misc: mei: client.c: fix problem of return '-EOVERFLOW' in mei_cl_write

Clang static analyzer complains that value stored to 'rets' is never
read.Let 'buf_len = -EOVERFLOW' to make sure we can return '-EOVERFLOW'.

Fixes: 8c8d964ce90f ("mei: move hbuf_depth from the mei device to the hw modules")
Signed-off-by: Su Hui <suhui@nfschina.com>
Link: https://lore.kernel.org/r/20231120095523.178385-2-suhui@nfschina.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

misc: mei: client.c: return negative error code in mei_cl_write

mei_msg_hdr_init() return negative error code, rets should be
'PTR_ERR(mei_hdr)' rather than '-PTR_ERR(mei_hdr)'.

Fixes: 0cd7c01a60f8 ("mei: add support for mei extended header.")
Signed-off-by: Su Hui <suhui@nfschina.com>
Link: https://lore.kernel.org/r/20231120095523.178385-1-suhui@nfschina.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

misc: mei: client.c: fix kernel-doc warnings

Fix kernel-doc warnings in client.c:

client.c:53: warning: contents before sections
client.c:68: warning: contents before sections
client.c:334: warning: contents before sections
client.c:349: warning: contents before sections
client.c:364: warning: contents before sections

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Tomas Winkler <tomas.winkler@intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20231012024845.29169-3-rdunlap@infradead.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: clean pending read with vtag on bus

Client on bus have only one vtag map slot and should disregard the vtag
value when cleaning pending read flag.
Fixes read flow control message unexpectedly generated when
clent on bus send messages with different vtags.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Reviewed-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Alan Previn <alan.previn.teres.alexis@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230125082637.118970-4-alan.previn.teres.alexis@intel.com

mei: add timeout to send

When driver wakes up the firmware from the low power state,
it is sending a memory ready message.
The send is done via synchronous/blocking function to ensure
that firmware is in ready state. However, in case of firmware
undergoing reset send might be block forever.
To address this issue a timeout is added to blocking
write command on the internal bus.

Introduce the __mei_cl_send_timeout function to use instead of
__mei_cl_send in cases where timeout is required.
The mei_cl_write has only two callers and there is no need to split
it into two functions.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Link: https://lore.kernel.org/r/20221116124735.2493847-2-alexander.usyskin@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: add support to GSC extended header

GSC extend header is of variable size and data
is provided in a sgl list inside the header
and not in the data buffers, need to enable the path.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Vitaly Lubart <vitaly.lubart@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20220928004145.745803-2-daniele.ceraolospurio@intel.com

mei: extend timeouts on slow devices

Parametrize operational timeouts in order
to support slow firmware on some graphics devices.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Reviewed-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220907215113.1596567-9-tomas.winkler@intel.com
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>

mei: me: avoid link reset on shutdown

Avoid lingering reset thread on driver shutdown.
If the firmware is down during a shutdown flow
do not initiate the link reset, simply disconnect
all clients and let shutdown flow finish

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Link: https://lore.kernel.org/r/20220215080438.264876-2-tomas.winkler@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: cleanup status before client dma setup call

The upper layer may retry call to mei_cl_dma_alloc_and_map(),
in that case the client status may be non-zero after the previous call
and the wait condition will be true immediately.
Set cl->status to zero to allow waiting for an actual result
from the firmware.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Link: https://lore.kernel.org/r/20211223094705.204624-2-tomas.winkler@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: bus: add client dma interface

Expose the client dma mapping via mei client bus interface.
The client dma has to be mapped before the device is enabled,
therefore we need to create device linking already during mapping
and we need to unmap after the client is disable hence we need to
postpone the unlink and flush till unmapping or when
destroying the device.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Co-developed-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20210420172755.12178-1-emmanuel.grumbach@intel.com
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20211112062814.7502-1-emmanuel.grumbach@intel.com

mei: revamp mei extension header structure layout.

The mei extension header was build as array of flexible structures
which will not work if actually more headers are added.
(Currently only vtag header was used).
Sparse reports:

drivers/misc/mei/hw.h:253:32: warning: array of flexible structures

Use basic type u8 for the variable sized extension.
Define explicitly mei_ext_hdr_vtag structure.
And also fix mei_ext_next() function to point correctly to the
end of the header.

Note: the headers are part of firmware interface and need to be __packed.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Link: https://lore.kernel.org/r/20210621193756.134027-2-tomas.winkler@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: fix kdoc in the driver

Over time the functions were renamed,
but this was not always reflected in kdoc, fix that.

Signed-off-by: Tamar Mashiah <tamar.mashiah@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Link: https://lore.kernel.org/r/20210621193756.134027-1-tomas.winkler@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: allow map and unmap of client dma buffer only for disconnected client

Allow map and unmap of the client dma buffer only when the client is not
connected. The functions return -EPROTO if the client is already connected.
This is to fix the race when traffic may start or stop when buffer
is not available.

Cc: <stable@vger.kernel.org> #v5.11+
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Link: https://lore.kernel.org/r/20210318055959.305627-1-tomas.winkler@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: implement client dma setup.

Implement HBM message protocol to setup and tear down
DMA buffer on behalf of an client. On top there DMA
buffer allocation and its life time management.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Link: https://lore.kernel.org/r/20210206144325.25682-5-tomas.winkler@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: allow clients on bus to communicate in remove callback

Introduce new intermediate state to allow the clients on the bus
to communicate with the firmware from the remove handler.
This is to enable to perform a clean shutdown.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Link: https://lore.kernel.org/r/20210206144325.25682-2-tomas.winkler@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: document that mei_msg_hdr_init returns ERR_PTR

Document that mei_msg_hdr_init returns ERR_PTR.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Link: https://lore.kernel.org/r/20210129120752.850325-2-tomas.winkler@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: bus: add vtag support

Add API to support vtag in communication on mei bus.

Add mei_cldev_send_vtag, mei_cldev_recv_vtag and
mei_cldev_recv_nonblock_vtag functions to allow sending a message
with vtag set and to receive vtag of an incoming message.

