#include <linux/pagemap.h>
#include <linux/namei.h>
#include <linux/backing-dev.h>
+#include <linux/capability.h>
#include "sysfs.h"
extern struct super_block * sysfs_sb;
.capabilities = BDI_CAP_NO_ACCT_DIRTY | BDI_CAP_NO_WRITEBACK,
};
-struct inode * sysfs_new_inode(mode_t mode)
+static struct inode_operations sysfs_inode_operations ={
+ .setattr = sysfs_setattr,
+};
+
+int sysfs_setattr(struct dentry * dentry, struct iattr * iattr)
+{
+ struct inode * inode = dentry->d_inode;
+ struct sysfs_dirent * sd = dentry->d_fsdata;
+ struct iattr * sd_iattr;
+ unsigned int ia_valid = iattr->ia_valid;
+ int error;
+
+ if (!sd)
+ return -EINVAL;
+
+ sd_iattr = sd->s_iattr;
+
+ error = inode_change_ok(inode, iattr);
+ if (error)
+ return error;
+
+ error = inode_setattr(inode, iattr);
+ if (error)
+ return error;
+
+ if (!sd_iattr) {
+ /* setting attributes for the first time, allocate now */
+ sd_iattr = kzalloc(sizeof(struct iattr), GFP_KERNEL);
+ if (!sd_iattr)
+ return -ENOMEM;
+ /* assign default attributes */
+ sd_iattr->ia_mode = sd->s_mode;
+ sd_iattr->ia_uid = 0;
+ sd_iattr->ia_gid = 0;
+ sd_iattr->ia_atime = sd_iattr->ia_mtime = sd_iattr->ia_ctime = CURRENT_TIME;
+ sd->s_iattr = sd_iattr;
+ }
+
+ /* attributes were changed atleast once in past */
+
+ if (ia_valid & ATTR_UID)
+ sd_iattr->ia_uid = iattr->ia_uid;
+ if (ia_valid & ATTR_GID)
+ sd_iattr->ia_gid = iattr->ia_gid;
+ if (ia_valid & ATTR_ATIME)
+ sd_iattr->ia_atime = timespec_trunc(iattr->ia_atime,
+ inode->i_sb->s_time_gran);
+ if (ia_valid & ATTR_MTIME)
+ sd_iattr->ia_mtime = timespec_trunc(iattr->ia_mtime,
+ inode->i_sb->s_time_gran);
+ if (ia_valid & ATTR_CTIME)
+ sd_iattr->ia_ctime = timespec_trunc(iattr->ia_ctime,
+ inode->i_sb->s_time_gran);
+ if (ia_valid & ATTR_MODE) {
+ umode_t mode = iattr->ia_mode;
+
+ if (!in_group_p(inode->i_gid) && !capable(CAP_FSETID))
+ mode &= ~S_ISGID;
+ sd_iattr->ia_mode = sd->s_mode = mode;
+ }
+
+ return error;
+}
+
+static inline void set_default_inode_attr(struct inode * inode, mode_t mode)
+{
+ inode->i_mode = mode;
+ inode->i_uid = 0;
+ inode->i_gid = 0;
+ inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
+}
+
+static inline void set_inode_attr(struct inode * inode, struct iattr * iattr)
+{
+ inode->i_mode = iattr->ia_mode;
+ inode->i_uid = iattr->ia_uid;
+ inode->i_gid = iattr->ia_gid;
+ inode->i_atime = iattr->ia_atime;
+ inode->i_mtime = iattr->ia_mtime;
+ inode->i_ctime = iattr->ia_ctime;
+}
+
+struct inode * sysfs_new_inode(mode_t mode, struct sysfs_dirent * sd)
{
struct inode * inode = new_inode(sysfs_sb);
if (inode) {
- inode->i_mode = mode;
- inode->i_uid = 0;
- inode->i_gid = 0;
inode->i_blksize = PAGE_CACHE_SIZE;
inode->i_blocks = 0;
- inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
inode->i_mapping->a_ops = &sysfs_aops;
inode->i_mapping->backing_dev_info = &sysfs_backing_dev_info;
+ inode->i_op = &sysfs_inode_operations;
+
+ if (sd->s_iattr) {
+ /* sysfs_dirent has non-default attributes
+ * get them for the new inode from persistent copy
+ * in sysfs_dirent
+ */
+ set_inode_attr(inode, sd->s_iattr);
+ } else
+ set_default_inode_attr(inode, mode);
}
return inode;
}
struct inode * inode = NULL;
if (dentry) {
if (!dentry->d_inode) {
- if ((inode = sysfs_new_inode(mode))) {
+ struct sysfs_dirent * sd = dentry->d_fsdata;
+ if ((inode = sysfs_new_inode(mode, sd))) {
if (dentry->d_parent && dentry->d_parent->d_inode) {
struct inode *p_inode = dentry->d_parent->d_inode;
p_inode->i_mtime = p_inode->i_ctime = CURRENT_TIME;
return error;
}
-struct dentry * sysfs_get_dentry(struct dentry * parent, const char * name)
-{
- struct qstr qstr;
-
- qstr.name = name;
- qstr.len = strlen(name);
- qstr.hash = full_name_hash(name,qstr.len);
- return lookup_hash(&qstr,parent);
-}
-
/*
* Get the name for corresponding element represented by the given sysfs_dirent
*/
struct bin_attribute * bin_attr;
struct sysfs_symlink * sl;
- if (!sd || !sd->s_element)
- BUG();
+ BUG_ON(!sd || !sd->s_element);
switch (sd->s_type) {
case SYSFS_DIR:
/*
* Unhashes the dentry corresponding to given sysfs_dirent
- * Called with parent inode's i_sem held.
+ * Called with parent inode's i_mutex held.
*/
void sysfs_drop_dentry(struct sysfs_dirent * sd, struct dentry * parent)
{
void sysfs_hash_and_remove(struct dentry * dir, const char * name)
{
struct sysfs_dirent * sd;
- struct sysfs_dirent * parent_sd = dir->d_fsdata;
+ struct sysfs_dirent * parent_sd;
+
+ if (!dir)
+ return;
- down(&dir->d_inode->i_sem);
+ if (dir->d_inode == NULL)
+ /* no inode means this hasn't been made visible yet */
+ return;
+
+ parent_sd = dir->d_fsdata;
+ mutex_lock(&dir->d_inode->i_mutex);
list_for_each_entry(sd, &parent_sd->s_children, s_sibling) {
if (!sd->s_element)
continue;
break;
}
}
- up(&dir->d_inode->i_sem);
+ mutex_unlock(&dir->d_inode->i_mutex);
}
-
-
git://git.onelab.eu / linux-2.6.git / blobdiff