x86: PAT export resource_wc in pci sysfs
For the ranges with IORESOURCE_PREFETCH, export a new resource_wc interface in
pci /sysfs along with resource (which is uncached).
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c
index 271d41c..9ec7d39 100644
--- a/drivers/pci/pci-sysfs.c
+++ b/drivers/pci/pci-sysfs.c
@@ -489,13 +489,14 @@
* @kobj: kobject for mapping
* @attr: struct bin_attribute for the file being mapped
* @vma: struct vm_area_struct passed into the mmap
+ * @write_combine: 1 for write_combine mapping
*
* Use the regular PCI mapping routines to map a PCI resource into userspace.
* FIXME: write combining? maybe automatic for prefetchable regions?
*/
static int
pci_mmap_resource(struct kobject *kobj, struct bin_attribute *attr,
- struct vm_area_struct *vma)
+ struct vm_area_struct *vma, int write_combine)
{
struct pci_dev *pdev = to_pci_dev(container_of(kobj,
struct device, kobj));
@@ -518,7 +519,21 @@
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);
+ return pci_mmap_page_range(pdev, vma, mmap_type, write_combine);
+}
+
+static int
+pci_mmap_resource_uc(struct kobject *kobj, struct bin_attribute *attr,
+ struct vm_area_struct *vma)
+{
+ return pci_mmap_resource(kobj, attr, vma, 0);
+}
+
+static int
+pci_mmap_resource_wc(struct kobject *kobj, struct bin_attribute *attr,
+ struct vm_area_struct *vma)
+{
+ return pci_mmap_resource(kobj, attr, vma, 1);
}
/**
@@ -541,9 +556,46 @@
sysfs_remove_bin_file(&pdev->dev.kobj, res_attr);
kfree(res_attr);
}
+
+ res_attr = pdev->res_attr_wc[i];
+ if (res_attr) {
+ sysfs_remove_bin_file(&pdev->dev.kobj, res_attr);
+ kfree(res_attr);
+ }
}
}
+static int pci_create_attr(struct pci_dev *pdev, int num, int write_combine)
+{
+ /* allocate attribute structure, piggyback attribute name */
+ int name_len = write_combine ? 13 : 10;
+ struct bin_attribute *res_attr;
+ int retval;
+
+ res_attr = kzalloc(sizeof(*res_attr) + name_len, GFP_ATOMIC);
+ if (res_attr) {
+ char *res_attr_name = (char *)(res_attr + 1);
+
+ if (write_combine) {
+ pdev->res_attr_wc[num] = res_attr;
+ sprintf(res_attr_name, "resource%d_wc", num);
+ res_attr->mmap = pci_mmap_resource_wc;
+ } else {
+ pdev->res_attr[num] = res_attr;
+ sprintf(res_attr_name, "resource%d", num);
+ res_attr->mmap = pci_mmap_resource_uc;
+ }
+ res_attr->attr.name = res_attr_name;
+ res_attr->attr.mode = S_IRUSR | S_IWUSR;
+ res_attr->size = pci_resource_len(pdev, num);
+ res_attr->private = &pdev->resource[num];
+ retval = sysfs_create_bin_file(&pdev->dev.kobj, res_attr);
+ } else
+ retval = -ENOMEM;
+
+ return retval;
+}
+
/**
* pci_create_resource_files - create resource files in sysfs for @dev
* @dev: dev in question
@@ -557,31 +609,19 @@
/* Expose the PCI resources from this device as files */
for (i = 0; i < PCI_ROM_RESOURCE; i++) {
- struct bin_attribute *res_attr;
/* skip empty resources */
if (!pci_resource_len(pdev, i))
continue;
- /* allocate attribute structure, piggyback attribute name */
- res_attr = kzalloc(sizeof(*res_attr) + 10, GFP_ATOMIC);
- if (res_attr) {
- char *res_attr_name = (char *)(res_attr + 1);
+ retval = pci_create_attr(pdev, i, 0);
+ /* for prefetchable resources, create a WC mappable file */
+ if (!retval && pdev->resource[i].flags & IORESOURCE_PREFETCH)
+ retval = pci_create_attr(pdev, i, 1);
- pdev->res_attr[i] = res_attr;
- sprintf(res_attr_name, "resource%d", i);
- res_attr->attr.name = res_attr_name;
- res_attr->attr.mode = S_IRUSR | S_IWUSR;
- res_attr->size = pci_resource_len(pdev, i);
- res_attr->mmap = pci_mmap_resource;
- res_attr->private = &pdev->resource[i];
- retval = sysfs_create_bin_file(&pdev->dev.kobj, res_attr);
- if (retval) {
- pci_remove_resource_files(pdev);
- return retval;
- }
- } else {
- return -ENOMEM;
+ if (retval) {
+ pci_remove_resource_files(pdev);
+ return retval;
}
}
return 0;