Commit Graph

16 Commits

Author SHA1 Message Date
Todd Poynor
bfec1de4fe staging: gasket: sysfs: fix function param line continuation style
Fix multi-line alignment formatting to look like:
      int ret = long_function_name(device, VARIABLE1, VARIABLE2,
                                   VARIABLE3, VARIABLE4);

Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-04 11:58:05 -07:00
Todd Poynor
2bf72399ca staging: gasket: sysfs: simplify comments for static functions
Static functions don't need kernel doc formatting, can be simplified.
Reformat comments that can be single-line.  Remove extraneous text.

Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-04 11:45:40 -07:00
Todd Poynor
c5505ad15c staging: gasket: sysfs: hold reference to device while in use
Hold a reference to the struct device while a gasket sysfs mapping
exists for the device and a pointer to the struct is kept in the mapping
data structures.

Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-04 11:40:10 -07:00
Todd Poynor
a7ac1d2090 staging: gasket: sysfs: remove unnecessary NULL check on device ptr
The device pointer passed into get_mapping() will never be NULL; the
check is unnecessary.

Reported-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-04 11:37:15 -07:00
Todd Poynor
84a0481115 staging: gasket: sysfs: remove check for refcount already zero
Remove the check for refcount already zero, which shouldn't be
necessary.

Change-Id: I0bc3966e21f8695f4787c2482dd5882dcd0f6dd9
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-04 11:36:01 -07:00
Todd Poynor
158ef348af staging: gasket: sysfs: convert to standard logging
Drop gasket logging calls in favor of standard logging.

Change-Id: Icd23c6c43b671cb8380b36bf26500bc835eec2c7
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-04 11:32:42 -07:00
Alex Van Damme
d737e80b17 Enable Apex on ARM64, fix compile issue
- Change from X86 only to X86 or ARM64 in Kconfig
- refcount_read doesn't exist in 4.11, so use atomic_read instead. This
is the same call that refcount_read in 4.12+ would make.

Change-Id: I48c97dd8c14136dcccaa8378b3a931a7872e1289
2018-07-23 16:11:14 -07:00
Todd Poynor
04f5568b57 staging: gasket: Remove stale pointers on error allocating attr array
If gasket_sysfs_create_mapping() hits errors allocating the attribute
array, remove stale pointers to device info from the mapping object.

Signed-off-by: Zhongze Hu <frankhu@chromium.org>
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-23 16:08:22 -07:00
Todd Poynor
a7546cc34c staging: gasket: Return EBUSY on mapping create when already in use
gasket_sysfs_create_mapping() return EBUSY if sysfs mapping already in
use, as a more appropriate error code than the current return of EINVAL,
which would indicate invalid parameters.

Signed-off-by: Zhongze Hu <frankhu@chromium.org>
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-23 16:08:21 -07:00
Greg Kroah-Hartman
1ba805dba8 staging: gasket: sysfs: remove legacy_device field
This field is only ever checked, never actually set, and looks to be
left-over from some old interface of some sort.  As it's not being used
at all here, and is just adding to the complexity, delete it.

Cc: Rob Springer <rspringer@google.com>
Cc: John Joseph <jnjoseph@google.com>
Cc: Ben Chan <benchan@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-23 16:08:21 -07:00
Greg Kroah-Hartman
1180baae6b staging: gasket: remove gasket_sysfs_register_show()
In an attempt to start to clean up the monstrosity of the sysfs abuse in
the gasket driver, let's remove code that is not used at all.  The
gasket_sysfs_register_show() function is never used, so delete it.

Cc: Rob Springer <rspringer@google.com>
Cc: John Joseph <jnjoseph@google.com>
Cc: Ben Chan <benchan@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-23 16:08:21 -07:00
Greg Kroah-Hartman
653a5901f5 staging: gasket: remove redundant license information
Now that the SPDX tag is in all gasket files, that identifies the
license in a specific and legally-defined manner.  So the extra GPL text
wording can be removed as it is no longer needed at all.

This is done on a quest to remove the 700+ different ways that files in
the kernel describe the GPL license text.  And there's unneeded stuff
like the address (sometimes incorrect) for the FSF which is never
needed.

Cc: Rob Springer <rspringer@google.com>
Cc: John Joseph <jnjoseph@google.com>
Cc: Ben Chan <benchan@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-23 16:08:20 -07:00
Greg Kroah-Hartman
8ff3da62cb staging: gasket: add SPDX identifiers to all files.
It's good to have SPDX identifiers in all files to make it easier to
audit the kernel tree for correct licenses.

Fix up the all of the staging gasket files to have a proper SPDX
identifier, based on the license text in the file itself.  The SPDX
identifier is a legally binding shorthand, which can be used instead of
the full boiler plate text.

Cc: Rob Springer <rspringer@google.com>
Cc: John Joseph <jnjoseph@google.com>
Cc: Ben Chan <benchan@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-23 16:08:20 -07:00
Todd Poynor
392480bf3f drivers/staging/gasket: Use refcount_read()
Use the refcount_read accessor function, avoid reaching into refcount
and atomic struct fields.

Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-23 16:08:20 -07:00
Kees Cook
e1c8e7a804 drivers/staging/gasket: Use 2-factor allocator calls
As already done treewide, switch from open-coded multiplication to using
2-factor allocator helpers.

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-23 16:08:19 -07:00
Simon Que
0305c1f77f drivers/staging: Gasket driver framework + Apex driver
The Gasket (Google ASIC Software, Kernel Extensions, and Tools) kernel
framework is a generic, flexible system that supports thin kernel
drivers. Gasket kernel drivers are expected to handle opening and
closing devices, mmap'ing BAR space as requested, a small selection of
ioctls, and handling page table translation (covered below). Any other
functions should be handled by userspace code.

The Gasket common module is not enough to run a device. In order to
customize the Gasket code for a given piece of hardware, a device
specific module must be created. At a minimum, this module must define a
struct gasket_driver_desc containing the device-specific data for use by
the framework; in addition, the module must declare an __init function
that calls gasket_register_device with the module's gasket_driver_desc
struct. Finally, the driver must define an exit function that calls
gasket_unregister_device with the module's gasket_driver_desc struct.

One of the core assumptions of the Gasket framework is that precisely
one process is allowed to have an open write handle to the device node
at any given time. (That process may, once it has one write handle, open
any number of additional write handles.) This is accomplished by
tracking open and close data for each driver instance.

Change-Id: I0ce1dc1dc9c533026adbc3aacaefb830ecdbc3e9
Signed-off-by: Rob Springer <rspringer@google.com>
Signed-off-by: John Joseph <jnjoseph@google.com>
Signed-off-by: Simon Que <sque@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-23 16:08:19 -07:00