ppc/ppc64: Fix pci mmap via sysfs

Hi !

This implement the change to /proc and sysfs PCI mmap functions that we discussed a while ago, that is adding an arch optional pci_resource_to_user() to allow munging on the exposed value of PCI resources to userland and thus hiding kernel internal values. It also implements using of that callback to sanitize exposed values on ppc an ppc64, thus fixing mmap of PCI devices via /proc and sysfs.

Index: linux-work/arch/ppc64/kernel/pci.c
===================================================================
@@ -351,9 +351,10 @@
 		*offset += hose->pci_mem_offset;
 		res_bit = IORESOURCE_MEM;
 	} else {
-		io_offset = (unsigned long)hose->io_base_virt;
+		io_offset = (unsigned long)hose->io_base_virt - pci_io_base;
 		*offset += io_offset;
 		res_bit = IORESOURCE_IO;
+		printk(" -> offset: %lx\n", *offset);
 	}
 
 	/*

@@ -373,12 +374,15 @@
 			continue;
 
 		/* In the range of this resource? */
+		printk(" r%d: %lx -> %lx\n", i, rp->start, rp->end);
 		if (*offset < (rp->start & PAGE_MASK) || *offset > rp->end)
 			continue;
 
 		/* found it! construct the final physical address */
-		if (mmap_state == pci_mmap_io)
-			*offset += hose->io_base_phys - io_offset;
+		if (mmap_state == pci_mmap_io) {
+		       	*offset += hose->io_base_phys - io_offset;
+			printk(" result: %lx\n", *offset);
+		}
 		return rp;
 	}
 

@@ -944,4 +948,22 @@
 }
 EXPORT_SYMBOL(pci_read_irq_line);
 
+void pci_resource_to_user(const struct pci_dev *dev, int bar,
+			  const struct resource *rsrc,
+			  u64 *start, u64 *end)
+{
+	struct pci_controller *hose = pci_bus_to_host(dev->bus);
+	unsigned long offset = 0;
+
+	if (hose == NULL)
+		return;
+
+	if (rsrc->flags & IORESOURCE_IO)
+		offset = pci_io_base - (unsigned long)hose->io_base_virt +
+			hose->io_base_phys;
+
+	*start = rsrc->start + offset;
+	*end = rsrc->end + offset;
+}
+
 #endif /* CONFIG_PPC_MULTIPLATFORM */

Index: linux-work/drivers/pci/pci-sysfs.c
===================================================================
@@ -60,15 +60,18 @@
 	char * str = buf;
 	int i;
 	int max = 7;
+	u64 start, end;
 
 	if (pci_dev->subordinate)
 		max = DEVICE_COUNT_RESOURCE;
 
 	for (i = 0; i < max; i++) {
-		str += sprintf(str,"0x%016lx 0x%016lx 0x%016lx\n",
-			       pci_resource_start(pci_dev,i),
-			       pci_resource_end(pci_dev,i),
-			       pci_resource_flags(pci_dev,i));
+		struct resource *res =  &pci_dev->resource[i];
+		pci_resource_to_user(pci_dev, i, res, &start, &end);
+		str += sprintf(str,"0x%016llx 0x%016llx 0x%016llx\n",
+			       (unsigned long long)start,
+			       (unsigned long long)end,
+			       (unsigned long long)res->flags);
 	}
 	return (str - buf);
 }

@@ -313,8 +316,21 @@
 						       struct device, kobj));
 	struct resource *res = (struct resource *)attr->private;
 	enum pci_mmap_state mmap_type;
+	u64 start, end;
+	int i;
 
-	vma->vm_pgoff += res->start >> PAGE_SHIFT;
+	for (i = 0; i < PCI_ROM_RESOURCE; i++)
+		if (res == &pdev->resource[i])
+			break;
+	if (i >= PCI_ROM_RESOURCE)
+		return -ENODEV;
+
+	/* pci_mmap_page_range() expects the same kind of entry as coming
+	 * from /proc/bus/pci/ which is a "user visible" value. If this is
+	 * different from the resource itself, arch will do necessary fixup.
+	 */
+	pci_resource_to_user(pdev, i, res, &start, &end);
+	vma->vm_pgoff += start >> PAGE_SHIFT;
 	mmap_type = res->flags & IORESOURCE_MEM ? pci_mmap_mem : pci_mmap_io;
 
 	return pci_mmap_page_range(pdev, vma, mmap_type, 0);

