Pull virtio updates from Michael Tsirkin:
"A small number of improvements all over the place"
* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
virtio_vdpa: remove redundant check on desc
virtio_fs: store actual queue index in mq_map
virtio_fs: add informative log for new tag discovery
virtio: Make vring_new_virtqueue support packed vring
virtio_pmem: Add freeze/restore callbacks
vdpa/mlx5: Fix suboptimal range on iotlb iteration
Enhance the device probing process by adding a log message when a new
virtio-fs tag is successfully discovered. This improvement provides
better visibility into the initialization of virtio-fs devices.
Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Message-Id: <20241006184324.8497-1-mgurtovoy@nvidia.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
All fuse requests use folios instead of pages for transferring data.
Remove pages from the requests and exclusively use folios.
No functional changes.
[SzM: rename back folio_descs -> descs, etc.]
Signed-off-by: Joanne Koong <joannelkoong@gmail.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Until all requests have been converted to use folios instead of pages,
virtio will need to support both types. Once all requests have been
converted, then virtio will support just folios.
No functional changes.
Signed-off-by: Joanne Koong <joannelkoong@gmail.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
When invoking virtio_fs_enqueue_req() through kworker, both the
allocation of the sg array and the bounce buffer still use GFP_ATOMIC.
Considering the size of the sg array may be greater than PAGE_SIZE, use
GFP_NOFS instead of GFP_ATOMIC to lower the possibility of memory
allocation failure and to avoid unnecessarily depleting the atomic
reserves. GFP_NOFS is not passed to virtio_fs_enqueue_req() directly,
GFP_KERNEL and memalloc_nofs_{save|restore} helpers are used instead.
It may seem OK to pass GFP_NOFS to virtio_fs_enqueue_req() as well when
queuing the request for the first time, but this is not the case. The
reason is that fuse_request_queue_background() may call
->queue_request_and_unlock() while holding fc->bg_lock, which is a
spin-lock. Therefore, still use GFP_ATOMIC for it.
Signed-off-by: Hou Tao <houtao1@huawei.com>
Reviewed-by: Jingbo Xu <jefflexu@linux.alibaba.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
When trying to insert a 10MB kernel module kept in a virtio-fs with cache
disabled, the following warning was reported:
------------[ cut here ]------------
WARNING: CPU: 1 PID: 404 at mm/page_alloc.c:4551 ......
Modules linked in:
CPU: 1 PID: 404 Comm: insmod Not tainted 6.9.0-rc5+ #123
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996) ......
RIP: 0010:__alloc_pages+0x2bf/0x380
......
Call Trace:
<TASK>
? __warn+0x8e/0x150
? __alloc_pages+0x2bf/0x380
__kmalloc_large_node+0x86/0x160
__kmalloc+0x33c/0x480
virtio_fs_enqueue_req+0x240/0x6d0
virtio_fs_wake_pending_and_unlock+0x7f/0x190
queue_request_and_unlock+0x55/0x60
fuse_simple_request+0x152/0x2b0
fuse_direct_io+0x5d2/0x8c0
fuse_file_read_iter+0x121/0x160
__kernel_read+0x151/0x2d0
kernel_read+0x45/0x50
kernel_read_file+0x1a9/0x2a0
init_module_from_file+0x6a/0xe0
idempotent_init_module+0x175/0x230
__x64_sys_finit_module+0x5d/0xb0
x64_sys_call+0x1c3/0x9e0
do_syscall_64+0x3d/0xc0
entry_SYSCALL_64_after_hwframe+0x4b/0x53
......
</TASK>
---[ end trace 0000000000000000 ]---
The warning is triggered as follows:
1) syscall finit_module() handles the module insertion and it invokes
kernel_read_file() to read the content of the module first.
2) kernel_read_file() allocates a 10MB buffer by using vmalloc() and
passes it to kernel_read(). kernel_read() constructs a kvec iter by
using iov_iter_kvec() and passes it to fuse_file_read_iter().
3) virtio-fs disables the cache, so fuse_file_read_iter() invokes
fuse_direct_io(). As for now, the maximal read size for kvec iter is
only limited by fc->max_read. For virtio-fs, max_read is UINT_MAX, so
fuse_direct_io() doesn't split the 10MB buffer. It saves the address and
the size of the 10MB-sized buffer in out_args[0] of a fuse request and
passes the fuse request to virtio_fs_wake_pending_and_unlock().
