struct fuse_req *fuse_get_req(struct fuse_conn *fc)
{
struct fuse_req *req;
sigset_t oldset;
int intr;
int err;
atomic_inc(&fc->num_waiting);
block_sigs(&oldset);
intr = wait_event_interruptible(fc->blocked_waitq, !fc->blocked);
restore_sigs(&oldset);
err = -EINTR;
if (intr)
goto out;
err = -ENOTCONN;
if (!fc->connected)
goto out;
req = fuse_request_alloc();
err = -ENOMEM;
if (!req)
goto out;
fuse_req_init_context(req);
req->waiting = 1;
return req;
out:
atomic_dec(&fc->num_waiting);
return ERR_PTR(err);
}
struct gfskdev_req *
gfskdev_get_req(struct gfskdev_conn *dc)
{
struct gfskdev_req *req;
sigset_t oldset;
int intr;
int err;
atomic_inc(&dc->num_waiting);
block_sigs(&oldset);
intr = wait_event_interruptible(dc->blocked_waitq, !dc->blocked);
restore_sigs(&oldset);
err = -EINTR;
if (intr)
goto out;
err = -ENOTCONN;
if (!dc->connected)
goto out;
req = gfskdev_request_alloc();
err = -ENOMEM;
if (!req)
goto out;
gfskdev_req_init_context(req);
req->waiting = 1;
return (req);
out:
atomic_dec(&dc->num_waiting);
return (ERR_PTR(err));
}
/*
* eval - Evaluate the command line that the user has just typed in
*
* If the user has requested a built-in command (quit, jobs, bg or fg)
* then execute it immediately. Otherwise, fork a child process and
* run the job in the context of the child. If the job is running in
* the foreground, wait for it to terminate and then return. Note:
* each child process must have a unique process group ID so that our
* background children don't receive SIGINT (SIGTSTP) from the kernel
* when we type ctrl-c (ctrl-z) at the keyboard.
*/
void
eval(char *cmdline)
{
int bg; /* should the job run in bg or fg? */
struct cmdline_tokens tok;
/* Parse command line */
bg = parseline(cmdline, &tok);
if (bg == -1) return; /* parsing error */
if (tok.argv[0] == NULL) return; /* ignore empty lines */
if(!check_builtin_cmds(&tok)){
sigset_t newset,oldset;
block_sigs(&newset, &oldset);
pid_t pid = fork();
if(pid < 0){
unix_error("error in fork child process");
}
if(pid == 0){
handle_child_process(&tok, bg, pid, &oldset);
} else {
handle_parent_process(&tok, bg, pid, &oldset, cmdline);
}
}
return;
}
/* Called with fc->lock held. Releases, and then reacquires it. */
static void request_wait_answer(struct fuse_conn *fc, struct fuse_req *req)
{
if (!fc->no_interrupt) {
/* Any signal may interrupt this */
wait_answer_interruptible(fc, req);
if (req->aborted)
goto aborted;
if (req->state == FUSE_REQ_FINISHED)
return;
req->interrupted = 1;
if (req->state == FUSE_REQ_SENT)
queue_interrupt(fc, req);
}
if (req->force) {
spin_unlock(&fc->lock);
wait_event(req->waitq, req->state == FUSE_REQ_FINISHED);
spin_lock(&fc->lock);
} else {
sigset_t oldset;
/* Only fatal signals may interrupt this */
block_sigs(&oldset);
wait_answer_interruptible(fc, req);
restore_sigs(&oldset);
}
if (req->aborted)
goto aborted;
if (req->state == FUSE_REQ_FINISHED)
return;
req->out.h.error = -EINTR;
req->aborted = 1;
aborted:
if (req->locked) {
/* This is uninterruptible sleep, because data is
being copied to/from the buffers of req. During
locked state, there mustn't be any filesystem
operation (e.g. page fault), since that could lead
to deadlock */
spin_unlock(&fc->lock);
wait_event(req->waitq, !req->locked);
spin_lock(&fc->lock);
}
if (req->state == FUSE_REQ_PENDING) {
list_del(&req->list);
__fuse_put_request(req);
} else if (req->state == FUSE_REQ_SENT) {
spin_unlock(&fc->lock);
wait_event(req->waitq, req->state == FUSE_REQ_FINISHED);
spin_lock(&fc->lock);
}
}
static struct fuse_req *__fuse_get_req(struct fuse_conn *fc, unsigned npages,
bool for_background)
{
struct fuse_req *req;
int err;
atomic_inc(&fc->num_waiting);
if (fuse_block_alloc(fc, for_background)) {
sigset_t oldset;
int intr;
block_sigs(&oldset);
intr = wait_event_interruptible_exclusive(fc->blocked_waitq,
!fuse_block_alloc(fc, for_background));
restore_sigs(&oldset);
err = -EINTR;
if (intr)
goto out;
}
err = -ENOTCONN;
if (!fc->connected)
goto out;
req = fuse_request_alloc(npages);
err = -ENOMEM;
if (!req) {
if (for_background)
wake_up(&fc->blocked_waitq);
goto out;
}
fuse_req_init_context(req);
req->waiting = 1;
req->background = for_background;
return req;
out:
atomic_dec(&fc->num_waiting);
return ERR_PTR(err);
}
