mirror of
				https://github.com/torvalds/linux.git
				synced 2025-11-04 10:40:15 +02:00 
			
		
		
		
	shmem: support idmapped mounts for tmpfs
This patch enables idmapped mounts for tmpfs when CONFIG_SHMEM is defined. Since all dedicated helpers for this functionality exist, in this patch we just pass down the idmap argument from the VFS methods to the relevant helpers. Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com> Tested-by: Christian Brauner (Microsoft) <brauner@kernel.org> Reviewed-by: Christian Brauner (Microsoft) <brauner@kernel.org> Reviewed-by: Seth Forshee (DigitalOcean) <sforshee@kernel.org> Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
This commit is contained in:
		
							parent
							
								
									3707d84c13
								
							
						
					
					
						commit
						7a80e5b8c6
					
				
					 1 changed files with 28 additions and 19 deletions
				
			
		
							
								
								
									
										47
									
								
								mm/shmem.c
									
									
									
									
									
								
							
							
						
						
									
										47
									
								
								mm/shmem.c
									
									
									
									
									
								
							| 
						 | 
				
			
			@ -1068,7 +1068,7 @@ static int shmem_getattr(struct mnt_idmap *idmap,
 | 
			
		|||
	stat->attributes_mask |= (STATX_ATTR_APPEND |
 | 
			
		||||
			STATX_ATTR_IMMUTABLE |
 | 
			
		||||
			STATX_ATTR_NODUMP);
 | 
			
		||||
	generic_fillattr(&nop_mnt_idmap, inode, stat);
 | 
			
		||||
	generic_fillattr(idmap, inode, stat);
 | 
			
		||||
 | 
			
		||||
	if (shmem_is_huge(NULL, inode, 0, false))
 | 
			
		||||
		stat->blksize = HPAGE_PMD_SIZE;
 | 
			
		||||
| 
						 | 
				
			
			@ -1091,7 +1091,7 @@ static int shmem_setattr(struct mnt_idmap *idmap,
 | 
			
		|||
	bool update_mtime = false;
 | 
			
		||||
	bool update_ctime = true;
 | 
			
		||||
 | 
			
		||||
	error = setattr_prepare(&nop_mnt_idmap, dentry, attr);
 | 
			
		||||
	error = setattr_prepare(idmap, dentry, attr);
 | 
			
		||||
	if (error)
 | 
			
		||||
		return error;
 | 
			
		||||
 | 
			
		||||
| 
						 | 
				
			
			@ -1129,9 +1129,9 @@ static int shmem_setattr(struct mnt_idmap *idmap,
 | 
			
		|||
		}
 | 
			
		||||
	}
 | 
			
		||||
 | 
			
		||||
	setattr_copy(&nop_mnt_idmap, inode, attr);
 | 
			
		||||
	setattr_copy(idmap, inode, attr);
 | 
			
		||||
	if (attr->ia_valid & ATTR_MODE)
 | 
			
		||||
		error = posix_acl_chmod(&nop_mnt_idmap, dentry, inode->i_mode);
 | 
			
		||||
		error = posix_acl_chmod(idmap, dentry, inode->i_mode);
 | 
			
		||||
	if (!error && update_ctime) {
 | 
			
		||||
		inode->i_ctime = current_time(inode);
 | 
			
		||||
		if (update_mtime)
 | 
			
		||||
| 
						 | 
				
			
			@ -2329,8 +2329,9 @@ static void shmem_set_inode_flags(struct inode *inode, unsigned int fsflags)
 | 
			
		|||
#define shmem_initxattrs NULL
 | 
			
		||||
#endif
 | 
			
		||||
 | 
			
		||||
static struct inode *shmem_get_inode(struct super_block *sb, struct inode *dir,
 | 
			
		||||
				     umode_t mode, dev_t dev, unsigned long flags)
 | 
			
		||||
static struct inode *shmem_get_inode(struct mnt_idmap *idmap, struct super_block *sb,
 | 
			
		||||
				     struct inode *dir, umode_t mode, dev_t dev,
 | 
			
		||||
				     unsigned long flags)
 | 
			
		||||
{
 | 
			
		||||
	struct inode *inode;
 | 
			
		||||
	struct shmem_inode_info *info;
 | 
			
		||||
| 
						 | 
				
			
			@ -2343,7 +2344,7 @@ static struct inode *shmem_get_inode(struct super_block *sb, struct inode *dir,
 | 
			
