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Commit 45aec1ae authored by venkatesh.pallipadi@intel.com's avatar venkatesh.pallipadi@intel.com Committed by Ingo Molnar
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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: default avatarVenkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: default avatarSuresh Siddha <suresh.b.siddha@intel.com>
Acked-by: default avatarJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
parent b7f09ae5

Documentation/filesystems/sysfs-pci.txt

+1 −0
Original line number Diff line number Diff line
@@ -36,6 +36,7 @@ files, each with their own function. 
       local_cpus	   nearby CPU mask (cpumask, ro)

       resource		   PCI resource host addresses (ascii, ro)

       resource0..N	   PCI resource N, if present (binary, mmap)

       resource0_wc..N_wc  PCI WC map resource N, if prefetchable (binary, mmap)

       rom		   PCI ROM resource, if present (binary, ro)

       subsystem_device	   PCI subsystem device (ascii, ro)

       subsystem_vendor	   PCI subsystem vendor (ascii, ro)

drivers/pci/pci-sysfs.c

+62 −22
Original line number Diff line number Diff line
@@ -489,13 +489,14 @@ pci_mmap_legacy_mem(struct kobject *kobj, struct bin_attribute *attr, 
 * @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 @@ 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;



	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 @@ pci_remove_resource_files(struct pci_dev *pdev) 
			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
@@ -557,32 +609,20 @@ static int pci_create_resource_files(struct pci_dev *pdev) 


	/* 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;

		}

	}

	return 0;

}

include/linux/pci.h

+1 −0
Original line number Diff line number Diff line
@@ -206,6 +206,7 @@ struct pci_dev { 
	struct bin_attribute *rom_attr; /* attribute descriptor for sysfs ROM entry */

	int rom_attr_enabled;		/* has display of the rom attribute been enabled? */

	struct bin_attribute *res_attr[DEVICE_COUNT_RESOURCE]; /* sysfs file for resources */

	struct bin_attribute *res_attr_wc[DEVICE_COUNT_RESOURCE]; /* sysfs file for WC mapping of resources */

#ifdef CONFIG_PCI_MSI

	struct list_head msi_list;

#endif