diff --git a/Documentation/DMA-API.txt b/Documentation/DMA-API.txt
index 5866436429102115551094fca971245f4b9e6439..0076150fdccbbc1276047f39ff5496edc93b492a 100644
--- a/Documentation/DMA-API.txt
+++ b/Documentation/DMA-API.txt
@@ -195,6 +195,14 @@ Requesting the required mask does not alter the current mask. If you
wish to take advantage of it, you should issue a dma_set_mask()
call to set the mask to the value returned.
+::
+
+ size_t
+ dma_direct_max_mapping_size(struct device *dev);
+
+Returns the maximum size of a mapping for the device. The size parameter
+of the mapping functions like dma_map_single(), dma_map_page() and
+others should not be larger than the returned value.
Part Id - Streaming DMA mappings
--------------------------------
diff --git a/Documentation/virtual/kvm/s390-diag.txt b/Documentation/virtual/kvm/s390-diag.txt
index 48c4921794edf0b98c9dfb59e0361b235d3124e2..7c52e5f8b210357075cc115500638c4b5841bab9 100644
--- a/Documentation/virtual/kvm/s390-diag.txt
+++ b/Documentation/virtual/kvm/s390-diag.txt
@@ -68,7 +68,8 @@ Subcode 3 - virtio-ccw notification
identifier, it is ignored.
After completion of the DIAGNOSE call, general register 2 may contain
- a 64bit identifier (in the kvm_io_bus cookie case).
+ a 64bit identifier (in the kvm_io_bus cookie case), or a negative
+ error value, if an internal error occurred.
See also the virtio standard for a discussion of this hypercall.
diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c
index b16a887bbd02a8b7715fb85a812c73f75a2d25fe..4bc083b7c9b541a0fede52156bdae003c1d678df 100644
--- a/drivers/block/virtio_blk.c
+++ b/drivers/block/virtio_blk.c
@@ -723,7 +723,7 @@ static int virtblk_probe(struct virtio_device *vdev)
struct request_queue *q;
int err, index;
- u32 v, blk_size, sg_elems, opt_io_size;
+ u32 v, blk_size, max_size, sg_elems, opt_io_size;
u16 min_io_size;
u8 physical_block_exp, alignment_offset;
@@ -826,14 +826,16 @@ static int virtblk_probe(struct virtio_device *vdev)
/* No real sector limit. */
blk_queue_max_hw_sectors(q, -1U);
+ max_size = virtio_max_dma_size(vdev);
+
/* Host can optionally specify maximum segment size and number of
* segments. */
err = virtio_cread_feature(vdev, VIRTIO_BLK_F_SIZE_MAX,
struct virtio_blk_config, size_max, &v);
if (!err)
- blk_queue_max_segment_size(q, v);
- else
- blk_queue_max_segment_size(q, -1U);
+ max_size = min(max_size, v);
+
+ blk_queue_max_segment_size(q, max_size);
/* Host can optionally specify the block size of the device */
err = virtio_cread_feature(vdev, VIRTIO_BLK_F_BLK_SIZE,
diff --git a/drivers/s390/virtio/virtio_ccw.c b/drivers/s390/virtio/virtio_ccw.c
index ae1d56da671dfe9eab824e379d7d482b639dacf2..74c328321889b1fa3265385ebe9d0a201a031b90 100644
--- a/drivers/s390/virtio/virtio_ccw.c
+++ b/drivers/s390/virtio/virtio_ccw.c
@@ -272,6 +272,8 @@ static void virtio_ccw_drop_indicators(struct virtio_ccw_device *vcdev)
{
struct virtio_ccw_vq_info *info;
+ if (!vcdev->airq_info)
+ return;
list_for_each_entry(info, &vcdev->virtqueues, node)
drop_airq_indicator(info->vq, vcdev->airq_info);
}
@@ -413,7 +415,7 @@ static int virtio_ccw_read_vq_conf(struct virtio_ccw_device *vcdev,
ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_VQ_CONF);
if (ret)
return ret;
- return vcdev->config_block->num;
+ return vcdev->config_block->num ?: -ENOENT;
}
static void virtio_ccw_del_vq(struct virtqueue *vq, struct ccw1 *ccw)
@@ -973,6 +975,13 @@ static void virtio_ccw_set_status(struct virtio_device *vdev, u8 status)
kfree(ccw);
}
+static const char *virtio_ccw_bus_name(struct virtio_device *vdev)
+{
+ struct virtio_ccw_device *vcdev = to_vc_device(vdev);
+
