Commit Graph

21 Commits

Author SHA1 Message Date
Shengjiu Wang f061773b7b rpmsg: char: Add mutex protection for rpmsg_eptdev_open()
[ Upstream commit abe13e9a56 ]

There is no mutex protection for rpmsg_eptdev_open(),
especially for eptdev->ept read and write operation.
It may cause issues when multiple instances call
rpmsg_eptdev_open() in parallel,the return state
may be success or EBUSY.

Fixes: 964e8bedd5 ("rpmsg: char: Return an error if device already open")
Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>
Link: https://lore.kernel.org/r/1653104105-16779-1-git-send-email-shengjiu.wang@nxp.com
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-17 14:24:03 +02:00
Matthias Kaehlcke daf9ac79e7 rpmsg: char: Fix race between the release of rpmsg_eptdev and cdev
commit 7a534ae89e upstream.

struct rpmsg_eptdev contains a struct cdev. The current code frees
the rpmsg_eptdev struct in rpmsg_eptdev_destroy(), but the cdev is
a managed object, therefore its release is not predictable and the
rpmsg_eptdev could be freed before the cdev is entirely released.

The cdev_device_add/del() API was created to address this issue
(see commit '233ed09d7fda ("chardev: add helper function to register
char devs with a struct device")'), use it instead of cdev add/del().

Fixes: c0cdc19f84 ("rpmsg: Driver for user space endpoint interface")
Suggested-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20220110104706.v6.2.Idde68b05b88d4a2e6e54766c653f3a6d9e419ce6@changeid
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-02-01 17:27:07 +01:00
Sujit Kautkar 85aba11a8e rpmsg: char: Fix race between the release of rpmsg_ctrldev and cdev
commit b7fb2dad57 upstream.

struct rpmsg_ctrldev contains a struct cdev. The current code frees
the rpmsg_ctrldev struct in rpmsg_ctrldev_release_device(), but the
cdev is a managed object, therefore its release is not predictable
and the rpmsg_ctrldev could be freed before the cdev is entirely
released, as in the backtrace below.

[   93.625603] ODEBUG: free active (active state 0) object type: timer_list hint: delayed_work_timer_fn+0x0/0x7c
[   93.636115] WARNING: CPU: 0 PID: 12 at lib/debugobjects.c:488 debug_print_object+0x13c/0x1b0
[   93.644799] Modules linked in: veth xt_cgroup xt_MASQUERADE rfcomm algif_hash algif_skcipher af_alg uinput ip6table_nat fuse uvcvideo videobuf2_vmalloc venus_enc venus_dec videobuf2_dma_contig hci_uart btandroid btqca snd_soc_rt5682_i2c bluetooth qcom_spmi_temp_alarm snd_soc_rt5682v
[   93.715175] CPU: 0 PID: 12 Comm: kworker/0:1 Tainted: G    B             5.4.163-lockdep #26
[   93.723855] Hardware name: Google Lazor (rev3 - 8) with LTE (DT)
[   93.730055] Workqueue: events kobject_delayed_cleanup
[   93.735271] pstate: 60c00009 (nZCv daif +PAN +UAO)
[   93.740216] pc : debug_print_object+0x13c/0x1b0
[   93.744890] lr : debug_print_object+0x13c/0x1b0
[   93.749555] sp : ffffffacf5bc7940
[   93.752978] x29: ffffffacf5bc7940 x28: dfffffd000000000
[   93.758448] x27: ffffffacdb11a800 x26: dfffffd000000000
[   93.763916] x25: ffffffd0734f856c x24: dfffffd000000000
[   93.769389] x23: 0000000000000000 x22: ffffffd0733c35b0
[   93.774860] x21: ffffffd0751994a0 x20: ffffffd075ec27c0
[   93.780338] x19: ffffffd075199100 x18: 00000000000276e0
[   93.785814] x17: 0000000000000000 x16: dfffffd000000000
[   93.791291] x15: ffffffffffffffff x14: 6e6968207473696c
[   93.796768] x13: 0000000000000000 x12: ffffffd075e2b000
[   93.802244] x11: 0000000000000001 x10: 0000000000000000
[   93.807723] x9 : d13400dff1921900 x8 : d13400dff1921900
[   93.813200] x7 : 0000000000000000 x6 : 0000000000000000
[   93.818676] x5 : 0000000000000080 x4 : 0000000000000000
[   93.824152] x3 : ffffffd0732a0fa4 x2 : 0000000000000001
[   93.829628] x1 : ffffffacf5bc7580 x0 : 0000000000000061
[   93.835104] Call trace:
[   93.837644]  debug_print_object+0x13c/0x1b0
[   93.841963]  __debug_check_no_obj_freed+0x25c/0x3c0
[   93.846987]  debug_check_no_obj_freed+0x18/0x20
[   93.851669]  slab_free_freelist_hook+0xbc/0x1e4
[   93.856346]  kfree+0xfc/0x2f4
[   93.859416]  rpmsg_ctrldev_release_device+0x78/0xb8
[   93.864445]  device_release+0x84/0x168
[   93.868310]  kobject_cleanup+0x12c/0x298
[   93.872356]  kobject_delayed_cleanup+0x10/0x18
[   93.876948]  process_one_work+0x578/0x92c
[   93.881086]  worker_thread+0x804/0xcf8
[   93.884963]  kthread+0x2a8/0x314
[   93.888303]  ret_from_fork+0x10/0x18

