papr-rtas-common.h

 1/* SPDX-License-Identifier: GPL-2.0-only */
 2#ifndef _ASM_POWERPC_PAPR_RTAS_COMMON_H
 3#define _ASM_POWERPC_PAPR_RTAS_COMMON_H
 4
 5#include <linux/types.h>
 6
 7/*
 8 * Return codes for sequence based RTAS calls.
 9 * Not listed under PAPR+ v2.13 7.2.8: "Return Codes".
10 * But defined in the specific section of each RTAS call.
11 */
12#define RTAS_SEQ_COMPLETE	0 /* All data has been retrieved. */
13#define RTAS_SEQ_MORE_DATA	1 /* More data is available */
14#define RTAS_SEQ_START_OVER	-4 /* Data changed, restart call sequence. */
15
16/*
17 * Internal "blob" APIs for accumulating RTAS call results into
18 * an immutable buffer to be attached to a file descriptor.
19 */
20struct papr_rtas_blob {
21	const char *data;
22	size_t len;
23};
24
25/**
26 * struct papr_sequence - State for managing a sequence of RTAS calls.
27 * @error:  Shall be zero as long as the sequence has not encountered an error,
28 *          -ve errno otherwise. Use papr_rtas_sequence_set_err() to update.
29 * @params: Parameter block to pass to rtas_*() calls.
30 * @begin: Work area allocation and initialize the needed parameter
31 *         values passed to RTAS call
32 * @end: Free the allocated work area
33 * @work: Obtain data with RTAS call and invoke it until the sequence is
34 *        completed.
35 *
36 */
37struct papr_rtas_sequence {
38	int error;
39	void *params;
40	void (*begin)(struct papr_rtas_sequence *seq);
41	void (*end)(struct papr_rtas_sequence *seq);
42	const char *(*work)(struct papr_rtas_sequence *seq, size_t *len);
43};
44
45extern bool papr_rtas_blob_has_data(const struct papr_rtas_blob *blob);
46extern void papr_rtas_blob_free(const struct papr_rtas_blob *blob);
47extern int papr_rtas_sequence_set_err(struct papr_rtas_sequence *seq,
48		int err);
49extern const struct papr_rtas_blob *papr_rtas_retrieve(struct papr_rtas_sequence *seq);
50extern long papr_rtas_setup_file_interface(struct papr_rtas_sequence *seq,
51			const struct file_operations *fops, char *name);
52extern bool papr_rtas_sequence_should_stop(const struct papr_rtas_sequence *seq,
53				s32 status, bool init_state);
54extern ssize_t papr_rtas_common_handle_read(struct file *file,
55			char __user *buf, size_t size, loff_t *off);
56extern int papr_rtas_common_handle_release(struct inode *inode,
57					struct file *file);
58extern loff_t papr_rtas_common_handle_seek(struct file *file, loff_t off,
59					int whence);
60#endif /* _ASM_POWERPC_PAPR_RTAS_COMMON_H */
61