+ return dev_name(&vcdev->cdev->dev);
+}
+
static const struct virtio_config_ops virtio_ccw_config_ops = {
.get_features = virtio_ccw_get_features,
.finalize_features = virtio_ccw_finalize_features,
@@ -983,6 +992,7 @@ static const struct virtio_config_ops virtio_ccw_config_ops = {
.reset = virtio_ccw_reset,
.find_vqs = virtio_ccw_find_vqs,
.del_vqs = virtio_ccw_del_vqs,
+ .bus_name = virtio_ccw_bus_name,
};
diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
index a2e5dc7716e21c7cbed163159a0c1262df977227..5ace833de74620bf1a089186057d766e7e3def63 100644
--- a/drivers/vhost/vhost.c
+++ b/drivers/vhost/vhost.c
@@ -1188,7 +1188,7 @@ static bool vq_access_ok(struct vhost_virtqueue *vq, unsigned int num,
struct vring_used __user *used)
{
- size_t s = vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0;
+ size_t s __maybe_unused = vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0;
return access_ok(desc, num * sizeof *desc) &&
access_ok(avail,
diff --git a/drivers/virtio/virtio.c b/drivers/virtio/virtio.c
index 59e36ef4920f670bb7ff520844d02e8e72ece81e..98b30f54342c0abc9a1de687d317dd0eea43e1b1 100644
--- a/drivers/virtio/virtio.c
+++ b/drivers/virtio/virtio.c
@@ -161,6 +161,7 @@ EXPORT_SYMBOL_GPL(virtio_config_enable);
void virtio_add_status(struct virtio_device *dev, unsigned int status)
{
+ might_sleep();
dev->config->set_status(dev, dev->config->get_status(dev) | status);
}
EXPORT_SYMBOL_GPL(virtio_add_status);
@@ -170,6 +171,7 @@ int virtio_finalize_features(struct virtio_device *dev)
int ret = dev->config->finalize_features(dev);
unsigned status;
+ might_sleep();
if (ret)
return ret;
diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c
index fb12fe205f86669b68a885c4e377e0342bb9ed85..f19061b585a4f73a1fbecd1876592db4a6a39fee 100644
--- a/drivers/virtio/virtio_balloon.c
+++ b/drivers/virtio/virtio_balloon.c
@@ -457,9 +457,12 @@ static void update_balloon_size_func(struct work_struct *work)
update_balloon_size_work);
diff = towards_target(vb);
+ if (!diff)
+ return;
+
if (diff > 0)
diff -= fill_balloon(vb, diff);
- else if (diff < 0)
+ else
diff += leak_balloon(vb, -diff);
update_balloon_size(vb);
@@ -922,7 +925,6 @@ static int virtballoon_probe(struct virtio_device *vdev)
VIRTIO_BALLOON_CMD_ID_STOP);
vb->cmd_id_stop = cpu_to_virtio32(vb->vdev,
VIRTIO_BALLOON_CMD_ID_STOP);
- vb->num_free_page_blocks = 0;
spin_lock_init(&vb->free_page_list_lock);
INIT_LIST_HEAD(&vb->free_page_list);
if (virtio_has_feature(vdev, VIRTIO_BALLOON_F_PAGE_POISON)) {
diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
index a0b07c3312550463b689acf9aa8d524ac5ad7d89..18846afb39da189e3f0dd0168727e0cf2865549e 100644
--- a/drivers/virtio/virtio_ring.c
+++ b/drivers/virtio/virtio_ring.c
@@ -271,6 +271,17 @@ static bool vring_use_dma_api(struct virtio_device *vdev)
return false;
}
+size_t virtio_max_dma_size(struct virtio_device *vdev)
+{
+ size_t max_segment_size = SIZE_MAX;
+
+ if (vring_use_dma_api(vdev))
+ max_segment_size = dma_max_mapping_size(&vdev->dev);
+
+ return max_segment_size;
+}
+EXPORT_SYMBOL_GPL(virtio_max_dma_size);
+
static void *vring_alloc_queue(struct virtio_device *vdev, size_t size,
dma_addr_t *dma_handle, gfp_t flag)
{
diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h
index 70ad15758a7027de406e4cc5d4de95c16f579f08..75e60be91e5f3f6bae493c8784da79a77db47aab 100644
--- a/include/linux/dma-mapping.h
+++ b/include/linux/dma-mapping.h
@@ -130,6 +130,7 @@ struct dma_map_ops {
enum dma_data_direction direction);
int (*dma_supported)(struct device *dev, u64 mask);
u64 (*get_required_mask)(struct device *dev);
+ size_t (*max_mapping_size)(struct device *dev);
};
#define DMA_MAPPING_ERROR (~(dma_addr_t)0)