Index: linux-work/include/asm-ppc64/pci.h
===================================================================
@@ -135,6 +135,11 @@
 					 unsigned long offset,
 					 unsigned long size,
 					 pgprot_t prot);
+#define HAVE_ARCH_PCI_RESOURCE_TO_USER
+extern void pci_resource_to_user(const struct pci_dev *dev, int bar,
+				 const struct resource *rsrc,
+				 u64 *start, u64 *end);
+
 
 
 #endif	/* __KERNEL__ */

Index: linux-work/drivers/pci/proc.c
===================================================================
@@ -355,14 +355,20 @@
 			dev->device,
 			dev->irq);
 	/* Here should be 7 and not PCI_NUM_RESOURCES as we need to preserve compatibility */
-	for(i=0; i<7; i++)
+	for(i=0; i<7; i++) {
+		u64 start, end;
+		pci_resource_to_user(dev, i, &dev->resource[i], &start, &end);
 		seq_printf(m, LONG_FORMAT,
-			dev->resource[i].start |
+			((unsigned long)start) |
 			(dev->resource[i].flags & PCI_REGION_FLAG_MASK));
-	for(i=0; i<7; i++)
+	}
+	for(i=0; i<7; i++) {
+		u64 start, end;
+		pci_resource_to_user(dev, i, &dev->resource[i], &start, &end);
 		seq_printf(m, LONG_FORMAT,
 			dev->resource[i].start < dev->resource[i].end ?
-			dev->resource[i].end - dev->resource[i].start + 1 : 0);
+			(unsigned long)(end - start) + 1 : 0);
+	}
 	seq_putc(m, '\t');
 	if (drv)
 		seq_printf(m, "%s", drv->name);

Index: linux-work/drivers/pci/pci.c
===================================================================
@@ -759,7 +759,7 @@
 	return 0;
 }
 #endif
-     
+
 static int __devinit pci_init(void)
 {
 	struct pci_dev *dev = NULL;

Index: linux-work/include/linux/pci.h
===================================================================
@@ -1016,6 +1016,21 @@
 #define pci_pretty_name(dev) ""
 #endif
 
+
+/* Some archs don't want to expose struct resource to userland as-is
+ * in sysfs and /proc
+ */
+#ifndef HAVE_ARCH_PCI_RESOURCE_TO_USER
+static void pci_resource_to_user(const struct pci_dev *dev, int bar,
+				 const struct resource *rsrc,
+				 u64 *start, u64 *end)
+{
+	*start = rsrc->start;
+	*end = rsrc->end;
+}
+#endif /* HAVE_ARCH_PCI_RESOURCE_TO_USER */
+
+
 /*
  *  The world is not perfect and supplies us with broken PCI devices.
  *  For at least a part of these bugs we need a work-around, so both

Index: linux-work/include/asm-ppc/pci.h
===================================================================
@@ -103,6 +103,12 @@
 					 unsigned long size,
 					 pgprot_t prot);
 
+#define HAVE_ARCH_PCI_RESOURCE_TO_USER
+extern void pci_resource_to_user(const struct pci_dev *dev, int bar,
+				 const struct resource *rsrc,
+				 u64 *start, u64 *end);
+
+
 #endif	/* __KERNEL__ */
 
 #endif /* __PPC_PCI_H */

Index: linux-work/arch/ppc/kernel/pci.c
===================================================================
@@ -1495,7 +1495,7 @@
 		*offset += hose->pci_mem_offset;
 		res_bit = IORESOURCE_MEM;
 	} else {
-		io_offset = (unsigned long)hose->io_base_virt;
+		io_offset = hose->io_base_virt - ___IO_BASE;
 		*offset += io_offset;
 		res_bit = IORESOURCE_IO;
 	}

