block: don't autoload drivers on stat

blkdev_get_no_open can trigger the legacy autoload of block drivers. A
simple stat of a block device has not historically done that, so disable
this behavior a

block: don't autoload drivers on stat

blkdev_get_no_open can trigger the legacy autoload of block drivers. A
simple stat of a block device has not historically done that, so disable
this behavior again.

Fixes: 9abcfbd235f5 ("block: Add atomic write support for statx")
Signed-off-by: Christoph Hellwig <[email protected]>
Reviewed-by: Christian Brauner <[email protected]>
Acked-by: Tejun Heo <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jens Axboe <[email protected]>

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block: fix race between set_blocksize and read paths

With the new large sector size support, it's now the case that
set_blocksize can change i_blksize and the folio order in a manner that
conflicts

block: fix race between set_blocksize and read paths

With the new large sector size support, it's now the case that
set_blocksize can change i_blksize and the folio order in a manner that
conflicts with a concurrent reader and causes a kernel crash.

Specifically, let's say that udev-worker calls libblkid to detect the
labels on a block device. The read call can create an order-0 folio to
read the first 4096 bytes from the disk. But then udev is preempted.

Next, someone tries to mount an 8k-sectorsize filesystem from the same
block device. The filesystem calls set_blksize, which sets i_blksize to
8192 and the minimum folio order to 1.

Now udev resumes, still holding the order-0 folio it allocated. It then
tries to schedule a read bio and do_mpage_readahead tries to create
bufferheads for the folio. Unfortunately, blocks_per_folio == 0 because
the page size is 4096 but the blocksize is 8192 so no bufferheads are
attached and the bh walk never sets bdev. We then submit the bio with a
NULL block device and crash.

Therefore, truncate the page cache after flushing but before updating
i_blksize. However, that's not enough -- we also need to lock out file
IO and page faults during the update. Take both the i_rwsem and the
invalidate_lock in exclusive mode for invalidations, and in shared mode
for read/write operations.

I don't know if this is the correct fix, but xfs/259 found it.

Signed-off-by: Darrick J. Wong <[email protected]>
Reviewed-by: Christoph Hellwig <[email protected]>
Reviewed-by: Luis Chamberlain <[email protected]>
Tested-by: Shin'ichiro Kawasaki <[email protected]>
Link: https://lore.kernel.org/r/174543795699.4139148.2086129139322431423.stgit@frogsfrogsfrogs
Signed-off-by: Jens Axboe <[email protected]>

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block: don't revert iter for -EIOCBQUEUED

blkdev_read_iter() has a few odd checks, like gating the position and
count adjustment on whether or not the result is bigger-than-or-equal to
zero (where b

block: don't revert iter for -EIOCBQUEUED

blkdev_read_iter() has a few odd checks, like gating the position and
count adjustment on whether or not the result is bigger-than-or-equal to
zero (where bigger than makes more sense), and not checking the return
value of blkdev_direct_IO() before doing an iov_iter_revert(). The
latter can lead to attempting to revert with a negative value, which
when passed to iov_iter_revert() as an unsigned value will lead to
throwing a WARN_ON() because unroll is bigger than MAX_RW_COUNT.

Be sane and don't revert for -EIOCBQUEUED, like what is done in other
spots.

Cc: [email protected]
Signed-off-by: Jens Axboe <[email protected]>

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block: add support to pass user meta buffer

If an iocb contains metadata, extract that and prepare the bip.
Based on flags specified by the user, set corresponding guard/app/ref
tags to be checked i

block: add support to pass user meta buffer

If an iocb contains metadata, extract that and prepare the bip.
Based on flags specified by the user, set corresponding guard/app/ref
tags to be checked in bip.