4) virtio_fs_wake_pending_and_unlock() uses virtio_fs_enqueue_req() to
queue the request. Because virtiofs need DMA-able address, so
virtio_fs_enqueue_req() uses kmalloc() to allocate a bounce buffer for
all fuse args, copies these args into the bounce buffer and passed the
physical address of the bounce buffer to virtiofsd. The total length of
these fuse args for the passed fuse request is about 10MB, so
copy_args_to_argbuf() invokes kmalloc() with a 10MB size parameter and
it triggers the warning in __alloc_pages():
if (WARN_ON_ONCE_GFP(order > MAX_PAGE_ORDER, gfp))
return NULL;
5) virtio_fs_enqueue_req() will retry the memory allocation in a
kworker, but it won't help, because kmalloc() will always return NULL
due to the abnormal size and finit_module() will hang forever.
A feasible solution is to limit the value of max_read for virtio-fs, so
the length passed to kmalloc() will be limited. However it will affect
the maximal read size for normal read. And for virtio-fs write initiated
from kernel, it has the similar problem but now there is no way to limit
fc->max_write in kernel.
So instead of limiting both the values of max_read and max_write in
kernel, introducing use_pages_for_kvec_io in fuse_conn and setting it as
true in virtiofs. When use_pages_for_kvec_io is enabled, fuse will use
pages instead of pointer to pass the KVEC_IO data.
After switching to pages for KVEC_IO data, these pages will be used for
DMA through virtio-fs. If these pages are backed by vmalloc(),
{flush|invalidate}_kernel_vmap_range() are necessary to flush or
invalidate the cache before the DMA operation. So add two new fields in
fuse_args_pages to record the base address of vmalloc area and the
condition indicating whether invalidation is needed. Perform the flush
in fuse_get_user_pages() for write operations and the invalidation in
fuse_release_user_pages() for read operations.
It may seem necessary to introduce another field in fuse_conn to
indicate that these KVEC_IO pages are used for DMA, However, considering
that virtio-fs is currently the only user of use_pages_for_kvec_io, just
reuse use_pages_for_kvec_io to indicate that these pages will be used
for DMA.
Fixes: a62a8ef9d9 ("virtio-fs: add virtiofs filesystem")
Signed-off-by: Hou Tao <houtao1@huawei.com>
Tested-by: Jingbo Xu <jefflexu@linux.alibaba.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Pull virtio updates from Michael Tsirkin:
"Several new features here:
- virtio-balloon supports new stats
- vdpa supports setting mac address
- vdpa/mlx5 suspend/resume as well as MKEY ops are now faster
- virtio_fs supports new sysfs entries for queue info
- virtio/vsock performance has been improved
And fixes, cleanups all over the place"
* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: (34 commits)
vsock/virtio: avoid queuing packets when intermediate queue is empty
vsock/virtio: refactor virtio_transport_send_pkt_work
fw_cfg: Constify struct kobj_type
vdpa/mlx5: Postpone MR deletion
vdpa/mlx5: Introduce init/destroy for MR resources
vdpa/mlx5: Rename mr_mtx -> lock
vdpa/mlx5: Extract mr members in own resource struct
vdpa/mlx5: Rename function
vdpa/mlx5: Delete direct MKEYs in parallel
vdpa/mlx5: Create direct MKEYs in parallel
MAINTAINERS: add virtio-vsock driver in the VIRTIO CORE section
virtio_fs: add sysfs entries for queue information
virtio_fs: introduce virtio_fs_put_locked helper
vdpa: Remove unused declarations
vdpa/mlx5: Parallelize VQ suspend/resume for CVQ MQ command
vdpa/mlx5: Small improvement for change_num_qps()
vdpa/mlx5: Keep notifiers during suspend but ignore
vdpa/mlx5: Parallelize device resume
vdpa/mlx5: Parallelize device suspend
vdpa/mlx5: Use async API for vq modify commands
...
Introduce sysfs entries to provide visibility to the multiple queues
used by the Virtio FS device. This enhancement allows users to query
information about these queues.
Specifically, add two sysfs entries:
1. Queue name: Provides the name of each queue (e.g. hiprio/requests.8).
2. CPU list: Shows the list of CPUs that can process requests for each
queue.
The CPU list feature is inspired by similar functionality in the block
MQ layer, which provides analogous sysfs entries for block devices.