Cc: Sean Z Huang <sean.z.huang@intel.com>
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Link: https://lore.kernel.org/r/20201116125612.1660971-1-tomas.winkler@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: handle tx queue flushing for vtag connections

Since multiple file pointers (fp) can be associated
with a single host client, upon close() only objects
associated with the fp has to flushed from the tx queues.
The control queues should be flushed only when all
the connections are closed and the client is disconnected.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Link: https://lore.kernel.org/r/20200818115147.2567012-9-tomas.winkler@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: add a vtag map for each client

Vtag map is a list of tuples of vtag and file pointer (struct
mei_cl_vtag) associated with a particular me host client.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Link: https://lore.kernel.org/r/20200818115147.2567012-8-tomas.winkler@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: add a spin lock to protect rd_completed queue

In order to support vtags we need to access read completed
queue out of driver big lock.
Add a spin lock to protect rd_completed queue.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Link: https://lore.kernel.org/r/20200818115147.2567012-7-tomas.winkler@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: add support for mei extended header.

Add an extend header beyond existing 4 bytes of the mei message header.
The extension is of variable length, starting with meta header
that contains the number of headers and the overall size of
the extended headers excluding meta header itself followed by
TLV list of extended headers. Currently only supported extension is
the vtag. From the HW perspective the extended headers is already
part of the payload.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Link: https://lore.kernel.org/r/20200818115147.2567012-5-tomas.winkler@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: client: use sizeof of variable instead of struct type

There is a possibility of bug when variable type has changed but
corresponding struct passed to the sizeof has not.

Cc: Gustavo A. R. Silva <gustavoars@kernel.org>
Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Link: https://lore.kernel.org/r/20200723145927.882743-5-tomas.winkler@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: release me_cl object reference

Allow me_cl object to be freed by releasing the reference
that was acquired by one of the search functions:
__mei_me_cl_by_uuid_id() or __mei_me_cl_by_uuid()

Cc: <stable@vger.kernel.org>
Reported-by: 亿一 <teroincn@gmail.com>
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Link: https://lore.kernel.org/r/20200512223140.32186-1-tomas.winkler@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: limit number of bytes in mei header.

The MEI message header provides only 9 bits for storing
the message size, limiting to 511.
In theory the host buffer (hbuf) can contain up to 1020 bytes
(limited by byte = 255 * 4)
With the current hardware and hbuf size 512, this is not a real issue,
but as hardening approach we enforce the limit.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Link: https://lore.kernel.org/r/20200211160522.7562-1-tomas.winkler@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: expose device state in sysfs

Expose mei device state to user-space through sysfs.
This gives indication to applications that driver is in transition,
usefully mostly to detect link reset state.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: adjust the copyright notice in the files.

Use unified version of the copyright notice in the files
Update copyright years according the year the files
were touched, except this patch and SPDX conversions.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: convert to SPDX license tags

Replace boiler plate licenses texts with the SPDX license
identifiers in the mei files header.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: free read cb on ctrl_wr list flush

There is a little window during disconnection flow
when read cb is moved between lists and may be not freed.
Remove moving read cbs explicitly during flash fixes this memory
leak.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: dma ring: implement transmit flow

Implement a circular buffer on allocated system memory. Read and write
indices are stored on the control block which is also shared between the
device and the host.
Two new functions are exported from the DMA module: mei_dma_ring_write,
and mei_dma_ring_empty_slots. The former simply copy a packet on the TX
DMA circular buffer and later, returns the number of empty slots on the
TX DMA circular buffer.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: dma ring: implement rx circular buffer logic

Implement circular buffer protocol over receive dma
buffer. Add extension to the mei message header that holds
length of the buffer on the dma buffer.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: expedite ioctl return on the notify set operation error

The notify set operation ioctl will wait till timeout is expired
even in case when the FW returned an error.
Check the status field of the client object in wait_event_timeout()
to determine if the caller can return earlier.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: flush queues by the host client only

During queues flush, the me client in most cases is already
unlinked hence the me client id is unavailable. The host client
structure pointer is enough for identification.
The function mei_cl_cmp_id() is dropped as it has no more usage.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: fix use-after-free in mei_cl_write

KASAN reports a use-after-free during startup, in mei_cl_write:

BUG: KASAN: use-after-free in mei_cl_write+0x601/0x870 [mei]
(drivers/misc/mei/client.c:1770)

This is caused by commit 98e70866aacb ("mei: add support for variable
length mei headers."), which changed the return value from len, to
buf->size. That ends up using a stale buf pointer, because blocking
call, the cb (callback) is deleted in me_cl_complete() function.

However, fortunately, len remains unchanged throughout the function
(and I don't see anything else that would require re-reading buf->size
either), so the fix is to simply revert the change, and return len, as
before.

Fixes: 98e70866aacb ("mei: add support for variable length mei headers.")
CC: Arnd Bergmann <arnd@arndb.de>
CC: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: hbm: introduce dma bit in the message header

Add dma_ring bit in the mei message header for conveying
that the message data itself are on the dma ring.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: add support for variable length mei headers.

Remove header size knowledge from me and txe hw layers,
this requires to change the write handler to accept
header and its length as well as data and its length.

HBM messages are fixed to use basic header, hence we add mei_hbm2slots()
that converts HBM message length and mei message header,
while mei_data2slots() converts data length directly to the slots.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: add mei_msg_hdr_init wrapper.

Wrap the mei header boilerplate initialization code in
mei_msg_hdr_init function. On the way remove 'completed'
field from mei_cl_cb structure as this information
is already included in the header and is local to particular
fragment.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: move hbuf_depth from the mei device to the hw modules

The host buffer depth is hardware specific so it's better to
handle it inside the me and txe hw modules. In me the depth
is read from register in txe it's a constant number.
The value is now retrieved via mei_hbuf_depth accessor,
while it replaces mei_hbuf_max_len.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: cleanup slots to data conversions

Cleanup conversions between slots and data.
Define MEI_SLOT_SIZE instead of using 4 or sizeof(u32) across
the source code.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: fix ssize_t to int assignment in read and write ops.

Use ssize_t for rets variables in mei_write(), mei_read(), and
mei_cl_write() as well as change the return type of mei_cl_write()
to ssize_t, to prevent assignment of possible 64bit size_t
to int 32 bit variable.

As by product also eliminate warning
drivers/misc/mei/client.c:1702:11: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: check for error returned from mei_hbuf_empty_slots()

mei_hbuf_empty_slots() may return with an error in case
of circular buffer overflow. This type of error may
be caused only by a bug. However currently, the error
won't be detected due signed type promotion in comparison to u32.
We add explicit check for less then zero and explicit cast
in comparison to suppress singn-compare warning.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: limit the number of queued writes

Limit the number of queued writes per client.
Writes above this threshold are blocked till place
in the transmit queue is available.
The limit is configurable via sysfs and defaults to 50.
The implementation should provide blocking I/O behavior.
Prior to this change one would end up in the hands of OOM.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: make module referencing local to the bus.c

Module reference counting is relevant only to the
mei client devices. Make the implementation clean
and move it to bus.c

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: set device client to the disconnected state upon suspend.

