| .. | .. |
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| 6 | 6 | * Copyright (c) 2007 SUSE Linux Products GmbH |
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| 7 | 7 | * Copyright (c) 2007 Tejun Heo <teheo@suse.de> |
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| 8 | 8 | * |
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| 9 | | - * Please see Documentation/filesystems/sysfs.txt for more information. |
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| 9 | + * Please see Documentation/filesystems/sysfs.rst for more information. |
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| 10 | 10 | */ |
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| 11 | 11 | |
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| 12 | 12 | #include <linux/module.h> |
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| .. | .. |
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| 15 | 15 | #include <linux/list.h> |
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| 16 | 16 | #include <linux/mutex.h> |
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| 17 | 17 | #include <linux/seq_file.h> |
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| 18 | | -#ifndef __GENKSYMS__ |
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| 19 | 18 | #include <linux/mm.h> |
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| 20 | | -#endif |
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| 21 | 19 | |
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| 22 | 20 | #include "sysfs.h" |
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| 23 | | -#include "../kernfs/kernfs-internal.h" |
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| 24 | 21 | |
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| 25 | 22 | /* |
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| 26 | 23 | * Determine ktype->sysfs_ops for the given kernfs_node. This function |
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| .. | .. |
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| 328 | 325 | kuid_t uid; |
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| 329 | 326 | kgid_t gid; |
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| 330 | 327 | |
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| 331 | | - BUG_ON(!kobj || !kobj->sd || !attr); |
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| 328 | + if (WARN_ON(!kobj || !kobj->sd || !attr)) |
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| 329 | + return -EINVAL; |
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| 332 | 330 | |
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| 333 | 331 | kobject_get_ownership(kobj, &uid, &gid); |
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| 334 | 332 | return sysfs_add_file_mode_ns(kobj->sd, attr, false, attr->mode, |
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| .. | .. |
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| 337 | 335 | } |
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| 338 | 336 | EXPORT_SYMBOL_GPL(sysfs_create_file_ns); |
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| 339 | 337 | |
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| 340 | | -int sysfs_create_files(struct kobject *kobj, const struct attribute **ptr) |
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| 338 | +int sysfs_create_files(struct kobject *kobj, const struct attribute * const *ptr) |
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| 341 | 339 | { |
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| 342 | 340 | int err = 0; |
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| 343 | 341 | int i; |
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| .. | .. |
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| 495 | 493 | kernfs_put(kn); |
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| 496 | 494 | return ret; |
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| 497 | 495 | } |
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| 496 | +EXPORT_SYMBOL_GPL(sysfs_remove_file_self); |
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| 498 | 497 | |
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| 499 | | -void sysfs_remove_files(struct kobject *kobj, const struct attribute **ptr) |
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| 498 | +void sysfs_remove_files(struct kobject *kobj, const struct attribute * const *ptr) |
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| 500 | 499 | { |
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| 501 | 500 | int i; |
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| 501 | + |
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| 502 | 502 | for (i = 0; ptr[i]; i++) |
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| 503 | 503 | sysfs_remove_file(kobj, ptr[i]); |
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| 504 | 504 | } |
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| .. | .. |
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| 540 | 540 | kuid_t uid; |
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| 541 | 541 | kgid_t gid; |
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| 542 | 542 | |
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| 543 | | - BUG_ON(!kobj || !kobj->sd || !attr); |
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| 543 | + if (WARN_ON(!kobj || !kobj->sd || !attr)) |
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| 544 | + return -EINVAL; |
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| 544 | 545 | |
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| 545 | 546 | kobject_get_ownership(kobj, &uid, &gid); |
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| 546 | 547 | return sysfs_add_file_mode_ns(kobj->sd, &attr->attr, true, |
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| .. | .. |
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| 560 | 561 | } |
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| 561 | 562 | EXPORT_SYMBOL_GPL(sysfs_remove_bin_file); |
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| 562 | 563 | |
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| 564 | +static int internal_change_owner(struct kernfs_node *kn, kuid_t kuid, |
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| 565 | + kgid_t kgid) |
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| 566 | +{ |
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| 567 | + struct iattr newattrs = { |
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| 568 | + .ia_valid = ATTR_UID | ATTR_GID, |
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| 569 | + .ia_uid = kuid, |
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| 570 | + .ia_gid = kgid, |
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| 571 | + }; |
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| 572 | + return kernfs_setattr(kn, &newattrs); |
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| 573 | +} |
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| 574 | + |
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| 575 | +/** |
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| 576 | + * sysfs_link_change_owner - change owner of a sysfs file. |
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| 577 | + * @kobj: object of the kernfs_node the symlink is located in. |
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| 578 | + * @targ: object of the kernfs_node the symlink points to. |
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| 579 | + * @name: name of the link. |
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| 580 | + * @kuid: new owner's kuid |
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| 581 | + * @kgid: new owner's kgid |
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| 582 | + * |
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| 583 | + * This function looks up the sysfs symlink entry @name under @kobj and changes |
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| 584 | + * the ownership to @kuid/@kgid. The symlink is looked up in the namespace of |
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| 585 | + * @targ. |
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| 586 | + * |
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| 587 | + * Returns 0 on success or error code on failure. |
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| 588 | + */ |
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| 589 | +int sysfs_link_change_owner(struct kobject *kobj, struct kobject *targ, |
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| 590 | + const char *name, kuid_t kuid, kgid_t kgid) |
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| 591 | +{ |
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| 592 | + struct kernfs_node *kn = NULL; |
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| 593 | + int error; |
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| 594 | + |
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| 595 | + if (!name || !kobj->state_in_sysfs || !targ->state_in_sysfs) |
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| 596 | + return -EINVAL; |
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| 597 | + |
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| 598 | + error = -ENOENT; |
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| 599 | + kn = kernfs_find_and_get_ns(kobj->sd, name, targ->sd->ns); |
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| 600 | + if (!kn) |
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| 601 | + goto out; |
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| 602 | + |
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| 603 | + error = -EINVAL; |
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| 604 | + if (kernfs_type(kn) != KERNFS_LINK) |
