100 Commits
Author SHA1 Message Date
Keith Busch 5cdd07a688 MAINTAINERS: update nvme entry
Update Jens' entry to match the mail address of his other entries.

Acked-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Keith Busch <kbusch@kernel.org>
2026-09-03 14:15:10 -07:00
Keith Busch e52349a5ea loop, zloop: fix dma_alignment for large or unreported limits
A file system sets STATX_DIOALIGN with zeroed alignments when the file
can't be used for direct I/O. The zero underflowed to UINT_MAX and
triggered a queue limits validation warning. Fall back to the block
device's limits when dio_mem_align isn't reported.

A file system with a block size larger than PAGE_SIZE may also report a
memory alignment that can't be expressed as a queue limit. File systems
fall back to buffered I/O for requests that don't meet their alignment,
so cap the reported limit to the largest possible value.

Fixes: 6c8dec275c ("loop: set dma_alignment from the backing file for direct I/O")
Fixes: c5059c1af2 ("zloop: set dma_alignment from the backing files for direct I/O")
Reported-by: syzbot+ac00e7bf7ac8c91af921@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=ac00e7bf7ac8c91af921
Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://patch.msgid.link/20260810164218.3721636-1-kbusch@meta.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-09-01 08:42:54 -06:00
Keith Busch 96c8ea3c5a block: save page offset gaps in cloned bio
The cloned bio needs to inherit the accumulated gaps between vectors so
that we can know if this bio can subscribe to the iova coalescing
optimization.

When cloning for a split, the gap only applies to the front bio since
that's as far as has been processed. The remaining bio can reset its
gaps to 0 since it advanced past the checked vectors, and will start its
accounting from there on the next split check.

Fixes: 2f6b2565d4 ("block: accumulate memory segment gaps per bio")
Reported-by: Eric Auger <eauger@redhat.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://patch.msgid.link/20260819154937.3903312-1-kbusch@meta.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-09-01 08:42:34 -06:00
Keith Busch 14b007e178 block: validate user space vectors during extraction
The bio-based drivers don't necessarily check the alignment split, and
stacking block drivers don't always handle a misalignment detected after
submitting the bio. Validate user vectors against the device's
dma_alignment as the bio is built from the iov_iter, rejecting
misaligned early with -EINVAL.

Cc: stable@vger.kernel.org
Fixes: 5ff3f74e14 ("block: simplify direct io validity check")
Fixes: 7eac331869 ("iomap: simplify direct io validity check")
Reviewed-by: Hannes Reinecke <hare@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Link: https://patch.msgid.link/20260720201057.1862857-6-kbusch@meta.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-07-31 08:10:49 -06:00
Keith Busch c5059c1af2 zloop: set dma_alignment from the backing files for direct I/O
Direct I/O request's use pages handed to the backing files unchanged, so
the backing's DMA alignment requirement applies. Track dio_mem_align and
advertise it as the device's dma_alignment so we communicate proper
limits and misaligned I/O is rejected here instead of reaching the
backend.

Reviewed-by: Hannes Reinecke <hare@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Link: https://patch.msgid.link/20260720201057.1862857-5-kbusch@meta.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-07-30 15:54:07 -06:00
Keith Busch 6c8dec275c loop: set dma_alignment from the backing file for direct I/O
Direct I/O user pages are forwarded to the backing file unchanged, so
the backing's DMA alignment requirement applies to them. Track the
backing's dio_mem_align and advertise it as the loop device's
dma_alignment so we advertise proper limits and misaligned I/O is
rejected here instead of being dispatched to the backend.

Reviewed-by: Hannes Reinecke <hare@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Link: https://patch.msgid.link/20260720201057.1862857-4-kbusch@meta.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-07-30 15:54:07 -06:00
Keith Busch 702a2a9f3d block: fix dio leak on metadata mapping error
A failed integrity mapping holds a dio reference, so we need to go
through the full bio ending in case there were previously submitted
bio's in the sequence.

Fixes: 2729a60bbf ("block: don't silently ignore metadata for sync read/write")
Reviewed-by: Hannes Reinecke <hare@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Link: https://patch.msgid.link/20260720201057.1862857-3-kbusch@meta.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-07-30 15:54:07 -06:00
Keith Busch 75ae18ca94 block: use blkdev_iov_iter_get_pages status for errors
blkdev_iov_iter_get_pages() can return various error values, including
EIO, EFAULT, and ENOMEM. Set the actual reported status so user space
can know why an operation failed.

Reviewed-by: Hannes Reinecke <hare@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Link: https://patch.msgid.link/20260720201057.1862857-2-kbusch@meta.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-07-30 15:54:06 -06:00
Keith Busch 62dc37a819 dm-io: clone the source bio instead of copying its biovec
For DM_IO_BIO requests, do_region() built each destination bio by walking
the source bio's biovec and re-adding the pages one at a time, tracking
the remaining transfer in sectors. The vector lengths are byte granular
and need not be sector aligned (e.g. a misaligned O_DIRECT buffer split
across pages), so the sector-based accounting could lose a sub-sector
fragment: to_sector() truncated the remainder and the outer loop spun
forever submitting empty bios, hanging the I/O.

There is no need to rebuild the biovec at all. The destination reads into
(or writes from) exactly the same pages as the source bio, so the bio can
simply clone the source's biovec with bio_alloc_clone() and remap it to
the target device. The clone inherits the source's iterator and alignment,
and the block layer splits it to the target's limits on submission, so the
whole region maps to a single cloned bio with no manual page copying or
sector accounting.

This removes the per-page copy path (and its open-coded bvec dpages
helpers) for bio-backed I/O and fixes the hang on misaligned direct I/O to
a dm-mirror device. Page-list, vma and kmem sources keep the existing copy
path.

Fixes: 7eac331869 ("iomap: simplify direct io validity check")
Fixes: 5ff3f74e14 ("block: simplify direct io validity check")
Cc: stable@vger.kernel.org
Reported-by: Dr. David Alan Gilbert <linux@treblig.org>
Reported-by: Vjaceslavs Klimovs <vklimovs@gmail.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
2026-07-27 23:08:38 +02:00
Keith Busch 9b0c3673c8 block: check bio split for unaligned bvec
Offsets and lengths need to be validated against the dma alignment. This
check was skipped for sufficiently a small bio with a single bvec, which
may allow an invalid request dispatched to the driver. Force the
validation for an unaligned bvec by forcing the bio split path that
handles this condition.

Fixes: 7eac331869 ("iomap: simplify direct io validity check")
Fixes: 5ff3f74e14 ("block: simplify direct io validity check")
Reported-by: Carlos Maiolino <cem@kernel.org>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Link: https://patch.msgid.link/20260612223205.465913-1-kbusch@meta.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-06-13 06:35:44 -06:00
Keith Busch 7d6eb455ec nvme: add support multipath passthrough iostats
Don't skip the io accounting for passthrough commands if the user
enabled tracking these.

Reviewed-by: Nilay Shroff <nilay@linux.ibm.com>
Reviewed-by: Nitesh Shetty <nj.shetty@samsung.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://patch.msgid.link/20260528010041.1533124-3-kbusch@meta.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-05-28 09:35:38 -06:00
Keith Busch b7f40ab501 block: export passthrough stats enabled
A user can enable io accounting for passthrough requests, so export the
helper that checks if the request should be tracked. This will enable
stacking drivers to to report iostats for passthrough workloads. Since
the stacking request_queue may not be the one providing the request, the
API has to add a parameter for the caller to specify which one to check.

