diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 0b3f6711d2f1a5a084ddab87e3ce27b5efae72fb..0072fabb1dd1d3d9f61d7d62a325f7ca997616ed 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -918,6 +918,10 @@ and is between 256 and 4096 characters. It is defined in the file
inttest= [IA64]
+ iomem= Disable strict checking of access to MMIO memory
+ strict regions from userspace.
+ relaxed
+
iommu= [x86]
off
force
diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c
index 544d724caeee010f149df1b26cf2c7baeab0e73f..88f1b10de3be712a33545b20292a45f7a1c43c50 100644
--- a/arch/x86/mm/init_32.c
+++ b/arch/x86/mm/init_32.c
@@ -328,6 +328,8 @@ int devmem_is_allowed(unsigned long pagenr)
{
if (pagenr <= 256)
return 1;
+ if (iomem_is_exclusive(pagenr << PAGE_SHIFT))
+ return 0;
if (!page_is_ram(pagenr))
return 1;
return 0;
diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c
index 54c437e96541f2764aaeb566793b092e2af2f219..23f68e77ad1fde95975c5b6e3cf163eb7850f305 100644
--- a/arch/x86/mm/init_64.c
+++ b/arch/x86/mm/init_64.c
@@ -888,6 +888,8 @@ int devmem_is_allowed(unsigned long pagenr)
{
if (pagenr <= 256)
return 1;
+ if (iomem_is_exclusive(pagenr << PAGE_SHIFT))
+ return 0;
if (!page_is_ram(pagenr))
return 1;
return 0;
diff --git a/drivers/net/e1000e/netdev.c b/drivers/net/e1000e/netdev.c
index d4639facd1bddcb72a200ada597d02fc284529e7..91817d0afcaf15a14db138a611160de81cd4fdf3 100644
--- a/drivers/net/e1000e/netdev.c
+++ b/drivers/net/e1000e/netdev.c
@@ -4807,7 +4807,7 @@ static int __devinit e1000_probe(struct pci_dev *pdev,
}
}
- err = pci_request_selected_regions(pdev,
+ err = pci_request_selected_regions_exclusive(pdev,
pci_select_bars(pdev, IORESOURCE_MEM),
e1000e_driver_name);
if (err)
diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c
index 388440e0d22228ac62ef39afd688dc1cc566abb6..d5cdccf27a695034c665b92ef54edcfb4fd70dab 100644
--- a/drivers/pci/pci-sysfs.c
+++ b/drivers/pci/pci-sysfs.c
@@ -620,6 +620,9 @@ pci_mmap_resource(struct kobject *kobj, struct bin_attribute *attr,
vma->vm_pgoff += start >> PAGE_SHIFT;
mmap_type = res->flags & IORESOURCE_MEM ? pci_mmap_mem : pci_mmap_io;
+ if (res->flags & IORESOURCE_MEM && iomem_is_exclusive(start))
+ return -EINVAL;
+
return pci_mmap_page_range(pdev, vma, mmap_type, write_combine);
}
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 2cfa41e367a78a63ead49905dbf2583f087e496e..47663dc0daf74ffc4d0e191c82d2b96b3750c6db 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -1395,7 +1395,8 @@ void pci_release_region(struct pci_dev *pdev, int bar)
* Returns 0 on success, or %EBUSY on error. A warning
* message is also printed on failure.
*/
-int pci_request_region(struct pci_dev *pdev, int bar, const char *res_name)
+static int __pci_request_region(struct pci_dev *pdev, int bar, const char *res_name,
+ int exclusive)
{
struct pci_devres *dr;
@@ -1408,8 +1409,9 @@ int pci_request_region(struct pci_dev *pdev, int bar, const char *res_name)
goto err_out;
}
else if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM) {
- if (!request_mem_region(pci_resource_start(pdev, bar),
- pci_resource_len(pdev, bar), res_name))
+ if (!__request_mem_region(pci_resource_start(pdev, bar),
+ pci_resource_len(pdev, bar), res_name,
+ exclusive))
goto err_out;
}
@@ -1427,6 +1429,47 @@ int pci_request_region(struct pci_dev *pdev, int bar, const char *res_name)
return -EBUSY;
}
+/**
+ * pci_request_region - Reserved PCI I/O and memory resource
+ * @pdev: PCI device whose resources are to be reserved
+ * @bar: BAR to be reserved
+ * @res_name: Name to be associated with resource.