		|||
	inode = new_inode(sb);
 | 
			
		||||
	if (inode) {
 | 
			
		||||
		inode->i_ino = ino;
 | 
			
		||||
		inode_init_owner(&nop_mnt_idmap, inode, dir, mode);
 | 
			
		||||
		inode_init_owner(idmap, inode, dir, mode);
 | 
			
		||||
		inode->i_blocks = 0;
 | 
			
		||||
		inode->i_atime = inode->i_mtime = inode->i_ctime = current_time(inode);
 | 
			
		||||
		inode->i_generation = get_random_u32();
 | 
			
		||||
| 
						 | 
				
			
			@ -2921,7 +2922,7 @@ shmem_mknod(struct mnt_idmap *idmap, struct inode *dir,
 | 
			
		|||
	struct inode *inode;
 | 
			
		||||
	int error = -ENOSPC;
 | 
			
		||||
 | 
			
		||||
	inode = shmem_get_inode(dir->i_sb, dir, mode, dev, VM_NORESERVE);
 | 
			
		||||
	inode = shmem_get_inode(idmap, dir->i_sb, dir, mode, dev, VM_NORESERVE);
 | 
			
		||||
	if (inode) {
 | 
			
		||||
		error = simple_acl_create(dir, inode);
 | 
			
		||||
		if (error)
 | 
			
		||||
| 
						 | 
				
			
			@ -2952,7 +2953,7 @@ shmem_tmpfile(struct mnt_idmap *idmap, struct inode *dir,
 | 
			
		|||
	struct inode *inode;
 | 
			
		||||
	int error = -ENOSPC;
 | 
			
		||||
 | 
			
		||||
	inode = shmem_get_inode(dir->i_sb, dir, mode, 0, VM_NORESERVE);
 | 
			
		||||
	inode = shmem_get_inode(idmap, dir->i_sb, dir, mode, 0, VM_NORESERVE);
 | 
			
		||||
	if (inode) {
 | 
			
		||||
		error = security_inode_init_security(inode, dir,
 | 
			
		||||
						     NULL,
 | 
			
		||||
| 
						 | 
				
			
			@ -2975,8 +2976,8 @@ static int shmem_mkdir(struct mnt_idmap *idmap, struct inode *dir,
 | 
			
		|||
{
 | 
			
		||||
	int error;
 | 
			
		||||
 | 
			
		||||
	if ((error = shmem_mknod(&nop_mnt_idmap, dir, dentry,
 | 
			
		||||
				 mode | S_IFDIR, 0)))
 | 
			
		||||
	error = shmem_mknod(idmap, dir, dentry, mode | S_IFDIR, 0);
 | 
			
		||||
	if (error)
 | 
			
		||||
		return error;
 | 
			
		||||
	inc_nlink(dir);
 | 
			
		||||
	return 0;
 | 
			
		||||
| 
						 | 
				
			
			@ -2985,7 +2986,7 @@ static int shmem_mkdir(struct mnt_idmap *idmap, struct inode *dir,
 | 
			
		|||
static int shmem_create(struct mnt_idmap *idmap, struct inode *dir,
 | 
			
		||||
			struct dentry *dentry, umode_t mode, bool excl)
 | 
			
		||||
{
 | 
			
		||||
	return shmem_mknod(&nop_mnt_idmap, dir, dentry, mode | S_IFREG, 0);
 | 
			
		||||
	return shmem_mknod(idmap, dir, dentry, mode | S_IFREG, 0);
 | 
			
		||||
}
 | 
			
		||||
 | 
			
		||||
/*
 | 
			
		||||
| 
						 | 
				
			
			@ -3055,7 +3056,7 @@ static int shmem_whiteout(struct mnt_idmap *idmap,
 | 
			
		|||
	if (!whiteout)
 | 
			
		||||
		return -ENOMEM;
 | 
			
		||||
 | 
			
		||||
	error = shmem_mknod(&nop_mnt_idmap, old_dir, whiteout,
 | 
			
		||||
	error = shmem_mknod(idmap, old_dir, whiteout,
 | 
			
		||||
			    S_IFCHR | WHITEOUT_MODE, WHITEOUT_DEV);
 | 
			
		||||
	dput(whiteout);
 | 
			
		||||
	if (error)
 | 
			
		||||
| 
						 | 
				
			
			@ -3098,7 +3099,7 @@ static int shmem_rename2(struct mnt_idmap *idmap,
 | 
			
		|||
	if (flags & RENAME_WHITEOUT) {
 | 
			
		||||
		int error;
 | 
			
		||||
 | 
			
		||||
		error = shmem_whiteout(&nop_mnt_idmap, old_dir, old_dentry);
 | 
			
		||||
		error = shmem_whiteout(idmap, old_dir, old_dentry);
 | 
			
		||||
		if (error)
 | 
			
		||||
			return error;
 | 
			
		||||
	}
 | 
			
		||||
| 
						 | 
				
			
			@ -3136,7 +3137,7 @@ static int shmem_symlink(struct mnt_idmap *idmap, struct inode *dir,
 | 
			