This fixes regression introduced by
commit 8d52af6795c0 ("mei: speed up the power down flow")

In mei_cldev_disable during device power down flow, such as
suspend or system power off, it jumps over disconnecting function
to speed up the power down process, however, because the client is
unlinked from the file_list (mei_cl_unlink) mei_cl_set_disconnected
is not called from mei_cl_all_disconnect leaving resource leaking.
The most visible is reference counter on underlying HW module is
not decreased preventing to remove modules after suspend/resume cycles.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Fixes: 8d52af6795c0 ("mei: speed up the power down flow")
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: drop amthif internal client

AMTHIF has special support in the mei drive, it handles multiplexing
multiple user space connection above single me client connection.
Since there is no additional addressing information there is a strict
requirement on the traffic order on each connection and on the "read
after write" order within the connection. This creates a lot of
complexity mostly because the other client types do not necessarily fall
under the same restriction. After carefully studying the use of the
AMTHIF client, we came to conclusion that the multiplexing is not really
utilized by any application and we may safely remove that support and
significantly simplify the driver.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

sched/headers: Prepare to move signal wakeup & sigpending methods from <linux/sched.h> into <linux/sched/signal.h>

Fix up affected files that include this signal functionality via sched.h.

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

mei: revamp io list cleanup function.

Specify in function names by which object is the io list filtered:
cl for a client and fp for file descriptor.
In that course a code duplication is resolved by dropping
mei_cl_read_cb_flush and mei_clear_list and using
mei_io_list_free_fp function.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: replace callback structures used as list head by list_head

mei_dev structure used struct mei_cl_cb type variables as for holding
callbacks list heads. Replace them by the actual struct list_head
as there is no other info that is handled. This slims down
the mei_dev structure and mostly streamline the code.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: amthif: clean command queue upon disconnection

In order to prevent memory leak clean up the amthif command
queue upon disconnection. The issue may happen only on error path
as the command queue is cleaned upon file descriptor close.
And remove the cleanup from mei_cl_flush_queues as this code
is never reached for amthif client.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: abort waiting for notification on unsupported HW

On legacy HW, pre Skylake, the notifications are not supported,
return -EOPNOTSUPP in mei_cl_notify_get and prevent
waiting indefinitely.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: return error on notification request to a disconnected client

Request for a notification from a disconnected client will be ignored
silently by the FW but the caller should know that the operation hasn't
succeeded.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: bus: prevent hardware module unload if device on bus is active

The hardware module should not be unloaded if the bus
has active devices.
Get get_/put_ bus parent module upon client device
connection/disconnection, to prevent the hardware managing
module to disappear underneath.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: make mei_cl_set_disconnected static

mei_cl_set_disconnected is used only in client.c,
so make it local to the file and mark static.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: make mei_io_list_flush static

mei_io_list_flush is used only in client.c
so make it local to the file and mark static.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: move write cb to completion on credentials failures

The credentials handling was pushed to the write handlers
but error handling wasn't done properly.
Move write callbacks to completion queue to destroy them
and to notify a blocked writer about the failure

Fixes: 136698e535cd1 (mei: push credentials inside the irq write handler)
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: request async autosuspend at the end of enumeration

pm_runtime_autosuspend can take synchronous or asynchronous
paths, Because we are calling pm_runtime_mark_last_busy just before
this most of the cases it takes the asynchronous way. However,
when the FW or driver resets during already running runtime suspend,
the call will result in calling to the driver's rpm callback and results
in a deadlock on device_lock.
The simplest fix is to replace pm_runtime_autosuspend with
asynchronous pm_request_autosuspend.

Cc: <stable@vger.kernel.org> # 4.4+
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: bus: split RX and async notification callbacks

Split callbacks for RX and async notification events on mei bus to
eliminate synchronization problems and to open way for RX optimizations.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: introduce host client uninitialized state

Introduce a new host client state, MEI_FILE_UNINITIALIZED,
to distinguish client objects that was unlinked,
but not destroyed and can be linked again.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: fix parameter rename KDoc

Parameter renaming to fop_type was not reflected in KDoc

Fixes: 3030dc0564594 (mei: add wrapper for queuing control commands)
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: enable to set the internal flag for client write

Prepare the client write functions to set the internal flag in message
header. Carry both blocking and internal modes inside the transmit cb,
and call internal bus function __mei_cl_send() with send mode bit mask.
The Internal flag should be added only on messages generated by the
driver.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: stop the stall timer worker if not needed

The stall timer worker checks periodically if there is a stalled i/o
transaction. The issue with the current implementation is that the timer
is ticking also when there is no pending i/o transaction.
This patch provides a simple change that prevents rescheduling
of the delayed work when there is no pending i/o.

Cc: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: amthif: drop mei_amthif_read

mei_amthif_read have only one difference from mei_read, it is not
calling mei_read_start().
Make mei_read_start return immediately for amthif client and drop the
special mei_amthif_read function.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: add wrapper for queuing control commands.

Enclose the boiler plate code of allocating a control/hbm command cb
and enqueueing it onto ctrl_wr.list in a convenient wrapper
mei_cl_enqueue_ctrl_wr_cb().

This is a preparatory patch for enabling consecutive reads.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: use consistent naming for TX control flow credits

With the introduction of the receive control flow credits prefixed with
rx_ we add tx_ prefix to the variables and function used for tracking
the transmit control flow credits.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: rx flow control counter

Use RX flow control counter in the host client structure to
track the number of simultaneous outstanding reads.
This eliminates search in queues and makes ground for
enabling for parallel read.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: prepare read cb for fixed address clients on the receive path only.

The read callbacks for the fixed address clients, that don't have flow
control are built now on the receive path. In order to have a single
allocation place we remove the allocation from the read request.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: add read callback on demand for fixed_address clients

The Fixed address clients do not work with the flow control, and the
packet RX callback was allocated upon TX with anticipation of a
following RX. This won't work if the clients with unsolicited Rx. Rather
than preparing read callback upon a write we allocate one directly on
the reciev path if one doesn't exists.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: drop mei_io_cb_alloc_buf

mei_io_cb_alloc_buf have a single caller :mei_cl_alloc_cb. After amthif
stopped using it, the code can be integrated into the caller and the
function can be dropped.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: don't use wake_up_interruptible for wr_ctrl

wr_ctrl waiters are none interruptible, so should be waken up
with call to wake_up and not to wake_up_interruptible.

