From e61ab4ae48fbf477f5b9fcbec9e1b8dc789920d0 Mon Sep 17 00:00:00 2001 From: "Eric W. Biederman" Date: Fri, 20 Nov 2009 16:08:53 -0800 Subject: sysfs: Implement sysfs_getattr & sysfs_permission With the implementation of sysfs_getattr and sysfs_permission sysfs becomes able to lazily propogate inode attribute changes from the sysfs_dirents to the vfs inodes. This paves the way for deleting significant chunks of now unnecessary code. While doing this we did not reference sysfs_setattr from sysfs_symlink_inode_operations so I added along with sysfs_getattr and sysfs_permission. Acked-by: Tejun Heo Acked-by: Serge Hallyn Signed-off-by: Eric W. Biederman Signed-off-by: Greg Kroah-Hartman --- fs/sysfs/dir.c | 2 ++ fs/sysfs/inode.c | 64 +++++++++++++++++++++++++++++++++++++++--------------- fs/sysfs/symlink.c | 3 +++ fs/sysfs/sysfs.h | 2 ++ 4 files changed, 54 insertions(+), 17 deletions(-) (limited to 'fs/sysfs') diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c index 36ee6d817956..e319379d36db 100644 --- a/fs/sysfs/dir.c +++ b/fs/sysfs/dir.c @@ -800,7 +800,9 @@ static struct dentry * sysfs_lookup(struct inode *dir, struct dentry *dentry, const struct inode_operations sysfs_dir_inode_operations = { .lookup = sysfs_lookup, + .permission = sysfs_permission, .setattr = sysfs_setattr, + .getattr = sysfs_getattr, .setxattr = sysfs_setxattr, }; diff --git a/fs/sysfs/inode.c b/fs/sysfs/inode.c index 76e977c300f7..1ffd5559926f 100644 --- a/fs/sysfs/inode.c +++ b/fs/sysfs/inode.c @@ -37,7 +37,9 @@ static struct backing_dev_info sysfs_backing_dev_info = { }; static const struct inode_operations sysfs_inode_operations ={ + .permission = sysfs_permission, .setattr = sysfs_setattr, + .getattr = sysfs_getattr, .setxattr = sysfs_setxattr, }; @@ -196,7 +198,6 @@ static inline void set_default_inode_attr(struct inode * inode, mode_t mode) 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; @@ -227,38 +228,56 @@ static int sysfs_count_nlink(struct sysfs_dirent *sd) return nr + 2; } +static void sysfs_refresh_inode(struct sysfs_dirent *sd, struct inode *inode) +{ + struct sysfs_inode_attrs *iattrs = sd->s_iattr; + + inode->i_mode = sd->s_mode; + if (iattrs) { + /* sysfs_dirent has non-default attributes + * get them from persistent copy in sysfs_dirent + */ + set_inode_attr(inode, &iattrs->ia_iattr); + security_inode_notifysecctx(inode, + iattrs->ia_secdata, + iattrs->ia_secdata_len); + } + + if (sysfs_type(sd) == SYSFS_DIR) + inode->i_nlink = sysfs_count_nlink(sd); +} + +int sysfs_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat) +{ + struct sysfs_dirent *sd = dentry->d_fsdata; + struct inode *inode = dentry->d_inode; + + mutex_lock(&sysfs_mutex); + sysfs_refresh_inode(sd, inode); + mutex_unlock(&sysfs_mutex); + + generic_fillattr(inode, stat); + return 0; +} + static void sysfs_init_inode(struct sysfs_dirent *sd, struct inode *inode) { struct bin_attribute *bin_attr; - struct sysfs_inode_attrs *iattrs; inode->i_private = sysfs_get(sd); inode->i_mapping->a_ops = &sysfs_aops; inode->i_mapping->backing_dev_info = &sysfs_backing_dev_info; inode->i_op = &sysfs_inode_operations; - inode->i_ino = sd->s_ino; lockdep_set_class(&inode->i_mutex, &sysfs_inode_imutex_key); - iattrs = sd->s_iattr; - if (iattrs) { - /* sysfs_dirent has non-default attributes - * get them for the new inode from persistent copy - * in sysfs_dirent - */ - set_inode_attr(inode, &iattrs->ia_iattr); - if (iattrs->ia_secdata) - security_inode_notifysecctx(inode, - iattrs->ia_secdata, - iattrs->ia_secdata_len); - } else - set_default_inode_attr(inode, sd->s_mode); + set_default_inode_attr(inode, sd->s_mode); + sysfs_refresh_inode(sd, inode); /* initialize inode according to type */ switch (sysfs_type(sd)) { case SYSFS_DIR: inode->i_op = &sysfs_dir_inode_operations; inode->i_fop = &sysfs_dir_operations; - inode->i_nlink = sysfs_count_nlink(sd); break; case SYSFS_KOBJ_ATTR: inode->i_size = PAGE_SIZE; @@ -341,3 +360,14 @@ int sysfs_hash_and_remove(struct sysfs_dirent *dir_sd, const char *name) else return -ENOENT; } + +int sysfs_permission(struct inode *inode, int mask) +{ + struct sysfs_dirent *sd = inode->i_private; + + mutex_lock(&sysfs_mutex); + sysfs_refresh_inode(sd, inode); + mutex_unlock(&sysfs_mutex); + + return generic_permission(inode, mask, NULL); +} diff --git a/fs/sysfs/symlink.c b/fs/sysfs/symlink.c index 11374182ca67..c5eff49fa41b 100644 --- a/fs/sysfs/symlink.c +++ b/fs/sysfs/symlink.c @@ -214,6 +214,9 @@ const struct inode_operations sysfs_symlink_inode_operations = { .readlink = generic_readlink, .follow_link = sysfs_follow_link, .put_link = sysfs_put_link, + .setattr = sysfs_setattr, + .getattr = sysfs_getattr, + .permission = sysfs_permission, }; diff --git a/fs/sysfs/sysfs.h b/fs/sysfs/sysfs.h index a96d9678ae73..12ccc07459d8 100644 --- a/fs/sysfs/sysfs.h +++ b/fs/sysfs/sysfs.h @@ -156,7 +156,9 @@ static inline void __sysfs_put(struct sysfs_dirent *sd) struct inode *sysfs_get_inode(struct sysfs_dirent *sd); void sysfs_delete_inode(struct inode *inode); int sysfs_sd_setattr(struct sysfs_dirent *sd, struct iattr *iattr); +int sysfs_permission(struct inode *inode, int mask); int sysfs_setattr(struct dentry *dentry, struct iattr *iattr); +int sysfs_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat); int sysfs_setxattr(struct dentry *dentry, const char *name, const void *value, size_t size, int flags); int sysfs_hash_and_remove(struct sysfs_dirent *dir_sd, const char *name); -- cgit v1.2.3