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Diffstat (limited to 'fs/fuse/dev.c')
-rw-r--r--fs/fuse/dev.c80
1 files changed, 63 insertions, 17 deletions
diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c
index 9bfd1a3214e6..a6c1664e330b 100644
--- a/fs/fuse/dev.c
+++ b/fs/fuse/dev.c
@@ -111,7 +111,7 @@ static void restore_sigs(sigset_t *oldset)
sigprocmask(SIG_SETMASK, oldset, NULL);
}
-static void __fuse_get_request(struct fuse_req *req)
+void __fuse_get_request(struct fuse_req *req)
{
atomic_inc(&req->count);
}
@@ -130,20 +130,30 @@ static void fuse_req_init_context(struct fuse_req *req)
req->in.h.pid = current->pid;
}
-struct fuse_req *fuse_get_req(struct fuse_conn *fc, unsigned npages)
+static bool fuse_block_alloc(struct fuse_conn *fc, bool for_background)
+{
+ return !fc->initialized || (for_background && fc->blocked);
+}
+
+static struct fuse_req *__fuse_get_req(struct fuse_conn *fc, unsigned npages,
+ bool for_background)
{
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;
+
+ 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)
@@ -151,19 +161,35 @@ struct fuse_req *fuse_get_req(struct fuse_conn *fc, unsigned npages)
req = fuse_request_alloc(npages);
err = -ENOMEM;
- if (!req)
+ 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);
}
+
+struct fuse_req *fuse_get_req(struct fuse_conn *fc, unsigned npages)
+{
+ return __fuse_get_req(fc, npages, false);
+}
EXPORT_SYMBOL_GPL(fuse_get_req);
+struct fuse_req *fuse_get_req_for_background(struct fuse_conn *fc,
+ unsigned npages)
+{
+ return __fuse_get_req(fc, npages, true);
+}
+EXPORT_SYMBOL_GPL(fuse_get_req_for_background);
+
/*
* Return request in fuse_file->reserved_req. However that may
* currently be in use. If that is the case, wait for it to become
@@ -225,19 +251,31 @@ struct fuse_req *fuse_get_req_nofail_nopages(struct fuse_conn *fc,
struct fuse_req *req;
atomic_inc(&fc->num_waiting);
- wait_event(fc->blocked_waitq, !fc->blocked);
+ wait_event(fc->blocked_waitq, fc->initialized);
req = fuse_request_alloc(0);
if (!req)
req = get_reserved_req(fc, file);
fuse_req_init_context(req);
req->waiting = 1;
+ req->background = 0;
return req;
}
void fuse_put_request(struct fuse_conn *fc, struct fuse_req *req)
{
if (atomic_dec_and_test(&req->count)) {
+ if (unlikely(req->background)) {
+ /*
+ * We get here in the unlikely case that a background
+ * request was allocated but not sent
+ */
+ spin_lock(&fc->lock);
+ if (!fc->blocked)
+ wake_up(&fc->blocked_waitq);
+ spin_unlock(&fc->lock);
+ }
+
if (req->waiting)
atomic_dec(&fc->num_waiting);
@@ -335,10 +373,15 @@ __releases(fc->lock)
list_del(&req->intr_entry);
req->state = FUSE_REQ_FINISHED;
if (req->background) {
- if (fc->num_background == fc->max_background) {
+ req->background = 0;
+
+ if (fc->num_background == fc->max_background)
fc->blocked = 0;
- wake_up_all(&fc->blocked_waitq);
- }
+
+ /* Wake up next waiter, if any */
+ if (!fc->blocked && waitqueue_active(&fc->blocked_waitq))
+ wake_up(&fc->blocked_waitq);
+
if (fc->num_background == fc->congestion_threshold &&
fc->connected && fc->bdi_initialized) {
clear_bdi_congested(&fc->bdi, BLK_RW_SYNC);
@@ -442,6 +485,7 @@ __acquires(fc->lock)
static void __fuse_request_send(struct fuse_conn *fc, struct fuse_req *req)
{
+ BUG_ON(req->background);
spin_lock(&fc->lock);
if (!fc->connected)
req->out.h.error = -ENOTCONN;
@@ -469,7 +513,7 @@ EXPORT_SYMBOL_GPL(fuse_request_send);
static void fuse_request_send_nowait_locked(struct fuse_conn *fc,
struct fuse_req *req)
{
- req->background = 1;
+ BUG_ON(!req->background);
fc->num_background++;
if (fc->num_background == fc->max_background)
fc->blocked = 1;
@@ -2071,6 +2115,7 @@ void fuse_abort_conn(struct fuse_conn *fc)
if (fc->connected) {
fc->connected = 0;
fc->blocked = 0;
+ fc->initialized = 1;
end_io_requests(fc);
end_queued_requests(fc);
end_polls(fc);
@@ -2089,6 +2134,7 @@ int fuse_dev_release(struct inode *inode, struct file *file)
spin_lock(&fc->lock);
fc->connected = 0;
fc->blocked = 0;
+ fc->initialized = 1;
end_queued_requests(fc);
end_polls(fc);
wake_up_all(&fc->blocked_waitq);