diff options
Diffstat (limited to 'libblkid/src/superblocks/xfs.c')
| -rw-r--r-- | libblkid/src/superblocks/xfs.c | 277 |
1 files changed, 277 insertions, 0 deletions
diff --git a/libblkid/src/superblocks/xfs.c b/libblkid/src/superblocks/xfs.c new file mode 100644 index 000000000..a6c04a2f0 --- /dev/null +++ b/libblkid/src/superblocks/xfs.c @@ -0,0 +1,277 @@ +/* + * 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, +}; |