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@@ -1,342 +0,0 @@
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-/*
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- * fs/sysfs/inode.c - basic sysfs inode and dentry operations
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- *
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- * Copyright (c) 2001-3 Patrick Mochel
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- * Copyright (c) 2007 SUSE Linux Products GmbH
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- * Copyright (c) 2007 Tejun Heo <teheo@suse.de>
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- *
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- * This file is released under the GPLv2.
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- *
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- * Please see Documentation/filesystems/sysfs.txt for more information.
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- */
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-
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-#undef DEBUG
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-
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-#include <linux/pagemap.h>
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-#include <linux/namei.h>
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-#include <linux/backing-dev.h>
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-#include <linux/capability.h>
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-#include <linux/errno.h>
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-#include <linux/sched.h>
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-#include <linux/slab.h>
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-#include <linux/sysfs.h>
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-#include <linux/xattr.h>
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-#include <linux/security.h>
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-#include "sysfs.h"
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-
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-static const struct address_space_operations sysfs_aops = {
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- .readpage = simple_readpage,
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- .write_begin = simple_write_begin,
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- .write_end = simple_write_end,
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-};
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-
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-static struct backing_dev_info sysfs_backing_dev_info = {
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- .name = "sysfs",
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- .ra_pages = 0, /* No readahead */
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- .capabilities = BDI_CAP_NO_ACCT_AND_WRITEBACK,
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-};
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-
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-static const struct inode_operations sysfs_inode_operations = {
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- .permission = sysfs_permission,
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- .setattr = sysfs_setattr,
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- .getattr = sysfs_getattr,
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- .setxattr = sysfs_setxattr,
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-};
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-
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-int __init sysfs_inode_init(void)
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-{
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- return bdi_init(&sysfs_backing_dev_info);
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-}
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-
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-static struct sysfs_inode_attrs *sysfs_init_inode_attrs(struct sysfs_dirent *sd)
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-{
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- struct sysfs_inode_attrs *attrs;
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- struct iattr *iattrs;
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-
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- attrs = kzalloc(sizeof(struct sysfs_inode_attrs), GFP_KERNEL);
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- if (!attrs)
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- return NULL;
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- iattrs = &attrs->ia_iattr;
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-
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- /* assign default attributes */
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- iattrs->ia_mode = sd->s_mode;
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- iattrs->ia_uid = GLOBAL_ROOT_UID;
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- iattrs->ia_gid = GLOBAL_ROOT_GID;
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- iattrs->ia_atime = iattrs->ia_mtime = iattrs->ia_ctime = CURRENT_TIME;
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-
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- return attrs;
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-}
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-
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-static int __kernfs_setattr(struct sysfs_dirent *sd, const struct iattr *iattr)
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-{
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- struct sysfs_inode_attrs *sd_attrs;
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- struct iattr *iattrs;
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- unsigned int ia_valid = iattr->ia_valid;
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-
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- sd_attrs = sd->s_iattr;
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-
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- if (!sd_attrs) {
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- /* setting attributes for the first time, allocate now */
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- sd_attrs = sysfs_init_inode_attrs(sd);
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- if (!sd_attrs)
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- return -ENOMEM;
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- sd->s_iattr = sd_attrs;
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- }
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- /* attributes were changed at least once in past */
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- iattrs = &sd_attrs->ia_iattr;
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-
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- if (ia_valid & ATTR_UID)
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- iattrs->ia_uid = iattr->ia_uid;
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- if (ia_valid & ATTR_GID)
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- iattrs->ia_gid = iattr->ia_gid;
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- if (ia_valid & ATTR_ATIME)
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- iattrs->ia_atime = iattr->ia_atime;
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- if (ia_valid & ATTR_MTIME)
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- iattrs->ia_mtime = iattr->ia_mtime;
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- if (ia_valid & ATTR_CTIME)
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- iattrs->ia_ctime = iattr->ia_ctime;
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- if (ia_valid & ATTR_MODE) {
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- umode_t mode = iattr->ia_mode;
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- iattrs->ia_mode = sd->s_mode = mode;
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- }
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- return 0;
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-}
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-
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-/**
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- * kernfs_setattr - set iattr on a node
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- * @sd: target node
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- * @iattr: iattr to set
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- *
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- * Returns 0 on success, -errno on failure.