The cdev_device_add/del() API was created to address this issue (see
commit '233ed09d7fda ("chardev: add helper function to register char
devs with a struct device")'), use it instead of cdev add/del().

Fixes: c0cdc19f84 ("rpmsg: Driver for user space endpoint interface")
Signed-off-by: Sujit Kautkar <sujitka@chromium.org>
Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20220110104706.v6.1.Iaac908f3e3149a89190ce006ba166e2d3fd247a3@changeid
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-02-01 17:27:07 +01:00
Arnaud Pouliquen 964e8bedd5 rpmsg: char: Return an error if device already open
The rpmsg_create_ept function is invoked when the device is opened.
As only one endpoint must be created per device. It is not possible to
open the same device twice. But there is nothing to prevent multi open.
Return -EBUSY when device is already opened to have a generic error
instead of relying on the back-end to potentially detect the error.

Without this patch for instance the GLINK driver return -EBUSY while
the virtio bus return -ENOSPC.

Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@foss.st.com>
Link: https://lore.kernel.org/r/20210311140413.31725-7-arnaud.pouliquen@foss.st.com
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
2021-03-17 14:16:58 -05:00
Arnaud Pouliquen b4ce7e2ebc rpmsg: char: Use rpmsg_sendto to specify the message destination address
When the endpoint device is created by the application, a destination
address is specified in the rpmsg_channel_info structure. Since the
rpmsg_endpoint structure does not store the destination address,
this destination address must be specified when sending a message.

Replaces rpmsg_send with rpmsg_sendto to allow to specify the
destination address. This implementation is requested for compatibly with
some rpmsg backends like the virtio backend.

For this, the GLINK an SMD drivers have been updated to support the
rpmsg_sendto, even if the destination address is ignored for these
backends. For these drivers, the rpmsg_send and rpmsg_trysend ops are
preserved to avoid breaking the legacy.

Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@foss.st.com>

Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Link: https://lore.kernel.org/r/20210311140413.31725-5-arnaud.pouliquen@foss.st.com
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
2021-03-17 14:16:36 -05:00
Arnaud Pouliquen 60d7b22d25 rpmsg: char: Rename rpmsg_char_init to rpmsg_chrdev_init
To be coherent with the other functions which are prefixed by
rpmsg_chrdev, rename the rpmsg_char_init function.

Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@foss.st.com>
Link: https://lore.kernel.org/r/20210311140413.31725-2-arnaud.pouliquen@foss.st.com
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
2021-03-17 14:16:04 -05:00
Linus Torvalds 687fcad8a3 rpmsg updates for v5.5
This contains a number of bug fixes to the GLINK transport driver, an
 off-by-one in the GLINK smem driver and a memory leak fix in the rpmsg
 char driver.
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Merge tag 'rpmsg-v5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/andersson/remoteproc

Pull rpmsg updates from Bjorn Andersson:
 "This contains a number of bug fixes to the GLINK transport driver, an
  off-by-one in the GLINK smem driver and a memory leak fix in the rpmsg
  char driver"

* tag 'rpmsg-v5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/andersson/remoteproc:
  rpmsg: Fix Kconfig indentation
  rpmsg: char: Simplify 'rpmsg_eptdev_release()'
  rpmsg: glink: Free pending deferred work on remove
  rpmsg: glink: Don't send pending rx_done during remove
  rpmsg: glink: Fix rpmsg_register_device err handling
  rpmsg: glink: Put an extra reference during cleanup
  rpmsg: glink: Fix use after free in open_ack TIMEOUT case
  rpmsg: glink: Fix reuse intents memory leak issue
  rpmsg: glink: Set tail pointer to 0 at end of FIFO
  rpmsg: char: release allocated memory
2019-12-01 18:39:24 -08:00
Christophe JAILLET bb06a5ce88 rpmsg: char: Simplify 'rpmsg_eptdev_release()'
Use 'skb_queue_purge()' instead of re-implementing it.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
2019-11-08 16:49:37 -08:00
Arnd Bergmann 1832f2d8ff compat_ioctl: move more drivers to compat_ptr_ioctl
The .ioctl and .compat_ioctl file operations have the same prototype so
they can both point to the same function, which works great almost all
the time when all the commands are compatible.

