Re: [PATCH v3 1/4] PCI: sysfs: Define device attributes with DEVICE_ATTR*

Ruslan Bilovol
2020-03-15T02:34:13Z

On Thu, Aug 15, 2019 at 7:01 PM Kelsey Skunberg
<skunberg.kelsey@gmail.com> wrote:
>
> Defining device attributes should be done through the helper
> DEVICE_ATTR_RO(), DEVICE_ATTR_WO(), or similar. Change all instances using
> __ATTR* to now use its equivalent DEVICE_ATTR*.
>
> Example of old:
>
> static struct device_attribute dev_name_##_attr=__ATTR_RO(_name);
>
> Example of new:
>
> static DEVICE_ATTR_RO(_name);
>
> Signed-off-by: Kelsey Skunberg <skunberg.kelsey@gmail.com>
> ---
> drivers/pci/pci-sysfs.c | 59 +++++++++++++++++++----------------------
> 1 file changed, 27 insertions(+), 32 deletions(-)
>
> diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c
> index 965c72104150..8af7944fdccb 100644
> --- a/drivers/pci/pci-sysfs.c
> +++ b/drivers/pci/pci-sysfs.c
> @@ -464,9 +464,7 @@ static ssize_t dev_rescan_store(struct device *dev,
> }
> return count;
> }
> -static struct device_attribute dev_rescan_attr = __ATTR(rescan,
> - (S_IWUSR|S_IWGRP),
> - NULL, dev_rescan_store);
> +static DEVICE_ATTR(rescan, (S_IWUSR | S_IWGRP), NULL, dev_rescan_store);
>
> static ssize_t remove_store(struct device *dev, struct device_attribute *attr,
> const char *buf, size_t count)
> @@ -480,9 +478,8 @@ static ssize_t remove_store(struct device *dev, struct device_attribute *attr,
> pci_stop_and_remove_bus_device_locked(to_pci_dev(dev));
> return count;
> }
> -static struct device_attribute dev_remove_attr = __ATTR_IGNORE_LOCKDEP(remove,
> - (S_IWUSR|S_IWGRP),
> - NULL, remove_store);
> +static DEVICE_ATTR_IGNORE_LOCKDEP(remove, (S_IWUSR | S_IWGRP), NULL,
> + remove_store);
>
> static ssize_t dev_bus_rescan_store(struct device *dev,
> struct device_attribute *attr,
> @@ -504,7 +501,7 @@ static ssize_t dev_bus_rescan_store(struct device *dev,
> }
> return count;
> }
> -static DEVICE_ATTR(rescan, (S_IWUSR|S_IWGRP), NULL, dev_bus_rescan_store);
> +static DEVICE_ATTR(bus_rescan, (S_IWUSR | S_IWGRP), NULL, dev_bus_rescan_store);

This patch renamed 'rescan' to 'bus_rescan' and broke my userspace application.
There is also mismatch now between real functionality and documentation
Documentation/ABI/testing/sysfs-bus-pci which still contains old "rescan"
descriptions.

Another patch from this patch series also renamed 'rescan' to 'dev_rescan'

Here is a comparison between two stable kernels (with and without this
patch series):

v5.4
# find /sys -name '*rescan'
/sys/devices/pci0000:00/0000:00:01.2/dev_rescan
/sys/devices/pci0000:00/0000:00:01.0/dev_rescan
/sys/devices/pci0000:00/0000:00:04.0/dev_rescan
/sys/devices/pci0000:00/0000:00:00.0/dev_rescan
/sys/devices/pci0000:00/pci_bus/0000:00/bus_rescan
/sys/devices/pci0000:00/0000:00:01.3/dev_rescan
/sys/devices/pci0000:00/0000:00:03.0/dev_rescan
/sys/devices/pci0000:00/0000:00:01.1/dev_rescan
/sys/devices/pci0000:00/0000:00:02.0/dev_rescan
/sys/devices/pci0000:00/0000:00:05.0/dev_rescan
/sys/bus/pci/rescan

v4.19
# find /sys -name '*rescan'
/sys/devices/pci0000:00/0000:00:01.2/rescan
/sys/devices/pci0000:00/0000:00:01.0/rescan
/sys/devices/pci0000:00/0000:00:04.0/rescan
/sys/devices/pci0000:00/0000:00:00.0/rescan
/sys/devices/pci0000:00/pci_bus/0000:00/rescan
/sys/devices/pci0000:00/0000:00:01.3/rescan
/sys/devices/pci0000:00/0000:00:03.0/rescan
/sys/devices/pci0000:00/0000:00:01.1/rescan
/sys/devices/pci0000:00/0000:00:02.0/rescan
/sys/devices/pci0000:00/0000:00:05.0/rescan
/sys/bus/pci/rescan

Do we maintain this kind of API as non-changeable?

