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Diffstat (limited to 'fs/fuse/virtio_fs.c')
-rw-r--r--fs/fuse/virtio_fs.c169
1 files changed, 113 insertions, 56 deletions
diff --git a/fs/fuse/virtio_fs.c b/fs/fuse/virtio_fs.c
index 6af3f131e468..a5c86048b96e 100644
--- a/fs/fuse/virtio_fs.c
+++ b/fs/fuse/virtio_fs.c
@@ -30,6 +30,7 @@ struct virtio_fs_vq {
struct virtqueue *vq; /* protected by ->lock */
struct work_struct done_work;
struct list_head queued_reqs;
+ struct list_head end_reqs; /* End these requests */
struct delayed_work dispatch_work;
struct fuse_dev *fud;
bool connected;
@@ -54,6 +55,9 @@ struct virtio_fs_forget {
struct list_head list;
};
+static int virtio_fs_enqueue_req(struct virtio_fs_vq *fsvq,
+ struct fuse_req *req, bool in_flight);
+
static inline struct virtio_fs_vq *vq_to_fsvq(struct virtqueue *vq)
{
struct virtio_fs *fs = vq->vdev->priv;
@@ -66,6 +70,19 @@ static inline struct fuse_pqueue *vq_to_fpq(struct virtqueue *vq)
return &vq_to_fsvq(vq)->fud->pq;
}
+/* Should be called with fsvq->lock held. */
+static inline void inc_in_flight_req(struct virtio_fs_vq *fsvq)
+{
+ fsvq->in_flight++;
+}
+
+/* Should be called with fsvq->lock held. */
+static inline void dec_in_flight_req(struct virtio_fs_vq *fsvq)
+{
+ WARN_ON(fsvq->in_flight <= 0);
+ fsvq->in_flight--;
+}
+
static void release_virtio_fs_obj(struct kref *ref)
{
struct virtio_fs *vfs = container_of(ref, struct virtio_fs, refcount);
@@ -109,22 +126,6 @@ static void virtio_fs_drain_queue(struct virtio_fs_vq *fsvq)
flush_delayed_work(&fsvq->dispatch_work);
}
-static inline void drain_hiprio_queued_reqs(struct virtio_fs_vq *fsvq)
-{
- struct virtio_fs_forget *forget;
-
- spin_lock(&fsvq->lock);
- while (1) {
- forget = list_first_entry_or_null(&fsvq->queued_reqs,
- struct virtio_fs_forget, list);
- if (!forget)
- break;
- list_del(&forget->list);
- kfree(forget);
- }
- spin_unlock(&fsvq->lock);
-}
-
static void virtio_fs_drain_all_queues(struct virtio_fs *fs)
{
struct virtio_fs_vq *fsvq;
@@ -132,9 +133,6 @@ static void virtio_fs_drain_all_queues(struct virtio_fs *fs)
for (i = 0; i < fs->nvqs; i++) {
fsvq = &fs->vqs[i];
- if (i == VQ_HIPRIO)
- drain_hiprio_queued_reqs(fsvq);
-
virtio_fs_drain_queue(fsvq);
}
}
@@ -253,14 +251,66 @@ static void virtio_fs_hiprio_done_work(struct work_struct *work)
while ((req = virtqueue_get_buf(vq, &len)) != NULL) {
kfree(req);
- fsvq->in_flight--;
+ dec_in_flight_req(fsvq);
}
} while (!virtqueue_enable_cb(vq) && likely(!virtqueue_is_broken(vq)));
spin_unlock(&fsvq->lock);
}
-static void virtio_fs_dummy_dispatch_work(struct work_struct *work)
+static void virtio_fs_request_dispatch_work(struct work_struct *work)
{
+ struct fuse_req *req;
+ struct virtio_fs_vq *fsvq = container_of(work, struct virtio_fs_vq,
+ dispatch_work.work);
+ struct fuse_conn *fc = fsvq->fud->fc;
+ int ret;
+
+ pr_debug("virtio-fs: worker %s called.\n", __func__);
+ while (1) {
+ spin_lock(&fsvq->lock);
+ req = list_first_entry_or_null(&fsvq->end_reqs, struct fuse_req,
+ list);
+ if (!req) {
+ spin_unlock(&fsvq->lock);
+ break;
+ }
+
+ list_del_init(&req->list);
+ spin_unlock(&fsvq->lock);
+ fuse_request_end(fc, req);
+ }
+
