| Message ID | 20230817235810.596458-1-alistair.francis@wdc.com |
|---|---|
| State | New |
| Headers | show |
| Series | [v6,1/3] PCI/DOE: Expose the DOE features via sysfs | expand |
On 8/17/23 16:58, Alistair Francis wrote: > The PCIe 6 specification added support for the Data Object Exchange (DOE). > When DOE is supported the Discovery Data Object Protocol must be > implemented. The protocol allows a requester to obtain information about > the other DOE features supported by the device. > > The kernel is already querying the DOE features supported and cacheing > the values. This patch exposes the values via sysfs. This will allow > userspace to determine which DOE features are supported by the PCIe > device. > > By exposing the information to userspace tools like lspci can relay the > information to users. By listing all of the supported features we can > allow userspace to parse and support the list, which might include > vendor specific features as well as yet to be supported features. > > Signed-off-by: Alistair Francis <alistair.francis@wdc.com> > --- > v6: > - Use "feature" instead of protocol > - Don't use any devm_* functions > - Add two more patches to the series > v5: > - Return the file name as the file contents > - Code cleanups and simplifications > v4: > - Fixup typos in the documentation > - Make it clear that the file names contain the information > - Small code cleanups > - Remove most #ifdefs > - Remove extra NULL assignment > v3: > - Expose each DOE feature as a separate file > v2: > - Add documentation > - Code cleanups > > This patch will create a doe_features directory for all > PCIe devices without the next two patches > > Documentation/ABI/testing/sysfs-bus-pci | 11 +++ > drivers/pci/doe.c | 112 ++++++++++++++++++++++++ > drivers/pci/pci-sysfs.c | 10 +++ > drivers/pci/pci.h | 3 + > include/linux/pci-doe.h | 1 + > 5 files changed, 137 insertions(+) > > diff --git a/Documentation/ABI/testing/sysfs-bus-pci b/Documentation/ABI/testing/sysfs-bus-pci > index ecf47559f495..199ee5d27d9d 100644 > --- a/Documentation/ABI/testing/sysfs-bus-pci > +++ b/Documentation/ABI/testing/sysfs-bus-pci > @@ -500,3 +500,14 @@ Description: > console drivers from the device. Raw users of pci-sysfs > resourceN attributes must be terminated prior to resizing. > Success of the resizing operation is not guaranteed. > + > +What: /sys/bus/pci/devices/.../doe_features > +Date: August 2023 > +Contact: Linux PCI developers <linux-pci@vger.kernel.org> > +Description: > + This directory contains a list of the supported > + Data Object Exchange (DOE) features. The feature values are in the overly long line above ... > + file name. The contents of each file are the same as the name. > + The value comes from the device and specifies the vendor and > + data object type supported. The lower byte is the data object > + type and the next two bytes are the vendor ID. > diff --git a/drivers/pci/doe.c b/drivers/pci/doe.c > index 1b97a5ab71a9..316aac60ccd5 100644 > --- a/drivers/pci/doe.c > +++ b/drivers/pci/doe.c > @@ -56,6 +56,8 @@ struct pci_doe_mb { > wait_queue_head_t wq; > struct workqueue_struct *work_queue; > unsigned long flags; > + > + struct device_attribute *sysfs_attrs; above naked declaration without CONFIG_SYSFS seems really odd especially following code is under CONFIG_SYSFS, unless it is accessed outside of CONFIG_SYSFS (which I don't think it is a right interface) then ignore this comment .. > }; > > struct