--- /dev/null
+/*
+ * Copyright (c) 2000,2002-2003,2005 Silicon Graphics, Inc.
+ * All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it would be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+#ifndef __XFS_ATTR_H__
+#define __XFS_ATTR_H__
+
+struct xfs_inode;
+struct xfs_da_args;
+struct xfs_attr_list_context;
+
+/*
+ * Large attribute lists are structured around Btrees where all the data
+ * elements are in the leaf nodes. Attribute names are hashed into an int,
+ * then that int is used as the index into the Btree. Since the hashval
+ * of an attribute name may not be unique, we may have duplicate keys.
+ * The internal links in the Btree are logical block offsets into the file.
+ *
+ * Small attribute lists use a different format and are packed as tightly
+ * as possible so as to fit into the literal area of the inode.
+ */
+
+/*========================================================================
+ * External interfaces
+ *========================================================================*/
+
+
+#define ATTR_DONTFOLLOW 0x0001 /* -- unused, from IRIX -- */
+#define ATTR_ROOT 0x0002 /* use attrs in root (trusted) namespace */
+#define ATTR_TRUST 0x0004 /* -- unused, from IRIX -- */
+#define ATTR_SECURE 0x0008 /* use attrs in security namespace */
+#define ATTR_CREATE 0x0010 /* pure create: fail if attr already exists */
+#define ATTR_REPLACE 0x0020 /* pure set: fail if attr does not exist */
+
+#define ATTR_KERNOTIME 0x1000 /* [kernel] don't update inode timestamps */
+#define ATTR_KERNOVAL 0x2000 /* [kernel] get attr size only, not value */
+
+#define XFS_ATTR_FLAGS \
+ { ATTR_DONTFOLLOW, "DONTFOLLOW" }, \
+ { ATTR_ROOT, "ROOT" }, \
+ { ATTR_TRUST, "TRUST" }, \
+ { ATTR_SECURE, "SECURE" }, \
+ { ATTR_CREATE, "CREATE" }, \
+ { ATTR_REPLACE, "REPLACE" }, \
+ { ATTR_KERNOTIME, "KERNOTIME" }, \
+ { ATTR_KERNOVAL, "KERNOVAL" }
+
+/*
+ * The maximum size (into the kernel or returned from the kernel) of an
+ * attribute value or the buffer used for an attr_list() call. Larger
+ * sizes will result in an ERANGE return code.
+ */
+#define ATTR_MAX_VALUELEN (64*1024) /* max length of a value */
+
+/*
+ * Define how lists of attribute names are returned to the user from
+ * the attr_list() call. A large, 32bit aligned, buffer is passed in
+ * along with its size. We put an array of offsets at the top that each
+ * reference an attrlist_ent_t and pack the attrlist_ent_t's at the bottom.
+ */
+typedef struct attrlist {
+ __s32 al_count; /* number of entries in attrlist */
+ __s32 al_more; /* T/F: more attrs (do call again) */
+ __s32 al_offset[1]; /* byte offsets of attrs [var-sized] */
+} attrlist_t;
+
+/*
+ * Show the interesting info about one attribute. This is what the
+ * al_offset[i] entry points to.
+ */
+typedef struct attrlist_ent { /* data from attr_list() */
+ __u32 a_valuelen; /* number bytes in value of attr */
+ char a_name[1]; /* attr name (NULL terminated) */
+} attrlist_ent_t;
+
+/*
+ * Given a pointer to the (char*) buffer containing the attr_list() result,
+ * and an index, return a pointer to the indicated attribute in the buffer.
+ */
+#define ATTR_ENTRY(buffer, index) \
+ ((attrlist_ent_t *) \
+ &((char *)buffer)[ ((attrlist_t *)(buffer))->al_offset[index] ])
+
+/*
+ * Kernel-internal version of the attrlist cursor.
+ */
+typedef struct attrlist_cursor_kern {
+ __u32 hashval; /* hash value of next entry to add */
+ __u32 blkno; /* block containing entry (suggestion) */
+ __u32 offset; /* offset in list of equal-hashvals */
+ __u16 pad1; /* padding to match user-level */
+ __u8 pad2; /* padding to match user-level */
+ __u8 initted; /* T/F: cursor has been initialized */
+} attrlist_cursor_kern_t;
+
+
+/*========================================================================
+ * Structure used to pass context around among the routines.
+ *========================================================================*/
+
+
+typedef int (*put_listent_func_t)(struct xfs_attr_list_context *, int,
+ unsigned char *, int, int, unsigned char *);
+
+typedef struct xfs_attr_list_context {
+ struct xfs_inode *dp; /* inode */
+ struct attrlist_cursor_kern *cursor; /* position in list */
+ char *alist; /* output buffer */
+ int seen_enough; /* T/F: seen enough of list? */
+ ssize_t count; /* num used entries */
+ int dupcnt; /* count dup hashvals seen */
+ int bufsize; /* total buffer size */
+ int firstu; /* first used byte in buffer */
+ int flags; /* from VOP call */
+ int resynch; /* T/F: resynch with cursor */
+ int put_value; /* T/F: need value for listent */
+ put_listent_func_t put_listent; /* list output fmt function */
+ int index; /* index into output buffer */
+} xfs_attr_list_context_t;
+
+
+/*========================================================================
+ * Function prototypes for the kernel.
+ *========================================================================*/
+
+/*
+ * Overall external interface routines.
+ */
+int xfs_attr_inactive(struct xfs_inode *dp);
+int xfs_attr_list_int(struct xfs_attr_list_context *);
+int xfs_inode_hasattr(struct xfs_inode *ip);
+int xfs_attr_get(struct xfs_inode *ip, const unsigned char *name,
+ unsigned char *value, int *valuelenp, int flags);
+int xfs_attr_set(struct xfs_inode *dp, const unsigned char *name,
+ unsigned char *value, int valuelen, int flags);
+int xfs_attr_remove(struct xfs_inode *dp, const unsigned char *name, int flags);
+int xfs_attr_list(struct xfs_inode *dp, char *buffer, int bufsize,
+ int flags, struct attrlist_cursor_kern *cursor);
+
+
+#endif /* __XFS_ATTR_H__ */
Code Review / kvmfornfv.git / blobdiff