+ *
+ * Mark the PCI region associated with PCI device @pdev BR @bar as
+ * being reserved by owner @res_name. Do not access any
+ * address inside the PCI regions unless this call returns
+ * successfully.
+ *
+ * Returns 0 on success, or %EBUSY on error. A warning
+ * message is also printed on failure.
+ */
+int pci_request_region(struct pci_dev *pdev, int bar, const char *res_name)
+{
+ return __pci_request_region(pdev, bar, res_name, 0);
+}
+
+/**
+ * pci_request_region_exclusive - Reserved PCI I/O and memory resource
+ * @pdev: PCI device whose resources are to be reserved
+ * @bar: BAR to be reserved
+ * @res_name: Name to be associated with resource.
+ *
+ * Mark the PCI region associated with PCI device @pdev BR @bar as
+ * being reserved by owner @res_name. Do not access any
+ * address inside the PCI regions unless this call returns
+ * successfully.
+ *
+ * Returns 0 on success, or %EBUSY on error. A warning
+ * message is also printed on failure.
+ *
+ * The key difference that _exclusive makes it that userspace is
+ * explicitly not allowed to map the resource via /dev/mem or
+ * sysfs.
+ */
+int pci_request_region_exclusive(struct pci_dev *pdev, int bar, const char *res_name)
+{
+ return __pci_request_region(pdev, bar, res_name, IORESOURCE_EXCLUSIVE);
+}
/**
* pci_release_selected_regions - Release selected PCI I/O and memory resources
* @pdev: PCI device whose resources were previously reserved
@@ -1444,20 +1487,14 @@ void pci_release_selected_regions(struct pci_dev *pdev, int bars)
pci_release_region(pdev, i);
}
-/**
- * pci_request_selected_regions - Reserve selected PCI I/O and memory resources
- * @pdev: PCI device whose resources are to be reserved
- * @bars: Bitmask of BARs to be requested
- * @res_name: Name to be associated with resource
- */
-int pci_request_selected_regions(struct pci_dev *pdev, int bars,
- const char *res_name)
+int __pci_request_selected_regions(struct pci_dev *pdev, int bars,
+ const char *res_name, int excl)
{
int i;
for (i = 0; i < 6; i++)
if (bars & (1 << i))
- if(pci_request_region(pdev, i, res_name))
+ if (__pci_request_region(pdev, i, res_name, excl))
goto err_out;
return 0;
@@ -1469,6 +1506,26 @@ int pci_request_selected_regions(struct pci_dev *pdev, int bars,
return -EBUSY;
}
+
+/**
+ * pci_request_selected_regions - Reserve selected PCI I/O and memory resources
+ * @pdev: PCI device whose resources are to be reserved
+ * @bars: Bitmask of BARs to be requested
+ * @res_name: Name to be associated with resource
+ */
+int pci_request_selected_regions(struct pci_dev *pdev, int bars,
+ const char *res_name)
+{
+ return __pci_request_selected_regions(pdev, bars, res_name, 0);
+}
+
+int pci_request_selected_regions_exclusive(struct pci_dev *pdev,
+ int bars, const char *res_name)
+{
+ return __pci_request_selected_regions(pdev, bars, res_name,
+ IORESOURCE_EXCLUSIVE);
+}
+
/**
* pci_release_regions - Release reserved PCI I/O and memory resources
* @pdev: PCI device whose resources were previously reserved by pci_request_regions
@@ -1501,6 +1558,29 @@ int pci_request_regions(struct pci_dev *pdev, const char *res_name)
return pci_request_selected_regions(pdev, ((1 << 6) - 1), res_name);
}
+/**
+ * pci_request_regions_exclusive - Reserved PCI I/O and memory resources
+ * @pdev: PCI device whose resources are to be reserved
+ * @res_name: Name to be associated with resource.