+ /* Dispatch pending requests */
+ while (1) {
+ spin_lock(&fsvq->lock);
+ req = list_first_entry_or_null(&fsvq->queued_reqs,
+ struct fuse_req, list);
+ if (!req) {
+ spin_unlock(&fsvq->lock);
+ return;
+ }
+ list_del_init(&req->list);
+ spin_unlock(&fsvq->lock);
+
+ ret = virtio_fs_enqueue_req(fsvq, req, true);
+ if (ret < 0) {
+ if (ret == -ENOMEM || ret == -ENOSPC) {
+ spin_lock(&fsvq->lock);
+ list_add_tail(&req->list, &fsvq->queued_reqs);
+ schedule_delayed_work(&fsvq->dispatch_work,
+ msecs_to_jiffies(1));
+ spin_unlock(&fsvq->lock);
+ return;
+ }
+ req->out.h.error = ret;
+ spin_lock(&fsvq->lock);
+ dec_in_flight_req(fsvq);
+ spin_unlock(&fsvq->lock);
+ pr_err("virtio-fs: virtio_fs_enqueue_req() failed %d\n",
+ ret);
+ fuse_request_end(fc, req);
+ }
+ }
}
static void virtio_fs_hiprio_dispatch_work(struct work_struct *work)
@@ -286,6 +336,7 @@ static void virtio_fs_hiprio_dispatch_work(struct work_struct *work)
list_del(&forget->list);
if (!fsvq->connected) {
+ dec_in_flight_req(fsvq);
spin_unlock(&fsvq->lock);
kfree(forget);
continue;
@@ -307,13 +358,13 @@ static void virtio_fs_hiprio_dispatch_work(struct work_struct *work)
} else {
pr_debug("virtio-fs: Could not queue FORGET: err=%d. Dropping it.\n",
ret);
+ dec_in_flight_req(fsvq);
kfree(forget);
}
spin_unlock(&fsvq->lock);
return;
}
- fsvq->in_flight++;
notify = virtqueue_kick_prepare(vq);
spin_unlock(&fsvq->lock);
@@ -452,7 +503,7 @@ static void virtio_fs_requests_done_work(struct work_struct *work)
fuse_request_end(fc, req);
spin_lock(&fsvq->lock);
- fsvq->in_flight--;
+ dec_in_flight_req(fsvq);
spin_unlock(&fsvq->lock);
}
}
@@ -502,6 +553,7 @@ static int virtio_fs_setup_vqs(struct virtio_device *vdev,
names[VQ_HIPRIO] = fs->vqs[VQ_HIPRIO].name;
INIT_WORK(&fs->vqs[VQ_HIPRIO].done_work, virtio_fs_hiprio_done_work);
INIT_LIST_HEAD(&fs->vqs[VQ_HIPRIO].queued_reqs);
+ INIT_LIST_HEAD(&fs->vqs[VQ_HIPRIO].end_reqs);
INIT_DELAYED_WORK(&fs->vqs[VQ_HIPRIO].dispatch_work,
virtio_fs_hiprio_dispatch_work);
spin_lock_init(&fs->vqs[VQ_HIPRIO].lock);
@@ -511,8 +563,9 @@ static int virtio_fs_setup_vqs(struct virtio_device *vdev,
spin_lock_init(&fs->vqs[i].lock);
INIT_WORK(&fs->vqs[i].done_work, virtio_fs_requests_done_work);
INIT_DELAYED_WORK(&fs->vqs[i].dispatch_work,
- virtio_fs_dummy_dispatch_work);
+ virtio_fs_request_dispatch_work);
INIT_LIST_HEAD(&fs->vqs[i].queued_reqs);
+ INIT_LIST_HEAD(&fs->vqs[i].end_reqs);
snprintf(fs->vqs[i].name, sizeof(fs->vqs[i].name),
"requests.%u", i - VQ_REQUEST);
callbacks[i] = virtio_fs_vq_done;
@@ -708,6 +761,7 @@ __releases(fiq->lock)
list_add_tail(&forget->list, &fsvq->queued_reqs);
schedule_delayed_work(&fsvq->dispatch_work,
msecs_to_jiffies(1));
+ inc_in_flight_req(fsvq);
} else {
pr_debug("virtio-fs: Could not queue FORGET: err=%d. Dropping it.\n",
ret);
@@ -717,7 +771,7 @@ __releases(fiq->lock)
goto out;
}
- fsvq->in_flight++;
+ inc_in_flight_req(fsvq);
notify = virtqueue_kick_prepare(vq);
spin_unlock(&fsvq->lock);
@@ -819,7 +873,7 @@ static unsigned int sg_init_fuse_args(struct scatterlist *sg,
/* Add a request to a virtqueue and kick the device */
static int virtio_fs_enqueue_req(struct virtio_fs_vq *fsvq,
