fs/jfs/ioctl.c

Source file repositories/reference/linux-study-clean/fs/jfs/ioctl.c

File Facts

System
Linux kernel
Corpus path
fs/jfs/ioctl.c
Extension
.c
Size
3094 bytes
Lines
146
Domain
Core OS
Bucket
VFS And Filesystem Core
Inferred role
Core OS: implementation source
Status
source implementation candidate

Why This File Exists

Core operating-system implementation surface: boot, tasks, memory, VFS, syscall-facing interfaces, synchronization, credentials, and isolation.

Dependency Surface

Detected Declarations

Annotated Snippet

if (from) {
			if (jfs_map[index].ext2_flag & flags)
				mapped |= jfs_map[index].jfs_flag;
		} else {
			if (jfs_map[index].jfs_flag & flags)
				mapped |= jfs_map[index].ext2_flag;
		}
		index++;
	}
	return mapped;
}

int jfs_fileattr_get(struct dentry *dentry, struct file_kattr *fa)
{
	struct jfs_inode_info *jfs_inode = JFS_IP(d_inode(dentry));
	unsigned int flags = jfs_inode->mode2 & JFS_FL_USER_VISIBLE;

	if (d_is_special(dentry))
		return -ENOTTY;

	fileattr_fill_flags(fa, jfs_map_ext2(flags, 0));

	return 0;
}

int jfs_fileattr_set(struct mnt_idmap *idmap,
		     struct dentry *dentry, struct file_kattr *fa)
{
	struct inode *inode = d_inode(dentry);
	struct jfs_inode_info *jfs_inode = JFS_IP(inode);
	unsigned int flags;

	if (d_is_special(dentry))
		return -ENOTTY;

	if (fileattr_has_fsx(fa))
		return -EOPNOTSUPP;

	flags = jfs_map_ext2(fa->flags, 1);
	if (!S_ISDIR(inode->i_mode))
		flags &= ~JFS_DIRSYNC_FL;

	/* Is it quota file? Do not allow user to mess with it */
	if (IS_NOQUOTA(inode))
		return -EPERM;

	flags = flags & JFS_FL_USER_MODIFIABLE;
	flags |= jfs_inode->mode2 & ~JFS_FL_USER_MODIFIABLE;
	jfs_inode->mode2 = flags;

	jfs_set_inode_flags(inode);
	inode_set_ctime_current(inode);
	mark_inode_dirty(inode);

	return 0;
}

long jfs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
{
	struct inode *inode = file_inode(filp);

	switch (cmd) {
	case FITRIM:
	{
		struct super_block *sb = inode->i_sb;
		struct fstrim_range range;
		s64 ret = 0;

		if (!capable(CAP_SYS_ADMIN))
			return -EPERM;

		if (!bdev_max_discard_sectors(sb->s_bdev)) {
			jfs_warn("FITRIM not supported on device");
			return -EOPNOTSUPP;
		}

		if (copy_from_user(&range, (struct fstrim_range __user *)arg,
		    sizeof(range)))
			return -EFAULT;

		range.minlen = max_t(unsigned int, range.minlen,
				     bdev_discard_granularity(sb->s_bdev));

		ret = jfs_ioc_trim(inode, &range);
		if (ret < 0)
			return ret;

		if (copy_to_user((struct fstrim_range __user *)arg, &range,
		    sizeof(range)))
			return -EFAULT;

Annotation

Implementation Notes