Reviewed-by: Christoph Hellwig <[email protected]>
Signed-off-by: Anuj Gupta <[email protected]>
Signed-off-by: Kanchan Joshi <[email protected]>
Reviewed-by: Keith Busch <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jens Axboe <[email protected]>

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block: Don't allow an atomic write be truncated in blkdev_write_iter()

A write which goes past the end of the bdev in blkdev_write_iter() will
be truncated. Truncating cannot tolerated for an atomic

block: Don't allow an atomic write be truncated in blkdev_write_iter()

A write which goes past the end of the bdev in blkdev_write_iter() will
be truncated. Truncating cannot tolerated for an atomic write, so error
that condition.

Fixes: caf336f81b3a ("block: Add fops atomic write support")
Signed-off-by: John Garry <[email protected]>
Reviewed-by: Christoph Hellwig <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jens Axboe <[email protected]>

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fs/block: Check for IOCB_DIRECT in generic_atomic_write_valid()

Currently FMODE_CAN_ATOMIC_WRITE is set if the bdev can atomic write and
the file is open for direct IO. This does not work if the fil

fs/block: Check for IOCB_DIRECT in generic_atomic_write_valid()

Currently FMODE_CAN_ATOMIC_WRITE is set if the bdev can atomic write and
the file is open for direct IO. This does not work if the file is not
opened for direct IO, yet fcntl(O_DIRECT) is used on the fd later.

Change to check for direct IO on a per-IO basis in
generic_atomic_write_valid(). Since we want to report -EOPNOTSUPP for
non-direct IO for an atomic write, change to return an error code.

Relocate the block fops atomic write checks to the common write path, as to
catch non-direct IO.

Fixes: c34fc6f26ab8 ("fs: Initial atomic write support")
Reviewed-by: Christoph Hellwig <[email protected]>
Reviewed-by: Darrick J. Wong <[email protected]>
Signed-off-by: John Garry <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jens Axboe <[email protected]>

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block/fs: Pass an iocb to generic_atomic_write_valid()

Darrick and Hannes both thought it better that generic_atomic_write_valid()
should be passed a struct iocb, and not just the member of that str

block/fs: Pass an iocb to generic_atomic_write_valid()

Darrick and Hannes both thought it better that generic_atomic_write_valid()
should be passed a struct iocb, and not just the member of that struct
which is referenced; see [0] and [1].

I think that makes a more generic and clean API, so make that change.

[0] https://lore.kernel.org/linux-block/[email protected]/
[1] https://lore.kernel.org/linux-xfs/20240620212401.GA3058325@frogsfrogsfrogs/

Fixes: c34fc6f26ab8 ("fs: Initial atomic write support")
Suggested-by: Darrick J. Wong <[email protected]>
Suggested-by: Hannes Reinecke <[email protected]>
Reviewed-by: Darrick J. Wong <[email protected]>
Reviewed-by: Christoph Hellwig <[email protected]>
Signed-off-by: John Garry <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jens Axboe <[email protected]>

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block: implement async io_uring discard cmd

io_uring allows implementing custom file specific asynchronous
operations via the fops->uring_cmd callback, a.k.a. IORING_OP_URING_CMD
requests or just io

block: implement async io_uring discard cmd

io_uring allows implementing custom file specific asynchronous
operations via the fops->uring_cmd callback, a.k.a. IORING_OP_URING_CMD
requests or just io_uring commands. Use it to add support for async
discards.

Normally, it first tries to queue up bios in a non-blocking context,
and if that fails, we'd retry from a blocking context by returning
-EAGAIN to the core io_uring. We always get the result from bios
asynchronously by setting a custom bi_end_io callback, at which point
we drag the request into the task context to either reissue or complete
it and post a completion to the user.

Unlike ioctl(BLKDISCARD) with stronger guarantees against races, we only
do a best effort attempt to invalidate page cache, and it can race with
any writes and reads and leave page cache stale. It's the same kind of
races we allow to direct writes.

Also, apart from cases where discarding is not allowed at all, e.g.
discards are not supported or the file/device is read only, the user
should assume that the sector range on disk is not valid anymore, even
when an error was returned to the user.

