blob: 9ffc9c28544fe811b7f835d2552a2231a4fa283b (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
|
#ifndef __LIB_FS_BACKEND__
#define __LIB_FS_BACKEND__
#include <aio.h>
#include <xs.h>
#include <xen/grant_table.h>
#include <xen/event_channel.h>
#include <xen/io/ring.h>
#include <xen/io/fsif.h>
#include "sys-queue.h"
#define ROOT_NODE "backend/vfs"
#define EXPORTS_SUBNODE "exports"
#define EXPORTS_NODE ROOT_NODE"/"EXPORTS_SUBNODE
#define WATCH_NODE EXPORTS_NODE"/requests"
#define MAX_FDS 16
#define MAX_RING_SIZE 16
struct fs_export
{
int export_id;
char *export_path;
char *name;
struct fs_export *next;
};
struct fs_request
{
struct fs_mount *mount;
int id;
int active;
void *page; /* Pointer to mapped grant */
int count;
struct fsif_request req_shadow;
struct aiocb aiocb;
};
struct fs_mount
{
struct fs_export *export;
int dom_id;
char *frontend;
int mount_id; /* = backend id */
grant_ref_t grefs[MAX_RING_SIZE];
evtchn_port_t remote_evtchn;
xc_interface *xch; /* just for error logging, so a dummy */
int evth; /* Handle to the event channel */
evtchn_port_t local_evtchn;
int gnth;
int shared_ring_size; /* in pages */
struct fsif_back_ring ring;
int nr_entries;
struct fs_request *requests;
unsigned short *freelist;
int fds[MAX_FDS];
LIST_ENTRY(fs_mount) entries;
};
void terminate_mount_request(struct fs_mount *mount);
/* Handle to XenStore driver */
extern struct xs_handle *xsh;
bool xenbus_create_request_node(void);
int xenbus_register_export(struct fs_export *export);
int xenbus_get_watch_fd(void);
int xenbus_read_mount_request(struct fs_mount *mount, char *frontend);
bool xenbus_write_backend_node(struct fs_mount *mount);
bool xenbus_write_backend_state(struct fs_mount *mount, const char *state);
void xenbus_free_backend_node(struct fs_mount *mount);
int xenbus_frontend_state_changed(struct fs_mount *mount, const char *oldstate);
bool xenbus_watch_frontend_state(struct fs_mount *mount);
bool xenbus_unwatch_frontend_state(struct fs_mount *mount);
char* xenbus_read_frontend_state(struct fs_mount *mount);
/* File operations, implemented in fs-ops.c */
struct fs_op
{
int type; /* Type of request (from fsif.h) this handlers
are responsible for */
void (*dispatch_handler)(struct fs_mount *mount, struct fsif_request *req);
void (*response_handler)(struct fs_mount *mount, struct fs_request *req);
};
/* This NULL terminated array of all file requests handlers */
extern struct fs_op *fsops[];
static inline void add_id_to_freelist(unsigned int id,unsigned short* freelist)
{
freelist[id + 1] = freelist[0];
freelist[0] = id;
}
static inline unsigned short get_id_from_freelist(unsigned short* freelist)
{
unsigned int id = freelist[0];
freelist[0] = freelist[id + 1];
return id;
}
#endif /* __LIB_FS_BACKEND__ */
|
