge() and split_vma()'

   - Audra Mitchell has fixed issues in the procfs page_owner code's new
     timestamping feature which was causing some misbehaviours. In the
     series 'Fix page_owner's use of free timestamps'

   - Lorenzo Stoakes has fixed the handling of new mappings of sealed
     files in the series 'permit write-sealed memfd read-only shared
     mappings'

   - Mike Kravetz has optimized the hugetlb vmemmap optimization in the
     series 'Batch hugetlb vmemmap modification operations'

   - Some buffer_head folio conversions and cleanups from Matthew Wilcox
     in the series 'Finish the create_empty_buffers() transition'

   - As a page allocator performance optimization Huang Ying has added
     automatic tuning to the allocator's per-cpu-pages feature, in the
     series 'mm: PCP high auto-tuning'

   - Roman Gushchin has contributed the patchset 'mm: improve
     performance of accounted kernel memory allocations' which improves
     their performance by ~30% as measured by a micro-benchmark

   - folio conversions from Kefeng Wang in the series 'mm: convert page
     cpupid functions to folios'

   - Some kmemleak fixups in Liu Shixin's series 'Some bugfix about
     kmemleak'

   - Qi Zheng has improved our handling of memoryless nodes by keeping
     them off the allocation fallback list. This is done in the series
     'handle memoryless nodes more appropriately'

   - khugepaged conversions from Vishal Moola in the series 'Some
     khugepaged folio conversions'"

[ bcachefs conflicts with the dynamically allocated shrinkers have been
  resolved as per Stephen Rothwell in

     https://lore.kernel.org/all/20230913093553.4290421e@canb.auug.org.au/

  with help from Qi Zheng.

  The clone3 test filtering conflict was half-arsed by yours truly ]

* tag 'mm-stable-2023-11-01-14-33' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (406 commits)
  mm/damon/sysfs: update monitoring target regions for online input commit
  mm/damon/sysfs: remove requested targets when online-commit inputs
  selftests: add a sanity check for zswap
  Documentation: maple_tree: fix word spelling error
  mm/vmalloc: fix the unchecked dereference warning in vread_iter()
  zswap: export compression failure stats
  Documentation: ubsan: drop "the" from article title
  mempolicy: migration attempt to match interleave nodes
  mempolicy: mmap_lock is not needed while migrating folios
  mempolicy: alloc_pages_mpol() for NUMA policy without vma
  mm: add page_rmappable_folio() wrapper
  mempolicy: remove confusing MPOL_MF_LAZY dead code
  mempolicy: mpol_shared_policy_init() without pseudo-vma
  mempolicy trivia: use pgoff_t in shared mempolicy tree
  mempolicy trivia: slightly more consistent naming
  mempolicy trivia: delete those ancient pr_debug()s
  mempolicy: fix migrate_pages(2) syscall return nr_failed
  kernfs: drop shared NUMA mempolicy hooks
  hugetlbfs: drop shared NUMA mempolicy pretence
  mm/damon/sysfs-test: add a unit test for damon_sysfs_set_targets()
  ...
2023-11-02 19:38:47 -10:00
Jan Stancek
3ac974796e iomap: fix short copy in iomap_write_iter()
Starting with commit 5d8edfb900 ("iomap: Copy larger chunks from
userspace"), iomap_write_iter() can get into endless loop. This can
be reproduced with LTP writev07 which uses partially valid iovecs:
        struct iovec wr_iovec[] = {
                { buffer, 64 },
                { bad_addr, 64 },
                { buffer + 64, 64 },
                { buffer + 64 * 2, 64 },
        };

commit bc1bb416bb ("generic_perform_write()/iomap_write_actor():
saner logics for short copy") previously introduced the logic, which
made short copy retry in next iteration with amount of "bytes" it
managed to copy:

                if (unlikely(status == 0)) {
                        /*
                         * A short copy made iomap_write_end() reject the
                         * thing entirely.  Might be memory poisoning
                         * halfway through, might be a race with munmap,
                         * might be severe memory pressure.
                         */
                        if (copied)
                                bytes = copied;

However, since 5d8edfb900 "bytes" is no longer carried into next
iteration, because it is now always initialized at the beginning of
the loop. And for iov_iter_count < PAGE_SIZE, "bytes" ends up with
same value as previous iteration, making the loop retry same copy
over and over, which leads to writev07 testcase hanging.

