mirror of
				https://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson
				synced 2025-10-31 18:53:24 +00:00 
			
		
		
		
	 796bd95247
			
		
	
	
		796bd95247
		
	
	
	
	
		
			
			This is required for cluster filesystems which want to use cached ACLs so that they can invalidate the cache when required. Signed-off-by: Steven Whitehouse <swhiteho@redhat.com> Cc: Alexander Viro <aviro@redhat.com> Cc: Christoph Hellwig <hch@infradead.org>
		
			
				
	
	
		
			175 lines
		
	
	
		
			3.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			175 lines
		
	
	
		
			3.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
 | |
|   File: linux/posix_acl.h
 | |
| 
 | |
|   (C) 2002 Andreas Gruenbacher, <a.gruenbacher@computer.org>
 | |
| */
 | |
| 
 | |
| 
 | |
| #ifndef __LINUX_POSIX_ACL_H
 | |
| #define __LINUX_POSIX_ACL_H
 | |
| 
 | |
| #include <linux/slab.h>
 | |
| 
 | |
| #define ACL_UNDEFINED_ID	(-1)
 | |
| 
 | |
| /* a_type field in acl_user_posix_entry_t */
 | |
| #define ACL_TYPE_ACCESS		(0x8000)
 | |
| #define ACL_TYPE_DEFAULT	(0x4000)
 | |
| 
 | |
| /* e_tag entry in struct posix_acl_entry */
 | |
| #define ACL_USER_OBJ		(0x01)
 | |
| #define ACL_USER		(0x02)
 | |
| #define ACL_GROUP_OBJ		(0x04)
 | |
| #define ACL_GROUP		(0x08)
 | |
| #define ACL_MASK		(0x10)
 | |
| #define ACL_OTHER		(0x20)
 | |
| 
 | |
| /* permissions in the e_perm field */
 | |
| #define ACL_READ		(0x04)
 | |
| #define ACL_WRITE		(0x02)
 | |
| #define ACL_EXECUTE		(0x01)
 | |
| //#define ACL_ADD		(0x08)
 | |
| //#define ACL_DELETE		(0x10)
 | |
| 
 | |
| struct posix_acl_entry {
 | |
| 	short			e_tag;
 | |
| 	unsigned short		e_perm;
 | |
| 	unsigned int		e_id;
 | |
| };
 | |
| 
 | |
| struct posix_acl {
 | |
| 	atomic_t		a_refcount;
 | |
| 	unsigned int		a_count;
 | |
| 	struct posix_acl_entry	a_entries[0];
 | |
| };
 | |
| 
 | |
| #define FOREACH_ACL_ENTRY(pa, acl, pe) \
 | |
| 	for(pa=(acl)->a_entries, pe=pa+(acl)->a_count; pa<pe; pa++)
 | |
| 
 | |
| 
 | |
| /*
 | |
|  * Duplicate an ACL handle.
 | |
|  */
 | |
| static inline struct posix_acl *
 | |
| posix_acl_dup(struct posix_acl *acl)
 | |
| {
 | |
| 	if (acl)
 | |
| 		atomic_inc(&acl->a_refcount);
 | |
| 	return acl;
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Free an ACL handle.
 | |
|  */
 | |
| static inline void
 | |
| posix_acl_release(struct posix_acl *acl)
 | |
| {
 | |
| 	if (acl && atomic_dec_and_test(&acl->a_refcount))
 | |
| 		kfree(acl);
 | |
| }
 | |
| 
 | |
| 
 | |
| /* posix_acl.c */
 | |
| 
 | |
| extern struct posix_acl *posix_acl_alloc(int, gfp_t);
 | |
| extern struct posix_acl *posix_acl_clone(const struct posix_acl *, gfp_t);
 | |
| extern int posix_acl_valid(const struct posix_acl *);
 | |
| extern int posix_acl_permission(struct inode *, const struct posix_acl *, int);
 | |
| extern struct posix_acl *posix_acl_from_mode(mode_t, gfp_t);
 | |
| extern int posix_acl_equiv_mode(const struct posix_acl *, mode_t *);