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| 605 | + goto out; |
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| 606 | + if (kn->symlink.target_kn->priv != targ) |
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| 607 | + goto out; |
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| 608 | + |
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| 609 | + error = internal_change_owner(kn, kuid, kgid); |
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| 610 | + |
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| 611 | +out: |
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| 612 | + kernfs_put(kn); |
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| 613 | + return error; |
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| 614 | +} |
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| 615 | + |
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| 616 | +/** |
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| 617 | + * sysfs_file_change_owner - change owner of a sysfs file. |
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| 618 | + * @kobj: object. |
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| 619 | + * @name: name of the file to change. |
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| 620 | + * @kuid: new owner's kuid |
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| 621 | + * @kgid: new owner's kgid |
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| 622 | + * |
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| 623 | + * This function looks up the sysfs entry @name under @kobj and changes the |
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| 624 | + * ownership to @kuid/@kgid. |
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| 625 | + * |
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| 626 | + * Returns 0 on success or error code on failure. |
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| 627 | + */ |
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| 628 | +int sysfs_file_change_owner(struct kobject *kobj, const char *name, kuid_t kuid, |
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| 629 | + kgid_t kgid) |
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| 630 | +{ |
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| 631 | + struct kernfs_node *kn; |
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| 632 | + int error; |
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| 633 | + |
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| 634 | + if (!name) |
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| 635 | + return -EINVAL; |
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| 636 | + |
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| 637 | + if (!kobj->state_in_sysfs) |
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| 638 | + return -EINVAL; |
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| 639 | + |
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| 640 | + kn = kernfs_find_and_get(kobj->sd, name); |
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| 641 | + if (!kn) |
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| 642 | + return -ENOENT; |
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| 643 | + |
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| 644 | + error = internal_change_owner(kn, kuid, kgid); |
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| 645 | + |
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| 646 | + kernfs_put(kn); |
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| 647 | + |
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| 648 | + return error; |
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| 649 | +} |
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| 650 | +EXPORT_SYMBOL_GPL(sysfs_file_change_owner); |
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| 651 | + |
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| 652 | +/** |
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| 653 | + * sysfs_change_owner - change owner of the given object. |
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| 654 | + * @kobj: object. |
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| 655 | + * @kuid: new owner's kuid |
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| 656 | + * @kgid: new owner's kgid |
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| 657 | + * |
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| 658 | + * Change the owner of the default directory, files, groups, and attributes of |
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| 659 | + * @kobj to @kuid/@kgid. Note that sysfs_change_owner mirrors how the sysfs |
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| 660 | + * entries for a kobject are added by driver core. In summary, |
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| 661 | + * sysfs_change_owner() takes care of the default directory entry for @kobj, |
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| 662 | + * the default attributes associated with the ktype of @kobj and the default |
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| 663 | + * attributes associated with the ktype of @kobj. |
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| 664 | + * Additional properties not added by driver core have to be changed by the |
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| 665 | + * driver or subsystem which created them. This is similar to how |
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| 666 | + * driver/subsystem specific entries are removed. |
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| 667 | + * |
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| 668 | + * Returns 0 on success or error code on failure. |
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| 669 | + */ |
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| 670 | +int sysfs_change_owner(struct kobject *kobj, kuid_t kuid, kgid_t kgid) |
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| 671 | +{ |
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| 672 | + int error; |
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| 673 | + const struct kobj_type *ktype; |
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| 674 | + |
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| 675 | + if (!kobj->state_in_sysfs) |
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| 676 | + return -EINVAL; |
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| 677 | + |
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| 678 | + /* Change the owner of the kobject itself. */ |
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| 679 | + error = internal_change_owner(kobj->sd, kuid, kgid); |
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| 680 | + if (error) |
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| 681 | + return error; |
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| 682 | + |
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| 683 | + ktype = get_ktype(kobj); |
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| 684 | + if (ktype) { |
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| 685 | + struct attribute **kattr; |
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| 686 | + |
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| 687 | + /* |
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| 688 | + * Change owner of the default attributes associated with the |
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| 689 | + * ktype of @kobj. |
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| 690 | + */ |
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| 691 | + for (kattr = ktype->default_attrs; kattr && *kattr; kattr++) { |
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| 692 | + error = sysfs_file_change_owner(kobj, (*kattr)->name, |
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| 693 | + kuid, kgid); |
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| 694 | + if (error) |
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| 695 | + return error; |
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| 696 | + } |
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| 697 | + |
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| 698 | + /* |
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| 699 | + * Change owner of the default groups associated with the |
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| 700 | + * ktype of @kobj. |
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| 701 | + */ |
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| 702 | + error = sysfs_groups_change_owner(kobj, ktype->default_groups, |
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| 703 | + kuid, kgid); |
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| 704 | + if (error) |
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| 705 | + return error; |
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| 706 | + } |
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| 707 | + |
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| 708 | + return 0; |
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| 709 | +} |
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| 710 | +EXPORT_SYMBOL_GPL(sysfs_change_owner); |
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| 711 | + |
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| 563 | 712 | /** |
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| 564 | 713 | * sysfs_emit - scnprintf equivalent, aware of PAGE_SIZE buffer. |
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| 565 | 714 | * @buf: start of PAGE_SIZE buffer. |
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