fix #29429936

commit 9d40b85bb46a99bc95dad3a07787da93b0a018e9 upstream

AMD Zen 2 introduces a new RDPRU instruction which is used to give
access to some processor registers that are typically only accessible
when the privilege level is zero.

ECX is used as the implicit register to specify which register to read.
RDPRU places the specified register’s value into EDX:EAX.

For example, the RDPRU instruction can be used to read MPERF and APERF
at CPL > 0.

Add the feature bit so it is visible in /proc/cpuinfo.

Details are available in the AMD64 Architecture Programmer’s Manual:
https://www.amd.com/system/files/TechDocs/24594.pdfSigned-off-by: NBabu Moger <babu.moger@amd.com>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Cc: Aaron Lewis <aaronlewis@google.com>
Cc: ak@linux.intel.com
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org>
Cc: robert.hu@linux.intel.com
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Thomas Hellstrom <thellstrom@vmware.com>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20191007204839.5727.10803.stgit@localhost.localdomainSigned-off-by: NArtie Ding <artie.ding@linux.alibaba.com>
Acked-by: NCaspar Zhang <caspar@linux.alibaba.com>

fix #29455282

commit c8980e1980ccdc2229aa2218d532ddc62e0aabe5 upstream

The patch "ext4: make dioread_nolock the default" (244adf6426ee) causes
generic/422 to fail when run in kvm-xfstests' ext3conv test case.  This
applies both the dioread_nolock and nodelalloc mount options, a
combination not previously tested by kvm-xfstests.  The failure occurs
because the dioread_nolock code path splits a previously fallocated
multiblock extent into a series of single block extents when overwriting
a portion of that extent.  That causes allocation of an extent tree leaf
node and a reshuffling of extents.  Once writeback is completed, the
individual extents are recombined into a single extent, the extent is
moved again, and the leaf node is deleted.  The difference in block
utilization before and after writeback due to the leaf node triggers the
failure.

The original reason for this behavior was to avoid ENOSPC when handling
I/O completions during writeback in the dioread_nolock code paths when
delayed allocation is disabled.  It may no longer be necessary, because
code was added in the past to reserve extra space to solve this problem
when delayed allocation is enabled, and this code may also apply when
delayed allocation is disabled.  Until this can be verified, don't use
the dioread_nolock code paths if delayed allocation is disabled.
Signed-off-by: NEric Whitney <enwlinux@gmail.com>
Link: https://lore.kernel.org/r/20200319150028.24592-1-enwlinux@gmail.comSigned-off-by: NTheodore Ts'o <tytso@mit.edu>
Signed-off-by: NJeffle Xu <jefflexu@linux.alibaba.com>
Reviewed-by: NJoseph Qi <joseph.qi@linux.alibaba.com>

fix #29535320

In __nvme_poll(), nvme_complete_cqes() should also been protected
by nvmeq->cq_lock.

Fixes: 0d326c85dba5 ("nvme: provide optimized poll function for separate poll queues")
Signed-off-by: NXiaoguang Wang <xiaoguang.wang@linux.alibaba.com>
Reviewed-by: NJoseph Qi <joseph.qi@linux.alibaba.com>

fix #29056122

commit 'fbb2f06e' ("pvpanic: add crash loaded event") introduce new
pvpanic event 'PVPANIC_CRASH_LOADED', it make the qemu on host can get
info that if the guest already handle the panic by kdump or not.

But if the guest enabled the kdump, it will not post the panic event by
default unless the parameter 'crash_kexec_post_notifiers' is given.
So, its better to set the default value of this parameter to true, to
avoid it missed in case of kdump enabled.

If user want disable the event notification, the parameter
'crash_kexec_post_notifiers=N' should be given.
Signed-off-by: NShile Zhang <shile.zhang@linux.alibaba.com>
Acked-by: NJoseph Qi <joseph.qi@linux.alibaba.com>

task #28910367
These two are added to alinux recently, update configs to reflect
them.
Signed-off-by: NLiu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: NJoseph Qi <joseph.qi@linux.alibaba.com>

fix #29495487

commit 6abff1b9f7b8884a46b7bd80b49e7af0b5625aeb upstream.

nvme_update_formats may fail to revalidate the namespace and
attempt to remove the namespace. This may lead to a deadlock
as nvme_ns_remove will attempt to acquire the subsystem lock
which is already acquired by the passthru command with effects.