Reviewed-by: Nilay Shroff <nilay@linux.ibm.com>
Reviewed-by: Nitesh Shetty <nj.shetty@samsung.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://patch.msgid.link/20260528010041.1533124-2-kbusch@meta.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-05-28 09:35:38 -06:00
Keith Busch b051bb6bf0 blk-mq: reinsert cached request to the list
A previous commit removed an optimization out of caution for a scenario
that turns out not to be real: all the "queue_exit" goto's are safe to
reinsert the request into the cached_rq's plug list as they are either
from a non-blocking path, or a successful merge that already holds the
queue reference. This optimization is most needed for small sequential
workloads that successfully merge into larger requests.

Fixes: dc278e9bf2 ("blk-mq: pop cached request if it is usable")
Suggested-by: Ming Lei <tom.leiming@gmail.com>
Suggested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://patch.msgid.link/20260526153531.2365935-1-kbusch@meta.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-05-26 15:05:30 -06:00
Keith Busch dc278e9bf2 blk-mq: pop cached request if it is usable
When submitting a bio to blk-mq, if the task should sleep after peeking
a cached request, but before it pops it, the plug flushes and calls
blk_mq_free_plug_rqs, freeing the cached_rqs. This creates a
use-after-free bug. Fix this by popping the cached request before any
possible blocking calls if it is suitable for use.

Popping this request first holds a queue reference, so avoid any
serialization races with queue freezes and can safely proceed with
dispatching that request to the driver. This potentially increases a
timing window from when a driver wants to freeze its queue to when
requests stop being dispatched. That scenario is off the fast path
though, and drivers need to appropriately handle requests during a
freeze request anyway.

The downside is the popped element needs to be individually freed when
we performed a bio plug merge. The cached request would have had to be
freed later anyway, but this patch does it inline with building the plug
list instead of after flushing it.

Fixes: b0077e269f ("blk-mq: make sure active queue usage is held for bio_integrity_prep()")
Fixes: 7b4f36cd22 ("block: ensure we hold a queue reference when using queue limits")
Signed-off-by: Keith Busch <kbusch@kernel.org>
Link: https://patch.msgid.link/20260521190253.242065-1-kbusch@meta.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-05-21 13:04:11 -06:00
Keith Busch 1bf86336e4 nvme-pci: fix dma mapping leak on data setup error
We're leaking the initial DMA mapping during iteration if we fail to
allocate the tracking descriptor for both PRP and SGL. Unmap the
iterator directly; we can't use the existing unmap helper because it
depends on the tracking descriptor being successfully allocated, so a
new one for an in-use iterator is provided.

The mappings were also leaking when the driver detects an invalid
bio_vec when mapping PRPs, so fix that too.

Fixes: b8b7570a7e ("nvme-pci: fix dma unmapping when using PRPs and not using the IOVA mapping")
Fixes: 7ce3c1dd78 ("nvme-pci: convert the data mapping to blk_rq_dma_map")
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>
2026-05-21 07:49:05 -07:00
Keith Busch 85686c7296 nvme-pci: fix dma_vecs leak on p2p memory
We don't unmap P2P memory, so we don't need to track it. The dma_vec
allocation was getting leaked on the completion.

Fixes: b8b7570a7e ("nvme-pci: fix dma unmapping when using PRPs and not using the IOVA mapping")
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>
2026-05-21 07:48:58 -07:00
Keith Busch 2279cd9c61 nvme: fix bio leak on mapping failure
The local bio is always NULL, so we'd leak the bio if the integrity
mapping failed. Just get it directly from the request.

Fixes: d0d1d52231 ("blk-map: provide the bdev to bio if one exists")
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>
2026-05-11 08:07:39 -07:00
Keith Busch ce28b772c3 nvme: make prp passthrough usage less scary
The warning is a bit alarming, and it only prints for the very first
non-sgl capable device that receives a passthrough command. Just log an
informational message on initial discovery for every device.

Reviewed-by: Jens Axboe <axboe@kernel.dk>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>
2026-05-11 08:07:39 -07:00
Keith Busch f7b24c7b41 md/raid1,raid10: don't fail devices for invalid IO errors
BLK_STS_INVAL indicates the IO request itself was invalid, not that the
device has failed. When raid1 treats this as a device error, it retries
on alternate mirrors which fail the same way, eventually exceeding the
read error threshold and removing the device from the array.

This happens when stacking configurations bypass bio_split_to_limits()
in the IO path: dm-raid calls md_handle_request() directly without going
through md_submit_bio(), skipping the alignment validation that would
otherwise reject invalid bios early. The invalid bio reaches the
lower block layers, which fail the bio with  BLK_STS_INVAL, and raid1
wrongly interprets this as a device failure.

Add BLK_STS_INVAL to raid1_should_handle_error() so that invalid IO
errors are propagated back to the caller rather than triggering device
removal. This is consistent with the previous kernel behavior when
alignment checks were done earlier in the direct-io path.

Fixes: 5ff3f74e14 ("block: simplify direct io validity check")

Reported-by: Tomáš Trnka <trnka@scm.com>
Closes: https://lore.kernel.org/linux-block/2982107.4sosBPzcNG@electra/
Signed-off-by: Keith Busch <kbusch@kernel.org>
Tested-by: Tomáš Trnka <trnka@scm.com>
Link: https://lore.kernel.org/r/20260416140345.3872265-1-kbusch@meta.com
Signed-off-by: Yu Kuai <yukuai@fnnas.com>
2026-04-28 20:44:37 +08:00
Keith Busch cfcbfe5cb1 PCI: Don't fallback to bus reset after failed slot reset
If a bus has hotplug slots that implement the slot's reset_slot callback,
it is not safe to do the non-slot specific bus reset, so don't fallback to
it. If a slot reset does fail, the subsequent bus reset will attempt a 2nd
link reset on top of previous and fail to handle the hotplug events.

Fixes: 8238cb69c0 ("PCI: Make reset_subordinate hotplug safe")
Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Link: https://patch.msgid.link/20260421150644.3543733-1-kbusch@meta.com
2026-04-27 17:26:59 -05:00
Keith Busch 1cc4cdae2a nvme-pci: fix missed admin queue sq doorbell write
We can batch admin commands submitted through io_uring_cmd passthrough,
which means bd->last may be false and skips the doorbell write to
aggregate multiple commands per write. If a subsequent command can't be
dispatched for whatever reason, we have to provide the blk-mq ops'
commit_rqs callback in order to ensure we properly update the doorbell.

Fixes: 58e5bdeb9c ("nvme: enable uring-passthrough for admin commands")
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kanchan Joshi <joshi.k@samsung.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
2026-04-22 10:07:30 -07:00
Keith Busch bddb911d28 nvme: skip trace completion for host path errors
The command was never dispatched for the driver's "host path error", so
the command was never actually initialized and there's no corresponding
submit trace for the completion.

