2018-01-22 08:18:13 -07:00
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// SPDX-License-Identifier: GPL-2.0
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2005-04-16 15:20:36 -07:00
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/*
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* fs/sysfs/group.c - Operations for adding/removing multiple files at once.
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*
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* Copyright (c) 2003 Patrick Mochel
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* Copyright (c) 2003 Open Source Development Lab
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2013-08-21 16:14:11 -07:00
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* Copyright (c) 2013 Greg Kroah-Hartman
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* Copyright (c) 2013 The Linux Foundation
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2005-04-16 15:20:36 -07:00
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*/
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#include <linux/kobject.h>
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#include <linux/module.h>
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#include <linux/dcache.h>
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2005-06-23 00:09:12 -07:00
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#include <linux/namei.h>
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2005-04-16 15:20:36 -07:00
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#include <linux/err.h>
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2020-02-26 20:37:13 -07:00
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#include <linux/fs.h>
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2005-04-16 15:20:36 -07:00
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#include "sysfs.h"
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2014-05-05 06:17:20 -07:00
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static void remove_files(struct kernfs_node *parent,
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2007-06-13 12:27:22 -07:00
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const struct attribute_group *grp)
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2005-04-16 15:20:36 -07:00
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{
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2013-08-21 16:07:29 -07:00
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struct attribute *const *attr;
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struct bin_attribute *const *bin_attr;
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2005-04-16 15:20:36 -07:00
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2013-07-14 16:05:55 -07:00
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if (grp->attrs)
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for (attr = grp->attrs; *attr; attr++)
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2013-12-11 12:11:53 -07:00
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kernfs_remove_by_name(parent, (*attr)->name);
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2013-07-14 16:05:55 -07:00
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if (grp->bin_attrs)
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for (bin_attr = grp->bin_attrs; *bin_attr; bin_attr++)
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2014-05-05 06:17:20 -07:00
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kernfs_remove_by_name(parent, (*bin_attr)->attr.name);
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2005-04-16 15:20:36 -07:00
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}
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sysfs: Introduce a mechanism to hide static attribute_groups
Add a mechanism for named attribute_groups to hide their directory at
sysfs_update_group() time, or otherwise skip emitting the group
directory when the group is first registered. It piggybacks on
is_visible() in a similar manner as SYSFS_PREALLOC, i.e. special flags
in the upper bits of the returned mode. To use it, specify a symbol
prefix to DEFINE_SYSFS_GROUP_VISIBLE(), and then pass that same prefix
to SYSFS_GROUP_VISIBLE() when assigning the @is_visible() callback:
DEFINE_SYSFS_GROUP_VISIBLE($prefix)
struct attribute_group $prefix_group = {
.name = $name,
.is_visible = SYSFS_GROUP_VISIBLE($prefix),
};
SYSFS_GROUP_VISIBLE() expects a definition of $prefix_group_visible()
and $prefix_attr_visible(), where $prefix_group_visible() just returns
true / false and $prefix_attr_visible() behaves as normal.
The motivation for this capability is to centralize PCI device
authentication in the PCI core with a named sysfs group while keeping
that group hidden for devices and platforms that do not meet the
requirements. In a PCI topology, most devices will not support
authentication, a small subset will support just PCI CMA (Component
Measurement and Authentication), a smaller subset will support PCI CMA +
PCIe IDE (Link Integrity and Encryption), and only next generation
server hosts will start to include a platform TSM (TEE Security
Manager).
Without this capability the alternatives are:
* Check if all attributes are invisible and if so, hide the directory.
Beyond trouble getting this to work [1], this is an ABI change for
scenarios if userspace happens to depend on group visibility absent any
attributes. I.e. this new capability avoids regression since it does
not retroactively apply to existing cases.
* Publish an empty /sys/bus/pci/devices/$pdev/tsm/ directory for all PCI
devices (i.e. for the case when TSM platform support is present, but
device support is absent). Unfortunate that this will be a vestigial
empty directory in the vast majority of cases.
* Reintroduce usage of runtime calls to sysfs_{create,remove}_group()
in the PCI core. Bjorn has already indicated that he does not want to
see any growth of pci_sysfs_init() [2].
* Drop the named group and simulate a directory by prefixing all
TSM-related attributes with "tsm_". Unfortunate to not use the naming
capability of a sysfs group as intended.
In comparison, there is a small potential for regression if for some
reason an @is_visible() callback had dependencies on how many times it
was called. Additionally, it is no longer an error to update a group
that does not have its directory already present, and it is no longer a
WARN() to remove a group that was never visible.
Link: https://lore.kernel.org/all/2024012321-envious-procedure-4a58@gregkh/ [1]
Link: https://lore.kernel.org/linux-pci/20231019200110.GA1410324@bhelgaas/ [2]
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/2024013028-deflator-flaring-ec62@gregkh
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-01-30 11:46:27 -07:00
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static umode_t __first_visible(const struct attribute_group *grp, struct kobject *kobj)
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{
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2024-02-22 13:40:54 -07:00
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if (grp->attrs && grp->attrs[0] && grp->is_visible)
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sysfs: Introduce a mechanism to hide static attribute_groups
Add a mechanism for named attribute_groups to hide their directory at
sysfs_update_group() time, or otherwise skip emitting the group
directory when the group is first registered. It piggybacks on
is_visible() in a similar manner as SYSFS_PREALLOC, i.e. special flags
in the upper bits of the returned mode. To use it, specify a symbol
prefix to DEFINE_SYSFS_GROUP_VISIBLE(), and then pass that same prefix
to SYSFS_GROUP_VISIBLE() when assigning the @is_visible() callback:
DEFINE_SYSFS_GROUP_VISIBLE($prefix)
struct attribute_group $prefix_group = {
.name = $name,
.is_visible = SYSFS_GROUP_VISIBLE($prefix),
};
SYSFS_GROUP_VISIBLE() expects a definition of $prefix_group_visible()
and $prefix_attr_visible(), where $prefix_group_visible() just returns
true / false and $prefix_attr_visible() behaves as normal.
The motivation for this capability is to centralize PCI device
authentication in the PCI core with a named sysfs group while keeping
that group hidden for devices and platforms that do not meet the
requirements. In a PCI topology, most devices will not support
authentication, a small subset will support just PCI CMA (Component
Measurement and Authentication), a smaller subset will support PCI CMA +
PCIe IDE (Link Integrity and Encryption), and only next generation
server hosts will start to include a platform TSM (TEE Security
Manager).
Without this capability the alternatives are:
* Check if all attributes are invisible and if so, hide the directory.
Beyond trouble getting this to work [1], this is an ABI change for
scenarios if userspace happens to depend on group visibility absent any
attributes. I.e. this new capability avoids regression since it does
not retroactively apply to existing cases.
* Publish an empty /sys/bus/pci/devices/$pdev/tsm/ directory for all PCI
devices (i.e. for the case when TSM platform support is present, but
device support is absent). Unfortunate that this will be a vestigial
empty directory in the vast majority of cases.
* Reintroduce usage of runtime calls to sysfs_{create,remove}_group()
in the PCI core. Bjorn has already indicated that he does not want to
see any growth of pci_sysfs_init() [2].
* Drop the named group and simulate a directory by prefixing all
TSM-related attributes with "tsm_". Unfortunate to not use the naming
capability of a sysfs group as intended.
In comparison, there is a small potential for regression if for some
reason an @is_visible() callback had dependencies on how many times it
was called. Additionally, it is no longer an error to update a group
that does not have its directory already present, and it is no longer a
WARN() to remove a group that was never visible.