Make next iteration retry with amount of bytes we managed to copy.

Fixes: 5d8edfb900 ("iomap: Copy larger chunks from userspace")
Signed-off-by: Jan Stancek <jstancek@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2023-10-19 09:41:36 -07:00
Matthew Wilcox (Oracle)
7a4847e54c iomap: use folio_end_read()
Combine the setting of the uptodate flag with the clearing of the locked
flag.

Link: https://lkml.kernel.org/r/20231004165317.1061855-7-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Richard Henderson <richard.henderson@linaro.org>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-10-18 14:34:16 -07:00
Matthew Wilcox (Oracle)
f45b494e2a iomap: protect read_bytes_pending with the state_lock
Perform one atomic operation (acquiring the spinlock) instead of two
(spinlock & atomic_sub) per read completion.

Link: https://lkml.kernel.org/r/20231004165317.1061855-3-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Richard Henderson <richard.henderson@linaro.org>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-10-18 14:34:16 -07:00
Matthew Wilcox (Oracle)
279d5fc322 iomap: hold state_lock over call to ifs_set_range_uptodate()
Patch series "Add folio_end_read", v2.

The core of this patchset is the new folio_end_read() call which
filesystems can use when finishing a page cache read instead of separate
calls to mark the folio uptodate and unlock it.  As an illustration of its
use, I converted ext4, iomap & mpage; more can be converted.

I think that's useful by itself, but the interesting optimisation is that
we can implement that with a single XOR instruction that sets the uptodate
bit, clears the lock bit, tests the waiter bit and provides a write memory
barrier.  That removes one memory barrier and one atomic instruction from
each page read, which seems worth doing.  That's in patch 15.

The last two patches could be a separate series, but basically we can do
the same thing with the writeback flag that we do with the unlock flag;
clear it and test the waiters bit at the same time.


This patch (of 17):

This is really preparation for the next patch, but it lets us call
folio_mark_uptodate() in just one place instead of two.

Link: https://lkml.kernel.org/r/20231004165317.1061855-1-willy@infradead.org
Link: https://lkml.kernel.org/r/20231004165317.1061855-2-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: Richard Henderson <richard.henderson@linaro.org>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-10-18 14:34:16 -07:00
Geert Uytterhoeven
684f7e6d28 iomap: Spelling s/preceeding/preceding/g
Fix a misspelling of "preceding".

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Bill O'Donnell <bodonnel@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2023-09-28 09:26:58 -07:00
Darrick J. Wong
a5f31a5028 iomap: convert iomap_unshare_iter to use large folios
Convert iomap_unshare_iter to create large folios if possible, since the
write and zeroing paths already do that.  I think this got missed in the
conversion of the write paths that landed in 6.6-rc1.

Cc: ritesh.list@gmail.com, willy@infradead.org
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
2023-09-19 09:05:35 -07:00
Darrick J. Wong
35d30c9cf1 iomap: don't skip reading in !uptodate folios when unsharing a range
Prior to commit a01b8f2252, we would always read in the contents of a
!uptodate folio prior to writing userspace data into the folio,
allocated a folio state object, etc.  Ritesh introduced an optimization
that skips all of that if the write would cover the entire folio.

Unfortunately, the optimization misses the unshare case, where we always
have to read in the folio contents since there isn't a data buffer
supplied by userspace.  This can result in stale kernel memory exposure
if userspace issues a FALLOC_FL_UNSHARE_RANGE call on part of a shared
file that isn't already cached.

This was caught by observing fstests regressions in the "unshare around"
mechanism that is used for unaligned writes to a reflinked realtime
volume when the realtime extent size is larger than 1FSB, though I think
it applies to any shared file.

