The f_op->mmap interface is deprecated, so update the vmbus driver to use
its successor, mmap_prepare.

This updates all callbacks which referenced the function pointer
hv_mmap_ring_buffer to instead reference hv_mmap_prepare_ring_buffer,
utilising the newly introduced compat_set_desc_from_vma() and
__compat_vma_mmap() to be able to implement this change.

The UIO HV generic driver is the only user of hv_create_ring_sysfs(), which
is the only function which references
vmbus_channel->mmap_prepare_ring_buffer which, in turn, is the only
external interface to hv_mmap_prepare_ring_buffer.

This patch therefore updates this caller to use mmap_prepare instead, which
also previously used vm_iomap_memory(), so this change replaces it
with its mmap_prepare equivalent, mmap_action_simple_ioremap().

Signed-off-by: Lorenzo Stoakes (Oracle) <[email protected]>
---
 drivers/hv/hyperv_vmbus.h    |  4 ++--
 drivers/hv/vmbus_drv.c       | 27 +++++++++++++++++----------
 drivers/uio/uio_hv_generic.c | 11 ++++++-----
 include/linux/hyperv.h       |  4 ++--
 4 files changed, 27 insertions(+), 19 deletions(-)

diff --git a/drivers/hv/hyperv_vmbus.h b/drivers/hv/hyperv_vmbus.h
index 7bd8f8486e85..31f576464f18 100644
--- a/drivers/hv/hyperv_vmbus.h
+++ b/drivers/hv/hyperv_vmbus.h
@@ -545,8 +545,8 @@ static inline int hv_debug_add_dev_dir(struct hv_device 
*dev)
 
 /* Create and remove sysfs entry for memory mapped ring buffers for a channel 
*/
 int hv_create_ring_sysfs(struct vmbus_channel *channel,
-                        int (*hv_mmap_ring_buffer)(struct vmbus_channel 
*channel,
-                                                   struct vm_area_struct 
*vma));
+                        int (*hv_mmap_prepare_ring_buffer)(struct 
vmbus_channel *channel,
+                                                           struct vm_area_desc 
*desc));
 int hv_remove_ring_sysfs(struct vmbus_channel *channel);
 
 #endif /* _HYPERV_VMBUS_H */
diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c
index bc4fc1951ae1..a76fa3f0588c 100644
--- a/drivers/hv/vmbus_drv.c
+++ b/drivers/hv/vmbus_drv.c
@@ -1951,12 +1951,19 @@ static int hv_mmap_ring_buffer_wrapper(struct file 
*filp, struct kobject *kobj,
                                       struct vm_area_struct *vma)
 {
        struct vmbus_channel *channel = container_of(kobj, struct 
vmbus_channel, kobj);
+       struct vm_area_desc desc;
+       int err;
 
        /*
         * hv_(create|remove)_ring_sysfs implementation ensures that 
mmap_ring_buffer
         * is not NULL.
         */
-       return channel->mmap_ring_buffer(channel, vma);
+       compat_set_desc_from_vma(&desc, filp, vma);
+       err = channel->mmap_prepare_ring_buffer(channel, &desc);
+       if (err)
+               return err;
+
+       return __compat_vma_mmap(&desc, vma);
 }
 
 static struct bin_attribute chan_attr_ring_buffer = {
@@ -2048,13 +2055,13 @@ static const struct kobj_type vmbus_chan_ktype = {
 /**
  * hv_create_ring_sysfs() - create "ring" sysfs entry corresponding to ring 
buffers for a channel.
  * @channel: Pointer to vmbus_channel structure
- * @hv_mmap_ring_buffer: function pointer for initializing the function to be 
called on mmap of
+ * @hv_mmap_ring_buffer: function pointer for initializing the function to be 
called on mmap
  *                       channel's "ring" sysfs node, which is for the ring 
buffer of that channel.
  *                       Function pointer is of below type:
- *                       int (*hv_mmap_ring_buffer)(struct vmbus_channel 
*channel,
- *                                                  struct vm_area_struct 
*vma))
- *                       This has a pointer to the channel and a pointer to 
vm_area_struct,
- *                       used for mmap, as arguments.
+ *                       int (*hv_mmap_prepare_ring_buffer)(struct 
vmbus_channel *channel,
+ *                                                          struct 
vm_area_desc *desc))
+ *                       This has a pointer to the channel and a pointer to 
vm_area_desc,
+ *                       used for mmap_prepare, as arguments.
  *
  * Sysfs node for ring buffer of a channel is created along with other fields, 
however its
  * visibility is disabled by default. Sysfs creation needs to be controlled 
when the use-case
@@ -2071,12 +2078,12 @@ static const struct kobj_type vmbus_chan_ktype = {
  * Returns 0 on success or error code on failure.
  */
 int hv_create_ring_sysfs(struct vmbus_channel *channel,
-                        int (*hv_mmap_ring_buffer)(struct vmbus_channel 
*channel,
-                                                   struct vm_area_struct *vma))
+                        int (*hv_mmap_prepare_ring_buffer)(struct 
vmbus_channel *channel,
+                                                           struct vm_area_desc 
*desc))
 {
        struct kobject *kobj = &channel->kobj;
 
