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
|
#include <camellia/fsutil.h>
#include <kernel/arch/amd64/driver/util.h>
#include <kernel/panic.h>
#include <kernel/proc.h>
#include <kernel/vfs/request.h>
int req_readcopy(VfsReq *req, const void *buf, size_t len) {
if (!req->caller) return -1;
assert(req->type == VFSOP_READ);
fs_normslice(&req->offset, &req->output.len, len, false);
/* read errors are ignored. TODO write a spec */
pcpy_to(req->caller, req->output.buf, buf + req->offset, req->output.len);
return req->output.len;
}
void postqueue_join(VfsReq **queue, VfsReq *req) {
if (req->postqueue_next)
panic_invalid_state();
while (*queue)
queue = &(*queue)->postqueue_next;
*queue = req;
}
bool postqueue_pop(VfsReq **queue, void (*accept)(VfsReq *)) {
VfsReq *req = *queue;
if (req == NULL) return false;
*queue = req->postqueue_next;
accept(req);
return true;
}
void postqueue_ringreadall(VfsReq **queue, ring_t *r) {
VfsReq *req;
char tmp[64];
size_t mlen = 0;
if (ring_used(r) == 0) return;
/* read as much as the biggest request wants */
for (req = *queue; req; req = req->postqueue_next)
mlen = max(mlen, req->output.len);
mlen = min(mlen, sizeof tmp);
mlen = ring_get(r, tmp, mlen);
while (*queue) {
req = *queue;
*queue = req->postqueue_next;
size_t ret = min(mlen, req->output.len);
assert(req->type == VFSOP_READ);
if (req->caller) {
pcpy_to(req->caller, req->output.buf, tmp, ret);
}
vfsreq_finish_short(req, ret);
}
}
size_t ring_to_virt(ring_t *r, Proc *proc, void __user *ubuf, size_t max) {
char tmp[32];
if (max > sizeof tmp) max = sizeof tmp;
max = ring_get(r, tmp, max);
return pcpy_to(proc, ubuf, tmp, max);
}
|
