/* xfs.c - XFS. */ /* * GRUB -- GRand Unified Bootloader * Copyright (C) 2005 Free Software Foundation, Inc. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ #include #include #include #include #include #include #include #include #define XFS_INODE_EXTENTS 9 #define XFS_INODE_FORMAT_INO 1 #define XFS_INODE_FORMAT_EXT 2 #define XFS_INODE_FORMAT_BTREE 3 struct grub_xfs_sblock { grub_uint8_t magic[4]; grub_uint32_t bsize; grub_uint8_t unused1[48]; grub_uint64_t rootino; grub_uint8_t unused2[20]; grub_uint32_t agsize; grub_uint8_t unused3[20]; grub_uint8_t label[12]; grub_uint8_t log2_bsize; grub_uint8_t unused4[2]; grub_uint8_t log2_inop; grub_uint8_t log2_agblk; } __attribute__ ((packed)); struct grub_xfs_dir_header { grub_uint8_t entries; grub_uint8_t smallino; grub_uint32_t parent; } __attribute__ ((packed)); struct grub_xfs_dir_entry { grub_uint8_t len; grub_uint16_t offset; char name[1]; /* Inode number follows, 32 bits. */ } __attribute__ ((packed)); struct grub_xfs_dir2_entry { grub_uint64_t inode; grub_uint8_t len; } __attribute__ ((packed)); typedef grub_uint32_t grub_xfs_extent[4]; struct grub_xfs_inode { grub_uint8_t magic[2]; grub_uint16_t mode; grub_uint8_t version; grub_uint8_t format; grub_uint8_t unused2[50]; grub_uint64_t size; grub_uint8_t unused3[36]; union { char raw[156]; struct dir { struct grub_xfs_dir_header dirhead; struct grub_xfs_dir_entry direntry[1]; } dir; grub_xfs_extent extents[XFS_INODE_EXTENTS]; } data __attribute__ ((packed)); } __attribute__ ((packed)); struct grub_xfs_dirblock_tail { grub_uint32_t leaf_count; grub_uint32_t leaf_stale; } __attribute__ ((packed)); struct grub_fshelp_node { struct grub_xfs_data *data; struct grub_xfs_inode inode; grub_uint64_t ino; int inode_read; }; struct grub_xfs_data { struct grub_xfs_sblock sblock; struct grub_xfs_inode *inode; grub_disk_t disk; int pos; int bsize; int agsize; struct grub_fshelp_node diropen; }; /* Filetype information as used in inodes. */ #define FILETYPE_INO_MASK 0170000 #define FILETYPE_INO_REG 0100000 #define FILETYPE_INO_DIRECTORY 0040000 #define FILETYPE_INO_SYMLINK 0120000 #define GRUB_XFS_INO_AGBITS(data) \ ((data)->sblock.log2_agblk + (data)->sblock.log2_inop) #define GRUB_XFS_INO_INOINAG(data, ino) \ (grub_be_to_cpu64 (ino) & ((1 << GRUB_XFS_INO_AGBITS (data)) - 1)) #define GRUB_XFS_INO_AG(data,ino) \ (grub_be_to_cpu64 (ino) >> GRUB_XFS_INO_AGBITS (data)) #define GRUB_XFS_EXTENT_OFFSET(inode,ex) \ ((grub_be_to_cpu32 ((inode)->data.extents[ex][0]) & ~(1 << 31)) << 23 \ | grub_be_to_cpu32 ((inode)->data.extents[ex][1]) >> 9) #define GRUB_XFS_EXTENT_BLOCK(inode,ex) \ ((grub_uint64_t) (grub_be_to_cpu32 ((inode)->data.extents[ex][1]) \ & (~255)) << 43 \ | (grub_uint64_t) grub_be_to_cpu32 ((inode)->data.extents[ex][2]) << 11 \ | grub_be_to_cpu32 ((inode)->data.extents[ex][3]) >> 21) #define GRUB_XFS_EXTENT_SIZE(inode,ex) \ (grub_be_to_cpu32 ((inode)->data.extents[ex][3]) & ((1 << 20) - 1)) #define GRUB_XFS_ROUND_TO_DIRENT(pos) ((((pos) + 8 - 1) / 8) * 8) #define GRUB_XFS_NEXT_DIRENT(pos,len) \ (pos) + GRUB_XFS_ROUND_TO_DIRENT (8 + 1 + len + 2) static inline int grub_xfs_inode_block (struct grub_xfs_data *data, grub_uint64_t ino) { long long int inoinag = GRUB_XFS_INO_INOINAG (data, ino); long long ag = GRUB_XFS_INO_AG (data, ino); long long block; block = (inoinag >> 4) + ag * data->agsize; block <<= (data->sblock.log2_bsize - GRUB_DISK_SECTOR_BITS); return block; } static inline int grub_xfs_inode_offset (struct grub_xfs_data *data, grub_uint64_t ino) { int inoag = GRUB_XFS_INO_INOINAG (data, ino); return (inoag & ((1 << 4) - 1)) << 8; } static grub_err_t grub_xfs_read_inode (struct grub_xfs_data *data, grub_uint64_t ino, struct grub_xfs_inode *inode) { int block = grub_xfs_inode_block (data, ino); int offset = grub_xfs_inode_offset (data, ino); /* Read the inode. */ if (grub_disk_read (data->disk, block, offset, sizeof (struct grub_xfs_inode), (char *) inode)) return grub_errno; if (grub_strncmp (inode->magic, "IN", 2)) return grub_error (GRUB_ERR_BAD_FS, "not a correct XFS inode.