+ *
+ * Mark all PCI regions associated with PCI device @pdev as
+ * being reserved by owner @res_name. Do not access any
+ * address inside the PCI regions unless this call returns
+ * successfully.
+ *
+ * pci_request_regions_exclusive() will mark the region so that
+ * /dev/mem and the sysfs MMIO access will not be allowed.
+ *
+ * Returns 0 on success, or %EBUSY on error. A warning
+ * message is also printed on failure.
+ */
+int pci_request_regions_exclusive(struct pci_dev *pdev, const char *res_name)
+{
+ return pci_request_selected_regions_exclusive(pdev,
+ ((1 << 6) - 1), res_name);
+}
+
+
/**
* pci_set_master - enables bus-mastering for device dev
* @dev: the PCI device to enable
@@ -2149,10 +2229,13 @@ EXPORT_SYMBOL(pci_find_capability);
EXPORT_SYMBOL(pci_bus_find_capability);
EXPORT_SYMBOL(pci_release_regions);
EXPORT_SYMBOL(pci_request_regions);
+EXPORT_SYMBOL(pci_request_regions_exclusive);
EXPORT_SYMBOL(pci_release_region);
EXPORT_SYMBOL(pci_request_region);
+EXPORT_SYMBOL(pci_request_region_exclusive);
EXPORT_SYMBOL(pci_release_selected_regions);
EXPORT_SYMBOL(pci_request_selected_regions);
+EXPORT_SYMBOL(pci_request_selected_regions_exclusive);
EXPORT_SYMBOL(pci_set_master);
EXPORT_SYMBOL(pci_set_mwi);
EXPORT_SYMBOL(pci_try_set_mwi);
diff --git a/include/linux/ioport.h b/include/linux/ioport.h
index 041e95aac2bf317c40a3c68a45e223b322c80a26..f6bb2ca8e3ba44484ec2a9844af400f2d2014052 100644
--- a/include/linux/ioport.h
+++ b/include/linux/ioport.h
@@ -49,6 +49,7 @@ struct resource_list {
#define IORESOURCE_SIZEALIGN 0x00020000 /* size indicates alignment */
#define IORESOURCE_STARTALIGN 0x00040000 /* start field is alignment */
+#define IORESOURCE_EXCLUSIVE 0x08000000 /* Userland may not map this resource */
#define IORESOURCE_DISABLED 0x10000000
#define IORESOURCE_UNSET 0x20000000
#define IORESOURCE_AUTO 0x40000000
@@ -133,13 +134,16 @@ static inline unsigned long resource_type(struct resource *res)
}
/* Convenience shorthand with allocation */
-#define request_region(start,n,name) __request_region(&ioport_resource, (start), (n), (name))
-#define request_mem_region(start,n,name) __request_region(&iomem_resource, (start), (n), (name))
+#define request_region(start,n,name) __request_region(&ioport_resource, (start), (n), (name), 0)
+#define __request_mem_region(start,n,name, excl) __request_region(&iomem_resource, (start), (n), (name), excl)
+#define request_mem_region(start,n,name) __request_region(&iomem_resource, (start), (n), (name), 0)
+#define request_mem_region_exclusive(start,n,name) \
+ __request_region(&iomem_resource, (start), (n), (name), IORESOURCE_EXCLUSIVE)
#define rename_region(region, newname) do { (region)->name = (newname); } while (0)
extern struct resource * __request_region(struct resource *,
resource_size_t start,
- resource_size_t n, const char *name);
+ resource_size_t n, const char *name, int relaxed);
/* Compatibility cruft */
#define release_region(start,n) __release_region(&ioport_resource, (start), (n))
@@ -175,6 +179,7 @@ extern struct resource * __devm_request_region(struct device *dev,
extern void __devm_release_region(struct device *dev, struct resource *parent,
resource_size_t start, resource_size_t n);
extern int iomem_map_sanity_check(resource_size_t addr, unsigned long size);
+extern int iomem_is_exclusive(u64 addr);
#endif /* __ASSEMBLY__ */