Move the invalid namepsace removal to after the passthru command
releases the subsystem lock.
Reported-by: NJudy Brock <judy.brock@samsung.com>
Signed-off-by: NSagi Grimberg <sagi@grimberg.me>
Signed-off-by: NJoseph Qi <joseph.qi@linux.alibaba.com>
Reviewed-by: NBaolin Wang <baolin.wang@linux.alibaba.com>
Acked-by: NXiaoguang Wang <xiaoguang.wang@linux.alibaba.com>
Reviewed-by: NJiufei Xue <jiufei.xue@linux.alibaba.com>

task #29355864

Disable the following builtin modules, which is needless for modern
kernel:
 - CONFIG_VIRTIO_BLK_SCSI=y
 - CONFIG_SYSCTL_SYSCALL=y
 - CONFIG_ISA_BUS=y
 - CONFIG_NET_VENDOR_CADENCE=y
 - CONFIG_NET_VENDOR_CORTINA=y
 - CONFIG_NET_VENDOR_I825XX=y
 - CONFIG_NET_VENDOR_NETERION=y
 - CONFIG_NET_VENDOR_NI=y
 - CONFIG_NET_VENDOR_PACKET_ENGINES=y
 - CONFIG_NET_VENDOR_SOCIONEXT=y
 - CONFIG_XFS_RT=y
 - CONFIG_DEBUG_SG=y
 - CONFIG_DEBUG_NOTIFIERS=y
 - CONFIG_DEBUG_CREDENTIALS=y
Signed-off-by: NShile Zhang <shile.zhang@linux.alibaba.com>
Acked-by: NJoseph Qi <joseph.qi@linux.alibaba.com>
Acked-by: NDust Li <dust.li@linux.alibaba.com>

task #28910367
Rather than explicitly specifying "-o
default_permissions,allow_other", virtiofs can set some default values
for them.

With this, we can simply do
"mount -t virtio_fs atest /mnt/test/ -otag=myfs-1,dax".
Signed-off-by: NLiu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: NJoseph Qi <joseph.qi@linux.alibaba.com>

task #28910367
virtio-fs will need to use it from outside fs/fuse/dev.c.
Make the symbol visible.
Signed-off-by: NLiu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: NJoseph Qi <joseph.qi@linux.alibaba.com>

task #28910367
commit 519525fa47b5a8155f0b203e49a3a6a2319f75ae upstream

Allow fuse to pass RENAME_WHITEOUT to fuse server.  Overlayfs on top of
virtiofs uses RENAME_WHITEOUT.

Without this patch renaming a directory in overlayfs (dir is on lower)
fails with -EINVAL. With this patch it works.
Signed-off-by: NVivek Goyal <vgoyal@redhat.com>
Signed-off-by: NMiklos Szeredi <mszeredi@redhat.com>
(cherry picked from commit 519525fa47b5a8155f0b203e49a3a6a2319f75ae)
Signed-off-by: NLiu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: NJoseph Qi <joseph.qi@linux.alibaba.com>

task #28910367
commit 724c15a43e2c7ac26e2d07abef99191162498fa9 upstream

While we wait for queue to finish draining, use completions instead of
usleep_range(). This is better way of waiting for event.
Signed-off-by: NVivek Goyal <vgoyal@redhat.com>
Reviewed-by: NStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: NMiklos Szeredi <mszeredi@redhat.com>
(cherry picked from commit 724c15a43e2c7ac26e2d07abef99191162498fa9)
Signed-off-by: NLiu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: NJoseph Qi <joseph.qi@linux.alibaba.com>

task #28910367
commit 1efcf39eb627573f8d543ea396cf36b0651b1e56 upstream

We are sending whole of virtio_fs_forget struct to the other end over
virtqueue. Other end does not need to see elements like "struct list".
That's internal detail of guest kernel. Fix it.
Signed-off-by: NVivek Goyal <vgoyal@redhat.com>
Reviewed-by: NStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: NMiklos Szeredi <mszeredi@redhat.com>
(cherry picked from commit 1efcf39eb627573f8d543ea396cf36b0651b1e56)
Signed-off-by: NLiu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: NJoseph Qi <joseph.qi@linux.alibaba.com>

task #28910367
commit 58ada94f95f71d4f73197ab0e9603dbba6e47fe3 upstream

Currently we are duplicating logic to send forgets at two
places. Consolidate the code by calling one helper function.