These new sysfs entries will improve observability and aid in debugging
and performance tuning of Virtio FS devices.
Reviewed-by: Idan Zach <izach@nvidia.com>
Reviewed-by: Shai Malin <smalin@nvidia.com>
Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Message-Id: <20240825130716.9506-2-mgurtovoy@nvidia.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Introduce a new helper function virtio_fs_put_locked to encapsulate the
common pattern of releasing a virtio_fs reference while holding a lock.
The existing virtio_fs_put helper will be used to release a virtio_fs
reference while not holding a lock.
Also add an assertion in case the lock is not taken when it should.
Reviewed-by: Idan Zach <izach@nvidia.com>
Reviewed-by: Shai Malin <smalin@nvidia.com>
Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Message-Id: <20240825130716.9506-1-mgurtovoy@nvidia.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Virtiofs has its own queuing mechanism, but still requests are first queued
on fiq->pending to be immediately dequeued and queued onto the virtio
queue.
The queuing on fiq->pending is unnecessary and might even have some
performance impact due to being a contention point.
Forget requests are handled similarly.
Move the queuing of requests and forgets into the fiq->ops->*.
fuse_iqueue_ops are renamed to reflect the new semantics.
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Fixed-by: Jingbo Xu <jefflexu@linux.alibaba.com>
Reviewed-by: Jingbo Xu <jefflexu@linux.alibaba.com>
Tested-by: Peter-Jan Gootzen <pgootzen@nvidia.com>
Reviewed-by: Peter-Jan Gootzen <pgootzen@nvidia.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Currently, when the Virtio queue is full, a work item is scheduled
to execute in 1ms that retries adding the request to the queue.
This is a large amount of time on the scale on which a
virtio-fs device can operate. When using a DPU this is around
30-40us baseline without going to a remote server (4k, QD=1).
This patch changes the retrying behavior to immediately filling the
Virtio queue up again when a completion has been received.
This reduces the 99.9th percentile latencies in our tests by
60x and slightly increases the overall throughput, when using a
workload IO depth 2x the size of the Virtio queue and a
DPU-powered virtio-fs device (NVIDIA BlueField DPU).
Signed-off-by: Peter-Jan Gootzen <pgootzen@nvidia.com>
Reviewed-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Reviewed-by: Yoray Zack <yorayz@nvidia.com>
Message-Id: <20240517190435.152096-3-pgootzen@nvidia.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Currently, when the enqueueing of a request or forget operation fails
with -ENOMEM, the enqueueing is retried after a timeout. This patch
removes this behavior and treats -ENOMEM in these scenarios like any
other error. By bubbling up the error to user space in the case of a
request, and by dropping the operation in case of a forget. This
behavior matches that of the FUSE layer above, and also simplifies the
error handling. The latter will come in handy for upcoming patches that
optimize the retrying of operations in case of -ENOSPC.
Signed-off-by: Peter-Jan Gootzen <pgootzen@nvidia.com>
Reviewed-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Reviewed-by: Yoray Zack <yorayz@nvidia.com>
Message-Id: <20240517190435.152096-2-pgootzen@nvidia.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Pull virtio updates from Michael Tsirkin:
"Several new features here:
- virtio-net is finally supported in vduse
- virtio (balloon and mem) interaction with suspend is improved
- vhost-scsi now handles signals better/faster
And fixes, cleanups all over the place"
* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: (48 commits)
virtio-pci: Check if is_avq is NULL
virtio: delete vq in vp_find_vqs_msix() when request_irq() fails
MAINTAINERS: add Eugenio Pérez as reviewer
vhost-vdpa: Remove usage of the deprecated ida_simple_xx() API
vp_vdpa: don't allocate unused msix vectors
sound: virtio: drop owner assignment
fuse: virtio: drop owner assignment
scsi: virtio: drop owner assignment
rpmsg: virtio: drop owner assignment
nvdimm: virtio_pmem: drop owner assignment
wifi: mac80211_hwsim: drop owner assignment
vsock/virtio: drop owner assignment
net: 9p: virtio: drop owner assignment
net: virtio: drop owner assignment
net: caif: virtio: drop owner assignment
misc: nsm: drop owner assignment
iommu: virtio: drop owner assignment
drm/virtio: drop owner assignment
gpio: virtio: drop owner assignment
firmware: arm_scmi: virtio: drop owner assignment
...
This commit creates a multi-queue mapping at device bring-up.
