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#include <camellia/fsutil.h>
#include <kernel/arch/amd64/driver/util.h>
#include <kernel/mem/virt.h>
#include <kernel/panic.h>
#include <kernel/proc.h>
#include <kernel/vfs/request.h>
int req_readcopy(struct vfs_request *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);
virt_cpy_to(
req->caller->pages, req->output.buf,
buf + req->offset, req->output.len);
/* read errors are ignored. TODO write a spec */
return req->output.len;
}
void postqueue_join(struct vfs_request **queue, struct vfs_request *req) {
if (req->postqueue_next)
panic_invalid_state();
while (*queue)
queue = &(*queue)->postqueue_next;
*queue = req;
}
bool postqueue_pop(struct vfs_request **queue, void (*accept)(struct vfs_request *)) {
struct vfs_request *req = *queue;
if (req == NULL) return false;
*queue = req->postqueue_next;
accept(req);
return true;
}
void postqueue_ringreadall(struct vfs_request **queue, ring_t *r) {
struct vfs_request *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);
for (req = *queue; req; req = req->postqueue_next) {
size_t ret = min(mlen, req->output.len);
assert(req->type == VFSOP_READ);
if (req->caller)
virt_cpy_to(req->caller->pages, req->output.buf, tmp, ret);
vfsreq_finish_short(req, ret);
}
*queue = NULL;
}
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