This also uses virtqueue_add_outbuf() instead of
virtqueue_add_sgs(). Former is simpler to call.
Signed-off-by: NVivek Goyal <vgoyal@redhat.com>
Reviewed-by: NStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: NMiklos Szeredi <mszeredi@redhat.com>
(cherry picked from commit 58ada94f95f71d4f73197ab0e9603dbba6e47fe3)
Signed-off-by: NLiu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: NJoseph Qi <joseph.qi@linux.alibaba.com>

task #28910367
commit 00929447f5758c4f64c74d0a4b40a6eb3d9df0e3 upstream

There expect the 'static' keyword to come first in a declaration, and we
get warnings like this with "make W=1":

fs/fuse/virtio_fs.c:687:1: warning: 'static' is not at beginning of declaration [-Wold-style-declaration]
fs/fuse/virtio_fs.c:692:1: warning: 'static' is not at beginning of declaration [-Wold-style-declaration]
fs/fuse/virtio_fs.c:1029:1: warning: 'static' is not at beginning of declaration [-Wold-style-declaration]
Signed-off-by: NYueHaibing <yuehaibing@huawei.com>
Reviewed-by: NStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: NMiklos Szeredi <mszeredi@redhat.com>
(cherry picked from commit 00929447f5758c4f64c74d0a4b40a6eb3d9df0e3)
Signed-off-by: NLiu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: NJoseph Qi <joseph.qi@linux.alibaba.com>

task #28910367
commit 80da5a809d193c60d090cbdf4fe316781bc07965 upstream

Fixes gcc '-Wunused-but-set-variable' warning:

fs/fuse/virtio_fs.c: In function virtio_fs_wake_pending_and_unlock:
fs/fuse/virtio_fs.c:983:20: warning: variable fc set but not used [-Wunused-but-set-variable]

It is not used since commit 7ee1e2e631db ("virtiofs: No need to check
fpq->connected state")
Reported-by: NHulk Robot <hulkci@huawei.com>
Signed-off-by: Nzhengbin <zhengbin13@huawei.com>
Signed-off-by: NMiklos Szeredi <mszeredi@redhat.com>
Reviewed-by: NJoseph Qi <joseph.qi@linux.alibaba.com>
Signed-off-by: NLiu Bo <bo.liu@linux.alibaba.com>

task #28910367
commit a9bfd9dd3417561d06c81de04f6d6c1e0c9b3d44 upstream

If regular request queue gets full, currently we sleep for a bit and
retrying submission in submitter's context. This assumes submitter is not
holding any spin lock. But this assumption is not true for background
requests. For background requests, we are called with fc->bg_lock held.

This can lead to deadlock where one thread is trying submission with
fc->bg_lock held while request completion thread has called
fuse_request_end() which tries to acquire fc->bg_lock and gets blocked. As
request completion thread gets blocked, it does not make further progress
and that means queue does not get empty and submitter can't submit more
requests.

To solve this issue, retry submission with the help of a worker, instead of
retrying in submitter's context. We already do this for hiprio/forget
requests.
Reported-by: NChirantan Ekbote <chirantan@chromium.org>
Signed-off-by: NVivek Goyal <vgoyal@redhat.com>
Signed-off-by: NMiklos Szeredi <mszeredi@redhat.com>
(cherry picked from commit a9bfd9dd3417561d06c81de04f6d6c1e0c9b3d44)
Signed-off-by: NLiu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: NJoseph Qi <joseph.qi@linux.alibaba.com>

task #28910367

commit c17ea009610366146ec409fd6dc277e0f2510b10 upstream

If virtqueue is full, we put forget requests on a list and these forgets
are dispatched later using a worker. As of now we don't count these forgets
in fsvq->in_flight variable. This means when queue is being drained, we
have to have special logic to first drain these pending requests and then
wait for fsvq->in_flight to go to zero.

