1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * Copyright (c) 2000,2002-2003,2005 Silicon Graphics, Inc. 4 * All Rights Reserved. 5 */ 6 #ifndef __XFS_ATTR_H__ 7 #define __XFS_ATTR_H__ 8 9 struct xfs_inode; 10 struct xfs_da_args; 11 struct xfs_attr_list_context; 12 13 /* 14 * Large attribute lists are structured around Btrees where all the data 15 * elements are in the leaf nodes. Attribute names are hashed into an int, 16 * then that int is used as the index into the Btree. Since the hashval 17 * of an attribute name may not be unique, we may have duplicate keys. 18 * The internal links in the Btree are logical block offsets into the file. 19 * 20 * Small attribute lists use a different format and are packed as tightly 21 * as possible so as to fit into the literal area of the inode. 22 */ 23 24 /* 25 * The maximum size (into the kernel or returned from the kernel) of an 26 * attribute value or the buffer used for an attr_list() call. Larger 27 * sizes will result in an ERANGE return code. 28 */ 29 #define ATTR_MAX_VALUELEN (64*1024) /* max length of a value */ 30 31 /* 32 * Kernel-internal version of the attrlist cursor. 33 */ 34 struct xfs_attrlist_cursor_kern { 35 __u32 hashval; /* hash value of next entry to add */ 36 __u32 blkno; /* block containing entry (suggestion) */ 37 __u32 offset; /* offset in list of equal-hashvals */ 38 __u16 pad1; /* padding to match user-level */ 39 __u8 pad2; /* padding to match user-level */ 40 __u8 initted; /* T/F: cursor has been initialized */ 41 }; 42 43 44 /*======================================================================== 45 * Structure used to pass context around among the routines. 46 *========================================================================*/ 47 48 49 /* void; state communicated via *context */ 50 typedef void (*put_listent_func_t)(struct xfs_attr_list_context *, int, 51 unsigned char *, int, int); 52 53 struct xfs_attr_list_context { 54 struct xfs_trans *tp; 55 struct xfs_inode *dp; /* inode */ 56 struct xfs_attrlist_cursor_kern cursor; /* position in list */ 57 void *buffer; /* output buffer */ 58 59 /* 60 * Abort attribute list iteration if non-zero. Can be used to pass 61 * error values to the xfs_attr_list caller. 62 */ 63 int seen_enough; 64 bool allow_incomplete; 65 66 ssize_t count; /* num used entries */ 67 int dupcnt; /* count dup hashvals seen */ 68 int bufsize; /* total buffer size */ 69 int firstu; /* first used byte in buffer */ 70 unsigned int attr_filter; /* XFS_ATTR_{ROOT,SECURE} */ 71 int resynch; /* T/F: resynch with cursor */ 72 put_listent_func_t put_listent; /* list output fmt function */ 73 int index; /* index into output buffer */ 74 }; 75 76 77 /*======================================================================== 78 * Function prototypes for the kernel. 79 *========================================================================*/ 80 81 /* 82 * Overall external interface routines. 83 */ 84 int xfs_attr_inactive(struct xfs_inode *dp); 85 int xfs_attr_list_ilocked(struct xfs_attr_list_context *); 86 int xfs_attr_list(struct xfs_attr_list_context *); 87 int xfs_inode_hasattr(struct xfs_inode *ip); 88 int xfs_attr_get_ilocked(struct xfs_da_args *args); 89 int xfs_attr_get(struct xfs_da_args *args); 90 int xfs_attr_set(struct xfs_da_args *args); 91 int xfs_attr_set_args(struct xfs_da_args *args); 92 int xfs_attr_remove_args(struct xfs_da_args *args); 93 bool xfs_attr_namecheck(const void *name, size_t length); 94 95 #endif /* __XFS_ATTR_H__ */ 96