@@ -1522,7 +1522,7 @@
 
 		/* found it! construct the final physical address */
 		if (mmap_state == pci_mmap_io)
-			*offset += hose->io_base_phys - _IO_BASE;
+			*offset += hose->io_base_phys - io_offset;
 		return rp;
 	}
 

@@ -1739,6 +1739,23 @@
 	return result;
 }
 
+void pci_resource_to_user(const struct pci_dev *dev, int bar,
+			  const struct resource *rsrc,
+			  u64 *start, u64 *end)
+{
+	struct pci_controller *hose = pci_bus_to_hose(dev->bus->number);
+	unsigned long offset = 0;
+
+	if (hose == NULL)
+		return;
+
+	if (rsrc->flags & IORESOURCE_IO)
+		offset = ___IO_BASE - hose->io_base_virt + hose->io_base_phys;
+
+	*start = rsrc->start + offset;
+	*end = rsrc->end + offset;
+}
+
 void __init
 pci_init_resource(struct resource *res, unsigned long start, unsigned long end,
 		  int flags, char *name)

One quilt ref later ... :)

Hi !

This implement the change to /proc and sysfs PCI mmap functions that we discussed a while ago, that is adding an arch optional pci_resource_to_user() to allow munging on the exposed value of PCI resources to userland and thus hiding kernel internal values. It also implements using of that callback to sanitize exposed values on ppc an ppc64, thus fixing mmap of PCI devices via /proc and sysfs.

Index: linux-work/arch/ppc64/kernel/pci.c
===================================================================
--- linux-work.orig/arch/ppc64/kernel/pci.c 2005-06-25
09:22:56.000000000 +1000
+++ linux-work/arch/ppc64/kernel/pci.c 2005-06-27 12:09:58.000000000
+1000
@@ -351,7 +351,7 @@
*offset += hose->pci_mem_offset;
res_bit = IORESOURCE_MEM;
} else {
- io_offset = (unsigned long)hose->io_base_virt;
+ io_offset = (unsigned long)hose->io_base_virt - pci_io_base;
*offset += io_offset;
res_bit = IORESOURCE_IO;
}
@@ -378,7 +378,7 @@

/* found it! construct the final physical address */ if (mmap_state == pci_mmap_io)
- *offset += hose->io_base_phys - io_offset;
+ *offset += hose->io_base_phys - io_offset;
return rp;
}

@@ -416,9 +416,6 @@
else
prot |= _PAGE_GUARDED;

- printk("PCI map for %s:%lx, prot: %lx\n", pci_name(dev), rp->start,
- prot);
-
return __pgprot(prot);
}

@@ -944,4 +941,22 @@
}
EXPORT_SYMBOL(pci_read_irq_line);

+void pci_resource_to_user(const struct pci_dev *dev, int bar,
+ const struct resource *rsrc,
+ u64 *start, u64 *end)
+{
+ struct pci_controller *hose = pci_bus_to_host(dev->bus);
+ unsigned long offset = 0;
+
+ if (hose == NULL)
+ return;
+
+ if (rsrc->flags & IORESOURCE_IO)
+ offset = pci_io_base - (unsigned long)hose->io_base_virt +
+ hose->io_base_phys;
+
+ *start = rsrc->start + offset;
+ *end = rsrc->end + offset;
+}
+
#endif /* CONFIG_PPC_MULTIPLATFORM */
Index: linux-work/drivers/pci/pci-sysfs.c
===================================================================
--- linux-work.orig/drivers/pci/pci-sysfs.c 2005-06-25
09:22:57.000000000 +1000
+++ linux-work/drivers/pci/pci-sysfs.c 2005-06-27 11:28:21.000000000
+1000
@@ -60,15 +60,18 @@
char * str = buf;
int i;
int max = 7;
+ u64 start, end;

if (pci_dev->subordinate)
max = DEVICE_COUNT_RESOURCE;

for (i = 0; i < max; i++) {
- str += sprintf(str,"0x%016lx 0x%016lx 0x%016lx\n",

-			       pci_resource_start(pci_dev,i),
-			       pci_resource_end(pci_dev,i),
-			       pci_resource_flags(pci_dev,i));
+		struct resource *res =  &pci_dev->resource[i];
+		pci_resource_to_user(pci_dev, i, res, &start, &end);
+		str += sprintf(str,"0x%016llx 0x%016llx 0x%016llx\n",
+			       (unsigned long long)start,
+			       (unsigned long long)end,
+			       (unsigned long long)res->flags);