By counting pending forgets in fsvq->in_flight, we can get rid of special
logic and just wait for in_flight to go to zero. Worker thread will kick
and drain all the forgets anyway, leading in_flight to zero.

I also need similar logic for normal request queue in next patch where I am
about to defer request submission in the worker context if queue is full.

This simplifies the code a bit.

Also add two helper functions to inc/dec in_flight. Decrement in_flight
helper will later used to call completion when in_flight reaches zero.
Signed-off-by: NVivek Goyal <vgoyal@redhat.com>
Signed-off-by: NMiklos Szeredi <mszeredi@redhat.com>
(cherry picked from commit c17ea009610366146ec409fd6dc277e0f2510b10)
Signed-off-by: NLiu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: NJoseph Qi <joseph.qi@linux.alibaba.com>

task #28910367
commit 5dbe190f341206a7896f7e40c1e3a36933d812f3 upstream

FR_SENT flag should be set when request has been sent successfully sent
over virtqueue. This is used by interrupt logic to figure out if interrupt
request should be sent or not.

Also add it to fqp->processing list after sending it successfully.
Signed-off-by: NVivek Goyal <vgoyal@redhat.com>
Signed-off-by: NMiklos Szeredi <mszeredi@redhat.com>
Signed-off-by: NLiu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: NJoseph Qi <joseph.qi@linux.alibaba.com>

task #28910367
commit 7ee1e2e631dbf0ff0df2a67a1e01ba3c1dce7a46 upstream

In virtiofs we keep per queue connected state in virtio_fs_vq->connected
and use that to end request if queue is not connected. And virtiofs does
not even touch fpq->connected state.

We probably need to merge these two at some point of time. For now,
simplify the code a bit and do not worry about checking state of
fpq->connected.
Signed-off-by: NVivek Goyal <vgoyal@redhat.com>
Signed-off-by: NMiklos Szeredi <mszeredi@redhat.com>
Reviewed-by: NJoseph Qi <joseph.qi@linux.alibaba.com>
Signed-off-by: NLiu Bo <bo.liu@linux.alibaba.com>

task #28910367
commit 51fecdd2555b3e0e05a78d30093c638d164a32f9 upstream

Submission context can hold some locks which end request code tries to hold
again and deadlock can occur. For example, fc->bg_lock. If a background
request is being submitted, it might hold fc->bg_lock and if we could not
submit request (because device went away) and tried to end request, then
deadlock happens. During testing, I also got a warning from deadlock
detection code.

So put requests on a list and end requests from a worker thread.

I got following warning from deadlock detector.

[  603.137138] WARNING: possible recursive locking detected
[  603.137142] --------------------------------------------
[  603.137144] blogbench/2036 is trying to acquire lock:
[  603.137149] 00000000f0f51107 (&(&fc->bg_lock)->rlock){+.+.}, at: fuse_request_end+0xdf/0x1c0 [fuse]
[  603.140701]
[  603.140701] but task is already holding lock:
[  603.140703] 00000000f0f51107 (&(&fc->bg_lock)->rlock){+.+.}, at: fuse_simple_background+0x92/0x1d0 [fuse]
[  603.140713]
[  603.140713] other info that might help us debug this:
[  603.140714]  Possible unsafe locking scenario:
[  603.140714]
[  603.140715]        CPU0
[  603.140716]        ----
[  603.140716]   lock(&(&fc->bg_lock)->rlock);
[  603.140718]   lock(&(&fc->bg_lock)->rlock);
[  603.140719]
[  603.140719]  *** DEADLOCK ***
Signed-off-by: NVivek Goyal <vgoyal@redhat.com>
Signed-off-by: NMiklos Szeredi <mszeredi@redhat.com>
Reviewed-by: NJoseph Qi <joseph.qi@linux.alibaba.com>
Signed-off-by: NLiu Bo <bo.liu@linux.alibaba.com>

task #28910367
commit 112e72373d1f60f1e4558d0a7f0de5da39a1224d upstream

We have been calling it virtio_fs and even file name is virtio_fs.c. Module
name is virtio_fs.ko but when registering file system user is supposed to
specify filesystem type as "virtiofs".

