diff options
author | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2016-03-26 05:33:09 -0300 |
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committer | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2016-03-26 05:33:09 -0300 |
commit | 4a327fcef90ba27150a3e8741441b68c605ae248 (patch) | |
tree | dedef84cccbd02054df4cfb844dd3c9d588edf83 /block/uuid.c | |
parent | a156245300d5362a3b4c4afdace9e2b90169fe43 (diff) |
Add TuxOnIce support adapted for the 4.5-gnu kernel versionpck-4.5-gnu
Diffstat (limited to 'block/uuid.c')
-rw-r--r-- | block/uuid.c | 509 |
1 files changed, 509 insertions, 0 deletions
diff --git a/block/uuid.c b/block/uuid.c new file mode 100644 index 000000000..4610d7b8f --- /dev/null +++ b/block/uuid.c @@ -0,0 +1,509 @@ +#include <linux/blkdev.h> +#include <linux/ctype.h> +#include <linux/fs_uuid.h> +#include <linux/slab.h> +#include <linux/export.h> + +static int debug_enabled; + +#define PRINTK(fmt, args...) do { \ + if (debug_enabled) \ + printk(KERN_DEBUG fmt, ## args); \ + } while(0) + +#define PRINT_HEX_DUMP(v1, v2, v3, v4, v5, v6, v7, v8) \ + do { \ + if (debug_enabled) \ + print_hex_dump(v1, v2, v3, v4, v5, v6, v7, v8); \ + } while(0) + +/* + * Simple UUID translation + */ + +struct uuid_info { + const char *key; + const char *name; + long bkoff; + unsigned sboff; + unsigned sig_len; + const char *magic; + int uuid_offset; + int last_mount_offset; + int last_mount_size; +}; + +/* + * Based on libuuid's blkid_magic array. Note that I don't + * have uuid offsets for all of these yet - mssing ones are 0x0. + * Further information welcome. + * + * Rearranged by page of fs signature for optimisation. + */ +static struct uuid_info uuid_list[] = { + { NULL, "oracleasm", 0, 32, 8, "ORCLDISK", 0x0, 0, 0 }, + { "ntfs", "ntfs", 0, 3, 8, "NTFS ", 0x0, 0, 0 }, + { "vfat", "vfat", 0, 0x52, 5, "MSWIN", 0x0, 0, 0 }, + { "vfat", "vfat", 0, 0x52, 8, "FAT32 ", 0x0, 0, 0 }, + { "vfat", "vfat", 0, 0x36, 5, "MSDOS", 0x0, 0, 0 }, + { "vfat", "vfat", 0, 0x36, 8, "FAT16 ", 0x0, 0, 0 }, + { "vfat", "vfat", 0, 0x36, 8, "FAT12 ", 0x0, 0, 0 }, + { "vfat", "vfat", 0, 0, 1, "\353", 0x0, 0, 0 }, + { "vfat", "vfat", 0, 0, 1, "\351", 0x0, 0, 0 }, + { "vfat", "vfat", 0, 0x1fe, 2, "\125\252", 0x0, 0, 0 }, + { "xfs", "xfs", 0, 0, 4, "XFSB", 0x20, 0, 0 }, + { "romfs", "romfs", 0, 0, 8, "-rom1fs-", 0x0, 0, 0 }, + { "bfs", "bfs", 0, 0, 4, "\316\372\173\033", 0, 0, 0 }, + { "cramfs", "cramfs", 0, 0, 4, "E=\315\050", 0x0, 0, 0 }, + { "qnx4", "qnx4", 0, 4, 6, "QNX4FS", 0, 0, 0 }, + { NULL, "crypt_LUKS", 0, 0, 6, "LUKS\xba\xbe", 0x0, 0, 0 }, + { "squashfs", "squashfs", 0, 0, 4, "sqsh", 0, 0, 0 }, + { "squashfs", "squashfs", 0, 0, 4, "hsqs", 0, 0, 0 }, + { "ocfs", "ocfs", 0, 8, 9, "OracleCFS", 0x0, 0, 0 }, + { "lvm2pv", "lvm2pv", 0, 0x018, 8, "LVM2 001", 0x0, 0, 0 }, + { "sysv", "sysv", 0, 0x3f8, 4, "\020~\030\375", 0, 0, 0 }, + { "ext", "ext", 1, 0x38, 2, "\123\357", 0x468, 0x42c, 4 }, + { "minix", "minix", 1, 0x10, 2, "\177\023", 0, 0, 0 }, + { "minix", "minix", 1, 0x10, 2, "\217\023", 0, 0, 0 }, + { "minix", "minix", 1, 0x10, 2, "\150\044", 0, 0, 0 }, + { "minix", "minix", 