\n"); return 0; } static int grub_xfs_read_block (grub_fshelp_node_t node, int fileblock) { int ex; if (node->inode.format != XFS_INODE_FORMAT_EXT) { grub_error (GRUB_ERR_NOT_IMPLEMENTED_YET, "xfs does not support inode format %d yet", node->inode.format); return 0; } /* Iterate over each extent to figure out which extent has the block we are looking for. */ for (ex = 0; ex < XFS_INODE_EXTENTS; ex++) { grub_uint64_t start = GRUB_XFS_EXTENT_BLOCK (&node->inode, ex); int offset = GRUB_XFS_EXTENT_OFFSET (&node->inode, ex); int size = GRUB_XFS_EXTENT_SIZE (&node->inode, ex); unsigned int ag = start >> node->data->sblock.log2_agblk; unsigned int block = start & ((1 << node->data->sblock.log2_agblk) - 1); if (fileblock < offset + size) return (fileblock - offset + block) + ag * node->data->agsize; } grub_error (GRUB_ERR_FILE_READ_ERROR, "xfs block %d for inode %d is not in an extent.\n", fileblock, grub_be_to_cpu64 (node->ino)); return 0; } /* Read LEN bytes from the file described by DATA starting with byte POS. Return the amount of read bytes in READ. */ static grub_ssize_t grub_xfs_read_file (grub_fshelp_node_t node, void (*read_hook) (unsigned long sector, unsigned offset, unsigned length), int pos, unsigned int len, char *buf) { return grub_fshelp_read_file (node->data->disk, node, read_hook, pos, len, buf, grub_xfs_read_block, grub_be_to_cpu64 (node->inode.size), node->data->sblock.log2_bsize - GRUB_DISK_SECTOR_BITS); } static char * grub_xfs_read_symlink (grub_fshelp_node_t node) { int size = grub_be_to_cpu64 (node->inode.size); switch (node->inode.format) { case XFS_INODE_FORMAT_INO: return grub_strndup (node->inode.data.raw, size); case XFS_INODE_FORMAT_EXT: { char *symlink; grub_ssize_t numread; symlink = grub_malloc (size + 1); if (!symlink) return 0; numread = grub_xfs_read_file (node, 0, 0, size, symlink); if (numread != size) { grub_free (symlink); return 0; } symlink[size] = '\0'; return symlink; } } return 0; } static enum grub_fshelp_filetype grub_xfs_mode_to_filetype (grub_uint16_t mode) { if ((grub_be_to_cpu16 (mode) & FILETYPE_INO_MASK) == FILETYPE_INO_DIRECTORY) return GRUB_FSHELP_DIR; else if ((grub_be_to_cpu16 (mode) & FILETYPE_INO_MASK) == FILETYPE_INO_SYMLINK) return GRUB_FSHELP_SYMLINK; else if ((grub_be_to_cpu16 (mode) & FILETYPE_INO_MASK) == FILETYPE_INO_REG) return GRUB_FSHELP_REG; return GRUB_FSHELP_UNKNOWN; } static int grub_xfs_iterate_dir (grub_fshelp_node_t dir, int NESTED_FUNC_ATTR (*hook) (const char *filename, enum grub_fshelp_filetype filetype, grub_fshelp_node_t node)) { struct grub_fshelp_node *diro = (struct grub_fshelp_node *) dir; int call_hook (grub_uint64_t ino, char *filename) { struct grub_fshelp_node *fdiro; fdiro = grub_malloc (sizeof (struct grub_fshelp_node)); if (!fdiro) return 0; /* The inode should be read, otherwise the filetype can not be determined. */ fdiro->ino = ino; fdiro->inode_read = 1; fdiro->data = diro->data; grub_xfs_read_inode (diro->data, ino, &fdiro->inode); return hook (filename, grub_xfs_mode_to_filetype (fdiro->inode.mode), fdiro); } switch (diro->inode.format) { case XFS_INODE_FORMAT_INO: { struct grub_xfs_dir_entry *de = &diro->inode.data.dir.direntry[0]; int smallino = !diro->inode.data.dir.dirhead.smallino; int i; grub_uint64_t parent; /* If small inode numbers are used to pack the direntry, the parent inode number is small too. */ if (smallino) { parent = grub_be_to_cpu32 (diro->inode.data.dir.dirhead.parent); parent = grub_cpu_to_be64 (parent); } else { parent = *(grub_uint64_t *) &diro->inode.data.dir.dirhead.parent; /* The header is a bit bigger than usual. */ de = (struct grub_xfs_dir_entry *) ((char *) de + 4); } /* Synthesize the direntries for `.' and `..'. */ if (call_hook (diro->ino, ".")) return 1; if (call_hook (parent, "..")) return 1; for (i = 0; i < diro->inode.data.dir.dirhead.entries; i++) { grub_uint64_t ino; void *inopos = (((char *) de) + sizeof (struct grub_xfs_dir_entry) + de->len - 1); if (smallino) { ino = grub_be_to_cpu32 (*(grub_uint32_t *) inopos); ino = grub_cpu_to_be64 (ino); } else ino = *(grub_uint64_t *) inopos; if (call_hook (ino, de->name)) return 1; de = ((struct grub_xfs_dir_entry *) (((char *) de)+ sizeof (struct grub_xfs_dir_entry) + de->len + (smallino ? (sizeof (grub_uint32_t) : sizeof (grub_uint64_t))) - 1)); } break; } case XFS_INODE_FORMAT_BTREE: case XFS_INODE_FORMAT_EXT: { grub_ssize_t numread; char *dirblock; unsigned int blk; dirblock = grub_malloc (dir->data->bsize); if (!dirblock) return 0; /* Iterate over every block the directory has. */ for (blk = 0; blk < (grub_be_to_cpu64 (dir->inode.size) >> dir->data->sblock.log2_bsize); blk++) { /* The header is skipped, the first direntry is stored from byte 16. */ int pos = 16; int entries; int tail_start = (dir->data->bsize - sizeof (struct grub_xfs_dirblock_tail)); struct grub_xfs_dirblock_tail *tail; tail = (struct grub_xfs_dirblock_tail *) &dirblock[tail_start]; numread = grub_xfs_read_file (dir, 0, blk << dir->data->sblock.log2_bsize, dir->data->bsize, dirblock); entries = (grub_be_to_cpu32 (tail->leaf_count) - grub_be_to_cpu32 (tail->leaf_stale)); /* Iterate over all entries within this block. */ while (pos < (dir->data->bsize - (int) sizeof (struct grub_xfs_dir2_entry))) { struct grub_xfs_dir2_entry *direntry; grub_uint16_t *freetag; char *filename; direntry = (struct grub_xfs_dir2_entry *) &dirblock[pos]; freetag = (grub_uint16_t *) direntry; if (*freetag == 0XFFFF) { grub_uint16_t *skip = (grub_uint16_t *) (freetag + 1); /* This entry is not used, go to the next one. */ pos += grub_be_to_cpu16 (*skip); continue; } filename = &dirblock[pos + sizeof (*direntry)]; /* The byte after the filename is for the tag, which is not used by GRUB. So it can be overwritten. */ filename[direntry->len] = '\0'; if (call_hook (direntry->inode, filename)) { grub_free (dirblock); return 1; } /* Check if last direntry in this block is reached. */ entries--; if (!entries) break; /* Select the next directory entry. */ pos = GRUB_XFS_NEXT_DIRENT (pos, direntry->len); pos = GRUB_XFS_ROUND_TO_DIRENT (pos); } } grub_free (dirblock); break; } default: grub_error (GRUB_ERR_NOT_IMPLEMENTED_YET, "xfs does not support inode format %d yet", diro->inode.format); } return 0; } static struct grub_xfs_data * grub_xfs_mount (grub_disk_t disk) { struct grub_xfs_data *data = 0; data = grub_malloc (sizeof (struct grub_xfs_data)); if (!data) return 0; /* Read the superblock. */ if (grub_disk_read (disk, 0, 0, sizeof (struct grub_xfs_sblock), (char *) &data->sblock)) goto fail; if (grub_strncmp (data->sblock.magic, "XFSB", 4)) { grub_error (GRUB_ERR_BAD_FS, "not