VMCI: dma dg: set OS page size

Tell the device the page size used by the OS.

Reviewed-by: Vishnu Dasa <vdasa@vmware.com>
Signed-off-by: Jorgen Hansen <jhansen@vmware.com>
Link: https://lore.kernel.org/r/20220207102725.2742-5-jhansen@vmware.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/misc/vmw_vmci/vmci_guest.c b/drivers/misc/vmw_vmci/vmci_guest.c
index b93afe7f7119cd324c185214e2f718ea1507225c..ced187e7ac08bc503906b22703c66df0920d8409 100644 (file)
--- a/drivers/misc/vmw_vmci/vmci_guest.c
+++ b/drivers/misc/vmw_vmci/vmci_guest.c
@@ -578,6 +578,10 @@ static int vmci_guest_probe_device(struct pci_dev *pdev,
        /* Let the host know which capabilities we intend to use. */
        vmci_write_reg(vmci_dev, caps_in_use, VMCI_CAPS_ADDR);
 
+       /* Let the device know the size for pages passed down. */
+       if (caps_in_use & VMCI_CAPS_DMA_DATAGRAM)
+               vmci_write_reg(vmci_dev, PAGE_SHIFT, VMCI_GUEST_PAGE_SHIFT);
+
        /* Set up global device so that we can start sending datagrams */
        spin_lock_irq(&vmci_dev_spinlock);
        vmci_dev_g = vmci_dev;

diff --git a/include/linux/vmw_vmci_defs.h b/include/linux/vmw_vmci_defs.h
index 1ce2cffdc3ae1c805653a9817d49cabe50a562f5..4167779469fd1916b29bd0eb49bc1f54f90d0c3a 100644 (file)
--- a/include/linux/vmw_vmci_defs.h
+++ b/include/linux/vmw_vmci_defs.h
@@ -21,6 +21,7 @@
 #define VMCI_CAPS_ADDR          0x18
 #define VMCI_RESULT_LOW_ADDR    0x1c
 #define VMCI_RESULT_HIGH_ADDR   0x20
+#define VMCI_GUEST_PAGE_SHIFT   0x34
 
 /* Max number of devices. */
 #define VMCI_MAX_DEVICES 1