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/*
* Copyright (C) 1999 by Andries Brouwer
* Copyright (C) 1999, 2000, 2003 by Theodore Ts'o
* Copyright (C) 2001 by Andreas Dilger
* Copyright (C) 2004 Kay Sievers <kay.sievers@vrfy.org>
* Copyright (C) 2008 Karel Zak <kzak@redhat.com>
* Copyright (C) 2013 Eric Sandeen <sandeen@redhat.com>
*
* This file may be redistributed under the terms of the
* GNU Lesser General Public License.
*/
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <errno.h>
#include <ctype.h>
#include <stdint.h>
#include "superblocks.h"
struct xfs_super_block {
uint32_t sb_magicnum; /* magic number == XFS_SB_MAGIC */
uint32_t sb_blocksize; /* logical block size, bytes */
uint64_t sb_dblocks; /* number of data blocks */
uint64_t sb_rblocks; /* number of realtime blocks */
uint64_t sb_rextents; /* number of realtime extents */
unsigned char sb_uuid[16]; /* file system unique id */
uint64_t sb_logstart; /* starting block of log if internal */
uint64_t sb_rootino; /* root inode number */
uint64_t sb_rbmino; /* bitmap inode for realtime extents */
uint64_t sb_rsumino; /* summary inode for rt bitmap */
uint32_t sb_rextsize; /* realtime extent size, blocks */
uint32_t sb_agblocks; /* size of an allocation group */
uint32_t sb_agcount; /* number of allocation groups */
uint32_t sb_rbmblocks; /* number of rt bitmap blocks */
uint32_t sb_logblocks; /* number of log blocks */
uint16_t sb_versionnum; /* header version == XFS_SB_VERSION */
uint16_t sb_sectsize; /* volume sector size, bytes */
uint16_t sb_inodesize; /* inode size, bytes */
uint16_t sb_inopblock; /* inodes per block */
char sb_fname[12]; /* file system name */
uint8_t sb_blocklog; /* log2 of sb_blocksize */
uint8_t sb_sectlog; /* log2 of sb_sectsize */
uint8_t sb_inodelog; /* log2 of sb_inodesize */
uint8_t sb_inopblog; /* log2 of sb_inopblock */
uint8_t sb_agblklog; /* log2 of sb_agblocks (rounded up) */
uint8_t sb_rextslog; /* log2 of sb_rextents */
uint8_t sb_inprogress; /* mkfs is in progress, don't mount */
uint8_t sb_imax_pct; /* max % of fs for inode space */
/* statistics */
uint64_t sb_icount; /* allocated inodes */
uint64_t sb_ifree; /* free inodes */
uint64_t sb_fdblocks; /* free data blocks */
uint64_t sb_frextents; /* free realtime extents */
/* this is not all... but enough for libblkid */
} __attribute__((packed));
#define XFS_MIN_BLOCKSIZE_LOG 9 /* i.e. 512 bytes */
#define XFS_MAX_BLOCKSIZE_LOG 16 /* i.e. 65536 bytes */
#define XFS_MIN_BLOCKSIZE (1 << XFS_MIN_BLOCKSIZE_LOG)
#define XFS_MAX_BLOCKSIZE (1 << XFS_MAX_BLOCKSIZE_LOG)
#define XFS_MIN_SECTORSIZE_LOG 9 /* i.e. 512 bytes */
#define XFS_MAX_SECTORSIZE_LOG 15 /* i.e. 32768 bytes */
#define XFS_MIN_SECTORSIZE (1 << XFS_MIN_SECTORSIZE_LOG)
#define XFS_MAX_SECTORSIZE (1 << XFS_MAX_SECTORSIZE_LOG)
#define XFS_DINODE_MIN_LOG 8
#define XFS_DINODE_MAX_LOG 11
#define XFS_DINODE_MIN_SIZE (1 << XFS_DINODE_MIN_LOG)
#define XFS_DINODE_MAX_SIZE (1 << XFS_DINODE_MAX_LOG)