Thanks,
Ruslan

>
> #if defined(CONFIG_PM) && defined(CONFIG_ACPI)
> static ssize_t d3cold_allowed_store(struct device *dev,
> @@ -687,16 +684,14 @@ static ssize_t sriov_drivers_autoprobe_store(struct device *dev,
> return count;
> }
>
> -static struct device_attribute sriov_totalvfs_attr = __ATTR_RO(sriov_totalvfs);
> -static struct device_attribute sriov_numvfs_attr =
> - __ATTR(sriov_numvfs, (S_IRUGO|S_IWUSR|S_IWGRP),
> - sriov_numvfs_show, sriov_numvfs_store);
> -static struct device_attribute sriov_offset_attr = __ATTR_RO(sriov_offset);
> -static struct device_attribute sriov_stride_attr = __ATTR_RO(sriov_stride);
> -static struct device_attribute sriov_vf_device_attr = __ATTR_RO(sriov_vf_device);
> -static struct device_attribute sriov_drivers_autoprobe_attr =
> - __ATTR(sriov_drivers_autoprobe, (S_IRUGO|S_IWUSR|S_IWGRP),
> - sriov_drivers_autoprobe_show, sriov_drivers_autoprobe_store);
> +static DEVICE_ATTR_RO(sriov_totalvfs);
> +static DEVICE_ATTR(sriov_numvfs, (S_IRUGO | S_IWUSR | S_IWGRP),
> + sriov_numvfs_show, sriov_numvfs_store);
> +static DEVICE_ATTR_RO(sriov_offset);
> +static DEVICE_ATTR_RO(sriov_stride);
> +static DEVICE_ATTR_RO(sriov_vf_device);
> +static DEVICE_ATTR(sriov_drivers_autoprobe, (S_IRUGO | S_IWUSR | S_IWGRP),
> + sriov_drivers_autoprobe_show, sriov_drivers_autoprobe_store);
> #endif /* CONFIG_PCI_IOV */
>
> static ssize_t driver_override_store(struct device *dev,
> @@ -792,7 +787,7 @@ static struct attribute *pcie_dev_attrs[] = {
> };
>
> static struct attribute *pcibus_attrs[] = {
> - &dev_attr_rescan.attr,
> + &dev_attr_bus_rescan.attr,
> &dev_attr_cpuaffinity.attr,
> &dev_attr_cpulistaffinity.attr,
> NULL,
> @@ -820,7 +815,7 @@ static ssize_t boot_vga_show(struct device *dev, struct device_attribute *attr,
> !!(pdev->resource[PCI_ROM_RESOURCE].flags &
> IORESOURCE_ROM_SHADOW));
> }
> -static struct device_attribute vga_attr = __ATTR_RO(boot_vga);
> +static DEVICE_ATTR_RO(boot_vga);
>
> static ssize_t pci_read_config(struct file *filp, struct kobject *kobj,
> struct bin_attribute *bin_attr, char *buf,
> @@ -1458,7 +1453,7 @@ static ssize_t reset_store(struct device *dev, struct device_attribute *attr,
> return count;
> }
>
> -static struct device_attribute reset_attr = __ATTR(reset, 0200, NULL, reset_store);
> +static DEVICE_ATTR(reset, 0200, NULL, reset_store);
>
> static int pci_create_capabilities_sysfs(struct pci_dev *dev)
> {
> @@ -1468,7 +1463,7 @@ static int pci_create_capabilities_sysfs(struct pci_dev *dev)
> pcie_aspm_create_sysfs_dev_files(dev);
>
> if (dev->reset_fn) {
> - retval = device_create_file(&dev->dev, &reset_attr);
> + retval = device_create_file(&dev->dev, &dev_attr_reset);
> if (retval)
> goto error;
> }
> @@ -1553,7 +1548,7 @@ static void pci_remove_capabilities_sysfs(struct pci_dev *dev)
> pcie_vpd_remove_sysfs_dev_files(dev);
> pcie_aspm_remove_sysfs_dev_files(dev);
> if (dev->reset_fn) {
> - device_remove_file(&dev->dev, &reset_attr);
> + device_remove_file(&dev->dev, &dev_attr_reset);
> dev->reset_fn = 0;
> }
> }
> @@ -1606,7 +1601,7 @@ static int __init pci_sysfs_init(void)
> late_initcall(pci_sysfs_init);
>
> static struct attribute *pci_dev_dev_attrs[] = {
> - &vga_attr.attr,
> + &dev_attr_boot_vga.attr,
> NULL,
> };
>
> @@ -1616,7 +1611,7 @@ static umode_t pci_dev_attrs_are_visible(struct kobject *kobj,
> struct device *dev = kobj_to_dev(kobj);
> struct pci_dev *pdev = to_pci_dev(dev);
>
> - if (a == &vga_attr.attr)
> + if (a == &dev_attr_boot_vga.attr)
> if ((pdev->class >> 8) != PCI_CLASS_DISPLAY_VGA)
> return 0;
>
> @@ -1624,8 +1619,8 @@ static umode_t pci_dev_attrs_are_visible(struct kobject *kobj,
> }
>
> static struct attribute *pci_dev_hp_attrs[] = {
> - &dev_remove_attr.attr,
> - &dev_rescan_attr.attr,
> + &dev_attr_remove.attr,
> + &dev_attr_rescan.attr,
> NULL,
> };
>
> @@ -1699,12 +1694,12 @@ static const struct attribute_group pci_dev_hp_attr_group = {
>
> #ifdef CONFIG_PCI_IOV
> static struct attribute *sriov_dev_attrs[] = {
> - &sriov_totalvfs_attr.attr,
> - &sriov_numvfs_attr.attr,
> - &sriov_offset_attr.attr,
> - &sriov_stride_attr.attr,
> - &sriov_vf_device_attr.attr,
> - &sriov_drivers_autoprobe_attr.attr,
> + &dev_attr_sriov_totalvfs.attr,
> + &dev_attr_sriov_numvfs.attr,
> + &dev_attr_sriov_offset.attr,
> + &dev_attr_sriov_stride.attr,
> + &dev_attr_sriov_vf_device.attr,
> + &dev_attr_sriov_drivers_autoprobe.attr,
> NULL,
> };
>
> --
> 2.20.1
>