1, 0x10, 2, "\170\044", 0, 0, 0 }, + { "lvm2pv", "lvm2pv", 1, 0x018, 8, "LVM2 001", 0x0, 0, 0 }, + { "vxfs", "vxfs", 1, 0, 4, "\365\374\001\245", 0, 0, 0 }, + { "hfsplus", "hfsplus", 1, 0, 2, "BD", 0x0, 0, 0 }, + { "hfsplus", "hfsplus", 1, 0, 2, "H+", 0x0, 0, 0 }, + { "hfsplus", "hfsplus", 1, 0, 2, "HX", 0x0, 0, 0 }, + { "hfs", "hfs", 1, 0, 2, "BD", 0x0, 0, 0 }, + { "ocfs2", "ocfs2", 1, 0, 6, "OCFSV2", 0x0, 0, 0 }, + { "lvm2pv", "lvm2pv", 0, 0x218, 8, "LVM2 001", 0x0, 0, 0 }, + { "lvm2pv", "lvm2pv", 1, 0x218, 8, "LVM2 001", 0x0, 0, 0 }, + { "ocfs2", "ocfs2", 2, 0, 6, "OCFSV2", 0x0, 0, 0 }, + { "swap", "swap", 0, 0xff6, 10, "SWAP-SPACE", 0x40c, 0, 0 }, + { "swap", "swap", 0, 0xff6, 10, "SWAPSPACE2", 0x40c, 0, 0 }, + { "swap", "swsuspend", 0, 0xff6, 9, "S1SUSPEND", 0x40c, 0, 0 }, + { "swap", "swsuspend", 0, 0xff6, 9, "S2SUSPEND", 0x40c, 0, 0 }, + { "swap", "swsuspend", 0, 0xff6, 9, "ULSUSPEND", 0x40c, 0, 0 }, + { "ocfs2", "ocfs2", 4, 0, 6, "OCFSV2", 0x0, 0, 0 }, + { "ocfs2", "ocfs2", 8, 0, 6, "OCFSV2", 0x0, 0, 0 }, + { "hpfs", "hpfs", 8, 0, 4, "I\350\225\371", 0, 0, 0 }, + { "reiserfs", "reiserfs", 8, 0x34, 8, "ReIsErFs", 0x10054, 0, 0 }, + { "reiserfs", "reiserfs", 8, 20, 8, "ReIsErFs", 0x10054, 0, 0 }, + { "zfs", "zfs", 8, 0, 8, "\0\0\x02\xf5\xb0\x07\xb1\x0c", 0x0, 0, 0 }, + { "zfs", "zfs", 8, 0, 8, "\x0c\xb1\x07\xb0\xf5\x02\0\0", 0x0, 0, 0 }, + { "ufs", "ufs", 8, 0x55c, 4, "T\031\001\000", 0, 0, 0 }, + { "swap", "swap", 0, 0x1ff6, 10, "SWAP-SPACE", 0x40c, 0, 0 }, + { "swap", "swap", 0, 0x1ff6, 10, "SWAPSPACE2", 0x40c, 0, 0 }, + { "swap", "swsuspend", 0, 0x1ff6, 9, "S1SUSPEND", 0x40c, 0, 0 }, + { "swap", "swsuspend", 0, 0x1ff6, 9, "S2SUSPEND", 0x40c, 0, 0 }, + { "swap", "swsuspend", 0, 0x1ff6, 9, "ULSUSPEND", 0x40c, 0, 0 }, + { "reiserfs", "reiserfs", 64, 0x34, 9, "ReIsEr2Fs", 0x10054, 0, 0 }, + { "reiserfs", "reiserfs", 64, 0x34, 9, "ReIsEr3Fs", 0x10054, 0, 0 }, + { "reiserfs", "reiserfs", 64, 0x34, 8, "ReIsErFs", 0x10054, 0, 0 }, + { "reiser4", "reiser4", 64, 0, 7, "ReIsEr4", 0x100544, 0, 0 }, + { "gfs2", "gfs2", 64, 0, 4, "\x01\x16\x19\x70", 0x0, 0, 0 }, + { "gfs", "gfs", 64, 0, 4, "\x01\x16\x19\x70", 0x0, 0, 0 }, + { "btrfs", "btrfs", 64, 0x40, 8, "_BHRfS_M", 0x0, 0, 0 }, + { "swap", "swap", 0, 0x3ff6, 10, "SWAP-SPACE", 0x40c, 0, 0 }, + { "swap", "swap", 0, 0x3ff6, 10, "SWAPSPACE2", 0x40c, 0, 0 }, + { "swap", "swsuspend", 0, 0x3ff6, 9, "S1SUSPEND", 0x40c, 0, 0 }, + { "swap", "swsuspend", 0, 0x3ff6, 9, "S2SUSPEND", 0x40c, 0, 0 }, + { "swap", "swsuspend", 0, 0x3ff6, 9, "ULSUSPEND", 0x40c, 0, 0 }, + { "udf", "udf", 32, 1, 5, "BEA01", 0x0, 0, 0 }, + { "udf", "udf", 32, 1, 5, "BOOT2", 0x0, 0, 0 }, + { "udf", "udf", 32, 1, 5, "CD001", 0x0, 0, 0 }, + { "udf", "udf", 32, 1, 5, "CDW02", 0x0, 0, 0 }, + { "udf", "udf", 32, 1, 5, "NSR02", 0x0, 0, 0 }, + { "udf", "udf", 32, 1, 5, "NSR03", 0x0, 0, 0 }, + { "udf", "udf", 32, 1, 5, "TEA01", 0x0, 0, 0 }, + { "iso9660", "iso9660", 32, 1, 5, "CD001", 0x0, 0, 0 }, + { "iso9660", "iso9660", 32, 9, 5, "CDROM", 0x0, 0, 0 }, + { "jfs", "jfs", 32, 0, 4, "JFS1", 0x88, 0, 0 }, + { "swap", "swap", 0, 0x7ff6, 10, "SWAP-SPACE", 0x40c, 0, 0 }, + { "swap", "swap", 0, 0x7ff6, 10, "SWAPSPACE2", 0x40c, 0, 0 }, + { "swap", "swsuspend", 0, 0x7ff6, 9, "S1SUSPEND", 0x40c, 0, 0 }, + { "swap", "swsuspend", 0, 0x7ff6, 9, "S2SUSPEND", 0x40c, 0, 0 }, + { "swap", "swsuspend", 0, 0x7ff6, 9, "ULSUSPEND", 0x40c, 0, 0 }, + { "swap", "swap", 0, 0xfff6, 10, "SWAP-SPACE", 0x40c, 0, 0 }, + { "swap", "swap", 0, 0xfff6, 10, "SWAPSPACE2", 0x40c, 0, 0 }, + { "swap", "swsuspend", 0, 0xfff6, 9, "S1SUSPEND", 0x40c, 0, 0 }, + { "swap", "swsuspend", 0, 0xfff6, 9, "S2SUSPEND", 0x40c, 0, 0 }, + { "swap", "swsuspend", 0, 0xfff6, 9, "ULSUSPEND", 0x40c, 0, 0 }, + { "zfs", "zfs", 264, 0, 8, "\0\0\x02\xf5\xb0\x07\xb1\x0c", 0x0, 0, 0 }, + { "zfs", "zfs", 264, 0, 8, "\x0c\xb1\x07\xb0\xf5\x02\0\0", 0x0, 0, 0 }, + { NULL, NULL, 0, 0, 0, NULL, 0x0, 0, 0 } +}; + +static int null_uuid(const char *uuid) +{ + int i; + + for (i = 0; i < 16 && !uuid[i]; i++); + + return (i == 16); +} + + +static void uuid_end_bio(struct bio *bio) +{ + struct page *page = bio->bi_io_vec[0].bv_page; + + if (bio->bi_error) + SetPageError(page); + + unlock_page(page); + bio_put(bio); +} + + +/** + * submit - submit BIO request + * @dev: The block device we're using. + * @page_num: The page we're reading. + * + * Based on Patrick Mochell's pmdisk code from long ago: "Straight from the + * textbook - allocate and initialize the bio. If we're writing, make sure + * the page is marked as dirty. Then submit it and carry on." + **/ +static struct page *read_bdev_page(struct block_device *dev, int page_num) +{ + struct bio *bio = NULL; + struct page *page = alloc_page(GFP_NOFS | __GFP_HIGHMEM); + + if (!page) { + printk(KERN_ERR "Failed to allocate a page for reading data " + "in UUID checks."); + return NULL; + } + + bio = bio_alloc(GFP_NOFS, 1); + bio->bi_bdev = dev; + bio->bi_iter.bi_sector = page_num << 3; + bio->bi_end_io = uuid_end_bio; + bio->bi_flags |= (1 << BIO_TOI); + + PRINTK("Submitting bio on device %lx, page %d using bio %p and page %p.\n", + (unsigned long) dev->bd_dev, page_num, bio, page); + + if (bio_add_page(bio, page, PAGE_SIZE, 0) < PAGE_SIZE) { + printk(KERN_DEBUG "ERROR: adding page to bio at %d\n", + page_num); + bio_put(bio); + __free_page(page); + printk(KERN_DEBUG "read_bdev_page freed page %p (in error " + "path).\n", page); + return NULL; + } + + lock_page(page); + submit_bio(READ | REQ_SYNC, bio); + + wait_on_page_locked(page); + if (PageError(page)) { + __free_page(page); + page = NULL; + } + return page; +} + +int bdev_matches_key(struct block_device *bdev, const char *key) +{ + unsigned char *data = NULL; + struct page *data_page = NULL; + + int dev_offset, pg_num, pg_off, i; + int last_pg_num = -1; + int result = 0; + char buf[50]; + + if (null_uuid(key)) { + PRINTK("Refusing to find a NULL key.\n"); + return 0; + } + + if (!bdev->bd_disk) { + bdevname(bdev, buf); + PRINTK("bdev %s has no bd_disk.\n", buf); + return 0; + } + + if (!bdev->bd_disk->queue) { + bdevname(bdev, buf); + PRINTK("bdev %s has no queue.