Cc: ritesh.list@gmail.com, willy@infradead.org
Fixes: a01b8f2252 ("iomap: Allocate ifs in ->write_begin() early")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
2023-09-18 15:57:39 -07:00
Linus Torvalds
3d3dfeb3ae for-6.6/block-2023-08-28
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Merge tag 'for-6.6/block-2023-08-28' of git://git.kernel.dk/linux

Pull block updates from Jens Axboe:
 "Pretty quiet round for this release. This contains:

   - Add support for zoned storage to ublk (Andreas, Ming)

   - Series improving performance for drivers that mark themselves as
     needing a blocking context for issue (Bart)

   - Cleanup the flush logic (Chengming)

   - sed opal keyring support (Greg)

   - Fixes and improvements to the integrity support (Jinyoung)

   - Add some exports for bcachefs that we can hopefully delete again in
     the future (Kent)

   - deadline throttling fix (Zhiguo)

   - Series allowing building the kernel without buffer_head support
     (Christoph)

   - Sanitize the bio page adding flow (Christoph)

   - Write back cache fixes (Christoph)

   - MD updates via Song:
      - Fix perf regression for raid0 large sequential writes (Jan)
      - Fix split bio iostat for raid0 (David)
      - Various raid1 fixes (Heinz, Xueshi)
      - raid6test build fixes (WANG)
      - Deprecate bitmap file support (Christoph)
      - Fix deadlock with md sync thread (Yu)
      - Refactor md io accounting (Yu)
      - Various non-urgent fixes (Li, Yu, Jack)

   - Various fixes and cleanups (Arnd, Azeem, Chengming, Damien, Li,
     Ming, Nitesh, Ruan, Tejun, Thomas, Xu)"

* tag 'for-6.6/block-2023-08-28' of git://git.kernel.dk/linux: (113 commits)
  block: use strscpy() to instead of strncpy()
  block: sed-opal: keyring support for SED keys
  block: sed-opal: Implement IOC_OPAL_REVERT_LSP
  block: sed-opal: Implement IOC_OPAL_DISCOVERY
  blk-mq: prealloc tags when increase tagset nr_hw_queues
  blk-mq: delete redundant tagset map update when fallback
  blk-mq: fix tags leak when shrink nr_hw_queues
  ublk: zoned: support REQ_OP_ZONE_RESET_ALL
  md: raid0: account for split bio in iostat accounting
  md/raid0: Fix performance regression for large sequential writes
  md/raid0: Factor out helper for mapping and submitting a bio
  md raid1: allow writebehind to work on any leg device set WriteMostly
  md/raid1: hold the barrier until handle_read_error() finishes
  md/raid1: free the r1bio before waiting for blocked rdev
  md/raid1: call free_r1bio() before allow_barrier() in raid_end_bio_io()
  blk-cgroup: Fix NULL deref caused by blkg_policy_data being installed before init
  drivers/rnbd: restore sysfs interface to rnbd-client
  md/raid5-cache: fix null-ptr-deref for r5l_flush_stripe_to_raid()
  raid6: test: only check for Altivec if building on powerpc hosts
  raid6: test: make sure all intermediate and artifact files are .gitignored
  ...
2023-08-29 20:21:42 -07:00
Christoph Hellwig
2ba39cc46b fs: rename and move block_page_mkwrite_return
block_page_mkwrite_return is neither block nor mkwrite specific, and
should not be under CONFIG_BLOCK.  Move it to mm.h and rename it to
vmf_fs_error.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Christian Brauner <brauner@kernel.org>
Link: https://lore.kernel.org/r/20230801172201.1923299-3-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-08-02 09:13:09 -06:00
Darrick J. Wong
377698d4ab Improve iomap/xfs async dio write performance
iomap always punts async dio write completions to a workqueue, which has
 a cost in terms of efficiency (now you need an unrelated worker to
 process it) and latency (now you're bouncing a completion through an
 async worker, which is a classic slowdown scenario).
 
 io_uring handles IRQ completions via task_work, and for writes that
 don't need to do extra IO at completion time, we can safely complete
 them inline from that. This patchset adds IOCB_DIO_CALLER_COMP, which an
 IO issuer can set to inform the completion side that any extra work that
 needs doing for that completion can be punted to a safe task context.
 
 The iomap dio completion will happen in hard/soft irq context, and we
 need a saner context to process these completions. IOCB_DIO_CALLER_COMP
 is added, which can be set in a struct kiocb->ki_flags by the issuer. If
 the completion side of the iocb handling understands this flag, it can
 choose to set a kiocb->dio_complete() handler and just call ki_complete
 from IRQ context. The issuer must then ensure that this callback is
 processed from a task. io_uring punts IRQ completions to task_work
 already, so it's trivial wire it up to run more of the completion before
 posting a CQE. This is good for up to a 37% improvement in
 throughput/latency for low queue depth IO, patch 5 has the details.
 