This fixes commit:
7ff4bdd ("mei: fix waiting for wr_ctrl for corner cases.")

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: fix waiting for wr_ctrl for corner cases.

A control message reply may not be received if either a link reset has
occurred or disconnection is initiated by the FW.
In the both cases the client state will be set straight to DISCONNECTED
and the driver will wait till timeout.
Adding DISCONNECTED state in the waiting condition will release the
client from the stall.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: don't clean control queues on notify request timeout

Timeout on notify request is not a fatal condition, and actually
cleaning control queues will disrupt other control flows of the
same client.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: fix NULL dereferencing during FW initiated disconnection

In the case when disconnection is initiated from the FW
the driver is flushing items from the write control list while
iterating over it:

mei_irq_write_handler()
list_for_each_entry_safe(ctrl_wr_list) <-- outer loop
mei_cl_irq_disconnect_rsp()
mei_cl_set_disconnected()
mei_io_list_flush(ctrl_wr_list) <-- destorying list

We move the list flushing to the completion routine.

Cc: <stable@vger.kernel.org> #4.2+
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: fix format string in debug prints

buf_idx type was changed to size_t, and few places
missed out to change the print format from %ld to %zu.
Use also uz for buf.size which is also of size_t

Fixes:
commit 56988f22e097 ("mei: fix possible integer overflow issue")'

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: fix double freeing of a cb during link reset

Fix double freeing of the cb that can happen if link reset kicks in the
middle of blocked write from a device on the cl bus.

Free cb inside mei_cl_write function on failure and drop cb free
operation from callers, during a link reset the mei_cl_write function
returns with an error, but the caller doesn't know if the cb was
already queued or not so it doesn't know if the cb will be freed upon
queue reclaim or it has to free it itself.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: split amthif client init from end of clients enumeration

The amthif FW client can appear after the end of client enumeration.
Amthif host client initialization is done now at FW client discovery
time.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: drop reserved host client ids

The reserved host clients can be obsoleted now, a portion of the
platforms is shipped without iAMT enabled, where the reservation is not
relevant and for platforms with iAMT dynamic allocation is sufficient.
Dropping reserved ids makes enumeration more flexible and generic

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: fill file pointer in read cb for fixed address client

The read callback created from a flow control request for
a fixed address client have NULL in the file pointer.
Fill the file pointer using a data from a write callback.

This allows us to drop workaround introduced in:
commit eeabfcf5a92a ("mei: connection to fixed address clients from user-space")

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: clean write queues and wake waiters on disconnect

Clean write and write_waiting queues in disconnect.
Requests in those queues are stale and processing will lead to
fat warnings.

In multi thread operations on disconnect and in FW disconnect case -
write/read/event waiters should end wait and return error.
Wake all waiters for disconnecting client to achieve that.

Drop wake all and write queue clean on reset,
as now we waking all waiters and cleaning write queues on disconnect.
No need to do it twice.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: wake blocked write on link reset

In case of link reset all blocked writes should be interrupted.
Note, that currently blocking write is used only through bus layer.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: bus: fix notification event delivery

Call wake_up cl->ev_wait only in case there is no bus client registered
to the event notification.
Second, since we don't have exclusive waiter wake_up_interruptible_all
is not used correctly here.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: bus: fix RX event scheduling

In this particular case this more correct and safer to check if the RX
event is set in the event mask rather than query waitqueue_active
Since the check is already performed in the mei_cl_bus_rx_event
function, it is just required to check for its return value.
Second, since we don't have exclusive waiter wake_up_interruptible_all
is not used correctly here.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: amthif: replace amthif_rd_complete_list with rd_completed

Now when we have per client rd_completed list we can remove
the amthif specific amthif_rd_complete_list.
In addition in the function mei_amthif_read do not loop over the
rd_completed list like the original code as the code path is unlocked.

Reviewed-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: rename variable names 'file_object' to fp

The driver uses three names file, fp, and file_object for
struct file type. To improve code clarity and adjust to my taste
rename file_object to more common and shorter fp.

Reviewed-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: constify struct file pointer

The struct file file pointer is used as an opaque handle to for a
connected client, for this part the pointer should be immutable and
should be set to count.

Reviewed-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: fix possible integer overflow issue

There is a possible integer overflow following by a buffer overflow
when accumulating messages coming from the FW to compose a full payload.
Occurrence of wrap around has to be prevented for next message size
calculation.
For unsigned integer the addition overflow has occurred when the
result is smaller than one of the arguments.
To simplify the fix, the types of buf.size and buf_idx are set to the
same width, namely size_t also to be aligned with the type of length
parameter in file read/write ops.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: wd: drop the watchdog code from the core mei driver

Instead of integrating the iAMT watchdog in the mei core driver
we will create a watchdog device on the mei client bus and
create a driver for it.

This patch removes the watchdog code from the mei core driver.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: prevent queuing new flow control credit.

The MEI FW can receive only one flow control for read.
Currently the driver only checks if a flow control credit was already
sent and read is pending in the rd_pending queue, but it also has to
check if flow control credit already queued in the write control queue
to prevent sending more than one flow control credits.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: remove check on pm_runtime_active in __mei_cl_disconnect

Remove bogus check on pm_runtime_active that prevented
disconnection from a client in case the device was resuming
from power gating but not yet active.

Fix regression introduced by
18901357e70ae29e3fd1c58712a6847c2ae52eae
mei: disconnect on connection request timeout

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: bus: add and call callback on notify event

Enable drivers on mei client bus to subscribe
to asynchronous event notifications.
Introduce events_mask to the existing callback infrastructure
so it is possible to handle both RX and event notification.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: implement fasync for event notification

A process can be informed about client notification also via
SIGIO with POLL_PRI event.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: add a handler that waits for notification on event

mei_cl_notify_get is to be called by a host client
to wait, receive, and ack the event notification.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: add mei_cl_notify_request command

Add per client notification request infrastructure
that allows client to enable or disable async
event notification.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: disconnect on connection request timeout

For the FW with HBM version >= 2.0 we don't need to reset the whole
device in case of a particular client failing to connect, it is enough
to send disconnect a request to bring the device to the stable state.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: bus: link client devices instead of host clients

MEI bus was designed around nfc and was hard to extend.
Instead of the hard coded way of adding the devices on the mei bus
we scan the whole me client list and create a device for each
eligible me client (mei_cl_bus_rescan); currently we support
only clients with single connection and fixed address clients.
NFC radio name detection is run as a fixup routine

The patch replaces handling the device list based on struct me_cl
to device list based on me_cl_devices. The creating a connection
is pushed from the device creation time to device enablement.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: do not access freed cb in blocking write

The mei_cl_write function is giving up on a write cb ownership after it
was sent or queued. The write cb is then freed in the completion
handler. Especially during blocking write mei_cl_write function waits
for the completion handler and then access the freed memory to fetch the
written size. The quick fix is to store the buffer size prior to
sending, the size is not altered during the flow.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: me: wait for power gating exit confirmation

Fix the hbm power gating state machine so it will wait till it receives
confirmation interrupt for the PG_ISOLATION_EXIT message.