Masayoshi Mizuma reported that he specified filesytem type as "virtio_fs"
and got this warning on console.

  ------------[ cut here ]------------
  request_module fs-virtio_fs succeeded, but still no fs?
  WARNING: CPU: 1 PID: 1234 at fs/filesystems.c:274 get_fs_type+0x12c/0x138
  Modules linked in: ... virtio_fs fuse virtio_net net_failover ...
  CPU: 1 PID: 1234 Comm: mount Not tainted 5.4.0-rc1 #1

So looks like kernel could find the module virtio_fs.ko but could not find
filesystem type after that.

It probably is better to rename module name to virtiofs.ko so that above
warning goes away in case user ends up specifying wrong fs name.
Reported-by: NMasayoshi Mizuma <msys.mizuma@gmail.com>
Suggested-by: NStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: NVivek Goyal <vgoyal@redhat.com>
Tested-by: NMasayoshi Mizuma <m.mizuma@jp.fujitsu.com>
Reviewed-by: NStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: NMiklos Szeredi <mszeredi@redhat.com>
(cherry picked from commit 112e72373d1f60f1e4558d0a7f0de5da39a1224d)
Signed-off-by: NLiu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: NJoseph Qi <joseph.qi@linux.alibaba.com>

task #28910367
commit a62a8ef9d97da23762a588592c8b8eb50a8deb6a upstream

Add a basic file system module for virtio-fs.  This does not yet contain
shared data support between host and guest or metadata coherency speedups.
However it is already significantly faster than virtio-9p.

Design Overview
===============

With the goal of designing something with better performance and local file
system semantics, a bunch of ideas were proposed.

 - Use fuse protocol (instead of 9p) for communication between guest and
   host.  Guest kernel will be fuse client and a fuse server will run on
   host to serve the requests.

 - For data access inside guest, mmap portion of file in QEMU address space
   and guest accesses this memory using dax.  That way guest page cache is
   bypassed and there is only one copy of data (on host).  This will also
   enable mmap(MAP_SHARED) between guests.

 - For metadata coherency, there is a shared memory region which contains
   version number associated with metadata and any guest changing metadata
   updates version number and other guests refresh metadata on next access.
   This is yet to be implemented.

How virtio-fs differs from existing approaches
==============================================

The unique idea behind virtio-fs is to take advantage of the co-location of
the virtual machine and hypervisor to avoid communication (vmexits).

DAX allows file contents to be accessed without communication with the
hypervisor.  The shared memory region for metadata avoids communication in
the common case where metadata is unchanged.

By replacing expensive communication with cheaper shared memory accesses,
we expect to achieve better performance than approaches based on network
file system protocols.  In addition, this also makes it easier to achieve
local file system semantics (coherency).

These techniques are not applicable to network file system protocols since
the communications channel is bypassed by taking advantage of shared memory
on a local machine.  This is why we decided to build virtio-fs rather than
focus on 9P or NFS.

Caching Modes
=============

Like virtio-9p, different caching modes are supported which determine the
coherency level as well.  The “cache=FOO” and “writeback” options control
the level of coherence between the guest and host filesystems.

 - cache=none
   metadata, data and pathname lookup are not cached in guest.  They are
   always fetched from host and any changes are immediately pushed to host.

 - cache=always
   metadata, data and pathname lookup are cached in guest and never expire.

 - cache=auto
   metadata and pathname lookup cache expires after a configured amount of
   time (default is 1 second).  Data is cached while the file is open
   (close to open consistency).

