diff options
| -rw-r--r-- | fs/sysfs/dir.c | 82 |
1 files changed, 60 insertions, 22 deletions
diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c index 699f371b9f12..5c4703d751b5 100644 --- a/fs/sysfs/dir.c +++ b/fs/sysfs/dir.c @@ -837,11 +837,46 @@ static inline unsigned char dt_type(struct sysfs_dirent *sd) return (sd->s_mode >> 12) & 15; } +static int sysfs_dir_release(struct inode *inode, struct file *filp) +{ + sysfs_put(filp->private_data); + return 0; +} + +static struct sysfs_dirent *sysfs_dir_pos(struct sysfs_dirent *parent_sd, + ino_t ino, struct sysfs_dirent *pos) +{ + if (pos) { + int valid = !(pos->s_flags & SYSFS_FLAG_REMOVED) && + pos->s_parent == parent_sd && + ino == pos->s_ino; + sysfs_put(pos); + if (valid) + return pos; + } + pos = NULL; + if ((ino > 1) && (ino < INT_MAX)) { + pos = parent_sd->s_dir.children; + while (pos && (ino > pos->s_ino)) + pos = pos->s_sibling; + } + return pos; +} + +static struct sysfs_dirent *sysfs_dir_next_pos(struct sysfs_dirent *parent_sd, + ino_t ino, struct sysfs_dirent *pos) +{ + pos = sysfs_dir_pos(parent_sd, ino, pos); + if (pos) + pos = pos->s_sibling; + return pos; +} + static int sysfs_readdir(struct file * filp, void * dirent, filldir_t filldir) { struct dentry *dentry = filp->f_path.dentry; struct sysfs_dirent * parent_sd = dentry->d_fsdata; - struct sysfs_dirent *pos; + struct sysfs_dirent *pos = filp->private_data; ino_t ino; if (filp->f_pos == 0) { @@ -857,29 +892,31 @@ static int sysfs_readdir(struct file * filp, void * dirent, filldir_t filldir) if (filldir(dirent, "..", 2, filp->f_pos, ino, DT_DIR) == 0) filp->f_pos++; } - if ((filp->f_pos > 1) && (filp->f_pos < INT_MAX)) { - mutex_lock(&sysfs_mutex); - - /* Skip the dentries we have already reported */ - pos = parent_sd->s_dir.children; - while (pos && (filp->f_pos > pos->s_ino)) - pos = pos->s_sibling; - - for ( ; pos; pos = pos->s_sibling) { - const char * name; - int len; - - name = pos->s_name; - len = strlen(name); - filp->f_pos = ino = pos->s_ino; + mutex_lock(&sysfs_mutex); + for (pos = sysfs_dir_pos(parent_sd, filp->f_pos, pos); + pos; + pos = sysfs_dir_next_pos(parent_sd, filp->f_pos, pos)) { + const char * name; + unsigned int type; + int len, ret; + + name = pos->s_name; + len = strlen(name); + ino = pos->s_ino; + type = dt_type(pos); + filp->f_pos = ino; + filp->private_data = sysfs_get(pos); - if (filldir(dirent, name, len, filp->f_pos, ino, - dt_type(pos)) < 0) - break; - } - if (!pos) - filp->f_pos = INT_MAX; mutex_unlock(&sysfs_mutex); + ret = filldir(dirent, name, len, filp->f_pos, ino, type); + mutex_lock(&sysfs_mutex); + if (ret < 0) + break; + } + mutex_unlock(&sysfs_mutex); + if ((filp->f_pos > 1) && !pos) { /* EOF */ + filp->f_pos = INT_MAX; + filp->private_data = NULL; } return 0; } @@ -888,5 +925,6 @@ static int sysfs_readdir(struct file * filp, void * dirent, filldir_t filldir) const struct file_operations sysfs_dir_operations = { .read = generic_read_dir, .readdir = sysfs_readdir, + .release = sysfs_dir_release, .llseek = generic_file_llseek, }; |