- struct fuse_req *req)
+ struct fuse_req *req, bool in_flight)
{
/* requests need at least 4 elements */
struct scatterlist *stack_sgs[6];
@@ -835,6 +889,7 @@ static int virtio_fs_enqueue_req(struct virtio_fs_vq *fsvq,
unsigned int i;
int ret;
bool notify;
+ struct fuse_pqueue *fpq;
/* Does the sglist fit on the stack? */
total_sgs = sg_count_fuse_req(req);
@@ -889,7 +944,17 @@ static int virtio_fs_enqueue_req(struct virtio_fs_vq *fsvq,
goto out;
}
- fsvq->in_flight++;
+ /* Request successfully sent. */
+ fpq = &fsvq->fud->pq;
+ spin_lock(&fpq->lock);
+ list_add_tail(&req->list, fpq->processing);
+ spin_unlock(&fpq->lock);
+ set_bit(FR_SENT, &req->flags);
+ /* matches barrier in request_wait_answer() */
+ smp_mb__after_atomic();
+
+ if (!in_flight)
+ inc_in_flight_req(fsvq);
notify = virtqueue_kick_prepare(vq);
spin_unlock(&fsvq->lock);
@@ -915,9 +980,8 @@ __releases(fiq->lock)
{
unsigned int queue_id = VQ_REQUEST; /* TODO multiqueue */
struct virtio_fs *fs;
- struct fuse_conn *fc;
struct fuse_req *req;
- struct fuse_pqueue *fpq;
+ struct virtio_fs_vq *fsvq;
int ret;
WARN_ON(list_empty(&fiq->pending));
@@ -928,44 +992,36 @@ __releases(fiq->lock)
spin_unlock(&fiq->lock);
fs = fiq->priv;
- fc = fs->vqs[queue_id].fud->fc;
pr_debug("%s: opcode %u unique %#llx nodeid %#llx in.len %u out.len %u\n",
__func__, req->in.h.opcode, req->in.h.unique,
req->in.h.nodeid, req->in.h.len,
fuse_len_args(req->args->out_numargs, req->args->out_args));
- fpq = &fs->vqs[queue_id].fud->pq;
- spin_lock(&fpq->lock);
- if (!fpq->connected) {
- spin_unlock(&fpq->lock);
- req->out.h.error = -ENODEV;
- pr_err("virtio-fs: %s disconnected\n", __func__);
- fuse_request_end(fc, req);
- return;
- }
- list_add_tail(&req->list, fpq->processing);
- spin_unlock(&fpq->lock);
- set_bit(FR_SENT, &req->flags);
- /* matches barrier in request_wait_answer() */
- smp_mb__after_atomic();
-
-retry:
- ret = virtio_fs_enqueue_req(&fs->vqs[queue_id], req);
+ fsvq = &fs->vqs[queue_id];
+ ret = virtio_fs_enqueue_req(fsvq, req, false);
if (ret < 0) {
if (ret == -ENOMEM || ret == -ENOSPC) {
- /* Virtqueue full. Retry submission */
- /* TODO use completion instead of timeout */
- usleep_range(20, 30);
- goto retry;
+ /*
+ * Virtqueue full. Retry submission from worker
+ * context as we might be holding fc->bg_lock.
+ */
+ spin_lock(&fsvq->lock);
+ list_add_tail(&req->list, &fsvq->queued_reqs);
+ inc_in_flight_req(fsvq);
+ schedule_delayed_work(&fsvq->dispatch_work,
+ msecs_to_jiffies(1));
+ spin_unlock(&fsvq->lock);
+ return;
}
req->out.h.error = ret;
pr_err("virtio-fs: virtio_fs_enqueue_req() failed %d\n", ret);
- spin_lock(&fpq->lock);
- clear_bit(FR_SENT, &req->flags);
- list_del_init(&req->list);
- spin_unlock(&fpq->lock);
- fuse_request_end(fc, req);
+
+ /* Can't end request in submission context. Use a worker */
+ spin_lock(&fsvq->lock);
+ list_add_tail(&req->list, &fsvq->end_reqs);
+ schedule_delayed_work(&fsvq->dispatch_work, 0);
+ spin_unlock(&fsvq->lock);
return;
}
}
@@ -992,6 +1048,7 @@ static int virtio_fs_fill_super(struct super_block *sb)
.destroy = true,
.no_control = true,
.no_force_umount = true,
+ .no_mount_options = true,
};
mutex_lock(&virtio_fs_mutex);