diff options
Diffstat (limited to 'kernel/liveupdate/luo_internal.h')
| -rw-r--r-- | kernel/liveupdate/luo_internal.h | 110 |
1 files changed, 110 insertions, 0 deletions
diff --git a/kernel/liveupdate/luo_internal.h b/kernel/liveupdate/luo_internal.h new file mode 100644 index 000000000000..c8973b543d1d --- /dev/null +++ b/kernel/liveupdate/luo_internal.h @@ -0,0 +1,110 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +/* + * Copyright (c) 2025, Google LLC. + * Pasha Tatashin <pasha.tatashin@soleen.com> + */ + +#ifndef _LINUX_LUO_INTERNAL_H +#define _LINUX_LUO_INTERNAL_H + +#include <linux/liveupdate.h> +#include <linux/uaccess.h> + +struct luo_ucmd { + void __user *ubuffer; + u32 user_size; + void *cmd; +}; + +static inline int luo_ucmd_respond(struct luo_ucmd *ucmd, + size_t kernel_cmd_size) +{ + /* + * Copy the minimum of what the user provided and what we actually + * have. + */ + if (copy_to_user(ucmd->ubuffer, ucmd->cmd, + min_t(size_t, ucmd->user_size, kernel_cmd_size))) { + return -EFAULT; + } + return 0; +} + +/* + * Handles a deserialization failure: devices and memory is in unpredictable + * state. + * + * Continuing the boot process after a failure is dangerous because it could + * lead to leaks of private data. + */ +#define luo_restore_fail(__fmt, ...) panic(__fmt, ##__VA_ARGS__) + +/* Mimics list_for_each_entry() but for private list head entries */ +#define luo_list_for_each_private(pos, head, member) \ + for (struct list_head *__iter = (head)->next; \ + __iter != (head) && \ + ({ pos = container_of(__iter, typeof(*(pos)), member); 1; }); \ + __iter = __iter->next) + +/** + * struct luo_file_set - A set of files that belong to the same sessions. + * @files_list: An ordered list of files associated with this session, it is + * ordered by preservation time. + * @files: The physically contiguous memory block that holds the serialized + * state of files. + * @count: A counter tracking the number of files currently stored in the + * @files_list for this session. + */ +struct luo_file_set { + struct list_head files_list; + struct luo_file_ser *files; + long count; +}; + +/** + * struct luo_session - Represents an active or incoming Live Update session. + * @name: A unique name for this session, used for identification and + * retrieval. + * @ser: Pointer to the serialized data for this session. + * @list: A list_head member used to link this session into a global list + * of either outgoing (to be preserved) or incoming (restored from + * previous kernel) sessions. + * @retrieved: A boolean flag indicating whether this session has been + * retrieved by a consumer in the new kernel. + * @file_set: A set of files that belong to this session. + * @mutex: protects fields in the luo_session. + */ +struct luo_session { + char name[LIVEUPDATE_SESSION_NAME_LENGTH]; + struct luo_session_ser *ser; + struct list_head list; + bool retrieved; + struct luo_file_set file_set; + struct mutex mutex; +}; + +int luo_session_create(const char *name, struct file **filep); +int luo_session_retrieve(const char *name, struct file **filep); +int __init luo_session_setup_outgoing(void *fdt); +int __init luo_session_setup_incoming(void *fdt); +int luo_session_serialize(void); +int luo_session_deserialize(void); +bool luo_session_quiesce(void); +void luo_session_resume(void); + +int luo_preserve_file(struct luo_file_set *file_set, u64 token, int fd); +void luo_file_unpreserve_files(struct luo_file_set *file_set); +int luo_file_freeze(struct luo_file_set *file_set, + struct luo_file_set_ser *file_set_ser); +void luo_file_unfreeze(struct luo_file_set *file_set, + struct luo_file_set_ser *file_set_ser); +int luo_retrieve_file(struct luo_file_set *file_set, u64 token, + struct file **filep); +int luo_file_finish(struct luo_file_set *file_set); +int luo_file_deserialize(struct luo_file_set *file_set, + struct luo_file_set_ser *file_set_ser); +void luo_file_set_init(struct luo_file_set *file_set); +void luo_file_set_destroy(struct luo_file_set *file_set); + +#endif /* _LINUX_LUO_INTERNAL_H */ |