pci_doe_protocol { > @@ -92,6 +94,116 @@ struct pci_doe_task { > struct pci_doe_mb *doe_mb; > }; > > +#ifdef CONFIG_SYSFS > +static umode_t pci_doe_sysfs_attr_is_visible(struct kobject *kobj, > + struct attribute *a, int n) > +{ > + struct pci_dev *pdev = to_pci_dev(kobj_to_dev(kobj)); > + unsigned long total_features = 0; > + struct pci_doe_mb *doe_mb; > + unsigned long index, j; > + void *entry; > + > + xa_for_each(&pdev->doe_mbs, index, doe_mb) { > + xa_for_each(&doe_mb->prots, j, entry) > + total_features++; > + } > + > + if (total_features == 0) > + return 0; > + > + return a->mode; > +} > + this removes the need for extra variable to avoids unnecessary loop iterations unless there is bug in this suggestion, why not following ? static umode_t pci_doe_sysfs_attr_is_visible(struct kobject *kobj, struct attribute *a, int n) { struct pci_dev *pdev = to_pci_dev(kobj_to_dev(kobj)); struct pci_doe_mb *doe_mb; unsigned long index, j; void *entry; xa_for_each(&pdev->doe_mbs, index, doe_mb) { xa_for_each(&doe_mb->prots, j, entry) return a->mode; } return 0; } > +static struct attribute *pci_dev_doe_feature_attrs[] = { > + NULL, > +}; > + > +const struct attribute_group pci_dev_doe_feature_group = { > + .name = "doe_features", > + .attrs = pci_dev_doe_feature_attrs, > + .is_visible = pci_doe_sysfs_attr_is_visible, > +}; > + > +static ssize_t pci_doe_sysfs_feature_show(struct device *dev, > + struct device_attribute *attr, > + char *buf) > +{ > + return sysfs_emit(buf, "%s\n", attr->attr.name); > +} > + > +static int pci_doe_sysfs_feature_supports(struct pci_dev *pdev, > + struct pci_doe_mb *doe_mb) > +{ > + struct device *dev = &pdev->dev; > + struct device_attribute *attrs; > + unsigned long num_features = 0; > + unsigned long vid, type; > + unsigned long i; > + void *entry; > + int ret; > + > + xa_for_each(&doe_mb->prots, i, entry) > + num_features++; > + > + attrs = kcalloc(num_features, sizeof(*attrs), GFP_KERNEL); > + if (!attrs) > + return -ENOMEM; > + > + doe_mb->sysfs_attrs = attrs; > + xa_for_each(&doe_mb->prots, i, entry) { > + sysfs_attr_init(&attrs[i].attr); > + vid = xa_to_value(entry) >> 8; > + type = xa_to_value(entry) & 0xFF; > + attrs[i].attr.name = kasprintf(GFP_KERNEL, > + "0x%04lX:%02lX", vid, type); > + if (!attrs[i].attr.name) { > + ret = -ENOMEM; > + goto fail; > + } > + > + attrs[i].attr.mode = 0444; > + attrs[i].show = pci_doe_sysfs_feature_show; > + > + ret = sysfs_add_file_to_group(&dev->kobj, &attrs[i].attr, > + pci_dev_doe_feature_group.name); > + if (ret) > + goto fail; > + } > + > + return 0; > + > +fail: > + doe_mb->sysfs_attrs = NULL; > + xa_for_each(&doe_mb->prots, i, entry) { > + if (attrs[i].show) > + sysfs_remove_file_from_group(&dev->kobj, &attrs[i].attr, > + pci_dev_doe_feature_group.name); > + kfree(attrs[i].attr.name); > + } > + > + kfree(attrs); > + > + return ret; > +} > + > +int doe_sysfs_init(struct pci_dev *pdev) > +{ > + struct pci_doe_mb *doe_mb; > + unsigned long index; > + int ret; > + > + xa_for_each(&pdev->doe_mbs, index, doe_mb) { > + ret = pci_doe_sysfs_feature_supports(pdev, doe_mb); > + > + if (ret) > + return ret; > + } > + > + return 0; > +} > +#endif > + > static int pci_doe_wait(struct pci_doe_mb *doe_mb, unsigned long timeout) > { > if (wait_event_timeout(doe_mb->wq, > diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c > index ab32a91f287b..3f5104cf78b6 100644 > --- a/drivers/pci/pci-sysfs.c > +++ b/drivers/pci/pci-sysfs.c > @@ -16,6 +16,7 @@ > #include <linux/kernel.h> > #include <linux/sched.h> > #include <linux/pci.h> > +#include <linux/pci-doe.h> > #include <linux/stat.h> > #include <linux/export.h> > #include <linux/topology.h> > @@ -1226,6 +1227,12 @@ static int pci_create_resource_files(struct pci_dev *pdev) > int i; > int retval; > > + if (IS_ENABLED(CONFIG_PCI_DOE)) { > + retval = doe_sysfs_init(pdev); > + if (retval) > + return retval; > + } > + > /* Expose the PCI resources from this device as files */ > for (i = 0; i < PCI_STD_NUM_BARS; i++) { > > @@ -1651,6 +1658,9 @@ static const struct attribute_group *pci_dev_attr_groups[] = { > #endif > #ifdef CONFIG_PCIEASPM > &aspm_ctrl_attr_group, > +#endif > +#ifdef CONFIG_PCI_DOE > + &pci_dev_doe_feature_group, > #endif > NULL, > }; > diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h > index a4c397434057..139d37a0d4cd 100644 > --- a/drivers/pci/pci.h > +++ b/drivers/pci/pci.h > @@ -180,6 +180,9 @@ extern const struct attribute_group *pci_dev_groups[]; > extern const struct attribute_group *pcibus_groups[]; > extern const struct device_type pci_dev_type; > extern const struct attribute_group *pci_bus_groups[]; > +#ifdef CONFIG_SYSFS > +extern const struct attribute_group pci_dev_doe_feature_group; > +#endif > > extern unsigned long pci_hotplug_io_size; > extern unsigned long pci_hotplug_mmio_size; > diff --git a/include/linux/pci-doe.h b/include/linux/pci-doe.h > index 1f14aed4354b..4cc13d9ccb50 100644 > --- a/include/linux/pci-doe.h > +++ b/include/linux/pci-doe.h > @@ -22,4 +22,5 @@ int pci_doe(struct pci_doe_mb *doe_mb, u16 vendor, u8 type, > const void *request, size_t request_sz, > void *response, size_t response_sz); > > +int doe_sysfs_init(struct pci_dev *pci_dev); > #endif
Hi Alistair,
kernel test robot noticed the following build warnings:
[auto build test WARNING on pci/next]
[also build test WARNING on pci/for-linus driver-core/driver-core-testing driver-core/driver-core-next driver-core/driver-core-linus linus/master v6.5-rc6 next-20230817]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Alistair-Francis/sysfs-Add-a-attr_is_visible-function-to-attribute_group/20230818-080110
base: https://git.kernel.org/pub/scm/linux/kernel/git/pci/pci.git next
patch link: https://lore.kernel.org/r/20230817235810.596458-1-alistair.francis%40wdc.com
patch subject: [PATCH v6 1/3] PCI/DOE: Expose the DOE features via sysfs
config: loongarch-allyesconfig (https://download.01.org/0day-ci/archive/20230818/202308181341.DWHmL2Au-lkp@intel.com/config)
compiler: loongarch64-linux-gcc (GCC) 12.3.0
reproduce: (https://download.01.org/0day-ci/archive/20230818/202308181341.DWHmL2Au-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202308181341.DWHmL2Au-lkp@intel.com/
All warnings (new ones prefixed by >>):
>> drivers/pci/doe.c:61: warning: Function parameter or member 'sysfs_attrs' not described in 'pci_doe_mb'
vim +61 drivers/pci/doe.c
a4ff8e7a716013 Li Ming 2022-11-16 36
9d24322e887b6a Jonathan Cameron 2022-07-19 37 /**
9d24322e887b6a Jonathan Cameron 2022-07-19 38 * struct pci_doe_mb - State for a single DOE mailbox
9d24322e887b6a Jonathan Cameron 2022-07-19 39 *
9d24322e887b6a Jonathan Cameron 2022-07-19 40 * This state is used to manage a single DOE mailbox capability. All fields
9d24322e887b6a Jonathan Cameron 2022-07-19 41 * should be considered opaque to the consumers and the structure passed into
022b66f38195f6 Lukas Wunner 2023-03-11 42 * the helpers below after being created by pci_doe_create_mb().
