diff options
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/fwctl.h | 46 | ||||
| -rw-r--r-- | include/uapi/fwctl/fwctl.h | 38 |
2 files changed, 84 insertions, 0 deletions
diff --git a/include/linux/fwctl.h b/include/linux/fwctl.h index 39d5059c9e59..faa4b2c780e0 100644 --- a/include/linux/fwctl.h +++ b/include/linux/fwctl.h @@ -11,7 +11,30 @@ struct fwctl_device; struct fwctl_uctx; +/** + * struct fwctl_ops - Driver provided operations + * + * fwctl_unregister() will wait until all excuting ops are completed before it + * returns. Drivers should be mindful to not let their ops run for too long as + * it will block device hot unplug and module unloading. + */ struct fwctl_ops { + /** + * @uctx_size: The size of the fwctl_uctx struct to allocate. The first + * bytes of this memory will be a fwctl_uctx. The driver can use the + * remaining bytes as its private memory. + */ + size_t uctx_size; + /** + * @open_uctx: Called when a file descriptor is opened before the uctx + * is ever used. + */ + int (*open_uctx)(struct fwctl_uctx *uctx); + /** + * @close_uctx: Called when the uctx is destroyed, usually when the FD + * is closed. + */ + void (*close_uctx)(struct fwctl_uctx *uctx); }; /** @@ -26,6 +49,15 @@ struct fwctl_device { struct device dev; /* private: */ struct cdev cdev; + + /* Protect uctx_list */ + struct mutex uctx_list_lock; + struct list_head uctx_list; + /* + * Protect ops, held for write when ops becomes NULL during unregister, + * held for read whenever ops is loaded or an ops function is running. + */ + struct rw_semaphore registration_lock; const struct fwctl_ops *ops; }; @@ -66,4 +98,18 @@ DEFINE_FREE(fwctl, struct fwctl_device *, if (_T) fwctl_put(_T)); int fwctl_register(struct fwctl_device *fwctl); void fwctl_unregister(struct fwctl_device *fwctl); +/** + * struct fwctl_uctx - Per user FD context + * @fwctl: fwctl instance that owns the context + * + * Every FD opened by userspace will get a unique context allocation. Any driver + * private data will follow immediately after. + */ +struct fwctl_uctx { + struct fwctl_device *fwctl; + /* private: */ + /* Head at fwctl_device::uctx_list */ + struct list_head uctx_list_entry; +}; + #endif diff --git a/include/uapi/fwctl/fwctl.h b/include/uapi/fwctl/fwctl.h new file mode 100644 index 000000000000..8f5fe821cf28 --- /dev/null +++ b/include/uapi/fwctl/fwctl.h @@ -0,0 +1,38 @@ +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ +/* Copyright (c) 2024-2025, NVIDIA CORPORATION & AFFILIATES. + */ +#ifndef _UAPI_FWCTL_H +#define _UAPI_FWCTL_H + +#define FWCTL_TYPE 0x9A + +/** + * DOC: General ioctl format + * + * The ioctl interface follows a general format to allow for extensibility. Each + * ioctl is passed a structure pointer as the argument providing the size of + * the structure in the first u32. The kernel checks that any structure space + * beyond what it understands is 0. This allows userspace to use the backward + * compatible portion while consistently using the newer, larger, structures. + * + * ioctls use a standard meaning for common errnos: + * + * - ENOTTY: The IOCTL number itself is not supported at all + * - E2BIG: The IOCTL number is supported, but the provided structure has + * non-zero in a part the kernel does not understand. + * - EOPNOTSUPP: The IOCTL number is supported, and the structure is + * understood, however a known field has a value the kernel does not + * understand or support. + * - EINVAL: Everything about the IOCTL was understood, but a field is not + * correct. + * - ENOMEM: Out of memory. + * - ENODEV: The underlying device has been hot-unplugged and the FD is + * orphaned. + * + * As well as additional errnos, within specific ioctls. + */ +enum { + FWCTL_CMD_BASE = 0, +}; + +#endif |