 If we need to do real work at completion time, iomap will clear the
 IOMAP_DIO_CALLER_COMP flag.
 
 This work came about when Andres tested low queue depth dio writes for
 postgres and compared it to doing sync dio writes, showing that the
 async processing slows us down a lot.
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Merge tag 'xfs-async-dio.6-2023-08-01' of git://git.kernel.dk/linux into iomap-6.6-mergeA

Improve iomap/xfs async dio write performance

iomap always punts async dio write completions to a workqueue, which has
a cost in terms of efficiency (now you need an unrelated worker to
process it) and latency (now you're bouncing a completion through an
async worker, which is a classic slowdown scenario).

io_uring handles IRQ completions via task_work, and for writes that
don't need to do extra IO at completion time, we can safely complete
them inline from that. This patchset adds IOCB_DIO_CALLER_COMP, which an
IO issuer can set to inform the completion side that any extra work that
needs doing for that completion can be punted to a safe task context.

The iomap dio completion will happen in hard/soft irq context, and we
need a saner context to process these completions. IOCB_DIO_CALLER_COMP
is added, which can be set in a struct kiocb->ki_flags by the issuer. If
the completion side of the iocb handling understands this flag, it can
choose to set a kiocb->dio_complete() handler and just call ki_complete
from IRQ context. The issuer must then ensure that this callback is
processed from a task. io_uring punts IRQ completions to task_work
already, so it's trivial wire it up to run more of the completion before
posting a CQE. This is good for up to a 37% improvement in
throughput/latency for low queue depth IO, patch 5 has the details.

If we need to do real work at completion time, iomap will clear the
IOMAP_DIO_CALLER_COMP flag.

This work came about when Andres tested low queue depth dio writes for
postgres and compared it to doing sync dio writes, showing that the
async processing slows us down a lot.

* tag 'xfs-async-dio.6-2023-08-01' of git://git.kernel.dk/linux:
  iomap: support IOCB_DIO_CALLER_COMP
  io_uring/rw: add write support for IOCB_DIO_CALLER_COMP
  fs: add IOCB flags related to passing back dio completions
  iomap: add IOMAP_DIO_INLINE_COMP
  iomap: only set iocb->private for polled bio
  iomap: treat a write through cache the same as FUA
  iomap: use an unsigned type for IOMAP_DIO_* defines
  iomap: cleanup up iomap_dio_bio_end_io()

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2023-08-01 16:41:49 -07:00
Jens Axboe
8c052fb300 iomap: support IOCB_DIO_CALLER_COMP
If IOCB_DIO_CALLER_COMP is set, utilize that to set kiocb->dio_complete
handler and data for that callback. Rather than punt the completion to a
workqueue, we pass back the handler and data to the issuer and will get
a callback from a safe task context.

Using the following fio job to randomly dio write 4k blocks at
queue depths of 1..16:

fio --name=dio-write --filename=/data1/file --time_based=1 \
--runtime=10 --bs=4096 --rw=randwrite --norandommap --buffered=0 \
--cpus_allowed=4 --ioengine=io_uring --iodepth=$depth

shows the following results before and after this patch:

	Stock	Patched		Diff
=======================================
QD1	155K	162K		+ 4.5%
QD2	290K	313K		+ 7.9%
QD4	533K	597K		+12.0%
QD8	604K	827K		+36.9%
QD16	615K	845K		+37.4%

which shows nice wins all around. If we factored in per-IOP efficiency,
the wins look even nicer. This becomes apparent as queue depth rises,
as the offloaded workqueue completions runs out of steam.

Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-08-01 17:32:49 -06:00
Jens Axboe
7b3c14d1a9 iomap: add IOMAP_DIO_INLINE_COMP
Rather than gate whether or not we need to punt a dio completion to a
workqueue on whether the IO is a write or not, add an explicit flag for
it. For now we treat them the same, reads always set the flags and async
writes do not.

No functional changes in this patch.

Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-08-01 17:32:41 -06:00
Jens Axboe
daa99c5a33 iomap: only set iocb->private for polled bio
iocb->private is only used for polled IO, where the completer will
find the bio to poll through that field.

Assign it when we're submitting a polled bio, and get rid of the
dio->poll_bio indirection.

Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-08-01 17:32:38 -06:00
Jens Axboe
3a0be38cc8 iomap: treat a write through cache the same as FUA
Whether we have a write back cache and are using FUA or don't have
a write back cache at all is the same situation. Treat them the same.

This makes the IOMAP_DIO_WRITE_FUA name a bit misleading, as we have
two cases that provide stable writes:

1) Volatile write cache with FUA writes
2) Normal write without a volatile write cache

Rename that flag to IOMAP_DIO_STABLE_WRITE to make that clearer, and
update some of the FUA comments as well.

Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-08-01 17:32:35 -06:00
Jens Axboe
44842f6473 iomap: use an unsigned type for IOMAP_DIO_* defines
IOMAP_DIO_DIRTY shifts by 31 bits, which makes UBSAN unhappy. Clean up
all the defines by making the shifted value an unsigned value.

Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reported-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-08-01 17:32:32 -06:00
Jens Axboe
3486237c6f iomap: cleanup up iomap_dio_bio_end_io()
Make the logic a bit easier to follow:

1) Add a release_bio out path, as everybody needs to touch that, and
   have our bio ref check jump there if it's non-zero.
2) Add a kiocb local variable.
3) Add comments for each of the three conditions (sync, inline, or
   async workqueue punt).

No functional changes in this patch.

Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-08-01 17:32:17 -06:00
Ritesh Harjani (IBM)
4ce02c6797 iomap: Add per-block dirty state tracking to improve performance
When filesystem blocksize is less than folio size (either with
mapping_large_folio_support() or with blocksize < pagesize) and when the
folio is uptodate in pagecache, then even a byte write can cause
an entire folio to be written to disk during writeback. This happens
because we currently don't have a mechanism to track per-block dirty
state within struct iomap_folio_state. We currently only track uptodate
state.

This patch implements support for tracking per-block dirty state in
iomap_folio_state->state bitmap. This should help improve the filesystem
write performance and help reduce write amplification.

Performance testing of below fio workload reveals ~16x performance
improvement using nvme with XFS (4k blocksize) on Power (64K pagesize)
FIO reported write bw scores improved from around ~28 MBps to ~452 MBps.

1. <test_randwrite.fio>
[global]
	ioengine=psync
	rw=randwrite
	overwrite=1
	pre_read=1
	direct=0
	bs=4k
	size=1G
	dir=./
	numjobs=8
	fdatasync=1
	runtime=60
	iodepth=64
	group_reporting=1

[fio-run]

2. Also our internal performance team reported that this patch improves
   their database workload performance by around ~83% (with XFS on Power)

Reported-by: Aravinda Herle <araherle@in.ibm.com>
Reported-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2023-07-25 10:55:56 +05:30
Ritesh Harjani (IBM)
a01b8f2252 iomap: Allocate ifs in ->write_begin() early
We dont need to allocate an ifs in ->write_begin() for writes where the
position and length completely overlap with the given folio.
Therefore, such cases are skipped.

Currently when the folio is uptodate, we only allocate ifs at writeback
time (in iomap_writepage_map()). This is ok until now, but when we are
going to add support for per-block dirty state bitmap in ifs, this
could cause some performance degradation. The reason is that if we don't
allocate ifs during ->write_begin(), then we will never mark the
necessary dirty bits in ->write_end() call. And we will have to mark all
the bits as dirty at the writeback time, that could cause the same write
amplification and performance problems as it is now.

Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2023-07-25 10:55:56 +05:30
Ritesh Harjani (IBM)
7f79d85b52 iomap: Refactor iomap_write_delalloc_punch() function out
This patch factors iomap_write_delalloc_punch() function out. This function
is resposible for actual punch out operation.
The reason for doing this is, to avoid deep indentation when we bring
punch-out of individual non-dirty blocks within a dirty folio in a later
patch (which adds per-block dirty status handling to iomap) to avoid
delalloc block leak.

Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2023-07-25 10:55:56 +05:30