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- */
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-int kernfs_setattr(struct sysfs_dirent *sd, const struct iattr *iattr)
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-{
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- int ret;
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-
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- mutex_lock(&sysfs_mutex);
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- ret = __kernfs_setattr(sd, iattr);
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- mutex_unlock(&sysfs_mutex);
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- return ret;
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-}
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-
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-int sysfs_setattr(struct dentry *dentry, struct iattr *iattr)
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-{
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- struct inode *inode = dentry->d_inode;
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- struct sysfs_dirent *sd = dentry->d_fsdata;
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- int error;
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-
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- if (!sd)
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- return -EINVAL;
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-
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- mutex_lock(&sysfs_mutex);
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- error = inode_change_ok(inode, iattr);
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- if (error)
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- goto out;
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-
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- error = __kernfs_setattr(sd, iattr);
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- if (error)
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- goto out;
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-
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- /* this ignores size changes */
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- setattr_copy(inode, iattr);
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-
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-out:
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- mutex_unlock(&sysfs_mutex);
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- return error;
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-}
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-
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-static int sysfs_sd_setsecdata(struct sysfs_dirent *sd, void **secdata,
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- u32 *secdata_len)
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-{
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- struct sysfs_inode_attrs *iattrs;
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- void *old_secdata;
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- size_t old_secdata_len;
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-
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- if (!sd->s_iattr) {
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- sd->s_iattr = sysfs_init_inode_attrs(sd);
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- if (!sd->s_iattr)
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- return -ENOMEM;
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- }
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-
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- iattrs = sd->s_iattr;
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- old_secdata = iattrs->ia_secdata;
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- old_secdata_len = iattrs->ia_secdata_len;
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-
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- iattrs->ia_secdata = *secdata;
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- iattrs->ia_secdata_len = *secdata_len;
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-
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- *secdata = old_secdata;
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- *secdata_len = old_secdata_len;
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- return 0;
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-}
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-
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-int sysfs_setxattr(struct dentry *dentry, const char *name, const void *value,
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- size_t size, int flags)
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-{
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- struct sysfs_dirent *sd = dentry->d_fsdata;
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- void *secdata;
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- int error;
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- u32 secdata_len = 0;
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-
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- if (!sd)
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- return -EINVAL;
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-
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- if (!strncmp(name, XATTR_SECURITY_PREFIX, XATTR_SECURITY_PREFIX_LEN)) {
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- const char *suffix = name + XATTR_SECURITY_PREFIX_LEN;
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- error = security_inode_setsecurity(dentry->d_inode, suffix,
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- value, size, flags);
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- if (error)
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- goto out;
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- error = security_inode_getsecctx(dentry->d_inode,
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- &secdata, &secdata_len);
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- if (error)
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- goto out;
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-
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- mutex_lock(&sysfs_mutex);
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- error = sysfs_sd_setsecdata(sd, &secdata, &secdata_len);
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- mutex_unlock(&sysfs_mutex);
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-
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- if (secdata)
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- security_release_secctx(secdata, secdata_len);
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- } else
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- return -EINVAL;
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-out:
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- return error;
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-}
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-
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-static inline void set_default_inode_attr(struct inode *inode, umode_t mode)
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-{
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- inode->i_mode = mode;
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- inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
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-}
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-
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-static inline void set_inode_attr(struct inode *inode, struct iattr *iattr)
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-{
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- inode->i_uid = iattr->ia_uid;
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- inode->i_gid = iattr->ia_gid;
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- inode->i_atime = iattr->ia_atime;
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- inode->i_mtime = iattr->ia_mtime;
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- inode->i_ctime = iattr->ia_ctime;
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-}
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-
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-static void sysfs_refresh_inode(struct sysfs_dirent *sd, struct inode *inode)
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-{
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- struct sysfs_inode_attrs *iattrs = sd->s_iattr;
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-
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- inode->i_mode = sd->s_mode;
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- if (iattrs) {
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- /* sysfs_dirent has non-default attributes
