summaryrefslogtreecommitdiffstats
path: root/libblkid/src/superblocks/xfs.c
diff options
context:
space:
mode:
Diffstat (limited to '')
-rw-r--r--libblkid/src/superblocks/xfs.c284
1 files changed, 284 insertions, 0 deletions
diff --git a/libblkid/src/superblocks/xfs.c b/libblkid/src/superblocks/xfs.c
new file mode 100644
index 0000000..99848f9
--- /dev/null
+++ b/libblkid/src/superblocks/xfs.c
@@ -0,0 +1,284 @@
+/*
+ * 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 != (1ULL << 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 (*xs->sb_fname != '\0')
+ 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 __attribute__((__unused__)))
+{
+ 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");
+
+ if (blkid_probe_set_magic(pr, i * 512,
+ sizeof(rhead->h_magicno),
+ (unsigned char *) &rhead->h_magicno))
+ return 1;
+
+ 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,
+};