a xfs filesystem"); goto fail; } data->diropen.data = data; data->diropen.ino = data->sblock.rootino; data->diropen.inode_read = 1; data->bsize = grub_cpu_to_be32 (data->sblock.bsize); data->agsize = grub_cpu_to_be32 (data->sblock.agsize); data->disk = disk; data->inode = &data->diropen.inode; data->pos = 0; grub_xfs_read_inode (data, data->diropen.ino, data->inode); return data; fail: grub_free (data); return 0; } static grub_err_t grub_xfs_dir (grub_device_t device, const char *path, int (*hook) (const char *filename, int dir)) { struct grub_xfs_data *data = 0;; struct grub_fshelp_node *fdiro = 0; auto int NESTED_FUNC_ATTR iterate (const char *filename, enum grub_fshelp_filetype filetype, grub_fshelp_node_t node); int NESTED_FUNC_ATTR iterate (const char *filename, enum grub_fshelp_filetype filetype, grub_fshelp_node_t node) { grub_free (node); if (filetype == GRUB_FSHELP_DIR) return hook (filename, 1); else return hook (filename, 0); return 0; } #ifndef GRUB_UTIL grub_dl_ref (my_mod); #endif data = grub_xfs_mount (device->disk); if (!data) goto fail; grub_fshelp_find_file (path, &data->diropen, &fdiro, grub_xfs_iterate_dir, grub_xfs_read_symlink, GRUB_FSHELP_DIR); if (grub_errno) goto fail; grub_xfs_iterate_dir (fdiro, iterate); fail: if (fdiro != &data->diropen) grub_free (fdiro); grub_free (data); #ifndef GRUB_UTIL grub_dl_unref (my_mod); #endif return grub_errno; return 0; } /* Open a file named NAME and initialize FILE. */ static grub_err_t grub_xfs_open (struct grub_file *file, const char *name) { struct grub_xfs_data *data; struct grub_fshelp_node *fdiro = 0; #ifndef GRUB_UTIL grub_dl_ref (my_mod); #endif data = grub_xfs_mount (file->device->disk); if (!data) goto fail; grub_fshelp_find_file (name, &data->diropen, &fdiro, grub_xfs_iterate_dir, grub_xfs_read_symlink, GRUB_FSHELP_REG); if (grub_errno) goto fail; if (!fdiro->inode_read) { grub_xfs_read_inode (data, fdiro->ino, &fdiro->inode); if (grub_errno) goto fail; } grub_memcpy (data->inode, &fdiro->inode, sizeof (struct grub_xfs_inode)); grub_free (fdiro); file->size = grub_be_to_cpu64 (data->inode->size); file->data = data; file->offset = 0; return 0; fail: if (fdiro != &data->diropen) grub_free (fdiro); grub_free (data); #ifndef GRUB_UTIL grub_dl_unref (my_mod); #endif return grub_errno; } static grub_ssize_t grub_xfs_read (grub_file_t file, char *buf, grub_ssize_t len) { struct grub_xfs_data *data = (struct grub_xfs_data *) file->data; return grub_xfs_read_file (&data->diropen, file->read_hook, file->offset, len, buf); } static grub_err_t grub_xfs_close (grub_file_t file) { grub_free (file->data); #ifndef GRUB_UTIL grub_dl_unref (my_mod); #endif return GRUB_ERR_NONE; } static grub_err_t grub_xfs_label (grub_device_t device, char **label) { struct grub_xfs_data *data; grub_disk_t disk = device->disk; #ifndef GRUB_UTIL grub_dl_ref (my_mod); #endif data = grub_xfs_mount (disk); if (data) *label = grub_strndup (data->sblock.label, 12); else *label = 0; #ifndef GRUB_UTIL grub_dl_unref (my_mod); #endif grub_free (data); return grub_errno; } static struct grub_fs grub_xfs_fs = { .name = "xfs", .dir = grub_xfs_dir, .open = grub_xfs_open, .read = grub_xfs_read, .close = grub_xfs_close, .label = grub_xfs_label, .next = 0 }; #ifdef GRUB_UTIL void grub_xfs_init (void) { grub_fs_register (&grub_xfs_fs); } void grub_xfs_fini (void) { grub_fs_unregister (&grub_xfs_fs); } #else /* ! GRUB_UTIL */ GRUB_MOD_INIT { grub_fs_register (&grub_xfs_fs); my_mod = mod; } GRUB_MOD_FINI { grub_fs_unregister (&grub_xfs_fs); } #endif /* ! GRUB_UTIL */