diff --git a/drivers/pci/access.c b/drivers/pci/access.c
index 24a76de..2a42add 100644
--- a/drivers/pci/access.c
+++ b/drivers/pci/access.c
@@ -60,3 +60,92 @@
 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);
diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c
index 2898830..965a593 100644
--- a/drivers/pci/pci-sysfs.c
+++ b/drivers/pci/pci-sysfs.c
@@ -130,7 +130,7 @@
 
 	if ((off & 1) && size) {
 		u8 val;
-		pci_read_config_byte(dev, off, &val);
+		pci_user_read_config_byte(dev, off, &val);
 		data[off - init_off] = val;
 		off++;
 		size--;
@@ -138,7 +138,7 @@
 
 	if ((off & 3) && size > 2) {
 		u16 val;
-		pci_read_config_word(dev, off, &val);
+		pci_user_read_config_word(dev, off, &val);
 		data[off - init_off] = val & 0xff;
 		data[off - init_off + 1] = (val >> 8) & 0xff;
 		off += 2;
@@ -147,7 +147,7 @@
 
 	while (size > 3) {
 		u32 val;
-		pci_read_config_dword(dev, off, &val);
+		pci_user_read_config_dword(dev, off, &val);
 		data[off - init_off] = val & 0xff;
 		data[off - init_off + 1] = (val >> 8) & 0xff;
 		data[off - init_off + 2] = (val >> 16) & 0xff;
@@ -158,7 +158,7 @@
 
 	if (size >= 2) {
 		u16 val;
-		pci_read_config_word(dev, off, &val);
+		pci_user_read_config_word(dev, off, &val);
 		data[off - init_off] = val & 0xff;
 		data[off - init_off + 1] = (val >> 8) & 0xff;
 		off += 2;
@@ -167,7 +167,7 @@
 
 	if (size > 0) {
 		u8 val;
-		pci_read_config_byte(dev, off, &val);
+		pci_user_read_config_byte(dev, off, &val);
 		data[off - init_off] = val;
 		off++;
 		--size;
@@ -192,7 +192,7 @@
 	}
 	
 	if ((off & 1) && size) {
-		pci_write_config_byte(dev, off, data[off - init_off]);
+		pci_user_write_config_byte(dev, off, data[off - init_off]);
 		off++;
 		size--;
 	}
@@ -200,7 +200,7 @@
 	if ((off & 3) && size > 2) {
 		u16 val = data[off - init_off];
 		val |= (u16) data[off - init_off + 1] << 8;
-                pci_write_config_word(dev, off, val);
+                pci_user_write_config_word(dev, off, val);
                 off += 2;
                 size -= 2;
         }
@@ -210,7 +210,7 @@
 		val |= (u32) data[off - init_off + 1] << 8;
 		val |= (u32) data[off - init_off + 2] << 16;
 		val |= (u32) data[off - init_off + 3] << 24;
-		pci_write_config_dword(dev, off, val);
+		pci_user_write_config_dword(dev, off, val);
 		off += 4;
 		size -= 4;
 	}
@@ -218,13 +218,13 @@
 	if (size >= 2) {
 		u16 val = data[off - init_off];
 		val |= (u16) data[off - init_off + 1] << 8;
-		pci_write_config_word(dev, off, val);
+		pci_user_write_config_word(dev, off, val);
 		off += 2;
 		size -= 2;
 	}
 
 	if (size) {
-		pci_write_config_byte(dev, off, data[off - init_off]);
+		pci_user_write_config_byte(dev, off, data[off - init_off]);
 		off++;
 		--size;
 	}
diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index d3f3dd4..6527b36 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -15,6 +15,13 @@
 extern int (*platform_pci_choose_state)(struct pci_dev *dev, pm_message_t state);
 extern int (*platform_pci_set_power_state)(struct pci_dev *dev, pci_power_t state);
 