\n", buf); + return 0; + } + + for (i = 0; uuid_list[i].name; i++) { + struct uuid_info *dat = &uuid_list[i]; + + if (!dat->key || strcmp(dat->key, key)) + continue; + + dev_offset = (dat->bkoff << 10) + dat->sboff; + pg_num = dev_offset >> 12; + pg_off = dev_offset & 0xfff; + + if ((((pg_num + 1) << 3) - 1) > bdev->bd_part->nr_sects >> 1) + continue; + + if (pg_num != last_pg_num) { + if (data_page) { + kunmap(data_page); + __free_page(data_page); + } + data_page = read_bdev_page(bdev, pg_num); + if (!data_page) + continue; + data = kmap(data_page); + } + + last_pg_num = pg_num; + + if (strncmp(&data[pg_off], dat->magic, dat->sig_len)) + continue; + + result = 1; + break; + } + + if (data_page) { + kunmap(data_page); + __free_page(data_page); + } + + return result; +} + +/* + * part_matches_fs_info - Does the given partition match the details given? + * + * Returns a score saying how good the match is. + * 0 = no UUID match. + * 1 = UUID but last mount time differs. + * 2 = UUID, last mount time but not dev_t + * 3 = perfect match + * + * This lets us cope elegantly with probing resulting in dev_ts changing + * from boot to boot, and with the case where a user copies a partition + * (UUID is non unique), and we need to check the last mount time of the + * correct partition. + */ +int part_matches_fs_info(struct hd_struct *part, struct fs_info *seek) +{ + struct block_device *bdev; + struct fs_info *got; + int result = 0; + char buf[50]; + + if (null_uuid((char *) &seek->uuid)) { + PRINTK("Refusing to find a NULL uuid.\n"); + return 0; + } + + bdev = bdget(part_devt(part)); + + PRINTK("part_matches fs info considering %x.\n", part_devt(part)); + + if (blkdev_get(bdev, FMODE_READ, 0)) { + PRINTK("blkdev_get failed.\n"); + return 0; + } + + if (!bdev->bd_disk) { + bdevname(bdev, buf); + PRINTK("bdev %s has no bd_disk.\n", buf); + goto out; + } + + if (!bdev->bd_disk->queue) { + bdevname(bdev, buf); + PRINTK("bdev %s has no queue.\n", buf); + goto out; + } + + got = fs_info_from_block_dev(bdev); + + if (got && !memcmp(got->uuid, seek->uuid, 16)) { + PRINTK(" Have matching UUID.\n"); + PRINTK(" Got: LMS %d, LM %p.\n", got->last_mount_size, got->last_mount); + PRINTK(" Seek: LMS %d, LM %p.\n", seek->last_mount_size, seek->last_mount); + result = 1; + + if (got->last_mount_size == seek->last_mount_size && + got->last_mount && seek->last_mount && + !memcmp(got->last_mount, seek->last_mount, + got->last_mount_size)) { + result = 2; + + PRINTK(" Matching last mount time.\n"); + + if (part_devt(part) == seek->dev_t) { + result = 3; + PRINTK(" Matching dev_t.\n"); + } else + PRINTK("Dev_ts differ (%x vs %x).\n", part_devt(part), seek->dev_t); + } + } + + PRINTK(" Score for %x is %d.\n", part_devt(part), result); + free_fs_info(got); +out: + blkdev_put(bdev, FMODE_READ); + return result; +} + +void free_fs_info(struct fs_info *fs_info) +{ + if (!fs_info || IS_ERR(fs_info)) + return; + + if (fs_info->last_mount) + kfree(fs_info->last_mount); + + kfree(fs_info); +} + +struct fs_info *fs_info_from_block_dev(struct block_device *bdev) +{ + unsigned char *data = NULL; + struct page *data_page = NULL; + + int dev_offset, pg_num, pg_off; + int uuid_pg_num, uuid_pg_off, i; + unsigned char *uuid_data = NULL; + struct page *uuid_data_page = NULL; + + int last_pg_num = -1, last_uuid_pg_num = 0; + char buf[50]; + struct fs_info *fs_info = NULL; + + bdevname(bdev, buf); + + PRINTK("uuid_from_block_dev looking for partition type of %s.