@@ -259,6 +260,8 @@ static inline void dma_direct_sync_sg_for_cpu(struct device *dev,
}
#endif
+size_t dma_direct_max_mapping_size(struct device *dev);
+
#ifdef CONFIG_HAS_DMA
#include <asm/dma-mapping.h>
@@ -463,6 +466,7 @@ int dma_supported(struct device *dev, u64 mask);
int dma_set_mask(struct device *dev, u64 mask);
int dma_set_coherent_mask(struct device *dev, u64 mask);
u64 dma_get_required_mask(struct device *dev);
+size_t dma_max_mapping_size(struct device *dev);
#else /* CONFIG_HAS_DMA */
static inline dma_addr_t dma_map_page_attrs(struct device *dev,
struct page *page, size_t offset, size_t size,
@@ -564,6 +568,10 @@ static inline u64 dma_get_required_mask(struct device *dev)
{
return 0;
}
+static inline size_t dma_max_mapping_size(struct device *dev)
+{
+ return 0;
+}
#endif /* CONFIG_HAS_DMA */
static inline dma_addr_t dma_map_single_attrs(struct device *dev, void *ptr,
diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h
index 54254388899e589431f80b29ab7f387f44822fe6..361f62bb4a8e92efd26e3f0d91e65193085dcb3b 100644
--- a/include/linux/swiotlb.h
+++ b/include/linux/swiotlb.h
@@ -73,6 +73,8 @@ bool swiotlb_map(struct device *dev, phys_addr_t *phys, dma_addr_t *dma_addr,
size_t size, enum dma_data_direction dir, unsigned long attrs);
void __init swiotlb_exit(void);
unsigned int swiotlb_max_segment(void);
+size_t swiotlb_max_mapping_size(struct device *dev);
+bool is_swiotlb_active(void);
#else
#define swiotlb_force SWIOTLB_NO_FORCE
static inline bool is_swiotlb_buffer(phys_addr_t paddr)
@@ -92,6 +94,15 @@ static inline unsigned int swiotlb_max_segment(void)
{
return 0;
}
+static inline size_t swiotlb_max_mapping_size(struct device *dev)
+{
+ return SIZE_MAX;
+}
+
+static inline bool is_swiotlb_active(void)
+{
+ return false;
+}
#endif /* CONFIG_SWIOTLB */
extern void swiotlb_print_info(void);
diff --git a/include/linux/virtio.h b/include/linux/virtio.h
index fa1b5da2804e6041df3b8f47e5ce0c7ddf828a54..673fe3ef360788642edf1f4c448f3618a556373f 100644
--- a/include/linux/virtio.h
+++ b/include/linux/virtio.h
@@ -157,6 +157,8 @@ int virtio_device_freeze(struct virtio_device *dev);
int virtio_device_restore(struct virtio_device *dev);
#endif
+size_t virtio_max_dma_size(struct virtio_device *vdev);
+
#define virtio_device_for_each_vq(vdev, vq) \
list_for_each_entry(vq, &vdev->vqs, list)
diff --git a/include/linux/virtio_config.h b/include/linux/virtio_config.h
index 987b6491b9461bfe33c9d1306999da1c21c9f63d..bb4cc49107503c23c09ad3413189d5de29657a42 100644
--- a/include/linux/virtio_config.h
+++ b/include/linux/virtio_config.h
@@ -290,6 +290,7 @@ static inline __virtio64 cpu_to_virtio64(struct virtio_device *vdev, u64 val)
/* Config space accessors. */
#define virtio_cread(vdev, structname, member, ptr) \
do { \
+ might_sleep(); \
/* Must match the member's type, and be integer */ \
if (!typecheck(typeof((((structname*)0)->member)), *(ptr))) \
(*ptr) = 1; \
@@ -319,6 +320,7 @@ static inline __virtio64 cpu_to_virtio64(struct virtio_device *vdev, u64 val)
/* Config space accessors. */
#define virtio_cwrite(vdev, structname, member, ptr) \
do { \
+ might_sleep(); \
/* Must match the member's type, and be integer */ \
if (!typecheck(typeof((((structname*)0)->member)), *(ptr))) \
BUG_ON((*ptr) == 1); \
@@ -358,6 +360,7 @@ static inline void __virtio_cread_many(struct virtio_device *vdev,
vdev->config->generation(vdev) : 0;
int i;
+ might_sleep();
do {
old = gen;
@@ -380,6 +383,8 @@ static inline void virtio_cread_bytes(struct virtio_device *vdev,
static inline u8 virtio_cread8(struct virtio_device *vdev, unsigned int offset)
{
u8 ret;
+
+ might_sleep();