Link: https://lore.kernel.org/all/2024012321-envious-procedure-4a58@gregkh/ [1]
Link: https://lore.kernel.org/linux-pci/20231019200110.GA1410324@bhelgaas/ [2]
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/2024013028-deflator-flaring-ec62@gregkh
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-01-30 11:46:27 -07:00
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return grp->is_visible(kobj, grp->attrs[0], 0);
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2024-02-22 13:40:54 -07:00
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if (grp->bin_attrs && grp->bin_attrs[0] && grp->is_bin_visible)
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sysfs: Introduce a mechanism to hide static attribute_groups
Add a mechanism for named attribute_groups to hide their directory at
sysfs_update_group() time, or otherwise skip emitting the group
directory when the group is first registered. It piggybacks on
is_visible() in a similar manner as SYSFS_PREALLOC, i.e. special flags
in the upper bits of the returned mode. To use it, specify a symbol
prefix to DEFINE_SYSFS_GROUP_VISIBLE(), and then pass that same prefix
to SYSFS_GROUP_VISIBLE() when assigning the @is_visible() callback:
DEFINE_SYSFS_GROUP_VISIBLE($prefix)
struct attribute_group $prefix_group = {
.name = $name,
.is_visible = SYSFS_GROUP_VISIBLE($prefix),
};
SYSFS_GROUP_VISIBLE() expects a definition of $prefix_group_visible()
and $prefix_attr_visible(), where $prefix_group_visible() just returns
true / false and $prefix_attr_visible() behaves as normal.
The motivation for this capability is to centralize PCI device
authentication in the PCI core with a named sysfs group while keeping
that group hidden for devices and platforms that do not meet the
requirements. In a PCI topology, most devices will not support
authentication, a small subset will support just PCI CMA (Component
Measurement and Authentication), a smaller subset will support PCI CMA +
PCIe IDE (Link Integrity and Encryption), and only next generation
server hosts will start to include a platform TSM (TEE Security
Manager).
Without this capability the alternatives are:
* Check if all attributes are invisible and if so, hide the directory.
Beyond trouble getting this to work [1], this is an ABI change for
scenarios if userspace happens to depend on group visibility absent any
attributes. I.e. this new capability avoids regression since it does
not retroactively apply to existing cases.
* Publish an empty /sys/bus/pci/devices/$pdev/tsm/ directory for all PCI
devices (i.e. for the case when TSM platform support is present, but
device support is absent). Unfortunate that this will be a vestigial
empty directory in the vast majority of cases.
* Reintroduce usage of runtime calls to sysfs_{create,remove}_group()
in the PCI core. Bjorn has already indicated that he does not want to
see any growth of pci_sysfs_init() [2].
* Drop the named group and simulate a directory by prefixing all
TSM-related attributes with "tsm_". Unfortunate to not use the naming
capability of a sysfs group as intended.
In comparison, there is a small potential for regression if for some
reason an @is_visible() callback had dependencies on how many times it
was called. Additionally, it is no longer an error to update a group
that does not have its directory already present, and it is no longer a
WARN() to remove a group that was never visible.
Link: https://lore.kernel.org/all/2024012321-envious-procedure-4a58@gregkh/ [1]
Link: https://lore.kernel.org/linux-pci/20231019200110.GA1410324@bhelgaas/ [2]
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/2024013028-deflator-flaring-ec62@gregkh
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-01-30 11:46:27 -07:00
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return grp->is_bin_visible(kobj, grp->bin_attrs[0], 0);
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return 0;
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}
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2013-12-11 12:11:53 -07:00
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static int create_files(struct kernfs_node *parent, struct kobject *kobj,
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2018-07-20 14:56:48 -07:00
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kuid_t uid, kgid_t gid,
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2008-03-20 18:47:52 -07:00
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const struct attribute_group *grp, int update)
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2005-04-16 15:20:36 -07:00
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{
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2013-08-21 16:07:29 -07:00
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struct attribute *const *attr;
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struct bin_attribute *const *bin_attr;
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2007-10-31 07:38:04 -07:00
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int error = 0, i;
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2005-04-16 15:20:36 -07:00
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2013-07-14 16:05:55 -07:00
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if (grp->attrs) {
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for (i = 0, attr = grp->attrs; *attr && !error; i++, attr++) {
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2015-03-12 06:58:26 -07:00
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umode_t mode = (*attr)->mode;
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2008-03-20 18:47:52 -07:00
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2013-07-14 16:05:55 -07:00
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/*
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* In update mode, we're changing the permissions or
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* visibility. Do this by first removing then
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* re-adding (if required) the file.
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*/
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if (update)
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2013-12-11 12:11:53 -07:00
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kernfs_remove_by_name(parent, (*attr)->name);
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2013-07-14 16:05:55 -07:00
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if (grp->is_visible) {
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mode = grp->is_visible(kobj, *attr, i);
|
sysfs: Introduce a mechanism to hide static attribute_groups
Add a mechanism for named attribute_groups to hide their directory at
sysfs_update_group() time, or otherwise skip emitting the group
directory when the group is first registered. It piggybacks on
is_visible() in a similar manner as SYSFS_PREALLOC, i.e. special flags
in the upper bits of the returned mode. To use it, specify a symbol
prefix to DEFINE_SYSFS_GROUP_VISIBLE(), and then pass that same prefix
to SYSFS_GROUP_VISIBLE() when assigning the @is_visible() callback:
DEFINE_SYSFS_GROUP_VISIBLE($prefix)
struct attribute_group $prefix_group = {
.name = $name,
.is_visible = SYSFS_GROUP_VISIBLE($prefix),
};
SYSFS_GROUP_VISIBLE() expects a definition of $prefix_group_visible()
and $prefix_attr_visible(), where $prefix_group_visible() just returns
true / false and $prefix_attr_visible() behaves as normal.
The motivation for this capability is to centralize PCI device
authentication in the PCI core with a named sysfs group while keeping
that group hidden for devices and platforms that do not meet the
requirements. In a PCI topology, most devices will not support
authentication, a small subset will support just PCI CMA (Component
Measurement and Authentication), a smaller subset will support PCI CMA +
PCIe IDE (Link Integrity and Encryption), and only next generation
server hosts will start to include a platform TSM (TEE Security
Manager).
Without this capability the alternatives are:
* Check if all attributes are invisible and if so, hide the directory.
Beyond trouble getting this to work [1], this is an ABI change for
scenarios if userspace happens to depend on group visibility absent any
attributes. I.e. this new capability avoids regression since it does
not retroactively apply to existing cases.
* Publish an empty /sys/bus/pci/devices/$pdev/tsm/ directory for all PCI
devices (i.e. for the case when TSM platform support is present, but
device support is absent). Unfortunate that this will be a vestigial
empty directory in the vast majority of cases.
* Reintroduce usage of runtime calls to sysfs_{create,remove}_group()
in the PCI core. Bjorn has already indicated that he does not want to
see any growth of pci_sysfs_init() [2].
* Drop the named group and simulate a directory by prefixing all
TSM-related attributes with "tsm_". Unfortunate to not use the naming
capability of a sysfs group as intended.
In comparison, there is a small potential for regression if for some
reason an @is_visible() callback had dependencies on how many times it
was called. Additionally, it is no longer an error to update a group
that does not have its directory already present, and it is no longer a
WARN() to remove a group that was never visible.
