linux-stable.git/block/bio.c, branch v6.14

block: fix 'kmem_cache of name 'bio-108' already exists'

2025-02-28T14:06:42+00:00

Device mapper bioset often has big bio_slab size, which can be more than
1000, then 8byte can't hold the slab name any more, cause the kmem_cache
allocation warning of 'kmem_cache of name 'bio-108' already exists'.

Fix the warning by extending bio_slab->name to 12 bytes, but fix output
of /proc/slabinfo

Reported-by: Guangwu Zhang 
Signed-off-by: Ming Lei 
Link: https://lore.kernel.org/r/20250228132656.2838008-1-ming.lei@redhat.com
Signed-off-by: Jens Axboe

block: Don't trim an atomic write

2025-01-17T20:13:55+00:00

This is disallowed.

This check will now be relevant since the device mapper personalities
will start to support atomic writes, and they use this function.

Signed-off-by: John Garry 
Reviewed-by: Mike Snitzer 
Link: https://lore.kernel.org/r/20250116170301.474130-3-john.g.garry@oracle.com
Signed-off-by: Jens Axboe

block: remove bio_add_pc_page

2025-01-04T22:27:35+00:00

Lift bio_split_rw_at into blk_rq_append_bio so that it validates the
hardware limits.  With this all passthrough callers can simply add
bio_add_page to build the bio and delay checking for exceeding of limits
to this point instead of doing it for each page.

While this looks like adding a new expensive loop over all bio_vecs,
blk_rq_append_bio is already doing that just to counter the number of
segments.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Sagi Grimberg 
Link: https://lore.kernel.org/r/20250103073417.459715-2-hch@lst.de
Signed-off-by: Jens Axboe

block: Make bio_iov_bvec_set() accept pointer to const iov_iter

2024-12-12T15:43:28+00:00

Make bio_iov_bvec_set() accept a pointer to const iov_iter, which means
that we can drop the undesirable casting to struct iov_iter pointer in
blk_rq_map_user_bvec().

Signed-off-by: John Garry 
Reviewed-by: Christoph Hellwig 
Link: https://lore.kernel.org/r/20241202115727.2320401-1-john.g.garry@oracle.com
Signed-off-by: Jens Axboe

block: Error an attempt to split an atomic write in bio_split()

2024-11-11T15:35:46+00:00

This is disallowed.

Reviewed-by: Christoph Hellwig 
Reviewed-by: Johannes Thumshirn 
Reviewed-by: Hannes Reinecke 
Signed-off-by: John Garry 
Link: https://lore.kernel.org/r/20241111112150.3756529-3-john.g.garry@oracle.com
Signed-off-by: Jens Axboe

block: Rework bio_split() return value

2024-11-11T15:35:46+00:00

Instead of returning an inconclusive value of NULL for an error in calling
bio_split(), return a ERR_PTR() always.

Also remove the BUG_ON() calls, and WARN_ON_ONCE() instead. Indeed, since
almost all callers don't check the return code from bio_split(), we'll
crash anyway (for those failures).

Fix up the only user which checks bio_split() return code today (directly
or indirectly), blk_crypto_fallback_split_bio_if_needed(). The md/bcache
code does check the return code in cached_dev_cache_miss() ->
bio_next_split() -> bio_split(), but only to see if there was a split, so
there would be no change in behaviour here (when returning a ERR_PTR()).

Reviewed-by: Christoph Hellwig 
Reviewed-by: Johannes Thumshirn 
Signed-off-by: John Garry 
Link: https://lore.kernel.org/r/20241111112150.3756529-2-john.g.garry@oracle.com
Signed-off-by: Jens Axboe

block: remove bio_add_zone_append_page

2024-10-31T16:54:25+00:00

This is only used by the nvmet zns passthrough code, which can trivially
just use bio_add_pc_page and do the sanity check for the max zone append
limit itself.

All future zoned file systems should follow the btrfs lead and let the
upper layers fill up bios unlimited by hardware constraints and split
them to the limits in the I/O submission handler.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Chaitanya Kulkarni 
Link: https://lore.kernel.org/r/20241030051859.280923-3-hch@lst.de
Signed-off-by: Jens Axboe

block: remove zone append special casing from the direct I/O path

2024-10-31T16:54:25+00:00

This code is unused, and all future zoned file systems should follow
the btrfs lead of splitting the bios themselves to the zoned limits
in the I/O submission handler, because if they didn't they would be
hit by commit ed9832bc08db ("block: introduce folio awareness and add
a bigger size from folio") breaking this code when the zone append
limit (that is usually the max_hw_sectors limit) is smaller than the
largest possible folio size.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Chaitanya Kulkarni 
Link: https://lore.kernel.org/r/20241030051859.280923-2-hch@lst.de
Signed-off-by: Jens Axboe

block: unpin user pages belonging to a folio at once

2024-09-11T13:24:01+00:00

Use newly added mm function unpin_user_folio() to put refs by npages
count.

Signed-off-by: Kundan Kumar 
Tested-by: Luis Chamberlain 
Link: https://lore.kernel.org/r/20240911064935.5630-5-kundan.kumar@samsung.com
Signed-off-by: Jens Axboe

block: introduce folio awareness and add a bigger size from folio

2024-09-11T13:24:01+00:00

Add a bigger size from folio to bio and skip merge processing for pages.

Fetch the offset of page within a folio. Depending on the size of folio
and folio_offset, fetch a larger length. This length may consist of
multiple contiguous pages if folio is multiorder.

Using the length calculate number of pages which will be added to bio and
increment the loop counter to skip those pages.

This technique helps to avoid overhead of merging pages which belong to
same large order folio.

Also folio-ize the functions bio_iov_add_page() and
bio_iov_add_zone_append_page()

Signed-off-by: Kundan Kumar 
Tested-by: Luis Chamberlain 
Reviewed-by: Christoph Hellwig 
Reviewed-by: Matthew Wilcox (Oracle) 
Link: https://lore.kernel.org/r/20240911064935.5630-3-kundan.kumar@samsung.com
Signed-off-by: Jens Axboe