freebsd-dev/sys/geom/label/g_label.h
Pawel Jakub Dawidek e68909854c - Add md_provsize field to metadata, which will help with
shared-last-sector problem.
  After this change, even if there is more than one provider with the same
  last sector, the proper one will be chosen based on its size.
  It still doesn't fix the 'c' partition problem (when da0s1 can be confused
  with da0s1c) and situation when 'a' partition starts at offset 0
  (then da0s1a can be confused with da0s1 and da0s1c). One can use '-h'
  option there, when creating device or avoid sharing last sector.
  Actually, when providers share the same last sector and their size is equal,
  they provide exactly the same data, so the name (da0s1, da0s1a, da0s1c)
  isn't important at all.
- Provide backward compatibility.
- Update copyright's year.

MFC after:	1 week
2005-02-27 23:07:47 +00:00

97 lines
3.1 KiB
C

/*-
* Copyright (c) 2004-2005 Pawel Jakub Dawidek <pjd@FreeBSD.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#ifndef _G_LABEL_H_
#define _G_LABEL_H_
#include <sys/endian.h>
#define G_LABEL_CLASS_NAME "LABEL"
#define G_LABEL_MAGIC "GEOM::LABEL"
/*
* Version history:
* 1 - Initial version number.
* 2 - Added md_provsize field to metadata.
*/
#define G_LABEL_VERSION 2
#define G_LABEL_DIR "label"
#ifdef _KERNEL
extern u_int g_label_debug;
#define G_LABEL_DEBUG(lvl, ...) do { \
if (g_label_debug >= (lvl)) { \
printf("GEOM_LABEL"); \
if (g_label_debug > 0) \
printf("[%u]", lvl); \
printf(": "); \
printf(__VA_ARGS__); \
printf("\n"); \
} \
} while (0)
typedef void g_label_taste_t (struct g_consumer *cp, char *label, size_t size);
struct g_label_desc {
g_label_taste_t *ld_taste;
char *ld_dir;
};
/* Supported labels. */
extern const struct g_label_desc g_label_ufs;
extern const struct g_label_desc g_label_iso9660;
extern const struct g_label_desc g_label_msdosfs;
#endif /* _KERNEL */
struct g_label_metadata {
char md_magic[16]; /* Magic value. */
uint32_t md_version; /* Version number. */
char md_label[16]; /* Label. */
uint64_t md_provsize; /* Provider's size. */
};
static __inline void
label_metadata_encode(const struct g_label_metadata *md, u_char *data)
{
bcopy(md->md_magic, data, sizeof(md->md_magic));
le32enc(data + 16, md->md_version);
bcopy(md->md_label, data + 20, sizeof(md->md_label));
le64enc(data + 36, md->md_provsize);
}
static __inline void
label_metadata_decode(const u_char *data, struct g_label_metadata *md)
{
bcopy(data, md->md_magic, sizeof(md->md_magic));
md->md_version = le32dec(data + 16);
bcopy(data + 20, md->md_label, sizeof(md->md_label));
md->md_provsize = le64dec(data + 36);
}
#endif /* _G_LABEL_H_ */