+extern int pci_user_read_config_byte(struct pci_dev *dev, int where, u8 *val);
+extern int pci_user_read_config_word(struct pci_dev *dev, int where, u16 *val);
+extern int pci_user_read_config_dword(struct pci_dev *dev, int where, u32 *val);
+extern int pci_user_write_config_byte(struct pci_dev *dev, int where, u8 val);
+extern int pci_user_write_config_word(struct pci_dev *dev, int where, u16 val);
+extern int pci_user_write_config_dword(struct pci_dev *dev, int where, u32 val);
+
 /* PCI /proc functions */
 #ifdef CONFIG_PROC_FS
 extern int pci_proc_attach_device(struct pci_dev *dev);
diff --git a/drivers/pci/proc.c b/drivers/pci/proc.c
index 9613f66..9eb4657 100644
--- a/drivers/pci/proc.c
+++ b/drivers/pci/proc.c
@@ -80,7 +80,7 @@
 
 	if ((pos & 1) && cnt) {
 		unsigned char val;
-		pci_read_config_byte(dev, pos, &val);
+		pci_user_read_config_byte(dev, pos, &val);
 		__put_user(val, buf);
 		buf++;
 		pos++;
@@ -89,7 +89,7 @@
 
 	if ((pos & 3) && cnt > 2) {
 		unsigned short val;
-		pci_read_config_word(dev, pos, &val);
+		pci_user_read_config_word(dev, pos, &val);
 		__put_user(cpu_to_le16(val), (unsigned short __user *) buf);
 		buf += 2;
 		pos += 2;
@@ -98,7 +98,7 @@
 
 	while (cnt >= 4) {
 		unsigned int val;
-		pci_read_config_dword(dev, pos, &val);
+		pci_user_read_config_dword(dev, pos, &val);
 		__put_user(cpu_to_le32(val), (unsigned int __user *) buf);
 		buf += 4;
 		pos += 4;
@@ -107,7 +107,7 @@
 
 	if (cnt >= 2) {
 		unsigned short val;
-		pci_read_config_word(dev, pos, &val);
+		pci_user_read_config_word(dev, pos, &val);
 		__put_user(cpu_to_le16(val), (unsigned short __user *) buf);
 		buf += 2;
 		pos += 2;
@@ -116,7 +116,7 @@
 
 	if (cnt) {
 		unsigned char val;
-		pci_read_config_byte(dev, pos, &val);
+		pci_user_read_config_byte(dev, pos, &val);
 		__put_user(val, buf);
 		buf++;
 		pos++;
@@ -151,7 +151,7 @@
 	if ((pos & 1) && cnt) {
 		unsigned char val;
 		__get_user(val, buf);
-		pci_write_config_byte(dev, pos, val);
+		pci_user_write_config_byte(dev, pos, val);
 		buf++;
 		pos++;
 		cnt--;
@@ -160,7 +160,7 @@
 	if ((pos & 3) && cnt > 2) {
 		unsigned short val;
 		__get_user(val, (unsigned short __user *) buf);
-		pci_write_config_word(dev, pos, le16_to_cpu(val));
+		pci_user_write_config_word(dev, pos, le16_to_cpu(val));
 		buf += 2;
 		pos += 2;
 		cnt -= 2;
@@ -169,7 +169,7 @@
 	while (cnt >= 4) {
 		unsigned int val;
 		__get_user(val, (unsigned int __user *) buf);
-		pci_write_config_dword(dev, pos, le32_to_cpu(val));
+		pci_user_write_config_dword(dev, pos, le32_to_cpu(val));
 		buf += 4;
 		pos += 4;
 		cnt -= 4;
@@ -178,7 +178,7 @@
 	if (cnt >= 2) {
 		unsigned short val;
 		__get_user(val, (unsigned short __user *) buf);
-		pci_write_config_word(dev, pos, le16_to_cpu(val));
+		pci_user_write_config_word(dev, pos, le16_to_cpu(val));
 		buf += 2;
 		pos += 2;
 		cnt -= 2;
@@ -187,7 +187,7 @@
 	if (cnt) {
 		unsigned char val;
 		__get_user(val, buf);
-		pci_write_config_byte(dev, pos, val);
+		pci_user_write_config_byte(dev, pos, val);
 		buf++;
 		pos++;
 		cnt--;
@@ -484,10 +484,10 @@
 
 	drv = pci_dev_driver(dev);
 
