On Wed, 16 Jun 2021 at 18:09, Ioannis Angelakopoulos <iangelak@xxxxxxxxxx> wrote: > > From: Vivek Goyal <vgoyal@xxxxxxxxxx> > > We have many virtqueues and first queue which carries fuse normal requests > (except forget requests) has index pointed to by enum VQ_REQUEST. This > works fine as long as number of queues are not dynamic. > > I am about to introduce one more virtqueue, called notification queue, > which will be present only if device on host supports it. That means index > of request queue will change depending on if notification queue is present > or not. > > So, add a variable to keep track of that index and this will help when > notification queue is added in next patch. > > Signed-off-by: Vivek Goyal <vgoyal@xxxxxxxxxx> > Signed-off-by: Ioannis Angelakopoulos <iangelak@xxxxxxxxxx> > --- > fs/fuse/virtio_fs.c | 22 ++++++++++++++++------ > 1 file changed, 16 insertions(+), 6 deletions(-) > > diff --git a/fs/fuse/virtio_fs.c b/fs/fuse/virtio_fs.c > index bcb8a02e2d8b..a545e31cf1ae 100644 > --- a/fs/fuse/virtio_fs.c > +++ b/fs/fuse/virtio_fs.c > @@ -61,6 +61,7 @@ struct virtio_fs { > unsigned int nvqs; /* number of virtqueues */ > unsigned int num_request_queues; /* number of request queues */ > struct dax_device *dax_dev; > + unsigned int first_reqq_idx; /* First request queue idx */ > > /* DAX memory window where file contents are mapped */ > void *window_kaddr; > @@ -681,7 +682,9 @@ static int virtio_fs_setup_vqs(struct virtio_device *vdev, > if (fs->num_request_queues == 0) > return -EINVAL; > > - fs->nvqs = VQ_REQUEST + fs->num_request_queues; Okay, so VQ_REQUEST now completely lost it's meaning as an index into fs->vqs[] array, but VQ_HIPRIO is still used that way. This looks confusing. Let's just get rid of VQ_REQUEST/VQ_HIPRIO completely, and add "#define VQ_HIPRIO_IDX 0". > + /* One hiprio queue and rest are request queues */ > + fs->nvqs = 1 + fs->num_request_queues; > + fs->first_reqq_idx = 1; > fs->vqs = kcalloc(fs->nvqs, sizeof(fs->vqs[VQ_HIPRIO]), GFP_KERNEL); > if (!fs->vqs) > return -ENOMEM; > @@ -701,10 +704,11 @@ static int virtio_fs_setup_vqs(struct virtio_device *vdev, > names[VQ_HIPRIO] = fs->vqs[VQ_HIPRIO].name; > > /* Initialize the requests virtqueues */ > - for (i = VQ_REQUEST; i < fs->nvqs; i++) { > + for (i = fs->first_reqq_idx; i < fs->nvqs; i++) { > char vq_name[VQ_NAME_LEN]; > > - snprintf(vq_name, VQ_NAME_LEN, "requests.%u", i - VQ_REQUEST); > + snprintf(vq_name, VQ_NAME_LEN, "requests.%u", > + i - fs->first_reqq_idx); > virtio_fs_init_vq(&fs->vqs[i], vq_name, VQ_REQUEST); > callbacks[i] = virtio_fs_vq_done; > names[i] = fs->vqs[i].name; > @@ -1225,7 +1229,7 @@ static int virtio_fs_enqueue_req(struct virtio_fs_vq *fsvq, > static void virtio_fs_wake_pending_and_unlock(struct fuse_iqueue *fiq) > __releases(fiq->lock) > { > - unsigned int queue_id = VQ_REQUEST; /* TODO multiqueue */ > + unsigned int queue_id; > struct virtio_fs *fs; > struct fuse_req *req; > struct virtio_fs_vq *fsvq; > @@ -1239,6 +1243,7 @@ __releases(fiq->lock) > spin_unlock(&fiq->lock); > > fs = fiq->priv; > + queue_id = fs->first_reqq_idx; > > 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, > @@ -1316,7 +1321,7 @@ static int virtio_fs_fill_super(struct super_block *sb, struct fs_context *fsc) > > err = -ENOMEM; > /* Allocate fuse_dev for hiprio and notification queues */ > - for (i = 0; i < fs->nvqs; i++) { > + for (i = 0; i < fs->first_reqq_idx; i++) { Previous code didn't seem to do what comment said, while new code does. So while the change seems correct, it should go into a separate patch with explanation. > struct virtio_fs_vq *fsvq = &fs->vqs[i]; > > fsvq->fud = fuse_dev_alloc(); > @@ -1325,7 +1330,7 @@ static int virtio_fs_fill_super(struct super_block *sb, struct fs_context *fsc) > } > > /* virtiofs allocates and installs its own fuse devices */ > - ctx->fudptr = NULL; > + ctx->fudptr = (void **)&fs->vqs[fs->first_reqq_idx].fud; I don't understand this. > if (ctx->dax) { > if (!fs->dax_dev) { > err = -EINVAL; > @@ -1339,9 +1344,14 @@ static int virtio_fs_fill_super(struct super_block *sb, struct fs_context *fsc) > if (err < 0) > goto err_free_fuse_devs; > > + fc = fs->vqs[fs->first_reqq_idx].fud->fc; > + Nor this. > for (i = 0; i < fs->nvqs; i++) { > struct virtio_fs_vq *fsvq = &fs->vqs[i]; > > + if (i == fs->first_reqq_idx) > + continue; > + Nor this. There's something subtle going on here, that's not mentioned in the patch header. Thanks, Miklos