#endif /* _LINUX_IOPORT_H */
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 59a3dc2059d3c818dee1c7b7a1c5e7790c459fbb..bfcb39ca88798b45619d72677262a8eb90340dfd 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -686,10 +686,13 @@ void pci_fixup_irqs(u8 (*)(struct pci_dev *, u8 *),
int (*)(struct pci_dev *, u8, u8));
#define HAVE_PCI_REQ_REGIONS 2
int __must_check pci_request_regions(struct pci_dev *, const char *);
+int __must_check pci_request_regions_exclusive(struct pci_dev *, const char *);
void pci_release_regions(struct pci_dev *);
int __must_check pci_request_region(struct pci_dev *, int, const char *);
+int __must_check pci_request_region_exclusive(struct pci_dev *, int, const char *);
void pci_release_region(struct pci_dev *, int);
int pci_request_selected_regions(struct pci_dev *, int, const char *);
+int pci_request_selected_regions_exclusive(struct pci_dev *, int, const char *);
void pci_release_selected_regions(struct pci_dev *, int);
/* drivers/pci/bus.c */
diff --git a/kernel/resource.c b/kernel/resource.c
index e633106b12f6ffe7f8da4fa48c6105582052e411..ca6a1536b205bf6b0271fa7d6fb92ea09f87b649 100644
--- a/kernel/resource.c
+++ b/kernel/resource.c
@@ -623,7 +623,7 @@ resource_size_t resource_alignment(struct resource *res)
*/
struct resource * __request_region(struct resource *parent,
resource_size_t start, resource_size_t n,
- const char *name)
+ const char *name, int flags)
{
struct resource *res = kzalloc(sizeof(*res), GFP_KERNEL);
@@ -634,6 +634,7 @@ struct resource * __request_region(struct resource *parent,
res->start = start;
res->end = start + n - 1;
res->flags = IORESOURCE_BUSY;
+ res->flags |= flags;
write_lock(&resource_lock);
@@ -679,7 +680,7 @@ int __check_region(struct resource *parent, resource_size_t start,
{
struct resource * res;
- res = __request_region(parent, start, n, "check-region");
+ res = __request_region(parent, start, n, "check-region", 0);
if (!res)
return -EBUSY;
@@ -776,7 +777,7 @@ struct resource * __devm_request_region(struct device *dev,
dr->start = start;
dr->n = n;
- res = __request_region(parent, start, n, name);
+ res = __request_region(parent, start, n, name, 0);
if (res)
devres_add(dev, dr);
else
@@ -876,3 +877,57 @@ int iomem_map_sanity_check(resource_size_t addr, unsigned long size)
return err;
}
+
+#ifdef CONFIG_STRICT_DEVMEM
+static int strict_iomem_checks = 1;
+#else
+static int strict_iomem_checks;
+#endif
+
+/*
+ * check if an address is reserved in the iomem resource tree
+ * returns 1 if reserved, 0 if not reserved.
+ */
+int iomem_is_exclusive(u64 addr)
+{
+ struct resource *p = &iomem_resource;
+ int err = 0;
+ loff_t l;
+ int size = PAGE_SIZE;
+
+ if (!strict_iomem_checks)
+ return 0;
+
+ addr = addr & PAGE_MASK;
+
+ read_lock(&resource_lock);
+ for (p = p->child; p ; p = r_next(NULL, p, &l)) {
+ /*
+ * We can probably skip the resources without
+ * IORESOURCE_IO attribute?
+ */
+ if (p->start >= addr + size)
+ break;
+ if (p->end < addr)
+ continue;
+ if (p->flags & IORESOURCE_BUSY &&
+ p->flags & IORESOURCE_EXCLUSIVE) {
+ err = 1;
+ break;
+ }
+ }
+ read_unlock(&resource_lock);
+
+ return err;
+}
+
+static int __init strict_iomem(char *str)
+{
+ if (strstr(str, "relaxed"))
+ strict_iomem_checks = 0;
+ if (strstr(str, "strict"))
+ strict_iomem_checks = 1;
+ return 1;
+}
+
+__setup("iomem=", strict_iomem);