-       channel->mmap_ring_buffer = hv_mmap_ring_buffer;
+       channel->mmap_prepare_ring_buffer = hv_mmap_prepare_ring_buffer;
        channel->ring_sysfs_visible = true;
 
        return sysfs_update_group(kobj, &vmbus_chan_group);
@@ -2098,7 +2105,7 @@ int hv_remove_ring_sysfs(struct vmbus_channel *channel)
 
        channel->ring_sysfs_visible = false;
        ret = sysfs_update_group(kobj, &vmbus_chan_group);
-       channel->mmap_ring_buffer = NULL;
+       channel->mmap_prepare_ring_buffer = NULL;
        return ret;
 }
 EXPORT_SYMBOL_GPL(hv_remove_ring_sysfs);
diff --git a/drivers/uio/uio_hv_generic.c b/drivers/uio/uio_hv_generic.c
index 3f8e2e27697f..29ec2d15ada8 100644
--- a/drivers/uio/uio_hv_generic.c
+++ b/drivers/uio/uio_hv_generic.c
@@ -154,15 +154,16 @@ static void hv_uio_rescind(struct vmbus_channel *channel)
  * The ring buffer is allocated as contiguous memory by vmbus_open
  */
 static int
-hv_uio_ring_mmap(struct vmbus_channel *channel, struct vm_area_struct *vma)
+hv_uio_ring_mmap_prepare(struct vmbus_channel *channel, struct vm_area_desc 
*desc)
 {
        void *ring_buffer = page_address(channel->ringbuffer_page);
 
        if (channel->state != CHANNEL_OPENED_STATE)
                return -ENODEV;
 
-       return vm_iomap_memory(vma, virt_to_phys(ring_buffer),
-                              channel->ringbuffer_pagecount << PAGE_SHIFT);
+       mmap_action_simple_ioremap(desc, virt_to_phys(ring_buffer),
+                       channel->ringbuffer_pagecount << PAGE_SHIFT);
+       return 0;
 }
 
 /* Callback from VMBUS subsystem when new channel created. */
@@ -183,7 +184,7 @@ hv_uio_new_channel(struct vmbus_channel *new_sc)
        }
 
        set_channel_read_mode(new_sc, HV_CALL_ISR);
-       ret = hv_create_ring_sysfs(new_sc, hv_uio_ring_mmap);
+       ret = hv_create_ring_sysfs(new_sc, hv_uio_ring_mmap_prepare);
        if (ret) {
                dev_err(device, "sysfs create ring bin file failed; %d\n", ret);
                vmbus_close(new_sc);
@@ -366,7 +367,7 @@ hv_uio_probe(struct hv_device *dev,
         * or decoupled from uio_hv_generic probe. Userspace programs can make 
use of inotify
         * APIs to make sure that ring is created.
         */
-       hv_create_ring_sysfs(channel, hv_uio_ring_mmap);
+       hv_create_ring_sysfs(channel, hv_uio_ring_mmap_prepare);
 
        hv_set_drvdata(dev, pdata);
 
diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h
index dfc516c1c719..3a721b1853a4 100644
--- a/include/linux/hyperv.h
+++ b/include/linux/hyperv.h
@@ -1015,8 +1015,8 @@ struct vmbus_channel {
        /* The max size of a packet on this channel */
        u32 max_pkt_size;
 
-       /* function to mmap ring buffer memory to the channel's sysfs ring 
attribute */
-       int (*mmap_ring_buffer)(struct vmbus_channel *channel, struct 
vm_area_struct *vma);
+       /* function to mmap_prepare ring buffer memory to the channel's sysfs 
ring attribute */
+       int (*mmap_prepare_ring_buffer)(struct vmbus_channel *channel, struct 
vm_area_desc *desc);
 
        /* boolean to control visibility of sysfs for ring buffer */
        bool ring_sysfs_visible;
-- 
2.53.0


Reply via email to