Reported-by: Minsik Jeon <hmi.jeon@samsung.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
2026-04-22 10:06:23 -07:00
Keith Busch 33eded2931 dm: provide helper to set stacked limits
There are multiple device mappers that set up their stacking limits
exactly the same for the logical, physical and minimum IO queue limits.
Provide a helper for it.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
2026-03-27 22:19:17 +01:00
Keith Busch cbc1532d2b dm-integrity: always set the io hints
Don't depend on the defaults to be what is desired if the integrity
device was set up with 512b sector size. Always set the queue limits to
be at least what the device mapper wants.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
2026-03-27 22:19:08 +01:00
Keith Busch 6ebf3b6c6f dm-integrity: fix mismatched queue limits
A user can integritysetup a device with a backing device using a 4k
logical block size, but request the dm device use 1k or 2k. This
mismatch creates an inconsistency such that the dm device would report
limits for IO that it can't actually execute. Fix this by using the
backing device's limits if they are larger.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
2026-03-27 22:18:56 +01:00
Keith Busch 203247c5cb blk-integrity: support arbitrary buffer alignment
A bio segment may have partial interval block data with the rest
continuing into the next segments because direct-io data payloads only
need to align in memory to the device's DMA limits.

At the same time, the protection information may also be split in
multiple segments. The most likely way that may happen is if two
requests merge, or if we're directly using the io_uring user metadata.
The generate/verify, however, only ever accessed the first bip_vec.

Further, it may be possible to unalign the protection fields from the
user space buffer, or if there are odd additional opaque bytes in front
or in back of the protection information metadata region.

Change up the iteration to allow spanning multiple segments. This patch
is mostly a re-write of the protection information handling to allow any
arbitrary alignments, so it's probably easier to review the end result
rather than the diff.

Many controllers are not able to handle interval data composed of
multiple segments when PI is used, so this patch introduces a new
integrity limit that a low level driver can set to notify that it is
capable, default to false. The nvme driver is the first one to enable it
in this patch. Everyone else will force DMA alignment to the logical
block size as before to ensure interval data is always aligned within a
single segment.

Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Link: https://patch.msgid.link/20260313144701.1221652-2-kbusch@meta.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-03-14 07:44:30 -06:00
Keith Busch 8238cb69c0 PCI: Make reset_subordinate hotplug safe
Use the slot reset method when resetting the bridge if the bus contains
hot plug slots. This fixes spurious hot plug events that are triggered
by the secondary bus reset that bypasses the slot's detection disabling.

Resetting a bridge's subordinate bus can be done like this:

  # echo 1 > /sys/bus/pci/devices/0000:50:01.0/reset_subordinate

Prior to this patch, an example kernel message may show something like:

  pcieport 0000:50:01.0: pciehp: Slot(40): Link Down

With this change, the pciehp driver ignores the link event during the
reset, so may show this message instead:

  pcieport 0000:50:01.0: pciehp: Slot(40): Link Down/Up ignored

Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Link: https://patch.msgid.link/20260217160836.2709885-4-kbusch@meta.com
2026-03-09 15:40:28 -05:00
Keith Busch 102c8b26b5 PCI: Allow all bus devices to use the same slot
A PCIe hotplug slot applies to the entire secondary bus. Thus, pciehp only
allocates a single hotplug_slot for the bridge to that bus. The existing
PCI slot, though, would only match to functions on device 0, meaning any
devices beyond that, e.g., ARI functions, are not matched to any slot even
though they share it. A slot reset will break all the missing devices
because the handling skips them.

For example, ARI devices with more than 8 functions fail because their
state is not properly handled, nor is the attached driver notified of the
reset. In the best case, the device will appear unresponsive to the driver,
resulting in unexpected errors. A worse possibility may panic the kernel if
in-flight transactions trigger hardware reported errors like this real
observation:

  vfio-pci 0000:01:00.0: resetting
  vfio-pci 0000:01:00.0: reset done
  {1}[Hardware Error]:  Error 1, type: fatal
  {1}[Hardware Error]:   section_type: PCIe error
  {1}[Hardware Error]:   port_type: 0, PCIe end point
  {1}[Hardware Error]:   version: 0.2
  {1}[Hardware Error]:   command: 0x0140, status: 0x0010
  {1}[Hardware Error]:   device_id: 0000:01:01.0
  {1}[Hardware Error]:   slot: 0
  {1}[Hardware Error]:   secondary_bus: 0x00
  {1}[Hardware Error]:   vendor_id: 0x1d9b, device_id: 0x0207
  {1}[Hardware Error]:   class_code: 020000
  {1}[Hardware Error]:   bridge: secondary_status: 0x0000, control: 0x0000
  {1}[Hardware Error]:   aer_cor_status: 0x00008000, aer_cor_mask: 0x00002000
  {1}[Hardware Error]:   aer_uncor_status: 0x00010000, aer_uncor_mask: 0x00100000
  {1}[Hardware Error]:   aer_uncor_severity: 0x006f6030
  {1}[Hardware Error]:   TLP Header: 0a412800 00192080 60000004 00000004
  GHES: Fatal hardware error but panic disabled
  Kernel panic - not syncing: GHES: Fatal hardware error

Allow a slot to be created to claim all devices on a bus, not just a
matching device. This is done by introducing a sentinel value, named
PCI_SLOT_ALL_DEVICES, which then has the PCI slot match to any device on
the bus. This fixes slot resets for pciehp.

Since 0xff already has special meaning, the chosen value for this new
feature is 0xfe. This will not clash with any actual slot number since they
are limited to 5 bits.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Link: https://patch.msgid.link/20260217160836.2709885-3-kbusch@meta.com
2026-03-09 15:39:07 -05:00
Keith Busch 84226677e0 PCI: Rename __pci_bus_reset() and __pci_slot_reset()
Make the code a little easier to navigate with more descriptive function
names. The two renamed functions here "try" to do to a reset, so make that
clear in the name to distinguish them from other similarly named functions:

  __pci_reset_bus()    -> pci_try_reset_bus()
  __pci_reset_slot()   -> pci_try_reset_slot()

Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Link: https://patch.msgid.link/20260217160836.2709885-2-kbusch@meta.com
2026-03-09 15:27:45 -05:00
Keith Busch 93d0fcdddc cxl/acpi: Fix CXL_ACPI and CXL_PMEM Kconfig tristate mismatch
Commit e7e222ad73 ("cxl: Move devm_cxl_add_nvdimm_bridge() to
cxl_pmem.ko") moves devm_cxl_add_nvdimm_bridge() into the cxl_pmem file,
which has independent config compile options for built-in or module. The
call from cxl_acpi_probe() is guarded by IS_ENABLED(CONFIG_CXL_PMEM),
which evaluates to true for both =y and =m.

When CONFIG_CXL_PMEM=m, a built-in cxl_acpi attempts to reference a
symbol exported by a module, which fails to link. CXL_PMEM cannot simply
be promoted to =y in this configuration because it depends on LIBNVDIMM,
which may itself be =m.

Add a Kconfig dependency to prevent CXL_ACPI from being built-in when
CXL_PMEM is a module. This contrains CXL_ACPI to =m when CXL_PMEM=m,
while still allowing CXL_ACPI to be freely configured when CXL_PMEM is
either built-in or disabled.

[ dj: Fix up commit reference formatting. ]

Fixes: e7e222ad73 ("cxl: Move devm_cxl_add_nvdimm_bridge() to cxl_pmem.ko")
Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Link: https://patch.msgid.link/20260305204057.1516948-1-kbusch@meta.com
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2026-03-06 08:08:53 -07:00
Keith Busch 0f5197ea9a nvme-multipath: fix leak on try_module_get failure
We need to fall back to the synchronous removal if we can't get a
reference on the module needed for the deferred removal.