The driver first attempts to use the existing MSI-X interrupt
affinities (previously disabled), and if not present, will distribute
the request queues evenly over the CPUs.
If the latter fails as well, all CPUs are mapped to request queue zero.
When a request is handed from FUSE to the virtio-fs device driver, the
driver will use the current CPU to index into the multi-queue mapping
and determine the optimal request queue to use.
We measured the performance of this patch with the fio benchmarking
tool, increasing the number of queues results in a significant speedup
for both read and write operations, demonstrating the effectiveness
of multi-queue support.
Host:
- Dell PowerEdge R760
- CPU: Intel(R) Xeon(R) Gold 6438M, 128 cores
- VM: KVM with 32 cores
Virtio-fs device:
- BlueField-3 DPU
- CPU: ARM Cortex-A78AE, 16 cores
- One thread per queue, each busy polling on one request queue
- Each queue is 1024 descriptors deep
Workload:
- fio, sequential read or write, ioengine=libaio, numjobs=32,
4GiB file per job, iodepth=8, bs=256KiB, runtime=30s
Performance Results:
+===========================+==========+===========+
| Number of queues | Fio read | Fio write |
+===========================+==========+===========+
| 1 request queue (GiB/s) | 6.1 | 4.6 |
+---------------------------+----------+-----------+
| 8 request queues (GiB/s) | 25.8 | 10.3 |
+---------------------------+----------+-----------+
| 16 request queues (GiB/s) | 30.9 | 19.5 |
+---------------------------+----------+-----------+
| 32 request queue (GiB/s) | 33.2 | 22.6 |
+---------------------------+----------+-----------+
| Speedup | 5.5x | 5x |
+---------------=-----------+----------+-----------+
Signed-off-by: Peter-Jan Gootzen <pgootzen@nvidia.com>
Signed-off-by: Yoray Zack <yorayz@nvidia.com>
Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Virtio-fs devices might allocate significant resources to virtio queues
such as CPU cores that busy poll on the queue. The device indicates how
many request queues it can support and the driver should initialize the
number of queues that they want to utilize.
In this patch we limit the number of initialized request queues to the
number of CPUs, to limit the resource consumption on the device-side
and to prepare for the upcoming multi-queue patch.
Signed-off-by: Peter-Jan Gootzen <pgootzen@nvidia.com>
Signed-off-by: Yoray Zack <yorayz@nvidia.com>
Suggested-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Reviewed-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
The internal tag string doesn't contain a newline. Append one when
emitting the tag via sysfs.
[Stefan] Orthogonal to the newline issue, sysfs_emit(buf, "%s", fs->tag) is
needed to prevent format string injection.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Fixes: a8f62f50b4 ("virtiofs: export filesystem tags through sysfs")
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Pull fuse updates from Miklos Szeredi:
- Add passthrough mode for regular file I/O.
This allows performing read and write (also via memory maps) on a
backing file without incurring the overhead of roundtrips to
userspace. For now this is only allowed to privileged servers, but
this limitation will go away in the future (Amir Goldstein)
- Fix interaction of direct I/O mode with memory maps (Bernd Schubert)
- Export filesystem tags through sysfs for virtiofs (Stefan Hajnoczi)
- Allow resending queued requests for server crash recovery (Zhao Chen)
- Misc fixes and cleanups
* tag 'fuse-update-6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse: (38 commits)
fuse: get rid of ff->readdir.lock
fuse: remove unneeded lock which protecting update of congestion_threshold
fuse: Fix missing FOLL_PIN for direct-io
fuse: remove an unnecessary if statement
fuse: Track process write operations in both direct and writethrough modes
fuse: Use the high bit of request ID for indicating resend requests
fuse: Introduce a new notification type for resend pending requests
fuse: add support for explicit export disabling
fuse: __kuid_val/__kgid_val helpers in fuse_fill_attr_from_inode()
fuse: fix typo for fuse_permission comment
fuse: Convert fuse_writepage_locked to take a folio
fuse: Remove fuse_writepage
virtio_fs: remove duplicate check if queue is broken
fuse: use FUSE_ROOT_ID in fuse_get_root_inode()
fuse: don't unhash root
fuse: fix root lookup with nonzero generation
fuse: replace remaining make_bad_inode() with fuse_make_bad()
virtiofs: drop __exit from virtio_fs_sysfs_exit()
fuse: implement passthrough for mmap
fuse: implement splice read/write passthrough
...
virtqueue_enable_cb() will call virtqueue_poll() which will check if
queue is broken at beginning, so remove the virtqueue_is_broken() call
Signed-off-by: Li RongQing <lirongqing@baidu.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Alyssa Ross <hi@alyssa.is> requested that virtiofs notifies userspace
when filesytems become available. This can be used to detect when a
filesystem with a given tag is hotplugged, for example. uevents allow
userspace to detect changes without resorting to polling.