Link: https://lore.kernel.org/all/2024012321-envious-procedure-4a58@gregkh/ [1]
Link: https://lore.kernel.org/linux-pci/20231019200110.GA1410324@bhelgaas/ [2]
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/2024013028-deflator-flaring-ec62@gregkh
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-01-30 11:46:27 -07:00
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mode &= ~SYSFS_GROUP_INVISIBLE;
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2013-07-14 16:05:55 -07:00
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if (!mode)
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continue;
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}
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2015-03-12 06:58:27 -07:00
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WARN(mode & ~(SYSFS_PREALLOC | 0664),
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"Attribute %s: Invalid permissions 0%o\n",
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(*attr)->name, mode);
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mode &= SYSFS_PREALLOC | 0664;
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2021-09-12 22:41:12 -07:00
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error = sysfs_add_file_mode_ns(parent, *attr, mode, uid,
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gid, NULL);
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2013-07-14 16:05:55 -07:00
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if (unlikely(error))
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break;
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}
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if (error) {
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2014-05-05 06:17:20 -07:00
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remove_files(parent, grp);
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2013-07-14 16:05:55 -07:00
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goto exit;
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}
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}
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if (grp->bin_attrs) {
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2015-09-21 06:38:20 -07:00
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for (i = 0, bin_attr = grp->bin_attrs; *bin_attr; i++, bin_attr++) {
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umode_t mode = (*bin_attr)->attr.mode;
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2013-07-14 16:05:55 -07:00
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if (update)
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2014-02-14 15:02:07 -07:00
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kernfs_remove_by_name(parent,
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(*bin_attr)->attr.name);
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2015-09-21 06:38:20 -07:00
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if (grp->is_bin_visible) {
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mode = grp->is_bin_visible(kobj, *bin_attr, i);
|
sysfs: Introduce a mechanism to hide static attribute_groups
Add a mechanism for named attribute_groups to hide their directory at
sysfs_update_group() time, or otherwise skip emitting the group
directory when the group is first registered. It piggybacks on
is_visible() in a similar manner as SYSFS_PREALLOC, i.e. special flags
in the upper bits of the returned mode. To use it, specify a symbol
prefix to DEFINE_SYSFS_GROUP_VISIBLE(), and then pass that same prefix
to SYSFS_GROUP_VISIBLE() when assigning the @is_visible() callback:
DEFINE_SYSFS_GROUP_VISIBLE($prefix)
struct attribute_group $prefix_group = {
.name = $name,
.is_visible = SYSFS_GROUP_VISIBLE($prefix),
};
SYSFS_GROUP_VISIBLE() expects a definition of $prefix_group_visible()
and $prefix_attr_visible(), where $prefix_group_visible() just returns
true / false and $prefix_attr_visible() behaves as normal.
The motivation for this capability is to centralize PCI device
authentication in the PCI core with a named sysfs group while keeping
that group hidden for devices and platforms that do not meet the
requirements. In a PCI topology, most devices will not support
authentication, a small subset will support just PCI CMA (Component
Measurement and Authentication), a smaller subset will support PCI CMA +
PCIe IDE (Link Integrity and Encryption), and only next generation
server hosts will start to include a platform TSM (TEE Security
Manager).
Without this capability the alternatives are:
* Check if all attributes are invisible and if so, hide the directory.
Beyond trouble getting this to work [1], this is an ABI change for
scenarios if userspace happens to depend on group visibility absent any
attributes. I.e. this new capability avoids regression since it does
not retroactively apply to existing cases.
* Publish an empty /sys/bus/pci/devices/$pdev/tsm/ directory for all PCI
devices (i.e. for the case when TSM platform support is present, but
device support is absent). Unfortunate that this will be a vestigial
empty directory in the vast majority of cases.
* Reintroduce usage of runtime calls to sysfs_{create,remove}_group()
in the PCI core. Bjorn has already indicated that he does not want to
see any growth of pci_sysfs_init() [2].
* Drop the named group and simulate a directory by prefixing all
TSM-related attributes with "tsm_". Unfortunate to not use the naming
capability of a sysfs group as intended.
In comparison, there is a small potential for regression if for some
reason an @is_visible() callback had dependencies on how many times it
was called. Additionally, it is no longer an error to update a group
that does not have its directory already present, and it is no longer a
WARN() to remove a group that was never visible.
Link: https://lore.kernel.org/all/2024012321-envious-procedure-4a58@gregkh/ [1]
Link: https://lore.kernel.org/linux-pci/20231019200110.GA1410324@bhelgaas/ [2]
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/2024013028-deflator-flaring-ec62@gregkh
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-01-30 11:46:27 -07:00
|
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|
mode &= ~SYSFS_GROUP_INVISIBLE;
|
2015-09-21 06:38:20 -07:00
|
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if (!mode)
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continue;
|
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}
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|
|
|
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WARN(mode & ~(SYSFS_PREALLOC | 0664),
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"Attribute %s: Invalid permissions 0%o\n",
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(*bin_attr)->attr.name, mode);
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mode &= SYSFS_PREALLOC | 0664;
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2021-09-12 22:41:12 -07:00
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error = sysfs_add_bin_file_mode_ns(parent, *bin_attr,
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mode, uid, gid,
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|
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NULL);
|
2013-07-14 16:05:55 -07:00
|
|
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if (error)
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break;
|
2008-03-20 18:47:52 -07:00
|
|
|
}
|
2013-07-14 16:05:55 -07:00
|
|
|
if (error)
|
2014-05-05 06:17:20 -07:00
|
|
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remove_files(parent, grp);
|
2008-03-20 18:47:52 -07:00
|
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}
|
2013-07-14 16:05:55 -07:00
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exit:
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2005-04-16 15:20:36 -07:00
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return error;
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}
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|
2008-03-20 18:47:52 -07:00
|
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static int internal_create_group(struct kobject *kobj, int update,
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|
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const struct attribute_group *grp)
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2005-04-16 15:20:36 -07:00
|
|
|
{
|
2013-12-11 12:11:53 -07:00
|
|
|
struct kernfs_node *kn;
|
2018-07-20 14:56:48 -07:00
|
|
|
kuid_t uid;
|
|
|
|
kgid_t gid;
|
2005-04-16 15:20:36 -07:00
|
|
|
int error;
|
|
|
|
|
2019-01-03 02:23:47 -07:00
|
|
|
if (WARN_ON(!kobj || (!update && !kobj->sd)))
|
|
|
|
return -EINVAL;
|
2008-03-20 18:47:52 -07:00
|
|
|
|
|
|
|
/* Updates may happen before the object has been instantiated */
|
|
|
|
if (unlikely(update && !kobj->sd))
|
|
|
|
return -EINVAL;
|
sysfs: Skip empty folders creation
Most sysfs attributes are statically defined, the goal with this design
being to be able to move all the filesystem description into read-only
memory. Anyway, it may be relevant in some cases to populate attributes
at run time. This leads to situation where an attribute may or may not be
present depending on conditions which are not known at compile
time, up to the point where no attribute at all gets added in a folder
which then becomes "sometimes" empty. Problem is, providing an attribute
group with a name and without .[bin_]attrs members will be loudly
refused by the core, leading in most cases to a device registration
failure.
The simple way to support such situation right now is to dynamically
allocate an empty attribute array, which is:
* a (small) waste of space
* a waste of time
* disturbing, to say the least, as an empty sysfs folder will be created
anyway.
Another (even worse) possibility would be to dynamically overwrite a
member of the attribute_group list, hopefully the last, which is also
supposed to remain in the read-only section.
In order to avoid these hackish situations, while still giving a little
bit of flexibility, we might just check the validity of the .[bin_]attrs
list and, if empty, just skip the attribute group creation instead of
failing. This way, developers will not be tempted to workaround the
core with useless allocations or strange writes on supposedly read-only
structures.
The content of the WARN() message is kept but turned into a debug
message in order to help developers understanding why their sysfs
folders might now silently fail to be created.
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Message-ID: <20230614063018.2419043-3-miquel.raynal@bootlin.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-13 23:30:16 -07:00
|
|
|
|
2013-07-14 16:05:56 -07:00
|
|
|
if (!grp->attrs && !grp->bin_attrs) {
|
sysfs: Skip empty folders creation
Most sysfs attributes are statically defined, the goal with this design
being to be able to move all the filesystem description into read-only
memory. Anyway, it may be relevant in some cases to populate attributes
at run time. This leads to situation where an attribute may or may not be
present depending on conditions which are not known at compile
time, up to the point where no attribute at all gets added in a folder
which then becomes "sometimes" empty. Problem is, providing an attribute
group with a name and without .[bin_]attrs members will be loudly
refused by the core, leading in most cases to a device registration
failure.
The simple way to support such situation right now is to dynamically
allocate an empty attribute array, which is:
* a (small) waste of space
* a waste of time
* disturbing, to say the least, as an empty sysfs folder will be created
anyway.
Another (even worse) possibility would be to dynamically overwrite a
member of the attribute_group list, hopefully the last, which is also
supposed to remain in the read-only section.