Suggested-by: Conrad Meyer <[email protected]>
Signed-off-by: Pavel Begunkov <[email protected]>
Link: https://lore.kernel.org/r/2b5210443e4fa0257934f73dfafcc18a77cd0e09.1726072086.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <[email protected]>

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iomap: add a private argument for iomap_file_buffered_write

In order to switch fuse over to using iomap for buffered writes we need
to be able to have the struct file for the original write, in case

iomap: add a private argument for iomap_file_buffered_write

In order to switch fuse over to using iomap for buffered writes we need
to be able to have the struct file for the original write, in case we
have to read in the page to make it uptodate. Handle this by using the
existing private field in the iomap_iter, and add the argument to
iomap_file_buffered_write. This will allow us to pass the file in
through the iomap buffered write path, and is flexible for any other
file systems needs.

Signed-off-by: Josef Bacik <[email protected]>
Link: https://lore.kernel.org/r/7f55c7c32275004ba00cddf862d970e6e633f750.1724755651.git.josef@toxicpanda.com
Reviewed-by: Christoph Hellwig <[email protected]>
Signed-off-by: Christian Brauner <[email protected]>

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block: remove checks for FALLOC_FL_NO_HIDE_STALE

While the FALLOC_FL_NO_HIDE_STALE value has been registered, it has
always been rejected by vfs_fallocate before making it into
blkdev_fallocate beca

block: remove checks for FALLOC_FL_NO_HIDE_STALE

While the FALLOC_FL_NO_HIDE_STALE value has been registered, it has
always been rejected by vfs_fallocate before making it into
blkdev_fallocate because it isn't in the supported mask.

Signed-off-by: Christoph Hellwig <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Reviewed-by: Darrick J. Wong <[email protected]>
Reviewed-by: Jan Kara <[email protected]>
Signed-off-by: Christian Brauner <[email protected]>

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fs: Convert aops->write_begin to take a folio

Convert all callers from working on a page to working on one page
of a folio (support for working on an entire folio can come later).
Removes a lot of f

fs: Convert aops->write_begin to take a folio

Convert all callers from working on a page to working on one page
of a folio (support for working on an entire folio can come later).
Removes a lot of folio->page->folio conversions.

Reviewed-by: Josef Bacik <[email protected]>
Signed-off-by: Matthew Wilcox (Oracle) <[email protected]>
Signed-off-by: Christian Brauner <[email protected]>

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fs: Convert aops->write_end to take a folio

Most callers have a folio, and most implementations operate on a folio,
so remove the conversion from folio->page->folio to fit through this
interface.

R

fs: Convert aops->write_end to take a folio

Most callers have a folio, and most implementations operate on a folio,
so remove the conversion from folio->page->folio to fit through this
interface.

Reviewed-by: Josef Bacik <[email protected]>
Signed-off-by: Matthew Wilcox (Oracle) <[email protected]>
Signed-off-by: Christian Brauner <[email protected]>

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buffer: Convert block_write_end() to take a folio

All callers now have a folio, so pass it in instead of converting
from a folio to a page and back to a folio again. Saves a call
to compound_head()

buffer: Convert block_write_end() to take a folio

All callers now have a folio, so pass it in instead of converting
from a folio to a page and back to a folio again. Saves a call
to compound_head().

Reviewed-by: Josef Bacik <[email protected]>
Signed-off-by: Matthew Wilcox (Oracle) <[email protected]>
Signed-off-by: Christian Brauner <[email protected]>

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block: Use a folio in blkdev_write_end()

Replaces two hidden calls to compound_head() with one explicit one.

Reviewed-by: Josef Bacik <[email protected]>
Signed-off-by: Matthew Wilcox (Oracle) <

block: Use a folio in blkdev_write_end()

Replaces two hidden calls to compound_head() with one explicit one.