The tag is included as a uevent property so it's easy for userspace to
identify the filesystem in question even when the sysfs directory goes
away during removal.
Here are example uevents:
# udevadm monitor -k -p
KERNEL[111.113221] add /fs/virtiofs/2 (virtiofs)
ACTION=add
DEVPATH=/fs/virtiofs/2
SUBSYSTEM=virtiofs
TAG=test
KERNEL[165.527167] remove /fs/virtiofs/2 (virtiofs)
ACTION=remove
DEVPATH=/fs/virtiofs/2
SUBSYSTEM=virtiofs
TAG=test
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
The virtiofs filesystem is mounted using a "tag" which is exported by
the virtiofs device:
# mount -t virtiofs <tag> /mnt
The virtiofs driver knows about all the available tags but these are
currently not exported to user space.
People have asked for these tags to be exported to user space. Most
recently Lennart Poettering has asked for it as he wants to scan the
tags and mount virtiofs automatically in certain cases.
https://gitlab.com/virtio-fs/virtiofsd/-/issues/128
This patch exports tags at /sys/fs/virtiofs/<N>/tag where N is the id of
the virtiofs device. The filesystem tag can be obtained by reading this
"tag" file.
There is also a symlink at /sys/fs/virtiofs/<N>/device that points to
the virtiofs device that exports this tag.
This patch converts the existing struct virtio_fs into a full kobject.
It already had a refcount so it's an easy change. The virtio_fs objects
can then be exposed in a kset at /sys/fs/virtiofs/. Note that virtio_fs
objects may live slightly longer than we wish for them to be exposed to
userspace, so kobject_del() is called explicitly when the underlying
virtio_device is removed. The virtio_fs object is freed when all
references are dropped (e.g. active mounts) but disappears as soon as
the virtiofs device is gone.
Originally-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Newlines in virtiofs tags are awkward for users and potential vectors
for string injection attacks.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
When multiple processes mmap() a dax file, then at some point,
a process issues a 'load' and consumes a hwpoison, the process
receives a SIGBUS with si_code = BUS_MCEERR_AR and with si_lsb
set for the poison scope. Soon after, any other process issues
a 'load' to the poisoned page (that is unmapped from the kernel
side by memory_failure), it receives a SIGBUS with
si_code = BUS_ADRERR and without valid si_lsb.
This is confusing to user, and is different from page fault due
to poison in RAM memory, also some helpful information is lost.
Channel dax backend driver's poison detection to the filesystem
such that instead of reporting VM_FAULT_SIGBUS, it could report
VM_FAULT_HWPOISON.
If user level block IO syscalls fail due to poison, the errno will
be converted to EIO to maintain block API consistency.
Signed-off-by: Jane Chu <jane.chu@oracle.com>
Link: https://lore.kernel.org/r/20230615181325.1327259-2-jane.chu@oracle.com
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
Pull virtio updates from Michael Tsirkin:
"virtio,vdpa,qemu_fw_cfg: features, cleanups, and fixes.
- partial support for < MAX_ORDER - 1 granularity for virtio-mem
- driver_override for vdpa
- sysfs ABI documentation for vdpa
- multiqueue config support for mlx5 vdpa
- and misc fixes, cleanups"
* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: (42 commits)
vdpa/mlx5: Fix tracking of current number of VQs
vdpa/mlx5: Fix is_index_valid() to refer to features
vdpa: Protect vdpa reset with cf_mutex
vdpa: Avoid taking cf_mutex lock on get status
vdpa/vdpa_sim_net: Report max device capabilities
vdpa: Use BIT_ULL for bit operations
vdpa/vdpa_sim: Configure max supported virtqueues
vdpa/mlx5: Report max device capabilities
vdpa: Support reporting max device capabilities
vdpa/mlx5: Restore cur_num_vqs in case of failure in change_num_qps()
vdpa: Add support for returning device configuration information
vdpa/mlx5: Support configuring max data virtqueue
vdpa/mlx5: Fix config_attr_mask assignment
vdpa: Allow to configure max data virtqueues
vdpa: Read device configuration only if FEATURES_OK
vdpa: Sync calls set/get config/status with cf_mutex
vdpa/mlx5: Distribute RX virtqueues in RQT object
vdpa: Provide interface to read driver features
vdpa: clean up get_config_size ret value handling
virtio_ring: mark ring unused on error
...