In process of the suspend flow the devices first have to exit from the
power gating state (runtime pm resume).
If we do not handle the confirmation interrupt after sending
PG_ISOLATION_EXIT message, we may receive it already after the suspend
flow has changed the device state and interrupt will be interpreted as a
spurious event, consequently link reset will be invoked which will
prevent the device from completing the suspend flow

kernel: [6603] mei_reset:136: mei_me 0000:00:16.0: powering down: end of reset
kernel: [476] mei_me_irq_thread_handler:643: mei_me 0000:00:16.0: function called after ISR to handle the interrupt processing.
kernel: mei_me 0000:00:16.0: FW not ready: resetting

Cc: <stable@vger.kernel.org> #3.18+
Cc: Gabriele Mazzotta <gabriele.mzt@gmail.com>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=86241
Link: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=770397
Tested-by: Gabriele Mazzotta <gabriele.mzt@gmail.com>
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: reset flow control on the last client disconnection

The FW resets the flow control for single buffer clients when the last
host client disconnects, also the driver has to follow this policy and
zero the flow control counter in such case.

Cc: <stable@vger.kernel.org> #4.1
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: request autosuspend at the end of write

On longer non-blocking write might not complete at the end of
autosuspend expiration, therefore we request autosuspend
again on the write completion.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: consume flow control on the first chunk of writing

Consume the write flow control on the first chunk of the write instead
of on the buffer completion.
We can safely assume that the consequent chunks have the flow control
granted.

This addresses two issues:

1. Blocks other callbacks from the same client riding on the client's
flow control and prevents interleaving of messages as FW cannot distinguish
between two messages from the same client.

2. Fixes single buffer flow control arbitration in a clean way, without
connection/disconnection book keeping

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: support for fixed address clients

Fixed address is simplified FW client that doesn't require
connection and doesn't support flow control.
So it can be only one host client per fixed FW client.
Fixed client access is available only for drivers on mei bus,
connection from user-space is blocked.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: fix flow control for single buffer clients

For ME clients that use single receiving buffer
the driver tracks credentials on mei_me_clients structure
for all connections. The driver needs to book keep the shared
resource correctly and track the connections, particularly
the credit has to be cleaned when there is no active connection
to a particular me client. This solves issue when subsequent
connection will not get an ill impression that it can write.

We add active connection counter the particular ME client and
when the counter reach zero, we clear the credits.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: add a reference from the host client to the me client

Keep a pointer to associated me client in the host client object to
eliminate me client searches. Check if the me client is active in the
firmware by checking if its is linked on the me clients list
Add accessors for the me client properties from host client.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: revamp client connection

Simplify connect state machine by changing the logic around
Connection request in progress - only check if we have a callback in
relevant queue.
Extract common code into mei_cl_send_connect() function

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: revamp client disconnection flow

Split disconnected state into two parts first reception disconnect
response from the firmware and second actually setting of disconnected
state. Book keeping data are needed for processing and after firmware
disconnected the client and are cleaned when setting the disconnected
state in mei_cl_set_disconneted() function.
Add mei_cl_send_disconnect to reduce code duplication.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: use mei_cl_is_connected consistently

Replace open coded check for cl->state !=/== MEI_FILE_CONNECTED
with mei_cl_is_connected function.

Note that cl->state != MEI_FILE_CONNECTED is not the same
as cl->state == MEI_FILE_DISCONNECTED

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: fix mei_poll operation

mei_poll returned with POLLIN w/o checking whether the operation
has really completed.
remove redundant check and locking in amthif specific handler

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: free me client references on host init

Fx fixes leak introduced by:
commit b7d885145538 ("mei: revamp me clients list handling")

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: allow read concurrency

Replace clunky read state machine with read stack
implemented as per client read list, this is important
mostly for mei drivers with unsolicited reads

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: simplify io callback disposal

Simplify disposal of io callback by removing the callback
implicitly from its lookup list inside mei_io_cb_free

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: add mei_cl_alloc_linked function

Add convenient wrapper mei_cl_alloc_linked
to simplify error handling

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: always initialize the callback with the intended operation type

We set the operation type at initialization time as each cb is used only
for a single type of operation

As a byproduct we add a convenient wrapper for allocating cb with
the data buffer.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: use only one buffer in callback

The callback structure is used exclusively for reading or writing
therefore there is no reason to hold both response and request buffers
in the callback structure

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: iamthif: use client write functions

Reduce code duplication in amthif code by reusing
regular client write functions.
Add completed flag to cb so amthif client can add
rx credits on write completion

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: fix function names and format in KDoc

Align functions names in KDoc with real ones.
Fix comment format to be KDoc and fix wrong syntax there.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: revamp me clients list handling

1. Use rw lock to access the me_clients list

2. Reuse already defined find functions also when
removing particular me client

3. Add wrappers for addition and deletion

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: add reference counting for me clients

To support dynamic addition and removal of
me clients we add reference counter.

