linux/drivers/pci/hotplug/shpchp_sysfs.c
Krzysztof Wilczyński f8cf6e513e PCI/sysfs: Use sysfs_emit() and sysfs_emit_at() in "show" functions
The sysfs_emit() and sysfs_emit_at() functions were introduced to make
it less ambiguous which function is preferred when writing to the output
buffer in a device attribute's "show" callback [1].

Convert the PCI sysfs object "show" functions from sprintf(), snprintf()
and scnprintf() to sysfs_emit() and sysfs_emit_at() accordingly, as the
latter is aware of the PAGE_SIZE buffer and correctly returns the number
of bytes written into the buffer.

No functional change intended.

[1] Documentation/filesystems/sysfs.rst

Related commit: ad025f8e46 ("PCI/sysfs: Use sysfs_emit() and
sysfs_emit_at() in "show" functions").

Link: https://lore.kernel.org/r/20210603000112.703037-2-kw@linux.com
Signed-off-by: Krzysztof Wilczyński <kw@linux.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
2021-06-03 22:14:47 -05:00

87 lines
2.5 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Compaq Hot Plug Controller Driver
*
* Copyright (c) 1995,2001 Compaq Computer Corporation
* Copyright (c) 2001,2003 Greg Kroah-Hartman (greg@kroah.com)
* Copyright (c) 2001 IBM Corp.
*
* All rights reserved.
*
* Send feedback to <greg@kroah.com>
*
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/pci.h>
#include "shpchp.h"
/* A few routines that create sysfs entries for the hot plug controller */
static ssize_t show_ctrl(struct device *dev, struct device_attribute *attr, char *buf)
{
struct pci_dev *pdev;
int index, busnr;
struct resource *res;
struct pci_bus *bus;
size_t len = 0;
pdev = to_pci_dev(dev);
bus = pdev->subordinate;
len += sysfs_emit_at(buf, len, "Free resources: memory\n");
pci_bus_for_each_resource(bus, res, index) {
if (res && (res->flags & IORESOURCE_MEM) &&
!(res->flags & IORESOURCE_PREFETCH)) {
len += sysfs_emit_at(buf, len,
"start = %8.8llx, length = %8.8llx\n",
(unsigned long long)res->start,
(unsigned long long)resource_size(res));
}
}
len += sysfs_emit_at(buf, len, "Free resources: prefetchable memory\n");
pci_bus_for_each_resource(bus, res, index) {
if (res && (res->flags & IORESOURCE_MEM) &&
(res->flags & IORESOURCE_PREFETCH)) {
len += sysfs_emit_at(buf, len,
"start = %8.8llx, length = %8.8llx\n",
(unsigned long long)res->start,
(unsigned long long)resource_size(res));
}
}
len += sysfs_emit_at(buf, len, "Free resources: IO\n");
pci_bus_for_each_resource(bus, res, index) {
if (res && (res->flags & IORESOURCE_IO)) {
len += sysfs_emit_at(buf, len,
"start = %8.8llx, length = %8.8llx\n",
(unsigned long long)res->start,
(unsigned long long)resource_size(res));
}
}
len += sysfs_emit_at(buf, len, "Free resources: bus numbers\n");
for (busnr = bus->busn_res.start; busnr <= bus->busn_res.end; busnr++) {
if (!pci_find_bus(pci_domain_nr(bus), busnr))
break;
}
if (busnr < bus->busn_res.end)
len += sysfs_emit_at(buf, len,
"start = %8.8x, length = %8.8x\n",
busnr, (int)(bus->busn_res.end - busnr));
return len;
}
static DEVICE_ATTR(ctrl, S_IRUGO, show_ctrl, NULL);
int shpchp_create_ctrl_files(struct controller *ctrl)
{
return device_create_file(&ctrl->pci_dev->dev, &dev_attr_ctrl);
}
void shpchp_remove_ctrl_files(struct controller *ctrl)
{
device_remove_file(&ctrl->pci_dev->dev, &dev_attr_ctrl);
}