diff options
Diffstat (limited to 'fs/qnx6/inode.c')
-rw-r--r-- | fs/qnx6/inode.c | 685 |
1 files changed, 685 insertions, 0 deletions
diff --git a/fs/qnx6/inode.c b/fs/qnx6/inode.c new file mode 100644 index 000000000..32d2e1a97 --- /dev/null +++ b/fs/qnx6/inode.c @@ -0,0 +1,685 @@ +/* + * QNX6 file system, Linux implementation. + * + * Version : 1.0.0 + * + * History : + * + * 01-02-2012 by Kai Bankett (chaosman@ontika.net) : first release. + * 16-02-2012 pagemap extension by Al Viro + * + */ + +#include <linux/module.h> +#include <linux/init.h> +#include <linux/slab.h> +#include <linux/highuid.h> +#include <linux/pagemap.h> +#include <linux/buffer_head.h> +#include <linux/writeback.h> +#include <linux/statfs.h> +#include <linux/parser.h> +#include <linux/seq_file.h> +#include <linux/mount.h> +#include <linux/crc32.h> +#include <linux/mpage.h> +#include "qnx6.h" + +static const struct super_operations qnx6_sops; + +static void qnx6_put_super(struct super_block *sb); +static struct inode *qnx6_alloc_inode(struct super_block *sb); +static void qnx6_destroy_inode(struct inode *inode); +static int qnx6_remount(struct super_block *sb, int *flags, char *data); +static int qnx6_statfs(struct dentry *dentry, struct kstatfs *buf); +static int qnx6_show_options(struct seq_file *seq, struct dentry *root); + +static const struct super_operations qnx6_sops = { + .alloc_inode = qnx6_alloc_inode, + .destroy_inode = qnx6_destroy_inode, + .put_super = qnx6_put_super, + .statfs = qnx6_statfs, + .remount_fs = qnx6_remount, + .show_options = qnx6_show_options, +}; + +static int qnx6_show_options(struct seq_file *seq, struct dentry *root) +{ + struct super_block *sb = root->d_sb; + struct qnx6_sb_info *sbi = QNX6_SB(sb); + + if (sbi->s_mount_opt & QNX6_MOUNT_MMI_FS) + seq_puts(seq, ",mmi_fs"); + return 0; +} + +static int qnx6_remount(struct super_block *sb, int *flags, char *data) +{ + sync_filesystem(sb); + *flags |= MS_RDONLY; + return 0; +} + +static unsigned qnx6_get_devblock(struct super_block *sb, __fs32 block) +{ + struct qnx6_sb_info *sbi = QNX6_SB(sb); + return fs32_to_cpu(sbi, block) + sbi->s_blks_off; +} + +static unsigned qnx6_block_map(struct inode *inode, unsigned iblock); + +static int qnx6_get_block(struct inode *inode, sector_t iblock, + struct buffer_head *bh, int create) +{ + unsigned phys; + + pr_debug("qnx6_get_block inode=[%ld] iblock=[%ld]\n", + inode->i_ino, (unsigned long)iblock); + + phys = qnx6_block_map(inode, iblock); + if (phys) { + /* logical block is before EOF */ + map_bh(bh, inode->i_sb, phys); + } + return 0; +} + +static int qnx6_check_blockptr(__fs32 ptr) +{ + if (ptr == ~(__fs32)0) { + pr_err("hit unused blockpointer.