From e60683a0d553b6488c564863f4e48954944fb0f8 Mon Sep 17 00:00:00 2001 From: bigbiff bigbiff Date: Fri, 22 Feb 2013 20:55:50 -0500 Subject: use libblkid to get filesystem type we can now use libblkid to detect exfat --- libblkid/zfs.c | 226 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 226 insertions(+) create mode 100644 libblkid/zfs.c (limited to 'libblkid/zfs.c') diff --git a/libblkid/zfs.c b/libblkid/zfs.c new file mode 100644 index 000000000..b96c5df45 --- /dev/null +++ b/libblkid/zfs.c @@ -0,0 +1,226 @@ +/* + * Copyright (C) 2009-2010 by Andreas Dilger + * + * This file may be redistributed under the terms of the + * GNU Lesser General Public License. + */ + +#include +#include +#include +#include +#include +#include +#include + +#include "superblocks.h" + +#define VDEV_LABEL_UBERBLOCK (128 * 1024ULL) +#define VDEV_LABEL_NVPAIR ( 16 * 1024ULL) +#define VDEV_LABEL_SIZE (256 * 1024ULL) + +/* #include */ +#define UBERBLOCK_MAGIC 0x00bab10c /* oo-ba-bloc! */ +struct zfs_uberblock { + uint64_t ub_magic; /* UBERBLOCK_MAGIC */ + uint64_t ub_version; /* SPA_VERSION */ + uint64_t ub_txg; /* txg of last sync */ + uint64_t ub_guid_sum; /* sum of all vdev guids */ + uint64_t ub_timestamp; /* UTC time of last sync */ + char ub_rootbp; /* MOS objset_phys_t */ +} __attribute__((packed)); + +#define ZFS_TRIES 64 +#define ZFS_WANT 4 + +#define DATA_TYPE_UINT64 8 +#define DATA_TYPE_STRING 9 + +struct nvpair { + uint32_t nvp_size; + uint32_t nvp_unkown; + uint32_t nvp_namelen; + char nvp_name[0]; /* aligned to 4 bytes */ + /* aligned ptr array for string arrays */ + /* aligned array of data for value */ +}; + +struct nvstring { + uint32_t nvs_type; + uint32_t nvs_elem; + uint32_t nvs_strlen; + unsigned char nvs_string[0]; +}; + +struct nvuint64 { + uint32_t nvu_type; + uint32_t nvu_elem; + uint64_t nvu_value; +}; + +struct nvlist { + uint32_t nvl_unknown[3]; + struct nvpair nvl_nvpair; +}; + +#define nvdebug(fmt, ...) do { } while(0) +/*#define nvdebug(fmt, a...) printf(fmt, ##a)*/ + +static void zfs_extract_guid_name(blkid_probe pr, loff_t offset) +{ + struct nvlist *nvl; + struct nvpair *nvp; + size_t left = 4096; + int found = 0; + + offset = (offset & ~(VDEV_LABEL_SIZE - 1)) + VDEV_LABEL_NVPAIR; + + /* Note that we currently assume that the desired fields are within + * the first 4k (left) of the nvlist. This is true for all pools + * I've seen, and simplifies this code somewhat, because we don't + * have to handle an nvpair crossing a buffer boundary. */ + nvl = (struct nvlist *)blkid_probe_get_buffer(pr, offset, left); + if (nvl == NULL) + return; + + nvdebug("zfs_extract: nvlist offset %llu\n", offset); + + nvp = &nvl->nvl_nvpair; + while (left > sizeof(*nvp) && nvp->nvp_size != 0 && found < 3) { + int avail; /* tracks that name/value data fits in nvp_size */ + int namesize; + + nvp->nvp_size = be32_to_cpu(nvp->nvp_size); + nvp->nvp_namelen = be32_to_cpu(nvp->nvp_namelen); + avail = nvp->nvp_size - nvp->nvp_namelen - sizeof(*nvp); + + nvdebug("left %zd nvp_size %u\n", left, nvp->nvp_size); + if (left < nvp->nvp_size || avail < 0) + break; + + namesize = (nvp->nvp_namelen + 3) & ~3; + + nvdebug("nvlist: size %u, namelen %u, name %*s\n", + nvp->nvp_size, nvp->nvp_namelen, nvp->nvp_namelen, + nvp->nvp_name); + if (strncmp(nvp->nvp_name, "name", nvp->nvp_namelen) == 0) { + struct nvstring *nvs = (void *)(nvp->nvp_name+namesize); + + nvs->nvs_type = be32_to_cpu(nvs->nvs_type); + nvs->nvs_strlen = be32_to_cpu(nvs->nvs_strlen); + avail -= nvs->nvs_strlen + sizeof(*nvs); + nvdebug("nvstring: type %u string %*s\n", nvs->nvs_type, + nvs->nvs_strlen, nvs->nvs_string); + if (nvs->nvs_type == DATA_TYPE_STRING && avail >= 0) + blkid_probe_set_label(pr, nvs->nvs_string, + nvs->nvs_strlen); + found++; + } else if (strncmp(nvp->nvp_name, "guid", + nvp->nvp_namelen) == 0) { + struct nvuint64 *nvu = (void *)(nvp->nvp_name+namesize); + uint64_t nvu_value; + + memcpy(&nvu_value, &nvu->nvu_value, sizeof(nvu_value)); + nvu->nvu_type = be32_to_cpu(nvu->nvu_type); + nvu_value = be64_to_cpu(nvu_value); + avail -= sizeof(*nvu); + nvdebug("nvuint64: type %u value %"PRIu64"\n", + nvu->nvu_type, nvu_value); + if (nvu->nvu_type == DATA_TYPE_UINT64 && avail >= 0) + blkid_probe_sprintf_value(pr, "UUID_SUB", + "%"PRIu64, nvu_value); + found++; + } else if (strncmp(nvp->nvp_name, "pool_guid", + nvp->nvp_namelen) == 0) { + struct nvuint64 *nvu = (void *)(nvp->nvp_name+namesize); + uint64_t nvu_value; + + memcpy(&nvu_value, &nvu->nvu_value, sizeof(nvu_value)); + nvu->nvu_type = be32_to_cpu(nvu->nvu_type); + nvu_value = be64_to_cpu(nvu_value); + avail -= sizeof(*nvu); + nvdebug("nvuint64: type %u value %"PRIu64"\n", + nvu->nvu_type, nvu_value); + if (nvu->nvu_type == DATA_TYPE_UINT64 && avail >= 0) + blkid_probe_sprintf_uuid(pr, (unsigned char *) + &nvu_value, + sizeof(nvu_value), + "%"PRIu64, nvu_value); + found++; + } + if (left > nvp->nvp_size) + left -= nvp->nvp_size; + else + left = 0; + nvp = (struct nvpair *)((char *)nvp + nvp->nvp_size); + } +} + +#define zdebug(fmt, ...) do {} while(0) +/*#define zdebug(fmt, a...) printf(fmt, ##a)*/ + +/* ZFS has 128x1kB host-endian root blocks, stored in 2 areas at the start + * of the disk, and 2 areas at the end of the disk. Check only some of them... + * #4 (@ 132kB) is the first one written on a new filesystem. */ +static int probe_zfs(blkid_probe pr, + const struct blkid_idmag *mag __attribute__((__unused__))) +{ + uint64_t swab_magic = swab64(UBERBLOCK_MAGIC); + struct zfs_uberblock *ub; + int swab_endian; + loff_t offset; + int tried; + int found; + + zdebug("probe_zfs\n"); + /* Look for at least 4 uberblocks to ensure a positive match */ + for (tried = found = 0, offset = VDEV_LABEL_UBERBLOCK; + tried < ZFS_TRIES && found < ZFS_WANT; + tried++, offset += 4096) { + /* also try the second uberblock copy */ + if (tried == (ZFS_TRIES / 2)) + offset = VDEV_LABEL_SIZE + VDEV_LABEL_UBERBLOCK; + + ub = (struct zfs_uberblock *) + blkid_probe_get_buffer(pr, offset, + sizeof(struct zfs_uberblock)); + if (ub == NULL) + return -1; + + if (ub->ub_magic == UBERBLOCK_MAGIC) + found++; + + if ((swab_endian = (ub->ub_magic == swab_magic))) + found++; + + zdebug("probe_zfs: found %s-endian uberblock at %llu\n", + swab_endian ? "big" : "little", offset >> 10); + } + + if (found < 4) + return -1; + + /* If we found the 4th uberblock, then we will have exited from the + * scanning loop immediately, and ub will be a valid uberblock. */ + blkid_probe_sprintf_version(pr, "%" PRIu64, swab_endian ? + swab64(ub->ub_version) : ub->ub_version); + + zfs_extract_guid_name(pr, offset); + + if (blkid_probe_set_magic(pr, offset, + sizeof(ub->ub_magic), + (unsigned char *) &ub->ub_magic)) + return -1; + + return 0; +} + +const struct blkid_idinfo zfs_idinfo = +{ + .name = "zfs_member", + .usage = BLKID_USAGE_RAID, + .probefunc = probe_zfs, + .minsz = 64 * 1024 * 1024, + .magics = BLKID_NONE_MAGIC +}; + -- cgit v1.2.3