Reviewed-by: Josef Bacik <[email protected]>
Signed-off-by: Matthew Wilcox (Oracle) <[email protected]>
Signed-off-by: Christian Brauner <[email protected]>

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block: clean up the check in blkdev_iomap_begin()

It is odd to check the offset amidst a series of assignments. Moving this
check to the beginning of the function makes the code look better.

Signed

block: clean up the check in blkdev_iomap_begin()

It is odd to check the offset amidst a series of assignments. Moving this
check to the beginning of the function makes the code look better.

Signed-off-by: Li Nan <[email protected]>
Reviewed-by: Chaitanya Kulkarni <[email protected]>
Reviewed-by: Christoph Hellwig <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jens Axboe <[email protected]>

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block: Add fops atomic write support

Support atomic writes by submitting a single BIO with the REQ_ATOMIC set.

It must be ensured that the atomic write adheres to its rules, like
naturally aligned

block: Add fops atomic write support

Support atomic writes by submitting a single BIO with the REQ_ATOMIC set.

It must be ensured that the atomic write adheres to its rules, like
naturally aligned offset, so call blkdev_dio_invalid() ->
blkdev_atomic_write_valid() [with renaming blkdev_dio_unaligned() to
blkdev_dio_invalid()] for this purpose. The BIO submission path currently
checks for atomic writes which are too large, so no need to check here.

In blkdev_direct_IO(), if the nr_pages exceeds BIO_MAX_VECS, then we cannot
produce a single BIO, so error in this case.

Finally set FMODE_CAN_ATOMIC_WRITE when the bdev can support atomic writes
and the associated file flag is for O_DIRECT.

Reviewed-by: Martin K. Petersen <[email protected]>
Signed-off-by: John Garry <[email protected]>
Reviewed-by: Keith Busch <[email protected]>
Acked-by: Darrick J. Wong <[email protected]>
Reviewed-by: Darrick J. Wong <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jens Axboe <[email protected]>

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block: refine the EOF check in blkdev_iomap_begin

blkdev_iomap_begin rounds down the offset to the logical block size
before stashing it in iomap->offset and checking that it still is
inside the ino

block: refine the EOF check in blkdev_iomap_begin

blkdev_iomap_begin rounds down the offset to the logical block size
before stashing it in iomap->offset and checking that it still is
inside the inode size.

Check the i_size check to the raw pos value so that we don't try a
zero size write if iter->pos is unaligned.

Fixes: 487c607df790 ("block: use iomap for writes to block devices")
Reported-by: [email protected]
Signed-off-by: Christoph Hellwig <[email protected]>
Tested-by: [email protected]
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jens Axboe <[email protected]>

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blkdev_write_iter(): saner way to get inode and bdev

... same as in other methods - bdev_file_inode() and I_BDEV() of that.

Signed-off-by: Al Viro <[email protected]>
Link: https://lore.kerne

blkdev_write_iter(): saner way to get inode and bdev

... same as in other methods - bdev_file_inode() and I_BDEV() of that.

Signed-off-by: Al Viro <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Christian Brauner <[email protected]>

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block: Call blkdev_dio_unaligned() from blkdev_direct_IO()

blkdev_dio_unaligned() is called from __blkdev_direct_IO(),
__blkdev_direct_IO_simple(), and __blkdev_direct_IO_async(), and all these
are

block: Call blkdev_dio_unaligned() from blkdev_direct_IO()

blkdev_dio_unaligned() is called from __blkdev_direct_IO(),
__blkdev_direct_IO_simple(), and __blkdev_direct_IO_async(), and all these
are only called from blkdev_direct_IO().

Move the blkdev_dio_unaligned() call to the common callsite,
blkdev_direct_IO().

Pass those functions the bdev pointer from blkdev_direct_IO(), as it is
non-trivial to look up.

