On 2/7/25 01:13, Jason Gunthorpe wrote:
Each file descriptor gets a chunk of per-FD driver specific context that
allows the driver to attach a device specific struct to. The core code
takes care of the memory lifetime for this structure.
The ioctl dispatch and design is based on what was built for iommufd. The
ioctls have a struct which has a combined in/out behavior with a typical
'zero pad' scheme for future extension and backwards compatibility.
Like iommufd some shared logic does most of the ioctl marshalling and
compatibility work and tables diatches to some function pointers for
each unique iotcl.
This approach has proven to work quite well in the iommufd and rdma
subsystems.
Allocate an ioctl number space for the subsystem.
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxx>
diff --git a/drivers/fwctl/main.c b/drivers/fwctl/main.c
index 34946bdc3bf3d7..d561deaf2b86d8 100644
--- a/drivers/fwctl/main.c
+++ b/drivers/fwctl/main.c
@@ -10,6 +10,8 @@
#include <linux/module.h>
#include <linux/slab.h>
+#include <uapi/fwctl/fwctl.h>
+
enum {
FWCTL_MAX_DEVICES = 4096,
};
@@ -18,20 +20,128 @@ static_assert(FWCTL_MAX_DEVICES < (1U << MINORBITS));
static dev_t fwctl_dev;
static DEFINE_IDA(fwctl_ida);
+struct fwctl_ucmd {
+ struct fwctl_uctx *uctx;
+ void __user *ubuffer;
+ void *cmd;
+ u32 user_size;
+};
+
+/* On stack memory for the ioctl structs */
+union ucmd_buffer {
for most names you follow the usual prefixing rules, would be good
to do for all
