From 49fe604781cbb03eb6ff12a7bc4ad8eef8b830c4 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Tue, 1 Oct 2013 17:42:08 -0400 Subject: [PATCH] sysfs: prepare open path for unified regular / bin file handling sysfs bin file handling will be merged into the regular file support. This patch prepares the open path. This patch updates sysfs_open_file() such that it can handle both regular and bin files. This is a preparation and the new bin file path isn't used yet. Signed-off-by: Tejun Heo Signed-off-by: Greg Kroah-Hartman --- fs/sysfs/file.c | 58 ++++++++++++++++++++++++++++--------------------- 1 file changed, 33 insertions(+), 25 deletions(-) diff --git a/fs/sysfs/file.c b/fs/sysfs/file.c index 02797a134cf8..417d005955d9 100644 --- a/fs/sysfs/file.c +++ b/fs/sysfs/file.c @@ -610,38 +610,40 @@ static int sysfs_open_file(struct inode *inode, struct file *file) struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata; struct kobject *kobj = attr_sd->s_parent->s_dir.kobj; struct sysfs_open_file *of; - const struct sysfs_ops *ops; + bool has_read, has_write; int error = -EACCES; /* need attr_sd for attr and ops, its parent for kobj */ if (!sysfs_get_active(attr_sd)) return -ENODEV; - /* every kobject with an attribute needs a ktype assigned */ - ops = sysfs_file_ops(attr_sd); - if (WARN(!ops, KERN_ERR - "missing sysfs attribute operations for kobject: %s\n", - kobject_name(kobj))) - goto err_out; + if (sysfs_is_bin(attr_sd)) { + struct bin_attribute *battr = attr_sd->s_bin_attr.bin_attr; - /* File needs write support. - * The inode's perms must say it's ok, - * and we must have a store method. - */ - if (file->f_mode & FMODE_WRITE) { - if (!(inode->i_mode & S_IWUGO) || !ops->store) - goto err_out; - } + has_read = battr->read || battr->mmap; + has_write = battr->write || battr->mmap; + } else { + const struct sysfs_ops *ops = sysfs_file_ops(attr_sd); - /* File needs read support. - * The inode's perms must say it's ok, and we there - * must be a show method for it. - */ - if (file->f_mode & FMODE_READ) { - if (!(inode->i_mode & S_IRUGO) || !ops->show) + /* every kobject with an attribute needs a ktype assigned */ + if (WARN(!ops, KERN_ERR + "missing sysfs attribute operations for kobject: %s\n", + kobject_name(kobj))) goto err_out; + + has_read = ops->show; + has_write = ops->store; } + /* check perms and supported operations */ + if ((file->f_mode & FMODE_WRITE) && + (!(inode->i_mode & S_IWUGO) || !has_write)) + goto err_out; + + if ((file->f_mode & FMODE_READ) && + (!(inode->i_mode & S_IRUGO) || !has_read)) + goto err_out; + /* allocate a sysfs_open_file for the file */ error = -ENOMEM; of = kzalloc(sizeof(struct sysfs_open_file), GFP_KERNEL); @@ -653,11 +655,14 @@ static int sysfs_open_file(struct inode *inode, struct file *file) of->file = file; /* - * Always instantiate seq_file even if read access is not - * implemented or requested. This unifies private data access and - * most files are readable anyway. + * Always instantiate seq_file even if read access doesn't use + * seq_file or is not requested. This unifies private data access + * and readable regular files are the vast majority anyway. */ - error = single_open(file, sysfs_seq_show, of); + if (sysfs_is_bin(attr_sd)) + error = single_open(file, NULL, of); + else + error = single_open(file, sysfs_seq_show, of); if (error) goto err_free; @@ -807,6 +812,9 @@ const struct file_operations sysfs_bin_operations = { .write = sysfs_write_file, .llseek = generic_file_llseek, .mmap = sysfs_bin_mmap, + .open = sysfs_open_file, + .release = sysfs_release, + .poll = sysfs_poll, }; int sysfs_add_file_mode_ns(struct sysfs_dirent *dir_sd, -- GitLab