In order to avoid these hackish situations, while still giving a little
bit of flexibility, we might just check the validity of the .[bin_]attrs
list and, if empty, just skip the attribute group creation instead of
failing. This way, developers will not be tempted to workaround the
core with useless allocations or strange writes on supposedly read-only
structures.
The content of the WARN() message is kept but turned into a debug
message in order to help developers understanding why their sysfs
folders might now silently fail to be created.
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Message-ID: <20230614063018.2419043-3-miquel.raynal@bootlin.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-13 23:30:16 -07:00
|
|
|
pr_debug("sysfs: (bin_)attrs not set by subsystem for group: %s/%s, skipping\n",
|
|
|
|
kobj->name, grp->name ?: "");
|
|
|
|
return 0;
|
2012-04-03 00:59:48 -07:00
|
|
|
}
|
sysfs: Skip empty folders creation
Most sysfs attributes are statically defined, the goal with this design
being to be able to move all the filesystem description into read-only
memory. Anyway, it may be relevant in some cases to populate attributes
at run time. This leads to situation where an attribute may or may not be
present depending on conditions which are not known at compile
time, up to the point where no attribute at all gets added in a folder
which then becomes "sometimes" empty. Problem is, providing an attribute
group with a name and without .[bin_]attrs members will be loudly
refused by the core, leading in most cases to a device registration
failure.
The simple way to support such situation right now is to dynamically
allocate an empty attribute array, which is:
* a (small) waste of space
* a waste of time
* disturbing, to say the least, as an empty sysfs folder will be created
anyway.
Another (even worse) possibility would be to dynamically overwrite a
member of the attribute_group list, hopefully the last, which is also
supposed to remain in the read-only section.
In order to avoid these hackish situations, while still giving a little
bit of flexibility, we might just check the validity of the .[bin_]attrs
list and, if empty, just skip the attribute group creation instead of
failing. This way, developers will not be tempted to workaround the
core with useless allocations or strange writes on supposedly read-only
structures.
The content of the WARN() message is kept but turned into a debug
message in order to help developers understanding why their sysfs
folders might now silently fail to be created.
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Message-ID: <20230614063018.2419043-3-miquel.raynal@bootlin.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-13 23:30:16 -07:00
|
|
|
|
2018-07-20 14:56:48 -07:00
|
|
|
kobject_get_ownership(kobj, &uid, &gid);
|
2005-04-16 15:20:36 -07:00
|
|
|
if (grp->name) {
|
sysfs: Introduce a mechanism to hide static attribute_groups
Add a mechanism for named attribute_groups to hide their directory at
sysfs_update_group() time, or otherwise skip emitting the group
directory when the group is first registered. It piggybacks on
is_visible() in a similar manner as SYSFS_PREALLOC, i.e. special flags
in the upper bits of the returned mode. To use it, specify a symbol
prefix to DEFINE_SYSFS_GROUP_VISIBLE(), and then pass that same prefix
to SYSFS_GROUP_VISIBLE() when assigning the @is_visible() callback:
DEFINE_SYSFS_GROUP_VISIBLE($prefix)
struct attribute_group $prefix_group = {
.name = $name,
.is_visible = SYSFS_GROUP_VISIBLE($prefix),
};
SYSFS_GROUP_VISIBLE() expects a definition of $prefix_group_visible()
and $prefix_attr_visible(), where $prefix_group_visible() just returns
true / false and $prefix_attr_visible() behaves as normal.
The motivation for this capability is to centralize PCI device
authentication in the PCI core with a named sysfs group while keeping
that group hidden for devices and platforms that do not meet the
requirements. In a PCI topology, most devices will not support
authentication, a small subset will support just PCI CMA (Component
Measurement and Authentication), a smaller subset will support PCI CMA +
PCIe IDE (Link Integrity and Encryption), and only next generation
server hosts will start to include a platform TSM (TEE Security
Manager).
Without this capability the alternatives are:
* Check if all attributes are invisible and if so, hide the directory.
Beyond trouble getting this to work [1], this is an ABI change for
scenarios if userspace happens to depend on group visibility absent any
attributes. I.e. this new capability avoids regression since it does
not retroactively apply to existing cases.
* Publish an empty /sys/bus/pci/devices/$pdev/tsm/ directory for all PCI
devices (i.e. for the case when TSM platform support is present, but
device support is absent). Unfortunate that this will be a vestigial
empty directory in the vast majority of cases.
* Reintroduce usage of runtime calls to sysfs_{create,remove}_group()
in the PCI core. Bjorn has already indicated that he does not want to
see any growth of pci_sysfs_init() [2].
* Drop the named group and simulate a directory by prefixing all
TSM-related attributes with "tsm_". Unfortunate to not use the naming
capability of a sysfs group as intended.
In comparison, there is a small potential for regression if for some
reason an @is_visible() callback had dependencies on how many times it
was called. Additionally, it is no longer an error to update a group
that does not have its directory already present, and it is no longer a
WARN() to remove a group that was never visible.
Link: https://lore.kernel.org/all/2024012321-envious-procedure-4a58@gregkh/ [1]
Link: https://lore.kernel.org/linux-pci/20231019200110.GA1410324@bhelgaas/ [2]
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/2024013028-deflator-flaring-ec62@gregkh
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-01-30 11:46:27 -07:00
|
|
|
umode_t mode = __first_visible(grp, kobj);
|
|
|
|
|
|
|
|
if (mode & SYSFS_GROUP_INVISIBLE)
|
|
|
|
mode = 0;
|
|
|
|
else
|
|
|
|
mode = S_IRWXU | S_IRUGO | S_IXUGO;
|
|
|
|
|
2018-06-16 10:49:46 -07:00
|
|
|
if (update) {
|
|
|
|
kn = kernfs_find_and_get(kobj->sd, grp->name);
|
|
|
|
if (!kn) {
|
sysfs: Introduce a mechanism to hide static attribute_groups
Add a mechanism for named attribute_groups to hide their directory at
sysfs_update_group() time, or otherwise skip emitting the group
directory when the group is first registered. It piggybacks on
is_visible() in a similar manner as SYSFS_PREALLOC, i.e. special flags
in the upper bits of the returned mode. To use it, specify a symbol
prefix to DEFINE_SYSFS_GROUP_VISIBLE(), and then pass that same prefix
to SYSFS_GROUP_VISIBLE() when assigning the @is_visible() callback:
DEFINE_SYSFS_GROUP_VISIBLE($prefix)
struct attribute_group $prefix_group = {
.name = $name,
.is_visible = SYSFS_GROUP_VISIBLE($prefix),
};
SYSFS_GROUP_VISIBLE() expects a definition of $prefix_group_visible()
and $prefix_attr_visible(), where $prefix_group_visible() just returns
true / false and $prefix_attr_visible() behaves as normal.
The motivation for this capability is to centralize PCI device
authentication in the PCI core with a named sysfs group while keeping
that group hidden for devices and platforms that do not meet the
requirements. In a PCI topology, most devices will not support
authentication, a small subset will support just PCI CMA (Component
Measurement and Authentication), a smaller subset will support PCI CMA +
PCIe IDE (Link Integrity and Encryption), and only next generation
server hosts will start to include a platform TSM (TEE Security
Manager).
Without this capability the alternatives are:
* Check if all attributes are invisible and if so, hide the directory.
Beyond trouble getting this to work [1], this is an ABI change for
scenarios if userspace happens to depend on group visibility absent any
attributes. I.e. this new capability avoids regression since it does
not retroactively apply to existing cases.
* Publish an empty /sys/bus/pci/devices/$pdev/tsm/ directory for all PCI
devices (i.e. for the case when TSM platform support is present, but
device support is absent). Unfortunate that this will be a vestigial
empty directory in the vast majority of cases.
* Reintroduce usage of runtime calls to sysfs_{create,remove}_group()
in the PCI core. Bjorn has already indicated that he does not want to
see any growth of pci_sysfs_init() [2].
* Drop the named group and simulate a directory by prefixing all
TSM-related attributes with "tsm_". Unfortunate to not use the naming
capability of a sysfs group as intended.