One exception is the s390 architecture, where a compat pointer is only
31 bit wide, and converting it into a 64-bit pointer requires calling
compat_ptr(). Most drivers here will never run in s390, but since we now
have a generic helper for it, it's easy enough to use it consistently.

I double-checked all these drivers to ensure that all ioctl arguments
are used as pointers or are ignored, but are not interpreted as integer
values.

Acked-by: Jason Gunthorpe <jgg@mellanox.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: David Sterba <dsterba@suse.com>
Acked-by: Darren Hart (VMware) <dvhart@infradead.org>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Acked-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2019-10-23 17:23:44 +02:00
Navid Emamdoost bbe692e349 rpmsg: char: release allocated memory
In rpmsg_eptdev_write_iter, if copy_from_iter_full fails the allocated
buffer needs to be released.

Signed-off-by: Navid Emamdoost <navid.emamdoost@gmail.com>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
2019-10-04 21:13:47 -07:00
Bjorn Andersson ccf45b18ce rpmsg: char: Migrate to iter versions of read and write
In order to be able to use the aio interface for writing to a rpmsg_char
the write_iter function must be implemented, so migrate to iter version
for read and write functions.

Regular read and write uses the iter methods if present and is as such
unaffected.

Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
2018-08-27 17:06:57 -07:00
Arun Kumar Neelakantam 00b645e0b4 rpmsg: Add compat ioctl for rpmsg char driver
Add compat ioctl callback to support 32bit user space applications.

Signed-off-by: Arun Kumar Neelakantam <aneela@codeaurora.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
2018-07-30 23:40:23 -07:00
Suman Anna 136200f4fd rpmsg: char: Switch to SPDX license identifier
Use the appropriate SPDX license identifier in the rpmsg char driver
source file and drop the previous boilerplate license text. The uapi
header file already had the SPDX license identifier added as part of
a mass update but the license text removal was deferred for later,
and this patch drops the same.

Signed-off-by: Suman Anna <s-anna@ti.com>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
2018-06-03 17:37:16 -07:00
Ramon Fried 93dd4e73c0 rpmsg: added MODULE_ALIAS for rpmsg_char
Added "rpmsg:rpmsg_chrdev" MODULE_ALIAS to autoload
rpmg_chrdev module automatically.

Signed-off-by: Ramon Fried <rfried@codeaurora.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
2018-04-25 16:46:55 -07:00
Linus Torvalds a9a08845e9 vfs: do bulk POLL* -> EPOLL* replacement
This is the mindless scripted replacement of kernel use of POLL*
variables as described by Al, done by this script:

    for V in IN OUT PRI ERR RDNORM RDBAND WRNORM WRBAND HUP RDHUP NVAL MSG; do
        L=`git grep -l -w POLL$V | grep -v '^t' | grep -v /um/ | grep -v '^sa' | grep -v '/poll.h$'|grep -v '^D'`
        for f in $L; do sed -i "-es/^\([^\"]*\)\(\<POLL$V\>\)/\\1E\\2/" $f; done
    done

with de-mangling cleanups yet to come.

NOTE! On almost all architectures, the EPOLL* constants have the same
values as the POLL* constants do.  But they keyword here is "almost".
For various bad reasons they aren't the same, and epoll() doesn't
actually work quite correctly in some cases due to this on Sparc et al.

The next patch from Al will sort out the final differences, and we
should be all done.