Fixes: 62188639ec ("nvme-multipath: introduce delayed removal of the multipath head node")
Reviewed-by: Nilay Shroff <nilay@linux.ibm.com>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>
2026-02-27 07:35:15 -08:00
Keith Busch baa47c4f89 nvme-pci: do not try to add queue maps at runtime
The block layer allocates the set's maps once. We can't add special
purpose queues at runtime if they weren't allocated at initialization
time.

Tested-by: Kanchan Joshi <joshi.k@samsung.com>
Reviewed-by: Kanchan Joshi <joshi.k@samsung.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>
2026-02-13 06:47:59 -08:00
Keith Busch 4735b510a0 nvme-pci: cap queue creation to used queues
If the user reduces the special queue count at runtime and resets the
controller, we need to reduce the number of queues and interrupts
requested accordingly rather than start with the pre-allocated queue
count.

Tested-by: Kanchan Joshi <joshi.k@samsung.com>
Reviewed-by: Kanchan Joshi <joshi.k@samsung.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>
2026-02-13 06:47:41 -08:00
Keith Busch 166e31d7db nvme-pci: ensure we're polling a polled queue
A user can change the polled queue count at run time. There's a brief
window during a reset where a hipri task may try to poll that queue
before the block layer has updated the queue maps, which would race with
the now interrupt driven queue and may cause double completions.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kanchan Joshi <joshi.k@samsung.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
2026-02-13 06:47:24 -08:00
Keith Busch 1f5e57c622 PCI: Fix pci_slot_lock () device locking
Like pci_bus_lock(), pci_slot_lock() needs to lock the bridge device to
prevent warnings like:

  pcieport 0000:e2:05.0: unlocked secondary bus reset via: pciehp_reset_slot+0x55/0xa0

Take and release the lock for the bridge providing the slot for the
lock/trylock and unlock routines.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Link: https://patch.msgid.link/20260130165953.751063-3-kbusch@meta.com
2026-02-06 16:53:27 -06:00
Keith Busch 071be3b0b6 nvme-pci: handle changing device dma map requirements
The initial state of dma_needs_unmap may be false, but change to true
while mapping the data iterator. Enabling swiotlb is one such case that
can change the result. The nvme driver needs to save the mapped dma
vectors to be unmapped later, so allocate as needed during iteration
rather than assume it was always allocated at the beginning. This fixes
a NULL dereference from accessing an uninitialized dma_vecs when the
device dma unmapping requirements change mid-iteration.

Fixes: b8b7570a7e ("nvme-pci: fix dma unmapping when using PRPs and not using the IOVA mapping")
Link: https://lore.kernel.org/linux-nvme/20260202125738.1194899-1-pradeep.pragallapati@oss.qualcomm.com/
Reported-by: Pradeep P V K <pradeep.pragallapati@oss.qualcomm.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>
2026-02-05 07:29:10 -08:00
Keith Busch 72a41750f1 block: remove bio_last_bvec_all
There are no more callers of this function after commit f6b2d8b134
("btrfs: track the next file offset in struct btrfs_bio_ctrl"), so
remove the function.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Kanchan Joshi <joshi.k@samsung.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-01-26 21:07:48 -07:00
Keith Busch a0750fae73 blk-mq-dma: always initialize dma state
Ensure the dma state is initialized when we're not using the contiguous
iova, otherwise the caller may be using a stale state from a previous
request that could use the coalesed iova allocation.

Fixes: 2f6b2565d4 ("block: accumulate memory segment gaps per bio")
Reported-by: Sebastian Ott <sebott@redhat.com>
Tested-by: Sebastian Ott <sebott@redhat.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-12-10 13:41:11 -07:00
Keith Busch 2516c246d0 block: consider discard merge last
If the next discard range is contiguous with the current range being
considered, it's cheaper to expand the current range than to append an
additional bio.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-11-17 09:39:36 -07:00
Keith Busch 3749ea4dee null_blk: fix zone read length beyond write pointer
Fix up the divisor calculating the number of zone sectors being read and
handle a read that straddles the zone write pointer. The length is
rounded up a sector boundary, so be sure to truncate any excess bytes
off to avoid copying past the data segment.

Fixes: 3451cf34f5 ("null_blk: allow byte aligned memory offsets")
Signed-off-by: Keith Busch <kbusch@kernel.org>
Tested-by: Bart van Assche <bvanassche@acm.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-11-12 10:02:56 -07:00
Keith Busch fd9ecd0052 block: fix merging data-less bios
The data segment gaps the block layer tracks doesn't apply to bio's that
don't have data. Skip calculating this to fix a NULL pointer access.

Fixes: 2f6b2565d4 ("block: accumulate memory segment gaps per bio")
Reported-by: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Yu Kuai <yukuai@fnnas.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-11-11 08:35:59 -07:00
Keith Busch bc840b21a2 nvme: remove virtual boundary for sgl capable devices
The nvme virtual boundary is only required for the PRP format. Devices
that can use SGL for DMA don't need it for IO queues. Drop reporting it
for such devices; rdma fabrics controllers will continue to use the
limit as they currently don't report any boundary requirements, but tcp
and fc never needed it in the first place so they get to report no
virtual boundary.

Applications may continue to align to the same virtual boundaries for
optimization purposes if they want, and the driver will continue to
decide whether to use the PRP format the same as before if the IO allows
it.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-11-06 18:11:58 -07:00
Keith Busch 2f6b2565d4 block: accumulate memory segment gaps per bio
The blk-mq dma iterator has an optimization for requests that align to
the device's iommu merge boundary. This boundary may be larger than the
device's virtual boundary, but the code had been depending on that queue
limit to know ahead of time if the request is guaranteed to align to
that optimization.

Rather than rely on that queue limit, which many devices may not report,
save the lowest set bit of any boundary gap between each segment in the
bio while checking the segments. The request stores the value for
merging and quickly checking per io if the request can use iova
optimizations.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-11-06 18:11:58 -07:00
Keith Busch 3451cf34f5 null_blk: allow byte aligned memory offsets
Allowing byte aligned memory provides a nice testing ground for
direct-io.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Tested-by: Hans Holmberg <hans.holmberg@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-11-06 16:28:55 -07:00
Keith Busch 262a3dd04e null_blk: single kmap per bio segment
Rather than kmap the the request bio segment for each sector, do
the mapping just once.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Tested-by: Hans Holmberg <hans.holmberg@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-11-06 16:27:36 -07:00
Keith Busch 8459283819 null_blk: consistently use blk_status_t
No need to mix errno and blk_status_t error types. Just use the standard
block layer type.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Tested-by: Hans Holmberg <hans.holmberg@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-11-06 16:27:21 -07:00
Keith Busch 1165d20f4d null_blk: simplify copy_from_nullb
It always returns success, so the code that saves the errors status, but
proceeds without checking it looks a bit odd. Clean this up.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Tested-by: Hans Holmberg <hans.holmberg@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-11-06 16:27:21 -07:00
Keith Busch 03b3bcd319 nvme: fix admin request_queue lifetime
The namespaces can access the controller's admin request_queue, and
stale references on the namespaces may exist after tearing down the
controller. Ensure the admin request_queue is active by moving the
controller's 'put' to after all controller references have been released
to ensure no one is can access the request_queue. This fixes a reported
use-after-free bug:

  BUG: KASAN: slab-use-after-free in blk_queue_enter+0x41c/0x4a0
  Read of size 8 at addr ffff88c0a53819f8 by task nvme/3287
  CPU: 67 UID: 0 PID: 3287 Comm: nvme Tainted: G            E       6.13.2-ga1582f1a031e #15
  Tainted: [E]=UNSIGNED_MODULE
  Hardware name: Jabil /EGS 2S MB1, BIOS 1.00 06/18/2025
  Call Trace:
   <TASK>
   dump_stack_lvl+0x4f/0x60
   print_report+0xc4/0x620
   ? _raw_spin_lock_irqsave+0x70/0xb0
   ? _raw_read_unlock_irqrestore+0x30/0x30
   ? blk_queue_enter+0x41c/0x4a0
   kasan_report+0xab/0xe0
   ? blk_queue_enter+0x41c/0x4a0
   blk_queue_enter+0x41c/0x4a0
   ? __irq_work_queue_local+0x75/0x1d0
   ? blk_queue_start_drain+0x70/0x70
   ? irq_work_queue+0x18/0x20
   ? vprintk_emit.part.0+0x1cc/0x350
   ? wake_up_klogd_work_func+0x60/0x60
   blk_mq_alloc_request+0x2b7/0x6b0
   ? __blk_mq_alloc_requests+0x1060/0x1060
   ? __switch_to+0x5b7/0x1060
   nvme_submit_user_cmd+0xa9/0x330
   nvme_user_cmd.isra.0+0x240/0x3f0
   ? force_sigsegv+0xe0/0xe0
   ? nvme_user_cmd64+0x400/0x400
   ? vfs_fileattr_set+0x9b0/0x9b0
   ? cgroup_update_frozen_flag+0x24/0x1c0
   ? cgroup_leave_frozen+0x204/0x330
   ? nvme_ioctl+0x7c/0x2c0
   blkdev_ioctl+0x1a8/0x4d0
   ? blkdev_common_ioctl+0x1930/0x1930
   ? fdget+0x54/0x380
   __x64_sys_ioctl+0x129/0x190
   do_syscall_64+0x5b/0x160
   entry_SYSCALL_64_after_hwframe+0x4b/0x53
  RIP: 0033:0x7f765f703b0b
  Code: ff ff ff 85 c0 79 9b 49 c7 c4 ff ff ff ff 5b 5d 4c 89 e0 41 5c c3 66 0f 1f 84 00 00 00 00 00 f3 0f 1e fa b8 10 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d dd 52 0f 00 f7 d8 64 89 01 48
  RSP: 002b:00007ffe2cefe808 EFLAGS: 00000202 ORIG_RAX: 0000000000000010
  RAX: ffffffffffffffda RBX: 00007ffe2cefe860 RCX: 00007f765f703b0b
  RDX: 00007ffe2cefe860 RSI: 00000000c0484e41 RDI: 0000000000000003
  RBP: 0000000000000000 R08: 0000000000000003 R09: 0000000000000000
  R10: 00007f765f611d50 R11: 0000000000000202 R12: 0000000000000003
  R13: 00000000c0484e41 R14: 0000000000000001 R15: 00007ffe2cefea60
   </TASK>

Reported-by: Casey Chen <cachen@purestorage.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
2025-11-05 12:50:46 -08:00
Keith Busch 0194b65ab5 nvme-pci: use blk_map_iter for p2p metadata
The dma_map_bvec helper doesn't work for p2p data, so use the same
blk_map_iter method that sgl uses for this memory type.

Reported-by: Leon Romanovsky <leon@kernel.org>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>
2025-10-22 19:46:25 -07:00
Keith Busch 0ecf0e6748 io_uring/fdinfo: show SQEs for no array setup
The sq_head indicates the index directly in the submission queue when
the IORING_SETUP_NO_SQARRAY option is used, so use that instead of
skipping showing the entries.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-10-22 16:09:41 -06:00
Keith Busch 5c5028ee59 block: rename min_segment_size
Despite its name, the block layer is fine with segments smaller that the
"min_segment_size" limit. The value is an optimization limit indicating
the largest segment that can be used without considering boundary
limits. Smaller segments can take a fast path, so give it a name that
reflects that: max_fast_segment_size.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-10-22 07:39:39 -06:00
Keith Busch 1cba30bf9f io_uring: add support for IORING_SETUP_SQE_MIXED
Normal rings support 64b SQEs for posting submissions, while certain
features require the ring to be configured with IORING_SETUP_SQE128, as
they need to convey more information per submission. This, in turn,
makes ALL the SQEs be 128b in size. This is somewhat wasteful and
inefficient, particularly when only certain SQEs need to be of the
bigger variant.

This adds support for setting up a ring with mixed SQE sizes, using
IORING_SETUP_SQE_MIXED. When setup in this mode, SQEs posted to the ring
may be either 64b or 128b in size. If a SQE is 128b in size, then opcode
will be set to a variante to indicate that this is the case. Any other
non-128b opcode will assume the SQ's default size.

SQEs on these types of mixed rings may also utilize NOP with skip
success set.  This can happen if the ring is one (small) SQE entry away
from wrapping, and an attempt is made to get a 128b SQE. As SQEs must be
contiguous in the SQ ring, a 128b SQE cannot wrap the ring. For this
case, a single NOP SQE should be inserted with the SKIP_SUCCESS flag
set. The kernel will process this as a normal NOP and without posting a
CQE.

Signed-off-by: Keith Busch <kbusch@kernel.org>
[axboe: {} style fix and assign sqe before opcode read]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-10-22 07:34:57 -06:00
Keith Busch 79525b51ac io_uring: fix nvme's 32b cqes on mixed cq
The nvme uring_cmd only uses 32b CQEs. If the ring uses a mixed CQ, then
we need to make sure we flag the completion as a 32b CQE.

On the other hand, if nvme uring_cmd was using a dedicated 32b CQE, the
posting was missing the extra memcpy because it only applied to bit CQEs
on a mixed CQ.