In comparison, there is a small potential for regression if for some
reason an @is_visible() callback had dependencies on how many times it
was called. Additionally, it is no longer an error to update a group
that does not have its directory already present, and it is no longer a
WARN() to remove a group that was never visible.
Link: https://lore.kernel.org/all/2024012321-envious-procedure-4a58@gregkh/ [1]
Link: https://lore.kernel.org/linux-pci/20231019200110.GA1410324@bhelgaas/ [2]
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/2024013028-deflator-flaring-ec62@gregkh
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-01-30 11:46:27 -07:00
|
|
|
pr_debug("attr grp %s/%s not created yet\n",
|
|
|
|
kobj->name, grp->name);
|
|
|
|
/* may have been invisible prior to this update */
|
|
|
|
update = 0;
|
|
|
|
} else if (!mode) {
|
|
|
|
sysfs_remove_group(kobj, grp);
|
|
|
|
kernfs_put(kn);
|
|
|
|
return 0;
|
2018-06-16 10:49:46 -07:00
|
|
|
}
|
sysfs: Introduce a mechanism to hide static attribute_groups
Add a mechanism for named attribute_groups to hide their directory at
sysfs_update_group() time, or otherwise skip emitting the group
directory when the group is first registered. It piggybacks on
is_visible() in a similar manner as SYSFS_PREALLOC, i.e. special flags
in the upper bits of the returned mode. To use it, specify a symbol
prefix to DEFINE_SYSFS_GROUP_VISIBLE(), and then pass that same prefix
to SYSFS_GROUP_VISIBLE() when assigning the @is_visible() callback:
DEFINE_SYSFS_GROUP_VISIBLE($prefix)
struct attribute_group $prefix_group = {
.name = $name,
.is_visible = SYSFS_GROUP_VISIBLE($prefix),
};
SYSFS_GROUP_VISIBLE() expects a definition of $prefix_group_visible()
and $prefix_attr_visible(), where $prefix_group_visible() just returns
true / false and $prefix_attr_visible() behaves as normal.
The motivation for this capability is to centralize PCI device
authentication in the PCI core with a named sysfs group while keeping
that group hidden for devices and platforms that do not meet the
requirements. In a PCI topology, most devices will not support
authentication, a small subset will support just PCI CMA (Component
Measurement and Authentication), a smaller subset will support PCI CMA +
PCIe IDE (Link Integrity and Encryption), and only next generation
server hosts will start to include a platform TSM (TEE Security
Manager).
Without this capability the alternatives are:
* Check if all attributes are invisible and if so, hide the directory.
Beyond trouble getting this to work [1], this is an ABI change for
scenarios if userspace happens to depend on group visibility absent any
attributes. I.e. this new capability avoids regression since it does
not retroactively apply to existing cases.
* Publish an empty /sys/bus/pci/devices/$pdev/tsm/ directory for all PCI
devices (i.e. for the case when TSM platform support is present, but
device support is absent). Unfortunate that this will be a vestigial
empty directory in the vast majority of cases.
* Reintroduce usage of runtime calls to sysfs_{create,remove}_group()
in the PCI core. Bjorn has already indicated that he does not want to
see any growth of pci_sysfs_init() [2].
* Drop the named group and simulate a directory by prefixing all
TSM-related attributes with "tsm_". Unfortunate to not use the naming
capability of a sysfs group as intended.
In comparison, there is a small potential for regression if for some
reason an @is_visible() callback had dependencies on how many times it
was called. Additionally, it is no longer an error to update a group
that does not have its directory already present, and it is no longer a
WARN() to remove a group that was never visible.
Link: https://lore.kernel.org/all/2024012321-envious-procedure-4a58@gregkh/ [1]
Link: https://lore.kernel.org/linux-pci/20231019200110.GA1410324@bhelgaas/ [2]
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/2024013028-deflator-flaring-ec62@gregkh
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-01-30 11:46:27 -07:00
|
|
|
}
|
|
|
|
|
|
|
|
if (!update) {
|
|
|
|
if (!mode)
|
|
|
|
return 0;
|
|
|
|
kn = kernfs_create_dir_ns(kobj->sd, grp->name, mode,
|
2018-08-18 11:44:53 -07:00
|
|
|
uid, gid, kobj, NULL);
|
2018-06-16 10:49:46 -07:00
|
|
|
if (IS_ERR(kn)) {
|
|
|
|
if (PTR_ERR(kn) == -EEXIST)
|
|
|
|
sysfs_warn_dup(kobj->sd, grp->name);
|
|
|
|
return PTR_ERR(kn);
|
|
|
|
}
|
2013-11-28 12:54:15 -07:00
|
|
|
}
|
2023-06-13 23:30:15 -07:00
|
|
|
} else {
|
2013-12-11 12:11:53 -07:00
|
|
|
kn = kobj->sd;
|
2023-06-13 23:30:15 -07:00
|
|
|
}
|
|
|
|
|
2013-12-11 12:11:53 -07:00
|
|
|
kernfs_get(kn);
|
2018-07-20 14:56:48 -07:00
|
|
|
error = create_files(kn, kobj, uid, gid, grp, update);
|
2007-06-13 12:27:22 -07:00
|
|
|
if (error) {
|
2005-04-16 15:20:36 -07:00
|
|
|
if (grp->name)
|
2013-12-11 12:11:53 -07:00
|
|
|
kernfs_remove(kn);
|
2005-04-16 15:20:36 -07:00
|
|
|
}
|
2013-12-11 12:11:53 -07:00
|
|
|
kernfs_put(kn);
|
2018-06-16 10:49:46 -07:00
|
|
|
|
|
|
|
if (grp->name && update)
|
|
|
|
kernfs_put(kn);
|
|
|
|
|
2005-04-16 15:20:36 -07:00
|
|
|
return error;
|
|
|
|
}
|
|
|
|
|
2008-03-20 18:47:52 -07:00
|
|
|
/**
|
|
|
|
* sysfs_create_group - given a directory kobject, create an attribute group
|
|
|
|
* @kobj: The kobject to create the group on
|
|
|
|
* @grp: The attribute group to create
|
|
|
|
*
|
|
|
|
* This function creates a group for the first time. It will explicitly
|
|
|
|
* warn and error if any of the attribute files being created already exist.
|
|
|
|
*
|
2015-04-29 01:55:46 -07:00
|
|
|
* Returns 0 on success or error code on failure.
|
2008-03-20 18:47:52 -07:00
|
|
|
*/
|
|
|
|
int sysfs_create_group(struct kobject *kobj,
|
|
|
|
const struct attribute_group *grp)
|
|
|
|
{
|
|
|
|
return internal_create_group(kobj, 0, grp);
|
|
|
|
}
|
2013-08-21 16:04:12 -07:00
|
|
|
EXPORT_SYMBOL_GPL(sysfs_create_group);
|
2008-03-20 18:47:52 -07:00
|
|
|
|
2019-05-12 08:55:10 -07:00
|
|
|
static int internal_create_groups(struct kobject *kobj, int update,
|
|
|
|
const struct attribute_group **groups)
|
|
|
|
{
|
|
|
|
int error = 0;
|
|
|
|
int i;
|
|
|
|
|
|
|
|
if (!groups)
|
|
|
|
return 0;
|
|
|
|
|
|
|
|
for (i = 0; groups[i]; i++) {
|
|
|
|
error = internal_create_group(kobj, update, groups[i]);
|
|
|
|
if (error) {
|
|
|
|
while (--i >= 0)
|
|
|
|
sysfs_remove_group(kobj, groups[i]);
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
return error;
|
|
|
|
}
|
|
|
|
|
2013-08-21 13:47:50 -07:00
|
|
|
/**
|
|
|
|
* sysfs_create_groups - given a directory kobject, create a bunch of attribute groups
|
|
|
|
* @kobj: The kobject to create the group on
|
|
|
|
* @groups: The attribute groups to create, NULL terminated
|
|
|
|
*
|
|
|
|
* This function creates a bunch of attribute groups. If an error occurs when
|
|
|
|
* creating a group, all previously created groups will be removed, unwinding
|
|
|
|
* everything back to the original state when this function was called.