 - writeback/no_writeback
   These options control the writeback strategy.  If writeback is disabled,
   then normal writes will immediately be synchronized with the host fs.
   If writeback is enabled, then writes may be cached in the guest until
   the file is closed or an fsync(2) performed.  This option has no effect
   on mmap-ed writes or writes going through the DAX mechanism.
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: NVivek Goyal <vgoyal@redhat.com>
Acked-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMiklos Szeredi <mszeredi@redhat.com>

(cherry picked from commit a62a8ef9d97da23762a588592c8b8eb50a8deb6a)
[Liubo: given that 4.19 lacks the support of fs_context to parse mount
option, here I just change it back to the 4.19 way, so we still use -o
tag=myfs-1 to get virtiofs mount.]
Signed-off-by: NLiu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: NJoseph Qi <joseph.qi@linux.alibaba.com>

task #28910367
commit 2d1d25d0a224dcd2021004d52342fc1727ccd85f upstream

Add information about the new "virtiofs" file system.
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: NMiklos Szeredi <mszeredi@redhat.com>
Signed-off-by: NLiu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: NJoseph Qi <joseph.qi@linux.alibaba.com>

task #28910367
commit c4bb667eaf520f21b3a3db0489682becc9c49bcc upstream

SETUPMAPPING is a command for use with 'virtiofsd', a fuse-over-virtio
implementation; it may find use in other fuse impelementations as well in
which the kernel does not have access to the address space of the daemon
directly.

A SETUPMAPPING operation causes a section of a file to be mapped into a
memory window visible to the kernel.  The offsets in the file and the
window are defined by the kernel performing the operation.

The daemon may reject the request, for reasons including permissions and
limited resources.

When a request perfectly overlaps a previous mapping, the previous mapping
is replaced.  When a mapping partially overlaps a previous mapping, the
previous mapping is split into one or two smaller mappings.

REMOVEMAPPING is the complement to SETUPMAPPING; it unmaps a range of
mapped files from the window visible to the kernel.

The map_alignment field communicates the alignment constraint for
FUSE_SETUPMAPPING/FUSE_REMOVEMAPPING and allows the daemon to constrain the
addresses and file offsets chosen by the kernel.
Signed-off-by: NDr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: NVivek Goyal <vgoyal@redhat.com>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: NMiklos Szeredi <mszeredi@redhat.com>
Signed-off-by: NLiu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: NJoseph Qi <joseph.qi@linux.alibaba.com>

task #28910367
commit 501ae8ecae2ba5122774dee4445003505a7fd01b upstream

virtio fs tunnels fuse over a virtio channel.  One issue is two sides might
be speaking different endian-ness. To detects this, host side looks at the
opcode value in the FUSE_INIT command.  Works fine at the moment but might
fail if a future version of fuse will use such an opcode for
initialization.  Let's reserve this opcode so we remember and don't do
this.

Same for CUSE_INIT.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMiklos Szeredi <mszeredi@redhat.com>
Signed-off-by: NLiu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: NJoseph Qi <joseph.qi@linux.alibaba.com>

task #28910367
commit 8fab010644363f8f80194322aa7a81e38c867af3 upstream

Don't hold onto dentry in lru list if need to re-lookup it anyway at next
access.  Only do this if explicitly enabled, otherwise it could result in
performance regression.

More advanced version of this patch would periodically flush out dentries
from the lru which have gone stale.
Signed-off-by: NMiklos Szeredi <mszeredi@redhat.com>
Signed-off-by: NLiu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: NJoseph Qi <joseph.qi@linux.alibaba.com>

task #28910367
commit 4388c5aac4bae5c83a2c66882043942002ba09a2 upstream

stacked file systems like virtio-fs do not have to play directly with
forget list data structures. There is a helper function use that instead.

Rename dequeue_forget() to fuse_dequeue_forget() and export it so that
stacked filesystems can use it.
Signed-off-by: NVivek Goyal <vgoyal@redhat.com>
Signed-off-by: NLiu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: NJoseph Qi <joseph.qi@linux.alibaba.com>

task #28910367
commit 79d96efffda7597b41968d5d8813b39fc2965f1b upstream

virtio-fs will need unique IDs for FORGET requests from outside
fs/fuse/dev.c.  Make the symbol visible.
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: NLiu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: NJoseph Qi <joseph.qi@linux.alibaba.com>

task #28910367
commit 0cd1eb9a4160a96e0ec9b93b2e7b489f449bf22d upstream

As of now fuse_dev_alloc() both allocates a fuse device and installs it
in fuse_conn list. fuse_dev_alloc() can fail if fuse_device allocation
fails.

virtio-fs needs to initialize multiple fuse devices (one per virtio
queue). It initializes one fuse device as part of call to
fuse_fill_super_common() and rest of the devices are allocated and
installed after that.