}
return (str - buf);
}
@@ -313,8 +316,21 @@
struct device, kobj));
struct resource *res = (struct resource *)attr->private; enum pci_mmap_state mmap_type;
+ u64 start, end;
+ int i;

- vma->vm_pgoff += res->start >> PAGE_SHIFT;
+ for (i = 0; i < PCI_ROM_RESOURCE; i++)
+ if (res == &pdev->resource[i])
+ break;
+ if (i >= PCI_ROM_RESOURCE)
+ return -ENODEV;
+
+ /* pci_mmap_page_range() expects the same kind of entry as coming
+ * from /proc/bus/pci/ which is a "user visible" value. If this is
+ * different from the resource itself, arch will do necessary fixup.
+ */
+ pci_resource_to_user(pdev, i, res, &start, &end);
+ vma->vm_pgoff += start >> PAGE_SHIFT;
mmap_type = res->flags & IORESOURCE_MEM ? pci_mmap_mem : pci_mmap_io;

return pci_mmap_page_range(pdev, vma, mmap_type, 0);
Index: linux-work/include/asm-ppc64/pci.h
===================================================================
--- linux-work.orig/include/asm-ppc64/pci.h 2005-05-02
10:50:01.000000000 +1000
+++ linux-work/include/asm-ppc64/pci.h 2005-06-27 11:28:21.000000000
+1000
@@ -135,6 +135,11 @@
unsigned long offset, unsigned long size, pgprot_t prot);
+#define HAVE_ARCH_PCI_RESOURCE_TO_USER
+extern void pci_resource_to_user(const struct pci_dev *dev, int bar,
+ const struct resource *rsrc,
+ u64 *start, u64 *end);
+

#endif /* __KERNEL__ */
Index: linux-work/drivers/pci/proc.c
===================================================================
--- linux-work.orig/drivers/pci/proc.c 2005-05-05 15:56:37.000000000
+1000
+++ linux-work/drivers/pci/proc.c 2005-06-27 11:28:21.000000000 +1000
@@ -355,14 +355,20 @@
dev->device,
dev->irq);
/* Here should be 7 and not PCI_NUM_RESOURCES as we need to preserve
compatibility */
- for(i=0; i<7; i++)
+ for(i=0; i<7; i++) {
+ u64 start, end;
+ pci_resource_to_user(dev, i, &dev->resource[i], &start, &end);
seq_printf(m, LONG_FORMAT,
- dev->resource[i].start |
+ ((unsigned long)start) |
(dev->resource[i].flags & PCI_REGION_FLAG_MASK));
- for(i=0; i<7; i++)
+ }
+ for(i=0; i<7; i++) {
+ u64 start, end;
+ pci_resource_to_user(dev, i, &dev->resource[i], &start, &end);
seq_printf(m, LONG_FORMAT,
dev->resource[i].start < dev->resource[i].end ?
- dev->resource[i].end - dev->resource[i].start + 1 : 0);
+ (unsigned long)(end - start) + 1 : 0);
+ }
seq_putc(m, '\t');
if (drv)
seq_printf(m, "%s", drv->name);
Index: linux-work/drivers/pci/pci.c
===================================================================
--- linux-work.orig/drivers/pci/pci.c 2005-05-05 15:56:37.000000000
+1000
+++ linux-work/drivers/pci/pci.c 2005-06-27 11:28:21.000000000 +1000
@@ -759,7 +759,7 @@
return 0;
}
#endif
-
+
static int __devinit pci_init(void)
{
struct pci_dev *dev = NULL;
Index: linux-work/include/linux/pci.h
===================================================================
--- linux-work.orig/include/linux/pci.h 2005-05-05 15:56:38.000000000
+1000
+++ linux-work/include/linux/pci.h 2005-06-27 11:28:21.000000000 +1000
@@ -1016,6 +1016,21 @@
#define pci_pretty_name(dev) ""
#endif

