diff options
Diffstat (limited to 'drivers/block/virtio_blk.c')
| -rw-r--r-- | drivers/block/virtio_blk.c | 87 |
1 files changed, 80 insertions, 7 deletions
diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c index 4d0b70adf5f..ffd5ca91929 100644 --- a/drivers/block/virtio_blk.c +++ b/drivers/block/virtio_blk.c @@ -4,6 +4,7 @@ #include <linux/blkdev.h> #include <linux/hdreg.h> #include <linux/module.h> +#include <linux/mutex.h> #include <linux/virtio.h> #include <linux/virtio_blk.h> #include <linux/scatterlist.h> @@ -36,6 +37,12 @@ struct virtio_blk /* Process context for config space updates */ struct work_struct config_work; + /* Lock for config space updates */ + struct mutex config_lock; + + /* enable config space updates */ + bool config_enable; + /* What host tells us, plus 2 for header & tailer. */ unsigned int sg_elems; @@ -172,7 +179,7 @@ static bool do_req(struct request_queue *q, struct virtio_blk *vblk, } } - if (virtqueue_add_buf(vblk->vq, vblk->sg, out, in, vbr) < 0) { + if (virtqueue_add_buf(vblk->vq, vblk->sg, out, in, vbr, GFP_ATOMIC)<0) { mempool_free(vbr, vblk->pool); return false; } @@ -318,6 +325,10 @@ static void virtblk_config_changed_work(struct work_struct *work) char cap_str_2[10], cap_str_10[10]; u64 capacity, size; + mutex_lock(&vblk->config_lock); + if (!vblk->config_enable) + goto done; + /* Host must always specify the capacity. */ vdev->config->get(vdev, offsetof(struct virtio_blk_config, capacity), &capacity, sizeof(capacity)); @@ -340,6 +351,8 @@ static void virtblk_config_changed_work(struct work_struct *work) cap_str_10, cap_str_2); set_capacity(vblk->disk, capacity); +done: + mutex_unlock(&vblk->config_lock); } static void virtblk_config_changed(struct virtio_device *vdev) @@ -349,6 +362,18 @@ static void virtblk_config_changed(struct virtio_device *vdev) queue_work(virtblk_wq, &vblk->config_work); } +static int init_vq(struct virtio_blk *vblk) +{ + int err = 0; + + /* We expect one virtqueue, for output. */ + vblk->vq = virtio_find_single_vq(vblk->vdev, blk_done, "requests"); + if (IS_ERR(vblk->vq)) + err = PTR_ERR(vblk->vq); + + return err; +} + static int __devinit virtblk_probe(struct virtio_device *vdev) { struct virtio_blk *vblk; @@ -388,14 +413,13 @@ static int __devinit virtblk_probe(struct virtio_device *vdev) vblk->vdev = vdev; vblk->sg_elems = sg_elems; sg_init_table(vblk->sg, vblk->sg_elems); + mutex_init(&vblk->config_lock); INIT_WORK(&vblk->config_work, virtblk_config_changed_work); + vblk->config_enable = true; - /* We expect one virtqueue, for output. */ - vblk->vq = virtio_find_single_vq(vdev, blk_done, "requests"); - if (IS_ERR(vblk->vq)) { - err = PTR_ERR(vblk->vq); + err = init_vq(vblk); + if (err) goto out_free_vblk; - } vblk->pool = mempool_create_kmalloc_pool(1,sizeof(struct virtblk_req)); if (!vblk->pool) { @@ -542,7 +566,10 @@ static void __devexit virtblk_remove(struct virtio_device *vdev) struct virtio_blk *vblk = vdev->priv; int index = vblk->index; - flush_work(&vblk->config_work); + /* Prevent config work handler from accessing the device. */ + mutex_lock(&vblk->config_lock); + vblk->config_enable = false; + mutex_unlock(&vblk->config_lock); /* Nothing should be pending. */ BUG_ON(!list_empty(&vblk->reqs)); @@ -550,6 +577,8 @@ static void __devexit virtblk_remove(struct virtio_device *vdev) /* Stop all the virtqueues. */ vdev->config->reset(vdev); + flush_work(&vblk->config_work); + del_gendisk(vblk->disk); blk_cleanup_queue(vblk->disk->queue); put_disk(vblk->disk); @@ -559,6 +588,46 @@ static void __devexit virtblk_remove(struct virtio_device *vdev) ida_simple_remove(&vd_index_ida, index); } +#ifdef CONFIG_PM +static int virtblk_freeze(struct virtio_device *vdev) +{ + struct virtio_blk *vblk = vdev->priv; + + /* Ensure we don't receive any more interrupts */ + vdev->config->reset(vdev); + + /* Prevent config work handler from accessing the device. */ + mutex_lock(&vblk->config_lock); + vblk->config_enable = false; + mutex_unlock(&vblk->config_lock); + + flush_work(&vblk->config_work); + + spin_lock_irq(vblk->disk->queue->queue_lock); + blk_stop_queue(vblk->disk->queue); + spin_unlock_irq(vblk->disk->queue->queue_lock); + blk_sync_queue(vblk->disk->queue); + + vdev->config->del_vqs(vdev); + return 0; +} + +static int virtblk_restore(struct virtio_device *vdev) +{ + struct virtio_blk *vblk = vdev->priv; + int ret; + + vblk->config_enable = true; + ret = init_vq(vdev->priv); + if (!ret) { + spin_lock_irq(vblk->disk->queue->queue_lock); + blk_start_queue(vblk->disk->queue); + spin_unlock_irq(vblk->disk->queue->queue_lock); + } + return ret; +} +#endif + static const struct virtio_device_id id_table[] = { { VIRTIO_ID_BLOCK, VIRTIO_DEV_ANY_ID }, { 0 }, @@ -584,6 +653,10 @@ static struct virtio_driver __refdata virtio_blk = { .probe = virtblk_probe, .remove = __devexit_p(virtblk_remove), .config_changed = virtblk_config_changed, +#ifdef CONFIG_PM + .freeze = virtblk_freeze, + .restore = virtblk_restore, +#endif }; static int __init init(void) |