mirror of
https://github.com/Fishwaldo/linux-bl808.git
synced 2025-06-17 20:25:19 +00:00
324b954ac8
Notify the user daemon that cookie is going to be withdrawn, providing a hint that the associated anonymous fd can be closed. Be noted that this is only a hint. The user daemon may close the associated anonymous fd when receiving the CLOSE request, then it will receive another anonymous fd when the cookie gets looked up. Or it may ignore the CLOSE request, and keep writing data through the anonymous fd. However the next time the cookie gets looked up, the user daemon will still receive another new anonymous fd. Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com> Acked-by: David Howells <dhowells@redhat.com> Link: https://lore.kernel.org/r/20220425122143.56815-5-jefflexu@linux.alibaba.com Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
51 lines
1.2 KiB
C
51 lines
1.2 KiB
C
/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
|
|
#ifndef _LINUX_CACHEFILES_H
|
|
#define _LINUX_CACHEFILES_H
|
|
|
|
#include <linux/types.h>
|
|
|
|
/*
|
|
* Fscache ensures that the maximum length of cookie key is 255. The volume key
|
|
* is controlled by netfs, and generally no bigger than 255.
|
|
*/
|
|
#define CACHEFILES_MSG_MAX_SIZE 1024
|
|
|
|
enum cachefiles_opcode {
|
|
CACHEFILES_OP_OPEN,
|
|
CACHEFILES_OP_CLOSE,
|
|
};
|
|
|
|
/*
|
|
* Message Header
|
|
*
|
|
* @msg_id a unique ID identifying this message
|
|
* @opcode message type, CACHEFILE_OP_*
|
|
* @len message length, including message header and following data
|
|
* @object_id a unique ID identifying a cache file
|
|
* @data message type specific payload
|
|
*/
|
|
struct cachefiles_msg {
|
|
__u32 msg_id;
|
|
__u32 opcode;
|
|
__u32 len;
|
|
__u32 object_id;
|
|
__u8 data[];
|
|
};
|
|
|
|
/*
|
|
* @data contains the volume_key followed directly by the cookie_key. volume_key
|
|
* is a NUL-terminated string; @volume_key_size indicates the size of the volume
|
|
* key in bytes. cookie_key is binary data, which is netfs specific;
|
|
* @cookie_key_size indicates the size of the cookie key in bytes.
|
|
*
|
|
* @fd identifies an anon_fd referring to the cache file.
|
|
*/
|
|
struct cachefiles_open {
|
|
__u32 volume_key_size;
|
|
__u32 cookie_key_size;
|
|
__u32 fd;
|
|
__u32 flags;
|
|
__u8 data[];
|
|
};
|
|
|
|
#endif
|