Reviewed-by: Keith Busch <[email protected]>
Reviewed-by: Christoph Hellwig <[email protected]>
Reviewed-by: Luis Chamberlain <[email protected]>
Signed-off-by: John Garry <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jens Axboe <[email protected]>

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fs: claw back a few FMODE_* bits

There's a bunch of flags that are purely based on what the file
operations support while also never being conditionally set or unset.
IOW, they're not subject to cha

fs: claw back a few FMODE_* bits

There's a bunch of flags that are purely based on what the file
operations support while also never being conditionally set or unset.
IOW, they're not subject to change for individual files. Imho, such
flags don't need to live in f_mode they might as well live in the fops
structs itself. And the fops struct already has that lonely
mmap_supported_flags member. We might as well turn that into a generic
fop_flags member and move a few flags from FMODE_* space into FOP_*
space. That gets us four FMODE_* bits back and the ability for new
static flags that are about file ops to not have to live in FMODE_*
space but in their own FOP_* space. It's not the most beautiful thing
ever but it gets the job done. Yes, there'll be an additional pointer
chase but hopefully that won't matter for these flags.

I suspect there's a few more we can move into there and that we can also
redirect a bunch of new flag suggestions that follow this pattern into
the fop_flags field instead of f_mode.

Link: https://lore.kernel.org/r/20240328-gewendet-spargel-aa60a030ef74@brauner
Reviewed-by: Christoph Hellwig <[email protected]>
Reviewed-by: Jan Kara <[email protected]>
Reviewed-by: Jens Axboe <[email protected]>
Signed-off-by: Christian Brauner <[email protected]>

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block: remove bdev_handle completely

We just need to use the holder to indicate whether a block device open
was exclusive or not. We did use to do that before but had to give that
up once we switche

block: remove bdev_handle completely

We just need to use the holder to indicate whether a block device open
was exclusive or not. We did use to do that before but had to give that
up once we switched to struct bdev_handle. Before struct bdev_handle we
only stashed stuff in file->private_data if this was an exclusive open
but after struct bdev_handle we always set file->private_data to a
struct bdev_handle and so we had to use bdev_handle->mode or
bdev_handle->holder. Now that we don't use struct bdev_handle anymore we
can revert back to the old behavior.

Link: https://lore.kernel.org/r/[email protected]
Reviewed-by: Christoph Hellwig <[email protected]>
Signed-off-by: Christian Brauner <[email protected]>

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bdev: remove bdev pointer from struct bdev_handle

We can always go directly via:

* I_BDEV(bdev_file->f_inode)
* I_BDEV(bdev_file->f_mapping->host)

So keeping struct bdev in struct bdev_handle is r

bdev: remove bdev pointer from struct bdev_handle

We can always go directly via:

* I_BDEV(bdev_file->f_inode)
* I_BDEV(bdev_file->f_mapping->host)

So keeping struct bdev in struct bdev_handle is redundant.

Link: https://lore.kernel.org/r/[email protected]
Reviewed-by: Christoph Hellwig <[email protected]>
Reviewed-by: Jan Kara <[email protected]>
Signed-off-by: Christian Brauner <[email protected]>

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bdev: make struct bdev_handle private to the block layer

Link: https://lore.kernel.org/r/[email protected]
Reviewed-by: Christoph Hellwig <[email protected]>
Signed-off-b

bdev: make struct bdev_handle private to the block layer

Link: https://lore.kernel.org/r/[email protected]
Reviewed-by: Christoph Hellwig <[email protected]>
Signed-off-by: Christian Brauner <[email protected]>

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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 b179c98f7697 ("block: R

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 b179c98f7697 ("block: Remove
request.write_hint") and commit c75e707fe1aa ("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 <[email protected]>
Cc: Jens Axboe <[email protected]>
Cc: Christoph Hellwig <[email protected]>
Signed-off-by: Bart Van Assche <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Christian Brauner <[email protected]>

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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 spac

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 <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Christian Brauner <[email protected]>

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