1 /* SPDX-License-Identifier: GPL-2.0 */ 2 3 /* 4 * Copyright (c) 2025, Google LLC. 5 * Pasha Tatashin <pasha.tatashin@soleen.com> 6 */ 7 8 #ifndef _LINUX_LUO_INTERNAL_H 9 #define _LINUX_LUO_INTERNAL_H 10 11 #include <linux/liveupdate.h> 12 #include <linux/uaccess.h> 13 #include <linux/kho_block.h> 14 15 struct luo_ucmd { 16 void __user *ubuffer; 17 u32 user_size; 18 void *cmd; 19 }; 20 21 static inline int luo_ucmd_respond(struct luo_ucmd *ucmd, 22 size_t kernel_cmd_size) 23 { 24 /* 25 * Copy the minimum of what the user provided and what we actually 26 * have. 27 */ 28 if (copy_to_user(ucmd->ubuffer, ucmd->cmd, 29 min_t(size_t, ucmd->user_size, kernel_cmd_size))) { 30 return -EFAULT; 31 } 32 return 0; 33 } 34 35 /* 36 * Handles a deserialization failure: devices and memory is in unpredictable 37 * state. 38 * 39 * Continuing the boot process after a failure is dangerous because it could 40 * lead to leaks of private data. 41 */ 42 #define luo_restore_fail(__fmt, ...) panic(__fmt, ##__VA_ARGS__) 43 44 /** 45 * struct luo_file_set - A set of files that belong to the same sessions. 46 * @files_list: An ordered list of files associated with this session, it is 47 * ordered by preservation time. 48 * @block_set: The set of serialization blocks. 49 * @count: A counter tracking the number of files currently stored in the 50 * @files_list for this session. 51 */ 52 struct luo_file_set { 53 struct list_head files_list; 54 struct kho_block_set block_set; 55 u64 count; 56 }; 57 58 /** 59 * struct luo_session - Represents an active or incoming Live Update session. 60 * @name: A unique name for this session, used for identification and 61 * retrieval. 62 * @list: A list_head member used to link this session into a global list 63 * of either outgoing (to be preserved) or incoming (restored from 64 * previous kernel) sessions. 65 * @retrieved: A boolean flag indicating whether this session has been 66 * retrieved by a consumer in the new kernel. 67 * @file_set: A set of files that belong to this session. 68 * @mutex: protects fields in the luo_session. 69 */ 70 struct luo_session { 71 char name[LIVEUPDATE_SESSION_NAME_LENGTH]; 72 struct list_head list; 73 bool retrieved; 74 struct luo_file_set file_set; 75 struct mutex mutex; 76 }; 77 78 extern struct rw_semaphore luo_register_rwlock; 79 80 int luo_session_create(const char *name, struct file **filep); 81 int luo_session_retrieve(const char *name, struct file **filep); 82 void __init luo_session_setup_outgoing(u64 *sessions_pa); 83 int __init luo_session_setup_incoming(u64 sessions_pa); 84 int luo_session_serialize(void); 85 int luo_session_deserialize(void); 86 87 int luo_preserve_file(struct luo_file_set *file_set, u64 token, int fd); 88 void luo_file_unpreserve_files(struct luo_file_set *file_set); 89 int luo_file_freeze(struct luo_file_set *file_set, 90 struct luo_file_set_ser *file_set_ser); 91 void luo_file_unfreeze(struct luo_file_set *file_set, 92 struct luo_file_set_ser *file_set_ser); 93 int luo_retrieve_file(struct luo_file_set *file_set, u64 token, 94 struct file **filep); 95 int luo_file_finish(struct luo_file_set *file_set); 96 int luo_file_deserialize(struct luo_file_set *file_set, 97 struct luo_file_set_ser *file_set_ser); 98 void luo_file_set_init(struct luo_file_set *file_set); 99 void luo_file_set_destroy(struct luo_file_set *file_set); 100 101 int luo_flb_file_preserve(struct liveupdate_file_handler *fh); 102 void luo_flb_file_unpreserve(struct liveupdate_file_handler *fh); 103 void luo_flb_file_finish(struct liveupdate_file_handler *fh); 104 void luo_flb_unregister_all(struct liveupdate_file_handler *fh); 105 int __init luo_flb_setup_outgoing(u64 *flbs_pa); 106 void __init luo_flb_setup_incoming(u64 flbs_pa); 107 void luo_flb_serialize(void); 108 109 #ifdef CONFIG_LIVEUPDATE_TEST 110 void liveupdate_test_register(struct liveupdate_file_handler *fh); 111 #else 112 static inline void liveupdate_test_register(struct liveupdate_file_handler *fh) { } 113 #endif 114 115 #endif /* _LINUX_LUO_INTERNAL_H */ 116