9d24322e887b6a Jonathan Cameron 2022-07-19 43 *
9d24322e887b6a Jonathan Cameron 2022-07-19 44 * @pdev: PCI device this mailbox belongs to
9d24322e887b6a Jonathan Cameron 2022-07-19 45 * @cap_offset: Capability offset
9d24322e887b6a Jonathan Cameron 2022-07-19 46 * @prots: Array of protocols supported (encoded as long values)
9d24322e887b6a Jonathan Cameron 2022-07-19 47 * @wq: Wait queue for work item
9d24322e887b6a Jonathan Cameron 2022-07-19 48 * @work_queue: Queue of pci_doe_work items
9d24322e887b6a Jonathan Cameron 2022-07-19 49 * @flags: Bit array of PCI_DOE_FLAG_* flags
9d24322e887b6a Jonathan Cameron 2022-07-19 50 */
9d24322e887b6a Jonathan Cameron 2022-07-19 51 struct pci_doe_mb {
9d24322e887b6a Jonathan Cameron 2022-07-19 52 struct pci_dev *pdev;
9d24322e887b6a Jonathan Cameron 2022-07-19 53 u16 cap_offset;
9d24322e887b6a Jonathan Cameron 2022-07-19 54 struct xarray prots;
9d24322e887b6a Jonathan Cameron 2022-07-19 55
9d24322e887b6a Jonathan Cameron 2022-07-19 56 wait_queue_head_t wq;
9d24322e887b6a Jonathan Cameron 2022-07-19 57 struct workqueue_struct *work_queue;
9d24322e887b6a Jonathan Cameron 2022-07-19 58 unsigned long flags;
2a8556606e90c6 Alistair Francis 2023-08-17 59
2a8556606e90c6 Alistair Francis 2023-08-17 60 struct device_attribute *sysfs_attrs;
9d24322e887b6a Jonathan Cameron 2022-07-19 @61 };
9d24322e887b6a Jonathan Cameron 2022-07-19 62
Hi Alistair,
kernel test robot noticed the following build warnings:
[auto build test WARNING on pci/next]
[also build test WARNING on pci/for-linus driver-core/driver-core-testing driver-core/driver-core-next driver-core/driver-core-linus linus/master v6.5-rc7 next-20230821]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Alistair-Francis/sysfs-Add-a-attr_is_visible-function-to-attribute_group/20230818-080110
base: https://git.kernel.org/pub/scm/linux/kernel/git/pci/pci.git next
patch link: https://lore.kernel.org/r/20230817235810.596458-1-alistair.francis%40wdc.com
patch subject: [PATCH v6 1/3] PCI/DOE: Expose the DOE features via sysfs
config: i386-randconfig-006-20230821 (https://download.01.org/0day-ci/archive/20230822/202308220442.udC7U63t-lkp@intel.com/config)
compiler: clang version 16.0.4 (https://github.com/llvm/llvm-project.git ae42196bc493ffe877a7e3dff8be32035dea4d07)
reproduce: (https://download.01.org/0day-ci/archive/20230822/202308220442.udC7U63t-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202308220442.udC7U63t-lkp@intel.com/
All warnings (new ones prefixed by >>):
>> drivers/pci/doe.c:61: warning: Function parameter or member 'sysfs_attrs' not described in 'pci_doe_mb'
vim +61 drivers/pci/doe.c
a4ff8e7a716013 Li Ming 2022-11-16 36
9d24322e887b6a Jonathan Cameron 2022-07-19 37 /**
9d24322e887b6a Jonathan Cameron 2022-07-19 38 * struct pci_doe_mb - State for a single DOE mailbox
9d24322e887b6a Jonathan Cameron 2022-07-19 39 *
9d24322e887b6a Jonathan Cameron 2022-07-19 40 * This state is used to manage a single DOE mailbox capability. All fields
9d24322e887b6a Jonathan Cameron 2022-07-19 41 * should be considered opaque to the consumers and the structure passed into
022b66f38195f6 Lukas Wunner 2023-03-11 42 * the helpers below after being created by pci_doe_create_mb().
9d24322e887b6a Jonathan Cameron 2022-07-19 43 *
9d24322e887b6a Jonathan Cameron 2022-07-19 44 * @pdev: PCI device this mailbox belongs to
9d24322e887b6a Jonathan Cameron 2022-07-19 45 * @cap_offset: Capability offset
9d24322e887b6a Jonathan Cameron 2022-07-19 46 * @prots: Array of protocols supported (encoded as long values)
9d24322e887b6a Jonathan Cameron 2022-07-19 47 * @wq: Wait queue for work item
9d24322e887b6a Jonathan Cameron 2022-07-19 48 * @work_queue: Queue of pci_doe_work items
9d24322e887b6a Jonathan Cameron 2022-07-19 49 * @flags: Bit array of PCI_DOE_FLAG_* flags
9d24322e887b6a Jonathan Cameron 2022-07-19 50 */
9d24322e887b6a Jonathan Cameron 2022-07-19 51 struct pci_doe_mb {