vdev->config->get(vdev, offset, &ret, sizeof(ret));
return ret;
}
@@ -387,6 +392,7 @@ static inline u8 virtio_cread8(struct virtio_device *vdev, unsigned int offset)
static inline void virtio_cwrite8(struct virtio_device *vdev,
unsigned int offset, u8 val)
{
+ might_sleep();
vdev->config->set(vdev, offset, &val, sizeof(val));
}
@@ -394,6 +400,8 @@ static inline u16 virtio_cread16(struct virtio_device *vdev,
unsigned int offset)
{
u16 ret;
+
+ might_sleep();
vdev->config->get(vdev, offset, &ret, sizeof(ret));
return virtio16_to_cpu(vdev, (__force __virtio16)ret);
}
@@ -401,6 +409,7 @@ static inline u16 virtio_cread16(struct virtio_device *vdev,
static inline void virtio_cwrite16(struct virtio_device *vdev,
unsigned int offset, u16 val)
{
+ might_sleep();
val = (__force u16)cpu_to_virtio16(vdev, val);
vdev->config->set(vdev, offset, &val, sizeof(val));
}
@@ -409,6 +418,8 @@ static inline u32 virtio_cread32(struct virtio_device *vdev,
unsigned int offset)
{
u32 ret;
+
+ might_sleep();
vdev->config->get(vdev, offset, &ret, sizeof(ret));
return virtio32_to_cpu(vdev, (__force __virtio32)ret);
}
@@ -416,6 +427,7 @@ static inline u32 virtio_cread32(struct virtio_device *vdev,
static inline void virtio_cwrite32(struct virtio_device *vdev,
unsigned int offset, u32 val)
{
+ might_sleep();
val = (__force u32)cpu_to_virtio32(vdev, val);
vdev->config->set(vdev, offset, &val, sizeof(val));
}
@@ -431,6 +443,7 @@ static inline u64 virtio_cread64(struct virtio_device *vdev,
static inline void virtio_cwrite64(struct virtio_device *vdev,
unsigned int offset, u64 val)
{
+ might_sleep();
val = (__force u64)cpu_to_virtio64(vdev, val);
vdev->config->set(vdev, offset, &val, sizeof(val));
}
diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
index 7ff807f2121c5748dcb56b552fcc8551b0e85bdb..fcdb23e8d2fccf1e6d27f64a23a66f7878224c04 100644
--- a/kernel/dma/direct.c
+++ b/kernel/dma/direct.c
@@ -393,3 +393,14 @@ int dma_direct_supported(struct device *dev, u64 mask)
*/
return mask >= __phys_to_dma(dev, min_mask);
}
+
+size_t dma_direct_max_mapping_size(struct device *dev)
+{
+ size_t size = SIZE_MAX;
+
+ /* If SWIOTLB is active, use its maximum mapping size */
+ if (is_swiotlb_active())
+ size = swiotlb_max_mapping_size(dev);
+
+ return size;
+}
diff --git a/kernel/dma/mapping.c b/kernel/dma/mapping.c
index ef2aba503467efcf91fcc60c124893c308d03e75..c000906348c936162e1dc4cd7faa1147a57c6d8e 100644
--- a/kernel/dma/mapping.c
+++ b/kernel/dma/mapping.c
@@ -360,3 +360,17 @@ void dma_cache_sync(struct device *dev, void *vaddr, size_t size,
ops->cache_sync(dev, vaddr, size, dir);
}
EXPORT_SYMBOL(dma_cache_sync);
+
+size_t dma_max_mapping_size(struct device *dev)
+{
+ const struct dma_map_ops *ops = get_dma_ops(dev);
+ size_t size = SIZE_MAX;
+
+ if (dma_is_direct(ops))
+ size = dma_direct_max_mapping_size(dev);
+ else if (ops && ops->max_mapping_size)
+ size = ops->max_mapping_size(dev);
+
+ return size;
+}
+EXPORT_SYMBOL_GPL(dma_max_mapping_size);
diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index a9ad02d4d84e2ffa431fa6018f26a2c3f039cd6e..9f5851064aea6854b426fa34ffe3ab10588666fe 100644
--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c
@@ -666,6 +666,20 @@ bool swiotlb_map(struct device *dev, phys_addr_t *phys, dma_addr_t *dma_addr,
return true;
}
+size_t swiotlb_max_mapping_size(struct device *dev)
+{
+ return ((size_t)1 << IO_TLB_SHIFT) * IO_TLB_SEGSIZE;
+}
+
+bool is_swiotlb_active(void)
+{
+ /*
+ * When SWIOTLB is initialized, even if io_tlb_start points to physical
+ * address zero, io_tlb_end surely doesn't.
+ */
+ return io_tlb_end != 0;
+}
+
#ifdef CONFIG_DEBUG_FS
static int __init swiotlb_create_debugfs(void)