\n"); + return 0; + } + return 1; +} + +static int qnx6_readpage(struct file *file, struct page *page) +{ + return mpage_readpage(page, qnx6_get_block); +} + +static int qnx6_readpages(struct file *file, struct address_space *mapping, + struct list_head *pages, unsigned nr_pages) +{ + return mpage_readpages(mapping, pages, nr_pages, qnx6_get_block); +} + +/* + * returns the block number for the no-th element in the tree + * inodebits requred as there are multiple inodes in one inode block + */ +static unsigned qnx6_block_map(struct inode *inode, unsigned no) +{ + struct super_block *s = inode->i_sb; + struct qnx6_sb_info *sbi = QNX6_SB(s); + struct qnx6_inode_info *ei = QNX6_I(inode); + unsigned block = 0; + struct buffer_head *bh; + __fs32 ptr; + int levelptr; + int ptrbits = sbi->s_ptrbits; + int bitdelta; + u32 mask = (1 << ptrbits) - 1; + int depth = ei->di_filelevels; + int i; + + bitdelta = ptrbits * depth; + levelptr = no >> bitdelta; + + if (levelptr > QNX6_NO_DIRECT_POINTERS - 1) { + pr_err("Requested file block number (%u) too big.", no); + return 0; + } + + block = qnx6_get_devblock(s, ei->di_block_ptr[levelptr]); + + for (i = 0; i < depth; i++) { + bh = sb_bread(s, block); + if (!bh) { + pr_err("Error reading block (%u)\n", block); + return 0; + } + bitdelta -= ptrbits; + levelptr = (no >> bitdelta) & mask; + ptr = ((__fs32 *)bh->b_data)[levelptr]; + + if (!qnx6_check_blockptr(ptr)) + return 0; + + block = qnx6_get_devblock(s, ptr); + brelse(bh); + } + return block; +} + +static int qnx6_statfs(struct dentry *dentry, struct kstatfs *buf) +{ + struct super_block *sb = dentry->d_sb; + struct qnx6_sb_info *sbi = QNX6_SB(sb); + u64 id = huge_encode_dev(sb->s_bdev->bd_dev); + + buf->f_type = sb->s_magic; + buf->f_bsize = sb->s_blocksize; + buf->f_blocks = fs32_to_cpu(sbi, sbi->sb->sb_num_blocks); + buf->f_bfree = fs32_to_cpu(sbi, sbi->sb->sb_free_blocks); + buf->f_files = fs32_to_cpu(sbi, sbi->sb->sb_num_inodes); + buf->f_ffree = fs32_to_cpu(sbi, sbi->sb->sb_free_inodes); + buf->f_bavail = buf->f_bfree; + buf->f_namelen = QNX6_LONG_NAME_MAX; + buf->f_fsid.val[0] = (u32)id; + buf->f_fsid.val[1] = (u32)(id >> 32); + + return 0; +} + +/* + * Check the root directory of the filesystem to make sure + * it really _is_ a qnx6 filesystem, and to check the size + * of the directory entry. + */ +static const char *qnx6_checkroot(struct super_block *s) +{ + static char match_root[2][3] = {".\0\0", "..\0"}; + int i, error = 0; + struct qnx6_dir_entry *dir_entry; + struct inode *root = d_inode(s->s_root); + struct address_space *mapping = root->i_mapping; + struct page *page = read_mapping_page(mapping, 0, NULL); + if (IS_ERR(page)) + return "error reading root directory"; + kmap(page); + dir_entry = page_address(page); + for (i = 0; i < 2; i++) { + /* maximum 3 bytes - due to match_root limitation */ + if (strncmp(dir_entry[i].de_fname, match_root[i], 3)) + error = 1; + } + qnx6_put_page(page); + if (error) + return "error reading root directory."; + return NULL; +} + +#ifdef CONFIG_QNX6FS_DEBUG +void qnx6_superblock_debug(struct qnx6_super_block *sb, struct super_block *s) +{ + struct qnx6_sb_info *sbi = QNX6_SB(s); + + pr_debug("magic: %08x\n", fs32_to_cpu(sbi, sb->sb_magic)); + pr_debug("checksum: %08x\n", fs32_to_cpu(sbi, sb->sb_checksum)); + pr_debug("serial: %llx\n", fs64_to_cpu(sbi, sb->sb_serial)); + pr_debug("flags: %08x\n", fs32_to_cpu(sbi, sb->sb_flags)); + pr_debug("blocksize: %08x\n", fs32_to_cpu(sbi, sb->sb_blocksize)); + pr_debug("num_inodes: %08x\n", fs32_to_cpu(sbi, sb->sb_num_inodes)); + pr_debug("free_inodes: %08x\n", fs32_to_cpu(sbi, sb->sb_free_inodes)); + pr_debug("num_blocks: %08x\n", fs32_to_cpu(sbi, sb->sb_num_blocks)); + pr_debug("free_blocks: %08x\n", fs32_to_cpu(sbi, sb->sb_free_blocks)); + pr_debug("inode_levels: %02x\n", sb->Inode.levels); +} +#endif + +enum { + Opt_mmifs, + Opt_err +}; + +static const match_table_t tokens = { + {Opt_mmifs, "mmi_fs"}, + {Opt_err, NULL} +}; + +static int qnx6_parse_options(char *options, struct super_block *sb) +{ + char *p; + struct qnx6_sb_info *sbi = QNX6_SB(sb); + substring_t args[MAX_OPT_ARGS]; + + if (!options) + return 1; + + while ((p = strsep(&options, ",")) != NULL) { + int token; + if (!*p) + continue; + + token = match_token(p, tokens, args); + switch (token) { + case Opt_mmifs: + set_opt(sbi->s_mount_opt, MMI_FS); + break; + default: + return 0; + } + } + return 1; +} + +static struct buffer_head *qnx6_check_first_superblock(struct super_block *s, + int offset, int silent) +{ + struct qnx6_sb_info *sbi = QNX6_SB(s); + struct buffer_head *bh; + struct qnx6_super_block *sb; + + /* Check the superblock signatures + start with the first superblock */ + bh = sb_bread(s, offset); + if (!bh) { + pr_err("unable to read the first superblock\n"); + return NULL; + } + sb = (struct qnx6_super_block *)bh->b_data; + if (fs32_to_cpu(sbi, sb->sb_magic) != QNX6_SUPER_MAGIC) { + sbi->s_bytesex = BYTESEX_BE; + if (fs32_to_cpu(sbi, sb->sb_magic) == QNX6_SUPER_MAGIC) { + /* we got a big endian fs */ + pr_debug("fs got different endianness.\n"); + return bh; + } else + sbi->s_bytesex = BYTESEX_LE; + if (!silent) { + if (offset == 0) { + pr_err("wrong signature (magic) in superblock #1.\n"); + } else { + pr_info("wrong signature (magic) at position (0x%lx) - will try alternative position (0x0000).\n", + offset * s->s_blocksize); + } + } + brelse(bh); + return NULL; + } + return bh; +} + +static struct inode *qnx6_private_inode(struct super_block *s, + struct qnx6_root_node *p); + +static int qnx6_fill_super(struct super_block *s, void *data, int silent) +{ + struct buffer_head *bh1 = NULL, *bh2 = NULL; + struct qnx6_super_block *sb1 = NULL, *sb2 = NULL; + struct qnx6_sb_info *sbi; + struct inode *root; + const char *errmsg; + struct qnx6_sb_info *qs; + int ret = -EINVAL; + u64 offset; + int bootblock_offset = QNX6_BOOTBLOCK_SIZE; + + qs = kzalloc(sizeof(struct qnx6_sb_info), GFP_KERNEL); + if (!qs) + return -ENOMEM; + s->s_fs_info = qs; + + /* Superblock always is 512 Byte long */ + if (!sb_set_blocksize(s, QNX6_SUPERBLOCK_SIZE)) { + pr_err("unable to set blocksize\n"); + goto outnobh; + } + + /* parse the mount-options */ + if (!qnx6_parse_options((char *) data, s)) { + pr_err("invalid mount options.