|
|
|
|
* It will explicitly warn and error if any of the attribute files being
|
|
|
|
* created already exist.
|
|
|
|
*
|
2015-04-29 01:55:46 -07:00
|
|
|
* Returns 0 on success or error code from sysfs_create_group on failure.
|
2013-08-21 13:47:50 -07:00
|
|
|
*/
|
|
|
|
int sysfs_create_groups(struct kobject *kobj,
|
|
|
|
const struct attribute_group **groups)
|
|
|
|
{
|
2019-05-12 08:55:10 -07:00
|
|
|
return internal_create_groups(kobj, 0, groups);
|
2013-08-21 13:47:50 -07:00
|
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(sysfs_create_groups);
|
|
|
|
|
2019-05-12 08:55:10 -07:00
|
|
|
/**
|
|
|
|
* sysfs_update_groups - given a directory kobject, create a bunch of attribute groups
|
|
|
|
* @kobj: The kobject to update the group on
|
|
|
|
* @groups: The attribute groups to update, NULL terminated
|
|
|
|
*
|
|
|
|
* This function update a bunch of attribute groups. If an error occurs when
|
|
|
|
* updating a group, all previously updated groups will be removed together
|
|
|
|
* with already existing (not updated) attributes.
|
|
|
|
*
|
|
|
|
* Returns 0 on success or error code from sysfs_update_group on failure.
|
|
|
|
*/
|
|
|
|
int sysfs_update_groups(struct kobject *kobj,
|
|
|
|
const struct attribute_group **groups)
|
|
|
|
{
|
|
|
|
return internal_create_groups(kobj, 1, groups);
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(sysfs_update_groups);
|
|
|
|
|
2008-03-20 18:47:52 -07:00
|
|
|
/**
|
2011-05-07 14:18:20 -07:00
|
|
|
* sysfs_update_group - given a directory kobject, update an attribute group
|
|
|
|
* @kobj: The kobject to update the group on
|
|
|
|
* @grp: The attribute group to update
|
2008-03-20 18:47:52 -07:00
|
|
|
*
|
|
|
|
* This function updates an attribute group. Unlike
|
|
|
|
* sysfs_create_group(), it will explicitly not warn or error if any
|
|
|
|
* of the attribute files being created already exist. Furthermore,
|
|
|
|
* if the visibility of the files has changed through the is_visible()
|
|
|
|
* callback, it will update the permissions and add or remove the
|
2018-06-16 10:49:46 -07:00
|
|
|
* relevant files. Changing a group's name (subdirectory name under
|
|
|
|
* kobj's directory in sysfs) is not allowed.
|
2008-03-20 18:47:52 -07:00
|
|
|
*
|
|
|
|
* The primary use for this function is to call it after making a change
|
|
|
|
* that affects group visibility.
|
|
|
|
*
|
2015-04-29 01:55:46 -07:00
|
|
|
* Returns 0 on success or error code on failure.
|
2008-03-20 18:47:52 -07:00
|
|
|
*/
|
|
|
|
int sysfs_update_group(struct kobject *kobj,
|
|
|
|
const struct attribute_group *grp)
|
|
|
|
{
|
|
|
|
return internal_create_group(kobj, 1, grp);
|
|
|
|
}
|
2013-08-21 16:04:12 -07:00
|
|
|
EXPORT_SYMBOL_GPL(sysfs_update_group);
|
2008-03-20 18:47:52 -07:00
|
|
|
|
2013-08-21 16:12:34 -07:00
|
|
|
/**
|
|
|
|
* sysfs_remove_group: remove a group from a kobject
|
|
|
|
* @kobj: kobject to remove the group from
|
|
|
|
* @grp: group to remove
|
|
|
|
*
|
|
|
|
* This function removes a group of attributes from a kobject. The attributes
|
|
|
|
* previously have to have been created for this group, otherwise it will fail.
|
|
|
|
*/
|
2013-08-21 16:07:29 -07:00
|
|
|
void sysfs_remove_group(struct kobject *kobj,
|
|
|
|
const struct attribute_group *grp)
|
2005-04-16 15:20:36 -07:00
|
|
|
{
|
2013-12-11 12:11:53 -07:00
|
|
|
struct kernfs_node *parent = kobj->sd;
|
|
|
|
struct kernfs_node *kn;
|
2005-04-16 15:20:36 -07:00
|
|
|
|
2007-04-26 00:12:05 -07:00
|
|
|
if (grp->name) {
|
2013-12-11 12:11:53 -07:00
|
|
|
kn = kernfs_find_and_get(parent, grp->name);
|
|
|
|
if (!kn) {
|
sysfs: Introduce a mechanism to hide static attribute_groups
Add a mechanism for named attribute_groups to hide their directory at
sysfs_update_group() time, or otherwise skip emitting the group
directory when the group is first registered. It piggybacks on
is_visible() in a similar manner as SYSFS_PREALLOC, i.e. special flags
in the upper bits of the returned mode. To use it, specify a symbol
prefix to DEFINE_SYSFS_GROUP_VISIBLE(), and then pass that same prefix
to SYSFS_GROUP_VISIBLE() when assigning the @is_visible() callback:
DEFINE_SYSFS_GROUP_VISIBLE($prefix)
struct attribute_group $prefix_group = {
.name = $name,
.is_visible = SYSFS_GROUP_VISIBLE($prefix),
};
SYSFS_GROUP_VISIBLE() expects a definition of $prefix_group_visible()
and $prefix_attr_visible(), where $prefix_group_visible() just returns
true / false and $prefix_attr_visible() behaves as normal.
The motivation for this capability is to centralize PCI device
authentication in the PCI core with a named sysfs group while keeping
that group hidden for devices and platforms that do not meet the
requirements. In a PCI topology, most devices will not support
authentication, a small subset will support just PCI CMA (Component
Measurement and Authentication), a smaller subset will support PCI CMA +
PCIe IDE (Link Integrity and Encryption), and only next generation
server hosts will start to include a platform TSM (TEE Security
Manager).
Without this capability the alternatives are:
* Check if all attributes are invisible and if so, hide the directory.
Beyond trouble getting this to work [1], this is an ABI change for
scenarios if userspace happens to depend on group visibility absent any
attributes. I.e. this new capability avoids regression since it does
not retroactively apply to existing cases.
* Publish an empty /sys/bus/pci/devices/$pdev/tsm/ directory for all PCI
devices (i.e. for the case when TSM platform support is present, but
device support is absent). Unfortunate that this will be a vestigial
empty directory in the vast majority of cases.
* Reintroduce usage of runtime calls to sysfs_{create,remove}_group()
in the PCI core. Bjorn has already indicated that he does not want to
see any growth of pci_sysfs_init() [2].
* Drop the named group and simulate a directory by prefixing all
TSM-related attributes with "tsm_". Unfortunate to not use the naming
capability of a sysfs group as intended.
In comparison, there is a small potential for regression if for some
reason an @is_visible() callback had dependencies on how many times it
was called. Additionally, it is no longer an error to update a group
that does not have its directory already present, and it is no longer a
WARN() to remove a group that was never visible.