But, we can't affort to fail after calling fuse_fill_super_common() as
we don't have a way to undo all the actions done by fuse_fill_super_common().
So to avoid failures after the call to fuse_fill_super_common(),
pre-allocate all fuse devices early and install them into fuse connection
later.

This patch provides two separate helpers for fuse device allocation and
fuse device installation in fuse_conn.
Signed-off-by: NVivek Goyal <vgoyal@redhat.com>
Signed-off-by: NLiu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: NJoseph Qi <joseph.qi@linux.alibaba.com>

task #28910367
commit ae3aad77f46fbba56eff7141b2fc49870b60827e upstream

The /dev/fuse device uses fiq->waitq and fasync to signal that requests
are available.  These mechanisms do not apply to virtio-fs.  This patch
introduces callbacks so alternative behavior can be used.

Note that queue_interrupt() changes along these lines:

  spin_lock(&fiq->waitq.lock);
  wake_up_locked(&fiq->waitq);
+ kill_fasync(&fiq->fasync, SIGIO, POLL_IN);
  spin_unlock(&fiq->waitq.lock);
- kill_fasync(&fiq->fasync, SIGIO, POLL_IN);

Since queue_request() and queue_forget() also call kill_fasync() inside
the spinlock this should be safe.
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: NLiu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: NJoseph Qi <joseph.qi@linux.alibaba.com>

task #28910367
commit 95a84cdb11c26315a6d34664846f82c438c961a1 upstream

This will be used by virtio-fs to send init request to fuse server after
initialization of virt queues.
Signed-off-by: NVivek Goyal <vgoyal@redhat.com>
Signed-off-by: NLiu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: NJoseph Qi <joseph.qi@linux.alibaba.com>

task #28910367
commit 14d46d7abc3973a47e8eb0eb5eb87ee8d910a505 upstream

virtio-fs will need to query the length of fuse_arg lists.  Make the
symbol visible.
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: NLiu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: NJoseph Qi <joseph.qi@linux.alibaba.com>

task #28910367
commit 04ec5af0776e9baefed59891f12adbcb5fa71a23 upstream

virtio-fs will need to complete requests from outside fs/fuse/dev.c.
Make the symbol visible.
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: NLiu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: NJoseph Qi <joseph.qi@linux.alibaba.com>

task #28910367
commit 0cc2656cdb0b1f234e6d29378cb061e29d7522bc upstream

fuse_fill_super() includes code to process the fd= option and link the
struct fuse_dev to the fd's struct file.  In virtio-fs there is no file
descriptor because /dev/fuse is not used.

This patch extracts fuse_fill_super_common() so that both classic fuse
and virtio-fs can share the code to initialize a mount.

parse_fuse_opt() is also extracted so that the fuse_fill_super_common()
caller has access to the mount options.  This allows classic fuse to
handle the fd= option outside fuse_fill_super_common().
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: NLiu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: NJoseph Qi <joseph.qi@linux.alibaba.com>

task #29077503
commit 544fc7dbbf920a3e64d109c416ee229e8e1763c5 upstream
can overflow. Rather than try to catch all instances of that,
let's tweak block size to 64 bit.

It ripples through UAPI which is an ABI change, but it's not too late to
make it, and it will allow supporting >4Gbyte blocks while might
become necessary down the road.

Fixes: 5f1f79bbc9e26 ("virtio-mem: Paravirtualized memory hotplug")
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Acked-by: NDavid Hildenbrand <david@redhat.com>
Reviewed-by: NXunlei Pang <xlpang@linux.alibaba.com>

task #29077503
commit c68ab18c6aee0397574afb418f6775f23379198e upstream
Patch series "mm/memory_hotplug: handle memblocks only with
CONFIG_ARCH_KEEP_MEMBLOCK", v1.

A hotadded node/pgdat will span no pages at all, until memory is moved to
the zone/node via move_pfn_range_to_zone() -> resize_pgdat_range - e.g.,
when onlining memory blocks.  We don't have to initialize the
node_start_pfn to the memory we are adding.