9d24322e887b6a Jonathan Cameron 2022-07-19 52 struct pci_dev *pdev;
9d24322e887b6a Jonathan Cameron 2022-07-19 53 u16 cap_offset;
9d24322e887b6a Jonathan Cameron 2022-07-19 54 struct xarray prots;
9d24322e887b6a Jonathan Cameron 2022-07-19 55
9d24322e887b6a Jonathan Cameron 2022-07-19 56 wait_queue_head_t wq;
9d24322e887b6a Jonathan Cameron 2022-07-19 57 struct workqueue_struct *work_queue;
9d24322e887b6a Jonathan Cameron 2022-07-19 58 unsigned long flags;
2a8556606e90c6 Alistair Francis 2023-08-17 59
2a8556606e90c6 Alistair Francis 2023-08-17 60 struct device_attribute *sysfs_attrs;
9d24322e887b6a Jonathan Cameron 2022-07-19 @61 };
9d24322e887b6a Jonathan Cameron 2022-07-19 62
diff --git a/Documentation/ABI/testing/sysfs-bus-pci b/Documentation/ABI/testing/sysfs-bus-pci index ecf47559f495..199ee5d27d9d 100644 --- a/Documentation/ABI/testing/sysfs-bus-pci +++ b/Documentation/ABI/testing/sysfs-bus-pci @@ -500,3 +500,14 @@ Description: console drivers from the device. Raw users of pci-sysfs resourceN attributes must be terminated prior to resizing. Success of the resizing operation is not guaranteed. + +What: /sys/bus/pci/devices/.../doe_features +Date: August 2023 +Contact: Linux PCI developers <linux-pci@vger.kernel.org> +Description: + This directory contains a list of the supported + Data Object Exchange (DOE) features. The feature values are in the + file name. The contents of each file are the same as the name. + The value comes from the device and specifies the vendor and + data object type supported. The lower byte is the data object + type and the next two bytes are the vendor ID. diff --git a/drivers/pci/doe.c b/drivers/pci/doe.c index 1b97a5ab71a9..316aac60ccd5 100644 --- a/drivers/pci/doe.c +++ b/drivers/pci/doe.c @@ -56,6 +56,8 @@ struct pci_doe_mb { wait_queue_head_t wq; struct workqueue_struct *work_queue; unsigned long flags; + + struct device_attribute *sysfs_attrs; }; struct pci_doe_protocol { @@ -92,6 +94,116 @@ struct pci_doe_task { struct pci_doe_mb *doe_mb; }; +#ifdef CONFIG_SYSFS +static umode_t pci_doe_sysfs_attr_is_visible(struct kobject *kobj, + struct attribute *a, int n) +{ + struct pci_dev *pdev = to_pci_dev(kobj_to_dev(kobj)); + unsigned long total_features = 0; + struct pci_doe_mb *doe_mb; + unsigned long index, j; + void *entry; + + xa_for_each(&pdev->doe_mbs, index, doe_mb) { + xa_for_each(&doe_mb->prots, j, entry) + total_features++; + } + + if (total_features == 0) + return 0; + + return a->mode; +} + +static struct attribute *pci_dev_doe_feature_attrs[] = { + NULL, +}; + +const struct attribute_group pci_dev_doe_feature_group = { + .name = "doe_features", + .attrs = pci_dev_doe_feature_attrs, + .is_visible = pci_doe_sysfs_attr_is_visible, +}; + +static ssize_t pci_doe_sysfs_feature_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + return sysfs_emit(buf, "%s\n", attr->attr.name); +} + +static int pci_doe_sysfs_feature_supports(struct pci_dev *pdev, + struct pci_doe_mb *doe_mb) +{ + struct device *dev = &pdev->dev; + struct device_attribute *attrs; + unsigned long num_features = 0; + unsigned long vid, type; + unsigned long i; + void *entry; + int ret; + + xa_for_each(&doe_mb->prots, i, entry) + num_features++; + + attrs = kcalloc(num_features, sizeof(*attrs), GFP_KERNEL); + if (!attrs) + return -ENOMEM; + + doe_mb->sysfs_attrs = attrs; + xa_for_each(&doe_mb->prots, i, entry) { + sysfs_attr_init(&attrs[i].attr); + vid = xa_to_value(entry) >> 8; + type = xa_to_value(entry) & 0xFF; + attrs[i].attr.name = kasprintf(GFP_KERNEL, + "0x%04lX:%02lX", vid, type); + if (!attrs[i].attr.name) { + ret = -ENOMEM; + goto fail; + } + + attrs[i].attr.mode = 0444; + attrs[i].show = pci_doe_sysfs_feature_show; + + ret = sysfs_add_file_to_group(&dev->kobj, &attrs[i].attr, + pci_dev_doe_feature_group.name); + if (ret) + goto fail; + } + + return 0; + +fail: + doe_mb->sysfs_attrs = NULL; + xa_for_each(&doe_mb->prots, i, entry) { + if (attrs[i].show) + sysfs_remove_file_from_group(&dev->kobj, &attrs[i].attr, + pci_dev_doe_feature_group.name); + kfree(attrs[i].attr.name); + } + + kfree(attrs); + + return ret; +} + +int doe_sysfs_init(struct pci_dev *pdev) +{ + struct pci_doe_mb *doe_mb; + unsigned long index; + int ret; + + xa_for_each(&pdev->doe_mbs, index, doe_mb) { + ret = pci_doe_sysfs_feature_supports(pdev, doe_mb); + + if (ret) + return ret; + } + + return 0; +} +#endif + static int pci_doe_wait(struct pci_doe_mb *doe_mb, unsigned long timeout) { if (wait_event_timeout(doe_mb->wq, diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c index ab32a91f287b..3f5104cf78b6 100644 --- a/drivers/pci/pci-sysfs.c +++ b/drivers/pci/pci-sysfs.c @@ -16,6 +16,7 @@ #include <linux/kernel.h> #include <linux/sched.h> #include <linux/pci.h> +#include <linux/pci-doe.h> #include <linux/stat.h> #include <linux/export.h> #include <linux/topology.h> @@ -1226,6 +1227,12 @@ static int pci_create_resource_files(struct pci_dev *pdev) int i; int retval; + if (IS_ENABLED(CONFIG_PCI_DOE)) { + retval = doe_sysfs_init(pdev); + if (retval) + return retval; + } + /* Expose the PCI resources from this device as files */ for (i = 0; i < PCI_STD_NUM_BARS; i++) { @@ -1651,6 +1658,9 @@ static const struct attribute_group *pci_dev_attr_groups[] = { #endif #ifdef CONFIG_PCIEASPM &aspm_ctrl_attr_group, +#endif +#ifdef CONFIG_PCI_DOE + &pci_dev_doe_feature_group, #endif NULL, }; diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h index a4c397434057..139d37a0d4cd 100644 --- a/drivers/pci/pci.h +++ b/drivers/pci/pci.h @@ -180,6 +180,9 @@ extern const struct attribute_group *pci_dev_groups[]; extern const struct attribute_group *pcibus_groups[]; extern const struct device_type pci_dev_type; extern const struct attribute_group *pci_bus_groups[]; +#ifdef CONFIG_SYSFS +extern const struct attribute_group pci_dev_doe_feature_group; +#endif extern unsigned long pci_hotplug_io_size; extern unsigned long pci_hotplug_mmio_size; diff --git a/include/linux/pci-doe.h b/include/linux/pci-doe.h index 1f14aed4354b..4cc13d9ccb50 100644 --- a/include/linux/pci-doe.h +++ b/include/linux/pci-doe.h @@ -22,4 +22,5 @@ int pci_doe(struct pci_doe_mb *doe_mb, u16 vendor, u8 type, const void *request, size_t request_sz, void *response, size_t response_sz); +int doe_sysfs_init(struct pci_dev *pci_dev); #endif
The PCIe 6 specification added support for the Data Object Exchange (DOE). When DOE is supported the Discovery Data Object Protocol must be implemented. The protocol allows a requester to obtain information about the other DOE features supported by the device. The kernel is already querying the DOE features supported and cacheing the values. This patch exposes the values via sysfs. This will allow userspace to determine which DOE features are supported by the PCIe device. By exposing the information to userspace tools like lspci can relay the information to users. By listing all of the supported features we can allow userspace to parse and support the list, which might include vendor specific features as well as yet to be supported features. Signed-off-by: Alistair Francis <alistair.francis@wdc.com> --- v6: - Use "feature" instead of protocol - Don't use any devm_* functions - Add two more patches to the series v5: - Return the file name as the file contents - Code cleanups and simplifications v4: - Fixup typos in the documentation - Make it clear that the file names contain the information - Small code cleanups - Remove most #ifdefs - Remove extra NULL assignment v3: - Expose each DOE feature as a separate file v2: - Add documentation - Code cleanups This patch will create a doe_features directory for all PCIe devices without the next two patches Documentation/ABI/testing/sysfs-bus-pci | 11 +++ drivers/pci/doe.c | 112 ++++++++++++++++++++++++ drivers/pci/pci-sysfs.c | 10 +++ drivers/pci/pci.h | 3 + include/linux/pci-doe.h | 1 + 5 files changed, 137 insertions(+)