\n"); + goto outnobh; + } + if (test_opt(s, MMI_FS)) { + sb1 = qnx6_mmi_fill_super(s, silent); + if (sb1) + goto mmi_success; + else + goto outnobh; + } + sbi = QNX6_SB(s); + sbi->s_bytesex = BYTESEX_LE; + /* Check the superblock signatures + start with the first superblock */ + bh1 = qnx6_check_first_superblock(s, + bootblock_offset / QNX6_SUPERBLOCK_SIZE, silent); + if (!bh1) { + /* try again without bootblock offset */ + bh1 = qnx6_check_first_superblock(s, 0, silent); + if (!bh1) { + pr_err("unable to read the first superblock\n"); + goto outnobh; + } + /* seems that no bootblock at partition start */ + bootblock_offset = 0; + } + sb1 = (struct qnx6_super_block *)bh1->b_data; + +#ifdef CONFIG_QNX6FS_DEBUG + qnx6_superblock_debug(sb1, s); +#endif + + /* checksum check - start at byte 8 and end at byte 512 */ + if (fs32_to_cpu(sbi, sb1->sb_checksum) != + crc32_be(0, (char *)(bh1->b_data + 8), 504)) { + pr_err("superblock #1 checksum error\n"); + goto out; + } + + /* set new blocksize */ + if (!sb_set_blocksize(s, fs32_to_cpu(sbi, sb1->sb_blocksize))) { + pr_err("unable to set blocksize\n"); + goto out; + } + /* blocksize invalidates bh - pull it back in */ + brelse(bh1); + bh1 = sb_bread(s, bootblock_offset >> s->s_blocksize_bits); + if (!bh1) + goto outnobh; + sb1 = (struct qnx6_super_block *)bh1->b_data; + + /* calculate second superblock blocknumber */ + offset = fs32_to_cpu(sbi, sb1->sb_num_blocks) + + (bootblock_offset >> s->s_blocksize_bits) + + (QNX6_SUPERBLOCK_AREA >> s->s_blocksize_bits); + + /* set bootblock offset */ + sbi->s_blks_off = (bootblock_offset >> s->s_blocksize_bits) + + (QNX6_SUPERBLOCK_AREA >> s->s_blocksize_bits); + + /* next the second superblock */ + bh2 = sb_bread(s, offset); + if (!bh2) { + pr_err("unable to read the second superblock\n"); + goto out; + } + sb2 = (struct qnx6_super_block *)bh2->b_data; + if (fs32_to_cpu(sbi, sb2->sb_magic) != QNX6_SUPER_MAGIC) { + if (!silent) + pr_err("wrong signature (magic) in superblock #2.\n"); + goto out; + } + + /* checksum check - start at byte 8 and end at byte 512 */ + if (fs32_to_cpu(sbi, sb2->sb_checksum) != + crc32_be(0, (char *)(bh2->b_data + 8), 504)) { + pr_err("superblock #2 checksum error\n"); + goto out; + } + + if (fs64_to_cpu(sbi, sb1->sb_serial) >= + fs64_to_cpu(sbi, sb2->sb_serial)) { + /* superblock #1 active */ + sbi->sb_buf = bh1; + sbi->sb = (struct qnx6_super_block *)bh1->b_data; + brelse(bh2); + pr_info("superblock #1 active\n"); + } else { + /* superblock #2 active */ + sbi->sb_buf = bh2; + sbi->sb = (struct qnx6_super_block *)bh2->b_data; + brelse(bh1); + pr_info("superblock #2 active\n"); + } +mmi_success: + /* sanity check - limit maximum indirect pointer levels */ + if (sb1->Inode.levels > QNX6_PTR_MAX_LEVELS) { + pr_err("too many inode levels (max %i, sb %i)\n", + QNX6_PTR_MAX_LEVELS, sb1->Inode.levels); + goto out; + } + if (sb1->Longfile.levels > QNX6_PTR_MAX_LEVELS) { + pr_err("too many longfilename levels (max %i, sb %i)\n", + QNX6_PTR_MAX_LEVELS, sb1->Longfile.levels); + goto out; + } + s->s_op = &qnx6_sops; + s->s_magic = QNX6_SUPER_MAGIC; + s->s_flags |= MS_RDONLY; /* Yup, read-only yet */ + + /* ease the later tree level calculations */ + sbi = QNX6_SB(s); + sbi->s_ptrbits = ilog2(s->s_blocksize / 