This will enable cleanups down the road.
The idea is to disable cbs, then add "flush_queued_cbs" callback
as a parameter, this way drivers can flush any work
queued after callbacks have been disabled.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Link: https://lore.kernel.org/r/20211013105226.20225-1-mst@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Pull dax and libnvdimm updates from Dan Williams:
"The bulk of this is a rework of the dax_operations API after
discovering the obstacles it posed to the work-in-progress DAX+reflink
support for XFS and other copy-on-write filesystem mechanics.
Primarily the need to plumb a block_device through the API to handle
partition offsets was a sticking point and Christoph untangled that
dependency in addition to other cleanups to make landing the
DAX+reflink support easier.
The DAX_PMEM_COMPAT option has been around for 4 years and not only
are distributions shipping userspace that understand the current
configuration API, but some are not even bothering to turn this option
on anymore, so it seems a good time to remove it per the deprecation
schedule. Recall that this was added after the device-dax subsystem
moved from /sys/class/dax to /sys/bus/dax for its sysfs organization.
All recent functionality depends on /sys/bus/dax.
Some other miscellaneous cleanups and reflink prep patches are
included as well.
Summary:
- Simplify the dax_operations API:
- Eliminate bdev_dax_pgoff() in favor of the filesystem
maintaining and applying a partition offset to all its DAX iomap
operations.
- Remove wrappers and device-mapper stacked callbacks for
->copy_from_iter() and ->copy_to_iter() in favor of moving
block_device relative offset responsibility to the
dax_direct_access() caller.
- Remove the need for an @bdev in filesystem-DAX infrastructure
- Remove unused uio helpers copy_from_iter_flushcache() and
copy_mc_to_iter() as only the non-check_copy_size() versions are
used for DAX.
- Prepare XFS for the pending (next merge window) DAX+reflink support
- Remove deprecated DEV_DAX_PMEM_COMPAT support
- Cleanup a straggling misuse of the GUID api"
* tag 'libnvdimm-for-5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (38 commits)
iomap: Fix error handling in iomap_zero_iter()
ACPI: NFIT: Import GUID before use
dax: remove the copy_from_iter and copy_to_iter methods
dax: remove the DAXDEV_F_SYNC flag
dax: simplify dax_synchronous and set_dax_synchronous
uio: remove copy_from_iter_flushcache() and copy_mc_to_iter()
iomap: turn the byte variable in iomap_zero_iter into a ssize_t
memremap: remove support for external pgmap refcounts
fsdax: don't require CONFIG_BLOCK
iomap: build the block based code conditionally
dax: fix up some of the block device related ifdefs
fsdax: shift partition offset handling into the file systems
dax: return the partition offset from fs_dax_get_by_bdev
iomap: add a IOMAP_DAX flag
xfs: pass the mapping flags to xfs_bmbt_to_iomap
xfs: use xfs_direct_write_iomap_ops for DAX zeroing
xfs: move dax device handling into xfs_{alloc,free}_buftarg
ext4: cleanup the dax handling in ext4_fill_super
ext2: cleanup the dax handling in ext2_fill_super
fsdax: decouple zeroing from the iomap buffered I/O code
...
These methods indirect the actual DAX read/write path. In the end pmem
uses magic flush and mc safe variants and fuse and dcssblk use plain ones
while device mapper picks redirects to the underlying device.
Add set_dax_nocache() and set_dax_nomc() APIs to control which copy
routines are used to remove indirect call from the read/write fast path
as well as a lot of boilerplate code.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Vivek Goyal <vgoyal@redhat.com> [virtiofs]
Link: https://lore.kernel.org/r/20211215084508.435401-5-hch@lst.de
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
We add 'always', 'never', and 'inode' (default). '-o dax' continues to
operate the same which is equivalent to 'always'.
The following behavior is consistent with that on ext4/xfs:
- The default behavior (when neither '-o dax' nor
'-o dax=always|never|inode' option is specified) is equal to 'inode'
mode, while 'dax=inode' won't be printed among the mount option list.
