Fedora kernel-2.6.17-1.2142_FC4 patched with stable patch-2.6.17.4-vs2.0.2-rc26.diff

[linux-2.6.git] / drivers / pci / access.c

diff --git a/drivers/pci/access.c b/drivers/pci/access.c
index 24a76de..ea16805 100644 (file)
--- a/drivers/pci/access.c
+++ b/drivers/pci/access.c
@@ -2,6 +2,8 @@
 #include <linux/module.h>
 #include <linux/ioport.h>
 
+#include "pci.h"
+
 /*
  * This interrupt-safe spinlock protects all accesses to PCI
  * configuration space.
@@ -60,3 +62,92 @@ EXPORT_SYMBOL(pci_bus_read_config_dword);
 EXPORT_SYMBOL(pci_bus_write_config_byte);
 EXPORT_SYMBOL(pci_bus_write_config_word);
 EXPORT_SYMBOL(pci_bus_write_config_dword);
+
+static u32 pci_user_cached_config(struct pci_dev *dev, int pos)
+{
+       u32 data;
+
+       data = dev->saved_config_space[pos/sizeof(dev->saved_config_space[0])];
+       data >>= (pos % sizeof(dev->saved_config_space[0])) * 8;
+       return data;
+}
+
+#define PCI_USER_READ_CONFIG(size,type)                                        \
+int pci_user_read_config_##size                                                \
+       (struct pci_dev *dev, int pos, type *val)                       \
+{                                                                      \
+       unsigned long flags;                                            \
+       int ret = 0;                                                    \
+       u32 data = -1;                                                  \
+       if (PCI_##size##_BAD) return PCIBIOS_BAD_REGISTER_NUMBER;       \
+       spin_lock_irqsave(&pci_lock, flags);                            \
+       if (likely(!dev->block_ucfg_access))                            \
+               ret = dev->bus->ops->read(dev->bus, dev->devfn,         \
+                                       pos, sizeof(type), &data);      \
+       else if (pos < sizeof(dev->saved_config_space))                 \
+               data = pci_user_cached_config(dev, pos);                \
+       spin_unlock_irqrestore(&pci_lock, flags);                       \
+       *val = (type)data;                                              \
+       return ret;                                                     \
+}
+
+#define PCI_USER_WRITE_CONFIG(size,type)                               \
+int pci_user_write_config_##size                                       \
+       (struct pci_dev *dev, int pos, type val)                        \
+{                                                                      \
+       unsigned long flags;                                            \
+       int ret = -EIO;                                                 \
+       if (PCI_##size##_BAD) return PCIBIOS_BAD_REGISTER_NUMBER;       \
+       spin_lock_irqsave(&pci_lock, flags);                            \
+       if (likely(!dev->block_ucfg_access))                            \
+               ret = dev->bus->ops->write(dev->bus, dev->devfn,        \
+                                       pos, sizeof(type), val);        \
+       spin_unlock_irqrestore(&pci_lock, flags);                       \
+       return ret;                                                     \
+}
+
+PCI_USER_READ_CONFIG(byte, u8)
+PCI_USER_READ_CONFIG(word, u16)
+PCI_USER_READ_CONFIG(dword, u32)
+PCI_USER_WRITE_CONFIG(byte, u8)
+PCI_USER_WRITE_CONFIG(word, u16)
+PCI_USER_WRITE_CONFIG(dword, u32)
+
+/**
+ * pci_block_user_cfg_access - Block userspace PCI config reads/writes
+ * @dev:       pci device struct
+ *
+ * This function blocks any userspace PCI config accesses from occurring.
+ * When blocked, any writes will be bit bucketed and reads will return the
+ * data saved using pci_save_state for the first 64 bytes of config
+ * space and return 0xff for all other config reads.
+ **/
+void pci_block_user_cfg_access(struct pci_dev *dev)
+{
+       unsigned long flags;
+
+       pci_save_state(dev);
+
+       /* spinlock to synchronize with anyone reading config space now */
+       spin_lock_irqsave(&pci_lock, flags);
+       dev->block_ucfg_access = 1;
+       spin_unlock_irqrestore(&pci_lock, flags);
+}
+EXPORT_SYMBOL_GPL(pci_block_user_cfg_access);
+
+/**
+ * pci_unblock_user_cfg_access - Unblock userspace PCI config reads/writes
+ * @dev:       pci device struct
+ *
+ * This function allows userspace PCI config accesses to resume.
+ **/
+void pci_unblock_user_cfg_access(struct pci_dev *dev)
+{
+       unsigned long flags;
+
+       /* spinlock to synchronize with anyone reading saved config space */
+       spin_lock_irqsave(&pci_lock, flags);
+       dev->block_ucfg_access = 0;
+       spin_unlock_irqrestore(&pci_lock, flags);
+}
+EXPORT_SYMBOL_GPL(pci_unblock_user_cfg_access);