This patch (of 2):

Especially, there is an inconsistency:
 - Hotplugging memory to a memory-less node with cpus: node_start_pf ==  0
 - Offlining and removing last memory from a node: node_start_pfn == 0
 - Hotplugging memory to a memory-less node without cpus: node_start_pfn != 0

As soon as memory is onlined, node_start_pfn is overwritten with the
actual start.  E.g., when adding two DIMMs but only onlining one of both,
only that DIMM (with online memory blocks) is spanned by the node.

Currently, the validity of node_start_pfn really is linked to
node_spanned_pages != 0.  With node_spanned_pages == 0 (e.g., before
onlining memory), it has no meaning.

So let's stop setting node_start_pfn, just to be overwritten via
move_pfn_range_to_zone().  This avoids confusion when looking at the code,
wondering which magic will be performed with the node_start_pfn in this
function, when hotadding a pgdat.
Signed-off-by: NDavid Hildenbrand <david@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Acked-by: NPankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Michal Hocko <mhocko@suse.com>
Link: http://lkml.kernel.org/r/20200422155353.25381-1-david@redhat.com
Link: http://lkml.kernel.org/r/20200422155353.25381-2-david@redhat.comSigned-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
(cherry picked from ccommit c68ab18c6aee0397574afb418f6775f23379198e)
Signed-off-by: NAlex Shi <alex.shi@linux.alibaba.com>
Reviewed-by: NXunlei Pang <xlpang@linux.alibaba.com>

task #29077503
commit 1c3d69ab5348b661616992206357a3ebf19b1008 upstream
statement on the first iteration through the loop.  I suspect that this
can't happen in real life, but returning a zero literal is cleaner and
silence the static checker warning.

Fixes: 5f1f79bbc9e2 ("virtio-mem: Paravirtualized memory hotplug")
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/20200610085911.GC5439@mwandaSigned-off-by: NMichael S. Tsirkin <mst@redhat.com>
(cherry picked from ccommit 1c3d69ab5348b661616992206357a3ebf19b1008)
Signed-off-by: NAlex Shi <alex.shi@linux.alibaba.com>
Reviewed-by: NXunlei Pang <xlpang@linux.alibaba.com>

task #29077503
commit b3fb6de7c6019c5d8495c3a115d42a0f118f631c upstream

Fixes: 5f1f79bbc9e2 ("virtio-mem: Paravirtualized memory hotplug")
Reported-by: Nkernel test robot <lkp@intel.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Acked-by: NDavid Hildenbrand <david@redhat.com>
(cherry picked from ccommit b3fb6de7c6019c5d8495c3a115d42a0f118f631c)
Signed-off-by: NAlex Shi <alex.shi@linux.alibaba.com>
Reviewed-by: NXunlei Pang <xlpang@linux.alibaba.com>

task #29077503
commit fce8afd76e3a4d8c59c92f84f8027569fd7031d0 upstream
The compiler will add padding after the last member, make that explicit.
The size of a request is always 24 bytes. The size of a response always
10 bytes. Add compile-time checks.

Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: teawater <teawaterz@linux.alibaba.com>
Signed-off-by: NDavid Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20200515101402.16597-1-david@redhat.comSigned-off-by: NMichael S. Tsirkin <mst@redhat.com>
(cherry picked from ccommit fce8afd76e3a4d8c59c92f84f8027569fd7031d0)
Signed-off-by: NAlex Shi <alex.shi@linux.alibaba.com>
Reviewed-by: NXunlei Pang <xlpang@linux.alibaba.com>

task #29077503
commit 72f9525ad76b1ddfe663285805982e9d57c7b2c2 upstream
Right now, we always try to unplug single subblocks when processing an
online memory block. Let's try to unplug the complete online memory block
first, in case it is fully plugged and the unplug request is large
enough. Fallback to single subblocks in case the memory block cannot get
unplugged as a whole.

Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Signed-off-by: NDavid Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20200507140139.17083-16-david@redhat.comSigned-off-by: NMichael S. Tsirkin <mst@redhat.com>
(cherry picked from ccommit 72f9525ad76b1ddfe663285805982e9d57c7b2c2)
Signed-off-by: NAlex Shi <alex.shi@linux.alibaba.com>
Reviewed-by: NXunlei Pang <xlpang@linux.alibaba.com>