Update kdoc with locking requirements.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: use uuid, me_addr tuple addressing also for flow control credits

Add uuid, me_addr addressing also for flow control credits.
The only exception in cases for single buffer clients for which
the host address in flow credits response is always 0

To in order to deal with add/remove race between fw and driver clients
addressing we need to use [uuid, me_addr] tuple to address the clients

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: drop unneeded client NULL check in cb structure

The pointer to client in the callback structure (cb->cl)
can't be NULL with current locking.
We can drop check and warnings as in some cases this just
uselessly complicates the code flow.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: fix kernel-doc warnings

Add missed parameters descriptions and return values descriptions

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: fix KDoc documentation formatting

Fix Kdoc documentation formatting warnings
genertaed by ./scripts/kernel-doc

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: trivial: fix errors in prints in comments

Fix misspellings and wrong print texts

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: remove include to pci header from mei module files

Remove inclusion of linux/pci.h in mei layer
however we need to include the headers that before
got included implicitly from linux/pci.h.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: get rid of most of the pci dependencies in mei

For purpose of adding testing HW we would like
to get rid of pci dependency in generic mei code
This patch provides only straight forward changes
FW status and prob quirks need to be handled separately

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: fix style warning: Missing a blank line after declarations

fix new style warning: Missing a blank line after declarations

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: revamp connect and disconnect response handling

Both responses have same flow only the client status
update is different. We introduce handler mei_hbm_cl_res()
that handles both responses
Also we use per client wait queue (cl->wait) rather then
global dev->wait_recvd_msg

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: use disconnect name consistently

Rename mei_cl_irq_close to mei_cl_irq_disconnect
and MEI_FOP_CLOSE to MEI_FOP_DISCONNECT
Remove unused MEI_FOP_OPEN

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: add mei_me_cl_by_uuid_id function

When handling dynamic clients there might be a race
scenario in which two me clients with the same me
address would be linked in the me clients list,
therefore we need to search by both uuid and me address.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: add me client remove functions

To support dynamic addition/remove we add wrappers
for removal of me clients

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: use list for me clients book keeping

To support dynamic addition/remove of clients
it is more convenient to use list instead of
static array

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: me_client lookup function to return me_client object

For support of dynamic addition and removal of me clients
it is more convenient to use a list instead of static array
as is use now.
As the first step of the transition to the new data structure
we change the lookup function so it returns me client address
instead of an index.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: amthif: use service function to flush amthif queue

Replace open coded loop with an existing service function:
mei_io_list_flush

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: reset client state on queued connect request

If connect request is queued (e.g. device in pg) set client state
to initializing, thus avoid preliminary exit in wait if current
state is disconnected.

This is regression from:

commit e4d8270e604c3202131bac607969605ac397b893
Author: Alexander Usyskin <alexander.usyskin@intel.com>
mei: set connecting state just upon connection request is sent to the fw

CC: stable@vger.kernel.org # 3.15+
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: fix return value on disconnect timeout

wait_event_timeout can return 0 or the remaining jiffies
so return -ETIME if disconnected state not reached.

Cc: stable@vger.kernel.org # 3.10+
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: start disconnect request timer consistently

Link must be reset in case the fw doesn't
respond to client disconnect request.
We did charge the timer only in irq path
from mei_cl_irq_close and not in mei_cl_disconnect

Cc: stable@vger.kernel.org # 3.10+
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: reset client connection state on timeout

On connection timeout we leave the connecting client in
connecting state. Since a new connection is stalled till
previous connection is completed in this case no new connection
is possible till the user space does release the file handle.
Therefore on timeout we move the client to disconnected state.

Cc: stable@vger.kernel.org # 3.15+
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: set connecting state just upon connection request is sent to the fw

Adding power gating introduced new waiting state for client also during
connection attempt, a connection request can be queued for later either due
device is power gated or due to other on going connection.
We setting client connection state before start of full connect procedure so
in both cased the client state will be MEI_FILE_CONNECTING
which create interlock between the two connection attempts, both
detecting that another connection is in progress.

The interlock is resolved by moving client to connecting state
only upon connection request transmission, so the first
cb in queue can be processed.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: make return values consistent across the driver

Follow-up for bits missed in
commit 7ca96aa278f8b9983184e318b06a0ed9ad0297b8
mei: make return values consistent across the driver

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: use runtime pm in write and read flow

Take rpm token on operation start to initiate rpm resume if needed.
Mark last busy time, release token and advice rpm framework
to try to autosuspend on operation end.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: fix memory leak of pending write cb objects

Write callbacks are released on the write completed path but
when file handler is closed before the writes are
completed those are left dangling on write and write_waiting queues.

We add mei_io_list_free function to perform this task

Also move static functions to client.c form client.h

Cc: stable <stable@vger.kernel.org> # 3.11+
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: make return values consistent across the driver

1. Propagate ENOTTY to user space if the client is not present
in the system
2. Use ETIME consistently on timeouts
3. Return EIO on write failures
4. Return ENODEV on recoverable device failures such as resets

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: revamp writing slot counting

Since txe use doorbell and not circular buffer
we have to cheat in write slot counting, txe always consume all the
slots upon write. In order for it to work we need to track
slots using mei_hbuf_empty_slots() instead of tracking it in mei layer

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: add mei_hbuf_acquire wrapper

A client has to acquire host buffer
before writing, we add lock like wrapper
to replace the code snippet

if (dev->hbuf_is_ready)
dev->hbuf_is_ready = false;

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: set client's read_cb to NULL when flow control fails

In mei_cl_read_start(), if it fails to send flow control request, it
will release "cl->read_cb" but forget to set pointer to NULL, leaving
"cl->read_cb" still pointing to random memory, next time this client is
operated like mei_release(), it has chance to refer to this wrong pointer.

Fixes: PANIC at kfree in mei_release()

[228781.826904] Call Trace:
[228781.829737] [<c16249b8>] ? mei_cl_unlink+0x48/0xa0
[228781.835283] [<c1624487>] mei_io_cb_free+0x17/0x30
[228781.840733] [<c16265d8>] mei_release+0xa8/0x180
[228781.845989] [<c135c610>] ? __fsnotify_parent+0xa0/0xf0
[228781.851925] [<c1325a69>] __fput+0xd9/0x200
[228781.856696] [<c1325b9d>] ____fput+0xd/0x10
[228781.861467] [<c125cae1>] task_work_run+0x81/0xb0
[228781.866821] [<c1242e53>] do_exit+0x283/0xa00
[228781.871786] [<c1a82b36>] ? kprobe_flush_task+0x66/0xc0
[228781.877722] [<c124eeb8>] ? __dequeue_signal+0x18/0x1a0
[228781.883657] [<c124f072>] ? dequeue_signal+0x32/0x190
[228781.889397] [<c1243744>] do_group_exit+0x34/0xa0
[228781.894750] [<c12517b6>] get_signal_to_deliver+0x206/0x610
[228781.901075] [<c12018d8>] do_signal+0x38/0x100
[228781.906136] [<c1626d1c>] ? mei_read+0x42c/0x4e0
[228781.911393] [<c12600a0>] ? wake_up_bit+0x30/0x30
[228781.916745] [<c16268f0>] ? mei_poll+0x120/0x120
[228781.922001] [<c1324be9>] ? vfs_read+0x89/0x160
[228781.927158] [<c16268f0>] ? mei_poll+0x120/0x120
[228781.932414] [<c133ca34>] ? fget_light+0x44/0xe0
[228781.937670] [<c1324e58>] ? SyS_read+0x68/0x80
[228781.942730] [<c12019f5>] do_notify_resume+0x55/0x70
[228781.948376] [<c1a7de5d>] work_notifysig+0x29/0x30
[228781.953827] [<c1a70000>] ? bad_area+0x5/0x3e

