uio_hv_generic: Don't free decrypted memory

In CoCo VMs it is possible for the untrusted host to cause
set_memory_encrypted() or set_memory_decrypted() to fail such that an
error is returned and the resulting memory is shared. Callers need to
take care to handle these errors to avoid returning decrypted (shared)
memory to the page allocator, which could lead to functional or security
issues.

The VMBus device UIO driver could free decrypted/shared pages if
set_memory_decrypted() fails. Check the decrypted field in the gpadl
to decide whether to free the memory.

Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
Signed-off-by: Michael Kelley <mhklinux@outlook.com>
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Link: https://lore.kernel.org/r/20240311161558.1310-5-mhklinux@outlook.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Message-ID: <20240311161558.1310-5-mhklinux@outlook.com>

Drivers: hv: Make remove callback of hyperv driver void returned

Since commit fc7a6209d571 ("bus: Make remove callback return
void") forces bus_type::remove be void-returned, it doesn't
make much sense for any bus based driver implementing remove
callbalk to return non-void to its caller.

As such, change the remove function for Hyper-V VMBus based
drivers to return void.

Signed-off-by: Dawei Li <set_pte_at@outlook.com>
Link: https://lore.kernel.org/r/TYCP286MB2323A93C55526E4DF239D3ACCAFA9@TYCP286MB2323.JPNP286.PROD.OUTLOOK.COM
Signed-off-by: Wei Liu <wei.liu@kernel.org>

Drivers: hv: vmbus: Mark vmbus ring buffer visible to host in Isolation VM

Mark vmbus ring buffer visible with set_memory_decrypted() when
establish gpadl handle.

Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Signed-off-by: Tianyu Lan <Tianyu.Lan@microsoft.com>
Link: https://lore.kernel.org/r/20211025122116.264793-5-ltykernel@gmail.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>

uio_hv_generic: Fix another memory leak in error handling paths

Memory allocated by 'vmbus_alloc_ring()' at the beginning of the probe
function is never freed in the error handling path.

Add the missing 'vmbus_free_ring()' call.

Note that it is already freed in the .remove function.

Fixes: cdfa835c6e5e ("uio_hv_generic: defer opening vmbus until first use")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/0d86027b8eeed8e6360bc3d52bcdb328ff9bdca1.1620544055.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

uio_hv_generic: Fix a memory leak in error handling paths

If 'vmbus_establish_gpadl()' fails, the (recv|send)_gpadl will not be
updated and 'hv_uio_cleanup()' in the error handling path will not be
able to free the corresponding buffer.

In such a case, we need to free the buffer explicitly.

Fixes: cdfa835c6e5e ("uio_hv_generic: defer opening vmbus until first use")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/4fdaff557deef6f0475d02ba7922ddbaa1ab08a6.1620544055.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

uio: uio_hv_generic: use devm_kzalloc() for private data alloc

This is a minor cleanup for the management of the private object of this
driver. The allocation can be tied to the life-time of the hv_device
object.
This cleans up a bit the exit & error paths, since the object doesn't need
to be explicitly free'd anymore.

Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Link: https://lore.kernel.org/r/20201119154903.82099-4-alexandru.ardelean@analog.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

uio_hv_generic: add missed sysfs_remove_bin_file

This driver calls sysfs_create_bin_file() in probe, but forgets to
call sysfs_remove_bin_file() in remove.
Add the missed call to fix it.

Signed-off-by: Chuhong Yuan <hslester96@gmail.com>
Link: https://lore.kernel.org/r/20200507151343.792816-1-hslester96@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

uio_hv_generic: set callbacks on open

This fixes the problem where uio application was unable to
use multple queues on restart. The root cause is that the callbacks
are cleared on disconnect. Change to setting up callbacks
everytime in open.

Fixes: cdfa835c6e5e ("uio_hv_generic: defer opening vmbus until first use")
Reported-by: Mohammed Gamal <mgamal@redhat.com>
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

uio_hv_generic: defer opening vmbus until first use

This fixes two design flaws in hv_uio_generic.

Since hv_uio_probe is called from vmbus_probe with lock held
it potentially can cause sleep in an atomic section because
vmbus_open will wait for response from host.

The hv_uio_generic driver could not handle applications
exiting and restarting because the vmbus channel was
persistent. Change the semantics so that the buffers are
allocated on probe, but not attached to host until
device is opened.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

hv_uio_generic: map ringbuffer phys addr

The ring buffer is contiguous IOVA and is mapped via phys addr
for sysfs file. Use same method for the UIO mapping.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

vmbus: keep pointer to ring buffer page

Avoid going from struct page to virt address (and back) by just
keeping pointer to the allocated pages instead of virt address.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

uio_hv_generic: drop #ifdef DEBUG

DEBUG is leftover from the development phase, remove it.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

uio_hv_generic: increase size of receive and send buffers

When using DPDK there is significant performance boost by using
the largest possible send and receive buffer area.

Unfortunately, with UIO model there is not a good way to configure
this at run time. But it is okay to have a bigger buffer available
even if application only decides to use a smaller piece of it.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

uio: add SPDX license tags

For those without any license text present or short reference
to GPL, add SPDX tag.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

uio_hv_generic: fix subchannel ring mmap

The fault method of handling subchannel ring, did not work correctly
(it only worked for the first page).

Since ring buffer is physically contiguous, using the vm helper
function is simpler and handles more cases.

Fixes: 37b96a4931db ("uio_hv_generic: support sub-channels")
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

uio_hv_generic: use correct channel in isr

Need to mask the correct sub-channel in the callback from VMBUS
isr. Otherwise, can get in to infinite interrupt storm.