Scripted-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-02-11 14:34:03 -08:00
Al Viro afc9a42b74 the rest of drivers/*: annotate ->poll() instances
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-11-28 11:06:58 -05:00
Linus Torvalds 426b8eeb05 rpmsg updates for v4.13
This introduces the Qualcomm GLINK protocol driver and DeviceTree-based
 modalias support, as well as a number of smaller fixes.
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Merge tag 'rpmsg-v4.13' of git://github.com/andersson/remoteproc

Pull rpmsg updates from Bjorn Andersson:
 "This introduces the Qualcomm GLINK protocol driver and
  DeviceTree-based modalias support, as well as a number of smaller
  fixes"

* tag 'rpmsg-v4.13' of git://github.com/andersson/remoteproc:
  rpmsg: Make modalias work for DeviceTree based devices
  rpmsg: Drop VIRTUALIZATION dependency from RPMSG_VIRTIO
  rpmsg: Don't overwrite release op of rpdev
  rpmsg: virtio_rpmsg_bus: cleanup multiple assignment to ops
  rpmsg: virtio_rpmsg_bus: fix nameservice address
  rpmsg: cleanup incorrect function in dev_err message
  rpmsg: virtio_rpmsg_bus: fix announce for devices without endpoint
  rpmsg: Introduce Qualcomm RPM glink driver
  soc: qcom: Add device tree binding for GLINK RPM
  rpmsg: Release rpmsg devices in backends
2017-07-06 15:38:31 -07:00
Henri Roosen f6175294ab rpmsg: cleanup incorrect function in dev_err message
Trivial cleanup for incorrect function in dev_err message

Signed-off-by: Henri Roosen <henri.roosen@ginzinger.com>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
2017-06-25 14:36:16 -07:00
Johannes Berg 59ae1d127a networking: introduce and use skb_put_data()
A common pattern with skb_put() is to just want to memcpy()
some data into the new space, introduce skb_put_data() for
this.

An spatch similar to the one for skb_put_zero() converts many
of the places using it:

    @@
    identifier p, p2;
    expression len, skb, data;
    type t, t2;
    @@
    (
    -p = skb_put(skb, len);
    +p = skb_put_data(skb, data, len);
    |
    -p = (t)skb_put(skb, len);
    +p = skb_put_data(skb, data, len);
    )
    (
    p2 = (t2)p;
    -memcpy(p2, data, len);
    |
    -memcpy(p, data, len);
    )

    @@
    type t, t2;
    identifier p, p2;
    expression skb, data;
    @@
    t *p;
    ...
    (
    -p = skb_put(skb, sizeof(t));
    +p = skb_put_data(skb, data, sizeof(t));
    |
    -p = (t *)skb_put(skb, sizeof(t));
    +p = skb_put_data(skb, data, sizeof(t));
    )
    (
    p2 = (t2)p;
    -memcpy(p2, data, sizeof(*p));
    |
    -memcpy(p, data, sizeof(*p));
    )

    @@
    expression skb, len, data;
    @@
    -memcpy(skb_put(skb, len), data, len);
    +skb_put_data(skb, data, len);

(again, manually post-processed to retain some comments)

Reviewed-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-16 11:48:37 -04:00
Dan Carpenter 0abd6bdde0 rpmsg: unlock on error in rpmsg_eptdev_read()
We should unlock before returning if skb_dequeue() returns a NULL.

Fixes: c0cdc19f84 ("rpmsg: Driver for user space endpoint interface")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
2017-01-30 13:20:24 -08:00
Bjorn Andersson c0cdc19f84 rpmsg: Driver for user space endpoint interface
This driver allows rpmsg instances to expose access to rpmsg endpoints
to user space processes. It provides a control interface, allowing
userspace to export endpoints and an endpoint interface for each exposed
endpoint.

The implementation is based on prior art by Texas Instrument, Google,
PetaLogix and was derived from a FreeRTOS performance statistics driver
written by Michal Simek.

The control interface provides a "create endpoint" ioctl, which is fed a
name, source and destination address. The three values are used to
create the endpoint, in a backend-specific way, and a rpmsg endpoint
device is created - with the three parameters are available in sysfs for
udev usage.

E.g. to create an endpoint device for one of the Qualcomm SMD channel
related to DIAG one would issue:

  struct rpmsg_endpoint_info info = { "DIAG_CNTL", 0, 0 };
  int fd = open("/dev/rpmsg_ctrl0", O_RDWR);
  ioctl(fd, RPMSG_CREATE_EPT_IOCTL, &info);

Each created endpoint device shows up as an individual character device
in /dev, allowing permission to be controlled on a per-endpoint basis.
The rpmsg endpoint will be created and destroyed following the opening
and closing of the endpoint device, allowing rpmsg backends to open and
close the physical channel, if supported by the wire protocol.

Cc: Marek Novak <marek.novak@nxp.com>
Cc: Matteo Sartori <matteo.sartori@t3lab.it>
Cc: Michal Simek <monstr@monstr.eu>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
2017-01-18 10:43:15 -08:00