include/linux/pstore.h

1 /* SPDX-License-Identifier: GPL-2.0-only */
3  * Persistent Storage - pstore.h
24  * pstore record types (see fs/pstore/platform.c for pstore_type_names[])
35 	/* PPC64-specific partition types */
51  * struct pstore_record - details of a pstore record entry
53  * @type:	pstore record type
54  * @id:		per-type unique identifier for record
55  * @time:	timestamp of the record
56  * @buf:	pointer to record contents
57  * @size:	size of @buf
61  *		kfree()d by the pstore core if non-NULL
62  *		when the record is freed.
68  * @part:	position in a multipart record
78 	ssize_t			size;  member
89  * struct pstore_info - backend pstore driver structure
96  * @bufsize:	size of @buf available for crash dump bytes (must match
109  * @data:	backend-private pointer passed back during callbacks
119  *	Returns 0 on success, and non-zero on error.
128  *	Returns 0 on success, and non-zero on error. (Though pstore will
132  *	Read next available backend record. Called after a successful
135  *	@record:
136  *		pointer to record to populate. @buf should be allocated
141  *	Returns record size on success, zero when no more records are
145  *	A newly generated record needs to be written to backend storage.
147  *	@record:
148  *		pointer to record metadata. When @type is PSTORE_TYPE_DMESG,
153  *		can help identify this record to a future @erase callback.
155  *		when available. The @size field will have the size of data
158  *	Returns 0 on success, and non-zero on error.
161  *	Perform a frontend write to a backend record, using a specified
163  *	@record @buf.
165  *	@record:	pointer to record metadata.
168  *	Returns 0 on success, and non-zero on error.
171  *	Delete a record from backend storage.  Different backends
172  *	identify records differently, so entire original record is
176  *	@record:	pointer to record metadata.
178  *	Returns 0 on success, and non-zero on error.
197 	ssize_t		(*read)(struct pstore_record *record);
198 	int		(*write)(struct pstore_record *record);
199 	int		(*write_user)(struct pstore_record *record,
201 	int		(*erase)(struct pstore_record *record);
231 #define TS_CPU_MASK (BIT(TS_CPU_SHIFT) - 1)
242 	rec->ip |= cpu;  in pstore_ftrace_encode_cpu()
248 	return rec->ip & PSTORE_CPU_IN_IP;  in pstore_ftrace_decode_cpu()
254 	return rec->ts;  in pstore_ftrace_read_timestamp()
260 	rec->ts = val;  in pstore_ftrace_write_timestamp()
266 	rec->ts &= ~(TS_CPU_MASK);  in pstore_ftrace_encode_cpu()
267 	rec->ts |= cpu;  in pstore_ftrace_encode_cpu()
273 	return rec->ts & TS_CPU_MASK;  in pstore_ftrace_decode_cpu()
279 	return rec->ts >> TS_CPU_SHIFT;  in pstore_ftrace_read_timestamp()
285 	rec->ts = (rec->ts & TS_CPU_MASK) | (val << TS_CPU_SHIFT);  in pstore_ftrace_write_timestamp()