Fixes: 37b96a4931db ("uio_hv_generic: support sub-channels")
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

uio_hv_generic: make ring buffer attribute for primary channel

The primary channel also needs a ring buffer attribute. This allows
application to check if kernel supports uio sub channels, and also
makes all channels use consistent API.

Fixes: 37b96a4931db ("uio_hv_generic: support sub-channels")
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

uio_hv_generic: set size of ring buffer attribute

The original code had ring size as a module parameter, but
then it was made a fixed value. The code to set the size of
the ring buffer binary file was lost in the transistion.
The size is needed by user mode driver to know the size of
the ring buffer.

Fixes: 37b96a4931db ("uio_hv_generic: support sub-channels")
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

uio_hv_generic: support sub-channels

Use sysfs to allow supporting sub-channels. The userspace application
makes request to host to create sub-channels and the UIO kernel
driver populates the sysfs per-channel directory with a binary
attribute file that can be used to read/write ring.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

uio_hv_generic: fix new type mismatch warnings

In commit 72d146578950 ("uio_hv_generic: fix type mismatch warnings"),
I addressed some warnings that show up with CONFIG_X86_PAE, now a new
change has added more of the same:

drivers/uio/uio_hv_generic.c: In function 'hv_uio_probe':
drivers/uio/uio_hv_generic.c:205:5: error: cast from pointer to integer of different size [-Werror=pointer-to-int-cast]
drivers/uio/uio_hv_generic.c:225:5: error: cast from pointer to integer of different size [-Werror=pointer-to-int-cast]

The fix is the same as before, casting to uintptr_t as an intermediate.

Fixes: e7d214642a19 ("uio_hv_generic: create send and receive buffers")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

uio_hv_generic: fix type mismatch warnings

I moved the virt_to_phys() conversion into hv_uio_probe() as part of
a warning fix. Stephen's cleanup to remove the private mmap() function
seems reasonable, but part of it reverted the change that I did to
hide the warnings, so they are back now:

drivers/uio/uio_hv_generic.c: In function 'hv_uio_probe':
drivers/uio/uio_hv_generic.c:123:5: error: cast from pointer to integer of different size [-Werror=pointer-to-int-cast]
drivers/uio/uio_hv_generic.c:130:5: error: cast from pointer to integer of different size [-Werror=pointer-to-int-cast]
drivers/uio/uio_hv_generic.c:136:5: error: cast from pointer to integer of different size [-Werror=pointer-to-int-cast]

The type mismatch is now the result of the uio_mmap() definition, and
the best way I see from here is to shut them up with a uintptr_t cast.

Fixes: 9c40546c012c ("uio_hv_generic: use standard mmap for resources")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

uio_hv_generic: add rescind support

When host rescinds the device, the UIO driver will clear the interrupt
state and notify application. The read (or write) on the interrupt FD
will then fail with -EIO. This is simpler than adding lots extra uevent
stuff inside UIO.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

uio_hv_generic: check that host supports monitor page

In order for userspace application to signal host, it needs the
host to support the monitor page property. Check for the flag
and fail if this is not supported.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

uio_hv_generic: create send and receive buffers

Map in receive and send buffers for networking in UIO device.
These buffers are special and need to be setup by kernel
API's; userspace can not do it.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

uio_hv_generic: use ISR callback method

The UIO IRQ handler doesn't need to be called from a tasklet.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

uio_hv_generic: use standard mmap for resources

The generic UIO mmap should work for us.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

uio_hv_generic: fix configuration comments

The suggested method for configuration does not work with
current kernels. Paths and ids changed.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

vmbus: add direct isr callback mode

Change the simple boolean batched_reading into a tri-value.
For future NAPI support in netvsc driver, the callback needs to
occur directly in interrupt handler.

Batched mode is also changed to disable host interrupts immediately
in interrupt routine (to avoid unnecessary host signals), and the
tasklet is rescheduled if more data is detected.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

uio-hv-generic: store physical addresses instead of virtual

gcc warns about the newly added driver when phys_addr_t is wider than
a pointer:

drivers/uio/uio_hv_generic.c: In function 'hv_uio_mmap':
drivers/uio/uio_hv_generic.c:71:17: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast]
virt_to_phys((void *)info->mem[mi].addr) >> PAGE_SHIFT,
drivers/uio/uio_hv_generic.c: In function 'hv_uio_probe':
drivers/uio/uio_hv_generic.c:140:5: error: cast from pointer to integer of different size [-Werror=pointer-to-int-cast]
= (phys_addr_t)dev->channel->ringbuffer_pages;
drivers/uio/uio_hv_generic.c:147:3: error: cast from pointer to integer of different size [-Werror=pointer-to-int-cast]
(phys_addr_t)vmbus_connection.int_page;
drivers/uio/uio_hv_generic.c:153:3: error: cast from pointer to integer of different size [-Werror=pointer-to-int-cast]
(phys_addr_t)vmbus_connection.monitor_pages[1];

I can't see why we store a virtual address in a phys_addr_t here,
as the only user of that variable converts it into a physical
address anyway, so this moves the conversion to where it logically
fits according to the types.

Fixes: 95096f2fbd10 ("uio-hv-generic: new userspace i/o driver for VMBus")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

uio-hv-generic: new userspace i/o driver for VMBus

This is a new driver to enable userspace networking on VMBus.
It is based largely on the similar driver that already exists
for PCI, and earlier work done by Brocade to support DPDK.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>