		|||
	if (len > PAGE_SIZE)
 | 
			
		||||
		return -ENAMETOOLONG;
 | 
			
		||||
 | 
			
		||||
	inode = shmem_get_inode(dir->i_sb, dir, S_IFLNK | 0777, 0,
 | 
			
		||||
	inode = shmem_get_inode(idmap, dir->i_sb, dir, S_IFLNK | 0777, 0,
 | 
			
		||||
				VM_NORESERVE);
 | 
			
		||||
	if (!inode)
 | 
			
		||||
		return -ENOSPC;
 | 
			
		||||
| 
						 | 
				
			
			@ -3819,7 +3820,8 @@ static int shmem_fill_super(struct super_block *sb, struct fs_context *fc)
 | 
			
		|||
#endif
 | 
			
		||||
	uuid_gen(&sb->s_uuid);
 | 
			
		||||
 | 
			
		||||
	inode = shmem_get_inode(sb, NULL, S_IFDIR | sbinfo->mode, 0, VM_NORESERVE);
 | 
			
		||||
	inode = shmem_get_inode(&nop_mnt_idmap, sb, NULL, S_IFDIR | sbinfo->mode, 0,
 | 
			
		||||
				VM_NORESERVE);
 | 
			
		||||
	if (!inode)
 | 
			
		||||
		goto failed;
 | 
			
		||||
	inode->i_uid = sbinfo->uid;
 | 
			
		||||
| 
						 | 
				
			
			@ -4044,7 +4046,11 @@ static struct file_system_type shmem_fs_type = {
 | 
			
		|||
	.parameters	= shmem_fs_parameters,
 | 
			
		||||
#endif
 | 
			
		||||
	.kill_sb	= kill_litter_super,
 | 
			
		||||
#ifdef CONFIG_SHMEM
 | 
			
		||||
	.fs_flags	= FS_USERNS_MOUNT | FS_ALLOW_IDMAP,
 | 
			
		||||
#else
 | 
			
		||||
	.fs_flags	= FS_USERNS_MOUNT,
 | 
			
		||||
#endif
 | 
			
		||||
};
 | 
			
		||||
 | 
			
		||||
void __init shmem_init(void)
 | 
			
		||||
| 
						 | 
				
			
			@ -4196,7 +4202,7 @@ EXPORT_SYMBOL_GPL(shmem_truncate_range);
 | 
			
		|||
#define shmem_vm_ops				generic_file_vm_ops
 | 
			
		||||
#define shmem_anon_vm_ops			generic_file_vm_ops
 | 
			
		||||
#define shmem_file_operations			ramfs_file_operations
 | 
			
		||||
#define shmem_get_inode(sb, dir, mode, dev, flags)	ramfs_get_inode(sb, dir, mode, dev)
 | 
			
		||||
#define shmem_get_inode(idmap, sb, dir, mode, dev, flags) ramfs_get_inode(sb, dir, mode, dev)
 | 
			
		||||
#define shmem_acct_size(flags, size)		0
 | 
			
		||||
#define shmem_unacct_size(flags, size)		do {} while (0)
 | 
			
		||||
 | 
			
		||||
| 
						 | 
				
			
			@ -4219,8 +4225,11 @@ static struct file *__shmem_file_setup(struct vfsmount *mnt, const char *name, l
 | 
			
		|||
	if (shmem_acct_size(flags, size))
 | 
			
		||||
		return ERR_PTR(-ENOMEM);
 | 
			
		||||
 | 
			
		||||
	inode = shmem_get_inode(mnt->mnt_sb, NULL, S_IFREG | S_IRWXUGO, 0,
 | 
			
		||||
				flags);
 | 
			
		||||
	if (is_idmapped_mnt(mnt))
 | 
			
		||||
		return ERR_PTR(-EINVAL);
 | 
			
		||||
 | 
			
		||||
	inode = shmem_get_inode(&nop_mnt_idmap, mnt->mnt_sb, NULL,
 | 
			
		||||
				S_IFREG | S_IRWXUGO, 0, flags);
 | 
			
		||||
	if (unlikely(!inode)) {
 | 
			
		||||
		shmem_unacct_size(flags, size);
 | 
			
		||||
		return ERR_PTR(-ENOSPC);
 | 
			
		||||
| 
						 | 
				
			
			
 | 
			
		|||
		Loading…
	
		Reference in a new issue