-	pci_read_config_dword(dev, PCI_CLASS_REVISION, &class_rev);
-	pci_read_config_byte (dev, PCI_LATENCY_TIMER, &latency);
-	pci_read_config_byte (dev, PCI_MIN_GNT, &min_gnt);
-	pci_read_config_byte (dev, PCI_MAX_LAT, &max_lat);
+	pci_user_read_config_dword(dev, PCI_CLASS_REVISION, &class_rev);
+	pci_user_read_config_byte (dev, PCI_LATENCY_TIMER, &latency);
+	pci_user_read_config_byte (dev, PCI_MIN_GNT, &min_gnt);
+	pci_user_read_config_byte (dev, PCI_MAX_LAT, &max_lat);
 	seq_printf(m, "  Bus %2d, device %3d, function %2d:\n",
 	       dev->bus->number, PCI_SLOT(dev->devfn), PCI_FUNC(dev->devfn));
 	seq_printf(m, "    Class %04x", class_rev >> 16);
diff --git a/drivers/pci/syscall.c b/drivers/pci/syscall.c
index c071790..87fafc0 100644
--- a/drivers/pci/syscall.c
+++ b/drivers/pci/syscall.c
@@ -13,7 +13,7 @@
 #include <linux/smp_lock.h>
 #include <linux/syscalls.h>
 #include <asm/uaccess.h>
-
+#include "pci.h"
 
 asmlinkage long
 sys_pciconfig_read(unsigned long bus, unsigned long dfn,
@@ -38,13 +38,13 @@
 	lock_kernel();
 	switch (len) {
 	case 1:
-		cfg_ret = pci_read_config_byte(dev, off, &byte);
+		cfg_ret = pci_user_read_config_byte(dev, off, &byte);
 		break;
 	case 2:
-		cfg_ret = pci_read_config_word(dev, off, &word);
+		cfg_ret = pci_user_read_config_word(dev, off, &word);
 		break;
 	case 4:
-		cfg_ret = pci_read_config_dword(dev, off, &dword);
+		cfg_ret = pci_user_read_config_dword(dev, off, &dword);
 		break;
 	default:
 		err = -EINVAL;
@@ -112,7 +112,7 @@
 		err = get_user(byte, (u8 __user *)buf);
 		if (err)
 			break;
-		err = pci_write_config_byte(dev, off, byte);
+		err = pci_user_write_config_byte(dev, off, byte);
 		if (err != PCIBIOS_SUCCESSFUL)
 			err = -EIO;
 		break;
@@ -121,7 +121,7 @@
 		err = get_user(word, (u16 __user *)buf);
 		if (err)
 			break;
-		err = pci_write_config_word(dev, off, word);
+		err = pci_user_write_config_word(dev, off, word);
 		if (err != PCIBIOS_SUCCESSFUL)
 			err = -EIO;
 		break;
@@ -130,7 +130,7 @@
 		err = get_user(dword, (u32 __user *)buf);
 		if (err)
 			break;
-		err = pci_write_config_dword(dev, off, dword);
+		err = pci_user_write_config_dword(dev, off, dword);
 		if (err != PCIBIOS_SUCCESSFUL)
 			err = -EIO;
 		break;
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 7349058..3596ac9 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -132,6 +132,7 @@
 	unsigned int	is_enabled:1;	/* pci_enable_device has been called */
 	unsigned int	is_busmaster:1; /* device is busmaster */
 	unsigned int	no_msi:1;	/* device may not use msi */
+	unsigned int	block_ucfg_access:1;	/* userspace config space access is blocked */
 
 	u32		saved_config_space[16]; /* config space saved at suspend time */
 	struct bin_attribute *rom_attr; /* attribute descriptor for sysfs ROM entry */
@@ -490,6 +491,9 @@
 extern void msi_remove_pci_irq_vectors(struct pci_dev *dev);
 #endif
 
+extern void pci_block_user_cfg_access(struct pci_dev *dev);
+extern void pci_unblock_user_cfg_access(struct pci_dev *dev);
+
 /*
  * PCI domain support.  Sometimes called PCI segment (eg by ACPI),
  * a PCI domain is defined to be a set of PCI busses which share
@@ -560,6 +564,9 @@
 
 #define pci_dma_burst_advice(pdev, strat, strategy_parameter) do { } while (0)
 
+static inline void pci_block_user_cfg_access(struct pci_dev *dev) { }
+static inline void pci_unblock_user_cfg_access(struct pci_dev *dev) { }
+
 #endif /* CONFIG_PCI */
 
 /* Include architecture-dependent settings and functions */