+
+/* Some archs don't want to expose struct resource to userland as-is
+ * in sysfs and /proc
+ */
+#ifndef HAVE_ARCH_PCI_RESOURCE_TO_USER
+static void pci_resource_to_user(const struct pci_dev *dev, int bar,
+ const struct resource *rsrc,
+ u64 *start, u64 *end)
+{
+ *start = rsrc->start;
+ *end = rsrc->end;
+}
+#endif /* HAVE_ARCH_PCI_RESOURCE_TO_USER */
+
+
/*
* The world is not perfect and supplies us with broken PCI devices.
* For at least a part of these bugs we need a work-around, so both
Index: linux-work/include/asm-ppc/pci.h
===================================================================
--- linux-work.orig/include/asm-ppc/pci.h 2005-05-02 10:49:57.000000000
+1000
+++ linux-work/include/asm-ppc/pci.h 2005-06-27 11:28:21.000000000 +1000
@@ -103,6 +103,12 @@
unsigned long size, pgprot_t prot);

+#define HAVE_ARCH_PCI_RESOURCE_TO_USER
+extern void pci_resource_to_user(const struct pci_dev *dev, int bar,
+ const struct resource *rsrc,
+ u64 *start, u64 *end);
+
+
#endif /* __KERNEL__ */

#endif /* __PPC_PCI_H */
Index: linux-work/arch/ppc/kernel/pci.c
===================================================================
--- linux-work.orig/arch/ppc/kernel/pci.c 2005-06-25 09:22:56.000000000
+1000
+++ linux-work/arch/ppc/kernel/pci.c 2005-06-27 12:09:30.000000000 +1000
@@ -1495,7 +1495,7 @@
*offset += hose->pci_mem_offset;
res_bit = IORESOURCE_MEM;
} else {
- io_offset = (unsigned long)hose->io_base_virt;
+ io_offset = hose->io_base_virt - ___IO_BASE;
*offset += io_offset;
res_bit = IORESOURCE_IO;
}
@@ -1522,7 +1522,7 @@

/* found it! construct the final physical address */ if (mmap_state == pci_mmap_io)
- *offset += hose->io_base_phys - _IO_BASE;
+ *offset += hose->io_base_phys - io_offset;
return rp;
}

@@ -1560,9 +1560,6 @@
else
prot |= _PAGE_GUARDED;

- printk("PCI map for %s:%lx, prot: %lx\n", pci_name(dev), rp->start,
- prot);
-
return __pgprot(prot);
}

@@ -1739,6 +1736,23 @@
return result;
}

+void pci_resource_to_user(const struct pci_dev *dev, int bar,
+ const struct resource *rsrc,
+ u64 *start, u64 *end)
+{
+ struct pci_controller *hose = pci_bus_to_hose(dev->bus->number);
+ unsigned long offset = 0;
+
+ if (hose == NULL)
+ return;
+
+ if (rsrc->flags & IORESOURCE_IO)
+ offset = ___IO_BASE - hose->io_base_virt + hose->io_base_phys;
+
+ *start = rsrc->start + offset;
+ *end = rsrc->end + offset;
+}
+
void __init
pci_init_resource(struct resource *res, unsigned long start, unsigned
long end,
int flags, char *name)

Hm, did I just send the right one to Linus?

thanks,

greg k-h

I'll check & send any additional fix that may be necessary (I just got noticed that it breaks iSeries ... :)

Ben.

This one looks better. :) Thanks for fixing this up.

Please document it in sysfs-pci.txt too (I guess we don't have a similar document for /proc/bus/pci unfortunately) so that people won't miss it when they implement /proc/bus/pci and sysfs PCI mmap support in the future.

Thanks,
Jesse