#define XFS_MAX_RTEXTSIZE (1024 * 1024 * 1024) /* 1GB */
#define XFS_DFL_RTEXTSIZE (64 * 1024) /* 64kB */
#define XFS_MIN_RTEXTSIZE (4 * 1024) /* 4kB */
#define XFS_MIN_AG_BLOCKS 64
#define XFS_MAX_DBLOCKS(s) ((uint64_t)(s)->sb_agcount * (s)->sb_agblocks)
#define XFS_MIN_DBLOCKS(s) ((uint64_t)((s)->sb_agcount - 1) * \
(s)->sb_agblocks + XFS_MIN_AG_BLOCKS)
static void sb_from_disk(struct xfs_super_block *from,
struct xfs_super_block *to)
{
to->sb_magicnum = be32_to_cpu(from->sb_magicnum);
to->sb_blocksize = be32_to_cpu(from->sb_blocksize);
to->sb_dblocks = be64_to_cpu(from->sb_dblocks);
to->sb_rblocks = be64_to_cpu(from->sb_rblocks);
to->sb_rextents = be64_to_cpu(from->sb_rextents);
to->sb_logstart = be64_to_cpu(from->sb_logstart);
to->sb_rootino = be64_to_cpu(from->sb_rootino);
to->sb_rbmino = be64_to_cpu(from->sb_rbmino);
to->sb_rsumino = be64_to_cpu(from->sb_rsumino);
to->sb_rextsize = be32_to_cpu(from->sb_rextsize);
to->sb_agblocks = be32_to_cpu(from->sb_agblocks);
to->sb_agcount = be32_to_cpu(from->sb_agcount);
to->sb_rbmblocks = be32_to_cpu(from->sb_rbmblocks);
to->sb_logblocks = be32_to_cpu(from->sb_logblocks);
to->sb_versionnum = be16_to_cpu(from->sb_versionnum);
to->sb_sectsize = be16_to_cpu(from->sb_sectsize);
to->sb_inodesize = be16_to_cpu(from->sb_inodesize);
to->sb_inopblock = be16_to_cpu(from->sb_inopblock);
to->sb_blocklog = from->sb_blocklog;
to->sb_sectlog = from->sb_sectlog;
to->sb_inodelog = from->sb_inodelog;
to->sb_inopblog = from->sb_inopblog;
to->sb_agblklog = from->sb_agblklog;
to->sb_rextslog = from->sb_rextslog;
to->sb_inprogress = from->sb_inprogress;
to->sb_imax_pct = from->sb_imax_pct;
to->sb_icount = be64_to_cpu(from->sb_icount);
to->sb_ifree = be64_to_cpu(from->sb_ifree);
to->sb_fdblocks = be64_to_cpu(from->sb_fdblocks);
to->sb_frextents = be64_to_cpu(from->sb_frextents);
}
static int xfs_verify_sb(struct xfs_super_block *ondisk)
{
struct xfs_super_block sb, *sbp = &sb;
/* beXX_to_cpu(), but don't convert UUID and fsname! */
sb_from_disk(ondisk, sbp);
/* sanity checks, we don't want to rely on magic string only */
if (sbp->sb_agcount <= 0 ||
sbp->sb_sectsize < XFS_MIN_SECTORSIZE ||
sbp->sb_sectsize > XFS_MAX_SECTORSIZE ||
sbp->sb_sectlog < XFS_MIN_SECTORSIZE_LOG ||
sbp->sb_sectlog > XFS_MAX_SECTORSIZE_LOG ||
sbp->sb_sectsize != (1 << sbp->sb_sectlog) ||
sbp->sb_blocksize < XFS_MIN_BLOCKSIZE ||
sbp->sb_blocksize > XFS_MAX_BLOCKSIZE ||
sbp->sb_blocklog < XFS_MIN_BLOCKSIZE_LOG ||
sbp->sb_blocklog > XFS_MAX_BLOCKSIZE_LOG ||
sbp->sb_blocksize != (1 << sbp->sb_blocklog) ||
sbp->sb_inodesize < XFS_DINODE_MIN_SIZE ||
sbp->sb_inodesize > XFS_DINODE_MAX_SIZE ||
sbp->sb_inodelog < XFS_DINODE_MIN_LOG ||
sbp->sb_inodelog > XFS_DINODE_MAX_LOG ||
sbp->sb_inodesize != (1 << sbp->sb_inodelog) ||
(sbp->sb_blocklog - sbp->sb_inodelog != sbp->sb_inopblog) ||
(sbp->sb_rextsize * sbp->sb_blocksize > XFS_MAX_RTEXTSIZE) ||
(sbp->sb_rextsize * sbp->sb_blocksize < XFS_MIN_RTEXTSIZE) ||
