On 21/07/11 04:51PM, Raphael Norwitz wrote: > On Mon, Jul 05, 2021 at 07:51:34PM +0530, Amey Narkhede wrote: > > Add reset_method sysfs attribute to enable user to query and set user > > preferred device reset methods and their ordering. > > > > Co-developed-by: Alex Williamson <alex.williamson@xxxxxxxxxx> > > Signed-off-by: Alex Williamson <alex.williamson@xxxxxxxxxx> > > Signed-off-by: Amey Narkhede <ameynarkhede03@xxxxxxxxx> > > Just some spacing NITs. > > Reviewed-by: Raphael Norwitz <raphael.norwitz@xxxxxxxxxxx> > > > --- > > Documentation/ABI/testing/sysfs-bus-pci | 19 +++++ > > drivers/pci/pci-sysfs.c | 103 ++++++++++++++++++++++++ > > 2 files changed, 122 insertions(+) > > > > diff --git a/Documentation/ABI/testing/sysfs-bus-pci b/Documentation/ABI/testing/sysfs-bus-pci > > index ef00fada2..43f4e33c7 100644 > > --- a/Documentation/ABI/testing/sysfs-bus-pci > > +++ b/Documentation/ABI/testing/sysfs-bus-pci > > @@ -121,6 +121,25 @@ Description: > > child buses, and re-discover devices removed earlier > > from this part of the device tree. > > > > +What: /sys/bus/pci/devices/.../reset_method > > +Date: March 2021 > > +Contact: Amey Narkhede <ameynarkhede03@xxxxxxxxx> > > +Description: > > + Some devices allow an individual function to be reset > > + without affecting other functions in the same slot. > > + > > + For devices that have this support, a file named > > + reset_method will be present in sysfs. Initially reading > > + this file will give names of the device supported reset > > + methods and their ordering. After write, this file will > > + give names and ordering of currently enabled reset methods. > > + Writing the name or comma separated list of names of any of > > + the device supported reset methods to this file will set > > + the reset methods and their ordering to be used when > > + resetting the device. Writing empty string to this file > > + will disable ability to reset the device and writing > > + "default" will return to the original value. > > + > > What: /sys/bus/pci/devices/.../reset > > Date: July 2009 > > Contact: Michael S. Tsirkin <mst@xxxxxxxxxx> > > diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c > > index 316f70c3e..8a740e211 100644 > > --- a/drivers/pci/pci-sysfs.c > > +++ b/drivers/pci/pci-sysfs.c > > @@ -1334,6 +1334,108 @@ static const struct attribute_group pci_dev_rom_attr_group = { > > .is_bin_visible = pci_dev_rom_attr_is_visible, > > }; > > > > +static ssize_t reset_method_show(struct device *dev, > > Nit: spaces on the following two lines. "struct device_attribute *attr" > and "char *buf" should be in line with "struct device *dev" > Not sure what happened when creating the patches but on my editor spaces seems to consistent as you suggested here. For some reason git format-patch is acting weird. Thanks, Amey > > + struct device_attribute *attr, > > + char *buf) > > +{ > > + struct pci_dev *pdev = to_pci_dev(dev); > > + ssize_t len = 0; > > + int i, idx; > > + > > + for (i = 0; i < PCI_NUM_RESET_METHODS; i++) { > > + idx = pdev->reset_methods[i]; > > + if (!idx) > > + break; > > + > > + len += sysfs_emit_at(buf, len, "%s%s", len ? "," : "", > > + pci_reset_fn_methods[idx].name); > > + } > > + > > + if (len) > > + len += sysfs_emit_at(buf, len, "\n"); > > + > > + return len; > > +} > > + > > +static ssize_t reset_method_store(struct device *dev, > > Nit: spaces on the following two lines > > > + struct device_attribute *attr, > > + const char *buf, size_t count) > > +{ > > + struct pci_dev *pdev = to_pci_dev(dev); > > + int n = 0; > > + char *name, *options = NULL; > > + u8 reset_methods[PCI_NUM_RESET_METHODS] = { 0 }; > > + > > + if (count >= (PAGE_SIZE - 1)) > > + return -EINVAL; > > + > > + if (sysfs_streq(buf, "")) { > > + pci_warn(pdev, "All device reset methods disabled by user"); > > + goto set_reset_methods; > > + } > > + > > + if (sysfs_streq(buf, "default")) { > > + pci_init_reset_methods(pdev); > > + return count; > > + } > > + > > + options = kstrndup(buf, count, GFP_KERNEL); > > + if (!options) > > + return -ENOMEM; > > + > > + while ((name = strsep(&options, ",")) != NULL) { > > + int i; > > + > > + if (sysfs_streq(name, "")) > > + continue; > > + > > + name = strim(name); > > + > > + for (i = 1; i < PCI_NUM_RESET_METHODS; i++) { > > + if (sysfs_streq(name, pci_reset_fn_methods[i].name) && > > + !pci_reset_fn_methods[i].reset_fn(pdev, 1)) { > > + reset_methods[n++] = i; > > + break; > > + } > > + } > > + > > + if (i == PCI_NUM_RESET_METHODS) { > > + kfree(options); > > + return -EINVAL; > > + } > > + } > > + > > + if (!pci_reset_fn_methods[1].reset_fn(pdev, 1) && reset_methods[0] != 1) > > + pci_warn(pdev, "Device specific reset disabled/de-prioritized by user"); > > + > > +set_reset_methods: > > + memcpy(pdev->reset_methods, reset_methods, sizeof(reset_methods)); > > + kfree(options); > > + return count; > > +} > > +static DEVICE_ATTR_RW(reset_method); > > + > > +static struct attribute *pci_dev_reset_method_attrs[] = { > > + &dev_attr_reset_method.attr, > > + NULL, > > +}; > > + > > +static umode_t pci_dev_reset_method_attr_is_visible(struct kobject *kobj, > > Nit: ditto - spacing. > > > + struct attribute *a, int n) > > +{ > > + struct pci_dev *pdev = to_pci_dev(kobj_to_dev(kobj)); > > + > > + if (!pci_reset_supported(pdev)) > > + return 0; > > + > > + return a->mode; > > +} > > + > > +static const struct attribute_group pci_dev_reset_method_attr_group = { > > + .attrs = pci_dev_reset_method_attrs, > > + .is_visible = pci_dev_reset_method_attr_is_visible, > > +}; > > + > > static ssize_t reset_store(struct device *dev, struct device_attribute *attr, > > Nit: spacing following line. > > > const char *buf, size_t count) > > { > > @@ -1491,6 +1593,7 @@ const struct attribute_group *pci_dev_groups[] = { > > &pci_dev_config_attr_group, > > &pci_dev_rom_attr_group, > > &pci_dev_reset_attr_group, > > + &pci_dev_reset_method_attr_group, > > &pci_dev_vpd_attr_group, > > #ifdef CONFIG_DMI > > &pci_dev_smbios_attr_group, > > -- > > 2.32.0 > > > >