Cc: stable <stable@vger.kernel.org> # 3.9+
Signed-off-by: Chao Bi <chao.bi@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: don't of list_for_each_entry_safe when not deleting

We can use simply list_for_each_entry if there is no
entry removal

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: use helper function to find me client by id

We already have a helper to find me client by id, let's
use it in all relevant places.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: fix potential read outside of array bounds

Drop not-very-useful check and with this
fix read on index that can be after array end.
Cleanup search function as byproduct.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: hbm: revamp client connect and disconnection status

1. Return -ENOTTY on client connect if the requested client was not found
on the enumeration list or the client was internally disabled, in the later
case FW will return NOT_FOUND.
2. Return -EBUSY if the client cannot be connected because of resource
contention
3. Change response status enum to have MEI_CL_ prefix
4. Add function to translate response status to a string
for more readable logging

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: rename MEI_FOP_IOCTL to MEI_FOP_CONNECT

This operation actually only support connection
and not a generic ioctl

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: don't unset read cb ptr on reset

Don't set read callback to NULL during reset as
this leads to memory leak of both cb and its buffer.
The memory is correctly freed during mei_release.

The memory leak is detectable by kmemleak if
application has open read call while system is going through
suspend/resume.

unreferenced object 0xecead780 (size 64):
comm "AsyncTask #1", pid 1018, jiffies 4294949621 (age 152.440s)
hex dump (first 32 bytes):
00 01 10 00 00 02 20 00 00 bf 30 f1 00 00 00 00 ...... ...0.....
00 00 00 00 00 00 00 00 36 01 00 00 00 70 da e2 ........6....p..
backtrace:
[<c1a60aec>] kmemleak_alloc+0x3c/0xa0
[<c131ed56>] kmem_cache_alloc_trace+0xc6/0x190
[<c16243c9>] mei_io_cb_init+0x29/0x50
[<c1625722>] mei_cl_read_start+0x102/0x360
[<c16268f3>] mei_read+0x103/0x4e0
[<c1324b09>] vfs_read+0x89/0x160
[<c1324d5f>] SyS_read+0x4f/0x80
[<c1a7b318>] syscall_call+0x7/0xb
[<ffffffff>] 0xffffffff
unreferenced object 0xe2da7000 (size 512):
comm "AsyncTask #1", pid 1018, jiffies 4294949621 (age 152.440s)
hex dump (first 32 bytes):
00 6c da e2 7c 00 00 00 00 00 00 00 c0 eb 0c 59 .l..|..........Y
1b 00 00 00 01 00 00 00 02 10 00 00 01 00 00 00 ................
backtrace:
[<c1a60aec>] kmemleak_alloc+0x3c/0xa0
[<c131f127>] __kmalloc+0xe7/0x1d0
[<c162447e>] mei_io_cb_alloc_resp_buf+0x2e/0x60
[<c162574c>] mei_cl_read_start+0x12c/0x360
[<c16268f3>] mei_read+0x103/0x4e0
[<c1324b09>] vfs_read+0x89/0x160
[<c1324d5f>] SyS_read+0x4f/0x80
[<c1a7b318>] syscall_call+0x7/0xb
[<ffffffff>] 0xffffffff

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: clear write cb from waiting list on reset

Clear write callbacks sitting in write_waiting list on reset.
Otherwise these callbacks are left dangling and cause memory leak.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: limit the number of consecutive resets

give up reseting after 3 unsuccessful tries

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: fix syntax in comments and debug output

Fix syntax errors in comments and debug strings

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: enable marking internal commands

Set hbm header bit 30 for internal commands
This mark commands that are generated by
the device driver

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: drop redundant list_del_init

list_del_init appears twice in row in mei_cl_unlink, drop one.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: mei_cl_link remove duplicated check for open_handle_count

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: move host_clients_map cleanup to device init

Move host_clients_map cleanup from host client init to device init.

This fixes bug where we cleaned up the bitmask that servers as pool for
host client ids while file descriptors are kept open during suspend.
On resume a new connection will be assigned id that is already taken
by opened file descriptor. Consequently read/write will fail due to
mismatched book keeping.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: revamp open handler counts

Make open counter to be incremented and decremented
from mei_cl_link and mei_cl_unlik function respectively

Nfc was assuming symmetric linking API and thus open handler
count was never decreased. This patch fixes that.
We need to add separate open hander count for amthif which
is handled out of link/unlink functions and doesn't break
the symmetric API.

Last we do not waste clients slots if amthif or wd are not present
in the device. we don't need to allocates slots ahead
it is all covered by link/unlink before the devices is responding
to user space connection and thus not racing on allocation

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: simplify mei_open error handling

1. Perform simple checks first and only then attempt to allocate cl structure.
2. Remove open_handler_count test, this is already checked in mei_cl_link function
3. return -EMFILE instead of -ENOENT as expected by user space

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: mei_cl_unlink: no need to loop over dev list

we can call list_del_init regardless the client is
linked or not it is always properly initialized

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: push credentials inside the irq write handler

this eventually allows as use a single write queue
both for control and data messages and removing possible
race

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: propagate error from write routines instead of ENODEV

ENODEV will cause application to try to reconnect since
it assumes that device went through the reset
write errors are not always fatal it can happen due to
resource contention

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: prefix client log messages with client me and host ids

define cl_dbg and cl_err macros that add me and host id
prefix for debug and error log messages so we can track
for the client context of the flow.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: mei_cl_link protect open_handle_count from overflow

mei_cl_link is called both from mei_open and also from
in-kernel drivers so we need to protect open_handle_count
from overflow

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: don't get stuck in select during reset

Clear pending connection after hw reset but before hw start
and wake up the waiting task in poll. Signal POLLERR in select
when device went through reset.