(sbp->sb_imax_pct > 100 /* zero sb_imax_pct is valid */) ||
sbp->sb_dblocks == 0 ||
sbp->sb_dblocks > XFS_MAX_DBLOCKS(sbp) ||
sbp->sb_dblocks < XFS_MIN_DBLOCKS(sbp))
return 0;
/* TODO: version 5 has also checksum CRC32, maybe we can check it too */
return 1;
}
static int probe_xfs(blkid_probe pr, const struct blkid_idmag *mag)
{
struct xfs_super_block *xs;
xs = blkid_probe_get_sb(pr, mag, struct xfs_super_block);
if (!xs)
return errno ? -errno : 1;
if (!xfs_verify_sb(xs))
return 1;
if (strlen(xs->sb_fname))
blkid_probe_set_label(pr, (unsigned char *) xs->sb_fname,
sizeof(xs->sb_fname));
blkid_probe_set_uuid(pr, xs->sb_uuid);
return 0;
}
const struct blkid_idinfo xfs_idinfo =
{
.name = "xfs",
.usage = BLKID_USAGE_FILESYSTEM,
.probefunc = probe_xfs,
.magics =
{
{ .magic = "XFSB", .len = 4 },
{ NULL }
}
};
struct xlog_rec_header {
uint32_t h_magicno;
uint32_t h_dummy1[1];
uint32_t h_version;
uint32_t h_len;
uint32_t h_dummy2[71];
uint32_t h_fmt;
unsigned char h_uuid[16];
} __attribute__((packed));
#define XLOG_HEADER_MAGIC_NUM 0xFEEDbabe
/*
* For very small filesystems, the minimum log size
* can be smaller, but that seems vanishingly unlikely
* when used with an external log (which is used for
* performance reasons; tiny conflicts with that goal).
*/
#define XFS_MIN_LOG_BYTES (10 * 1024 * 1024)
#define XLOG_FMT_LINUX_LE 1
#define XLOG_FMT_LINUX_BE 2
#define XLOG_FMT_IRIX_BE 3
#define XLOG_VERSION_1 1
#define XLOG_VERSION_2 2 /* Large IClogs, Log sunit */
#define XLOG_VERSION_OKBITS (XLOG_VERSION_1 | XLOG_VERSION_2)
static int xlog_valid_rec_header(struct xlog_rec_header *rhead)
{
uint32_t hlen;
if (rhead->h_magicno != cpu_to_be32(XLOG_HEADER_MAGIC_NUM))
return 0;
if (!rhead->h_version ||
(be32_to_cpu(rhead->h_version) & (~XLOG_VERSION_OKBITS)))
return 0;
/* LR body must have data or it wouldn't have been written */
hlen = be32_to_cpu(rhead->h_len);
if (hlen <= 0 || hlen > INT_MAX)
return 0;
if (rhead->h_fmt != cpu_to_be32(XLOG_FMT_LINUX_LE) &&
rhead->h_fmt != cpu_to_be32(XLOG_FMT_LINUX_BE) &&
rhead->h_fmt != cpu_to_be32(XLOG_FMT_IRIX_BE))
return 0;
return 1;
}
/* xlog record header will be in some sector in the first 256k */
static int probe_xfs_log(blkid_probe pr, const struct blkid_idmag *mag)
{
int i;
struct xlog_rec_header *rhead;
unsigned char *buf;
buf = blkid_probe_get_buffer(pr, 0, 256*1024);
if (!buf)
return errno ? -errno : 1;
if (memcmp(buf, "XFSB", 4) == 0)
return 1; /* this is regular XFS, ignore */
/* check the first 512 512-byte sectors */
for (i = 0; i < 512; i++) {
rhead = (struct xlog_rec_header *)&buf[i*512];
if (xlog_valid_rec_header(rhead)) {
blkid_probe_set_uuid_as(pr, rhead->h_uuid, "LOGUUID");
return 0;
}
}
return 1;
}
const struct blkid_idinfo xfs_log_idinfo =
{
.name = "xfs_external_log",
.usage = BLKID_USAGE_OTHER,
.probefunc = probe_xfs_log,
.magics = BLKID_NONE_MAGIC,
.minsz = XFS_MIN_LOG_BYTES,
};
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