Re: [PATCH 01/21] xfsprogs: Move xfs_attr.h to libxfs

["Darrick J. Wong" <darrick.wong@oracle.com>]

On Mon, May 07, 2018 at 09:40:59PM -0700, Allison Henderson wrote:
> Subject: [PATCH 01/21] xfsprogs: Move xfs_attr.h to libxfs

For libxfs patches ported over from the kernel I just leave the subject
as is:

    xfs: Move xfs_attr.h to libxfs

so that it's more obvious which patches start the surgery on the
utilities themselves:

    mkfs.xfs: Add parent pointer flag to cmd

Also as an aside if you need to create a new patch for something that's
in libxfs but not in the kernel libxfs then I tag it as such:

    libxfs: defrobulate the widgets

--D

> This patch moves fs/xfs/xfs_attr.h to fs/xfs/libxfs/xfs_attr.h
> since xfs_attr.c is in libxfs.  We will need these later in
> xfsprogs.
> 
> Signed-off-by: Allison Henderson <allison.henderson@oracle.com>
> ---
>  libxfs/Makefile   |   1 +
>  libxfs/xfs_attr.h | 157 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
>  2 files changed, 158 insertions(+)
> 
> diff --git a/libxfs/Makefile b/libxfs/Makefile
> index 0470f5f..75ce980 100644
> --- a/libxfs/Makefile
> +++ b/libxfs/Makefile
> @@ -21,6 +21,7 @@ HFILES = \
>  	xfs_ag_resv.h \
>  	xfs_alloc.h \
>  	xfs_alloc_btree.h \
> +	xfs_attr.h \
>  	xfs_attr_leaf.h \
>  	xfs_attr_sf.h \
>  	xfs_bit.h \
> diff --git a/libxfs/xfs_attr.h b/libxfs/xfs_attr.h
> new file mode 100644
> index 0000000..8abf398
> --- /dev/null
> +++ b/libxfs/xfs_attr.h
> @@ -0,0 +1,157 @@
> +/*
> + * 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_INCOMPLETE	0x4000	/* [kernel] return INCOMPLETE attr keys */
> +
> +#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" }, \
> +	{ ATTR_INCOMPLETE,	"INCOMPLETE" }
> +
> +/*
> + * 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.
> + *========================================================================*/
> +
> +
> +/* void; state communicated via *context */
> +typedef void (*put_listent_func_t)(struct xfs_attr_list_context *, int,
> +			      unsigned char *, int, int);
> +
> +typedef struct xfs_attr_list_context {
> +	struct xfs_trans		*tp;
> +	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 */
> +	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_ilocked(struct xfs_attr_list_context *);
> +int xfs_attr_list_int(struct xfs_attr_list_context *);
> +int xfs_inode_hasattr(struct xfs_inode *ip);
> +int xfs_attr_get_ilocked(struct xfs_inode *ip, struct xfs_da_args *args);
> +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__ */
> -- 
> 2.7.4
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-xfs" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html