Add wrapper mei_cl_is_connected for checking if
the device and client are connected.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: wake also writers on reset

wake writers otherwise might have processes waiting
endlessly on wait_tx during reset

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: mei_cl_connect: don't multiply the timeout twice

MEI_CL_CONNECT_TIMEOUT is the timeout in seconds to wait
for a response in mei_cl_connect.
The value was converted to jiffies using mei_secs_to_jiffies
helper function and assigned to a local variable
which is by mistake again multiplied by HZ

Signed-off-by: Frode Isaksen <frodex.isaksen@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: do not override a client writing state when buffering

when we buffer write request we should not switch to
MEI_WRITING since this will override MEI_WRITE_COMPLETE
state of preceding write

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: move mei_cl_irq_write_complete to client.c

mei_cl_irq_write_complete operates on a client so move it
to client.c

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: move mei_cl_complete to client.c

1. rename mei_cl_complete_handler to mei_cl_complete
2. move the function client.c where it belongs

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: fix reading large reposnes

While writting to device is limitted to max_msg_length advertized
in client properites the read can be much longer delivered consequiting chunks.

We use krealloc to enlarge the buffer when needed.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: nfc: Initial nfc implementation

NFC ME device is exported through the MEI bus to be consumed by the
NFC subsystem.

NFC is represented by two mei clients: An info one and the actual
NFC one. In order to properly build the ME id we first need to retrieve
the firmware information from the info client and then disconnect from it.

Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: add mei_cl_write function

consolidate write code to a specific me client in mei_cl_write function
the function is called from mei device write handler and from
mei_cl bus send function

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: Fix comments in drivers/misc/mei

Correct typos and fix stray comments.

Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Acked-by: Winkler, Tomas <tomas.winkler@intel.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

mei: bus: Add bus related structures to mei_cl

We keep track of all MEI devices on the bus through a specific linked list.
We also have a mei_device instance in the mei_cl structure.

Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: move clients cleanup code from init.c to client.c

during reset we clean up client data structures
we move that code into wrappers in client
and call the wrappers

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: rename to mei_host_buffer_is_empty to hbuf_is_ready

we rename the mei_host_buffer_is_empty to keep naming
convention of hbuf and also make the query more generic
to be correct also for other under laying hardware

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: drop the warning when cl is not initialized during unlinking

On systems where wd and amthif is not initialized
we will hit cl->dev == NULL. This condition is okay
so we don't need to be laud about it.

Fixes the follwing warning during suspend
[ 137.061985] WARNING: at drivers/misc/mei/client.c:315 mei_cl_unlink+0x86/0x90 [mei]()
[ 137.061986] Hardware name: 530U3BI/530U4BI/530U4BH
[ 137.062140] Modules linked in: snd_hda_codec_hdmi snd_hda_codec_realtek joydev coretemp kvm_intel snd_hda_intel snd_hda_codec kvm arc4 iwldvm snd_hwdep i915 snd_pcm mac80211 ghash_clmulni_intel snd_page_alloc aesni_intel snd_seq_midi xts snd_seq_midi_event aes_x86_64 rfcomm snd_rawmidi parport_pc bnep lrw snd_seq uvcvideo i2c_algo_bit ppdev gf128mul iwlwifi snd_timer drm_kms_helper ablk_helper cryptd drm snd_seq_device videobuf2_vmalloc psmouse videobuf2_memops snd cfg80211 btusb videobuf2_core soundcore videodev lp bluetooth samsung_laptop wmi microcode mei serio_raw mac_hid video hid_generic lpc_ich parport usbhid hid r8169
[ 137.062143] Pid: 2706, comm: kworker/u:15 Tainted: G D W 3.8.0-rc2-next20130109-1-iniza-generic #1
[ 137.062144] Call Trace:
[ 137.062156] [<ffffffff8105860f>] warn_slowpath_common+0x7f/0xc0
[ 137.062159] [<ffffffff8135b1ea>] ? ioread32+0x3a/0x40
[ 137.062162] [<ffffffff8105866a>] warn_slowpath_null+0x1a/0x20
[ 137.062168] [<ffffffffa0076be6>] mei_cl_unlink+0x86/0x90 [mei]
[ 137.062173] [<ffffffffa0071325>] mei_reset+0xc5/0x240 [mei]
[ 137.062178] [<ffffffffa0073703>] mei_pci_resume+0xa3/0x110 [mei]
[ 137.062183] [<ffffffff81379cae>] pci_pm_resume+0x7e/0xe0
[ 137.062185] [<ffffffff81379c30>] ? pci_pm_thaw+0x80/0x80
[ 137.062189] [<ffffffff8145a415>] dpm_run_callback.isra.6+0x25/0x50
[ 137.062192] [<ffffffff8145a6cf>] device_resume+0x9f/0x140
[ 137.062194] [<ffffffff8145a791>] async_resume+0x21/0x50
[ 137.062200] [<ffffffff810858b0>] async_run_entry_fn+0x90/0x1c0
[ 137.062203] [<ffffffff810778e5>] process_one_work+0x155/0x460
[ 137.062207] [<ffffffff81078578>] worker_thread+0x168/0x400
[ 137.062210] [<ffffffff81078410>] ? manage_workers+0x2b0/0x2b0
[ 137.062214] [<ffffffff8107d9f0>] kthread+0xc0/0xd0
[ 137.062218] [<ffffffff8107d930>] ? flush_kthread_worker+0xb0/0xb0
[ 137.062222] [<ffffffff816bac6c>] ret_from_fork+0x7c/0xb0
[ 137.062228] [<ffffffff8107d930>] ? flush_kthread_worker+0xb0/0xb0

Reported-by: Sedat Dilek <sedat.dilek@gmail.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: normalize me host client linking routines

In order we can use the same code pattern for in-kernel
and user space host clients we replace mei_cl_link_to_me
with mei_cl_link function.
We then have to keep me client lookupout of the new link function.

The unlinking cannot be yet symetric due to amthif connection
handling

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: rename remaining amthi strings to amthif

the only real thing that left was mei_amthi_guid
the rest was in the strings and comments

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: drop read_pending member form struct mei_cl

read_pending never changes, it is a leftover from the old code.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: rename interface to hw-me

Rename hw-me.h to hw-me-regs.h as this file
contains only register definitions.
Files hw-me.[ch] now contains ME hw dependant
functionality

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: implement mei_cl_connect function

Implement mei_cl_connect that warps host client
parts of the connection and leave the ioctl specifics
in the mei_ioctl_connect_client function.
Move mei_ioctl_connect_client to main.c where it
belongs

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: fix client functions names

Use common prefix for function names:

mei_cl_ - for host clients
mei_me_ - for me clients
mei_io_ - for io callback functions

Because mei_cl holds mei_device back pointer
we can also drop the dev argument from the client
functions

add client.h header to export the clients API

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mei: move client functions to client.c

This file now contains me and host client functions
and also io callback helpers
We also kill iorw.c which is no longer needed

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>