4); + sbi->inodes = qnx6_private_inode(s, &sb1->Inode); + if (!sbi->inodes) + goto out; + sbi->longfile = qnx6_private_inode(s, &sb1->Longfile); + if (!sbi->longfile) + goto out1; + + /* prefetch root inode */ + root = qnx6_iget(s, QNX6_ROOT_INO); + if (IS_ERR(root)) { + pr_err("get inode failed\n"); + ret = PTR_ERR(root); + goto out2; + } + + ret = -ENOMEM; + s->s_root = d_make_root(root); + if (!s->s_root) + goto out2; + + ret = -EINVAL; + errmsg = qnx6_checkroot(s); + if (errmsg != NULL) { + if (!silent) + pr_err("%s\n", errmsg); + goto out3; + } + return 0; + +out3: + dput(s->s_root); + s->s_root = NULL; +out2: + iput(sbi->longfile); +out1: + iput(sbi->inodes); +out: + if (bh1) + brelse(bh1); + if (bh2) + brelse(bh2); +outnobh: + kfree(qs); + s->s_fs_info = NULL; + return ret; +} + +static void qnx6_put_super(struct super_block *sb) +{ + struct qnx6_sb_info *qs = QNX6_SB(sb); + brelse(qs->sb_buf); + iput(qs->longfile); + iput(qs->inodes); + kfree(qs); + sb->s_fs_info = NULL; + return; +} + +static sector_t qnx6_bmap(struct address_space *mapping, sector_t block) +{ + return generic_block_bmap(mapping, block, qnx6_get_block); +} +static const struct address_space_operations qnx6_aops = { + .readpage = qnx6_readpage, + .readpages = qnx6_readpages, + .bmap = qnx6_bmap +}; + +static struct inode *qnx6_private_inode(struct super_block *s, + struct qnx6_root_node *p) +{ + struct inode *inode = new_inode(s); + if (inode) { + struct qnx6_inode_info *ei = QNX6_I(inode); + struct qnx6_sb_info *sbi = QNX6_SB(s); + inode->i_size = fs64_to_cpu(sbi, p->size); + memcpy(ei->di_block_ptr, p->ptr, sizeof(p->ptr)); + ei->di_filelevels = p->levels; + inode->i_mode = S_IFREG | S_IRUSR; /* probably wrong */ + inode->i_mapping->a_ops = &qnx6_aops; + } + return inode; +} + +struct inode *qnx6_iget(struct super_block *sb, unsigned ino) +{ + struct qnx6_sb_info *sbi = QNX6_SB(sb); + struct qnx6_inode_entry *raw_inode; + struct inode *inode; + struct qnx6_inode_info *ei; + struct address_space *mapping; + struct page *page; + u32 n, offs; + + inode = iget_locked(sb, ino); + if (!inode) + return ERR_PTR(-ENOMEM); + if (!(inode->i_state & I_NEW)) + return inode; + + ei = QNX6_I(inode); + + inode->i_mode = 0; + + if (ino == 0) { + pr_err("bad inode number on dev %s: %u is out of range\n", + sb->s_id, ino); + iget_failed(inode); + return ERR_PTR(-EIO); + } + n = (ino - 1) >> (PAGE_CACHE_SHIFT - QNX6_INODE_SIZE_BITS); + offs = (ino - 1) & (~PAGE_CACHE_MASK >> QNX6_INODE_SIZE_BITS); + mapping = sbi->inodes->i_mapping; + page = read_mapping_page(mapping, n, NULL); + if (IS_ERR(page)) { + pr_err("major problem: unable to read inode from dev %s\n", + sb->s_id); + iget_failed(inode); + return ERR_CAST(page); + } + kmap(page); + raw_inode = ((struct qnx6_inode_entry *)page_address(page)) + offs; + + inode->i_mode = fs16_to_cpu(sbi, raw_inode->di_mode); + i_uid_write(inode, (uid_t)fs32_to_cpu(sbi, raw_inode->di_uid)); + i_gid_write(inode, (gid_t)fs32_to_cpu(sbi, raw_inode->di_gid)); + inode->i_size = fs64_to_cpu(sbi, raw_inode->di_size); + inode->i_mtime.tv_sec = fs32_to_cpu(sbi, raw_inode->di_mtime); + inode->i_mtime.tv_nsec = 0; + inode->i_atime.tv_sec = fs32_to_cpu(sbi, raw_inode->di_atime); + inode->i_atime.tv_nsec = 0; + inode->i_ctime.tv_sec = fs32_to_cpu(sbi, raw_inode->di_ctime); + inode->i_ctime.tv_nsec = 0; + + /* calc blocks based on 512 byte blocksize */ + inode->i_blocks = (inode->i_size + 511) >> 9; + + memcpy(&ei->di_block_ptr, &raw_inode->di_block_ptr, + sizeof(raw_inode->di_block_ptr)); + ei->di_filelevels = raw_inode->di_filelevels; + + if (S_ISREG(inode->i_mode)) { + inode->i_fop = &generic_ro_fops; + inode->i_mapping->a_ops = &qnx6_aops; + } else if (S_ISDIR(inode->i_mode)) { + inode->i_op = &qnx6_dir_inode_operations; + inode->i_fop = &qnx6_dir_operations; + inode->i_mapping->a_ops = &qnx6_aops; + } else if (S_ISLNK(inode->i_mode)) { + inode->i_op = &page_symlink_inode_operations; + inode->i_mapping->a_ops = &qnx6_aops; + } else + init_special_inode(inode, inode->i_mode, 0); + qnx6_put_page(page); + unlock_new_inode(inode); + return inode; +} + +static struct kmem_cache *qnx6_inode_cachep; + +static struct inode *qnx6_alloc_inode(struct super_block *sb) +{ + struct qnx6_inode_info *ei; + ei = kmem_cache_alloc(qnx6_inode_cachep, GFP_KERNEL); + if (!ei) + return NULL; + return &ei->vfs_inode; +} + +static void qnx6_i_callback(struct rcu_head *head) +{ + struct inode *inode = container_of(head, struct inode, i_rcu); + kmem_cache_free(qnx6_inode_cachep, QNX6_I(inode)); +} + +static void qnx6_destroy_inode(struct inode *inode) +{ + call_rcu(&inode->i_rcu, qnx6_i_callback); +} + +static void init_once(void *foo) +{ + struct qnx6_inode_info *ei = (struct qnx6_inode_info *) foo; + + inode_init_once(&ei->vfs_inode); +} + +static int init_inodecache(void) +{ + qnx6_inode_cachep = kmem_cache_create("qnx6_inode_cache", + sizeof(struct qnx6_inode_info), + 0, (SLAB_RECLAIM_ACCOUNT| + SLAB_MEM_SPREAD), + init_once); + if (!qnx6_inode_cachep) + return -ENOMEM; + return 0; +} + +static void destroy_inodecache(void) +{ + /* + * Make sure all delayed rcu free inodes are flushed before we + * destroy cache. + */ + rcu_barrier(); + kmem_cache_destroy(qnx6_inode_cachep); +} + +static struct dentry *qnx6_mount(struct file_system_type *fs_type, + int flags, const char *dev_name, void *data) +{ + return mount_bdev(fs_type, flags, dev_name, data, qnx6_fill_super); +} + +static struct file_system_type qnx6_fs_type = { + .owner = THIS_MODULE, + .name = "qnx6", + .mount = qnx6_mount, + .kill_sb = kill_block_super, + .fs_flags = FS_REQUIRES_DEV, +}; +MODULE_ALIAS_FS("qnx6"); + +static int __init init_qnx6_fs(void) +{ + int err; + + err = init_inodecache(); + if (err) + return err; + + err = register_filesystem(&qnx6_fs_type); + if (err) { + destroy_inodecache(); + return err; + } + + pr_info("QNX6 filesystem 1.0.0 registered.\n"); + return 0; +} + +static void __exit exit_qnx6_fs(void) +{ + unregister_filesystem(&qnx6_fs_type); + destroy_inodecache(); +} + +module_init(init_qnx6_fs) +module_exit(exit_qnx6_fs) +MODULE_LICENSE("GPL"); |