 | |
| extern int posix_acl_create_masq(struct posix_acl *, mode_t *);
 | |
| extern int posix_acl_chmod_masq(struct posix_acl *, mode_t);
 | |
| 
 | |
| extern struct posix_acl *get_posix_acl(struct inode *, int);
 | |
| extern int set_posix_acl(struct inode *, int, struct posix_acl *);
 | |
| 
 | |
| #ifdef CONFIG_FS_POSIX_ACL
 | |
| static inline struct posix_acl *get_cached_acl(struct inode *inode, int type)
 | |
| {
 | |
| 	struct posix_acl **p, *acl;
 | |
| 	switch (type) {
 | |
| 	case ACL_TYPE_ACCESS:
 | |
| 		p = &inode->i_acl;
 | |
| 		break;
 | |
| 	case ACL_TYPE_DEFAULT:
 | |
| 		p = &inode->i_default_acl;
 | |
| 		break;
 | |
| 	default:
 | |
| 		return ERR_PTR(-EINVAL);
 | |
| 	}
 | |
| 	acl = ACCESS_ONCE(*p);
 | |
| 	if (acl) {
 | |
| 		spin_lock(&inode->i_lock);
 | |
| 		acl = *p;
 | |
| 		if (acl != ACL_NOT_CACHED)
 | |
| 			acl = posix_acl_dup(acl);
 | |
| 		spin_unlock(&inode->i_lock);
 | |
| 	}
 | |
| 	return acl;
 | |
| }
 | |
| 
 | |
| static inline void set_cached_acl(struct inode *inode,
 | |
| 				  int type,
 | |
| 				  struct posix_acl *acl)
 | |
| {
 | |
| 	struct posix_acl *old = NULL;
 | |
| 	spin_lock(&inode->i_lock);
 | |
| 	switch (type) {
 | |
| 	case ACL_TYPE_ACCESS:
 | |
| 		old = inode->i_acl;
 | |
| 		inode->i_acl = posix_acl_dup(acl);
 | |
| 		break;
 | |
| 	case ACL_TYPE_DEFAULT:
 | |
| 		old = inode->i_default_acl;
 | |
| 		inode->i_default_acl = posix_acl_dup(acl);
 | |
| 		break;
 | |
| 	}
 | |
| 	spin_unlock(&inode->i_lock);
 | |
| 	if (old != ACL_NOT_CACHED)
 | |
| 		posix_acl_release(old);
 | |
| }
 | |
| 
 | |
| static inline void forget_cached_acl(struct inode *inode, int type)
 | |
| {
 | |
| 	struct posix_acl *old = NULL;
 | |
| 	spin_lock(&inode->i_lock);
 | |
| 	switch (type) {
 | |
| 	case ACL_TYPE_ACCESS:
 | |
| 		old = inode->i_acl;
 | |
| 		inode->i_acl = ACL_NOT_CACHED;
 | |
| 		break;
 | |
| 	case ACL_TYPE_DEFAULT:
 | |
| 		old = inode->i_default_acl;
 | |
| 		inode->i_default_acl = ACL_NOT_CACHED;
 | |
| 		break;
 | |
| 	}
 | |
| 	spin_unlock(&inode->i_lock);
 | |
| 	if (old != ACL_NOT_CACHED)
 | |
| 		posix_acl_release(old);
 | |
| }
 | |
| 
 | |
| static inline void forget_all_cached_acls(struct inode *inode)
 | |
| {
 | |
| 	struct posix_acl *old_access, *old_default;
 | |
| 	spin_lock(&inode->i_lock);
 | |
| 	old_access = inode->i_acl;
 | |
| 	old_default = inode->i_default_acl;
 | |
| 	inode->i_acl = inode->i_default_acl = ACL_NOT_CACHED;
 | |
| 	spin_unlock(&inode->i_lock);
 | |
| 	if (old_access != ACL_NOT_CACHED)
 | |
| 		posix_acl_release(old_access);
 | |
| 	if (old_default != ACL_NOT_CACHED)
 | |
| 		posix_acl_release(old_default);
 | |
| }
 | |
| #endif
 | |
| 
 | |
| static inline void cache_no_acl(struct inode *inode)
 | |
| {
 | |
| #ifdef CONFIG_FS_POSIX_ACL
 | |
| 	inode->i_acl = NULL;
 | |
| 	inode->i_default_acl = NULL;
 | |
| #endif
 | |
| }
 | |
| 
 | |
| #endif  /* __LINUX_POSIX_ACL_H */
 |