*/
void fuse_reset_request(struct fuse_req *req)
{
- int preallocated = req->preallocated;
BUG_ON(atomic_read(&req->count) != 1);
fuse_request_init(req);
- req->preallocated = preallocated;
}
static void __fuse_get_request(struct fuse_req *req)
atomic_dec(&req->count);
}
-static struct fuse_req *do_get_request(struct fuse_conn *fc)
+struct fuse_req *fuse_get_req(struct fuse_conn *fc)
{
struct fuse_req *req;
-
- spin_lock(&fc->lock);
- BUG_ON(list_empty(&fc->unused_list));
- req = list_entry(fc->unused_list.next, struct fuse_req, list);
- list_del_init(&req->list);
- spin_unlock(&fc->lock);
- fuse_request_init(req);
- req->preallocated = 1;
- req->in.h.uid = current->fsuid;
- req->in.h.gid = current->fsgid;
- req->in.h.pid = current->pid;
- return req;
-}
-
-/* This can return NULL, but only in case it's interrupted by a SIGKILL */
-struct fuse_req *fuse_get_request(struct fuse_conn *fc)
-{
- int intr;
sigset_t oldset;
+ int intr;
+ int err;
atomic_inc(&fc->num_waiting);
block_sigs(&oldset);
- intr = down_interruptible(&fc->outstanding_sem);
+ intr = wait_event_interruptible(fc->blocked_waitq, !fc->blocked);
restore_sigs(&oldset);
- if (intr) {
- atomic_dec(&fc->num_waiting);
- return NULL;
- }
- return do_get_request(fc);
-}
+ err = -EINTR;
+ if (intr)
+ goto out;
-/* Must be called with fc->lock held */
-static void fuse_putback_request(struct fuse_conn *fc, struct fuse_req *req)
-{
- if (req->preallocated) {
- atomic_dec(&fc->num_waiting);
- list_add(&req->list, &fc->unused_list);
- } else
- fuse_request_free(req);
+ req = fuse_request_alloc();
+ err = -ENOMEM;
+ if (!req)
+ goto out;
- /* If we are in debt decrease that first */
- if (fc->outstanding_debt)
- fc->outstanding_debt--;
- else
- up(&fc->outstanding_sem);
+ req->in.h.uid = current->fsuid;
+ req->in.h.gid = current->fsgid;
+ req->in.h.pid = current->pid;
+ req->waiting = 1;
+ return req;
+
+ out:
+ atomic_dec(&fc->num_waiting);
+ return ERR_PTR(err);
}
void fuse_put_request(struct fuse_conn *fc, struct fuse_req *req)
{
if (atomic_dec_and_test(&req->count)) {
- spin_lock(&fc->lock);
- fuse_putback_request(fc, req);
- spin_unlock(&fc->lock);
+ if (req->waiting)
+ atomic_dec(&fc->num_waiting);
+ fuse_request_free(req);
}
}
-static void fuse_put_request_locked(struct fuse_conn *fc, struct fuse_req *req)
-{
- if (atomic_dec_and_test(&req->count))
- fuse_putback_request(fc, req);
-}
-
+/*
+ * Called with sbput_sem held for read (request_end) or write
+ * (fuse_put_super). By the time fuse_put_super() is finished, all
+ * inodes belonging to background requests must be released, so the
+ * iputs have to be done within the locked region.
+ */
void fuse_release_background(struct fuse_conn *fc, struct fuse_req *req)
{
iput(req->inode);
iput(req->inode2);
- if (req->file)
- fput(req->file);
spin_lock(&fc->lock);
list_del(&req->bg_entry);
+ if (fc->num_background == FUSE_MAX_BACKGROUND) {
+ fc->blocked = 0;
+ wake_up_all(&fc->blocked_waitq);
+ }
+ fc->num_background--;
spin_unlock(&fc->lock);
}
list_del(&req->list);
req->state = FUSE_REQ_FINISHED;
if (!req->background) {
- wake_up(&req->waitq);
- fuse_put_request_locked(fc, req);
spin_unlock(&fc->lock);
+ wake_up(&req->waitq);
+ fuse_put_request(fc, req);
} else {
void (*end) (struct fuse_conn *, struct fuse_req *) = req->end;
req->end = NULL;
if (fc->mounted)
fuse_release_background(fc, req);
up_read(&fc->sbput_sem);
+
+ /* fput must go outside sbput_sem, otherwise it can deadlock */
+ if (req->file)
+ fput(req->file);
+
if (end)
end(fc, req);
else
{
req->background = 1;
list_add(&req->bg_entry, &fc->background);
+ fc->num_background++;
+ if (fc->num_background == FUSE_MAX_BACKGROUND)
+ fc->blocked = 1;
if (req->inode)
req->inode = igrab(req->inode);
if (req->inode2)
req->in.h.unique = fc->reqctr;
req->in.h.len = sizeof(struct fuse_in_header) +
len_args(req->in.numargs, (struct fuse_arg *) req->in.args);
- if (!req->preallocated) {
- /* If request is not preallocated (either FORGET or
- RELEASE), then still decrease outstanding_sem, so
- user can't open infinite number of files while not
- processing the RELEASE requests. However for
- efficiency do it without blocking, so if down()
- would block, just increase the debt instead */
- if (down_trylock(&fc->outstanding_sem))
- fc->outstanding_debt++;
- }
list_add_tail(&req->list, &fc->pending);
req->state = FUSE_REQ_PENDING;
+ if (!req->waiting) {
+ req->waiting = 1;
+ atomic_inc(&fc->num_waiting);
+ }
wake_up(&fc->waitq);
kill_fasync(&fc->fasync, SIGIO, POLL_IN);
}
static void request_send_nowait(struct fuse_conn *fc, struct fuse_req *req)
{
spin_lock(&fc->lock);
+ background_request(fc, req);
if (fc->connected) {
queue_request(fc, req);
spin_unlock(&fc->lock);
void request_send_background(struct fuse_conn *fc, struct fuse_req *req)
{
req->isreply = 1;
- spin_lock(&fc->lock);
- background_request(fc, req);
- spin_unlock(&fc->lock);
request_send_nowait(fc, req);
}