Link: https://lore.kernel.org/all/2024012321-envious-procedure-4a58@gregkh/ [1]
Link: https://lore.kernel.org/linux-pci/20231019200110.GA1410324@bhelgaas/ [2]
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/2024013028-deflator-flaring-ec62@gregkh
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-01-30 11:46:27 -07:00
|
|
|
pr_debug("sysfs group '%s' not found for kobject '%s'\n",
|
|
|
|
grp->name, kobject_name(kobj));
|
2008-02-07 09:58:54 -07:00
|
|
|
return;
|
|
|
|
}
|
2013-11-28 12:54:30 -07:00
|
|
|
} else {
|
2013-12-11 12:11:53 -07:00
|
|
|
kn = parent;
|
|
|
|
kernfs_get(kn);
|
2013-11-28 12:54:30 -07:00
|
|
|
}
|
2005-04-16 15:20:36 -07:00
|
|
|
|
2014-05-05 06:17:20 -07:00
|
|
|
remove_files(kn, grp);
|
2005-04-16 15:20:36 -07:00
|
|
|
if (grp->name)
|
2013-12-11 12:11:53 -07:00
|
|
|
kernfs_remove(kn);
|
2007-06-13 12:27:22 -07:00
|
|
|
|
2013-12-11 12:11:53 -07:00
|
|
|
kernfs_put(kn);
|
2005-04-16 15:20:36 -07:00
|
|
|
}
|
2013-08-21 16:04:12 -07:00
|
|
|
EXPORT_SYMBOL_GPL(sysfs_remove_group);
|
2005-04-16 15:20:36 -07:00
|
|
|
|
2013-08-21 13:47:50 -07:00
|
|
|
/**
|
|
|
|
* sysfs_remove_groups - remove a list of groups
|
|
|
|
*
|
2013-08-21 16:12:34 -07:00
|
|
|
* @kobj: The kobject for the groups to be removed from
|
|
|
|
* @groups: NULL terminated list of groups to be removed
|
2013-08-21 13:47:50 -07:00
|
|
|
*
|
2013-08-22 09:23:28 -07:00
|
|
|
* If groups is not NULL, remove the specified groups from the kobject.
|
2013-08-21 13:47:50 -07:00
|
|
|
*/
|
|
|
|
void sysfs_remove_groups(struct kobject *kobj,
|
|
|
|
const struct attribute_group **groups)
|
|
|
|
{
|
|
|
|
int i;
|
|
|
|
|
|
|
|
if (!groups)
|
|
|
|
return;
|
|
|
|
for (i = 0; groups[i]; i++)
|
|
|
|
sysfs_remove_group(kobj, groups[i]);
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(sysfs_remove_groups);
|
|
|
|
|
2010-09-25 14:34:22 -07:00
|
|
|
/**
|
2024-02-11 15:36:34 -07:00
|
|
|
* sysfs_merge_group - merge files into a pre-existing named attribute group.
|
2010-09-25 14:34:22 -07:00
|
|
|
* @kobj: The kobject containing the group.
|
|
|
|
* @grp: The files to create and the attribute group they belong to.
|
|
|
|
*
|
2024-02-11 15:36:34 -07:00
|
|
|
* This function returns an error if the group doesn't exist, the .name field is
|
|
|
|
* NULL or any of the files already exist in that group, in which case none of
|
|
|
|
* the new files are created.
|
2010-09-25 14:34:22 -07:00
|
|
|
*/
|
|
|
|
int sysfs_merge_group(struct kobject *kobj,
|
|
|
|
const struct attribute_group *grp)
|
|
|
|
{
|
2013-12-11 12:11:53 -07:00
|
|
|
struct kernfs_node *parent;
|
2018-07-20 14:56:48 -07:00
|
|
|
kuid_t uid;
|
|
|
|
kgid_t gid;
|
2010-09-25 14:34:22 -07:00
|
|
|
int error = 0;
|
|
|
|
struct attribute *const *attr;
|
|
|
|
int i;
|
|
|
|
|
2013-12-11 12:11:53 -07:00
|
|
|
parent = kernfs_find_and_get(kobj->sd, grp->name);
|
|
|
|
if (!parent)
|
2010-09-25 14:34:22 -07:00
|
|
|
return -ENOENT;
|
|
|
|
|
2018-07-20 14:56:48 -07:00
|
|
|
kobject_get_ownership(kobj, &uid, &gid);
|
|
|
|
|
2010-09-25 14:34:22 -07:00
|
|
|
for ((i = 0, attr = grp->attrs); *attr && !error; (++i, ++attr))
|
2021-09-12 22:41:12 -07:00
|
|
|
error = sysfs_add_file_mode_ns(parent, *attr, (*attr)->mode,
|
|
|
|
uid, gid, NULL);
|
2010-09-25 14:34:22 -07:00
|
|
|
if (error) {
|
|
|
|
while (--i >= 0)
|
2013-12-11 12:11:53 -07:00
|
|
|
kernfs_remove_by_name(parent, (*--attr)->name);
|
2010-09-25 14:34:22 -07:00
|
|
|
}
|
2013-12-11 12:11:53 -07:00
|
|
|
kernfs_put(parent);
|
2010-09-25 14:34:22 -07:00
|
|
|
|
|
|
|
return error;
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(sysfs_merge_group);
|
|
|
|
|
|
|
|
/**
|
2024-02-11 15:36:34 -07:00
|
|
|
* sysfs_unmerge_group - remove files from a pre-existing named attribute group.
|
2010-09-25 14:34:22 -07:00
|
|
|
* @kobj: The kobject containing the group.
|
|
|
|
* @grp: The files to remove and the attribute group they belong to.
|
|
|
|
*/
|
|
|
|
void sysfs_unmerge_group(struct kobject *kobj,
|
|
|
|
const struct attribute_group *grp)
|
|
|
|
{
|
2013-12-11 12:11:53 -07:00
|
|
|
struct kernfs_node *parent;
|
2010-09-25 14:34:22 -07:00
|
|
|
struct attribute *const *attr;
|
|
|
|
|
2013-12-11 12:11:53 -07:00
|
|
|
parent = kernfs_find_and_get(kobj->sd, grp->name);
|
|
|
|
if (parent) {
|
2010-09-25 14:34:22 -07:00
|
|
|
for (attr = grp->attrs; *attr; ++attr)
|
2013-12-11 12:11:53 -07:00
|
|
|
kernfs_remove_by_name(parent, (*attr)->name);
|
|
|
|
kernfs_put(parent);
|
2010-09-25 14:34:22 -07:00
|
|
|
}
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(sysfs_unmerge_group);
|
|
|
|
|
2013-01-25 13:51:13 -07:00
|
|
|
/**
|
|
|
|
* sysfs_add_link_to_group - add a symlink to an attribute group.
|
|
|
|
* @kobj: The kobject containing the group.
|
|
|
|
* @group_name: The name of the group.
|
|
|
|
* @target: The target kobject of the symlink to create.
|
|
|
|
* @link_name: The name of the symlink to create.
|
|
|
|
*/
|
|
|
|
int sysfs_add_link_to_group(struct kobject *kobj, const char *group_name,
|
|
|
|
struct kobject *target, const char *link_name)
|
|
|
|
{
|
2013-12-11 12:11:53 -07:00
|
|
|
struct kernfs_node *parent;
|
2013-01-25 13:51:13 -07:00
|
|
|
int error = 0;
|
|
|
|
|
2013-12-11 12:11:53 -07:00
|
|
|
parent = kernfs_find_and_get(kobj->sd, group_name);
|
|
|
|
if (!parent)
|
2013-01-25 13:51:13 -07:00
|
|
|
return -ENOENT;
|
|
|
|
|
2013-12-11 12:11:53 -07:00
|
|
|
error = sysfs_create_link_sd(parent, target, link_name);
|
|
|
|
kernfs_put(parent);
|
2013-01-25 13:51:13 -07:00
|
|
|
|
|
|
|
return error;
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(sysfs_add_link_to_group);
|
|
|
|
|
|
|
|
/**
|
|
|
|
* sysfs_remove_link_from_group - remove a symlink from an attribute group.
|
|
|
|
* @kobj: The kobject containing the group.
|
|
|
|
* @group_name: The name of the group.
|
|
|
|
* @link_name: The name of the symlink to remove.
|
|
|
|
*/
|
|
|
|
void sysfs_remove_link_from_group(struct kobject *kobj, const char *group_name,
|
|
|
|
const char *link_name)
|
|
|
|
{
|
2013-12-11 12:11:53 -07:00
|
|
|
struct kernfs_node *parent;
|
2013-01-25 13:51:13 -07:00
|
|
|
|
2013-12-11 12:11:53 -07:00
|
|
|
parent = kernfs_find_and_get(kobj->sd, group_name);
|
|
|
|
if (parent) {
|
|
|
|
kernfs_remove_by_name(parent, link_name);
|
|
|
|
kernfs_put(parent);
|
2013-01-25 13:51:13 -07:00
|
|
|
}
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(sysfs_remove_link_from_group);
|
2015-04-22 09:36:06 -07:00
|
|
|
|
2019-12-11 09:09:06 -07:00
|
|
|
/**
|
|
|
|
* compat_only_sysfs_link_entry_to_kobj - add a symlink to a kobject pointing
|
|
|
|
* to a group or an attribute
|
|
|
|
* @kobj: The kobject containing the group.
