[ Upstream commit b7c0e1ecee403a43abc89eb3e75672b01ff2ece9 ]
The current implementation of the fpga region assumes that the low-level
module registers a driver for the parent device and uses its owner pointer
to take the module's refcount. This approach is problematic since it can
lead to a null pointer dereference while attempting to get the region
during programming if the parent device does not have a driver.
To address this problem, add a module owner pointer to the fpga_region
struct and use it to take the module's refcount. Modify the functions for
registering a region to take an additional owner module parameter and
rename them to avoid conflicts. Use the old function names for helper
macros that automatically set the module that registers the region as the
owner. This ensures compatibility with existing low-level control modules
and reduces the chances of registering a region without setting the owner.
Also, update the documentation to keep it consistent with the new interface
for registering an fpga region.
Fixes: 0fa20cdfcc1f ("fpga: fpga-region: device tree control for FPGA")
Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Suggested-by: Xu Yilun <yilun.xu@intel.com>
Reviewed-by: Russ Weight <russ.weight@linux.dev>
Signed-off-by: Marco Pagani <marpagan@redhat.com>
Acked-by: Xu Yilun <yilun.xu@intel.com>
Link: https://lore.kernel.org/r/20240419083601.77403-1-marpagan@redhat.com
Signed-off-by: Xu Yilun <yilun.xu@linux.intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 8886a579744fbfa53e69aa453ed10ae3b1f9abac ]
The FPGA region class driver data structure is being treated as a
managed resource instead of using the standard dev_release call-back
function to release the class data structure. This change removes the
managed resource code and combines the create() and register()
functions into a single register() or register_full() function.
The register_full() function accepts an info data structure to provide
flexibility in passing optional parameters. The register() function
supports the current parameter list for users that don't require the
use of optional parameters.
Signed-off-by: Russ Weight <russell.h.weight@intel.com>
Reviewed-by: Xu Yilun <yilun.xu@intel.com>
Acked-by: Xu Yilun <yilun.xu@intel.com>
Signed-off-by: Moritz Fischer <mdf@kernel.org>
Stable-dep-of: b7c0e1ecee40 ("fpga: region: add owner module and take its refcount")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 011c49e3703854e52c0fb88f22cf38aca1d4d514 ]
Change use of 'a fpga' to 'an fpga'
Signed-off-by: Tom Rix <trix@redhat.com>
Link: https://lore.kernel.org/r/20210608212350.3029742-10-trix@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Stable-dep-of: b7c0e1ecee40 ("fpga: region: add owner module and take its refcount")
Signed-off-by: Sasha Levin <sashal@kernel.org>