Fixes: e26dca67fd ("io_uring: add support for IORING_SETUP_CQE_MIXED")
Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-09-20 06:26:38 -06:00
Keith Busch d0d1d52231 blk-map: provide the bdev to bio if one exists
We can now safely provide a block device when extracting user pages for
driver and user passthrough commands. Set the bdev so the caller doesn't
have to do that later. This has an additional  benefit of being able to
extract P2P pages in the passthrough path.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-09-09 10:35:28 -06:00
Keith Busch d57447ffb5 blk-mq-dma: bring back p2p request flags
We only need to consider data and metadata dma mapping types separately.
The request and bio integrity payload have enough flag bits to
internally track the mapping type for each. Use these so the caller
doesn't need to track them, and provide separete request and integrity
helpers to the common code. This will make it easier to scale new
mappings, like the proposed MMIO attribute, without burdening the caller
to track such things.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-09-09 10:33:35 -06:00
Keith Busch 05ceea5d3e blk-integrity: enable p2p source and destination
Set the extraction flags to allow p2p pages for the metadata buffer if
the block device allows it. Similar to data payloads, ensure the bio
does not use merging if we see a p2p page.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-09-09 10:33:27 -06:00
Keith Busch b475272f03 iov_iter: remove iov_iter_is_aligned
No more callers.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-09-09 10:27:01 -06:00
Keith Busch 69d7ed5b9e blk-integrity: use simpler alignment check
We're checking length and addresses against the same alignment value, so
use the more simple iterator check.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-09-09 10:27:01 -06:00
Keith Busch 9eab1d4e0d block: remove bdev_iter_is_aligned
No more callers.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-09-09 10:27:01 -06:00
Keith Busch 7eac331869 iomap: simplify direct io validity check
The block layer checks all the segments for validity later, so no need
for an early check. Just reduce it to a simple position and total length
check, and defer the more invasive segment checks to the block layer.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-09-09 10:27:01 -06:00
Keith Busch 5ff3f74e14 block: simplify direct io validity check
The block layer checks all the segments for validity later, so no need
for an early check. Just reduce it to a simple position and total length
check, and defer the more invasive segment checks to the block layer.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-09-09 10:27:01 -06:00
Keith Busch 20a0e6276e block: align the bio after building it
Instead of ensuring each vector is block size aligned while constructing
the bio, just ensure the entire size is aligned after it's built. This
makes getting bio pages more flexible to accepting device valid io
vectors that would otherwise get rejected by alignment checks.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-09-09 10:27:01 -06:00
Keith Busch 743bf2e0c4 block: add size alignment to bio_iov_iter_get_pages
The block layer tries to align bio vectors to the block device's logical
block size. Some cases don't have a block device, or we may need to
align to something larger, which we can't derive it from the queue
limits. Have the caller specify what they want, or allow any length
alignment if nothing was specified. Since the most common use case
relies on the block device's limits, a helper function is provided.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-09-09 10:27:01 -06:00
Keith Busch fec2e70572 block: check for valid bio while splitting
We're already iterating every segment, so check these for a valid IO
lengths at the same time. Individual segment lengths will not be checked
on passthrough commands. The read/write command segments must be sized
to the dma alignment.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-09-09 10:27:01 -06:00
Keith Busch 94ce55046c nvme-pci: convert metadata mapping to dma iter
Aligns data and metadata to the similar dma mapping scheme and removes
one more user of the scatter-gather dma mapping.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20250813153153.3260897-10-kbusch@meta.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-08-25 07:44:39 -06:00
Keith Busch f0887e2a52 nvme-pci: create common sgl unmapping helper
This can be reused by metadata sgls once that starts using the blk-mq
dma api.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20250813153153.3260897-9-kbusch@meta.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-08-25 07:44:39 -06:00
Keith Busch c16b52a0a0 blk-integrity: use iterator for mapping sg
Modify blk_rq_map_integrity_sg to use the blk-mq mapping iterator. This
produces more efficient code and converges the integrity mapping
implementations to reduce future maintenance burdens.

The function implementation moves from blk-integrity.c to blk-mq-dma.c
in order to use the types and functions private to that file.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20250813153153.3260897-8-kbusch@meta.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-08-25 07:44:39 -06:00
Keith Busch fec9b16dc5 blk-mq-dma: add scatter-less integrity data DMA mapping
Similar to regular data, introduce more efficient integrity mapping
helpers that does away with the scatterlist structure. This uses the
block mapping iterator to add IOVA segments if IOMMU is enabled, or maps
directly if not. This also supports P2P segements if integrity data ever
wants to allocate that type of memory.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Kanchan Joshi <joshi.k@samsung.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20250813153153.3260897-7-kbusch@meta.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-08-25 07:44:39 -06:00
Keith Busch e2be2ba6d2 blk-mq-dma: move common dma start code to a helper
In preparing for dma mapping integrity metadata, move the common dma
setup to a helper.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Kanchan Joshi <joshi.k@samsung.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20250813153153.3260897-6-kbusch@meta.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-08-25 07:44:39 -06:00
Keith Busch 7092639031 blk-mq: remove REQ_P2PDMA flag
It's not serving any particular purpose. pci_p2pdma_state() already has
all the appropriate checks, so the config and flag checks are not
guarding anything.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Kanchan Joshi <joshi.k@samsung.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20250813153153.3260897-5-kbusch@meta.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-08-25 07:44:39 -06:00
Keith Busch 92fb75fd14 blk-mq-dma: require unmap caller provide p2p map type
In preparing for integrity dma mappings, we can't rely on the request
flag because data and metadata may have different mapping types.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Kanchan Joshi <joshi.k@samsung.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20250813153153.3260897-4-kbusch@meta.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-08-25 07:44:39 -06:00
Keith Busch dae75dead2 blk-mq-dma: provide the bio_vec array being iterated
This will make it easier to add different sources of the bvec array,
like for upcoming integrity support, rather than assume to use the bio's
bi_io_vec. It also makes iterating "special" payloads more in common
with iterating normal payloads.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kanchan Joshi <joshi.k@samsung.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20250813153153.3260897-3-kbusch@meta.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-08-25 07:44:38 -06:00
Keith Busch 7a6fc1634c blk-mq-dma: create blk_map_iter type
The req_iterator happens to have a similar fields to what the dma
iterator needs, but we're not necessarily iterating a request's
bi_io_vec. Create a new type that can be amended for additional future
use.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kanchan Joshi <joshi.k@samsung.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20250813153153.3260897-2-kbusch@meta.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-08-25 07:44:38 -06:00
Keith Busch b1779e4f20 vfio/type1: conditional rescheduling while pinning
A large DMA mapping request can loop through dma address pinning for
many pages. In cases where THP can not be used, the repeated vmf_insert_pfn can
be costly, so let the task reschedule as need to prevent CPU stalls. Failure to
do so has potential harmful side effects, like increased memory pressure
as unrelated rcu tasks are unable to make their reclaim callbacks and
result in OOM conditions.

 rcu: INFO: rcu_sched self-detected stall on CPU
 rcu:   36-....: (20999 ticks this GP) idle=b01c/1/0x4000000000000000 softirq=35839/35839 fqs=3538
 rcu:            hardirqs   softirqs   csw/system
 rcu:    number:        0        107            0
 rcu:   cputime:       50          0        10446   ==> 10556(ms)
 rcu:   (t=21075 jiffies g=377761 q=204059 ncpus=384)
...
  <TASK>
  ? asm_sysvec_apic_timer_interrupt+0x16/0x20
  ? walk_system_ram_range+0x63/0x120
  ? walk_system_ram_range+0x46/0x120
  ? pgprot_writethrough+0x20/0x20
  lookup_memtype+0x67/0xf0
  track_pfn_insert+0x20/0x40
  vmf_insert_pfn_prot+0x88/0x140
  vfio_pci_mmap_huge_fault+0xf9/0x1b0 [vfio_pci_core]
  __do_fault+0x28/0x1b0
  handle_mm_fault+0xef1/0x2560
  fixup_user_fault+0xf5/0x270
  vaddr_get_pfns+0x169/0x2f0 [vfio_iommu_type1]
  vfio_pin_pages_remote+0x162/0x8e0 [vfio_iommu_type1]
  vfio_iommu_type1_ioctl+0x1121/0x1810 [vfio_iommu_type1]
  ? futex_wake+0x1c1/0x260
  x64_sys_call+0x234/0x17a0
  do_syscall_64+0x63/0x130
  ? exc_page_fault+0x63/0x130
  entry_SYSCALL_64_after_hwframe+0x4b/0x53

Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Paul E. McKenney <paulmck@kernel.org>
Link: https://lore.kernel.org/r/20250715184622.3561598-1-kbusch@meta.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2025-08-05 15:41:19 -06:00
Keith Busch 4e6e151cf9 nvme-pci: fix leak on sgl setup error
We need to free the descriptor that was allocated. We also don't
necessarily need to unmap each sgl entry, which was previously being
attempted unconditionally.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2025-07-31 06:35:51 -07:00
Keith Busch 5b2c214a95 nvme-pci: try function level reset on init failure
NVMe devices from multiple vendors appear to get stuck in a reset state
that we can't get out of with an NVMe level Controller Reset. The kernel
would report these with messages that look like:

  Device not ready; aborting reset, CSTS=0x1

These have historically required a power cycle to make them usable
again, but in many cases, a PCIe FLR is sufficient to restart operation
without a power cycle. Try it if the initial controller reset fails
during any nvme reset attempt.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Nitesh Shetty <nj.shetty@samsung.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2025-07-17 17:46:33 +02:00
Keith Busch dd2c185489 nvme: reset delayed remove_work after reconnect
The remove_work will proceed with permanently disconnecting on the
initial final path failure if the head shows no paths after the delay.
If a new path connects while the remove_work is pending, and if that new
path happens to disconnect before that remove_work executes, the delayed
removal should reset based on the most recent path disconnect time, but
queue_delayed_work() won't do anything if the work is already pending.
Attempt to cancel the delayed work when a new path connects, and use
mod_delayed_work() in case the remove_work remains pending anyway.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Nilay Shroff <nilay@linux.ibm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2025-06-26 13:04:35 +02:00
Keith Busch c538f400fa io_uring: consistently use rcu semantics with sqpoll thread
The sqpoll thread is dereferenced with rcu read protection in one place,
so it needs to be annotated as an __rcu type, and should consistently
use rcu helpers for access and assignment to make sparse happy.

Since most of the accesses occur under the sqd->lock, we can use
rcu_dereference_protected() without declaring an rcu read section.
Provide a simple helper to get the thread from a locked context.

Fixes: ac0b8b327a ("io_uring: fix use-after-free of sq->thread in __io_uring_show_fdinfo()")
Signed-off-by: Keith Busch <kbusch@kernel.org>
Link: https://lore.kernel.org/r/20250611205343.1821117-1-kbusch@meta.com
[axboe: fold in fix for register.c]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-06-12 08:17:09 -06:00
Keith Busch 10f4a7cd72 nvme: fix command limits status code
The command specific status code, 0x183, was introduced in the NVMe 2.0
specification defined to "Command Size Limits Exceeded" and only ever
applied to DSM and Copy commands.  Fix the name and, remove the
incorrect translation to error codes and special treatment in the
target code for it.

Fixes: 3b7c33b28a ("nvme.h: add Write Zeroes definitions")
Cc: Chaitanya Kulkarni <chaitanyak@nvidia.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2025-06-04 09:51:10 +02:00
Keith Busch 1c9a93bf1d dmapool: add NUMA affinity support
Introduce dma_pool_create_node(), like dma_pool_create() but taking an
additional NUMA node argument. Allocate struct dma_pool on the desired
node, and store the node on dma_pool for allocating struct dma_page.
Make dma_pool_create() an alias for dma_pool_create_node() with node set
to NUMA_NO_NODE.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Caleb Sander Mateos <csander@purestorage.com>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Kanchan Joshi <joshi.k@samsung.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2025-05-20 05:34:27 +02:00
Keith Busch 3d8932133d nvme-pci: acquire cq_poll_lock in nvme_poll_irqdisable
We need to lock this queue for that condition because the timeout work
executes per-namespace and can poll the poll CQ.

Reported-by: Hannes Reinecke <hare@kernel.org>
Closes: https://lore.kernel.org/all/20240902130728.1999-1-hare@kernel.org/
Fixes: a0fa9647a5 ("NVMe: add blk polling support")
Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Daniel Wagner <wagi@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2025-05-13 07:57:11 +02:00
Keith Busch 8098514bd5 block: always allocate integrity buffer when required
Many nvme metadata formats can not strip or generate the metadata on the
controller side. For these formats, a host provided integrity buffer is
mandatory even if it isn't checked.

The block integrity read_verify and write_generate attributes prevent
allocating the metadata buffer, but we need it when the format requires
it, otherwise reads and writes will be rejected by the driver with IO
errors.

Assume the integrity buffer can be offloaded to the controller if the
metadata size is the same as the protection information size. Otherwise
provide an unchecked host buffer when the read verify or write
generation attributes are disabled. This fixes the following nvme
warning:

 ------------[ cut here ]------------
 WARNING: CPU: 1 PID: 371 at drivers/nvme/host/core.c:1036 nvme_setup_rw+0x122/0x210
 ...
 RIP: 0010:nvme_setup_rw+0x122/0x210
 ...
 Call Trace:
  <TASK>
  nvme_setup_cmd+0x1b4/0x280
  nvme_queue_rqs+0xc4/0x1f0 [nvme]
  blk_mq_dispatch_queue_requests+0x24a/0x430
  blk_mq_flush_plug_list+0x50/0x140
  __blk_flush_plug+0xc1/0x100
  __submit_bio+0x1c1/0x360
  ? submit_bio_noacct_nocheck+0x2d6/0x3c0
  submit_bio_noacct_nocheck+0x2d6/0x3c0
  ? submit_bio_noacct+0x47/0x4c0
  submit_bio_wait+0x48/0xa0
  __blkdev_direct_IO_simple+0xee/0x210
  ? current_time+0x1d/0x100
  ? current_time+0x1d/0x100
  ? __bio_clone+0xb0/0xb0
  blkdev_read_iter+0xbb/0x140
  vfs_read+0x239/0x310
  ksys_read+0x58/0xc0
  do_syscall_64+0x6c/0x180
  entry_SYSCALL_64_after_hwframe+0x4b/0x53

Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20250509153802.3482493-1-kbusch@meta.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-05-12 07:14:03 -06:00
Keith Busch 38e8397dde nvme: use fdp streams if write stream is provided
Maps a user requested write stream to an FDP placement ID if possible.

Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Nitesh Shetty <nj.shetty@samsung.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Kanchan Joshi <joshi.k@samsung.com>
Link: https://lore.kernel.org/r/20250506121732.8211-12-joshi.k@samsung.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-05-06 07:46:44 -06:00
Keith Busch 30b5f20bb2 nvme: register fdp parameters with the block layer
Register the device data placement limits if supported. This is just
registering the limits with the block layer. Nothing beyond reporting
these attributes is happening in this patch.

Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Nitesh Shetty <nj.shetty@samsung.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Kanchan Joshi <joshi.k@samsung.com>
Link: https://lore.kernel.org/r/20250506121732.8211-11-joshi.k@samsung.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-05-06 07:46:43 -06:00
Keith Busch 02040353f4 io_uring: enable per-io write streams
Allow userspace to pass a per-I/O write stream in the SQE:

      __u8 write_stream;

The __u8 type matches the size the filesystems and block layer support.

Application can query the supported values from the block devices
max_write_streams sysfs attribute. Unsupported values are ignored by
file operations that do not support write streams or rejected with an
error by those that support them.

Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Nitesh Shetty <nj.shetty@samsung.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Kanchan Joshi <joshi.k@samsung.com>
Link: https://lore.kernel.org/r/20250506121732.8211-7-joshi.k@samsung.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-05-06 07:46:43 -06:00
Keith Busch d2f526ba27 block: introduce max_write_streams queue limit
Drivers with hardware that support write streams need a way to export how
many are available so applications can generically query this.

Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Nitesh Shetty <nj.shetty@samsung.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
[hch: renamed hints to streams, removed stacking]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Kanchan Joshi <joshi.k@samsung.com>
Link: https://lore.kernel.org/r/20250506121732.8211-4-joshi.k@samsung.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-05-06 07:46:43 -06:00
Keith Busch a75401227e nvme-pci: fix queue unquiesce check on slot_reset
A zero return means the reset was successfully scheduled. We don't want
to unquiesce the queues while the reset_work is pending, as that will
just flush out requeued requests to a failed completion.

Fixes: 71a5bb153b ("nvme: ensure disabling pairs with unquiesce")
Reported-by: Dhankaran Singh Ajravat <dhankaran@meta.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2025-04-29 08:00:34 -05:00
Keith Busch 334f795ff8 Revert "io_uring/rsrc: simplify the bvec iter count calculation"
This reverts commit 2a51c327d4.

The kernel registered bvecs do use the iov_iter_advance() API, so we
can't rely on this simplification anymore.

Fixes: 27cb27b6d5 ("io_uring: add support for kernel registered bvecs")
Reported-by: Caleb Sander Mateos <csander@purestorage.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Caleb Sander Mateos <csander@purestorage.com>
Link: https://lore.kernel.org/r/20250310184825.569371-1-kbusch@meta.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-03-10 16:24:43 -06:00
Keith Busch 3f674e7b67 nvme-pci: fix stuck reset on concurrent DPC and HP
The PCIe error handling has the nvme driver quiesce the device, attempt
to restart it, then wait for that restart to complete.

A PCIe DPC event also toggles the PCIe link. If the slot doesn't have
out-of-band presence detection, this will trigger a pciehp
re-enumeration.

The error handling that calls nvme_error_resume is holding the device
lock while this happens. This lock blocks pciehp's request to disconnect
the driver from proceeding.

Meanwhile the nvme's reset can't make forward progress because its
device isn't there anymore with outstanding IO, and the timeout handler
won't do anything to fix it because the device is undergoing error
handling.

End result: deadlocked.

Fix this by having the timeout handler short cut the disabling for a
disconnected PCIe device. The downside is that we're relying on an IO
timeout to clean up this mess, which could be a minute by default.

Tested-by: Nilay Shroff <nilay@linux.ibm.com>
Reviewed-by: Nilay Shroff <nilay@linux.ibm.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
2025-03-10 09:15:48 -07:00
Keith Busch 916b7f42b3 kvm: retry nx_huge_page_recovery_thread creation
A VMM may send a non-fatal signal to its threads, including vCPU tasks,
at any time, and thus may signal vCPU tasks during KVM_RUN.  If a vCPU
task receives the signal while its trying to spawn the huge page recovery
vhost task, then KVM_RUN will fail due to copy_process() returning
-ERESTARTNOINTR.

Rework call_once() to mark the call complete if and only if the called
function succeeds, and plumb the function's true error code back to the
call_once() invoker.  This provides userspace with the correct, non-fatal
error code so that the VMM doesn't terminate the VM on -ENOMEM, and allows
subsequent KVM_RUN a succeed by virtue of retrying creation of the NX huge
page task.

Co-developed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
[implemented the kvm user side]
Signed-off-by: Keith Busch <kbusch@kernel.org>
Message-ID: <20250227230631.303431-3-kbusch@meta.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-03-01 02:54:18 -05:00
Keith Busch cb380909ae vhost: return task creation error instead of NULL
Lets callers distinguish why the vhost task creation failed. No one
currently cares why it failed, so no real runtime change from this
patch, but that will not be the case for long.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Message-ID: <20250227230631.303431-2-kbusch@meta.com>
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-03-01 02:52:52 -05:00
Keith Busch ed9f3112a8 io_uring: cache nodes and mapped buffers
Frequent alloc/free cycles on these is pretty costly. Use an io cache to
more efficiently reuse these buffers.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Link: https://lore.kernel.org/r/20250227223916.143006-7-kbusch@meta.com
[axboe: fix imu leak]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-02-28 07:05:46 -07:00
Keith Busch 1f6540e2aa ublk: zc register/unregister bvec
Provide new operations for the user to request mapping an active request
to an io uring instance's buf_table. The user has to provide the index
it wants to install the buffer.

A reference count is taken on the request to ensure it can't be
completed while it is active in a ring's buf_table.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Link: https://lore.kernel.org/r/20250227223916.143006-6-kbusch@meta.com
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-02-28 07:05:41 -07:00
Keith Busch 27cb27b6d5 io_uring: add support for kernel registered bvecs
Provide an interface for the kernel to leverage the existing
pre-registered buffers that io_uring provides. User space can reference
these later to achieve zero-copy IO.

User space must register an empty fixed buffer table with io_uring in
order for the kernel to make use of it.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Link: https://lore.kernel.org/r/20250227223916.143006-5-kbusch@meta.com
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-02-28 07:05:36 -07:00
Keith Busch ff92d824d0 io_uring/rw: move fixed buffer import to issue path
Registered buffers may depend on a linked command, which makes the prep
path too early to import. Move to the issue path when the node is
actually needed like all the other users of fixed buffers.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Link: https://lore.kernel.org/r/20250227223916.143006-3-kbusch@meta.com
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-02-28 07:05:26 -07:00
Keith Busch 2a61e63891 io_uring/rw: move buffer_select outside generic prep
Cleans up the generic rw prep to not require the do_import flag. Use a
different prep function for callers that might need buffer select.

Based-on-a-patch-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Link: https://lore.kernel.org/r/20250227223916.143006-2-kbusch@meta.com
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-02-28 07:05:21 -07:00
Keith Busch a14ca7a413 io_uring/nop: reuse req->buf_index
There is already a field in io_kiocb that can store a registered buffer
index, use that instead of stashing the value into struct io_nop.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Pavel Begunkov <asml.silence@gmail.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250224213116.3509093-3-kbusch@meta.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-02-27 07:17:39 -07:00
Keith Busch c5b47d5a8c io_uring/rsrc: remove redundant check for valid imu
The only caller to io_buffer_unmap already checks if the node's buf is
not null, so no need to check again.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Pavel Begunkov <asml.silence@gmail.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250224213116.3509093-2-kbusch@meta.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-02-27 07:17:39 -07:00
Keith Busch 00817f0f1c nvme-ioctl: fix leaked requests on mapping error
All the callers assume nvme_map_user_request() frees the request on a
failure. This wasn't happening on invalid metadata or io_uring command
flags, so we've been leaking those requests.

Fixes: 23fd22e55b ("nvme: wire up fixed buffer support for nvme passthrough")
Fixes: 7c2fd76048 ("nvme: fix metadata handling in nvme-passthrough")
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Kanchan Joshi <joshi.k@samsung.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>
2025-02-25 09:09:18 -08:00
Keith Busch 2d1a2dab95 nvme: make nvme_tls_attrs_group static
To suppress the compiler "warning: symbol 'nvme_tls_attrs_group' was not
declared. Should it be static?"

Fixes: 1e48b34c9b ("nvme: split off TLS sysfs attributes into a separate group")
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Keith Busch <kbusch@kernel.org>
2025-01-31 10:14:27 -08:00