|
|
|
|
* @target_kobj: The target kobject.
|
|
|
|
* @target_name: The name of the target group or attribute.
|
|
|
|
* @symlink_name: The name of the symlink file (target_name will be
|
|
|
|
* considered if symlink_name is NULL).
|
|
|
|
*/
|
|
|
|
int compat_only_sysfs_link_entry_to_kobj(struct kobject *kobj,
|
|
|
|
struct kobject *target_kobj,
|
|
|
|
const char *target_name,
|
|
|
|
const char *symlink_name)
|
2015-04-22 09:36:06 -07:00
|
|
|
{
|
|
|
|
struct kernfs_node *target;
|
|
|
|
struct kernfs_node *entry;
|
|
|
|
struct kernfs_node *link;
|
|
|
|
|
|
|
|
/*
|
|
|
|
* We don't own @target_kobj and it may be removed at any time.
|
|
|
|
* Synchronize using sysfs_symlink_target_lock. See sysfs_remove_dir()
|
|
|
|
* for details.
|
|
|
|
*/
|
|
|
|
spin_lock(&sysfs_symlink_target_lock);
|
|
|
|
target = target_kobj->sd;
|
|
|
|
if (target)
|
|
|
|
kernfs_get(target);
|
|
|
|
spin_unlock(&sysfs_symlink_target_lock);
|
|
|
|
if (!target)
|
|
|
|
return -ENOENT;
|
|
|
|
|
2021-07-14 08:15:59 -07:00
|
|
|
entry = kernfs_find_and_get(target, target_name);
|
2015-04-22 09:36:06 -07:00
|
|
|
if (!entry) {
|
|
|
|
kernfs_put(target);
|
|
|
|
return -ENOENT;
|
|
|
|
}
|
|
|
|
|
2019-12-11 09:09:06 -07:00
|
|
|
if (!symlink_name)
|
|
|
|
symlink_name = target_name;
|
|
|
|
|
|
|
|
link = kernfs_create_link(kobj->sd, symlink_name, entry);
|
2020-02-03 18:37:45 -07:00
|
|
|
if (PTR_ERR(link) == -EEXIST)
|
2019-12-11 09:09:06 -07:00
|
|
|
sysfs_warn_dup(kobj->sd, symlink_name);
|
2015-04-22 09:36:06 -07:00
|
|
|
|
|
|
|
kernfs_put(entry);
|
|
|
|
kernfs_put(target);
|
2017-11-27 16:10:32 -07:00
|
|
|
return PTR_ERR_OR_ZERO(link);
|
2015-04-22 09:36:06 -07:00
|
|
|
}
|
2019-12-11 09:09:06 -07:00
|
|
|
EXPORT_SYMBOL_GPL(compat_only_sysfs_link_entry_to_kobj);
|
2020-02-26 20:37:13 -07:00
|
|
|
|
|
|
|
static int sysfs_group_attrs_change_owner(struct kernfs_node *grp_kn,
|
|
|
|
const struct attribute_group *grp,
|
|
|
|
struct iattr *newattrs)
|
|
|
|
{
|
|
|
|
struct kernfs_node *kn;
|
|
|
|
int error;
|
|
|
|
|
|
|
|
if (grp->attrs) {
|
|
|
|
struct attribute *const *attr;
|
|
|
|
|
|
|
|
for (attr = grp->attrs; *attr; attr++) {
|
|
|
|
kn = kernfs_find_and_get(grp_kn, (*attr)->name);
|
|
|
|
if (!kn)
|
|
|
|
return -ENOENT;
|
|
|
|
|
|
|
|
error = kernfs_setattr(kn, newattrs);
|
|
|
|
kernfs_put(kn);
|
|
|
|
if (error)
|
|
|
|
return error;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
if (grp->bin_attrs) {
|
|
|
|
struct bin_attribute *const *bin_attr;
|
|
|
|
|
|
|
|
for (bin_attr = grp->bin_attrs; *bin_attr; bin_attr++) {
|
|
|
|
kn = kernfs_find_and_get(grp_kn, (*bin_attr)->attr.name);
|
|
|
|
if (!kn)
|
|
|
|
return -ENOENT;
|
|
|
|
|
|
|
|
error = kernfs_setattr(kn, newattrs);
|
|
|
|
kernfs_put(kn);
|
|
|
|
if (error)
|
|
|
|
return error;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
/**
|
|
|
|
* sysfs_group_change_owner - change owner of an attribute group.
|
|
|
|
* @kobj: The kobject containing the group.
|
|
|
|
* @grp: The attribute group.
|
|
|
|
* @kuid: new owner's kuid
|
|
|
|
* @kgid: new owner's kgid
|
|
|
|
*
|
|
|
|
* Returns 0 on success or error code on failure.
|
|
|
|
*/
|
|
|
|
int sysfs_group_change_owner(struct kobject *kobj,
|
|
|
|
const struct attribute_group *grp, kuid_t kuid,
|
|
|
|
kgid_t kgid)
|
|
|
|
{
|
|
|
|
struct kernfs_node *grp_kn;
|
|
|
|
int error;
|
|
|
|
struct iattr newattrs = {
|
|
|
|
.ia_valid = ATTR_UID | ATTR_GID,
|
|
|
|
.ia_uid = kuid,
|
|
|
|
.ia_gid = kgid,
|
|
|
|
};
|
|
|
|
|
|
|
|
if (!kobj->state_in_sysfs)
|
|
|
|
return -EINVAL;
|
|
|
|
|
|
|
|
if (grp->name) {
|
|
|
|
grp_kn = kernfs_find_and_get(kobj->sd, grp->name);
|
|
|
|
} else {
|
|
|
|
kernfs_get(kobj->sd);
|
|
|
|
grp_kn = kobj->sd;
|
|
|
|
}
|
|
|
|
if (!grp_kn)
|
|
|
|
return -ENOENT;
|
|
|
|
|
|
|
|
error = kernfs_setattr(grp_kn, &newattrs);
|
|
|
|
if (!error)
|
|
|
|
error = sysfs_group_attrs_change_owner(grp_kn, grp, &newattrs);
|
|
|
|
|
|
|
|
kernfs_put(grp_kn);
|
|
|
|
|
|
|
|
return error;
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(sysfs_group_change_owner);
|
|
|
|
|
|
|
|
/**
|
|
|
|
* sysfs_groups_change_owner - change owner of a set of attribute groups.
|
|
|
|
* @kobj: The kobject containing the groups.
|
|
|
|
* @groups: The attribute groups.
|
|
|
|
* @kuid: new owner's kuid
|
|
|
|
* @kgid: new owner's kgid
|
|
|
|
*
|
|
|
|
* Returns 0 on success or error code on failure.
|
|
|
|
*/
|
|
|
|
int sysfs_groups_change_owner(struct kobject *kobj,
|
|
|
|
const struct attribute_group **groups,
|
|
|
|
kuid_t kuid, kgid_t kgid)
|
|
|
|
{
|
|
|
|
int error = 0, i;
|
|
|
|
|
|
|
|
if (!kobj->state_in_sysfs)
|
|
|
|
return -EINVAL;
|
|
|
|
|
|
|
|
if (!groups)
|
|
|
|
return 0;
|
|
|
|
|
|
|
|
for (i = 0; groups[i]; i++) {
|
|
|
|
error = sysfs_group_change_owner(kobj, groups[i], kuid, kgid);
|
|
|
|
if (error)
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
|
|
|
|
return error;
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(sysfs_groups_change_owner);
|