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- * get them from persistent copy in sysfs_dirent
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- */
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- set_inode_attr(inode, &iattrs->ia_iattr);
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- security_inode_notifysecctx(inode,
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- iattrs->ia_secdata,
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- iattrs->ia_secdata_len);
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- }
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-
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- if (sysfs_type(sd) == SYSFS_DIR)
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- set_nlink(inode, sd->s_dir.subdirs + 2);
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-}
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-
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-int sysfs_getattr(struct vfsmount *mnt, struct dentry *dentry,
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- struct kstat *stat)
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-{
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- struct sysfs_dirent *sd = dentry->d_fsdata;
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- struct inode *inode = dentry->d_inode;
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-
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- mutex_lock(&sysfs_mutex);
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- sysfs_refresh_inode(sd, inode);
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- mutex_unlock(&sysfs_mutex);
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-
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- generic_fillattr(inode, stat);
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- return 0;
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-}
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-
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-static void sysfs_init_inode(struct sysfs_dirent *sd, struct inode *inode)
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-{
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- kernfs_get(sd);
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- inode->i_private = sd;
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- inode->i_mapping->a_ops = &sysfs_aops;
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- inode->i_mapping->backing_dev_info = &sysfs_backing_dev_info;
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- inode->i_op = &sysfs_inode_operations;
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-
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- set_default_inode_attr(inode, sd->s_mode);
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- sysfs_refresh_inode(sd, inode);
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-
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- /* initialize inode according to type */
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- switch (sysfs_type(sd)) {
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- case SYSFS_DIR:
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- inode->i_op = &sysfs_dir_inode_operations;
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- inode->i_fop = &sysfs_dir_operations;
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- break;
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- case SYSFS_KOBJ_ATTR:
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- inode->i_size = sd->s_attr.size;
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- inode->i_fop = &kernfs_file_operations;
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- break;
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- case SYSFS_KOBJ_LINK:
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- inode->i_op = &sysfs_symlink_inode_operations;
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- break;
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- default:
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- BUG();
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- }
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-
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- unlock_new_inode(inode);
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-}
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-
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-/**
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- * sysfs_get_inode - get inode for sysfs_dirent
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- * @sb: super block
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- * @sd: sysfs_dirent to allocate inode for
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- *
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- * Get inode for @sd. If such inode doesn't exist, a new inode
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- * is allocated and basics are initialized. New inode is
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- * returned locked.
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- *
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- * LOCKING:
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- * Kernel thread context (may sleep).
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- *
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- * RETURNS:
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- * Pointer to allocated inode on success, NULL on failure.
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- */
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-struct inode *sysfs_get_inode(struct super_block *sb, struct sysfs_dirent *sd)
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-{
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- struct inode *inode;
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-
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- inode = iget_locked(sb, sd->s_ino);
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- if (inode && (inode->i_state & I_NEW))
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- sysfs_init_inode(sd, inode);
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-
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- return inode;
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-}
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-
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-/*
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- * The sysfs_dirent serves as both an inode and a directory entry for sysfs.
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- * To prevent the sysfs inode numbers from being freed prematurely we take a
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- * reference to sysfs_dirent from the sysfs inode. A
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- * super_operations.evict_inode() implementation is needed to drop that
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- * reference upon inode destruction.
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- */
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-void sysfs_evict_inode(struct inode *inode)
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-{
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- struct sysfs_dirent *sd = inode->i_private;
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-
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- truncate_inode_pages(&inode->i_data, 0);
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- clear_inode(inode);
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- kernfs_put(sd);
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-}
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-
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-int sysfs_permission(struct inode *inode, int mask)
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-{
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- struct sysfs_dirent *sd;
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-
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- if (mask & MAY_NOT_BLOCK)
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- return -ECHILD;
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-
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- sd = inode->i_private;
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-
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- mutex_lock(&sysfs_mutex);
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- sysfs_refresh_inode(sd, inode);
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- mutex_unlock(&sysfs_mutex);
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-
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- return generic_permission(inode, mask);
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-}
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