Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / drivers / pci / syscall.c

diff --git a/kernel/drivers/pci/syscall.c b/kernel/drivers/pci/syscall.c
new file mode 100644 (file)
index 0000000..b91c4da
--- /dev/null
+++ b/kernel/drivers/pci/syscall.c
@@ -0,0 +1,136 @@
+/*
+ *     pci_syscall.c
+ *
+ * For architectures where we want to allow direct access
+ * to the PCI config stuff - it would probably be preferable
+ * on PCs too, but there people just do it by hand with the
+ * magic northbridge registers..
+ */
+
+#include <linux/errno.h>
+#include <linux/pci.h>
+#include <linux/syscalls.h>
+#include <asm/uaccess.h>
+#include "pci.h"
+
+SYSCALL_DEFINE5(pciconfig_read, unsigned long, bus, unsigned long, dfn,
+               unsigned long, off, unsigned long, len, void __user *, buf)
+{
+       struct pci_dev *dev;
+       u8 byte;
+       u16 word;
+       u32 dword;
+       long err;
+       long cfg_ret;
+
+       if (!capable(CAP_SYS_ADMIN))
+               return -EPERM;
+
+       err = -ENODEV;
+       dev = pci_get_bus_and_slot(bus, dfn);
+       if (!dev)
+               goto error;
+
+       switch (len) {
+       case 1:
+               cfg_ret = pci_user_read_config_byte(dev, off, &byte);
+               break;
+       case 2:
+               cfg_ret = pci_user_read_config_word(dev, off, &word);
+               break;
+       case 4:
+               cfg_ret = pci_user_read_config_dword(dev, off, &dword);
+               break;
+       default:
+               err = -EINVAL;
+               goto error;
+       }
+
+       err = -EIO;
+       if (cfg_ret != PCIBIOS_SUCCESSFUL)
+               goto error;
+
+       switch (len) {
+       case 1:
+               err = put_user(byte, (unsigned char __user *)buf);
+               break;
+       case 2:
+               err = put_user(word, (unsigned short __user *)buf);
+               break;
+       case 4:
+               err = put_user(dword, (unsigned int __user *)buf);
+               break;
+       }
+       pci_dev_put(dev);
+       return err;
+
+error:
+       /* ??? XFree86 doesn't even check the return value.  They
+          just look for 0xffffffff in the output, since that's what
+          they get instead of a machine check on x86.  */
+       switch (len) {
+       case 1:
+               put_user(-1, (unsigned char __user *)buf);
+               break;
+       case 2:
+               put_user(-1, (unsigned short __user *)buf);
+               break;
+       case 4:
+               put_user(-1, (unsigned int __user *)buf);
+               break;
+       }
+       pci_dev_put(dev);
+       return err;
+}
+
+SYSCALL_DEFINE5(pciconfig_write, unsigned long, bus, unsigned long, dfn,
+               unsigned long, off, unsigned long, len, void __user *, buf)
+{
+       struct pci_dev *dev;
+       u8 byte;
+       u16 word;
+       u32 dword;
+       int err = 0;
+
+       if (!capable(CAP_SYS_ADMIN))
+               return -EPERM;
+
+       dev = pci_get_bus_and_slot(bus, dfn);
+       if (!dev)
+               return -ENODEV;
+
+       switch (len) {
+       case 1:
+               err = get_user(byte, (u8 __user *)buf);
+               if (err)
+                       break;
+               err = pci_user_write_config_byte(dev, off, byte);
+               if (err != PCIBIOS_SUCCESSFUL)
+                       err = -EIO;
+               break;
+
+       case 2:
+               err = get_user(word, (u16 __user *)buf);
+               if (err)
+                       break;
+               err = pci_user_write_config_word(dev, off, word);
+               if (err != PCIBIOS_SUCCESSFUL)
+                       err = -EIO;
+               break;
+
+       case 4:
+               err = get_user(dword, (u32 __user *)buf);
+               if (err)
+                       break;
+               err = pci_user_write_config_dword(dev, off, dword);
+               if (err != PCIBIOS_SUCCESSFUL)
+                       err = -EIO;
+               break;
+
+       default:
+               err = -EINVAL;
+               break;
+       }
+       pci_dev_put(dev);
+       return err;
+}