\n", buf); + + for (i = 0; uuid_list[i].name; i++) { + struct uuid_info *dat = &uuid_list[i]; + dev_offset = (dat->bkoff << 10) + dat->sboff; + pg_num = dev_offset >> 12; + pg_off = dev_offset & 0xfff; + uuid_pg_num = dat->uuid_offset >> 12; + uuid_pg_off = dat->uuid_offset & 0xfff; + + if ((((pg_num + 1) << 3) - 1) > bdev->bd_part->nr_sects >> 1) + continue; + + /* Ignore partition types with no UUID offset */ + if (!dat->uuid_offset) + continue; + + if (pg_num != last_pg_num) { + if (data_page) { + kunmap(data_page); + __free_page(data_page); + } + data_page = read_bdev_page(bdev, pg_num); + if (!data_page) + continue; + data = kmap(data_page); + } + + last_pg_num = pg_num; + + if (strncmp(&data[pg_off], dat->magic, dat->sig_len)) + continue; + + PRINTK("This partition looks like %s.\n", dat->name); + + fs_info = kzalloc(sizeof(struct fs_info), GFP_KERNEL); + + if (!fs_info) { + PRINTK("Failed to allocate fs_info struct."); + fs_info = ERR_PTR(-ENOMEM); + break; + } + + /* UUID can't be off the end of the disk */ + if ((uuid_pg_num > bdev->bd_part->nr_sects >> 3) || + !dat->uuid_offset) + goto no_uuid; + + if (!uuid_data || uuid_pg_num != last_uuid_pg_num) { + /* No need to reread the page from above */ + if (uuid_pg_num == pg_num && uuid_data) + memcpy(uuid_data, data, PAGE_SIZE); + else { + if (uuid_data_page) { + kunmap(uuid_data_page); + __free_page(uuid_data_page); + } + uuid_data_page = read_bdev_page(bdev, uuid_pg_num); + if (!uuid_data_page) + continue; + uuid_data = kmap(uuid_data_page); + } + } + + last_uuid_pg_num = uuid_pg_num; + memcpy(&fs_info->uuid, &uuid_data[uuid_pg_off], 16); + fs_info->dev_t = bdev->bd_dev; + +no_uuid: + PRINT_HEX_DUMP(KERN_EMERG, "fs_info_from_block_dev " + "returning uuid ", DUMP_PREFIX_NONE, 16, 1, + fs_info->uuid, 16, 0); + + if (dat->last_mount_size) { + int pg = dat->last_mount_offset >> 12, sz; + int off = dat->last_mount_offset & 0xfff; + struct page *last_mount = read_bdev_page(bdev, pg); + unsigned char *last_mount_data; + char *ptr; + + if (!last_mount) { + fs_info = ERR_PTR(-ENOMEM); + break; + } + last_mount_data = kmap(last_mount); + sz = dat->last_mount_size; + ptr = kmalloc(sz, GFP_KERNEL); + + if (!ptr) { + printk(KERN_EMERG "fs_info_from_block_dev " + "failed to get memory for last mount " + "timestamp."); + free_fs_info(fs_info); + fs_info = ERR_PTR(-ENOMEM); + } else { + fs_info->last_mount = ptr; + fs_info->last_mount_size = sz; + memcpy(ptr, &last_mount_data[off], sz); + } + + kunmap(last_mount); + __free_page(last_mount); + } + break; + } + + if (data_page) { + kunmap(data_page); + __free_page(data_page); + } + + if (uuid_data_page) { + kunmap(uuid_data_page); + __free_page(uuid_data_page); + } + + return fs_info; +} + +static int __init uuid_debug_setup(char *str) +{ + int value; + + if (sscanf(str, "=%d", &value)) + debug_enabled = value; + + return 1; +} + +__setup("uuid_debug", uuid_debug_setup); |