- The 'inode' mode is only advisory. It will silently fallback to 'never'
mode if fuse server doesn't support that.
Also noted that by the time of this commit, 'inode' mode is actually equal
to 'always' mode, before the per inode DAX flag is introduced in the
following patch.
Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com>
Reviewed-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Always null terminate fsvq->name.
Reported-by: kernel test robot <lkp@intel.com>
Fixes: b43b7e81eb ("virtiofs: provide a helper function for virtqueue initialization")
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
1. call fuse_mount_destroy() for open coded variants
2. before deactivate_locked_super() don't need fuse_mount destruction since
that will now be done (if ->s_fs_info is not cleared)
3. rearrange fuse_mount setup in fuse_get_tree_submount() so that the
regular pattern can be used
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
The ->put_super callback is called from generic_shutdown_super() in case of
a fully initialized sb. This is called from kill_***_super(), which is
called from ->kill_sb instances.
Fuse uses ->put_super to destroy the fs specific fuse_mount and drop the
reference to the fuse_conn, while it does the same on each error case
during sb setup.
This patch moves the destruction from fuse_put_super() to
fuse_mount_destroy(), called at the end of all ->kill_sb instances. A
follup patch will clean up the error paths.
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Checking "fm" works because currently sb->s_fs_info is cleared on error
paths; however, sb->s_root is what generic_shutdown_super() checks to
determine whether the sb was fully initialized or not.
This change will allow cleanup of sb setup error paths.
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
The creation of a submount is open-coded in fuse_dentry_automount().
This brings a lot of complexity and we recently had to fix bugs
because we weren't setting SB_BORN or because we were unlocking
sb->s_umount before sb was fully configured. Most of these could
have been avoided by using the mount API instead of open-coding.
Basically, this means coming up with a proper ->get_tree()
implementation for submounts and call vfs_get_tree(), or better
fc_mount().
The creation of the superblock for submounts is quite different from
the root mount. Especially, it doesn't require to allocate a FUSE
filesystem context, nor to parse parameters.
Introduce a dedicated context ops for submounts to make this clear.
This is just a placeholder for now, fuse_get_tree_submount() will
be populated in a subsequent patch.
Only visible change is that we stop allocating/freeing a useless FUSE
filesystem context with submounts.
Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Even if POSIX doesn't mandate it, linux users legitimately expect sync() to
flush all data and metadata to physical storage when it is located on the
same system. This isn't happening with virtiofs though: sync() inside the
guest returns right away even though data still needs to be flushed from
the host page cache.
This is easily demonstrated by doing the following in the guest:
$ dd if=/dev/zero of=/mnt/foo bs=1M count=5K ; strace -T -e sync sync
5120+0 records in
5120+0 records out
5368709120 bytes (5.4 GB, 5.0 GiB) copied, 5.22224 s, 1.0 GB/s
sync() = 0 <0.024068>
and start the following in the host when the 'dd' command completes
in the guest:
$ strace -T -e fsync /usr/bin/sync virtiofs/foo
fsync(3) = 0 <10.371640>
There are no good reasons not to honor the expected behavior of sync()
actually: it gives an unrealistic impression that virtiofs is super fast
and that data has safely landed on HW, which isn't the case obviously.
Implement a ->sync_fs() superblock operation that sends a new FUSE_SYNCFS
request type for this purpose. Provision a 64-bit placeholder for possible
future extensions. Since the file server cannot handle the wait == 0 case,
we skip it to avoid a gratuitous roundtrip. Note that this is
per-superblock: a FUSE_SYNCFS is send for the root mount and for each
submount.
Like with FUSE_FSYNC and FUSE_FSYNCDIR, lack of support for FUSE_SYNCFS in
the file server is treated as permanent success. This ensures
compatibility with older file servers: the client will get the current
behavior of sync() not being propagated to the file server.
Note that such an operation allows the file server to DoS sync(). Since a
typical FUSE file server is an untrusted piece of software running in
userspace, this is disabled by default. Only enable it with virtiofs for
now since virtiofsd is supposedly trusted by the guest kernel.
Reported-by: Robert Krawitz <rlk@redhat.com>
Signed-off-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
get_user_ns() is done twice (once in virtio_fs_get_tree() and once in
fuse_conn_init()), resulting in a reference leak.
Also looks better to use fsc->user_ns (which *should* be the
current_user_ns() at this point).
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
